Science.gov

Sample records for control systems based

  1. Space construction base control system

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Aspects of an attitude control system were studied and developed for a large space base that is structurally flexible and whose mass properties change rather dramatically during its orbital lifetime. Topics of discussion include the following: (1) space base orbital pointing and maneuvering; (2) angular momentum sizing of actuators; (3) momentum desaturation selection and sizing; (4) multilevel control technique applied to configuration one; (5) one-dimensional model simulation; (6) N-body discrete coordinate simulation; (7) structural analysis math model formulation; and (8) discussion of control problems and control methods.

  2. Space construction base control system

    NASA Technical Reports Server (NTRS)

    Kaczynski, R. F.

    1979-01-01

    Several approaches for an attitude control system are studied and developed for a large space construction base that is structurally flexible. Digital simulations were obtained using the following techniques: (1) the multivariable Nyquist array method combined with closed loop pole allocation, (2) the linear quadratic regulator method. Equations for the three-axis simulation using the multilevel control method were generated and are presented. Several alternate control approaches are also described. A technique is demonstrated for obtaining the dynamic structural properties of a vehicle which is constructed of two or more submodules of known dynamic characteristics.

  3. Adaptable state based control system

    NASA Technical Reports Server (NTRS)

    Rasmussen, Robert D. (Inventor); Dvorak, Daniel L. (Inventor); Gostelow, Kim P. (Inventor); Starbird, Thomas W. (Inventor); Gat, Erann (Inventor); Chien, Steve Ankuo (Inventor); Keller, Robert M. (Inventor)

    2004-01-01

    An autonomous controller, comprised of a state knowledge manager, a control executor, hardware proxies and a statistical estimator collaborates with a goal elaborator, with which it shares common models of the behavior of the system and the controller. The elaborator uses the common models to generate from temporally indeterminate sets of goals, executable goals to be executed by the controller. The controller may be updated to operate in a different system or environment than that for which it was originally designed by the replacement of shared statistical models and by the instantiation of a new set of state variable objects derived from a state variable class. The adaptation of the controller does not require substantial modification of the goal elaborator for its application to the new system or environment.

  4. FIPA agent based network distributed control system

    SciTech Connect

    D. Abbott; V. Gyurjyan; G. Heyes; E. Jastrzembski; C. Timmer; E. Wolin

    2003-03-01

    A control system with the capabilities to combine heterogeneous control systems or processes into a uniform homogeneous environment is discussed. This dynamically extensible system is an example of the software system at the agent level of abstraction. This level of abstraction considers agents as atomic entities that communicate to implement the functionality of the control system. Agents' engineering aspects are addressed by adopting the domain independent software standard, formulated by FIPA. Jade core Java classes are used as a FIPA specification implementation. A special, lightweight, XML RDFS based, control oriented, ontology markup language is developed to standardize the description of the arbitrary control system data processor. Control processes, described in this language, are integrated into the global system at runtime, without actual programming. Fault tolerance and recovery issues are also addressed.

  5. Development of Arduino based wireless control system

    NASA Astrophysics Data System (ADS)

    Sun, Zhuoxiong; Dyke, Shirley J.; Pena, Francisco; Wilbee, Alana

    2015-03-01

    Over the past few decades, considerable attention has been given to structural control systems to mitigate structural vibration under natural hazards such as earthquakes and extreme weather conditions. Traditional wired structural control systems often employ a large amount of cables for communication among sensors, controllers and actuators. In such systems, implementation of wired sensors is usually quite complicated and expensive, especially on large scale structures such as bridges and buildings. To reduce the laborious installation and maintenance cost, wireless control systems (WCSs) are considered as a novel approach for structural vibration control. In this work, a WCS is developed based on the open source Arduino platform. Low cost, low power wireless sensing and communication components are built on the Arduino platform. Structural control algorithms are embedded within the wireless sensor board for feedback control. The developed WCS is first validated through a series of tests. Next, numerical simulations are performed simulating wireless control of a 3-story shear structure equipped with a semi-active control device (MR damper). Finally, experimental studies are carried out implementing the WCS on the 3-story shear structure in the Intelligent Infrastructure Systems Lab (IISL). A hydraulic shake table is used to generate seismic ground motions. The control performance is evaluated with the impact of modeling uncertainties, measurement noises as well as time delay and data loss induced by the wireless network. The developed WCS is shown to be effective in controlling structural vibrations under several historical earthquake ground motions.

  6. Developing stereo image based robot control system

    SciTech Connect

    Suprijadi,; Pambudi, I. R.; Woran, M.; Naa, C. F; Srigutomo, W.

    2015-04-16

    Application of image processing is developed in various field and purposes. In the last decade, image based system increase rapidly with the increasing of hardware and microprocessor performance. Many fields of science and technology were used this methods especially in medicine and instrumentation. New technique on stereovision to give a 3-dimension image or movie is very interesting, but not many applications in control system. Stereo image has pixel disparity information that is not existed in single image. In this research, we proposed a new method in wheel robot control system using stereovision. The result shows robot automatically moves based on stereovision captures.

  7. An interferometer based phase control system

    NASA Technical Reports Server (NTRS)

    Ott, J. H.; Rice, J. S.

    1980-01-01

    An interferometer based phase control system for focusing and pointing the solar power satellite (SPS) power beam is discussed. The system is ground based and closed loop. One receiving antenna is required on Earth. A conventional uplink data channel transmits an 8 bit phase error correction back to the SPS for sequential calibration of each power module. Beam pointing resolution is better than 140 meters at the rectenna.

  8. Interferometer-based phase control system

    SciTech Connect

    Ott, J.H.; Rice, J.S.

    1980-01-01

    An interferometer-based phase control system for focusing and pointing the SPS power beam is discussed. The system is ground based and closed loop. One receiving antenna is required on earth. A conventional uplink data channel transmits an 8-bit phase error correction back to the SPS for sequential calibration of each power module. Beam pointing resolution is better than 140 meters at the Rectenna. 1 ref.

  9. FPGA based Smart Wireless MIMO Control System

    NASA Astrophysics Data System (ADS)

    Usman Ali, Syed M.; Hussain, Sajid; Akber Siddiqui, Ali; Arshad, Jawad Ali; Darakhshan, Anjum

    2013-12-01

    In our present work, we have successfully designed, and developed an FPGA based smart wireless MIMO (Multiple Input & Multiple Output) system capable of controlling multiple industrial process parameters such as temperature, pressure, stress and vibration etc. To achieve this task we have used Xilin x Spartan 3E FPGA (Field Programmable Gate Array) instead of conventional microcontrollers. By employing FPGA kit to PC via RF transceivers which has a working range of about 100 meters. The developed smart system is capable of performing the control task assigned to it successfully. We have also provided a provision to our proposed system that can be accessed for monitoring and control through the web and GSM as well. Our proposed system can be equally applied to all the hazardous and rugged industrial environments where a conventional system cannot work effectively.

  10. Transputer based control system for MTLRS

    NASA Technical Reports Server (NTRS)

    Vermaat, Erik; Offierski, Jacek W.; Otten, Klaus H.; Beek, Wiard; Vanes, C.; Sperber, Peter

    1993-01-01

    The Modular Transportable Laser Ranging Systems (MTLRS-1 and MTLRS-2) have been designed in the early eighties and have been in operation very successfully since 1984. The original design of the electronic control system was based on the philosophy of parallel processing, but these ideas could at that time only be implemented to a very limited extent. This present system utilizes two MOTOROLA 6800 8-bit processors slaved to a HP A-600 micro-computer. These processors support the telescope tracking system and the data-acquisition/formatting, respectively. Nevertheless, the overall design still is largely hardware oriented. Because the system is now some nine years old, aging of components increases the risk of malfunctioning and some components or units are outdated and not available anymore. The control system for MTLRS is now being re-designed completely, based on the original philosophy of parallel processing, making use of contemporary advanced electronics and processor technology. The new design aims at the requirements for Satellite Laser Ranging (SLR) in the nineties, making use of the extensive operational experience obtained with the two transportable systems.

  11. An interferometer-based phase control system

    NASA Technical Reports Server (NTRS)

    Ott, J. H.; Rice, J. S.

    1981-01-01

    A system for focusing and pointing the SPS power beam is discussed. The system is ground based and closed loop. One receiving antenna is required on earth. A conventional uplinked data channel transmits an 8-bit phase error correction back to the SPS for sequential calibration of each power module. Beam pointing resolution is better than 140 meters at the rectenna.

  12. An interferometer-based phase control system

    NASA Technical Reports Server (NTRS)

    Ott, J. H.; Rice, J. S.

    1980-01-01

    A system for focusing and pointing the SPS power beam is discussed. The system is ground based and closed loop. One receiving antenna is required on Earth. A conventional uplink data channel transmits an 8-bit phase error correlation back to the SPS for sequential calibration of each power module. Beam pointing resolution is better than 140 meters at the Rectenna.

  13. Experimental Physics and Industrial Control System BASE

    2002-08-01

    EPICS is a set of software tools and applications developed initially by the Los Alamos National Laboratories for the control of large accelerators, enhanced by contributions from users worldwide and continuing development for application to other large scientific experimental equipment, such as telescopes and detectors. EPICS consists of EPICS BASE, Extensions, and other unbundled modules. EPICS BASE marks a change in the handling of the distribution of the software starting with the EPICS BASE 3.13.7more » AND 3.140beta2 software.« less

  14. Model based controls and the AGS booster controls system architecture

    SciTech Connect

    Casella, R.A.

    1987-08-18

    The Heavy Ion Transfer Line used to inject heavy ions created at the Tandem Van de Graaff into the Alternating Gradient Synchrotron (AGS) is briefly discussed, particularly as regards its control system. (LEW)

  15. Observer-based controller for nonlinear analytical systems

    NASA Astrophysics Data System (ADS)

    Elloumi, S.; Belhouane, M. M.; Benhadj Braiek, N.

    2016-06-01

    In this paper, we propose to design a polynomial observer-based control for nonlinear systems and to determine sufficient linear matrix inequality (LMI) global stabilisation conditions of the polynomial controlled system augmented by its observer. The design of the observer-based control leverages some notations from the Kronecker product and the power of matrices properties for the state space description of polynomial systems. The stability study of the polynomial controlled system augmented by its observer is based on the Lyapunov stability direct method. Intensive simulations are performed to illustrate the validity and the effectiveness of the polynomial approach used to design the control.

  16. An expert system based intelligent control scheme for space bioreactors

    NASA Technical Reports Server (NTRS)

    San, Ka-Yiu

    1988-01-01

    An expert system based intelligent control scheme is being developed for the effective control and full automation of bioreactor systems in space. The scheme developed will have the capability to capture information from various resources including heuristic information from process researchers and operators. The knowledge base of the expert system should contain enough expertise to perform on-line system identification and thus be able to adapt the controllers accordingly with minimal human supervision.

  17. LMI-based controller design for dynamic variable structure systems

    NASA Astrophysics Data System (ADS)

    Ohtake, Hiroshi; Tanaka, Kazuo

    2005-12-01

    This paper presents controller design conditions for dynamic variable structure systems in terms of linear matrix inequalities (LMIs). In our previous paper, we proposed the dynamic variable structure system and derived its controller design conditions using switching fuzzy model-based control approach. However, the controller design conditions were given in terms of bilinear matrix inequalities (BMIs). In this paper, by introducing the augmented system which consists of the switching fuzzy model and a stable linear system, we derive new controller design conditions in terms of linear matrix inequalities (LMIs) for the dynamic variable structure systems. A simulation result shows the utility of this control approach.

  18. Design of energy-based terrain following flight control system

    NASA Astrophysics Data System (ADS)

    Wang, Wei; Li, Aijun; Xie, Yanwu; Tan, Jian

    2006-11-01

    Historically, aircraft longitudinal control has been realized by means of two loops: flight path (the control variable is elevator displacement) and speed control (the control variable is propulsive thrust or engine power). Both the elevator and throttle control cause coupled altitude and speed response, which exerts negative effects on longitudinal flight performance of aircraft, especially for Terrain Following(TF) flight. Energy-based method can resolve coupled problem between flight speed and path by controlling total energy rate and energy distribution rate between elevator and throttle. In this paper, energy-based control method is applied to design a TF flight control system for controlling flight altitude directly. An error control method of airspeed and altitude is adopted to eliminate the stable error of the total energy control system when decoupling control. Pitch loop and pitch rate feedback loop are designed for the system to damp the oscillatory response produced by TF system. The TF flight control system structure diagram and an aircraft point-mass energy motion model including basic control loops are given and used to simulate decoupling performance of the TF fight control system. Simulation results show that the energy-based TF flight control system can decouple flight velocity and flight path angle, exactly follow planned flight path, and greatly reduce altitude error, which is between +10m and -8m.

  19. Ethernet Based Embedded IOC for FEL Control Systems

    SciTech Connect

    Yan, Jianxun; Sexton, Daniel; Grippo, Albert; Moore, Steven; Jordan, Kevin

    2008-01-01

    An Ethernet based embedded Input Output Controller (IOC) has been developed as part of an upgrade to the control system for the Free Electron Laser Project at Jefferson Lab. Currently most of the FEL systems are controlled, configured and monitored using a central VME bus-based configuration. These crate based systems are limited in growth and usually interleave multiple systems. In order to accommodate incremental system growth and lower channel costs, we developed a stand-alone system, an Ethernet based embedded controller called the Single Board IOC (SBIOC). The SBIOC is a module which integrates an Altera FPGA and the Arcturus uCdimm Coldfire 5282 Microcontroller daughter card into one module, which can be easily configured for different kinds of I/O devices. The microcontroller is a complete System-on-Module, including three highly integrated functional blocks, the core processor, memory, and Ethernet communication. A real-time operating system, RTEMS is cross compiled with

  20. The Abstract Machine Model for Transaction-based System Control

    SciTech Connect

    Chassin, David P.

    2003-01-31

    Recent work applying statistical mechanics to economic modeling has demonstrated the effectiveness of using thermodynamic theory to address the complexities of large scale economic systems. Transaction-based control systems depend on the conjecture that when control of thermodynamic systems is based on price-mediated strategies (e.g., auctions, markets), the optimal allocation of resources in a market-based control system results in an emergent optimal control of the thermodynamic system. This paper proposes an abstract machine model as the necessary precursor for demonstrating this conjecture and establishes the dynamic laws as the basis for a special theory of emergence applied to the global behavior and control of complex adaptive systems. The abstract machine in a large system amounts to the analog of a particle in thermodynamic theory. The permit the establishment of a theory dynamic control of complex system behavior based on statistical mechanics. Thus we may be better able to engineer a few simple control laws for a very small number of devices types, which when deployed in very large numbers and operated as a system of many interacting markets yields the stable and optimal control of the thermodynamic system.

  1. Estimator Based Controller for High Speed Flywheel Magnetic Bearing System

    NASA Technical Reports Server (NTRS)

    Dever, Timothy P.; Brown, Gerald V.; Jansen, Ralph H.

    2002-01-01

    A flywheel system and its operator interface are described. Measurements of magnetic bearing negative stiffness are performed. Two digital magnetic bearing control algorithms (PD and estimator based) are defined and their implementations are described. Tuning of each controller is discussed. Comparison of the two controllers' stability, damping noise, and operating current are described. Results describing the superiority of the estimator-based controller are presented and discussed.

  2. Controlled cooling of an electronic system based on projected conditions

    SciTech Connect

    David, Milnes P.; Iyengar, Madhusudan K.; Schmidt, Roger R.

    2015-08-18

    Energy efficient control of a cooling system cooling an electronic system is provided based, in part, on projected conditions. The control includes automatically determining an adjusted control setting(s) for an adjustable cooling component(s) of the cooling system. The automatically determining is based, at least in part, on projected power consumed by the electronic system at a future time and projected temperature at the future time of a heat sink to which heat extracted is rejected. The automatically determining operates to reduce power consumption of the cooling system and/or the electronic system while ensuring that at least one targeted temperature associated with the cooling system or the electronic system is within a desired range. The automatically determining may be based, at least in part, on an experimentally obtained model(s) relating the targeted temperature and power consumption of the adjustable cooling component(s) of the cooling system.

  3. Controlled cooling of an electronic system based on projected conditions

    DOEpatents

    David, Milnes P.; Iyengar, Madhusudan K.; Schmidt, Roger R.

    2016-05-17

    Energy efficient control of a cooling system cooling an electronic system is provided based, in part, on projected conditions. The control includes automatically determining an adjusted control setting(s) for an adjustable cooling component(s) of the cooling system. The automatically determining is based, at least in part, on projected power consumed by the electronic system at a future time and projected temperature at the future time of a heat sink to which heat extracted is rejected. The automatically determining operates to reduce power consumption of the cooling system and/or the electronic system while ensuring that at least one targeted temperature associated with the cooling system or the electronic system is within a desired range. The automatically determining may be based, at least in part, on an experimentally obtained model(s) relating the targeted temperature and power consumption of the adjustable cooling component(s) of the cooling system.

  4. An adaptive P300-based control system

    NASA Astrophysics Data System (ADS)

    Jin, Jing; Allison, Brendan Z.; Sellers, Eric W.; Brunner, Clemens; Horki, Petar; Wang, Xingyu; Neuper, Christa

    2011-06-01

    An adaptive P300 brain-computer interface (BCI) using a 12 × 7 matrix explored new paradigms to improve bit rate and accuracy. During online use, the system adaptively selects the number of flashes to average. Five different flash patterns were tested. The 19-flash paradigm represents the typical row/column presentation (i.e. 12 columns and 7 rows). The 9- and 14-flash A and B paradigms present all items of the 12 × 7 matrix three times using either 9 or 14 flashes (instead of 19), decreasing the amount of time to present stimuli. Compared to 9-flash A, 9-flash B decreased the likelihood that neighboring items would flash when the target was not flashing, thereby reducing the interference from items adjacent to targets. 14-flash A also reduced the adjacent item interference and 14-flash B additionally eliminated successive (double) flashes of the same item. Results showed that the accuracy and bit rate of the adaptive system were higher than those of the non-adaptive system. In addition, 9- and 14-flash B produced significantly higher performance than their respective A conditions. The results also show the trend that the 14-flash B paradigm was better than the 19-flash pattern for naive users.

  5. Engine control system having speed-based timing

    DOEpatents

    Willi, Martin L.; Fiveland, Scott B.; Montgomery, David T.; Gong, Weidong

    2012-02-14

    A control system for an engine having a cylinder is disclosed having an engine valve movable to regulate a fluid flow of the cylinder and an actuator associated with the engine valve. The control system also has a controller in communication with the actuator. The controller is configured to receive a signal indicative of engine speed and compare the engine speed signal with a desired engine speed. The controller is also configured to selectively regulate the actuator to adjust a timing of the engine valve to control an amount of air/fuel mixture delivered to the cylinder based on the comparison.

  6. ETHERNET BASED EMBEDDED IOC FOR FEL CONTROL SYSTEM

    SciTech Connect

    Jianxun Yan; Daniel Sexton; Albert Grippo; Steven Moore; Kevin Jordan

    2008-01-23

    An Ethernet based embedded Input Output Controller (IOC) has been developed to upgrade the control system for the Free Electron Laser Project at Jefferson Lab. The embedded IOC, called the Single Board IOC (SBIOC), was integrated with a ColdFire embedded microprocessor and a Field Programmable Gate Array (FPGA) on a circuit board, which can be easily configured to control different kinds of I/O devices. The SBIOC provided features of a complete System-on-Module (SOM) as a stand alone system with abundant high speed I/O ports to couple with suitable devices. The software kits, Experimental Physics and Industrial Control System (EPICS) and Real Time Executive for Multiprocessor System (RTEMS), were chosen to work with our existing control system. The embedded IOC system has the features of a low cost IOC, free open source RTOS, plug-and-play-like ease of installation and flexibility.

  7. Engine control system having fuel-based adjustment

    DOEpatents

    Willi, Martin L.; Fiveland, Scott B.; Montgomery, David T.; Gong, Weidong

    2011-03-15

    A control system for an engine having a cylinder is disclosed having an engine valve configured to affect a fluid flow of the cylinder, an actuator configured to move the engine valve, and an in-cylinder sensor configured to generate a signal indicative of a characteristic of fuel entering the cylinder. The control system also has a controller in communication with the actuator and the sensor. The controller is configured to determine the characteristic of the fuel based on the signal and selectively regulate the actuator to adjust a timing of the engine valve based on the characteristic of the fuel.

  8. Information fusion based optimal control for large civil aircraft system.

    PubMed

    Zhen, Ziyang; Jiang, Ju; Wang, Xinhua; Gao, Chen

    2015-03-01

    Wind disturbance has a great influence on landing security of Large Civil Aircraft. Through simulation research and engineering experience, it can be found that PID control is not good enough to solve the problem of restraining the wind disturbance. This paper focuses on anti-wind attitude control for Large Civil Aircraft in landing phase. In order to improve the riding comfort and the flight security, an information fusion based optimal control strategy is presented to restrain the wind in landing phase for maintaining attitudes and airspeed. Data of Boeing707 is used to establish a nonlinear mode with total variables of Large Civil Aircraft, and then two linear models are obtained which are divided into longitudinal and lateral equations. Based on engineering experience, the longitudinal channel adopts PID control and C inner control to keep longitudinal attitude constant, and applies autothrottle system for keeping airspeed constant, while an information fusion based optimal regulator in the lateral control channel is designed to achieve lateral attitude holding. According to information fusion estimation, by fusing hard constraint information of system dynamic equations and the soft constraint information of performance index function, optimal estimation of the control sequence is derived. Based on this, an information fusion state regulator is deduced for discrete time linear system with disturbance. The simulation results of nonlinear model of aircraft indicate that the information fusion optimal control is better than traditional PID control, LQR control and LQR control with integral action, in anti-wind disturbance performance in the landing phase.

  9. Task Delegation Based Access Control Models for Workflow Systems

    NASA Astrophysics Data System (ADS)

    Gaaloul, Khaled; Charoy, François

    e-Government organisations are facilitated and conducted using workflow management systems. Role-based access control (RBAC) is recognised as an efficient access control model for large organisations. The application of RBAC in workflow systems cannot, however, grant permissions to users dynamically while business processes are being executed. We currently observe a move away from predefined strict workflow modelling towards approaches supporting flexibility on the organisational level. One specific approach is that of task delegation. Task delegation is a mechanism that supports organisational flexibility, and ensures delegation of authority in access control systems. In this paper, we propose a Task-oriented Access Control (TAC) model based on RBAC to address these requirements. We aim to reason about task from organisational perspectives and resources perspectives to analyse and specify authorisation constraints. Moreover, we present a fine grained access control protocol to support delegation based on the TAC model.

  10. Adaptive Neural Network Based Control of Noncanonical Nonlinear Systems.

    PubMed

    Zhang, Yanjun; Tao, Gang; Chen, Mou

    2016-09-01

    This paper presents a new study on the adaptive neural network-based control of a class of noncanonical nonlinear systems with large parametric uncertainties. Unlike commonly studied canonical form nonlinear systems whose neural network approximation system models have explicit relative degree structures, which can directly be used to derive parameterized controllers for adaptation, noncanonical form nonlinear systems usually do not have explicit relative degrees, and thus their approximation system models are also in noncanonical forms. It is well-known that the adaptive control of noncanonical form nonlinear systems involves the parameterization of system dynamics. As demonstrated in this paper, it is also the case for noncanonical neural network approximation system models. Effective control of such systems is an open research problem, especially in the presence of uncertain parameters. This paper shows that it is necessary to reparameterize such neural network system models for adaptive control design, and that such reparameterization can be realized using a relative degree formulation, a concept yet to be studied for general neural network system models. This paper then derives the parameterized controllers that guarantee closed-loop stability and asymptotic output tracking for noncanonical form neural network system models. An illustrative example is presented with the simulation results to demonstrate the control design procedure, and to verify the effectiveness of such a new design method.

  11. RFID - based Staff Control System (SCS) in Kazakhstan

    NASA Astrophysics Data System (ADS)

    Saparkhojayev, N.

    2015-06-01

    RFID - based Staff Control System (SCS) will allow complete hands-free access control, monitoring the whereabouts of employee and record the attendance of the employee as well. Moreover, with a help of this system, it is possible to have a nice report at the end of the month and based on the total number of worked hours, the salary will be allocated to each personnel. The access tag can be read up to 10 centimeters from the RFID reader. The proposed system is based on UHF RFID readers, supported with antennas at gate and transaction sections, and employee identification cards containing RFID-transponders which are able to electronically store information that can be read / written even without the physical contact with the help of radio medium. This system is an innovative system, which describes the benefits of applying RFID- technology in the Education System process of Republic of Kazakhstan. This paper presents the experiments conducted to set up RFID based SCS.

  12. Adaptive control with an expert system based supervisory level. Thesis

    NASA Technical Reports Server (NTRS)

    Sullivan, Gerald A.

    1991-01-01

    Adaptive control is presently one of the methods available which may be used to control plants with poorly modelled dynamics or time varying dynamics. Although many variations of adaptive controllers exist, a common characteristic of all adaptive control schemes, is that input/output measurements from the plant are used to adjust a control law in an on-line fashion. Ideally the adjustment mechanism of the adaptive controller is able to learn enough about the dynamics of the plant from input/output measurements to effectively control the plant. In practice, problems such as measurement noise, controller saturation, and incorrect model order, to name a few, may prevent proper adjustment of the controller and poor performance or instability result. In this work we set out to avoid the inadequacies of procedurally implemented safety nets, by introducing a two level control scheme in which an expert system based 'supervisor' at the upper level provides all the safety net functions for an adaptive controller at the lower level. The expert system is based on a shell called IPEX, (Interactive Process EXpert), that we developed specifically for the diagnosis and treatment of dynamic systems. Some of the more important functions that the IPEX system provides are: (1) temporal reasoning; (2) planning of diagnostic activities; and (3) interactive diagnosis. Also, because knowledge and control logic are separate, the incorporation of new diagnostic and treatment knowledge is relatively simple. We note that the flexibility available in the system to express diagnostic and treatment knowledge, allows much greater functionality than could ever be reasonably expected from procedural implementations of safety nets. The remainder of this chapter is divided into three sections. In section 1.1 we give a detailed review of the literature in the area of supervisory systems for adaptive controllers. In particular, we describe the evolution of safety nets from simple ad hoc techniques, up

  13. Modeling mandatory access control in role-based security systems

    SciTech Connect

    Nyanchama, M.; Osborn, S.

    1996-12-31

    This paper discusses the realization of mandatory access control in role-based protection systems. Starting from the basic definitions of roles, their application in security and the basics of the concept of mandatory access control, we develop a scheme of role-based protection that realizes mandatory access control. The basis of this formulation develops from the recognition that roles can be seen as facilitating access to some given information context. By handling each of the role contexts as independent security levels of information, we simulate mandatory access by imposing the requirements of mandatory access control. Among the key considerations, we propose a means of taming Trojan horses by imposing acyclic information flow among contexts in role-based protection systems. The acyclic information flows and suitable access rules incorporate secrecy which is an essential component of mandatory access control.

  14. Engine control system having fuel-based timing

    DOEpatents

    Willi, Martin L.; Fiveland, Scott B.; Montgomery, David T.; Gong, Weidong

    2012-04-03

    A control system for an engine having a cylinder is disclosed having an engine valve movable to regulate a fluid flow of the cylinder and an actuator associated with the engine valve. The control system also has a sensor configured to generate a signal indicative of an amount of an air/fuel mixture remaining within the cylinder after completion of a first combustion event and a controller in communication with the actuator and the sensor. The controller may be configured to compare the amount with a desired amount, and to selectively regulate the actuator to adjust a timing of the engine valve associated with a subsequent combustion event based on the comparison.

  15. A Realization of Motion Copying System Based on Multilateral Control

    NASA Astrophysics Data System (ADS)

    Yokokura, Yuki; Katsura, Seiichiro; Ohishi, Kiyoshi

    This paper proposes a motion copying system in order to reproduce motion of human operators. The motion copying system consists of both motion saving system and motion loading system based on multilateral controller. The motion saving system is realized by master systems and a slave system. The motion saving system saves motion of a slave system when human operator moves the master systems. At the same time, identity ratio is introduced to decouple the masters motions. The identity ratio of each master system is calculated by force of all master systems, and are saved to memory. On the contrary, real-world master systems and a virtual-world slave system realize the motion loading system. The motion loading system reproduces the motion using saved motion data and value of the identity ratio. The paper confirms that the motion saving system and motion loading system based on multilateral controller is generalized. The reproduced position and force correspond to the saved ones by the proposed method.

  16. Context-Based E-Health System Access Control Mechanism

    NASA Astrophysics Data System (ADS)

    Al-Neyadi, Fahed; Abawajy, Jemal H.

    E-Health systems logically demand a sufficiently fine-grained authorization policy for access control. The access to medical information should not be just role-based but should also include the contextual condition of the role to access data. In this paper, we present a mechanism to extend the standard role-based access control to incorporate contextual information for making access control decisions in e-health application. We present an architecture consisting of authorisation and context infrastructure that work cooperatively to grant access rights based on context-aware authorization policies and context information.

  17. Control System for a Diesel Generator and UPS Based Microgrid

    NASA Astrophysics Data System (ADS)

    Palamar, Andriy; Pettai, Elmo; Beldjajev, Viktor

    2010-01-01

    In this paper a microgrid composed of a diesel generator and two uninterruptible power supply systems with separate battery banks is introduced. The microgrid located in three academic buildings of Tallinn University of Technology. A three-level control and monitoring system for the microgrid based on the EtherNet/IP communication network is developed. In addition, a control strategy of the microgrid in the grid-connected and stand-alone mode of operation is proposed.

  18. Development of a novel disturbance observer based fractional order PD controller for a gun control system.

    PubMed

    Gao, Qiang; Zheng, Liang; Chen, Jilin; Wang, Li; Hou, Yuanlong

    2014-01-01

    Motion control of gun barrels is an ongoing topic for the development of gun control equipment (GCE) with excellent performances. In this paper, a novel disturbance observer (DOB) based fractional order PD (FOPD) control strategy is proposed for the GCE. By adopting the DOB, the control system behaves as if it were the nominal closed-loop system in the absence of disturbances and uncertainties. The optimal control parameters of the FOPD are determined from the loop-shaping perspective, and the Q-filter of the DOB is deliberately designed with consideration of system robustness. The linear frame of the proposed control system will enable the analysis process more convenient. The disturbance rejection properties and the tracking performances of the control system are investigated by both numerical and experimental tests, the results demonstrate that the proposed DOB based FOPD control system is of more robustness, and it is much more suitable for the gun control system with strong nonlinearity and disturbance.

  19. Engine control system having pressure-based timing

    DOEpatents

    Willi, Martin L.; Fiveland, Scott B.; Montgomery, David T.; Gong, Weidong

    2011-10-04

    A control system for an engine having a first cylinder and a second cylinder is disclosed having a first engine valve movable to regulate a fluid flow of the first cylinder and a first actuator associated with the first engine valve. The control system also has a second engine valve movable to regulate a fluid flow of the second cylinder and a sensor configured to generate a signal indicative of a pressure within the first cylinder. The control system also has a controller that is in communication with the first actuator and the sensor. The controller is configured to compare the pressure within the first cylinder with a desired pressure and selectively regulate the first actuator to adjust a timing of the first engine valve independently of the timing of the second engine valve based on the comparison.

  20. FPGA-based multiprocessor system for injection molding control.

    PubMed

    Muñoz-Barron, Benigno; Morales-Velazquez, Luis; Romero-Troncoso, Rene J; Rodriguez-Donate, Carlos; Trejo-Hernandez, Miguel; Benitez-Rangel, Juan P; Osornio-Rios, Roque A

    2012-01-01

    The plastic industry is a very important manufacturing sector and injection molding is a widely used forming method in that industry. The contribution of this work is the development of a strategy to retrofit control of an injection molding machine based on an embedded system microprocessors sensor network on a field programmable gate array (FPGA) device. Six types of embedded processors are included in the system: a smart-sensor processor, a micro fuzzy logic controller, a programmable logic controller, a system manager, an IO processor and a communication processor. Temperature, pressure and position are controlled by the proposed system and experimentation results show its feasibility and robustness. As validation of the present work, a particular sample was successfully injected. PMID:23202036

  1. ARDOLORES: an Arduino based motors control system for DOLORES

    NASA Astrophysics Data System (ADS)

    Gonzalez, Manuel; Ventura, H.; San Juan, J.; Di Fabrizio, L.

    2014-07-01

    We present ARDOLORES a custom made motor control system for the DOLORES instrument in use at the TNG telescope. ARDOLORES replaced the original PMAC based motor control system at a fraction of the cost. The whole system is composed by one master Arduino ONE with its Ethernet shield, to handle the communications with the external world through an Ethernet socket, and by one Arduino ONE with its custom motor shield for each axis to be controlled. The communication between the master and slaves Arduinos is made possible through the I2C bus. Also a Java web-service has been written to control the motors from an higher level and provides an external API for the scientific GUI. The system has been working since January 2012 handling the DOLORES motors and has demonstrated to be stable, reliable, and with easy maintenance in both the hardware and the software parts.

  2. FPGA-Based Multiprocessor System for Injection Molding Control

    PubMed Central

    Muñoz-Barron, Benigno; Morales-Velazquez, Luis; Romero-Troncoso, Rene J.; Rodriguez-Donate, Carlos; Trejo-Hernandez, Miguel; Benitez-Rangel, Juan P.; Osornio-Rios, Roque A.

    2012-01-01

    The plastic industry is a very important manufacturing sector and injection molding is a widely used forming method in that industry. The contribution of this work is the development of a strategy to retrofit control of an injection molding machine based on an embedded system microprocessors sensor network on a field programmable gate array (FPGA) device. Six types of embedded processors are included in the system: a smart-sensor processor, a micro fuzzy logic controller, a programmable logic controller, a system manager, an IO processor and a communication processor. Temperature, pressure and position are controlled by the proposed system and experimentation results show its feasibility and robustness. As validation of the present work, a particular sample was successfully injected. PMID:23202036

  3. View northeast of a microchip based computer control system installed ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View northeast of a microchip based computer control system installed in the early 1980's to replace Lamokin Tower, at center of photograph; panels 1 and 2 at right of photograph are part of main supervisory board; panel 1 controlled Allen Lane sub-station #7; responsiblity for this portion of the system was transferred to southeast Pennsylvania transit authority (septa) in 1985; panel 2 at extreme right controls catenary switches in a coach storage yard adjacent to the station - Thirtieth Street Station, Power Director Center, Thirtieth & Market Streets in Amtrak Railroad Station, Philadelphia, Philadelphia County, PA

  4. [A skin cell segregating control system based on PC].

    PubMed

    Liu, Wen-zhong; Zhou, Ming; Zhang, Hong-bing

    2005-11-01

    A skin cell segregating control system based on PC (personal computer) is presented in this paper. Its front controller is a single-chip microcomputer which enables the manipulation for 6 patients simultaneously, and thus provides a great convenience for clinical treatments for vitiligo. With the use of serial port communication technology, it's possible to monitor and control the front controller in a PC terminal. And the application of computer image acquisition technology realizes the synchronous acquisition of pathologic shin cell images pre/after the operation and a case history. Clinical tests prove its conformity with national standards and the pre-set technological requirements.

  5. Planner-Based Control of Advanced Life Support Systems

    NASA Technical Reports Server (NTRS)

    Muscettola, Nicola; Kortenkamp, David; Fry, Chuck; Bell, Scott

    2005-01-01

    The paper describes an approach to the integration of qualitative and quantitative modeling techniques for advanced life support (ALS) systems. Developing reliable control strategies that scale up to fully integrated life support systems requires augmenting quantitative models and control algorithms with the abstractions provided by qualitative, symbolic models and their associated high-level control strategies. This will allow for effective management of the combinatorics due to the integration of a large number of ALS subsystems. By focusing control actions at different levels of detail and reactivity we can use faster: simpler responses at the lowest level and predictive but complex responses at the higher levels of abstraction. In particular, methods from model-based planning and scheduling can provide effective resource management over long time periods. We describe reference implementation of an advanced control system using the IDEA control architecture developed at NASA Ames Research Center. IDEA uses planning/scheduling as the sole reasoning method for predictive and reactive closed loop control. We describe preliminary experiments in planner-based control of ALS carried out on an integrated ALS simulation developed at NASA Johnson Space Center.

  6. Passivity-based Robust Control of Aerospace Systems

    NASA Technical Reports Server (NTRS)

    Kelkar, Atul G.; Joshi, Suresh M. (Technical Monitor)

    2000-01-01

    This report provides a brief summary of the research work performed over the duration of the cooperative research agreement between NASA Langley Research Center and Kansas State University. The cooperative agreement which was originally for the duration the three years was extended by another year through no-cost extension in order to accomplish the goals of the project. The main objective of the research was to develop passivity-based robust control methodology for passive and non-passive aerospace systems. The focus of the first-year's research was limited to the investigation of passivity-based methods for the robust control of Linear Time-Invariant (LTI) single-input single-output (SISO), open-loop stable, minimum-phase non-passive systems. The second year's focus was mainly on extending the passivity-based methodology to a larger class of non-passive LTI systems which includes unstable and nonminimum phase SISO systems. For LTI non-passive systems, five different passification. methods were developed. The primary effort during the years three and four was on the development of passification methodology for MIMO systems, development of methods for checking robustness of passification, and developing synthesis techniques for passifying compensators. For passive LTI systems optimal synthesis procedure was also developed for the design of constant-gain positive real controllers. For nonlinear passive systems, numerical optimization-based technique was developed for the synthesis of constant as well as time-varying gain positive-real controllers. The passivity-based control design methodology developed during the duration of this project was demonstrated by its application to various benchmark examples. These example systems included longitudinal model of an F-18 High Alpha Research Vehicle (HARV) for pitch axis control, NASA's supersonic transport wind tunnel model, ACC benchmark model, 1-D acoustic duct model, piezo-actuated flexible link model, and NASA

  7. Analysis the robustness of control systems based on disturbance observer

    NASA Astrophysics Data System (ADS)

    Sariyildiz, Emre; Ohnishi, Kouhei

    2013-10-01

    Disturbance observer (DOB) estimates the system disturbances by using the inverse of the nominal plant model and a low pass filter (LPF). Although the LPF provides the properness in the inner-loop, it is the main design constraint of the control systems based on DOB. The bandwidth of the LPF is designed as high as possible so that the DOB can estimate the disturbances in a wider frequency range. However, its bandwidth is limited by noise and robustness of the system. The robustness limitation is directly related with the robustness analysis methods, and they significantly affect the performance of the DOB based control systems. In this paper, three different robustness analysis methods are implemented into the DOB based control systems, and the relation between the robustness of the system and bandwidth of DOB is clearly explained. The conservatism, which is the main drawback of the conventional analysis methods, on the bandwidth of DOB is removed by proposing a new real parametric uncertainty based analysis method. The proposed methods are compared in detail, and simulation results are given to show the validation.

  8. Quantum synchronization in an optomechanical system based on Lyapunov control

    NASA Astrophysics Data System (ADS)

    Li, Wenlin; Li, Chong; Song, Heshan

    2016-06-01

    We extend the concepts of quantum complete synchronization and phase synchronization, which were proposed in A. Mari et al., Phys. Rev. Lett. 111, 103605 (2013), 10.1103/PhysRevLett.111.103605, to more widespread quantum generalized synchronization. Generalized synchronization can be considered a necessary condition or a more flexible derivative of complete synchronization, and its criterion and synchronization measure are proposed and analyzed in this paper. As examples, we consider two typical generalized synchronizations in a designed optomechanical system. Unlike the effort to construct a special coupling synchronization system, we purposefully design extra control fields based on Lyapunov control theory. We find that the Lyapunov function can adapt to more flexible control objectives, which is more suitable for generalized synchronization control, and the control fields can be achieved simply with a time-variant voltage. Finally, the existence of quantum entanglement in different generalized synchronizations is also discussed.

