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Sample records for rapid prototyping models

  1. Utilizing Rapid Prototyping for Architectural Modeling

    ERIC Educational Resources Information Center

    Kirton, E. F.; Lavoie, S. D.

    2006-01-01

    This paper will discuss our approach to, success with and future direction in rapid prototyping for architectural modeling. The premise that this emerging technology has broad and exciting applications in the building design and construction industry will be supported by visual and physical evidence. This evidence will be presented in the form of…

  2. Utilizing Rapid Prototyping for Architectural Modeling

    ERIC Educational Resources Information Center

    Kirton, E. F.; Lavoie, S. D.

    2006-01-01

    This paper will discuss our approach to, success with and future direction in rapid prototyping for architectural modeling. The premise that this emerging technology has broad and exciting applications in the building design and construction industry will be supported by visual and physical evidence. This evidence will be presented in the form of…

  3. [A new method of fabricating photoelastic model by rapid prototyping].

    PubMed

    Fan, Li; Huang, Qing-feng; Zhang, Fu-qiang; Xia, Yin-pei

    2011-10-01

    To explore a novel method of fabricating the photoelastic model using rapid prototyping technique. A mandible model was made by rapid prototyping with computerized three-dimensional reconstruction, then the photoelastic model with teeth was fabricated by traditional impression duplicating and mould casting. The photoelastic model of mandible with teeth, which was fabricated indirectly by rapid prototyping, was very similar to the prototype in geometry and physical parameters. The model was of high optical sensibility and met the experimental requirements. Photoelastic model of mandible with teeth indirectly fabricated by rapid prototyping meets the photoelastic experimental requirements well.

  4. Rapid prototype modeling in a multimodality world

    NASA Astrophysics Data System (ADS)

    Bidaut, Luc; Madewell, John; Yasko, Alan

    2006-03-01

    Introduction: Rapid prototype modeling (RPM) has been used in medicine principally for bones - that are easily extracted from CT data sets - for planning orthopaedic, plastic or maxillo-facial interventions, and/or for designing custom prostheses and implants. Based on newly available technology, highly valuable multimodality approaches can now be applied to RPM, particularly for complex musculo-skeletal (MSK) tumors where multimodality often transcends CT alone. Methods: CT data sets are acquired for primary evaluation of MSK tumors in parallel with other modalities (e.g., MR, PET, SPECT). In our approach, CT is first segmented to provide bony anatomy for RPM and all other data sets are then registered to the CT reference. Parametric information relevant to the tumor's characterization is then extracted from the multimodality space and merged with the CT anatomy to produce a hybrid RPM-ready model. This model - that also accommodates digital multimodality visualization - is then produced on the latest generation of 3D printers, which permits both shapes and colors. Results: Multimodality models of complex MSK tumors have been physically produced on modern RPM equipment. This new approach has been found to be a clear improvement over the previously disconnected physical RPM and digital multimodality visualization. Conclusions: New technical developments keep opening doors to sophisticated medical applications that can directly impact the quality of patient care. Although this early work still deals with bones as base models for RPM, its use to encompass soft tissues is already envisioned for future approaches.

  5. Rapid Prototyping

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Javelin, a Lone Peak Engineering Inc. Company has introduced the SteamRoller(TM) System as a commercial product. The system was designed by Javelin during a Phase II NASA funded small commercial product. The purpose of the invention was to allow automated-feed of flexible ceramic tapes to the Laminated Object Manufacturing rapid prototyping equipment. The ceramic material that Javelin was working with during the Phase II project is silicon nitride. This engineered ceramic material is of interest for space-based component.

  6. Rapid prototyping and AI programming environments applied to payload modeling

    NASA Technical Reports Server (NTRS)

    Carnahan, Richard S., Jr.; Mendler, Andrew P.

    1987-01-01

    This effort focused on using artificial intelligence (AI) programming environments and rapid prototyping to aid in both space flight manned and unmanned payload simulation and training. Significant problems addressed are the large amount of development time required to design and implement just one of these payload simulations and the relative inflexibility of the resulting model to accepting future modification. Results of this effort have suggested that both rapid prototyping and AI programming environments can significantly reduce development time and cost when applied to the domain of payload modeling for crew training. The techniques employed are applicable to a variety of domains where models or simulations are required.

  7. Femur Model Reconstruction Based on Reverse Engineering and Rapid Prototyping

    NASA Astrophysics Data System (ADS)

    Tang, Tongming; Zhang, Zheng; Ni, Hongjun; Deng, Jiawen; Huang, Mingyu

    Precise reconstruction of 3D models is fundamental and crucial to the researches of human femur. In this paper we present our approach towards tackling this problem. The surface of a human femur was scanned using a hand-held 3D laser scanner. The data obtained, in the form of point cloud, was then processed using the reverse engineering software Geomagic and the CAD/CAM software CimatronE to reconstruct a digital 3D model. The digital model was then used by the rapid prototyping machine to build a physical model of human femur using 3D printing. The geometric characteristics of the obtained physical model matched that of the original femur. The process of "physical object - 3D data - digital 3D model - physical model" presented in this paper provides a foundation of precise modeling for the digital manufacturing, virtual assembly, stress analysis, and simulated surgery of artificial bionic femurs.

  8. Rapid Prototyping Instructional Design: Revisiting the ISD Model

    ERIC Educational Resources Information Center

    Daugherty, Jenny; Teng, Ya-Ting; Cornachione, Edgard

    2007-01-01

    An exploratory investigation, utilizing mixed methods, was used to examine the quality and usability of the product and the client's role within a rapid prototyping instructional design approach. Forty engineering and business undergraduates participating in a leadership training session and an instructional design team comprised the sample for…

  9. Procedural Modeling for Rapid-Prototyping of Multiple Building Phases

    NASA Astrophysics Data System (ADS)

    Saldana, M.; Johanson, C.

    2013-02-01

    RomeLab is a multidisciplinary working group at UCLA that uses the city of Rome as a laboratory for the exploration of research approaches and dissemination practices centered on the intersection of space and time in antiquity. In this paper we present a multiplatform workflow for the rapid-prototyping of historical cityscapes through the use of geographic information systems, procedural modeling, and interactive game development. Our workflow begins by aggregating archaeological data in a GIS database. Next, 3D building models are generated from the ArcMap shapefiles in Esri CityEngine using procedural modeling techniques. A GIS-based terrain model is also adjusted in CityEngine to fit the building elevations. Finally, the terrain and city models are combined in Unity, a game engine which we used to produce web-based interactive environments which are linked to the GIS data using keyhole markup language (KML). The goal of our workflow is to demonstrate that knowledge generated within a first-person virtual world experience can inform the evaluation of data derived from textual and archaeological sources, and vice versa.

  10. Vibrational testing of trabecular bone architectures using rapid prototype models.

    PubMed

    Mc Donnell, P; Liebschner, M A K; Tawackoli, Wafa; Mc Hugh, P E

    2009-01-01

    The purpose of this study was to investigate if standard analysis of the vibrational characteristics of trabecular architectures can be used to detect changes in the mechanical properties due to progressive bone loss. A cored trabecular specimen from a human lumbar vertebra was microCT scanned and a three-dimensional, virtual model in stereolithography (STL) format was generated. Uniform bone loss was simulated using a surface erosion algorithm. Rapid prototype (RP) replicas were manufactured from these virtualised models with 0%, 16% and 42% bone loss. Vibrational behaviour of the RP replicas was evaluated by performing a dynamic compression test through a frequency range using an electro-dynamic shaker. The acceleration and dynamic force responses were recorded and fast Fourier transform (FFT) analyses were performed to determine the response spectrum. Standard resonant frequency analysis and damping factor calculations were performed. The RP replicas were subsequently tested in compression beyond failure to determine their strength and modulus. It was found that the reductions in resonant frequency with increasing bone loss corresponded well with reductions in apparent stiffness and strength. This suggests that structural dynamics has the potential to be an alternative diagnostic technique for osteoporosis, although significant challenges must be overcome to determine the effect of the skin/soft tissue interface, the cortex and variabilities associated with in vivo testing.

  11. Rapid Prototyping of Hydrologic Model Interfaces with IPython

    NASA Astrophysics Data System (ADS)

    Farthing, M. W.; Winters, K. D.; Ahmadia, A. J.; Hesser, T.; Howington, S. E.; Johnson, B. D.; Tate, J.; Kees, C. E.

    2014-12-01

    A significant gulf still exists between the state of practice and state of the art in hydrologic modeling. Part of this gulf is due to the lack of adequate pre- and post-processing tools for newly developed computational models. The development of user interfaces has traditionally lagged several years behind the development of a particular computational model or suite of models. As a result, models with mature interfaces often lack key advancements in model formulation, solution methods, and/or software design and technology. Part of the problem has been a focus on developing monolithic tools to provide comprehensive interfaces for the entire suite of model capabilities. Such efforts require expertise in software libraries and frameworks for creating user interfaces (e.g., Tcl/Tk, Qt, and MFC). These tools are complex and require significant investment in project resources (time and/or money) to use. Moreover, providing the required features for the entire range of possible applications and analyses creates a cumbersome interface. For a particular site or application, the modeling requirements may be simplified or at least narrowed, which can greatly reduce the number and complexity of options that need to be accessible to the user. However, monolithic tools usually are not adept at dynamically exposing specific workflows. Our approach is to deliver highly tailored interfaces to users. These interfaces may be site and/or process specific. As a result, we end up with many, customized interfaces rather than a single, general-use tool. For this approach to be successful, it must be efficient to create these tailored interfaces. We need technology for creating quality user interfaces that is accessible and has a low barrier for integration into model development efforts. Here, we present efforts to leverage IPython notebooks as tools for rapid prototyping of site and application-specific user interfaces. We provide specific examples from applications in near

  12. Rapid prototype and test

    SciTech Connect

    Gregory, D.L.; Hansche, B.D.

    1996-06-01

    In order to support advanced manufacturing, Sandia has acquired the capability to produce plastic prototypes using stereolithography. Currently, these prototypes are used mainly to verify part geometry and ``fit and form`` checks. This project investigates methods for rapidly testing these plastic prototypes, and inferring from prototype test data actual metal part performance and behavior. Performances examined include static load/stress response, and structural dynamic (modal) and vibration behavior. The integration of advanced non-contacting measurement techniques including scanning laser velocimetry, laser holography, and thermoelasticity into testing of these prototypes is described. Photoelastic properties of the epoxy prototypes to reveal full field stress/strain fields are also explored.

  13. [The basic research on fabricating an ear model by means of rapid prototyping (FDM)].

    PubMed

    Jiao, Ting; Ye, Ming; Zhang, Fu-qiang; Wang, Cheng-tao

    2002-12-01

    The purpose of the study was to reconstruct a 3-D auricular model. Laser scanning was used to get the data of an auricular model, Fused Deposition Manufacturing (one of rapid prototyping technique) was chosen to fabricate an ear cast. The differences between the two models were compared. The result showed that the reconstructed model was precise. This study suggests that the technique of rapid prototyping is precise, convenient, effective and safe to auricular prosthesis.

  14. Application of rapid prototyping techniques for modelling of anatomical structures in medical training and education.

    PubMed

    Torres, K; Staśkiewicz, G; Śnieżyński, M; Drop, A; Maciejewski, R

    2011-02-01

    Rapid prototyping has become an innovative method of fast and cost-effective production of three-dimensional models for manufacturing. Wide access to advanced medical imaging methods allows application of this technique for medical training purposes. This paper presents the feasibility of rapid prototyping technologies: stereolithography, selective laser sintering, fused deposition modelling, and three-dimensional printing for medical education. Rapid prototyping techniques are a promising method for improvement of anatomical education in medical students but also a valuable source of training tools for medical specialists.

  15. Rapid Prototyping in the Instructional Design Process.

    ERIC Educational Resources Information Center

    Nixon, Elizabeth Krick; Lee, Doris

    2001-01-01

    Discusses instructional design models and examines rapid prototyping, a model that combines computer design strategies, constructivist learning theory, and cognitive psychology. Highlights include limitations of linear models; instructional problems appropriate and those not appropriate for rapid prototyping; and rapid prototyping as a paradigm…

  16. Rapid Prototyping Reconsidered

    ERIC Educational Resources Information Center

    Desrosier, James

    2011-01-01

    Continuing educators need additional strategies for developing new programming that can both reduce the time to market and lower the cost of development. Rapid prototyping, a time-compression technique adapted from the high technology industry, represents one such strategy that merits renewed evaluation. Although in higher education rapid…

  17. Rapid Prototyping in PVS

    NASA Technical Reports Server (NTRS)

    Munoz, Cesar A.; Butler, Ricky (Technical Monitor)

    2003-01-01

    PVSio is a conservative extension to the PVS prelude library that provides basic input/output capabilities to the PVS ground evaluator. It supports rapid prototyping in PVS by enhancing the specification language with built-in constructs for string manipulation, floating point arithmetic, and input/output operations.

  18. Rapid Prototyping Reconsidered

    ERIC Educational Resources Information Center

    Desrosier, James

    2011-01-01

    Continuing educators need additional strategies for developing new programming that can both reduce the time to market and lower the cost of development. Rapid prototyping, a time-compression technique adapted from the high technology industry, represents one such strategy that merits renewed evaluation. Although in higher education rapid…

  19. Aerodynamic Properties Analysis of Rapid Prototyped Models Versus Conventional Machined Models

    NASA Technical Reports Server (NTRS)

    Springer, A.; Cooper, K.

    1998-01-01

    Initial studies of the aerodynamic characteristics of proposed launch vehicles can be made more accurately if lower cost, high fidelity aerodynamic models are available for wind tunnel testing early in the design phase. This paper discusses the results of a study undertaken at NASA's Marshall Space Flight Center to determine if four rapid prototyping methods using a variety of materials are suitable for the design and manufacturing of high speed wind tunnel models in direct testing applications. It also gives an analysis of whether these materials and processes are of sufficient strength and fidelity to withstand the testing environment. In addition to test data, costs and turn-around times for the various models are given. Based on the results of this study, it can be concluded that rapid prototyping models show promise in limited direct application for preliminary aerodynamic development studies at subsonic, transonic, and supersonic speeds.

  20. Advances in rapid prototyping

    NASA Astrophysics Data System (ADS)

    Atwood, C. L.; McCarty, G. D.; Pardo, B. T.; Bryce, E. A.

    Recent advances in stereolithography and selective laser sintering have had a significant impact on the overall quality of parts produced using these rapid prototyping processes. The development and implementation of 3D System's QuickCast(trademark) resin and software for building investment casting patterns have proven to be major steps toward fabricating highly accurate patterns with very good surface finishes. Sandia uses patterns generated from rapid prototyping processes to reduce the cycle time and cost of fabricating prototype parts in support of a Sandia National Laboratories managed program called FASTCAST. As participants in the Beta test program for QuickCast(trademark) resin and software, they experienced a steep learning curve and were able to build accurate parts in a short period of time. It is now possible, using this technology, to produce highly accurate prototype parts as well as acceptable first article and small lot size production parts. They use the selective laser sintering (SLS) process to fabricate prototype wax patterns for investment casting. DTM Corporation recently introduced the use of their polycarbonate material for fabricating investment casting patterns. The polycarbonate material is processed significantly faster, with improved strength, dimensional stability, and without a support structure during the build process. Sandia is currently changing from investment casting wax to polycarbonate for the fabrication of investment casting patterns using the SLS process. This presentation will focus on the successes with these new materials from the standpoints of application, accuracy, surface finish, and post processing. Also presented will be examples of parts manufactured by these processes.

  1. Teaching Tip: Using Rapid Game Prototyping for Exploring Requirements Discovery and Modeling

    ERIC Educational Resources Information Center

    Dalal, Nikunj

    2012-01-01

    We describe the use of rapid game prototyping as a pedagogic technique to experientially explore and learn requirements discovery, modeling, and specification in systems analysis and design courses. Students have a natural interest in gaming that transcends age, gender, and background. Rapid digital game creation is used to build computer games…

  2. Teaching Tip: Using Rapid Game Prototyping for Exploring Requirements Discovery and Modeling

    ERIC Educational Resources Information Center

    Dalal, Nikunj

    2012-01-01

    We describe the use of rapid game prototyping as a pedagogic technique to experientially explore and learn requirements discovery, modeling, and specification in systems analysis and design courses. Students have a natural interest in gaming that transcends age, gender, and background. Rapid digital game creation is used to build computer games…

  3. Advances in rapid prototyping

    SciTech Connect

    Atwood, C.L.; McCarty, G.D.; Pardo, B.T.; Bryce, E.A.

    1993-12-31

    Recent advances in stereolithography and selective laser sintering have had a significant impact on the overall quality of parts produced using these rapid prototyping processes. The development and implementation of 3D System`s QuickCast{trademark} resin and software for building investment casting patterns have proven to be major steps toward fabricating highly accurate patterns with very good surface finishes. Sandia uses patterns generated from rapid prototyping processes to reduce the cycle time and cost of fabricating prototype parts in support of a Sandia National Laboratories managed program called FASTCAST. As participants in the Beta test program for QuickCast{trademark} resin and software, they experienced a steep learning curve and were able to build accurate parts in a short period of time. It is now possible, using this technology, to produce highly accurate prototype parts as well as acceptable firs article and small lots size production parts. They use the Selective Laser Sintering (SLS) process to fabricate prototype wax patterns for investment casting. DTM Corporation recently introduced the use of their polycarbonate material for fabricating investment casting patterns. The polycarbonate material is processed significantly faster, with improved strength, dimensional stability, and without a support structure during the build process. Sandia is currently changing from investment casting wax to polycarbonate for the fabrication of investment casting patterns using the SLS process. This presentation will focus on the successes with these new materials from the standpoints of application, accuracy, surface finish, and post processing. Also presented will be examples of parts manufactured by these processes.

  4. Accuracy and reproducibility of dental replica models reconstructed by different rapid prototyping techniques.

    PubMed

    Hazeveld, Aletta; Huddleston Slater, James J R; Ren, Yijin

    2014-01-01

    Rapid prototyping is a fast-developing technique that might play a significant role in the eventual replacement of plaster dental models. The aim of this study was to investigate the accuracy and reproducibility of physical dental models reconstructed from digital data by several rapid prototyping techniques. Twelve mandibular and maxillary conventional plaster models from randomly chosen subjects were selected and served as the gold standard. The plaster models were scanned to form high-resolution 3-dimensional surface models in .stl files. These files were converted into physical models using 3 rapid prototyping techniques: digital light processing, jetted photopolymer, and 3-dimensional printing. Linear measurements on the plaster models were compared with linear measurements on the rapid prototyping models. One observer measured the height and width of the clinical crowns of all teeth (first molar to first molar) on all models (plaster and replicas) using a digital caliper. All models were measured 5 times with a 2-week interval between measurements. The intraobserver agreement was high (intraclass correlation coefficient >0.94). The mean systematic differences for the measurements of the height of the clinical crowns were -0.02 mm for the jetted photopolymer models, 0.04 mm for the digital light processing models, and 0.25 mm for the 3-dimensional printing models. For the width of the teeth, the mean systematic differences were -0.08 mm for the jetted photopolymer models, -0.05 mm for the digital light processing models, and -0.05 mm for the 3-dimensional printing models. Dental models reconstructed by the tested rapid prototyping techniques are considered clinically acceptable in terms of accuracy and reproducibility and might be appropriate for selected applications in orthodontics. Copyright © 2014 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  5. Anisotropic Tensile Failure Model of Rapid Prototyping Parts - Fused Deposition Modeling (FDM)

    NASA Astrophysics Data System (ADS)

    Ahn, Sung Hoon; Baek, Changil; Lee, Sunyoung; Ahn, In Shup

    Stratasys' Fused Deposition Modeling (FDM) is a typical Rapid Prototyping (RP) process that can fabricate prototypes out of plastic materials, and the parts made from FDM were often used as load-carrying elements. Because FDM deposits materials in about 300 μm thin filament with designated orientation, parts made from FDM show anisotropic material behaviors. This paper proposes an analytic model to predict the tensile strength of FDM parts. Applying the Classical Lamination Theory and Tsai-Wu failure criterion, which were developed for laminated composite materials, a computer code was implemented to predict the failure of the FDM parts. The tensile strengths predicted by the analytic model were compared with those of the experimental data. The data and predicted values agreed reasonably well to prove the validity of the model.

  6. Rapid Prototyping 3D Model in Treatment of Pediatric Hip Dysplasia: A Case Report

    PubMed Central

    Holt, Andrew M.; Starosolski, Zbigniew; Kan, J. Herman

    2017-01-01

    Abstract Background: Rapid prototyping is an emerging technology that integrates common medical imaging with specialized production mechanisms to create detailed anatomic replicas. 3D-printed models of musculoskeletal anatomy have already proven useful in orthopedics and their applications continue to expand. Case Description: We present the case of a 10 year-old female with Down syndrome and left acetabular dysplasia and chronic hip instability who underwent periacetabular osteotomy. A rapid prototyping 3D model was created to better understand the anatomy, counsel the family about the problem and the surgical procedure, as well as guide surgical technique. The intricate detail and size match of the model with the patient’s anatomy offered unparalleled, hands-on experience with the patient’s anatomy pre-operatively and improved surgical precision. Conclusions: Our experience with rapid prototyping confirmed its ability to enhance orthopedic care by improving the surgeon’s ability to understand complex anatomy. Additionally, we report a new application utilizing intraoperative fluoroscopic comparison of the model and patient to ensure surgical precision and minimize the risk of complications. This technique could be used in other challenging cases. The increasing availability of rapid prototyping welcomes further use in all areas of orthopedics. PMID:28852351

  7. Rapid Prototyping 3D Model in Treatment of Pediatric Hip Dysplasia: A Case Report.

    PubMed

    Holt, Andrew M; Starosolski, Zbigniew; Kan, J Herman; Rosenfeld, Scott B

    2017-01-01

    Rapid prototyping is an emerging technology that integrates common medical imaging with specialized production mechanisms to create detailed anatomic replicas. 3D-printed models of musculoskeletal anatomy have already proven useful in orthopedics and their applications continue to expand. We present the case of a 10 year-old female with Down syndrome and left acetabular dysplasia and chronic hip instability who underwent periacetabular osteotomy. A rapid prototyping 3D model was created to better understand the anatomy, counsel the family about the problem and the surgical procedure, as well as guide surgical technique. The intricate detail and size match of the model with the patient's anatomy offered unparalleled, hands-on experience with the patient's anatomy pre-operatively and improved surgical precision. Our experience with rapid prototyping confirmed its ability to enhance orthopedic care by improving the surgeon's ability to understand complex anatomy. Additionally, we report a new application utilizing intraoperative fluoroscopic comparison of the model and patient to ensure surgical precision and minimize the risk of complications. This technique could be used in other challenging cases. The increasing availability of rapid prototyping welcomes further use in all areas of orthopedics.

  8. Knowledge-based visual image processing IDE model for algorithm and system rapid prototyping

    NASA Astrophysics Data System (ADS)

    Zhang, Biyin; Chen, Wei; Wang, Yuanbin

    2009-10-01

    A novel intelligent model for Image Processing (IP) research integrated development environment (IDE) is presented for rapid converting conceptual model of IP algorithm into computational model and program implementation. Considering psychology of IP and computer programming, this model presents a cycle model of IP research process and establishes an improved expert system prototype. Visualization approaches are introduced into visualizing three phases of IP development. An intelligent methodology is applied to reuse algorithms, graphical user interfaces (GUI) and data visualizing tools. Thus, researchers are allowed to fix more attention only on their own interest algorithm models. Experimental results show that the development based the new model enhances rapid algorithm prototype modeling with great efficiency and speed.

  9. Rapid Prototyping Roadmapping

    NASA Technical Reports Server (NTRS)

    Cooper, Kenneth G.

    1998-01-01

    Roadmapping has long been thought of as a process for getting from point A to point B within a single discipline. Roadmapping for Rapid Prototyping has multiple paths of which we will diagram in this meeting. When you consider the dynamic change that the computer has made in both developing as well as manufacturing products, we could only assume that further electronic medium matched with mechanical inventions will continue. This industry roadmap is intended to point and lead us to the promised manufacturing land. We hope to reduce the inherent risk associated with technology development by providing a clear goal of mapping to a manufacturing process. The work of DoE in 1994 was excellent and began a journey that would benefit the decision makers and allow for choices that would be good investment decisions. While this work included government agencies, this map is broader and includes industry and academia input.

  10. A three-dimensional mediastinal model created with rapid prototyping in a patient with ectopic thymoma.

    PubMed

    Akiba, Tadashi; Nakada, Takeo; Inagaki, Takuya

    2015-01-01

    Preoperative three-dimensional (3D) imaging of a mediastinal tumor using two-dimensional (2D) axial computed tomography is sometimes difficult, and an unexpected appearance of the tumor may be encountered during surgery. In order to evaluate the preoperative feasibility of a 3D mediastinal model that used the rapid prototyping technique, we created a model and report its results. The 2D image showed some of the relationship between the tumor and the pericardium, but the 3D mediastinal model that was created using the rapid prototyping technique showed the 3D lesion in the outer side of the extrapericardium. The patient underwent a thoracoscopic resection of the tumor, and the pathological examination showed a rare middle mediastinal ectopic thymoma. We believe that the construction of mediastinal models is useful for thoracoscopic surgery and other complicated surgeries of the chest diseases.

  11. A Three-Dimensional Mediastinal Model Created with Rapid Prototyping in a Patient with Ectopic Thymoma

    PubMed Central

    Nakada, Takeo; Inagaki, Takuya

    2014-01-01

    Preoperative three-dimensional (3D) imaging of a mediastinal tumor using two-dimensional (2D) axial computed tomography is sometimes difficult, and an unexpected appearance of the tumor may be encountered during surgery. In order to evaluate the preoperative feasibility of a 3D mediastinal model that used the rapid prototyping technique, we created a model and report its results. The 2D image showed some of the relationship between the tumor and the pericardium, but the 3D mediastinal model that was created using the rapid prototyping technique showed the 3D lesion in the outer side of the extrapericardium. The patient underwent a thoracoscopic resection of the tumor, and the pathological examination showed a rare middle mediastinal ectopic thymoma. We believe that the construction of mediastinal models is useful for thoracoscopic surgery and other complicated surgeries of the chest diseases. PMID:24633133

  12. Application of 3-D printing (rapid prototyping) for creating physical models of pediatric orthopedic disorders.

    PubMed

    Starosolski, Zbigniew A; Kan, J Herman; Rosenfeld, Scott D; Krishnamurthy, Rajesh; Annapragada, Ananth

    2014-02-01

    Three-dimensional printing called rapid prototyping, a technology that is used to create physical models based on a 3-D computer representation, is now commercially available and can be created from CT or MRI datasets. This technical innovation paper reviews the specific requirements and steps necessary to apply biomedical 3-D printing of pediatric musculoskeletal disorders. We discuss its role for the radiologist, orthopedist and patient.

  13. Aortic aneurysm: construction of a life-size model by rapid prototyping.

    PubMed

    Lermusiaux, P; Leroux, C; Tasse, J C; Castellani, L; Martinez, R

    2001-03-01

    Development of new endovascular techniques for repair of abdominal aortic aneurysm (AAA) requires the use of experimental models. Stereolithography is a rapid prototyping technique used in industry to prototype parts during the design phase. A stereolithography apparatus (STL) employs laser technology to build a digital model layer by layer with photopolymer resin. The purpose of this study was to use this technology to produce a life-size AAA model. Data were acquired by CT scan and stored in DICOM 3 format. Specifically designed software was used for 3-D imaging and conversion of data to a standard STL format. Two replicas were made: one to scale and the other 3 mm larger. The final model was made by pouring silicone rubber or polyurethane into the mold over the life-size model so as to obtain a sturdy, life-size, soft, transparent plastic casting. Arterial models made for living subjects with these rapid prototyping techniques can be used to simulate surgical procedures, calibrate imaging modalities, and design new stent grafts.

  14. Use of rapid prototyping models in the planning of percutaneous pulmonary valved stent implantation.

    PubMed

    Armillotta, A; Bonhoeffer, P; Dubini, G; Ferragina, S; Migliavacca, F; Sala, G; Schievano, S

    2007-05-01

    Percutaneous replacement of the pulmonary valve is a recently developed interventional technique which involves the implantation of a valved stent in the pulmonary trunk. It relies upon careful consideration of patient anatomy for both stent design and detailed procedure planning. Medical imaging data in the form of two-dimensional scans and three-dimensional interactive graphics offer only limited support for these tasks. The paper reports the results of an experimental investigation on the use of arterial models built by rapid prototyping techniques. An analysis of clinical needs has helped to specify proper requirements for such model properties as cost, strength, accuracy, elastic compliance, and optical transparency. Two different process chains, based on the fused deposition modelling technique and on the vacuum casting of thermoset resins in rubber moulds, have been tested for prototype fabrication. The use of anatomical models has allowed the cardiologist's confidence in patient selection, prosthesis fabrication, and final implantation to be significantly improved.

  15. Rapid prototyping modelling in oral and maxillofacial surgery: A two year retrospective study

    PubMed Central

    Stoor, Patricia; Mesimäki, Karri; Kontio, Risto K.

    2015-01-01

    Background The use of rapid prototyping (RP) models in medicine to construct bony models is increasing. Material and Methods The aim of the study was to evaluate retrospectively the indication for the use of RP models in oral and maxillofacial surgery at Helsinki University Central Hospital during 2009-2010. Also, the used computed tomography (CT) examination – multislice CT (MSCT) or cone beam CT (CBCT) - method was evaluated. Results In total 114 RP models were fabricated for 102 patients. The mean age of the patients at the time of the production of the model was 50.4 years. The indications for the modelling included malignant lesions (29%), secondary reconstruction (25%), prosthodontic treatment (22%), orthognathic surgery or asymmetry (13%), benign lesions (8%), and TMJ disorders (4%). MSCT examination was used in 92 and CBCT examination in 22 cases. Most of the models (75%) were conventional hard tissue models. Models with colored tumour or other structure(s) of interest were ordered in 24%. Two out of the 114 models were soft tissue models. Conclusions The main benefit of the models was in treatment planning and in connection with the production of pre-bent plates or custom made implants. The RP models both facilitate and improve treatment planning and intraoperative efficiency. Key words:Rapid prototyping, radiology, computed tomography, cone beam computed tomography. PMID:26644837

  16. Rapid prototyping modelling in oral and maxillofacial surgery: A two year retrospective study.

    PubMed

    Suomalainen, Anni; Stoor, Patricia; Mesimäki, Karri; Kontio, Risto K

    2015-12-01

    The use of rapid prototyping (RP) models in medicine to construct bony models is increasing. The aim of the study was to evaluate retrospectively the indication for the use of RP models in oral and maxillofacial surgery at Helsinki University Central Hospital during 2009-2010. Also, the used computed tomography (CT) examination - multislice CT (MSCT) or cone beam CT (CBCT) - method was evaluated. In total 114 RP models were fabricated for 102 patients. The mean age of the patients at the time of the production of the model was 50.4 years. The indications for the modelling included malignant lesions (29%), secondary reconstruction (25%), prosthodontic treatment (22%), orthognathic surgery or asymmetry (13%), benign lesions (8%), and TMJ disorders (4%). MSCT examination was used in 92 and CBCT examination in 22 cases. Most of the models (75%) were conventional hard tissue models. Models with colored tumour or other structure(s) of interest were ordered in 24%. Two out of the 114 models were soft tissue models. The main benefit of the models was in treatment planning and in connection with the production of pre-bent plates or custom made implants. The RP models both facilitate and improve treatment planning and intraoperative efficiency. Rapid prototyping, radiology, computed tomography, cone beam computed tomography.

  17. Customer-experienced rapid prototyping

    NASA Astrophysics Data System (ADS)

    Zhang, Lijuan; Zhang, Fu; Li, Anbo

    2008-12-01

    In order to describe accurately and comprehend quickly the perfect GIS requirements, this article will integrate the ideas of QFD (Quality Function Deployment) and UML (Unified Modeling Language), and analyze the deficiency of prototype development model, and will propose the idea of the Customer-Experienced Rapid Prototyping (CE-RP) and describe in detail the process and framework of the CE-RP, from the angle of the characteristics of Modern-GIS. The CE-RP is mainly composed of Customer Tool-Sets (CTS), Developer Tool-Sets (DTS) and Barrier-Free Semantic Interpreter (BF-SI) and performed by two roles of customer and developer. The main purpose of the CE-RP is to produce the unified and authorized requirements data models between customer and software developer.

  18. Creation of an in vitro biomechanical model of the trachea using rapid prototyping.

    PubMed

    Walenga, Ross L; Longest, P Worth; Sundaresan, Gobalakrishnan

    2014-06-03

    Previous in vitro models of the airways are either rigid or, if flexible, have not matched in vivo compliance characteristics. Rapid prototyping provides a quickly evolving approach that can be used to directly produce in vitro airway models using either rigid or flexible polymers. The objective of this study was to use rapid prototyping to directly produce a flexible hollow model that matches the biomechanical compliance of the trachea. The airway model consisted of a previously developed characteristic mouth-throat region, the trachea, and a portion of the main bronchi. Compliance of the tracheal region was known from a previous in vivo imaging study that reported cross-sectional areas over a range of internal pressures. The compliance of the tracheal region was matched to the in vivo data for a specific flexible resin by iteratively selecting the thicknesses and other dimensions of tracheal wall components. Seven iterative models were produced and illustrated highly non-linear expansion consisting of initial rapid size increase, a transition region, and continued slower size increase as pressure was increased. Thickness of the esophageal interface membrane and initial trachea indention were identified as key parameters with the final model correctly predicting all phases of expansion within a value of 5% of the in vivo data. Applications of the current biomechanical model are related to endotracheal intubation and include determination of effective mucus suctioning and evaluation of cuff sealing with respect to gases and secretions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. [Rapid prototyping: a very promising method].

    PubMed

    Haverman, T M; Karagozoglu, K H; Prins, H-J; Schulten, E A J M; Forouzanfar, T

    2013-03-01

    Rapid prototyping is a method which makes it possible to produce a three-dimensional model based on two-dimensional imaging. Various rapid prototyping methods are available for modelling, such as stereolithography, selective laser sintering, direct laser metal sintering, two-photon polymerization, laminated object manufacturing, three-dimensional printing, three-dimensional plotting, polyjet inkjet technology,fused deposition modelling, vacuum casting and milling. The various methods currently being used in the biomedical sector differ in production, materials and properties of the three-dimensional model which is produced. Rapid prototyping is mainly usedforpreoperative planning, simulation, education, and research into and development of bioengineering possibilities.

  20. The use of a block diagram simulation language for rapid model prototyping

    NASA Technical Reports Server (NTRS)

    Whitlow, Jonathan E.

    1995-01-01

    The research performed this summer focussed on the development of a predictive model for the loading of liquid oxygen (LO2) into the external tank (ET) of the shuttle prior to launch. A predictive model can greatly aid the operational personnel since instrumentation aboard the orbiter and ET is limited due to weight constraints. The model, which focuses primarily on the orbiter section of the system was developed using a block diagram based simulation language known as VisSim. Simulations were run on LO2 loading data for shuttle flights STS50 and STS55 and the model was demonstrated to accurately predict the sensor data recorded for these flights. As a consequence of the simulation results, it can be concluded that the software tool can be very useful for rapid prototyping of complex models.

  1. Physical human lumen carotid reconstruction: life-size models by rapid prototyping

    NASA Astrophysics Data System (ADS)

    Pili, Piero; Murgia, Fabrizio; Pusceddu, Gabriella; Franzoni, Gregorio; Tuveri, Massimiliano

    2003-05-01

    Rapid Prototyping (RP) is a technique used in industry for manufacturing prototypes. Its capability to physically reproduce geometrical complex shapes is getting increasing interest in many fields of medicine. In the field of vascular surgery, replicas of artery lumen have utility in complex cases or when standard imaging is felt to be equivocal. Replicas can also facilitate experimental studies of computational vascular fluid-dynamics permitting in-vitro reproductions of blood flow in living subjects before and after surgery. The VIrtual VAscular (VIVA) project at CRS4, developed a system able to process three-dimensional (3D) datasets extracted from a Computer Tomography (CT) apparatus, visualize them, reconstruct the geometry of arteries of specific patients, and simulate blood flow in them. In this paper, the applicability of RP techniques to VIVA's real size replicas of an autoptic carotid vessel lumen is presented and an overview of the RP based system developed is provided. The techniques used in our prototype are discussed and experimental results for the creation of a human carotid lumen replica are analyzed. We discuss in detail the pipeline of manufacturing process: 3D geometric reconstruction from segmented points, geometry tessellation, STL (Stereo Lithography format) conversion. Moreover we illustrate some technical details of the specific RP technique used to build the lumen replicas, which is called Fused Deposition Modelling (FDM), the materials used for prototypes, throughput time and costs of the FDM models realized. The system is totally based on open-source software. This enables us to control each step of the pipeline, from data acquisition to STL export file. In this context, we present main sources of error encountered during all manufacturing process stages.

  2. Rapid Prototyping of an Aircraft Model in an Object-Oriented Simulation

    NASA Technical Reports Server (NTRS)

    Kenney, P. Sean

    2003-01-01

    A team was created to participate in the Mars Scout Opportunity. Trade studies determined that an aircraft provided the best opportunity to complete the science objectives of the team. A high fidelity six degree of freedom flight simulation was required to provide credible evidence that the aircraft design fulfilled mission objectives and to support the aircraft design process by providing performance evaluations. The team created the simulation using the Langley Standard Real-Time Simulation in C++ (LaSRS++) application framework. A rapid prototyping approach was necessary because the team had only three months to both develop the aircraft simulation model and evaluate aircraft performance as the design and mission parameters matured. The design of LaSRS++ enabled rapid-prototyping in several ways. First, the framework allowed component models to be designed, implemented, unit-tested, and integrated quickly. Next, the framework provides a highly reusable infrastructure that allowed developers to maximize code reuse while concentrating on aircraft and mission specific features. Finally, the framework reduces risk by providing reusable components that allow developers to build a quality product with a compressed testing cycle that relies heavily on unit testing of new components.

  3. The utilization of cranial models created using rapid prototyping techniques in the development of models for navigation training.

    PubMed

    Waran, V; Pancharatnam, Devaraj; Thambinayagam, Hari Chandran; Raman, Rajagopal; Rathinam, Alwin Kumar; Balakrishnan, Yuwaraj Kumar; Tung, Tan Su; Rahman, Z A

    2014-01-01

    Navigation in neurosurgery has expanded rapidly; however, suitable models to train end users to use the myriad software and hardware that come with these systems are lacking. Utilizing three-dimensional (3D) industrial rapid prototyping processes, we have been able to create models using actual computed tomography (CT) data from patients with pathology and use these models to simulate a variety of commonly performed neurosurgical procedures with navigation systems. To assess the possibility of utilizing models created from CT scan dataset obtained from patients with cranial pathology to simulate common neurosurgical procedures using navigation systems. Three patients with pathology were selected (hydrocephalus, right frontal cortical lesion, and midline clival meningioma). CT scan data following an image-guidance surgery protocol in DIACOM format and a Rapid Prototyping Machine were taken to create the necessary printed model with the corresponding pathology embedded. The ability in registration, planning, and navigation of two navigation systems using a variety of software and hardware provided by these platforms was assessed. We were able to register all models accurately using both navigation systems and perform the necessary simulations as planned. Models with pathology utilizing 3D rapid prototyping techniques accurately reflect data of actual patients and can be used in the simulation of neurosurgical operations using navigation systems. Georg Thieme Verlag KG Stuttgart · New York.

  4. Preliminary Component Integration Using Rapid Prototyping Techniques

    NASA Technical Reports Server (NTRS)

    Cooper, Ken; Salvail, Pat; Gordon, Gail (Technical Monitor)

    2001-01-01

    Rapid prototyping is a very important tool that should be used by both design and manufacturing disciplines during the development of elements for the aerospace industry. It helps prevent lack of adequate communication between design and manufacturing engineers (which could lead to costly errors) through mutual consideration of functional models generated from drawings. Rapid prototyping techniques are used to test hardware for design and material compatibility at Marshall Space Flight Center.

  5. D Modelling and Rapid Prototyping for Cardiovascular Surgical Planning - Two Case Studies

    NASA Astrophysics Data System (ADS)

    Nocerino, E.; Remondino, F.; Uccheddu, F.; Gallo, M.; Gerosa, G.

    2016-06-01

    In the last years, cardiovascular diagnosis, surgical planning and intervention have taken advantages from 3D modelling and rapid prototyping techniques. The starting data for the whole process is represented by medical imagery, in particular, but not exclusively, computed tomography (CT) or multi-slice CT (MCT) and magnetic resonance imaging (MRI). On the medical imagery, regions of interest, i.e. heart chambers, valves, aorta, coronary vessels, etc., are segmented and converted into 3D models, which can be finally converted in physical replicas through 3D printing procedure. In this work, an overview on modern approaches for automatic and semiautomatic segmentation of medical imagery for 3D surface model generation is provided. The issue of accuracy check of surface models is also addressed, together with the critical aspects of converting digital models into physical replicas through 3D printing techniques. A patient-specific 3D modelling and printing procedure (Figure 1), for surgical planning in case of complex heart diseases was developed. The procedure was applied to two case studies, for which MCT scans of the chest are available. In the article, a detailed description on the implemented patient-specific modelling procedure is provided, along with a general discussion on the potentiality and future developments of personalized 3D modelling and printing for surgical planning and surgeons practice.

  6. Rapid Prototyping Enters Mainstream Manufacturing.

    ERIC Educational Resources Information Center

    Winek, Gary

    1996-01-01

    Explains rapid prototyping, a process that uses computer-assisted design files to create a three-dimensional object automatically, speeding the industrial design process. Five commercially available systems and two emerging types--the 3-D printing process and repetitive masking and depositing--are described. (SK)

  7. Rapid Prototyping Enters Mainstream Manufacturing.

    ERIC Educational Resources Information Center

    Winek, Gary

    1996-01-01

    Explains rapid prototyping, a process that uses computer-assisted design files to create a three-dimensional object automatically, speeding the industrial design process. Five commercially available systems and two emerging types--the 3-D printing process and repetitive masking and depositing--are described. (SK)

  8. Mandibular reconstruction using plates prebent to fit rapid prototyping 3-dimensional printing models ameliorates contour deformity.

    PubMed

    Azuma, Masaki; Yanagawa, Toru; Ishibashi-Kanno, Naomi; Uchida, Fumihiko; Ito, Takaaki; Yamagata, Kenji; Hasegawa, Shogo; Sasaki, Kaoru; Adachi, Koji; Tabuchi, Katsuhiko; Sekido, Mitsuru; Bukawa, Hiroki

    2014-10-23

    Recently, medical rapid prototyping (MRP) models, fabricated with computer-aided design and computer-aided manufacture (CAD/CAM) techniques, have been applied to reconstructive surgery in the treatment of head and neck cancers. Here, we tested the use of preoperatively manufactured reconstruction plates, which were produced using MRP models. The clinical efficacy and esthetic outcome of using these products in mandibular reconstruction was evaluated. A series of 28 patients with malignant oral tumors underwent unilateral segmental resection of the mandible and simultaneous mandibular reconstruction. Twelve patients were treated with prebent reconstruction plates that were molded to MRP mandibular models designed with CAD/CAM techniques and fabricated on a combined powder bed and inkjet head three-dimensional printer. The remaining 16 patients were treated using conventional reconstruction methods. The surgical and esthetic outcomes of the two groups were compared by imaging analysis using post-operative panoramic tomography. The mandibular symmetry in patients receiving the MRP-model-based prebent plates was significantly better than that in patients receiving conventional reconstructive surgery. Patients with head and neck cancer undergoing reconstructive surgery using a prebent reconstruction plate fabricated according to an MRP mandibular model showed improved mandibular contour compared to patients undergoing conventional mandibular reconstruction. Thus, use of this new technology for mandibular reconstruction results in an improved esthetic outcome with the potential for improved quality of life for patients.

  9. Creating pathology models from MRI data: a comparison of virtual 3D modelling and rapid prototyping techniques.

    PubMed

    Challoner, Alexandra; Erolin, Caroline

    2013-06-01

    This paper discusses a pilot study in collaboration between the Centre for Anatomy and Human Identification and the Pathology Department at Ninewells Hospital, Dundee. Anonymised patient MRI data depicting renal cancer was used to create a virtual 3D model and two rapid prototype models of the kidneys and surrounding anatomy. A questionnaire was conducted to collect feedback from tutors and students in order to evaluate the models and determine user preference. It was found that the majority preferred the physical models to the virtual model.

  10. Rapid Prototyping: State of the Art

    DTIC Science & Technology

    2003-10-23

    Inkjet and 3D Printing • Lamination Stereolithography was the first type of rapid prototyping technology to be introduced commercially and it...includes processes such as stereolithography, fused deposition modeling, laser sintering, and 3D inkjet printing. RP systems produce models, prototype...Process. 5 A final example, inkjet printing, is shown in Figure 5. Unlike the previous examples, the laser is replaced with an inkjet head that deposits a

  11. Rapid mask prototyping for microfluidics.

    PubMed

    Maisonneuve, B G C; Honegger, T; Cordeiro, J; Lecarme, O; Thiry, T; Fuard, D; Berton, K; Picard, E; Zelsmann, M; Peyrade, D

    2016-03-01

    With the rise of microfluidics for the past decade, there has come an ever more pressing need for a low-cost and rapid prototyping technology, especially for research and education purposes. In this article, we report a rapid prototyping process of chromed masks for various microfluidic applications. The process takes place out of a clean room, uses a commercially available video-projector, and can be completed in less than half an hour. We quantify the ranges of fields of view and of resolutions accessible through this video-projection system and report the fabrication of critical microfluidic components (junctions, straight channels, and curved channels). To exemplify the process, three common devices are produced using this method: a droplet generation device, a gradient generation device, and a neuro-engineering oriented device. The neuro-engineering oriented device is a compartmentalized microfluidic chip, and therefore, required the production and the precise alignment of two different masks.

  12. Comparison of reconstructed rapid prototyping models produced by 3-dimensional printing and conventional stone models with different degrees of crowding.

    PubMed

    Wan Hassan, Wan Nurazreena; Yusoff, Yusnilawati; Mardi, Noor Azizi

    2017-01-01

    Rapid prototyping models can be reconstructed from stereolithographic digital study model data to produce hard-copy casts. In this study, we aimed to compare agreement and accuracy of measurements made with rapid prototyping and stone models for different degrees of crowding. The Z Printer 450 (3D Systems, Rock Hill, SC) reprinted 10 sets of models for each category of crowding (mild, moderate, and severe) scanned using a structured-light scanner (Maestro 3D, AGE Solutions, Pisa, Italy). Stone and RP models were measured using digital calipers for tooth sizes in the mesiodistal, buccolingual, and crown height planes and for arch dimension measurements. Bland-Altman and paired t test analyses were used to assess agreement and accuracy. Clinical significance was set at ±0.50 mm. Bland-Altman analysis showed the mean bias of measurements between the models to be within ±0.15 mm (SD, ±0.40 mm), but the 95% limits of agreement exceeded the cutoff point of ±0.50 mm (lower range, -0.81 to -0.41 mm; upper range, 0.34 to 0.76 mm). Paired t tests showed statistically significant differences for all planes in all categories of crowding except for crown height in the moderate crowding group and arch dimensions in the mild and moderate crowding groups. The rapid prototyping models were not clinically comparable with conventional stone models regardless of the degree of crowding. Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  13. Rapid prototyping and stereolithography in dentistry.

    PubMed

    Nayar, Sanjna; Bhuminathan, S; Bhat, Wasim Manzoor

    2015-04-01

    The word rapid prototyping (RP) was first used in mechanical engineering field in the early 1980s to describe the act of producing a prototype, a unique product, the first product, or a reference model. In the past, prototypes were handmade by sculpting or casting, and their fabrication demanded a long time. Any and every prototype should undergo evaluation, correction of defects, and approval before the beginning of its mass or large scale production. Prototypes may also be used for specific or restricted purposes, in which case they are usually called a preseries model. With the development of information technology, three-dimensional models can be devised and built based on virtual prototypes. Computers can now be used to create accurately detailed projects that can be assessed from different perspectives in a process known as computer aided design (CAD). To materialize virtual objects using CAD, a computer aided manufacture (CAM) process has been developed. To transform a virtual file into a real object, CAM operates using a machine connected to a computer, similar to a printer or peripheral device. In 1987, Brix and Lambrecht used, for the first time, a prototype in health care. It was a three-dimensional model manufactured using a computer numerical control device, a type of machine that was the predecessor of RP. In 1991, human anatomy models produced with a technology called stereolithography were first used in a maxillofacial surgery clinic in Viena.

  14. Rapid prototyping and stereolithography in dentistry

    PubMed Central

    Nayar, Sanjna; Bhuminathan, S.; Bhat, Wasim Manzoor

    2015-01-01

    The word rapid prototyping (RP) was first used in mechanical engineering field in the early 1980s to describe the act of producing a prototype, a unique product, the first product, or a reference model. In the past, prototypes were handmade by sculpting or casting, and their fabrication demanded a long time. Any and every prototype should undergo evaluation, correction of defects, and approval before the beginning of its mass or large scale production. Prototypes may also be used for specific or restricted purposes, in which case they are usually called a preseries model. With the development of information technology, three-dimensional models can be devised and built based on virtual prototypes. Computers can now be used to create accurately detailed projects that can be assessed from different perspectives in a process known as computer aided design (CAD). To materialize virtual objects using CAD, a computer aided manufacture (CAM) process has been developed. To transform a virtual file into a real object, CAM operates using a machine connected to a computer, similar to a printer or peripheral device. In 1987, Brix and Lambrecht used, for the first time, a prototype in health care. It was a three-dimensional model manufactured using a computer numerical control device, a type of machine that was the predecessor of RP. In 1991, human anatomy models produced with a technology called stereolithography were first used in a maxillofacial surgery clinic in Viena. PMID:26015715

  15. A validation study of reconstructed rapid prototyping models produced by two technologies.

    PubMed

    Dietrich, Christian Andreas; Ender, Andreas; Baumgartner, Stefan; Mehl, Albert

    2017-09-01

    To determine the accuracy (trueness and precision) of two different rapid prototyping (RP) techniques for the physical reproduction of three-dimensional (3D) digital orthodontic study casts, a comparative assessment using two 3D STL files of two different maxillary dentitions (two cases) as a reference was accomplished. Five RP replicas per case were fabricated using both stereolithography (SLA) and the PolyJet system. The 20 reproduced casts were digitized with a highly accurate reference scanner, and surface superimpositions were performed. Precision was measured by superimposing the digitized replicas within each case with themselves. Superimposing the digitized replicas with the corresponding STL reference files assessed trueness. Statistical significance between the two tested RP procedures was evaluated with independent-sample t-tests (P < .05). The SLA and PolyJet replicas showed statistically significant differences for trueness and precision. The precision of both tested RP systems was high, with mean deviations in stereolithographic models of 23 (±6) μm and in PolyJet replicas of 46 (±13) μm. The mean deviation for trueness in stereolithographic replicas was 109 (±4) μm, while in PolyJet replicas, it was 66 (±14) μm. Comparing the STL reference files, the PolyJet replicas showed higher trueness than the SLA models. But the precision measurements favored the SLA technique. The dimensional errors observed in this study were a maximum of 127 μm. In the present study, both types of reproduced digital orthodontic models are suitable for diagnostics and treatment planning.

  16. Assessment of Mechanical Performance of Bone Architecture Using Rapid Prototyping Models

    NASA Astrophysics Data System (ADS)

    Saparin, Peter; Woesz, Alexander; Thomsen, Jasper S.; Fratzl, Peter

    2008-06-01

    The aim of this on-going research project is to assess the influence of bone microarchitecture on the mechanical performance of trabecular bone. A testing chain consist-ing of three steps was established: 1) micro computed tomography (μCT) imaging of human trabecular bone; 2) building of models of the bone from a light-sensitive polymer using Rapid Prototyping (RP); 3) mechanical testing of the models in a material testing machine. A direct resampling procedure was developed to convert μCT data into the format of the RP machine. Standardized parameters for production and testing of the plastic models were established by use of regular cellular structures. Next, normal, osteoporotic, and extreme osteoporotic vertebral trabecular bone architectures were re-produced by RP and compression tested. We found that normal architecture of vertebral trabecular bone exhibit behaviour characteristic of a cellular structure. In normal bone the fracture occurs at much higher strain values that in osteoporotic bone. After the fracture a normal trabecular architecture is able to carry much higher loads than an osteoporotic architecture. However, no statistically significant differences were found in maximal stress during uniaxial compression of the central part of normal, osteoporotic, and extreme osteoporotic vertebral trabecular bone. This supports the hypothesis that osteoporotic trabecular bone can compensate for a loss of trabeculae by thickening the remaining trabeculae in the loading direction (compensatory hypertrophy). The developed approach could be used for mechanical evaluation of structural data acquired non-invasively and assessment of changes in performance of bone architecture.

  17. Rapid prototyping of pulse oximeter.

    PubMed

    Jalan, P; Bracio, B R; Rider, P J; Toniolo, H

    2006-01-01

    Measurement of oxygen saturation levels in blood is a vital activity during most medical treatments. A pulse oximeter is a device most commonly used to perform this measurement. It provides convenient, non-invasive and continuous monitoring of oxygen levels in a human body. However, it is often a tedious task to select the appropriate hardware and software components to manufacture a pulse oximeter that gives accurate results. This paper describes a student project, which had the goals to expose the student to this important technique of applying rapid prototyping methods to the design of a state of the art pulse oximeter.

  18. Rapid prototyping applications for manufacturing

    SciTech Connect

    Atwood, C.L.; Maguire, M.C.; Pardo, B.T.; Bryce, E.A.

    1996-01-01

    Recent advances in stereolithography and selective laser sintering have had a significant impact on the overall quality of parts produced using these rapid prototyping processes. The development and implementation of 3D System`s QuickCast{sup TM} resin and software for building investment casting patterns have proven to be major steps toward fabricating highly accurate patterns with very good surface finishes. As participants in the Beta test program for QuickCast{sup TM} resin and software, we experienced a steep learning curve and were able to build accurate parts in a short period of time. It is now possible using this technology to produce highly accurate prototype parts as well as acceptable first article and small lot size production parts. We use the Selective Laser Sintering (SLS) process to fabricate prototype wax patterns for investment casting. DTM Corporation recently introduced the use of their polycarbonate material for fabricating investment casting patterns. The polycarbonate material is processed significantly faster with improved strength, dimensional stability, and without a support structure during the build process. Sandia is currently changing from investment casting wax to polycarbonate for the fabrication of investment casting patterns using the SLS process. This report will focus on our successes with these new materials from the standpoints of application, accuracy, surface finish, and post processing. Also presented will be examples of parts manufactured by these processes. 6 refs., 10 figs.

  19. Classroom Evaluation of a Rapid Prototyping System.

    ERIC Educational Resources Information Center

    Tennyson, Stephen A.; Krueger, Thomas J.

    2001-01-01

    Introduces rapid prototyping which creates virtual models through a variety of automated material additive processes. Relates experiences using JP System 5 in freshman and sophomore engineering design graphics courses. Analyzes strengths and limitations of the JP System 5 and discusses how to use it effectively. (Contains 15 references.)…

  20. Parametric Modeling as a Technology of Rapid Prototyping in Light Industry

    NASA Astrophysics Data System (ADS)

    Tomilov, I. N.; Grudinin, S. N.; Frolovsky, V. D.; Alexandrov, A. A.

    2016-04-01

    The paper deals with the parametric modeling method of virtual mannequins for the purposes of design automation in clothing industry. The described approach includes the steps of generation of the basic model on the ground of the initial one (obtained in 3D-scanning process), its parameterization and deformation. The complex surfaces are presented by the wireframe model. The modeling results are evaluated with the set of similarity factors. Deformed models are compared with their virtual prototypes. The results of modeling are estimated by the standard deviation factor.

  1. UGV application modeling and sensor simulation using a rapid prototyping testbed environment

    NASA Astrophysics Data System (ADS)

    Falasco, James; O'Leary, Steve

    2009-05-01

    This paper reviews hardware and software solutions that allow for rapid prototyping of new or modified UGV sensor designs, mission payloads and functional sub assemblies. We define reconfigurable computing in the context of being able to place various PMC modules depending upon mission scenarios onto a base SBC (Single Board Computer) or multiprocessor architectures to achieve maximum scalability. Also addressed are the sensor and computing packaging aspects and how such payloads could be integrated with unattended acoustic sensor topologies providing a more complete fused "picture" to decision makers. We review how these modular payloads could be integrated with unattended ground sensors to collaborate on mission requirements

  2. Rapid prototyping applications at Sandia National Laboratories

    NASA Astrophysics Data System (ADS)

    Atwood, C. L.; McCarty, G. D.; Pardo, B. T.; Bryce, E. A.

    In an effort to reduce the cycle time for producing prototypical mechanical and electro-mechanical components, Sandia National Laboratories has integrated rapid prototyping processes into the design and manufacturing process. The processes currently in operation within the Rapid Prototyping Laboratory are Stereolithography (SL), Selective Laser Sintering (SLS), and Direct Shell Production Casting (DSPC). These emerging technologies have proven to be valuable tools for reducing lead times and fabrication costs. Sandia uses the SL and SLS processes to support internal product development efforts. Their primary use is to fabricate patterns for investment casting in support of a Sandia-managed program called FASTCAST that integrates computational technologies and experimental data into the investment casting process. These processes are also used in the design iteration process to produce proof-of-concept models, hands-on models for design reviews, fit-check models, visual aids for manufacturing, and functional parts in assemblies. The DSPC process is currently being developed as a method of fabricating ceramic investment casting molds directly from a CAD solid model. Sandia is an Alpha machine test site for this process. This presentation will provide an overview of the SL and SLS processes and an update of our experience and success in integrating these technologies into the product development cycle. It will also provide a lead-in for a tour of the Rapid Prototyping Laboratory, where these processes will be demonstrated.

  3. Rapid prototyping applications at Sandia National Laboratories

    SciTech Connect

    Atwood, C.L.; McCarty, G.D.; Pardo, B.T.; Bryce, E.A.

    1994-02-01

    In an effort to reduce the cycle time for producing prototypical mechanical and electro-mechanical components, Sandia National Laboratories has integrated rapid prototyping processes into the design and manufacturing process. The processes currently in operation within the Rapid Prototyping Laboratory are Stereolithography (SL), Selective Laser Sintering (SLS), and Direct Shell Production Casting (DSPC). These emerging technologies have proven to be valuable tools for reducing lead times and fabrication costs. Sandia uses the SL and SLS processes to support internal product development efforts. Their primary use is to fabricate patterns for investment casting in support of a Sandia-managed program called FASTCAST that integrates computational technologies and experimental data into the investment casting process. These processes are also used in the design iteration process to produce proof-of-concept models, hands-on models for design reviews, fit-check models, visual aids for manufacturing, and functional parts in assemblies. The DSPC process is currently being developed as a method of fabricating ceramic investment casting molds directly from a CAD solid model. Sandia is an Alpha machine test site for this process. This presentation will provide an overview of the SL and SLS processes and an update of our experience and success in integrating these technologies into the product development cycle. It will also provide a lead-in for a tour of the Rapid Prototyping Laboratory, where these processes will be demonstrated.

  4. Growth of the chorioallantoic membrane into a rapid-prototyped model pore system: experiments and mathematical model.

    PubMed

    Lemon, Greg; Howard, Daniel; Yang, Hongyi; Ratchev, Svetan M; Segal, Joel I; Rose, Felicity R A J; Jensen, Oliver E; Waters, Sarah L; King, John R

    2011-07-01

    This paper presents a mathematical model to describe the growth of tissue into a rapid-prototyped porous scaffold when it is implanted onto the chorioallantoic membrane (CAM). The scaffold was designed to study the effects of the size and shape of pores on tissue growth into conventional tissue engineering scaffolds, and consists of an array of pores each having a pre-specified shape. The experimental observations revealed that the CAM grows through each pore as an intact layer of tissue, provided the width of the pore exceeds a threshold value. Based on these results a mathematical model is described to simulate the growth of the membrane, assuming that the growth is a function of the local isotropic membrane tension. The model predictions are compared against measurements of the extent of membrane growth through the pores as a function of time for pores with different dimensions.

  5. Aeroelastic characteristics of a rapid prototype multi-material wind tunnel model of a mechanically deployable aerodynamic decelerator

    NASA Astrophysics Data System (ADS)

    Raskin, Boris

    Scaled wind tunnel models are necessary for the development of aircraft and spacecraft to simulate aerodynamic behavior. This allows for testing multiple iterations of a design before more expensive full-scale aircraft and spacecraft are built. However, the cost of building wind tunnel models can still be high because they normally require costly subtractive manufacturing processes, such as machining, which can be time consuming and laborious due to the complex surfaces of aerodynamic models. Rapid prototyping, commonly known as 3D printing, can be utilized to save on wind tunnel model manufacturing costs. A rapid prototype multi-material wind tunnel model was manufactured for this thesis to investigate the possibility of using PolyJet 3D printing to create a model that exhibits aeroelastic behavior. The model is of NASA's Adaptable Deployable entry and Placement (ADEPT) aerodynamic decelerator, used to decelerate a spacecraft during reentry into a planet's atmosphere. It is a 60° cone with a spherically blunted nose that consists of a 12 flexible panels supported by a rigid structure of nose, ribs, and rim. The novel rapid prototype multi-material model was instrumented and tested in two flow conditions. Quantitative comparisons were made of the average forces and dynamic forces on the model, demonstrating that the model matched expected behavior for average drag, but not Strouhal number, indicating that there was no aeroelastic behavior in this particular case. It was also noted that the dynamic properties (e.g., resonant frequency) associated with the mounting scheme are very important and may dominate the measured dynamic response.

  6. Rapid Prototyping in Instructional Design: Creating Competencies

    ERIC Educational Resources Information Center

    Fulton, Carolyn D.

    2010-01-01

    Instructional designers working in rapid prototyping environments currently do not have a list of competencies that help to identify the knowledge, skills, and attitudes (KSAs) required in these workplaces. This qualitative case study used multiple cases in an attempt to identify rapid prototyping competencies required in a rapid prototyping…

  7. Thoracoscopic anatomical subsegmentectomy of the right S2b + S3 using a 3D printing model with rapid prototyping.

    PubMed

    Nakada, Takeo; Akiba, Tadashi; Inagaki, Takuya; Morikawa, Toshiaki

    2014-10-01

    Thoracoscopic segmentectomies and subsegmentectomies are more difficult than lobectomy because of the complexity of the procedure; therefore, preoperative decision-making and surgical procedure planning are essential. In the literature, we could successfully perform thoracoscopic anatomical subsegmentectomy of the right S2b + S3 using a 3D printing model with rapid prototyping. This innovative surgical support model is extremely useful for planning a surgical procedure and identifying the surgical margin. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  8. Integration of rapid prototyping into product development

    SciTech Connect

    Atwood, C.L.; McCarty, G.D.; Pardo, B.T.; Bryce, E.A.

    1993-12-31

    Sandia National Laboratories is a vertically multi-disciplined research and development laboratory with a long history of designing and developing d electro-mechanical products in the national interest. Integrating new technologies into the prototyping phase of our development cycle is necessary to reduce the cycle time from initial design to finished product. The introduction of rapid prototyping machines into the marketplace promises to revolutionize the process of producing prototype parts with relative speed and production-like quality. Issues of accuracy, feature definition, and surface finish continue to drive research and development of these processes. Sandia uses Stereolithography (SL) and Selective Laser Sintering (SLS) capabilities to support internal product development efforts. The primary use of SL and SLS is to produce patterns for investment casting in support of a Sandia managed program called FASTCAST that integrates computational technologies and experimental data into the investment casting process. These processes are also used in the design iteration process to produce proof-of-concept models, hands-on models for design reviews, fit-check models, visual aids for manufacturing, and functional parts in assemblies. This presentation will provide an overview of the SL and SLS processes and an update of our experience and success in integrating these technologies into the product development cycle. Also presented will be several examples of prototype parts manufactured using SL and SLS with a focus on application, accuracy, surface and feature definition.

  9. Rapid Prototyping of Mobile Learning Games

    ERIC Educational Resources Information Center

    Federley, Maija; Sorsa, Timo; Paavilainen, Janne; Boissonnier, Kimo; Seisto, Anu

    2014-01-01

    This position paper presents the first results of an on-going project, in which we explore rapid prototyping method to efficiently produce digital learning solutions that are commercially viable. In this first phase, rapid game prototyping and an iterative approach was tested as a quick and efficient way to create learning games and to evaluate…

  10. Mirror-Imaged Rapid Prototype Skull Model and Pre-Molded Synthetic Scaffold to Achieve Optimal Orbital Cavity Reconstruction.

    PubMed

    Park, Sung Woo; Choi, Jong Woo; Koh, Kyung S; Oh, Tae Suk

    2015-08-01

    Reconstruction of traumatic orbital wall defects has evolved to restore the original complex anatomy with the rapidly growing use of computer-aided design and prototyping. This study evaluated a mirror-imaged rapid prototype skull model and a pre-molded synthetic scaffold for traumatic orbital wall reconstruction. A single-center retrospective review was performed of patients who underwent orbital wall reconstruction after trauma from 2012 to 2014. Patients were included by admission through the emergency department after facial trauma or by a tertiary referral for post-traumatic orbital deformity. Three-dimensional (3D) computed tomogram-based mirror-imaged reconstruction images of the orbit and an individually manufactured rapid prototype skull model by a 3D printing technique were obtained for each case. Synthetic scaffolds were anatomically pre-molded using the skull model as guide and inserted at the individual orbital defect. Postoperative complications were assessed and 3D volumetric measurements of the orbital cavity were performed. Paired samples t test was used for statistical analysis. One hundred four patients with immediate orbital defect reconstructions and 23 post-traumatic orbital deformity reconstructions were included in this study. All reconstructions were successful without immediate postoperative complications, although there were 10 cases with mild enophthalmos and 2 cases with persistent diplopia. Reoperations were performed for 2 cases of persistent diplopia and secondary touchup procedures were performed to contour soft tissue in 4 cases. Postoperative volumetric measurement of the orbital cavity showed nonsignificant volume differences between the damaged orbit and the reconstructed orbit (21.35 ± 1.93 vs 20.93 ± 2.07 cm(2); P = .98). This protocol was extended to severe cases in which more than 40% of the orbital frame was lost and combined with extensive soft tissue defects. Traumatic orbital reconstruction can be optimized and

  11. Morphology of elastase-induced cerebral aneurysm model in rabbit and rapid prototyping of elastomeric transparent replicas.

    PubMed

    Seong, Jaehoon; Sadasivan, Chander; Onizuka, Masanari; Gounis, Matthew J; Christian, Fletcher; Miskolczi, Laszlo; Wakhloo, Ajay K; Lieber, Baruch B

    2005-01-01

    In this work, we describe a methodology to fabricate transparent elastomeric vascular replicas using rapid prototyping techniques. First, the three-dimensional morphology of an elastase-induced aneurysm model in rabbit is acquired. The morphology is reconstructed from in vivo rotational angiography and it is compared with three-dimensional reconstructions obtained by computerized tomography and magnetic resonance imaging of an intraluminal arterial cast that was obtained from the same animal at sacrifice. Results show that resolution of the imaging modality strongly influences the level of detail, such as small side branches, in the final reconstruction. We developed an average morphology model for elastase-induced aneurysms in rabbits including the surrounding vasculature and describe a method for rapid prototyping of vascular models from the three-dimensional morphology. Our replicas can be manufactured in a short period of time and the final product is optically clear. In addition, the elasticity of the models can be controlled to represent arterial elasticity, which makes them ideal for optical investigations of detailed flow dynamics using measurement tools such as particle image velocimetry.

  12. Architecture and design to support rapid prototyping and multiple dynamic models for the Virtual SpacePlane project

    NASA Astrophysics Data System (ADS)

    Banks, Sheila B.; Stytz, Martin R.; Rothermel, Scott A.; Johnson, Troy D.

    1998-08-01

    The advent of requirements for rapid and economical deployment of national space assets in support of Air Force operational missions has resulted in the need for a Manned SpacePlane (MSP) that can perform military missions with minimal preflight preparation and little if any in-orbit support from a mission control center. In this new approach to space operations, successful mission accomplishment will depend almost completely upon the MSP crew and upon the on- board capabilities of the spaceplane. In recognition of the challenges that will be faced by the MSP crew and to begin to address these challenges, the USAF Air Force Research Laboratory (Phillips Laboratory) initiated the Virtual SpacePlane (VSP) project. To support the MSP, the VSP must demonstrate a broad, functional subset of the anticipated missions and capabilities of the MSP throughout its entire flight regime, from takeoff through space operations and on through landing. Additionally, the VSP must execute the anticipated MSP missions in a realistic and tactically sound manner within a distributed virtual environment. Furthermore, the VSP project must also uncover, refine and validate MSP user interface requirements, design and demonstrate an intelligent user interface for the VSP, and design and implement a prototype VSP that can be used to demonstrate Manned SpacePlane missions. To enable us to make rapid progress on the project, we employed portions of the Virtual Cockpit and Solar System Modeler distributed virtual environment applications, and the Common Object Database (CODB) architecture tools developed in our labs. The Virtual Cockpit and Solar System Modeler supplied baseline interface components and tools, 3D graphical models, vehicle motion dynamics models, and VE communication capabilities. We use the CODB architecture to facilitate our use of Rapid Evolutionary and Exploratory Prototyping to uncover application requirements and evaluate solutions. The Information Pod provides the paradigm

  13. Web tools for rapid experimental visualization prototyping

    NASA Astrophysics Data System (ADS)

    Decker, Jonathan W.; Livingstion, Mark A.