  9. Two-Step Design Method of Engine Control System Based on Generalized Predictive Control

    NASA Astrophysics Data System (ADS)

    Hashimoto, Seiji; Okuda, Hiroyuki; Okada, Yasushi; Adachi, Shuichi; Niwa, Shinji; Kajitani, Mitsunobu

    Conservation of the environment has become critical to the automotive industry. Recently, requirements for on-board diagnostic and engine control systems have been strictly enforced. In the present paper, in order to meet the requirements for a low-emissions vehicle, a novel construction method of the air-fuel ratio (A/F) control system is proposed. The construction method of the system is divided into two steps. The first step is to design the A/F control system for the engine based on an open loop design. The second step is to design the A/F control system for the catalyst system. The design method is based on the generalized predictive control in order to satisfy the robustness to open loop control as well as model uncertainty. The effectiveness of the proposed A/F control system is verified through experiments using full-scale products.

  10. Vote Stuffing Control in IPTV-based Recommender Systems

    NASA Astrophysics Data System (ADS)

    Bhatt, Rajen

    Vote stuffing is a general problem in the functioning of the content rating-based recommender systems. Currently IPTV viewers browse various contents based on the program ratings. In this paper, we propose a fuzzy clustering-based approach to remove the effects of vote stuffing and consider only the genuine ratings for the programs over multiple genres. The approach requires only one authentic rating, which is generally available from recommendation system administrators or program broadcasters. The entire process is automated using fuzzy c-means clustering. Computational experiments performed over one real-world program rating database shows that the proposed approach is very efficient for controlling vote stuffing.

  11. Photoelectric radar servo control system based on ARM+FPGA

    NASA Astrophysics Data System (ADS)

    Wu, Kaixuan; Zhang, Yue; Li, Yeqiu; Dai, Qin; Yao, Jun

    2016-01-01

    In order to get smaller, faster, and more responsive requirements of the photoelectric radar servo control system. We propose a set of core ARM + FPGA architecture servo controller. Parallel processing capability of FPGA to be used for the encoder feedback data, PWM carrier modulation, A, B code decoding processing and so on; Utilizing the advantage of imaging design in ARM Embedded systems achieves high-speed implementation of the PID algorithm. After the actual experiment, the closed-loop speed of response of the system cycles up to 2000 times/s, in the case of excellent precision turntable shaft, using a PID algorithm to achieve the servo position control with the accuracy of + -1 encoder input code. Firstly, This article carry on in-depth study of the embedded servo control system hardware to determine the ARM and FPGA chip as the main chip with systems based on a pre-measured target required to achieve performance requirements, this article based on ARM chip used Samsung S3C2440 chip of ARM7 architecture , the FPGA chip is chosen xilinx's XC3S400 . ARM and FPGA communicate by using SPI bus, the advantage of using SPI bus is saving a lot of pins for easy system upgrades required thereafter. The system gets the speed datas through the photoelectric-encoder that transports the datas to the FPGA, Then the system transmits the datas through the FPGA to ARM, transforms speed datas into the corresponding position and velocity data in a timely manner, prepares the corresponding PWM wave to control motor rotation by making comparison between the position data and the velocity data setted in advance . According to the system requirements to draw the schematics of the photoelectric radar servo control system and PCB board to produce specially. Secondly, using PID algorithm to control the servo system, the datas of speed obtained from photoelectric-encoder is calculated position data and speed data via high-speed digital PID algorithm and coordinate models. Finally, a

  12. Intelligent control system based on ARM for lithography tool

    NASA Astrophysics Data System (ADS)

    Chen, Changlong; Tang, Xiaoping; Hu, Song; Wang, Nan

    2014-08-01

    The control system of traditional lithography tool is based on PC and MCU. The PC handles the complex algorithm, human-computer interaction, and communicates with MCU via serial port; The MCU controls motors and electromagnetic valves, etc. This mode has shortcomings like big volume, high power consumption, and wasting of PC resource. In this paper, an embedded intelligent control system of lithography tool, based on ARM, is provided. The control system used S5PV210 as processor, completing the functions of PC in traditional lithography tool, and provided a good human-computer interaction by using LCD and capacitive touch screen. Using Android4.0.3 as operating system, the equipment provided a cool and easy UI which made the control more user-friendly, and implemented remote control and debug, pushing video information of product by network programming. As a result, it's convenient for equipment vendor to provide technical support for users. Finally, compared with traditional lithography tool, this design reduced the PC part, making the hardware resources efficiently used and reducing the cost and volume. Introducing embedded OS and the concepts in "The Internet of things" into the design of lithography tool can be a development trend.

  13. Design of a synchronization control system for lithography based on repetitive control method

    NASA Astrophysics Data System (ADS)

    Hao, Zhongyang; Peng, Guiyong; Li, Xin; Chen, Xinglin

    2013-01-01

    A repetitive control theory is proposed to solve the synchronization problem between the wafer stage and reticle stage. A macro-micro control method is used based on a macro-micro control structure in which a linear motor is combined with a voice coil motor. A synchronization controller of the reticle stage is added base on the conventional PID control system. The repetitive controller is designed based on the repeated movement of the reticle stage and the wafer stage during the scan and exposure period, and the effects of synchronization control system can be improved because of the repetitive control can effectively track and inhibit the periodicity excitation signal. The repetitive control system effectively reduces the synchronization error during the scan and exposure period,in the meanwhile keep the tracking accuracy and dynamic characters. Simulation results show that the synchronization error can be reduced effectively.

  14. FPGA systems development based on universal controller module

    NASA Astrophysics Data System (ADS)

    Graczyk, Rafał; Pożniak, Krzysztof T.; Romaniuk, Ryszard S.

    2008-01-01

    This paper describes hardware and software concept of Universal Controller Module (UCM), a FPGA/PowerPC based embedded system designed to work as a part of VME system. UCM, on one hand, provides access to the VME crate with various laboratory or industrial interfaces like gigabit optical links, 10/100 Mbit Ethernet, Universal Serial Bus (USB), Controller Area Network (CAN), on the other hand UCM is a well prepared platform for further investigations and development in IP cores field, in functionality expansion by PCI Mezzanine Card (PMC).

  15. DEVS representation of dynamical systems - Event-based intelligent control. [Discrete Event System Specification

    NASA Technical Reports Server (NTRS)

    Zeigler, Bernard P.

    1989-01-01

    It is shown how systems can be advantageously represented as discrete-event models by using DEVS (discrete-event system specification), a set-theoretic formalism. Such DEVS models provide a basis for the design of event-based logic control. In this control paradigm, the controller expects to receive confirming sensor responses to its control commands within definite time windows determined by its DEVS model of the system under control. The event-based contral paradigm is applied in advanced robotic and intelligent automation, showing how classical process control can be readily interfaced with rule-based symbolic reasoning systems.

  16. ETHERNET BASED EMBEDDED SYSTEM FOR FEL DIAGNOSTICS AND CONTROLS

    SciTech Connect

    Jianxun Yan; Daniel Sexton; Steven Moore; Albert Grippo; Kevin Jordan

    2006-10-24

    An Ethernet based embedded system has been developed to upgrade the Beam Viewer and Beam Position Monitor (BPM) systems within the free-electron laser (FEL) project at Jefferson Lab. The embedded microcontroller was mounted on the front-end I/O cards with software packages such as Experimental Physics and Industrial Control System (EPICS) and Real Time Executive for Multiprocessor System (RTEMS) running as an Input/Output Controller (IOC). By cross compiling with the EPICS, the RTEMS kernel, IOC device supports, and databases all of these can be downloaded into the microcontroller. The first version of the BPM electronics based on the embedded controller was built and is currently running in our FEL system. The new version of BPM that will use a Single Board IOC (SBIOC), which integrates with an Field Programming Gate Array (FPGA) and a ColdFire embedded microcontroller, is presently under development. The new system has the features of a low cost IOC, an open source real-time operating system, plug&play-like ease of installation and flexibility, and provides a much more localized solution.

  17. A cooperative control algorithm for camera based observational systems.

    SciTech Connect

    Young, Joseph G.

    2012-01-01

    Over the last several years, there has been considerable growth in camera based observation systems for a variety of safety, scientific, and recreational applications. In order to improve the effectiveness of these systems, we frequently desire the ability to increase the number of observed objects, but solving this problem is not as simple as adding more cameras. Quite often, there are economic or physical restrictions that prevent us from adding additional cameras to the system. As a result, we require methods that coordinate the tracking of objects between multiple cameras in an optimal way. In order to accomplish this goal, we present a new cooperative control algorithm for a camera based observational system. Specifically, we present a receding horizon control where we model the underlying optimal control problem as a mixed integer linear program. The benefit of this design is that we can coordinate the actions between each camera while simultaneously respecting its kinematics. In addition, we further improve the quality of our solution by coupling our algorithm with a Kalman filter. Through this integration, we not only add a predictive component to our control, but we use the uncertainty estimates provided by the filter to encourage the system to periodically observe any outliers in the observed area. This combined approach allows us to intelligently observe the entire region of interest in an effective and thorough manner.

  18. Ideal Based Cyber Security Technical Metrics for Control Systems

    SciTech Connect

    W. F. Boyer; M. A. McQueen

    2007-10-01

    Much of the world's critical infrastructure is at risk from attack through electronic networks connected to control systems. Security metrics are important because they provide the basis for management decisions that affect the protection of the infrastructure. A cyber security technical metric is the security relevant output from an explicit mathematical model that makes use of objective measurements of a technical object. A specific set of technical security metrics are proposed for use by the operators of control systems. Our proposed metrics are based on seven security ideals associated with seven corresponding abstract dimensions of security. We have defined at least one metric for each of the seven ideals. Each metric is a measure of how nearly the associated ideal has been achieved. These seven ideals provide a useful structure for further metrics development. A case study shows how the proposed metrics can be applied to an operational control system.

  19. Neural network based optimal control of HVAC&R systems

    NASA Astrophysics Data System (ADS)

    Ning, Min

    Heating, Ventilation, Air-Conditioning and Refrigeration (HVAC&R) systems have wide applications in providing a desired indoor environment for different types of buildings. It is well acknowledged that 30%-40% of the total energy generated is consumed by buildings and HVAC&R systems alone account for more than 50% of the building energy consumption. Low operational efficiency especially under partial load conditions and poor control are part of reasons for such high energy consumption. To improve energy efficiency, HVAC&R systems should be properly operated to maintain a comfortable and healthy indoor environment under dynamic ambient and indoor conditions with the least energy consumption. This research focuses on the optimal operation of HVAC&R systems. The optimization problem is formulated and solved to find the optimal set points for the chilled water supply temperature, discharge air temperature and AHU (air handling unit) fan static pressure such that the indoor environment is maintained with the least chiller and fan energy consumption. To achieve this objective, a dynamic system model is developed first to simulate the system behavior under different control schemes and operating conditions. The system model is modular in structure, which includes a water-cooled vapor compression chiller model and a two-zone VAV system model. A fuzzy-set based extended transformation approach is then applied to investigate the uncertainties of this model caused by uncertain parameters and the sensitivities of the control inputs with respect to the interested model outputs. A multi-layer feed forward neural network is constructed and trained in unsupervised mode to minimize the cost function which is comprised of overall energy cost and penalty cost when one or more constraints are violated. After training, the network is implemented as a supervisory controller to compute the optimal settings for the system. In order to implement the optimal set points predicted by the

  20. A rule-based neural controller for inverted pendulum system.

    PubMed

    Hao, J; Vandewalle, J; Tan, S

    1993-03-01

    This paper tries to demonstrate how a heuristic neural control approach can be used to solve a complex nonlinear control problem. The control task is to swing up a pendulum mounted on a cart from its stable position (vertically down) to the zero state (up right) and keep it there by applying a sequence of two opposing constant forces of equal magnitude to the mass center of the cart. In addition, the displacement of the cart itself is confined to within a preset limit during the swinging up action and it will eventually be brought to the origin of the track. This is truly a nontrivial nonlinear regulation problem and is considerably difficult compared to the pendulum balancing problem (and its variations) widely adopted as a benchmarking test system for neural controllers. Through the solution of this specific control problem, we try to illustrate a heuristic neural control approach with task decomposition, control rule extraction and neural net rule implementation as its basic elements. Specializing to the pendulum problem, the global control task is decomposed into subtasks namely pendulum positioning and cart positioning. Accordingly, three separate neural subcontrollers are designed to cater to the subtasks and their coordination, i.e., pendulum subcontroller (PSC), cart subcontroller (CSC) and the switching subcontroller (SSC). Each of the subcontrollers is designed based on the rules and guidelines obtained from the experiences of a human operator. The simulation result is included to show the actual performance of the controller.

  1. Lunar Dust Contamination Effects on Lunar Base Thermal Control Systems

    NASA Technical Reports Server (NTRS)

    Keller, John R.; Ewert, Michael K.

    2000-01-01

    Many studies have been conducted to develop a thermal control system that can operate under the extreme thermal environments found on the lunar surface. While these proposed heat rejection systems use different methods to reject heat, each system contains a similar component, a thermal radiator system. These studies have always considered pristine thermal control system components and have overlooked the possible deleterious effects of lunar dust contamination. Since lunar dust has a high emissivity and absorptivity (greater than 0.9) and is opaque, dust accumulation on a surface should radically alter its optical properties and therefore alter its thermal response compared to ideal conditions. In addition, the non-specular nature of the dust particles will alter the performance of systems that employ specular surfaces to enhance heat rejection. To date, few studies have examined the effect of dust deposition on the normal control system components. These studies only focused on a single heat rejection or photovoltaic system. These studies did show that lunar dust accumulations alter the optical properties of any lunar base hardware, which in turn affects component temperatures, and heat rejection. Therefore, a new study was conducted to determine the effect of lunar dust contamination on heat rejection systems. For this study, a previously developed dust deposition model was incorporated into the Thermal Synthesizer System (TSS) model. This modeling scheme incorporates the original method of predicting dust accumulation due to vehicle landings by assuming that the thin dust layer can be treated as a semitransparent surface slightly above and in thermal contact with the pristine surface. The results of this study showed that even small amounts of dust deposits can radically alter the performance of the heat rejection systems. Furthermore. this study indicates that heat rejection systems be either located far from any landing sites or be protected from dust

  2. Type-Based Access Control in Data-Centric Systems

    NASA Astrophysics Data System (ADS)

    Caires, Luís; Pérez, Jorge A.; Seco, João Costa; Vieira, Hugo Torres; Ferrão, Lúcio

    Data-centric multi-user systems, such as web applications, require flexible yet fine-grained data security mechanisms. Such mechanisms are usually enforced by a specially crafted security layer, which adds extra complexity and often leads to error prone coding, easily causing severe security breaches. In this paper, we introduce a programming language approach for enforcing access control policies to data in data-centric programs by static typing. Our development is based on the general concept of refinement type, but extended so as to address realistic and challenging scenarios of permission-based data security, in which policies dynamically depend on the database state, and flexible combinations of column- and row-level protection of data are necessary. We state and prove soundness and safety of our type system, stating that well-typed programs never break the declared data access control policies.

  3. Low-Cost Undergraduate Control Systems Experiments Using Microcontroller-Based Control of a DC Motor

    ERIC Educational Resources Information Center

    Gunasekaran, M.; Potluri, R.

    2012-01-01

    This paper presents low-cost experiments for a control systems laboratory module that is worth one and a third credits. The experiments are organized around the microcontroller-based control of a permanent magnet dc motor. The experimental setups were built in-house. Except for the operating system, the software used is primarily freeware or free…

  4. Cloud-based distributed control of unmanned systems

    NASA Astrophysics Data System (ADS)

    Nguyen, Kim B.; Powell, Darren N.; Yetman, Charles; August, Michael; Alderson, Susan L.; Raney, Christopher J.

    2015-05-01

    Enabling warfighters to efficiently and safely execute dangerous missions, unmanned systems have been an increasingly valuable component in modern warfare. The evolving use of unmanned systems leads to vast amounts of data collected from sensors placed on the remote vehicles. As a result, many command and control (C2) systems have been developed to provide the necessary tools to perform one of the following functions: controlling the unmanned vehicle or analyzing and processing the sensory data from unmanned vehicles. These C2 systems are often disparate from one another, limiting the ability to optimally distribute data among different users. The Space and Naval Warfare Systems Center Pacific (SSC Pacific) seeks to address this technology gap through the UxV to the Cloud via Widgets project. The overarching intent of this three year effort is to provide three major capabilities: 1) unmanned vehicle control using an open service oriented architecture; 2) data distribution utilizing cloud technologies; 3) a collection of web-based tools enabling analysts to better view and process data. This paper focuses on how the UxV to the Cloud via Widgets system is designed and implemented by leveraging the following technologies: Data Distribution Service (DDS), Accumulo, Hadoop, and Ozone Widget Framework (OWF).

  5. High level language-based robotic control system

    NASA Technical Reports Server (NTRS)

    Rodriguez, Guillermo (Inventor); Kreutz, Kenneth K. (Inventor); Jain, Abhinandan (Inventor)

    1996-01-01

    This invention is a robot control system based on a high level language implementing a spatial operator algebra. There are two high level languages included within the system. At the highest level, applications programs can be written in a robot-oriented applications language including broad operators such as MOVE and GRASP. The robot-oriented applications language statements are translated into statements in the spatial operator algebra language. Programming can also take place using the spatial operator algebra language. The statements in the spatial operator algebra language from either source are then translated into machine language statements for execution by a digital control computer. The system also includes the capability of executing the control code sequences in a simulation mode before actual execution to assure proper action at execution time. The robot's environment is checked as part of the process and dynamic reconfiguration is also possible. The languages and system allow the programming and control of multiple arms and the use of inward/outward spatial recursions in which every computational step can be related to a transformation from one point in the mechanical robot to another point to name two major advantages.

  6. High level language-based robotic control system

    NASA Technical Reports Server (NTRS)

    Rodriguez, Guillermo (Inventor); Kruetz, Kenneth K. (Inventor); Jain, Abhinandan (Inventor)

    1994-01-01

    This invention is a robot control system based on a high level language implementing a spatial operator algebra. There are two high level languages included within the system. At the highest level, applications programs can be written in a robot-oriented applications language including broad operators such as MOVE and GRASP. The robot-oriented applications language statements are translated into statements in the spatial operator algebra language. Programming can also take place using the spatial operator algebra language. The statements in the spatial operator algebra language from either source are then translated into machine language statements for execution by a digital control computer. The system also includes the capability of executing the control code sequences in a simulation mode before actual execution to assure proper action at execution time. The robot's environment is checked as part of the process and dynamic reconfiguration is also possible. The languages and system allow the programming and control of multiple arms and the use of inward/outward spatial recursions in which every computational step can be related to a transformation from one point in the mechanical robot to another point to name two major advantages.

  7. A Behavior Based Control System for Surveillance UAVs

    NASA Astrophysics Data System (ADS)

    Oyekan, John; Lu, Bowen; Li, Bo; Gu, Dongbing; Hu, Huosheng

    Unmanned Aerial Vehicles (UAVs) is required to carry out duties such as surveillance, reconnaissance, search and rescue and security patrol missions. Autonomous operation of UAVs is a key to the success of these missions. In this chapter, we propose to use a behavior based control architecture to implement autonomous operation for UAV surveillance missions. This control architecture consists of two layers: a low level control layer and a behavior layer. The low level control layer decomposes 3D motion of UAVs into several atomic actions, such as yaw, roll, pitch, altitude, and 2D position control. These atomic actions together serve as a basis for the behavior layer. The behavior layer consists of a number of necessary behaviors used for surveillance missions, including take-off, object tracking, hovering, landing, trajectory following, obstacle avoidance amongst other behaviors. These behaviors can be instantiated individually or collectively to fulfill the required missions issued by human operators. To evaluate the proposed control architecture, the commercially available DraganFlyer QuadRotor was used as the UAV platform. With the aid of an indoor positioning system, several atomic actions and a group of behaviors were developed for the DraganFlyer. Real testing experiments were conducted to demonstrate the feasibility and performance of the proposed system.

  8. Modeling and control of fuel cell based distributed generation systems

    NASA Astrophysics Data System (ADS)

    Jung, Jin Woo

    This dissertation presents circuit models and control algorithms of fuel cell based distributed generation systems (DGS) for two DGS topologies. In the first topology, each DGS unit utilizes a battery in parallel to the fuel cell in a standalone AC power plant and a grid-interconnection. In the second topology, a Z-source converter, which employs both the L and C passive components and shoot-through zero vectors instead of the conventional DC/DC boost power converter in order to step up the DC-link voltage, is adopted for a standalone AC power supply. In Topology 1, two applications are studied: a standalone power generation (Single DGS Unit and Two DGS Units) and a grid-interconnection. First, dynamic model of the fuel cell is given based on electrochemical process. Second, two full-bridge DC to DC converters are adopted and their controllers are designed: an unidirectional full-bridge DC to DC boost converter for the fuel cell and a bidirectional full-bridge DC to DC buck/boost converter for the battery. Third, for a three-phase DC to AC inverter without or with a Delta/Y transformer, a discrete-time state space circuit model is given and two discrete-time feedback controllers are designed: voltage controller in the outer loop and current controller in the inner loop. And last, for load sharing of two DGS units and power flow control of two DGS units or the DGS connected to the grid, real and reactive power controllers are proposed. Particularly, for the grid-connected DGS application, a synchronization issue between an islanding mode and a paralleling mode to the grid is investigated, and two case studies are performed. To demonstrate the proposed circuit models and control strategies, simulation test-beds using Matlab/Simulink are constructed for each configuration of the fuel cell based DGS with a three-phase AC 120 V (L-N)/60 Hz/50 kVA and various simulation results are presented. In Topology 2, this dissertation presents system modeling, modified space

  9. Microprocessor-based control systems application in nuclear power plant critical systems

    SciTech Connect

    Shah, M.R.; Nowak, J.B. )

    1992-01-01

    Microprocessor-based control systems have been used in fossil power plants and are receiving greater acceptance for application in nuclear plants. This technology is not new but it does require unique considerations when applied to nuclear power plants. Sargent and Lundy (S and L) has used a microprocessor-based component logic control system (interposing Logic System) for safety- and non-safety-related components in nuclear power plants under construction overseas. Currently, S and L is in the design stage to replace an existing analog control system with a microprocessor-based control system in the U.S. The trend in the industry is to replace systems in existing plants or design new power plants with microprocessor-based control systems.

  10. Integrated windows-based control system for an electron microscope

    NASA Astrophysics Data System (ADS)

    Ruan, Shengyang; Kapp, Oscar H.

    1994-12-01

    A Windows application has been developed for management and operation of beam instruments such as electron or ion microscopes. It provides a facility that allows an operator to manage a complicated instrument with minimal effort, primarily under mouse control. The hardware control components used on similar instruments (e.g., the scanning transmission electron microscopes in our lab), such as toggles, buttons, and potentiometers for adjustments on various scales, are all replaced by the controls of the Windows application and are addressable on a single screen. The new controls in this program (via adjustable software settings) offer speed of response and smooth operation providing tailored control of various instrument parameters. Along with the controls offering single parameter adjustment, a two-dimensional control was developed that allows two parameters to be coupled and addressed simultaneously. This capability provides convenience for such tasks as ``finding the beam'' and directing it to a location of interest on the specimen. Using an icon-based display, this Windows application provides better integrated and more robust information for monitoring instrument status than the indicators and meters of the traditional instrument controls. As a Windows application, this program is naturally able to share the resources of the Windows system and is thus able to link to many other applications such as our image acquisition and processing programs. Computer control provides automatic protection and instant diagnostics for the experimental instrument. This Windows application is fully functional and is in daily use to control a new type of electron microscope developed in our lab.

  11. Distributed Frequency Control of Prosumer-Based Electric Energy Systems

    SciTech Connect

    Nazari, MH; Costello, Z; Feizollahi, MJ; Grijalva, S; Egerstedt, M

    2014-11-01

    In this paper, we propose a distributed frequency regulation framework for prosumer-based electric energy systems, where a prosumer (producer-consumer) is defined as an intelligent agentwhich can produce, consume, and/or store electricity. Despite the frequency regulators being distributed, stability can be ensured while avoiding inter-area oscillations using a limited control effort. To achieve this, a fully distributed one-step model-predictive control protocol is proposed and analyzed, whereby each prosumer communicates solely with its neighbors in the network. The efficacy of the proposed frequency regulation framework is shown through simulations on two real-world electric energy systems of different scale and complexity. We show that prosumers can indeed bring frequency and power deviations to their desired values after small perturbations.

  12. Web based remote monitoring and controlling system for vulnerable environments

    NASA Astrophysics Data System (ADS)

    Thomas, Aparna; George, Minu

    2016-03-01

    The two major areas of concern in industrial establishments are monitoring and security. The remote monitoring and controlling can be established with the help of Web technology. Managers can monitor and control the equipment in the remote area through a web browser. The targeted area includes all type of susceptible environment like gas filling station, research and development laboratories. The environmental parameters like temperature, light intensity, gas etc. can be monitored. Security is a very important factor in an industrial setup. So motion detection feature is added to the system to ensure the security. The remote monitoring and controlling system makes use of the latest, less power consumptive and fast working microcontroller like S3C2440. This system is based on ARM9 and Linux operating system. The ARM9 will collect the sensor data and establish real time video monitoring along with motion detection feature. These captured video data as well as environmental data is transmitted over internet using embedded web server which is integrated within the ARM9 board.

  13. Control Strategies for the DAB Based PV Interface System.

    PubMed

    El-Helw, Hadi M; Al-Hasheem, Mohamed; Marei, Mostafa I

    2016-01-01

    This paper presents an interface system based on the Dual Active Bridge (DAB) converter for Photovoltaic (PV) arrays. Two control strategies are proposed for the DAB converter to harvest the maximum power from the PV array. The first strategy is based on a simple PI controller to regulate the terminal PV voltage through the phase shift angle of the DAB converter. The Perturb and Observe (P&O) Maximum Power Point Tracking (MPPT) technique is utilized to set the reference of the PV terminal voltage. The second strategy presented in this paper employs the Artificial Neural Network (ANN) to directly set the phase shift angle of the DAB converter that results in harvesting maximum power. This feed-forward strategy overcomes the stability issues of the feedback strategy. The proposed PV interface systems are modeled and simulated using MATLAB/SIMULINK and the EMTDC/PSCAD software packages. The simulation results reveal accurate and fast response of the proposed systems. The dynamic performance of the proposed feed-forward strategy outdoes that of the feedback strategy in terms of accuracy and response time. Moreover, an experimental prototype is built to test and validate the proposed PV interface system. PMID:27560138

  14. Control Strategies for the DAB Based PV Interface System

    PubMed Central

    El-Helw, Hadi M.; Al-Hasheem, Mohamed; Marei, Mostafa I.

    2016-01-01

    This paper presents an interface system based on the Dual Active Bridge (DAB) converter for Photovoltaic (PV) arrays. Two control strategies are proposed for the DAB converter to harvest the maximum power from the PV array. The first strategy is based on a simple PI controller to regulate the terminal PV voltage through the phase shift angle of the DAB converter. The Perturb and Observe (P&O) Maximum Power Point Tracking (MPPT) technique is utilized to set the reference of the PV terminal voltage. The second strategy presented in this paper employs the Artificial Neural Network (ANN) to directly set the phase shift angle of the DAB converter that results in harvesting maximum power. This feed-forward strategy overcomes the stability issues of the feedback strategy. The proposed PV interface systems are modeled and simulated using MATLAB/SIMULINK and the EMTDC/PSCAD software packages. The simulation results reveal accurate and fast response of the proposed systems. The dynamic performance of the proposed feed-forward strategy outdoes that of the feedback strategy in terms of accuracy and response time. Moreover, an experimental prototype is built to test and validate the proposed PV interface system. PMID:27560138

  15. Development of a Novel Disturbance Observer Based Fractional Order PD Controller for a Gun Control System

    PubMed Central

    Zheng, Liang; Chen, Jilin; Wang, Li; Hou, Yuanlong

    2014-01-01

    Motion control of gun barrels is an ongoing topic for the development of gun control equipment (GCE) with excellent performances. In this paper, a novel disturbance observer (DOB) based fractional order PD (FOPD) control strategy is proposed for the GCE. By adopting the DOB, the control system behaves as if it were the nominal closed-loop system in the absence of disturbances and uncertainties. The optimal control parameters of the FOPD are determined from the loop-shaping perspective, and the Q-filter of the DOB is deliberately designed with consideration of system robustness. The linear frame of the proposed control system will enable the analysis process more convenient. The disturbance rejection properties and the tracking performances of the control system are investigated by both numerical and experimental tests, the results demonstrate that the proposed DOB based FOPD control system is of more robustness, and it is much more suitable for the gun control system with strong nonlinearity and disturbance. PMID:24616616

  16. Fuzzy control of hydraulic servo system based on DSP

    NASA Astrophysics Data System (ADS)

    He, Juan; Yuan, Song-Yue

    2011-10-01

    On the basis of high-speed switching valve of hydraulic servo system, the complex mathematical model of nonlinear hydraulic servo system was analyzed and constructed. A intelligent Fuzzy control method using TMS320LF2407A DSP chip as primary processor was put forward. The simulation results show that the control strategy has a better effect than the conventional PID control has. And the non-differential control of the system has been basically achieved.

  17. Streetlight Control System Based on Wireless Communication over DALI Protocol

    PubMed Central

    Bellido-Outeiriño, Francisco José; Quiles-Latorre, Francisco Javier; Moreno-Moreno, Carlos Diego; Flores-Arias, José María; Moreno-García, Isabel; Ortiz-López, Manuel

    2016-01-01

    Public lighting represents a large part of the energy consumption of towns and cities. Efficient management of public lighting can entail significant energy savings. This work presents a smart system for managing public lighting networks based on wireless communication and the DALI protocol. Wireless communication entails significant economic savings, as there is no need to install new wiring and visual impacts and damage to the facades of historical buildings in city centers are avoided. The DALI protocol uses bidirectional communication with the ballast, which allows its status to be controlled and monitored at all times. The novelty of this work is that it tackles all aspects related to the management of public lighting: a standard protocol, DALI, was selected to control the ballast, a wireless node based on the IEEE 802.15.4 standard with a DALI interface was designed, a network layer that considers the topology of the lighting network has been developed, and lastly, some user-friendly applications for the control and maintenance of the system by the technical crews of the different towns and cities have been developed. PMID:27128923

  18. Streetlight Control System Based on Wireless Communication over DALI Protocol.

    PubMed

    Bellido-Outeiriño, Francisco José; Quiles-Latorre, Francisco Javier; Moreno-Moreno, Carlos Diego; Flores-Arias, José María; Moreno-García, Isabel; Ortiz-López, Manuel

    2016-01-01

    Public lighting represents a large part of the energy consumption of towns and cities. Efficient management of public lighting can entail significant energy savings. This work presents a smart system for managing public lighting networks based on wireless communication and the DALI protocol. Wireless communication entails significant economic savings, as there is no need to install new wiring and visual impacts and damage to the facades of historical buildings in city centers are avoided. The DALI protocol uses bidirectional communication with the ballast, which allows its status to be controlled and monitored at all times. The novelty of this work is that it tackles all aspects related to the management of public lighting: a standard protocol, DALI, was selected to control the ballast, a wireless node based on the IEEE 802.15.4 standard with a DALI interface was designed, a network layer that considers the topology of the lighting network has been developed, and lastly, some user-friendly applications for the control and maintenance of the system by the technical crews of the different towns and cities have been developed. PMID:27128923

  19. The MSP430-based control system for automatic ELISA tester

    NASA Astrophysics Data System (ADS)

    Zhao, Xinghua; Zhu, Lianqing; Dong, Mingli; Lin, Ting; Niu, Shouwei

    2006-11-01

    This paper introduces the scheme of a control system for a fully automatic ELISA (Enzyme-linked Immunosorbent Assay) tester. This tester is designed to realize the movement and positioning of the robotic arms and the pipettors and to complete the functions of pumping, reading, washing, incubating and so on. It is based on a MSP430 flash chip, a 16-bit MCU manufactured by TI Co, with very low power consumption and powerful functions. This chip is adopted in all devices of the workstation to run the controlling program, to store involved parameters and data, and to drive stepper motors. To the MCUs, motors, sensors, valves and fans are extended. A personal computer (PC) is employed to communicate with the instrument through an interface board. Relevant hardware circuits are provided. Two programs, one running in PC performs users' operation about assay options and results, the other running in MCU initiates the system and waits for commands to drive the mechanisms, are developed. Through various examinations, this control system is proved to be reliable, efficient and flexible.

  20. Supervised start system for microprocessor based appliance controls

    SciTech Connect

    Fowler, D.L.; Kadwell, B.J.

    1986-12-09

    A supervisory start system is described for an appliance control that includes a microprocessor, manually actuatable keyboard switch means, and first and second relay means; the microprocessor including first, second and third input means and first, second and third output means and being conditioned to generate control signals at the output means upon receipt of electrical signals at the input means; the supervisory start circuit comprising, in combination, first, second and third transistors each having a base, an emitter and a collector. The first transistor means controls energization of the first relay means and is controlled by the manually actuatable switch means; the manually actuatable switch means being electrically connected to the first output means of the microprocessor and the base of the first transistor; the base of the second transistor being connected to the second output means of the microprocessor, the emitter of the second transistor being connected to a source of potential, the collector of the second transistor being connected to the emitter of the first transistor; the collector of the first transistor being connected to the first relay means; the second transistor being operable to connect the emitter of the first transistor to the source of potential when a signal from the second output means of the microprocessor is applied to the base of the second transistor; the microprocessor being conditioned to emit a signal at the second output means upon receipt of a signal at the first input means; means for latching the first transistor in a conducting condition upon being energized; and means for applying an electrical signal to the second input means when the first transistor means is in a conducting condition.

  1. Apparatus for controlling system state based on unique identifiers

    DOEpatents

    Drotning, William D.

    2002-01-01

    An apparatus allows workers to assert and release control over the energization of a system. The apparatus does not require the workers to carry any additional paraphernalia, and is not be easily defeated by other workers. Users asserting and releasing control present tokens uniquely identifying each user to a reader, and the apparatus prevents transition of the system to an undesired state until an appropriate number of users are currently asserting control. For example, a dangerous manufacturing robot can be prevented from energizing until all the users that have asserted control when entering the robot's controlled space have subsequently released control when leaving the robot's controlled space.

  2. Cooperative wireless network control based health and activity monitoring system.

    PubMed

    Prakash, R; Ganesh, A Balaji; Girish, Siva V

    2016-10-01

    A real-time cooperative communication based wireless network is presented for monitoring health and activity of an end-user in their environment. The cooperative communication offers better energy consumption and also an opportunity to aware the current location of a user non-intrusively. The link between mobile sensor node and relay node is dynamically established by using Received Signal Strength Indicator (RSSI) and Link Quality Indicator (LQI) based on adaptive relay selection scheme. The study proposes a Linear Acceleration based Transmission Power Decision Control (LA-TPDC) algorithm to further enhance the energy efficiency of cooperative communication. Further, the occurrences of false alarms are carefully prevented by introducing three stages of sequential warning system. The real-time experiments are carried-out by using the nodes, namely mobile sensor node, relay nodes and a destination node which are indigenously developed by using a CC430 microcontroller integrated with an in-built transceiver at 868 MHz. The wireless node performance characteristics, such as energy consumption, Signal-Noise ratio (SNR), Bit Error Rate (BER), Packet Delivery Ratio (PDR) and transmission offset are evaluated for all the participated nodes. The experimental results observed that the proposed linear acceleration based transmission power decision control algorithm almost doubles the battery life time than energy efficient conventional cooperative communication. PMID:27562484

  3. Cooperative wireless network control based health and activity monitoring system.

    PubMed

    Prakash, R; Ganesh, A Balaji; Girish, Siva V

    2016-10-01

    A real-time cooperative communication based wireless network is presented for monitoring health and activity of an end-user in their environment. The cooperative communication offers better energy consumption and also an opportunity to aware the current location of a user non-intrusively. The link between mobile sensor node and relay node is dynamically established by using Received Signal Strength Indicator (RSSI) and Link Quality Indicator (LQI) based on adaptive relay selection scheme. The study proposes a Linear Acceleration based Transmission Power Decision Control (LA-TPDC) algorithm to further enhance the energy efficiency of cooperative communication. Further, the occurrences of false alarms are carefully prevented by introducing three stages of sequential warning system. The real-time experiments are carried-out by using the nodes, namely mobile sensor node, relay nodes and a destination node which are indigenously developed by using a CC430 microcontroller integrated with an in-built transceiver at 868 MHz. The wireless node performance characteristics, such as energy consumption, Signal-Noise ratio (SNR), Bit Error Rate (BER), Packet Delivery Ratio (PDR) and transmission offset are evaluated for all the participated nodes. The experimental results observed that the proposed linear acceleration based transmission power decision control algorithm almost doubles the battery life time than energy efficient conventional cooperative communication.

  4. Reliability-Based Control Design for Uncertain Systems

    NASA Technical Reports Server (NTRS)

    Crespo, Luis G.; Kenny, Sean P.

    2005-01-01

    This paper presents a robust control design methodology for systems with probabilistic parametric uncertainty. Control design is carried out by solving a reliability-based multi-objective optimization problem where the probability of violating design requirements is minimized. Simultaneously, failure domains are optimally enlarged to enable global improvements in the closed-loop performance. To enable an efficient numerical implementation, a hybrid approach for estimating reliability metrics is developed. This approach, which integrates deterministic sampling and asymptotic approximations, greatly reduces the numerical burden associated with complex probabilistic computations without compromising the accuracy of the results. Examples using output-feedback and full-state feedback with state estimation are used to demonstrate the ideas proposed.

  5. TEXSYS. [a knowledge based system for the Space Station Freedom thermal control system test-bed

    NASA Technical Reports Server (NTRS)

    Bull, John

    1990-01-01

    The Systems Autonomy Demonstration Project has recently completed a major test and evaluation of TEXSYS, a knowledge-based system (KBS) which demonstrates real-time control and FDIR for the Space Station Freedom thermal control system test-bed. TEXSYS is the largest KBS ever developed by NASA and offers a unique opportunity for the study of technical issues associated with the use of advanced KBS concepts including: model-based reasoning and diagnosis, quantitative and qualitative reasoning, integrated use of model-based and rule-based representations, temporal reasoning, and scale-up performance issues. TEXSYS represents a major achievement in advanced automation that has the potential to significantly influence Space Station Freedom's design for the thermal control system. An overview of the Systems Autonomy Demonstration Project, the thermal control system test-bed, the TEXSYS architecture, preliminary test results, and thermal domain expert feedback are presented.

  6. Disturbance observer based control system design for inertially stabilized platform

    NASA Astrophysics Data System (ADS)

    Wu, Chunnan; Lin, Zhe

    2012-09-01

    Inertially stabilized platform (ISP) is indispensable for various imaging systems to segregate the base angular movement and achieve high LOS (Line-Of-Sight) stability. The disturbance rejection ratio and command following performance are of primary concern in designing ISP control systems. In this paper, the redundant gimbals ISP system is considered and it is shown to experience complex disturbance and parameter variation during operation. To meet advanced LOS stabilization requirement, a disturbance observer based (DOB) dual-loop controller design for ISP is proposed of which the DOB is the internal-loop. Using a nominal plant model and a low-pass filter, the disturbance signal is estimated and used as a cancellation input added to the current command of torque motor. If the DOB works well, the disturbance torque and mismatch between nominal plant and actual plant will be compensated and the internal-loop will behave as nominal model parameters. On the other hand, the external-loop will be designed for nominal model parameters to meet stabilization requirements. This paper will mainly focus on the DOB design method. Since the low-pass filter of DOB determines the sensitivity and complementary sensitivity function as will be shown in this paper, designing the filter is the most important consideration. In this paper, an optimal low-pass filter design method is proposed. The method is intuitive, simple to implement and allows on-line tuning. Simulation results show the performance enhancement of our control structure in the presence of disturbance and measurement noise.

  7. Precision positioning system based on intelligent Fuzzy-PID control

    NASA Astrophysics Data System (ADS)

    Liu, Zhen; Zhang, Liqiong; Li, Yan

    2010-08-01

    To break through the limitations of static and dynamic characteristics of conventional step motor driven open-loop positioning devices, a two-dimensional precision positioning system with a travel range of 100mm×100mm has been developed. This paper presents its structure, control principle and performance experiments. This system, equipped with cross roller guides working as linear guiding elements, is driven by step motors through ball screw transmission. A threeaxis dual-frequency laser interferometric measurement system is established for real-time measurement and feedback of system's movements in three degrees of freedom (DOF) and an intelligent Fuzzy-PID controller is implemented for this system's motion control. In the controller, the PID module calculates the output from motor drivers and its initial parameters are tuned through expansion of critical proportioning method; the Fuzzy module optimizes PID parameters to fulfill specific requirements of different movement stages. A dead zone control mechanism is developed in this controller to minimize the oscillations around target position. Experimental results indicate that system with Fuzzy-PID controller shows faster response than that with ordinary PID controller. Moreover, with this controller implemented, the developed precision positioning system achieves better repeatability (+/-2μm) and accuracy (+/-2.5μm) within the full range than open-loop system using step motor.

  8. Security Encryption Scheme for Communication of Web Based Control Systems

    NASA Astrophysics Data System (ADS)

    Robles, Rosslin John; Kim, Tai-Hoon

    A control system is a device or set of devices to manage, command, direct or regulate the behavior of other devices or systems. The trend in most systems is that they are connected through the Internet. Traditional Supervisory Control and Data Acquisition Systems (SCADA) is connected only in a limited private network Since the internet Supervisory Control and Data Acquisition Systems (SCADA) facility has brought a lot of advantages in terms of control, data viewing and generation. Along with these advantages, are security issues regarding web SCADA, operators are pushed to connect Control Systems through the internet. Because of this, many issues regarding security surfaced. In this paper, we discuss web SCADA and the issues regarding security. As a countermeasure, a web SCADA security solution using crossed-crypto-scheme is proposed to be used in the communication of SCADA components.

  9. The application of intelligent process control to space based systems

    NASA Technical Reports Server (NTRS)

    Wakefield, G. Steve

    1990-01-01

    The application of Artificial Intelligence to electronic and process control can help attain the autonomy and safety requirements of manned space systems. An overview of documented applications within various industries is presented. The development process is discussed along with associated issues for implementing an intelligence process control system.

  10. Fuzzy logic controllers: A knowledge-based system perspective

    NASA Technical Reports Server (NTRS)

    Bonissone, Piero P.

    1993-01-01

    Over the last few years we have seen an increasing number of applications of Fuzzy Logic Controllers. These applications range from the development of auto-focus cameras, to the control of subway trains, cranes, automobile subsystems (automatic transmissions), domestic appliances, and various consumer electronic products. In summary, we consider a Fuzzy Logic Controller to be a high level language with its local semantics, interpreter, and compiler, which enables us to quickly synthesize non-linear controllers for dynamic systems.

  11. Multi-axis control based on movement control cards in NC systems

    NASA Astrophysics Data System (ADS)

    Jiang, Tingbiao; Wei, Yunquan

    2005-12-01

    Today most movement control cards need special control software of topper computers and are only suitable for fixed-axis controls. Consequently, the number of axes which can be controlled is limited. Advanced manufacture technology develops at a very high speed, and that development brings forth. New requirements for movement control in mechanisms and electronics. This paper introduces products of the 5th generation of movement control cards, PMAC 2A-PC/104, made by the Delta Tau Company in the USA. Based on an analysis of PMAC 2A-PC/104, this paper first describes two aspects relevant to the hardware structure of movement control cards and the interrelated software of the topper computers. Then, two methods are presented for solving these problems. The first method is to set limit switches on the movement control cards; all of them can be used to control each moving axis. The second method is to program applied software with existing programming language (for example, VC ++, Visual Basic, Delphi, and so forth). This program is much easier to operate and expand by its users. By using a limit switch, users can choose different axes in movement control cards. Also, users can change parts of the parameters in the control software of topper computers to realize different control axes. Combining these 2 methods proves to be convenient for realizing multi-axis control in numerical control systems.

  12. Adaptive model-based control systems and methods for controlling a gas turbine

    NASA Technical Reports Server (NTRS)

    Brunell, Brent Jerome (Inventor); Mathews, Jr., Harry Kirk (Inventor); Kumar, Aditya (Inventor)

    2004-01-01

    Adaptive model-based control systems and methods are described so that performance and/or operability of a gas turbine in an aircraft engine, power plant, marine propulsion, or industrial application can be optimized under normal, deteriorated, faulted, failed and/or damaged operation. First, a model of each relevant system or component is created, and the model is adapted to the engine. Then, if/when deterioration, a fault, a failure or some kind of damage to an engine component or system is detected, that information is input to the model-based control as changes to the model, constraints, objective function, or other control parameters. With all the information about the engine condition, and state and directives on the control goals in terms of an objective function and constraints, the control then solves an optimization so the optimal control action can be determined and taken. This model and control may be updated in real-time to account for engine-to-engine variation, deterioration, damage, faults and/or failures using optimal corrective control action command(s).

  13. Disturbance Rejection Based Test Rocket Control System Design and Validation

    NASA Astrophysics Data System (ADS)

    Yang, H.; Zhang, S.; Li, T.; Zhang, Y.

    2015-09-01

    This paper presents a novel design and validation for the three-channel attitude controller of a STT test rocket based on the extended state observer approach. The uniform second order integral-chain state space model is firstly established for the control variable of the angle of attack, angle of sideslip and roll angle. Combined with the pole placement, the extended state observer is applied to the disturbance rejection design of the attitude controller. Through numerical and hardware-in-the-loop simulation with uncertainties considered, the effectiveness and robustness of the controller are illustrated and verified. Finally, the performance of the controller is validated by flight-test with satisfactory results.

  14. WELDSMART: A vision-based expert system for quality control

    NASA Technical Reports Server (NTRS)

    Andersen, Kristinn; Barnett, Robert Joel; Springfield, James F.; Cook, George E.

    1992-01-01

    This work was aimed at exploring means for utilizing computer technology in quality inspection and evaluation. Inspection of metallic welds was selected as the main application for this development and primary emphasis was placed on visual inspection, as opposed to other inspection methods, such as radiographic techniques. Emphasis was placed on methodologies with the potential for use in real-time quality control systems. Because quality evaluation is somewhat subjective, despite various efforts to classify discontinuities and standardize inspection methods, the task of using a computer for both inspection and evaluation was not trivial. The work started out with a review of the various inspection techniques that are used for quality control in welding. Among other observations from this review was the finding that most weld defects result in abnormalities that may be seen by visual inspection. This supports the approach of emphasizing visual inspection for this work. Quality control consists of two phases: (1) identification of weld discontinuities (some of which may be severe enough to be classified as defects), and (2) assessment or evaluation of the weld based on the observed discontinuities. Usually the latter phase results in a pass/fail judgement for the inspected piece. It is the conclusion of this work that the first of the above tasks, identification of discontinuities, is the most challenging one. It calls for sophisticated image processing and image analysis techniques, and frequently ad hoc methods have to be developed to identify specific features in the weld image. The difficulty of this task is generally not due to limited computing power. In most cases it was found that a modest personal computer or workstation could carry out most computations in a reasonably short time period. Rather, the algorithms and methods necessary for identifying weld discontinuities were in some cases limited. The fact that specific techniques were finally developed and

  15. Bidimensional MRI-based navigation system using a PID controller.

    PubMed

    Tamaz, Samer; Gourdeau, Richard; Martel, Sylvain

    2006-01-01

    The feasibility of using 2D real-time control to navigate ferromagnetic entities in an MRI bore for novel medical interventions is assessed. Preliminary experimental results confirm that a simple PID controller can be suitable for several applications where targeting out-of-reach locations within the cardiovascular system is essential.

  16. Verification of Spin Magnetic Attitude Control System using air-bearing-based attitude control simulator

    NASA Astrophysics Data System (ADS)

    Ousaloo, H. S.; Nodeh, M. T.; Mehrabian, R.

    2016-09-01

    This paper accomplishes one goal and it was to verify and to validate a Spin Magnetic Attitude Control System (SMACS) program and to perform Hardware-In-the-Loop (HIL) air-bearing experiments. A study of a closed-loop magnetic spin controller is presented using only magnetic rods as actuators. The magnetic spin rate control approach is able to perform spin rate control and it is verified with an Attitude Control System (ACS) air-bearing MATLAB® SIMULINK® model and a hardware-embedded LABVIEW® algorithm that controls the spin rate of the test platform on a spherical air bearing table. The SIMULINK® model includes dynamic model of air-bearing, its disturbances, actuator emulation and the time delays caused by on-board calculations. The air-bearing simulator is employed to develop, improve, and carry out objective tests of magnetic torque rods and spin rate control algorithm in the experimental framework and to provide a more realistic demonstration of expected performance of attitude control as compared with software-based architectures. Six sets of two torque rods are used as actuators for the SMACS. It is implemented and simulated to fulfill mission requirement including spin the satellite up to 12 degs-1 around the z-axis. These techniques are documented for the full nonlinear equations of motion of the system and the performances of these techniques are compared in several simulations.

  17. Microcontroller-based Control Design for Fuel Cell System

    NASA Astrophysics Data System (ADS)

    Firmansyah, I.; Prihandoko, B.; Suwandi, E.

    2009-09-01

    This paper described the hardware design using microcontroller as main part in for fuel cell controller. The system consist of 500 W rated fuel cell stack, a microcontroller and other components such as solenoid valve, proportional valve, cooling pump and sensors. Microcontroller is so easy and effective for this purpose that main function in controlling the fuel cell system can be operated by this chip due to some additional features which is integrated inside it. The microcontroller is not only responsible for controlling the hardware and receiving the measured data such as temperature, pressure, voltage and current but also for communicating with PC to share the data or even receive the set point.

  18. Hierarchical control of ride height system for electronically controlled air suspension based on variable structure and fuzzy control theory

    NASA Astrophysics Data System (ADS)

    Xu, Xing; Zhou, Kongkang; Zou, Nannan; Jiang, Hong; Cui, Xiaoli

    2015-09-01

    The current research of air suspension mainly focuses on the characteristics and design of the air spring. In fact, electronically controlled air suspension (ECAS) has excellent performance in flexible height adjustment during different driving conditions. However, the nonlinearity of the ride height adjusting system and the uneven distribution of payload affect the control accuracy of ride height and the body attitude. Firstly, the three-point measurement system of three height sensors is used to establish the mathematical model of the ride height adjusting system. The decentralized control of ride height and the centralized control of body attitude are presented to design the ride height control system for ECAS. The exact feedback linearization method is adopted for the nonlinear mathematical model of the ride height system. Secondly, according to the hierarchical control theory, the variable structure control (VSC) technique is used to design a controller that is able to adjust the ride height for the quarter-vehicle anywhere, and each quarter-vehicle height control system is independent. Meanwhile, the three-point height signals obtained by three height sensors are tracked to calculate the body pitch and roll attitude over time, and then by calculating the deviation of pitch and roll and its rates, the height control correction is reassigned based on the fuzzy algorithm. Finally, to verify the effectiveness and performance of the proposed combined control strategy, a validating test of ride height control system with and without road disturbance is carried out. Testing results show that the height adjusting time of both lifting and lowering is over 5 s, and the pitch angle and the roll angle of body attitude are less than 0.15°. This research proposes a hierarchical control method that can guarantee the attitude stability, as well as satisfy the ride height tracking system.

  19. Neural network-based finite horizon stochastic optimal control design for nonlinear networked control systems.

    PubMed

    Xu, Hao; Jagannathan, Sarangapani

    2015-03-01

    The stochastic optimal control of nonlinear networked control systems (NNCSs) using neuro-dynamic programming (NDP) over a finite time horizon is a challenging problem due to terminal constraints, system uncertainties, and unknown network imperfections, such as network-induced delays and packet losses. Since the traditional iteration or time-based infinite horizon NDP schemes are unsuitable for NNCS with terminal constraints, a novel time-based NDP scheme is developed to solve finite horizon optimal control of NNCS by mitigating the above-mentioned challenges. First, an online neural network (NN) identifier is introduced to approximate the control coefficient matrix that is subsequently utilized in conjunction with the critic and actor NNs to determine a time-based stochastic optimal control input over finite horizon in a forward-in-time and online manner. Eventually, Lyapunov theory is used to show that all closed-loop signals and NN weights are uniformly ultimately bounded with ultimate bounds being a function of initial conditions and final time. Moreover, the approximated control input converges close to optimal value within finite time. The simulation results are included to show the effectiveness of the proposed scheme. PMID:25720004

  20. Power quality control of an autonomous wind-diesel power system based on hybrid intelligent controller.

    PubMed

    Ko, Hee-Sang; Lee, Kwang Y; Kang, Min-Jae; Kim, Ho-Chan

    2008-12-01

    Wind power generation is gaining popularity as the power industry in the world is moving toward more liberalized trade of energy along with public concerns of more environmentally friendly mode of electricity generation. The weakness of wind power generation is its dependence on nature-the power output varies in quite a wide range due to the change of wind speed, which is difficult to model and predict. The excess fluctuation of power output and voltages can influence negatively the quality of electricity in the distribution system connected to the wind power generation plant. In this paper, the authors propose an intelligent adaptive system to control the output of a wind power generation plant to maintain the quality of electricity in the distribution system. The target wind generator is a cost-effective induction generator, while the plant is equipped with a small capacity energy storage based on conventional batteries, heater load for co-generation and braking, and a voltage smoothing device such as a static Var compensator (SVC). Fuzzy logic controller provides a flexible controller covering a wide range of energy/voltage compensation. A neural network inverse model is designed to provide compensating control amount for a system. The system can be optimized to cope with the fluctuating market-based electricity price conditions to lower the cost of electricity consumption or to maximize the power sales opportunities from the wind generation plant. PMID:18996680

  1. Power quality control of an autonomous wind-diesel power system based on hybrid intelligent controller.

    PubMed

    Ko, Hee-Sang; Lee, Kwang Y; Kang, Min-Jae; Kim, Ho-Chan

    2008-12-01

    Wind power generation is gaining popularity as the power industry in the world is moving toward more liberalized trade of energy along with public concerns of more environmentally friendly mode of electricity generation. The weakness of wind power generation is its dependence on nature-the power output varies in quite a wide range due to the change of wind speed, which is difficult to model and predict. The excess fluctuation of power output and voltages can influence negatively the quality of electricity in the distribution system connected to the wind power generation plant. In this paper, the authors propose an intelligent adaptive system to control the output of a wind power generation plant to maintain the quality of electricity in the distribution system. The target wind generator is a cost-effective induction generator, while the plant is equipped with a small capacity energy storage based on conventional batteries, heater load for co-generation and braking, and a voltage smoothing device such as a static Var compensator (SVC). Fuzzy logic controller provides a flexible controller covering a wide range of energy/voltage compensation. A neural network inverse model is designed to provide compensating control amount for a system. The system can be optimized to cope with the fluctuating market-based electricity price conditions to lower the cost of electricity consumption or to maximize the power sales opportunities from the wind generation plant.

  2. Adaptive mechanism-based congestion control for networked systems

    NASA Astrophysics Data System (ADS)

    Liu, Zhi; Zhang, Yun; Chen, C. L. Philip

    2013-03-01

    In order to assure the communication quality in network systems with heavy traffic and limited bandwidth, a new ATRED (adaptive thresholds random early detection) congestion control algorithm is proposed for the congestion avoidance and resource management of network systems. Different to the traditional AQM (active queue management) algorithms, the control parameters of ATRED are not configured statically, but dynamically adjusted by the adaptive mechanism. By integrating with the adaptive strategy, ATRED alleviates the tuning difficulty of RED (random early detection) and shows a better control on the queue management, and achieve a more robust performance than RED under varying network conditions. Furthermore, a dynamic transmission control protocol-AQM control system using ATRED controller is introduced for the systematic analysis. It is proved that the stability of the network system can be guaranteed when the adaptive mechanism is finely designed. Simulation studies show the proposed ATRED algorithm achieves a good performance in varying network environments, which is superior to the RED and Gentle-RED algorithm, and providing more reliable service under varying network conditions.

  3. PSO based PI controller design for a solar charger system.

    PubMed

    Yau, Her-Terng; Lin, Chih-Jer; Liang, Qin-Cheng

    2013-01-01

    Due to global energy crisis and severe environmental pollution, the photovoltaic (PV) system has become one of the most important renewable energy sources. Many previous studies on solar charger integrated system only focus on load charge control or switching Maximum Power Point Tracking (MPPT) and charge control modes. This study used two-stage system, which allows the overall portable solar energy charging system to implement MPPT and optimal charge control of Li-ion battery simultaneously. First, this study designs a DC/DC boost converter of solar power generation, which uses variable step size incremental conductance method (VSINC) to enable the solar cell to track the maximum power point at any time. The voltage was exported from the DC/DC boost converter to the DC/DC buck converter, so that the voltage dropped to proper voltage for charging the battery. The charging system uses constant current/constant voltage (CC/CV) method to charge the lithium battery. In order to obtain the optimum PI charge controller parameters, this study used intelligent algorithm to determine the optimum parameters. According to the simulation and experimental results, the control parameters resulted from PSO have better performance than genetic algorithms (GAs). PMID:23766713

  4. PSO Based PI Controller Design for a Solar Charger System

    PubMed Central

    Yau, Her-Terng; Lin, Chih-Jer; Liang, Qin-Cheng

    2013-01-01

    Due to global energy crisis and severe environmental pollution, the photovoltaic (PV) system has become one of the most important renewable energy sources. Many previous studies on solar charger integrated system only focus on load charge control or switching Maximum Power Point Tracking (MPPT) and charge control modes. This study used two-stage system, which allows the overall portable solar energy charging system to implement MPPT and optimal charge control of Li-ion battery simultaneously. First, this study designs a DC/DC boost converter of solar power generation, which uses variable step size incremental conductance method (VSINC) to enable the solar cell to track the maximum power point at any time. The voltage was exported from the DC/DC boost converter to the DC/DC buck converter, so that the voltage dropped to proper voltage for charging the battery. The charging system uses constant current/constant voltage (CC/CV) method to charge the lithium battery. In order to obtain the optimum PI charge controller parameters, this study used intelligent algorithm to determine the optimum parameters. According to the simulation and experimental results, the control parameters resulted from PSO have better performance than genetic algorithms (GAs). PMID:23766713

  5. PSO based PI controller design for a solar charger system.

    PubMed

    Yau, Her-Terng; Lin, Chih-Jer; Liang, Qin-Cheng

    2013-01-01

    Due to global energy crisis and severe environmental pollution, the photovoltaic (PV) system has become one of the most important renewable energy sources. Many previous studies on solar charger integrated system only focus on load charge control or switching Maximum Power Point Tracking (MPPT) and charge control modes. This study used two-stage system, which allows the overall portable solar energy charging system to implement MPPT and optimal charge control of Li-ion battery simultaneously. First, this study designs a DC/DC boost converter of solar power generation, which uses variable step size incremental conductance method (VSINC) to enable the solar cell to track the maximum power point at any time. The voltage was exported from the DC/DC boost converter to the DC/DC buck converter, so that the voltage dropped to proper voltage for charging the battery. The charging system uses constant current/constant voltage (CC/CV) method to charge the lithium battery. In order to obtain the optimum PI charge controller parameters, this study used intelligent algorithm to determine the optimum parameters. According to the simulation and experimental results, the control parameters resulted from PSO have better performance than genetic algorithms (GAs).

  6. Statistical process control based chart for information systems security

    NASA Astrophysics Data System (ADS)

    Khan, Mansoor S.; Cui, Lirong

    2015-07-01

    Intrusion detection systems have a highly significant role in securing computer networks and information systems. To assure the reliability and quality of computer networks and information systems, it is highly desirable to develop techniques that detect intrusions into information systems. We put forward the concept of statistical process control (SPC) in computer networks and information systems intrusions. In this article we propose exponentially weighted moving average (EWMA) type quality monitoring scheme. Our proposed scheme has only one parameter which differentiates it from the past versions. We construct the control limits for the proposed scheme and investigate their effectiveness. We provide an industrial example for the sake of clarity for practitioner. We give comparison of the proposed scheme with EWMA schemes and p chart; finally we provide some recommendations for the future work.

  7. MINDS: A microcomputer interactive data system for 8086-based controllers

    NASA Technical Reports Server (NTRS)

    Soeder, J. F.

    1985-01-01

    A microcomputer interactive data system (MINDS) software package for the 8086 family of microcomputers is described. To enhance program understandability and ease of code maintenance, the software is written in PL/M-86, Intel Corporation's high-level system implementation language. The MINDS software is intended to run in residence with real-time digital control software to provide displays of steady-state and transient data. In addition, the MINDS package provides classic monitor capabilities along with extended provisions for debugging an executing control system. The software uses the CP/M-86 operating system developed by Digital Research, Inc., to provide program load capabilities along with a uniform file structure for data and table storage. Finally, a library of input and output subroutines to be used with consoles equipped with PL/M-86 and assembly language is described.

  8. Motion control solution for new PLC-based standard development platform for VLT instrument control systems

    NASA Astrophysics Data System (ADS)

    Popovic, D.; Brast, R.; Di Lieto, N.; Kiekebusch, M.; Knudstrup, J.; Lucuix, C.

    2014-07-01

    More than a decade ago, due to obsolescence issues, ESO initiated the design and implementation of a custom-made CANbus based motion controller (CAN-RMC) to provide, together with a tailor-made software library (motor library), the motion control capabilities for the VME platform needed for the second generation VLT/VLTI instruments. The CAN-RMC controller has been successfully used in a number of VLT instruments but it has high production costs compared to the commercial off-the-shelf (COTS) industrial solutions available on the market today. In the scope of the selection of a new PLC-based platform for the VLT instrument control systems, ESO has evaluated motion control solutions from the company Beckhoff. This paper presents the investigation, implementation and testing of the PLC/TwinCAT/EtherCAT motion controllers for DC and stepper motors and their adaptation and integration into the VLT instrumentation framework. It reports functional and performance test results for the most typical use cases of astronomical instruments like initialization sequences, tracking, switch position detections, backslash compensation, brake handling, etc. In addition, it gives an overview of the main features of TwinCAT NC/PTP, PLCopen MC, EtherCAT motion control terminals and the engineering tools like TwinCAT Scope that are integrated into the development environment and simplify software development, testing and commissioning of motorized instrument functions.

  9. Nonlinear system controller design based on domain of attaction: An application to CELSS analysis and control

    NASA Technical Reports Server (NTRS)

    Babcock, P. S., IV

    1986-01-01

    Nonlinear system controller design based on the domain of attraction is presented. This is particularly suited to investigating Closed Ecological Life Support Systems (CELSS) models. In particular, the dynamic consequences of changes in the waste storage capacity and system mass, and how information is used for control in CELSS models are examined. The models' high dimensionality and nonlinear state equations make them difficult to analyze by any other technique. The domain of attraction is the region in initial conditions that tend toward an attractor and it is delineated by randomly selecting initial conditions from the region of state space being investigated. Error analysis is done by repeating the domain simulations with independent samples. A refinement of this region is the domain of performance which is the region of initial conditions meeting a performance criteria. In nonlinear systems, local stability does not insure stability over a larger region. The domain of attraction marks out this stability region; hence, it can be considered a measure of a nonlinear system's ability to recovery from state perturbations. Considering random perturbations, the minimum radius of the domain is a measure of the magnitude of perturbations for which recovery is guaranteed. Design of both linear and nonlinear controllers are shown. Three CELSS models, with 9 to 30 state variable, are presented. Measures of the domain of attraction are used to show the global behavior of these models under a variety of design and controller scenarios.

  10. Hydrogel-Based Controlled Delivery Systems for Articular Cartilage Repair

    PubMed Central

    Madry, Henning

    2016-01-01

    Delivery of bioactive factors is a very valuable strategy for articular cartilage repair. Nevertheless, the direct supply of such biomolecules is limited by several factors including rapid degradation, the need for supraphysiological doses, the occurrence of immune and inflammatory responses, and the possibility of dissemination to nontarget sites that may impair their therapeutic action and raise undesired effects. The use of controlled delivery systems has the potential of overcoming these hurdles by promoting the temporal and spatial presentation of such factors in a defined target. Hydrogels are promising materials to develop delivery systems for cartilage repair as they can be easily loaded with bioactive molecules controlling their release only where required. This review exposes the most recent technologies on the design of hydrogels as controlled delivery platforms of bioactive molecules for cartilage repair. PMID:27642587

  11. Hydrogel-Based Controlled Delivery Systems for Articular Cartilage Repair.

    PubMed

    Rey-Rico, Ana; Madry, Henning; Cucchiarini, Magali

    2016-01-01

    Delivery of bioactive factors is a very valuable strategy for articular cartilage repair. Nevertheless, the direct supply of such biomolecules is limited by several factors including rapid degradation, the need for supraphysiological doses, the occurrence of immune and inflammatory responses, and the possibility of dissemination to nontarget sites that may impair their therapeutic action and raise undesired effects. The use of controlled delivery systems has the potential of overcoming these hurdles by promoting the temporal and spatial presentation of such factors in a defined target. Hydrogels are promising materials to develop delivery systems for cartilage repair as they can be easily loaded with bioactive molecules controlling their release only where required. This review exposes the most recent technologies on the design of hydrogels as controlled delivery platforms of bioactive molecules for cartilage repair. PMID:27642587

  12. Hydrogel-Based Controlled Delivery Systems for Articular Cartilage Repair

    PubMed Central

    Madry, Henning

    2016-01-01

    Delivery of bioactive factors is a very valuable strategy for articular cartilage repair. Nevertheless, the direct supply of such biomolecules is limited by several factors including rapid degradation, the need for supraphysiological doses, the occurrence of immune and inflammatory responses, and the possibility of dissemination to nontarget sites that may impair their therapeutic action and raise undesired effects. The use of controlled delivery systems has the potential of overcoming these hurdles by promoting the temporal and spatial presentation of such factors in a defined target. Hydrogels are promising materials to develop delivery systems for cartilage repair as they can be easily loaded with bioactive molecules controlling their release only where required. This review exposes the most recent technologies on the design of hydrogels as controlled delivery platforms of bioactive molecules for cartilage repair.

  13. Control of proton exchange membrane fuel cell system breathing based on maximum net power control strategy

    NASA Astrophysics Data System (ADS)

    Li, Qi; Chen, Weirong; Liu, Zhixiang; Guo, Ai; Liu, Shukui

    2013-11-01

    In order to achieve the maximum net power, the analysis for the maximum net power characterization of a proton exchange membrane fuel cell (PEMFC) system is carried out. A maximum net power control (MNPC) strategy based on an implicit generalized predictive control (IGPC) and a reference governor is proposed to keep optimal oxygen excess ratio (OER) trajectory. The IGPC based on an effective informed adaptive particle swarm optimization (EIA-PSO) algorithm is developed to solve the predictive control law and reduce the computational complexity in the rolling optimization process. The simulations of three conditional tests are implemented and the results demonstrate that the proposed strategy can track the optimal OER trajectory, reduce the parasitic power and maximize the output net power. The comprehensive comparisons based on three conditional tests verify that the MNPC-IGPC has better robust performance in the presence of large disturbances, time delay and various noises. The experimental comparison with internal control system of Ballard 1.2 kW Nexa Power Module testifies the validity of the MNPC-IGPC for increasing the net power. Hence, this proposed strategy can provide better behavior to guarantee optimal OER trajectory and the maximum net power even though the disturbances and uncertainties occur.

  14. Privacy and Access Control for IHE-Based Systems

    NASA Astrophysics Data System (ADS)

    Katt, Basel; Breu, Ruth; Hafner, Micahel; Schabetsberger, Thomas; Mair, Richard; Wozak, Florian

    Electronic Health Record (EHR) is the heart element of any e-health system, which aims at improving the quality and efficiency of healthcare through the use of information and communication technologies. The sensitivity of the data contained in the health record poses a great challenge to security. In this paper we propose a security architecture for EHR systems that are conform with IHE profiles. In this architecture we are tackling the problems of access control and privacy. Furthermore, a prototypical implementation of the proposed model is presented.

  15. Object-Coordinate-Based Bilateral Control System Using Visual Information

    NASA Astrophysics Data System (ADS)

    Nakajima, Yu; Nozaki, Takahiro; Oyamada, Yuji; Ohnishi, Kouhei

    In the field of teleoperation, visual or tactile information obtained by the operators is restricted (e. g., limited or delayed sight) because of communication constraints. Therefore, it is difficult for the operators to operate the system. In this paper, a bilateral control system using the environmental information about the position and posture of a target as obtained by a camera is proposed. The proposed method reduces the workload of the operators by taking some of their tasks. An experiment is conducted to prove the benefit of the proposed method by using a 1-DOF master robot and a 2-DOF slave robot.

  16. The representation of knowledge within model-based control systems

    SciTech Connect

    Weygand, D.P.; Koul, R.

    1987-01-01

    Representation of knowledge in artificially intelligent systems is discussed. Types of knowledge that might need to be represented in AI systems are listed, and include knowledge about objects, events, knowledge about how to do things, and knowledge about what human beings know (meta-knowledge). The use of knowledge in AI systems is discussed in terms of acquiring and retrieving knowledge and reasoning about known facts. Different kinds of reasonings or representations are ghen described with some examples given. These include formal reasoning or logical representation, which is related to mathematical logic, production systems, which are based on the idea of condition-action pairs (production), procedural reasoning, which uses pre-formed plans to solve problems, frames, which provide a structure for representing knowledge in an organized manner, direct analogical representations, which represent knowledge in such a manner that permits some observation without deduction. (LEW)

  17. A knowledge-based system for controlling automobile traffic

    NASA Technical Reports Server (NTRS)

    Maravas, Alexander; Stengel, Robert F.

    1994-01-01

    Transportation network capacity variations arising from accidents, roadway maintenance activity, and special events as well as fluctuations in commuters' travel demands complicate traffic management. Artificial intelligence concepts and expert systems can be useful in framing policies for incident detection, congestion anticipation, and optimal traffic management. This paper examines the applicability of intelligent route guidance and control as decision aids for traffic management. Basic requirements for managing traffic are reviewed, concepts for studying traffic flow are introduced, and mathematical models for modeling traffic flow are examined. Measures for quantifying transportation network performance levels are chosen, and surveillance and control strategies are evaluated. It can be concluded that automated decision support holds great promise for aiding the efficient flow of automobile traffic over limited-access roadways, bridges, and tunnels.

  18. Flexible system model reduction and control system design based upon actuator and sensor influence functions

    NASA Technical Reports Server (NTRS)

    Yam, Yeung; Johnson, Timothy L.; Lang, Jeffrey H.

    1987-01-01

    A model reduction technique based on aggregation with respect to sensor and actuator influence functions rather than modes is presented for large systems of coupled second-order differential equations. Perturbation expressions which can predict the effects of spillover on both the reduced-order plant model and the neglected plant model are derived. For the special case of collocated actuators and sensors, these expressions lead to the derivation of constraints on the controller gains that are, given the validity of the perturbation technique, sufficient to guarantee the stability of the closed-loop system. A case study demonstrates the derivation of stabilizing controllers based on the present technique. The use of control and observation synthesis in modifying the dimension of the reduced-order plant model is also discussed. A numerical example is provided for illustration.

  19. Nano-based systems for oil spills control and cleanup.

    PubMed

    Avila, Antonio F; Munhoz, Viviane C; de Oliveira, Aline M; Santos, Mayara C G; Lacerda, Glenda R B S; Gonçalves, Camila P

    2014-05-15

    This paper reports the development of superhydrophobic nanocomposite systems which are also oleophilic. As hydrophobicity is based on low energy surface and surface roughness, the electrospinning technique was selected as the manufacturing technique. N,N' dimethylformamide (DMF) was employed as the polystyrene (PS) solvent. The "Tea-bag" (T-B) nanocomposite system is based on exfoliated graphite surrounded by PS superhydrophobic membranes. The T-B systems were tested regarding its adsorption and absorption rates. To test these properties, it was employed three different water/oil emulsions, i.e., new and used motor oil, which have physical properties (viscosity and specific gravity) similar to heavy crude oil extracted in Brazil, and vacuum pump oil (which does not form oil/water emulsion). It was observed that oil adsorption rate is dependent on oil surface tension, while the absorption rate is mainly dependent on membrane/exfoliated graphite surface area. Experimental data show that oil absorption rates ranged between 2.5g/g and 40g/g, while the adsorption rate oscillated from 0.32g/g/min to 0.80g/g/min. Furthermore, T-B systems were tested as containment barriers and sorbent materials with good results including its recyclability.

  20. A 3D polarizing display system base on backlight control

    NASA Astrophysics Data System (ADS)

    Liu, Pu; Huang, Ziqiang

    2011-08-01

    In this paper a new three-dimensional (3D) liquid crystal display (LCD) display mode based on backlight control is presented to avoid the left and right eye images crosstalk in 3D display. There are two major issues in this new black frame 3D display mode. One is continuously playing every frame images twice. The other is controlling the backlight switch periodically. First, this paper explains the cause of the left and right eye images crosstalk, and presents a solution to avoid this problem. Then, we propose to play the entire frame images twice by repeating each frame image after it was played instead of playing the left images and the right images frame by frame alternately. Finally, the backlight is switched periodically instead of turned on all the time. The backlight is turned off while a frame of image is played for the first time, then turned on during the second time, after that it will be turned off again and run the next period with the next frame of image start to refresh. Controlling the backlight switch periodically like this is the key to achieve the black frame 3D display mode. This mode can not only achieve better 3D display effect by avoid the left and right image crosstalk, but also save the backlight power consumption. Theoretical analysis and experiments show that our method is reasonable and efficient.

  1. Data-Driven Based Asynchronous Motor Control for Printing Servo Systems

    NASA Astrophysics Data System (ADS)

    Bian, Min; Guo, Qingyun

    Modern digital printing equipment aims to the environmental-friendly industry with high dynamic performances and control precision and low vibration and abrasion. High performance motion control system of printing servo systems was required. Control system of asynchronous motor based on data acquisition was proposed. Iterative learning control (ILC) algorithm was studied. PID control was widely used in the motion control. However, it was sensitive to the disturbances and model parameters variation. The ILC applied the history error data and present control signals to approximate the control signal directly in order to fully track the expect trajectory without the system models and structures. The motor control algorithm based on the ILC and PID was constructed and simulation results were given. The results show that data-driven control method is effective dealing with bounded disturbances for the motion control of printing servo systems.

  2. Control and scheduling codesign based on EDF-IAE in networked control systems

    NASA Astrophysics Data System (ADS)

    Yan, Shen; Bing, Guo

    2005-12-01

    Networked control systems are one type of distributed real-time control systems where sensors, actuator and controllers are interconnected by communication networks. In networked control systems, the insertion of the communication network makes the analysis and design of a networked control system more complex. In the past, control system design and CPU scheduling or network scheduling design have normally been separated. But from the point of both the communication protocols and the interacting controlled system, they should not be treated as separate. Thus, a co-design approach is proposed. Firstly, transmission model for the networked control systems is defined when a set of networked control systems is connected to the network, the Rate Monotonic (RM) scheduling algorithm and the Earliest Deadline First (EDF) scheduling algorithm are introduced. Then, applying EDF scheduling algorithm with the Integral of the Absolute Error (IAE) to schedule a set of real-time networked control systems. Finally, a simulation example is given to implement EDF-IAE performance protocol. The simulation results show that EDF-IAE performance protocol is feasible.

  3. Virtual-reality-based system for controlled study of cataplexy

    NASA Astrophysics Data System (ADS)

    Augustine, Kurt E.; Cameron, Bruce M.; Camp, Jon J.; Krahn, Lois E.; Robb, Richard A.

    2002-05-01

    Cataplexy is a sudden loss of voluntary muscle control experienced by narcolepsy patients. It is usually triggered by strong, spontaneous emotions and is more common in times of stress. The Sleep Disorders Unit and the Biomedical Imaging Resource at Mayo Clinic are developing interactive display technology for reliably inducing cataplexy during clinical monitoring. The project is referred to as the Cataplexy/Narcolepsy Activation Program, or CatNAP. We have developed an automobile driving simulation that introduces humorous, surprising, and stress-inducing events and objects as the patient attempts to navigate a vehicle through a virtual town. The patient wears a head-mounted display and controls the vehicle via a driving simulator steering wheel and pedal cluster. As the patient attempts to drive through the town, various objects, sounds or conditions occur that distract, startle, frustrate or amuse. These responses may trigger a cataplectic episode, which can then be clinically evaluated. We believe CatNAP is a novel and innovative example of the effective application of virtual reality technology to study an important clinical problem that has resisted previous approaches. An evaluation phase with volunteer patients previously diagnosed with cataplexy has been completed. The prototype system is being prepared for a full clinical study.

  4. Image-Based Visual Servoing for Robotic Systems: A Nonlinear Lyapunov-Based Control Approach

    SciTech Connect

    Dixon, Warren

    2004-06-01

    There is significant motivation to provide robotic systems with improved autonomy as a means to significantly accelerate deactivation and decommissioning (D&D) operations while also reducing the associated costs, removing human operators from hazardous environments, and reducing the required burden and skill of human operators. To achieve improved autonomy, this project focused on the basic science challenges leading to the development of visual servo controllers. The challenge in developing these controllers is that a camera provides 2-dimensional image information about the 3-dimensional Euclidean-space through a perspective (range dependent) projection that can be corrupted by uncertainty in the camera calibration matrix and by disturbances such as nonlinear radial distortion. Disturbances in this relationship (i.e., corruption in the sensor information) propagate erroneous information to the feedback controller of the robot, leading to potentially unpredictable task execution. This research project focused on the development of a visual servo control methodology that targets compensating for disturbances in the camera model (i.e., camera calibration and the recovery of range information) as a means to achieve predictable response by the robotic system operating in unstructured environments. The fundamental idea is to use nonlinear Lyapunov-based techniques along with photogrammetry methods to overcome the complex control issues and alleviate many of the restrictive assumptions that impact current robotic applications. The outcome of this control methodology is a plug-and-play visual servoing control module that can be utilized in conjunction with current technology such as feature recognition and extraction to enable robotic systems with the capabilities of increased accuracy, autonomy, and robustness, with a larger field of view (and hence a larger workspace). The developed methodology has been reported in numerous peer-reviewed publications and the

  5. System and method for controlling power consumption in a computer system based on user satisfaction

    DOEpatents

    Yang, Lei; Dick, Robert P; Chen, Xi; Memik, Gokhan; Dinda, Peter A; Shy, Alex; Ozisikyilmaz, Berkin; Mallik, Arindam; Choudhary, Alok

    2014-04-22

    Systems and methods for controlling power consumption in a computer system. For each of a plurality of interactive applications, the method changes a frequency at which a processor of the computer system runs, receives an indication of user satisfaction, determines a relationship between the changed frequency and the user satisfaction of the interactive application, and stores the determined relationship information. The determined relationship can distinguish between different users and different interactive applications. A frequency may be selected from the discrete frequencies at which the processor of the computer system runs based on the determined relationship information for a particular user and a particular interactive application running on the processor of the computer system. The processor may be adapted to run at the selected frequency.

  6. Combustion Control System Design of Diesel Engine via ASPR based Output Feedback Control Strategy with a PFC

    NASA Astrophysics Data System (ADS)

    Mizumoto, Ikuro; Tsunematsu, Junpei; Fujii, Seiya

    2016-09-01

    In this paper, a design method of an output feedback control system with a simple feedforward input for a combustion model of diesel engine will be proposed based on the almost strictly positive real-ness (ASPR-ness) of the controlled system for a combustion control of diesel engines. A parallel feedforward compensator (PFC) design scheme which renders the resulting augmented controlled system ASPR will also be proposed in order to design a stable output feedback control system for the considered combustion model. The effectiveness of our proposed method will be confirmed through numerical simulations.

  7. Application of a Microcomputer-Based System to Control and Monitor Bacterial Growth

    PubMed Central

    Titus, Jeffrey A.; Luli, Gregory W.; Dekleva, Michael L.; Strohl, William R.