    2013-01-01

    Quite often a researcher finds themselves looking at spreadsheets of high-dimensional data generated by experimental models and user studies. We can use analysis to challenge or confirm hypothesis, but unexpected results can easily be lost in the shuffle. For this reason, it would be useful to visualize the results so we can explore our data and make new discoveries. Web browsers have become increasingly capable for creating complex, multi-view applications. Javascript is quickly becoming a de facto standard for scripting, online and offline. This work demonstrates the use of web technologies as a powerful tool for rapid visualization prototyping. We have developed two prototypes: One for high-dimensional results of the abELICIT - multi-agent version of the ELICIT platform tasked with collaborating to identify the parameters of a pending attack. Another prototype displays responses to a user study on the effectiveness of multi-layer visualization techniques. We created coordinated multiple views prototypes in the Google Chrome web browser written in Javascript, CSS and HTML. We will discuss the benefits and shortcomings of this approach.

  14. Review on CNC-Rapid Prototyping

    NASA Astrophysics Data System (ADS)

    Z, M. Nafis O.; Y, Nafrizuan M.; A, Munira M.; J, Kartina

    2012-09-01

    This article reviewed developments of Computerized Numerical Control (CNC) technology in rapid prototyping process. Rapid prototyping (RP) can be classified into three major groups; subtractive, additive and virtual. CNC rapid prototyping is grouped under the subtractive category which involves material removal from the workpiece that is larger than the final part. Richard Wysk established the use of CNC machines for rapid prototyping using sets of 2½-D tool paths from various orientations about a rotary axis to machine parts without refixturing. Since then, there are few developments on this process mainly aimed to optimized the operation and increase the process capabilities to stand equal with common additive type of RP. These developments include the integration between machining and deposition process (hybrid RP), adoption of RP to the conventional machine and optimization of the CNC rapid prototyping process based on controlled parameters. The article ended by concluding that the CNC rapid prototyping research area has a vast space for improvement as in the conventional machining processes. Further developments and findings will enhance the usage of this method and minimize the limitation of current approach in building a prototype.

  15. Preliminary Component Integration Utilizing Rapid Prototyping Techniques

    NASA Technical Reports Server (NTRS)

    Cooper, K.; Salvail, P.

    2001-01-01

    One of the most costly errors committed during the development of an element to be used in the space industry is the lack of communication between design and manufacturing engineers. A very important tool that should be utilized in the development stages by both design and manufacturing disciplines is rapid prototyping. Communication levels are intensified with the injection of functional models that are generated from a drawing. At the Marshall Space Flight Center, this discipline is utilized on a more frequent basis as a manner by which hardware may be tested for design and material compatibility.

  16. Simulink based behavioural modelling of a pulse oximeter for deployment in rapid development, prototyping and verification.

    PubMed

    Shokouhian, M; Morling, R C S; Kale, I

    2012-01-01

    The pulse oximeter is a well-known device for measuring the level of oxygen in blood. Since their invention, pulse oximeters have been under constant development in both aspects of hardware and software; however there are still unsolved problems that limit their performance [6], [7]. Many fresh algorithms and new design techniques are being suggested every year by industry and academic researchers which claim that they can improve accuracy of measurements [8], [9]. With the lack of an accurate computer-based behavioural model for pulse oximeters, the only way for evaluation of these newly developed systems and algorithms is through hardware implementation which can be both expensive and time consuming. This paper presents an accurate Simulink based behavioural model for a pulse oximeter that can be used by industry and academia alike working in this area, as an exploration as well as productivity enhancement tool during their research and development process. The aim of this paper is to introduce a new computer-based behavioural model which provides a simulation environment from which new ideas can be rapidly evaluated long before the real implementation.

  17. Rapid tooling by rapid prototyping: tools made by laser

    NASA Astrophysics Data System (ADS)

    Macht, Michael; Breitinger, Frank

    1996-08-01

    In view of the competitive situation on the international market, companies are being forced to develop products more rapidly and with less likelihood of errors occurring. In the recent past, product development has been greatly speeded up, above all by computer-aided methods. However, these are not entirely sufficient to achieve a further reduction in product development times. New manufacturing methods such as 'rapid prototyping' (RP) now make it possible to obtain not only computer models but also actual physical patterns in a very early development stage. As RP technologies gained in strength, a demand arose for prototypes in the actual material which it was intended to use for the production article. Using suitable process chains, it is now possible to produce components from various near-series plastics (for example by vacuum casting) and also from metals (e.g. by lost-wax casting or sand casting). At the Augsburg User Center run by Institute for Machine Tools and Industrial Management of Munich Technical University, processes for the rapid production of prototype tools which unite machining methods, RP technologies and molding techniques have therefore been developed.

  18. Application of Rapid Prototyping Pelvic Model for Patients with DDH to Facilitate Arthroplasty Planning: A Pilot Study.

    PubMed

    Xu, Jie; Li, Deng; Ma, Ruo-fan; Barden, Bertram; Ding, Yue

    2015-11-01

    Total hip arthroplasty (THA) is challenging in cases of osteoarthritis secondary to developmental dysplasia of the hip (DDH). Acetabular deficiency makes the positioning of the acetabular component difficult. Computer tomography based, patient-individual three dimensional (3-D) rapid prototype technology (RPT)-models were used to plan the placement of acetabular cup so that a surgeon was able to identify pelvic structures, assess the ideal extent of reaming and determine the size of cup after a reconstructive procedure. Intraclass correlation coefficients (ICCs) were used to analyze the agreement between the sizes of chosen components on the basis of preoperative planning and the actual sizes used in the operation. The use of the 3-D RPT-model facilitates the surgical procedures due to better planning and improved orientation. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. The accuracy of solid model and rapid prototype of prostheses in comparison to the digital CT image data

    NASA Astrophysics Data System (ADS)

    Suwandi, Agri; Kiswanto, Gandjar; Kusumaningsih, Widjajalaksmi; Soemardi, Tresna P.

    2017-02-01

    Prostheses are a derivative of biomedical products that have important things, which are: a design, size and bio compatible material. To produce optimum prostheses, safe and comfortable use, it would require design a model that fits the size of the patient's anatomy. In this paper describes the accuracy of solid model and rapid prototype of prostheses in comparison to the digital CT image data. Where the main parameters used as the reference measurement is digital CT image data. The data were analyzed using a statistical method to get the standard deviation of the comparison parameters of the data obtained, so that it can be known how the accuracy of the measurement results of each data.

  20. Rapid prototyping of clinical software assistants

    NASA Astrophysics Data System (ADS)

    Rexilius, Jan; Peitgen, Heinz-Otto

    2008-03-01

    Computer assistance in image-based diagnosis and therapy are continuously growing fields that have gained importance in several medical disciplines. Today, various free and commercial tools are available. However, only few are routinely applied in clinical practice. Especially tools that provide a flsupport of the whole design process from development and evaluation to the actual deployment in a clinical environment are missing. In this work, we introduce a categorization of the design process into different types and fields of application. To this end, we propose a novel framework that allows the development of software assistants that can be integrated into the design process of new algorithms and systems. We focus on the specific features of software prototypes that are valuable for engineers and clinicians, rather than on product development. An important aspect in this work is the categorization of the software design process into different components. Furthermore, we examine the interaction between these categories based on a new knowledge flow model. Finally, an encapsulation of these tasks within an application framework is proposed. We discuss general requirements and present a layered architecture. Several components for data- and workflow-management provide a generic functionality that can be customized on the developer and the user level. A flexible handling of is offered through the use of a visual programming and rapid prototyping platform. Currently, the framework is used in 15 software prototypes and as a basis of commercial products. More than 90 clinical partners all over the world work with these tools.

  1. Operative simulation of anterior clinoidectomy using a rapid prototyping model molded by a three-dimensional printer.

    PubMed

    Okonogi, Shinichi; Kondo, Kosuke; Harada, Naoyuki; Masuda, Hiroyuki; Nemoto, Masaaki; Sugo, Nobuo

    2017-05-15

    As the anatomical three-dimensional (3D) positional relationship around the anterior clinoid process (ACP) is complex, experience of many surgeries is necessary to understand anterior clinoidectomy (AC). We prepared a 3D synthetic image from computed tomographic angiography (CTA) and magnetic resonance imaging (MRI) data and a rapid prototyping (RP) model from the imaging data using a 3D printer. The objective of this study was to evaluate anatomical reproduction of the 3D synthetic image and intraosseous region after AC in the RP model. In addition, the usefulness of the RP model for operative simulation was investigated. The subjects were 51 patients who were examined by CTA and MRI before surgery. The size of the ACP, thickness and length of the optic nerve and artery, and intraosseous length after AC were measured in the 3D synthetic image and RP model, and reproducibility in the RP model was evaluated. In addition, 10 neurosurgeons performed AC in the completed RP models to investigate their usefulness for operative simulation. The RP model reproduced the region in the vicinity of the ACP in the 3D synthetic image, including the intraosseous region, at a high accuracy. In addition, drilling of the RP model was a useful operative simulation method of AC. The RP model of the vicinity of ACP, prepared using a 3D printer, showed favorable anatomical reproducibility, including reproduction of the intraosseous region. In addition, it was concluded that this RP model is useful as a surgical education tool for drilling.

  2. A neurosurgical simulation of skull base tumors using a 3D printed rapid prototyping model containing mesh structures.

    PubMed

    Kondo, Kosuke; Harada, Naoyuki; Masuda, Hiroyuki; Sugo, Nobuo; Terazono, Sayaka; Okonogi, Shinichi; Sakaeyama, Yuki; Fuchinoue, Yutaka; Ando, Syunpei; Fukushima, Daisuke; Nomoto, Jun; Nemoto, Masaaki

    2016-06-01

    Deep regions are not visible in three-dimensional (3D) printed rapid prototyping (RP) models prepared from opaque materials, which is not the case with translucent images. The objectives of this study were to develop an RP model in which a skull base tumor was simulated using mesh, and to investigate its usefulness for surgical simulations by evaluating the visibility of its deep regions. A 3D printer that employs binder jetting and is mainly used to prepare plaster models was used. RP models containing a solid tumor, no tumor, and a mesh tumor were prepared based on computed tomography, magnetic resonance imaging, and angiographic data for four cases of petroclival tumor. Twelve neurosurgeons graded the three types of RP model into the following four categories: 'clearly visible,' 'visible,' 'difficult to see,' and 'invisible,' based on the visibility of the internal carotid artery, basilar artery, and brain stem through a craniotomy performed via the combined transpetrosal approach. In addition, the 3D positional relationships between these structures and the tumor were assessed. The internal carotid artery, basilar artery, and brain stem and the positional relationships of these structures with the tumor were significantly more visible in the RP models with mesh tumors than in the RP models with solid or no tumors. The deep regions of PR models containing mesh skull base tumors were easy to visualize. This 3D printing-based method might be applicable to various surgical simulations.

  3. Rapid Prototyping in Technology Education.

    ERIC Educational Resources Information Center

    Flowers, Jim; Moniz, Matt

    2002-01-01

    Describes how technology education majors are using a high-tech model builder, called a fused deposition modeling machine, to develop their models directly from computer-based designs without any machining. Gives examples of applications in technology education. (JOW)

  4. Rapid Prototyping in Technology Education.

    ERIC Educational Resources Information Center

    Flowers, Jim; Moniz, Matt

    2002-01-01

    Describes how technology education majors are using a high-tech model builder, called a fused deposition modeling machine, to develop their models directly from computer-based designs without any machining. Gives examples of applications in technology education. (JOW)

  5. The creation and verification of cranial models using three-dimensional rapid prototyping technology in field of transnasal sphenoid endoscopy.

    PubMed

    Waran, Vicknes; Menon, Roshni; Pancharatnam, Devaraj; Rathinam, Alwin Kumar; Balakrishnan, Yuwaraj Kumar; Tung, Tan Su; Raman, Rajagopalan; Prepageran, Narayanan; Chandran, Hari; Rahman, Zainal Ariff Abdul

    2012-01-01

    Surgical navigation systems have been used increasingly in guiding complex ear, nose, and throat surgery. Although these are helpful, they are only beneficial intraoperatively; thus, the novice surgeon will not have the preoperative training or exposure that can be vital in complex procedures. In addition, there is a lack of reliable models to give surgeons hands-on training in performing such procedures. A technique using an industrial rapid prototyping process by three-dimensional (3D) printing was developed, from which accurate spatial models of the nasal cavity, paranasal sinuses (sphenoid sinus in particular), and intrasellar/pituitary pathology were produced, according to the parameters of an individual patient. Image-guided surgical (IGS) techniques on two different platforms were used during endoscopic transsphenoidal surgery to test and validate the anatomical accuracy of the sinus models by comparing the models with radiological images of the patient on IGS. It was possible to register, validate, and navigate accurately on these models using commonly available navigation stations, matching accurately the anatomy of the model to the IGS images. These 3D models can be reliably used for teaching/training and preoperative planning purposes.

  6. Application of the polystyrene model made by 3-D printing rapid prototyping technology for operation planning in revision lumbar discectomy.

    PubMed

    Li, Chao; Yang, Mingyuan; Xie, Yang; Chen, Ziqiang; Wang, Chuanfeng; Bai, Yushu; Zhu, Xiaodong; Li, Ming

    2015-05-01

    The objective was to evaluate the effectiveness of 3-D rapid prototyping technology in revision lumbar discectomy. 3-D rapid prototyping technology has not been reported in the treatment of revision lumbar discectomy. Patients with recurrent lumbar disc herniation who were preparing to undergo revision lumbar discectomy from a single center between January 2011 and 2013 were included in this analysis. Patients were divided into two groups. In group A, 3-D printing technology was used to create subject-specific lumbar vertebral models in the preoperative planning process. Group B underwent lumbar revision as usual. Preoperative and postoperative clinical outcomes were compared between groups included operation time, perioperative blood loss, postoperative complications, Oswestry Disability Index (ODI), Japan Orthopaedics Association (JOA) scores, and visual analogue scale (VAS) scores for back pain and leg pain. A total of 37 patients were included in this study (Group A = 15, Group B = 22). Group A had a significantly shorter operation time (106.53 ± 11.91 vs. 131.92 ± 10.81 min, P < 0.001) and significantly less blood loss (341.67 ± 49.45 vs. 466.77 ± 71.46 ml, P < 0.001). There was no difference between groups for complication rate. There were also no differences between groups for any clinical metric. Using the 3-D printing technology before revision lumbar discectomy may reduce the operation time and the perioperative blood loss. There does not appear to be a benefit to using the technology with respect to clinical outcomes. Future prospective studies are needed to further elucidate the efficacy of this emerging technology.

  7. Lumped Parameter Modeling for Rapid Vibration Response Prototyping and Test Correlation for Electronic Units

    NASA Technical Reports Server (NTRS)

    Van Dyke, Michael B.

    2013-01-01

    Present preliminary work using lumped parameter models to approximate dynamic response of electronic units to random vibration; Derive a general N-DOF model for application to electronic units; Illustrate parametric influence of model parameters; Implication of coupled dynamics for unit/board design; Demonstrate use of model to infer printed wiring board (PWB) dynamics from external chassis test measurement.

  8. Lumped Parameter Modeling for Rapid Vibration Response Prototyping and Test Correlation for Electronic Units

    NASA Technical Reports Server (NTRS)

    Van Dyke, Michael B.

    2013-01-01

    Present preliminary work using lumped parameter models to approximate dynamic response of electronic units to random vibration; Derive a general N-DOF model for application to electronic units; Illustrate parametric influence of model parameters; Implication of coupled dynamics for unit/board design; Demonstrate use of model to infer printed wiring board (PWB) dynamics from external chassis test measurement.

  9. Fluorescence Imaging and Streamline Visualization of Hypersonic Flow over Rapid Prototype Wind-Tunnel Models

    NASA Technical Reports Server (NTRS)

    Danehy, Paul M.; Alderfer, David W.; Inman, Jennifer A.; Berger, Karen T.; Buck, Gregory M.; Schwartz, Richard J.

    2008-01-01

    Reentry models for use in hypersonic wind tunnel tests were fabricated using a stereolithography apparatus. These models were produced in one day or less, which is a significant time savings compared to the manufacture of ceramic or metal models. The models were tested in the NASA Langley Research Center 31-Inch Mach 10 Air Tunnel. Only a few of the models survived repeated tests in the tunnel, and several failure modes of the models were identified. Planar laser-induced fluorescence (PLIF) of nitric oxide (NO) was used to visualize the flowfields in the wakes of these models. Pure NO was either seeded through tubes plumbed into the model or via a tube attached to the strut holding the model, which provided localized addition of NO into the model s wake through a porous metal cylinder attached to the end of the tube. Models included several 2- inch diameter Inflatable Reentry Vehicle Experiment (IRVE) models and 5-inch diameter Crew Exploration Vehicle (CEV) models. Various model configurations and NO seeding methods were used, including a new streamwise visualization method based on PLIF. Virtual Diagnostics Interface (ViDI) technology, developed at NASA Langley Research Center, was used to visualize the data sets in post processing. The use of calibration "dotcards" was investigated to correct for camera perspective and lens distortions in the PLIF images.

  10. Rapid Prototyping of Composite Structures

    NASA Technical Reports Server (NTRS)

    Colton, Jonathan S.

    1998-01-01

    This progress report for the project Rapid Production of Composite Structures covers the period from July 14, 1997 to June 30, 1998. It will present a short overview of the project, followed by the results to date and plans for the future. The goal of this research is to provide a minimum 100x reduction in the time required to produce arbitrary, laminated products without the need for a separate mold or an autoclave. It will accomplish this by developing the science underlying the rapid production of composite structures, specifically those of carbon fiber-epoxy materials. This scientific understanding will be reduced to practice in a demonstration device that will produce a part on the order of 12" by 12" by 6". Work in the past year has focussed on developing an understanding of the materials issues and of the machine design issues. Our initial goal was to use UV cureable resins to accomplish full cure on the machine. Therefore, we have centered our materials work around whether or not UV cureable resins will work. Currently, the answer seems to be that they will not work, because UV light cannot penetrate the carbon fibers, and because no "shadow" curing seems to occur. As a result, non-UV cureable resins are being investigated. This has resulted in a change in the machine design focus. We are now looking into a "dip and place" machine design, whereby a prepreg layer would have one side coated with a curing agent, and then would be placed onto the previous layer. This would lead to cure at the interface, but not to the top of the layer. The formulation of the resins to accomplish this task at room or slightly elevated temperatures is being investigated, as is the machine design needed to apply the curing agent and then cure or partially cure the part. A final, out-of-autoclave, post-cure may be needed with this strategy, as final cure on the machine may not be possible, as it was for the initial UV cure strategy. The remainder of this report details the progress

  11. Fluorescence Visualization of Hypersonic Flow over Rapid Prototype Wind-Tunnel Models

    NASA Technical Reports Server (NTRS)

    Alderfer, D. W.; Danehy, P. M.; Inma, J. A.; Berger, K. T.; Buck, G. M.; Schwartz, R J.

    2007-01-01

    Reentry models for use in hypersonic wind tunnel tests were fabricated using a stereolithography apparatus. These models were produced in one day or less, which is a significant time savings compared to the manufacture of ceramic or metal models. The models were tested in the NASA Langley Research Center 31-Inch Mach 10 Air Tunnel. Most of the models did not survive repeated tests in the tunnel, and several failure modes of the models were identified. Planar laser-induced fluorescence (PLIF) of nitric oxide (NO) was used to visualize the flowfields in the wakes of these models. Pure NO was either seeded through tubes plumbed into the model or via a tube attached to the strut holding the model, which provided localized addition of NO into the model s wake through a porous metal cylinder attached to the end of the tube. Models included several 2-inch diameter Inflatable Reentry Vehicle Experiment (IRVE) models and 5-inch diameter Crew Exploration Vehicle (CEV) models. Various configurations were studied including different sting placements relative to the models, different model orientations and attachment angles, and different NO seeding methods. The angle of attack of the models was also varied and the location of the laser sheet was scanned to provide three-dimensional flowfield information. Virtual Diagnostics Interface technology, developed at NASA Langley, was used to visualize the data sets in post processing. The use of calibration "dotcards" was investigated to correct for camera perspective and lens distortions in the PLIF images. Lessons learned and recommendations for future experiments are discussed.

  12. Rapid Prototyping of Composite Structures

    NASA Technical Reports Server (NTRS)

    Colton, Jonathan S.

    1998-01-01

    This final report for the project Rapid Production of Composite Structures covers the period from July 14, 1997 to September 30, 1998. It will present a short overview of the project, followed by the results to date and plans for the future. The goal of this research is to provide a minimum 100x reduction in the time required to produce arbitrary, laminated products without the need for a separate mold or an autoclave. It will accomplish this by developing the science underlying the rapid production of composite structures, specifically those of carbon fiber-epoxy materials. This scientific understanding will be reduced to practice in a demonstration device that will produce a part on the order of 12in. by 12in. by 6in. Work in the past year has focussed on developing an understanding of the materials issues and of the machine design issues. Our initial goal was to use UV cureable resins to accomplish full cure on the machine. Therefore, we have centered our materials work around whether or not UV cureable resins will work. Currently, the answer seems to be that they will not work, because UV light cannot penetrate the carbon fibers, and because no "shadow" curing seems to occur. As a result, non-UV cureable resins are being investigated. This has resulted in a change in the machine design focus. We are now looking into a "dip and place" machine design, whereby a prepreg layer would have one side coated with a curing agent, and then would be placed onto the previous layer. This would lead to cure at the interface, but not to the top of the layer. The formulation of the resins to accomplish this task at room or slightly elevated temperatures is being investigated, as is the machine design needed to apply the curing agent and then cure or partially cure the part. A final, out-of-autoclave, post-cure may be needed with this strategy, as final cure on the machine may not be possible, as it was for the initial UV cure strategy. The remainder of this report details the

  13. Rapid Prototyping of Composite Structures

    NASA Technical Reports Server (NTRS)

    Colton, Jonathan S.

    1998-01-01

    This final report for the project Rapid Production of Composite Structures covers the period from July 14, 1997 to September 30, 1998. It will present a short overview of the project, followed by the results to date and plans for the future. The goal of this research is to provide a minimum 100x reduction in the time required to produce arbitrary, laminated products without the need for a separate mold or an autoclave. It will accomplish this by developing the science underlying the rapid production of composite structures, specifically those of carbon fiber-epoxy materials. This scientific understanding will be reduced to practice in a demonstration device that will produce a part on the order of 12in. by 12in. by 6in. Work in the past year has focussed on developing an understanding of the materials issues and of the machine design issues. Our initial goal was to use UV cureable resins to accomplish full cure on the machine. Therefore, we have centered our materials work around whether or not UV cureable resins will work. Currently, the answer seems to be that they will not work, because UV light cannot penetrate the carbon fibers, and because no "shadow" curing seems to occur. As a result, non-UV cureable resins are being investigated. This has resulted in a change in the machine design focus. We are now looking into a "dip and place" machine design, whereby a prepreg layer would have one side coated with a curing agent, and then would be placed onto the previous layer. This would lead to cure at the interface, but not to the top of the layer. The formulation of the resins to accomplish this task at room or slightly elevated temperatures is being investigated, as is the machine design needed to apply the curing agent and then cure or partially cure the part. A final, out-of-autoclave, post-cure may be needed with this strategy, as final cure on the machine may not be possible, as it was for the initial UV cure strategy. The remainder of this report details the

  14. Rapid prototyping in aortic surgery.

    PubMed

    Bangeas, Petros; Voulalas, Grigorios; Ktenidis, Kiriakos

    2016-04-01

    3D printing provides the sequential addition of material layers and, thus, the opportunity to print parts and components made of different materials with variable mechanical and physical properties. It helps us create 3D anatomical models for the better planning of surgical procedures when needed, since it can reveal any complex anatomical feature. Images of abdominal aortic aneurysms received by computed tomographic angiography were converted into 3D images using a Google SketchUp free software and saved in stereolithography format. Using a 3D printer (Makerbot), a model made of polylactic acid material (thermoplastic filament) was printed. A 3D model of an abdominal aorta aneurysm was created in 138 min, while the model was a precise copy of the aorta visualized in the computed tomographic images. The total cost (including the initial cost of the printer) reached 1303.00 euros. 3D imaging and modelling using different materials can be very useful in cases when anatomical difficulties are recognized through the computed tomographic images and a tactile approach is demanded preoperatively. In this way, major complications during abdominal aorta aneurysm management can be predicted and prevented. Furthermore, the model can be used as a mould; the development of new, more biocompatible, less antigenic and individualized can become a challenge in the future.

  15. Autotransplantation of immature third molars using a computer-aided rapid prototyping model: a report of 4 cases.

    PubMed

    Jang, Ji-Hyun; Lee, Seung-Jong; Kim, Euiseong

    2013-11-01

    Autotransplantation of immature teeth can be an option for premature tooth loss in young patients as an alternative to immediately replacing teeth with fixed or implant-supported prostheses. The present case series reports 4 successful autotransplantation cases using computer-aided rapid prototyping (CARP) models with immature third molars. The compromised upper and lower molars (n = 4) of patients aged 15-21 years old were transplanted with third molars using CARP models. Postoperatively, the pulp vitality and the development of the roots were examined clinically and radiographically. The patient follow-up period was 2-7.5 years after surgery. The long-term follow-up showed that all of the transplants were asymptomatic and functional. Radiographic examination indicated that the apices developed continuously and the root length and thickness increased. The final follow-up examination revealed that all of the transplants kept the vitality, and the apices were fully developed with normal periodontal ligaments and trabecular bony patterns. Based on long-term follow-up observations, our 4 cases of autotransplantation of immature teeth using CARP models resulted in favorable prognoses. The CARP model assisted in minimizing the extraoral time and the possible Hertwig epithelial root sheath injury of the transplanted tooth. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  16. The Use of a Block Diagram Simulation Language for Rapid Model Prototyping

    NASA Technical Reports Server (NTRS)

    Whitlow, Johnathan E.; Engrand, Peter

    1996-01-01

    The research performed this summer was a continuation of work performed during the 1995 NASA/ASEE Summer Fellowship. The focus of the work was to expand previously generated predictive models for liquid oxygen (LOX) loading into the external fuel tank of the shuttle. The models which were developed using a block diagram simulation language known as VisSim, were evaluated on numerous shuttle flights and found to well in most cases. Once the models were refined and validated, the predictive methods were integrated into the existing Rockwell software propulsion advisory tool (PAT). Although time was not sufficient to completely integrate the models developed into PAT, the ability to predict flows and pressures in the orbiter section and graphically display the results was accomplished.

  17. A user-centered model for web site design: needs assessment, user interface design, and rapid prototyping.

    PubMed

    Kinzie, Mable B; Cohn, Wendy F; Julian, Marti F; Knaus, William A

    2002-01-01

    As the Internet continues to grow as a delivery medium for health information, the design of effective Web sites becomes increasingly important. In this paper, the authors provide an overview of one effective model for Web site design, a user-centered process that includes techniques for needs assessment, goal/task analysis, user interface design, and rapid prototyping. They detail how this approach was employed to design a family health history Web site, Health Heritage . This Web site helps patients record and maintain their family health histories in a secure, confidential manner. It also supports primary care physicians through analysis of health histories, identification of potential risks, and provision of health care recommendations. Visual examples of the design process are provided to show how the use of this model resulted in an easy-to-use Web site that is likely to meet user needs. The model is effective across diverse content arenas and is appropriate for applications in varied media.

  18. Integrating Rapid Prototyping into Graphic Communications

    ERIC Educational Resources Information Center

    Xu, Renmei; Flowers, Jim

    2015-01-01

    Integrating different science, technology, engineering, and mathematics (STEM) areas can help students learn and leverage both the equipment and expertise at a single school. In comparing graphic communications classes with classes that involve rapid prototyping (RP) technologies like 3D printing, there are sufficient similarities between goals,…

  19. Integrating Rapid Prototyping into Graphic Communications

    ERIC Educational Resources Information Center

    Xu, Renmei; Flowers, Jim

    2015-01-01

    Integrating different science, technology, engineering, and mathematics (STEM) areas can help students learn and leverage both the equipment and expertise at a single school. In comparing graphic communications classes with classes that involve rapid prototyping (RP) technologies like 3D printing, there are sufficient similarities between goals,…

  20. PyTrilinos Rapid Prototyping Package

    SciTech Connect

    Spotz, William F.

    2005-03-01

    PyTrilinos provides access to selected Trilinos packages from the python scripting language. This allows interactive and dynamic creation of Trilinos objects, rapid prototyping that does not require compilation, and "gluing" Trilinos scripts to other python modules, such as plotting, etc. The currently supported packages are Epetra, EpetraExt, and NOX.

  1. Investigation of the mechanical interaction of the trabecular core with an external shell using rapid prototype and finite element models.

    PubMed

    Mc Donnell, P; Harrison, N; Lohfeld, S; Kennedy, O; Zhang, Y; Mc Hugh, P E

    2010-01-01

    The mechanical properties of vertebral bone have been widely studied with the ultimate goal of improving fracture risk prediction. However, the mechanical interaction between the cortical shell and the trabecular core is not well understood. The objective of this study was to investigate this interaction and to determine what effect it has on the ultimate strength of the whole bone. This objective was achieved by compression testing rapid prototype (RP) models of cylindrical trabecular bone cores, with and without an integral surrounding shell and incorporating increasing levels of artificially induced bone loss. Corresponding finite element (FE) models were generated and the load sharing of the shell and trabecular core was analysed under linear elastic loading conditions. The results of the physical RP model tests and corresponding FE analyses indicated that there was a reinforcing effect between the cortical shell and the trabecular core for all models tested and that the reinforcing effect became relatively more important to the ultimate strength of the whole bone as the bone volume fraction of the trabecular core decreased. It was found that two mechanisms contributed to the reinforcing effect: (i) load transfer from the highly stressed shell into the connecting outer trabeculae of the core for the shelled model. This did not occur for the un-shelled model where the load dropped off at the outer unsupported trabeculae; (ii) the stiffening effect on the shell due to the support provided by the connecting struts of the trabecular core, which serves to inhibit bending and buckling behaviour in the shell under compression loading. It was found that the stiffening on the shell was the more dominant contributor to the overall reinforcing effect between the shell and the trabecular core.

  2. Combined use of rapid-prototyping model and surgical guide in correction of mandibular asymmetry malformation patients with normal occlusal relationship.

    PubMed

    Xu, Haisong; Zhang, Ce; Shim, Yoong Hoon; Li, Hongliang; Cao, Dejun

    2015-03-01

    The aim of this study is to discuss the application of rapid-prototyping model and surgical guide in the treatment of mandibular asymmetry malformation with normal occlusal relationship. Twenty-four mandibular asymmetry malformation patients with relatively normal occlusal relationship were included in this study. Surgical 3-dimensional rapid-prototyping mandibular models were made for all patients from the computed tomography (CT) DICOM data. The presurgical plan was designed on the model, and the surgical guiders for the osteotomy lines were manufactured. Genioplasty and/or mandibular osteotomy based on the presurgical plan were performed on these patients with the combined use of the rapid-prototyping model and surgical guides. All patients underwent postoperative CT scan and had at least 3-month follow-up. All patients were satisfied with the final results. According to the postoperative CT images and 3-month follow-up, all patients' mandibular asymmetry malformation was significantly improved, and the operation time was distinctly shortened relative to the conventional method. Rapid-prototyping model and surgical guide are viable auxiliary devices for the treatment of mandibular asymmetry malformation with relatively normal occlusal relationship. Combined use of them can make precise preoperative design, improve effects of operation, and shorten operating time.

  3. Review, Selection and Installation of a Rapid Prototype Machine

    NASA Technical Reports Server (NTRS)

    McEndree, Caryl

    2008-01-01

    The objective of this paper is to impress upon the reader the benefits and advantages of investing in rapid prototyping (additive manufacturing) technology thru the procurement of one or two new rapid prototyping machines and the creation of a new Prototype and Model Lab at the Kennedy Space Center (KSC). This new resource will be available to all of United Space Alliance, LLC (USA), enabling engineers from around the company to pursue a more effective means of communication and design with our co-workers, and our customer, the National Aeronautics and Space Administration (NASA). The Rapid Protoyping/3D printing industry mirrors the transition the CAD industry made several years ago, when companies were trying to justify the expenditure of converting to a 3D based system from a 2D based system. The advantages of using a 3D system seemed to be outweighed by the cost it would take to convert not only legacy 2D drawings into 3D models but the training of personnel to use the 3D CAD software. But the reality was that when a 3D CAD system is employed, it gives engineers a much greater ability to conceive new designs and the ability to engineer new tools and products much more effectively. Rapid Prototyping (RP) is the name given to a host of related technologies that are used to fabricate physical objects directly from Computer Aided Design (CAD) data sources. These methods are generally similar to each other in that they add and bond materials in a layer wise-fashion to form objects, instead of machining away material. The machines used in Rapid Prototyping are also sometimes referred to as Rapid Manufacturing machines due to the fact that some of the parts fabricated in a RP machine can be used as the finished product. The name "Rapid Prototyping" is really a misnomer. It is much more than prototypes and it is not always rapid.

  4. Rapid prototyping--when virtual meets reality.

    PubMed

    Beguma, Zubeda; Chhedat, Pratik

    2014-01-01

    Rapid prototyping (RP) describes the customized production of solid models using 3D computer data. Over the past decade, advances in RP have continued to evolve, resulting in the development of new techniques that have been applied to the fabrication of various prostheses. RP fabrication technologies include stereolithography (SLA), fused deposition modeling (FDM), computer numerical controlled (CNC) milling, and, more recently, selective laser sintering (SLS). The applications of RP techniques for dentistry include wax pattern fabrication for dental prostheses, dental (facial) prostheses mold (shell) fabrication, and removable dental prostheses framework fabrication. In the past, a physical plastic shape of the removable partial denture (RPD) framework was produced using an RP machine, and then used as a sacrificial pattern. Yet with the advent of the selective laser melting (SLM) technique, RPD metal frameworks can be directly fabricated, thereby omitting the casting stage. This new approach can also generate the wax pattern for facial prostheses directly, thereby reducing labor-intensive laboratory procedures. Many people stand to benefit from these new RP techniques for producing various forms of dental prostheses, which in the near future could transform traditional prosthodontic practices.

  5. Relatively Inexpensive Rapid Prototyping of Small Parts

    NASA Technical Reports Server (NTRS)

    Swan, Scott A.

    2003-01-01

    Parts with complex three-dimensional shapes and with dimensions up to 8 by 8 by 10 in. (20.3 by 20.3 by 25.4 cm) can be made as unitary pieces of a room-temperature-curing polymer, with relatively little investment in time and money, by a process now in use at Johnson Space Center. The process is one of a growing number of processes and techniques that are known collectively as the art of rapid prototyping. The main advantages of this process over other rapid-prototyping processes are greater speed and lower cost: There is no need to make paper drawings and take them to a shop for fabrication, and thus no need for the attendant paperwork and organizational delays. Instead, molds for desired parts are made automatically on a machine that is guided by data from a computer-aided design (CAD) system and can reside in an engineering office.

  6. Removable partial dentures: use of rapid prototyping.

    PubMed

    Lima, Julia Magalhaes Costa; Anami, Lilian Costa; Araujo, Rodrigo Maximo; Pavanelli, Carlos A

    2014-10-01

    The CAD/CAM technology associated with rapid prototyping (RP) is already widely used in the fabrication of all-ceramic fixed prostheses and in the biomedical area; however, the use of this technology for the manufacture of metal frames for removable dentures is new. This work reports the results of a literature review conducted on the use of CAD/CAM and RP in the manufacture of removable partial dentures. © 2014 by the American College of Prosthodontists.

  7. Laser-assisted rapid prototyping in Japan

    NASA Astrophysics Data System (ADS)

    Kathuria, Yash P.

    2002-04-01

    In the recent past years, developments in the rapid prototyping of various parts have taken new dynamic turns in manufacturing technology. Besides the use of new materials, unrelenting demands for the downsizing of miniature components in the micro-domain have expanded the application area of the rapid prototype product. Their requirements with reduced time lag have forced the manufacturers to adopt and develop innovative techniques which meet these demands. In order to overcome this problem, several techniques, predominantly laser stereolithography, have successfully been used in Japan for the past several years to generate a complex micro-/macro part of polymer resin based in two- or three-dimensional domains. The main disadvantage of this process is that they consist of two or more steps for producing metallic/metal-matrix composite microstructures. But recently developed new technologies of selective laser sintering/generating and ballistic particles manufacturing processes offer the possibility of the direct generation of these microstructures in a single step process. The last two processes actually have limitations on the feature size produced, due to the minimum size of the molten droplet. But the selective laser sintering technique can bind the particles by melting together at the interfacial grain contact area only and thus producing smaller feature sizes. Based upon these techniques, the present paper aims to review the current status and the future prospective of laser assisted rapid prototyping in Japan.

  8. Rapid prototyping of scaphoid and lunate bones.

    PubMed

    Gittard, Shaun D; Narayan, Roger J; Lusk, Jason; Morel, Pierre; Stockmans, Filip; Ramsey, Michael; Laverde, Claire; Phillips, Jack; Monteiro-Riviere, Nancy A; Ovsianikov, Aleksandr; Chichkov, Boris N

    2009-01-01

    In this study, a novel rapid prototyping technology was used to fabricate scaphoid and lunate bone prostheses, two carpal bones that are prone to avascular necrosis. Carpal prostheses were fabricated with an Envisiontec Perfactory SXGA stereolithography system using Envisiontec eShell 200 photocurable polymer. Fabrication was guided using 3-D models, which were generated using Mimics software (Materialise NV, Leuven, Belgium) from patient computer tomography data. The prostheses were fabricated in a layer-by-layer manner; approximately 50-microm thick layers were observed in the prostheses. Hardness and Young's modulus values of polymerized eShell 200 material were 93.8 +/- 7.25 MPa and 3050 +/- 90 MPa, respectively. The minimum compressive force required for fracture was 1360 N for the scaphoid prosthesis and 1248 N for the lunate prosthesis. Polymerized Envisiontec eShell material exhibited high human neonatal epidermal keratinocyte cell viability rate in an MTT assay. The results of this study indicate that small bone prostheses fabricated by stereolithography using eShell 200 polymer may have suitable geometry, mechanical properties, and cytocompatibility properties for in vivo use.

  9. Rapid Prototyping in Orthopaedic Surgery: A User's Guide

    PubMed Central

    Frame, Mark; Huntley, James S.

    2012-01-01

    Rapid prototyping (RP) is applicable to orthopaedic problems involving three dimensions, particularly fractures, deformities, and reconstruction. In the past, RP has been hampered by cost and difficulties accessing the appropriate expertise. Here we outline the history of rapid prototyping and furthermore a process using open-source software to produce a high fidelity physical model from CT data. This greatly mitigates the expense associated with the technique, allowing surgeons to produce precise models for preoperative planning and procedure rehearsal. We describe the method with an illustrative case. PMID:22666160

  10. Rapid Prototyping Of Layered Composite Parts

    NASA Technical Reports Server (NTRS)

    Wolff, Edwin D.

    1992-01-01

    Numerically controlled cutting accelerates fabrication of layers. Proposed method derived from stereoscopic lithography. CATIA or CAEDS computer program used to generate three-dimensional mathematical model of prototype part. In model, geometry of part specified in layers, as in stereoscopic lithography. Model data for each layer fed to computer-numerically-controlled ultrasonic cutting machine. Sheet of prepreg (uncured composite material) of specified layer thickness placed in machine and cut, under control of model data, to specified shape of layer.

  11. Rapid Prototyping Of Layered Composite Parts

    NASA Technical Reports Server (NTRS)

    Wolff, Edwin D.

    1992-01-01

    Numerically controlled cutting accelerates fabrication of layers. Proposed method derived from stereoscopic lithography. CATIA or CAEDS computer program used to generate three-dimensional mathematical model of prototype part. In model, geometry of part specified in layers, as in stereoscopic lithography. Model data for each layer fed to computer-numerically-controlled ultrasonic cutting machine. Sheet of prepreg (uncured composite material) of specified layer thickness placed in machine and cut, under control of model data, to specified shape of layer.

  12. Development of three-dimensional hollow elastic model for cerebral aneurysm clipping simulation enabling rapid and low cost prototyping.

    PubMed

    Mashiko, Toshihiro; Otani, Keisuke; Kawano, Ryutaro; Konno, Takehiko; Kaneko, Naoki; Ito, Yumiko; Watanabe, Eiju

    2015-03-01

    We developed a method for fabricating a three-dimensional hollow and elastic aneurysm model useful for surgical simulation and surgical training. In this article, we explain the hollow elastic model prototyping method and report on the effects of applying it to presurgical simulation and surgical training. A three-dimensional printer using acrylonitrile-butadiene-styrene as a modeling material was used to produce a vessel model. The prototype was then coated with liquid silicone. After the silicone had hardened, the acrylonitrile-butadiene-styrene was melted with xylene and removed, leaving an outer layer as a hollow elastic model. Simulations using the hollow elastic model were performed in 12 patients. In all patients, the clipping proceeded as scheduled. The surgeon's postoperative assessment was favorable in all cases. This method enables easy fabrication at low cost. Simulation using the hollow elastic model is thought to be useful for understanding of three-dimensional aneurysm structure. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Rapid Prototyping Integrated With Nondestructive Evaluation and Finite Element Analysis

    NASA Technical Reports Server (NTRS)

    Abdul-Aziz, Ali; Baaklini, George Y.

    2001-01-01

    Most reverse engineering approaches involve imaging or digitizing an object then creating a computerized reconstruction that can be integrated, in three dimensions, into a particular design environment. Rapid prototyping (RP) refers to the practical ability to build high-quality physical prototypes directly from computer aided design (CAD) files. Using rapid prototyping, full-scale models or patterns can be built using a variety of materials in a fraction of the time required by more traditional prototyping techniques (refs. 1 and 2). Many software packages have been developed and are being designed to tackle the reverse engineering and rapid prototyping issues just mentioned. For example, image processing and three-dimensional reconstruction visualization software such as Velocity2 (ref. 3) are being used to carry out the construction process of three-dimensional volume models and the subsequent generation of a stereolithography file that is suitable for CAD applications. Producing three-dimensional models of objects from computed tomography (CT) scans is becoming a valuable nondestructive evaluation methodology (ref. 4). Real components can be rendered and subjected to temperature and stress tests using structural engineering software codes. For this to be achieved, accurate high-resolution images have to be obtained via CT scans and then processed, converted into a traditional file format, and translated into finite element models. Prototyping a three-dimensional volume of a composite structure by reading in a series of two-dimensional images generated via CT and by using and integrating commercial software (e.g. Velocity2, MSC/PATRAN (ref. 5), and Hypermesh (ref. 6)) is being applied successfully at the NASA Glenn Research Center. The building process from structural modeling to the analysis level is outlined in reference 7. Subsequently, a stress analysis of a composite cooling panel under combined thermomechanical loading conditions was performed to validate

  14. Integration of rapid prototyping into design and manufacturing

    SciTech Connect

    Atwood, C.L.; McCarty, G.D.; Pardo, B.T.

    1993-04-01

    The introduction of rapid prototyping machines into the market place promises to revolutionize the process of producing prototype parts with production-like quality. In the age of concurrent engineering and agile manufacturing, it is necessary to exploit applicable new technologies as soon as they become available. The driving force behind integrating these evolutionary processes into the design and manufacture of prototype parts is the need to reduce lead times and fabrication costs improve efficiency, and increase flexibility without sacrificing quality. Sandia Utilizes stereolithography and selective laser sintering capabilities to support internal design and manufacturing efforts. Stereolithography (SLA) is used in the design iteration process to produce proof-of-concept models, hands-on models for design reviews, fit check models, visual aids for manufacturing, and functional parts in assemblies. Selective laser sintering (SLS) is used to produce wax patterns for the lost wax process of investment casting in support of an internal Sandia National Laboratories program called FASTCAST which integrates experimental and computational technologies into the investment casting process. This presentation will provide a brief overview of the SLA and SLS processes and address our experiences with these technologies from the standpoints of application, accuracy, surface finish, and feature definition. Also presented will be several examples of prototype parts manufactured by the stereolithography and selective laser sintering rapid prototyping machines.

  15. Integration of rapid prototyping into design and manufacturing

    SciTech Connect

    Atwood, C.L.; McCarty, G.D.; Pardo, B.T.; Bryce, E.A.

    1993-10-01

    The introduction of rapid prototyping machines into the marketplace promises to revolutionize the process of producing prototype parts with production-like quality. In the age of concurrent engineering and agile manufacturing, it is necessary to exploit applicable new technologies as soon as they become available. The driving force behind integrating these evolutionary processes into the design and manufacture of prototype parts is the need to reduce lead times and fabrication costs, improve efficiency, and increase flexibility without sacrificing quality. Sandia utilizes Stereolithography (SL) and Selective Laser Sintering (SLS) capabilities to support internal design and manufacturing efforts. SL is used in the design iteration process to produce proof-of-concept models, hands-on models for design reviews, fit-check models, visual aids for manufacturing, and functional parts in assemblies. SLS is used to produce wax patterns for the lost wax process of investment casting in support of an internal Sandia National Laboratories program called FASTCAST which integrates experimental and computational technologies into the investment casting process. This presentation will provide a brief overview of the SL and SLS processes and address our experiences with these technologies from the standpoints of application, accuracy, surface finish, and feature definition. Also presented will be several examples of prototype parts manufactured by the Stereolithography and Selective Laser Sintering rapid prototyping machines.

  16. Rapid 2-axis scanning lidar prototype

    NASA Astrophysics Data System (ADS)

    Hartsell, Daryl; LaRocque, Paul E.; Tripp, Jeffrey

    2016-10-01

    The rapid 2-axis scanning lidar prototype was developed to demonstrate high-precision single-pixel linear-mode lidar performance. The lidar system is a combined integration of components from various commercial products allowing for future customization and performance enhancements. The intent of the prototype scanner is to demonstrate current stateof- the-art high-speed linear scanning technologies. The system consists of two pieces: the sensor head and control unit. The senor head can be installed up to 4 m from the control box and houses the lidar scanning components and a small RGB camera. The control unit houses the power supplies and ranging electronics necessary for operating the electronics housed inside the sensor head. This paper will discuss the benefits of a 2-axis scanning linear-mode lidar system, such as range performance and a userselectable FOV. Other features include real-time processing of 3D image frames consisting of up to 200,000 points per frame.

  17. The application of rapid prototyping technique in chin augmentation.

    PubMed

    Li, Min; Lin, Xin; Xu, Yongchen

    2010-04-01

    This article discusses the application of computer-aided design and rapid prototyping techniques in prosthetic chin augmentation for mild microgenia. Nine cases of mild microgenia underwent an electrobeam computer tomography scan. Then we performed three-dimensional reconstruction and operative design using computer software. According to the design, we determined the shape and size of the prostheses and made an individualized prosthesis for each chin augmentation with the rapid prototyping technique. With the application of computer-aided design and a rapid prototyping technique, we could determine the shape, size, and embedding location accurately. Prefabricating the individual prosthesis model is useful in improving the accuracy of treatment. In the nine cases of mild microgenia, three received a silicone implant, four received an ePTFE implant, and two received a Medpor implant. All patients were satisfied with the results. During follow-up at 6-12 months, all patients remained satisfied. The application of computer-aided design and rapid prototyping techniques can offer surgeons the ability to design an individualized ideal prosthesis for each patient.

  18. Rapid prototyping-assisted maxillofacial reconstruction.

    PubMed

    Peng, Qian; Tang, Zhangui; Liu, Ousheng; Peng, Zhiwei

    2015-05-01

    Rapid prototyping (RP) technologies have found many uses in dentistry, and especially oral and maxillofacial surgery, due to its ability to promote product development while at the same time reducing cost and depositing a part of any degree of complexity theoretically. This paper provides an overview of RP technologies for maxillofacial reconstruction covering both fundamentals and applications of the technologies. Key fundamentals of RP technologies involving the history, characteristics, and principles are reviewed. A number of RP applications to the main fields of oral and maxillofacial surgery, including restoration of maxillofacial deformities and defects, reduction of functional bone tissues, correction of dento-maxillofacial deformities, and fabrication of maxillofacial prostheses, are discussed. The most remarkable challenges for development of RP-assisted maxillofacial surgery and promising solutions are also elaborated.

  19. 3D measurement for rapid prototyping

    NASA Astrophysics Data System (ADS)

    Albrecht, Peter; Lilienblum, Tilo; Sommerkorn, Gerd; Michaelis, Bernd

    1996-08-01

    Optical 3-D measurement is an interesting approach for rapid prototyping. On one hand it's necessary to get the 3-D data of an object and on the other hand it's necessary to check the manufactured object (quality checking). Optical 3-D measurement can realize both. Classical 3-D measurement procedures based on photogrammetry cause systematic errors at strongly curved surfaces or steps in surfaces. One possibility to reduce these errors is to calculate the 3-D coordinates from several successively taken images. Thus it's possible to get higher spatial resolution and to reduce the systematic errors at 'problem surfaces.' Another possibility is to process the measurement values by neural networks. A modified associative memory smoothes and corrects the calculated 3-D coordinates using a-priori knowledge about the measurement object.

  20. The application of rapid prototyping in prosthodontics.

    PubMed

    Sun, Jian; Zhang, Fu-Qiang

    2012-12-01

    Dentists have used rapid prototyping (RP) techniques in the fields of oral maxillofacial surgery simulation and implantology. With new research emerging for molding materials and the forming process of RP techniques, this method is becoming more attractive in dental prosthesis fabrication; however, few researchers have published material on the RP technology of prosthesis pattern fabrication. This article reviews and discusses the application of RP techniques for prosthodontics including: (1) fabrication of wax pattern for the dental prosthesis, (2) dental (facial) prosthesis mold (shell) fabrication, (3) dental metal prosthesis fabrication, and (4) zirconia prosthesis fabrication. Many people could benefit from this new technology through various forms of dental prosthesis production. Traditional prosthodontic practices could also be changed by RP techniques in the near future. © 2012 by the American College of Prosthodontists.

  1. Rapid prototyping of ossicular replacement prostheses

    NASA Astrophysics Data System (ADS)

    Ovsianikov, A.; Chichkov, B.; Adunka, O.; Pillsbury, H.; Doraiswamy, A.; Narayan, R. J.

    2007-05-01

    Materials used in ossicular replacement prostheses must demonstrate appropriate biological compatibility, acoustic transmission, stability, and stiffness properties. Prostheses prepared using Teflon ®, titanium, Ceravital and other conventional materials have demonstrated several problems, including migration, perforation of the tympanic membrane, difficulty in shaping the prostheses, and reactivity with the surrounding tissues. We have used two-photon polymerization for rapid prototyping of Ormocer ® middle-ear bone replacement prostheses. Ormocer ® surfaces fabricated using two-photon polymerization exhibited acceptable cell viability and cell growth profiles. The Ormocer ® prosthesis was able to be inserted and removed from the site of use in the frozen human head without fracture. Our results demonstrate that two-photon polymerization is able to create ossicular replacement prostheses and other medical devices with a larger range of sizes, shapes and materials than other microfabrication techniques.

  2. The Mississippi Research Consortium Rapid Prototyping Capability Overview

    NASA Astrophysics Data System (ADS)

    Moorhead, R.; Haupt, T.; Anantharaj, V.; O'Hara, C.; Aanstoos, J.

    2006-12-01

    Mississippi State University and the University of Mississippi, along with several partners, are exploiting a systems engineering approach to develop and deploy a computational Rapid Prototyping Capability (RPC). This RPC will be used to evaluate research results, predominantly measurements and models, to determine appropriate capabilities by which societal benefits can be obtained via routine operational utilization. This RPC will facilitate science experiments that access, process, and assimilate terascale data from distributed and heterogeneous sources by using numerical models that scale from the desktop to high- performance platforms. The science experiments can be rapidly prototyped in order to evaluate the suitability of data, algorithms and models. The RPC experiments are designed to characterize uncertainties involved in the data, models, and decision making process while maintaining scientific rigor through the entire process. This approach helps identify scientific and logistical risks earlier in the process so that they can be appropriately addressed in a timely manner to minimize risk. This talk or poster will focus on (a) the architecture and cyber-infrastructure we are deploying under NASA, NOAA, and Navy funding for rapid prototyping capabilities to support applied research; (b) the integration of model and data frameworks; and (c) RPC concepts for the design and execution of science experiments.

  3. Rapid Prototyping of Patterned Multifunctional Nanostructures

    SciTech Connect

    FAN,HONGYOU; LU,YUNFENG; LOPEZ,GABRIEL P.; BRINKER,C. JEFFREY

    2000-07-18

    The ability to engineer ordered arrays of objects on multiple length scales has potential for applications such as microelectronics, sensors, wave guides, and photonic lattices with tunable band gaps. Since the invention of surfactant templated mesoporous sieves in 1992, great progress has been made in controlling different mesophases in the form of powders, particles, fibers, and films. To date, although there have been several reports of patterned mesostructures, materials prepared have been limited to metal oxides with no specific functionality. For many of the envisioned applications of hierarchical materials in micro-systems, sensors, waveguides, photonics, and electronics, it is necessary to define both form and function on several length scales. In addition, the patterning strategies utilized so far require hours or even days for completion. Such slow processes are inherently difficult to implement in commercial environments. The authors present a series of new methods of producing patterns within seconds. Combining sol-gel chemistry, Evaporation-Induced Self-Assembly (EISA), and rapid prototyping techniques like pen lithography, ink-jet printing, and dip-coating on micro-contact printed substrates, they form hierarchically organized silica structures that exhibit order and function on multiple scales: on the molecular scale, functional organic moieties are positioned on pore surfaces, on the mesoscale, mono-sized pores are organized into 1-, 2-, or 3-dimensional networks, providing size-selective accessibility from the gas or liquid phase, and on the macroscale, 2-dimensional arrays and fluidic or photonic systems may be defined. These rapid patterning techniques establish for the first time a link between computer-aided design and rapid processing of self-assembled nanostructures.

  4. Manufacturing Implant Supported Auricular Prostheses by Rapid Prototyping Techniques

    PubMed Central

    Karatas, Meltem Ozdemir; Cifter, Ebru Demet; Ozenen, Didem Ozdemir; Balik, Ali; Tuncer, Erman Bulent

    2011-01-01

    Maxillofacial prostheses are usually fabricated on the models obtained following the impression procedures. Disadvantages of conventional impression techniques used in production of facial prosthesis are deformation of soft tissues caused by impression material and disturbance of the patient due to. Additionally production of prosthesis by conventional methods takes longer time. Recently, rapid prototyping techniques have been developed for extraoral prosthesis in order to reduce these disadvantages of conventional methods. Rapid prototyping technique has the potential to simplify the procedure and decrease the laboratory work required. It eliminates the need for measurement impression procedures and preparation of wax model to be performed by prosthodontists themselves In the near future this technology will become a standard for fabricating maxillofacial prostheses. PMID:21912504

  5. Manufacturing implant supported auricular prostheses by rapid prototyping techniques.

    PubMed

    Karatas, Meltem Ozdemir; Cifter, Ebru Demet; Ozenen, Didem Ozdemir; Balik, Ali; Tuncer, Erman Bulent

    2011-08-01

    Maxillofacial prostheses are usually fabricated on the models obtained following the impression procedures. Disadvantages of conventional impression techniques used in production of facial prosthesis are deformation of soft tissues caused by impression material and disturbance of the patient due to. Additionally production of prosthesis by conventional methods takes longer time. Recently, rapid prototyping techniques have been developed for extraoral prosthesis in order to reduce these disadvantages of conventional methods. Rapid prototyping technique has the potential to simplify the procedure and decrease the laboratory work required. It eliminates the need for measurement impression procedures and preparation of wax model to be performed by prosthodontists themselves In the near future this technology will become a standard for fabricating maxillofacial prostheses.

  6. Rapid prototyping fabrication of focused ultrasound transducers.

    PubMed

    Kim, Yohan; Maxwell, Adam D; Hall, Timothy L; Xu, Zhen; Lin, Kuang-Wei; Cain, Charles A

    2014-09-01

    Rapid prototyping (RP) fabrication techniques are currently widely used in diverse industrial and medical fields, providing substantial advantages in development time and costs in comparison to more traditional manufacturing processes. This paper presents a new method for the fabrication of high-intensity focused ultrasound transducers using RP technology. The construction of a large-aperture hemispherical transducer designed by computer software is described to demonstrate the process. The transducer was conceived as a modular design consisting of 32 individually focused 50.8-mm (2-in) PZT-8 element modules distributed in a 300-mm hemispherical scaffold with a geometric focus of 150 mm. The entire structure of the array, including the module housings and the hemispherical scaffold was fabricated through a stereolithography (SLA) system using a proprietary photopolymer. The PZT elements were bonded to the lenses through a quarter-wave tungsten-epoxy matching layer developed in-house specifically for this purpose. Modules constructed in this manner displayed a high degree of electroacoustic consistency, with an electrical impedance mean and standard deviation of 109 ± 10.2 Ω for the 32 elements. Time-of-flight measurements for individually pulsed modules mounted on the hemispherical scaffold showed that all pulses arrived at the focus within a 350 ns range, indicating a good degree of element alignment. Pressure profile measurements of the fully assembled transducer also showed close agreement with simulated results. The measured focal beam FWHM dimensions were 1.9 × 4.0 mm (1.9 × 3.9 mm simulated) in the transversal and axial directions respectively. Total material expenses associated with the construction of the transducer were approximately 5000 USD (as of 2011). The versatility and lower fabrication costs afforded by RP methods may be beneficial in the development of complex transducer geometries suitable for a variety of research and clinical applications.

  7. Implementation of Additive Rapid Prototyping on Retrofit CNC Mill

    USDA-ARS?s Scientific Manuscript database

    Freeform fabrication techniques are gaining popularity as a means of making parts. Layered additive methods are associated with rapid prototyping. Many rapid prototyping methods are commercially proprietary and may cost thousands of dollars. Using a retrofit CNC mill for layered fabrication and C...

  8. Rapid prototyping technology and its application in bone tissue engineering.

    PubMed

    Yuan, Bo; Zhou, Sheng-Yuan; Chen, Xiong-Sheng

    Bone defects arising from a variety of reasons cannot be treated effectively without bone tissue reconstruction. Autografts and allografts have been used in clinical application for some time, but they have disadvantages. With the inherent drawback in the precision and reproducibility of conventional scaffold fabrication techniques, the results of bone surgery may not be ideal. This is despite the introduction of bone tissue engineering which provides a powerful approach for bone repair. Rapid prototyping technologies have emerged as an alternative and have been widely used in bone tissue engineering, enhancing bone tissue regeneration in terms of mechanical strength, pore geometry, and bioactive factors, and overcoming some of the disadvantages of conventional technologies. This review focuses on the basic principles and characteristics of various fabrication technologies, such as stereolithography, selective laser sintering, and fused deposition modeling, and reviews the application of rapid prototyping techniques to scaffolds for bone tissue engineering. In the near future, the use of scaffolds for bone tissue engineering prepared by rapid prototyping technology might be an effective therapeutic strategy for bone defects.

  9. Rapid prototyping technology and its application in bone tissue engineering*

    PubMed Central

    YUAN, Bo; ZHOU, Sheng-yuan; CHEN, Xiong-sheng

    2017-01-01

    Bone defects arising from a variety of reasons cannot be treated effectively without bone tissue reconstruction. Autografts and allografts have been used in clinical application for some time, but they have disadvantages. With the inherent drawback in the precision and reproducibility of conventional scaffold fabrication techniques, the results of bone surgery may not be ideal. This is despite the introduction of bone tissue engineering which provides a powerful approach for bone repair. Rapid prototyping technologies have emerged as an alternative and have been widely used in bone tissue engineering, enhancing bone tissue regeneration in terms of mechanical strength, pore geometry, and bioactive factors, and overcoming some of the disadvantages of conventional technologies. This review focuses on the basic principles and characteristics of various fabrication technologies, such as stereolithography, selective laser sintering, and fused deposition modeling, and reviews the application of rapid prototyping techniques to scaffolds for bone tissue engineering. In the near future, the use of scaffolds for bone tissue engineering prepared by rapid prototyping technology might be an effective therapeutic strategy for bone defects. PMID:28378568

  10. Reconstruction of large cranial defects with poly-methyl-methacrylate (PMMA) using a rapid prototyping model and a new technique for intraoperative implant modeling.

    PubMed

    Unterhofer, Claudia; Wipplinger, Christoph; Verius, Michael; Recheis, Wolfgang; Thomé, Claudius; Ortler, Martin

    Reconstruction of large cranial defects after craniectomy can be accomplished by free-hand poly-methyl-methacrylate (PMMA) or industrially manufactured implants. The free-hand technique often does not achieve satisfactory cosmetic results but is inexpensive. In an attempt to combine the accuracy of specifically manufactured implants with low cost of PMMA. Forty-six consecutive patients with large skull defects after trauma or infection were retrospectively analyzed. The defects were reconstructed using computer-aided design/computer-aided manufacturing (CAD/CAM) techniques. The computer file was imported into a rapid prototyping (RP) machine to produce an acrylonitrile-butadiene-styrene model (ABS) of the patient's bony head. The gas-sterilized model was used as a template for the intraoperative modeling of the PMMA cranioplasty. Thus, not the PMMA implant was generated by CAD/CAM technique but the model of the patients head to easily form a well-fitting implant. Cosmetic outcome was rated on a six-tiered scale by the patients after a minimum follow-up of three months. The mean size of the defect was 74.36cm(2). The implants fitted well in all patients. Seven patients had a postoperative complication and underwent reoperation. Mean follow-up period was 41 months (range 2-91 months). Results were excellent in 42, good in three and not satisfactory in one patient. Costs per implant were approximately 550 Euros. PMMA implants fabricated in-house by direct molding using a bio-model of the patients bony head are easily produced, fit properly and are inexpensive compared to cranial implants fabricated with other RP or milling techniques. Copyright © 2017 Polish Neurological Society. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  11. Rapid Production of Composite Prototype Hardware

    NASA Technical Reports Server (NTRS)

    DeLay, T. K.

    2000-01-01

    The objective of this research was to provide a mechanism to cost-effectively produce composite hardware prototypes. The task was to take a hands-on approach to developing new technologies that could benefit multiple future programs.

  12. Rapid prototyping of patterned functional nanostructures

    SciTech Connect

    FAN,HONGYOU; LU,YUNFENG; STUMP,AARON; REED,SCOTT T.; BAER,THOMAS A.; SCHUNK,P. RANDALL; PEREZ-LUNA,VICTOR; LOPEZ,GABRIEL P.; BRINKER,C. JEFFREY

    2000-02-09

    Living systems exhibit form and function on multiple length scales, and the prospect of imparting life-like qualities to man-made materials has inspired many recent efforts to devise hierarchical materials assembly strategies. For example, Yang et al. grew surfactant-templated mesoporous silica on hydrophobic patterns prepared by micro-contact printing {micro}CP{sup 3}. Trau et al. formed oriented mesoporous silica patterns, using a micro-molding in capillaries MIMIC technique, and Yang et al. combined MIMIC, polystyrene sphere templating, and surfactant-templating to create oxides with three levels of structural order. Overall, great progress has been made to date in controlling structure on scales ranging from several nanometers to several micrometers. However, materials prepared have been limited to oxides with no specific functionality, whereas for many of the envisioned applications of hierarchical materials in micro-systems, sensors, waveguides, photonics, and electronics, it is necessary to define both form and function on several length scales. In addition, the patterning strategies employed thus far require hours or even days for completion. Such slow processes are inherently difficult to implement in commercial environments. The authors have combined evaporation-induced (silica/surfactant) self-assembly EISA with rapid prototyping techniques like pen lithography, ink-jet printing, and dip-coating on micro-contact printed substrates to form hierarchically organized structures in seconds. In addition, by co-condensation of tetrafunctional silanes (Si(OR){sub 4}) with tri-functional organosilanes ((RO){sub 3}SiR{prime}){sup 12--14} or by inclusion of organic additives, the authors have selectively derivatized the silica framework with functional R{prime} ligands or molecules. The resulting materials exhibit form and function on multiple length scales: on the molecular scale, functional organic moieties are positioned on pore surfaces, on the mesoscale

  13. Accuracy and precision of polyurethane dental arch models fabricated using a three-dimensional subtractive rapid prototyping method with an intraoral scanning technique.

    PubMed

    Kim, Jae-Hong; Kim, Ki-Baek; Kim, Woong-Chul; Kim, Ji-Hwan; Kim, Hae-Young

    2014-03-01

    This study aimed to evaluate the accuracy and precision of polyurethane (PUT) dental arch models fabricated using a three-dimensional (3D) subtractive rapid prototyping (RP) method with an intraoral scanning technique by comparing linear measurements obtained from PUT models and conventional plaster models. Ten plaster models were duplicated using a selected standard master model and conventional impression, and 10 PUT models were duplicated using the 3D subtractive RP technique with an oral scanner. Six linear measurements were evaluated in terms of x, y, and z-axes using a non-contact white light scanner. Accuracy was assessed using mean differences between two measurements, and precision was examined using four quantitative methods and the Bland-Altman graphical method. Repeatability was evaluated in terms of intra-examiner variability, and reproducibility was assessed in terms of inter-examiner and inter-method variability. The mean difference between plaster models and PUT models ranged from 0.07 mm to 0.33 mm. Relative measurement errors ranged from 2.2% to 7.6% and intraclass correlation coefficients ranged from 0.93 to 0.96, when comparing plaster models and PUT models. The Bland-Altman plot showed good agreement. The accuracy and precision of PUT dental models for evaluating the performance of oral scanner and subtractive RP technology was acceptable. Because of the recent improvements in block material and computerized numeric control milling machines, the subtractive RP method may be a good choice for dental arch models.

  14. Rapid prototyping for biomedical engineering: current capabilities and challenges.

    PubMed

    Lantada, Andrés Díaz; Morgado, Pilar Lafont

    2012-01-01

    A new set of manufacturing technologies has emerged in the past decades to address market requirements in a customized way and to provide support for research tasks that require prototypes. These new techniques and technologies are usually referred to as rapid prototyping and manufacturing technologies, and they allow prototypes to be produced in a wide range of materials with remarkable precision in a couple of hours. Although they have been rapidly incorporated into product development methodologies, they are still under development, and their applications in bioengineering are continuously evolving. Rapid prototyping and manufacturing technologies can be of assistance in every stage of the development process of novel biodevices, to address various problems that can arise in the devices' interactions with biological systems and the fact that the design decisions must be tested carefully. This review focuses on the main fields of application for rapid prototyping in biomedical engineering and health sciences, as well as on the most remarkable challenges and research trends.

  15. 3D Rapid Prototyping for Otolaryngology—Head and Neck Surgery: Applications in Image-Guidance, Surgical Simulation and Patient-Specific Modeling

    PubMed Central

    Chan, Harley H. L.; Siewerdsen, Jeffrey H.; Vescan, Allan; Daly, Michael J.; Prisman, Eitan; Irish, Jonathan C.

    2015-01-01

    The aim of this study was to demonstrate the role of advanced fabrication technology across a broad spectrum of head and neck surgical procedures, including applications in endoscopic sinus surgery, skull base surgery, and maxillofacial reconstruction. The initial case studies demonstrated three applications of rapid prototyping technology are in head and neck surgery: i) a mono-material paranasal sinus phantom for endoscopy training ii) a multi-material skull base simulator and iii) 3D patient-specific mandible templates. Digital processing of these phantoms is based on real patient or cadaveric 3D images such as CT or MRI data. Three endoscopic sinus surgeons examined the realism of the endoscopist training phantom. One experienced endoscopic skull base surgeon conducted advanced sinus procedures on the high-fidelity multi-material skull base simulator. Ten patients participated in a prospective clinical study examining patient-specific modeling for mandibular reconstructive surgery. Qualitative feedback to assess the realism of the endoscopy training phantom and high-fidelity multi-material phantom was acquired. Conformance comparisons using assessments from the blinded reconstructive surgeons measured the geometric performance between intra-operative and pre-operative reconstruction mandible plates. Both the endoscopy training phantom and the high-fidelity multi-material phantom received positive feedback on the realistic structure of the phantom models. Results suggested further improvement on the soft tissue structure of the phantom models is necessary. In the patient-specific mandible template study, the pre-operative plates were judged by two blinded surgeons as providing optimal conformance in 7 out of 10 cases. No statistical differences were found in plate fabrication time and conformance, with pre-operative plating providing the advantage of reducing time spent in the operation room. The applicability of common model design and fabrication techniques

  16. 3D Rapid Prototyping for Otolaryngology-Head and Neck Surgery: Applications in Image-Guidance, Surgical Simulation and Patient-Specific Modeling.

    PubMed

    Chan, Harley H L; Siewerdsen, Jeffrey H; Vescan, Allan; Daly, Michael J; Prisman, Eitan; Irish, Jonathan C

    2015-01-01

    The aim of this study was to demonstrate the role of advanced fabrication technology across a broad spectrum of head and neck surgical procedures, including applications in endoscopic sinus surgery, skull base surgery, and maxillofacial reconstruction. The initial case studies demonstrated three applications of rapid prototyping technology are in head and neck surgery: i) a mono-material paranasal sinus phantom for endoscopy training ii) a multi-material skull base simulator and iii) 3D patient-specific mandible templates. Digital processing of these phantoms is based on real patient or cadaveric 3D images such as CT or MRI data. Three endoscopic sinus surgeons examined the realism of the endoscopist training phantom. One experienced endoscopic skull base surgeon conducted advanced sinus procedures on the high-fidelity multi-material skull base simulator. Ten patients participated in a prospective clinical study examining patient-specific modeling for mandibular reconstructive surgery. Qualitative feedback to assess the realism of the endoscopy training phantom and high-fidelity multi-material phantom was acquired. Conformance comparisons using assessments from the blinded reconstructive surgeons measured the geometric performance between intra-operative and pre-operative reconstruction mandible plates. Both the endoscopy training phantom and the high-fidelity multi-material phantom received positive feedback on the realistic structure of the phantom models. Results suggested further improvement on the soft tissue structure of the phantom models is necessary. In the patient-specific mandible template study, the pre-operative plates were judged by two blinded surgeons as providing optimal conformance in 7 out of 10 cases. No statistical differences were found in plate fabrication time and conformance, with pre-operative plating providing the advantage of reducing time spent in the operation room. The applicability of common model design and fabrication techniques

  17. How accurate are rapid prototyped (RP) final orthognathic surgical wafers? A pilot study.

    PubMed

    Shqaidef, Abedalrahman; Ayoub, Ashraf F; Khambay, Balvinder S

    2014-09-01

    Computer packages have been introduced to simulate the movements of the jaw in three dimensions to facilitate planning of treatment. After final 3-dimensional virtual planning, a rapid prototype wafer can be manufactured and used in theatre. Our aim was to assess the accuracy of rapid prototyping of virtual wafers derived from laser scanned dental models using CAD/CAM software. Upper and lower plaster models from 10 orthognathic patients, the articulated models, and the conventional wafers were scanned. The virtual wafers were made from CAD/CAM software, and printed on a stereolithographic printer. We also scanned the articulated models with rapid prototype wafers in place. The validity of the final rapid prototype wafer was measured by the accuracy with which upper and lower models related to one another. The absolute mean error of the rapid prototype wafer when aligned with the dental models was 0.94 (0.09) mm. The absolute distance of the 2 models articulated by conventional and rapid prototype wafers ranged from 0.04 - 1.73mm. The rapid prototype wafers were able to orientate the upper and lower dental models with an absolute mean error of 0.94 (0.09) mm, but it ranged from 0.04-1.73mm.

  18. Comparison of laser-based rapid prototyping techniques

    NASA Astrophysics Data System (ADS)

    Humphreys, Hugh; Wimpenny, David

    2002-04-01

    A diverse range of Rapid Prototyping, or layer manufacturing techniques have evolved since the introduction of the first process in the late 1980s. Many, although not all, rapid prototyping processes rely on lasers to provide a localised and controllable source of light for curing a liquid photopolymer or heat to fuse thermoplastic powders to form objects. This paper will provide an overview of laser based rapid prototyping methods and discuss the future direction of this technology in light of the threats posed by low cost 3D printing techniques and the opportunity for the direct manufacture of metal components.

  19. Materials Selection and Their Characteristics as Used in Rapid Prototyping

    NASA Technical Reports Server (NTRS)

    Cooper, K.; Salvail, P.; Vesely, E.; Wells, D.

    1999-01-01

    NASA's Marshall Space Flight Center (MSFC) conducted a program to evaluate six technologies used in Rapid Prototyping (RP) to produce investment casting patterns. In this paper, RP refers to the collective additive fabrication technologies known as Solid Free-Form Fabrication. Such technologies are being used with increasing frequency in manufacturing applications, due in part to their rapidly expanding capabilities to fabricate models from many types of materials. This study used ABS plastic, polycarbonate, TrueForm PM6, epoxy resin, paper, starch, and wax. The baseline model was a semi-complex prototype fuel pump housing, intended for use in the X-33 reusable launch vehicle. All models were shelled in a production- grade colloidal silica ceramic. Primary coats were zircon-base flour with zircon backup, while secondary coats were silica grains with a tabular alumina backup. Each model was shelled in an identical manner, using the same atmospheric conditions and drying times, as well as the same number of layers. Bake-outs and firing cycles were consistent with the leach ability of each material. Preheat and bath temperatures were also kept consistent. All molds were cast in vacuum using a hydrogen-resistant superalloy (NASA- 23) that was developed in-house. The final technical evaluation included detailed measurements of the model and the final casting, in order to determine any dimensional changes caused by different pattern materials, as well as documentation of all defects and any obvious refractory/model reactions. Prototype production costs were estimated for each method and taken into consideration during trade-off analysis.

  20. Materials Selection and Their Characteristics as Used in Rapid Prototyping

    NASA Technical Reports Server (NTRS)

    Cooper, K.; Salvail, P.; Vesely, E.; Wells, D.

    1999-01-01

    NASA's Marshall Space Flight Center (MSFC) conducted a program to evaluate six technologies used in Rapid Prototyping (RP) to produce investment casting patterns. In this paper, RP refers to the collective additive fabrication technologies known as Solid Free-Form Fabrication. Such technologies are being used with increasing frequency in manufacturing applications, due in part to their rapidly expanding capabilities to fabricate models from many types of materials. This study used ABS plastic, polycarbonate, TrueForm PM6, epoxy resin, paper, starch, and wax. The baseline model was a semi-complex prototype fuel pump housing, intended for use in the X-33 reusable launch vehicle. All models were shelled in a production- grade colloidal silica ceramic. Primary coats were zircon-base flour with zircon backup, while secondary coats were silica grains with a tabular alumina backup. Each model was shelled in an identical manner, using the same atmospheric conditions and drying times, as well as the same number of layers. Bake-outs and firing cycles were consistent with the leach ability of each material. Preheat and bath temperatures were also kept consistent. All molds were cast in vacuum using a hydrogen-resistant superalloy (NASA- 23) that was developed in-house. The final technical evaluation included detailed measurements of the model and the final casting, in order to determine any dimensional changes caused by different pattern materials, as well as documentation of all defects and any obvious refractory/model reactions. Prototype production costs were estimated for each method and taken into consideration during trade-off analysis.

  1. Rapid prototyping of an advanced motion controller

    NASA Astrophysics Data System (ADS)

    Cooper, R. S.

    This paper illustrates how, using existing research material, an advanced motion control system was developed both rapidly and economically. The paper emphasizes the approach used to put the system together, rather than the results of the evaluation (which is still under way). The system consists of a field-oriented controlled (FOC) induction motor, along with a pulse-population modulated current motor drive. Specific areas addressed in this paper include: a thorough overview of the technologies involved in the project (with emphasis on FOC theory); use of advanced simulation tools and models to aid in system design and debug; use of existing systems wherever possible to help speed up development; and developing the system in an environment suited to true development work.

  2. Rapid prototyping as a tool for manufacturing bioartificial livers.

    PubMed

    Wang, Xiaohong; Yan, Yongnian; Zhang, Renji

    2007-11-01

    Rapid prototyping (RP) technologies are a set of manufacturing processes that can produce very complex structures directly from computer-aided design models without structure-specific tools or knowledge. These technologies might eventually enable the manufacture of human livers to create functional substitutes for treating liver failure or dysfunctionality. However, the approaches used currently face many challenges, such as the complex branched vascular and bile ductular systems and the variety of cell types, matrices and regulatory factors involved in liver development. Here, we discuss the challenges and provide evidence for the usefulness of RP in overcoming them.

  3. Web Tools for Rapid Experimental Visualization Prototyping

    DTIC Science & Technology

    2013-02-01

    in this space. We implemented these prototypes in HTML, CSS, and Javascript. The parallel coordinates view is drawn with HTML5 Canvas, and the grids...The first column in every grid is the tutorial question. We will refer to these inner grids as the technique grids. Using this method, we created...discuss observations about what can be seen in this view in the next section. 4.3 Observations Users generally took more time on the first tutorial

  4. Automated Rapid Prototyping of 3D Ceramic Parts

    NASA Technical Reports Server (NTRS)

    McMillin, Scott G.; Griffin, Eugene A.; Griffin, Curtis W.; Coles, Peter W. H.; Engle, James D.

    2005-01-01

    An automated system of manufacturing equipment produces three-dimensional (3D) ceramic parts specified by computational models of the parts. The system implements an advanced, automated version of a generic rapid-prototyping process in which the fabrication of an object having a possibly complex 3D shape includes stacking of thin sheets, the outlines of which closely approximate the horizontal cross sections of the object at their respective heights. In this process, the thin sheets are made of a ceramic precursor material, and the stack is subsequently heated to transform it into a unitary ceramic object. In addition to the computer used to generate the computational model of the part to be fabricated, the equipment used in this process includes: 1) A commercially available laminated-object-manufacturing machine that was originally designed for building woodlike 3D objects from paper and was modified to accept sheets of ceramic precursor material, and 2) A machine designed specifically to feed single sheets of ceramic precursor material to the laminated-object-manufacturing machine. Like other rapid-prototyping processes that utilize stacking of thin sheets, this process begins with generation of the computational model of the part to be fabricated, followed by computational sectioning of the part into layers of predetermined thickness that collectively define the shape of the part. Information about each layer is transmitted to rapid-prototyping equipment, where the part is built layer by layer. What distinguishes this process from other rapid-prototyping processes that utilize stacking of thin sheets are the details of the machines and the actions that they perform. In this process, flexible sheets of ceramic precursor material (called "green" ceramic sheets) suitable for lamination are produced by tape casting. The binder used in the tape casting is specially formulated to enable lamination of layers with little or no applied heat or pressure. The tape is cut

  5. Laser rapid prototyping of photonic integrated circuits

    NASA Astrophysics Data System (ADS)

    Eldada, Louay A.; Levy, Miguel; Scarmozzino, Robert; Osgood, Richard M., Jr.

    1994-07-01

    In this paper, we will describe our work at Columbia in developing a laser prototyping system, in conjunction with computer simulation, to design, fabricate, and test novel waveguide circuits. The system is also useful for manufacturing small-run circuit designs. The fundamental technique uses a laser-induced photoelectrochemical process for etching GaAs and other III-V compounds. The technique is maskless and discretionary. The computer-controlled apparatus can be programmed with any desired circuit pattern, and prototype waveguide circuits can be produced within a day. The waveguides and passive components produced with this technique include linear waveguides, tapered waveguides, abrupt and smoothly curved bends, Y-branches, asymmetric splitters, directional couplers, and optical delay lines. The passive devices are single-mode and low-loss. The technique also has the ability to vary the effective index of refraction along the device by grading the etch depth. In addition to passive devices, we have recently shown that active switching components can be prototyped by combining passive structures with laser-patterned metal electrodes. These electrodes are produced masklessly using standard metal deposition techniques coupled with laser- patterning of photoresist. In addition, metal can be deposited directly using laser-induced selective metallorgainic CVD.

  6. Characteristics of products generated by selective sintering and stereolithography rapid prototyping processes

    NASA Technical Reports Server (NTRS)

    Cariapa, Vikram

    1993-01-01

    The trend in the modern global economy towards free market policies has motivated companies to use rapid prototyping technologies to not only reduce product development cycle time but also to maintain their competitive edge. A rapid prototyping technology is one which combines computer aided design with computer controlled tracking of focussed high energy source (eg. lasers, heat) on modern ceramic powders, metallic powders, plastics or photosensitive liquid resins in order to produce prototypes or models. At present, except for the process of shape melting, most rapid prototyping processes generate products that are only dimensionally similar to those of the desired end product. There is an urgent need, therefore, to enhance the understanding of the characteristics of these processes in order to realize their potential for production. Currently, the commercial market is dominated by four rapid prototyping processes, namely selective laser sintering, stereolithography, fused deposition modelling and laminated object manufacturing. This phase of the research has focussed on the selective laser sintering and stereolithography rapid prototyping processes. A theoretical model for these processes is under development. Different rapid prototyping sites supplied test specimens (based on ASTM 638-84, Type I) that have been measured and tested to provide a data base on surface finish, dimensional variation and ultimate tensile strength. Further plans call for developing and verifying the theoretical models by carefully designed experiments. This will be a joint effort between NASA and other prototyping centers to generate a larger database, thus encouraging more widespread usage by product designers.

  7. The Development of a Programming Support System for Rapid Prototyping.

    DTIC Science & Technology

    1983-04-20

    Harvard University and will include the tools provided by the PDS plus a number of new ones specifically supporting rapid prototyping. The goals of Task 1 were to improve two tools in the PDS - the authors needed to improve

  8. Rapid prototyping in maxillofacial surgery and traumatology: case report.

    PubMed

    da Rosa, Everton Luis Santos; Oleskovicz, César Fernando; Aragão, Bruno Nogueira

    2004-01-01

    Review of the literature from 1991 to 2002 on the use of rapid prototyping in the biomedical area emphasizes the applicability of this technique to aid diagnosis and planning in Maxillofacial Surgery and Traumatology. A case report in which a TMJ ankylosis relapse was treated using rapid prototyping (selective laser sintering) for surgery planning is presented. After one year, the patient's buccal opening was 45 mm. Transitory paralysis of the facial nerve disappeared totally in six months.

  9. Rapid prototyping: A paradigm shift in investment casting

    SciTech Connect

    Atwood, C.L.; Maguire, M.C.; Baldwin, M.D.; Pardo, B.T.

    1996-09-01

    The quest for fabricating complex metal parts rapidly and with minimal cost has brought rapid prototyping (RP) processes to the forefront of the investment casting industry. Relatively recent advances in DTM Corporation`s selective laser sintering (SLS) and 3D Systems stereolithography (SL) processes have had a significant impact on the overall quality of patterns produced using these rapid prototyping processes. Sandia National Laboratories uses patterns generated from rapid prototyping processes to reduce the cycle time and cost of fabricating prototype and small lot production parts in support of a program called FASTCAST. The SLS process is used to fabricate patterns from materials such as investment casting wax, polycarbonate, and a new material called TrueForm PM{trademark}. With the timely introduction of each of these materials, the quality of patterns fabricated has improved. The development and implementation of SL QuickCast{trademark} software has enabled this process to produce highly accurate patterns for use in investment casting. This paper focuses on the successes with these new pattern materials and the infrastructure required to cast rapid prototyping patterns successfully. In addition, a brief overview of other applications of rapid prototyping at Sandia will be discussed.

  10. FROM REQUIREMENTS CAPTURE TO SILICON: A MODEL-DRIVEN SYSTEMS ENGINEERING APPROACH TO RAPID DESIGN, PROTOTYPING AND DEVELOPMENT USED IN THE OAK RIDGE NATIONAL LABORATORY'S COGNITIVE RADIO PROGRAM

    SciTech Connect

    Buckner, Mark A; Kaldenbach, Brian J; Nory, Nakhaee; Moore, Michael Roy; Bouldin, Donald; Mills, Jonathan

    2008-01-01

    The performance and complexity of the signal processing hardware accessible to SDR/CR/RADAR designers has quickly out-paced the available design tools. The advances in Digital Signal Processors (DSP) both fixed- and floating-point, Field Programmable Gate Arrays (FPGA), and multicore processors have enabled rapid prototyping and deployment of platforms that can be dynamically reconfigured in the field to implement a variety of SDR/CR/RADAR waveforms. Until recently the process of creating waveforms meant starting with high-level mathematical models and simulations and then creating production quality code that can operate on this variety of specialized hardware using either hand coding or vendor specific tools, which are typically limited to single processor solutions. This paper discusses an integrated model-driven design process and tool-flow used in ORNL's Cognitive Radio Program. It describes how the process and tool-flow are used on a variety of SDR and CR projects and in the development of a software-defined RADAR environment simulator. It describes how, from a single Simulink model, a single deadlock free real-time multiprocessor application is created and executed on a network of heterogeneous processors. We also describe recent progress on extending the process/tool-flow to design digital ASICs and our plans for future extensions. We close by highlighting the benefits being realized from applying this design flow to SDR/CR/RADAR projects at ORNL: (1) a significant reduction in the time required to develop, prototype, implement and test SDR/CR/RADAR waveforms, (2) increased reusability/retargetabilty of SDR/CR/RADAR designs and signal processing library components, (3) the ability to quickly port SDR/CR/RADAR waveforms to different hardware systems and processor types, (4) improvements in documentation, and (5) traceability of system components back to original requirements.

  11. Accuracy and precision of polyurethane dental arch models fabricated using a three-dimensional subtractive rapid prototyping method with an intraoral scanning technique

    PubMed Central

    Kim, Jae-Hong; Kim, Ki-Baek; Kim, Woong-Chul; Kim, Ji-Hwan

    2014-01-01

    Objective This study aimed to evaluate the accuracy and precision of polyurethane (PUT) dental arch models fabricated using a three-dimensional (3D) subtractive rapid prototyping (RP) method with an intraoral scanning technique by comparing linear measurements obtained from PUT models and conventional plaster models. Methods Ten plaster models were duplicated using a selected standard master model and conventional impression, and 10 PUT models were duplicated using the 3D subtractive RP technique with an oral scanner. Six linear measurements were evaluated in terms of x, y, and z-axes using a non-contact white light scanner. Accuracy was assessed using mean differences between two measurements, and precision was examined using four quantitative methods and the Bland-Altman graphical method. Repeatability was evaluated in terms of intra-examiner variability, and reproducibility was assessed in terms of inter-examiner and inter-method variability. Results The mean difference between plaster models and PUT models ranged from 0.07 mm to 0.33 mm. Relative measurement errors ranged from 2.2% to 7.6% and intraclass correlation coefficients ranged from 0.93 to 0.96, when comparing plaster models and PUT models. The Bland-Altman plot showed good agreement. Conclusions The accuracy and precision of PUT dental models for evaluating the performance of oral scanner and subtractive RP technology was acceptable. Because of the recent improvements in block material and computerized numeric control milling machines, the subtractive RP method may be a good choice for dental arch models. PMID:24696823

  12. Novel application of rapid prototyping for simulation of bronchoscopic anatomy.

    PubMed

    Bustamante, Sergio; Bose, Somnath; Bishop, Paul; Klatte, Ryan; Norris, Frederick

    2014-08-01

    The authors used rapid prototyping (RP) technology to create anatomically congruent models of tracheo-bronchial tree for teaching relevant bronchoscopic anatomy. Pilot study. A single level tertiary academic medical center. Two 3 dimensional (3D) models of tracheo-bronchial tree (one showing normal anatomy and another with an early take off of right apical bronchus) were recreated from Computed Tomographic images using RP technology. These images were then attached to mannequins and examined with a flexible fiberoptic bronchoscope (FFB). These images were then compared with the actual FFB images obtained during lung isolation. The images obtained through the 3D models were found to be congruent to actual patient anatomy. RP can be successfully used to create anatomically accurate models from imaging studies. There is potential for RP to become a valuable educational tool in the future. © 2013 Elsevier Inc. All rights reserved.

  13. Rapid Prototyping of Application Specific Processors.

    DTIC Science & Technology

    1987-12-01

    DataRequest 0 DataReq 1 DataValid 0 DataVal 1I~. NatDefined 0 % .\\, Al 157 % % APPENDIX E ASP Prototype Microcode .. begin: flop; the first section of...executed at this point DataReq; DataLdPads; load test data from datapads DataVal ;, RO RO RI DataDrA mov; put data in RI Ri 10 110 DataLdC mov; test...ability to put back into datareg DataVal ; output value Ri RO Ri incr; test ALU incr function and busses R1 RO 110 DataLdC mov; Ri RO Ri incr Data%’al; RI

  14. Three-dimensional model of the skull and the cranial bones reconstructed from CT scans designed for rapid prototyping process.

    PubMed

    Skrzat, Janusz; Spulber, Alexandru; Walocha, Jerzy

    This paper presents the effects of building mesh models of the human skull and the cranial bones from a series of CT-scans. With the aid of computer so ware, 3D reconstructions of the whole skull and segmented cranial bones were performed and visualized by surface rendering techniques. The article briefly discusses clinical and educational applications of 3D cranial models created using stereolitographic reproduction.

  15. Free-form surface reconstruction for machine vision rapid prototyping

    NASA Astrophysics Data System (ADS)

    Bradley, Colin; Vickers, Geoffrey W.

    1993-09-01

    Prototyping is an essential step in the manufacture of many objects, both consumer and industrial. A fundamental step in this process is the definition of the 3-D form of the object shape, for example, a designer's models created in clay or wood. A 3-D vision system (range sensor) offers the advantage of speed in defining shapes compared to a traditional tactile sensor. The viability of using range sensors is demonstrated by the development of a rapid prototyping system comprised of a laser-based range sensor and software that creates a computer model of the object. One particularly important area of application is the reverse engineering of models comprised of free-form surfaces. This is important in mold and die manufacture for aerodynamic and ergonomic object surfaces. Several methods of modeling free-form surfaces from irregular data are examined and a radial basis function approach is used in developing a self-contained, interactive software package utilizing the laser-generated range data.

  16. Rapid prototyping of glass microfluidic chips

    NASA Astrophysics Data System (ADS)

    Kotz, Frederik; Plewa, Klaus; Bauer, Werner; Hanemann, Thomas; Waldbaur, Ansgar; Wilhelm, Elisabeth; Neumann, Christiane; Rapp, Bastian E.

    2015-03-01

    In academia the rapid and flexible creation of microfluidic chips is of great importance for microfluidic research. Besides polymers glass is a very important material especially when high chemical and temperature resistance are required. However, glass structuring is a very hazardous process which is not accessible to most members of the microfluidic community. We therefore sought a new method for the rapid and simple creation of transparent microfluidic glass chips by structuring and sintering amorphous silica suspensions. The whole process from a digital mask layout to a microstructured glass sheet can be done within two days. In this paper we show the applicability of this process to fabricate capillary driven microfluidic systems.

  17. Virtual Combat Convoy Trainer: Successful Rapid Prototyping

    DTIC Science & Technology

    2004-12-01

    32825 ABSTRACT The Lockheed Martin (LM) and Fire Arms Training Systems (FATS) Virtual Combat Convoy Trainer ( VCCT ) was developed as a rapid...based systems with complimentary capabilities which allowed the system to go from concept to deployment in under 21 days. The LM-FATS VCCT ...solution (aka VCCT -L) provides basic to advanced convoy skills training and mission rehearsal, incorporating precision weapons engagement training

  18. Minimizing the extra-oral time in autogeneous tooth transplantation: use of computer-aided rapid prototyping (CARP) as a duplicate model tooth

    PubMed Central

    Lee, Seung-Jong

    2012-01-01

    Objectives The maintenance of the healthy periodontal ligament cells of the root surface of donor tooth and intimate surface contact between the donor tooth and the recipient bone are the key factors for successful tooth transplantation. In order to achieve these purposes, a duplicated donor tooth model can be utilized to reduce the extra-oral time using the computer-aided rapid prototyping (CARP) technique. Materials and Methods Briefly, a three-dimensional digital imaging and communication in medicine (DICOM) image with the real dimensions of the donor tooth was obtained from a computed tomography (CT), and a life-sized resin tooth model was fabricated. Dimensional errors between real tooth, 3D CT image model and CARP model were calculated. And extra-oral time was recorded during the autotransplantation of the teeth. Results The average extra-oral time was 7 min 25 sec with the range of immediate to 25 min in cases which extra-oral root canal treatments were not performed while it was 9 min 15 sec when extra-oral root canal treatments were performed. The average radiographic distance between the root surface and the alveolar bone was 1.17 mm and 1.35 mm at mesial cervix and apex; they were 0.98 mm and 1.26 mm at the distal cervix and apex. When the dimensional errors between real tooth, 3D CT image model and CARP model were measured in cadavers, the average of absolute error was 0.291 mm between real teeth and CARP model. Conclusions These data indicate that CARP may be of value in minimizing the extra-oral time and the gap between the donor tooth and the recipient alveolar bone in tooth transplantation. PMID:23431083

  19. TOPAZ II Anti-Criticality Device Rapid Prototype

    NASA Astrophysics Data System (ADS)

    Campbell, Donald R.; Otting, William D.

    1994-07-01

    The Ballistic Missile Defense Organization (BMDO) has been working on a Nuclear Electric Propulsion Space Test Project (NEPSTP) using an existing Russian Topaz II reactor system to power the NEPSTP satellite. Safety investigations have shown that it will be possible to safely launch the Topaz II system in the United States with some modification to preclude water flooded criticality. A ``fuel-out'' water subcriticality concept was selected by the Los Alamos National Laboratory (LANL) as the baseline concept. A fuel-out anti-criticality device (ACD) conceptual design was developed by Rockwell. The concept functions to hold the fuel from the four centermost thermionic fuel elements (TFEs) outside the reactor during launch and reliably inserts the fuel into the reactor once the operational orbit is achieved. A four-tenths scale ACD rapid prototype model, fabricated from the CATIA solids design model, clearly shows in three dimensions the relative size and spatial relationship of the ACD components.

  20. Inspection, 3D modelling, and rapid prototyping of cultural heritage by means of a 3D optical digitiser

    NASA Astrophysics Data System (ADS)

    Docchio, F.; Sansoni, G.; Trebeschi, M.

    2005-06-01

    This paper presents the activity carried out to perform the three-dimensional acquisition of the "Vittoria Alata", a 2m-high, bronze statue, symbol of our City, located at the Civici Musei di Arte e Storia (S. Giulia) of Brescia. The acquisition of the statue has been performed by using a three-dimensional vision system based on active triangulation and on the projection of non-coherent light. This system, called OPL-3D, represents one of the research products of our Laboratory, which has been active for years in the development of techniques and systems for the contactless acquisition of free-form, complex shapes. The study, originally motivated by the need to explore a new hypothesis on the origin of the "Vittoria Alata", led to its complete digitization and description in terms of both polygonal and NURBS-based models. A suite of copies of the whole statue has been obtained in the framework of the collaboration between the City Museum and the EOS Electro Optical Systems GmbH, located in Munich, Germany. As a first step, one 30 cm-high replica of the whole statue has been produced using a low-resolution triangle model of the statue (3.5 millions of triangles). As a second step, two 1:1 scale copies of the statue have been produced. For them, the Laboratory has provided the high resolution STL file (16 millions of triangles). The paper discusses in detail the hardware and the software facilities used to implement the whole process, and gives a comprehensive description of the results.

  1. Thermal Modeling and Simulation of Electron Beam Melting for Rapid Prototyping on Ti6Al4V Alloys

    NASA Astrophysics Data System (ADS)

    Neira Arce, Alderson

    To be a viable solution for contemporary engineering challenges, the use of titanium alloys in a wider range of applications requires the development of new techniques and processes that are able to decrease production cost and delivery times. As a result, the use of material consolidation in a near-net-shape fashion, using dynamic techniques like additive manufacturing by electron beam selective melting EBSM represents a promising method for part manufacturing. However, a new product material development can be cost prohibitive, requiring the use of computer modeling and simulation as a way to decrease turnaround time. To ensure a proper representation of the EBSM process, a thermophysical material characterization and comparison was first performed on two Ti6Al4V powder feedstock materials prepared by plasma (PREP) and gas atomized (GA) processes. This evaluation comprises an evaluation on particle size distribution, density and powder surface area, collectively with the temperature dependence on properties such as heat capacity, thermal diffusivity, thermal conductivity and surface emissivity. Multiple techniques were employed in this evaluation, including high temperature differential scanning calorimetry (HT-DSC), laser flash analysis (LFA), infrared remote temperature analysis (IR-Thermography), laser diffraction, liquid and gas pycnometry using mercury and krypton adsorption respectively. This study was followed by the review of complementary strategies to simulate the temperature evolution during the EBSM process, using a finite element analysis package called COMSOL Multiphysics. Two alternatives dedicated to representing a moving heat source (electron beam) and the powder bed were developed using a step-by-step approximation initiative. The first method consisted of the depiction of a powder bed discretized on an array of domains, each one representing a static melt pool, where the moving heat source was illustrated by a series of time dependant selective

  2. Rapid prototyping in the development of image processing systems

    NASA Astrophysics Data System (ADS)

    von der Fecht, Arno; Kelm, Claus Thomas

    2004-08-01

    This contribution presents a rapid prototyping approach for the real-time demonstration of image processing algorithms. As an example EADS/LFK has developed a basic IR target tracking system implementing this approach. Traditionally in research and industry time-independent simulation of image processing algorithms on a host computer is processed. This method is good for demonstrating the algorithms' capabilities. Rarely done is a time-dependent simulation or even a real-time demonstration on a target platform to prove the real-time capabilities. In 1D signal processing applications time-dependent simulation and real-time demonstration has already been used for quite a while. For time-dependent simulation Simulink from The MathWorks has established as an industry standard. Combined with The MathWorks' Real-Time Workshop the simulation model can be transferred to a real-time target processor. The executable is generated automatically by the Real-Time Workshop directly out of the simulation model. In 2D signal processing applications like image processing The Mathworks' Matlab is commonly used for time-independent simulation. To achieve time-dependent simulation and real-time demonstration capabilities the algorithms can be transferred to Simulink, which in fact runs on top of Matlab. Additionally to increase the performance Simulink models or parts of them can be transferred to Xilinx FPGAs using Xilinx' System Generator. With a single model and the automatic workflow both, a time-dependant simulation and the real-time demonstration, are covered leading to an easy and flexible rapid prototyping approach. EADS/LFK is going to use this approach for a wider spectrum of IR image processing applications like automatic target recognition or image based navigation or imaging laser radar target recognition.

  3. Validation of transgenic mice harboring the human prototype c-Ha-ras gene as a bioassay model for rapid carcinogenicity testing.

    PubMed

    Yamamoto, S; Urano, K; Nomura, T

    1998-12-28

    Studies were conducted to validate the transgenic (Tg) mice harboring human prototype c-Ha-ras gene, namely the rasH2 mice (CB6F1), as a model for rapid carcinogenicity testing. Short-term (26 weeks) carcinogenicity testing of 18 mutagenic (Salmonella) trans-species carcinogens, two mutagenic single-species (mouse-only) carcinogens, six non-mutagenic trans-species carcinogens, one non-mutagenic single-species (mouse-only) carcinogen, four mutagenic non-carcinogens and four non-mutagenic non-carcinogens were completed. The studies revealed that the Tg mice are able to detect various types of mutagenic carcinogens and may also detect various non-mutagenic carcinogens within 26 weeks. Dose-dependent tumor responses were observed with various carcinogens except for a few equivocal cases. The validation studies also revealed that the Tg mice are generally much more susceptible to both mutagenic and non-mutagenic carcinogens than control non-Tg mice. Most of the malignant tumors were observed in the carcinogen-treated Tg mice and only very few or none in the corresponding non-Tg mice. Most of the carcinogens tested induced some of the target organ tumors observed in B6C3F1 mice in a 2-year bioassay as well as certain types of tumors specific to the Tg mice, i.e. lung alveolar epithelial tumors, spleen hemangiosarcomas, forestomach squamous cell tumors. No significant tumor induction has been observed in the Tg mice either with mutagenic or non-mutagenic non-carcinogens. Although further validation studies are still required, the rasH2 mouse seems to be a promising candidate as an animal model for the development of a rapid carcinogenicity testing system.

  4. Rapid Prototyping and the Human Factors Engineering Process

    DTIC Science & Technology

    2016-08-29

    qr-..2. 9 Rapid prototyping or ’virtual prototyping’ of human- machine interfaces offers the possibility of putting the human operator ’in the loop...facilitates an iterative approach to the development of the human- machine interface, and that is most applicable to the early stages of systems...factors engineering (HFE) process re- commended for the development of human- machine systems is based on a series of increasin¥ly detailed analyses of

  5. Microgravity Manufacturing: Extending Rapid Prototyping Past the Horizon

    NASA Technical Reports Server (NTRS)

    Cooper, Ken

    2003-01-01

    Over the last decade, rapid prototyping (RP) technologies have continued to advance in all aspects of operation and application. From continuously advanced materials and processes development to more hard-core manufacturing uses, the RP realm has stretched considerably past its original expectations as a prototyping capability. This paper discusses the unique applications for which NASA has chosen these manufacturing techniques to be utilized in outer space.

  6. Rapid laser prototyping of plasmonic components

    NASA Astrophysics Data System (ADS)

    Reinhardt, C.; Kiyan, R.; Passinger, S.; Stepanov, A. L.; Ostendorf, A.; Chichkov, B. N.

    2007-11-01

    Renewed and growing interest in the field of surface plasmon polaritons (SPPs) comes from a rapid advance of nanostructuring technologies. In this paper, we will report on the application of two-photon polymerization (2PP) technique for the fabrication of dielectric SPP-structures, which can be used for localization, guiding, and manipulation of SPPs on a subwavelength scale. This technology is based on nonlinear absorption of near-infrared femtosecond laser pulses. Resolutions down to 100 nm (and even better) are already achievable. Characterization of these structures is performed by leakage radiation microscopy. 2PP allows the fabrication of dielectric waveguides, splitters, and couplers directly on metal surfaces. The dielectric structures on metal films are demonstrated to be very efficient for the excitation of SPPs. Using these structures, one can achieve excitation and focusing of the resulting plasmon field.

  7. Surgical planning and microvascular reconstruction of the mandible with a fibular flap using computer-aided design, rapid prototype modelling, and precontoured titanium reconstruction plates: a prospective study.

    PubMed

    Sieira Gil, R; Roig, A Marí; Obispo, C Arranz; Morla, A; Pagès, C Martí; Perez, J Llopis

    2015-01-01

    The standard of mandibular reconstruction has increased since the introduction of computer-assisted design (CAD) and rapid prototype modelling (RPM) for surgical planning. Between 2008 and 2013, a prospective pilot study of 20 patients was planned to compare the outcomes of patients treated by mandibular reconstruction who had CAD and RPM-guided operations using a precontoured titanium plate, with the outcomes of patients treated conventionally. We recorded the time taken for reconstruction, total operating time, and whether this type of planning could improve the results of mandibular reconstruction. We found significant differences in the incidence of dental malocclusion (p=0.03) and exposure of the titanium plate (p=0.009). The mean operating time for reconstruction in the preoperative planning group was 135 (37)min compared with 176 (58)min in the conventional group (p=0.04). Preoperative planning using CAD and RPM can increase the accuracy of microvascular mandibular reconstruction and reduce the operating time for reconstruction. Copyright © 2014 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  8. Methods and systems for rapid prototyping of high density circuits

    SciTech Connect

    Palmer, Jeremy A.; Davis, Donald W.; Chavez, Bart D.; Gallegos, Phillip L.; Wicker, Ryan B.; Medina, Francisco R.

    2008-09-02

    A preferred embodiment provides, for example, a system and method of integrating fluid media dispensing technology such as direct-write (DW) technologies with rapid prototyping (RP) technologies such as stereolithography (SL) to provide increased micro-fabrication and micro-stereolithography. A preferred embodiment of the present invention also provides, for example, a system and method for Rapid Prototyping High Density Circuit (RPHDC) manufacturing of solderless connectors and pilot devices with terminal geometries that are compatible with DW mechanisms and reduce contact resistance where the electrical system is encapsulated within structural members and manual electrical connections are eliminated in favor of automated DW traces. A preferred embodiment further provides, for example, a method of rapid prototyping comprising: fabricating a part layer using stereolithography and depositing thermally curable media onto the part layer using a fluid dispensing apparatus.

  9. Can rapid prototyping ever become a routine feature in general dental practice?

    PubMed

    Harris, Jonathan; Rimell, James

    2002-12-01

    Rapid prototyping is a technique for the production of solid objects from computer models. The variety of rapid prototyping devices and materials that can be processed is increasing all the time. In this paper, the authors examine the potential for the application of current devices to general dental practice and speculate on developments that could make this technique an attractive prospect within the dental surgery.

  10. Additive Manufacturing: From Rapid Prototyping to Flight

    NASA Technical Reports Server (NTRS)

    Prater, Tracie

    2015-01-01

    Additive manufacturing (AM) offers tremendous promise for the rocket propulsion community. Foundational work must be performed to ensure the safe performance of AM parts. Government, industry, and academia must collaborate in the characterization, design, modeling, and process control to accelerate the certification of AM parts for human-rated flight.

  11. Rapid Prototyping: State of the Art Review

    DTIC Science & Technology

    2003-10-23

    Stereolithography or other Photopolymer Based • Laser Sintering or Net Shaping • Fused Deposition • Inkjet and 3D Printing • Lamination...relatively new class of technology that includes processes such as stereolithography, fused deposition modeling, laser sintering, and 3D inkjet ...Laser g Source: Navy Surface Warfare Center, Newport Figure 4. Selective Laser Sintering Process. 5 A final example, inkjet printing, is

  12. Joint Program on Rapid Prototyping. RaPIER (Rapid Prototyping to Investigate End-User Requirements).

    DTIC Science & Technology

    1985-03-28

    Prototype System Description Language," ISSI Technical Report, unnumbered, January 30,198 6 ., . [JONES84] T. Capers Jones. "Reusability in Programming: A...Systems, Inc.. "PSDL: Prototype System * Description Language," ISSI Technical Report, unnumbered, January 30, 1986. T. Capers Jones. "Reusability in...Game Design," IEEE Software, Vol. 1, No. 4, October 1984, pp. 28-38. -[LISKOV5] -5. Barbara H. Liskov, Stephen N. Zilles. "Specification Techniques for j

  13. Rapid algorithm prototyping and implementation for power quality measurement

    NASA Astrophysics Data System (ADS)

    Kołek, Krzysztof; Piątek, Krzysztof

    2015-12-01

    This article presents a Model-Based Design (MBD) approach to rapidly implement power quality (PQ) metering algorithms. Power supply quality is a very important aspect of modern power systems and will become even more important in future smart grids. In this case, maintaining the PQ parameters at the desired level will require efficient implementation methods of the metering algorithms. Currently, the development of new, advanced PQ metering algorithms requires new hardware with adequate computational capability and time intensive, cost-ineffective manual implementations. An alternative, considered here, is an MBD approach. The MBD approach focuses on the modelling and validation of the model by simulation, which is well-supported by a Computer-Aided Engineering (CAE) packages. This paper presents two algorithms utilized in modern PQ meters: a phase-locked loop based on an Enhanced Phase Locked Loop (EPLL), and the flicker measurement according to the IEC 61000-4-15 standard. The algorithms were chosen because of their complexity and non-trivial development. They were first modelled in the MATLAB/Simulink package, then tested and validated in a simulation environment. The models, in the form of Simulink diagrams, were next used to automatically generate C code. The code was compiled and executed in real-time on the Zynq Xilinx platform that combines a reconfigurable Field Programmable Gate Array (FPGA) with a dual-core processor. The MBD development of PQ algorithms, automatic code generation, and compilation form a rapid algorithm prototyping and implementation path for PQ measurements. The main advantage of this approach is the ability to focus on the design, validation, and testing stages while skipping over implementation issues. The code generation process renders production-ready code that can be easily used on the target hardware. This is especially important when standards for PQ measurement are in constant development, and the PQ issues in emerging smart

  14. Patient specific ankle-foot orthoses using rapid prototyping

    PubMed Central

    2011-01-01

    Background Prefabricated orthotic devices are currently designed to fit a range of patients and therefore they do not provide individualized comfort and function. Custom-fit orthoses are superior to prefabricated orthotic devices from both of the above-mentioned standpoints. However, creating a custom-fit orthosis is a laborious and time-intensive manual process performed by skilled orthotists. Besides, adjustments made to both prefabricated and custom-fit orthoses are carried out in a qualitative manner. So both comfort and function can potentially suffer considerably. A computerized technique for fabricating patient-specific orthotic devices has the potential to provide excellent comfort and allow for changes in the standard design to meet the specific needs of each patient. Methods In this paper, 3D laser scanning is combined with rapid prototyping to create patient-specific orthoses. A novel process was engineered to utilize patient-specific surface data of the patient anatomy as a digital input, manipulate the surface data to an optimal form using Computer Aided Design (CAD) software, and then download the digital output from the CAD software to a rapid prototyping machine for fabrication. Results Two AFOs were rapidly prototyped to demonstrate the proposed process. Gait analysis data of a subject wearing the AFOs indicated that the rapid prototyped AFOs performed comparably to the prefabricated polypropylene design. Conclusions The rapidly prototyped orthoses fabricated in this study provided good fit of the subject's anatomy compared to a prefabricated AFO while delivering comparable function (i.e. mechanical effect on the biomechanics of gait). The rapid fabrication capability is of interest because it has potential for decreasing fabrication time and cost especially when a replacement of the orthosis is required. PMID:21226898

  15. Patient specific ankle-foot orthoses using rapid prototyping.

    PubMed

    Mavroidis, Constantinos; Ranky, Richard G; Sivak, Mark L; Patritti, Benjamin L; DiPisa, Joseph; Caddle, Alyssa; Gilhooly, Kara; Govoni, Lauren; Sivak, Seth; Lancia, Michael; Drillio, Robert; Bonato, Paolo

    2011-01-12

    Prefabricated orthotic devices are currently designed to fit a range of patients and therefore they do not provide individualized comfort and function. Custom-fit orthoses are superior to prefabricated orthotic devices from both of the above-mentioned standpoints. However, creating a custom-fit orthosis is a laborious and time-intensive manual process performed by skilled orthotists. Besides, adjustments made to both prefabricated and custom-fit orthoses are carried out in a qualitative manner. So both comfort and function can potentially suffer considerably. A computerized technique for fabricating patient-specific orthotic devices has the potential to provide excellent comfort and allow for changes in the standard design to meet the specific needs of each patient. In this paper, 3D laser scanning is combined with rapid prototyping to create patient-specific orthoses. A novel process was engineered to utilize patient-specific surface data of the patient anatomy as a digital input, manipulate the surface data to an optimal form using Computer Aided Design (CAD) software, and then download the digital output from the CAD software to a rapid prototyping machine for fabrication. Two AFOs were rapidly prototyped to demonstrate the proposed process. Gait analysis data of a subject wearing the AFOs indicated that the rapid prototyped AFOs performed comparably to the prefabricated polypropylene design. The rapidly prototyped orthoses fabricated in this study provided good fit of the subject's anatomy compared to a prefabricated AFO while delivering comparable function (i.e. mechanical effect on the biomechanics of gait). The rapid fabrication capability is of interest because it has potential for decreasing fabrication time and cost especially when a replacement of the orthosis is required.

  16. Can MODIS Data Calibrate and Validate Coastal Sediment Transport Models? Rapid Prototyping Using 250 m Data and the ECOMSED Model for Lake Pontchartrain, LA USA

    NASA Technical Reports Server (NTRS)

    Miller, Richard L.; Georgiou, Ioannis; Glorioso, Mark V.; McCorquodale, J. Alex; Crowder, Keely

    2006-01-01

    Field measurements from small boats and sparse arrays of instrumented buoys often do not provide sufficient data to capture the dynamic nature of biogeophysical parameters in may coastal aquatic environments. Several investigators have shown the MODIS 250 m images can provide daily synoptic views of suspended sediment concentration in coastal waters to determine sediment transport and fate. However, the use of MODIS for coastal environments can be limited due to a lack of cloud-free images. Sediment transport models are not constrained by sky conditions but often suffer from a lack of in situ observations for model calibration or validation. We demonstrate here the utility of MODIS 250 m to calibrate (set model parameters), validate output, and set or reset initial conditions of a hydrodynamic and sediment transport model (ECOMSED) developed for Lake Pontchartrain, LA USA. We present our approach in the context of how to quickly assess of 'prototype' an application of NASA data to support environmental managers and decision makers. The combination of daily MODIS imagery and model simulations offer a more robust monitoring and prediction system of suspended sediments than available from either system alone.

  17. Rapid Prototyping Methodology in Action: A Developmental Study.

    ERIC Educational Resources Information Center

    Jones, Toni Stokes; Richey, Rita C.

    2000-01-01

    Investigated the use of rapid prototyping methodologies in two projects conducted in a natural work setting to determine the nature of its use by designers and customers and the extent to which its use enhances traditional instructional design. Discusses design and development cycle-time reduction, product quality, and customer and designer…

  18. Increasing the Efficacy of Informal Video through Rapid Prototyping.

    ERIC Educational Resources Information Center

    Appelman, Robert L.; And Others

    Educators participating in distance education have generally not received training in the production of effective video, although they do need to be able to appear in video suitable for effective instruction. The level of video quality required is referred to as "informal" video. Rapid prototyping is a concept in which formative…

  19. Rapid Prototyping of NASA's Solar and Meteorological Data For Regional Level Modeling of Agricultural and Bio-fuel Crop Phenology and Yield Potential

    NASA Astrophysics Data System (ADS)

    Hoell, J. M.; Stackhouse, P. W.; Eckman, R. S.

    2006-12-01

    fluxes (4 to 7 day lag) produced via the NASA FLASHFlux (Fast Longwave and SHortwave radiative Fluxes) project. We will also discuss a Rapid Prototype Project designed to demonstrate the viability of using the resulting 1-degree resolution regional-to-global meteorological and solar radiation data products as inputs to agricultural based Decision Support Systems for improved production of food, feedstock and bio- fuel crops. The data requirements of these DSS's are discussed including the requirements for timeliness and spatial resolution. These have ramifications for future remote sensing, data analysis and modeling systems to support agricultural applications.

  20. Rapid prototyping polymers for microfluidic devices and high pressure injections.

    PubMed

    Sollier, Elodie; Murray, Coleman; Maoddi, Pietro; Di Carlo, Dino

    2011-11-21

    Multiple methods of fabrication exist for microfluidic devices, with different advantages depending on the end goal of industrial mass production or rapid prototyping for the research laboratory. Polydimethylsiloxane (PDMS) has been the mainstay for rapid prototyping in the academic microfluidics community, because of its low cost, robustness and straightforward fabrication, which are particularly advantageous in the exploratory stages of research. However, despite its many advantages and its broad use in academic laboratories, its low elastic modulus becomes a significant issue for high pressure operation as it leads to a large alteration of channel geometry. Among other consequences, such deformation makes it difficult to accurately predict the flow rates in complex microfluidic networks, change flow speed quickly for applications in stop-flow lithography, or to have predictable inertial focusing positions for cytometry applications where an accurate alignment of the optical system is critical. Recently, other polymers have been identified as complementary to PDMS, with similar fabrication procedures being characteristic of rapid prototyping but with higher rigidity and better resistance to solvents; Thermoset Polyester (TPE), Polyurethane Methacrylate (PUMA) and Norland Adhesive 81 (NOA81). In this review, we assess these different polymer alternatives to PDMS for rapid prototyping, especially in view of high pressure injections with the specific example of inertial flow conditions. These materials are compared to PDMS, for which magnitudes of deformation and dynamic characteristics are also characterized. We provide a complete and systematic analysis of these materials with side-by-side experiments conducted in our lab that also evaluate other properties, such as biocompatibility, solvent compatibility, and ease of fabrication. We emphasize that these polymer alternatives, TPE, PUMA and NOA, have some considerable strengths for rapid prototyping when bond

  1. Comparison of orbital volume obtained by tomography and rapid prototyping.

    PubMed

    Roça, Guilherme Berto; Foggiatto, José Aguiomar; Ono, Maria Cecilia Closs; Ono, Sergio Eiji; da Silva Freitas, Renato

    2013-11-01

    This study aims to compare orbital volume obtained by helical tomography and rapid prototyping. The study sample was composed of 6 helical tomography scans. Eleven healthy orbits were identified to have their volumes measured. The volumetric analysis with the helical tomography utilized the same protocol developed by the Plastic Surgery Unit of the Federal University of Paraná. From the CT images, 11 prototypes were created, and their respective volumes were analyzed in 2 ways: using software by SolidWorks and by direct analysis, when the prototype was filled with saline solution. For statistical analysis, the results of the volumes of the 11 orbits were considered independent. The average orbital volume measurements obtained by the method of Ono et al was 20.51 cm, the average obtained by the SolidWorks program was 20.64 cm, and the average measured using the prototype method was 21.81 cm. The 3 methods demonstrated a strong correlation between the measurements. The right and left orbits of each patient had similar volumes. The tomographic method for the analysis of orbital volume using the Ono protocol yielded consistent values, and by combining this method with rapid prototyping, both reliability validations of results were enhanced.

  2. The Requirements and Design of the Rapid Prototyping Capabilities System

    NASA Astrophysics Data System (ADS)

    Haupt, T. A.; Moorhead, R.; O'Hara, C.; Anantharaj, V.

    2006-12-01

    The Rapid Prototyping Capabilities (RPC) system will provide the capability to rapidly evaluate innovative methods of linking science observations. To this end, the RPC will provide the capability to integrate the software components and tools needed to evaluate the use of a wide variety of current and future NASA sensors, numerical models, and research results, model outputs, and knowledge, collectively referred to as "resources". It is assumed that the resources are geographically distributed, and thus RPC will provide the support for the location transparency of the resources. The RPC system requires providing support for: (1) discovery, semantic understanding, secure access and transport mechanisms for data products available from the known data provides; (2) data assimilation and geo- processing tools for all data transformations needed to match given data products to the model input requirements; (3) model management including catalogs of models and model metadata, and mechanisms for creation environments for model execution; and (4) tools for model output analysis and model benchmarking. The challenge involves developing a cyberinfrastructure for a coordinated aggregate of software, hardware and other technologies, necessary to facilitate RPC experiments, as well as human expertise to provide an integrated, "end-to-end" platform to support the RPC objectives. Such aggregation is to be achieved through a horizontal integration of loosely coupled services. The cyberinfrastructure comprises several software layers. At the bottom, the Grid fabric encompasses network protocols, optical networks, computational resources, storage devices, and sensors. At the top, applications use workload managers to coordinate their access to physical resources. Applications are not tightly bounded to a single physical resource. Instead, they bind dynamically to resources (i.e., they are provisioned) via a common grid infrastructure layer. For the RPC system, the

  3. Laser-Controlled Rapid Prototyping of Photonic Integrated Circuits.

    NASA Astrophysics Data System (ADS)

    Eldada, Louay A.

    1994-01-01

    Photonic integrated circuits offer important cost and environmental advantages over circuits composed of discrete components. However, the design and fabrication of complex, large-area photonic integrated circuits (PICs) is severely limited by the lack of prototyping tools as well as the appropriate device structures. This thesis describes the use of a novel laser fabrication process for the rapid prototyping of integrated optical circuits in compound semiconductor substrates. The fabrication is based on a type of laser direct photoelectrochemical etching process that uses a focused laser beam which is scanned under computer control to form micrometer-scale grooves, thereby patterning rib-like optical waveguide structures. The computer-controlled apparatus can be programmed with any desired circuit pattern, and prototype waveguide circuits can be produced within a day. The technique does not require the use of a mask; thus, the etching can be done in a single step. In the first part of this thesis, the technique of micrometer-scale photoelectrochemical etching of GaAs is described. The use of this technique for the fabrication of several passive integrated optical devices in GaAs is then presented. These "building block" devices include linear waveguides, bends, Y-branches, and tapers. From these, we were able to form simple passive devices such as splitters and directional couplers. These devices have low optical loss, are single-mode, and can be accurately modeled using effective index calculations. The usefulness of this technique as a prototyping tool is then demonstrated by its use in the fabrication of the first sub-Angstrom integrated channel-dropping filter. After the presentation of the passive devices results, the use of this technique to fabricate several active devices is discussed. These electrooptic devices include a polarization modulator, an integrated amplitude modulator consisting of a polarization modulator and an on-chip polarizer, and an

  4. Digital image capture and rapid prototyping of the maxillofacial defect.

    PubMed

    Sabol, Jennifer V; Grant, Gerald T; Liacouras, Peter; Rouse, Stephen

    2011-06-01

    In order to restore an extraoral maxillofacial defect, a moulage impression is commonly made with traditional impression materials. This technique has some disadvantages, including distortion of the site due to the weight of the impression material, changes in tissue location with modifications of the patient position, and the length of time and discomfort for the patient due to the impression procedure and materials used. The use of the commercially available 3dMDface™ System creates 3D images of soft tissues to form an anatomically accurate 3D surface image. Rapid prototyping converts the virtual designs from the 3dMDface™ System into a physical model by converting the data to a ZPrint (ZPR) CAD format file and a stereolithography (STL) file. The data, in conjunction with a Zprinter(®) 450 or a Stereolithography Apparatus (SLA), can be used to fabricate a model for prosthesis fabrication, without the disadvantages of the standard moulage technique. This article reviews this technique and how it can be applied to maxillofacial prosthetics. © 2011 by The American College of Prosthodontists.

  5. Prosthetically directed implant placement using computer software to ensure precise placement and predictable prosthetic outcomes. Part 2: rapid-prototype medical modeling and stereolithographic drilling guides requiring bone exposure.

    PubMed

    Rosenfeld, Alan L; Mandelaris, George A; Tardieu, Philippe B

    2006-08-01

    The purpose of this paper is to expand on part 1 of this series (published in the previous issue) regarding the emerging future of computer-guided implant dentistry. This article will introduce the concept of rapid-prototype medical modeling as well as describe the utilization and fabrication of computer-generated surgical drilling guides used during implant surgery. The placement of dental implants has traditionally been an intuitive process, whereby the surgeon relies on mental navigation to achieve optimal implant positioning. Through rapid-prototype medical modeling and the ste-reolithographic process, surgical drilling guides (eg, SurgiGuide) can be created. These guides are generated from a surgical implant plan created with a computer software system that incorporates all relevant prosthetic information from which the surgical plan is developed. The utilization of computer-generated planning and stereolithographically generated surgical drilling guides embraces the concept of collaborative accountability and supersedes traditional mental navigation on all levels of implant therapy.

  6. Rapid Prototyping as an Auxiliary in Mandibular Reconstructions.

    PubMed

    Sales, Pedro Henrique da Hora; Cetira Filho, Edson Luiz; Oliveira Neto, Jair Queiroz de; Silva, Julianne Coelho da; Aguiar, Andrea Silvia Walter de; Mello, Manoel de Jesus Rodrigues

    2017-09-25

    The reconstruction of mandible is a challenge with regard to aesthetic and reconstructive demands. The etiology of mandibular fractures is variable, trauma, pathology, bone infections. There are many materials that provide an excellent form of rehabilitation for these defects, where the autogenous graft presents important characteristics that favor a greater success rate. Furthermore, the rapid prototyping method is quite interesting, because it brings a series of advantages to the surgeon, like reducing the operative time, among others. The purpose of the present article is to describe a clinical case of a patient with mandible bone defect caused by gunshot perforation, treated through iliac crest bone graft with planning through rapid prototyping. The mandibular reconstruction can present a real challenge for the surgeon. Biomodels should be required in complex cases because they help to decrease surgical time and to increase the predictability of the procedure.

  7. Rapid prototype fabrication processes for high-performance thrust cells

    NASA Technical Reports Server (NTRS)

    Hunt, K.; Chwiedor, T.; Diab, J.; Williams, R.

    1994-01-01

    The Thrust Cell Technologies Program (Air Force Phillips Laboratory Contract No. F04611-92-C-0050) is currently being performed by Rocketdyne to demonstrate advanced materials and fabrication technologies which can be utilized to produce low-cost, high-performance thrust cells for launch and space transportation rocket engines. Under Phase 2 of the Thrust Cell Technologies Program (TCTP), rapid prototyping and investment casting techniques are being employed to fabricate a 12,000-lbf thrust class combustion chamber for delivery and hot-fire testing at Phillips Lab. The integrated process of investment casting directly from rapid prototype patterns dramatically reduces design-to-delivery cycle time, and greatly enhances design flexibility over conventionally processed cast or machined parts.

  8. Rapid prototyping for patient-specific surgical orthopaedics guides: A systematic literature review.

    PubMed

    Popescu, Diana; Laptoiu, Dan

    2016-06-01

    There has been a lot of hype surrounding the advantages to be gained from rapid prototyping processes in a number of fields, including medicine. Our literature review aims objectively to assess how effective patient-specific surgical guides manufactured using rapid prototyping are in a number of orthopaedic surgical applications. To this end, we carried out a systematic review to identify and analyse clinical and experimental literature studies in which rapid prototyping patient-specific surgical guides are used, focusing especially on those that entail quantifiable outcomes and, at the same time, providing details on the guides' design and type of manufacturing process. Here, it should be mentioned that in this field there are not yet medium- or long-term data, and no information on revisions. In the reviewed studies, the reported positive opinions on the use of rapid prototyping patient-specific surgical guides relate to the following main advantages: reduction in operating times, low costs and improvements in the accuracy of surgical interventions thanks to guides' personalisation. However, disadvantages and sources of errors which can cause patient-specific surgical guide failures are as well discussed by authors. Stereolithography is the main rapid prototyping process employed in these applications although fused deposition modelling or selective laser sintering processes can also satisfy the requirements of these applications in terms of material properties, manufacturing accuracy and construction time. Another of our findings was that individualised drill guides for spinal surgery are currently the favourite candidates for manufacture using rapid prototyping. Other emerging applications relate to complex orthopaedic surgery of the extremities: the forearm and foot. Several procedures such as osteotomies for radius malunions or tarsal coalition could become standard, thanks to the significant assistance provided by rapid prototyping patient-specific surgical

  9. Rapid prototyping with the visual data environment of an OFDM WLAN system

    NASA Astrophysics Data System (ADS)

    Serra, Moises; Marti, Pere; Carrabina, Jordi

    2005-06-01

    In this paper a rapid prototyping design flow is presented and applied to a prototype of the base-band physical layer of a Hiperlan/2 WLAN transceiver. This physical layer is a high performance multi-rate system that contains computationally intensive algorithms. A new method for prototyping the design flow and verifying the process is to use the latest generation of system level design environments (visual data flow environment) for DSPs. The System Generator and Matlab/Simulink tools form a visual data flow environment for FPGA allow us to model DSP systems and explore algorithms. This environment also translates designs into hardware implementations that are faithful, synthesizable and efficient, which can be explored and refined in rapid prototyping platforms.

  10. NASA Applied Sciences Program Rapid Prototyping Results and Conclusions

    NASA Astrophysics Data System (ADS)

    Cox, E. L.

    2007-12-01

    NASA's Applied Sciences Program seeks to expand the use of Earth science research results to benefit current and future operational systems tasked with making policy and management decisions. The Earth Science Division within the Science Mission Directorate sponsors over 1000 research projects annually to answer the fundamental research question: How is the Earth changing and what are the consequences for life on Earth? As research results become available, largely from satellite observations and Earth system model outputs, the Applied Sciences Program works diligently with scientists and researchers (internal and external to NASA) , and other government agency officials (USDA, EPA, CDC, DOE, US Forest Service, US Fish and Wildlife Service, DHS, USAID) to determine useful applications for these results in decision-making, ultimately benefiting society. The complexity of Earth science research results and the breadth of the Applied Sciences Program national priority areas dictate a broad scope and multiple approaches available to implement their use in decision-making. Over the past five years, the Applied Sciences Program has examined scientific and engineering practices and solicited the community for methods and steps that can lead to the enhancement of operational systems (Decision Support Systems - DSS) required for decision-making. In November 2006, the Applied Sciences Program launched an initiative aimed at demonstrating the applicability of NASA data (satellite observations, models, geophysical parameters from data archive centers) being incorporated into decision support systems and their related environments at a low cost and quick turnaround of results., i.e. designed rapid prototyping. Conceptually, an understanding of Earth science research (and results) coupled with decision-making requirements and needs leads to a demonstration (experiment) depicting enhancements or improvements to an operational decisions process through the use of NASA data. Five

  11. Rapid Prototyping of High Performance Signal Processing Applications

    NASA Astrophysics Data System (ADS)

    Sane, Nimish

    Advances in embedded systems for digital signal processing (DSP) are enabling many scientific projects and commercial applications. At the same time, these applications are key to driving advances in many important kinds of computing platforms. In this region of high performance DSP, rapid prototyping is critical for faster time-to-market (e.g., in the wireless communications industry) or time-to-science (e.g., in radio astronomy). DSP system architectures have evolved from being based on application specific integrated circuits (ASICs) to incorporate reconfigurable off-the-shelf field programmable gate arrays (FPGAs), the latest multiprocessors such as graphics processing units (GPUs), or heterogeneous combinations of such devices. We, thus, have a vast design space to explore based on performance trade-offs, and expanded by the multitude of possibilities for target platforms. In order to allow systematic design space exploration, and develop scalable and portable prototypes, model based design tools are increasingly used in design and implementation of embedded systems. These tools allow scalable high-level representations, model based semantics for analysis and optimization, and portable implementations that can be verified at higher levels of abstractions and targeted toward multiple platforms for implementation. The designer can experiment using such tools at an early stage in the design cycle, and employ the latest hardware at later stages. In this thesis, we have focused on dataflow-based approaches for rapid DSP system prototyping. This thesis contributes to various aspects of dataflow-based design flows and tools as follows: 1. We have introduced the concept of topological patterns, which exploits commonly found repetitive patterns in DSP algorithms to allow scalable, concise, and parameterizable representations of large scale dataflow graphs in high-level languages. We have shown how an underlying design tool can systematically exploit a high

  12. Rapid prototyping of microstructures by soft lithography for biotechnology.

    PubMed

    Wolfe, Daniel B; Qin, Dong; Whitesides, George M

    2010-01-01

    This chapter describes the methods and specific procedures used to fabricate microstructures by soft lithography. These techniques are useful for the prototyping of devices useful for applications in biotechnology. Fabrication by soft lithography does not require specialized or expensive equipment; the materials and facilities necessary are found commonly in biological and chemical laboratories in both academia and industry. The combination of the fact that the materials are low-cost and that the time from design to prototype device can be short (< 24 h) makes it possible to use and to screen rapidly devices that also can be disposable. Here we describe the procedures for fabricating microstructures with lateral dimensions as small as 1 mum. These types of microstructures are useful for microfluidic devices, cell-based assays, and bioengineered surfaces.

  13. Design and optimization of the micro-engine turbine rotor manufacturing using the rapid prototyping technology

    NASA Astrophysics Data System (ADS)

    Vdovin, R. A.; Smelov, V. G.

    2017-02-01

    This work describes the experience in manufacturing the turbine rotor for the micro-engine. It demonstrates the design principles for the complex investment casting process combining the use of the ProCast software and the rapid prototyping techniques. At the virtual modelling stage, in addition to optimized process parameters, the casting structure was improved to obtain the defect-free section. The real production stage allowed demonstrating the performance and fitness of rapid prototyping techniques for the manufacture of geometrically-complex engine-building parts.

  14. A novel technique for presurgical nasoalveolar molding using computer-aided reverse engineering and rapid prototyping.

    PubMed

    Yu, Quan; Gong, Xin; Wang, Guo-Min; Yu, Zhe-Yuan; Qian, Yu-Fen; Shen, Gang

    2011-01-01

    To establish a new method of presurgical nasoalveolar molding (NAM) using computer-aided reverse engineering and rapid prototyping technique in infants with unilateral cleft lip and palate (UCLP). Five infants (2 males and 3 females with mean age of 1.2 w) with complete UCLP were recruited. All patients were subjected to NAM before the cleft lip repair. The upper denture casts were recorded using a three-dimensional laser scanner within 2 weeks after birth in UCLP infants. A digital model was constructed and analyzed to simulate the NAM procedure with reverse engineering software. The digital geometrical data were exported to print the solid model with rapid prototyping system. The whole set of appliances was fabricated based on these solid models. Laser scanning and digital model construction simplified the NAM procedure and estimated the treatment objective. The appliances were fabricated based on the rapid prototyping technique, and for each patient, the complete set of appliances could be obtained at one time. By the end of presurgical NAM treatment, the cleft was narrowed, and the malformation of nasoalveolar segments was aligned normally. We have developed a novel technique of presurgical NAM based on a computer-aided design. The accurate digital denture model of UCLP infants could be obtained with laser scanning. The treatment design and appliance fabrication could be simplified with a computer-aided reverse engineering and rapid prototyping technique.

  15. Extending NASA Research Results to Benefit Society: Rapid Prototyping for Coastal Applications

    NASA Technical Reports Server (NTRS)

    Glorioso, Mark V.; Miller, Richard L.; Hall, Callie M.; McPherson, Terry R.

    2006-01-01

    The mission of the NASA Applied Sciences Program is to expand and accelerate the use of NASA research results to benefit society in 12 application areas of national priority. ONe of the program's major challenges is to perform a quick, efficient, and detailed review (i.e., prototyping) of the large number of combinations of NASA observations and results from Earth system models that may be used by a wide range of decision support tools. A Rapid Prototyping Capacity (RPC) is being developed to accelerate the use of NASA research results. Here, we present the conceptual framework of the Rapid Prototyping Capacity within the context of quickly assessing the efficacy of NASA research results and technologies to support the Coastal Management application. An initial RPC project designed to quickly evaluate the utility of moderate-resolution MODIS products for calibrating/validating coastal sediment transport models is also presented.

  16. Bio rapid prototyping by extruding/aspirating/refilling thermoreversible hydrogel.

    PubMed

    Iwami, K; Noda, T; Ishida, K; Morishima, K; Nakamura, M; Umeda, N

    2010-03-01

    This paper reports a method for rapid prototyping of cell tissues, which is based on a system that extrudes, aspirates and refills a mixture of cells and thermoreversible hydrogel as a scaffold. In the extruding mode, a cell-mixed scaffold solution in the sol state is extruded from a cooled micronozzle into a temperature-controlled substrate, which keeps the scaffold in the gel state. In the aspiration mode, the opposite process is performed by Bernoulli suction. In the refilling mode, the solution is extruded into a groove created in the aspiration mode. The minimum width of extruded hydrogel pattern is 114 +/- 15 microm by employing a nozzle of diameter 100 microm, and that of aspirated groove was 355 +/- 10 microm using a 500 microm-diameter nozzle. Gum arabic is mixed with the scaffold solution to avoid peeling-off of the gel pattern from the substrate. Patterning of Sf-9 cell tissue is demonstrated, and the stability of the patterned cell is investigated. This system offers a procedure for rapid prototyping and local modification of cell scaffolds for tissue engineering.

  17. Rapid Prototyping of Nanofluidic Slits in a Silicone Bilayer

    PubMed Central

    Kole, Thomas P.; Liao, Kuo-Tang; Schiffels, Daniel; Ilic, B. Robert; Strychalski, Elizabeth A.; Kralj, Jason G.; Liddle, J. Alexander; Dritschilo, Anatoly; Stavis, Samuel M.

    2015-01-01

    This article reports a process for rapidly prototyping nanofluidic devices, particularly those comprising slits with microscale widths and nanoscale depths, in silicone. This process consists of designing a nanofluidic device, fabricating a photomask, fabricating a device mold in epoxy photoresist, molding a device in silicone, cutting and punching a molded silicone device, bonding a silicone device to a glass substrate, and filling the device with aqueous solution. By using a bilayer of hard and soft silicone, we have formed and filled nanofluidic slits with depths of less than 400 nm and aspect ratios of width to depth exceeding 250 without collapse of the slits. An important attribute of this article is that the description of this rapid prototyping process is very comprehensive, presenting context and details which are highly relevant to the rational implementation and reliable repetition of the process. Moreover, this process makes use of equipment commonly found in nanofabrication facilities and research laboratories, facilitating the broad adaptation and application of the process. Therefore, while this article specifically informs users of the Center for Nanoscale Science and Technology (CNST) at the National Institute of Standards and Technology (NIST), we anticipate that this information will be generally useful for the nanofabrication and nanofluidics research communities at large, and particularly useful for neophyte nanofabricators and nanofluidicists. PMID:26958449

  18. Rapid Prototyping of Nanofluidic Slits in a Silicone Bilayer.

    PubMed

    Kole, Thomas P; Liao, Kuo-Tang; Schiffels, Daniel; Ilic, B Robert; Strychalski, Elizabeth A; Kralj, Jason G; Liddle, J Alexander; Dritschilo, Anatoly; Stavis, Samuel M

    2015-01-01

    This article reports a process for rapidly prototyping nanofluidic devices, particularly those comprising slits with microscale widths and nanoscale depths, in silicone. This process consists of designing a nanofluidic device, fabricating a photomask, fabricating a device mold in epoxy photoresist, molding a device in silicone, cutting and punching a molded silicone device, bonding a silicone device to a glass substrate, and filling the device with aqueous solution. By using a bilayer of hard and soft silicone, we have formed and filled nanofluidic slits with depths of less than 400 nm and aspect ratios of width to depth exceeding 250 without collapse of the slits. An important attribute of this article is that the description of this rapid prototyping process is very comprehensive, presenting context and details which are highly relevant to the rational implementation and reliable repetition of the process. Moreover, this process makes use of equipment commonly found in nanofabrication facilities and research laboratories, facilitating the broad adaptation and application of the process. Therefore, while this article specifically informs users of the Center for Nanoscale Science and Technology (CNST) at the National Institute of Standards and Technology (NIST), we anticipate that this information will be generally useful for the nanofabrication and nanofluidics research communities at large, and particularly useful for neophyte nanofabricators and nanofluidicists.

  19. Application of Rapid Prototyping Methods to High-Speed Wind Tunnel Testing

    NASA Technical Reports Server (NTRS)

    Springer, A. M.

    1998-01-01

    This study was undertaken in MSFC's 14-Inch Trisonic Wind Tunnel to determine if rapid prototyping methods could be used in the design and manufacturing of high speed wind tunnel models in direct testing applications, and if these methods would reduce model design/fabrication time and cost while providing models of high enough fidelity to provide adequate aerodynamic data, and of sufficient strength to survive the test environment. Rapid prototyping methods utilized to construct wind tunnel models in a wing-body-tail configuration were: fused deposition method using both ABS plastic and PEEK as building materials, stereolithography using the photopolymer SL-5170, selective laser sintering using glass reinforced nylon, and laminated object manufacturing using plastic reinforced with glass and 'paper'. This study revealed good agreement between the SLA model, the metal model with an FDM-ABS nose, an SLA nose, and the metal model for most operating conditions, while the FDM-ABS data diverged at higher loading conditions. Data from the initial SLS model showed poor agreement due to problems in post-processing, resulting in a different configuration. A second SLS model was tested and showed relatively good agreement. It can be concluded that rapid prototyping models show promise in preliminary aerodynamic development studies at subsonic, transonic, and supersonic speeds.

  20. Advanced rapid prototyping by laser beam sintering of metal prototypes: design and development of an optimized laser beam delivery system

    NASA Astrophysics Data System (ADS)

    Geiger, Manfred; Coremans, A.; Neubauer, Norbert; Niebling, F.