    1984-01-01

    A modular microcomputer-based system was developed to control and monitor various modes of bacterial growth. The control system was composed of an Apple II Plus microcomputer with 64-kilobyte random-access memory; a Cyborg ISAAC model 91A multichannel analog-to-digital and digital-to-analog converter; paired MRR-1 pH, pO2, and foam control units; and in-house-designed relay, servo control, and turbidimetry systems. To demonstrate the flexibility of the system, we grew bacteria under various computer-controlled and monitored modes of growth, including batch, turbidostat, and chemostat systems. The Apple-ISAAC system was programmed in Labsoft BASIC (extended Applesoft) with an average control program using ca. 6 to 8 kilobytes of memory and up to 30 kilobytes for datum arrays. This modular microcomputer-based control system was easily coupled to laboratory scale fermentors for a variety of fermentations. PMID:16346462

  8. Application of a microcomputer-based system to control and monitor bacterial growth.

    PubMed

    Titus, J A; Luli, G W; Dekleva, M L; Strohl, W R

    1984-02-01

    A modular microcomputer-based system was developed to control and monitor various modes of bacterial growth. The control system was composed of an Apple II Plus microcomputer with 64-kilobyte random-access memory; a Cyborg ISAAC model 91A multichannel analog-to-digital and digital-to-analog converter; paired MRR-1 pH, pO(2), and foam control units; and in-house-designed relay, servo control, and turbidimetry systems. To demonstrate the flexibility of the system, we grew bacteria under various computer-controlled and monitored modes of growth, including batch, turbidostat, and chemostat systems. The Apple-ISAAC system was programmed in Labsoft BASIC (extended Applesoft) with an average control program using ca. 6 to 8 kilobytes of memory and up to 30 kilobytes for datum arrays. This modular microcomputer-based control system was easily coupled to laboratory scale fermentors for a variety of fermentations. PMID:16346462

  9. A digital control system of brushless DC motor based on programmable logic device

    NASA Astrophysics Data System (ADS)

    Li, Jianke; Liu, Gang; Fang, Jiancheng

    2006-11-01

    A digital control system of brushless DC motor based on programmable Logic Device GAL16V8 and DSP is researched, and the principle and every element of the control system such as DSP2407,Logic handling segment, power driving circuit are analyzed. Compared with the software communication of BLDCM based on DSP, the control system has fast dynamic response, high reliability. The experimental result shows that the system has satisfied the spacecraft's demands on the BLDCM driving flywheel. In the end, the problem exited in the control system is analyzed on theory.

  10. Agent-based Cyber Control Strategy Design for Resilient Control Systems: Concepts, Architecture and Methodologies

    SciTech Connect

    Craig Rieger; Milos Manic; Miles McQueen

    2012-08-01

    The implementation of automated regulatory control has been around since the middle of the last century through analog means. It has allowed engineers to operate the plant more consistently by focusing on overall operations and settings instead of individual monitoring of local instruments (inside and outside of a control room). A similar approach is proposed for cyber security, where current border-protection designs have been inherited from information technology developments that lack consideration of the high-reliability, high consequence nature of industrial control systems. Instead of an independent development, however, an integrated approach is taken to develop a holistic understanding of performance. This performance takes shape inside a multiagent design, which provides a notional context to model highly decentralized and complex industrial process control systems, the nervous system of critical infrastructure. The resulting strategy will provide a framework for researching solutions to security and unrecognized interdependency concerns with industrial control systems.

  11. Application of PLC/PC based sootblower/waterlance control systems for optimizing boiler cleaning

    SciTech Connect

    Durrani, J.; Goode, W.C. Jr.

    1995-09-01

    This paper concerns retrofitting and upgrading existing sootblowers and waterlance control systems with a Programmable Logic Controller (PLC) and Personal Computer (PC)-based control system. The PLC is used for front end data collection and processing, and the PC is used for operator interface, sequence control and data acquisition for optimizing sootblower and waterlance performance. The versatility of the PLC/PC based control system provides a number of options to optimize boiler cleaning. Efficient and reliable boiler cleaning has been and continues to be a requirement due to the use of various types of coal required to meet various environmental requirements, while maintaining proper heat transfer. This paper will discuss a Boiler Cleaning Control System (BCCS) incorporated at the St. Clair Power Plant in April 1994. Provisions were made as needed for future interface to a Distributed Control System (DCS) and for boiler cleaning based on boiler performance, e.g., steam temperature.

  12. Observer-based tracking controller design for networked predictive control systems with uncertain Markov delays

    NASA Astrophysics Data System (ADS)

    Zhang, Hui; Shi, Yang; Wang, Junmin

    2013-10-01

    This paper is concerned with a tracking controller design problem for discrete-time networked predictive control systems. The control law used here is a combined state-feedback control and integral control. Since not all the states are available in practice, a local Luenberger observer is utilised to estimate the state vector. The measured output and estimated state vector are packed together and transmitted to the tracking controller via a communication channel with a limited capacity. Meanwhile, the control signal is also transmitted through a communication network.Network-induced delays on both links are considered for the signal transmission and modelled by Markov chains. Moreover, it is assumed that the elements in Markov transition matrices are subject to uncertainties. In order to fully compensate for network-induced delays, the controller generates a sequence of control signals which are dependent on each possible delay in the feedforward channel. By taking the augmentation twice, we obtain delay-free stochastic closed-loop systems and the controlled output is chosen as the tracking error. Sufficient conditions are provided for the energy-to-peak performance of the closed-loop systems. The feedback gains of the controller can be derived by solving a minimisation problem. Two examples are illustrated to demonstrate the effectiveness of the proposed design method.

  13. Learning control system design based on 2-D theory - An application to parallel link manipulator

    NASA Technical Reports Server (NTRS)

    Geng, Z.; Carroll, R. L.; Lee, J. D.; Haynes, L. H.

    1990-01-01

    An approach to iterative learning control system design based on two-dimensional system theory is presented. A two-dimensional model for the iterative learning control system which reveals the connections between learning control systems and two-dimensional system theory is established. A learning control algorithm is proposed, and the convergence of learning using this algorithm is guaranteed by two-dimensional stability. The learning algorithm is applied successfully to the trajectory tracking control problem for a parallel link robot manipulator. The excellent performance of this learning algorithm is demonstrated by the computer simulation results.

  14. Intelligent control of non-linear dynamical system based on the adaptive neurocontroller

    NASA Astrophysics Data System (ADS)

    Engel, E.; Kovalev, I. V.; Kobezhicov, V.

    2015-10-01

    This paper presents an adaptive neuro-controller for intelligent control of non-linear dynamical system. The formed as the fuzzy selective neural net the adaptive neuro-controller on the base of system's state, creates the effective control signal under random perturbations. The validity and advantages of the proposed adaptive neuro-controller are demonstrated by numerical simulations. The simulation results show that the proposed controller scheme achieves real-time control speed and the competitive performance, as compared to PID, fuzzy logic controllers.

  15. Design of a Performance-Adaptive PID Control System Based on Modeling Performance Assessment

    NASA Astrophysics Data System (ADS)

    Yamamoto, Toru

    In industrial processes represented by petroleum and refinery processes, it is necessary to establish the performance-driven control strategy in order to improve the productivity, which the control performance is firstly evaluated, and the controller is reconstructed. This paper describes a design scheme of performance-adaptive PID controllers which are based on the above control mechanism. According to the proposed control scheme, the system identification works corresponding to the result of modeling performance assessment, and PID parameters are computed using the newly estimated system parameters. In calculating the PID parameters, the desired control performance is considered. The behaviour of the proposed control scheme is numerically examined in some simulation examples.

  16. Implementation of EPICS based vacuum control system for variable energy cyclotron centre, Kolkata

    NASA Astrophysics Data System (ADS)

    Roy, Anindya; Bhole, R. B.; Nandy, Partha P.; Yadav, R. C.; Pal, Sarbajit; Roy, Amitava

    2015-03-01

    The vacuum system of the Room Temperature (K = 130) Cyclotron of Variable Energy Cyclotron Centre is comprised of vacuum systems of main machine and Beam Transport System. The vacuum control system is upgraded to a PLC based Automated system from the initial relay based Manual system. The supervisory control of the vacuum system is implemented in Experimental Physics and Industrial Control System (EPICS). An EPICS embedded ARM based vacuum gauge controller is developed to mitigate the requirement of vendor specific gauge controller for gauges and also for seamless integration of the gauge controllers with the control system. A set of MS-Windows ActiveX components with embedded EPICS Channel Access interface are developed to build operator interfaces with less complex programming and to incorporate typical Windows feature, e.g., user authentication, file handling, better fonts, colors, mouse actions etc. into the operator interfaces. The control parameters, monitoring parameters, and system interlocks of the system are archived in MySQL based EPICS MySQL Archiver developed indigenously. In this paper, we describe the architecture, the implementation details, and the performance of the system.

  17. Implementation of EPICS based vacuum control system for variable energy cyclotron centre, Kolkata

    SciTech Connect

    Roy, Anindya Bhole, R. B.; Nandy, Partha P.; Yadav, R. C.; Pal, Sarbajit; Roy, Amitava

    2015-03-15

    The vacuum system of the Room Temperature (K = 130) Cyclotron of Variable Energy Cyclotron Centre is comprised of vacuum systems of main machine and Beam Transport System. The vacuum control system is upgraded to a PLC based Automated system from the initial relay based Manual system. The supervisory control of the vacuum system is implemented in Experimental Physics and Industrial Control System (EPICS). An EPICS embedded ARM based vacuum gauge controller is developed to mitigate the requirement of vendor specific gauge controller for gauges and also for seamless integration of the gauge controllers with the control system. A set of MS-Windows ActiveX components with embedded EPICS Channel Access interface are developed to build operator interfaces with less complex programming and to incorporate typical Windows feature, e.g., user authentication, file handling, better fonts, colors, mouse actions etc. into the operator interfaces. The control parameters, monitoring parameters, and system interlocks of the system are archived in MySQL based EPICS MySQL Archiver developed indigenously. In this paper, we describe the architecture, the implementation details, and the performance of the system.

  18. Development of monitoring and control system for a mine main fan based on frequency converter

    NASA Astrophysics Data System (ADS)

    Zhang, Y. C.; Zhang, R. W.; Kong, X. Z.; Y Gong, J.; Chen, Q. G.

    2013-12-01

    In the process of mine exploitation, the requirement of air flow rate often changes. The procedure of traditional control mode of the fan is complex and it is hard to meet the worksite requirement for air. This system is based on Principal Computer (PC) monitoring system and high performance PLC control system. In this system, the frequency converter is adapted to adjust the fan speed and the air of worksite can be regulated steplessly. The function of the monitoring and control system contains on-line monitoring and centralized control. The system can monitor the parameters of fan in real-time, control the operation of frequency converter, as well as, control the fan and its accessory equipments. At the same time, the automation level of the system is highly, the field equipments can be monitored and controlled automatically. So, the system is an important safeguard for mine production.

  19. Safety Verification of a Fault Tolerant Reconfigurable Autonomous Goal-Based Robotic Control System

    NASA Technical Reports Server (NTRS)

    Braman, Julia M. B.; Murray, Richard M; Wagner, David A.

    2007-01-01

    Fault tolerance and safety verification of control systems are essential for the success of autonomous robotic systems. A control architecture called Mission Data System (MDS), developed at the Jet Propulsion Laboratory, takes a goal-based control approach. In this paper, a method for converting goal network control programs into linear hybrid systems is developed. The linear hybrid system can then be verified for safety in the presence of failures using existing symbolic model checkers. An example task is simulated in MDS and successfully verified using HyTech, a symbolic model checking software for linear hybrid systems.

  20. The Temperature Fuzzy Control System of Barleythe Malt Drying Based on Microcontroller

    NASA Astrophysics Data System (ADS)

    Gao, Xiaoyang; Bi, Yang; Zhang, Lili; Chen, Jingjing; Yun, Jianmin

    The control strategy of temperature and humidity in the beer barley malt drying chamber based on fuzzy logic control was implemented.Expounded in this paper was the selection of parameters for the structure of the regulatory device, as well as the essential design from control rules based on the existing experience. A temperature fuzzy controller was thus constructed using relevantfuzzy logic, and humidity control was achieved by relay, ensured the situation of the humidity to control the temperature. The temperature's fuzzy control and the humidity real-time control were all processed by single chip microcomputer with assembly program. The experimental results showed that the temperature control performance of this fuzzy regulatory system,especially in the ways of working stability and responding speed and so on,was better than normal used PID control. The cost of real-time system was inquite competitive position. It was demonstrated that the system have a promising prospect of extensive application.

  1. Investigation of neural-net based control strategies for improved power system dynamic performance

    SciTech Connect

    Sobajic, D.J.

    1995-12-31

    The ability to accurately predict the behavior of a dynamic system is of essential importance in monitoring and control of complex processes. In this regard recent advances in neural-net base system identification represent a significant step toward development and design of a new generation of control tools for increased system performance and reliability. The enabling functionality is the one of accurate representation of a model of a nonlinear and nonstationary dynamic system. This functionality provides valuable new opportunities including: (1) The ability to predict future system behavior on the basis of actual system observations, (2) On-line evaluation and display of system performance and design of early warning systems, and (3) Controller optimization for improved system performance. In this presentation, we discuss the issues involved in definition and design of learning control systems and their impact on power system control. Several numerical examples are provided for illustrative purpose.

  2. Nonholonomic mobile system control by combining EEG-based BCI with ANFIS.

    PubMed

    Yu, Weiwei; Feng, Huashan; Feng, Yangyang; Madani, Kurosh; Sabourin, Christophe

    2015-01-01

    Motor imagery EEG-based BCI has advantages in the assistance of human control of peripheral devices, such as the mobile robot or wheelchair, because the subject is not exposed to any stimulation and suffers no risk of fatigue. However, the intensive training necessary to recognize the numerous classes of data makes it hard to control these nonholonomic mobile systems accurately and effectively. This paper proposes a new approach which combines motor imagery EEG with the Adaptive Neural Fuzzy Inference System. This approach fuses the intelligence of humans based on motor imagery EEG with the precise capabilities of a mobile system based on ANFIS. This approach realizes a multi-level control, which makes the nonholonomic mobile system highly controllably without stopping or relying on sensor information. Also, because the ANFIS controller can be trained while performing the control task, control accuracy and efficiency is increased for the user. Experimental results of the nonholonomic mobile robot verify the effectiveness of this approach.

  3. A Modelica-based Model Library for Building Energy and Control Systems

    SciTech Connect

    Wetter, Michael

    2009-04-07

    This paper describes an open-source library with component models for building energy and control systems that is based on Modelica, an equation-based objectoriented language that is well positioned to become the standard for modeling of dynamic systems in various industrial sectors. The library is currently developed to support computational science and engineering for innovative building energy and control systems. Early applications will include controls design and analysis, rapid prototyping to support innovation of new building systems and the use of models during operation for controls, fault detection and diagnostics. This paper discusses the motivation for selecting an equation-based object-oriented language. It presents the architecture of the library and explains how base models can be used to rapidly implement new models. To demonstrate the capability of analyzing novel energy and control systems, the paper closes with an example where we compare the dynamic performance of a conventional hydronic heating system with thermostatic radiator valves to an innovative heating system. In the new system, instead of a centralized circulation pump, each of the 18 radiators has a pump whose speed is controlled using a room temperature feedback loop, and the temperature of the boiler is controlled based on the speed of the radiator pump. All flows are computed by solving for the pressure distribution in the piping network, and the controls include continuous and discrete time controls.

  4. Observer-based fault-tolerant control for a class of nonlinear networked control systems

    NASA Astrophysics Data System (ADS)

    Mahmoud, M. S.; Memon, A. M.; Shi, Peng

    2014-08-01

    This paper presents a fault-tolerant control (FTC) scheme for nonlinear systems which are connected in a networked control system. The nonlinear system is first transformed into two subsystems such that the unobservable part is affected by a fault and the observable part is unaffected. An observer is then designed which gives state estimates using a Luenberger observer and also estimates unknown parameter of the system; this helps in fault estimation. The FTC is applied in the presence of sampling due to the presence of a network in the loop. The controller gain is obtained using linear-quadratic regulator technique. The methodology is applied on a mechatronic system and the results show satisfactory performance.

  5. A microcomputer based data acquisition system and experiment controller

    NASA Technical Reports Server (NTRS)

    Ganz, M. W.

    1981-01-01

    A data acquisition system is described. The system monitors and records the signal strength of a radio beacon sent to Earth from a geosynchronous satellite. It acquires data from several devices such as a radar, a radiometer, and a rain gauge which monitor the meteorological conditions along the Earth space propagation path. The acquired data are stored in digital format on magnetic tape for analysis at the computer center. A detailed description of the design and operation of the system's various hardware components is given. Schematic diagrams, the theory of operation, and normal operating procedures are presented.

  6. The B-747 flight control system maintenance and reliability data base for cost effectiveness tradeoff studies

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Primary and automatic flight controls are combined for a total flight control reliability and maintenance cost data base using information from two previous reports and additional cost data gathered from a major airline. A comparison of the current B-747 flight control system effects on reliability and operating cost with that of a B-747 designed for an active control wing load alleviation system is provided.

  7. Microcontroller based Control System for Ultrasound NDT in Wood

    NASA Astrophysics Data System (ADS)

    Domingos, Fabiano C.; Maia, Joaquim M.; Maia, Ozana M. A.; Schneider, Fábio K.

    This work presents a microcontrolled system for transmission, acquisition and processing of ultrasound signals developed for the nondestructive testing (NDT) of wood samples. The developed system is able to generate high amplitude pulses (up to 500 Vpp) to excite an ultrasonic transducer and, after the ultrasound waves have propagated through the wood sample, the signal is received, amplified and then acquired using the microcontroller. The system was implemented with the TMDXDOCKH52C1 Concerto Experimenter Kit - F28M35H52C1 microcontroller (Texas Instruments) and a pair of ultrasound transducers (GE 67038, 50 kHz central frequency). Tests showed that the developed prototype meets the NDT application requirements. The data provided by the system can be used to determine the velocity, attenuation and other parameters of the ultrasound waves in wood samples for material characterization.

  8. Control system design method

    DOEpatents

    Wilson, David G.; Robinett, III, Rush D.

    2012-02-21

    A control system design method and concomitant control system comprising representing a physical apparatus to be controlled as a Hamiltonian system, determining elements of the Hamiltonian system representation which are power generators, power dissipators, and power storage devices, analyzing stability and performance of the Hamiltonian system based on the results of the determining step and determining necessary and sufficient conditions for stability of the Hamiltonian system, creating a stable control system based on the results of the analyzing step, and employing the resulting control system to control the physical apparatus.

  9. Optimal Redundancy Management in Reconfigurable Control Systems Based on Normalized Nonspecificity

    NASA Technical Reports Server (NTRS)

    Wu, N.Eva; Klir, George J.

    1998-01-01

    In this paper the notion of normalized nonspecificity is introduced. The nonspecifity measures the uncertainty of the estimated parameters that reflect impairment in a controlled system. Based on this notion, a quantity called a reconfiguration coverage is calculated. It represents the likelihood of success of a control reconfiguration action. This coverage links the overall system reliability to the achievable and required control, as well as diagnostic performance. The coverage, when calculated on-line, is used for managing the redundancy in the system.

  10. Application of plausible reasoning to AI-based control systems

    NASA Technical Reports Server (NTRS)

    Berenji, Hamid; Lum, Henry, Jr.

    1987-01-01

    Some current approaches to plausible reasoning in artificial intelligence are reviewed and discussed. Some of the most significant recent advances in plausible and approximate reasoning are examined. A synergism among the techniques of uncertainty management is advocated, and brief discussions on the certainty factor approach, probabilistic approach, Dempster-Shafer theory of evidence, possibility theory, linguistic variables, and fuzzy control are presented. Some extensions to these methods are described, and the applications of the methods are considered.

  11. An input-output based robust stabilization criterion for neural-network control of nonlinear systems.

    PubMed

    Fernández de Cañete, J; Barreiro, A; García-Cerezo, A; García-Moral, I

    2001-01-01

    A stabilization method based on the input-output conicity criterion is presented. Conventional learning algorithms are applied to adjust the controller dynamics, and robust stability of the closed-loop system is guaranteed by modifying the training patterns which yield unstable behavior. The methodology developed expands the class of nonlinear systems to be controlled using neural control schemes, so that the stabilization of a broad class of neural-network-based control systems, even with unknown dynamics, is assured. Straightforwardness in the application of this method is evident in contrast to the Lyapunov function approach. PMID:18249978

  12. Evolutionary game based control for biological systems with applications in drug delivery.

    PubMed

    Li, Xiaobo; Lenaghan, Scott C; Zhang, Mingjun

    2013-06-01

    Control engineering and analysis of biological systems have become increasingly important for systems and synthetic biology. Unfortunately, no widely accepted control framework is currently available for these systems, especially at the cell and molecular levels. This is partially due to the lack of appropriate mathematical models to describe the unique dynamics of biological systems, and the lack of implementation techniques, such as ultra-fast and ultra-small devices and corresponding control algorithms. This paper proposes a control framework for biological systems subject to dynamics that exhibit adaptive behavior under evolutionary pressures. The control framework was formulated based on evolutionary game based modeling, which integrates both the internal dynamics and the population dynamics. In the proposed control framework, the adaptive behavior was characterized as an internal dynamic, and the external environment was regarded as an external control input. The proposed open-interface control framework can be integrated with additional control algorithms for control of biological systems. To demonstrate the effectiveness of the proposed framework, an optimal control strategy was developed and validated for drug delivery using the pathogen Giardia lamblia as a test case. In principle, the proposed control framework can be applied to any biological system exhibiting adaptive behavior under evolutionary pressures.

  13. An autonomous observation and control system based on EPICS and RTS2 for Antarctic telescopes

    NASA Astrophysics Data System (ADS)

    Zhang, Guang-yu; Wang, Jian; Tang, Peng-yi; Jia, Ming-hao; Chen, Jie; Dong, Shu-cheng; Jiang, Fengxin; Wu, Wen-qing; Liu, Jia-jing; Zhang, Hong-fei

    2016-01-01

    For unattended telescopes in Antarctic, the remote operation, autonomous observation and control are essential. An EPICS-(Experimental Physics and Industrial Control System) and RTS2-(Remote Telescope System, 2nd Version) based autonomous observation and control system with remoted operation is introduced in this paper. EPICS is a set of open source software tools, libraries and applications developed collaboratively and used worldwide to create distributed soft real-time control systems for scientific instruments while RTS2 is an open source environment for control of a fully autonomous observatory. Using the advantage of EPICS and RTS2, respectively, a combined integrated software framework for autonomous observation and control is established that use RTS2 to fulfil the function of astronomical observation and use EPICS to fulfil the device control of telescope. A command and status interface for EPICS and RTS2 is designed to make the EPICS IOC (Input/Output Controller) components integrate to RTS2 directly. For the specification and requirement of control system of telescope in Antarctic, core components named Executor and Auto-focus for autonomous observation is designed and implemented with remote operation user interface based on browser-server mode. The whole system including the telescope is tested in Lijiang Observatory in Yunnan Province for practical observation to complete the autonomous observation and control, including telescope control, camera control, dome control, weather information acquisition with the local and remote operation.

  14. Design of an integral computer-based wheelchair controller/linear synchronous motor system.

    PubMed

    Kelly, G W; Ross, D A; Bass, R M; Davey, K R

    1986-06-01

    The purpose of this paper is to illustrate the advantages of designing computer-based motor controllers together with innovative motors, such that maximum controller/motor system benefits are obtained. Specifically, this paper describes how a computer-based controller/drive system for powered wheelchairs has been designed and is being built and tested. This type of integral controller/drive system has been possible to build into a wheelchair only with the advent of the microprocessor-based feedback motor controller. The type of motor chosen for this project was a linear synchronous motor (LSM), which is highly efficient (90%+) and could easily be made an integral part of a wheelchair wheel, providing a "no-moving-parts" drive system. However, an LSM cannot be variable-speed-controlled without knowledge of, and controlled adjustment to, the absolute rotor versus stator position at each point in time. Microprocessor-based feedback motor controllers make precise, efficient control of LSMs possible at a reasonable cost. In addition, this combination of controller and motor provides a very flexible wheelchair control/drive system that may be easily programmed to suit the needs and necessities of the wide variety of over 200,000 persons now using powered wheelchairs. PMID:3537184

  15. Position control of an electro-pneumatic system based on PWM technique and FLC.

    PubMed

    Najjari, Behrouz; Barakati, S Masoud; Mohammadi, Ali; Futohi, Muhammad J; Bostanian, Muhammad

    2014-03-01

    In this paper, modeling and PWM based control of an electro-pneumatic system, including the four 2-2 valves and a double acting cylinder are studied. Dynamic nonlinear behavior of the system, containing fast switching solenoid valves and a pneumatic cylinder, as well as electrical, magnetic, mechanical, and fluid subsystems are modeled. A DC-DC power converter is employed to improve solenoid valve performance and suppress system delay. Among different position control methods, a proportional integrator derivative (PID) controller and fuzzy logic controller (FLC) are evaluated. An experimental setup, using an AVR microcontroller is implemented. Simulation and experimental results verify the effectiveness of the proposed control strategies.

  16. Position control of an electro-pneumatic system based on PWM technique and FLC.

    PubMed

    Najjari, Behrouz; Barakati, S Masoud; Mohammadi, Ali; Futohi, Muhammad J; Bostanian, Muhammad

    2014-03-01

    In this paper, modeling and PWM based control of an electro-pneumatic system, including the four 2-2 valves and a double acting cylinder are studied. Dynamic nonlinear behavior of the system, containing fast switching solenoid valves and a pneumatic cylinder, as well as electrical, magnetic, mechanical, and fluid subsystems are modeled. A DC-DC power converter is employed to improve solenoid valve performance and suppress system delay. Among different position control methods, a proportional integrator derivative (PID) controller and fuzzy logic controller (FLC) are evaluated. An experimental setup, using an AVR microcontroller is implemented. Simulation and experimental results verify the effectiveness of the proposed control strategies. PMID:24485509

  17. Design and simulation of satellite attitude control system based on Simulink and VR

    NASA Astrophysics Data System (ADS)

    Zhang, Yang; Gan, Qingbo; Kang, Jingshu

    2016-01-01

    In order to research satellite attitude control system design and visual simulation, the simulation framework of satellite dynamics and attitude control using Simulink were established. The design of satellite earth-oriented control system based on quaternion feedback was completed. The 3D scene based on VR was created and models in the scene were driven by simulation data of Simulink. By coordinate transformation. successful observing the scene in inertial coordinate system, orbit coordinate system and body coordinate system. The result shows that application of simulation method of Simulink combined with VR in the design of satellite attitude control system field, has the advantages of high confidence level, hard real-time property, multi-perspective and multi-coordinate system observing the scene, and improves the comprehensibility and accuracy of the design.

  18. Preparation Model Based Control System For Hot Steel Strip Rolling Mill Stands

    NASA Astrophysics Data System (ADS)

    Bouazza, S. E.; Abbassi, H. A.; Moussaoui, A. K.

    2008-06-01

    As part of a research project on El-hadjar Hot Steel Rolling Mill Plant Annaba Algeria a new Model based control system is suggested to improve the performance of the hot strip rolling mill process. In this paper off-line model based controllers and a process simulator are described. The process models are based on the laws of physics. these models can predict the future behavior and the stability of the controlled process very reliably. The control scheme consists of a control algorithm. This Model based Control system is evaluated on a simulation model that represents accurately the dynamic of the process. Finally the usefulness to the Steel Industry of the suggested method is highlighted.

  19. Hot roller embossing system equipped with a temperature margin-based controller

    SciTech Connect

    Kim, Seyoung Son, Youngsu; Lee, Sunghee; Ham, Sangyong; Kim, Byungin

    2014-08-15

    A temperature control system was proposed for hot roller embossing. The roll surface was heated using induction coils and cooled with a circulating chilled water system. The temperature of the roll surface was precisely controlled by a temperature margin-based control algorithm that we developed. Implementation of the control system reduced deviations in the roll surface temperature to less than ±2 °C. The tight temperature control and the ability to rapidly increase and decrease the roll temperature will allow optimum operating parameters to be developed quickly. The temperature margin-based controller could also be used to optimize the time course of electrical power and shorten the cooling time by choosing an appropriate temperature margin, possibly for limited power consumption. The chiller-equipped heating roll with the proposed control algorithm is expected to decrease the time needed to determine the optimal embossing process.

  20. CONTROL SYSTEM

    DOEpatents

    Shannon, R.H.; Williamson, H.E.

    1962-10-30

    A boiling water type nuclear reactor power system having improved means of control is described. These means include provisions for either heating the coolant-moderator prior to entry into the reactor or shunting the coolantmoderator around the heating means in response to the demand from the heat engine. These provisions are in addition to means for withdrawing the control rods from the reactor. (AEC)

  1. Neural-network-observer-based optimal control for unknown nonlinear systems using adaptive dynamic programming

    NASA Astrophysics Data System (ADS)

    Liu, Derong; Huang, Yuzhu; Wang, Ding; Wei, Qinglai

    2013-09-01

    In this paper, an observer-based optimal control scheme is developed for unknown nonlinear systems using adaptive dynamic programming (ADP) algorithm. First, a neural-network (NN) observer is designed to estimate system states. Then, based on the observed states, a neuro-controller is constructed via ADP method to obtain the optimal control. In this design, two NN structures are used: a three-layer NN is used to construct the observer which can be applied to systems with higher degrees of nonlinearity and without a priori knowledge of system dynamics, and a critic NN is employed to approximate the value function. The optimal control law is computed using the critic NN and the observer NN. Uniform ultimate boundedness of the closed-loop system is guaranteed. The actor, critic, and observer structures are all implemented in real-time, continuously and simultaneously. Finally, simulation results are presented to demonstrate the effectiveness of the proposed control scheme.

  2. SpaceWire- Based Control System Architecture for the Lightweight Advanced Robotic Arm Demonstrator [LARAD

    NASA Astrophysics Data System (ADS)

    Rucinski, Marek; Coates, Adam; Montano, Giuseppe; Allouis, Elie; Jameux, David

    2015-09-01

    The Lightweight Advanced Robotic Arm Demonstrator (LARAD) is a state-of-the-art, two-meter long robotic arm for planetary surface exploration currently being developed by a UK consortium led by Airbus Defence and Space Ltd under contract to the UK Space Agency (CREST-2 programme). LARAD has a modular design, which allows for experimentation with different electronics and control software. The control system architecture includes the on-board computer, control software and firmware, and the communication infrastructure (e.g. data links, switches) connecting on-board computer(s), sensors, actuators and the end-effector. The purpose of the control system is to operate the arm according to pre-defined performance requirements, monitoring its behaviour in real-time and performing safing/recovery actions in case of faults. This paper reports on the results of a recent study about the feasibility of the development and integration of a novel control system architecture for LARAD fully based on the SpaceWire protocol. The current control system architecture is based on the combination of two communication protocols, Ethernet and CAN. The new SpaceWire-based control system will allow for improved monitoring and telecommanding performance thanks to higher communication data rate, allowing for the adoption of advanced control schemes, potentially based on multiple vision sensors, and for the handling of sophisticated end-effectors that require fine control, such as science payloads or robotic hands.

  3. [Research of controlling of smart home system based on P300 brain-computer interface].

    PubMed

    Wang, Jinjia; Yang, Chengjie

    2014-08-01

    Using electroencephalogram (EEG) signal to control external devices has always been the research focus in the field of brain-computer interface (BCI). This is especially significant for those disabilities who have lost capacity of movements. In this paper, the P300-based BCI and the microcontroller-based wireless radio frequency (RF) technology are utilized to design a smart home control system, which can be used to control household appliances, lighting system, and security devices directly. Experiment results showed that the system was simple, reliable and easy to be populirised.

  4. A knowledge-based system design/information tool for aircraft flight control systems

    NASA Technical Reports Server (NTRS)

    Mackall, Dale A.; Allen, James G.

    1989-01-01

    Research aircraft have become increasingly dependent on advanced control systems to accomplish program goals. These aircraft are integrating multiple disciplines to improve performance and satisfy research objectives. This integration is being accomplished through electronic control systems. Because of the number of systems involved and the variety of engineering disciplines, systems design methods and information management have become essential to program success. The primary objective of the system design/information tool for aircraft flight control system is to help transfer flight control system design knowledge to the flight test community. By providing all of the design information and covering multiple disciplines in a structured, graphical manner, flight control systems can more easily be understood by the test engineers. This will provide the engineers with the information needed to thoroughly ground test the system and thereby reduce the likelihood of serious design errors surfacing in flight. The secondary objective is to apply structured design techniques to all of the design domains. By using the techniques in the top level system design down through the detailed hardware and software designs, it is hoped that fewer design anomalies will result. The flight test experiences of three highly complex, integrated aircraft programs are reviewed: the X-29 forward-swept wing, the advanced fighter technology integration (AFTI) F-16, and the highly maneuverable aircraft technology (HiMAT) program. Significant operating anomalies and the design errors which cause them, are examined to help identify what functions a system design/information tool should provide to assist designers in avoiding errors.

  5. Development of an automatic subsea blowout preventer stack control system using PLC based SCADA.

    PubMed

    Cai, Baoping; Liu, Yonghong; Liu, Zengkai; Wang, Fei; Tian, Xiaojie; Zhang, Yanzhen

    2012-01-01

    An extremely reliable remote control system for subsea blowout preventer stack is developed based on the off-the-shelf triple modular redundancy system. To meet a high reliability requirement, various redundancy techniques such as controller redundancy, bus redundancy and network redundancy are used to design the system hardware architecture. The control logic, human-machine interface graphical design and redundant databases are developed by using the off-the-shelf software. A series of experiments were performed in laboratory to test the subsea blowout preventer stack control system. The results showed that the tested subsea blowout preventer functions could be executed successfully. For the faults of programmable logic controllers, discrete input groups and analog input groups, the control system could give correct alarms in the human-machine interface. PMID:21889767

  6. Functional Based Adaptive and Fuzzy Sliding Controller for Non-Autonomous Active Suspension System

    NASA Astrophysics Data System (ADS)

    Huang, Shiuh-Jer; Chen, Hung-Yi

    In this paper, an adaptive sliding controller is developed for controlling a vehicle active suspension system. The functional approximation technique is employed to substitute the unknown non-autonomous functions of the suspension system and release the model-based requirement of sliding mode control algorithm. In order to improve the control performance and reduce the implementation problem, a fuzzy strategy with online learning ability is added to compensate the functional approximation error. The update laws of the functional approximation coefficients and the fuzzy tuning parameters are derived from the Lyapunov theorem to guarantee the system stability. The proposed controller is implemented on a quarter-car hydraulic actuating active suspension system test-rig. The experimental results show that the proposed controller suppresses the oscillation amplitude of the suspension system effectively.

  7. Formation control and collision avoidance for multi-agent systems based on position estimation.

    PubMed

    Xia, Yuanqing; Na, Xitai; Sun, Zhongqi; Chen, Jing

    2016-03-01

    In this paper, formation control strategies based on position estimation for double-integrator systems are investigated. Firstly, an optimal control formation control strategy is derived based on the estimator. It is proven that the control inputs are able to drive the agents to the predefined formation and the controller is optimal even based on the estimation law if the estimator has converged to stable. Secondly, a consensus law based on the estimator is presented, which enables the agents converge to the formation in a cooperative manner. The stability can be guaranteed by proper parameters. Thirdly, extra control input for inter collision avoidance is added into the derived consensus control strategy, and efficacy analysis are provided in detail. Finally, the effectiveness of the strategies proposed are shown by simulation and experiment results. PMID:26786907

  8. Observer-based H∞ resilient control for a class of switched LPV systems and its application

    NASA Astrophysics Data System (ADS)

    Yang, Dong; Zhao, Jun

    2016-11-01

    This paper deals with the issue of observer-based H∞ resilient control for a class of switched linear parameter-varying (LPV) systems by utilising a multiple parameter-dependent Lyapunov functions method. First, attention is focused upon the design of a resilient observer, an observer-based resilient controller and a parameter and estimate state-dependent switching signal, which can stabilise and achieve the disturbance attenuation for the given systems. Then, a solvability condition of the H∞ resilient control problem is given in terms of matrix inequality for the switched LPV systems. This condition allows the H∞ resilient control problem for each individual subsystem to be unsolvable. The observer, controller, and switching signal are explicitly computed by solving linear matrix inequalities (LMIs). Finally, the effectiveness of the proposed control scheme is illustrated by its application to a turbofan engine, which can hardly be handled by the existing approaches.

  9. Predictive control strategies for wind turbine system based on permanent magnet synchronous generator.

    PubMed

    Maaoui-Ben Hassine, Ikram; Naouar, Mohamed Wissem; Mrabet-Bellaaj, Najiba

    2016-05-01

    In this paper, Model Predictive Control and Dead-beat predictive control strategies are proposed for the control of a PMSG based wind energy system. The proposed MPC considers the model of the converter-based system to forecast the possible future behavior of the controlled variables. It allows selecting the voltage vector to be applied that leads to a minimum error by minimizing a predefined cost function. The main features of the MPC are low current THD and robustness against parameters variations. The Dead-beat predictive control is based on the system model to compute the optimum voltage vector that ensures zero-steady state error. The optimum voltage vector is then applied through Space Vector Modulation (SVM) technique. The main advantages of the Dead-beat predictive control are low current THD and constant switching frequency. The proposed control techniques are presented and detailed for the control of back-to-back converter in a wind turbine system based on PMSG. Simulation results (under Matlab-Simulink software environment tool) and experimental results (under developed prototyping platform) are presented in order to show the performances of the considered control strategies.

  10. Predictive control strategies for wind turbine system based on permanent magnet synchronous generator.

    PubMed

    Maaoui-Ben Hassine, Ikram; Naouar, Mohamed Wissem; Mrabet-Bellaaj, Najiba

    2016-05-01

    In this paper, Model Predictive Control and Dead-beat predictive control strategies are proposed for the control of a PMSG based wind energy system. The proposed MPC considers the model of the converter-based system to forecast the possible future behavior of the controlled variables. It allows selecting the voltage vector to be applied that leads to a minimum error by minimizing a predefined cost function. The main features of the MPC are low current THD and robustness against parameters variations. The Dead-beat predictive control is based on the system model to compute the optimum voltage vector that ensures zero-steady state error. The optimum voltage vector is then applied through Space Vector Modulation (SVM) technique. The main advantages of the Dead-beat predictive control are low current THD and constant switching frequency. The proposed control techniques are presented and detailed for the control of back-to-back converter in a wind turbine system based on PMSG. Simulation results (under Matlab-Simulink software environment tool) and experimental results (under developed prototyping platform) are presented in order to show the performances of the considered control strategies. PMID:26725504

  11. Large space structure model reduction and control system design based upon actuator and sensor influence functions

    NASA Technical Reports Server (NTRS)

    Yam, Y.; Lang, J. H.; Johnson, T. L.; Shih, S.; Staelin, D. H.

    1983-01-01

    A model reduction procedure based on aggregation with respect to sensor and actuator influences rather than modes is presented for large systems of coupled second-order differential equations. Perturbation expressions which can predict the effects of spillover on both the aggregated and residual states are derived. These expressions lead to the development of control system design constraints which are sufficient to guarantee, to within the validity of the perturbations, that the residual states are not destabilized by control systems designed from the reduced model. A numerical example is provided to illustrate the application of the aggregation and control system design method.

  12. Integral-based event triggering controller design for stochastic LTI systems via convex optimisation

    NASA Astrophysics Data System (ADS)

    Mousavi, S. H.; Marquez, H. J.

    2016-07-01

    The presence of measurement noise in the event-based systems can lower system efficiency both in terms of data exchange rate and performance. In this paper, an integral-based event triggering control system is proposed for LTI systems with stochastic measurement noise. We show that the new mechanism is robust against noise and effectively reduces the flow of communication between plant and controller, and also improves output performance. Using a Lyapunov approach, stability in the mean square sense is proved. A simulated example illustrates the properties of our approach.

  13. Hierarchical Ada robot programming system (HARPS)- A complete and working telerobot control system based on the NASREM model

    NASA Technical Reports Server (NTRS)

    Leake, Stephen; Green, Tom; Cofer, Sue; Sauerwein, Tim

    1989-01-01

    HARPS is a telerobot control system that can perform some simple but useful tasks. This capability is demonstrated by performing the ORU exchange demonstration. HARPS is based on NASREM (NASA Standard Reference Model). All software is developed in Ada, and the project incorporates a number of different CASE (computer-aided software engineering) tools. NASREM was found to be a valid and useful model for building a telerobot control system. Its hierarchical and distributed structure creates a natural and logical flow for implementing large complex robust control systems. The ability of Ada to create and enforce abstraction enhanced the implementation of such control systems.

  14. A knowledge-based system design/information tool for aircraft flight control systems

    NASA Technical Reports Server (NTRS)

    Mackall, Dale A.; Allen, James G.

    1991-01-01

    Research aircraft have become increasingly dependent on advanced electronic control systems to accomplish program goals. These aircraft are integrating multiple disciplines to improve performance and satisfy research objective. This integration is being accomplished through electronic control systems. Systems design methods and information management have become essential to program success. The primary objective of the system design/information tool for aircraft flight control is to help transfer flight control system design knowledge to the flight test community. By providing all of the design information and covering multiple disciplines in a structured, graphical manner, flight control systems can more easily be understood by the test engineers. This will provide the engineers with the information needed to thoroughly ground test the system and thereby reduce the likelihood of serious design errors surfacing in flight. The secondary object is to apply structured design techniques to all of the design domains. By using the techniques in the top level system design down through the detailed hardware and software designs, it is hoped that fewer design anomalies will result. The flight test experiences are reviewed of three highly complex, integrated aircraft programs: the X-29 forward swept wing; the advanced fighter technology integration (AFTI) F-16; and the highly maneuverable aircraft technology (HiMAT) program. Significant operating technologies, and the design errors which cause them, is examined to help identify what functions a system design/informatin tool should provide to assist designers in avoiding errors.

  15. Design of a nonlinear backstepping control strategy of grid interconnected wind power system based PMSG

    NASA Astrophysics Data System (ADS)

    Errami, Y.; Obbadi, A.; Sahnoun, S.; Benhmida, M.; Ouassaid, M.; Maaroufi, M.

    2016-07-01

    This paper presents nonlinear backstepping control for Wind Power Generation System (WPGS) based Permanent Magnet Synchronous Generator (PMSG) and connected to utility grid. The block diagram of the WPGS with PMSG and the grid side back-to-back converter is established with the dq frame of axes. This control scheme emphasises the regulation of the dc-link voltage and the control of the power factor at changing wind speed. Besides, in the proposed control strategy of WPGS, Maximum Power Point Tracking (MPPT) technique and pitch control are provided. The stability of the regulators is assured by employing Lyapunov analysis. The proposed control strategy for the system has been validated by MATLAB simulations under varying wind velocity and the grid fault condition. In addition, a comparison of simulation results based on the proposed Backstepping strategy and conventional Vector Control is provided.

  16. Runge-Kutta model-based nonlinear observer for synchronization and control of chaotic systems.

    PubMed

    Beyhan, Selami

    2013-07-01

    This paper proposes a novel nonlinear gradient-based observer for synchronization and observer-based control of chaotic systems. The model is based on a Runge-Kutta model of the chaotic system where the evolution of the states or parameters is derived based on the error-square minimization. The stability and convergence conditions of observer and control methods are analyzed using a Lyapunov stability approach. In numerical simulations, the proposed observer and well-known sliding-mode observer are compared for the synchronization of a Lü chaotic system and observer-based stabilization of a Chen chaotic system. The noisy case for synchronization and parameter uncertainty case for stabilization are also considered for both observer-based methods.

  17. A robust PID controller based on imperialist competitive algorithm for load-frequency control of power systems.

    PubMed

    Shabani, Hamed; Vahidi, Behrooz; Ebrahimpour, Majid

    2013-01-01

    A new PID controller for resistant differential control against load disturbance is introduced that can be used for load frequency control (LFC) application. Parameters of the controller have been specified by using imperialist competitive algorithm (ICA). Load disturbance, which is due to continuous and rapid changes of small loads, is always a problem for load frequency control of power systems. This paper introduces a new method to overcome this problem that is based on filtering technique which eliminates the effect of this kind of disturbance. The object is frequency regulation in each area of the power system and decreasing of power transfer between control areas, so the parameters of the proposed controller have been specified in a wide range of load changes by means of ICA to achieve the best dynamic response of frequency. To evaluate the effectiveness of the proposed controller, a three-area power system is simulated in MATLAB/SIMULINK. Each area has different generation units, so utilizes controllers with different parameters. Finally a comparison between the proposed controller and two other prevalent PI controllers, optimized by GA and Neural Networks, has been done which represents advantages of this controller over others.

  18. Research on numerical control system based on S3C2410 and MCX314AL

    NASA Astrophysics Data System (ADS)

    Ren, Qiang; Jiang, Tingbiao

    2008-10-01

    With the rapid development of micro-computer technology, embedded system, CNC technology and integrated circuits, numerical control system with powerful functions can be realized by several high-speed CPU chips and RISC (Reduced Instruction Set Computing) chips which have small size and strong stability. In addition, the real-time operating system also makes the attainment of embedded system possible. Developing the NC system based on embedded technology can overcome some shortcomings of common PC-based CNC system, such as the waste of resources, low control precision, low frequency and low integration. This paper discusses a hardware platform of ENC (Embedded Numerical Control) system based on embedded processor chip ARM (Advanced RISC Machines)-S3C2410 and DSP (Digital Signal Processor)-MCX314AL and introduces the process of developing ENC system software. Finally write the MCX314AL's driver under the embedded Linux operating system. The embedded Linux operating system can deal with multitask well moreover satisfy the real-time and reliability of movement control. NC system has the advantages of best using resources and compact system with embedded technology. It provides a wealth of functions and superior performance with a lower cost. It can be sure that ENC is the direction of the future development.

  19. MonALISA: An agent based, dynamic service system to monitor, control and optimize distributed systems

    NASA Astrophysics Data System (ADS)

    Legrand, I.; Newman, H.; Voicu, R.; Cirstoiu, C.; Grigoras, C.; Dobre, C.; Muraru, A.; Costan, A.; Dediu, M.; Stratan, C.

    2009-12-01

    The MonALISA (Monitoring Agents in a Large Integrated Services Architecture) framework provides a set of distributed services for monitoring, control, management and global optimization for large scale distributed systems. It is based on an ensemble of autonomous, multi-threaded, agent-based subsystems which are registered as dynamic services. They can be automatically discovered and used by other services or clients. The distributed agents can collaborate and cooperate in performing a wide range of management, control and global optimization tasks using real time monitoring information. Program summaryProgram title: MonALISA Catalogue identifier: AEEZ_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEEZ_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Caltech License - free for all non-commercial activities No. of lines in distributed program, including test data, etc.: 147 802 No. of bytes in distributed program, including test data, etc.: 2 5913 689 Distribution format: tar.gz Programming language: Java, additional APIs available in Java, C, C++, Perl and python Computer: Computing Clusters, Network Devices, Storage Systems, Large scale data intensive applications Operating system: The MonALISA service is mainly used in Linux, the MonALISA client runs on all major platforms (Windows, Linux, Solaris, MacOS). Has the code been vectorized or parallelized?: It is a multithreaded application. It will efficiently use all the available processors. RAM: for the MonALISA service the minimum required memory is 64 MB; if the JVM is started allocating more memory this will be used for internal caching. The MonALISA client requires typically 256-512 MB of memory. Classification: 6.5 External routines: Requires Java: JRE or JDK to run. These external packages are used (they are included in the distribution): JINI, JFreeChart, PostgreSQL (optional). Nature of problem: To monitor and control

  20. On Decision-Making Among Multiple Rule-Bases in Fuzzy Control Systems

    NASA Technical Reports Server (NTRS)

    Tunstel, Edward; Jamshidi, Mo

    1997-01-01

    Intelligent control of complex multi-variable systems can be a challenge for single fuzzy rule-based controllers. This class of problems cam often be managed with less difficulty by distributing intelligent decision-making amongst a collection of rule-bases. Such an approach requires that a mechanism be chosen to ensure goal-oriented interaction between the multiple rule-bases. In this paper, a hierarchical rule-based approach is described. Decision-making mechanisms based on generalized concepts from single-rule-based fuzzy control are described. Finally, the effects of different aggregation operators on multi-rule-base decision-making are examined in a navigation control problem for mobile robots.

  1. Research and implementation of a large telescope control system based on wireless smart sensors

    NASA Astrophysics Data System (ADS)

    Shuai, Xiaoying; Zhang, Zhenchao; Ren, Changzhi; Zhu, Yongtian

    2008-07-01

    Telescope Control System (TCS) becomes more and more complexity, especially the large telescope control system of force actuators for deformed mirror and position actuators for modifiable degrees of mirrors. It is very difficult to connect thousands of sensors, actuators and controller with wired link. This paper presented a large telescope control system based on wireless smart sensor (WLTCS), connecting wireless sensors and controllers with wireless link, employing the TCP/IP protocol as communication protocol. Polling access can overcome contention and guarantee every sensor to communicate with controller in time; using intelligent control methods when some channels are interfered, multi-hop wireless paths can improve throughput and performance. The analysis and simulation indicate that WLTCS can greatly reduce complex of implementation and improve communication performance.

  2. A Comparison of Exposure Control Procedures in CAT Systems Based on Different Measurement Models for Testlets

    ERIC Educational Resources Information Center

    Boyd, Aimee M.; Dodd, Barbara; Fitzpatrick, Steven

    2013-01-01

    This study compared several exposure control procedures for CAT systems based on the three-parameter logistic testlet response theory model (Wang, Bradlow, & Wainer, 2002) and Masters' (1982) partial credit model when applied to a pool consisting entirely of testlets. The exposure control procedures studied were the modified within 0.10 logits…

  3. Passivity-based sliding mode control for a polytopic stochastic differential inclusion system.

    PubMed

    Liu, Leipo; Fu, Zhumu; Song, Xiaona

    2013-11-01

    Passivity-based sliding mode control for a polytopic stochastic differential inclusion (PSDI) system is considered. A control law is designed such that the reachability of sliding motion is guaranteed. Moreover, sufficient conditions for mean square asymptotic stability and passivity of sliding mode dynamics are obtained by linear matrix inequalities (LMIs). Finally, two examples are given to illustrate the effectiveness of the proposed method.

  4. Finite time control for MIMO nonlinear system based on higher-order sliding mode.

    PubMed

    Liu, Xiangjie; Han, Yaozhen

    2014-11-01

    Considering a class of MIMO uncertain nonlinear system, a novel finite time stable control algorithm is proposed based on higher-order sliding mode concept. The higher-order sliding mode control problem of MIMO nonlinear system is firstly transformed into finite time stability problem of multivariable system. Then continuous control law, which can guarantee finite time stabilization of nominal integral chain system, is employed. The second-order sliding mode is used to overcome the system uncertainties. High frequency chattering phenomenon of sliding mode is greatly weakened, and the arbitrarily fast convergence is reached. The finite time stability is proved based on the quadratic form Lyapunov function. Examples concerning the triple integral chain system with uncertainty and the hovercraft trajectory tracking are simulated respectively to verify the effectiveness and the robustness of the proposed algorithm. PMID:25277626

  5. Finite time control for MIMO nonlinear system based on higher-order sliding mode.

    PubMed

    Liu, Xiangjie; Han, Yaozhen

    2014-11-01

    Considering a class of MIMO uncertain nonlinear system, a novel finite time stable control algorithm is proposed based on higher-order sliding mode concept. The higher-order sliding mode control problem of MIMO nonlinear system is firstly transformed into finite time stability problem of multivariable system. Then continuous control law, which can guarantee finite time stabilization of nominal integral chain system, is employed. The second-order sliding mode is used to overcome the system uncertainties. High frequency chattering phenomenon of sliding mode is greatly weakened, and the arbitrarily fast convergence is reached. The finite time stability is proved based on the quadratic form Lyapunov function. Examples concerning the triple integral chain system with uncertainty and the hovercraft trajectory tracking are simulated respectively to verify the effectiveness and the robustness of the proposed algorithm.

  6. Experimental study of a self-powered and sensing MR-damper-based vibration control system

    NASA Astrophysics Data System (ADS)

    Sapiński, Bogdan

    2011-10-01

    The paper deals with a semi-active vibration control system based on a magnetorheological (MR) damper. The study outlines the model and the structure of the system, and describes its experimental investigation. The conceptual design of this system involves harvesting energy from structural vibrations using an energy extractor based on an electromagnetic transduction mechanism (Faraday's law). The system consists of an electromagnetic induction device (EMI) prototype and an MR damper of RD-1005 series manufactured by Lord Corporation. The energy extracted is applied to control the damping characteristics of the MR damper. The model of the system was used to prove that the proposed vibration control system is feasible. The system was realized in the semi-active control strategy with energy recovery and examined through experiments in the cases where the control coil of the MR damper was voltage-supplied directly from the EMI or voltage-supplied via the rectifier, or supplied with a current control system with two feedback loops. The external loop used the sky-hook algorithm whilst the internal loop used the algorithm switching the photorelay, at the output from the rectifier. Experimental results of the proposed vibration control system were compared with those obtained for the passive system (MR damper is off-state) and for the system with an external power source (conventional system) when the control coil of the MR damper was supplied by a DC power supply and analogue voltage amplifier or a DC power supply and a photorelay. It was demonstrated that the system is able to power-supply the MR damper and can adjust itself to structural vibrations. It was also found that, since the signal of induced voltage from the EMI agrees well with that of the relative velocity signal across the damper, the device can act as a 'velocity-sign' sensor.

  7. Development of a cost-effective PC-based motion control system

    SciTech Connect

    Hollar, D.L.

    1998-01-01

    A cost-effective PC-based motion control system was developed and evaluated for use on a laser welding system. The motion system is capable of X-Y simultaneous contouring and provides a rotary axis of motion also. The system motion paths can be specified in either Relative or Absolute motion. The PC controls all of the laser power supply and shutter I/O operations. All of the motion programming and operator interfacing is via the Windows {reg_sign}95 operating system.

  8. A refinement-based approach to developing software controllers for reactive systems

    SciTech Connect

    Winter, V.L.; Kapur, D.; Berg, R.S.

    1999-12-09

    The purpose of this paper is to demonstrate how transformation can be used to derive a high integrity implementation of a train controller from an algorithmic specification. The paper begins with a general discussion of high consequence systems (e.g., software systems) and describes how rewrite-based transformation systems can be used in the development of such systems. The authors then discuss how such transformations can be used to derive a high assurance controller for the Bay Area Rapid Transit (BART) system from an algorithmic specification.

  9. Knowledge-based adaptive neural control of drum level in a boiler system

    NASA Astrophysics Data System (ADS)

    Tripathi, Nishith; Tran, Michael; VanLandingham, Hugh

    1995-11-01

    A boiler system is an integral component of a thermal power plant, and control of the water level in the drum of the boiler system is a critical operational consideration. For the drum level control, a 3-element proportional-integral-derivative (PID) control is a popular conventional approach. This scheme works satisfactorily in the absence of any process disturbances. However, when there are significant process disturbances, the 3-element PID control scheme does not perform well because of lack of knowledge of proper controller gains to cope with such disturbances. Inevitably over time and use, PID controllers get detuned. Hence, there is good motivation to investigate alternatives to this control scheme. Multivariable control of drum boiler systems has been studied by many researchers. However, these approaches assume some process model equations (to a more or less extent) to design a controller. This paper presents a model-free approach in the sense that no plant equations are assumed. Only data is used to gain knowledge about the process, and the performance of the existing PID control scheme is observed. Based on this process knowledge, an intelligent control technique is developed, (artificial) neural network control (NNC). The technique proposed in this paper was tested on a process simulator. This paper shows that an intelligent control scheme such as NNC gives better performance in rejecting process disturbances when compared to 3-element PID control scheme.

  10. A voice coil motor based measuring force control system for tactile scanning profiler

    NASA Astrophysics Data System (ADS)

    Feng, Shengdong; Liu, Xiaojun; Chen, Liangzhou; Zhou, Liping; Lu, Wenlong

    2015-02-01

    In tactile scanning profiler, the measuring force would change in a wide range when it was used for profile measurement in a large range, which could possibly destroy the measured surface. To solve the problem, measuring force control system for tactile scanning profiler was needed. In the paper, a voice coil motor-based measuring force control system for tactile scanning profiler was designed. In the design, a low stiffness coefficient spring was used to provide contact force, while a voice coil motor (VCM) to balance the spring force so that the contact force could be kept for constant measuring force. A VCM was designed specially, and for active measuring force control, a precision current source circuit under the control of a DSP unit was designed to drive the VCM. The performance of voice coil motor based measuring force control system had been tested, and its good characteristics were verified.

  11. Thermal control systems for low-temperature heat rejection on a lunar base

    NASA Technical Reports Server (NTRS)

    Sridhar, K. R.; Gottmann, Matthias; Nanjundan, Ashok

    1993-01-01

    One of the important issues in the design of a lunar base is the thermal control system (TCS) used to reject low-temperature heat from the base. The TCS ensures that the base and the components inside are maintained within an acceptable temperature range. The temperature of the lunar surface peaks at 400 K during the 336-hour lunar day. Under these circumstances, direct dissipation of waste heat from the lunar base using passive radiators would be impractical. Thermal control systems based on thermal storage, shaded radiators, and heat pumps have been proposed. Based on proven technology, innovation, realistic complexity, reliability, and near-term applicability, a heat pump-based TCS was selected as a candidate for early missions. In this report, Rankine-cycle heat pumps and absorption heat pumps (ammonia water and lithium bromide-water) have been analyzed and optimized for a lunar base cooling load of 100 kW.

  12. A Framework for Context Sensitive Risk-Based Access Control in Medical Information Systems.

    PubMed

    Choi, Donghee; Kim, Dohoon; Park, Seog

    2015-01-01

    Since the access control environment has changed and the threat of insider information leakage has come to the fore, studies on risk-based access control models that decide access permissions dynamically have been conducted vigorously. Medical information systems should protect sensitive data such as medical information from insider threat and enable dynamic access control depending on the context such as life-threatening emergencies. In this paper, we suggest an approach and framework for context sensitive risk-based access control suitable for medical information systems. This approach categorizes context information, estimating and applying risk through context- and treatment-based permission profiling and specifications by expanding the eXtensible Access Control Markup Language (XACML) to apply risk. The proposed framework supports quick responses to medical situations and prevents unnecessary insider data access through dynamic access authorization decisions in accordance with the severity of the context and treatment. PMID:26075013

  13. A Framework for Context Sensitive Risk-Based Access Control in Medical Information Systems

    PubMed Central

    Choi, Donghee; Kim, Dohoon; Park, Seog

    2015-01-01

    Since the access control environment has changed and the threat of insider information leakage has come to the fore, studies on risk-based access control models that decide access permissions dynamically have been conducted vigorously. Medical information systems should protect sensitive data such as medical information from insider threat and enable dynamic access control depending on the context such as life-threatening emergencies. In this paper, we suggest an approach and framework for context sensitive risk-based access control suitable for medical information systems. This approach categorizes context information, estimating and applying risk through context- and treatment-based permission profiling and specifications by expanding the eXtensible Access Control Markup Language (XACML) to apply risk. The proposed framework supports quick responses to medical situations and prevents unnecessary insider data access through dynamic access authorization decisions in accordance with the severity of the context and treatment. PMID:26075013

  14. Designing RNA-based genetic control systems for efficient production from engineered metabolic pathways.

    PubMed

    Stevens, Jason T; Carothers, James M

    2015-02-20

    Engineered metabolic pathways can be augmented with dynamic regulatory controllers to increase production titers by minimizing toxicity and helping cells maintain homeostasis. We investigated the potential for dynamic RNA-based genetic control systems to increase production through simulation analysis of an engineered p-aminostyrene (p-AS) pathway in E. coli. To map the entire design space, we formulated 729 unique mechanistic models corresponding to all of the possible control topologies and mechanistic implementations in the system under study. Two thousand sampled simulations were performed for each of the 729 system designs to relate the potential effects of dynamic control to increases in p-AS production (total of 3 × 10(6) simulations). Our analysis indicates that dynamic control strategies employing aptazyme-regulated expression devices (aREDs) can yield >10-fold improvements over static control. We uncovered generalizable trends in successful control architectures and found that highly performing RNA-based control systems are experimentally tractable. Analyzing the metabolic control state space to predict optimal genetic control strategies promises to enhance the design of metabolic pathways. PMID:25314371

  15. Model-based Sliding Mode Controller of Anti-lock Braking System

    NASA Astrophysics Data System (ADS)

    Zheng, Lin; Luo, Yue-Gang; Kang, Jing; Shi, Zhan-Qun

    2016-05-01

    The anti-lock braking system (ABS) used in automobiles is used to prevent wheel from lockup and to maintain the steering ability and stability. The sliding mode controller is able to control nonlinear system steadily. In this research, a one-wheel dynamic model with ABS control is built up using model-based method. Using the sliding model controller, the simulation results by using Matlab/Simulink show qualified data compared with optimal slip rate. By using this method, the ABS brake efficiency is improved efficiently.

  16. Development of an Amine-based System for Combined Carbon Dioxide, Humidity, and Trace Contaminant Control

    NASA Technical Reports Server (NTRS)

    Nalette, Tim; Reiss, Julie; Filburn, Tom; Seery, Thomas; Smith, Fred; Perry, Jay

    2005-01-01

    A number of amine-based carbon dioxide (CO2) removal systems have been developed for atmosphere revitalization in closed loop life support systems. Most recently, Hamilton Sundstrand developed an amine-based sorbent, designated SA9T, possessing approximately 2-fold greater capacity compared to previous formulations. This new formulation has demonstrated applicability for controlling CO2 levels within vehicles and habitats as well as during extravehicular activity (EVA). System volume is competitive with existing technologies. Further enhancements in system performance can be realized by incorporating humidity and trace contaminant control functions within an amine-based atmosphere revitalization system. A 3-year effort to develop prototype hardware capable of removing CO2, H2O, and trace contaminants from a cabin atmosphere has been initiated. Progress pertaining to defining system requirements and identifying alternative amine formulations and substrates is presented.

  17. Cellular Decomposition Based Hybrid-Hierarchical Control Systems with Applications to Flight Management Systems

    NASA Technical Reports Server (NTRS)

    Caines, P. E.

    1999-01-01

    The work in this research project has been focused on the construction of a hierarchical hybrid control theory which is applicable to flight management systems. The motivation and underlying philosophical position for this work has been that the scale, inherent complexity and the large number of agents (aircraft) involved in an air traffic system imply that a hierarchical modelling and control methodology is required for its management and real time control. In the current work the complex discrete or continuous state space of a system with a small number of agents is aggregated in such a way that discrete (finite state machine or supervisory automaton) controlled dynamics are abstracted from the system's behaviour. High level control may then be either directly applied at this abstracted level, or, if this is in itself of significant complexity, further layers of abstractions may be created to produce a system with an acceptable degree of complexity at each level. By the nature of this construction, high level commands are necessarily realizable at lower levels in the system.

  18. A Model-based Framework for Risk Assessment in Human-Computer Controlled Systems

    NASA Technical Reports Server (NTRS)

    Hatanaka, Iwao

    2000-01-01

    The rapid growth of computer technology and innovation has played a significant role in the rise of computer automation of human tasks in modem production systems across all industries. Although the rationale for automation has been to eliminate "human error" or to relieve humans from manual repetitive tasks, various computer-related hazards and accidents have emerged as a direct result of increased system complexity attributed to computer automation. The risk assessment techniques utilized for electromechanical systems are not suitable for today's software-intensive systems or complex human-computer controlled systems. This thesis will propose a new systemic model-based framework for analyzing risk in safety-critical systems where both computers and humans are controlling safety-critical functions. A new systems accident model will be developed based upon modem systems theory and human cognitive processes to better characterize system accidents, the role of human operators, and the influence of software in its direct control of significant system functions. Better risk assessments will then be achievable through the application of this new framework to complex human-computer controlled systems.

  19. Consensus-Based Formation Control of a Class of Multi-Agent Systems

    NASA Technical Reports Server (NTRS)

    Joshi, Suresh; Gonzalez, Oscar R.

    2014-01-01

    This paper presents a consensus-based formation control scheme for autonomous multi-agent systems represented by double integrator dynamics. Assuming that the information graph topology consists of an undirected connected graph, a leader-based consensus-type control law is presented and shown to provide asymptotic formation stability when subjected to piecewise constant formation velocity commands. It is also shown that global asymptotic stability is preserved in the presence of (0, infinity)- sector monotonic non-decreasing actuator nonlinearities.

  20. Drive Control System for Pipeline Crawl Robot Based on CAN Bus

    NASA Astrophysics Data System (ADS)

    Chen, H. J.; Gao, B. T.; Zhang, X. H.; Deng2, Z. Q.

    2006-10-01

    Drive control system plays important roles in pipeline robot. In order to inspect the flaw and corrosion of seabed crude oil pipeline, an original mobile pipeline robot with crawler drive unit, power and monitor unit, central control unit, and ultrasonic wave inspection device is developed. The CAN bus connects these different function units and presents a reliable information channel. Considering the limited space, a compact hardware system is designed based on an ARM processor with two CAN controllers. With made-to-order CAN protocol for the crawl robot, an intelligent drive control system is developed. The implementation of the crawl robot demonstrates that the presented drive control scheme can meet the motion control requirements of the underwater pipeline crawl robot.

  1. Instrumentation and Control Needs for Reliable Operation of Lunar Base Surface Nuclear Power Systems

    NASA Technical Reports Server (NTRS)

    Turso, James; Chicatelli, Amy; Bajwa, Anupa

    2005-01-01

    As one of the near-term goals of the President's Vision for Space Exploration, establishment of a multi-person lunar base will require high-endurance power systems which are independent of the sun, and can operate without replenishment for several years. These requirements may be obtained using nuclear power systems specifically designed for use on the lunar surface. While it is envisioned that such a system will generally be supervised by humans, some of the evolutions required maybe semi or fully autonomous. The entire base complement for near-term missions may be less than 10 individuals, most or all of which may not be qualified nuclear plant operators and may be off-base for extended periods thus, the need for power system autonomous operation. Startup, shutdown, and load following operations will require the application of advanced control and health management strategies with an emphasis on robust, supervisory, coordinated control of, for example, the nuclear heat source, energy conversion plant (e.g., Brayton Energy Conversion units), and power management system. Autonomous operation implies that, in addition to being capable of automatic response to disturbance input or load changes, the system is also capable of assessing the status of the integrated plant, determining the risk associated with the possible actions, and making a decision as to the action that optimizes system performance while minimizing risk to the mission. Adapting the control to deviations from design conditions and degradation due to component failures will be essential to ensure base inhabitant safety and mission success. Intelligent decisions will have to be made to choose the right set of sensors to provide the data needed to do condition monitoring and fault detection and isolation because of liftoff weight and space limitations, it will not be possible to have an extensive set of instruments as used for earth-based systems. Advanced instrumentation and control technologies will be

  2. Application of a compound controller based on fuzzy control and support vector machine to ship's boiler-turbine coordinated control system

    NASA Astrophysics Data System (ADS)

    Liu, Sheng; Li, Yan-Yan

    2009-03-01

    Multivariables, strong coupling, nonlinearity, and large delays characterize the boiler-turbine coordinated control systems for ship power equipment. To better deal with these conditions, a compound control strategy based on a support vector machine (SVM) with inverse identification was proposed and applied to research simulating coordinated control systems. This method combines SVM inverse control and fuzzy control, taking advantage of the merits of SVM inverse controls which can be designed easily and have high reliability, and those of fuzzy controls, which respond rapidly and have good anti-jamming capability and robustness. It ensures the controller can be controlled with near instantaneous adjustments to maintain a steady state, even if the SVM is not trained well. The simulation results show that the control quality of this fuzzy-SVM compound control algorithm is high, with good performance in dynamic response speed, static stability, restraint of overshoot, and robustness.

  3. Neural Network based Control of SG based Standalone Generating System with Energy Storage for Power Quality Enhancement

    NASA Astrophysics Data System (ADS)

    Nayar, Priya; Singh, Bhim; Mishra, Sukumar

    2016-09-01

    An artificial intelligence based control algorithm is used in solving power quality problems of a diesel engine driven synchronous generator with automatic voltage regulator and governor based standalone system. A voltage source converter integrated with a battery energy storage system is employed to mitigate the power quality problems. An adaptive neural network based signed regressor control algorithm is used for the estimation of the fundamental component of load currents for control of a standalone system with load leveling as an integral feature. The developed model of the system performs accurately under varying load conditions and provides good dynamic response to the step changes in loads. The real time performance is achieved using MATLAB along with simulink/simpower system toolboxes and results adhere to an IEEE-519 standard for power quality enhancement.

  4. Further Investigation of Receding Horizion-Based Controllers and Neural Network-Based Systems

    NASA Technical Reports Server (NTRS)

    Kelkar, Atul G.; Haley, Pamela J. (Technical Monitor)

    2000-01-01

    This report provides a comprehensive summary of the research work performed over the entire duration of the co-operative research agreement between NASA Langley Research Center and Kansas State University. This summary briefly lists the findings and also suggests possible future directions for the continuation of the subject research in the area of Generalized Predictive Control (GPC) and Network Based Generalized Predictive Control (NGPC).

  5. Proximity-based access control for context-sensitive information provision in SOA-based systems

    NASA Astrophysics Data System (ADS)

    Rajappan, Gowri; Wang, Xiaofei; Grant, Robert; Paulini, Matthew

    2014-06-01

    Service Oriented Architecture (SOA) has enabled open-architecture integration of applications within an enterprise. For net-centric Command and Control (C2), this elucidates information sharing between applications and users, a critical requirement for mission success. The Information Technology (IT) access control schemes, which arbitrate who gets access to what information, do not yet have the contextual knowledge to dynamically allow this information sharing to happen dynamically. The access control might prevent legitimate users from accessing information relevant to the current mission context, since this context may be very different from the context for which the access privileges were configured. We evaluate a pair of data relevance measures - proximity and risk - and use these as the basis of dynamic access control. Proximity is a measure of the strength of connection between the user and the resource. However, proximity is not sufficient, since some data might have a negative impact, if leaked, which far outweighs importance to the subject's mission. For this, we use a risk measure to quantify the downside of data compromise. Given these contextual measures of proximity and risk, we investigate extending Attribute-Based Access Control (ABAC), which is used by the Department of Defense, and Role-Based Access Control (RBAC), which is widely used in the civilian market, so that these standards-based access control models are given contextual knowledge to enable dynamic information sharing. Furthermore, we consider the use of such a contextual access control scheme in a SOA-based environment, in particular for net-centric C2.

  6. NIRS-based neurofeedback learning systems for controlling activity of the prefrontal cortex.

    PubMed

    Sakatani, Kaoru; Takemoto, N; Tsujii, T; Yanagisawa, K; Tsunashima, H

    2013-01-01

    The aim of this study was to develop a NIRS-based neurofeedback system to modulate activity in the prefrontal cortex (PFC). We evaluated the effectiveness of the system in terms of separability of changes in oxy-Hb and its derivative. Training with neurofeedback resulted in higher separability than training without neurofeedback or no training, suggesting that the neurofeedback system could enhance self-control of PFC activity. Interestingly, the dorsolateral PFC exhibited enhanced activity and high separability after neurofeedback training. These observations suggest that the neurofeedback system might be useful for training subjects to regulate emotions by self-control of dorsolateral PFC activity.

  7. Pointing and figure control system for a space-based far-IR segmented telescope

    NASA Technical Reports Server (NTRS)

    Lau, Kenneth

    1993-01-01

    A pointing and figure control system for two space-based far-IR telescopes, the 10-20 m Large Deployable Reflector and the 3.6 m Submillimeter Intermediate Mission, is described. The figure maintenance control system is designed to counter the optical elements translational and rotational changes induced by long-term thermal drifts that the support structure may experience. The pointing system applies optical truss to telescope pointing; a laser metrology system is used to transfer pointing informaton from an external fine guidance sensor to the telescope optical boresight, defined by the primary mirror, secondary mirror, and focal plane assembly.

  8. System and method for air temperature control in an oxygen transport membrane based reactor

    DOEpatents

    Kelly, Sean M

    2016-09-27

    A system and method for air temperature control in an oxygen transport membrane based reactor is provided. The system and method involves introducing a specific quantity of cooling air or trim air in between stages in a multistage oxygen transport membrane based reactor or furnace to maintain generally consistent surface temperatures of the oxygen transport membrane elements and associated reactors. The associated reactors may include reforming reactors, boilers or process gas heaters.

  9. Nonholonomic mobile system control by combining EEG-based BCI with ANFIS.

    PubMed

    Yu, Weiwei; Feng, Huashan; Feng, Yangyang; Madani, Kurosh; Sabourin, Christophe

    2015-01-01

    Motor imagery EEG-based BCI has advantages in the assistance of human control of peripheral devices, such as the mobile robot or wheelchair, because the subject is not exposed to any stimulation and suffers no risk of fatigue. However, the intensive training necessary to recognize the numerous classes of data makes it hard to control these nonholonomic mobile systems accurately and effectively. This paper proposes a new approach which combines motor imagery EEG with the Adaptive Neural Fuzzy Inference System. This approach fuses the intelligence of humans based on motor imagery EEG with the precise capabilities of a mobile system based on ANFIS. This approach realizes a multi-level control, which makes the nonholonomic mobile system highly controllably without stopping or relying on sensor information. Also, because the ANFIS controller can be trained while performing the control task, control accuracy and efficiency is increased for the user. Experimental results of the nonholonomic mobile robot verify the effectiveness of this approach. PMID:26405870

  10. Noise filtering algorithm for the MFTF-B computer based control system

    SciTech Connect

    Minor, E.G.

    1983-11-30

    An algorithm to reduce the message traffic in the MFTF-B computer based control system is described. The algorithm filters analog inputs to the control system. Its purpose is to distinguish between changes in the inputs due to noise and changes due to significant variations in the quantity being monitored. Noise is rejected while significant changes are reported to the control system data base, thus keeping the data base updated with a minimum number of messages. The algorithm is memory efficient, requiring only four bytes of storage per analog channel, and computationally simple, requiring only subtraction and comparison. Quantitative analysis of the algorithm is presented for the case of additive Gaussian noise. It is shown that the algorithm is stable and tends toward the mean value of the monitored variable over a wide variety of additive noise distributions.

  11. Implementing supercritical water oxidation technology in a lunar base environmental control/life support system

    NASA Technical Reports Server (NTRS)

    Meyer Sedej, M.

    1985-01-01

    A supercritical water oxidation system (SCWOS) offers several advantages for a lunar base environmental control/life support system (ECLSS) compared to an ECLSS based on Space Station technology. In supercritically heated water (630 K, 250 atm) organic materials mix freely with oxygen and undergo complete combustion. Inorganic salts lose solubility and precipitate out. Implementation of SCWOS can make an ECLSS more efficient and reliable by elimination of several subsystems and by reduction in potential losses of life support consumables. More complete closure of the total system reduces resupply requirements from the earth, a crucial cost item in maintaining a lunar base.

  12. Integrated flight/propulsion control system design based on a centralized approach

    NASA Technical Reports Server (NTRS)

    Garg, Sanjay; Mattern, Duane L.; Bullard, Randy E.

    1989-01-01

    An integrated flight/propulsion control system design is presented for the piloted longitudinal landing task with a modern, statically unstable, fighter aircraft. A centralized compensator based on the Linear Quadratic Gaussian/Loop Transfer Recovery methodology is first obtained to satisfy the feedback loop performance and robustness specificiations. This high-order centralized compensator is then partitioned into airframe and engine sub-controllers based on modal controllability/observability for the compensator modes. The order of the sub-controllers is then reduced using internally-balanced realization techniques and the sub-controllers are simplified by neglecting the insignificant feedbacks. These sub-controllers have the advantage that they can be implemented as separate controllers on the airframe and the engine while still retaining the important performance and stability characteristics of the full-order centralized compensator. Command prefilters are then designed for the closed-loop system with the simplified sub-controllers to obtain the desired system response to airframe and engine command inputs, and the overall system performance evaluation results are presented.

  13. Configuration maintaining control of three-body ring tethered system based on thrust compensation

    NASA Astrophysics Data System (ADS)

    Huang, Panfeng; Liu, Binbin; Zhang, Fan

    2016-06-01

    Space multi-tethered systems have shown broad prospects in remote observation missions. This paper mainly focuses on the dynamics and configuration maintaining control of space spinning three-body ring tethered system for such mission. Firstly, we establish the spinning dynamic model of the three-body ring tethered system considering the elasticity of the tether using Newton-Euler method, and then validate the suitability of this model by numerical simulation. Subsequently, LP (Likins-Pringle) initial equilibrium conditions for the tethered system are derived based on rigid body's equilibrium theory. Simulation results show that tether slack, snapping and interaction between the tethers exist in the three-body ring system, and its' configuration can not be maintained without control. Finally, a control strategy based on thrust compensation, namely thrust to simulate tether compression under LP initial equilibrium conditions is designed to solve the configuration maintaining control problem. Control effects are verified by numerical simulation compared with uncontrolled situation. Simulation results show that the configuration of the three-body ring tethered system could maintain under this active control strategy.

  14. Centralized PI control for high dimensional multivariable systems based on equivalent transfer function.

    PubMed

    Luan, Xiaoli; Chen, Qiang; Liu, Fei

    2014-09-01

    This article presents a new scheme to design full matrix controller for high dimensional multivariable processes based on equivalent transfer function (ETF). Differing from existing ETF method, the proposed ETF is derived directly by exploiting the relationship between the equivalent closed-loop transfer function and the inverse of open-loop transfer function. Based on the obtained ETF, the full matrix controller is designed utilizing the existing PI tuning rules. The new proposed ETF model can more accurately represent the original processes. Furthermore, the full matrix centralized controller design method proposed in this paper is applicable to high dimensional multivariable systems with satisfactory performance. Comparison with other multivariable controllers shows that the designed ETF based controller is superior with respect to design-complexity and obtained performance.

  15. Smart greenhouse fuzzy logic based control system enhanced with wireless data monitoring.

    PubMed

    Azaza, M; Tanougast, C; Fabrizio, E; Mami, A

    2016-03-01

    Greenhouse climate control is complicated procedure since the number of variables involved on it and which are dependent on each other. This paper presents a contribution to integrate greenhouse inside climate key's parameters, leading to promote a comfortable micro-climate for the plants growth while saving energy and water resources. A smart fuzzy logic based control system was introduced and improved through specific measure to the temperature and humidity correlation. As well, the system control was enhanced with wireless data monitoring platform for data routing and logging, which provides real time data access. The proposed control system was experimentally validated. The efficiency of the system was evaluated showing important energy and water saving. PMID:26749556

  16. Smart greenhouse fuzzy logic based control system enhanced with wireless data monitoring.

    PubMed

    Azaza, M; Tanougast, C; Fabrizio, E; Mami, A

    2016-03-01

    Greenhouse climate control is complicated procedure since the number of variables involved on it and which are dependent on each other. This paper presents a contribution to integrate greenhouse inside climate key's parameters, leading to promote a comfortable micro-climate for the plants growth while saving energy and water resources. A smart fuzzy logic based control system was introduced and improved through specific measure to the temperature and humidity correlation. As well, the system control was enhanced with wireless data monitoring platform for data routing and logging, which provides real time data access. The proposed control system was experimentally validated. The efficiency of the system was evaluated showing important energy and water saving.

  17. FPGA-based Elman neural network control system for linear ultrasonic motor.

    PubMed

    Lin, Faa-Jeng; Hung, Ying-Chih

    2009-01-01

    A field-programmable gate array (FPGA)-based Elman neural network (ENN) control system is proposed to control the mover position of a linear ultrasonic motor (LUSM) in this study. First, the structure and operating principle of the LUSM are introduced. Because the dynamic characteristics and motor parameters of the LUSM are nonlinear and time-varying, an ENN control system is designed to achieve precision position control. The network structure and online learning algorithm using delta adaptation law of the ENN are described in detail. Then, a piecewise continuous function is adopted to replace the sigmoid function in the hidden layer of the ENN to facilitate hardware implementation. In addition, an FPGA chip is adopted to implement the developed control algorithm for possible low-cost and high-performance industrial applications. The effectiveness of the proposed control scheme is verified by some experimental results.