    1996-08-01

    Fast technological advances and steadily increasing severe worldwide competition force industry to respond all the time faster to new and chanced customer wishes. Some of the recently emerged processes, commonly referred to as 'rapid prototyping' (RP), have proved to be powerful tools for accelerating product and process development. Early approaches aimed at the automated production of plastic models. These techniques achieved industrial maturity extremely fast and are meanwhile established as standard utilities in the field of development/design processes. So far, their applicability to metal working industry was limited to design studies because the mechanical properties of the prototypes, e.g. modulus of elasticity and mechanical strength were not comparable to the final products they represented. Therefore, RP-processes aimed at the direct production of metallic prototypes gained more and more importance during recent years. A technique belonging to this group is manufacturing of prototypes by using a laser beam sintering machine capable of directly processing metal powders. This so called laser beam sintering process showed a great potential for direct manufacturing of functional tools and prototypes in early feasibility studies. Detailed examinations were performed at several research centers to determine the attainable quality of the parts concerning roughness, dimensional accuracy and mechanical strength. These examinations showed, that there still is a considerable demand for quality improvements of the previously mentioned parameters. The practical application and the potential for improvement of the geometrical accuracy of laser beam sintered parts by using a dual beam concept was proven. An innovative beam guiding and forming concept, similar to the previously mentioned patented beam guiding system, was developed and built with the goal to improve the process parameters governing mechanical properties as well as geometrical accuracy. Further reaching

  1. Rapid development of auricular prosthesis using CAD and rapid prototyping technologies.

    PubMed

    Subburaj, K; Nair, C; Rajesh, S; Meshram, S M; Ravi, B

    2007-10-01

    External ear defects can be corrected by surgery, but this may not be feasible for personal or medical reasons. Reconstructive solutions are a good alternative, but rely on the artistry and availability of the anaplastologist. A semi-automated methodology using computer-aided design (CAD) and rapid prototyping (RP) technologies was developed for auricular prosthesis development, and demonstrated in a real-life case. The correct geometry and position of the prosthesis were ensured by stacking the computed tomography scan images of the contralateral normal ear in reverse order, and joining them using a medical modelling software program. The CAD model of the remnant portion of the defective ear was subtracted from the model of the mirrored contralateral ear, using a haptic CAD system, to obtain the final geometry of the prosthesis. Polymer models were fabricated in RP systems, and used for making a corresponding mould. Medical grade silicone rubber of the appropriate colour was packed into the mould to fabricate the final ear prosthesis and fitted to the deficient side of the patient using medical grade adhesive. The computer-aided methodology gave a high level of accuracy in terms of shape, size and position of the prosthesis, and a significantly shorter lead time compared to the conventional (manual) technique.

  2. Performance of a Micro-UAV lifting system built with the usage of rapid prototyping methods

    NASA Astrophysics Data System (ADS)

    Dalewski, R. T.; Gumowski, K.; Barczak, T.; Godek, J.

    2014-08-01

    This article presents results of the aerodynamic testing of a micro unmanned aerial vehicle rotor efficiency. The rotors were prepared as a set of two rotors in a counter-rotating ducted drive. Prototypes of the drives were made using two rapid prototyping techniques - FDM - fused deposition modelling method and SLS - selective laser sintering. Rotors were made then treated by introducing additional finishing cyanoacrylate coating and abrasive processing. Main differences between those models were observed in fan shape, porosity, surface roughness and mechanical properties - stiffness. An influence of these factors was observed on an aerodynamic efficiency. For the obtained prototypes both simulations and experimental testing were conducted with thrust, power, torque measurements, as well as the measurement of velocity and pressure distribution at the outlet of the duct. The results show the possibility of using rapid prototyping techniques to produce prototypes of drives operating in the low and medium Reynolds numbers (6000-60000), and the aerodynamic shape relevant factors affecting the preparation and performance of such drives. In addition, simulation studies were performed using the Fluent environment where experimental results were confronted with the results of simulation studies.

  3. Rapid laser prototyping of valves for microfluidic autonomous systems

    NASA Astrophysics Data System (ADS)

    Mohammed, M. I.; Abraham, E.; Y Desmulliez, M. P.

    2013-03-01

    Capillary forces in microfluidics provide a simple yet elegant means to direct liquids through flow channel networks. The ability to manipulate the flow in a truly automated manner has proven more problematic. The majority of valves require some form of flow control devices, which are manually, mechanically or electrically driven. Most demonstrated capillary systems have been manufactured by photolithography, which, despite its high precision and repeatability, can be labour intensive, requires a clean room environment and the use of fixed photomasks, limiting thereby the agility of the manufacturing process to readily examine alternative designs. In this paper, we describe a robust and rapid CO2 laser manufacturing process and demonstrate a range of capillary-driven microfluidic valve structures embedded within a microfluidic network. The manufacturing process described allows for advanced control and manipulation of fluids such that flow can be halted, triggered and delayed based on simple geometrical alterations to a given microchannel. The rapid prototyping methodology has been employed with PMMA substrates and a complete device has been created, ready for use, within 2-3 h. We believe that this agile manufacturing process can be applied to produce a range of complex autonomous fluidic platforms and allows subsequent designs to be rapidly explored.

  4. Rapid prototyping in tissue engineering: challenges and potential.

    PubMed

    Yeong, Wai-Yee; Chua, Chee-Kai; Leong, Kah-Fai; Chandrasekaran, Margam

    2004-12-01

    Tissue engineering aims to produce patient-specific biological substitutes in an attempt to circumvent the limitations of existing clinical treatments for damaged tissue or organs. The main regenerative tissue engineering approach involves transplantation of cells onto scaffolds. The scaffold attempts to mimic the function of the natural extracellular matrix, providing a temporary template for the growth of target tissues. Scaffolds should have suitable architecture and strength to serve their intended function. This paper presents a comprehensive review of the fabrication methods, including conventional, mainly manual, techniques and advanced processing methods such as rapid prototyping (RP) techniques. The potential and challenges of scaffold-based technology are discussed from the perspective of RP technology.

  5. GAJAT A Rapid Prototyping Mission Architecture Tool with Embedded Costing

    NASA Technical Reports Server (NTRS)

    Gerber, Andrew J.; Crawford, John P.

    2004-01-01

    GAJAT is a Near Earth Mission Architecture (NEMA) Rapid Prototyping Analysis Tool. It Was designed to be operated by a single systems engineer to replicate the mission design output of JPL's Team X. GAJAT provides estimates for: (1) The overall design of an observatory with a defined payload [instrument(s)] (2) The spacecraft consumable resources required to support the mission over its specified operational period (3) The minimum launch vehicle capability requirement (4) The Ground Segment Requirements, and (5) The cost for developing and launching the observatory (mission development cost) and the cost to operate the system over the specified operational period (mission operations cost), the sum of these two being the total mission cost.

  6. Rapid, Reliable Shape Setting of Superelastic Nitinol for Prototyping Robots.

    PubMed

    Gilbert, Hunter B; Webster, Robert J

    Shape setting Nitinol tubes and wires in a typical laboratory setting for use in superelastic robots is challenging. Obtaining samples that remain superelastic and exhibit desired precurvatures currently requires many iterations, which is time consuming and consumes a substantial amount of Nitinol. To provide a more accurate and reliable method of shape setting, in this paper we propose an electrical technique that uses Joule heating to attain the necessary shape setting temperatures. The resulting high power heating prevents unintended aging of the material and yields consistent and accurate results for the rapid creation of prototypes. We present a complete algorithm and system together with an experimental analysis of temperature regulation. We experimentally validate the approach on Nitinol tubes that are shape set into planar curves. We also demonstrate the feasibility of creating general space curves by shape setting a helical tube. The system demonstrates a mean absolute temperature error of 10°C.

  7. GAJAT A Rapid Prototyping Mission Architecture Tool with Embedded Costing

    NASA Technical Reports Server (NTRS)

    Gerber, Andrew J.; Crawford, John P.

    2004-01-01

    GAJAT is a Near Earth Mission Architecture (NEMA) Rapid Prototyping Analysis Tool. It Was designed to be operated by a single systems engineer to replicate the mission design output of JPL's Team X. GAJAT provides estimates for: (1) The overall design of an observatory with a defined payload [instrument(s)] (2) The spacecraft consumable resources required to support the mission over its specified operational period (3) The minimum launch vehicle capability requirement (4) The Ground Segment Requirements, and (5) The cost for developing and launching the observatory (mission development cost) and the cost to operate the system over the specified operational period (mission operations cost), the sum of these two being the total mission cost.

  8. Rapid, Reliable Shape Setting of Superelastic Nitinol for Prototyping Robots

    PubMed Central

    Gilbert, Hunter B.; Webster, Robert J.

    2016-01-01

    Shape setting Nitinol tubes and wires in a typical laboratory setting for use in superelastic robots is challenging. Obtaining samples that remain superelastic and exhibit desired precurvatures currently requires many iterations, which is time consuming and consumes a substantial amount of Nitinol. To provide a more accurate and reliable method of shape setting, in this paper we propose an electrical technique that uses Joule heating to attain the necessary shape setting temperatures. The resulting high power heating prevents unintended aging of the material and yields consistent and accurate results for the rapid creation of prototypes. We present a complete algorithm and system together with an experimental analysis of temperature regulation. We experimentally validate the approach on Nitinol tubes that are shape set into planar curves. We also demonstrate the feasibility of creating general space curves by shape setting a helical tube. The system demonstrates a mean absolute temperature error of 10°C. PMID:27648473

  9. Rapid SOA Frontend Design and Prototyping for LINC-NIRVANA

    NASA Astrophysics Data System (ADS)

    Berwein, J.; Briegel, F.; Kittmann, F.; Pavlov, A.; Gaessler, W.; Kittmann, F.

    2010-12-01

    LINC-NIRVANA is a German-Italian Fizeau (imaging) interferometer for the Large Binocular Telescope (LBT) on Mt. Graham in Arizona, USA. For laboratory testing and integration, a large number of engineering applications are needed. The process of engineering, testing and integration has to go hand in hand with an agile software development for data display and configuration frontends. Therefore we implemented software packages, which enable a rapid design and prototyping of engineering applications within an SOA oriented environment. Due to the usage of only pre-compiled software and the easy to handle workflow neither compilation nor programming knowledge is require. We will present the current development status, usage and advantages of our software, which was realized at the Max Planck Institute for Astronomy in Heidelberg, Germany.

  10. Advanced Propulsion and TPS for a Rapidly-Prototyped CEV

    NASA Astrophysics Data System (ADS)

    Hudson, Gary C.

    2005-02-01

    Transformational Space Corporation (t/Space) is developing for NASA the initial designs for the Crew Exploration Vehicle family, focusing on a Launch CEV for transporting NASA and civilian passengers from Earth to orbit. The t/Space methodology is rapid prototyping of major vehicle systems, and deriving detailed specifications from the resulting hardware, avoiding "written-in-advance" specs that can force the costly invention of new capabilities simply to meet such specs. A key technology shared by the CEV family is Vapor Pressurized propulsion (Vapak) for simplicity and reliability, which provides electrical power, life support gas and a heat sink in addition to propulsion. The CEV family also features active transpiration cooling of re-entry surfaces (for reusability) backed up by passive thermal protection.

  11. An FPGA-based rapid prototyping platform for wavelet coprocessors

    NASA Astrophysics Data System (ADS)

    Vera, Alonzo; Meyer-Baese, Uwe; Pattichis, Marios

    2007-04-01

    MatLab/Simulink-based design flows are being used by DSP designers to improve time-to-market of FPGA implementations. 1 Commonly, digital signal processing cores are integrated in an embedded system as coprocessors. Existing CAD tools do not fully address the integration of a DSP coprocessor into an embedded system design. This integration might prove to be time consuming and error prone. It also requires that the DSP designer has an excellent knowledge of embedded systems and computer architecture details. We present a prototyping platform and design flow that allows rapid integration of embedded systems with a wavelet coprocessor. The platform comprises of software and hardware modules that allow a DSP designer a painless integration of a coprocessor with a PowerPC-based embedded system. The platform has a wide range of applications, from industrial to educational environments.

  12. Modeling mechanical signals on the surface of µCT and CAD based rapid prototype scaffold models to predict (early stage) tissue development.

    PubMed

    Hendrikson, W J; van Blitterswijk, C A; Verdonschot, N; Moroni, L; Rouwkema, J

    2014-09-01

    In the field of tissue engineering, mechano-regulation theories have been applied to help predict tissue development in tissue engineering scaffolds in the past. For this, finite element models (FEMs) were used to predict the distribution of strains within a scaffold. However, the strains reported in these studies are volumetric strains of the material or strains developed in the extracellular matrix occupying the pore space. The initial phase of cell attachment and growth on the biomaterial surface has thus far been neglected. In this study, we present a model that determines the magnitude of biomechanical signals on the biomaterial surface, enabling us to predict cell differentiation stimulus values at this initial stage. Results showed that magnitudes of the 2D strain--termed surface strain--were lower when compared to the 3D volumetric strain or the conventional octahedral shear strain as used in current mechano-regulation theories. Results of both µCT and CAD derived FEMs from the same scaffold were compared. Strain and fluid shear stress distributions, and subsequently the cell differentiation stimulus, were highly dependent on the pore shape. CAD models were not able to capture the distributions seen in the µCT FEM. The calculated mechanical stimuli could be combined with current mechanobiological models resulting in a tool to predict cell differentiation in the initial phase of tissue engineering. Although experimental data is still necessary to properly link mechanical signals to cell behavior in this specific setting, this model is an important step towards optimizing scaffold architecture and/or stimulation regimes.

  13. Print your own membrane: direct rapid prototyping of polydimethylsiloxane.

    PubMed

    Femmer, Tim; Kuehne, Alexander J C; Wessling, Matthias

    2014-08-07

    Polydimethylsiloxane is a translucent and biologically inert silicone material used in sealants, biomedical implants and microscale lab-on-a-chip devices. Furthermore, in membrane technology, polydimethylsiloxane represents a material for separation barriers as it has high permeabilities for various gases. The facile handling of two component formulations with a silicone base material, a catalyst and a small molecular weight crosslinker makes it widely applicable for soft-lithographic replication of two-dimensional device geometries, such as microfluidic chips or micro-contact stamps. Here, we develop a new technique to directly print polydimethylsiloxane in a rapid prototyping device, circumventing the need for masks or sacrificial mold production. We create a three-dimensional polydimethylsiloxane membrane for gas-liquid-contacting based on a Schwarz-P triple-periodic minimal-surface, which is inaccessible with common machining techniques. Direct 3D-printing of polydimethylsiloxane enables rapid production of novel chip geometries for a manifold of lab-on-a-chip applications.

  14. Rapid Prototyping of Continuous Fiber Reinforced Ceramic Matrix Composites

    NASA Technical Reports Server (NTRS)

    Vaidyanathan, R.; Green, C.; Phillips, T.; Cipriani, R.; Yarlagadda, S.; Gillespie, J. W., Jr.; Effinger, M.; Cooper, K. C.

    2003-01-01

    For ceramics to be used as structural components in high temperature applications, their fracture toughness is improved by embedding continuous ceramic fibers. Ceramic matrix composite (CMC) materials allow increasing the overall operating temperature, raising the temperature safety margins, avoiding the need for cooling, and improving the damping capacity, while reducing the weight at the same time. They also need to be reliable and available in large quantities as well. In this paper, an innovative rapid prototyping technique to fabricate continuous fiber reinforced ceramic matrix composites is described. The process is simple, robust and will be widely applicable to a number of high temperature material systems. This technique was originally developed at the University of Delaware Center for Composite Materials (UD-CCM) for rapid fabrication of polymer matrix composites by a technique called automated tow placement or ATP. The results of mechanical properties and microstructural characterization are presented, together with examples of complex shapes and parts. It is believed that the process will be able to create complex shaped parts at an order of magnitude lower cost than current chemical vapor infiltration (CVI) and polymer impregnation and pyrolysis (PIP) processes.

  15. Rapid Prototyping of Continuous Fiber Reinforced Ceramic Matrix Composites

    NASA Technical Reports Server (NTRS)

    Vaidyanathan, R.; Green, C.; Phillips, T.; Cipriani, R.; Yarlagadda, S.; Gillespie, J.; Effinger, M.; Cooper, K. C.; Gordon, Gail (Technical Monitor)

    2002-01-01

    For ceramics to be used as structural components in high temperature applications, their fracture toughness is improved by embedding continuous ceramic fibers. Ceramic matrix composite (CMC) materials allow increasing the overall operating temperature, raising the temperature safety margins, avoiding the need for cooling, and improving the damping capacity, while reducing the weight at the same time. They also need to be reliable and available in large quantities as well. In this paper, an innovative rapid prototyping technique to fabricate continuous fiber reinforced ceramic matrix composites is described. The process is simple, robust and will be widely applicable to a number of high temperature material systems. This technique was originally developed at the University of Delaware Center for Composite Materials (UD-CCM) for rapid fabrication of polymer matrix composites by a technique called automated tow placement or ATP. The results of mechanical properties and microstructural characterization are presented, together with examples of complex shapes and parts. It is believed that the process will be able to create complex shaped parts at an order of magnitude lower cost than current CVI and PIP processes.

  16. Rapid prototyping of PDMS devices using SU-8 lithography.

    PubMed

    Jenkins, Gareth

    2013-01-01

    This protocol describes the fabrication of single and multi-layer SU-8 microstructures for generating microfluidic devices via PDMS (polymethyldisiloxane) casting. SU-8 is a negative, thick-film, epoxy based photoresist that has become widespread in the MEMS industry for producing durable, high aspect ratio microstructures for a variety of applications. It has become especially popular with microfluidics researchers to produce molds for PDMS casting since such molds allow for the rapid replication of prototype microfluidic structures made from PDMS. Although SU-8 processing does allow for rapid and straightforward development of devices it is prone to numerous pitfalls which have gained it a reputation of being somewhat of a "black art." This protocol attempts to give as full an account as possible of all the tricks and tips the author has learned over the years for processing SU-8. It also describes the casting of PDMS and plasma bonding for the generation of complete microfluidic devices ready for use in the lab.

  17. An Example of Economic Value in Rapid Prototyping

    NASA Technical Reports Server (NTRS)

    Hauer, R. L.; Braunscheidel, E. P.

    2001-01-01

    Today's modern machining projects are composed more and more of complicated and intricate structure due to a variety of reasons including the ability to computer model complex surfaces and forms. The cost of producing these forms can be extremely high not only in dollars but in time to complete. Changes are even more difficult to incorporate. The subject blade shown is an excellent example. Its complex form would have required hundreds of hours in fabrication for just a simple prototype. The procurement would have taken in the neighborhood of six weeks to complete. The actual fabrication would have been an equal amount of time to complete. An alternative to this process would have been a wood model. Although cheaper than a metal fabrication, it would be extremely time intensive and require in the neighborhood of a month to produce in-house.

  18. Preliminary work toward the development of a dimensional tolerance standard for rapid prototyping

    NASA Technical Reports Server (NTRS)

    Kennedy, W. J.

    1996-01-01

    Rapid prototyping is a new technology for building parts quickly from CAD models. It works by slicing a CAD model into layers, then by building a model of the part one layer at a time. Since most parts can be sliced, most parts can be modeled using rapid prototyping. The layers themselves are created in a number of different ways - by using a laser to cure a layer of an epoxy or a resin, by depositing a layer of plastic or wax upon a surface, by using a laser to sinter a layer of powder, or by using a laser to cut a layer of paper. Rapid prototyping (RP) is new, and a standard part for use in comparing dimensional tolerances has not yet been chosen and accepted by ASTM (the American Society for Testing Materials). Such a part is needed when RP is used to build parts for investment casting or for direct use. The objective of this project was to start the development of a standard part by using statistical techniques to choose the features of the part which show curl - the vertical deviation of a part from its intended horizontal plane.

  19. Rapid prototyping technology in orbital floor reconstruction: application in three patients.

    PubMed

    Lim, Christopher G T; Campbell, Duncan I; Clucas, Don M

    2014-06-01

    Rapid prototyping entails the fabrication of three-dimensional anatomical models which provide an accurate and cost-effective method to visualize complex anatomical structures. Our unit has been using this to assist in the diagnosis, planning, and preoperative titanium plate adaptation for orbital reconstruction surgery following traumatic injury. The aim of this article is to demonstrate the potential clinical and cost-saving benefits of this technology.

  20. Rapid Prototyping Technology in Orbital Floor Reconstruction: Application in Three Patients

    PubMed Central

    Lim, Christopher G. T.; Campbell, Duncan I.; Clucas, Don M.

    2014-01-01

    Rapid prototyping entails the fabrication of three-dimensional anatomical models which provide an accurate and cost-effective method to visualize complex anatomical structures. Our unit has been using this to assist in the diagnosis, planning, and preoperative titanium plate adaptation for orbital reconstruction surgery following traumatic injury. The aim of this article is to demonstrate the potential clinical and cost-saving benefits of this technology. PMID:25050149

  1. Command and Control Rapid Prototyping Continuum (C2RPC) Transition: Bridging the Valley of Death

    DTIC Science & Technology

    2011-04-30

    development model that aligns with the new information technology (IT) acquisition cycle and bridges the software transition valley of death. It...prototype development and transition processes needed to rapidly develop, test, and field new software technologies . Uniting the various stakeholders, the... Technologies developed under the U.S. Navy?s science and technology (S&T) umbrella have historically had only moderate success transitioning to Navy

  2. Risk D&D Rapid Prototype: Scenario Documentation and Analysis Tool

    SciTech Connect

    Unwin, Stephen D.; Seiple, Timothy E.

    2009-05-28

    Report describes process and methodology associated with a rapid prototype tool for integrating project risk analysis and health & safety risk analysis for decontamination and decommissioning projects.

  3. Airplane numerical simulation for the rapid prototyping process

    NASA Astrophysics Data System (ADS)

    Roysdon, Paul F.

    Airplane Numerical Simulation for the Rapid Prototyping Process is a comprehensive research investigation into the most up-to-date methods for airplane development and design. Uses of modern engineering software tools, like MatLab and Excel, are presented with examples of batch and optimization algorithms which combine the computing power of MatLab with robust aerodynamic tools like XFOIL and AVL. The resulting data is demonstrated in the development and use of a full non-linear six-degrees-of-freedom simulator. The applications for this numerical tool-box vary from un-manned aerial vehicles to first-order analysis of manned aircraft. A Blended-Wing-Body airplane is used for the analysis to demonstrate the flexibility of the code from classic wing-and-tail configurations to less common configurations like the blended-wing-body. This configuration has been shown to have superior aerodynamic performance -- in contrast to their classic wing-and-tube fuselage counterparts -- and have reduced sensitivity to aerodynamic flutter as well as potential for increased engine noise abatement. Of course without a classic tail elevator to damp the nose up pitching moment, and the vertical tail rudder to damp the yaw and possible rolling aerodynamics, the challenges in lateral roll and yaw stability, as well as pitching moment are not insignificant. This thesis work applies the tools necessary to perform the airplane development and optimization on a rapid basis, demonstrating the strength of this tool through examples and comparison of the results to similar airplane performance characteristics published in literature.

  4. Indirect rapid prototyping of antibacterial acid anhydride copolymer microneedles.

    PubMed

    Boehm, Ryan D; Miller, Philip R; Singh, Ritika; Shah, Akash; Stafslien, Shane; Daniels, Justin; Narayan, Roger J

    2012-03-01

    Microneedles are needle-like projections with microscale features that may be used for transdermal delivery of a variety of pharmacologic agents, including antibacterial agents. In the study described in this paper, an indirect rapid prototyping approach involving a combination of visible light dynamic mask micro-stereolithography and micromolding was used to prepare microneedle arrays out of a biodegradable acid anhydride copolymer, Gantrez(®) AN 169 BF. Fourier transform infrared spectroscopy, energy dispersive x-ray spectrometry and nanoindentation studies were performed to evaluate the chemical and mechanical properties of the Gantrez(®) AN 169 BF material. Agar plating studies were used to evaluate the in vitro antimicrobial performance of these arrays against Bacillus subtilis, Candida albicans, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. Large zones of growth inhibition were noted for Escherichia coli, S. aureus, Enterococcus faecalis and B. subtilis. The performance of Gantrez(®) AN 169 BF against several bacteria suggests that biodegradable acid anhydride copolymer microneedle arrays prepared using visible light dynamic mask micro-stereolithography micromolding may be useful for treating a variety of skin infections.

  5. Inorganic polymers: morphogenic inorganic biopolymers for rapid prototyping chain.

    PubMed

    Müller, Werner E G; Schröder, Heinz C; Shen, Zhijian; Feng, Qingling; Wang, Xiaohong

    2013-01-01

    In recent years, considerable progress has been achieved towards the development of customized scaffold materials, in particular for bone tissue engineering and repair, by the introduction of rapid prototyping or solid freeform fabrication techniques. These new fabrication techniques allow to overcome many problems associated with conventional bone implants, such as inadequate external morphology and internal architecture, porosity and interconnectivity, and low reproducibility. However, the applicability of these new techniques is still hampered by the fact that high processing temperature or a postsintering is often required to increase the mechanical stability of the generated scaffold, as well as a post-processing, i.e., surface modification/functionalization to enhance the biocompatibility of the scaffold or to bind some bioactive component. A solution might be provided by the introduction of novel inorganic biopolymers, biosilica and polyphosphate, which resist harsh conditions applied in the RP chain and are morphogenetically active and do not need supplementation by growth factors/cytokines to stimulate the growth and the differentiation of bone-forming cells.

  6. Towards rapid prototyped convective microfluidic DNA amplification platform

    NASA Astrophysics Data System (ADS)

    Ajit, Smrithi; Praveen, Hemanth Mithun; Puneeth, S. B.; Dave, Abhishek; Sesham, Bharat; Mohan, K. N.; Goel, Sanket

    2017-02-01

    Today, Polymerase Chain Reaction (PCR) based DNA amplification plays an indispensable role in the field of biomedical research. Its inherent ability to exponentially amplify sample DNA has proven useful for the identification of virulent pathogens like those causing Multiple Drug-Resistant Tuberculosis (MDR-TB). The intervention of Microfluidics technology has revolutionized the concept of PCR from being a laborious and time consuming process into one that is faster, easily portable and capable of being multifunctional. The Microfluidics based PCR outweighs its traditional counterpart in terms of flexibility of varying reaction rate, operation simplicity, need of a fraction of volume and capability of being integrated with other functional elements. The scope of the present work involves the development of a real-time continuous flow microfluidic device, fabricated by 3D printing-governed rapid prototyping method, eventually leading to an automated and robust platform to process multiple DNA samples for detection of MDRTB-associated mutations. The thermal gradient characteristic to the PCR process is produced using peltier units appropriate to the microfluidic environment fully monitored and controlled by a low cost controller driven by a Data Acquisition System. The process efficiency achieved in the microfluidic environment in terms of output per cycle is expected to be on par with the traditional PCR and capable of earning the additional advantages of being faster and minimizing the handling.

  7. Rapid prototyping of biomimetic vascular phantoms for hyperspectral reflectance imaging

    PubMed Central

    Ghassemi, Pejhman; Wang, Jianting; Melchiorri, Anthony J.; Ramella-Roman, Jessica C.; Mathews, Scott A.; Coburn, James C.; Sorg, Brian S.; Chen, Yu; Joshua Pfefer, T.

    2015-01-01

    Abstract. The emerging technique of rapid prototyping with three-dimensional (3-D) printers provides a simple yet revolutionary method for fabricating objects with arbitrary geometry. The use of 3-D printing for generating morphologically biomimetic tissue phantoms based on medical images represents a potentially major advance over existing phantom approaches. Toward the goal of image-defined phantoms, we converted a segmented fundus image of the human retina into a matrix format and edited it to achieve a geometry suitable for printing. Phantoms with vessel-simulating channels were then printed using a photoreactive resin providing biologically relevant turbidity, as determined by spectrophotometry. The morphology of printed vessels was validated by x-ray microcomputed tomography. Channels were filled with hemoglobin (Hb) solutions undergoing desaturation, and phantoms were imaged with a near-infrared hyperspectral reflectance imaging system. Additionally, a phantom was printed incorporating two disjoint vascular networks at different depths, each filled with Hb solutions at different saturation levels. Light propagation effects noted during these measurements—including the influence of vessel density and depth on Hb concentration and saturation estimates, and the effect of wavelength on vessel visualization depth—were evaluated. Overall, our findings indicated that 3-D-printed biomimetic phantoms hold significant potential as realistic and practical tools for elucidating light–tissue interactions and characterizing biophotonic system performance. PMID:26662064

  8. Rapid prototyping of biomimetic vascular phantoms for hyperspectral reflectance imaging

    NASA Astrophysics Data System (ADS)

    Ghassemi, Pejhman; Wang, Jianting; Melchiorri, Anthony J.; Ramella-Roman, Jessica C.; Mathews, Scott A.; Coburn, James C.; Sorg, Brian S.; Chen, Yu; Joshua Pfefer, T.

    2015-12-01

    The emerging technique of rapid prototyping with three-dimensional (3-D) printers provides a simple yet revolutionary method for fabricating objects with arbitrary geometry. The use of 3-D printing for generating morphologically biomimetic tissue phantoms based on medical images represents a potentially major advance over existing phantom approaches. Toward the goal of image-defined phantoms, we converted a segmented fundus image of the human retina into a matrix format and edited it to achieve a geometry suitable for printing. Phantoms with vessel-simulating channels were then printed using a photoreactive resin providing biologically relevant turbidity, as determined by spectrophotometry. The morphology of printed vessels was validated by x-ray microcomputed tomography. Channels were filled with hemoglobin (Hb) solutions undergoing desaturation, and phantoms were imaged with a near-infrared hyperspectral reflectance imaging system. Additionally, a phantom was printed incorporating two disjoint vascular networks at different depths, each filled with Hb solutions at different saturation levels. Light propagation effects noted during these measurements-including the influence of vessel density and depth on Hb concentration and saturation estimates, and the effect of wavelength on vessel visualization depth-were evaluated. Overall, our findings indicated that 3-D-printed biomimetic phantoms hold significant potential as realistic and practical tools for elucidating light-tissue interactions and characterizing biophotonic system performance.

  9. Rapid prototyping for radio-frequency geolocation applications

    SciTech Connect

    Briles, S. C.; Arrowood, J. L.; Braun, T. R.; Turcotte, D.; Fiset, E.

    2004-01-01

    Previous space-to-ground, single-platform geolocation experiments exploiting time-difference-of arrival (TDOA) via interferometry were successful at separating and quantitatively characterizing interfering radio frequency (RF) signals from expected RF transmissions. Much of the success of these experiments rested on the use of embedded processors to perform the required signal processing. The experiments handled data in a 'snapshot' fashion: digitized data was collected, the data was processed via a digital signal processing (DSP) microprocessor to yield differential phase measurements, and these measurements were transmitted to the Earth for geolocation processing. With the utilization of FPGAs (field programmable gate arrays) for the intensive number-crunching algorithms, the processing of streaming real-time data is feasible for bandwidths on the order of 20 MHz. By partitioning the signal processing algorithm so there is a significant reduction in the data rate as data flows through the FPGA, a DSP microprocessor can now be employed to perform further decision-oriented processing on the FPGA output. This hybrid architecture, employing both FPGAs and DSPs, typically requires an expensive and lengthy development cycle. However, the use of graphical development environments with auto-code generation and hardware-in-the-loop testing can result in rapid prototyping for geolocation experiments, which enables adaptation to emerging signals of interest in a cost and time effective manner.

  10. Integrated flexible manufacturing program for manufacturing automation and rapid prototyping

    NASA Technical Reports Server (NTRS)

    Brooks, S. L.; Brown, C. W.; King, M. S.; Simons, W. R.; Zimmerman, J. J.

    1993-01-01

    The Kansas City Division of Allied Signal Inc., as part of the Integrated Flexible Manufacturing Program (IFMP), is developing an integrated manufacturing environment. Several systems are being developed to produce standards and automation tools for specific activities within the manufacturing environment. The Advanced Manufacturing Development System (AMDS) is concentrating on information standards (STEP) and product data transfer; the Expert Cut Planner system (XCUT) is concentrating on machining operation process planning standards and automation capabilities; the Advanced Numerical Control system (ANC) is concentrating on NC data preparation standards and NC data generation tools; the Inspection Planning and Programming Expert system (IPPEX) is concentrating on inspection process planning, coordinate measuring machine (CMM) inspection standards and CMM part program generation tools; and the Intelligent Scheduling and Planning System (ISAPS) is concentrating on planning and scheduling tools for a flexible manufacturing system environment. All of these projects are working together to address information exchange, standardization, and information sharing to support rapid prototyping in a Flexible Manufacturing System (FMS) environment.

  11. Integrated Flexible Manufacturing Program for manufacturing automation and rapid prototyping

    SciTech Connect

    Brooks, S.L.; Brown, C.W.; King, M.S.; Simmons, W.R.; Zimmerman, J.J.

    1992-12-01

    The Kansas City Division of Allied Signal Inc., as part of the Integrated Flexible Manufacturing Program (IFMP), is developing an integrated manufacturing environment. Several systems are being developed to produce standards and automation tools for specific activities within the manufacturing environment. The Advanced Manufacturing Development System (AMDS) is concentrating on information standards (STEP) and product data transfer; the Expert Cut Planner system (XCUT) is concentrating on machining operation process planning standards and automation capabilities; the Advanced Numerical Control system (ANC) is concentrating on NC data preparation standards and NC data generation tools; the Inspection Planning and Programming Expert system (IPPEX) is concentrating on inspection process planning, coordinate measuring machine (CMM) inspection standards and CMM part program generation tools; and the Intelligent Scheduling and Planning System (ISAPS) is concentrating on planning and scheduling tools for a flexible manufacturing system environment. All of these projects are working together to address information exchange, standardization, and information sharing to support rapid prototyping in a Flexible Manufacturing System (FMS) environment.

  12. Pediatric Dispersible Tablets: a Modular Approach for Rapid Prototyping.

    PubMed

    Buck, Jonas; Huwyler, Jörg; Kühl, Peter; Dischinger, Angela

    2016-08-01

    The design of pediatric formulations is challenging. Solid dosage forms for children have to meet the needs of different ages, e.g. high number of dosing increments and strengths. A modular formulation strategy offering the possibility of rapid prototyping was applied. Different tablet compositions and the resulting tablet characteristics were investigated for dispersible tablets using customized analytical methods. Fluid bed granules were blended with extragranular components, and compressed to tablets. Disintegration behavior was studied with a Texture Analyzer and a Tensiometer. Methods for determination of disintegration time and water uptake of tablets were developed with a Texture Analyzer, and a Tensiometer, respectively. Twenty-two different tablet formulations were prepared and analyzed with respect to disintegration time, hardness, friability, and viscosity. Multivariate data analysis revealed a high impact of type and amount of viscosity enhancer on the disintegration behavior of tablets. An optimized formulation was selected with a disintegration time of 24 s. Methods providing additional information on the disintegration behavior of dispersible tablets compared to standard pharmacopoeia methods were established. Selecting the right type and level of viscosity enhancer and superdisintegrant was critical for developing pediatric tablets with a disintegration time of less than 30 s but still pleasant mouth feel.

  13. [Mandibular-driven simultaneous maxillo-mandibular distraction for hemifacial microsomia with rapid prototyping technology].

    PubMed

    Gao, Quan-Wen; Song, Hui-Feng; Xu, Ming-Huo; Liu, Chun-Ming; Chai, Jia-Ke

    2013-11-01

    To explore the clinical application of mandibular-driven simultaneous maxillo-mandihular distraction to correct hemifacial microsomia with rapid prototyping technology. The patient' s skull resin model was manufactured with rapid prototyping technology. The osteotomy was designed on skull resin model. According to the preoperative design, the patients underwent Le Fort I osteotomy and mandibular ramus osteotomy. The internal mandible distractor was embedded onto the osteotomy position. The occlusal titanium pin was implanted. Distraction were carried out by mandibular-driven simultaneous maxillo-mandihular distraction 5 days after operation. The distraction in five patients was complete as designed. No infection and dysosteogenesis happened. The longest distance of distraction was 28 mm, and the shortest distance was 16 mm. The facial asymmetry deformity was significantly improved at the end of distraction. The ocelusal plane of patients obviously improved. Rapid prototyping technology is helpful to design precisely osteotomy before operation. Mandibular-driven simultaneous maxillo-mandibular distraction can correct hemifacial microsomia. It is worth to clinical application.

  14. Using Rapid Prototyping to Design a Smoking Cessation Website with End-Users.

    PubMed

    Ronquillo, Charlene; Currie, Leanne; Rowsell, Derek; Phillips, J Craig

    2016-01-01

    Rapid prototyping is an iterative approach to design involving cycles of prototype building, review by end-users and refinement, and can be a valuable tool in user-centered website design. Informed by various user-centered approaches, we used rapid prototyping as a tool to collaborate with users in building a peer-support focused smoking-cessation website for gay men living with HIV. Rapid prototyping was effective in eliciting feedback on the needs of this group of potential end-users from a smoking cessation website.

  15. Rapid prototyping with lasers using metal powder jets

    NASA Astrophysics Data System (ADS)

    Liedl, Gerhard; Schuoecker, D.; Kny, E.

    2003-09-01

    Rapid Prototyping is an important part of modern development sequences, where a variety of solutions is available nowadays, ranging from ultrafast machining via casting technologies, laminated objects manufacturing, also with lasers, to stereolithography and laser sintering. Most of these processes suffer from certain restrictions, either in terms of raw material, geometry or quality of the finished workpiece. In particular, laser sintering leads to structures with a low density that reduces the strength of the part considerably. Since the individual powder particles are only molten at their surface and adhere thus to each other, only in small regions of the surface leaving the majority of the grain mass unmolten and resulting in a faint lattice that must be filled with an additional material to reach the necessary strength. A different solution offers the Blown Powder Process, where a jet of e.g. metal powder is directed towards the surface of the workpiece in the focus of a laser beam, thus melting each metal particle totally and producing practically molten droplets that settle on the momentary surface of the workpiece, thus being welded to the latter. Since all the material delivered to the workpiece is perfectly molten and resolidified, very dense structures with a high strength comparable to the strength of the initial unpowderized material are obtained, as experiments carried out by the authors with differed powderized materials have shown. It has also been demonstrated that the latter process can be used to generate nearly arbitrary 3D geometry. A lot of effort has been invested by the authors to avoid the influence of the direction of the necessary relative motion between laser, powder jet and workpiece and also to reduce the roughness of the surface generated by the actual process. Further experimental investigations will be devoted to the clarification of the range of materials, where the actual process can be applied and to the generation of practical

  16. Permeability of rapid prototyped artificial bone scaffold structures.

    PubMed

    Lipowiecki, Marcin; Ryvolová, Markéta; Töttösi, Ákos; Kolmer, Niels; Naher, Sumsun; Brennan, Stephen A; Vázquez, Mercedes; Brabazon, Dermot

    2014-11-01

    In this work, various three-dimensional (3D) scaffolds were produced via micro-stereolithography (µ-SLA) and 3D printing (3DP) techniques. This work demonstrates the advantages and disadvantages of these two different rapid prototyping methods for production of bone scaffolds. Compared to 3DP, SLA provides for smaller feature production with better dimensional resolution and accuracy. The permeability of these structures was evaluated experimentally and via numerical simulation utilizing a newly derived Kozeny-Carman based equation for intrinsic permeability. Both experimental and simulation studies took account of porosity percentage, pore size, and pore geometry. Porosity content was varied from 30% to 70%, pore size from 0.34 mm to 3 mm, and pore geometries of cubic and hexagonal closed packed were examined. Two different fluid viscosity levels of 1 mPa · s and 3.6 mPa · s were used. The experimental and theoretical results indicated that permeability increased when larger pore size, increased fluid viscosity, and higher percentage porosity were utilized, with highest to lowest degree of significance following the same order. Higher viscosity was found to result in permeabilities 2.2 to 3.3 times higher than for water. This latter result was found to be independent of pore morphology type. As well as demonstrating method for determining design parameters most beneficial for scaffold structure design, the results also illustrate how the variations in patient's blood viscosity can be extremely important in allowing for permeability through the bone and scaffold structures.

  17. Rapid optimization and prototyping for therapeutic antibody-like molecules

    PubMed Central

    Xu, Lihui; Kohli, Neeraj; Rennard, Rachel; Jiao, Yang; Razlog, Maja; Zhang, Kathy; Baum, Jason; Johnson, Bryan; Tang, Jian; Schoeberl, Birgit; Fitzgerald, Jonathan; Nielsen, Ulrik; Lugovskoy, Alexey A.

    2013-01-01

    Multispecific antibody-like molecules have the potential to advance the standard-of-care in many human diseases. The design of therapeutic molecules in this class, however, has proven to be difficult and, despite significant successes in preclinical research, only one trivalent antibody, catumaxomab, has demonstrated clinical utility. The challenge originates from the complexity of the design space where multiple parameters such as affinity, avidity, effector functions, and pharmaceutical properties need to be engineered in concurrent fashion to achieve the desired therapeutic efficacy. Here, we present a rapid prototyping approach that allows us to successfully optimize these parameters within one campaign cycle that includes modular design, yeast display of structure focused antibody libraries and high throughput biophysical profiling. We delineate this approach by presenting a design case study of MM-141, a tetravalent bispecific antibody targeting two compensatory signaling growth factor receptors: insulin-like growth factor 1 receptor (IGF-1R) and v-erb-b2 erythroblastic leukemia viral oncogene homolog 3 (ErbB3). A MM-141 proof-of-concept (POC) parent molecule did not meet initial design criteria due to modest bioactivity and poor stability properties. Using a combination of yeast display, structured-guided antibody design and library-scale thermal challenge assay, we discovered a diverse set of stable and active anti-IGF-1R and anti-ErbB3 single-chain variable fragments (scFvs). These optimized modules were reformatted to create a diverse set of full-length tetravalent bispecific antibodies. These re-engineered molecules achieved complete blockade of growth factor induced pro-survival signaling, were stable in serum, and had adequate activity and pharmaceutical properties for clinical development. We believe this approach can be readily applied to the optimization of other classes of bispecific or even multispecific antibody-like molecules. PMID:23392215

  18. An application generator for rapid prototyping of Ada real-time control software

    NASA Technical Reports Server (NTRS)

    Johnson, Jim; Biglari, Haik; Lehman, Larry

    1990-01-01

    The need to increase engineering productivity and decrease software life cycle costs in real-time system development establishes a motivation for a method of rapid prototyping. The design by iterative rapid prototyping technique is described. A tool which facilitates such a design methodology for the generation of embedded control software is described.

  19. Computer-aided design and manufacture and rapid prototyped polymethylmethacrylate reconstruction.

    PubMed

    Turgut, Gürsel; Özkaya, Özay; Kayali, Mahmut Ulvi

    2012-05-01

    This article discusses the application of computer-aided design and rapid prototyping techniques in polymethylmethacrylate reconstruction of craniofacial bone defects. This method avoids the probability of tissue damage due to exothermic reaction during the polymerization process and provides precise implants that exactly fit the defects. A total of 11 patients who have various-sized craniofacial defects underwent polymethylmethacrylate reconstruction. We performed three-dimensional reconstruction and operative design using computer software. According to the design, we determined the shape and size of the implants and made individualized implants for craniofacial bone defects with the rapid prototyping technique. With the application of computer-aided design and a rapid prototyping technique, we could accurately determine the shape, size, and embedding location. Prefabricating the individual implant models is useful in improving the accuracy of treatment. No cases of infection, seroma, extrusion, or contour irregularity occurred as a complication, and all patients were satisfied with the results. During the follow-up period, ranging from 1 to 6 years, all patients remained satisfied, and no complications were sustained. In cases of various-sized cranial defects and complex maxillofacial defects that have enough soft tissue coverage and that do not have contact with a third space, prefabricated methyl methacrylate implants can be used safely. Patients will feel more comfortable if the postoperative shape resembles the original appearance, so the proposed algorithm effectively creates a customized implant.

  20. Simulation of the Fissureless Technique for Thoracoscopic Segmentectomy Using Rapid Prototyping

    PubMed Central

    Nakada, Takeo; Inagaki, Takuya

    2014-01-01

    The fissureless lobectomy or anterior fissureless technique is a novel surgical technique, which avoids dissection of the lung parenchyma over the pulmonary artery during lobectomy by open thoracotomy approach or direct vision thoracoscopic surgery. This technique is indicated for fused lobes. We present two cases where thoracoscopic pulmonary segmentectomy was performed using the fissureless technique simulated by three-dimensional (3D) pulmonary models. The 3D model and rapid prototyping provided an accurate anatomical understanding of the operative field in both cases. We believe that the construction of these models is useful for thoracoscopic and other complicated surgeries of the chest. PMID:24633132

  1. Concept of using a benchmark part to evaluate rapid prototype processes

    NASA Technical Reports Server (NTRS)

    Cariapa, Vikram

    1994-01-01

    A conceptual benchmark part for guiding manufacturers and users of rapid prototyping technologies is proposed. This is based on a need to have some tool to evaluate the development of this technology and to assist the user in judiciously selecting a process. The benchmark part is designed to have unique product details and features. The extent to which a rapid prototyping process can reproduce these features becomes a measure of the capability of the process. Since rapid prototyping is a dynamic technology, this benchmark part should be used to continuously monitor process capability of existing and developing technologies. Development of this benchmark part is, therefore, based on an understanding of the properties required from prototypes and characteristics of various rapid prototyping processes and measuring equipment that is used for evaluation.

  2. JTEC/WTEC panel report on rapid prototyping in Europe and Japan. Volume 1: Analytical chapters

    SciTech Connect

    Prinz, F.B.; Atwood, C.L.; Aubin, R.F.

    1997-03-01

    Mastering the art of rapidly prototyping parts and products is vital for any corporation in the race to launch new products. During the last decade, new methods and tools have emerged to facilitate and accelerate product creation. Physical prototyping, in particular, has gained popularity with the help of a concept called layered manufacturing or solid free form fabrication (SFF). The US pioneered development and commercialization of layered manufacturing systems; now, significant efforts in this area are underway in Europe and Japan, spurred by the obvious advantages of layered manufacturing`s ability to rapidly create physical models regardless of shape complexity. A major research focus is direct manufacture of objects from materials such as metals, ceramics, and plastics that have properties similar to their traditionally manufactured counterparts. In addition, layered manufacturing appears to have the potential to build objects with shape complexity and material variety that previously have been impossible. In 1995 the US government, encouraged by the Rapid Prototyping Association of the Society of Manufacturing Engineers (SME), initiated a study administered by the Japanese Technology Evaluation Center/World Technology Evaluation Center (JTEC/WTEC) to assess the capabilities of selected European countries and Japan in developing and implementing layered manufacturing technologies. The approach to this study was three-pronged: first, identify and study key foreign RP technologies and discover important new applications under development; second, evaluate and compare foreign competencies to those in the US; and third, critically examine related standards. Following are the major conclusions of JTEC/WTEC`s panel of experts concerning the current status of rapid prototyping in Europe and Japan compared to the US: (1) the US is ahead in technical innovations, materials, and manufacturing applications of layered manufacturing technology; (2) in the area of machine

  3. Rapid prototyping of electrochemical lateral flow devices: stencilled electrodes.

    PubMed

    Aller Pellitero, Miguel; Kitsara, Maria; Eibensteiner, Friedrich; del Campo, F Javier

    2016-04-21

    A straightforward and very cost effective method is proposed to prototype electrodes using pressure sensitive adhesives (PSA) and a simple cutting technique. Two cutting methods, namely blade cutting and CO2 laser ablation, are compared and their respective merits are discussed. The proposed method consists of turning the protective liner on the adhesive into a stencil to apply screen-printing pastes. After the electrodes have been printed, the liner is removed and the PSA can be used as a backing material for standard lateral flow membranes. We present the fabrication of band electrodes down to 250 μm wide, and their characterization using microscopy techniques and cyclic voltammetry. The prototyping approach presented here facilitates the development of new electrochemical devices even if very limited fabrication resources are available. Here we demonstrate the fabrication of a simple lateral-flow device capable of determining glucose in blood. The prototyping approach presented here is highly suitable for the development of novel electroanalytical tools.

  4. On the Application of Rapid Prototyping Technology for the Fabrication of Flapping Wings for Micro Air Vehicles

    NASA Astrophysics Data System (ADS)

    Kraemer, Kurtis Leigh

    Micro air vehicles (MAV) are a class of small uninhabited aircraft with dimensions less than 15 cm (6 in) and mass less than 500g (1.1 lbs). The aim of this research was to develop a fast, accurate, low-cost, and repeatable fabrication process for flapping MAV wings. Through the use of the RepRap Mendel open-source fused-deposition modeling (FDM) rapid prototyping machine ("3-D printer"), various wing prototypes were designed and fabricated using a bio-inspired approach. Testing of the aerodynamic performance of both real locust wings and the 3-D printed wing prototypes was performed through axial spin testing. Bending stiffness measurements were also performed on the 3-D printed wings. Through the use of open-source rapid prototyping technology, a fast and low-cost fabrication process for flapping MAV wings has been developed, out of which further understanding of flapping wing design and fabrication has been gained.

  5. A pilot biomedical engineering course in rapid prototyping for mobile health.

    PubMed

    Stokes, Todd H; Venugopalan, Janani; Hubbard, Elena N; Wang, May D

    2013-01-01

    Rapid prototyping of medically assistive mobile devices promises to fuel innovation and provides opportunity for hands-on engineering training in biomedical engineering curricula. This paper presents the design and outcomes of a course offered during a 16-week semester in Fall 2011 with 11 students enrolled. The syllabus covered a mobile health design process from end-to-end, including storyboarding, non-functional prototypes, integrated circuit programming, 3D modeling, 3D printing, cloud computing database programming, and developing patient engagement through animated videos describing the benefits of a new device. Most technologies presented in this class are open source and thus provide unlimited "hackability". They are also cost-effective and easily transferrable to other departments.

  6. Applications of stereolithography for rapid prototyping of biologically compatible chip-based physiometers

    NASA Astrophysics Data System (ADS)

    Fuad, Nurul Mohd; Zhu, Feng; Kaslin, Jan; Wlodkowic, Donald

    2016-12-01

    Despite the growing demand and numerous applications for the biomedical community, the developments in millifluidic devices for small model organisms are limited compared to other fields of biomicrofluidics. The main reasons for this stagnanation are difficulties in prototyping of millimeter scale and high aspect ratio devices needed for large metazoan organisms. Standard photolithography is in this context a time consuming procedure not easily adapted for fabrication of molds with vertical dimensions above 1 mm. Moreover, photolithography is still largely unattainable to a gross majority of biomedical laboratories willing to pursue custom development of their own chip-based platforms due to costs and need for dedicated clean room facilities. In this work, we present application of high-definition additive manufacturing systems for fabrication of 3D printed moulds used in soft lithography. Combination of 3D printing with PDMS replica molding appears to be an alternative for millifluidic systems that yields rapid and cost effective prototyping pipeline. We investigated the important aspects on both 3D printed moulds and PDMS replicas such as geometric accuracies and surface topology. Our results demonstrated that SLA technologies could be applied for rapid and accurate fabrication of millifluidic devices for trapping of millimetre-sized specimens such as living zebrafish larvae. We applied the new manufacturing method in a proof-of-concept prototype device capable of trapping and immobilizing living zebrafish larvae for recording heart rate variation in cardio-toxicity experiments.

  7. Design and fabrication of custom mandible titanium tray based on rapid prototyping.

    PubMed

    Singare, Sekou; Dichen, Li; Bingheng, Lu; Yanpu, Liu; Zhenyu, Gong; Yaxiong, Liu

    2004-10-01

    During the past few years, the combination of medical imaging and rapid manufacturing technique has proven to be a very important development. On the other hand, the conventional method has some drawbacks. For example, it takes longer time to complete an operation and it also presents some difficulty in matching the repaired contours. With advanced software and hardware, an image of an undamaged bone similar to that of the patient can be made from computerised tomography (CT); and a physical object constructed by the mirror-processed image data can be quickly fabricated with a high degree of fitting with the patient's bone. This paper presents a methodology for the design and fabrication of an individual titanium tray for the repair of mandible defects. Methods for the tray modeling using CAD system are presented: A 3D model of the bony defect is generated after the acquisition of helical CT data. An individual tray is designed using freeform surfaces geometries and fabricated by rapid prototyping (RP) technology. The results of tray filling with bone-grafting materials are then presented. the tray is inserted into the patient mandible segment. The symmetry and reconstruction quality contour of the repaired mandible was satisfactory. Thus, the patient is able to eat normally. The bone-grafting material harvested from the anterior ilium was low. The clinical experience showed that rapid prototyping and reverse engineering software are effective methods of fabricating custom trays for mandibular reconstruction after bone loss due to a tumor.

  8. Rapid Prototyping Technologies and their Applications in Prosthodontics, a Review of Literature.

    PubMed

    Torabi, Kianoosh; Farjood, Ehsan; Hamedani, Shahram

    2015-03-01

    The early computer-aided design/computer-aided manufacturing (CAD/CAM) systems were relied exclusively on subtractive methods. In recent years, additive methods by employing rapid prototyping (RP) have progressed rapidly in various fields of dentistry as they have the potential to overcome known drawbacks of subtractive techniques such as fit problems. RP techniques have been exploited to build complex 3D models in medicine since the 1990s. RP has recently proposed successful applications in various dental fields, such as fabrication of implant surgical guides, frameworks for fixed and removable partial dentures, wax patterns for the dental prosthesis, zirconia prosthesis and molds for metal castings, and maxillofacial prosthesis and finally, complete dentures. This paper aimed to offer a comprehensive literature review of various RP methods, particularly in dentistry, that are expected to bring many improvements to the field. A search was made through MEDLINE database and Google scholar search engine. The keywords; 'rapid prototyping' and 'dentistry' were searched in title/abstract of publications; limited to 2003 to 2013, concerning past decade. The inclusion criterion was the technical researches that predominately included laboratory procedures. The exclusion criterion was meticulous clinical and excessive technical procedures. A total of 106 articles were retrieved, recited by authors and only 50 met the specified inclusion criteria for this review. Selected articles had used rapid prototyping techniques in various fields in dentistry through different techniques. This review depicted the different laboratory procedures employed in this method and confirmed that RP technique have been substantially feasible in dentistry. With advancement in various RP systems, it is possible to benefit from this technique in different dental practices, particularly in implementing dental prostheses for different applications.

  9. [Fabricating facial prostheses using CAD/CAM and rapid prototyping technique].

    PubMed

    Huang, Xuemei; Jiao, Ting; Lin, Yanping; Zhang, Wenqiang; Wang, Chengtao; Zhang, Fuqiang

    2005-04-01

    At present, the treatments of hemifacial microsomia such as the missing of ear and eye still rely on the skill of technician to make the wax model of contralateral apparatus of patient in China. In this paper, CAD/CAM and rapid prototyping (RP) techniques are integrated to successfully create a silastic prosthesis by using the patient's data of CT or laser scanning. The clinical results suggest that a high accuracy has been achieved in shape, size, and protrusion of the facial prostheses, which indicates that the application of RP techniques in conjunction with CAD/CAM is a suitable approach for fabricating facial prosthesis.

  10. Characterization of 3D rapid prototyped polymeric material by ultrasonic methods

    NASA Astrophysics Data System (ADS)

    Livings, Richard; Dayal, Vinay; Barnard, Dan

    2015-03-01

    Rapid prototyped parts are quickly becoming a viable alternative for manufacturers. Although the polymeric material is initially isotropic, the printing process introduces a level of anisotropy. This work characterizes the elastic and acoustic properties of the material, after printing, using ultrasonic methods. The elastic constants and the level of anisotropy are determined by measuring the ultrasonic wave velocities. It is shown that the material possesses less symmetry than the orthotropic material model. The dispersion and attenuation characteristics are also determined to provide a basis for ultrasonic flaw detection.

  11. Rapid prototyping of polymer-based MEMS devices using UV YAG laser

    NASA Astrophysics Data System (ADS)

    Yung, K. C.; Mei, S. M.; Yue, T. M.

    2004-12-01

    This paper deals with the laser micro processing technology in the fabrication of micro-electro-mechanical system (MEMS) device. A polymer-based capacitive micro accelerometer is designed and modeled in this paper, and is fabricated with laser micromachining and micro patterning technologies. The fabricated micro accelerometer is finally experimentally verified by measuring the shock of a dropping hammer. It is demonstrated that pulsed UV laser micro processing technology provides a quite suitable fabrication method for polymer-based MEMS rapid prototyping and small volume production.

  12. Novel Applications of Rapid Prototyping in Gamma-ray and X-ray Imaging

    PubMed Central

    Miller, Brian W.; Moore, Jared W.; Gehm, Michael E.; Furenlid, Lars R.; Barrett, Harrison H.

    2010-01-01

    Advances in 3D rapid-prototyping printers, 3D modeling software, and casting techniques allow for the fabrication of cost-effective, custom components in gamma-ray and x-ray imaging systems. Applications extend to new fabrication methods for custom collimators, pinholes, calibration and resolution phantoms, mounting and shielding components, and imaging apertures. Details of the fabrication process for these components are presented, specifically the 3D printing process, cold casting with a tungsten epoxy, and lost-wax casting in platinum. PMID:22984341

  13. CAD - CAM Procedures Used for Rapid Prototyping of Prosthetic Hip Joint Bone

    NASA Astrophysics Data System (ADS)

    Popa, Luminita I.; Popa, Vasile N.

    2016-11-01

    The article addresses the issue of rapid prototyping CAD/ CAM procedures, based on CT imaging, for custom implants dedicated to hip arthroplasty and the correlation study to be achieved between femoral canal shape, valued by modern imaging methods, and the prosthesis form. A set of CT images is transformed into a digital model using one of several software packages available for conversion. The purpose of research is to obtain prosthesis with compatible characteristics as close to the physiological, with an optimal adjustment of the prosthesis to the bone in which it is implanted, allowing the recovery of the patient physically, mentally and socially.

  14. Modeling rapidly rotating stars

    NASA Astrophysics Data System (ADS)

    Rieutord, M.

    2006-06-01

    We review the quest of modeling rapidly rotating stars during the past 40 years and detail the challenges to be taken up by models facing new data from interferometry, seismology, spectroscopy... We then present the progress of the ESTER project aimed at giving a physically self-consistent model for the structure and evolution of rapidly rotating stars.

  15. Reconceiving ISD: Three Perspectives on Rapid Prototyping as a Paradigm Shift.

    ERIC Educational Resources Information Center

    Rathbun, Gail A.; And Others

    Confronting recent design challenges, instructional designers have latched onto adaptive procedural techniques from outside the Instructional Systems Design (ISD) field. This discussion of rapid prototyping (RP) examines the perspectives of: (1) the prototype as the designer"s cognitive tool; (2) the designer as co-inquirer; and (3) the…

  16. Product Development and its Comparative Analysis by SLA, SLS and FDM Rapid Prototyping Processes

    NASA Astrophysics Data System (ADS)

    Choudhari, C. M.; Patil, V. D.

    2016-09-01

    To grab market and meeting deadlines has increased the scope of new methods in product design and development. Industries continuously strive to optimize the development cycles with high quality and cost efficient products to maintain market competitiveness. Thus the need of Rapid Prototyping Techniques (RPT) has started to play pivotal role in rapid product development cycle for complex product. Dimensional accuracy and surface finish are the corner stone of Rapid Prototyping (RP) especially if they are used for mould development. The paper deals with the development of part made with the help of Selective Laser Sintering (SLS), Stereo-lithography (SLA) and Fused Deposition Modelling (FDM) processes to benchmark and investigate on various parameters like material shrinkage rate, dimensional accuracy, time, cost and surface finish. This helps to conclude which processes can be proved to be effective and efficient in mould development. In this research work the emphasis was also given to the design stage of a product development to obtain an optimum design solution for an existing product.

  17. [Reverse engineering and rapid prototyping technique for restoration of mandibular bone defect].

    PubMed

    Yang, Juncheng; Zheng, Guangyong

    2009-04-01

    The application principle and procedure of reverse engineering and rapid prototyping techniques are introduced in this paper. The description is concentrated on the applications of the above techniques in medical field, especially in reconstructive surgery of mandibular bone defect.

  18. [The application of the reverse engineering and rapid prototyping technology in the design of respiratory masks].

    PubMed

    Hu, Ming-xi; Gao, Wang-yu; Du, Zheng-jie; Zhang, Yan-jun

    2006-05-01

    The application of the reverse engineering and rapid prototyping technologies in the design of respiratory masks is introduced in this paper. Practice indicates that the technologies can reduce the cost and save the time in product developments.

  19. Weapon identification using antemortem computed tomography with virtual 3D and rapid prototype modeling--a report in a case of blunt force head injury.

    PubMed

    Woźniak, Krzysztof; Rzepecka-Woźniak, Ewa; Moskała, Artur; Pohl, Jerzy; Latacz, Katarzyna; Dybała, Bogdan

    2012-10-10

    A frequent request of a prosecutor referring to forensic autopsy is to determine the mechanism of an injury and to identify the weapons used to cause those injuries. This task could be problematic in many ways, including changes in the primary injury caused by medical intervention and the process of healing. To accomplish this task, the forensic pathologist has to gather all possible information during the post-mortem examination. The more data is collected, the easier it is to obtain an accurate answer to the prosecutor's question. The authors present a case of head injuries that the victim sustained under unknown circumstances. The patient underwent neurosurgical treatment which resulted in alteration of the bone fracture pattern. The only way to evaluate this injury was to analyze antemortem clinical data, especially CT scans, with virtual 3D reconstruction of the fractured skull. A physical model of a part of the broken skull was created with the use of 3D printing. These advanced techniques, applied for the first time in Poland for forensic purposes, allowed investigators to extract enough data to develop a hypothesis about the mechanism of injury and the weapon most likely used. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  20. Rapid Prototyping as Method for Developing Instructional Strategies for Supporting Computer-Mediated Communication among University Students

    ERIC Educational Resources Information Center

    Knowlton, Dave S.

    2006-01-01

    Because rapid prototyping results in the quick development of curriculum, materials, and processes, it is a form of design that could be particularly useful to professors in higher education. Yet, literature documenting the use of rapid prototyping in higher education is scarce. This paper offers a case example of rapid prototyping being used as a…

  1. [Application status of rapid prototyping technology in artificial bone based on reverse engineering].

    PubMed

    Fang, Ao; Zheng, Min; Fan, Ding

    2015-02-01

    Artificial bone replacement has made an important contribution to safeguard human health and improve the quality of life. The application requirements of rapid prototyping technology based on reverse engineering in individualized artificial bone with individual differences are particularly urgent. This paper reviewed the current research and applications of rapid prototyping and reverse engineering in artificial bone. The research developments and the outlook of bone kinematics and dynamics simulation are also introduced.

  2. Rapid Prototyping of Simulated VIIRS Data in the SERVIR Fire Rapid Response System

    NASA Astrophysics Data System (ADS)

    Easson, G.; Kuszmaul, J. S.; Yarbrough, L. D.; Irwin, D.; Cherrington, E.

    2006-12-01

    A rapid prototyping capability experiment has been established involving the application of the SERVIR (Sistema Regional de Visualización y Monitoreo) decision support tool, which is NASA's and its partner agencies' tool to monitor groundcover and climatic conditions in Mesoamerica. As an information system, the SERVIR tool processes data products from multiple sources and the outcome is visualized through interactive digital maps, standard view map outputs or 3D real-time visualization. The focus of this research is one of the SERVIR Fire Rapid Response products known as the MODIS SERVIR Fire Extent Product, which was developed to meet the requirements of the Guatemalan Park Service. The credibility of SERVIR's monitoring tools currently depends upon NASA's MODIS data, which is nearing the end of its availability. This will make it necessary to transition to the planned replacement sensor, VIIRS. The impact of this transition on the performance of SERVIR's fire detection tools is the current focus of our investigation. A quantitative assessment of fire conditions in Guatemala is made using MODIS data and is compared to the anticipated performance using simulated data that would have been produced by a VIIRS-like sensor. Using a low-density geospatial database, the comparison is made for a number of dates from the 2003 Guatemalan fire season, where ground validation data is available. A comparative assessment is also made using the kappa statistic applied to the land classifications resulting from both the MODIS- and VIIRS- based fire detection algorithms.

  3. Use of rapid prototyping drill template for the expansive open door laminoplasty: A cadaveric study.

    PubMed

    Rong, Xin; Wang, Beiyu; Chen, Hua; Ding, Chen; Deng, Yuxiao; Ma, Lipeng; Ma, Yanzhao; Liu, Hao

    2016-11-01

    Trough preparation is a technically demanding yet critical procedure for successful expansive open door laminoplasty (EOLP), requiring both proper position and appropriate bone removal. We aimed to use the specific rapid prototyping drill template to achieve such requirement. The 3D model of the cadaveric cervical spine was reconstructed using the Mimics 17.0 and Geomagic Studio 12.0 software. The drilling template was designed in the 3-Matic software. The trough position was simulated at the medial margin of the facet joint. Two holders were designed on both sides. On the open side, the holder would just allow the drill penetrate the ventral cortex of the lamina. On the hinge side, the holder was designed to keep the ventral cortex of the lamina intact. One orthopedic resident performed the surgery using the rapid prototyping drill template on four cadavers (template group). A control group of four cadavers were operated upon without the use of the template. The deviation of the final trough position from the simulated trough position was 0.18mm±0.51mm in the template group. All the troughs in the template group and 40% of the troughs in the control group were at the medial side of the facet joint. The complete hinge fracture rate was 5% in the template group, significantly lower than that (55%) in the control group (P=0.01). The rapid prototyping drill template could help the surgeon accomplish proper trough position and appropriate bone removal in EOLP on the cadaveric cervical spine. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Rapid prototyping compliant arterial phantoms for in-vitro studies and device testing

    PubMed Central

    2013-01-01

    Background Compliant vascular phantoms are desirable for in-vitro patient-specific experiments and device testing. TangoPlus FullCure 930® is a commercially available rubber-like material that can be used for PolyJet rapid prototyping. This work aims to gather preliminary data on the distensibility of this material, in order to assess the feasibility of its use in the context of experimental cardiovascular modelling. Methods The descending aorta anatomy of a volunteer was modelled in 3D from cardiovascular magnetic resonance (CMR) images and rapid prototyped using TangoPlus. The model was printed with a range of increasing wall thicknesses (0.6, 0.7, 0.8, 1.0 and 1.5 mm), keeping the lumen of the vessel constant. Models were also printed in both vertical and horizontal orientations, thus resulting in a total of ten specimens. Compliance tests were performed by monitoring pressure variations while gradually increasing and decreasing internal volume. Knowledge of distensibility was thus derived and then implemented with CMR data to test two applications. Firstly, a patient-specific compliant model of hypoplastic aorta suitable for connection in a mock circulatory loop for in-vitro tests was manufactured. Secondly, the right ventricular outflow tract (RVOT) of a patient necessitating pulmonary valve replacement was printed in order to physically test device insertion and assess patient’s suitability for percutaneous pulmonary valve intervention. Results The distensibility of the material was identified in a range from 6.5 × 10-3 mmHg-1 for the 0.6 mm case, to 3.0 × 10-3 mmHg-1 for the 1.5 mm case. The models printed in the vertical orientation were always more compliant than their horizontal counterpart. Rapid prototyping of a compliant hypoplastic aorta and of a RVOT anatomical model were both feasible. Device insertion in the RVOT model was successful. Conclusion Values of distensibility, compared with literature data, show that TangoPlus is suitable for

  5. Deposition, patterning, and utility of conductive materials for the rapid prototyping of chemical and bioanalytical devices.

    PubMed

    Gabardo, C M; Soleymani, L

    2016-06-21

    Rapid prototyping is a critical step in the product development cycle of miniaturized chemical and bioanalytical devices, often categorized as lab-on-a-chip devices, biosensors, and micro-total analysis systems. While high throughput manufacturing methods are often preferred for large-volume production, rapid prototyping is necessary for demonstrating and predicting the performance of a device and performing field testing and validation before translating a product from research and development to large volume production. Choosing a specific rapid prototyping method involves considering device design requirements in terms of minimum feature sizes, mechanical stability, thermal and chemical resistance, and optical and electrical properties. A rapid prototyping method is then selected by making engineering trade-off decisions between the suitability of the method in meeting the design specifications and manufacturing metrics such as speed, cost, precision, and potential for scale up. In this review article, we review four categories of rapid prototyping methods that are applicable to developing miniaturized bioanalytical devices, single step, mask and deposit, mask and etch, and mask-free assembly, and we will focus on the trade-offs that need to be made when selecting a particular rapid prototyping method. The focus of the review article will be on the development of systems having a specific arrangement of conductive or semiconductive materials.

  6. Rapid prototyping technique in the preoperative planning for total hip arthroplasty with custom femoral components.

    PubMed

    Faur, Cosmin; Crainic, Nicolae; Sticlaru, Carmen; Oancea, Cristian

    2013-03-01

    One of the problems we come across in our practice is related to the patients with very disturbed anatomy structures of the hip joint due to the incompatibilities between standard implants and host bone. These incompatibilities are usually represented by an extreme narrowing of the femoral medullary canal or sometimes by disturbances of the diaphyseal anatomical axis of the femur and are encountered in younger patients who usually require pressfit uncemented implants in order to achieve a normal survivorship of the implant. In these particular cases, customized prosthetic components may represent an alternative, but there are still controversies regarding the biomechanical behavior of these implants compared to the standard components.The use of prototypes for the receiving bone and for the prosthetic implant, respectively, is helpful in the validation process of the optimal model of custom implant by eliminating those designs that cannot be inserted into the medullar canal or those that could injure the receiving bone structure.Prototype design and execution for both the implant and femoral structure by means of rapid prototyping technology represents a major advantage in carrying out the preoperative planning of this type of surgical interventions due to the possibility of preoperative simulation of the insertion of femoral component into the medullar canal.