  18. Back propagation neural network based control for the heating system of a polysilicon reduction furnace.

    PubMed

    Cheng, Yuhua; Chen, Kai; Bai, Libing; Dai, Meizhi

    2013-12-01

    In this paper, the Back Propagation (BP) neural network based control strategy is proposed for the heating system of a polysilicon reduction furnace. It is applied to obtain the control signal I(d), which is used to adjust the heating power through operations of the silicon core temperature, furnace temperature, silicon core voltage, and resistance of the current control cycle. With the control signal I(d) the polycrystalline silicon can be heated from room temperature to the required temperature smoothly and steadily. The proposed BP network applied in this paper can obtain the accurate control signal I(d) and achieve the precise control purpose. This paper presents the principle of the BP network and demonstrates the effectiveness of the BP network in the heating system of a polysilicon reduction furnace by combining the simulation analysis with experimental results.

  19. The upgrade of an educational observatory control system with a PLC-based architecture

    NASA Astrophysics Data System (ADS)

    Baldini, V.; Cirami, R.; Coretti, I.; Di Marcantonio, P.; Galeotta, S.; Iafrate, G.; Mannetta, M.; Santin, P.

    2014-07-01

    A Celestron C14 telescope equipped with a robotic Paramount ME equatorial mount is being used for public outreach at the Basovizza site of the INAF-Astronomical Observatory of Trieste. Although the telescope could be fully remotely controlled, the control of the instrumentations and the movement of the main motor of the dome requires the physical presence of an operator. To overcome this limitation the existing control system has been upgraded using a Beckhoff PLC to allow the remote control of the whole instrumentation, including the management of the newly installed weather sensor and the access to the telescope area. Exploiting the decentralization features typical of a PLC based solution, the PLC modules are placed in two different racks, according to the function to be controlled. A web interface is used for the communication between the user and the instrumentation. The architecture of this control system will be presented in detail in this paper.

  20. Use of model-based qualitative icons and adaptive windows in workstations for supervisory control systems

    NASA Technical Reports Server (NTRS)

    Mitchell, Christine M.; Saisi, Donna L.

    1987-01-01

    The effectiveness of an operator interface using qualitative icons and dynamic windows designed and controlled by means of an operator function model is demonstrated, and the simulation system, the Georgia Tech-Multisatellite Operations Control Center, is described. Qualitative icons are used to integrate low-level quantitative data into high-level qualitative error detection mechanisms, and window technology is used for the simultaneous display of multiple data sources that reflect different aspects of the system state. Based on eleven experimental measures, the workstation incorporating the model-based qualitative icons and dynamic operator function window sets was found to perform better than the conventional workstation.

  1. Control system and laser-based sensor design of an automonous vehicle for industrial environments

    NASA Astrophysics Data System (ADS)

    Sanchiz, Jose M.; Badenas, Jorge; Pla, Filiberto

    2004-09-01

    This work presents an approach to the sensorial device and control system of an autonomous vehicle intended for navigating and performing precise load/unload tasks in industrial environments. The control system is able to perform turns, line following, and arbitrary curve following specified as splines. It is based on a multivariable design using the technique of pole placement in state space. The control system uses results from parameter estimation modules to adapt to the changing responses of traction motors when loaded or unloaded, such estimators are Kalman filters that recover the vehicle motion parameters from measurements performed by the positioning sensor. Several steering configurations are possible since the control system provides a radius of turn as output. So differential drive, tricycle drive or Ackerman steering can be done by transforming this radius in motor orders, depending on the geometry of the vehicle. The only sensor the system relies on is a laser-based local positioning system consisting of a rotating laser and retro-reflectors. Robust algorithms for signal analysis and position/orientation estimation have been developed. The sensor is able to detect reflectors 25 meters away in daylight or in dusty industrial environments using a low-cost 1 mW laser. The system has been tested on two mobile bases, using differential drive and tricycle drive.

  2. Smart monitoring system based on adaptive current control for superconducting cable test

    SciTech Connect

    Arpaia, Pasquale; Ballarino, Amalia; Montenero, Giuseppe; Daponte, Vincenzo; Svelto, Cesare

    2014-12-15

    A smart monitoring system for superconducting cable test is proposed with an adaptive current control of a superconducting transformer secondary. The design, based on Fuzzy Gain Scheduling, allows the controller parameters to adapt continuously, and finely, to the working variations arising from transformer nonlinear dynamics. The control system is integrated in a fully digital control loop, with all the related benefits, i.e., high noise rejection, ease of implementation/modification, and so on. In particular, an accurate model of the system, controlled by a Fuzzy Gain Scheduler of the superconducting transformer, was achieved by an experimental campaign through the working domain at several current ramp rates. The model performance was characterized by simulation, under all the main operating conditions, in order to guide the controller design. Finally, the proposed monitoring system was experimentally validated at European Organization for Nuclear Research (CERN) in comparison to the state-of-the-art control system [P. Arpaia, L. Bottura, G. Montenero, and S. Le Naour, “Performance improvement of a measurement station for superconducting cable test,” Rev. Sci. Instrum.83, 095111 (2012)] of the Facility for the Research on Superconducting Cables, achieving a significant performance improvement: a reduction in the system overshoot by 50%, with a related attenuation of the corresponding dynamic residual error (both absolute and RMS) up to 52%.

  3. Smart monitoring system based on adaptive current control for superconducting cable test

    NASA Astrophysics Data System (ADS)

    Arpaia, Pasquale; Ballarino, Amalia; Daponte, Vincenzo; Montenero, Giuseppe; Svelto, Cesare

    2014-12-01

    A smart monitoring system for superconducting cable test is proposed with an adaptive current control of a superconducting transformer secondary. The design, based on Fuzzy Gain Scheduling, allows the controller parameters to adapt continuously, and finely, to the working variations arising from transformer nonlinear dynamics. The control system is integrated in a fully digital control loop, with all the related benefits, i.e., high noise rejection, ease of implementation/modification, and so on. In particular, an accurate model of the system, controlled by a Fuzzy Gain Scheduler of the superconducting transformer, was achieved by an experimental campaign through the working domain at several current ramp rates. The model performance was characterized by simulation, under all the main operating conditions, in order to guide the controller design. Finally, the proposed monitoring system was experimentally validated at European Organization for Nuclear Research (CERN) in comparison to the state-of-the-art control system [P. Arpaia, L. Bottura, G. Montenero, and S. Le Naour, "Performance improvement of a measurement station for superconducting cable test," Rev. Sci. Instrum. 83, 095111 (2012)] of the Facility for the Research on Superconducting Cables, achieving a significant performance improvement: a reduction in the system overshoot by 50%, with a related attenuation of the corresponding dynamic residual error (both absolute and RMS) up to 52%.

  4. Novel Control for Voltage Boosted Matrix Converter based Wind Energy Conversion System with Practicality

    NASA Astrophysics Data System (ADS)

    Kumar, Vinod; Joshi, Raghuveer Raj; Yadav, Dinesh Kumar; Garg, Rahul Kumar

    2016-06-01

    This paper presents the implementation and investigation of novel voltage boosted matrix converter (MC) based permanent magnet wind energy conversion system (WECS). In this paper, on-line tuned adaptive fuzzy control algorithm cooperated with reversed MC is proposed to yield maximum energy. The control system is implemented on a dSPACE DS1104 real time board. Feasibility of the proposed system has been experimentally verified using a laboratory 1.2 kW prototype of WECS under steady-state and dynamic conditions.

  5. Data-based controllability analysis of discrete-time linear time-delay systems

    NASA Astrophysics Data System (ADS)

    Liu, Yang; Chen, Hong-Wei; Lu, Jian-Quan

    2014-11-01

    In this paper, a data-based method is used to analyse the controllability of discrete-time linear time-delay systems. By this method, one can directly construct a controllability matrix using the measured state data without identifying system parameters. Hence, one can save time in practice and avoid corresponding identification errors. Moreover, its calculation precision is higher than some other traditional approaches, which need to identify unknown parameters. Our methods are feasible to the study of characteristics of deterministic systems. A numerical example is given to show the advantage of our results.

  6. Knowledge-Based Motion Control of AN Intelligent Mobile Autonomous System

    NASA Astrophysics Data System (ADS)

    Isik, Can

    An Intelligent Mobile Autonomous System (IMAS), which is equipped with vision and low level sensors to cope with unknown obstacles, is modeled as a hierarchy of path planning and motion control. This dissertation concentrates on the lower level of this hierarchy (Pilot) with a knowledge-based controller. The basis of a theory of knowledge-based controllers is established, using the example of the Pilot level motion control of IMAS. In this context, the knowledge-based controller with a linguistic world concept is shown to be adequate for the minimum time control of an autonomous mobile robot motion. The Pilot level motion control of IMAS is approached in the framework of production systems. The three major components of the knowledge-based control that are included here are the hierarchies of the database, the rule base and the rule evaluator. The database, which is the representation of the state of the world, is organized as a semantic network, using a concept of minimal admissible vocabulary. The hierarchy of rule base is derived from the analytical formulation of minimum-time control of IMAS motion. The procedure introduced for rule derivation, which is called analytical model verbalization, utilizes the concept of causalities to describe the system behavior. A realistic analytical system model is developed and the minimum-time motion control in an obstacle strewn environment is decomposed to a hierarchy of motion planning and control. The conditions for the validity of the hierarchical problem decomposition are established, and the consistency of operation is maintained by detecting the long term conflicting decisions of the levels of the hierarchy. The imprecision in the world description is modeled using the theory of fuzzy sets. The method developed for the choice of the rule that prescribes the minimum-time motion control among the redundant set of applicable rules is explained and the usage of fuzzy set operators is justified. Also included in the

  7. Power Management Based Current Control Technique for Photovoltaic-Battery Assisted Wind-Hydro Hybrid System

    NASA Astrophysics Data System (ADS)

    Ram Prabhakar, J.; Ragavan, K.

    2013-07-01

    This article proposes new power management based current control strategy for integrated wind-solar-hydro system equipped with battery storage mechanism. In this control technique, an indirect estimation of load current is done, through energy balance model, DC-link voltage control and droop control. This system features simpler energy management strategy and necessitates few power electronic converters, thereby minimizing the cost of the system. The generation-demand (G-D) management diagram is formulated based on the stochastic weather conditions and demand, which would likely moderate the gap between both. The features of management strategy deploying energy balance model include (1) regulating DC-link voltage within specified tolerances, (2) isolated operation without relying on external electric power transmission network, (3) indirect current control of hydro turbine driven induction generator and (4) seamless transition between grid-connected and off-grid operation modes. Furthermore, structuring of the hybrid system with appropriate selection of control variables enables power sharing among each energy conversion systems and battery storage mechanism. By addressing these intricacies, it is viable to regulate the frequency and voltage of the remote network at load end. The performance of the proposed composite scheme is demonstrated through time-domain simulation in MATLAB/Simulink environment.

  8. Coordination between control and knowledge based systems for autonomous vehicle guidance

    SciTech Connect

    Harmon, S.Y.

    1983-01-01

    A technique for coordination between control and knowledge based components of an autonomous mobile robot guidance system is discussed. This technique models the interaction process as multiple message passing tasks. A protocol with which to structure the messages has been developed. This protocol builds upon an available transport layer. The synchronization between tasks for real time control and slower knowledge based tasks is achieved by having the knowledge based tasks always work in anticipation of events to come. The implementation of this technique in the form of an autonomous mobile ground robot is used for illustration. Various elements of this robot's hardware and software architecture are discussed.

  9. A Control System for Tobacco Shred Production Line Based on Industrial Ethernet

    NASA Astrophysics Data System (ADS)

    Zhang, Li; Zheng, Guang; Zhang, Xinfeng; Liu, Lei; Xi, Lei

    The Industrial Ethernet based on IP realizes interconnection of industrial network and information network, and it is the most potential technology in the new industrial net products. In this paper, the defects of the original control system for tobacco shred production line are analyzed, and the new design plan of control system based on EtherNet/IP is presented. The control net adopts redundant 1000M fiber optic ring network that consists of six managed Industrial Ethernet Switches, and they are distributed to the central control room, leaf processing line, shred processing line, mixed stem shred processing line, online mositure regain processing line and cut tobacco dryer control cabinet. The switch in the central control room works in the pattern of redundancy management, which can switch the link in the event of the failure in link of ring net, the recovery time of link line is less than 500ms, and each main PLC of control section has dual Network Adapters. The plan has been applied for reform of 5000kg/h Tobacco Primary Processing Line in Nanyang Cigarette Factory of China Tobacco Henan Industrial Corporation, and the configurable software and Industry Ethernet network which has been used promots the capability of automatic control system fundamentally, showing much better transmission efficiency and reliability, realizing the goal of high cost performance and making equipment's ability of handling grow fast.

  10. Design and initial validation of a wireless control system based on WSN

    NASA Astrophysics Data System (ADS)

    Yu, Yan; Li, Luyu; Li, Peng; Wang, Xu; Liu, Hang; Ou, Jinping

    2013-04-01

    At present, cantilever structure used widely in civil structures will generate continuous vibration by external force due to their low damping characteristic, which leads to a serious impact on the working performance and service time. Therefore, it is very important to control the vibration of these structures. The active vibration control is the primary means of controlling the vibration with high precision and strong adaptive ability. Nowadays, there are many researches using piezoelectric materials in the structural vibration control. Piezoelectric materials are cheap, reliable and they can provide braking and sensing method harmless to the structure, therefore they have broad usage. They are used for structural vibration control in a lot of civil engineering research currently. In traditional sensor applications, information exchanges with the monitoring center or a computer system through wires. If wireless sensor networks(WSN) technology is used, cabling links is not needed, thus the cost of the whole system is greatly reduced. Based on the above advantages, a wireless control system is designed and validated through preliminary tests. The system consists of a cantilever, PVDF as sensor, signal conditioning circuit(SCM), A/D acquisition board, control arithmetic unit, D/A output board, power amplifier, piezoelectric bimorph as actuator. DSP chip is used as the control arithmetic unit and PD control algorithm is embedded in it. PVDF collects the parameters of vibration, sends them to the SCM after A/D conversion. SCM passes the data to the DSP through wireless technology, and DSP calculates and outputs the control values according to the control algorithm. The output signal is amplified by the power amplifier to drive the piezoelectric bimorph for vibration control. The structural vibration duration reduces to 1/4 of the uncontrolled case, which verifies the feasibility of the system.

  11. GOLD: Integration of model-based control systems with artificial intelligence and workstations

    SciTech Connect

    Lee, M.; Clearwater, S.

    1987-08-01

    Our experience with model based accelerator control started at SPEAR. Since that time nearly all accelerator beam lines have been controlled using model-based application programs, for example, PEP and SLC at SLAC. In order to take advantage of state-of-the-art hardware and software technology, the design and implementation of the accelerator control programs have undergone radical change with time. Consequently, SPEAR, PEP, and SLC all use different control programs. Since many of these application programs are imbedded deep into the control system, they had to be rewritten each time. Each time this rewriting has occurred a great deal of time and effort has been spent on training physicists and programmers to do the job. Now, we have developed these application programs for a fourth time. This time, however, the programs we are developing are generic so that we will not have to do it again. We have developed an integrated system called GOLD (Generic Orbit and Lattice Debugger) for debugging and correcting trajectory errors in accelerator lattices. The system consists of a lattice modeling program (COMFORT), a beam simulator (PLUS), a graphical workstation environment (micro-VAX) and an expert system (ABLE). This paper will describe some of the features and applications of our integrated system with emphasis on the automation offered by expert systems. 5 refs.

  12. GOLD: Integration of model-based control systems with artificial intelligence and workstations

    SciTech Connect

    Lee, M.; Clearwater, S.

    1987-08-01

    Our experience with model-based accelerator control started at SPEAR. Since that time nearly all accelerator beamlines have been controlled using model-based application programs, for example, PEP and SLC at SLAC. In order to take advantage of state-of-the-art hardware and software technology, the design and implementation of the accelerator control programs have undergone radical changes with time. Consequently, SPEAR, PEP and SLC all use different control programs. Since many of these application programs are embedded deep into the control system, they had to be rewritten each time. Each time this rewriting has occurred a great deal of time and effort has been spent on training physicists and programmers to do the job. Now, we have developed an integrated system called GOLD (Genetic Orbit and Lattice Debugger) for debugging and correcting trajectory errors in accelerator lattices. The system consists of a lattice modeling program (COMFORT), a beam simulator (PLUS), a graphical workstation environment (micro-VAX) and an expert system (ABLE). This paper will describe some of the features and applications of our integrated system with emphasis on the automation offered by expert systems. 5 refs.

  13. Observer-based H(infinity) control for networked nonlinear systems with random packet losses.

    PubMed

    Li, Jian Guo; Yuan, Jing Qi; Lu, Jun Guo

    2010-01-01

    This paper investigates the observer-based H(infinity) control problem of networked nonlinear systems with global Lipschitz nonlinearities and random communication packet losses. The random packet loss is modelled as a Bernoulli distributed white sequence with a known conditional probability distribution. In the presence of random packet losses, sufficient conditions for the existence of an observer-based feedback controller are derived, such that the closed-loop networked nonlinear system is exponentially stable in the mean-square sense, and a prescribed H(infinity) disturbance-rejection-attenuation performance is also achieved. Then a linear matrix inequality (LMI) approach for designing such an observer-based H(infinity) controller is presented. Finally, a simulation example is used to demonstrate the effectiveness of the proposed method.

  14. Human factor engineering based design and modernization of control rooms with new I and C systems

    SciTech Connect

    Larraz, J.; Rejas, L.; Ortega, F.

    2012-07-01

    Instrumentation and Control (I and C) systems of the latest nuclear power plants are based on the use of digital technology, distributed control systems and the integration of information in data networks (Distributed Control and Instrumentation Systems). This has a repercussion on Control Rooms (CRs), where the operations and monitoring interfaces correspond to these systems. These technologies are also used in modernizing I and C systems in currently operative nuclear power plants. The new interfaces provide additional capabilities for operation and supervision, as well as a high degree of flexibility, versatility and reliability. An example of this is the implementation of solutions such as compact stations, high level supervision screens, overview displays, computerized procedures, new operational support systems or intelligent alarms processing systems in the modernized Man-Machine Interface (MMI). These changes in the MMI are accompanied by newly added Software (SW) controls and new solutions in automation. Tecnatom has been leading various projects in this area for several years, both in Asian countries and in the United States, using in all cases international standards from which Tecnatom own methodologies have been developed and optimized. The experience acquired in applying this methodology to the design of new control rooms is to a large extent applicable also to the modernization of current control rooms. An adequate design of the interface between the operator and the systems will facilitate safe operation, contribute to the prompt identification of problems and help in the distribution of tasks and communications between the different members of the operating shift. Based on Tecnatom experience in the field, this article presents the methodological approach used as well as the most relevant aspects of this kind of project. (authors)

  15. A new active variable stiffness suspension system using a nonlinear energy sink-based controller

    NASA Astrophysics Data System (ADS)

    Anubi, Olugbenga Moses; Crane, Carl D.

    2013-10-01

    This paper presents the active case of a variable stiffness suspension system. The central concept is based on a recently designed variable stiffness mechanism which consists of a horizontal control strut and a vertical strut. The horizontal strut is used to vary the load transfer ratio by actively controlling the location of the point of attachment of the vertical strut to the car body. The control algorithm, effected by a hydraulic actuator, uses the concept of nonlinear energy sink (NES) to effectively transfer the vibrational energy in the sprung mass to a control mass, thereby reducing the transfer of energy from road disturbance to the car body at a relatively lower cost compared to the traditional active suspension using the skyhook concept. The analyses and simulation results show that a better performance can be achieved by subjecting the point of attachment of a suspension system, to the chassis, to the influence of a horizontal NES system.

  16. A Double-Wing Chaotic System Based on Ion Migration Memristor and Its Sliding Mode Control

    NASA Astrophysics Data System (ADS)

    Min, Guoqi; Duan, Shukai; Wang, Lidan

    The ion migration memristor is a nonlinear element with memory function and nanoscale size, it is considered as a potential candidate to reduce system power consumption and circuit size. When it works as the nonlinear part of the chaotic system, rich nonlinear curves will be produced, and at the same time, the complexity of chaotic systems and the randomness of signals will be enhanced. So in this paper, by Matlab numerical simulation, a new double-wing chaotic system based on an ion migration memristor is designed. In reality, there are many systems interfered inevitably by random noise, so in this paper the random bounded noises are also considered. The power spectrum, Lyapunov exponent spectrum, Poincaré map and bifurcation diagram are used to investigate its complex dynamic characteristics. Then, a SPICE-based analog circuit is presented to verify the feasibility of the system, for which the simulation results are consistent with the numerical simulation. Finally, the sliding mode variable structure control is applied to overcome the shortcomings of traditional control method, so that the chaotic orbits can be controlled to any fixed points or periodic orbits, and this provides an insight into chaos control in power electronics systems.

  17. Knowledge-based monitoring of the pointing control system on the Hubble space telescope

    NASA Technical Reports Server (NTRS)

    Dunham, Larry L.; Laffey, Thomas J.; Kao, Simon M.; Schmidt, James L.; Read, Jackson Y.

    1987-01-01

    A knowledge-based system for the real time monitoring of telemetry data from the Pointing and Control System (PCS) of the Hubble Space Telescope (HST) that enables the retention of design expertise throughout the three decade project lifespan by means other than personnel and documentation is described. The system will monitor performance, vehicle status, success or failure of various maneuvers, and in some cases diagnose problems and recommend corrective actions using a knowledge base built using mission scenarios and the more than 4,500 telemetry monitors from the HST.

  18. Utility-Side Voltage and PQ Control with Inverter-based Photovoltaic Systems

    SciTech Connect

    Adhikari, Sarina; Xu, Yan; Li, Fangxing; Li, Huijuan; Kueck, John D; Snyder, Isabelle B; Barker, Thomas J.; Hite, Ronald

    2011-01-01

    Distributed energy resources (DER) are small generators located close to the load centers. The DERs that are integrated to the grid with the power electronic converter interfaces are capable of providing nonactive power in addition to active power. Hence, they are capable of regulating the voltages of the weak buses in the distribution systems. This paper discusses the voltage control capability of photovoltaic (PV) systems as compared to the traditional capacitor banks. The simulation results prove the effectiveness of dynamic voltage control capability of inverter-based PV. With the proper control algorithm, the active and nonactive power from the DERs like battery banks or solar photovoltaic can be controlled independently. This paper also presents the scenario of controlling the active and nonactive power from the PV array to track and supply the local load.

  19. Brain limbic system-based intelligent controller application to lane change manoeuvre

    NASA Astrophysics Data System (ADS)

    Kim, Changwon; Langari, Reza

    2011-12-01

    This paper presents the application of a novel neuromorphic control strategy for lane change manoeuvres in the highway environment. The lateral dynamics of a vehicle with and without wind disturbance are derived and utilised to implement a control strategy based on the brain limbic system. To show the robustness of the proposed controller, several disturbance conditions including wind, uncertainty in the cornering stiffness, and changes in the vehicle mass are investigated. To demonstrate the performance of the suggested strategy, simulation results of the proposed method are compared with the human driver model-based control scheme, which has been discussed in the literature. The simulation results demonstrate the superiority of the proposed controller in energy efficiency, driving comfort, and robustness.

  20. Intermittent observer-based consensus control for multi-agent systems with switching topologies

    NASA Astrophysics Data System (ADS)

    Xu, Xiaole; Gao, Lixin

    2016-06-01

    In this paper, we focus on the consensus problem for leaderless and leader-followers multi-agent systems with periodically intermittent control. The dynamics of each agent in the system is a linear system, and the interconnection topology among the agents is assumed to be switching. We assume that each agent can only share the outputs with its neighbours. Therefore, a class of distributed intermittent observer-based consensus protocols are proposed for each agent. First, in order to solve this problem, a parameter-dependent common Lyapunov function is constructed. Using this function, we prove that all agents can access a prescribed value, under the designed intermittent controller and observer, if there are suitable conditions on communication. Second, based on the investigation of the leader-following consensus problem, we design a new distributed intermittent observer-based protocol for each following agent. Finally, we provide an illustrative example to verify the effectiveness of the proposed approach.

  1. Integrated control of lateral and vertical vehicle dynamics based on multi-agent system

    NASA Astrophysics Data System (ADS)

    Huang, Chen; Chen, Long; Yun, Chaochun; Jiang, Haobin; Chen, Yuexia

    2014-03-01

    The existing research of the integrated chassis control mainly focuses on the different evaluation indexes and control strategy. Among the different evaluation indexes, the comprehensive properties are usually not considered based on the non-linear superposition principle. But, the control strategy has some shortages on tyre model with side-slip angle, road adhesion coefficient, vertical load and velocity. In this paper, based on belief, desire and intention(BDI)-agent model framework, the TYRE agent, electric power steering(EPS) agent and active suspension system(ASS) agent are proposed. In the system(SYS) agent, the coordination mechanism is employed to manage interdependences and conflicts among other agents, so as to improve the flexibility, adaptability, and robustness of the global control system. Due to the existence of the simulation demand of dynamic performance, the vehicle multi-body dynamics model is established by SIMPACK. And then the co-simulation analysis is conducted to evaluate the proposed multi-agent system(MAS) controller. The simulation results demonstrate that the MAS has good effect on the performance of EPS and ASS. Meantime, the better road feeling for the driver is provided considering the multiple and complex driving traffic. Finally, the MAS rapid control prototyping is built to conduct the real vehicle test. The test results are consistent to the simulation results, which verifies the correctness of simulation. The proposed research ensures the driving safety, enhances the handling stability, and improves the ride comfort.

  2. Attractant-based systems as pesticide alternatives for control of tropical fruit flies (Diptera: Tephritidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mass trapping and attract-and-kill bait stations are two attractant based systems that are being used or are under development as pesticide alternatives for control of a number of pest tephritid fruit flies. Results of field trials for suppression of Caribbean fruit flies in guava orchards in Florid...

  3. A Study on Components of Internal Control-Based Administrative System in Secondary Schools

    ERIC Educational Resources Information Center

    Montri, Paitoon; Sirisuth, Chaiyuth; Lammana, Preeda

    2015-01-01

    The aim of this study was to study the components of the internal control-based administrative system in secondary schools, and make a Confirmatory Factor Analysis (CFA) to confirm the goodness of fit of empirical data and component model that resulted from the CFA. The study consisted of three steps: 1) studying of principles, ideas, and theories…

  4. Robustness of delayed multistable systems with application to droop-controlled inverter-based microgrids

    NASA Astrophysics Data System (ADS)

    Efimov, Denis; Schiffer, Johannes; Ortega, Romeo

    2016-05-01

    Motivated by the problem of phase-locking in droop-controlled inverter-based microgrids with delays, the recently developed theory of input-to-state stability (ISS) for multistable systems is extended to the case of multistable systems with delayed dynamics. Sufficient conditions for ISS of delayed systems are presented using Lyapunov-Razumikhin functions. It is shown that ISS multistable systems are robust with respect to delays in a feedback. The derived theory is applied to two examples. First, the ISS property is established for the model of a nonlinear pendulum and delay-dependent robustness conditions are derived. Second, it is shown that, under certain assumptions, the problem of phase-locking analysis in droop-controlled inverter-based microgrids with delays can be reduced to the stability investigation of the nonlinear pendulum. For this case, corresponding delay-dependent conditions for asymptotic phase-locking are given.

  5. PDX diagnostic control system

    SciTech Connect

    Mika, R.

    1981-01-01

    This paper describes a computer-base diagnostic control system operating on the PDX Tokamak. The prime function of the system is to control mechanical positioning devices associated with various diagnostics including Thomson Scattering, X-Ray Pulse Height Analyzer, Rotating Scanning Monochromator, Fast Ion Detection Experiment, Bolometers and Plasma Limiters. The diagnostic control system consists of a PDP-11/34 computer, a CAMAC system partitioned between the PDX control room and the PDX machine area, and special electronic control modules developed at PPL. The special modules include a digital closed loop motor controller and user interface control panel for control and status display. A standard control panel was developed for interfacing each system user with the PDP-11/34 computer, through specially developed CAMAC modules.

  6. Multi-agent based control of large-scale complex systems employing distributed dynamic inference engine

    NASA Astrophysics Data System (ADS)

    Zhang, Daili

    Increasing societal demand for automation has led to considerable efforts to control large-scale complex systems, especially in the area of autonomous intelligent control methods. The control system of a large-scale complex system needs to satisfy four system level requirements: robustness, flexibility, reusability, and scalability. Corresponding to the four system level requirements, there arise four major challenges. First, it is difficult to get accurate and complete information. Second, the system may be physically highly distributed. Third, the system evolves very quickly. Fourth, emergent global behaviors of the system can be caused by small disturbances at the component level. The Multi-Agent Based Control (MABC) method as an implementation of distributed intelligent control has been the focus of research since the 1970s, in an effort to solve the above-mentioned problems in controlling large-scale complex systems. However, to the author's best knowledge, all MABC systems for large-scale complex systems with significant uncertainties are problem-specific and thus difficult to extend to other domains or larger systems. This situation is partly due to the control architecture of multiple agents being determined by agent to agent coupling and interaction mechanisms. Therefore, the research objective of this dissertation is to develop a comprehensive, generalized framework for the control system design of general large-scale complex systems with significant uncertainties, with the focus on distributed control architecture design and distributed inference engine design. A Hybrid Multi-Agent Based Control (HyMABC) architecture is proposed by combining hierarchical control architecture and module control architecture with logical replication rings. First, it decomposes a complex system hierarchically; second, it combines the components in the same level as a module, and then designs common interfaces for all of the components in the same module; third, replications

  7. Model based manipulator control

    NASA Technical Reports Server (NTRS)

    Petrosky, Lyman J.; Oppenheim, Irving J.

    1989-01-01

    The feasibility of using model based control (MBC) for robotic manipulators was investigated. A double inverted pendulum system was constructed as the experimental system for a general study of dynamically stable manipulation. The original interest in dynamically stable systems was driven by the objective of high vertical reach (balancing), and the planning of inertially favorable trajectories for force and payload demands. The model-based control approach is described and the results of experimental tests are summarized. Results directly demonstrate that MBC can provide stable control at all speeds of operation and support operations requiring dynamic stability such as balancing. The application of MBC to systems with flexible links is also discussed.

  8. Anticipatory Monitoring and Control of Complex Systems using a Fuzzy based Fusion of Support Vector Regressors

    SciTech Connect

    Miltiadis Alamaniotis; Vivek Agarwal

    2014-10-01

    This paper places itself in the realm of anticipatory systems and envisions monitoring and control methods being capable of making predictions over system critical parameters. Anticipatory systems allow intelligent control of complex systems by predicting their future state. In the current work, an intelligent model aimed at implementing anticipatory monitoring and control in energy industry is presented and tested. More particularly, a set of support vector regressors (SVRs) are trained using both historical and observed data. The trained SVRs are used to predict the future value of the system based on current operational system parameter. The predicted values are then inputted to a fuzzy logic based module where the values are fused to obtain a single value, i.e., final system output prediction. The methodology is tested on real turbine degradation datasets. The outcome of the approach presented in this paper highlights the superiority over single support vector regressors. In addition, it is shown that appropriate selection of fuzzy sets and fuzzy rules plays an important role in improving system performance.

  9. A Bragg grating tunable filter based on temperature control system to demodulate a voltage sensor

    NASA Astrophysics Data System (ADS)

    Ribeiro, Bessie A.; Werneck, Marcelo M.; de Nazaré, Fabio B. V.; Gonçalves, Marceli N.

    2015-09-01

    This work presents an innovative automated Fiber Bragg Grating (FBG) based tunable optical filter (TOF) controlled by temperature to be used in temperature compensating schemes in FBG sensing set-ups. Mechanical and electronic aspects are discussed, and the implemented FBG-TOF viability and reliability in sensing systems are showed. The system was employed to demodulate a high voltage AC signal applied to a FBG-PZT sensor, showing good linearity and sensitivity.

  10. Implementation of fuzzy-sliding mode based control of a grid connected photovoltaic system.

    PubMed

    Menadi, Abdelkrim; Abdeddaim, Sabrina; Ghamri, Ahmed; Betka, Achour

    2015-09-01

    The present work describes an optimal operation of a small scale photovoltaic system connected to a micro-grid, based on both sliding mode and fuzzy logic control. Real time implementation is done through a dSPACE 1104 single board, controlling a boost chopper on the PV array side and a voltage source inverter (VSI) on the grid side. The sliding mode controller tracks permanently the maximum power of the PV array regardless of atmospheric condition variations, while The fuzzy logic controller (FLC) regulates the DC-link voltage, and ensures via current control of the VSI a quasi-total transit of the extracted PV power to the grid under a unity power factor operation. Simulation results, carried out via Matlab-Simulink package were approved through experiment, showing the effectiveness of the proposed control techniques. PMID:26243440

  11. Implementation of fuzzy-sliding mode based control of a grid connected photovoltaic system.

    PubMed

    Menadi, Abdelkrim; Abdeddaim, Sabrina; Ghamri, Ahmed; Betka, Achour

    2015-09-01

    The present work describes an optimal operation of a small scale photovoltaic system connected to a micro-grid, based on both sliding mode and fuzzy logic control. Real time implementation is done through a dSPACE 1104 single board, controlling a boost chopper on the PV array side and a voltage source inverter (VSI) on the grid side. The sliding mode controller tracks permanently the maximum power of the PV array regardless of atmospheric condition variations, while The fuzzy logic controller (FLC) regulates the DC-link voltage, and ensures via current control of the VSI a quasi-total transit of the extracted PV power to the grid under a unity power factor operation. Simulation results, carried out via Matlab-Simulink package were approved through experiment, showing the effectiveness of the proposed control techniques.

  12. A general U-block model-based design procedure for nonlinear polynomial control systems

    NASA Astrophysics Data System (ADS)

    Zhu, Q. M.; Zhao, D. Y.; Zhang, Jianhua

    2016-10-01

    The proposition of U-model concept (in terms of 'providing concise and applicable solutions for complex problems') and a corresponding basic U-control design algorithm was originated in the first author's PhD thesis. The term of U-model appeared (not rigorously defined) for the first time in the first author's other journal paper, which established a framework for using linear polynomial control system design approaches to design nonlinear polynomial control systems (in brief, linear polynomial approaches → nonlinear polynomial plants). This paper represents the next milestone work - using linear state-space approaches to design nonlinear polynomial control systems (in brief, linear state-space approaches → nonlinear polynomial plants). The overall aim of the study is to establish a framework, defined as the U-block model, which provides a generic prototype for using linear state-space-based approaches to design the control systems with smooth nonlinear plants/processes described by polynomial models. For analysing the feasibility and effectiveness, sliding mode control design approach is selected as an exemplary case study. Numerical simulation studies provide a user-friendly step-by-step procedure for the readers/users with interest in their ad hoc applications. In formality, this is the first paper to present the U-model-oriented control system design in a formal way and to study the associated properties and theorems. The previous publications, in the main, have been algorithm-based studies and simulation demonstrations. In some sense, this paper can be treated as a landmark for the U-model-based research from intuitive/heuristic stage to rigour/formal/comprehensive studies.

  13. Knowledge based system for runtime controlling of multiscale model of ion-exchange solvent extraction

    NASA Astrophysics Data System (ADS)

    Macioł, Piotr; Gotfryd, Leszek; Macioł, Andrzej

    2012-09-01

    The hereby paper concerns the issue of solution of runtime controlling of multiscale model of ion-exchange solvent extraction. It is based on cooperation of a framework applying Agile Multiscale Modeling Methodology (AM3), and the REBIT Knowledge Based System. Ion-exchange solvent extraction has been shortly introduced. Design assumptions of AM3 and theoretical basis of REBIT have been described. Designed workflows and rules for simple laminar/ turbulent flow and extraction processes have been shown.

  14. Linear matrix inequality-based nonlinear adaptive robust control with application to unmanned aircraft systems

    NASA Astrophysics Data System (ADS)

    Kun, David William

    Unmanned aircraft systems (UASs) are gaining popularity in civil and commercial applications as their lightweight on-board computers become more powerful and affordable, their power storage devices improve, and the Federal Aviation Administration addresses the legal and safety concerns of integrating UASs in the national airspace. Consequently, many researchers are pursuing novel methods to control UASs in order to improve their capabilities, dependability, and safety assurance. The nonlinear control approach is a common choice as it offers several benefits for these highly nonlinear aerospace systems (e.g., the quadrotor). First, the controller design is physically intuitive and is derived from well known dynamic equations. Second, the final control law is valid in a larger region of operation, including far from the equilibrium states. And third, the procedure is largely methodical, requiring less expertise with gain tuning, which can be arduous for a novice engineer. Considering these facts, this thesis proposes a nonlinear controller design method that combines the advantages of adaptive robust control (ARC) with the powerful design tools of linear matrix inequalities (LMI). The ARC-LMI controller is designed with a discontinuous projection-based adaptation law, and guarantees a prescribed transient and steady state tracking performance for uncertain systems in the presence of matched disturbances. The norm of the tracking error is bounded by a known function that depends on the controller design parameters in a known form. Furthermore, the LMI-based part of the controller ensures the stability of the system while overcoming polytopic uncertainties, and minimizes the control effort. This can reduce the number of parameters that require adaptation, and helps to avoid control input saturation. These desirable characteristics make the ARC-LMI control algorithm well suited for the quadrotor UAS, which may have unknown parameters and may encounter external

  15. RTDS implementation of an improved sliding mode based inverter controller for PV system.

    PubMed

    Islam, Gazi; Muyeen, S M; Al-Durra, Ahmed; Hasanien, Hany M

    2016-05-01

    This paper proposes a novel approach for testing dynamics and control aspects of a large scale photovoltaic (PV) system in real time along with resolving design hindrances of controller parameters using Real Time Digital Simulator (RTDS). In general, the harmonic profile of a fast controller has wide distribution due to the large bandwidth of the controller. The major contribution of this paper is that the proposed control strategy gives an improved voltage harmonic profile and distribute it more around the switching frequency along with fast transient response; filter design, thus, becomes easier. The implementation of a control strategy with high bandwidth in small time steps of Real Time Digital Simulator (RTDS) is not straight forward. This paper shows a good methodology for the practitioners to implement such control scheme in RTDS. As a part of the industrial process, the controller parameters are optimized using particle swarm optimization (PSO) technique to improve the low voltage ride through (LVRT) performance under network disturbance. The response surface methodology (RSM) is well adapted to build analytical models for recovery time (Rt), maximum percentage overshoot (MPOS), settling time (Ts), and steady state error (Ess) of the voltage profile immediate after inverter under disturbance. A systematic approach of controller parameter optimization is detailed. The transient performance of the PSO based optimization method applied to the proposed sliding mode controlled PV inverter is compared with the results from genetic algorithm (GA) based optimization technique. The reported real time implementation challenges and controller optimization procedure are applicable to other control applications in the field of renewable and distributed generation systems. PMID:26606852

  16. RTDS implementation of an improved sliding mode based inverter controller for PV system.

    PubMed

    Islam, Gazi; Muyeen, S M; Al-Durra, Ahmed; Hasanien, Hany M

    2016-05-01

    This paper proposes a novel approach for testing dynamics and control aspects of a large scale photovoltaic (PV) system in real time along with resolving design hindrances of controller parameters using Real Time Digital Simulator (RTDS). In general, the harmonic profile of a fast controller has wide distribution due to the large bandwidth of the controller. The major contribution of this paper is that the proposed control strategy gives an improved voltage harmonic profile and distribute it more around the switching frequency along with fast transient response; filter design, thus, becomes easier. The implementation of a control strategy with high bandwidth in small time steps of Real Time Digital Simulator (RTDS) is not straight forward. This paper shows a good methodology for the practitioners to implement such control scheme in RTDS. As a part of the industrial process, the controller parameters are optimized using particle swarm optimization (PSO) technique to improve the low voltage ride through (LVRT) performance under network disturbance. The response surface methodology (RSM) is well adapted to build analytical models for recovery time (Rt), maximum percentage overshoot (MPOS), settling time (Ts), and steady state error (Ess) of the voltage profile immediate after inverter under disturbance. A systematic approach of controller parameter optimization is detailed. The transient performance of the PSO based optimization method applied to the proposed sliding mode controlled PV inverter is compared with the results from genetic algorithm (GA) based optimization technique. The reported real time implementation challenges and controller optimization procedure are applicable to other control applications in the field of renewable and distributed generation systems.