  7. Rapid prototyping of compliant human aortic roots for assessment of valved stents.

    PubMed

    Kalejs, Martins; von Segesser, Ludwig Karl

    2009-02-01

    Adequate in-vitro training in valved stents deployment as well as testing of the latter devices requires compliant real-size models of the human aortic root. The casting methods utilized up to now are multi-step, time consuming and complicated. We pursued a goal of building a flexible 3D model in a single-step procedure. We created a precise 3D CAD model of a human aortic root using previously published anatomical and geometrical data and printed it using a novel rapid prototyping system developed by the Fab@Home project. As a material for 3D fabrication we used common house-hold silicone and afterwards dip-coated several models with dispersion silicone one or two times. To assess the production precision we compared the size of the final product with the CAD model. Compliance of the models was measured and compared with native porcine aortic root. Total fabrication time was 3 h and 20 min. Dip-coating one or two times with dispersion silicone if applied took one or two extra days, respectively. The error in dimensions of non-coated aortic root model compared to the CAD design was <3.0% along X, Y-axes and 4.1% along Z-axis. Compliance of a non-coated model as judged by the changes of radius values in the radial direction by 16.39% is significantly different (P<0.001) from native aortic tissue--23.54% at the pressure of 80-100 mmHg. Rapid prototyping of compliant, life-size anatomical models with the Fab@Home 3D printer is feasible--it is very quick compared to previous casting methods.

  8. The development of an autonomous rendezvous and docking simulation using rapid integration and prototyping technology

    NASA Technical Reports Server (NTRS)

    Shackelford, John H.; Saugen, John D.; Wurst, Michael J.; Adler, James

    1991-01-01

    A generic planar 3 degree of freedom simulation was developed that supports hardware in the loop simulations, guidance and control analysis, and can directly generate flight software. This simulation was developed in a small amount of time utilizing rapid prototyping techniques. The approach taken to develop this simulation tool, the benefits seen using this approach to development, and on-going efforts to improve and extend this capability are described. The simulation is composed of 3 major elements: (1) Docker dynamics model, (2) Dockee dynamics model, and (3) Docker Control System. The docker and dockee models are based on simple planar orbital dynamics equations using a spherical earth gravity model. The docker control system is based on a phase plane approach to error correction.

  9. The development of an autonomous rendezvous and docking simulation using rapid integration and prototyping technology

    NASA Astrophysics Data System (ADS)

    Shackelford, John H.; Saugen, John D.; Wurst, Michael J.; Adler, James

    A generic planar 3 degree of freedom simulation was developed that supports hardware in the loop simulations, guidance and control analysis, and can directly generate flight software. This simulation was developed in a small amount of time utilizing rapid prototyping techniques. The approach taken to develop this simulation tool, the benefits seen using this approach to development, and on-going efforts to improve and extend this capability are described. The simulation is composed of 3 major elements: (1) Docker dynamics model, (2) Dockee dynamics model, and (3) Docker Control System. The docker and dockee models are based on simple planar orbital dynamics equations using a spherical earth gravity model. The docker control system is based on a phase plane approach to error correction.

  10. A novel 3D template for mandible and maxilla reconstruction: Rapid prototyping using stereolithography

    PubMed Central

    Kumta, Samir; Kumta, Monica; Jain, Leena; Purohit, Shrirang; Ummul, Rani

    2015-01-01

    Introduction: Replication of the exact three-dimensional (3D) structure of the maxilla and mandible is now a priority whilst attempting reconstruction of these bones to attain a complete functional and aesthetic rehabilitation. We hereby present the process of rapid prototyping using stereolithography to produce templates for modelling bone grafts and implants for maxilla/mandible reconstructions, its applications in tumour/trauma, and outcomes for primary and secondary reconstruction. Materials and Methods: Stereolithographic template-assisted reconstruction was used on 11 patients for the reconstruction of the mandible/maxilla primarily following tumour excision and secondarily for the realignment of post-traumatic malunited fractures or deformity corrections. Data obtained from the computed tomography (CT) scans with 1-mm resolution were converted into a computer-aided design (CAD) using the CT Digital Imaging and Communications in Medicine (DICOM) data. Once a CAD model was constructed, it was converted into a stereolithographic format and then processed by the rapid prototyping technology to produce the physical anatomical model using a resin. This resin model replicates the native mandible, which can be thus used off table as a guide for modelling the bone grafts. Discussion: This conversion of two-dimensional (2D) data from CT scan into 3D models is a very precise guide to shaping the bone grafts. Further, this CAD can reconstruct the defective half of the mandible using the mirror image principle, and the normal anatomical model can be created to aid secondary reconstructions. Conclusion: This novel approach allows a precise translation of the treatment plan directly to the surgical field. It is also an important teaching tool for implant moulding and fixation, and helps in patient counselling. PMID:26933279

  11. A novel 3D template for mandible and maxilla reconstruction: Rapid prototyping using stereolithography.

    PubMed

    Kumta, Samir; Kumta, Monica; Jain, Leena; Purohit, Shrirang; Ummul, Rani

    2015-01-01

    Replication of the exact three-dimensional (3D) structure of the maxilla and mandible is now a priority whilst attempting reconstruction of these bones to attain a complete functional and aesthetic rehabilitation. We hereby present the process of rapid prototyping using stereolithography to produce templates for modelling bone grafts and implants for maxilla/mandible reconstructions, its applications in tumour/trauma, and outcomes for primary and secondary reconstruction. Stereolithographic template-assisted reconstruction was used on 11 patients for the reconstruction of the mandible/maxilla primarily following tumour excision and secondarily for the realignment of post-traumatic malunited fractures or deformity corrections. Data obtained from the computed tomography (CT) scans with 1-mm resolution were converted into a computer-aided design (CAD) using the CT Digital Imaging and Communications in Medicine (DICOM) data. Once a CAD model was constructed, it was converted into a stereolithographic format and then processed by the rapid prototyping technology to produce the physical anatomical model using a resin. This resin model replicates the native mandible, which can be thus used off table as a guide for modelling the bone grafts. This conversion of two-dimensional (2D) data from CT scan into 3D models is a very precise guide to shaping the bone grafts. Further, this CAD can reconstruct the defective half of the mandible using the mirror image principle, and the normal anatomical model can be created to aid secondary reconstructions. This novel approach allows a precise translation of the treatment plan directly to the surgical field. It is also an important teaching tool for implant moulding and fixation, and helps in patient counselling.

  12. Prototyping of cerebral vasculature physical models.

    PubMed

    Khan, Imad S; Kelly, Patrick D; Singer, Robert J

    2014-01-01

    Prototyping of cerebral vasculature models through stereolithographic methods have the ability to accurately depict the 3D structures of complicated aneurysms with high accuracy. We describe the method to manufacture such a model and review some of its uses in the context of treatment planning, research, and surgical training. We prospectively used the data from the rotational angiography of a 40-year-old female who presented with an unruptured right paraclinoid aneurysm. The 3D virtual model was then converted to a physical life-sized model. The model constructed was shown to be a very accurate depiction of the aneurysm and its associated vasculature. It was found to be useful, among other things, for surgical training and as a patient education tool. With improving and more widespread printing options, these models have the potential to become an important part of research and training modalities.

  13. Rapid Prototyping Technologies and their Applications in Prosthodontics, a Review of Literature

    PubMed Central

    Torabi, Kianoosh; Farjood, Ehsan; Hamedani, Shahram

    2015-01-01

    The early computer-aided design/computer-aided manufacturing (CAD/CAM) systems were relied exclusively on subtractive methods. In recent years, additive methods by employing rapid prototyping (RP) have progressed rapidly in various fields of dentistry as they have the potential to overcome known drawbacks of subtractive techniques such as fit problems. RP techniques have been exploited to build complex 3D models in medicine since the 1990s. RP has recently proposed successful applications in various dental fields, such as fabrication of implant surgical guides, frameworks for fixed and removable partial dentures, wax patterns for the dental prosthesis, zirconia prosthesis and molds for metal castings, and maxillofacial prosthesis and finally, complete dentures. This paper aimed to offer a comprehensive literature review of various RP methods, particularly in dentistry, that are expected to bring many improvements to the field. A search was made through MEDLINE database and Google scholar search engine. The keywords; ‘rapid prototyping’ and ‘dentistry’ were searched in title/abstract of publications; limited to 2003 to 2013, concerning past decade. The inclusion criterion was the technical researches that predominately included laboratory procedures. The exclusion criterion was meticulous clinical and excessive technical procedures. A total of 106 articles were retrieved, recited by authors and only 50 met the specified inclusion criteria for this review. Selected articles had used rapid prototyping techniques in various fields in dentistry through different techniques. This review depicted the different laboratory procedures employed in this method and confirmed that RP technique have been substantially feasible in dentistry. With advancement in various RP systems, it is possible to benefit from this technique in different dental practices, particularly in implementing dental prostheses for different applications. PMID:25759851

  14. Rapid prototyping of multiphase microfluidics with robotic cutters

    NASA Astrophysics Data System (ADS)

    Li, Zidong; Zhao, Zhengtuo; Lo, Joe Fu-jiou

    2014-03-01

    Microfluidic devices offer novel techniques to address biological and biomedical issues. Standard microfluidic fabrication uses photolithography to pattern channels on silicon wafers with high resolution. Even the relatively straightforward SU8 and soft lithography in microfluidics require investing and training in photolithography, which is also time consuming due to complicated thick resist procedures, including sensitive substrate pretreatment, coating, soft bake, expose, post-exposure bake, and developing steps. However, for applications where low resolution (>200 μm) and high turn-around (> 4 designs/day) prototyping are met with little or no lithography infrastructure, robotic cutters [1] offer flexible options for making glass and PDMS microfluidics. We describe the use of robotics cutters for designing microfluidic geometries, and compliment it with safe glass etching, with depths down to 60 μm. Soft lithography patterning of 200 μm thick PDMS membrane was also explored. Without high equipment investment and lengthy student training, both glass and PDMS microfluidics can be achieved in small facilities using this technique.

  15. A Method to Represent Heterogeneous Materials for Rapid Prototyping: The Matryoshka Approach.

    PubMed

    Lei, Shuangyan; Frank, Matthew C; Anderson, Donald D; Brown, Thomas D

    The purpose of this paper is to present a new method for representing heterogeneous materials using nested STL shells, based, in particular, on the density distributions of human bones. Nested STL shells, called Matryoshka models, are described, based on their namesake Russian nesting dolls. In this approach, polygonal models, such as STL shells, are "stacked" inside one another to represent different material regions. The Matryoshka model addresses the challenge of representing different densities and different types of bone when reverse engineering from medical images. The Matryoshka model is generated via an iterative process of thresholding the Hounsfield Unit (HU) data using computed tomography (CT), thereby delineating regions of progressively increasing bone density. These nested shells can represent regions starting with the medullary (bone marrow) canal, up through and including the outer surface of the bone. The Matryoshka approach introduced can be used to generate accurate models of heterogeneous materials in an automated fashion, avoiding the challenge of hand-creating an assembly model for input to multi-material additive or subtractive manufacturing. This paper presents a new method for describing heterogeneous materials: in this case, the density distribution in a human bone. The authors show how the Matryoshka model can be used to plan harvesting locations for creating custom rapid allograft bone implants from donor bone. An implementation of a proposed harvesting method is demonstrated, followed by a case study using subtractive rapid prototyping to harvest a bone implant from a human tibia surrogate.

  16. RETRACTED: Auricular prosthesis fabrication using computer-aided design and rapid prototyping technologies.

    PubMed

    Shah, Mayank

    2016-06-01

    At the request of the editorMayank Shah 'Auricular prosthesis fabrication using computer-aided design and rapid prototyping technologies' Prosthetics and Orthotics International, published online before print on October 8, 2013 as doi:10.1177/0309364613504779has been retracted. This is because it contains unattributed overlap withK. Subburaj, C. Nair, S. Rajesh, S. M. Meshram, B. Ravi 'Rapid development of auricular prosthesis using CAD and rapid prototyping technologies' International Journal of Oral & Maxillofacial Surgery 2007; 36: 938-943 doi:10.1016/j.ijom.2007.07.013. © The International Society for Prosthetics and Orthotics 2014.

  17. Reverse engineering--rapid prototyping of the skull in forensic trauma analysis.

    PubMed

    Kettner, Mattias; Schmidt, Peter; Potente, Stefan; Ramsthaler, Frank; Schrodt, Michael

    2011-07-01

    Rapid prototyping (RP) comprises a variety of automated manufacturing techniques such as selective laser sintering (SLS), stereolithography, and three-dimensional printing (3DP), which use virtual 3D data sets to fabricate solid forms in a layer-by-layer technique. Despite a growing demand for (virtual) reconstruction models in daily forensic casework, maceration of the skull is frequently assigned to ensure haptic evidence presentation in the courtroom. Owing to the progress in the field of forensic radiology, 3D data sets of relevant cases are usually available to the forensic expert. Here, we present a first application of RP in forensic medicine using computed tomography scans for the fabrication of an SLS skull model in a case of fatal hammer impacts to the head. The report is intended to show that this method fully respects the dignity of the deceased and is consistent with medical ethics but nevertheless provides an excellent 3D impression of anatomical structures and injuries.

  18. Revision of complex acetabular defects using cages with the aid of rapid prototyping.

    PubMed

    Li, Huiwu; Wang, Liao; Mao, Yuanqing; Wang, You; Dai, Kerong; Zhu, Zhenan

    2013-12-01

    This study details a method using rapid prototyping (RP) technique to assist in acetabular revision with complex bone defects. Hemi-pelvic RP models were built among 25 patients with complex acetabular bone defects. Each patient was scheduled to undergo revision using either commercially available or customized cages based on individualized RP models. Average follow-up was 4.4 years (range, 1 to 9 years). The average Harris hip score was 36.1 (range, 20 to 58) preoperatively and reached an average of 82.6 (range, 60-96) at the last follow-up. No mechanical failure or loosening was observed. One patient experienced hip dislocation 4 days postoperatively. The resultant findings of this study merit consideration of RP as a helpful clinical complement for dealing with some complex bone defect of acetabulum. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. Test Structures Applied to the Rapid Prototyping of Sensors

    NASA Technical Reports Server (NTRS)

    Buehler, M.; Chang, L-J.; Martin, D.

    1997-01-01

    Recently, test structures were used to aid in the rapid development of a gas sensor and pressure sensor. These sensors were fabricated using co-fired ceramic technology and a multiproject approach. This talk will describe results obtained from a ceramic substrate which contained 36 chips with six variants including the sensors, process control monitors, and an interconnect chip. As far as the authors know, this is the first implementation of multi-projects in co-fired ceramic substrate. The gas sensor is being developed for the Space Shuttle and the pressure gage is being developed as a Martian barometer.

  20. Test Structures Applied to the Rapid Prototyping of Sensors

    NASA Technical Reports Server (NTRS)

    Buehler, M.; Chang, L-J.; Martin, D.

    1997-01-01

    Recently, test structures were used to aid in the rapid development of a gas sensor and pressure sensor. These sensors were fabricated using co-fired ceramic technology and a multiproject approach. This talk will describe results obtained from a ceramic substrate which contained 36 chips with six variants including the sensors, process control monitors, and an interconnect chip. As far as the authors know, this is the first implementation of multi-projects in co-fired ceramic substrate. The gas sensor is being developed for the Space Shuttle and the pressure gage is being developed as a Martian barometer.

  1. Photogrammetry for rapid prototyping: development of noncontact 3D reconstruction technologies

    NASA Astrophysics Data System (ADS)

    Knyaz, Vladimir A.

    2002-04-01

    An important stage of rapid prototyping technology is generating computer 3D model of an object to be reproduced. Wide variety of techniques for 3D model generation exists beginning with manual 3D models generation and finishing with full-automated reverse engineering system. The progress in CCD sensors and computers provides the background for integration of photogrammetry as an accurate 3D data source with CAD/CAM. The paper presents the results of developing photogrammetric methods for non-contact spatial coordinates measurements and generation of computer 3D model of real objects. The technology is based on object convergent images processing for calculating its 3D coordinates and surface reconstruction. The hardware used for spatial coordinates measurements is based on PC as central processing unit and video camera as image acquisition device. The original software for Windows 9X realizes the complete technology of 3D reconstruction for rapid input of geometry data in CAD/CAM systems. Technical characteristics of developed systems are given along with the results of applying for various tasks of 3D reconstruction. The paper describes the techniques used for non-contact measurements and the methods providing metric characteristics of reconstructed 3D model. Also the results of system application for 3D reconstruction of complex industrial objects are presented.

  2. CAD/CAM bilateral ear prostheses construction for Treacher Collins syndrome patients using laser scanning and rapid prototyping.

    PubMed

    Ciocca, Leonardo; De Crescenzio, Francesca; Fantini, Massimiliano; Scotti, Roberto

    2010-06-01

    Ear defects in patients affected by Treacher Collins syndrome necessitate the replacement of the existing anatomic residuals of the ears with custom-made prostheses. This paper describes a multidisciplinary protocol involving both medicine and computer-aided design/computer-aided manufacturing for manufacturing ear prostheses. Using innovative prototyping technologies together with conventional silicone processing procedures, a step-by-step procedure is presented. The complete workflow includes laser scanning of the defective regions of a patient's face, the use of 3D anatomic models from an ear digital library and rapid prototyping of both substructures for bar anchoring and moulds for silicone processing.

  3. Rapid Laser Prototyping Of Polymer-Based Nanoplasmonic Components

    NASA Astrophysics Data System (ADS)

    Stepanov, A. L.; Kiyan, R.; Reinhardt, C.; Seidel, A.; Pas-Singer, S.; Chichkov, B. N.

    Renewed and growing interest in the field of surface plasmon polaritons (SPPs) comes from a rapid advance of nanostructuring technologies. The application of two-photon polymerization technique for the fabrication of dielectric and metallic SPP-structures, which can be used for localization, guiding, and manipulation of SPPs waves on a subwavelength scale, is studied. This technology is based on nonlinear absorption of near-infrared femtosecond laser pulses. Excitation, propagation, and interaction of SPP waves with nanostructures are controlled and studied by leakage radiation imaging. It is demonstrated that created nanostructures on metal film are very efficient for the excitation and focusing of SPPs. Examples of passive and active SPP components are presented and discussed.

  4. Rapid prototyping and parametric optimization of plastic acoustofluidic devices for blood-bacteria separation.

    PubMed

    Silva, R; Dow, P; Dubay, R; Lissandrello, C; Holder, J; Densmore, D; Fiering, J

    2017-09-01

    Acoustic manipulation has emerged as a versatile method for microfluidic separation and concentration of particles and cells. Most recent demonstrations of the technology use piezoelectric actuators to excite resonant modes in silicon or glass microchannels. Here, we focus on acoustic manipulation in disposable, plastic microchannels in order to enable a low-cost processing tool for point-of-care diagnostics. Unfortunately, the performance of resonant acoustofluidic devices in plastic is hampered by a lack of a predictive model. In this paper, we build and test a plastic blood-bacteria separation device informed by a design of experiments approach, parametric rapid prototyping, and screening by image-processing. We demonstrate that the new device geometry can separate bacteria from blood while operating at 275% greater flow rate as well as reduce the power requirement by 82%, while maintaining equivalent separation performance and resolution when compared to the previously published plastic acoustofluidic separation device.

  5. Freeform multiphoton excited microfabrication for biological applications using a rapid prototyping CAD-based approach

    NASA Astrophysics Data System (ADS)

    Cunningham, Lawrence P.; Veilleux, Matthew P.; Campagnola, Paul J.

    2006-09-01

    Multiphoton excited polymerization has attracted increasing attention as a powerful 3 dimensional nano/microfabrication tool. The nonlinear excitation confines the fabrication region to the focal volume allowing the potential to achieve freeform fabrication with submicron capabilities. We report the adaptation and use of a computer aided design (CAD) approach, based on rapid prototyping software, which exploits this potential for fabricating with protein and polymers in biologically compatible aqueous environments. 3D structures are drawn in the STL format creating a solid model that can be sliced, where the individual sections are then serially fabricated without overwriting previous layers. The method is shown for potential biological applications including microfluidics, cell entrapment, and tissue engineering.

  6. A case series of rapid prototyping and intraoperative imaging in orbital reconstruction.

    PubMed

    Lim, Christopher G T; Campbell, Duncan I; Cook, Nicholas; Erasmus, Jason

    2015-06-01

    In Christchurch Hospital, rapid prototyping (RP) and intraoperative imaging are the standard of care in orbital trauma and has been used since February 2013. RP allows the fabrication of an anatomical model to visualize complex anatomical structures which is dimensionally accurate and cost effective. This assists diagnosis, planning, and preoperative implant adaptation for orbital reconstruction. Intraoperative imaging involves a computed tomography scan during surgery to evaluate surgical implants and restored anatomy and allows the clinician to correct errors in implant positioning that may occur during the same procedure. This article aims to demonstrate the potential clinical and cost saving benefits when both these technologies are used in orbital reconstruction which minimize the need for revision surgery.

  7. Fabrication of a Cranial Prosthesis Combined with an Ocular Prosthesis Using Rapid Prototyping: A Case Report

    PubMed Central

    Shankaran, Gayatri; Dhirawani, Rajesh

    2016-01-01

    Rapid prototyping (RP) is a technique of manufacturing parts by the additive layer manufacturing technology; where, a three-dimensional (3D) model created in a computer aided design (CAD) system is sectioned into 2D profiles, which are further constructed by RP layer by layer. Its use is not limited to industrial or engineering fields and has extended to the medical field for the manufacturing of custom implants and prostheses, the study of anatomy and surgical planning. Nowadays, dentists are more frequently encountered with the individuals affected with craniofacial defects due to trauma. In such cases, the craniomaxillofacial rehabilitation is a real challenge to bring the patients back to society and promote their well-being. The conventional impression technique for facial prosthesis fabrication has the disadvantage of deforming the soft tissue and causing discomfort for the patient. Herein, we describe the fabrication of a cranial prosthesis combined with an ocular prosthesis with RP and stereolithography. PMID:27536331

  8. A Case Series of Rapid Prototyping and Intraoperative Imaging in Orbital Reconstruction

    PubMed Central

    Lim, Christopher G.T.; Campbell, Duncan I.; Cook, Nicholas; Erasmus, Jason

    2014-01-01

    In Christchurch Hospital, rapid prototyping (RP) and intraoperative imaging are the standard of care in orbital trauma and has been used since February 2013. RP allows the fabrication of an anatomical model to visualize complex anatomical structures which is dimensionally accurate and cost effective. This assists diagnosis, planning, and preoperative implant adaptation for orbital reconstruction. Intraoperative imaging involves a computed tomography scan during surgery to evaluate surgical implants and restored anatomy and allows the clinician to correct errors in implant positioning that may occur during the same procedure. This article aims to demonstrate the potential clinical and cost saving benefits when both these technologies are used in orbital reconstruction which minimize the need for revision surgery. PMID:26000080

  9. A rapid prototyping/artificial intelligence approach to space station-era information management and access

    NASA Technical Reports Server (NTRS)

    Carnahan, Richard S., Jr.; Corey, Stephen M.; Snow, John B.

    1989-01-01

    Applications of rapid prototyping and Artificial Intelligence techniques to problems associated with Space Station-era information management systems are described. In particular, the work is centered on issues related to: (1) intelligent man-machine interfaces applied to scientific data user support, and (2) the requirement that intelligent information management systems (IIMS) be able to efficiently process metadata updates concerning types of data handled. The advanced IIMS represents functional capabilities driven almost entirely by the needs of potential users. Space Station-era scientific data projected to be generated is likely to be significantly greater than data currently processed and analyzed. Information about scientific data must be presented clearly, concisely, and with support features to allow users at all levels of expertise efficient and cost-effective data access. Additionally, mechanisms for allowing more efficient IIMS metadata update processes must be addressed. The work reported covers the following IIMS design aspects: IIMS data and metadata modeling, including the automatic updating of IIMS-contained metadata, IIMS user-system interface considerations, including significant problems associated with remote access, user profiles, and on-line tutorial capabilities, and development of an IIMS query and browse facility, including the capability to deal with spatial information. A working prototype has been developed and is being enhanced.

  10. Rapid prototyping of flexible intrafascicular electrode arrays by picosecond laser structuring.

    PubMed

    Mueller, Matthias; de la Oliva, Natalia; Del Valle, Jaume; Delgado Martinez, Ignacio; Navarro, Xavier; Stieglitz, Thomas

    2017-07-11

    Interfacing the peripheral nervous system can be performed with a large variety of electrode arrays. However, stimulating and recording a nerve while having a reasonable amount of channels limits the number of available systems. Translational research towards human clinical trial requires device safety and biocompatibility but would benefit from design flexibility in the development process to individualize probes. Approach. We selected established medical grade implant materials like precious metals and parylene C to develop a rapid prototyping process for novel intrafascicular electrode arrays using a picosecond laser structuring. A design for a rodent animal model was developed in conjunction with an intrafascicular implantation strategy. Electrode characterization and optimization was performed first in saline solution in vitro before performance and biocompatibility were validated in sciatic nerves of rats in chronic implantation. Main Results. The novel fabrication process proved to be suitable for prototyping and building intrafascicular electrode arrays. Electrochemical properties of the electrode sites were enhanced and tested for long-term stability. Chronic implantation in the sciatic nerve of rats showed good biocompatibility, selectivity and stable stimulation thresholds. Significance. Established medical grade materials can be used for intrafascicular nerve electrode arrays when laser structuring defines structure size in the micro-scale. Design flexibility reduces re-design cycle time and material certificates are beneficial support for safety studies on the way to clinical trials. Creative Commons Attribution license.

  11. Motion Planning for a Direct Metal Deposition Rapid Prototyping System

    SciTech Connect

    AMES,ARLO L.; HENSINGER,DAVID M.; KUHLMANN,JOEL L.

    1999-10-18

    A motion planning strategy was developed and implemented to generate motion control instructions from solid model data for controlling a robotically driven solid free-form fabrication process. The planning strategy was tested using a PUMA type robot arm integrated into a LENS{trademark} (Laser Engineered Net Shape) system. Previous systems relied on a series of x, y, and z stages, to provide a minimal coordinated motion control capability. This limited the complexity of geometries that could be constructed. With the coordinated motion provided by a robotic arm, the system can produce three dimensional parts by ''writing'' material onto any face of existing material. The motion planning strategy relied on solid model geometry evaluation and exploited robotic positioning flexibility to allow the construction of geometrically complex parts. The integration of the robotic manipulator into the LENS{trademark} system was tested by producing metal parts directly from CAD models.

  12. Evaluation of the Diagnostic Accuracy of Prototype Rapid Tests for Human African Trypanosomiasis

    PubMed Central

    Sternberg, Jeremy M.; Gierliński, Marek; Biéler, Sylvain; Ferguson, Michael A. J.; Ndung'u, Joseph M.

    2014-01-01

    Background Diagnosis of human African trypanosomiasis (HAT) remains a challenge both for active screening, which is critical in control of the disease, and in the point-of-care scenario where early and accurate diagnosis is essential. Recently, the first field deployment of a lateral flow rapid diagnostic test (RDT) for HAT, “SD BIOLINE HAT” has taken place. In this study, we evaluated the performance of “SD BIOLINE HAT” and two new prototype RDTs. Methodology/Principal Findings The performance of “SD BIOLINE HAT” and 2 prototype RDTs was tested using archived plasma from 250 Trypanosoma brucei gambiense patients, and 250 endemic controls. As well as comparison of the sensitivity and specificity of each device, the performance of individual antigens was assessed and the hypothetical performance of novel antigen combinations extrapolated. Neither of the prototype devices were inferior in sensitivity or specificity to “SD BIOLINE HAT” (sensitivity 0.82±0.01, specificity 0.97±0.01, 95% CI) at the 5% margins, while one of the devices (BBI) had significantly superior sensitivity (0.88±0.03). Analysis of the performance of individual antigens was used to model new antigen combinations to be explored in development of the next generation of HAT RDTs. The modelling showed that an RDT using two recombinant antigens (rLiTat1.5 and rISG65) would give a performance similar to the best devices in this study, and would also offer the most robust performance under deteriorating field conditions. Conclusions/Significance Both “SD BIOLINE HAT” and the prototype devices performed comparably well to one another and also to the published performance range of the card agglutination test for trypanosomiasis in sensitivity and specificity. The performance of individual antigens enabled us to predict that an all-recombinant antigen RDT can be developed with an accuracy equivalent to “ SD BIOLINE HAT.” Such an RDT would have advantages in simplified manufacture

  13. Development of Experimental Setup of Metal Rapid Prototyping Machine using Selective Laser Sintering Technique

    NASA Astrophysics Data System (ADS)

    Patil, S. N.; Mulay, A. V.; Ahuja, B. B.

    2016-08-01

    Unlike in the traditional manufacturing processes, additive manufacturing as rapid prototyping, allows designers to produce parts that were previously considered too complex to make economically. The shift is taking place from plastic prototype to fully functional metallic parts by direct deposition of metallic powders as produced parts can be directly used for desired purpose. This work is directed towards the development of experimental setup of metal rapid prototyping machine using selective laser sintering and studies the various parameters, which plays important role in the metal rapid prototyping using SLS technique. The machine structure in mainly divided into three main categories namely, (1) Z-movement of bed and table, (2) X-Y movement arrangement for LASER movements and (3) feeder mechanism. Z-movement of bed is controlled by using lead screw, bevel gear pair and stepper motor, which will maintain the accuracy of layer thickness. X-Y movements are controlled using timing belt and stepper motors for precise movements of LASER source. Feeder mechanism is then developed to control uniformity of layer thickness metal powder. Simultaneously, the study is carried out for selection of material. Various types of metal powders can be used for metal RP as Single metal powder, mixture of two metals powder, and combination of metal and polymer powder. Conclusion leads to use of mixture of two metals powder to minimize the problems such as, balling effect and porosity. Developed System can be validated by conducting various experiments on manufactured part to check mechanical and metallurgical properties. After studying the results of these experiments, various process parameters as LASER properties (as power, speed etc.), and material properties (as grain size and structure etc.) will be optimized. This work is mainly focused on the design and development of cost effective experimental setup of metal rapid prototyping using SLS technique which will gives the feel of

  14. Manufacturing of microcirculation phantoms using rapid prototyping technologies.

    PubMed

    Buchoux, Anthony; Valluri, Prashant; Smith, Stewart; Stokes, Adam A; Hoskins, Peter R; Sboros, Vassilis

    2015-01-01

    In this paper, we describe a method for the manufacturing of a microcirculation phantom that may be used to investigate hemodynamics using optics based methods. We made an Acrylonitrile Butadiene Styrene (ABS) negative mold, manufactured in a Fused Deposition Modelling (FDM) printer, embedded it in Polydimethysilioxane (PDMS) and dissolved it from within using acetone. We successfully made an enlarged three-dimensional (3D) network of microcirculation, and tested it using red blood cell (RBC) analogues. This phantom may be used for testing medical imaging technology.

  15. FPGA/FPAA-based rapid prototyping environment for mixed signal systems

    NASA Astrophysics Data System (ADS)

    Ganesan, Sreelakshmi P.; Vemuri, Ranga

    1999-08-01

    In this paper, we present a rapid prototyping environment for mixed signal systems. The environment consists of programmable mixed signal hardware together with a set of integrated CAD tools to enable fast prototyping of mixed signal designs from high-level specifications. The prototyping hardware comprises of field-programmable analog arrays and field-programmable gate arrays on which the analog and digital sections of the design are respectively implemented. Field-programmable interconnect routes signals between multiple devices. A bank of data converters constitutes the interface between the analog and digital parts. Design tools are required to map the given design onto the prototyping hardware. The high-level design specification is first compiled into an intermediate format suitable for synthesis. Following this, the design is partitioned into analog and digital sections. The analog and digital subsystems are synthesized for the target FPAA and FPGA devices respectively. Configuration bitstreams are generated and downloaded on to the respective devices.

  16. Accuracy of templates for navigated implantation made by rapid prototyping with DICOM datasets of cone beam computer tomography (CBCT).

    PubMed

    Weitz, Jochen; Deppe, Herbert; Stopp, Sebastian; Lueth, Tim; Mueller, Steffen; Hohlweg-Majert, Bettina

    2011-12-01

    The aim of this study is to evaluate the accuracy of a surgical template-aided implant placement produced by rapid prototyping using a DICOM dataset from cone beam computer tomography (CBCT). On the basis of CBCT scans (Sirona® Galileos), a total of ten models were produced using a rapid-prototyping three-dimensional printer. On the same patients, impressions were performed to compare fitting accuracy of both methods. From the models made by impression, templates were produced and accuracy was compared and analyzed with the rapid-prototyping model. Whereas templates made by conventional procedure had an excellent accuracy, the fitting accuracy of those produced by DICOM datasets was not sufficient. Deviations ranged between 2.0 and 3.5 mm, after modification of models between 1.4 and 3.1 mm. The findings of this study suggest that the accuracy of the low-dose Sirona Galileos® DICOM dataset seems to show a high deviation, which is not useable for accurate surgical transfer for example in implant surgery.

  17. Technical note: rapid prototyping of 3D grid arrays for image guided therapy quality assurance.

    PubMed

    Kittle, David; Holshouser, Barbara; Slater, James M; Guenther, Bob D; Pitsianis, Nikos P; Pearlstein, Robert D

    2008-12-01

    Three dimensional grid phantoms offer a number of advantages for measuring imaging related spatial inaccuracies for image guided surgery and radiotherapy. The authors examined the use of rapid prototyping technology for directly fabricating 3D grid phantoms from CAD drawings. We tested three different fabrication process materials, photopolymer jet with acrylic resin (PJ/AR), selective laser sintering with polyamide (SLS/P), and fused deposition modeling with acrylonitrile butadiene styrene (FDM/ABS). The test objects consisted of rectangular arrays of control points formed by the intersections of posts and struts (2 mm rectangular cross section) and spaced 8 mm apart in the x, y, and z directions. The PJ/AR phantom expanded after immersion in water which resulted in permanent warping of the structure. The surface of the FDM/ABS grid exhibited a regular pattern of depressions and ridges from the extrusion process. SLS/P showed the best combination of build accuracy, surface finish, and stability. Based on these findings, a grid phantom for assessing machine-dependent and frame-induced MR spatial distortions was fabricated to be used for quality assurance in stereotactic neurosurgical and radiotherapy procedures. The spatial uniformity of the SLS/P grid control point array was determined by CT imaging (0.6 x 0.6 x 0.625 mm3 resolution) and found suitable for the application, with over 97.5% of the control points located within 0.3 mm of the position specified in CAD drawing and none of the points off by more than 0.4 mm. Rapid prototyping is a flexible and cost effective alternative for development of customized grid phantoms for medical physics quality assurance.

  18. Technical Note: Rapid prototyping of 3D grid arrays for image guided therapy quality assurance

    SciTech Connect

    Kittle, David; Holshouser, Barbara; Slater, James M.; Guenther, Bob D.; Pitsianis, Nikos P.; Pearlstein, Robert D.

    2008-12-15

    Three dimensional grid phantoms offer a number of advantages for measuring imaging related spatial inaccuracies for image guided surgery and radiotherapy. The authors examined the use of rapid prototyping technology for directly fabricating 3D grid phantoms from CAD drawings. We tested three different fabrication process materials, photopolymer jet with acrylic resin (PJ/AR), selective laser sintering with polyamide (SLS/P), and fused deposition modeling with acrylonitrile butadiene styrene (FDM/ABS). The test objects consisted of rectangular arrays of control points formed by the intersections of posts and struts (2 mm rectangular cross section) and spaced 8 mm apart in the x, y, and z directions. The PJ/AR phantom expanded after immersion in water which resulted in permanent warping of the structure. The surface of the FDM/ABS grid exhibited a regular pattern of depressions and ridges from the extrusion process. SLS/P showed the best combination of build accuracy, surface finish, and stability. Based on these findings, a grid phantom for assessing machine-dependent and frame-induced MR spatial distortions was fabricated to be used for quality assurance in stereotactic neurosurgical and radiotherapy procedures. The spatial uniformity of the SLS/P grid control point array was determined by CT imaging (0.6x0.6x0.625 mm{sup 3} resolution) and found suitable for the application, with over 97.5% of the control points located within 0.3 mm of the position specified in CAD drawing and none of the points off by more than 0.4 mm. Rapid prototyping is a flexible and cost effective alternative for development of customized grid phantoms for medical physics quality assurance.

  19. Reverse engineering and rapid prototyping techniques to innovate prosthesis socket design

    NASA Astrophysics Data System (ADS)

    Colombo, Giorgio; Bertetti, Massimiliano; Bonacini, Daniele; Magrassi, Grazia

    2006-02-01

    The paper presents an innovative approach totally based on digital data to optimize lower limb socket prosthesis design. This approach is based on a stump's detailed geometric model and provides a substitute to plaster cast obtained through the traditional manual methodology with a physical model, realized with Rapid Prototyping technologies; this physical model will be used for the socket lamination. The paper discusses a methodology to reconstruct a 3D geometric model of the stump able to describe with high accuracy and detail the complete structure subdivided into bones, soft tissues, muscular masses and dermis. Some different technologies are used for stump acquisition: non contact laser technique for external geometry, CT and MRI imaging technologies for the internal structure, the first one dedicated to bones geometrical model, the last for soft tissues and muscles. We discuss problems related to 3D geometric reconstruction: the patient and stump positioning for the different acquisitions, markers' definition on the stump to identify landmarks, alignment's strategies for the different digital models, in order to define a protocol procedure with a requested accuracy for socket's realization. Some case-studies illustrate the methodology and the results obtained.

  20. A Method to Represent Heterogeneous Materials for Rapid Prototyping: The Matryoshka Approach

    PubMed Central

    Lei, Shuangyan; Frank, Matthew C.; Anderson, Donald D.; Brown, Thomas D.

    2015-01-01

    Purpose The purpose of this paper is to present a new method for representing heterogeneous materials using nested STL shells, based, in particular, on the density distributions of human bones. Design/methodology/approach Nested STL shells, called Matryoshka models, are described, based on their namesake Russian nesting dolls. In this approach, polygonal models, such as STL shells, are “stacked” inside one another to represent different material regions. The Matryoshka model addresses the challenge of representing different densities and different types of bone when reverse engineering from medical images. The Matryoshka model is generated via an iterative process of thresholding the Hounsfield Unit (HU) data using computed tomography (CT), thereby delineating regions of progressively increasing bone density. These nested shells can represent regions starting with the medullary (bone marrow) canal, up through and including the outer surface of the bone. Findings The Matryoshka approach introduced can be used to generate accurate models of heterogeneous materials in an automated fashion, avoiding the challenge of hand-creating an assembly model for input to multi-material additive or subtractive manufacturing. Originality/Value This paper presents a new method for describing heterogeneous materials: in this case, the density distribution in a human bone. The authors show how the Matryoshka model can be used to plan harvesting locations for creating custom rapid allograft bone implants from donor bone. An implementation of a proposed harvesting method is demonstrated, followed by a case study using subtractive rapid prototyping to harvest a bone implant from a human tibia surrogate. PMID:26120277

  1. Utilizing a Rapid Prototyping Approach in the Building of a Hypermedia-Based Reference Station.

    ERIC Educational Resources Information Center

    Sell, Dan

    This paper discusses the building of a hypermedia-based reference station at the Wright Laboratory Technical Library, Wright-Patterson Air Force Base, Ohio. Following this, the paper focuses on an electronic user survey from which data is collected and analysis is made. The survey data is used in a rapid prototyping approach, which is defined as…

  2. A Rapidly Prototyped Vegetation Dryness Index Developed for Wildfire Risk Assessment at Stennis Space Center

    NASA Technical Reports Server (NTRS)

    Ross, Kenton; Graham, William D.; Prados, Donald; Spruce, Joseph

    2006-01-01

    A remote sensing index was developed to allow improved monitoring of vegetation dryness conditions on a regional basis. This remote sensing index was rapidly prototyped at Stennis Space Center in response to drought conditions in the local area in spring 2006.

  3. Low-Cost Rapid Prototyping of Whole-Glass Microfluidic Devices

    ERIC Educational Resources Information Center

    Yuen, Po Ki; Goral, Vasiliy N.

    2012-01-01

    A low-cost, straightforward, rapid prototyping of whole-glass microfluidic devices is presented using glass-etching cream that can be easily purchased in local stores. A self-adhered vinyl stencil cut out by a desktop digital craft cutter was used as an etching mask for patterning microstructures in glass using the glass-etching cream. A specific…

  4. Low-Cost Rapid Prototyping of Whole-Glass Microfluidic Devices

    ERIC Educational Resources Information Center

    Yuen, Po Ki; Goral, Vasiliy N.

    2012-01-01

    A low-cost, straightforward, rapid prototyping of whole-glass microfluidic devices is presented using glass-etching cream that can be easily purchased in local stores. A self-adhered vinyl stencil cut out by a desktop digital craft cutter was used as an etching mask for patterning microstructures in glass using the glass-etching cream. A specific…

  5. Rapid Prototyping of Computer-Based Presentations Using NEAT, Version 1.1.

    ERIC Educational Resources Information Center

    Muldner, Tomasz

    NEAT (iNtegrated Environment for Authoring in ToolBook) provides templates and various facilities for the rapid prototyping of computer-based presentations, a capability that is lacking in current authoring systems. NEAT is a specialized authoring system that can be used by authors who have a limited knowledge of computer systems and no…

  6. A Conceptual Framework and a Toolkit for Supporting the Rapid Prototyping of Context-Aware Applications.

    ERIC Educational Resources Information Center

    Dey, Anind K.; Abowd, Gregory D.; Salber, Daniel

    2001-01-01

    Discusses the trend toward ubiquitous computing and the challenge to enhance the behavior of any application by informing it of the context of its use. Defines context related to the interaction between humans, applications, and the surrounding environment; and presents a conceptual framework and a toolkit for supporting the rapid prototyping of…

  7. JTEC/WTEC panel report on rapid prototyping in Europe and Japan. Volume 2: Site reports

    SciTech Connect

    Prinz, F.B.; Atwood, C.L.; Aubin, R.F.

    1996-09-01

    This study reports the findings by a panel of experts on the state of the art in physical rapid prototyping technologies in Europe and Japan. The panel focused its investigation on a new class of rapid prototyping technologies called solid free form fabrication (SFF). The efforts observed overseas are compared to efforts in the US. The expert panel was selected by recommendations from the study chairman and representatives of the sponsoring agencies. The panel was formed of members from industry, academia, and government. Industry members represented primarily users rather than developers of SFF technology. The panel visited 34 sites in subgroups of typically three to five members. This Volume 2 of the final report from the JTEC/WTEC Panel on Rapid Prototyping in Europe and Japan. It consists of the site reports from the panel`s visits to rapid prototyping labs and development facilities in Europe and Japan. Volume 1, published separately, contains the panel`s analytical chapters and overall conclusions.

  8. Exemplars, Prototypes, and the Flexibility of Classification Models

    ERIC Educational Resources Information Center

    Olsson, Henrik; Wennerholm, Pia; Lyxzen, Urban

    2004-01-01

    J. P. Minda and J. D. Smith (2001) showed that a prototype model outperforms an exemplar model, especially in larger categories or categories that contained more complex stimuli. R. M. Nosofsky and S. R. Zaki (2002) showed that an exemplar model with a response-scaling mechanism outperforms a prototype model. The authors of the current study…

  9. Plan to procedure: combining 3D templating with rapid prototyping to enhance pedicle screw placement

    NASA Astrophysics Data System (ADS)

    Augustine, Kurt E.; Stans, Anthony A.; Morris, Jonathan M.; Huddleston, Paul M.; Matsumoto, Jane M.; Holmes, David R., III; Robb, Richard A.

    2010-02-01

    Spinal fusion procedures involving the implantation of pedicle screws have steadily increased over the past decade because of demonstrated improvement in biomechanical stability of the spine. However, current methods of spinal fusion carries a risk of serious vascular, visceral, and neurological injury caused by inaccurate placement or inappropriately sized instrumentation, which may lead to patient paralysis or even fatality. 3D spine templating software developed by the Biomedical Imaging Resource (BIR) at Mayo Clinic allows the surgeon to virtually place pedicle screws using pre-operative 3D CT image data. With the template plan incorporated, a patient-specific 3D anatomic model is produced using a commercial rapid prototyping system. The pre-surgical plan and the patient-specific model then are used in the procedure room to provide real-time visualization and quantitative guidance for accurate placement of each pedicle screw, significantly reducing risk of injury. A pilot study was conducted at Mayo Clinic by the Department of Radiology, the Department of Orthopedics, and the BIR, involving seven complicated pediatric spine cases. In each case, pre-operative 3D templating was carried out and patient specific models were generated. The plans and the models were used intra-operatively, providing precise pedicle screw starting points and trajectories. Postoperative assessment by the surgeon confirmed all seven operations were successful. Results from the study suggest that patient-specific, 3D anatomic models successfully acquired from 3D templating tools are valuable for planning and conducting pedicle screw insertion procedures.

  10. Compact form fitting small antennas using three-dimensional rapid prototyping

    NASA Astrophysics Data System (ADS)

    Willis, Bryan Jon

    Three-dimensional (3D) rapid prototyping holds significant promise for future antenna designs. Many complex designs that would be unmanufacturable or costly are realizable on a 3D printing machine. The ability to create 3D designs of virtually any configuration makes it possible to build compact antennas that can form fit to any space. These antennas build on the concept that small antennas can best reach the ideal operating limit when utilizing the entire 3D space in a sphere surrounding the antenna. Antennas require a combination of dielectric and conductive materials. 3D rapid prototyping is already well advanced for plastics and dielectric materials (with more options coming online). Prototyping with conductive materials has lagged behind; due mainly to their higher melting points, but this is advancing as well. This dissertation focuses on 3D rapid prototyping for antenna design. A 3D antenna made from small cubical cells is optimized for 2.4--3GHz using a genetic algorithm (GA). The antennas are built using 3D printing of plastic covered by conductive paint. The effects of the conductivity of the paint and number of layers on the resonance and gain of the antenna are evaluated. These results demonstrate the feasibility of using 3D rapid prototyping for antenna design. A 3D dipole is also optimized using a GA to function from 510--910MHz. The antenna was built using 3D rapid prototyping from plastic. The 3D antenna was covered with a conductive coating and measured, showing good agreement with simulation. The 3D GA is used to design 3D antennas of random shape to fit inside the empty space in a cell phone case and optimized for cell phone bands 800--900MHz and 1.6--3.7GHz. The research also evaluates methods and materials that can be used to produce 3D antennas. In addition to the flexibility that 3D prototyping brings to antenna design, this paper describes how this new and emerging method for building antennas can provide fast and affordable antennas for

  11. A review of trends and limitations in hydrogel-rapid prototyping for tissue engineering.

    PubMed

    Billiet, Thomas; Vandenhaute, Mieke; Schelfhout, Jorg; Van Vlierberghe, Sandra; Dubruel, Peter

    2012-09-01

    The combined potential of hydrogels and rapid prototyping technologies has been an exciting route in developing tissue engineering scaffolds for the past decade. Hydrogels represent to be an interesting starting material for soft, and lately also for hard tissue regeneration. Their application enables the encapsulation of cells and therefore an increase of the seeding efficiency of the fabricated structures. Rapid prototyping techniques on the other hand, have become an elegant tool for the production of scaffolds with the purpose of cell seeding and/or cell encapsulation. By means of rapid prototyping, one can design a fully interconnected 3-dimensional structure with pre-determined dimensions and porosity. Despite this benefit, some of the rapid prototyping techniques are not or less suitable for the generation of hydrogel scaffolds. In this review, we therefore give an overview on the different rapid prototyping techniques suitable for the processing of hydrogel materials. A primary distinction will be made between (i) laser-based, (ii) nozzle-based, and (iii) printer-based systems. Special attention will be addressed to current trends and limitations regarding the respective techniques. Each of these techniques will be further discussed in terms of the different hydrogel materials used so far. One major drawback when working with hydrogels is the lack of mechanical strength. Therefore, maintaining and improving the mechanical integrity of the processed scaffolds has become a key issue regarding 3-dimensional hydrogel structures. This limitation can either be overcome during or after processing the scaffolds, depending on the applied technology and materials. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Rapid prototyping of three-dimensional biomodels as an adjuvant in the surgical planning for intracranial aneurysms.

    PubMed

    Erbano, Bruna Olandoski; Opolski, Ana Cristina; Olandoski, Marcia; Foggiatto, José Aguiomar; Kubrusly, Luiz Fernando; Dietz, Ulrich Andreas; Zini, Cassio; Marinho, Melissa Mitsue Makita Arantes; Leal, André Giacomelli; Ramina, Ricardo

    2013-11-01

    To fabricate a three-dimensional biomodels of intracranial aneurysms, using rapid prototyping technology, to facilitate optimal anatomical visualization of aneurysms prior to and during surgery. Four intracranial aneurysms cases were selected for this study. Using CT angiography images, the rapid prototyping process was completed using a PolyJet technology machine. The size and morphology of the prototypes were compared to brain digital subtraction arteriography of the same patients. The biomodels reproduced the exact location and morphology of the intracranial aneurysms, particularly the necks, in life-size dimensions and exactly the same as measured by digital subtraction arteriography. The arterial segments adjacent to the aneurysm and arteries anatomically known by the surgeon were also shown, which could guide the surgeon to the aneurysmal segment. The models showed an average unit cost of US$ 130 and each one took an average of 20 hours to be fabricated. It is possible to fabricate 3D physical biomodels of intracranial aneurysms from CT angiography images. These prototypes may be useful in the surgical planning for intracranial aneurysms to clarify the anatomy, define surgical techniques and facilitate the choice of suitable materials, such as clips and clip appliers.

  13. Computer-aided design and rapid prototyping-assisted contouring of costal cartilage graft for facial reconstructive surgery.

    PubMed

    Lee, Shu Jin; Lee, Heow Pueh; Tse, Kwong Ming; Cheong, Ee Cherk; Lim, Siak Piang

    2012-06-01

    Complex 3-D defects of the facial skeleton are difficult to reconstruct with freehand carving of autogenous bone grafts. Onlay bone grafts are hard to carve and are associated with imprecise graft-bone interface contact and bony resorption. Autologous cartilage is well established in ear reconstruction as it is easy to carve and is associated with minimal resorption. In the present study, we aimed to reconstruct the hypoplastic orbitozygomatic region in a patient with left hemifacial microsomia using computer-aided design and rapid prototyping to facilitate costal cartilage carving and grafting. A three-step process of (1) 3-D reconstruction of the computed tomographic image, (2) mirroring the facial skeleton, and (3) modeling and rapid prototyping of the left orbitozygomaticomalar region and reconstruction template was performed. The template aided in donor site selection and extracorporeal contouring of the rib cartilage graft to allow for an accurate fit of the graft to the bony model prior to final fixation in the patient. We are able to refine the existing computer-aided design and rapid prototyping methods to allow for extracorporeal contouring of grafts and present rib cartilage as a good alternative to bone for autologous reconstruction.

  14. Models of Rapid Solidification

    NASA Technical Reports Server (NTRS)

    Gilmer, G. H.; Broughton, J. Q.

    1984-01-01

    Laser annealing studies provide much information on various consequences of rapid solidification, including the trapping of impurities in the crystal, the generation of vacancies and twins, and on the fundamental limits to the speed of the crystal-melt interface. Some results obtained by molecular dynamics methods of the solidification of a Lennard-Jones liquid are reviewed. An indication of the relationship of interface speed to undercooling for certain materials can be derived from this model. Ising model simulations of impurity trapping in silicon are compared with some of the laser annealing results. The consequences of interface segregation and atomic strain are discussed.

  15. Models of Rapid Solidification

    NASA Technical Reports Server (NTRS)

    Gilmer, G. H.; Broughton, J. Q.

    1984-01-01

    Laser annealing studies provide much information on various consequences of rapid solidification, including the trapping of impurities in the crystal, the generation of vacancies and twins, and on the fundamental limits to the speed of the crystal-melt interface. Some results obtained by molecular dynamics methods of the solidification of a Lennard-Jones liquid are reviewed. An indication of the relationship of interface speed to undercooling for certain materials can be derived from this model. Ising model simulations of impurity trapping in silicon are compared with some of the laser annealing results. The consequences of interface segregation and atomic strain are discussed.

  16. Application of Systems Engineering to Rapid Prototyping for Close Air Support

    DTIC Science & Technology

    2009-10-01

    FRIENDLY MARKING DEvICE (FMD) IN SPIRAL CONTEXT Determine objectives, alternatives , and constraints Commit to an approach for the next iteration Plan the...3 Prototype 2 Operational Prototype Models Evaluate alternatives Cumulative cost Partition Review Develop the deliverables for the iteration and...patterns: An introduction to object-oriented analysis and design and iterative development (3rd ed.). Upper Saddle River, NJ: Prentice Hall PTR. Maier, M

  17. Rapid prototyping of microfluidic chips for dead-volume-free MS coupling.

    PubMed

    Dietze, Claudia; Scholl, Tobias; Ohla, Stefan; Appun, Johannes; Schneider, Christoph; Belder, Detlev

    2015-11-01

    A fast and straightforward method to prototype microfluidic chip systems for dead-volume-free hyphenation to electrospray-ionisation mass spectrometry is presented. The developed approach based on liquid-phase lithography provides an inexpensive and reliable access to microfluidic chips for MS coupling which can be manufactured in any laboratory with low technical demands. The rapid prototyping approach enables the seamless integration of capillaries serving as electrospray emitters with negligible dead volume. The high versatility of the presented prototyping method and the applicability of a variety of chip-based devices in different fields of lab-on-a-chip technology are established for analytical separations by means of chip-electrochromatography-MS and for continuous-flow synthesis using microreactor technology with MS detection.

  18. Justification of rapid prototyping in the development cycle of thermoplastic-based lab-on-a-chip.

    PubMed

    Preywisch, Regina; Ritzi-Lehnert, Marion; Drese, Klaus S; Röser, Tina

    2011-11-01

    During the developmental cycle of lab-on-a-chip devices, various microstructuring techniques are required. While in the designing and assay implementation phase direct structuring or so-called rapid-prototyping methods such as milling or laser ablation are applied, replication methods like hot embossing or injection moulding are favourable for large quantity manufacturing. This work investigated the applicability of rapid-prototyping techniques for thermoplastic chip development in general, and the reproducibility of performances in dependency of the structuring technique. A previously published chip for prenatal diagnosis that preconcentrates DNA via electrokinetic trapping and field-amplified-sample-stacking and afterwards separates it in CGE was chosen as a model. The impact of structuring, sealing, and the integration of membranes on the mobility of the EOF, DNA preconcentration, and DNA separation was studied. Structuring methods were found to significantly change the location where preconcentration of DNA occurs. However, effects on the mobility of the EOF and the separation quality of DNA were not observed. Exchange of the membrane has no effect on the chip performance, whereas the sealing method impairs the separation of DNA within the chip. The overall assay performance is not significantly influenced by different structuring methods; thus, the application of rapid-prototyping methods during a chip development cycle is well justified. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. New Design for Rapid Prototyping of Digital Master Casts for Multiple Dental Implant Restorations

    PubMed Central

    Romero, Luis; Jiménez, Mariano; Espinosa, María del Mar; Domínguez, Manuel

    2015-01-01

    Aim This study proposes the replacement of all the physical devices used in the manufacturing of conventional prostheses through the use of digital tools, such as 3D scanners, CAD design software, 3D implants files, rapid prototyping machines or reverse engineering software, in order to develop laboratory work models from which to finish coatings for dental prostheses. Different types of dental prosthetic structures are used, which were adjusted by a non-rotatory threaded fixing system. Method From a digital process, the relative positions of dental implants, soft tissue and adjacent teeth of edentulous or partially edentulous patients has been captured, and a maser working model which accurately replicates data relating to the patients oral cavity has been through treatment of three-dimensional digital data. Results Compared with the conventional master cast, the results show a significant cost savings in attachments, as well as an increase in the quality of reproduction and accuracy of the master cast, with the consequent reduction in the number of patient consultation visits. The combination of software and hardware three-dimensional tools allows the optimization of the planning of dental implant-supported rehabilitations protocol, improving the predictability of clinical treatments and the production cost savings of master casts for restorations upon implants. PMID:26696528

  20. Rapid prototyping and evaluation of programmable SIMD SDR processors in LISA

    NASA Astrophysics Data System (ADS)

    Chen, Ting; Liu, Hengzhu; Zhang, Botao; Liu, Dongpei

    2013-03-01

    With the development of international wireless communication standards, there is an increase in computational requirement for baseband signal processors. Time-to-market pressure makes it impossible to completely redesign new processors for the evolving standards. Due to its high flexibility and low power, software defined radio (SDR) digital signal processors have been proposed as promising technology to replace traditional ASIC and FPGA fashions. In addition, there are large numbers of parallel data processed in computation-intensive functions, which fosters the development of single instruction multiple data (SIMD) architecture in SDR platform. So a new way must be found to prototype the SDR processors efficiently. In this paper we present a bit-and-cycle accurate model of programmable SIMD SDR processors in a machine description language LISA. LISA is a language for instruction set architecture which can gain rapid model at architectural level. In order to evaluate the availability of our proposed processor, three common baseband functions, FFT, FIR digital filter and matrix multiplication have been mapped on the SDR platform. Analytical results showed that the SDR processor achieved the maximum of 47.1% performance boost relative to the opponent processor.

  1. Rapid Prototyping of Polymeric Nanopillars by 3D Direct Laser Writing for Controlling Cell Behavior.

    PubMed

    Buch-Månson, Nina; Spangenberg, Arnaud; Gomez, Laura Piedad Chia; Malval, Jean-Pierre; Soppera, Olivier; Martinez, Karen L

    2017-08-23

    Mammalian cells have been widely shown to respond to nano- and microtopography that mimics the extracellular matrix. Synthetic nano- and micron-sized structures are therefore of great interest in the field of tissue engineering, where polymers are particularly attractive due to excellent biocompatibility and versatile fabrication methods. Ordered arrays of polymeric pillars provide a controlled topographical environment to study and manipulate cells, but processing methods are typically either optimized for the nano- or microscale. Here, we demonstrate polymeric nanopillar (NP) fabrication using 3D direct laser writing (3D DLW), which offers a rapid prototyping across both size regimes. The NPs are interfaced with NIH3T3 cells and the effect of tuning geometrical parameters of the NP array is investigated. Cells are found to adhere on a wide range of geometries, but the interface depends on NP density and length. The Cell Interface with Nanostructure Arrays (CINA) model is successfully extended to predict the type of interface formed on different NP geometries, which is found to correlate with the efficiency of cell alignment along the NPs. The combination of the CINA model with the highly versatile 3D DLW fabrication thus holds the promise of improved design of polymeric NP arrays for controlling cell growth.

  2. New Design for Rapid Prototyping of Digital Master Casts for Multiple Dental Implant Restorations.

    PubMed

    Romero, Luis; Jiménez, Mariano; Espinosa, María Del Mar; Domínguez, Manuel

    2015-01-01

    This study proposes the replacement of all the physical devices used in the manufacturing of conventional prostheses through the use of digital tools, such as 3D scanners, CAD design software, 3D implants files, rapid prototyping machines or reverse engineering software, in order to develop laboratory work models from which to finish coatings for dental prostheses. Different types of dental prosthetic structures are used, which were adjusted by a non-rotatory threaded fixing system. From a digital process, the relative positions of dental implants, soft tissue and adjacent teeth of edentulous or partially edentulous patients has been captured, and a maser working model which accurately replicates data relating to the patients oral cavity has been through treatment of three-dimensional digital data. Compared with the conventional master cast, the results show a significant cost savings in attachments, as well as an increase in the quality of reproduction and accuracy of the master cast, with the consequent reduction in the number of patient consultation visits. The combination of software and hardware three-dimensional tools allows the optimization of the planning of dental implant-supported rehabilitations protocol, improving the predictability of clinical treatments and the production cost savings of master casts for restorations upon implants.

  3. Wine Traceability: A Data Model and Prototype in Albanian Context.

    PubMed

    Vukatana, Kreshnik; Sevrani, Kozeta; Hoxha, Elira

    2016-02-17

    Vine traceability is a critical issue that has gained interest internationally. Quality control programs and schemes are mandatory in many countries including EU members and the USA. Albania has transformed most of the EU regulations on food into laws. Regarding the vine sector, the obligation of wine producers to keep traceability data is part of the legislation. The analysis on the interviews conducted with Albanian winemakers show that these data are actually recorded only in hard copy. Another fact that emerges from the interviews is that only two producers have implemented the ISO (International Organization for Standardization) standards on food. The purpose of this paper is to develop an agile and automated traceability system based on these standards. We propose a data model and system prototype that are described in the second and third section of this work. The data model is an adaption along the lines of the GS1 (Global Standards One) specifications for a wine supply chain. The proposed prototype has a key component that is mobile access to the information about wine through barcode technology. By using this mechanism the consumer obtains transparency on his expectations concerning the quality criteria. Another important component of the proposed system in this paper is a real-time notification module that works as an alert system when a risk is identified. This can help producers and authorities to have a rapid identification of a contaminated product. It is important in cases when recalling the product from the market or preventing it from reaching the consumer.

  4. Evaluation of a rapid prototyping process for microsystems for silicon microstructures

    NASA Astrophysics Data System (ADS)

    Bange, Stefan; Herding, Mark; Woias, Peter

    2003-01-01

    During the last decade rapid prototyping has made a tremendous success in almost every branch of industrial fabrication. Almost every article of today"s life is pre-fabricated in a rapid process during its design. Functional rapid prototypes represent an increasing share, as they allow realistic functional tests of a component in an early stage of development. MEMS technology is still at the beginning of the rapid prototyping aera. Up to now, only a few conventional techniques, like stereolithography, have been downscaled to create rapid microprototypes with a limited choice of materials and geometries. Rapid prototyping of silicon is completely out of reach today. In this paper we propose a micro rapid prototyping concept for functional silicon microstructures. The process combines laser technology with standard processes of silicon microstructuring and has been evaluated with a metal-silicon layer system. First, noble metal is vapour deposited on top of a silicon wafer. The metal is subsequently structured with a laser, thus creating a mask, which can be transferred into the silicon by standard chemical etching procedures like KOH-etch. The advantage of this concept is that the time-consuming photomask generation is omitted completely, as the laser can be guided with CAD data. Moreover, the standard structuring process gives the opportunity to gain a microstructure with features equivalent to the final component. With laser ablation and KOH-etch two process steps are being carried out subsequently, which are inevitably linked to each other. Depending on the energy of the laser irradiation the ablation performance changes and, with it, the minimal structure width and the thermal melting zone at the edges of the mask openings. If the energy density is too high the crystalline structure of the silicon is destroyed by heat transfer and heat conduction. Hereby the anisotropic etch resistance is lost, which influences the following KOH-etch process. At the current

  5. Design Principles for Rapid Prototyping Forces Sensors using 3D Printing

    PubMed Central

    Kesner, Samuel B.; Howe, Robert D.

    2011-01-01

    Force sensors provide critical information for robot manipulators, manufacturing processes, and haptic interfaces. Commercial force sensors, however, are generally not adapted to specific system requirements, resulting in sensors with excess size, cost, and fragility. To overcome these issues, 3D printers can be used to create components for the quick and inexpensive development of force sensors. Limitations of this rapid prototyping technology, however, require specialized design principles. In this paper, we discuss techniques for rapidly developing simple force sensors, including selecting and attaching metal flexures, using inexpensive and simple displacement transducers, and 3D printing features to aid in assembly. These design methods are illustrated through the design and fabrication of a miniature force sensor for the tip of a robotic catheter system. The resulting force sensor prototype can measure forces with an accuracy of as low as 2% of the 10 N measurement range. PMID:21874102

  6. A rapid prototyping facility for flight research in advanced systems concepts

    NASA Technical Reports Server (NTRS)

    Duke, Eugene L.; Brumbaugh, Randal W.; Disbrow, James D.

    1989-01-01

    The Dryden Flight Research Facility of the NASA Ames Research Facility of the NASA Ames Research Center is developing a rapid prototyping facility for flight research in flight systems concepts that are based on artificial intelligence (AI). The facility will include real-time high-fidelity aircraft simulators, conventional and symbolic processors, and a high-performance research aircraft specially modified to accept commands from the ground-based AI computers. This facility is being developed as part of the NASA-DARPA automated wingman program. This document discusses the need for flight research and for a national flight research facility for the rapid prototyping of AI-based avionics systems and the NASA response to those needs.

  7. Rapid prototyping facility for flight research in artificial-intelligence-based flight systems concepts

    NASA Technical Reports Server (NTRS)

    Duke, E. L.; Regenie, V. A.; Deets, D. A.

    1986-01-01

    The Dryden Flight Research Facility of the NASA Ames Research Facility of the NASA Ames Research Center is developing a rapid prototyping facility for flight research in flight systems concepts that are based on artificial intelligence (AI). The facility will include real-time high-fidelity aircraft simulators, conventional and symbolic processors, and a high-performance research aircraft specially modified to accept commands from the ground-based AI computers. This facility is being developed as part of the NASA-DARPA automated wingman program. This document discusses the need for flight research and for a national flight research facility for the rapid prototyping of AI-based avionics systems and the NASA response to those needs.

  8. Design Principles for Rapid Prototyping Forces Sensors using 3D Printing.

    PubMed

    Kesner, Samuel B; Howe, Robert D

    2011-07-21

    Force sensors provide critical information for robot manipulators, manufacturing processes, and haptic interfaces. Commercial force sensors, however, are generally not adapted to specific system requirements, resulting in sensors with excess size, cost, and fragility. To overcome these issues, 3D printers can be used to create components for the quick and inexpensive development of force sensors. Limitations of this rapid prototyping technology, however, require specialized design principles. In this paper, we discuss techniques for rapidly developing simple force sensors, including selecting and attaching metal flexures, using inexpensive and simple displacement transducers, and 3D printing features to aid in assembly. These design methods are illustrated through the design and fabrication of a miniature force sensor for the tip of a robotic catheter system. The resulting force sensor prototype can measure forces with an accuracy of as low as 2% of the 10 N measurement range.

  9. Enhancements to ASHRAE Standard 90.1 Prototype Building Models

    SciTech Connect

    Goel, Supriya; Athalye, Rahul A.; Wang, Weimin; Zhang, Jian; Rosenberg, Michael I.; Xie, YuLong; Hart, Philip R.; Mendon, Vrushali V.

    2014-04-16

    This report focuses on enhancements to prototype building models used to determine the energy impact of various versions of ANSI/ASHRAE/IES Standard 90.1. Since the last publication of the prototype building models, PNNL has made numerous enhancements to the original prototype models compliant with the 2004, 2007, and 2010 editions of Standard 90.1. Those enhancements are described here and were made for several reasons: (1) to change or improve prototype design assumptions; (2) to improve the simulation accuracy; (3) to improve the simulation infrastructure; and (4) to add additional detail to the models needed to capture certain energy impacts from Standard 90.1 improvements. These enhancements impact simulated prototype energy use, and consequently impact the savings estimated from edition to edition of Standard 90.1.

  10. An architecture for rapid prototyping of control schemes for artificial ventricles.

    PubMed

    Ficola, Antonio; Pagnottelli, Stefano; Valigi, Paolo; Zoppitelli, Maurizio

    2004-01-01

    This paper presents an experimental system aimed at rapid prototyping of feedback control schemes for ventricular assist devices, and artificial ventricles in general. The system comprises a classical mock circulatory system, an actuated bellow-based ventricle chamber, and a software architecture for control schemes implementation and experimental data acquisition, visualization and storing. Several experiments have been carried out, showing good performance of ventricular pressure tracking control schemes.

  11. Low-Cost Inkjet Printing Technology for the Rapid Prototyping of Transducers

    PubMed Central

    Andò, Bruno; Baglio, Salvatore; Bulsara, Adi R.; Emery, Teresa; Marletta, Vincenzo; Pistorio, Antonio

    2017-01-01

    Recently, there has been an upsurge in efforts dedicated to developing low-cost flexible electronics by exploiting innovative materials and direct printing technologies. This interest is motivated by the need for low-cost mass-production, shapeable, and disposable devices, and the rapid prototyping of electronics and sensors. This review, following a short overview of main printing processes, reports examples of the development of flexible transducers through low-cost inkjet printing technology. PMID:28368318

  12. Reconstruction of Frontal Bone With Custom-Made Prosthesis Using Rapid Prototyping.

    PubMed

    Florentino, Vinícius Gabriel Barros; Mendonça, Diego Santiago de; Bezerra, Ariel Valente; Silva, Leonardo de Freitas; Pontes, Rafael Figueirêdo; Melo, Carlos Vinícius Mota de; Mello, Manoel de Jesus Rodrigues; de Aguiar, Andréa Silvia Walter

    2016-06-01

    Frontal bone fracture treatment is still an issue of research in craniofacial surgery and neurosurgery. The aims of the treatment are to reduce the complication risks and to keep the aesthetic of the face. Before the management of this fracture type, it is necessary to consider the permanence or not of the frontal sinus function. Rapid prototyping has been an aid tool on planning and simulation of the surgical procedure, improving the diagnostic quality and the implant manufacture, beyond reducing the operative time. Among the used materials on treatment of these fractures, titanium mesh shows large versatility and ease of handling. Poly(methyl methacrylate) has been used in defects of partial thickness or irregularities on cranial surface. The aim of this study is to report a case of a patient presenting sequelae of large fracture of anterior wall of frontal bone, treated by a titanium mesh associated with the customized poly(methyl methacrylate) implant from the rapid prototyping. It could be concluded that the use of this technique showed itself effective on patient treatment, and rapid prototyping demonstrated being a valuable tool showing predictable and satisfactory results.

  13. Programmatic Perspectives on Using `Rapid Prototyping Capability' for Water Management Applications Using NASA Products

    NASA Astrophysics Data System (ADS)

    Toll, D.; Friedl, L.; Entin, J.; Engman, E.