  17. A microprocessor-based control system for the Vienna PDS microdensitometer

    NASA Technical Reports Server (NTRS)

    Jenkner, H.; Stoll, M.; Hron, J.

    1984-01-01

    The Motorola Exorset 30 system, based on a Motorola 6809 microprocessor which serves as control processor for the microdensitometer is presented. User communication and instrument control are implemented in this syatem; data transmission to a host computer is provided via standard interfaces. The Vienna PDS system (VIPS) software was developed in BASIC and M6809 assembler. It provides efficient user interaction via function keys and argument input in a menu oriented environment. All parameters can be stored on, and retrieved from, minifloppy disks, making it possible to set up large scanning tasks. Extensive user information includes continuously updated status and coordinate displays, as well as a real time graphic display during scanning.

  18. Effect of vibrotactile feedback on an EMG-based proportional cursor control system.

    PubMed

    Li, Shunchong; Chen, Xingyu; Zhang, Dingguo; Sheng, Xinjun; Zhu, Xiangyang

    2013-01-01

    Surface electromyography (sEMG) has been introduced into the bio-mechatronics systems, however, most of them are lack of the sensory feedback. In this paper, the effect of vibrotactile feedback for a myoelectric cursor control system is investigated quantitatively. Simultaneous and proportional control signals are extracted from EMG using a muscle synergy model. Different types of feedback including vibrotactile feedback and visual feedback are added, assessed and compared with each other. The results show that vibrotactile feedback is capable of improving the performance of EMG-based human machine interface.

  19. Supervisory control design based on hybrid systems and fuzzy events detection. Application to an oxichlorination reactor.

    PubMed

    Altamiranda, Edmary; Torres, Horacio; Colina, Eliezer; Chacón, Edgar

    2002-10-01

    This paper presents a supervisory control scheme based on hybrid systems theory and fuzzy events detection. The fuzzy event detector is a linguistic model, which synthesizes complex relations between process variables and process events incorporating experts' knowledge about the process operation. This kind of detection allows the anticipation of appropriate control actions, which depend upon the selected membership functions used to characterize the process under scrutiny. The proposed supervisory control scheme was successfully implemented for an oxichlorination reactor in a vinyl monomer plant. This implementation has allowed improvement of reactor stability and reduction of raw material consumption. PMID:12398279

  20. Web Design Based on Integrated and Supervision Control System in City Rail Transit

    NASA Astrophysics Data System (ADS)

    Li, Xiaojuan; Xing, Yu; Zheng, Hengchao

    This paper presents a method of setting up WEB System to Integrated Supervision Control System for the requirements of city Rail Transit. First, basic platform and software/hardware architecture of WEB System are discussed. Then the function module, data flow and communication mechanisms are described and a design based on technologies of SVG and Ajax is proposed and the WEB video release function and system security are described. This design makes it possible that important information of Integrated Supervision Control System can be browsed and queried in external Web pages. Watching Real-time images of all cameras in internal network of Rail Transit is possible, which is providing remote viewing and management functions for metro managers.

  1. Quality control of software in dissimilar systems using a common clinical data base

    SciTech Connect

    Erickson, J. J.; Price, R. R.; Touya, J. J.; Kronenberg, M. W.; Pederson, R.; Rollo, F. D.

    1980-01-01

    For a long time there has been widespread interest in the quality control of diagnostic instrumentation. The increasing dependence on computational systems for clinical results makes it imperative that methods for quality control of diagnostic software be developed. This paper proposes a method based on the use of a collection of patient studies for which the results have been corroborated by independent methods. The data set will be distributed in a format requiring no special handling by the system being tested and will appear identical to studies actually collected by the host system. An example of the use of a preliminary version of the data set for comparison of two systems is shown. The comparison shows that analyses performed on the two systems agree very well and can be reliably compared for follow-up studies of a patient.

  2. Robot Arm Control and Having Meal Aid System with Eye Based Human-Computer Interaction (HCI)

    NASA Astrophysics Data System (ADS)

    Arai, Kohei; Mardiyanto, Ronny

    Robot arm control and having meal aid system with eye based HCI is proposed. The proposed system allows disabled person to select desirable food from the meal tray by their eyes only. Robot arm which is used for retrieving the desirable food is controlled by human eye. At the tip of the robot arm, tiny camera is equipped. Disabled person wear a glass of which a single Head Mount Display: HMD and tiny camera is mounted so that disabled person can take a look at the desired food and retrieve it by looking at the food displayed onto HMD. Experimental results show that disabled person can retrieve the desired food successfully. It also is confirmed that robot arm control by eye based HCI is much faster than that by hands.

  3. Selected Flight Test Results for Online Learning Neural Network-Based Flight Control System

    NASA Technical Reports Server (NTRS)

    Williams-Hayes, Peggy S.

    2004-01-01

    The NASA F-15 Intelligent Flight Control System project team developed a series of flight control concepts designed to demonstrate neural network-based adaptive controller benefits, with the objective to develop and flight-test control systems using neural network technology to optimize aircraft performance under nominal conditions and stabilize the aircraft under failure conditions. This report presents flight-test results for an adaptive controller using stability and control derivative values from an online learning neural network. A dynamic cell structure neural network is used in conjunction with a real-time parameter identification algorithm to estimate aerodynamic stability and control derivative increments to baseline aerodynamic derivatives in flight. This open-loop flight test set was performed in preparation for a future phase in which the learning neural network and parameter identification algorithm output would provide the flight controller with aerodynamic stability and control derivative updates in near real time. Two flight maneuvers are analyzed - pitch frequency sweep and automated flight-test maneuver designed to optimally excite the parameter identification algorithm in all axes. Frequency responses generated from flight data are compared to those obtained from nonlinear simulation runs. Flight data examination shows that addition of flight-identified aerodynamic derivative increments into the simulation improved aircraft pitch handling qualities.

  4. PSO-tuned PID controller for coupled tank system via priority-based fitness scheme

    NASA Astrophysics Data System (ADS)

    Jaafar, Hazriq Izzuan; Hussien, Sharifah Yuslinda Syed; Selamat, Nur Asmiza; Abidin, Amar Faiz Zainal; Aras, Mohd Shahrieel Mohd; Nasir, Mohamad Na'im Mohd; Bohari, Zul Hasrizal

    2015-05-01

    The industrial applications of Coupled Tank System (CTS) are widely used especially in chemical process industries. The overall process is require liquids to be pumped, stored in the tank and pumped again to another tank. Nevertheless, the level of liquid in tank need to be controlled and flow between two tanks must be regulated. This paper presents development of an optimal PID controller for controlling the desired liquid level of the CTS. Two method of Particle Swarm Optimization (PSO) algorithm will be tested in optimizing the PID controller parameters. These two methods of PSO are standard Particle Swarm Optimization (PSO) and Priority-based Fitness Scheme in Particle Swarm Optimization (PFPSO). Simulation is conducted within Matlab environment to verify the performance of the system in terms of settling time (Ts), steady state error (SSE) and overshoot (OS). It has been demonstrated that implementation of PSO via Priority-based Fitness Scheme (PFPSO) for this system is potential technique to control the desired liquid level and improve the system performances compared with standard PSO.

  5. Vibration isolation and reduction by spring-stiffness control based on theory of variable structure systems

    SciTech Connect

    Yamaguchi, H.; Shioya, S.; Oda, M.

    1995-12-31

    By controlling spring stiffness, vibration reduction and isolation for the mass-spring system are achieved in this paper. The control algorithm of the spring stiffness is based on the variable structure systems (VSS) theory. The stiffness-controllable spring is achieved by using two straight bars that are hinged to the mass in a line perpendicular to the direction of mass motion and are applied axial force. Since the axial force causes restoring force equivalent to the spring, the stiffness is controlled by the axial force. In the numerical simulations and experiments, the settling time of the impulse response and the displacement transmissibility are investigated. The results show that the proposed method is effective in suppressing shock motion and isolating vibration transmitted from the floor.

  6. Adaptive sliding mode controller based on super-twist observer for tethered satellite system

    NASA Astrophysics Data System (ADS)

    Keshtkar, Sajjad; Poznyak, Alexander

    2016-09-01

    In this work, the sliding mode control based on the super-twist observer is presented. The parameters of the controller as well as the observer are admitted to be time-varying and depending on available current measurements. In view of that, the considered controller is referred to as an adaptive one. It is shown that the deviations of the generated state estimates from real state values together with a distance of the closed-loop system trajectories to a desired sliding surface reach a μ-zone around the origin in finite time. The application of the suggested controller is illustrated for the orientation of a tethered satellite system in a required position.

  7. Using a geographical-information-system-based decision support to enhance malaria vector control in zambia.

    PubMed

    Chanda, Emmanuel; Mukonka, Victor Munyongwe; Mthembu, David; Kamuliwo, Mulakwa; Coetzer, Sarel; Shinondo, Cecilia Jill

    2012-01-01

    Geographic information systems (GISs) with emerging technologies are being harnessed for studying spatial patterns in vector-borne diseases to reduce transmission. To implement effective vector control, increased knowledge on interactions of epidemiological and entomological malaria transmission determinants in the assessment of impact of interventions is critical. This requires availability of relevant spatial and attribute data to support malaria surveillance, monitoring, and evaluation. Monitoring the impact of vector control through a GIS-based decision support (DSS) has revealed spatial relative change in prevalence of infection and vector susceptibility to insecticides and has enabled measurement of spatial heterogeneity of trend or impact. The revealed trends and interrelationships have allowed the identification of areas with reduced parasitaemia and increased insecticide resistance thus demonstrating the impact of resistance on vector control. The GIS-based DSS provides opportunity for rational policy formulation and cost-effective utilization of limited resources for enhanced malaria vector control.

  8. Real-time data acquisition and telemetry based irrigation control system

    DOEpatents

    Slater, John M.; Svoboda, John M.

    2005-12-13

    A data acquisition and telemetry based control system for use in facilitating substantially real time management of an agricultural irrigation system. The soil moisture sensor includes a reader and a plurality of probes. The probes each include an electronic circuit having a moisture sensing capacitor in operative communication with the soil whose moisture is to be measured. Each probe also includes a receive/transmit antenna and the reader includes a transmit/receive antenna, so that as the reader passes near the probe, the reader transmits a digital excitation signal to the electronic circuit of the biodegradable probe via an inductive couple formed between the transmit/receive antenna of the reader and the receive/transmit coil of the probe. The electronic circuit uses an energy component of the excitation signal to generate a digital data signal which indicates the moisture content of the soil adjacent to the moisture sensing capacitor. The probe sends the data signal to the reader which then uses the data signal to develop a corresponding set of watering instructions which are then transmitted to a control module in communication with the irrigation system. The control module sends corresponding control signals to nozzles of the irrigation system causing the irrigation system to disperse water in a manner consistent with the moisture content data transmitted by the probes to the reader. Because the irrigation system moves continuously through the field to be irrigated, the moisture content data acquisition and resultant water dispersal by the irrigation system occur substantially in real time.

  9. Method and system to perform energy-extraction based active noise control

    NASA Technical Reports Server (NTRS)

    Kelkar, Atul (Inventor); Joshi, Suresh M. (Inventor)

    2009-01-01

    A method to provide active noise control to reduce noise and vibration in reverberant acoustic enclosures such as aircraft, vehicles, appliances, instruments, industrial equipment and the like is presented. A continuous-time multi-input multi-output (MIMO) state space mathematical model of the plant is obtained via analytical modeling and system identification. Compensation is designed to render the mathematical model passive in the sense of mathematical system theory. The compensated system is checked to ensure robustness of the passive property of the plant. The check ensures that the passivity is preserved if the mathematical model parameters are perturbed from nominal values. A passivity-based controller is designed and verified using numerical simulations and then tested. The controller is designed so that the resulting closed-loop response shows the desired noise reduction.

  10. Boiler control systems engineering

    SciTech Connect

    Gilman, J.

    2005-07-01

    The book provides in-depth coverage on how to safely and reliably control the firing of a boiler. Regardless of the capacity or fuel, certain fundamental control systems are required for boiler control. Large utility systems are more complex due to the number of burners and the overall capacity and equipment. This book covers engineering details on control systems and provides specific examples of boiler control including configuration and tuning. References to requirements are based on the 2004 NFPA 85 along with other ISA standards. Detailed chapters cover: Boiler fundamentals including piping and instrument diagrams (P&IDs) and a design basis checklist; Control of boilers, from strategies and bumpless transfer to interlock circuitry and final control elements; Furnace draft; Feedwater; Coal-fired boilers; Fuel and air control; Steam temperature; Burner management systems; Environment; and Control valve sizing. 2 apps.

  11. Impact of dither-based Electro-Optic Modulator bias control on distributed Brillouin sensing system

    NASA Astrophysics Data System (ADS)

    Sun, Qiao; Tu, Xiaobo; Sun, Shilin; Hu, Xiaoyang; Meng, Zhou

    2015-10-01

    In most distributed Brillouin sensing systems, it is crucial to keep the long-term stability of the electro-optic modulator (EOM) operating point. The dither-tone based bias control methods are widely adopted in this kind of systems for its robustness and reliability, but the low frequency dither tone (a few kilohertz) added into the dc bias port of the EOM may have a detrimental impact on the sensing performance of the Brillouin sensing system. Experimental results show that the dither frequency should not be set around quarter of the pulse repetition rate or its multiples, and the employed dither amplitude should be in the range of 0.003Vπ to 0.015Vπ (Vπ is the RF half-wave voltage of the EOM), in order to overcome the limitation of dither tone based bias control techniques in BOTDA systems. These results will provide guidelines to improve the performance of the Brillouin sensing systems using dither-based EOM bias control method.

  12. Algorithms for sum-of-squares-based stability analysis and control design of uncertain nonlinear systems

    NASA Astrophysics Data System (ADS)

    Ataei-Esfahani, Armin

    In this dissertation, we present algorithmic procedures for sum-of-squares based stability analysis and control design for uncertain nonlinear systems. In particular, we consider the case of robust aircraft control design for a hypersonic aircraft model subject to parametric uncertainties in its aerodynamic coefficients. In recent years, Sum-of-Squares (SOS) method has attracted increasing interest as a new approach for stability analysis and controller design of nonlinear dynamic systems. Through the application of SOS method, one can describe a stability analysis or control design problem as a convex optimization problem, which can efficiently be solved using Semidefinite Programming (SDP) solvers. For nominal systems, the SOS method can provide a reliable and fast approach for stability analysis and control design for low-order systems defined over the space of relatively low-degree polynomials. However, The SOS method is not well-suited for control problems relating to uncertain systems, specially those with relatively high number of uncertainties or those with non-affine uncertainty structure. In order to avoid issues relating to the increased complexity of the SOS problems for uncertain system, we present an algorithm that can be used to transform an SOS problem with uncertainties into a LMI problem with uncertainties. A new Probabilistic Ellipsoid Algorithm (PEA) is given to solve the robust LMI problem, which can guarantee the feasibility of a given solution candidate with an a-priori fixed probability of violation and with a fixed confidence level. We also introduce two approaches to approximate the robust region of attraction (RROA) for uncertain nonlinear systems with non-affine dependence on uncertainties. The first approach is based on a combination of PEA and SOS method and searches for a common Lyapunov function, while the second approach is based on the generalized Polynomial Chaos (gPC) expansion theorem combined with the SOS method and searches

  13. Slim-structured electro-floating display system based on the polarization-controlled optical path.

    PubMed

    Kim, Seung-Cheol; Park, Seong-Jin; Kim, Eun-Soo

    2016-04-18

    A new slim-type electro-floating display system based on the polarization-controlled optical path is proposed. In the proposed system, the optical path between the input plane and Fresnel lens can be made recursive by repetitive transmission and reflection of the input beam by employing a new polarization-based optical path controller (P-OPC), which is composed of two quaterwave plates, a half mirror and a reflective polarizer. Based on this P-OPC, the absolute optical path between the input plane and Fresnel lens, virtually representing the physical depth of the display system, can be reduced down to one third of its original path, which results in the same rate of decrease in the volume size of the display system. The operational principle of the proposed system is analyzed with the Jones matrix. In addition, to confirm the feasibility of the proposed system, experiments with test prototypes are carried out, and the results are comparatively discussed with those of the conventional system.

  14. Promise of a low power mobile CPU based embedded system in artificial leg control.

    PubMed

    Hernandez, Robert; Zhang, Fan; Zhang, Xiaorong; Huang, He; Yang, Qing

    2012-01-01

    This paper presents the design and implementation of a low power embedded system using mobile processor technology (Intel Atom™ Z530 Processor) specifically tailored for a neural-machine interface (NMI) for artificial limbs. This embedded system effectively performs our previously developed NMI algorithm based on neuromuscular-mechanical fusion and phase-dependent pattern classification. The analysis shows that NMI embedded system can meet real-time constraints with high accuracies for recognizing the user's locomotion mode. Our implementation utilizes the mobile processor efficiently to allow a power consumption of 2.2 watts and low CPU utilization (less than 4.3%) while executing the complex NMI algorithm. Our experiments have shown that the highly optimized C program implementation on the embedded system has superb advantages over existing PC implementations on MATLAB. The study results suggest that mobile-CPU-based embedded system is promising for implementing advanced control for powered lower limb prostheses.

  15. Tuning of IMC based PID controllers for integrating systems with time delay.

    PubMed

    Kumar, D B Santosh; Padma Sree, R

    2016-07-01

    Design of Proportional Integral and Derivative (PID) controllers based on IMC principles for various types of integrating systems with time delay is proposed. PID parameters are given in terms of process model parameters and a tuning parameter. The tuning parameter is IMC filter time constant. In the present work, the IMC filter (Q) is chosen in such a manner that the order of the denominator of IMC controller is one less than the order of the numerator. The IMC filter time constant (λ) is tuned in such a way that a good compromise is made between performance and robustness for both servo and regulatory problems. To improve servo response of the controller a set point filter is designed such that the closed loop response is similar to that of first order plus time delay system. The proposed controller design method is applied to various transfer function models and to the non-linear model equations of jacketed CSTR to demonstrate its applicability and effectiveness. The performance of the proposed controller is compared with the recently reported methods in terms of IAE and ITAE. The smooth functioning of the controller is determined in terms of total variation and compared with recently reported methods. Simulation studies are carried out on various integrating systems with time delay to show the effectiveness and superiority of the proposed controllers. PMID:27087135

  16. Tuning of IMC based PID controllers for integrating systems with time delay.

    PubMed

    Kumar, D B Santosh; Padma Sree, R

    2016-07-01

    Design of Proportional Integral and Derivative (PID) controllers based on IMC principles for various types of integrating systems with time delay is proposed. PID parameters are given in terms of process model parameters and a tuning parameter. The tuning parameter is IMC filter time constant. In the present work, the IMC filter (Q) is chosen in such a manner that the order of the denominator of IMC controller is one less than the order of the numerator. The IMC filter time constant (λ) is tuned in such a way that a good compromise is made between performance and robustness for both servo and regulatory problems. To improve servo response of the controller a set point filter is designed such that the closed loop response is similar to that of first order plus time delay system. The proposed controller design method is applied to various transfer function models and to the non-linear model equations of jacketed CSTR to demonstrate its applicability and effectiveness. The performance of the proposed controller is compared with the recently reported methods in terms of IAE and ITAE. The smooth functioning of the controller is determined in terms of total variation and compared with recently reported methods. Simulation studies are carried out on various integrating systems with time delay to show the effectiveness and superiority of the proposed controllers.

  17. Model-based system-of-systems engineering for space-based command, control, communication, and information architecture design

    NASA Astrophysics Data System (ADS)

    Sindiy, Oleg V.

    This dissertation presents a model-based system-of-systems engineering (SoSE) approach as a design philosophy for architecting in system-of-systems (SoS) problems. SoS refers to a special class of systems in which numerous systems with operational and managerial independence interact to generate new capabilities that satisfy societal needs. Design decisions are more complicated in a SoS setting. A revised Process Model for SoSE is presented to support three phases in SoS architecting: defining the scope of the design problem, abstracting key descriptors and their interrelations in a conceptual model, and implementing computer-based simulations for architectural analyses. The Process Model enables improved decision support considering multiple SoS features and develops computational models capable of highlighting configurations of organizational, policy, financial, operational, and/or technical features. Further, processes for verification and validation of SoS models and simulations are also important due to potential impact on critical decision-making and, thus, are addressed. Two research questions frame the research efforts described in this dissertation. The first concerns how the four key sources of SoS complexity---heterogeneity of systems, connectivity structure, multi-layer interactions, and the evolutionary nature---influence the formulation of SoS models and simulations, trade space, and solution performance and structure evaluation metrics. The second question pertains to the implementation of SoSE architecting processes to inform decision-making for a subset of SoS problems concerning the design of information exchange services in space-based operations domain. These questions motivate and guide the dissertation's contributions. A formal methodology for drawing relationships within a multi-dimensional trade space, forming simulation case studies from applications of candidate architecture solutions to a campaign of notional mission use cases, and

  18. Characterization of a polyurethane-based controlled release system for local delivery of chlorhexidine diacetate.

    PubMed

    Huynh, Truc Thanh Ngoc; Padois, Karine; Sonvico, Fabio; Rossi, Alessandra; Zani, Franca; Pirot, Fabrice; Doury, Jacques; Falson, Françoise

    2010-02-01

    Conventional formulations of chlorhexidine usually provide short-term efficiency, requiring repeated applications to maintain antibacterial activity. Therefore, appropriate release system of chlorhexidine controlling local drug delivery would reduce the number of applications and enhance patient compliance. The aim of this study was to develop a controlled release system based on medical polyurethane for the local delivery of chlorhexidine diacetate (CDA). CDA-loaded polyurethane films (CDA-Films) and CDA-loaded polyurethane sandwiches (CDA-Sandwiches) were obtained by casting and solvent evaporation. The physico-chemical aspects of CDA-loaded polyurethane systems were investigated, and the crystalline state of CDA in the polymeric system was highlighted. CDA-Films exhibited appropriate mechanical properties for further applications. Drug release was measured in two different media: (i) distilled water and (ii) physiological saline solution to mimic in vivo conditions. Drug release studies were performed up to 11days on CDA-Films and 29days for CDA-Sandwiches. Release of CDA depended on drug loading and the structure of the system. In particular, release of CDA from the sandwich system followed zero-order kinetic. The release rate was significantly lower in physiological solution. Antibacterial studies were carried out on CDA-Films against Staphylococcus aureus and Staphylococcus epidermidis showing 35days persisting antibacterial activity. In conclusion, the polyurethane-based system developed in this study is potentially useful as a local delivery system for CDA and could be used not only in surgery but also in dental and clinical applications. PMID:19909814

  19. Characterization of a polyurethane-based controlled release system for local delivery of chlorhexidine diacetate.

    PubMed

    Huynh, Truc Thanh Ngoc; Padois, Karine; Sonvico, Fabio; Rossi, Alessandra; Zani, Franca; Pirot, Fabrice; Doury, Jacques; Falson, Françoise

    2010-02-01

    Conventional formulations of chlorhexidine usually provide short-term efficiency, requiring repeated applications to maintain antibacterial activity. Therefore, appropriate release system of chlorhexidine controlling local drug delivery would reduce the number of applications and enhance patient compliance. The aim of this study was to develop a controlled release system based on medical polyurethane for the local delivery of chlorhexidine diacetate (CDA). CDA-loaded polyurethane films (CDA-Films) and CDA-loaded polyurethane sandwiches (CDA-Sandwiches) were obtained by casting and solvent evaporation. The physico-chemical aspects of CDA-loaded polyurethane systems were investigated, and the crystalline state of CDA in the polymeric system was highlighted. CDA-Films exhibited appropriate mechanical properties for further applications. Drug release was measured in two different media: (i) distilled water and (ii) physiological saline solution to mimic in vivo conditions. Drug release studies were performed up to 11days on CDA-Films and 29days for CDA-Sandwiches. Release of CDA depended on drug loading and the structure of the system. In particular, release of CDA from the sandwich system followed zero-order kinetic. The release rate was significantly lower in physiological solution. Antibacterial studies were carried out on CDA-Films against Staphylococcus aureus and Staphylococcus epidermidis showing 35days persisting antibacterial activity. In conclusion, the polyurethane-based system developed in this study is potentially useful as a local delivery system for CDA and could be used not only in surgery but also in dental and clinical applications.

  20. An agent-based simulation-assisted approach to bi-lateral building systems control

    NASA Astrophysics Data System (ADS)

    Mo, Zhengchun

    Two of the primary objectives of building operations are maximizing occupancy comfort and minimizing energy costs. While research effort has been focused on concept development, design decision support and systems advancement, little attention has been paid to operational decision support. Most commercial buildings are operated under a central control scheme, in which a building operator makes control decisions without in-depth information about individual preference. Widely used set points represent generalized human requirements that do not sufficiently address individual differences. Energy costs, on the other hand, are easier to measure. As a result, operational decisions tend to favor cost savings at the expense of individual occupancy comfort. Personal control systems have enabled individual occupants to customize their local environments. It is argued that individual occupants and building operators have different motivations for environmental controls. They access to different scopes of information and represent partial knowledge for operational solutions. Such a new control environment suggests a bi-lateral control scheme that cannot be offered by existing central control schemes or distributed control schemes. There is a critical need for methods that support the bi-lateral control scheme, in which building operators and individual occupants coordinate to make balanced control decisions. Toward this end, an agent-based simulation-assisted computational framework has been proposed and prototypically implemented in the lighting controls domain. The prototype supports bi-lateral building operations by offering concurrent evaluation of alternative control strategies. The experimental results showed that, by utilizing the proposed framework, the energy use is greatly reduced without undue increase in individual visual discomfort.

  1. Control and optimization system

    DOEpatents

    Xinsheng, Lou

    2013-02-12

    A system for optimizing a power plant includes a chemical loop having an input for receiving an input parameter (270) and an output for outputting an output parameter (280), a control system operably connected to the chemical loop and having a multiple controller part (230) comprising a model-free controller. The control system receives the output parameter (280), optimizes the input parameter (270) based on the received output parameter (280), and outputs an optimized input parameter (270) to the input of the chemical loop to control a process of the chemical loop in an optimized manner.

  2. Hybrid Automaton Based Controller Design for Damage Mitigation of Islanded Power Systems

    NASA Astrophysics Data System (ADS)

    Lahiri, Sudipta

    some of these limitations, we derive a hybrid automaton model of a power system as a Discrete Event System (DES) plant and controller. The DES plant consists of a switched continuous system with an interface. The system state space is categorized based on safety criteria and discrete control specifications are embedded as transition rules within the DES controller. The DES controller searches for feasible control policies that drive the system trajectories from unsafe states to safe states. We define metrics to quantify the performance of these policies, thus allowing the derivation of the most suitable policy for a set of design specifications and disturbance type. Applications in voltage control, frequency control and dynamic service restoration is presented on a benchmark power system with approximately forty continuous states and eighteen thousand discrete states. To enable the analysis, we build a computational framework based on efficient symbolic computation tools in Mathematica and numerical integration tools in Matlab / Simulink so that the methodology can be replicated for a wide variety of applications. The framework is quite general, and may be expanded to problems beyond power systems.

  3. Bilateral control-based compensation for rotation in imaging in scan imaging systems

    NASA Astrophysics Data System (ADS)

    Tian, Dapeng; Wang, Yutang; Wang, Fuchao; Zhang, Yupeng

    2015-12-01

    Scan imaging systems rely on the rotation of a mirror to scan an image. The rotation in the resulting image must be compensated to prevent information loss. Satisfactory performance of an imaging system is difficult to achieve when employing the methods of mechanical transmission and unilateral tracking control, especially when the system suffers from nonlinear factors, disturbances, and dynamic uncertainties. This paper proposes a compensation method based on bilateral control derived from the field of haptic robots. A two-loop disturbance observer was designed to guarantee that the dynamic characteristics of the motor are close to those of the nominal model. The controllers were designed on the basis of the small gain theorem. Experiments were conducted for a comparison with the traditional unilateral control-based compensation. The comparison showed a reduction of 99.83% in the L2 norm of error, which validates the method. The proposed method improves the accuracy of compensation for rotation in imaging, and demonstrates that bilateral control has feasibility for application in various fields, including photogrammetry.

  4. Computer-based supervisory control and data acquisition system for the radioactive waste evaporator

    SciTech Connect

    Pope, N.G.; Schreiber, S.B.; Yarbro, S.L.; Gomez, B.G.; Nekimken, H.L.; Sanchez, D.E.; Bibeau, R.A.; Macdonald, J.M.

    1994-12-01

    The evaporator process at TA-55 reduces the amount of transuranic liquid radioactive waste by separating radioactive salts from relatively low-level radioactive nitric acid solution. A computer-based supervisory control and data acquisition (SCADA) system has been installed on the process that allows the operators to easily interface with process equipment. Individual single-loop controllers in the SCADA system allow more precise process operation with less human intervention. With this system, process data can be archieved in computer files for later analysis. Data are distributed throughout the TA-55 site through a local area network so that real-time process conditions can be monitored at multiple locations. The entire system has been built using commercially available hardware and software components.

  5. Host-based data acquisition system to control pulsed facilities of the accelerator

    NASA Astrophysics Data System (ADS)

    Zamriy, V. N.

    2016-09-01

    The report discusses development of the host-based system to carry out timed measurements and data acquisition for the control of pulsed facilities of the accelerator. We consider modes of timing and allocation of operations of channels and the system node. The time of any working cycle of the pulsed facilities, rate of a data flow and an amount of serviced channels are coordinated with operation characteristics of the system node. Estimations of the readout rate of the data and the waiting time demonstrate the system efficiency. The technique has been developed to provide checking of groups of pulse parameters and control the facilities of the linear accelerator of electrons LUE-200 of the neutron source IREN.

  6. A rule-based system for real-time analysis of control systems

    NASA Technical Reports Server (NTRS)

    Larson, Richard R.; Millard, D. Edward

    1992-01-01

    An approach to automate the real-time analysis of flight critical health monitoring and system status is being developed and evaluated at the NASA Dryden Flight Research Facility. A software package was developed in-house and installed as part of the extended aircraft interrogation and display system. This design features a knowledge-base structure in the form of rules to formulate interpretation and decision logic of real-time data. This technique has been applied for ground verification and validation testing and flight testing monitoring where quick, real-time, safety-of-flight decisions can be very critical. In many cases post processing and manual analysis of flight system data are not required. The processing is described of real-time data for analysis along with the output format which features a message stack display. The development, construction, and testing of the rule-driven knowledge base, along with an application using the X-31A flight test program, are presented.

  7. A WebGIS-based command control system for forest fire fighting

    NASA Astrophysics Data System (ADS)

    Yang, Jianyu; Ming, Dongping; Zhang, Xiaodong; Huang, Haitao

    2006-10-01

    Forest is a finite resource and fire prevention is crucial work. However, once a forest fire or accident occurs, timely and effective fire-fighting is the only necessary measure. The aim of this research is to build a computerized command control system based on WEBGIS to direct fire-fighting. Firstly, this paper introduces the total technique flow and functional modules of the system. Secondly, this paper analyses the key techniques for building the system, and they are data obtaining, data organizing & management, architecture of WebGIS and sharing & interoperation technique. In the end, this paper demonstrates the on line martial symbol editing function to show the running result of system. The practical application of this system showed that it played very important role in the forest fire fighting work. In addition, this paper proposes some strategic recommendations for the further development of the system.

  8. Improvement of photovoltaic pumping systems based on standard frequency converters by means of programmable logic controllers

    SciTech Connect

    Fernandez-Ramos, Jose; Narvarte-Fernandez, Luis; Poza-Saura, Fernando

    2010-01-15

    Photovoltaic pumping systems (PVPS) based on standard frequency converters (SFCs) are currently experiencing a growing interest in pumping programmes implemented in remote areas because of their high performance in terms of component reliability, low cost, high power range and good availability of components virtually anywhere in the world. However, in practical applications there have appeared a number of problems related to the adaptation of the SFCs to the requirements of the photovoltaic pumping systems (PVPS). Another disadvantage of dedicated PVPS is the difficulty in implementing maximum power point tracking (MPPT). This paper shows that these problems can be solved through the addition of a basic industrial programmable logic controller (PLC) to the system. This PLC does not increase the cost and complexity of the system, but improves the adaptation of the SFC to the photovoltaic pumping system, and increases the overall performance of the system. (author)

  9. Thermal control systems for low-temperature heat rejection on a lunar base

    NASA Technical Reports Server (NTRS)

    Sridhar, K. R.; Gottmann, Matthias

    1992-01-01

    One of the important issues in the lunar base architecture is the design of a Thermal Control System (TCS) to reject the low temperature heat from the base. The TCS ensures that the base and all components inside are maintained within the operating temperature range. A significant portion of the total mass of the TCS is due to the radiator. Shading the radiation from the sun and the hot lunar soil could decrease the radiator operating temperature significantly. Heat pumps have been in use for terrestrial applications. To optimize the mass of the heat pump augmented TCS, all promising options have to be evaluated and compared. Careful attention is given to optimizing system operating parameters, working fluids, and component masses. The systems are modeled for full load operation.

  10. The System Power Control Unit Based on the On-Chip Wireless Communication System

    PubMed Central

    Li, Tiefeng; Ma, Caiwen; Li, WenHua

    2013-01-01

    Currently, the on-chip wireless communication system (OWCS) includes 2nd-generation (2G), 3rd-generation (3G), and long-term evolution (LTE) communication subsystems. To improve the power consumption of OWCS, a typical architecture design of system power control unit (SPCU) is given in this paper, which can not only make a 2G, a 3G, and an LTE subsystems enter sleep mode, but it can also wake them up from sleep mode via the interrupt. During the sleep mode period, either the real-time sleep timer or the global system for mobile (GSM) communication sleep timer can be used individually to arouse the corresponding subsystem. Compared to previous sole voltage supplies on the OWCS, a 2G, a 3G, or an LTE subsystem can be independently configured with three different voltages and frequencies in normal work mode. In the meantime, the voltage supply monitor, which is an important part in the SPCU, can significantly guard the voltage of OWCS in real time. Finally, the SPCU may implement dynamic voltage and frequency scaling (DVFS) for a 2G, a 3G, or an LTE subsystem, which is automatically accomplished by the hardware. PMID:23818835

  11. The system power control unit based on the on-chip wireless communication system.

    PubMed

    Li, Tiefeng; Ma, Caiwen; Li, WenHua

    2013-01-01

    Currently, the on-chip wireless communication system (OWCS) includes 2nd-generation (2G), 3rd-generation (3G), and long-term evolution (LTE) communication subsystems. To improve the power consumption of OWCS, a typical architecture design of system power control unit (SPCU) is given in this paper, which can not only make a 2G, a 3G, and an LTE subsystems enter sleep mode, but it can also wake them up from sleep mode via the interrupt. During the sleep mode period, either the real-time sleep timer or the global system for mobile (GSM) communication sleep timer can be used individually to arouse the corresponding subsystem. Compared to previous sole voltage supplies on the OWCS, a 2G, a 3G, or an LTE subsystem can be independently configured with three different voltages and frequencies in normal work mode. In the meantime, the voltage supply monitor, which is an important part in the SPCU, can significantly guard the voltage of OWCS in real time. Finally, the SPCU may implement dynamic voltage and frequency scaling (DVFS) for a 2G, a 3G, or an LTE subsystem, which is automatically accomplished by the hardware.

  12. The system power control unit based on the on-chip wireless communication system.

    PubMed

    Li, Tiefeng; Ma, Caiwen; Li, WenHua

    2013-01-01

    Currently, the on-chip wireless communication system (OWCS) includes 2nd-generation (2G), 3rd-generation (3G), and long-term evolution (LTE) communication subsystems. To improve the power consumption of OWCS, a typical architecture design of system power control unit (SPCU) is given in this paper, which can not only make a 2G, a 3G, and an LTE subsystems enter sleep mode, but it can also wake them up from sleep mode via the interrupt. During the sleep mode period, either the real-time sleep timer or the global system for mobile (GSM) communication sleep timer can be used individually to arouse the corresponding subsystem. Compared to previous sole voltage supplies on the OWCS, a 2G, a 3G, or an LTE subsystem can be independently configured with three different voltages and frequencies in normal work mode. In the meantime, the voltage supply monitor, which is an important part in the SPCU, can significantly guard the voltage of OWCS in real time. Finally, the SPCU may implement dynamic voltage and frequency scaling (DVFS) for a 2G, a 3G, or an LTE subsystem, which is automatically accomplished by the hardware. PMID:23818835

  13. Active control of a flexible smart beam using a system identification technique based on ARMAX

    NASA Astrophysics Data System (ADS)

    Bu, Xiongzhu; Ye, Lin; Su, Zhongqing; Wang, Chunhui

    2003-10-01

    A study on active vibration suppression for a flexible structural beam via a system identification approach was experimentally performed. The beam, incorporating a pair of piezoceramic transducers as actuators and a set of surface-bonded strain gauges as sensors, was evaluated. The relationship between the input control voltage applied on the actuators and the consequently induced strain, measured by the sensor, was then derived. An active control system, considering both the actuators and sensor, was configured using the ARMAX (auto-regressive moving average exogenous) model. A continuous signal with step waveform was selected as the input excitation. A digital-signal-processor-based real-time adaptive vibration control algorithm, supported by Agilent® E1415A, SCPs 1511 and SCPs 1532, was developed, and an algorithm was established using a pole placement control method, so as to achieve the desired closed-loop control. The effectiveness of the ARMAX model was examined by comparing it with the ARX (auto-regression with extra inputs) model. The results show good performance of the ARMAX model for system identification purposes and excellent effectiveness for active structural vibration control.

  14. Advanced piloted aircraft flight control system design methodology. Volume 1: Knowledge base

    NASA Technical Reports Server (NTRS)

    Mcruer, Duane T.; Myers, Thomas T.

    1988-01-01

    The development of a comprehensive and electric methodology for conceptual and preliminary design of flight control systems is presented and illustrated. The methodology is focused on the design stages starting with the layout of system requirements and ending when some viable competing system architectures (feedback control structures) are defined. The approach is centered on the human pilot and the aircraft as both the sources of, and the keys to the solution of, many flight control problems. The methodology relies heavily on computational procedures which are highly interactive with the design engineer. To maximize effectiveness, these techniques, as selected and modified to be used together in the methodology, form a cadre of computational tools specifically tailored for integrated flight control system preliminary design purposes. While theory and associated computational means are an important aspect of the design methodology, the lore, knowledge and experience elements, which guide and govern applications are critical features. This material is presented as summary tables, outlines, recipes, empirical data, lists, etc., which encapsulate a great deal of expert knowledge. Much of this is presented in topical knowledge summaries which are attached as Supplements. The composite of the supplements and the main body elements constitutes a first cut at a a Mark 1 Knowledge Base for manned-aircraft flight control.

  15. Bonding surgical incisions using a temperature-controlled laser system based on a single infrared fiber.

    PubMed

    Gabay, Ilan; Barequet, Irina; Varssano, David; Rosner, Mordechai; Katzir, Abraham

    2013-11-01

    ABSTRACT. Although there has been great interest in laser heating for bonding of surgical incisions in tissues, it has not gained wide acceptance by surgeons. We argue that the main obstacle has been the lack of temperature control, which may lead to a weak bonding. We previously developed a laser bonding system based on two infrared transmitting AgBrCl fibers, one for laser heating and one for temperature control. In view of the inherent limitations of such systems observed in many animal experiments, we developed an improved system based on a single infrared fiber. Besides the decreased dimensions, this system offers many advantages over the two-fiber system. It is less sensitive to accuracy of height and tilt of the fiber distal tip above the tissue, ensuring more accurate heating that can potentially lead to stronger bonding with minimal thermal damage. The system is successfully tested in the soldering of 15 corneal incisions, ex vivo. Histopathology shows little thermal damage and good wound apposition. The average burst pressure is 100±30  mm Hg. These findings indicate the usefulness of the system for ophthalmic surgery as well as other surgical procedures, including endoscopic and robotic surgery.