    2006-12-01

    The NASA Water Management Program addresses concerns and decision making related to water availability, water forecast and water quality. The goal of the Water Management Program Element is to encourage water management organizations to use NASA Earth science data, models products, technology and other capabilities in their decision support tools (DSTs) for problem solving. The goal of the NASA Rapid Prototyping Capability (RPC) is to speed the evaluation of these NASA products and technologies to improve current and future DSTs by reducing the time to access, configure, and assess the effectiveness of NASA products and technologies. The NASA Water Management Program Element partners with Federal agencies, academia, private firms, and may include international organizations. Currently, the NASA Water Management Program oversees eight application projects. However, water management is a very broad descriptor of a much larger number of activities that are carried out to insure safe and plentiful water supply for humans, industry and agriculture, promote environmental stewardship, and mitigate disaster such as floods and droughts. The goal of this presentation is to summarize how the RPC may further enhance the effectiveness of using NASA products for water management applications.

  14. Polyurethane from biosource as a new material for fabrication of microfluidic devices by rapid prototyping.

    PubMed

    Piccin, Evandro; Coltro, Wendell Karlos Tomazelli; Fracassi da Silva, José Alberto; Neto, Salvador Claro; Mazo, Luiz Henrique; Carrilho, Emanuel

    2007-11-30

    This paper presents the use of elastomeric polyurethane (PU), derived from castor oil (CO) biosource, as a new material for fabrication of microfluidic devices by rapid prototyping. Including the irreversible sealing step, PU microchips were fabricated in less than 1h by casting PU resin directly on the positive high-relief molds fabricated by standard photolithography and nickel electrodeposition. Physical characterization of microchannels was performed by scanning electron microscopy (SEM) and profilometry. Polymer surface was characterized using contact angle measurements and the results showed that the hydrophilicity of the PU surface increases after oxygen plasma treatment. The polymer surface demonstrated the capability of generating an electroosmotic flow (EOF) of 2.6 x 10(-4)cm(2)V(-1)s(-1) at pH 7 in the cathode direction, which was characterized by current monitoring method at different pH values. The compatibility of PU with a wide range of solvents and electrolytes was tested by determining its degree of swelling over a 24h period of contact. The performance of microfluidic systems fabricated using this new material was evaluated by fabricating miniaturized capillary electrophoresis systems. Epinephrine and l-DOPA, as model analytes, were separated in aqueous solutions and detected with end-channel amperometric detection.

  15. Processing of pure Ti by rapid prototyping based on laser cladding

    NASA Astrophysics Data System (ADS)

    Arias-González, F.; del Val, J.; Comesaña, R.; Lusquiños, F.; Quintero, F.; Riveiro, A.; Boutinguiza, M.; Pou, J.

    2013-11-01

    Rapid prototyping based on laser cladding is an additive manufacturing (AM) process based on the overlapping of cladding tracks to produce functional components. Powder or wire are fed into a melting pool created using laser radiation as a heat source and the relative movement between the beam and the work piece makes possible to generate pieces layer-by-layer. This technique can be applied for any material which can be melted and the components can be manufactured directly according to a computer aided design (CAD) model. Additive manufacturing is particularly interesting to produce titanium components because, in this case, the loss of material produced by subtractive manufacturing methods is highly costly. Moreover, titanium and its alloys are widely used in biomedical, aircraft, chemical and marine industries due to their biocompatibility, excellent corrosion resistance and superior strength-to-weight ratio. In this research work, a near-infrared laser delivering a maximum power of 500W is used to produce pure titanium thin parts. Dimensions and surface morphology are characterized using Optical Microscopy (OM) and Scanning Electron Microscopy (SEM), the hardness by nanoindentation and the composition by X-Ray Diffraction (XRD) and Energy Dispersive X-Ray Spectroscopy (EDS). The aim of this work is to establish the conditions under which satisfactory properties are obtained and to understand the relationship between microstructure/properties and deposition parameters.

  16. Novel grinding stone used for polishing 3D plastic replica with rapid prototyping technology

    NASA Astrophysics Data System (ADS)

    Feng, Wang; Niikura, Yoshihiro; Sato, Toshio; Kawashima, Norimichi

    2006-01-01

    Rapid prototyping (RP) apparatus accepts a specific format translated from CAD data (patient's CT) and "slices" it into two-dimensional cross sections for laser photo curing. Surgeon can conduct safer surgery by reappearing on an actual model using 3D plastic replica in the preoperative. Polishing has to be used to eliminate the marks after removal of supports and the build layer pitches. Complicated and narrow areas of the 3D replica are difficult to be polished with the conventional grinding stone. This study proposes a novel grinding stone and introduces its producing process and characteristics. The novel grinding stone has many advantages as follows; (1) Preparation is possible of grinding stone that follows the complicated shape. (2) Grinding stone with uniformly dispersed abrasive grains can be prepared using magnetic particles and magnetic field. (3) Reshaping of grinding stone by heating is possible since the binder is made of a thermoplastic resin. (4) Every process can easily be carried out. We could polish to eliminate the marks after removal of supports and the build layer pitches on 3D plastic replica surface with the grinding stone.

  17. Active deformable sheets: prototype implementation, modeling, and control

    NASA Astrophysics Data System (ADS)

    Lind, Robert J.; Johnson, Norbert; Doumanidis, Charalabos C.

    2000-06-01

    Active deformable sheets are integrated smart planar sheet structures performing off-plane deformations under computer actuation and control, to take up a desired dynamic morphology specified in CAD software or obtained by 3-D scanning of a solid surface. The sheet prototypes are implemented in the laboratory by elastic neoprene foil layers with embedded asymmetric grids of SMA wires (Nitinol), which upon electrical contraction bend the sheet to the necessary local curvature distribution. An analytical model of such prototypes, consisting of an electrical, a thermal, a material and a mechanical module, as well as a more complex finite element thermomechanical simulation of the sheet structure have been developed and validated experimentally. Besides open-loop control of the sheet curvatures by modulation of the SMA wire actuation current, a closed-loop control system has been implemented, using feedback of the wire electrical resistance measurements in real time, correlating to the material transformation state. The active deformable sheets are intended for applications such as reconfigurable airfoils and aerospace structures, variable focal length optics and electromagnetic reflectors, flexible and rapid tooling and microrobotics.

  18. Rapid Prototyping of Inspired Gas Delivery System for Pulmonary MRI Research

    PubMed Central

    Cook, Fredrick Roscoe; Geier, Eric T.; Asadi, Amran K.; Sá, Rui Carlos; Prisk, G. Kim

    2016-01-01

    Specific ventilation imaging (SVI) is a noninvasive magnetic resonance imaging (MRI)-based method for determining the regional distribution of inspired air in the lungs, useful for the assessment of pulmonary function in medical research. This technique works by monitoring the rate of magnetic resonance signal change in response to a series of imposed step changes in inspired oxygen concentration. The current SVI technique requires a complex system of tubes, valves, and electronics that are used to supply and rapidly switch inspired gases while subjects are imaged, which makes the technique difficult to translate into the clinical setting. This report discusses the design and implementation of custom three-dimensional (3D) printed hardware that greatly simplifies SVI measurement of lung function. Several hardware prototypes were modeled using computer-aided design software and printed for evaluation. After finalization of the design, the new delivery system was evaluated based on O2 and N2 concentration step responses and validated against the current SVI protocol. The design performed rapid switching of supplied gas within 250 ms and consistently supplied the desired concentration of O2 during operation. It features a reduction in the number of commercial hardware components, from five to one, and a reduction in the number of gas lines between the operator’s room and the scanner room, from four to one, as well as a substantially reduced preparation time from 25 to 5 min. 3D printing is well suited to the design of inexpensive custom MRI compatible hardware, making it particularly useful in imaging-based research. PMID:27917393

  19. Rapid tooling for functional prototyping of metal mold processes. CRADA final report

    SciTech Connect

    Zacharia, T.; Ludtka, G.M.; Bjerke, M.A.; Gray, W.H.

    1997-12-01

    The overall scope of this endeavor was to develop an integrated computer system, running on a network of heterogeneous computers, that would allow the rapid development of tool designs, and then use process models to determine whether the initial tooling would have characteristics which produce the prototype parts. The major thrust of this program for ORNL was the definition of the requirements for the development of the integrated die design system with the functional purpose to link part design, tool design, and component fabrication through a seamless software environment. The principal product would be a system control program that would coordinate the various application programs and implement the data transfer so that any networked workstation would be useable. The overall system control architecture was to be required to easily facilitate any changes, upgrades, or replacements of the model from either the manufacturing end or the design criteria standpoint. The initial design of such a program is described in the section labeled ``Control Program Design``. A critical aspect of this research was the design of the system flow chart showing the exact system components and the data to be transferred. All of the major system components would have been configured to ensure data file compatibility and transferability across the Internet. The intent was to use commercially available packages to model the various manufacturing processes for creating the die and die inserts in addition to modeling the processes for which these parts were to be used. In order to meet all of these requirements, investigative research was conducted to determine the system flow features and software components within the various organizations contributing to this project. This research is summarized.

  20. Rapid Prototyping Amphiphilic Polymer/Hydroxyapatite Composite Scaffolds with Hydration-Induced Self-Fixation Behavior

    PubMed Central

    Kutikov, Artem B.; Gurijala, Anvesh

    2015-01-01

    Two major factors hampering the broad use of rapid prototyped biomaterials for tissue engineering applications are the requirement for custom-designed or expensive research-grade three-dimensional (3D) printers and the limited selection of suitable thermoplastic biomaterials exhibiting physical characteristics desired for facile surgical handling and biological properties encouraging tissue integration. Properly designed thermoplastic biodegradable amphiphilic polymers can exhibit hydration-dependent hydrophilicity changes and stiffening behavior, which may be exploited to facilitate the surgical delivery/self-fixation of the scaffold within a physiological tissue environment. Compared to conventional hydrophobic polyesters, they also present significant advantages in blending with hydrophilic osteoconductive minerals with improved interfacial adhesion for bone tissue engineering applications. Here, we demonstrated the excellent blending of biodegradable, amphiphilic poly(D,L-lactic acid)-poly(ethylene glycol)-poly(D,L-lactic acid) (PLA-PEG-PLA) (PELA) triblock co-polymer with hydroxyapatite (HA) and the fabrication of high-quality rapid prototyped 3D macroporous composite scaffolds using an unmodified consumer-grade 3D printer. The rapid prototyped HA-PELA composite scaffolds and the PELA control (without HA) swelled (66% and 44% volume increases, respectively) and stiffened (1.38-fold and 4-fold increases in compressive modulus, respectively) in water. To test the hypothesis that the hydration-induced physical changes can translate into self-fixation properties of the scaffolds within a confined defect, a straightforward in vitro pull-out test was designed to quantify the peak force required to dislodge these scaffolds from a simulated cylindrical defect at dry versus wet states. Consistent with our hypothesis, the peak fixation force measured for the PELA and HA-PELA scaffolds increased 6-fold and 15-fold upon hydration, respectively. Furthermore, we showed that

  1. Rapid prototyping amphiphilic polymer/hydroxyapatite composite scaffolds with hydration-induced self-fixation behavior.

    PubMed

    Kutikov, Artem B; Gurijala, Anvesh; Song, Jie

    2015-03-01

    Two major factors hampering the broad use of rapid prototyped biomaterials for tissue engineering applications are the requirement for custom-designed or expensive research-grade three-dimensional (3D) printers and the limited selection of suitable thermoplastic biomaterials exhibiting physical characteristics desired for facile surgical handling and biological properties encouraging tissue integration. Properly designed thermoplastic biodegradable amphiphilic polymers can exhibit hydration-dependent hydrophilicity changes and stiffening behavior, which may be exploited to facilitate the surgical delivery/self-fixation of the scaffold within a physiological tissue environment. Compared to conventional hydrophobic polyesters, they also present significant advantages in blending with hydrophilic osteoconductive minerals with improved interfacial adhesion for bone tissue engineering applications. Here, we demonstrated the excellent blending of biodegradable, amphiphilic poly(D,L-lactic acid)-poly(ethylene glycol)-poly(D,L-lactic acid) (PLA-PEG-PLA) (PELA) triblock co-polymer with hydroxyapatite (HA) and the fabrication of high-quality rapid prototyped 3D macroporous composite scaffolds using an unmodified consumer-grade 3D printer. The rapid prototyped HA-PELA composite scaffolds and the PELA control (without HA) swelled (66% and 44% volume increases, respectively) and stiffened (1.38-fold and 4-fold increases in compressive modulus, respectively) in water. To test the hypothesis that the hydration-induced physical changes can translate into self-fixation properties of the scaffolds within a confined defect, a straightforward in vitro pull-out test was designed to quantify the peak force required to dislodge these scaffolds from a simulated cylindrical defect at dry versus wet states. Consistent with our hypothesis, the peak fixation force measured for the PELA and HA-PELA scaffolds increased 6-fold and 15-fold upon hydration, respectively. Furthermore, we showed that

  2. Habitat Demonstration Unit Project: Leadership and Management Strategies for a Rapid Prototyping Project

    NASA Technical Reports Server (NTRS)

    Kennedy, Kriss J.; Toup, Larry; Gill, Tracy; Tri, Terry; Howe, Scott; Smitherman, David

    2011-01-01

    This paper gives an overview of the National Aeronautics and Space Administration (NASA) led multi-center Habitat Demonstration Unit (HDU) project leadership and management strategies being used by the NASA HDU team for a rapid prototyping project. The HDU project team constructed and tested an analog prototype lunar surface habitat/laboratory called the Pressurized Excursion Module (PEM) during 2010. The prototype unit subsystems were integrated in a short amount of time, utilizing a tiger team rapid prototyping approach that brought together over 20 habitation-related technologies and innovations from a variety of NASA centers. This paper describes the leadership and management strategies as well as lessons learned pertaining to leading and managing a multi-center diverse team in a rapid prototype environment. The PEM configuration went from a paper design to an operational surface habitat demonstration unit in less than 12 months. The HDU project is part of the strategic plan from the Exploration Systems Mission Directorate (ESMD) Directorate Integration Office (DIO) and the Exploration Mission Systems Office (EMSO) to test destination elements in analog environments. The 2011 HDU-Deep Space Habitat (DSH) configuration will build upon the PEM work, and emphasize validity of crew operations (remote working and living), EVA operations, mission operations, logistics operations, and science operations that might be required in a deep space context for Near Earth Object (NEO) exploration mission architectures. The 2011 HDU-DSH will be field-tested during the 2011 Desert Research and Technologies Studies (DRaTS) field tests. The HDU project is a "technology-pull" project that integrates technologies and innovations from multiple NASA centers. This project will repurpose the HDU 2010 demo unit that was field tested in the 2010 DRaTS, adding habitation functionality to the prototype unit. This paper will describe the strategy of establishing a multi-center project

  3. SOAR telescope control system: a rapid prototype and development in LabVIEW

    NASA Astrophysics Data System (ADS)

    Ashe, Michael C.; Schumacher, German

    2000-06-01

    A Rapid Prototype and full development plan of the SOAR TCS is reviewed to show advances in: (1) Prototyping speed, which makes implementation and test of features faster than specification under older methods. This allows the development environment and prototype modules to become partners with and part of the specification documents. (2) Real-Time performance and reliability through use of RT Linux. (3) Visually Rich GUI development that allows an emphasis on `seeing' versus `reading'. (4) Long-Term DataLogging and Internet subscription service of all desired variables with instant recall of historical trend data. (5) A `plug-in' software architecture which enables rapid reconfiguration and reuse of the system and/or plug-ins utilizing LabVIEW graphical modules, a scripting language engine (in LabVIEW) and encapsulation of interfaces in `instrument-driver' style `plug-in' modules. (6) A platform- independent development environment and distributed architecture allowing secure internet observation and control via every major OS and hardware platform.

  4. Engineering Models Ease and Speed Prototyping

    NASA Technical Reports Server (NTRS)

    2008-01-01

    NASA astronauts plan to return to the Moon as early as 2015 and establish a lunar base, from which 6-month flights to Mars would be launched by 2030. Essential to this plan is the Ares launch vehicle, NASA s next-generation spacecraft that will, in various iterations, be responsible for transporting all equipment and personnel to the Moon, Mars, and beyond for the foreseeable future. The Ares launch vehicle is powered by the J-2X propulsion system, with what will be the world s largest rocket nozzles. One of the conditions that engineers carefully consider in designing rocket nozzles particularly large ones is called separation phenomenon, which occurs when outside ambient air is sucked into the nozzle rim by the relatively low pressures of rapidly expanding exhaust gasses. This separation of exhaust gasses from the side-wall imparts large asymmetric transverse loads on the nozzle, deforming the shape and thus perturbing exhaust flow to cause even greater separation. The resulting interaction can potentially crack the nozzle or break actuator arms that control thrust direction. Side-wall loads are extremely difficult to measure directly, and, until now, techniques were not available for accurately predicting the magnitude and frequency of the loads. NASA researchers studied separation phenomenon in scale-model rocket nozzles, seeking to use measured vibration on these nozzle replicas to calculate the unknown force causing the vibrations. Key to this approach was the creation of a computer model accurately representing the nozzle as well as the test cell.

  5. Rapid and low-cost prototyping of medical devices using 3D printed molds for liquid injection molding.

    PubMed

    Chung, Philip; Heller, J Alex; Etemadi, Mozziyar; Ottoson, Paige E; Liu, Jonathan A; Rand, Larry; Roy, Shuvo

    2014-06-27

    Biologically inert elastomers such as silicone are favorable materials for medical device fabrication, but forming and curing these elastomers using traditional liquid injection molding processes can be an expensive process due to tooling and equipment costs. As a result, it has traditionally been impractical to use liquid injection molding for low-cost, rapid prototyping applications. We have devised a method for rapid and low-cost production of liquid elastomer injection molded devices that utilizes fused deposition modeling 3D printers for mold design and a modified desiccator as an injection system. Low costs and rapid turnaround time in this technique lower the barrier to iteratively designing and prototyping complex elastomer devices. Furthermore, CAD models developed in this process can be later adapted for metal mold tooling design, enabling an easy transition to a traditional injection molding process. We have used this technique to manufacture intravaginal probes involving complex geometries, as well as overmolding over metal parts, using tools commonly available within an academic research laboratory. However, this technique can be easily adapted to create liquid injection molded devices for many other applications.

  6. Rapid and Low-cost Prototyping of Medical Devices Using 3D Printed Molds for Liquid Injection Molding

    PubMed Central

    Chung, Philip; Heller, J. Alex; Etemadi, Mozziyar; Ottoson, Paige E.; Liu, Jonathan A.; Rand, Larry; Roy, Shuvo

    2014-01-01

    Biologically inert elastomers such as silicone are favorable materials for medical device fabrication, but forming and curing these elastomers using traditional liquid injection molding processes can be an expensive process due to tooling and equipment costs. As a result, it has traditionally been impractical to use liquid injection molding for low-cost, rapid prototyping applications. We have devised a method for rapid and low-cost production of liquid elastomer injection molded devices that utilizes fused deposition modeling 3D printers for mold design and a modified desiccator as an injection system. Low costs and rapid turnaround time in this technique lower the barrier to iteratively designing and prototyping complex elastomer devices. Furthermore, CAD models developed in this process can be later adapted for metal mold tooling design, enabling an easy transition to a traditional injection molding process. We have used this technique to manufacture intravaginal probes involving complex geometries, as well as overmolding over metal parts, using tools commonly available within an academic research laboratory. However, this technique can be easily adapted to create liquid injection molded devices for many other applications. PMID:24998993

  7. The Influence of Depth of Cut, Feed Rate, and Step-over on Dimensional Accuracy in Subtractive Rapid Prototyping of Polycarbonate Material

    NASA Astrophysics Data System (ADS)

    Suteja, T. J.

    2017-03-01

    Subtractive rapid prototyping is fast and automatic three dimensions physical modelling that uses computer aided design model as the input. The dimensional accuracy of the result of the subtractive rapid prototyping is influenced by its process parameters. The aim of this research is to study and then develop a model that shows the influence of depth of cut, feed rate, and step-over on the vertical length error, horizontal length error, and depth error in subtractive rapid prototyping of polycarbonate material. This research implements response surface methodology to develop the model and then followed by the residual tests to evaluate the developed model. The result shows that the increase of the feed rate and the step-over will increase the horizontal dimension error. The most influenced factor on the horizontal dimension error is the step-over. Meanwhile, the vertical dimension error will be affected mostly by the step-over. Last, the depth error is influenced by the feed rate, the step-over, and the depth of cut. The depth of cut is the most critical factor that increases the depth error. The developed models give an insight on how several process parameters of rapid prototyping will influence the dimensional accuracy of a polycarbonate material. Based on the model, efficient resources utilization can be achieved.

  8. Rapid prototyping of zirconium diboride/copper electrical discharge machining electrodes

    NASA Astrophysics Data System (ADS)

    Stucker, Brent Eric

    The acceptance of rapid prototyping (RP) as the predominant technique for producing polymer and paper parts directly from computer-aided design (CAD) models has led many corporations and universities to try to extend its capabilities to more robust materials. In addition to producing prototype metal and ceramic parts, a significant effort has been made to create parts that are useful as tools and dies or that reduce the time necessary to create tools and dies. Most materials used for tools and dies are very hard, because they need to be able to withstand millions of cycles before failing. Electrical discharge machining (EDM) is the most common method used to machine tools and dies out of hard materials. A method for producing EDM electrodes using RP could greatly reduce the time and cost involved in creating tools and dies. A new EDM electrode material made up of zirconium diboride and copper (ZrBsb2/Cu) that is superior to traditional EDM electrodes has been investigated. The processing techniques necessary for creating Zrsb2/Cu electrodes from powders of ZrB2 and copper have been developed. These ZrBsb2/Cu electrodes have a better wear ratio and a faster sink rate than graphite, copper or tungsten/copper EDM electrodes. Performance variables that were tracked are: (1) wear ratio, (2) sink rate and (3) surface finish, where ZrBsb2/Cu, copper, graphite and W/Cu were used as anodes (electrodes) and stainless steel as cathodes (workpieces). The ZrBsb2/Cu electrode material system retains its superior EDM electrode performance across a number of materials processing and compositional variations. Scanning electron microscopy (SEM) was used to study the electrodes after EDM. These SEM observations facilitated an understanding of the superior EDM electrode performance characteristics of ZrBsb2/Cu to traditional EDM electrode material systems. A method for creating geometrically-complex ZrBsb2/Cu EDM electrodes using the selective laser sintering (SLS) RP technique was

  9. Rapid prototyping and inclined plane technique in the treatment of maxillofacial malformations in a fox.

    PubMed

    Freitas, Elisangela P; Rahal, Sheila C; Teixeira, Carlos R; Silva, Jorge V L; Noritomi, Pedro Y; Villela, Carlos H S; Yamashita, Seizo

    2010-03-01

    An approximately 9-month-old fox (Pseudalopex vetulus) was presented with malocclusion and deviation of the lower jaw to the right side. Orthodontic treatment was performed using the inclined plane technique. Virtual 3D models and prototypes of the head were based on computed tomography (CT) image data to assist in diagnosis and treatment.

  10. Rapid prototyping and inclined plane technique in the treatment of maxillofacial malformations in a fox

    PubMed Central

    Freitas, Elisangela P.; Rahal, Sheila C.; Teixeira, Carlos R.; Silva, Jorge V.L.; Noritomi, Pedro Y.; Villela, Carlos H.S.; Yamashita, Seizo

    2010-01-01

    An approximately 9-month-old fox (Pseudalopex vetulus) was presented with malocclusion and deviation of the lower jaw to the right side. Orthodontic treatment was performed using the inclined plane technique. Virtual 3D models and prototypes of the head were based on computed tomography (CT) image data to assist in diagnosis and treatment. PMID:20514249

  11. Ultra-rapid prototyping of flexible, multi-layered microfluidic devices via razor writing.

    PubMed

    Cosson, Steffen; Aeberli, Luc G; Brandenberg, Nathalie; Lutolf, Matthias P

    2015-01-07

    The fabrication of microfluidic devices is often still a time-consuming and costly process. Here we introduce a very simple and cheap microfabrication process based on "razor writing", also termed xurography, for the ultra-rapid prototyping of microfluidic devices. Thin poly(dimethylsiloxane) (PDMS) membranes are spin-coated on flexible plastic foil and cut into user-defined shapes with a bench-top cutter plotter. The PDMS membranes can then be assembled into desirable microdevices via plasma bonding. The plastic foil allows manipulation of exceptionally thin (30-300 μm) PDMS layers and can be readily peeled after fabrication. This versatile technique can be used to produce a wide variety of microfluidic device prototypes within just a few hours.

  12. Design of anthropomorphic flow phantoms based on rapid prototyping of compliant vessel geometries.

    PubMed

    Lai, Simon S M; Yiu, Billy Y S; Poon, Alexander K K; Yu, Alfred C H

    2013-09-01

    Anatomically realistic flow phantoms are essential experimental tools for vascular ultrasound. Here we describe how these flow phantoms can be efficiently developed via a rapid prototyping (RP) framework that involves direct fabrication of compliant vessel geometries. In this framework, anthropomorphic vessel models were drafted in computer-aided design software, and they were fabricated using stereolithography (one type of RP). To produce elastic vessels, a compliant photopolymer was used for stereolithography. We fabricated a series of compliant, diseased carotid bifurcation models with eccentric stenosis (50%) and plaque ulceration (types I and III), and they were used to form thin-walled flow phantoms by coupling the vessels to an agar-based tissue-mimicking material. These phantoms were found to yield Doppler spectrograms with significant spectral broadening and color flow images with mosaic patterns, as typical of disturbed flow under stenosed and ulcerated disease conditions. Also, their wall distension behavior was found to be similar to that observed in vivo, and this corresponded with the vessel wall's average elastic modulus (391 kPa), which was within the nominal range for human arteries. The vessel material's acoustic properties were found to be sub-optimal: the estimated average acoustic speed was 1801 m/s, and the attenuation coefficient was 1.58 dB/(mm·MHz(n)) with a power-law coefficient of 0.97. Such an acoustic mismatch nevertheless did not notably affect our Doppler spectrograms and color flow image results. These findings suggest that phantoms produced from our design framework have the potential to serve as ultrasound-compatible test beds that can simulate complex flow dynamics similar to those observed in real vasculature. Copyright © 2013 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  13. The MOLGENIS toolkit: rapid prototyping of biosoftware at the push of a button.

    PubMed

    Swertz, Morris A; Dijkstra, Martijn; Adamusiak, Tomasz; van der Velde, Joeri K; Kanterakis, Alexandros; Roos, Erik T; Lops, Joris; Thorisson, Gudmundur A; Arends, Danny; Byelas, George; Muilu, Juha; Brookes, Anthony J; de Brock, Engbert O; Jansen, Ritsert C; Parkinson, Helen

    2010-12-21

    There is a huge demand on bioinformaticians to provide their biologists with user friendly and scalable software infrastructures to capture, exchange, and exploit the unprecedented amounts of new *omics data. We here present MOLGENIS, a generic, open source, software toolkit to quickly produce the bespoke MOLecular GENetics Information Systems needed. The MOLGENIS toolkit provides bioinformaticians with a simple language to model biological data structures and user interfaces. At the push of a button, MOLGENIS' generator suite automatically translates these models into a feature-rich, ready-to-use web application including database, user interfaces, exchange formats, and scriptable interfaces. Each generator is a template of SQL, JAVA, R, or HTML code that would require much effort to write by hand. This 'model-driven' method ensures reuse of best practices and improves quality because the modeling language and generators are shared between all MOLGENIS applications, so that errors are found quickly and improvements are shared easily by a re-generation. A plug-in mechanism ensures that both the generator suite and generated product can be customized just as much as hand-written software. In recent years we have successfully evaluated the MOLGENIS toolkit for the rapid prototyping of many types of biomedical applications, including next-generation sequencing, GWAS, QTL, proteomics and biobanking. Writing 500 lines of model XML typically replaces 15,000 lines of hand-written programming code, which allows for quick adaptation if the information system is not yet to the biologist's satisfaction. Each application generated with MOLGENIS comes with an optimized database back-end, user interfaces for biologists to manage and exploit their data, programming interfaces for bioinformaticians to script analysis tools in R, Java, SOAP, REST/JSON and RDF, a tab-delimited file format to ease upload and exchange of data, and detailed technical documentation. Existing databases

  14. Linear DNA for rapid prototyping of synthetic biological circuits in an Escherichia coli based TX-TL cell-free system.

    PubMed

    Sun, Zachary Z; Yeung, Enoch; Hayes, Clarmyra A; Noireaux, Vincent; Murray, Richard M

    2014-06-20

    Accelerating the pace of synthetic biology experiments requires new approaches for rapid prototyping of circuits from individual DNA regulatory elements. However, current testing standards require days to weeks due to cloning and in vivo transformation. In this work, we first characterized methods to protect linear DNA strands from exonuclease degradation in an Escherichia coli based transcription-translation cell-free system (TX-TL), as well as mechanisms of degradation. This enabled the use of linear DNA PCR products in TX-TL. We then compared expression levels and binding dynamics of different promoters on linear DNA and plasmid DNA. We also demonstrated assembly technology to rapidly build circuits entirely in vitro from separate parts. Using this strategy, we prototyped a four component genetic switch in under 8 h entirely in vitro. Rapid in vitro assembly has future applications for prototyping multiple component circuits if combined with predictive computational models.

  15. Rapid prototyping of biodegradable microneedle arrays by integrating CO2 laser processing and polymer molding

    NASA Astrophysics Data System (ADS)

    Tu, K. T.; Chung, C. K.

    2016-06-01

    An integrated technology of CO2 laser processing and polymer molding has been demonstrated for the rapid prototyping of biodegradable poly-lactic-co-glycolic acid (PLGA) microneedle arrays. Rapid and low-cost CO2 laser processing was used for the fabrication of a high-aspect-ratio microneedle master mold instead of conventional time-consuming and expensive photolithography and etching processes. It is crucial to use flexible polydimethylsiloxane (PDMS) to detach PLGA. However, the direct CO2 laser-ablated PDMS could generate poor surfaces with bulges, scorches, re-solidification and shrinkage. Here, we have combined the polymethyl methacrylate (PMMA) ablation and two-step PDMS casting process to form a PDMS female microneedle mold to eliminate the problem of direct ablation. A self-assembled monolayer polyethylene glycol was coated to prevent stiction between the two PDMS layers during the peeling-off step in the PDMS-to-PDMS replication. Then the PLGA microneedle array was successfully released by bending the second-cast PDMS mold with flexibility and hydrophobic property. The depth of the polymer microneedles can range from hundreds of micrometers to millimeters. It is linked to the PMMA pattern profile and can be adjusted by CO2 laser power and scanning speed. The proposed integration process is maskless, simple and low-cost for rapid prototyping with a reusable mold.

  16. The MOLGENIS toolkit: rapid prototyping of biosoftware at the push of a button

    PubMed Central

    2010-01-01

    Background There is a huge demand on bioinformaticians to provide their biologists with user friendly and scalable software infrastructures to capture, exchange, and exploit the unprecedented amounts of new *omics data. We here present MOLGENIS, a generic, open source, software toolkit to quickly produce the bespoke MOLecular GENetics Information Systems needed. Methods The MOLGENIS toolkit provides bioinformaticians with a simple language to model biological data structures and user interfaces. At the push of a button, MOLGENIS’ generator suite automatically translates these models into a feature-rich, ready-to-use web application including database, user interfaces, exchange formats, and scriptable interfaces. Each generator is a template of SQL, JAVA, R, or HTML code that would require much effort to write by hand. This ‘model-driven’ method ensures reuse of best practices and improves quality because the modeling language and generators are shared between all MOLGENIS applications, so that errors are found quickly and improvements are shared easily by a re-generation. A plug-in mechanism ensures that both the generator suite and generated product can be customized just as much as hand-written software. Results In recent years we have successfully evaluated the MOLGENIS toolkit for the rapid prototyping of many types of biomedical applications, including next-generation sequencing, GWAS, QTL, proteomics and biobanking. Writing 500 lines of model XML typically replaces 15,000 lines of hand-written programming code, which allows for quick adaptation if the information system is not yet to the biologist’s satisfaction. Each application generated with MOLGENIS comes with an optimized database back-end, user interfaces for biologists to manage and exploit their data, programming interfaces for bioinformaticians to script analysis tools in R, Java, SOAP, REST/JSON and RDF, a tab-delimited file format to ease upload and exchange of data, and detailed technical

  17. Wine Traceability: A Data Model and Prototype in Albanian Context

    PubMed Central

    Vukatana, Kreshnik; Sevrani, Kozeta; Hoxha, Elira

    2016-01-01

    Vine traceability is a critical issue that has gained interest internationally. Quality control programs and schemes are mandatory in many countries including EU members and the USA. Albania has transformed most of the EU regulations on food into laws. Regarding the vine sector, the obligation of wine producers to keep traceability data is part of the legislation. The analysis on the interviews conducted with Albanian winemakers show that these data are actually recorded only in hard copy. Another fact that emerges from the interviews is that only two producers have implemented the ISO (International Organization for Standardization) standards on food. The purpose of this paper is to develop an agile and automated traceability system based on these standards. We propose a data model and system prototype that are described in the second and third section of this work. The data model is an adaption along the lines of the GS1 (Global Standards One) specifications for a wine supply chain. The proposed prototype has a key component that is mobile access to the information about wine through barcode technology. By using this mechanism the consumer obtains transparency on his expectations concerning the quality criteria. Another important component of the proposed system in this paper is a real-time notification module that works as an alert system when a risk is identified. This can help producers and authorities to have a rapid identification of a contaminated product. It is important in cases when recalling the product from the market or preventing it from reaching the consumer. PMID:28231105

  18. Fabrication of multi-well chips for spheroid cultures and implantable constructs through rapid prototyping techniques.

    PubMed

    Lopa, Silvia; Piraino, Francesco; Kemp, Raymond J; Di Caro, Clelia; Lovati, Arianna B; Di Giancamillo, Alessia; Moroni, Lorenzo; Peretti, Giuseppe M; Rasponi, Marco; Moretti, Matteo

    2015-07-01

    Three-dimensional (3D) culture models are widely used in basic and translational research. In this study, to generate and culture multiple 3D cell spheroids, we exploited laser ablation and replica molding for the fabrication of polydimethylsiloxane (PDMS) multi-well chips, which were validated using articular chondrocytes (ACs). Multi-well ACs spheroids were comparable or superior to standard spheroids, as revealed by glycosaminoglycan and type-II collagen deposition. Moreover, the use of our multi-well chips significantly reduced the operation time for cell seeding and medium refresh. Exploiting a similar approach, we used clinical-grade fibrin to generate implantable multi-well constructs allowing for the precise distribution of multiple cell types. Multi-well fibrin constructs were seeded with ACs generating high cell density regions, as shown by histology and cell fluorescent staining. Multi-well constructs were compared to standard constructs with homogeneously distributed ACs. After 7 days in vitro, expression of SOX9, ACAN, COL2A1, and COMP was increased in both constructs, with multi-well constructs expressing significantly higher levels of chondrogenic genes than standard constructs. After 5 weeks in vivo, we found that despite a dramatic size reduction, the cell distribution pattern was maintained and glycosaminoglycan content per wet weight was significantly increased respect to pre-implantation samples. In conclusion, multi-well chips for the generation and culture of multiple cell spheroids can be fabricated by low-cost rapid prototyping techniques. Furthermore, these techniques can be used to generate implantable constructs with defined architecture and controlled cell distribution, allowing for in vitro and in vivo investigation of cell interactions in a 3D environment. © 2015 Wiley Periodicals, Inc.

  19. New technologies applied to surgical processes: Virtual Reality and rapid prototyping.

    PubMed

    Suárez-Mejías, Cristina; Gomez-Ciriza, Gorka; Valverde, Israel; Parra Calderón, Carlos; Gómez-Cía, Tomás

    2015-01-01

    AYRA is software of virtual reality for training, planning and optimizing surgical procedures. AYRA was developed under a research, development and innovation project financed by the Andalusian Ministry of Health, called VirSSPA. Nowadays AYRA has been successfully used in more than 1160 real cases and after proving its efficiency it has been introduced in the clinical practice at the Virgen del Rocío University Hospital . Furthermore, AYRA allows generating physical 3D biomodels using rapid prototyping technology. They are used for surgical planning support, intraoperative reference or defect reconstruction. In this paper, some of these tools and some real cases are presented.

  20. Rapid prototyping of 2D structures with feature sizes larger than 8 microm.

    PubMed

    Linder, Vincent; Wu, Hongkai; Jiang, Xingyu; Whitesides, George M

    2003-05-15

    This paper extends rapid prototyping for several types of lithography to the 8-25-microm size range, using transparency photomasks prepared by photoplotting. It discusses the technical improvement in photomask quality achieved by photoplotting, compared to the currently used image setting, and demonstrates differences in the resolution that can be obtained with photomasks with features in the 8-100-microm size range. These high-resolution photomasks were used to microfabricate microelectrodes, microlenses, and stamps for microcontact printing, following methods described previously.

  1. [Current progress of fabricating tissue engineering scaffold using rapid prototyping techniques].

    PubMed

    Li, Xiang; Wang, Chengtao

    2008-08-01

    As one of the key factors for tissue engineering, scaffolds affect the spread and proliferation of seeded cells and the formation of new tissue. Although conventional methods can produce porous scaffolds with different porosities, they are lack controls the porous structures of the scaffolds. In recent years, rapid prototyping (RP) techniques have been developed and have successfully applied to fabricate TE scaffolds. RP techniques can provide accurate control over internal pore architectures and complex-shapes. As a result of these techniques, ideal tissue-engineered constructs could be prepared. This paper reviewed the advantages, potential and future directions of RP techniques in the design and fabrication of TE scaffolds.

  2. [The application and advancement of rapid prototyping technology in bone tissue engineering].

    PubMed

    He, Chuanglong; Xia, Liewen; Luo, Yanfeng; Wang, Yuanliang

    2004-10-01

    In bone tissue engineering, a highly porous artificial extracellular matrix or scaffold is essential to the attachment, proliferation and differentiation of bone cells (osteoblast, osteoclast and osteocytes) and the formation of bone tissue. However, conventional scaffold materials for bone tissue engineering proved less valuable for actual applications because they lack mechanical strength, interconnected channel network, and controllable porosity or channel size. Therefore,to explore the ideal scaffold materials is one of the popular studies on current bone tissue engineering. In this paper, we review, the application and advancement of a newly-developed technology generally known as rapid prototyping (RP) techniques in bone tissue engineering.

  3. Using rapid prototyping molds to create patient specific polymethylmethacrylate implants in cranioplasty.

    PubMed

    Gerber, N; Stieglitz, L; Peterhans, M; Nolte, L P; Raabe, A; Weber, S

    2010-01-01

    Cranioplasty is a commonly performed procedure. Outcomes can be improved by the use of patient specific implants, however, high costs limit their accessibility. This paper presents a low cost alternative technique to create patient specific polymethylmethacrylate (PMMA) implants using rapid prototyped mold template. We used available patient's CT-scans, one dataset without craniotomy and one with craniotomy, for computer-assisted design of a 3D mold template, which itself can be brought into the operating room and be used for fast and easy building of a PMMA implant. We applied our solution to three patients with positive outcomes and no complications.

  4. A Rapidly Prototyped Vegetation Dryness Index Evaluated for Wildfire Risk Assessment at Stennis Space Center

    NASA Technical Reports Server (NTRS)

    Ross, Kenton; Graham, William; Prados, Don; Spruce, Joseph

    2007-01-01

    MVDI, which effectively involves the differencing of NDMI and NDVI, appears to display increased noise that is consistent with a differencing technique. This effect masks finer variations in vegetation moisture, preventing MVDI from fulfilling the requirement of giving decision makers insight into spatial variation of fire risk. MVDI shows dependencies on land cover and phenology which also argue against its use as a fire risk proxy in an area of diverse and fragmented land covers. The conclusion of the rapid prototyping effort is that MVDI should not be implemented for SSC decision support.

  5. [Osteogenic activity of porous calcium phosphate ceramics fabricated by rapid prototyping].

    PubMed

    He, Chenguang; Zhao, Li; Lin, Liulan; Gu, Huijie; Zhou, Heng; Cui, Lei

    2010-07-01

    Calcium phosphate bioceramics has a broad application prospect because of good biocompatibility, but porous scaffolds with complex shape can not be prepared by the traditional methods. To fabricate porous calcium phosphate ceramics by rapid prototyping and to investigate the in vitro osteogenic activities. The porous calcium phosphate ceramics was fabricated by rapid prototyping. The bone marrow mesenchymal stem cells (BMSCs) were isolated from bone marrow of Beagle canine, and the 3rd passage BMSCs were seeded onto the porous ceramics. The cell/ceramics composite cultured in osteogenic medium were taken as the experimental group (group A) and the cell/ceramics composite cultured in growth medium were taken as the control group (group B). Meanwhile, the cells seeded on the culture plate were cultured in osteogenic medium or growth medium respectively as positive control (group C) or negative control (group D). After 1, 3, and 7 days of culture, the cell proliferation and osteogenic differentiation on the porous ceramics were evaluated by DNA quantitative analysis, histochemical staining and alkaline phosphatase (ALP) activity. After DiO fluorescent dye, the cell adhesion, growth, and proliferation on the porous ceramics were also observed by confocal laser scanning microscope (CLSM). DNA quantitative analysis results showed that the number of BMSCs in all groups increased continuously with time. Plateau phase was not obvious in groups A and B, but it was clearly observed in groups C and D. The CLSM observation indicated that the activity of BMSCs was good and the cells spread extensively, showing good adhesion and proliferation on the porous calcium phosphate ceramics prepared by rapid prototyping. ALP quantitative analysis results showed that the stain of cells on the ceramics became deeper and deeper with time in groups A and B, the staining degree in group A were stronger than that in group B. There was no significant difference in the change of the ALP activity

  6. Rapid tooling for functional prototyping of metal mold processes: Literature review on cast tooling

    SciTech Connect

    Baldwin, M.D.; Hochanadel, P.W.

    1995-11-01

    This report is a literature review on cast tooling with the general focus on AISI H13 tool steel. The review includes processing of both wrought and cast H13 steel along with the accompanying microstructures. Also included is the incorporation of new rapid prototyping technologies, such as Stereolithography and Selective Laser Sintering, into the investment casting of tool steel. The limiting property of using wrought or cast tool steel for die casting is heat checking. Heat checking is addressed in terms of testing procedures, theories regarding the mechanism, and microstructural aspects related to the cracking.

  7. Mirror-image anterior crown fabrication with computer-aided design and rapid prototyping technology: a clinical report.

    PubMed

    Cho, Seok-Hwan; Chang, Won-Gun

    2013-02-01

    This clinical report describes the fabrication of a maxillary central incisor single crown with rapid prototyping (RP) technology. A patient with a recently replaced metal ceramic crown had discomfort due to the nonanatomic lingual contour of the crown. With computer-aided design (CAD) software and rapid prototyping (RP) technology, the shape of the contralateral central incisor was duplicated and reproduced to make a mirror-image for a new crown. The prosthodontic planning and treatment approach are discussed.

  8. Risk reduction on the CrIS program through rapid prototyping

    NASA Astrophysics Data System (ADS)

    Webb, Merritt; Hookman, Robert A.

    2002-02-01

    The Crosstrack Infrared Sounder (CrIS) is one of the sensors now under development for the National Polar-orbiting Operational Environmental Satellite System (NPOESS) program. In order to reduce program risk and verify instrument performance on the CrIS Program, various independent research projects were integrated into a prototype instrument. This was a rapid prototype built in 6 months that was similar to flight in the significant risk areas. This prototype instrument is referred to as the EDU1 (Engineering Development Unit). The coordination between the various, previously disjointed research tasks was a critical part of the effort. A layout of the flight CrIS instrument was the departure point for this effort. This layout was used to establish interfaces between the various modules. A set of clear cardinal requirements was established. The layout and the cardinal requirements therefore provided a conceptual overview and a basis for deriving lower level requirements. These requirements remained basically unchanged throughout the effort. The purpose of this paper is to describe the CrIS EDU1 system design and build, and summarize the key performance capabilities of the EDU1.

  9. The Role of Prototype Learning in Hierarchical Models of Vision

    ERIC Educational Resources Information Center

    Thomure, Michael David

    2014-01-01

    I conduct a study of learning in HMAX-like models, which are hierarchical models of visual processing in biological vision systems. Such models compute a new representation for an image based on the similarity of image sub-parts to a number of specific patterns, called prototypes. Despite being a central piece of the overall model, the issue of…

  10. The Role of Prototype Learning in Hierarchical Models of Vision

    ERIC Educational Resources Information Center

    Thomure, Michael David

    2014-01-01

    I conduct a study of learning in HMAX-like models, which are hierarchical models of visual processing in biological vision systems. Such models compute a new representation for an image based on the similarity of image sub-parts to a number of specific patterns, called prototypes. Despite being a central piece of the overall model, the issue of…

  11. Interactive visual steering--rapid visual prototyping of a common rail injection system.

    PubMed

    Matković, Kresimir; Gracanin, Denis; Jelović, Mario; Hauser, Helwig

    2008-01-01

    Interactive steering with visualization has been a common goal of the visualization research community for twenty years, but it is rarely ever realized in practice. In this paper we describe a successful realization of a tightly coupled steering loop, integrating new simulation technology and interactive visual analysis in a prototyping environment for automotive industry system design. Due to increasing pressure on car manufacturers to meet new emission regulations, to improve efficiency, and to reduce noise, both simulation and visualization are pushed to their limits. Automotive system components, such as the powertrain system or the injection system have an increasing number of parameters, and new design approaches are required. It is no longer possible to optimize such a system solely based on experience or forward optimization. By coupling interactive visualization with the simulation back-end (computational steering), it is now possible to quickly prototype a new system, starting from a non-optimized initial prototype and the corresponding simulation model. The prototyping continues through the refinement of the simulation model, of the simulation parameters and through trial-and-error attempts to an optimized solution. The ability to early see the first results from a multidimensional simulation space--thousands of simulations are run for a multidimensional variety of input parameters--and to quickly go back into the simulation and request more runs in particular parameter regions of interest significantly improves the prototyping process and provides a deeper understanding of the system behavior. The excellent results which we achieved for the common rail injection system strongly suggest that our approach has a great potential of being generalized to other, similar scenarios.

  12. Accuracy of using computer-aided rapid prototyping templates for mandible reconstruction with an iliac crest graft.

    PubMed

    Shu, Da-long; Liu, Xiang-zhen; Guo, Bing; Ran, Wei; Liao, Xin; Zhang, Yun-yan

    2014-06-24

    This study aimed to evaluate the accuracy of surgical outcomes in free iliac crest mandibular reconstructions that were carried out with virtual surgical plans and rapid prototyping templates. This study evaluated eight patients who underwent mandibular osteotomy and reconstruction with free iliac crest grafts using virtual surgical planning and designed guiding templates. Operations were performed using the prefabricated guiding templates. Postoperative three-dimensional computer models were overlaid and compared with the preoperatively designed models in the same coordinate system. Compared to the virtual osteotomy, the mean error of distance of the actual mandibular osteotomy was 2.06 ± 0.86 mm. When compared to the virtual harvested grafts, the mean error volume of the actual harvested grafts was 1412.22 ± 439.24 mm3 (9.12% ± 2.84%). The mean error between the volume of the actual harvested grafts and the shaped grafts was 2094.35 ± 929.12 mm3 (12.40% ± 5.50%). The use of computer-aided rapid prototyping templates for virtual surgical planning appears to positively influence the accuracy of mandibular reconstruction.

  13. Accuracy of using computer-aided rapid prototyping templates for mandible reconstruction with an iliac crest graft

    PubMed Central

    2014-01-01

    Background This study aimed to evaluate the accuracy of surgical outcomes in free iliac crest mandibular reconstructions that were carried out with virtual surgical plans and rapid prototyping templates. Methods This study evaluated eight patients who underwent mandibular osteotomy and reconstruction with free iliac crest grafts using virtual surgical planning and designed guiding templates. Operations were performed using the prefabricated guiding templates. Postoperative three-dimensional computer models were overlaid and compared with the preoperatively designed models in the same coordinate system. Results Compared to the virtual osteotomy, the mean error of distance of the actual mandibular osteotomy was 2.06 ± 0.86 mm. When compared to the virtual harvested grafts, the mean error volume of the actual harvested grafts was 1412.22 ± 439.24 mm3 (9.12% ± 2.84%). The mean error between the volume of the actual harvested grafts and the shaped grafts was 2094.35 ± 929.12 mm3 (12.40% ± 5.50%). Conclusions The use of computer-aided rapid prototyping templates for virtual surgical planning appears to positively influence the accuracy of mandibular reconstruction. PMID:24957053

  14. Design and manufacturing of ear prosthesis by means of rapid prototyping technology.

    PubMed

    De Crescenzio, F; Fantini, M; Ciocca, L; Persiani, F; Scotti, R

    2011-03-01

    In this paper, the complete procedure to design and construct reusable moulds for implant-based ear prosthesis and manufacture substructures by means of a computer aided design-computer aided manufacturing (CAD-CAM) procedure and rapid prototyping (RP) technology is presented. The scan of the healthy ear, the virtual superimposition of its mirrored image on to the defective side, and the rapid manufacturing of the substructure and of the mould eliminate several steps of traditional procedures (wax, stone, try-in). Moreover, the precise design and customization of the substructure is presented, with the original and engineered shape for the retention of the silicone. The time and cost saving results of this protocol are presented together with a discussion of the main design features that make the prosthesis a stable and reproducible system to improve rehabilitation of patients with auricular defects or absence.

  15. Three-Dimensional Rapid Prototyping of Multidirectional Polymer Nanoprobes for Single Cell Insertion.

    PubMed

    Yang, Dasom; Hong, Hyeonaug; Seo, Yoon Ho; Kim, Lo Hyun; Ryu, WonHyoung

    2015-08-05

    Three-dimensional (3D) thermal drawing at nanoscale as a novel rapid prototyping method was demonstrated to create multidirectional polymer nanoprobes for single cell analysis. This 3D drawing enables simple and rapid fabrication of polymeric nanostructures with high aspect ratio. The effect of thermal drawing parameters, such as drawing speeds, dipping depths, and contact duration on the final geometry of polymer nanostructures was investigated. Vertically aligned and L-shaped nanoprobes were fabricated and their insertion into living single cells such as algal cells and human neural stem cells was demonstrated. This technique can be extended to create more complex 3D structures by controlling drawing steps and directions on any surface.

  16. Effects of Hydrocarbon-Based Grease on Rapid Prototype Material Used for Grease Retention Shrouds

    NASA Technical Reports Server (NTRS)

    Zakrajsek, Andrew J.; Valco, Daniel J.; Street, Kenneth W., Jr.

    2010-01-01

    Effects of hydrocarbon-based greases on specific rapid prototype (RP) materials used to fabricate grease retention shrouds (GRS) were explored in this study. Grease retention shrouds are being considered as a way to maintain adequate grease lubrication at the gear mesh in a prototype research transmission system. Due to their design and manufacturing flexibility, rapid prototype materials were chosen for the grease retention shrouds. In order to gain a better understanding of the short and long term effects grease pose on RP materials, research was conducted on the interaction of hydrocarbon-based grease with RP materials. The materials used in this study were durable polyamide (nylon), acrylonitrile butadiene styrene (ABS), and WaterClear 10120. Testing was conducted using Mobilgrease 28 and Syn-Tech 3913G grease (gear coupling grease). These greases were selected due to their regular use with mechanical components. To investigate the effect that grease has on RP materials, the following methods were used to obtain qualitative and quantitative data: Fourier transform infrared spectroscopy (FT-IR), interference profilometer measurements, digital camera imaging, physical shape measurement, and visual observations. To record the changes in the RP materials due to contact with the grease, data was taken before and after the grease application. Results showed that the WaterClear 10120 RP material provided the best resistance to grease penetration as compared to nylon and ABS RP materials. The manufacturing process, and thus resulting surface conditions of the RP material, played a key role in the grease penetration properties and resilience of these materials.

  17. A new UV-curing elastomeric substrate for rapid prototyping of microfluidic devices

    NASA Astrophysics Data System (ADS)

    Alvankarian, Jafar; Yeop Majlis, Burhanuddin

    2012-03-01

    Rapid prototyping in the design cycle of new microfluidic devices is very important for shortening time-to-market. Researchers are facing the challenge to explore new and suitable substrates with simple and efficient microfabrication techniques. In this paper, we introduce and characterize a UV-curing elastomeric polyurethane methacrylate (PUMA) for rapid prototyping of microfluidic devices. The swelling and solubility of PUMA in different chemicals is determined. Time-dependent measurements of water contact angle show that the native PUMA is hydrophilic without surface treatment. The current monitoring method is used for measurement of the electroosmotic flow mobility in the microchannels made from PUMA. The optical, physical, thermal and mechanical properties of PUMA are evaluated. The UV-lithography and molding process is used for making micropillars and deep channel microfluidic structures integrated to the supporting base layer. Spin coating is characterized for producing different layer thicknesses of PUMA resin. A device is fabricated and tested for examining the strength of different bonding techniques such as conformal, corona treating and semi-curing of two PUMA layers in microfluidic application and the results show that the bonding strengths are comparable to that of PDMS. We also report fabrication and testing of a three-layer multi inlet/outlet microfluidic device including a very effective fluidic interconnect for application demonstration of PUMA as a promising new substrate. A simple micro-device is developed and employed for observing the pressure deflection of membrane made from PUMA as a very effective elastomeric valve in microfluidic devices.

  18. Development of novel hybrid poly(L-lactide)/chitosan scaffolds using the rapid freeze prototyping technique.

    PubMed

    Zhu, N; Li, M G; Cooper, D; Chen, X B

    2011-09-01

    Engineered scaffolds have been shown to be critical to various tissue engineering applications. This paper presents the development of a novel three-dimensional scaffold made from a mixture of chitosan microspheres (CMs) and poly(L-lactide) by means of the rapid freeze prototyping (RFP) technique. The CMs were used to encapsulate bovine serum albumin (BSA) and improve the scaffold mechanical properties. Experiments to examine the BSA release were carried out; the BSA release could be controlled by adjusting the crosslink degree of the CMs and prolonged after the CMs were embedded into the PLLA scaffolds, while the examination of the mechanical properties of the scaffolds illustrates that they depend on the ratio of CMs to PLLA in the scaffolds as well as the cryogenic temperature used in the RFP fabrication process. The chemical characteristics of the PLLA/chitosan scaffolds were evaluated by Fourier transform infrared (FTIR) spectroscopy. The morphological and pore structure of the scaffolds were also examined by scanning electron microscopy and micro-tomography. The results obtained show that the scaffolds have higher porosity and enhanced pore size distribution compared to those fabricated by the dispensing-based rapid prototyping technique. This study demonstrates that the novel scaffolds have not only enhanced porous structure and mechanical properties but also showed the potential to preserve the bioactivities of the biomolecules and to control the biomolecule distribution and release rate.

  19. Gene-modified stem cells combined with rapid prototyping techniques: a novel strategy for periodontal regeneration.

    PubMed

    He, Huixia; Cao, Junkai; Wang, Dongsheng; Gu, Bing; Guo, Hong; Liu, Hongchen

    2010-03-01

    Periodontal disease, a worldwide prevalent chronic disease in adults, is characterized by the destruction of the periodontal supporting tissue including the cementum, periodontal ligament and alveolar bone. The regeneration of damaged periodontal tissue is the main goal of periodontal treatment. Because conventional periodontal treatments remain insufficient to attain complete and reliable periodontal regeneration, periodontal tissue engineering has emerged as a prospective alternative method for improving the regenerative capacity of periodontal tissue. However, the potential of periodontal regeneration seems to be limited by the understanding of the cellular and molecular events in the formation of periodontal tissue and by the insufficient collaboration of multi-disciplinary research that periodontal tissue engineering involves. In this paper, we first reviewed the recent advancements in stem cells, signaling factors, and scaffolds that relate to periodontal regeneration. Then we speculate that specific genes would improve regenerative capacity of these stem cells, which could differentiate into cementoblasts, osteoblasts and fibroblasts. In addition, the 3D scaffolds that mimic the different structure and physiologic functions of natural fibro-osseous tissue could be fabricated by rapid prototyping (RP) techniques. It was therefore hypothesized that gene-modified stem cells combined with rapid prototyping techniques would be a new strategy to promote more effective and efficient periodontal regeneration.

  20. The Java Image Science Toolkit (JIST) for rapid prototyping and publishing of neuroimaging software.

    PubMed

    Lucas, Blake C; Bogovic, John A; Carass, Aaron; Bazin, Pierre-Louis; Prince, Jerry L; Pham, Dzung L; Landman, Bennett A

    2010-03-01

    Non-invasive neuroimaging techniques enable extraordinarily sensitive and specific in vivo study of the structure, functional response and connectivity of biological mechanisms. With these advanced methods comes a heavy reliance on computer-based processing, analysis and interpretation. While the neuroimaging community has produced many excellent academic and commercial tool packages, new tools are often required to interpret new modalities and paradigms. Developing custom tools and ensuring interoperability with existing tools is a significant hurdle. To address these limitations, we present a new framework for algorithm development that implicitly ensures tool interoperability, generates graphical user interfaces, provides advanced batch processing tools, and, most importantly, requires minimal additional programming or computational overhead. Java-based rapid prototyping with this system is an efficient and practical approach to evaluate new algorithms since the proposed system ensures that rapidly constructed prototypes are actually fully-functional processing modules with support for multiple GUI's, a broad range of file formats, and distributed computation. Herein, we demonstrate MRI image processing with the proposed system for cortical surface extraction in large cross-sectional cohorts, provide a system for fully automated diffusion tensor image analysis, and illustrate how the system can be used as a simulation framework for the development of a new image analysis method. The system is released as open source under the Lesser GNU Public License (LGPL) through the Neuroimaging Informatics Tools and Resources Clearinghouse (NITRC).

  1. Fastcast: Integration and application of rapid prototyping and computational simulation to investment casting

    SciTech Connect

    Maguire, M.C.; Baldwin, M.D.; Atwood, C.L.

    1996-09-01

    The emergence of several rapid prototyping and manufacturing (RP and M) technologies is having a dramatic impact on investment casting. While the most successful of the rapid prototyping technologies are almost a decade old, relatively recent process advances in their application have produced some remarkable success in utilizing their products as patterns for investment castings. Sandia National Laboratories has been developed highly coupled experimental and computational capabilities to examine the investment casting process with the intention of reducing the amount of time required to manufacture castings, and to increase the quality of the finished product. This presentation will begin with process aspects of RP and M pattern production and handling, shell fabrication, burnout, and casting. The emphasis will be on how the use of Stereolithography (SL) or Selective Laser Sintered (SLS) patterns differs from more traditional wax pattern processes. Aspects of computational simulation to couple design, thermal analysis, and mold filling will be discussed. Integration of these topics is probably the greatest challenge to the use of concurrent engineering principles with investment casting. Sandia has conducted several experiments aimed at calibrating computer codes and providing data for input into these simulations. Studies involving materials as diverse as stainless steel and gold have been conducted to determine liquid metal behavior in molds via real time radiography. The application of these experiments to predictive simulations will be described.

  2. Fabrication of thermoset polyester microfluidic devices and embossing masters using rapid prototyped polydimethylsiloxane molds.

    PubMed

    Fiorini, Gina S; Jeffries, Gavin D M; Lim, David S W; Kuyper, Christopher L; Chiu, Daniel T

    2003-08-01

    Plastics are increasingly being used for the fabrication of Lab-on-a-Chip devices due to the variety of beneficial material properties, affordable cost, and straightforward fabrication methods available from a range of different types of plastics. Rapid prototyping of polydimethylsiloxane (PDMS) devices has become a well-known process for the quick and easy fabrication of microfluidic devices in the research laboratory; however, PDMS is not always an appropriate material for every application. This paper describes the fabrication of thermoset polyester microfluidic devices and masters for hot embossing using replica molding techniques. Rapid prototyped PDMS molds are convienently used for the production of non-PDMS polymeric devices. The recessed features in the cast polyester can be bonded to a second polyester piece to form an enclosed microchannel. Thermoset polyester can withstand moderate amounts of pressure and elevated temperature; therefore, the cast polyester piece also can be used as a master for embossing polymethylmethacrylate (PMMA) microfluidic systems. Examples of enclosed polyester and PMMA microchannels are presented, and we discuss the electroosmotic properties of both types of channels, which are important for analytical applications such as capillary electrophoresis.

  3. A yeast-based rapid prototype platform for gene control elements in mammalian cells.

    PubMed

    Wei, Kathy Y; Chen, Yvonne Y; Smolke, Christina D

    2013-04-01

    Programming genetic circuits in mammalian cells requires flexible, tunable, and user-tailored gene-control systems. However, most existing control systems are either mechanistically specific for microbial organisms or must be laboriously re-engineered to function in mammalian cells. Here, we demonstrate a ribozyme-based device platform that can be directly transported from yeast to mammalian cells in a "plug-and-play" manner. Ribozyme switches previously prototyped in yeast are shown to regulate gene expression in a predictable, ligand-responsive manner in human HEK 293, HeLa, and U2OS cell lines without any change to device sequence nor further optimization. The ribozyme-based devices, which exhibit activation ratios comparable to the best RNA-based regulatory devices demonstrated in mammalian cells to-date, retain their prescribed functions (ON or OFF switch), tunability of regulatory stringency, and responsiveness to different small-molecule inputs in mammalian hosts. Furthermore, we observe strong correlations of device performance between yeast and all mammalian cell lines tested (R(2)  = 0.63-0.97). Our unique device architecture can therefore act as a rapid prototyping platform (RPP) based on a yeast chassis, providing a well-developed and genetically tractable system that supports rapid and high-throughput screens for generating gene-controllers with a broad range of functions in mammalian cells. This platform will accelerate development of mammalian gene-controllers for diverse applications, including cell-based therapeutics and cell-fate reprogramming.

  4. Rapid prototyping of microfluidic systems using a PDMS/polymer tape composite.

    PubMed

    Kim, Jungkyu; Surapaneni, Rajesh; Gale, Bruce K

    2009-05-07

    Rapid prototyping of microfluidic systems using a combination of double-sided tape and PDMS (polydimethylsiloxane) is introduced. PDMS is typically difficult to bond using adhesive tapes due to its hydrophobic nature and low surface energy. For this reason, PDMS is not compatible with the xurography method, which uses a knife plotter and various adhesive coated polymer tapes. To solve these problems, a PDMS/tape composite was developed and demonstrated in microfluidic applications. The PDMS/tape composite was created by spinning it to make a thin layer of PDMS over double-sided tape. Then the PDMS/tape composite was patterned to create channels using xurography, and bonded to a PDMS slab. After removing the backing paper from the tape, a complete microfluidic system could be created by placing the construct onto nearly any substrate; including glass, plastic or metal-coated glass/silicon substrates. The bond strength was shown to be sufficient for the pressures that occur in typical microfluidic channels used for chemical or biological analysis. This method was demonstrated in three applications: standard microfluidic channels and reactors, a microfluidic system with an integrated membrane, and an electrochemical biosensor. The PDMS/tape composite rapid prototyping technique provides a fast and cost effective fabrication method and can provide easy integration of microfluidic channels with sensors and other components without the need for a cleanroom facility.

  5. The Java Image Science Toolkit (JIST) for Rapid Prototyping and Publishing of Neuroimaging Software

    PubMed Central

    Lucas, Blake C.; Bogovic, John A.; Carass, Aaron; Bazin, Pierre-Louis; Prince, Jerry L.; Pham, Dzung

    2010-01-01

    Non-invasive neuroimaging techniques enable extraordinarily sensitive and specific in vivo study of the structure, functional response and connectivity of biological mechanisms. With these advanced methods comes a heavy reliance on computer-based processing, analysis and interpretation. While the neuroimaging community has produced many excellent academic and commercial tool packages, new tools are often required to interpret new modalities and paradigms. Developing custom tools and ensuring interoperability with existing tools is a significant hurdle. To address these limitations, we present a new framework for algorithm development that implicitly ensures tool interoperability, generates graphical user interfaces, provides advanced batch processing tools, and, most importantly, requires minimal additional programming or computational overhead. Java-based rapid prototyping with this system is an efficient and practical approach to evaluate new algorithms since the proposed system ensures that rapidly constructed prototypes are actually fully-functional processing modules with support for multiple GUI's, a broad range of file formats, and distributed computation. Herein, we demonstrate MRI image processing with the proposed system for cortical surface extraction in large cross-sectional cohorts, provide a system for fully automated diffusion tensor image analysis, and illustrate how the system can be used as a simulation framework for the development of a new image analysis method. The system is released as open source under the Lesser GNU Public License (LGPL) through the Neuroimaging Informatics Tools and Resources Clearinghouse (NITRC). PMID:20077162

  6. Indirect Rapid Prototyping: Opening Up Unprecedented Opportunities in Scaffold Design and Applications.

    PubMed

    Houben, Annemie; Van Hoorick, Jasper; Van Erps, Jürgen; Thienpont, Hugo; Van Vlierberghe, Sandra; Dubruel, Peter

    2017-01-01

    Over the past decades, solid freeform fabrication (SFF) has emerged as the main technology for the production of scaffolds for tissue engineering applications as a result of the architectural versatility. However, certain limitations have also arisen, primarily associated with the available, rather limited range of materials suitable for processing. To overcome these limitations, several research groups have been exploring novel methodologies through which a construct, generated via SFF, is applied as a sacrificial mould for production of the final construct. The technique combines the benefits of SFF techniques in terms of controlled, patient-specific design with a large freedom in material selection associated with conventional scaffold production techniques. Consequently, well-defined 3D scaffolds can be generated in a straightforward manner from previously difficult to print and even "unprintable" materials due to thermomechanical properties that do not match the often strict temperature and pressure requirements for direct rapid prototyping. These include several biomaterials, thermally degradable materials, ceramics and composites. Since it can be combined with conventional pore forming techniques, indirect rapid prototyping (iRP) enables the creation of a hierarchical porosity in the final scaffold with micropores inside the struts. Consequently, scaffolds and implants for applications in both soft and hard tissue regeneration have been reported. In this review, an overview of different iRP strategies and materials are presented from the first reports of the approach at the turn of the century until now.

  7. A Hybrid Tool for User Interface Modeling and Prototyping

    NASA Astrophysics Data System (ADS)

    Trætteberg, Hallvard

    Although many methods have been proposed, model-based development methods have only to some extent been adopted for UI design. In particular, they are not easy to combine with user-centered design methods. In this paper, we present a hybrid UI modeling and GUI prototyping tool, which is designed to fit better with IS development and UI design traditions. The tool includes a diagram editor for domain and UI models and an execution engine that integrates UI behavior, live UI components and sample data. Thus, both model-based user interface design and prototyping-based iterative design are supported

  8. A prototypic mathematical model of the human hair cycle.

    PubMed

    Al-Nuaimi, Yusur; Goodfellow, Marc; Paus, Ralf; Baier, Gerold

    2012-10-07

    The human hair cycle is a complex, dynamic organ-transformation process during which the hair follicle repetitively progresses from a growth phase (anagen) to a rapid apoptosis-driven involution (catagen) and finally a relative quiescent phase (telogen) before returning to anagen. At present no theory satisfactorily explains the origin of the hair cycle rhythm. Based on experimental evidence we propose a prototypic model that focuses on the dynamics of hair matrix keratinocytes. We argue that a plausible feedback-control structure between two key compartments (matrix keratinocytes and dermal papilla) leads to dynamic instabilities in the population dynamics resulting in rhythmic hair growth. The underlying oscillation consists of an autonomous switching between two quasi-steady states. Additional features of the model, namely bistability and excitability, lead to new hypotheses about the impact of interventions on hair growth. We show how in silico testing may facilitate testing of candidate hair growth modulatory agents in human HF organ culture or in clinical trials. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Rapid prototyping to design a customized locking plate for pancarpal arthrodesis in a giant breed dog.

    PubMed

    Petazzoni, M; Nicetto, T

    2014-01-01

    This report describes the treatment of traumatic carpal hyperextension in a giant breed dog by pancarpal arthrodesis using a custom-made Fixin locking plate, created with the aid of a three-dimensional plastic model of the bones of the antebrachium produced by rapid prototyping technology. A three-year-old 104 kg male Mastiff dog was admitted for treatment of carpal hyperextension injury. After diagnosis of carpal instability, surgery was recommended. Computed tomography images were used to create a life-size three-dimensional plastic model of the forelimb. The model was used as the basis for constructing a customized 12-hole Fixin locking plate. The plate was used to attain successful pancarpal arthrodesis in the animal. Radiographic examination after 74 and 140 days revealed signs of osseous union of the arthrodesis. Further clinical and radiographic follow-up examination three years later did not reveal any changes in implant position or complications.

  10. A new production method of elastic silicone carotid phantom based on MRI acquisition using rapid prototyping technique.

    PubMed

    Cao, Peng; Duhamel, Yvan; Olympe, Guillaume; Ramond, Bruno; Langevin, Francois

    2013-01-01

    In vitro experimental simulations of blood fluid in carotid artery require ideal phantoms that are as precise as possible. The purpose of this work is to demonstrate a method for carotid phantom fabrication by rapid prototyping technique (RP). By using 3D reconstructed projection of the 3D time-of-flight (TOF) Magnetic Resonance Imaging (MRI) sequence, a 12.5 cm multi-dimensional spatial structure of a carotid artery has been set up. Y-shaped and patient specific models have been generated respectively using silicone elastomer, which has a high resilience and a good tensile strength. The final patient specific model has internal carotid artery (ICA) with a highly spiraling siphon and an external carotid artery (ECA). Elastic properties of carotid walls have also been evaluated by Young's elastic modulus test and dynamic behaviors in optical and echography simulation experiments.

  11. SAMM: a prototype southeast Alaska multiresource model.

    Treesearch

    Roger D. Fight; Lawrence D. Garrett; Dale L. Weyermann

    1990-01-01

    The adaptive environmental assessment method was used by an interdisciplinary team of forest specialists to gain an understanding of resource interactions and tradeoffs resulting from forest management activities in southeast Alaska. A forest multiresource projection model was developed in the process. The multiresource model, “SAMM,” is capable of characterizing and...

  12. FLASH: A rapid method for prototyping paper-based microfluidic devices‡

    PubMed Central

    Martinez, Andres W.; Phillips, Scott T.; Wiley, Benjamin J.; Gupta, Malancha

    2011-01-01

    This article describes FLASH (Fast Lithographic Activation of Sheets), a rapid method for laboratory prototyping of microfluidic devices in paper. Paper-based microfluidic devices are emerging as a new technology for applications in diagnostics for the developing world, where low cost and simplicity are essential. FLASH is based on photolithography, but requires only a UV lamp and a hotplate; no clean-room or special facilities are required (FLASH patterning can even be performed in sunlight if a UV lamp and hotplate are unavailable). The method provides channels in paper with dimensions as small as 200 μm in width and 70 μm in height; the height is defined by the thickness of the paper. Photomasks for patterning paper-based microfluidic devices can be printed using an ink-jet printer or photocopier, or drawn by hand using a waterproof black pen. FLASH provides a straightforward method for prototyping paper-based microfluidic devices in regions where the technological support for conventional photolithography is not available. PMID:19023478

  13. FLASH: a rapid method for prototyping paper-based microfluidic devices.

    PubMed

    Martinez, Andres W; Phillips, Scott T; Wiley, Benjamin J; Gupta, Malancha; Whitesides, George M

    2008-12-01

    This article describes FLASH (Fast Lithographic Activation of Sheets), a rapid method for laboratory prototyping of microfluidic devices in paper. Paper-based microfluidic devices are emerging as a new technology for applications in diagnostics for the developing world, where low cost and simplicity are essential. FLASH is based on photolithography, but requires only a UV lamp and a hotplate; no clean-room or special facilities are required (FLASH patterning can even be performed in sunlight if a UV lamp and hotplate are unavailable). The method provides channels in paper with dimensions as small as 200 microm in width and 70 microm in height; the height is defined by the thickness of the paper. Photomasks for patterning paper-based microfluidic devices can be printed using an ink-jet printer or photocopier, or drawn by hand using a waterproof black pen. FLASH provides a straightforward method for prototyping paper-based microfluidic devices in regions where the technological support for conventional photolithography is not available.

  14. [Application of computer aided design and rapid prototyping technology for defected maxilla restoration].

    PubMed

    Tong, Dai; Feng, Hai-lan; Li, Yan-sheng; Zhou, Zhi-bo

    2007-06-01

    To test a new cast-making method based on computer aided design (CAD) and rapid prototyping (RP) technology for defected maxilla. Head CT data of 12 patients with defected maxilla were transmitted into a computer. Three-dimensional digital image of the patient's defected maxilla was then obtained based on Mimics 8.11 and Geomagic 7.0 and the plastic cast of the defected region was manufactured by prototyping. The obturator was made on this plastic cast that duplicated the undercut tissue of defected area. The prominent part of the obturator was made of elastic heat-curing resin and it was helpful to gain the retention through the engagement between the obturator and the tissue undercut. After the obturator was finished, the upper removable partial denture was fabricated in conventional method. The combination of these two parts was achieved using magnetic attachment. Clinical effects of obturator and removable partial denture were evaluated and the nasalance value of 5 patients before and after insertion of the obturator was measured using nanometer. The obturator and removable partial denture could be seated into place separately. They all had good retention and stability. After the obturator was seated in place, the nasalance of non-nasal and vowel text decreased from (46.53 +/- 13.86)% to (22.60 +/- 8.52)% (P < 0.001). The cast-making method based on CAD and RP technology for cast-making of defected maxilla is feasible and practical.

  15. The application of rapid prototyping to improve bone reconstruction in immediate dentoalveolar restoration: a case report.

    PubMed

    Martins da Rosa, José Carlos; Fadanelli, Marcos Alexandre; Zimmerman, Diego; de Oliveira Rosa, Ariádene Cristina Pértile

    This article describes the use of rapid prototyping (RP) for diagnosis, planning, and execution of the reconstruction of hard and soft tissue in socket defects using immediate dentoalveolar restoration (IDR). In cases of tissue loss in anterior dental areas, esthetic rehabilitation poses a major challenge with respect to treatment planning with the goal of long-term tissue maintenance. The IDR technique consists of immediate reconstruction in a single procedure of bone and soft tissue around implants placed immediately after extraction, and prosthetic rehabilitation. As this procedure is immediate and flapless, the correct diagnosis of tissue loss and correct graft adaptation are mandatory. RP can increase the precision of the procedure, as demonstrated using a clinical case characterized by total loss of the buccal bone wall and gingival recession. The results were evaluated by clinical assessment, photography, radiography, cone beam computed tomography (CBCT), and prototyping. The application of RP facilitated the execution of IDR as it enabled more accurate diagnosis of the socket defect and more precise adaptation of the tissue graft. A clinical study should be conducted to evaluate the effects of RP on the clinical results of the IDR technique.

  16. Development of a prototype immunochromatographic test for rapid diagnosis of respiratory adenovirus infection.

    PubMed

    Paulini, Inarei; Siqueira-Silva, Joselma; Thomaz, Luciana; Rocha, Leticia; Harsi, Charlotte; Bellei, Nancy; Granato, Celso

    Human adenoviruses comprise an important group of etiologic agents that are responsible for various diseases in adults and children, such as respiratory, ocular, gastroenteric, and urinary infections. In immunocompromised and organ-transplanted individuals, these agents can cause generalized infections. Rapid diagnostic methods for detecting these infectious agents are not widely available. The aim of this work was to produce monoclonal and polyclonal anti-adenovirus antibodies to be used in a rapid diagnostic test for respiratory infections. Adenovirus hexons were satisfactorily purified by ultracentrifugation and chromatography. After virus purification, anti-hexon monoclonal antibodies were produced and characterized, following classical methods. Antibodies were specific for adenoviruses 2, 3, 5, and 41. The proposed immunochromatographic test was standardized using colloidal gold. The standardization of the rapid test was sufficient to detect adenovirus antigens (in nasopharyngeal lavage samples) with sensitivity of 100% and specificity of 85% when compared to direct immunofluorescence. The immunochromatographic assay prototype was sufficiently sensitive to detect B (3), C (2 and 5), and F (41) adenovirus samples. Although based on preliminary data, the test demonstrated the same performance as direct immunofluorescence, but with the advantage of being a point-of-care test. Further studies are still needed to confirm its effectiveness in clinical practice. Copyright © 2017 Sociedade Brasileira de Infectologia. Published by Elsevier Editora Ltda. All rights reserved.

  17. A system for rapid prototyping of hearts with congenital malformations based on the medical imaging interaction toolkit (MITK)

    NASA Astrophysics Data System (ADS)

    Wolf, Ivo; Böttger, Thomas; Rietdorf, Urte; Maleike, Daniel; Greil, Gerald; Sieverding, Ludger; Miller, Stephan; Mottl-Link, Sibylle; Meinzer, Hans-Peter

    2006-03-01

    Precise knowledge of the individual cardiac anatomy is essential for diagnosis and treatment of congenital heart disease. Complex malformations of the heart can best be comprehended not from images but from anatomic specimens. Physical models can be created from data using rapid prototyping techniques, e.g., lasersintering or 3D-printing. We have developed a system for obtaining data that show the relevant cardiac anatomy from high-resolution CT/MR images and are suitable for rapid prototyping. The challenge is to preserve all relevant details unaltered in the produced models. The main anatomical structures of interest are the four heart cavities (atria, ventricles), the valves and the septum separating the cavities, and the great vessels. These can be shown either by reproducing the morphology itself or by producing a model of the blood-pool, thus creating a negative of the morphology. Algorithmically the key issue is segmentation. Practically, possibilities allowing the cardiologist or cardiac surgeon to interactively check and correct the segmentation are even more important due to the complex, irregular anatomy and imaging artefacts. The paper presents the algorithmic and interactive processing steps implemented in the system, which is based on the open-source Medical Imaging Interaction Toolkit (MITK, www.mitk.org). It is shown how the principles used in MITK enable to assemble the system from modules (functionalities) developed independently from each other. The system allows to produce models of the heart (and other anatomic structures) of individual patients as well as to reproduce unique specimens from pathology collections for teaching purposes.

  18. Advances in three-dimensional rapid prototyping of microfluidic devices for biological applications

    PubMed Central

    O'Neill, P. F.; Ben Azouz, A.; Vázquez, M.; Liu, J.; Marczak, S.; Slouka, Z.; Chang, H. C.; Diamond, D.; Brabazon, D.

    2014-01-01

    The capability of 3D printing technologies for direct production of complex 3D structures in a single step has recently attracted an ever increasing interest within the field of microfluidics. Recently, ultrafast lasers have also allowed developing new methods for production of internal microfluidic channels within the bulk of glass and polymer materials by direct internal 3D laser writing. This review critically summarizes the latest advances in the production of microfluidic 3D structures by using 3D printing technologies and direct internal 3D laser writing fabrication methods. Current applications of these rapid prototyped microfluidic platforms in biology will be also discussed. These include imaging of cells and living organisms, electrochemical detection of viruses and neurotransmitters, and studies in drug transport and induced-release of adenosine triphosphate from erythrocytes. PMID:25538804

  19. Rapid prototyping of three-dimensional microstructures from multiwalled carbon nanotubes

    SciTech Connect

    Hung, W.H.; Kumar, Rajay; Bushmaker, Adam; Cronin, Stephen B.; Bronikowski, Michael J.

    2007-08-27

    The authors report a method for creating three-dimensional carbon nanotube structures, whereby a focused laser beam is used to selectively burn local regions of a dense forest of multiwalled carbon nanotubes. Raman spectroscopy and scanning electron microscopy are used to quantify the threshold for laser burnout and depth of burnout. The minimum power density for burning carbon nanotubes in air is found to be 244 {mu}W/{mu}m{sup 2}. We create various three-dimensional patterns using this method, illustrating its potential use for the rapid prototyping of carbon nanotube microstructures. Undercut profiles, changes in nanotube density, and nanoparticle formation are observed after laser surface treatment and provide insight into the dynamic process of the burnout mechanism.

  20. A web-based rapid prototyping and clinical conversational system that complements electronic patient record system.

    PubMed

    Kim, J H; Ferziger, R; Kawaloff, H B; Sands, D Z; Safran, C; Slack, W V

    2001-01-01

    Even the most extensive hospital information system cannot support all the complex and ever-changing demands associated with a clinical database, such as providing department or personal data forms, and rating scales. Well-designed clinical dialogue programs may facilitate direct interaction of patients with their medical records. Incorporation of extensive and loosely structured clinical data into an existing medical record system is an essential step towards a comprehensive clinical information system, and can best be achieved when the practitioner and the patient directly enter the contents. We have developed a rapid prototyping and clinical conversational system that complements the electronic medical record system, with its generic data structure and standard communication interfaces based on Web technology. We believe our approach can enhance collaboration between consumer-oriented and provider-oriented information systems.

  1. Femtosecond laser rapid prototyping of nanoshells and suspending components towards microfluidic devices.

    PubMed

    Wu, Dong; Chen, Qi-Dai; Niu, Li-Gang; Wang, Jian-Nan; Wang, Juan; Wang, Rui; Xia, Hong; Sun, Hong-Bo

    2009-08-21

    Microfluidic researches are now resorting to advanced micro-nanoprocessing technologies for production of more functional "lab-on-a-chip" systems. However, two-photon polymerization (TPP), a powerful designable micro-nanofabrication approach, has not been put to use on the exciting field, largely due to the difficulties in forming buried channels. Here, we solve the problem by TPP prototyping of nanoshells, for which the usage of the negative tone resin SU-8 is found critical. The fabrication efficiency improved by orders of magnitude, together with the prospect of integration of movable micro-mechanical and optical components into the chip would make TPP a promising enabling tool for the micro-analytical systems. Finally, a 25 microm length functional microvalve in a microfluidic channel was rapidly realized and its "ON" and "OFF" states were tested.

  2. Innovative Applications of Laser Scanning and Rapid Prototype Printing to Rock Breakdown Experiments

    NASA Technical Reports Server (NTRS)

    Bourke, Mary; Viles, Heather; Nicoll, Joe; Lyew-Ayee, Parris; Ghent, Rebecca; Holmlund, James

    2008-01-01

    We present the novel application of two technologies for use in rock breakdown experiments, i.e. close-range, ground-based 3D triangulation scanning and rapid prototype printing. These techniques aid analyses of form-process interactions across the range of scales relevant to breakdown (micron-m). This is achieved through (a) the creation of DEMs (which permit quantitative description and analysis of rock surface morphology and morphological change) and (b) the production of more realistically-shaped experimental blocks. We illustrate the use of these techniques, alongside appropriate data analysis routines, in experiments designed to investigate the persistence of fluvially-derived features in the face of subsequent wind abrasion and weathering. These techniques have a range of potential applications in experimental field and lab-based geomorphic studies beyond those specifically outlined here.

  3. CAD-CAM generated ear cast by means of a laser scanner and rapid prototyping machine.

    PubMed

    Ciocca, Leonardo; Scotti, Roberto

    2004-12-01

    Sculpting a wax ear cast for use when making a definitive prosthesis for a patient who has had auricle ablative surgery, is challenging. It requires a skilled anaplastologist along with complex instrumentation able to perform facial laser scans and reproduce anatomic details. The aim of this article is to present a technique to create a cast by laser scanning a stone cast of the existing ear. A 3D laser scanner develops an integrated 3D digital image of the unaffected ear, which is copied and then mirrored. A rapid prototyping machine collects the necessary data to manufacture the definitive resin ear. This procedure is time and cost effective only if the technology is free of charge.

  4. Innovative Applications of Laser Scanning and Rapid Prototype Printing to Rock Breakdown Experiments

    NASA Technical Reports Server (NTRS)

    Bourke, Mary; Viles, Heather; Nicoll, Joe; Lyew-Ayee, Parris; Ghent, Rebecca; Holmlund, James

    2008-01-01

    We present the novel application of two technologies for use in rock breakdown experiments, i.e. close-range, ground-based 3D triangulation scanning and rapid prototype printing. These techniques aid analyses of form-process interactions across the range of scales relevant to breakdown (micron-m). This is achieved through (a) the creation of DEMs (which permit quantitative description and analysis of rock surface morphology and morphological change) and (b) the production of more realistically-shaped experimental blocks. We illustrate the use of these techniques, alongside appropriate data analysis routines, in experiments designed to investigate the persistence of fluvially-derived features in the face of subsequent wind abrasion and weathering. These techniques have a range of potential applications in experimental field and lab-based geomorphic studies beyond those specifically outlined here.

  5. Product management of making large pieces through Rapid Prototyping PolyJet® technology

    NASA Astrophysics Data System (ADS)

    Belgiu, G.; Cărăuşu, C.; Şerban, D.; Turc, C. G.

    2017-08-01

    The rapid prototyping process has already become a classic manufacturing process for parts and assemblies, either polymeric or metal parts. Besides the well-known advantages and disadvantages of the process, the use of 3D printers has a great inconvenience: the overall dimensions of the parts are limited. Obviously, there is a possibility to purchase a larger (and more expensive) 3D printer, but there are always larger pieces to be manufactured. One solution to this problem is the splitting of parts into several components that can be manufactured. The component parts can then be assembled in a single piece by known methods such as welding, gluing, screwing, etc. This paper shows our experience in making large pieces on the Strarasys® Objet24 printer, pieces larger than the tray sizes. The results obtained are valid for any 3D printer using the PolyJet® process.

  6. Quantitative assessment of biophotonic imaging system performance with phantoms fabricated by rapid prototyping

    NASA Astrophysics Data System (ADS)

    Wang, Jianting; Coburn, James; Woolsey, Nicholas; Liang, Chia-Pin; Ramella-Roman, Jessica; Chen, Yu; Pfefer, Joshua

    2014-03-01

    In biophotonic imaging, turbid phantoms that are low-cost, biologically-relevant, and durable are desired for standardized performance assessment. Such phantoms often contain inclusions of varying depths and sizes in order to quantify key image quality characteristics such as penetration depth, sensitivity and contrast detectability. The emerging technique of rapid prototyping with three-dimensional (3D) printers provides a potentially revolutionary way to fabricate these structures. Towards this goal, we have characterized the optical properties and morphology of phantoms fabricated by two 3D printing approaches: thermosoftening and photopolymerization. Material optical properties were measured by spectrophotometry while the morphology of phantoms incorporating 0.2-1.0 mm diameter channels was studied by μCT, optical coherence tomography (OCT) and optical microscopy. A near-infrared absorbing dye and nanorods at several concentrations were injected into channels to evaluate detectability with a near-infrared hyperspectral reflectance imaging (HRI) system (650-1100 nm). Phantoms exhibited biologically-relevant scattering and low absorption across visible and near-infrared wavelengths. Although limitations in resolution were noted, channels with diameters of 0.4 mm or more could be reliably fabricated. The most significant problem noted was the porosity of phantoms generated with the thermosoftening-based printer. The aforementioned three imaging methods provided a valuable mix of insights into phantom morphology and may also be useful for detailed structural inspection of medical devices fabricated by rapid prototyping, such as customized implants. Overall, our findings indicate that 3D printing has significant potential as a method for fabricating well-characterized, standard phantoms for medical imaging modalities such as HRI.

  7. Novel CAD/CAM rapid prototyping of next-generation biomedical devices

    NASA Astrophysics Data System (ADS)

    Doraiswamy, Anand

    An aging population with growing healthcare needs demands multifaceted tools for diagnosis and treatment of health conditions. In the near-future, drug-administration devices, implantable devices/sensors, enhanced prosthesis, artificial and unique functional tissue constructs will become increasingly significant. Conventional technologies for mass-produced implants do not adequately take individual patient anatomy into consideration. Development of novel CAD/CAM rapid prototyping techniques may significantly accelerate progress of these devices for next-generation patient-care. In this dissertation, several novel rapid prototyping techniques have been introduced for next-generation biomedical applications. Two-photon polymerization was developed to microfabricate scaffolds for tissue engineering, microneedles for drug-delivery and ossicular replacement prostheses. Various photoplymers were evaluated for feasibility, mechanical properties, cytotoxicity, and surface properties. Laser direct write using MDW was utilized for developing microstructures of bioceramics such as hydroxyapatite, and viable mammalian osteosarcoma cells. CAD/CAM laser micromachining (CLM) was developed to engineer biointerfaces as surface recognition regions for differential adherence of cells and growth into tissue-like networks. CLM was also developed for engineering multi-cellular vascular networks. Cytotoxic evaluations and growth studies demonstrated VEGF-induced proliferation of HAAE-1 human aortic endothelial cells with inhibition of HA-VSMC human aortic smooth muscle cells. Finally, piiezoelectric inkjet printing was developed for controlled administration of natural and synthetic adhesives to overcome several problems associated with conventional tissue bonding materials, and greatly improve wound-repair in next generation eye repair, fracture fixation, organ fixation, wound closure, tissue engineering, and drug delivery devices.

  8. Trial fitting of a removable partial denture framework made using computer-aided design and rapid prototyping techniques.

    PubMed

    Bibb, R J; Eggbeer, D; Williams, R J; Woodward, A

    2006-10-01

    Previous studies of CAD/CAM-produced sacrificial patterns for removable partial denture frameworks have been documented but to date, no such restorations have been test-fitted to a patient. This paper provides details of the first trial fitting to a patient of an RPD framework, the sacrificial pattern of which was produced by CAD/CAM and RP technologies. A cast of the patient was scanned and the normal procedures of dental surveying and pattern build were undertaken with reference to the scanned model using computer-aided design. A sacrificial pattern of the design was produced by rapid prototyping technology. After spruing the pattern, investment-casting and finishing techniques were carried out according to conventional principles. The framework was successfully trial-fitted to the patient and clinically judged to be acceptable for the next stage of denture fabrication, that of adding acrylic bases and artificial teeth.

  9. CAD/CAM and rapid prototyped scaffold construction for bone regenerative medicine and surgical transfer of virtual planning: a pilot study.

    PubMed

    Ciocca, L; De Crescenzio, F; Fantini, M; Scotti, R

    2009-01-01

    We developed a model to test new bone constructs to replace spare skeletal segments originating from new generation scaffolds for bone marrow-derived mesenchymal stem cells. Using computed tomography (CT) data, scaffolds were defined using computer-aided design/computer-aided manufacturing (CAD/CAM) for rapid prototyping by three-dimensional (3D) printing. A bone defect was created in pig mandible ramus by condyle resection for CT and CAD/CAM elaboration of bone volume for cutting and scaffold restoration. The protocol produced a perfect-fitting bone substitute model for rapid prototyped hydroxyapatite (HA) scaffolds. A surgical guide system was developed to accurately reproduce virtually planned bone sectioning procedures in animal models to obtain a perfect fit during surgery.

  10. Integration of the NASA Land Information System as an Application Framework into the MRC Rapid Prototyping Capabilities Infrastructure

    NASA Astrophysics Data System (ADS)

    Anantharaj, V.; Peters-Lidard, C.; Houser, P.; Mostovoy, G.; Haupt, T.; Moorhead, R.; Kumar, S.

    2006-12-01

    The Mississippi Research Consortium (MRC) is implementing a computational Rapid Prototyping Capabilities (RPC) infrastructure, based on a systems engineering concept, advocated by the NASA Applied Sciences Program, in order to identify, evaluate, and integrate research results for applications. The NASA Land Information System (LIS) is a "functional Land Data Assimilation System (LDAS)" that incorporates a suite of land models in an interoperable computational framework. LIS currently is comprised of a LIS core, a number of community land models, data servers, and visualization systems - integrated in a high-performance computing environment. LIS uses model independent software frameworks, such as the Earth Systems Modeling Framework (ESMF) and Assistance for Land Modeling Activities (ALMA), in order to enable interactions with other earth system model and decision support systems (DSS). The LIS user interface (UI) can be used to query, browse, and download LIS derived products. Besides, any clients that support OpenDAP can be used to access the model results. NASA LIS has been identified to be integrated into the RPC infrastructure as a cross-cutting applications framework (AF). The land models in LIS incorporate surface and atmospheric parameters of temperature, snow/water, vegetation, albedo, soil conditions, topography, and radiation. Many of these parameters are available from in- situ observations, numerical model analysis, and from NASA, NOAA, and other remote sensing satellite platforms at various spatial and temporal resolutions. Since the land models in LIS require normal spin-up times of 5 years or more for most experiments, the necessary multi-year retrospective initialization and forcing fields (estimated to grow to 10 TB in size) are also stored and managed in the RPC infrastructure. The computational resources, available to LIS via the RPC infrastructure, support e-Science experiments involving the global modeling of land-atmosphere studies at 1km

  11. Rapid sealing of porcine renal blood vessels, ex vivo, using a high power, 1470-nm laser, and laparoscopic prototype.

    PubMed

    Hardy, Luke A; Hutchens, Thomas C; Larson, Eric R; Gonzalez, David A; Chang, Chun-Hung; Nau, William H; Fried, Nathaniel M

    2017-05-01

    Energy-based, radiofrequency (RF) and ultrasonic (US) devices currently provide rapid sealing of blood vessels during laparoscopic procedures. We are exploring infrared lasers as an alternate energy modality for vessel sealing, capable of generating less collateral thermal damage. Previous studies demonstrated feasibility of sealing vessels in an in vivo porcine model using a 1470-nm laser. However, the initial prototype was designed for testing in open surgery and featured tissue clasping and light delivery mechanisms incompatible with laparoscopic surgery. In this study, a laparoscopic prototype similar to devices currently in surgical use was developed, and performance tests were conducted on porcine renal blood vessels, ex vivo. The 5-mm outer-diameter laparoscopic prototype featured a traditional Maryland jaw configuration that enables tissue manipulation and blunt dissection. Laser energy was delivered through a 550 - ? m -core-diameter optical fiber with side-delivery from the lower jaw and beam dimensions of 18 - mm ? length × 1.2 - mm ? width . The 1470-nm diode laser delivered 68 W with 3-s activation time, consistent with vessel seal times associated with RF and US-based devices. A total of 69 fresh porcine renal vessels with mean diameter of 3.3 ± 1.7 ?? mm were tested, ex vivo. Vessels smaller than 5-mm diameter were consistently sealed (48/51) with burst pressures greater than malignant hypertension blood pressure (180 mmHg), averaging 1038 ± 474 ?? mmHg . Vessels larger than 5 mm were not consistently sealed (6/18), yielding burst pressures of only 174 ± 221 ?? mmHg . Seal width, thermal damage zone, and thermal spread averaged 1.7 ± 0.8 , 3.4 ± 0.7 , and 1.0 ±

  12. Rapid prototyping of carbon-based chemiresistive gas sensors on paper

    PubMed Central

    Mirica, Katherine A.; Azzarelli, Joseph M.; Weis, Jonathan G.; Schnorr, Jan M.; Swager, Timothy M.

    2013-01-01

    Chemically functionalized carbon nanotubes (CNTs) are promising materials for sensing of gases and volatile organic compounds. However, the poor solubility of carbon nanotubes hinders their chemical functionalization and the subsequent integration of these materials into devices. This manuscript describes a solvent-free procedure for rapid prototyping of selective chemiresistors from CNTs and graphite on the surface of paper. This procedure enables fabrication of functional gas sensors from commercially available starting materials in less than 15 min. The first step of this procedure involves the generation of solid composites of CNTs or graphite with small molecule selectors—designed to interact with specific classes of gaseous analytes—by solvent-free mechanical mixing in a ball mill and subsequent compression. The second step involves deposition of chemiresistive sensors by mechanical abrasion of these solid composites onto the surface of paper. Parallel fabrication of multiple chemiresistors from diverse composites rapidly generates cross-reactive arrays capable of sensing and differentiating gases and volatile organic compounds at part-per-million and part-per-thousand concentrations. PMID:23942132

  13. Rapid prototyping of nanotube-based devices using topology-optimized microgrippers.

    PubMed

    Sardan, O; Eichhorn, V; Petersen, D H; Fatikow, S; Sigmund, O; Bøggild, P

    2008-12-10

    Nanorobotic handling of carbon nanotubes (CNTs) using microgrippers is one of the most promising approaches for the rapid characterization of the CNTs and also for the assembly of prototypic nanotube-based devices. In this paper, we present pick-and-place nanomanipulation of multi-walled CNTs in a rapid and a reproducible manner. We placed CNTs on copper TEM grids for structural analysis and on AFM probes for the assembly of AFM super-tips. We used electrothermally actuated polysilicon microgrippers designed using topology optimization in the experiments. The microgrippers are able to open as well as close. Topology optimization leads to a 10-100 times improvement of the gripping force compared to conventional designs of similar size. Furthermore, we improved our nanorobotic system to offer more degrees of freedom. TEM investigation of the CNTs shows that the multi-walled tubes are coated with an amorphous carbon layer, which is locally removed at the contact points with the microgripper. The assembled AFM super-tips are used for AFM measurements of microstructures with high aspect ratios.

  14. Rapid prototyping of carbon-based chemiresistive gas sensors on paper.

    PubMed

    Mirica, Katherine A; Azzarelli, Joseph M; Weis, Jonathan G; Schnorr, Jan M; Swager, Timothy M

    2013-08-27

    Chemically functionalized carbon nanotubes (CNTs) are promising materials for sensing of gases and volatile organic compounds. However, the poor solubility of carbon nanotubes hinders their chemical functionalization and the subsequent integration of these materials into devices. This manuscript describes a solvent-free procedure for rapid prototyping of selective chemiresistors from CNTs and graphite on the surface of paper. This procedure enables fabrication of functional gas sensors from commercially available starting materials in less than 15 min. The first step of this procedure involves the generation of solid composites of CNTs or graphite with small molecule selectors--designed to interact with specific classes of gaseous analytes--by solvent-free mechanical mixing in a ball mill and subsequent compression. The second step involves deposition of chemiresistive sensors by mechanical abrasion of these solid composites onto the surface of paper. Parallel fabrication of multiple chemiresistors from diverse composites rapidly generates cross-reactive arrays capable of sensing and differentiating gases and volatile organic compounds at part-per-million and part-per-thousand concentrations.

  15. Assessment of Data Assimilation with the Prototype High Resolution Rapid Refresh for Alaska (HRRRAK)

    NASA Technical Reports Server (NTRS)

    Harrison, Kayla; Morton, Don; Zavodsky, Brad; Chou, Shih; Hu, Ming

    2012-01-01

    The Arctic Region Supercomputing Center has been running a quasi-operational prototype of a High Resolution Rapid Refresh for Alaska (HRRRAK) at 3km resolution, initialized by the 13km Rapid Refresh (RR). Although the RR assimilates a broad range of observations into its analyses, experiments with the HRRRAK suggest that there may be added value in assimilating observations into the 3km initial conditions, downscaled from the 13km RR analyses. The NASA Short-term Prediction Research and Transition (SPoRT) group has been using assimilated data from the Atmospheric Infrared Sounder (AIRS) in WRF and WRF-Var simulations since 2004 with promising results. The sounder is aboard NASA s Aqua satellite, and provides vertical profiles of temperature and humidity. The Gridpoint Statistical Interpolation (GSI) system is then used to assimilate these vertical profiles into WRF forecasts. In this work, we assess the use of AIRS data in combination with other global data assimilation products on non-assimilated HRRRAK case studies. Two separate weather events will be assessed to qualitatively and quantitatively assess the impacts of AIRS data on HRRRAK forecasts.

  16. A microcontroller platform for the rapid prototyping of functional electrical stimulation-based gait neuroprostheses.

    PubMed

    Luzio de Melo, Paulo; da Silva, Miguel Tavares; Martins, Jorge; Newman, Dava

    2015-05-01

    Functional electrical stimulation (FES) has been used over the last decades as a method to rehabilitate lost motor functions of individuals with spinal cord injury, multiple sclerosis, and post-stroke hemiparesis. Within this field, researchers in need of developing FES-based control solutions for specific disabilities often have to choose between either the acquisition and integration of high-performance industry-level systems, which are rather expensive and hardly portable, or develop custom-made portable solutions, which despite their lower cost, usually require expert-level electronic skills. Here, a flexible low-cost microcontroller-based platform for rapid prototyping of FES neuroprostheses is presented, designed for reduced execution complexity, development time, and production cost. For this reason, the Arduino open-source microcontroller platform was used, together with off-the-shelf components whenever possible. The developed system enables the rapid deployment of portable FES-based gait neuroprostheses, being flexible enough to allow simple open-loop strategies but also more complex closed-loop solutions. The system is based on a modular architecture that allows the development of optimized solutions depending on the desired FES applications, even though the design and testing of the platform were focused toward drop foot correction. The flexibility of the system was demonstrated using two algorithms targeting drop foot condition within different experimental setups. Successful bench testing of the device in healthy subjects demonstrated these neuroprosthesis platform capabilities to correct drop foot.

  17. Pulseq: A rapid and hardware-independent pulse sequence prototyping framework.

    PubMed

    Layton, Kelvin J; Kroboth, Stefan; Jia, Feng; Littin, Sebastian; Yu, Huijun; Leupold, Jochen; Nielsen, Jon-Fredrik; Stöcker, Tony; Zaitsev, Maxim

    2017-04-01

    Implementing new magnetic resonance experiments, or sequences, often involves extensive programming on vendor-specific platforms, which can be time consuming and costly. This situation is exacerbated when research sequences need to be implemented on several platforms simultaneously, for example, at different field strengths. This work presents an alternative programming environment that is hardware-independent, open-source, and promotes rapid sequence prototyping. A novel file format is described to efficiently store the hardware events and timing information required for an MR pulse sequence. Platform-dependent interpreter modules convert the file to appropriate instructions to run the sequence on MR hardware. Sequences can be designed in high-level languages, such as MATLAB, or with a graphical interface. Spin physics simulation tools are incorporated into the framework, allowing for comparison between real and virtual experiments. Minimal effort is required to implement relatively advanced sequences using the tools provided. Sequences are executed on three different MR platforms, demonstrating the flexibility of the approach. A high-level, flexible and hardware-independent approach to sequence programming is ideal for the rapid development of new sequences. The framework is currently not suitable for large patient studies or routine scanning although this would be possible with deeper integration into existing workflows. Magn Reson Med 77:1544-1552, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  18. Complete arch implant rehabilitation using subtractive rapid prototyping and porcelain fused to zirconia prosthesis: a clinical report.

    PubMed

    Papaspyridakos, Panos; Lal, Kunal

    2008-09-01

    The applications of various technological advances in implant dentistry and in all aspects of the diagnostic, treatment planning, surgical, and restorative phases are gaining popularity. Additive rapid prototyping and computer-aided design/computer-aided manufacturing (CAD/CAM) technology are used to generate stereolithographic surgical guides and prefabricated interim prostheses to facilitate implant surgery and immediate loading, respectively. Subtractive rapid prototyping is used for fabrication of zirconia frameworks for definitive implant prostheses. This clinical report describes the comprehensive application of these technological advances in implant rehabilitation to optimize surgical and prosthodontic outcomes as well as patient comfort.

  19. A frame-based domain-specific language for rapid prototyping of FPGA-based software-defined radios

    NASA Astrophysics Data System (ADS)

    Ouedraogo, Ganda Stephane; Gautier, Matthieu; Sentieys, Olivier

    2014-12-01

    The field-programmable gate array (FPGA) technology is expected to play a key role in the development of software-defined radio (SDR) platforms. As this technology evolves, low-level designing methods for prototyping FPGA-based applications did not change throughout the decades. In the outstanding context of SDR, it is important to rapidly implement new waveforms to fulfill such a stringent flexibility paradigm. At the current time, different proposals have defined, through software-based approaches, some efficient methods to prototype SDR waveforms in a processor-based running environment. This paper describes a novel design flow for FPGA-based SDR applications. This flow relies upon high-level synthesis (HLS) principles and leverages the nascent HLS tools. Its entry point is a domain-specific language (DSL) which handles the complexity of programming an FPGA and integrates some SDR features so as to enable automatic waveform control generation from a data frame model. Two waveforms (IEEE 802.15.4 and IEEE 802.11a) have been designed and explored via this new methodology, and the results are highlighted in this paper.

  20. Air injection test on a Kaplan turbine: prototype - model comparison

    NASA Astrophysics Data System (ADS)

    Angulo, M.; Rivetti, A.; Díaz, L.; Liscia, S.

    2016-11-01

    Air injection is a very well-known resource to reduce pressure pulsation magnitude in turbines, especially on Francis type. In the case of large Kaplan designs, even when not so usual, it could be a solution to mitigate vibrations arising when tip vortex cavitation phenomenon becomes erosive and induces structural vibrations. In order to study this alternative, aeration tests were performed on a Kaplan turbine at model and prototype scales. The research was focused on efficiency of different air flow rates injected in reducing vibrations, especially at the draft tube and the discharge ring and also in the efficiency drop magnitude. It was found that results on both scales presents the same trend in particular for vibration levels at the discharge ring. The efficiency drop was overestimated on model tests while on prototype were less than 0.2 % for all power output. On prototype, air has a beneficial effect in reducing pressure fluctuations up to 0.2 ‰ of air flow rate. On model high speed image computing helped to quantify the volume of tip vortex cavitation that is strongly correlated with the vibration level. The hydrophone measurements did not capture the cavitation intensity when air is injected, however on prototype, it was detected by a sonometer installed at the draft tube access gallery.

  1. Rapid prototyping of interfacing microcomponents for printed circuit board-level optical interconnects

    NASA Astrophysics Data System (ADS)

    Van Erps, Jürgen; Vervaeke, Michael; Thienpont, Hugo

    2012-01-01

    One of the important challenges for the deployment of the emerging breed of nanotechnology components is interfacing them with the external world, preferably accomplished with low-cost micro-optical devices. For the fabrication of this kind of micro-optical components, we make use of deep proton writing (DPW) as a generic rapid prototyping technology. DPW consists of bombarding polymer samples with swift protons, which results after chemical processing steps in high quality micro-optical components. The strength of the DPW micro-machining technology is the ability to fabricate monolithic building blocks that include micro-optical and mechanical functionalities which can be precisely integrated into more complex photonic systems. In this paper we give an overview of the process steps of the technology and we present several examples of micro-optical and micro-mechanical components, fabricated through DPW, targeting applications in printed circuit baordlevel optical interconnections. These include: high-precision 2-D fiber connectors, discrete out-of-plane coupling structures featuring high-quality 45° and curved micro-mirrors, arrays of high aspect ratio micro-pillars and backplane connectors. While DPW is clearly not a mass fabrication technique as such, one of its assets is that once the master component has been prototyped, a metal mould can be generated from the DPW master by applying electroplating. After removal of the plastic master, this metal mould can be used as a shim in a final microinjection moulding or hot embossing step. This way, the master component can be mass-produced at low cost in a wide variety of high-tech plastics.

  2. Deep proton writing: a powerful rapid prototyping technology for various micro-optical components

    NASA Astrophysics Data System (ADS)

    Van Erps, Jürgen; Vervaeke, Michael; Debaes, Christof; Ottevaere, Heidi; Van Overmeire, Sara; Hermanne, Alex; Thienpont, Hugo

    2010-05-01

    One of the important challenges for the deployment of the emerging breed of nanotechnology components is interfacing them with the external world, preferably accomplished with low-cost micro-optical devices. For the fabrication of this kind of micro-optical modules, we make use of deep proton writing (DPW) as a generic rapid prototyping technology. DPW consists of bombarding polymer samples with swift protons, which results after chemical processing steps in high quality micro-optical components. The strength of the DPW micro-machining technology is the ability to fabricate monolithic building blocks that include micro-optical and mechanical functionalities which can be precisely integrated into more complex photonic systems. In this paper we give an overview of the process steps of the technology and we present several examples of micro-optical and micro-mechanical components, fabricated through DPW, targeting applications in optical interconnections and in bio-photonics. These include: high-precision 2-D fiber connectors, out-of-plane coupling structures featuring high-quality 45° and curved micro-mirrors, arrays of high aspect ratio micro-pillars, and fluorescence and absorption detection bio-photonics modules. While DPW is clearly not a mass fabrication technique as such, one of its assets is that once the master component has been prototyped, a metal mould can be generated from the DPW master by applying electroplating. After removal of the plastic master, this metal mould can be used as a shim in a final microinjection moulding or hot embossing step. This way, the master component can be mass-produced at low cost in a wide variety of high-tech plastics.

  3. Rapid Prototyping of Hyperspectral Image Analysis Algorithms for Improved Invasive Species Decision Support Tools

    NASA Astrophysics Data System (ADS)

    Bruce, L. M.; Ball, J. E.; Evangilista, P.; Stohlgren, T. J.

    2006-12-01

    Nonnative invasive species adversely impact ecosystems, causing loss of native plant diversity, species extinction, and impairment of wildlife habitats. As a result, over the past decade federal and state agencies and nongovernmental organizations have begun to work more closely together to address the management of invasive species. In 2005, approximately 500M dollars was budgeted by U.S. Federal Agencies for the management of invasive species. Despite extensive expenditures, most of the methods used to detect and quantify the distribution of these invaders are ad hoc, at best. Likewise, decisions on the type of management techniques to be used or evaluation of the success of these methods are typically non-systematic. More efficient methods to detect or predict the occurrence of these species, as well as the incorporation of this knowledge into decision support systems, are greatly needed. In this project, rapid prototyping capabilities (RPC) are utilized for an invasive species application. More precisely, our recently developed analysis techniques for hyperspectral imagery are being prototyped for inclusion in the national Invasive Species Forecasting System (ISFS). The current ecological forecasting tools in ISFS will be compared to our hyperspectral-based invasives prediction algorithms to determine if/how the newer algorithms enhance the performance of ISFS. The PIs have researched the use of remotely sensed multispectral and hyperspectral reflectance data for the detection of invasive vegetative species. As a result, the PI has designed, implemented, and benchmarked various target detection systems that utilize remotely sensed data. These systems have been designed to make decisions based on a variety of remotely sensed data, including high spectral/spatial resolution hyperspectral signatures (1000's of spectral bands, such as those measured using ASD handheld devices), moderate spectral/spatial resolution hyperspectral images (100's of spectral bands, such

  4. Semi-automated delineation of breast cancer tumors and subsequent materialization using three-dimensional printing (rapid prototyping).

    PubMed

    Schulz-Wendtland, Rüdiger; Harz, Markus; Meier-Meitinger, Martina; Brehm, Barbara; Wacker, Till; Hahn, Horst K; Wagner, Florian; Wittenberg, Thomas; Beckmann, Matthias W; Uder, Michael; Fasching, Peter A; Emons, Julius

    2017-03-01

    Three-dimensional (3D) printing has become widely available, and a few cases of its use in clinical practice have been described. The aim of this study was to explore facilities for the semi-automated delineation of breast cancer tumors and to assess the feasibility of 3D printing of breast cancer tumors. In a case series of five patients, different 3D imaging methods-magnetic resonance imaging (MRI), digital breast tomosynthesis (DBT), and 3D ultrasound-were used to capture 3D data for breast cancer tumors. The volumes of the breast tumors were calculated to assess the comparability of the breast tumor models, and the MRI information was used to render models on a commercially available 3D printer to materialize the tumors. The tumor volumes calculated from the different 3D methods appeared to be comparable. Tumor models with volumes between 325 mm(3) and 7,770 mm(3) were printed and compared with the models rendered from MRI. The materialization of the tumors reflected the computer models of them. 3D printing (rapid prototyping) appears to be feasible. Scenarios for the clinical use of the technology might include presenting the model to the surgeon to provide a better understanding of the tumor's spatial characteristics in the breast, in order to improve decision-making in relation to neoadjuvant chemotherapy or surgical approaches. J. Surg. Oncol. 2017;115:238-242. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  5. Rapid sealing of porcine renal blood vessels, ex vivo, using a high power, 1470-nm laser, and laparoscopic prototype

    NASA Astrophysics Data System (ADS)

    Hardy, Luke A.; Hutchens, Thomas C.; Larson, Eric R.; Gonzalez, David A.; Chang, Chun-Hung; Nau, William H.; Fried, Nathaniel M.

    2017-05-01

    Energy-based, radiofrequency (RF) and ultrasonic (US) devices currently provide rapid sealing of blood vessels during laparoscopic procedures. We are exploring infrared lasers as an alternate energy modality for vessel sealing, capable of generating less collateral thermal damage. Previous studies demonstrated feasibility of sealing vessels in an in vivo porcine model using a 1470-nm laser. However, the initial prototype was designed for testing in open surgery and featured tissue clasping and light delivery mechanisms incompatible with laparoscopic surgery. In this study, a laparoscopic prototype similar to devices currently in surgical use was developed, and performance tests were conducted on porcine renal blood vessels, ex vivo. The 5-mm outer-diameter laparoscopic prototype featured a traditional Maryland jaw configuration that enables tissue manipulation and blunt dissection. Laser energy was delivered through a 550-μm-core-diameter optical fiber with side-delivery from the lower jaw and beam dimensions of 18-mm length×1.2-mm width. The 1470-nm diode laser delivered 68 W with 3-s activation time, consistent with vessel seal times associated with RF and US-based devices. A total of 69 fresh porcine renal vessels with mean diameter of 3.3±1.7 mm were tested, ex vivo. Vessels smaller than 5-mm diameter were consistently sealed (48/51) with burst pressures greater than malignant hypertension blood pressure (180 mmHg), averaging 1038±474 mmHg. Vessels larger than 5 mm were not consistently sealed (6/18), yielding burst pressures of only 174±221 mmHg. Seal width, thermal damage zone, and thermal spread averaged 1.7±0.8, 3.4±0.7, and 1.0±0.4 mm, respectively. Results demonstrated that the 5-mm optical laparoscopic prototype consistently sealed vessels less than 5-mm diameter with low thermal spread. Further in vivo studies are planned to test the performance across a variety of vessels and tissues.

  6. Planar array stack design aided by rapid prototyping in development of air-breathing PEMFC

    NASA Astrophysics Data System (ADS)

    Chen, Chen-Yu; Lai, Wei-Hsiang; Weng, Biing-Jyh; Chuang, Huey-Jan; Hsieh, Ching-Yuan; Kung, Chien-Chih

    The polymer electrolyte membrane fuel cell (PEMFC) is one of the most important research topics in the new and clean energy area. The middle or high power PEMFCs can be applied to the transportation or the distributed power system. But for the small power application, it is needed to match the power requirement of the product generally. On the other hand, the direct methanol fuel cell (DMFC) is one of the most common type that researchers are interested in, but recently the miniature or the micro-PEMFCs attract more attention due to their advantages of high open circuit voltage and high power density. The objective of this study is to develop a new air-breathing planar array fuel cell stacked from 10 cells made by rapid prototyping technology which has potential for fast commercial design, low cost manufacturing, and even without converters/inverters for the system. In this paper, the main material of flow field plates is acrylonitrile-butadiene-styrene (ABS) which allows the fuel cell be mass-manufactured by plastic injection molding technology. The rapid prototyping technology is applied to construct the prototype and verify the practicability of the proposed stack design. A 10-cell air-breathing miniature PEMFC stack with a volume of 6 cm × 6 cm × 0.9 cm is developed and tested. Its segmented membrane electrode assembly (MEA) is designed with the active surface area of 1.3 cm × 1.3 cm in each individual MEA. The platinum loading at anode and cathode are 0.2 mg cm -2 and 0.4 mg cm -2, respectively. Results show that the peak power densities of the parallel connected and serial connected stack are 99 mW cm -2 at 0.425 V and 92 mW cm -2 at 4.25 V, respectively under the conditions of 70 °C relative saturated humidity (i.e., dew point temperature), ambient temperature and free convection air. Besides, the stack performance is increased under forced convection. If the cell surface air is blown by an electric fan, the peak power densities of parallel connected and

  7. Virtual reality surgical planning for maxillofacial distraction osteogenesis: the role of reverse engineering rapid prototyping and cooperative work.

    PubMed

    Robiony, Massimo; Salvo, Iolanda; Costa, Fabio; Zerman, Nicoletta; Bazzocchi, Massimo; Toso, Francesco; Bandera, Camillo; Filippi, Stefano; Felice, Martina; Politi, Massimo

    2007-06-01

    The purpose of this article is the demonstration of virtual reality (VR) and rapid prototyping (RP) in surgical planning in maxillofacial surgery. The authors emphasize the role of reverse engineering (RE) and RP, suggesting a model of cooperative work, with the interaction of maxillofacial surgeons, radiologists, and engineers. Data acquisition is performed using computed tomography. The 3D model is the result of RE practices based on image segmentation, and the real model is produced via stereolithography. Virtual simulations are performed on the 3D model obtained from image segmentation. All these stages require the interaction and collaboration of various experts: maxillofacial surgeons, radiologists, and RE and RP experts. VR and stereolithography models represent a new technology to help the surgeon who has to work in cooperation with engineers and radiologists to improve the results in surgical planning of maxillofacial distraction. When performing the VR simulation, surgeons and engineers operate together in order to optimize the exploitation of the instruments available. Both VR and RP, with different and complementary advantages and limitations, can improve surgical planning activities and this is particularly effective when dealing with complex anatomical structures in maxillofacial surgery.

  8. Rapid prototyping of update algorithm of discrete Fourier transform for real-time signal processing

    NASA Astrophysics Data System (ADS)

    Kakad, Yogendra P.; Sherlock, Barry G.; Chatapuram, Krishnan V.; Bishop, Stephen

    2001-10-01

    An algorithm is developed in the companion paper, to update the existing DFT to represent the new data series that results when a new signal point is received. Updating the DFT in this way uses less computation than directly evaluating the DFT using the FFT algorithm, This reduces the computational order by a factor of log2 N. The algorithm is able to work in the presence of data window function, for use with rectangular window, the split triangular, Hanning, Hamming, and Blackman windows. In this paper, a hardware implementation of this algorithm, using FPGA technology, is outlined. Unlike traditional fully customized VLSI circuits, FPGAs represent a technical break through in the corresponding industry. The FPGA implements thousands of gates of logic in a single IC chip and it can be programmed by users at their site in a few seconds or less depending on the type of device used. The risk is low and the development time is short. The advantages have made FPGAs very popular for rapid prototyping of algorithms in the area of digital communication, digital signal processing, and image processing. Our paper addresses the related issues of implementation using hardware descriptive language in the development of the design and the subsequent downloading on the programmable hardware chip.

  9. Rapid prototyping of reflectors for vehicle lighting using laser activated remote phosphor

    NASA Astrophysics Data System (ADS)

    Lachmayer, Roland; Kloppenburg, Gerolf; Wolf, Alexander

    2015-03-01

    Bright white light sources are of significant importance for automotive front lighting systems. Today's upper class vehicles mainly use HID or LED as light source. As a further step in this development laser diode based systems offer high luminance, efficiency and allow the realization of new styling concepts and new dynamic lighting functions. These white laser diode systems can either be realized by mixing different spectral sources or by combining diodes with specific phosphors. Based on the approach of generating light using a laser and remote phosphor, lighting modules are manufactured. Four blue laser diodes (450 nm) are used to activate a phosphor coating and thus to achieve white light. A segmented paraboloid reflector generates the desired light distribution for an additional car headlamp. We use high speed milling and selective laser melting to build the reflector system for this lighting module. We compare the spectral reflection grade of these materials. Furthermore the generated modules are analyzed regarding their efficiency and light distribution. The use of Rapid Prototyping technologies allows an early validation of the chosen concept and is supposed to reduce cost and time in the product development process significantly. Therefor we discuss costs and times of the applied manufacturing technologies.

  10. Photodefinable polydimethylsiloxane (PDMS) for rapid lab-on-a-chip prototyping.

    PubMed

    Bhagat, Ali Asgar S; Jothimuthu, Preetha; Papautsky, Ian

    2007-09-01

    In this paper, we introduce a new and simple method of patterning polydimethylsiloxane (PDMS) directly using benzophenone as a photoinitiator. The photodefinable PDMS mixture (photoPDMS) is positive-acting and only sensitive to light below 365 nm, permitting processing under normal ambient light. Features of the order of 100 microm, which are sufficiently small for most microfluidic applications, were successfully fabricated using this novel process. A parametric study of process parameters was performed to optimize the fabrication. As a demonstration, microfluidic channels of varying dimensions were successfully fabricated using this process and experimentally characterized using fluorescence microscopy. To further demonstrate photoPDMS potential, thin (<30 microm) free-standing films with through patterns were fabricated and successfully used as shadow masks. The photoPDMS process completely eliminates the need for a master, permits processing under normal ambient light conditions, and makes fabrication fast and simple. This process for rapid prototyping of low-cost, disposable LOCs can be accomplished without cleanroom facilities and thus can be employed for a wide range of applications.

  11. Rapid prototyping of multi-scale biomedical microdevices by combining additive manufacturing technologies.

    PubMed

    Hengsbach, Stefan; Lantada, Andrés Díaz

    2014-08-01

    The possibility of designing and manufacturing biomedical microdevices with multiple length-scale geometries can help to promote special interactions both with their environment and with surrounding biological systems. These interactions aim to enhance biocompatibility and overall performance by using biomimetic approaches. In this paper, we present a design and manufacturing procedure for obtaining multi-scale biomedical microsystems based on the combination of two additive manufacturing processes: a conventional laser writer to manufacture the overall device structure, and a direct-laser writer based on two-photon polymerization to yield finer details. The process excels for its versatility, accuracy and manufacturing speed and allows for the manufacture of microsystems and implants with overall sizes up to several millimeters and with details down to sub-micrometric structures. As an application example we have focused on manufacturing a biomedical microsystem to analyze the impact of microtextured surfaces on cell motility. This process yielded a relevant increase in precision and manufacturing speed when compared with more conventional rapid prototyping procedures.

  12. Accuracy Assessment of Using Rapid Prototyping Drill Templates for Atlantoaxial Screw Placement: A Cadaver Study

    PubMed Central

    Guo, Shuai; Lu, Teng; Hu, Qiaolong; Yang, Baohui; He, Xijing

    2016-01-01

    Purpose. To preliminarily evaluate the feasibility and accuracy of using rapid prototyping drill templates (RPDTs) for C1 lateral mass screw (C1-LMS) and C2 pedicle screw (C2-PS) placement. Methods. 23 formalin-fixed craniocervical cadaver specimens were randomly divided into two groups. In the conventional method group, intraoperative fluoroscopy was used to assist the screw placement. In the RPDT navigation group, specific RPDTs were constructed for each specimen and were used intraoperatively for screw placement navigation. The screw position, the operating time, and the fluoroscopy time for each screw placement were compared between the 2 groups. Results. Compared with the conventional method, the RPDT technique significantly increased the placement accuracy of the C2-PS (p < 0.05). In the axial plane, using RPDTs also significantly increased C1-LMS placement accuracy (p < 0.05). In the sagittal plane, although using RPDTs had a very high accuracy rate (100%) in C1-LMS placement, it was not statistically significant compared with the conventional method (p > 0.05). Moreover, the RPDT technique significantly decreased the operating and fluoroscopy times. Conclusion. Using RPDTs significantly increases the accuracy of C1-LMS and C2-PS placement while decreasing the screw placement time and the radiation exposure. Due to these advantages, this approach is worth promoting for use in the Harms technique. PMID:28004004

  13. Rapid Prototyping of a High Sensitivity Graphene Based Glucose Sensor Strip

    PubMed Central

    Tehrani, Farshad; Reiner, Lisa; Bavarian, Behzad

    2015-01-01

    A rapid prototyping of an inexpensive, disposable graphene and copper nanocomposite sensor strip using polymeric flexible substrate for highly sensitive and selective nonenzymatic glucose detection has been developed and tested for direct oxidization of glucose. The CuNPs were electrochemically deposited on to the graphene sheets to improve electron transfer rates and to enhance electrocatalytic activity toward glucose. The graphene based electrode with CuNPs demonstrated a high degree of sensitivity (1101.3±56 μA/mM.cm2), excellent selectivity (without an interference with Ascorbic Acid, Uric Acid, Dopamine, and Acetaminophen), good stability with a linear response to glucose ranging from 0.1 mM to 0.6 mM concentration, and detection limits of 0.025 mM to 0.9 mM. Characterization of the electrodes was performed by scanning electron microscopy (FESEM and SEM). The electrochemical properties of the modified graphene electrodes were inspected by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and amperometry. PMID:26678700

  14. Accuracy Assessment of Using Rapid Prototyping Drill Templates for Atlantoaxial Screw Placement: A Cadaver Study.

    PubMed

    Guo, Shuai; Lu, Teng; Hu, Qiaolong; Yang, Baohui; He, Xijing; Li, Haopeng

    2016-01-01

    Purpose. To preliminarily evaluate the feasibility and accuracy of using rapid prototyping drill templates (RPDTs) for C1 lateral mass screw (C1-LMS) and C2 pedicle screw (C2-PS) placement. Methods. 23 formalin-fixed craniocervical cadaver specimens were randomly divided into two groups. In the conventional method group, intraoperative fluoroscopy was used to assist the screw placement. In the RPDT navigation group, specific RPDTs were constructed for each specimen and were used intraoperatively for screw placement navigation. The screw position, the operating time, and the fluoroscopy time for each screw placement were compared between the 2 groups. Results. Compared with the conventional method, the RPDT technique significantly increased the placement accuracy of the C2-PS (p < 0.05). In the axial plane, using RPDTs also significantly increased C1-LMS placement accuracy (p < 0.05). In the sagittal plane, although using RPDTs had a very high accuracy rate (100%) in C1-LMS placement, it was not statistically significant compared with the conventional method (p > 0.05). Moreover, the RPDT technique significantly decreased the operating and fluoroscopy times. Conclusion. Using RPDTs significantly increases the accuracy of C1-LMS and C2-PS placement while decreasing the screw placement time and the radiation exposure. Due to these advantages, this approach is worth promoting for use in the Harms technique.

  15. Porous titanium scaffolds fabricated using a rapid prototyping and powder metallurgy technique.

    PubMed

    Ryan, Garrett E; Pandit, Abhay S; Apatsidis, Dimitrios P

    2008-09-01

    One of the main issues in orthopaedic implant design is the fabrication of scaffolds that closely mimic the biomechanical properties of the surrounding bone. This research reports on a multi-stage rapid prototyping technique that was successfully developed to produce porous titanium scaffolds with fully interconnected pore networks and reproducible porosity and pore size. The scaffolds' porous characteristics were governed by a sacrificial wax template, fabricated using a commercial 3D-printer. Powder metallurgy processes were employed to generate the titanium scaffolds by filling around the wax template with titanium slurry. In the attempt to optimise the powder metallurgy technique, variations in slurry concentration, compaction pressure and sintering temperature were investigated. By altering the wax design template, pore sizes ranging from 200 to 400 microm were achieved. Scaffolds with porosities of 66.8 +/- 3.6% revealed compression strengths of 104.4+/-22.5 MPa in the axial direction and 23.5 +/- 9.6 MPa in the transverse direction demonstrating their anisotropic nature. Scaffold topography was characterised using scanning electron microscopy and microcomputed tomography. Three-dimensional reconstruction enabled the main architectural parameters such as pore size, interconnecting porosity, level of anisotropy and level of structural disorder to be determined. The titanium scaffolds were compared to their intended designs, as governed by their sacrificial wax templates. Although discrepancies in architectural parameters existed between the intended and the actual scaffolds, overall the results indicate that the porous titanium scaffolds have the properties to be potentially employed in orthopaedic applications.

  16. Rapid Prototyping of a Cyclic Olefin Copolymer Microfluidic Device for Automated Oocyte Culturing.

    PubMed

    Berenguel-Alonso, Miguel; Sabés-Alsina, Maria; Morató, Roser; Ymbern, Oriol; Rodríguez-Vázquez, Laura; Talló-Parra, Oriol; Alonso-Chamarro, Julián; Puyol, Mar; López-Béjar, Manel

    2017-01-01

    Assisted reproductive technology (ART) can benefit from the features of microfluidic technologies, such as the automation of time-consuming labor-intensive procedures, the possibility to mimic in vivo environments, and the miniaturization of the required equipment. To date, most of the proposed approaches are based on polydimethylsiloxane (PDMS) as platform substrate material due to its widespread use in academia, despite certain disadvantages, such as the elevated cost of mass production. Herein, we present a rapid fabrication process for a cyclic olefin copolymer (COC) monolithic microfluidic device combining hot embossing-using a low-temperature cofired ceramic (LTCC) master-and micromilling. The microfluidic device was suitable for trapping and maturation of bovine oocytes, which were further studied to determine their ability to be fertilized. Furthermore, another COC microfluidic device was fabricated to store sperm and assess its quality parameters over time. The study herein presented demonstrates a good biocompatibility of the COC when working with gametes, and it exhibits certain advantages, such as the nonabsorption of small molecules, gas impermeability, and low fabrication costs, all at the prototyping and mass production scale, thus taking a step further toward fully automated microfluidic devices in ART.

  17. Rapid Prototyping of a Cyclic Olefin Copolymer Microfluidic Device for Automated Oocyte Culturing.

    PubMed

    Berenguel-Alonso, Miguel; Sabés-Alsina, Maria; Morató, Roser; Ymbern, Oriol; Rodríguez-Vázquez, Laura; Talló-Parra, Oriol; Alonso-Chamarro, Julián; Puyol, Mar; López-Béjar, Manel

    2017-10-01

    Assisted reproductive technology (ART) can benefit from the features of microfluidic technologies, such as the automation of time-consuming labor-intensive procedures, the possibility to mimic in vivo environments, and the miniaturization of the required equipment. To date, most of the proposed approaches are based on polydimethylsiloxane (PDMS) as platform substrate material due to its widespread use in academia, despite certain disadvantages, such as the elevated cost of mass production. Herein, we present a rapid fabrication process for a cyclic olefin copolymer (COC) monolithic microfluidic device combining hot embossing-using a low-temperature cofired ceramic (LTCC) master-and micromilling. The microfluidic device was suitable for trapping and maturation of bovine oocytes, which were further studied to determine their ability to be fertilized. Furthermore, another COC microfluidic device was fabricated to store sperm and assess its quality parameters over time. The study herein presented demonstrates a good biocompatibility of the COC when working with gametes, and it exhibits certain advantages, such as the nonabsorption of small molecules, gas impermeability, and low fabrication costs, all at the prototyping and mass production scale, thus taking a step further toward fully automated microfluidic devices in ART.

  18. Rapid prototyping of silicon structures by aid of laser and abrasive-jet machining

    NASA Astrophysics Data System (ADS)

    Kruusing, Arvi; Leppaevuori, Seppo; Uusimaki, Antti; Uusimaki, Matti

    1999-03-01

    Rapid prototyping of silicon microstructures for fluidic devices using laser machining in water and abrasive-jet machining through mask is described. For laser machining a Q-switched 1-2 W 1 kHz pulsed Nd:YAG laser beam and 60 mJ XeCl excimer laser beam were used. The laser beam was scanned along the silicon surface at speeds 0.1-2 mm/s. Using excimer laser, the silicon nitride layer was patterned for subsequent chemical etching. Nd:YAG laser was used for fabrication of cavities and channels of depth down to 200 micrometers . Comparison of Nd:YAG laser machining of silicon in air and in water has been performed. Machining in water yields more even surfaces and there is no debris. By abrasive jet of velocity approximately 200 m/s and abrasive feed rate of 0.4 g/s, the silicon was eroded at speed of 40 micrometers /min. Several masking materials were compared, whereby a styrene based glue was found to have the best abrasion resistivity. The polymer masks were spun on the surface and patterned by excimer laser point or by knife. The described fabrication methods were used for making the fluid channels and chambers in silicon and for releasing silicon nitride and oxide films.

  19. Deep proton writing with 12 MeV protons for rapid prototyping of microstructures in polymethylmethacrylate

    NASA Astrophysics Data System (ADS)

    Ebraert, Evert; Gökçe, Berkcan; Van Vlierberghe, Sandra; Vervaeke, Michael; Meyer, Pascal; Guttmann, Markus; Dubruel, Peter; Thienpont, Hugo; Van Erps, Jürgen

    2016-10-01

    Deep proton writing (DPW) is a fabrication technology developed for the rapid prototyping of polymer microstructures. We use polymethylmethacrylate (PMMA) substrates, which act as a positive resist, for irradiation with a collimated 12-MeV energy proton beam. Using 12 MeV enables the irradiation of increasingly thick PMMA substrates with less conicity of the sidewalls compared to the lower energies used in previous work. A microhole of 47.7 μm diameter over a depth of 1 mm is achieved, leading to a maximum aspect ratio of 21∶1. The sidewalls of the irradiated structures show a slightly conical shape and their root-mean-square surface roughness is lower than 50 nm averaged over 72 measured areas of 56 μm×44 μm. This means that DPW components have optical surface quality sidewalls for wavelengths larger than 400 nm. Based on the trade-off among the sidewall roughness, conicity, and the development time, we determine that the optimal proton fluence for 12-MeV DPW in PMMA is 7.75×106 μm-2. Finally, we discuss some high aspect ratio microstructures with optical surface quality that were created with DPW to be used for a myriad of applications, such as micromirrors, microlenses, optofluidic devices, and high-precision alignment structures for single-mode optical fiber connectors.

  20. Rapid Prototyping Technique for the Fabrication of Millifluidic Devices for Polymer Formulations

    NASA Astrophysics Data System (ADS)

    Cabral, Joao; Harrison, Christopher; Eric, Amis; Karim, Alamgir

    2003-03-01

    We describe a rapid prototyping technique for the fabrication of 600 micron deep fluidic channels in a solvent-resistant polymeric matrix. Using a conventional illumination source, a laser-jet printed mask, and a commercially available thioelene-based adhesive, we demonstrate the fabrication of fluidic channels which are impervious to a wide range of solvents. The fabrication of channels with this depth by conventional lithography would be both challenging and time-consuming. We demonstrate two lithography methods: one which fabricates channels sealed between glass plates (closed face) and one which fabricates structures on a single plate (open-faced). Furthermore, we demonstrate that this technology can be used to fabricate channels with a depth which varies linearly with distance. The latter is completely compatible with silicone replication technniques. Additionally, we demonstrate that siloxane-based elastomer molds of these channels can be readily made for aqueous applications. Applications to on-line phase mapping of polymer solutions (PEO-Water-Salt) and off line phase separation studies will be discussed.

  1. Fabrication of topologically complex three-dimensional microfluidic systems in PDMS by rapid prototyping.

    PubMed

    Anderson, J R; Chiu, D T; Jackman, R J; Cherniavskaya, O; McDonald, J C; Wu, H; Whitesides, S H; Whitesides, G M

    2000-07-15

    This paper describes a procedure for making topologically complex three-dimensional microfluidic channel systems in poly(dimethylsiloxane) (PDMS). This procedure is called the "membrane sandwich" method to suggest the structure of the final system: a thin membrane having channel structures molded on each face (and with connections between the faces) sandwiched between two thicker, flat slabs that provide structural support. Two "masters" are fabricated by rapid prototyping using two-level photolithography and replica molding. They are aligned face to face, under pressure, with PDMS prepolymer between them. The PDMS is cured thermally. The masters have complementary alignment tracks, so registration is straightforward. The resulting, thin PDMS membrane can be transferred and sealed to another membrane or slab of PDMS by a sequence of steps in which the two masters are removed one at a time; these steps take place without distortion of the features. This method can fabricate a membrane containing a channel that crosses over and under itself, but does not intersect itself and, therefore, can be fabricated in the form of any knot. It follows that this method can generate topologically complex microfluidic systems; this capability is demonstrated by the fabrication of a "basketweave" structure. By filling the channels and removing the membrane, complex microstructures can be made. Stacking and sealing more than one membrane allows even more complicated geometries than are possible in one membrane. A square coiled channel that surrounds, but does not connect to, a straight channel illustrates this type of complexity.

  2. Direct rapid prototyping of PDMS from a photomask film for micropatterning of biomolecules and cells.

    PubMed

    Hwang, Hyundoo; Kang, Gyumin; Yeon, Ju Hun; Nam, Yoonkey; Park, Je-Kyun

    2009-01-07

    The soft lithographic technique is a collection of simple and cost-effective patterning techniques which applies an elastomeric stamp to transfer a nano/micro-scale pattern. Patterning biological materials using soft lithography provides procedurally simple control of the surface chemistry and the cell environments. However, conventional methods for generating microstructures on a substrate require expensive clean room facilities and skillful training. Here we report a simple and inexpensive clean-room free process using a conventional photomask film as a master to fabricate elastomeric stamps or microfluidic channels. This ultra rapid prototyping technique was applied to print FITC labeled poly-L-lysine with a 10 microm feature size on a glass substrate using soft lithographic processes, such as micro-contact printing and micromolding in capillaries, for patterning human hepatocellular carcinoma cells, human skin fibroblasts and hippocampal neurons from E-18 Sprague-Dawley rat. This novel technique using a photomask film as a master would be very useful 'hands-on' tool for the generation of micro-patterned chemical or biological assays using cells and proteins.

  3. Rapid Prototyping of Poly(methyl methacrylate) Microfluidic Systems Using Solvent Imprinting and Bonding

    PubMed Central

    Sun, Xiuhua; Peeni, Bridget A.; Yang, Weichun; Becerril, Hector A.

    2011-01-01

    We have developed a method for rapid prototyping of hard polymer microfluidic systems using solvent imprinting and bonding. We investigated the applicability of patterned SU-8 photoresist on glass as an easily fabricated template for solvent imprinting. Poly(methyl methacrylate) (PMMA) exposed to acetonitrile for 2 min then had an SU-8 template pressed into the surface for 10 min, which provided appropriately imprinted channels and a suitable surface for bonding. After a PMMA cover plate had also been exposed to acetonitrile for 2 min, the imprinted and top PMMA pieces could be bonded together at room temperature with appropriate pressure. The total fabrication time was less than 15 min. Under the optimized fabrication conditions, nearly 30 PMMA chips could be replicated using a single patterned SU-8 master with high chip-to-chip reproducibility. Relative standard deviations were 2.3% and 5.4% for the widths and depths of the replicated channels, respectively. Fluorescently labeled amino acid and peptide mixtures were baseline separated using these PMMA microchips in <15 s. Theoretical plate numbers in excess of 5000 were obtained for a ~3 cm separation distance, and the migration time relative standard deviation for an amino acid peak was 1.5% for intra-day and 2.2% for inter-day analysis. This new solvent imprinting and bonding approach significantly simplifies the process for fabricating microfluidic structures in hard polymers such as PMMA. PMID:17466320

  4. Three-dimensional bioactive glass implants fabricated by rapid prototyping based on CO(2) laser cladding.

    PubMed

    Comesaña, R; Lusquiños, F; Del Val, J; López-Álvarez, M; Quintero, F; Riveiro, A; Boutinguiza, M; de Carlos, A; Jones, J R; Hill, R G; Pou, J

    2011-09-01

    Three-dimensional bioactive glass implants were produced by rapid prototyping based on laser cladding without using moulds. CO(2) laser radiation was employed to melt 45S5 and S520 bioactive glass particles and to deposit the material layer by layer following a desired geometry. Controlled thermal input and cooling rate by fine tuning of the processing parameters allowed the production of crack-free fully dense implants. Microstructural characterization revealed chemical composition stability, but crystallization during processing was extensive when 45S5 bioactive glass was used. Improved results were obtained using the S520 bioactive glass, which showed limited surface crystallization due to an expanded sintering window (the difference between the glass transition temperature and crystallization onset temperature). Ion release from the S520 implants in Tris buffer was similar to that of amorphous 45S5 bioactive glass prepared by casting in graphite moulds. Laser processed S520 scaffolds were not cytotoxic in vitro when osteoblast-like MC3T3-E1 cells were cultured with the dissolution products of the glasses; and the MC3T3-E1 cells attached and spread well when cultured on the surface of the materials.

  5. Rapid prototyping: porous titanium alloy scaffolds produced by selective laser melting for bone tissue engineering.

    PubMed

    Warnke, Patrick H; Douglas, Timothy; Wollny, Patrick; Sherry, Eugene; Steiner, Martin; Galonska, Sebastian; Becker, Stephan T; Springer, Ingo N; Wiltfang, Jörg; Sivananthan, Sureshan

    2009-06-01

    Selective laser melting (SLM), a method used in the nuclear, space, and racing industries, allows the creation of customized titanium alloy scaffolds with highly defined external shape and internal structure using rapid prototyping as supporting external structures within which bone tissue can grow. Human osteoblasts were cultured on SLM-produced Ti6Al4V mesh scaffolds to demonstrate biocompatibility using scanning electron microscopy (SEM), fluorescence microscopy after cell vitality staining, and common biocompatibility tests (lactate dihydrogenase (LDH), 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT), 5-bromo-2-deoxyuridine (BrdU), and water soluble tetrazolium (WST)). Cell occlusion of pores of different widths (0.45-1.2 mm) was evaluated. Scaffolds were tested for resistance to compressive force. SEM investigations showed osteoblasts with well-spread morphology and multiple contact points. Cell vitality staining and biocompatibility tests confirmed osteoblast vitality and proliferation on the scaffolds. Pore overgrowth increased during 6 weeks' culture at pore widths of 0.45 and 0.5 mm, and in the course of 3 weeks for pore widths of 0.55, 0.6, and 0.7 mm. No pore occlusion was observed on pores of width 0.9-1.2 mm. Porosity and maximum compressive load at failure increased and decreased with increasing pore width, respectively. In summary, the scaffolds are biocompatible, and pore width influences pore overgrowth, resistance to compressive force, and porosity.

  6. Rapid prototyping of electrochromatography chips for improved two-photon excited fluorescence detection.

    PubMed

    Hackl, Claudia; Beyreiss, Reinhild; Geissler, David; Jezierski, Stefan; Belder, Detlev

    2014-04-15

    In the present study, we introduce two-photon excitation at 532 nm for label-free fluorescence detection in chip electrochromatography. Two-photon excitation at 532 nm offers a promising alternative to one-photon excitation at 266 nm, as it enables the use of economic chip materials instead of fused silica. In order to demonstrate these benefits, one-photon and two-photon induced fluorescence detection are compared in different chip layouts and materials with respect to the achievable sensitivity in the detection of polycyclic aromatic hydrocarbons (PAHs). Customized chromatography chips with cover or bottom slides of different material and thickness are produced by means of a rapid prototyping method based on liquid-phase lithography. The design of thin bottom chips (180 μm) enables the use of high-performance immersion objectives with low working distances, which allows one to exploit the full potential of two-photon excitation for a sensitive detection. The developed method is applied for label-free analysis of PAHs separated on a polymer monolith inside polymer glass sandwich chips made from fused silica or soda-lime glass. The obtained limits of detection range from 40 nM to 1.95 μM, with similar sensitivities in fused silica thin bottom chips for one-photon and two-photon excitation. In deep-UV non- or less-transparent devices two-photon excitation is mandatory for label-free detection of aromatics with high sensitivity.

  7. Prototyping disposable electrophoresis microchips with electrochemical detection using rapid marker masking and laminar flow etching.

    PubMed

    Manica, Drew P; Ewing, Andrew G

    2002-11-01

    Two novel methods are described for the fabrication of components for microchip capillary electrophoresis with electrochemical detection (microchip CEEC) on glass substrates. First, rapid marker masking is introduced as a completely nonphotolithographic method of patterning and fabricating integrated thin-film metal electrodes onto a glass substrate. The process involves applying the pattern directly onto the metal layer with a permanent marker that masks the ensuing chemical etch. The method is characterized, and the performance of the resulting electrode is evaluated using catecholamines. The response compares well with photolithographically defined electrodes and exhibits detection limits of 648 nM and 1.02 microM for dopamine and catechol, respectively. Second, laminar flow etching is introduced as a partially nonphotolithographic method of replicating channel networks onto glass substrates. The replication process involves applying a poly(dimethylsiloxane) (PDMS) mold of the channel network onto a slide coated with a sacrificial metal layer and then pulling solutions of metal etchants through the channels to transfer the pattern onto the sacrificial layer. The method is tested, and prototype channel networks are shown. These methods serve to overcome the time and cost involved in fabricating glass-based microchips, thereby making the goal of a disposable high performance lab-on-a-chip more attainable.

  8. A platform for rapid prototyping of synthetic gene networks in mammalian cells

    PubMed Central

    Duportet, Xavier; Wroblewska, Liliana; Guye, Patrick; Li, Yinqing; Eyquem, Justin; Rieders, Julianne; Rimchala, Tharathorn; Batt, Gregory; Weiss, Ron

    2014-01-01

    Mammalian synthetic biology may provide novel therapeutic strategies, help decipher new paths for drug discovery and facilitate synthesis of valuable molecules. Yet, our capacity to genetically program cells is currently hampered by the lack of efficient approaches to streamline the design, construction and screening of synthetic gene networks. To address this problem, here we present a framework for modular and combinatorial assembly of functional (multi)gene expression vectors and their efficient and specific targeted integration into a well-defined chromosomal context in mammalian cells. We demonstrate the potential of this framework by assembling and integrating different functional mammalian regulatory networks including the largest gene circuit built and chromosomally integrated to date (6 transcription units, 27kb) encoding an inducible memory device. Using a library of 18 different circuits as a proof of concept, we also demonstrate that our method enables one-pot/single-flask chromosomal integration and screening of circuit libraries. This rapid and powerful prototyping platform is well suited for comparative studies of genetic regulatory elements, genes and multi-gene circuits as well as facile development of libraries of isogenic engineered cell lines. PMID:25378321

  9. Rapid Prototyping of a High Sensitivity Graphene Based Glucose Sensor Strip.

    PubMed

    Tehrani, Farshad; Reiner, Lisa; Bavarian, Behzad

    2015-01-01

    A rapid prototyping of an inexpensive, disposable graphene and copper nanocomposite sensor strip using polymeric flexible substrate for highly sensitive and selective nonenzymatic glucose detection has been developed and tested for direct oxidization of glucose. The CuNPs were electrochemically deposited on to the graphene sheets to improve electron transfer rates and to enhance electrocatalytic activity toward glucose. The graphene based electrode with CuNPs demonstrated a high degree of sensitivity (1101.3 ± 56 μA/mM.cm2), excellent selectivity (without an interference with Ascorbic Acid, Uric Acid, Dopamine, and Acetaminophen), good stability with a linear response to glucose ranging from 0.1 mM to 0.6 mM concentration, and detection limits of 0.025 mM to 0.9 mM. Characterization of the electrodes was performed by scanning electron microscopy (FESEM and SEM). The electrochemical properties of the modified graphene electrodes were inspected by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and amperometry.

  10. Extrusion based rapid prototyping technique: an advanced platform for tissue engineering scaffold fabrication.

    PubMed

    Hoque, M Enamul; Chuan, Y Leng; Pashby, Ian

    2012-02-01

    Advances in scaffold design and fabrication technology have brought the tissue engineering field stepping into a new era. Conventional techniques used to develop scaffolds inherit limitations, such as lack of control over the pore morphology and architecture as well as reproducibility. Rapid prototyping (RP) technology, a layer-by-layer additive approach offers a unique opportunity to build complex 3D architectures overcoming those limitations that could ultimately be tailored to cater for patient-specific applications. Using RP methods, researchers have been able to customize scaffolds to mimic the biomechanical properties (in terms of structural integrity, strength, and microenvironment) of the organ or tissue to be repaired/replaced quite closely. This article provides intensive description on various extrusion based scaffold fabrication techniques and review their potential utility for TE applications. The extrusion-based technique extrudes the molten polymer as a thin filament through a nozzle onto a platform layer-by-layer and thus building 3D scaffold. The technique allows full control over pore architecture and dimension in the x- and y- planes. However, the pore height in z-direction is predetermined by the extruding nozzle diameter rather than the technique itself. This review attempts to assess the current state and future prospects of this technology.

  11. Using CamiTK for rapid prototyping of interactive computer assisted medical intervention applications.

    PubMed

    Promayon, Emmanuel; Fouard, Céline; Bailet, Mathieu; Deram, Aurélien; Fiard, Gaëlle; Hungr, Nikolai; Luboz, Vincent; Payan, Yohan; Sarrazin, Johan; Saubat, Nicolas; Selmi, Sonia Yuki; Voros, Sandrine; Cinquin, Philippe; Troccaz, Jocelyne

    2013-01-01

    Computer Assisted Medical Intervention (CAMI hereafter) is a complex multi-disciplinary field. CAMI research requires the collaboration of experts in several fields as diverse as medicine, computer science, mathematics, instrumentation, signal processing, mechanics, modeling, automatics, optics, etc. CamiTK is a modular framework that helps researchers and clinicians to collaborate together in order to prototype CAMI applications by regrouping the knowledge and expertise from each discipline. It is an open-source, cross-platform generic and modular tool written in C++ which can handle medical images, surgical navigation, biomedicals simulations and robot control. This paper presents the Computer Assisted Medical Intervention ToolKit (CamiTK) and how it is used in various applications in our research team.

  12. Numerical study of similarity in prototype and model pumped turbines

    NASA Astrophysics Data System (ADS)

    Li, Z. J.; Wang, Z. W.; Bi, H. L.

    2014-03-01

    Similarity study of prototype and model pumped turbines are performed by numerical simulation and the partial discharge case is analysed in detail. It is found out that in the RSI (rotor-stator interaction) region where the flow is convectively accelerated with minor flow separation, a high level of similarity in flow patterns and pressure fluctuation appear with relative pressure fluctuation amplitude of model turbine slightly higher than that of prototype turbine. As for the condition in the runner where the flow is convectively accelerated with severe separation, similarity fades substantially due to different topology of flow separation and vortex formation brought by distinctive Reynolds numbers of the two turbines. In the draft tube where the flow is diffusively decelerated, similarity becomes debilitated owing to different vortex rope formation impacted by Reynolds number. It is noted that the pressure fluctuation amplitude and characteristic frequency of model turbine are larger than those of prototype turbine. The differences in pressure fluctuation characteristics are discussed theoretically through dimensionless Navier-Stokes equation. The above conclusions are all made based on simulation without regard to the penstock response and resonance.

  13. Application of the rapid prototyping technique to design a customized temporomandibular joint used to treat temporomandibular ankylosis

    PubMed Central

    Chaware, Suresh M.; Bagaria, Vaibhav; Kuthe, Abhay

    2009-01-01

    Anthropometric variations in humans make it difficult to replace a temporomandibular joint (TMJ), successfully using a standard “one-size-fits-all” prosthesis. The case report presents a unique concept of total TMJ replacement with customized and modified TMJ prosthesis, which is cost-effective and provides the best fit for the patient. The process involved in designing and modifications over the existing prosthesis are also described. A 12-year- old female who presented for treatment of left unilateral TMJ ankylosis underwent the surgery for total TMJ replacement. A three-dimensional computed tomography (CT) scan suggested features of bony ankylosis of left TMJ. CT images were converted to a sterolithographic model using CAD software and a rapid prototyping machine. A process of rapid manufacturing was then used to manufacture the customized prosthesis. Postoperative recovery was uneventful, with an improvement in mouth opening of 3.5 cm and painless jaw movements. Three years postsurgery, the patient is pain-free, has a mouth opening of about 4.0 cm and enjoys a normal diet. The postoperative radiographs concur with the excellent clinical results. The use of CAD/CAM technique to design the custom-made prosthesis, using orthopaedically proven structural materials, significantly improves the predictability and success rates of TMJ replacement surgery. PMID:19881026

  14. Rapid prototyping 3D virtual world interfaces within a virtual factory environment

    NASA Technical Reports Server (NTRS)

    Kosta, Charles Paul; Krolak, Patrick D.

    1993-01-01

    On-going work into user requirements analysis using CLIPS (NASA/JSC) expert systems as an intelligent event simulator has led to research into three-dimensional (3D) interfaces. Previous work involved CLIPS and two-dimensional (2D) models. Integral to this work was the development of the University of Massachusetts Lowell parallel version of CLIPS, called PCLIPS. This allowed us to create both a Software Bus and a group problem-solving environment for expert systems development. By shifting the PCLIPS paradigm to use the VEOS messaging protocol we have merged VEOS (HlTL/Seattle) and CLIPS into a distributed virtual worlds prototyping environment (VCLIPS). VCLIPS uses the VEOS protocol layer to allow multiple experts to cooperate on a single problem. We have begun to look at the control of a virtual factory. In the virtual factory there are actors and objects as found in our Lincoln Logs Factory of the Future project. In this artificial reality architecture there are three VCLIPS entities in action. One entity is responsible for display and user events in the 3D virtual world. Another is responsible for either simulating the virtual factory or communicating with the real factory. The third is a user interface expert. The interface expert maps user input levels, within the current prototype, to control information for the factory. The interface to the virtual factory is based on a camera paradigm. The graphics subsystem generates camera views of the factory on standard X-Window displays. The camera allows for view control and object control. Control or the factory is accomplished by the user reaching into the camera views to perform object interactions. All communication between the separate CLIPS expert systems is done through VEOS.

  15. Validation of thermal models for a prototypical MEMS thermal actuator.

    SciTech Connect

    Gallis, Michail A.; Torczynski, John Robert; Piekos, Edward Stanley; Serrano, Justin Raymond; Gorby, Allen D.; Phinney, Leslie Mary

    2008-09-01

    This report documents technical work performed to complete the ASC Level 2 Milestone 2841: validation of thermal models for a prototypical MEMS thermal actuator. This effort requires completion of the following task: the comparison between calculated and measured temperature profiles of a heated stationary microbeam in air. Such heated microbeams are prototypical structures in virtually all electrically driven microscale thermal actuators. This task is divided into four major subtasks. (1) Perform validation experiments on prototypical heated stationary microbeams in which material properties such as thermal conductivity and electrical resistivity are measured if not known and temperature profiles along the beams are measured as a function of electrical power and gas pressure. (2) Develop a noncontinuum gas-phase heat-transfer model for typical MEMS situations including effects such as temperature discontinuities at gas-solid interfaces across which heat is flowing, and incorporate this model into the ASC FEM heat-conduction code Calore to enable it to simulate these effects with good accuracy. (3) Develop a noncontinuum solid-phase heat transfer model for typical MEMS situations including an effective thermal conductivity that depends on device geometry and grain size, and incorporate this model into the FEM heat-conduction code Calore to enable it to simulate these effects with good accuracy. (4) Perform combined gas-solid heat-transfer simulations using Calore with these models for the experimentally investigated devices, and compare simulation and experimental temperature profiles to assess model accuracy. These subtasks have been completed successfully, thereby completing the milestone task. Model and experimental temperature profiles are found to be in reasonable agreement for all cases examined. Modest systematic differences appear to be related to uncertainties in the geometric dimensions of the test structures and in the thermal conductivity of the

  16. Rapid Model Fabrication and Testing for Aerospace Vehicles

    NASA Technical Reports Server (NTRS)

    Buck, Gregory M.

    2000-01-01

    Advanced methods for rapid fabrication and instrumentation of hypersonic wind tunnel models are being developed and evaluated at NASA Langley Research Center. Rapid aeroheating model fabrication and measurement techniques using investment casting of ceramic test models and thermographic phosphors are reviewed. More accurate model casting techniques for fabrication of benchmark metal and ceramic test models are being developed using a combination of rapid prototype patterns and investment casting. White light optical scanning is used for coordinate measurements to evaluate the fabrication process and verify model accuracy to +/- 0.002 inches. Higher-temperature (<210C) luminescent coatings are also being developed for simultaneous pressure and temperature mapping, providing global pressure as well as global aeroheating measurements. Together these techniques will provide a more rapid and complete experimental aerodynamic and aerothermodynamic database for future aerospace vehicles.

  17. Virtual modelling of novel applicator prototypes for cervical cancer brachytherapy

    PubMed Central

    Hudej, Robert; Al-Hammadi, Noora; Segedin, Barbara

    2016-01-01

    Abstract Background Standard applicators for cervical cancer Brachytherapy (BT) do not always achieve acceptable balance between target volume and normal tissue irradiation. We aimed to develop an innovative method of Target-volume Density Mapping (TDM) for modelling of novel applicator prototypes with optimal coverage characteristics. Patients and methods. Development of Contour-Analysis Tool 2 (CAT-2) software for TDM generation was the core priority of our task group. Main requests regarding software functionalities were formulated and guided the coding process. Software validation and accuracy check was performed using phantom objects. Concepts and terms for standardized workflow of TDM post-processing and applicator development were introduced. Results CAT-2 enables applicator-based co-registration of Digital Imaging and Communications in Medicine (DICOM) structures from a sample of cases, generating a TDM with pooled contours in applicator-eye-view. Each TDM voxel is assigned a value, corresponding to the number of target contours encompassing that voxel. Values are converted to grey levels and transformed to DICOM image, which is transported to the treatment planning system. Iso-density contours (IDC) are generated as lines, connecting voxels with same grey levels. Residual Volume at Risk (RVR) is created for each IDC as potential volume that could contain organs at risk. Finally, standard and prototype applicators are applied on the TDM and virtual dose planning is performed. Dose volume histogram (DVH) parameters are recorded for individual IDC and RVR delineations and characteristic curves generated. Optimal applicator configuration is determined in an iterative manner based on comparison of characteristic curves, virtual implant complexities and isodose distributions. Conclusions Using the TDM approach, virtual applicator prototypes capable of conformal coverage of any target volume, can be modelled. Further systematic assessment, including studies on

  18. Application of Rapid Prototyping to the Investment Casting of Test Hardware (MSFC Center Director's Discretionary Fund Final Report, Project No. 98-08)

    NASA Technical Reports Server (NTRS)

    Cooper, K. G.; Wells, D.

    2000-01-01

    Investment casting masters of a selected propulsion hardware component, a fuel pump housing, were rapid prototyped on the several processes in-house, along with the new Z-Corp process acquired through this project. Also, tensile samples were prototyped and cast using the same significant parameters. The models were then shelled in-house using a commercial grade zircon-based slurry and stucco technique. Next, the shelled models were fired and cast by our in-house foundry contractor (IITRI), with NASA-23, a commonly used test hardware metal. The cast models are compared by their surface finish and overall appearance (i.e., the occurrence of pitting, warping, etc.), as well as dimensional accuracy.

  19. Development of a prototype lateral flow immunoassay (LFI) for the rapid diagnosis of melioidosis.

    PubMed

    Houghton, Raymond L; Reed, Dana E; Hubbard, Mark A; Dillon, Michael J; Chen, Hongjing; Currie, Bart J; Mayo, Mark; Sarovich, Derek S; Theobald, Vanessa; Limmathurotsakul, Direk; Wongsuvan, Gumphol; Chantratita, Narisara; Peacock, Sharon J; Hoffmaster, Alex R; Duval, Brea; Brett, Paul J; Burtnick, Mary N; Aucoin, David P

    2014-03-01

    Burkholderia pseudomallei is a soil-dwelling bacterium and the causative agent of melioidosis. Isolation of B. pseudomallei from clinical samples is the "gold standard" for the diagnosis of melioidosis; results can take 3-7 days to produce. Alternatively, antibody-based tests have low specificity due to a high percentage of seropositive individuals in endemic areas. There is a clear need to develop a rapid point-of-care antigen detection assay for the diagnosis of melioidosis. Previously, we employed In vivo Microbial Antigen Discovery (InMAD) to identify potential B. pseudomallei diagnostic biomarkers. The B. pseudomallei capsular polysaccharide (CPS) and numerous protein antigens were identified as potential candidates. Here, we describe the development of a diagnostic immunoassay based on the detection of CPS. Following production of a CPS-specific monoclonal antibody (mAb), an antigen-capture immunoassay was developed to determine the concentration of CPS within a panel of melioidosis patient serum and urine samples. The same mAb was used to produce a prototype Active Melioidosis Detect Lateral Flow Immunoassay (AMD LFI); the limit of detection of the LFI for CPS is comparable to the antigen-capture immunoassay (∼0.2 ng/ml). The analytical reactivity (inclusivity) of the AMD LFI was 98.7% (76/77) when tested against a large panel of B. pseudomallei isolates. Analytical specificity (cross-reactivity) testing determined that 97.2% of B. pseudomallei near neighbor species (35/36) were not reactive. The non-reactive B. pseudomallei strain and the reactive near neighbor strain can be explained through genetic sequence analysis. Importantly, we show the AMD LFI is capable of detecting CPS in a variety of patient samples. The LFI is currently being evaluated in Thailand and Australia; the focus is to optimize and validate testing procedures on melioidosis patient samples prior to initiation of a large, multisite pre-clinical evaluation.

  20. [Research and development of computer aided design and rapid prototyping technology for complete denture].

    PubMed

    Sun, Yu-chun; Lü, Pei-jun; Wang, Yong; Han, Jing-yun; Zhao, Jian-jiang

    2007-06-01

    To explore a computer aided design (CAD) and rapid prototyping (RP) approach for fabrication of complete denture and to develop relevant programs for implementing it. Automatic crossing section scanner was used to scan artificial teeth and 3D graphic database of artificial teeth that could be aligned with parameters was established. A 3D laser scanner was used to scan upper and lower edentulous jaw casts and rims made in clinic. The vertical and horizontal relations were recorded before scanning with a patient instrument. Based on Imageware 11, tooth-arrangement curves, coordinate system, and landmark points for positioning were created, and construction cure and shape-controlling curve for base plate were constructed as well. Three-dimensional integrated design of complete denture, including artificial tooth automatic arrangement, aesthetic and individualized design of base plate, and artificial gingival, were finished. The programs were developed following the approach and the CAD platform was established. The virtual molds of complete dentures were constructed according to the above data in design and RP technology was used to make the plaster molds. Finally, the teeth were inserted and the complete denture was finished by dental technician. The approach for the complete denture CAD/RP was confirmed and the CAD software platform was developed. A complete denture was manufactured. The rules for complete denture in textbooks were expressed in design process with the CAD program developed by researcher. The 3D data of rims were utilized in design so that the digital, intelligentized and individualized design and manufacture process for complete denture was implemented.

  1. Reconstruction of comminuted long-bone fracture using CF/CPC scaffolds manufactured by rapid prototyping

    PubMed Central

    Huang, Sheng-Li; Wen, Bo; Bian, Wei-Guo; Yan, Hong-Wei

    2012-01-01

    Summary Background Stabilization and bone healing of fractures in weight-bearing long bones are challenging. This study was conducted to evaluate the effect of a scaffold composed of chitosan fiber and calcium phosphate ceramics (CF/CPC scaffold) on stability and fracture repair in weight-bearing long bones. Material/Methods Comminuted fractures of paired radiuses were created in 36 healthy, mature dogs. The left radius of each dog was classified in the experimental group and treated with CF/CPC scaffold, and the right one was not filled, and was used as a blank control. Of the 12 animals in each group that were killed at week 4, 8, and 12 after the operation, 6 were used for histological analysis, and the other 6 used were for biomechanical studies. Both radiuses from each animal were dissected free and stored for these analyses. All the animals underwent X-ray radiograph pre- and post-operatively. Computer-aided rapid-prototyping technologies were adopted for the fabrication of three-dimensional scaffolds with precise geometric control. Results X-ray showed that the bone fracture area in the experimental group was filled with callus at week 12 after surgery. Histological examination detected slow resorption of the cement and new bone formation since week 4. At week 12, the scaffold material partially degraded and was still present in all specimens. Mechanical testing revealed that the failure strength of the radiuses treated with CF/CPC scaffolds was about 3 times that of the radiuses without implanted scaffolds. Conclusions The effect of using CF/CPC scaffold in treating comminuted weight-bearing long bone fractures is satisfactory. PMID:23111734

  2. Development of a Prototype Lateral Flow Immunoassay (LFI) for the Rapid Diagnosis of Melioidosis

    PubMed Central

    Houghton, Raymond L.; Reed, Dana E.; Hubbard, Mark A.; Dillon, Michael J.; Chen, Hongjing; Currie, Bart J.; Mayo, Mark; Sarovich, Derek S.; Theobald, Vanessa; Limmathurotsakul, Direk; Wongsuvan, Gumphol; Chantratita, Narisara; Peacock, Sharon J.; Hoffmaster, Alex R.; Duval, Brea; Brett, Paul J.; Burtnick, Mary N.; AuCoin, David P.

    2014-01-01

    Burkholderia pseudomallei is a soil-dwelling bacterium and the causative agent of melioidosis. Isolation of B. pseudomallei from clinical samples is the “gold standard” for the diagnosis of melioidosis; results can take 3–7 days to produce. Alternatively, antibody-based tests have low specificity due to a high percentage of seropositive individuals in endemic areas. There is a clear need to develop a rapid point-of-care antigen detection assay for the diagnosis of melioidosis. Previously, we employed In vivo Microbial Antigen Discovery (InMAD) to identify potential B. pseudomallei diagnostic biomarkers. The B. pseudomallei capsular polysaccharide (CPS) and numerous protein antigens were identified as potential candidates. Here, we describe the development of a diagnostic immunoassay based on the detection of CPS. Following production of a CPS-specific monoclonal antibody (mAb), an antigen-capture immunoassay was developed to determine the concentration of CPS within a panel of melioidosis patient serum and urine samples. The same mAb was used to produce a prototype Active Melioidosis Detect Lateral Flow Immunoassay (AMD LFI); the limit of detection of the LFI for CPS is comparable to the antigen-capture immunoassay (∼0.2 ng/ml). The analytical reactivity (inclusivity) of the AMD LFI was 98.7% (76/77) when tested against a large panel of B. pseudomallei isolates. Analytical specificity (cross-reactivity) testing determined that 97.2% of B. pseudomallei near neighbor species (35/36) were not reactive. The non-reactive B. pseudomallei strain and the reactive near neighbor strain can be explained through genetic sequence analysis. Importantly, we show the AMD LFI is capable of detecting CPS in a variety of patient samples. The LFI is currently being evaluated in Thailand and Australia; the focus is to optimize and validate testing procedures on melioidosis patient samples prior to initiation of a large, multisite pre-clinical evaluation. PMID:24651568

  3. Mechanical properties and cytotoxicity of a resorbable bioactive implant prepared by rapid prototyping technique.

    PubMed

    El-Ghannam, Ahmed; Hart, Amanda; White, Dean; Cunningham, Larry

    2013-10-01

    Bioceramic processing using rapid prototyping technique (RPT) results in a fragile device that requires thermal treatment to improve the mechanical properties. This investigation evaluates the effect of thermal treatment on the mechanical, porosity, and bioactivity properties as well as the cytotoxicity of a porous silica-calcium phosphate nanocomposite (SCPC) implant prepared by RPT. Porous SCPC implant was subject to 3-h treatment at 800°C, 850°C, or 900°C. The compressive strength (s) and modulus of elasticity (E) were doubled when the sintering temperature is raised from 850 to 900°C measuring (s = 15.326 ± 2.95 MPa and E = 1095 ± 164 MPa) after the later treatment. The significant increase in mechanical properties takes place with minimal changes in the surface area and the percentage of pores in the range 1-356 μm. The SCPC implant prepared at 900°C was loaded with rh-BMP-2 and grafted into a segmental defect in the rabbit ulna. Histology analyses showed highly vascularized bone formation inside the defect. Histopathological analyses of the liver, spleen, kidney, heart, and the lung of rabbits grafted with and without SCPC demonstrated healthy tissues with no signs of toxicity or morphology alterations. Results of the study suggest that it is possible to engineering the mechanical properties of the SCPC implant without compromising its bioactivity. The enhanced bone formation inside the porous SCPC facilitated cell-mediated graft resorption and prohibited any accumulation of the material in the body organs. Copyright © 2013 Wiley Periodicals, Inc., a Wiley Company.

  4. Cervical screw placement using rapid prototyping drill templates for navigation: a literature review.

    PubMed

    Lu, Teng; Liu, Chao; Dong, Jun; Lu, Meng; Li, Haopeng; He, Xijing

    2016-12-01

    Due to the high screw malposition rate and the potential risk of neurovascular injury in cervical fixation surgeries, guided tools, mainly computer-assisted surgery navigation systems and rapid prototyping drill templates (RPDTs) have increasingly been developed to help surgeons improve screw placement accuracy. Although RPDTs have been used in cervical surgeries for almost 2 decades, no specific review has been performed detailing the state of this technique. Thus, in the current review, we fully discuss the status of applying RPDTs in cervical surgeries. Studies that tested the accuracy and reliability of RPDTs in guiding cervical screw placements were included in this review. The fabrication workflow and usage of RPDTs, the accuracy and reliability of using RPDTs for screw and plate placement, the advantages and disadvantages of RPDTs and their prospects for future applications as a part of cervical fixation instrumentation are discussed. As the design of RPDTs becomes more rational, the accuracy and reliability of these devices have significantly improved in cervical fixation surgeries. Moreover, RPDTs decrease the intraoperative radiation exposure for surgeons and patients relative to conventional methods. However, some disadvantages also exist. The fabrication of RPDTs is time-consuming, and the time required to learn the related software is long. We believe that because of their merits, the RPDT technique is worth promoting for use in cervical surgeries. However, the time-consuming fabrication workflow and the long period required to learn the related software might limit its widespread use. In the future, the workflow should be simplified to reduce the extra workload for surgeons. Moreover, more clinical studies with high-level evidence are still needed to further test its accuracy and feasibility.

  5. Rapid world modelling for robotics

    SciTech Connect

    Littile, C.Q.; Wilson, C.W.

    1996-04-01

    The ability to use an interactive world model, whether it is for robotics simulation or most other virtual graphical environments, relies on the users ability to create an accurate world model. Typically this is a tedious process, requiring many hours to create 3-D CAD models of the surfaces within a workspace. The goal of this ongoing project is to develop usable methods to rapidly build world models of real world workspaces. This brings structure to an unstructured environment and allows graphical based robotics control to be accomplished in a reasonable time frame when traditional CAD modelling is not enough. To accomplish this, 3D range sensors are deployed to capture surface data within the workspace. This data is then transformed into surface maps, or models. A 3D world model of the workspace is built quickly and accurately, without ever having to put people in the environment.

  6. Using the prototype willingness model to predict doping in sport.

    PubMed

    Whitaker, L; Long, J; Petróczi, A; Backhouse, S H

    2014-10-01

    To enable preventive measures to be designed, it is important to identify modifiable distal and proximal factors underlying doping behavior. This study investigated aspects of the prototype willingness model in relation to doping. A cross-sectional study was conducted involving 729 competitive athletes. Following ethical approval, athletes (mean age = 28.8 ± 10.1 years; 63% male) completed an online questionnaire, which assessed doping-related attitudes, norms, prototype perceptions, outcome expectancies, and behavioral willingness. Using hierarchical multiple regression analysis, 54.4% of the total variance in willingness to dope was explained. Specifically, past doping, attitudes, and favorability of performance enhancing substance user prototypes were the strongest unique predictors of willingness to dope. Athletes appeared most willing to dope if they were to suffer an injury, a dip in performance, or think others are doping and getting away with it. National-level athletes displayed significantly greater willingness to dope (Kruskal-Wallis γ2 = 35.9, P < 0.001) and perceived themselves as significantly more similar to a doper (Kruskal-Wallis γ2 = 13.4, P = 0.004) than athletes competing at any other level. The findings highlight the importance of extending anti-doping provision beyond elite-level sport and the need to target athletes' doping-related perceptions.

  7. Rapid Target Modeling Through Genetic Inheritance Mechanism Genetically Evolved Target Prototypmg (GETP). Phase I

    DTIC Science & Technology

    1996-12-10

    Phase I Final Report Rapid Target Modeling Through Genetic Inheritance Mechanism Genetically Evolved Target Prototyping (GETP) Pbiai Dat December 10...COVERED 12/10/96 Final Report 5/7/96-12/10/96 A. TITE AND SUBTITU S. FUNDING NUMBERS Rapid Target Modeling Through Genetic Inheritance Mechanism... Genetically Evolved Target Prototyping (GETP) 6. AUTHOR(S) Dr. Jerzy Bala (P1) Dr. Peter Pachowicz (Co-P1) B.K. Gogia (PM) 7. PERFORMING ORGANIZATION

  8. Key elements to successful rapid prototyping and building of a Michelson interferometer for space-based sensing applications

    NASA Astrophysics Data System (ADS)

    Webb, Merritt; Cordray, David; Cronin, Shaun; Walker, Gary

    2004-02-01

    The Crosstrack Infrared Sounder (CrIS) is one of the sensors now under development for the National Polar-orbiting Operational Environmental Satellite System (NPOESS) program. In order to reduce program risk and verify instrument performance rapid prototyping of the sensor and critical subsystems has been utilized. Key among these was a prototype instrument and a prototype interferometer. This prototype instrument is referred to as the EDU1 (Engineering Development Unit). A second effort was the build of a prototype interferometer as a part of an internal ITT effort. This was an uncompensated version of the CrIS interferometer. This was referred to as the Aluminum Prototype Interferometer. The idea was to move rapidly to hardware while exploring new technologies. This was built in 4 months. There were key success factors for both efforts. A set of clear cardinal requirements was established. The layout and the cardinal requirements therefore provided a conceptual overview and a basis for deriving lower level requirements. These requirements remained basically unchanged throughout the effort. Vendors were closely worked with but; key to this was the GD&T dimensions and datum"s that were established. These enabled sub systems to be independently produced and "snapped together" to produce a final assembly in a minimum time. Essentially many of the critical optical alignments were built in to the individual parts so the subsequent shiming was not required. Electronics to control the porchswing and Dynamic Alignment Mechanism were developed in existing servo control test beds and designed to be FPGA based. This allowed a high degree of flexibility. Success was also based on continuity of the key engineering leadership and effective communications between the team and a clear understanding of the technical issues by the engineering leadership team.

  9. Rapid world modelling from a mobile platform

    SciTech Connect

    Barry, R.E.; Jones, J.P.; Little, C.Q.; Wilson, C.W.

    1997-04-01

    The ability to successfully use and interact with a computerized world model is dependent on the ability to create an accurate world model. The goal of this project was to develop a prototype system to remotely deploy sensors into a workspace, collect surface information, and rapidly build an accurate world model of that workspace. A key consideration was that the workspace areas are typically hazardous environments, where it is difficult or impossible for humans to enter. Therefore, the system needed to be fully remote, with no external connections. To accomplish this goal, an electric, mobile platform with battery power sufficient for both the platform and sensor electronics was procured and 3D range sensors were deployed on the platform to capture surface data within the workspace. A radio Ethernet connection was used to provide communications to the vehicle and all on-board electronics. Video from on-board cameras was also transmitted to the base station and used to teleoperate the vehicle. Range data generated by the on-board 3D sensors was transformed into surface maps, or models. Registering the sensor location to a consistent reference frame as the platform moved through the workspace allowed construction of a detailed 3D world model of the extended workspace.

  10. The Effect of Jetting Parameters on the Performance of Droplet Formation for Ink-Jet Rapid Prototyping

    NASA Technical Reports Server (NTRS)

    Helmer, Wayne

    1998-01-01

    Heinzl et al. (1985) reports that experiments in ink-jets to produce drawings or signals occurred as early as 1930. Various companies such as IBM and Pitney-Bowes have conducted extensive studies on these devices for many years. Many such reports are available in such journals as the IBM Journal of Research and Development. While numerous articles have been published on the jetting characteristics of ink and water, the literature is rather limited on fluids such as waxes (Gao & Sonin 1994) or non-water based fluids (Passow, et al. 1993). This present study extends the knowledge base to determine the performance of molten waxes in "ink-jet" type printers for rapid prototyping. The purpose of this research was to qualitatively and quantitatively study the droplet formation of a drop-on-demand ink-jet type nozzle system for rapid prototyping.

  11. The use of an automated flight test management system in the development of a rapid-prototyping flight research facility

    NASA Technical Reports Server (NTRS)

    Duke, Eugene L.; Hewett, Marle D.; Brumbaugh, Randal W.; Tartt, David M.; Antoniewicz, Robert F.; Agarwal, Arvind K.

    1988-01-01

    An automated flight test management system (ATMS) and its use to develop a rapid-prototyping flight research facility for artificial intelligence (AI) based flight systems concepts are described. The ATMS provides a flight test engineer with a set of tools that assist in flight planning and simulation. This system will be capable of controlling an aircraft during the flight test by performing closed-loop guidance functions, range management, and maneuver-quality monitoring. The rapid-prototyping flight research facility is being developed at the Dryden Flight Research Facility of the NASA Ames Research Center (Ames-Dryden) to provide early flight assessment of emerging AI technology. The facility is being developed as one element of the aircraft automation program which focuses on the qualification and validation of embedded real-time AI-based systems.

  12. Utility and Scope of Rapid Prototyping in Patients with Complex Muscular Ventricular Septal Defects or Double-Outlet Right Ventricle: Does it Alter Management Decisions?

    PubMed

    Bhatla, Puneet; Tretter, Justin T; Ludomirsky, Achi; Argilla, Michael; Latson, Larry A; Chakravarti, Sujata; Barker, Piers C; Yoo, Shi-Joon; McElhinney, Doff B; Wake, Nicole; Mosca, Ralph S

    2017-01-01

    Rapid prototyping facilitates comprehension of complex cardiac anatomy. However, determining when this additional information proves instrumental in patient management remains a challenge. We describe our experience with patient-specific anatomic models created using rapid prototyping from various imaging modalities, suggesting their utility in surgical and interventional planning in congenital heart disease (CHD). Virtual and physical 3-dimensional (3D) models were generated from CT or MRI data, using commercially available software for patients with complex muscular ventricular septal defects (CMVSD) and double-outlet right ventricle (DORV). Six patients with complex anatomy and uncertainty of the optimal management strategy were included in this study. The models were subsequently used to guide management decisions, and the outcomes reviewed. 3D models clearly demonstrated the complex intra-cardiac anatomy in all six patients and were utilized to guide management decisions. In the three patients with CMVSD, one underwent successful endovascular device closure following a prior failed attempt at transcatheter closure, and the other two underwent successful primary surgical closure with the aid of 3D models. In all three cases of DORV, the models provided better anatomic delineation and additional information that altered or confirmed the surgical plan. Patient-specific 3D heart models show promise in accurately defining intra-cardiac anatomy in CHD, specifically CMVSD and DORV. We believe these models improve understanding of the complex anatomical spatial relationships in these defects and provide additional insight for pre/intra-interventional management and surgical planning.

  13. Field flatteners fabricated with a rapid prototyper for K-edge subtraction imaging of small animals

    NASA Astrophysics Data System (ADS)

    Zhu, Ying; Zhang, Honglin; Bewer, Brian; Florin Gh. Popescu, Bogdan; Nichol, Helen; Chapman, Dean

    2008-04-01

    One of the difficulties in X-ray imaging is the need to record a wide dynamic range of intensities on the detector. For example, some rays may miss the object being imaged entirely while others may suffer many orders of magnitude attenuation in passing through. In K-edge subtraction (KES) [E. Rubenstein, et al., Trans. Am. Clin. Climatol. Assoc. 97 (1985) 27.] imaging subtle differences in transmission through an object about the absorption edge of an element are used to create an image of the projected density of that element. This is done by a logarithmic subtraction of images acquired with energies above and below the absorption edge. For KES, the detector must register this transmitted intensity range in a linear manner for the subtraction method to be successful. The range of intensities which may strike the detector has inspired the concept of a field flattener. A field flattener is a device placed in the beam path that attenuates the input monochromatic beam to equalize X-ray absorption due to differences in the density of soft and hard tissues of an object before it passes through the object and thus achieves a flattened image. This removes the need for a wide dynamic range linear detector and allows detectors with modest performance to be used successfully in KES applications. The field flattener improves the S/ N ratio since X-ray exposures can be increased up to detector saturation. However, a field flattener removes anatomical information from each raw image (above or below K-edge) that may provide useful landmarks. Using rapid prototyping technology, two sets of field flatteners were fabricated and used in a KES experiment. This paper describes the procedure to design and fabricate field flatteners based on animal images from X-ray computed tomography (CT). Analysis of experimental data and KES images of a rat head with and without the field flattener are also presented. The results show a promising improvement of S/ N ratio using a field flattener

  14. Marginal and internal fit of metal copings fabricated with rapid prototyping and conventional waxing.

    PubMed

    Farjood, Ehsan; Vojdani, Mahroo; Torabi, Kiyanoosh; Khaledi, Amir Ali Reza

    2017-01-01

    Given the limitations of conventional waxing, computer-aided design and computer-aided manufacturing (CAD-CAM) technologies have been developed as alternative methods of making patterns. The purpose of this in vitro study was to compare the marginal and internal fit of metal copings derived from wax patterns fabricated by rapid prototyping (RP) to those created by the conventional handmade technique. Twenty-four standardized brass dies were milled and divided into 2 groups (n=12) according to the wax pattern fabrication method. The CAD-RP group was assigned to the experimental group, and the conventional group to the control group. The cross-sectional technique was used to assess the marginal and internal discrepancies at 15 points on the master die by using a digital microscope. An independent t test was used for statistical analysis (α=.01). The CAD-RP group had a total mean (±SD) for absolute marginal discrepancy of 117.1 (±11.5) μm and a mean marginal discrepancy of 89.8 (±8.3) μm. The conventional group had an absolute marginal discrepancy 88.1 (±10.7) μm and a mean marginal discrepancy of 69.5 (±15.6) μm. The overall mean (±SD) of the total internal discrepancy, separately calculated as the axial internal discrepancy and occlusal internal discrepancy, was 95.9 (±8.0) μm for the CAD-RP group and 76.9 (±10.2) μm for the conventional group. The independent t test results showed significant differences between the 2 groups. The CAD-RP group had larger discrepancies at all measured areas than the conventional group, which was statistically significant (P<.01). Within the limitations of this in vitro study, the conventional method of wax pattern fabrication produced copings with better marginal and internal fit than the CAD-RP method. However, the marginal and internal fit for both groups were within clinically acceptable ranges. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights

  15. Rapid prototyping and the ASME B5.54 standard for evaluation of machine tool performance

    SciTech Connect

    Lewis, G.K.; Rhorer, D.

    1998-03-01

    The Directed Light Fabrication (DLF) process has shown feasibility for rapid fabrication of metal to full density. Structural properties equivalent to those of conventionally processed material have been achieved. The process is performed without the use of stereolithography files using a more conventional CNC approach to developing the motion path from the CAD solid model and using multi-axis positioning to deposit material in any plane, not just the horizontal plane used in many current processes. The important criteria for evaluating a solid free-form deposit were suggested and used to evaluate a part produced by DLF example presented here.

  16. Development of Rapid, Continuous Calibration Techniques and Implementation as a Prototype System for Civil Engineering Materials Evaluation

    NASA Astrophysics Data System (ADS)

    Scott, M. L.; Gagarin, N.; Mekemson, J. R.; Chintakunta, S. R.

    2011-06-01

    Until recently, civil engineering material calibration data could only be obtained from material sample cores or via time consuming, stationary calibration measurements in a limited number of locations. Calibration data are used to determine material propagation velocities of electromagnetic waves in test materials for use in layer thickness measurements and subsurface imaging. Limitations these calibration methods impose have been a significant impediment to broader use of nondestructive evaluation methods such as ground-penetrating radar (GPR). In 2006, a new rapid, continuous calibration approach was designed using simulation software to address these measurement limitations during a Federal Highway Administration (FHWA) research and development effort. This continuous calibration method combines a digitally-synthesized step-frequency (SF)-GPR array and a data collection protocol sequence for the common midpoint (CMP) method. Modeling and laboratory test results for various data collection protocols and materials are presented in this paper. The continuous-CMP concept was finally implemented for FHWA in a prototype demonstration system called the Advanced Pavement Evaluation (APE) system in 2009. Data from the continuous-CMP protocol is processed using a semblance/coherency analysis to determine material propagation velocities. Continuously calibrated pavement thicknesses measured with the APE system in 2009 are presented. This method is efficient, accurate, and cost-effective.

  17. Development of rapid, continuous calibration techniques and implementation as a prototype system for civil engineering materials evaluation

    SciTech Connect

    Scott, M. L.; Gagarin, N.; Mekemson, J. R.; Chintakunta, S. R.

    2011-06-23

    Until recently, civil engineering material calibration data could only be obtained from material sample cores or via time consuming, stationary calibration measurements in a limited number of locations. Calibration data are used to determine material propagation velocities of electromagnetic waves in test materials for use in layer thickness measurements and subsurface imaging. Limitations these calibration methods impose have been a significant impediment to broader use of nondestructive evaluation methods such as ground-penetrating radar (GPR). In 2006, a new rapid, continuous calibration approach was designed using simulation software to address these measurement limitations during a Federal Highway Administration (FHWA) research and development effort. This continuous calibration method combines a digitally-synthesized step-frequency (SF)-GPR array and a data collection protocol sequence for the common midpoint (CMP) method. Modeling and laboratory test results for various data collection protocols and materials are presented in this paper. The continuous-CMP concept was finally implemented for FHWA in a prototype demonstration system called the Advanced Pavement Evaluation (APE) system in 2009. Data from the continuous-CMP protocol is processed using a semblance/coherency analysis to determine material propagation velocities. Continuously calibrated pavement thicknesses measured with the APE system in 2009 are presented. This method is efficient, accurate, and cost-effective.

  18. Comparison of Conventional Methods and Laser-Assisted Rapid Prototyping for Manufacturing Fixed Dental Prostheses: An In Vitro Study.

    PubMed

    Pompa, Giorgio; Di Carlo, Stefano; De Angelis, Francesca; Cristalli, Maria Paola; Annibali, Susanna

    2015-01-01

    This study assessed whether there are differences in marginal fit between laser-fusion and conventional techniques to produce fixed dental prostheses (FDPs). A master steel die with 2 abutments was produced to receive a posterior 4-unit FDPs and single copings. These experimental models were divided into three groups (n = 20/group) manufactured: group 1, Ni-Cr alloy, with a lost-wax casting technique; group 2, Co-Cr alloy, with selective laser melting (SLM); and group 3, yttria-tetragonal zirconia polycrystal (Y-TZP), with a milling system. All specimens were cut along the longitudinal axis and their adaptation was measured at the marginal and shoulder areas on the right and left sides of each abutment. Measurements were made using a stereomicroscope (×60 magnification) and a scanning electron microscope (×800 magnification). The data were analyzed using one-way analysis of variance and the Bonferroni post hoc test, with a significance cutoff of 5%. Significant differences (P < 0.05) were observed between group 3 and the other groups. The marginal opening was smallest with Co-Cr alloy substructures, while the shoulder opening was smallest with Ni-Cr alloy substructures. Within the limitations of this study, the marginal fit of an FDP is better with rapid prototyping (RP) via SLM than conventional manufacturing systems.

  19. Comparison of Conventional Methods and Laser-Assisted Rapid Prototyping for Manufacturing Fixed Dental Prostheses: An In Vitro Study

    PubMed Central

    Pompa, Giorgio; Di Carlo, Stefano; De Angelis, Francesca; Cristalli, Maria Paola; Annibali, Susanna

    2015-01-01

    This study assessed whether there are differences in marginal fit between laser-fusion and conventional techniques to produce fixed dental prostheses (FDPs). A master steel die with 2 abutments was produced to receive a posterior 4-unit FDPs and single copings. These experimental models were divided into three groups (n = 20/group) manufactured: group 1, Ni-Cr alloy, with a lost-wax casting technique; group 2, Co-Cr alloy, with selective laser melting (SLM); and group 3, yttria-tetragonal zirconia polycrystal (Y-TZP), with a milling system. All specimens were cut along the longitudinal axis and their adaptation was measured at the marginal and shoulder areas on the right and left sides of each abutment. Measurements were made using a stereomicroscope (×60 magnification) and a scanning electron microscope (×800 magnification). The data were analyzed using one-way analysis of variance and the Bonferroni post hoc test, with a significance cutoff of 5%. Significant differences (P < 0.05) were observed between group 3 and the other groups. The marginal opening was smallest with Co-Cr alloy substructures, while the shoulder opening was smallest with Ni-Cr alloy substructures. Within the limitations of this study, the marginal fit of an FDP is better with rapid prototyping (RP) via SLM than conventional manufacturing systems. PMID:26576419

  20. Using INGRES as a rapid prototyping device during development of management information applications

    SciTech Connect

    Brice, L.; Connell, J.; Shafer, D.

    1983-01-01

    This paper presents case studies from the Administrative Data Processing Division of the Los Alamos National Laboratory where a prototyping too, the INGRES relational database system, has been used to develop management information systems. The tool has proved valuable in satisfying user requirements and expectations, and in aiding data processing in the analysis and specification phases of the system life cycle. The prototype approach helps enormously in bridging the developer-user communication gap and has been found to add a negligible amount of cost to the entire software development project. Presented here are four case studies of how INGRES has been employed in prototyping. Also presented are examples of specific INGRES features and how they were used in one of the case studies and further examples involving another similar case. Special considerations and cautions are required when using INGRES for prototyping, but the overall conclusion is that it is a tool which has tremendously benefited our organization. Whether the final implemented system is INGRES-based or not, prototyping greatly enhances the possibility of complete, correct and unambiguous specifications prior to final software product development.

  1. Rapid Prototyping: A Survey and Evaluation of Methodologies and Models

    DTIC Science & Technology

    1990-03-01

    Engineering, Cambridge, MA, pp. 179-180, May 1987. Prieto -Diaz, R. and Freeman, P., "Classifying Software For Reusability", IEEE Soft- ware, vol. 4, no. 1...Champaign, IL 61801 Dr. Alan Hevner University of Maryland College of Business Management Tydings Hall, Room 0137 College Park, MD 20742 Dr. Y. H. Chu

  2. Factors Influencing Rapid Prototyping Innovation Implementation: A Descriptive Model

    DTIC Science & Technology

    1990-03-01

    requirements of time, cost, need, and degree of technical risk . The acquisition process, though conceptually simple, is detailed in its...strategy. NDI can be considered as a balance of risk and technological advancement allowing the services to have a system in the field into the...traditional acquisition cycle, the savings in funding are immediately obvious. There are, however, certain risks involved when the decision is made to

  3. Optical choppers with rotational elements: modeling, design and prototypes

    NASA Astrophysics Data System (ADS)

    Duma, Virgil-Florin; Cira, Octavian; Demian, Dorin

    2017-05-01

    We present a brief overview of our contributions regarding the analysis and design of optical choppers. Their applications range numerous domains, from optical sensing in radiometry or telescopes to laser manufacturing and biomedical imaging - for example for the controlled attenuation of light, the elimination of selected spectral domains, or the switching of optical paths. While these aspects are pointed out, the paper describes our analysis, modeling, and manufacturing of prototypes for choppers with: (a) wheels with windows with linear margins; (b) wheels with windows with non-linear margins (semi-circular or elliptical), outward or inward; (c) rotational shafts with different shapes, with slits or with holes. While variant (a) represents classical choppers, variant (b) represents the "eclipse" choppers that we have developed and also patented for the solution with two adjustable wheels that can produce circular windows. Variant (c), of choppers with shafts is also a patent application. Their transmission functions are discussed, for the shape of the laser pulses produced and for the attenuation coefficients obtained. While this discussion has been completed analytically for top-hat laser beams, it has been modeled using simulations for Gaussian and Bessel beams. Design, manufacturing aspects, and prototypes of the different chopper configurations complete the presentation.

  4. An Embedded Systems Laboratory to Support Rapid Prototyping of Robotics and the Internet of Things

    ERIC Educational Resources Information Center

    Hamblen, J. O.; van Bekkum, G. M. E.

    2013-01-01

    This paper describes a new approach for a course and laboratory designed to allow students to develop low-cost prototypes of robotic and other embedded devices that feature Internet connectivity, I/O, networking, a real-time operating system (RTOS), and object-oriented C/C++. The application programming interface (API) libraries provided permit…

  5. An Embedded Systems Laboratory to Support Rapid Prototyping of Robotics and the Internet of Things

    ERIC Educational Resources Information Center

    Hamblen, J. O.; van Bekkum, G. M. E.

    2013-01-01

    This paper describes a new approach for a course and laboratory designed to allow students to develop low-cost prototypes of robotic and other embedded devices that feature Internet connectivity, I/O, networking, a real-time operating system (RTOS), and object-oriented C/C++. The application programming interface (API) libraries provided permit…

  6. Fused Deposition Modelling as Rapid Prototyping for Structural Material Improvement: Analytical Solution / Ātrās Prototipēšanas Ar Kausēšanas Metodi Strukturālā Uzlabojuma Analītisks Risinājums

    NASA Astrophysics Data System (ADS)

    Brensons, I.; Polukoshko, S.

    2013-10-01

    Fused deposition modelling (FDM) is one of the most effective rapid prototyping (RP) techniques due to its low cost, available materials and versatility. In FDM, a part of material (usually plastic) is made by heating this material to the molten state, and from the melt it is extruded through a nozzle and deposited on a surface. In the article, an alternative RP method is considered for improvement of the mechanical properties of a rapid prototype. The authors propose an analytical solution which allows for achievement of this purpose via advanced technologies. The base materials applied in RP technology can be combined with liquid resin which solidifies after a definite time. This makes it possible to create a channel through the prototype and fill it with another material having better mechanical properties. The optimal channel sizes can be chosen in order to raise the strength of material parts. Darbā tiek apskatīts ātrās prototipēšanas veids, kura pamatā ir detaļas veidošana, izmantojot kausētu materiālu parasti plastmasu. Šī detaļu veidošanas metode ir kļuvusi par vienu no visizplatītākajām tās zemo izmaksu, pieejamo materiālu un daudzpusības dēļ. Šī raksta mērķis ir izpētīt alternatīvu veidu, kā uzlabot prototipu mehāniskās īpašības, tādējādi palielinot printētu detaļu izmantošanu kā gala produktu. Raksts piedāvā analītisku risinājumu, kā uzlabot ātro prototipu mehāniskās īpašības, uzlabojot tehnoloģiskos procesus, kas iesaistīti detaļu izgatavošanā. Darba pamatā tiek izmantota 3D printēšanas tehnoloģijas iespēja veidot iekšējus kanālus bez ģeometriskiem ierobežojumiem, kā rezultātā ir iespējams izveidot iekšēju kanālu shēmu, ko pēc tam piepilda ar citu materiālu, kam ir labākas mehāniskās īpašības kā pamata materiālam. Pildīšanai izmantotais materiāls ir epoksīda sveķi, kas pieļauj vieglu iepildīšanu šķidrā fāzē, un sniedz labas mehāniskās īpašības p

  7. Rapid Prototyping for In Vitro Knee Rig Investigations of Prosthetized Knee Biomechanics: Comparison with Cobalt-Chromium Alloy Implant Material

    PubMed Central

    Schröder, Christian; Steinbrück, Arnd; Müller, Tatjana; Woiczinski, Matthias; Chevalier, Yan; Müller, Peter E.; Jansson, Volkmar

    2015-01-01

    Retropatellar complications after total knee arthroplasty (TKA) such as anterior knee pain and subluxations might be related to altered patellofemoral biomechanics, in particular to trochlear design and femorotibial joint positioning. A method was developed to test femorotibial and patellofemoral joint modifications separately with 3D-rapid prototyped components for in vitro tests, but material differences may further influence results. This pilot study aims at validating the use of prostheses made of photopolymerized rapid prototype material (RPM) by measuring the sliding friction with a ring-on-disc setup as well as knee kinematics and retropatellar pressure on a knee rig. Cobalt-chromium alloy (standard prosthesis material, SPM) prostheses served as validation standard. Friction coefficients between these materials and polytetrafluoroethylene (PTFE) were additionally tested as this latter material is commonly used to protect pressure sensors in experiments. No statistical differences were found between friction coefficients of both materials to PTFE. UHMWPE shows higher friction coefficient at low axial loads for RPM, a difference that disappears at higher load. No measurable statistical differences were found in knee kinematics and retropatellar pressure distribution. This suggests that using polymer prototypes may be a valid alternative to original components for in vitro TKA studies and future investigations on knee biomechanics. PMID:25879019

  8. Rapid prototyping for in vitro knee rig investigations of prosthetized knee biomechanics: comparison with cobalt-chromium alloy implant material.

    PubMed

    Schröder, Christian; Steinbrück, Arnd; Müller, Tatjana; Woiczinski, Matthias; Chevalier, Yan; Weber, Patrick; Müller, Peter E; Jansson, Volkmar

    2015-01-01

    Retropatellar complications after total knee arthroplasty (TKA) such as anterior knee pain and subluxations might be related to altered patellofemoral biomechanics, in particular to trochlear design and femorotibial joint positioning. A method was developed to test femorotibial and patellofemoral joint modifications separately with 3D-rapid prototyped components for in vitro tests, but material differences may further influence results. This pilot study aims at validating the use of prostheses made of photopolymerized rapid prototype material (RPM) by measuring the sliding friction with a ring-on-disc setup as well as knee kinematics and retropatellar pressure on a knee rig. Cobalt-chromium alloy (standard prosthesis material, SPM) prostheses served as validation standard. Friction coefficients between these materials and polytetrafluoroethylene (PTFE) were additionally tested as this latter material is commonly used to protect pressure sensors in experiments. No statistical differences were found between friction coefficients of both materials to PTFE. UHMWPE shows higher friction coefficient at low axial loads for RPM, a difference that disappears at higher load. No measurable statistical differences were found in knee kinematics and retropatellar pressure distribution. This suggests that using polymer prototypes may be a valid alternative to original components for in vitro TKA studies and future investigations on knee biomechanics.

  9. A prototype software methodology for the rapid evaluation of biomanufacturing process options.

    PubMed

    Chhatre, Sunil; Francis, Richard; O'Donovan, Kieran; Titchener-Hooker, Nigel J; Newcombe, Anthony R; Keshavarz-Moore, Eli

    2007-10-01

    A three-layered simulation methodology is described that rapidly evaluates biomanufacturing process options. In each layer, inferior options are screened out, while more promising candidates are evaluated further in the subsequent, more refined layer, which uses more rigorous models that require more data from time-consuming experimentation. Screening ensures laboratory studies are focused only on options showing the greatest potential. To simplify the screening, outputs of production level, cost and time are combined into a single value using multi-attribute-decision-making techniques. The methodology was illustrated by evaluating alternatives to an FDA (U.S. Food and Drug Administration)-approved process manufacturing rattlesnake antivenom. Currently, antivenom antibodies are recovered from ovine serum by precipitation/centrifugation and proteolyzed before chromatographic purification. Alternatives included increasing the feed volume, replacing centrifugation with microfiltration and replacing precipitation/centrifugation with a Protein G column. The best alternative used a higher feed volume and a Protein G step. By rapidly evaluating the attractiveness of options, the methodology facilitates efficient and cost-effective process development.

  10. Rapid Prototyping of Slot Die Devices for Roll to Roll Production of EL Fibers

    PubMed Central

    Bellingham, Alyssa; Bromhead, Nicholas; Fontecchio, Adam

    2017-01-01

    There is a growing interest in fibers supporting optoelectrical properties for textile and wearable display applications. Solution-processed electroluminescent (EL) material systems can be continuously deposited onto fiber or yarn substrates in a roll-to-roll process, making it easy to scale manufacturing. It is important to have precise control over layer deposition to achieve uniform and reliable light emission from these EL fibers. Slot-die coating offers this control and increases the rate of EL fiber production. Here, we report a highly adaptable, cost-effective 3D printing model for developing slot dies used in automatic coating systems. The resulting slot-die coating system enables rapid, reliable production of alternating current powder-based EL (ACPEL) fibers and can be adapted for many material systems. The benefits of this system over dip-coating for roll-to-roll production of EL fibers are demonstrated in this work. PMID:28772954

  11. Rapid Prototyping of Slot Die Devices for Roll to Roll Production of EL Fibers.

    PubMed

    Bellingham, Alyssa; Bromhead, Nicholas; Fontecchio, Adam

    2017-05-29

    There is a growing interest in fibers supporting optoelectrical properties for textile and wearable display applications. Solution-processed electroluminescent (EL) material systems can be continuously deposited onto fiber or yarn substrates in a roll-to-roll process, making it easy to scale manufacturing. It is important to have precise control over layer deposition to achieve uniform and reliable light emission from these EL fibers. Slot-die coating offers this control and increases the rate of EL fiber production. Here, we report a highly adaptable, cost-effective 3D printing model for developing slot dies used in automatic coating systems. The resulting slot-die coating system enables rapid, reliable production of alternating current powder-based EL (ACPEL) fibers and can be adapted for many material systems. The benefits of this system over dip-coating for roll-to-roll production of EL fibers are demonstrated in this work.

  12. Advanced product realization through model-based design and virtual prototyping

    SciTech Connect

    Andreas, R.D.

    1995-03-01

    Several government agencies and industrial sectors have recognized the need for, and payoff of, investing in the methodologies and associated technologies for improving the product realization process. Within the defense community as well as commercial industry, there are three major needs. First, they must reduce the cost of military products, of related manufacturing processes, and of the enterprises that have to be maintained. Second, they must reduce the time required to realize products while still applying the latest technologies. Finally, they must improve the predictability of process attributes, product performance, cost, schedule and quality. They must continue to advance technology, quickly incorporate their innovations in new products and in processes to produce them, and they need to capitalize on the raw computational power and communications bandwidth that continues to become available at decreasing cost. Sandia National Laboratories initiative is pursuing several interrelated, key concepts and technologies in order to enable such product realization process improvements: model-based design; intelligent manufacturing processes; rapid virtual and physical prototyping; and agile people/enterprises. While progress in each of these areas is necessary, this paper only addresses a portion of the overall initiative. First a vision of a desired future capability in model-based design and virtual prototyping is presented. This is followed by a discussion of two specific activities parametric design analysis of Synthetic Aperture Radars (SARs) and virtual prototyping of miniaturized high-density electronics -- that exemplify the vision as well as provide a status report on relevant work in progress.

  13. Rehabilitation of the nose using CAD/CAM and rapid prototyping technology after ablative surgery of squamous cell carcinoma: a pilot clinical report.

    PubMed

    Ciocca, Leonardo; De Crescenzio, Francesca; Fantini, Massimiliano; Scotti, Roberto

    2010-01-01

    Restoration of a nasal defect after ablative surgery for squamous cell carcinoma necessitates replacing the missing volume and anchoring a prosthesis to the patient's face. This report describes the failure of plastic reconstructive surgery after ablation of a squamous cell cancer of the nose and the esthetic and functional restoration of the patient with a nasal prosthesis. The process of making an implant-supported prosthesis using digital technology, including digitized anatomic models from a "nose library," and the rapid prototyping of the mesiostructure for bar anchorage and of the mold for silicone processing are presented.

  14. [Computer-aided method and rapid prototyping for the personalized fabrication of a silicone bandage digital prosthesis].

    PubMed

    Ventura Ferreira, Nuno; Leal, Nuno; Correia Sá, Inês; Reis, Ana; Marques, Marisa

    2014-01-01

    The fabrication of digital prostheses has acquired growing importance not only for the possibility for the patient to overcome psychosocial trauma but also to promote grip functionality. An application method of three dimensional-computer-aided design technologies for the production of passive prostheses is presented by means of a fifth finger amputee clinical case following bilateral hand replantation.Three-dimensional-computerized tomography was used for the collection of anthropometric images of the hands. Computer-aided design techniques were used to develop the digital file-based prosthesis from the reconstruction images by inversion and superimposing the contra-lateral finger images. The rapid prototyping manufacturing method was used for the production of a silicone bandage prosthesis prototype. This approach replaces the traditional manual method by a virtual method that is basis for the optimization of a high speed, accurate and innovative process.

  15. Eagle II: A prototype for multi-resolution combat modeling

    SciTech Connect

    Powell, D.R.; Hutchinson, J.L.

    1993-02-01

    Eagle 11 is a prototype analytic model derived from the integration of the low resolution Eagle model with the high resolution SIMNET model. This integration promises a new capability to allow for a more effective examination of proposed or existing combat systems that could not be easily evaluated using either Eagle or SIMNET alone. In essence, Eagle II becomes a multi-resolution combat model in which simulated combat units can exhibit both high and low fidelity behavior at different times during model execution. This capability allows a unit to behave in a highly manner only when required, thereby reducing the overall computational and manpower requirements for a given study. In this framework, the SIMNET portion enables a highly credible assessment of the performance of individual combat systems under consideration, encompassing both engineering performance and crew capabilities. However, when the assessment being conducted goes beyond system performance and extends to questions of force structure balance and sustainment, then SISMNET results can be used to ``calibrate`` the Eagle attrition process appropriate to the study at hand. Advancing technologies, changes in the world-wide threat, requirements for flexible response, declining defense budgets, and down-sizing of military forces motivate the development of manpower-efficient, low-cost, responsive tools for combat development studies. Eagle and SIMNET both serve as credible and useful tools. The integration of these two models promises enhanced capabilities to examine the broader, deeper, more complex battlefield of the future with higher fidelity, greater responsiveness and low overall cost.

  16. Eagle II: A prototype for multi-resolution combat modeling

    SciTech Connect

    Powell, D.R.; Hutchinson, J.L.

    1993-01-01

    Eagle 11 is a prototype analytic model derived from the integration of the low resolution Eagle model with the high resolution SIMNET model. This integration promises a new capability to allow for a more effective examination of proposed or existing combat systems that could not be easily evaluated using either Eagle or SIMNET alone. In essence, Eagle II becomes a multi-resolution combat model in which simulated combat units can exhibit both high and low fidelity behavior at different times during model execution. This capability allows a unit to behave in a highly manner only when required, thereby reducing the overall computational and manpower requirements for a given study. In this framework, the SIMNET portion enables a highly credible assessment of the performance of individual combat systems under consideration, encompassing both engineering performance and crew capabilities. However, when the assessment being conducted goes beyond system performance and extends to questions of force structure balance and sustainment, then SISMNET results can be used to calibrate'' the Eagle attrition process appropriate to the study at hand. Advancing technologies, changes in the world-wide threat, requirements for flexible response, declining defense budgets, and down-sizing of military forces motivate the development of manpower-efficient, low-cost, responsive tools for combat development studies. Eagle and SIMNET both serve as credible and useful tools. The integration of these two models promises enhanced capabilities to examine the broader, deeper, more complex battlefield of the future with higher fidelity, greater responsiveness and low overall cost.

  17. A highly miniaturized electron and ion energy spectrometer prototype for the rapid analysis of space plasmas

    SciTech Connect

    Bedington, R.; Kataria, D. O.; Smith, A.

    2014-02-15

    MEMS (Micro Electro-Mechanical Systems) plasma analyzers are a promising possibility for future space missions but conventional instrument designs are not necessarily well suited to micro-fabrication. Here, a candidate design for a MEMS-based instrument has been prototyped using electron-discharge machining. The device features 10 electrostatic analyzers that, with a single voltage applied to it, allow five different energies of electron and five different energies of positive ion to be simultaneously sampled. It has been simulated using SIMION and the electron response characteristics tested in an instrument calibration chamber. Small deviations found in the electrode spacing of the as-built prototype were found to have some effect on the electron response characteristics but do not significantly impede its performance.

  18. Rapid Prototyping across the Spectrum: RF to Optical 3D Electromagnetic Structures

    DTIC Science & Technology

    2015-11-17

    abilities (e.g. nanoparticle loaded polymers that can be ink-jet deposited enable unique plasmonic fields in a device) [59]. Prototyping processes can be... nanoparticle arrays with high purity by utilizing precursors without carbon/phosphorus based architectures which mitigate undesirable impurities of...strength, heat resistance and biocompatibility are desired. Other combinations of polymer and nanoparticles such as silica can be used to form optically

  19. A rapid prototyping technique for valves and filters in centrifugal microfluidic devices.

    PubMed

    LaCroix-Fralish, Angela; Templeton, Erin J; Salin, Eric D; Skinner, Cameron D

    2009-11-07

    Using short lengths of fused silica capillary tubing embedded in the disk, a system for valving and filtering samples on centrifugal microfluidic devices has been designed and implemented. Sedimentation of turbid samples and transfer of the clear supernatant was also accomplished. Also demonstrated is the transfer of the liquid through a second capillary valve to the final reservoir. By controlling rotational speed, sedimentation and multiple step valving operations are readily implemented and easily prototyped.

  20. Development of the prototype Munitions Case Moisture Meter, Model ORNL-1

    SciTech Connect

    Agouridis, D.C.; Gayle, T.M.; Griest, W.H.

    1993-02-24

    There is a great need for a rapid and simple means of determining the moisture content in combustible cartridge case (ccc) munitions. Previous studies have demonstrated that accumulation of moisture in ccc rounds, such as the M829, leads to softening of the case wall and weakening of the adhesive joint. Moisture in the ccc can lead to incomplete combustion of the case upon firing the round. Currently, there are no facile methods for measuring the moisture content. A prototype portable meter for non-destructive and rapid estimation of moisture in ccc has been developed. The Munitions Case Moisture Meter Model ORNL-1 demonstrates the feasibility of developing an instrument based on the moisture dependence of dielectric properties, to measure moisture in ccc munitions in storage and in the field. These instruments are simple, inexpensive, lightweight, portable, low-power battery operated, and intrinsically safe. They provide nondestructive, noninvasive, and rapid measurements. Calibration data for the prototype are not available at this time. Therefore, calibration of the meter and the development of a scale reading directly moisture content in munitions rounds could not be completed. These data will be supplied by the US Army from its tests of the meter with actual munitions. However, experimental results on empty cccs in laboratory conditions demonstrate satisfactory performance of the instrument. Additional work is needed to bring the prototype to its optimum usefulness and accuracy for field measurements. This includes: Calibration of the meter scale with full-up munitions; Data and evaluation procedures to adjust the performance of the meter for different environmental conditions such as temperature and humidity; and Studies of the dielectric properties of moist ccc materials, as a function of frequency and temperature, are needed for adjustment of the meter for optimal performance.