  16. Lyapunov-based control of limit cycle oscillations in uncertain aircraft systems

    NASA Astrophysics Data System (ADS)

    Bialy, Brendan

    Store-induced limit cycle oscillations (LCO) affect several fighter aircraft and is expected to remain an issue for next generation fighters. LCO arises from the interaction of aerodynamic and structural forces, however the primary contributor to the phenomenon is still unclear. The practical concerns regarding this phenomenon include whether or not ordnance can be safely released and the ability of the aircrew to perform mission-related tasks while in an LCO condition. The focus of this dissertation is the development of control strategies to suppress LCO in aircraft systems. The first contribution of this work (Chapter 2) is the development of a controller consisting of a continuous Robust Integral of the Sign of the Error (RISE) feedback term with a neural network (NN) feedforward term to suppress LCO behavior in an uncertain airfoil system. The second contribution of this work (Chapter 3) is the extension of the development in Chapter 2 to include actuator saturation. Suppression of LCO behavior is achieved through the implementation of an auxiliary error system that features hyperbolic functions and a saturated RISE feedback control structure. Due to the lack of clarity regarding the driving mechanism behind LCO, common practice in literature and in Chapters 2 and 3 is to replicate the symptoms of LCO by including nonlinearities in the wing structure, typically a nonlinear torsional stiffness. To improve the accuracy of the system model a partial differential equation (PDE) model of a flexible wing is derived (see Appendix F) using Hamilton's principle. Chapters 4 and 5 are focused on developing boundary control strategies for regulating the bending and twisting deformations of the derived model. The contribution of Chapter 4 is the construction of a backstepping-based boundary control strategy for a linear PDE model of an aircraft wing. The backstepping-based strategy transforms the original system to a exponentially stable system. A Lyapunov-based stability

  17. Data-based fault-tolerant control for affine nonlinear systems with actuator faults.

    PubMed

    Xie, Chun-Hua; Yang, Guang-Hong

    2016-09-01

    This paper investigates the fault-tolerant control (FTC) problem for unknown nonlinear systems with actuator faults including stuck, outage, bias and loss of effectiveness. The upper bounds of stuck faults, bias faults and loss of effectiveness faults are unknown. A new data-based FTC scheme is proposed. It consists of the online estimations of the bounds and a state-dependent function. The estimations are adjusted online to compensate automatically the actuator faults. The state-dependent function solved by using real system data helps to stabilize the system. Furthermore, all signals in the resulting closed-loop system are uniformly bounded and the states converge asymptotically to zero. Compared with the existing results, the proposed approach is data-based. Finally, two simulation examples are provided to show the effectiveness of the proposed approach. PMID:27180025

  18. Modeling, control, and dispatch of photovoltaic-based power distribution systems

    NASA Astrophysics Data System (ADS)

    Carrasco, Miguel

    Small-scale generators, also called distributed generators (DGs), are primed to play a central role in future distribution systems. If properly integrated, DGs present two main advantages: (i) they help decongest existing transmission grids; and (ii) CO2 emissions are reduced since most DGs are based on renewables like wind and solar. Their integration into distribution systems is one of the main challenges the power industry will be facing in the coming years. Photovoltaic (PV) power generation represents a key technology for realizing the DG concept. In this dissertation, technical solutions are developed that enable an increased penetration of PV systems, while improving the efficiency, reliability, and power quality of power distribution grids. The presented research spans from PV array modeling, parameter identification and estimation methods, through advanced control strategies for the power electronic interfaces, to system--level optimal dispatch strategies. Simulation-based and experimental validation results show the performance of the proposed techniques.

  19. Wireless Sensor Network-Based Greenhouse Environment Monitoring and Automatic Control System for Dew Condensation Prevention

    PubMed Central

    Park, Dae-Heon; Park, Jang-Woo

    2011-01-01

    Dew condensation on the leaf surface of greenhouse crops can promote diseases caused by fungus and bacteria, affecting the growth of the crops. In this paper, we present a WSN (Wireless Sensor Network)-based automatic monitoring system to prevent dew condensation in a greenhouse environment. The system is composed of sensor nodes for collecting data, base nodes for processing collected data, relay nodes for driving devices for adjusting the environment inside greenhouse and an environment server for data storage and processing. Using the Barenbrug formula for calculating the dew point on the leaves, this system is realized to prevent dew condensation phenomena on the crop’s surface acting as an important element for prevention of diseases infections. We also constructed a physical model resembling the typical greenhouse in order to verify the performance of our system with regard to dew condensation control. PMID:22163813

  20. An arc control and protection system for the JET lower hybrid antenna based on an imaging system

    NASA Astrophysics Data System (ADS)

    Figueiredo, J.; Mailloux, J.; Kirov, K.; Kinna, D.; Stamp, M.; Devaux, S.; Arnoux, G.; Edwards, J. S.; Stephen, A. V.; McCullen, P.; Hogben, C.

    2014-11-01

    Arcs are the potentially most dangerous events related to Lower Hybrid (LH) antenna operation. If left uncontrolled they can produce damage and cause plasma disruption by impurity influx. To address this issue an arc real time control and protection imaging system for the Joint European Torus (JET) LH antenna has been implemented. The LH system is one of the additional heating systems at JET. It comprises 24 microwave generators (klystrons, operating at 3.7 GHz) providing up to 5 MW of heating and current drive to the JET plasma. This is done through an antenna composed of an array of waveguides facing the plasma. The protection system presented here is based primarily on an imaging arc detection and real time control system. It has adapted the ITER like wall hotspot protection system using an identical CCD camera and real time image processing unit. A filter has been installed to avoid saturation and spurious system triggers caused by ionization light. The antenna is divided in 24 Regions Of Interest (ROIs) each one corresponding to one klystron. If an arc precursor is detected in a ROI, power is reduced locally with subsequent potential damage and plasma disruption avoided. The power is subsequently reinstated if, during a defined interval of time, arcing is confirmed not to be present by image analysis. This system was successfully commissioned during the restart phase and beginning of the 2013 scientific campaign. Since its installation and commissioning, arcs and related phenomena have been prevented. In this contribution we briefly describe the camera, image processing, and real time control systems. Most importantly, we demonstrate that an LH antenna arc protection system based on CCD camera imaging systems works. Examples of both controlled and uncontrolled LH arc events and their consequences are shown.

  1. An arc control and protection system for the JET lower hybrid antenna based on an imaging system.

    PubMed

    Figueiredo, J; Mailloux, J; Kirov, K; Kinna, D; Stamp, M; Devaux, S; Arnoux, G; Edwards, J S; Stephen, A V; McCullen, P; Hogben, C

    2014-11-01

    Arcs are the potentially most dangerous events related to Lower Hybrid (LH) antenna operation. If left uncontrolled they can produce damage and cause plasma disruption by impurity influx. To address this issue an arc real time control and protection imaging system for the Joint European Torus (JET) LH antenna has been implemented. The LH system is one of the additional heating systems at JET. It comprises 24 microwave generators (klystrons, operating at 3.7 GHz) providing up to 5 MW of heating and current drive to the JET plasma. This is done through an antenna composed of an array of waveguides facing the plasma. The protection system presented here is based primarily on an imaging arc detection and real time control system. It has adapted the ITER like wall hotspot protection system using an identical CCD camera and real time image processing unit. A filter has been installed to avoid saturation and spurious system triggers caused by ionization light. The antenna is divided in 24 Regions Of Interest (ROIs) each one corresponding to one klystron. If an arc precursor is detected in a ROI, power is reduced locally with subsequent potential damage and plasma disruption avoided. The power is subsequently reinstated if, during a defined interval of time, arcing is confirmed not to be present by image analysis. This system was successfully commissioned during the restart phase and beginning of the 2013 scientific campaign. Since its installation and commissioning, arcs and related phenomena have been prevented. In this contribution we briefly describe the camera, image processing, and real time control systems. Most importantly, we demonstrate that an LH antenna arc protection system based on CCD camera imaging systems works. Examples of both controlled and uncontrolled LH arc events and their consequences are shown.

  2. An arc control and protection system for the JET lower hybrid antenna based on an imaging system

    SciTech Connect

    Figueiredo, J.

    2014-11-15

    Arcs are the potentially most dangerous events related to Lower Hybrid (LH) antenna operation. If left uncontrolled they can produce damage and cause plasma disruption by impurity influx. To address this issue an arc real time control and protection imaging system for the Joint European Torus (JET) LH antenna has been implemented. The LH system is one of the additional heating systems at JET. It comprises 24 microwave generators (klystrons, operating at 3.7 GHz) providing up to 5 MW of heating and current drive to the JET plasma. This is done through an antenna composed of an array of waveguides facing the plasma. The protection system presented here is based primarily on an imaging arc detection and real time control system. It has adapted the ITER like wall hotspot protection system using an identical CCD camera and real time image processing unit. A filter has been installed to avoid saturation and spurious system triggers caused by ionization light. The antenna is divided in 24 Regions Of Interest (ROIs) each one corresponding to one klystron. If an arc precursor is detected in a ROI, power is reduced locally with subsequent potential damage and plasma disruption avoided. The power is subsequently reinstated if, during a defined interval of time, arcing is confirmed not to be present by image analysis. This system was successfully commissioned during the restart phase and beginning of the 2013 scientific campaign. Since its installation and commissioning, arcs and related phenomena have been prevented. In this contribution we briefly describe the camera, image processing, and real time control systems. Most importantly, we demonstrate that an LH antenna arc protection system based on CCD camera imaging systems works. Examples of both controlled and uncontrolled LH arc events and their consequences are shown.

  3. Hierarchical flight control system synthesis for rotorcraft-based unmanned aerial vehicles

    NASA Astrophysics Data System (ADS)

    Shim, Hyunchul

    The Berkeley Unmanned Aerial Vehicle (UAV) research aims to design, implement, and analyze a group of autonomous intelligent UAVs and UGVs (Unmanned Ground Vehicles). The goal of this dissertation is to provide a comprehensive procedural methodology to design, implement, and test rotorcraft-based unmanned aerial vehicles (RUAVs). We choose the rotorcraft as the base platform for our aerial agents because it offers ideal maneuverability for our target scenarios such as the pursuit-evasion game. Aided by many enabling technologies such as lightweight and powerful computers, high-accuracy navigation sensors and communication devices, it is now possible to construct RUAVs capable of precise navigation and intelligent behavior by the decentralized onboard control system. Building a fully functioning RUAV requires a deep understanding of aeronautics, control theory and computer science as well as a tremendous effort for implementation. These two aspects are often inseparable and therefore equally highlighted throughout this research. The problem of multiple vehicle coordination is approached through the notion of a hierarchical system. The idea behind the proposed architecture is to build a hierarchical multiple-layer system that gradually decomposes the abstract mission objectives into the physical quantities of control input. Each RUAV incorporated into this system performs the given tasks and reports the results through the hierarchical communication channel back to the higher-level coordinator. In our research, we provide a theoretical and practical approach to build a number of RUAVs based on commercially available navigation sensors, computer systems, and radio-controlled helicopters. For the controller design, the dynamic model of the helicopter is first built. The helicopter exhibits a very complicated multi-input multi-output, nonlinear, time-varying and coupled dynamics, which is exposed to severe exogenous disturbances. This poses considerable difficulties for

  4. A microprocessor-based position control system for a telescope secondary mirror

    NASA Technical Reports Server (NTRS)

    Lorell, K. R.; Barrows, W. F.; Clappier, R. R.; Lee, G. K.

    1983-01-01

    The pointing requirements for the Shuttle IR Telescope Facility (SIRTF), which consists of an 0.85-m cryogenically cooled IR telescope, call for an image stability of 0.25 arcsec. Attention is presently given to a microprocessor-based position control system developed for the control of the SIRTF secondary mirror, employing a special control law (to minimize energy dissipation), a precision capacitive position sensor, and a specially designed power amplifier/actuator combination. The microprocessor generates the command angular position and rate waveforms in order to maintain a 90 percent dwell time/10 percent transition time ratio independently of chop frequency or amplitude. Performance and test results of a prototype system designed for use with a demonstration model of the SIRTF focal plane fine guidance sensor are presented.

  5. A P300-based BCI system for controlling computer cursor movement.

    PubMed

    Kanoh, S; Miyamoto, K; Yoshinobu, T

    2011-01-01

    A P300-based BCI (brain-computer interface) system for controlling the movement of the cursor displayed on the computer screen was proposed and evaluated. On the LCD computer screen, the cursor was displayed with the surrounded eight small circles, each of which was blinked sequentially in a random order. Five healthy subjects were requested to gaze at one of the circles placed in the preferred direction. The P300 activities elicited by the random blink of the target circle were detected by pattern classifier and they were used to move the cursor to the same direction as the target circle. It was shown that all of the subjects could control the movement of the cursor to their preferred direction by moving their gaze point in a short distance. This system can be applied to the voluntary control of the movement of the computer cursor, and the navigation of robot or video camera, without using users' extremities.

  6. A contention-based bus-control scheme for multiprocessor systems

    NASA Technical Reports Server (NTRS)

    Juang, Jie-Yong; Wah, Benjamin W.

    1991-01-01

    The authors study contention-based bus-control schemes for scheduling processors in using a bit-parallel shared bus. The protocol is designed under the requirements that each processor exhibit a random access behavior, that there be no centralized bus control in the system, and that access be granted in real time. The proposed scheme is based on splitting algorithms used in conventional contention-resolution schemes, and utilizes two-state information obtained from collision detection. Two versions of the bus-control scheme are studied. The static one resolves contentions of N requesting processors in an average of O(logW/2N) iterations, where W is the number of bits in the bit-parallel bus. An adaptive version resolves contentions in an average time that is independent of N.

  7. Investigation and Improvement of Torque Response of Control System Based on Direct Torque Control in Interior Permanent Magnet Synchronous Motors

    NASA Astrophysics Data System (ADS)

    Inoue, Yukinori; Morimoto, Shigeo; Sanada, Masayuki

    In this study, we investigate the torque response of a control system that is based on the direct torque control (DTC) principle for an interior permanent magnet synchronous motor (IPMSM). We also propose a gain-scheduling method for improving the torque response. Reference flux vector calculation (RFVC) DTC is used in this study. In RFVC DTC, a PI controller is used for torque control; this is in contrast to the use of the hysteresis comparator and switching table in basic DTC. In this paper, we present the relationship between the torque response and the gain of the PI controller. This relationship is derived by using the transfer function of the torque control loop. In this study, we also examine the difference between the torque responses of two motors that have different machine parameters. The proposed method can be used to realize a torque response that is independent of the operating torque. The simulation results and experimental results presented in this paper show the validity of the derived relationship as well as the effectiveness of the proposed method.

  8. Observer-based approximate optimal tracking control for time-delay systems with external disturbances

    NASA Astrophysics Data System (ADS)

    Su, Hao; Tang, Gong-You

    2016-09-01

    This paper proposes a successive approximation design approach of observer-based optimal tracking controllers for time-delay systems with external disturbances. To solve a two-point boundary value problem with time-delay and time-advance terms and obtain the optimal tracking control law, two sequences of vector differential equations are constructed first. Second, the convergence of the sequences of the vector differential equations is proved to guarantee the existence and uniqueness of the control law. Third, a design algorithm of the optimal tracking control law is presented and the physically realisable problem is addressed by designing a disturbance state observer and a reference input state observer. An example of an industrial electric heater is given to demonstrate the efficiency of the proposed approach.

  9. Design of Control System for Flexible Packaging Bags Palletizing Production Line Based on PLC

    NASA Astrophysics Data System (ADS)

    Zheng, Huiping; Chen, Lin; Zhao, Xiaoming; Liu, Zhanyang

    Flexible packaging bags palletizing production line is to put the bags in the required area according to particular order and size, in order to finish handling, storage, loading and unloading, transportation and other logistics work of goods. Flexible packaging bags palletizing line is composed of turning bags mechanism, shaping mechanism, indexing mechanism, marshalling mechanism, pushing bags mechanism, pressing bags mechanism, laminating mechanism, elevator, tray warehouse, tray conveyor and loaded tray conveyor. Whether the whole production line can smoothly run depends on each of the above equipment and precision control among them. In this paper the technological process and the control logic of flexible packaging bags palletizing production line is introduced. Palletizing process of the production line realized automation by means of a control system based on programmable logic controller (PLC). It has the advantages of simple structure, reliable and easy maintenance etc.

  10. Design of Intelligent Hydraulic Excavator Control System Based on PID Method

    NASA Astrophysics Data System (ADS)

    Zhang, Jun; Jiao, Shengjie; Liao, Xiaoming; Yin, Penglong; Wang, Yulin; Si, Kuimao; Zhang, Yi; Gu, Hairong

    Most of the domestic designed hydraulic excavators adopt the constant power design method and set 85%~90% of engine power as the hydraulic system adoption power, it causes high energy loss due to mismatching of power between the engine and the pump. While the variation of the rotational speed of engine could sense the power shift of the load, it provides a new method to adjust the power matching between engine and pump through engine speed. Based on negative flux hydraulic system, an intelligent hydraulic excavator control system was designed based on rotational speed sensing method to improve energy efficiency. The control system was consisted of engine control module, pump power adjusted module, engine idle module and system fault diagnosis module. Special PLC with CAN bus was used to acquired the sensors and adjusts the pump absorption power according to load variation. Four energy saving control strategies with constant power method were employed to improve the fuel utilization. Three power modes (H, S and L mode) were designed to meet different working status; Auto idle function was employed to save energy through two work status detected pressure switches, 1300rpm was setting as the idle speed according to the engine consumption fuel curve. Transient overload function was designed for deep digging within short time without spending extra fuel. An increasing PID method was employed to realize power matching between engine and pump, the rotational speed's variation was taken as the PID algorithm's input; the current of proportional valve of variable displacement pump was the PID's output. The result indicated that the auto idle could decrease fuel consumption by 33.33% compared to work in maximum speed of H mode, the PID control method could take full use of maximum engine power at each power mode and keep the engine speed at stable range. Application of rotational speed sensing method provides a reliable method to improve the excavator's energy efficiency and

  11. Control of MEMS-based actuator array for micro smart systems

    NASA Astrophysics Data System (ADS)

    Chapuis, Yves-Andre; Fukuta, Yamato; Zhou, Lingfei; Mita, Yoshio; Fujita, Hiroyuki

    2005-02-01

    In the present work, the authors were focused on control modes used in distributed microsystems. Especially, they studied distributed manipulation like motion active surface that have been an important topic in micro and nanofabrication field. After comparing advantages and drawbacks between centralized, decentralized and distributed control systems, they decided to apply the control mode to an airflow active surface based on pneumatic microactuator array, and fabricated by MEMS technology. The size of the device is about 35x35 mm2 for 560 MEMS-based actuators and holes respectively at the front- and the back-side of the silicon substrate. In a first approach, and to overcome fabrication problems of the micro-smart system, combining electronic and electro mechanic elements, a co-design software/hardware solution was implemented. By this way, and using a digital image captured from a CCD camera, autonomy of the distributed microsystems could be developed. Afterward, a feedback control strategy was elaborated by applying principles of autonomous mobile robots that lend it to. A first prototype, validating all control mode principles was successfully implemented directly in software. Experiment results demonstrated advantages and good performances of the method.

  12. Selected Flight Test Results for Online Learning Neural Network-Based Flight Control System

    NASA Technical Reports Server (NTRS)

    Williams, Peggy S.

    2004-01-01

    The NASA F-15 Intelligent Flight Control System project team has developed a series of flight control concepts designed to demonstrate the benefits of a neural network-based adaptive controller. The objective of the team is to develop and flight-test control systems that use neural network technology to optimize the performance of the aircraft under nominal conditions as well as stabilize the aircraft under failure conditions. Failure conditions include locked or failed control surfaces as well as unforeseen damage that might occur to the aircraft in flight. This report presents flight-test results for an adaptive controller using stability and control derivative values from an online learning neural network. A dynamic cell structure neural network is used in conjunction with a real-time parameter identification algorithm to estimate aerodynamic stability and control derivative increments to the baseline aerodynamic derivatives in flight. This set of open-loop flight tests was performed in preparation for a future phase of flights in which the learning neural network and parameter identification algorithm output would provide the flight controller with aerodynamic stability and control derivative updates in near real time. Two flight maneuvers are analyzed a pitch frequency sweep and an automated flight-test maneuver designed to optimally excite the parameter identification algorithm in all axes. Frequency responses generated from flight data are compared to those obtained from nonlinear simulation runs. An examination of flight data shows that addition of the flight-identified aerodynamic derivative increments into the simulation improved the pitch handling qualities of the aircraft.

  13. Secure UNIX socket-based controlling system for high-throughput protein crystallography experiments.

    PubMed

    Gaponov, Yurii; Igarashi, Noriyuki; Hiraki, Masahiko; Sasajima, Kumiko; Matsugaki, Naohiro; Suzuki, Mamoru; Kosuge, Takashi; Wakatsuki, Soichi

    2004-01-01

    A control system for high-throughput protein crystallography experiments has been developed based on a multilevel secure (SSL v2/v3) UNIX socket under the Linux operating system. Main features of protein crystallography experiments (purification, crystallization, loop preparation, data collecting, data processing) are dealt with by the software. All information necessary to perform protein crystallography experiments is stored (except raw X-ray data, that are stored in Network File Server) in a relational database (MySQL). The system consists of several servers and clients. TCP/IP secure UNIX sockets with four predefined behaviors [(a) listening to a request followed by a reply, (b) sending a request and waiting for a reply, (c) listening to a broadcast message, and (d) sending a broadcast message] support communications between all servers and clients allowing one to control experiments, view data, edit experimental conditions and perform data processing remotely. The usage of the interface software is well suited for developing well organized control software with a hierarchical structure of different software units (Gaponov et al., 1998), which will pass and receive different types of information. All communication is divided into two parts: low and top levels. Large and complicated control tasks are split into several smaller ones, which can be processed by control clients independently. For communicating with experimental equipment (beamline optical elements, robots, and specialized experimental equipment etc.), the STARS server, developed at the Photon Factory, is used (Kosuge et al., 2002). The STARS server allows any application with an open socket to be connected with any other clients that control experimental equipment. Majority of the source code is written in C/C++. GUI modules of the system were built mainly using Glade user interface builder for GTK+ and Gnome under Red Hat Linux 7.1 operating system.

  14. A novel BCI-controlled pneumatic glove system for home-based neurorehabilitation.

    PubMed

    Coffey, Aodhán L; Leamy, Darren J; Ward, Tomás E

    2014-01-01

    Commercially available devices for Brain-Computer Interface (BCI)-controlled robotic stroke rehabilitation are prohibitively expensive for many researchers who are interested in the topic and physicians who would utilize such a device. Additionally, they are cumbersome and require a technician to operate, increasing the inaccessibility of such devices for home-based robotic stroke rehabilitation therapy. Presented here is the design, implementation and test of an inexpensive, portable and adaptable BCI-controlled hand therapy device. The system utilizes a soft, flexible, pneumatic glove which can be used to deflect the subject's wrist and fingers. Operation is provided by a custom-designed pneumatic circuit. Air flow is controlled by an embedded system, which receives serial port instruction from a PC running real-time BCI software. System tests demonstrate that glove control can be successfully driven by a real-time BCI. A system such as the one described here may be used to explore closed loop neurofeedback rehabilitation in stroke relatively inexpensively and potentially in home environments.

  15. A Thermal Expert System (TEXSYS) development overview - AI-based control of a Space Station prototype thermal bus

    NASA Technical Reports Server (NTRS)

    Glass, B. J.; Hack, E. C.

    1990-01-01

    A knowledge-based control system for real-time control and fault detection, isolation and recovery (FDIR) of a prototype two-phase Space Station Freedom external thermal control system (TCS) is discussed in this paper. The Thermal Expert System (TEXSYS) has been demonstrated in recent tests to be capable of both fault anticipation and detection and real-time control of the thermal bus. Performance requirements were achieved by using a symbolic control approach, layering model-based expert system software on a conventional numerical data acquisition and control system. The model-based capabilities of TEXSYS were shown to be advantageous during software development and testing. One representative example is given from on-line TCS tests of TEXSYS. The integration and testing of TEXSYS with a live TCS testbed provides some insight on the use of formal software design, development and documentation methodologies to qualify knowledge-based systems for on-line or flight applications.

  16. A petrolatum based system for control of external corrosion in, on and around cooling towers

    SciTech Connect

    Berry, M.A.; Steely, C.N.

    1986-01-01

    While it is true that the initial cost of a petroleum based system may be slightly higher than that of paint, this article maintains that the cost can be amortized over a 12 or 15-year period, or in some cases even longer. In service maintenance costs on a square foot per year basis, compared to all other alternatives are minimal. Petrolatum systems for external corrosion control on and around cooling towers have been effective service for over fifteen years, in diversified industrial environments that include oil refineries, chemical process plants, power utilities, hospital and university complexes and steel mills.

  17. The Chimera II Real-Time Operating System for advanced sensor-based control applications

    NASA Technical Reports Server (NTRS)

    Stewart, David B.; Schmitz, Donald E.; Khosla, Pradeep K.

    1992-01-01

    Attention is given to the Chimera II Real-Time Operating System, which has been developed for advanced sensor-based control applications. The Chimera II provides a high-performance real-time kernel and a variety of IPC features. The hardware platform required to run Chimera II consists of commercially available hardware, and allows custom hardware to be easily integrated. The design allows it to be used with almost any type of VMEbus-based processors and devices. It allows radially differing hardware to be programmed using a common system, thus providing a first and necessary step towards the standardization of reconfigurable systems that results in a reduction of development time and cost.

  18. Navigation technique for MR-endoscope system using a wireless accelerometer-based remote control device.

    PubMed

    Kumamoto, Etsuko; Takahashi, Akihiro; Matsuoka, Yuichiro; Morita, Yoshinori; Kutsumi, Hiromu; Azuma, Takeshi; Kuroda, Kagayaki

    2013-01-01

    The MR-endoscope system can perform magnetic resonance (MR) imaging during endoscopy and show the images obtained by using endoscope and MR. The MR-endoscope system can acquire a high-spatial resolution MR image with an intraluminal radiofrequency (RF) coil, and the navigation system shows the scope's location and orientation inside the human body and indicates MR images with a scope view. In order to conveniently perform an endoscopy and MR procedure, the design of the user interface is very important because it provides useful information. In this study, we propose a navigation system using a wireless accelerometer-based controller with Bluetooth technology and a navigation technique to set the intraluminal RF coil using the navigation system. The feasibility of using this wireless controller in the MR shield room was validated via phantom examinations of the influence on MR procedures and navigation accuracy. In vitro examinations using an isolated porcine stomach demonstrated the effectiveness of the navigation technique using a wireless remote-control device.

  19. CNEOST Control Software System

    NASA Astrophysics Data System (ADS)

    Wang, Xin; Zhao, Hai-bin; Xia, Yan; Lu, Hao; Li, Bin

    2016-01-01

    In 2013, CNEOST (China Near Earth Object Survey Telescope) adapted its hardware system for the new CCD camera. Based on the new system architecture, the control software is re-designed and implemented. The software system adopts the messaging mechanism based on the WebSocket protocol, and possesses good flexibility and expansibility. The user interface based on the responsive web design has realized the remote observations under both desktop and mobile devices. The stable operation of the software system has greatly enhanced the operation efficiency while reducing the complexity, and has also made a successful attempt for the future system design of telescope and telescope cloud.

  20. Self-Adaptive Strategy Based on Fuzzy Control Systems for Improving Performance in Wireless Sensors Networks.

    PubMed

    Hernández Díaz, Vicente; Martínez, José-Fernán; Lucas Martínez, Néstor; del Toro, Raúl M

    2015-09-18

    The solutions to cope with new challenges that societies have to face nowadays involve providing smarter daily systems. To achieve this, technology has to evolve and leverage physical systems automatic interactions, with less human intervention. Technological paradigms like Internet of Things (IoT) and Cyber-Physical Systems (CPS) are providing reference models, architectures, approaches and tools that are to support cross-domain solutions. Thus, CPS based solutions will be applied in different application domains like e-Health, Smart Grid, Smart Transportation and so on, to assure the expected response from a complex system that relies on the smooth interaction and cooperation of diverse networked physical systems. The Wireless Sensors Networks (WSN) are a well-known wireless technology that are part of large CPS. The WSN aims at monitoring a physical system, object, (e.g., the environmental condition of a cargo container), and relaying data to the targeted processing element. The WSN communication reliability, as well as a restrained energy consumption, are expected features in a WSN. This paper shows the results obtained in a real WSN deployment, based on SunSPOT nodes, which carries out a fuzzy based control strategy to improve energy consumption while keeping communication reliability and computational resources usage among boundaries.

  1. Self-Adaptive Strategy Based on Fuzzy Control Systems for Improving Performance in Wireless Sensors Networks

    PubMed Central

    Hernández Díaz, Vicente; Martínez, José-Fernán; Lucas Martínez, Néstor; del Toro, Raúl M.

    2015-01-01

    The solutions to cope with new challenges that societies have to face nowadays involve providing smarter daily systems. To achieve this, technology has to evolve and leverage physical systems automatic interactions, with less human intervention. Technological paradigms like Internet of Things (IoT) and Cyber-Physical Systems (CPS) are providing reference models, architectures, approaches and tools that are to support cross-domain solutions. Thus, CPS based solutions will be applied in different application domains like e-Health, Smart Grid, Smart Transportation and so on, to assure the expected response from a complex system that relies on the smooth interaction and cooperation of diverse networked physical systems. The Wireless Sensors Networks (WSN) are a well-known wireless technology that are part of large CPS. The WSN aims at monitoring a physical system, object, (e.g., the environmental condition of a cargo container), and relaying data to the targeted processing element. The WSN communication reliability, as well as a restrained energy consumption, are expected features in a WSN. This paper shows the results obtained in a real WSN deployment, based on SunSPOT nodes, which carries out a fuzzy based control strategy to improve energy consumption while keeping communication reliability and computational resources usage among boundaries. PMID:26393612

  2. Self-Adaptive Strategy Based on Fuzzy Control Systems for Improving Performance in Wireless Sensors Networks.

    PubMed

    Hernández Díaz, Vicente; Martínez, José-Fernán; Lucas Martínez, Néstor; del Toro, Raúl M

    2015-01-01

    The solutions to cope with new challenges that societies have to face nowadays involve providing smarter daily systems. To achieve this, technology has to evolve and leverage physical systems automatic interactions, with less human intervention. Technological paradigms like Internet of Things (IoT) and Cyber-Physical Systems (CPS) are providing reference models, architectures, approaches and tools that are to support cross-domain solutions. Thus, CPS based solutions will be applied in different application domains like e-Health, Smart Grid, Smart Transportation and so on, to assure the expected response from a complex system that relies on the smooth interaction and cooperation of diverse networked physical systems. The Wireless Sensors Networks (WSN) are a well-known wireless technology that are part of large CPS. The WSN aims at monitoring a physical system, object, (e.g., the environmental condition of a cargo container), and relaying data to the targeted processing element. The WSN communication reliability, as well as a restrained energy consumption, are expected features in a WSN. This paper shows the results obtained in a real WSN deployment, based on SunSPOT nodes, which carries out a fuzzy based control strategy to improve energy consumption while keeping communication reliability and computational resources usage among boundaries. PMID:26393612

  3. FORPS: a FORTH-based production system and its application to a real-time robot control problem

    SciTech Connect

    Matheus, C.J.; Martin, H.L.

    1986-01-01

    A simple yet very powerful system has been developed that merges the artificial intelligence qualities of a production system with the real-time control capabilities of FORTH. FORPS (FORTH-based Production System) offers the advantages of intelligent, rule-based control in a small package offering high speed, extensibility, and simplicity. A practical example of the system is presented in the development of an obstacle avoidance program to aid in controlling an overhead manipulator transport system. Several other potential applications to the area of control are discussed.

  4. Active control of an innovative seat suspension system with acceleration measurement based friction estimation

    NASA Astrophysics Data System (ADS)

    Ning, Donghong; Sun, Shuaishuai; Li, Hongyi; Du, Haiping; Li, Weihua

    2016-12-01

    In this paper, an innovative active seat suspension system for vehicles is presented. This seat suspension prototype is built with two low cost actuators each of which has one rotary motor and one gear reducer. A H∞ controller with friction compensation is designed for the seat suspension control system where the friction is estimated and compensated based on the measurement of seat acceleration. This principal aim of this research was to control the low frequency vibration transferred or amplified by the vehicle (chassis) suspension, and to maintain the passivity of the seat suspension at high frequency (isolation vibration) while taking into consideration the trade-off between the active seat suspension cost and its high frequency performance. Sinusoidal excitations of 1-4.5 Hz were applied to test the active seat suspension both when controlled and when uncontrolled and this is compared with a well-tuned passive heavy duty vehicle seat suspension. The results indicate the effectiveness of the proposed control algorithm within the tested frequencies. Further tests were conducted using the excitations generated from a quarter-car model under bump and random road profiles. The bump road tests indicate the controlled active seat suspension has good transient response performance. The Power Spectral Density (PSD) method and ISO 2631-1 standards were applied to analyse the seat suspension's acceleration under random road conditions. Although some low magnitude and high frequency noise will inevitably be introduced by the active system, the weighted-frequency Root Mean Square (RMS) acceleration shows that this may not have a large effect on ride comfort. In fact, the ride comfort is improved from being an 'a little uncomfortable' to a 'not uncomfortable' level when compared with the well-tuned passive seat suspension. This low cost active seat suspension design and the proposed controller with the easily measured feedback signals are very practical for real

  5. A high speed PC-based data acquisition and control system for positron imaging

    NASA Astrophysics Data System (ADS)

    Leadbeater, T. W.; Parker, D. J.

    2009-06-01

    A modular positron camera with a flexible geometry suitable for performing Positron Emission Particle Tracking (PEPT) studies on a wide range of applications has been constructed. The demand for high speed list mode data storage required for these experiments has motivated the development of an improved data acquisition system to support the existing detectors. A high speed PC-based data acquisition system is presented. This device replaces the old dedicated hardware with a compact, flexible device with the same functionality and superior performance. Data acquisition rates of up to 80 MBytes per second allow coincidence data to be saved to disk for real-time analysis or post processing. The system supports the storage of time information with resolution of a half millisecond and remote trigger data support. Control of the detector system is provided by high-level software running on the same computer.

  6. Flagellar Length Control System: Testing a Simple Model Based on Intraflagellar Transport and Turnover

    PubMed Central

    Marshall, Wallace F.; Qin, Hongmin; Brenni, Mónica Rodrigo; Rosenbaum, Joel L.

    2005-01-01

    Flagellar length regulation provides a simple model system for addressing the general problem of organelle size control. Based on a systems-level analysis of flagellar dynamics, we have proposed a mechanism for flagellar length control in which length is set by the balance of continuous flagellar assembly and disassembly. The model proposes that the assembly rate is length dependent due to the inherent length dependence of intraflagellar transport, whereas disassembly is length independent, such that the two rates can only reach a balance point at a single length. In this report, we test this theoretical model by using three different measurements: 1) the quantity of intraflagellar transport machinery as a function of length, 2) the variation of flagellar length as a function of flagellar number, and 3) the rate of flagellar growth as a function of length. We find that the quantity of intraflagellar transport machinery is independent of length, that flagellar length is a decreasing function of flagellar number, and that flagellar growth rate in regenerating flagella depends on length and not on the time since regeneration began. These results are consistent with the balance-point model for length control. The three strategies used here are not limited to flagella and can in principle be adapted to probe size control systems for any organelle. PMID:15496456

  7. Energy efficient model based algorithm for control of building HVAC systems.

    PubMed

    Kirubakaran, V; Sahu, Chinmay; Radhakrishnan, T K; Sivakumaran, N

    2015-11-01

    Energy efficient designs are receiving increasing attention in various fields of engineering. Heating ventilation and air conditioning (HVAC) control system designs involve improved energy usage with an acceptable relaxation in thermal comfort. In this paper, real time data from a building HVAC system provided by BuildingLAB is considered. A resistor-capacitor (RC) framework for representing thermal dynamics of the building is estimated using particle swarm optimization (PSO) algorithm. With objective costs as thermal comfort (deviation of room temperature from required temperature) and energy measure (Ecm) explicit MPC design for this building model is executed based on its state space representation of the supply water temperature (input)/room temperature (output) dynamics. The controllers are subjected to servo tracking and external disturbance (ambient temperature) is provided from the real time data during closed loop control. The control strategies are ported on a PIC32mx series microcontroller platform. The building model is implemented in MATLAB and hardware in loop (HIL) testing of the strategies is executed over a USB port. Results indicate that compared to traditional proportional integral (PI) controllers, the explicit MPC's improve both energy efficiency and thermal comfort significantly.

  8. Energy efficient model based algorithm for control of building HVAC systems.

    PubMed

    Kirubakaran, V; Sahu, Chinmay; Radhakrishnan, T K; Sivakumaran, N

    2015-11-01

    Energy efficient designs are receiving increasing attention in various fields of engineering. Heating ventilation and air conditioning (HVAC) control system designs involve improved energy usage with an acceptable relaxation in thermal comfort. In this paper, real time data from a building HVAC system provided by BuildingLAB is considered. A resistor-capacitor (RC) framework for representing thermal dynamics of the building is estimated using particle swarm optimization (PSO) algorithm. With objective costs as thermal comfort (deviation of room temperature from required temperature) and energy measure (Ecm) explicit MPC design for this building model is executed based on its state space representation of the supply water temperature (input)/room temperature (output) dynamics. The controllers are subjected to servo tracking and external disturbance (ambient temperature) is provided from the real time data during closed loop control. The control strategies are ported on a PIC32mx series microcontroller platform. The building model is implemented in MATLAB and hardware in loop (HIL) testing of the strategies is executed over a USB port. Results indicate that compared to traditional proportional integral (PI) controllers, the explicit MPC's improve both energy efficiency and thermal comfort significantly. PMID:25869418

  9. Wavelet-based ECG data compression system with linear quality control scheme.

    PubMed

    Ku, Cheng-Tung; Hung, King-Chu; Wu, Tsung-Ching; Wang, Huan-Sheng

    2010-06-01

    Maintaining reconstructed signals at a desired level of quality is crucial for lossy ECG data compression. Wavelet-based approaches using a recursive decomposition process are unsuitable for real-time ECG signal recoding and commonly obtain a nonlinear compression performance with distortion sensitive to quantization error. The sensitive response is caused without compromising the influences of word-length-growth (WLG) effect and unfavorable for the reconstruction quality control of ECG data compression. In this paper, the 1-D reversible round-off nonrecursive discrete periodic wavelet transform is applied to overcome the WLG magnification effect in terms of the mechanisms of error propagation resistance and significant normalization of octave coefficients. The two mechanisms enable the design of a multivariable quantization scheme that can obtain a compression performance with the approximate characteristics of linear distortion. The quantization scheme can be controlled with a single control variable. Based on the linear compression performance, a linear quantization scale prediction model is presented for guaranteeing reconstruction quality. Following the use of the MIT-BIH arrhythmia database, the experimental results show that the proposed system, with lower computational complexity, can obtain much better reconstruction quality control than other wavelet-based methods.

  10. Motion control of nonlinear gantry crane system via priority-based fitness scheme in firefly algorithm

    NASA Astrophysics Data System (ADS)

    Jaafar, Hazriq Izzuan; Latif, Norfaneysa Abd; Kassim, Anuar Mohamed; Abidin, Amar Faiz Zainal; Hussien, Sharifah Yuslinda Syed; Aras, Mohd Shahrieel Mohd

    2015-05-01

    Advanced manufacturing technology made Gantry Crane System (GCS) is one of the suitable heavy machinery transporters and frequently employed in handling with huge materials. The interconnection of trolley movement and payload oscillation has a technical impact which needs to be considered. Once the trolley moves to the desired position with high speed, this will induce undesirable's payload oscillation. This frequent unavoidable load swing causes an efficiency drop, load damages and even accidents. In this paper, a new control strategy of Firefly Algorithm (FA) will be developed to obtain five optimal controller parameters (PID and PD) via Priority-based Fitness Scheme (PFS). Combinations of these five parameters are utilized for controlling trolley movement and minimizing the angle of payload oscillation. This PFS is prioritized based on steady-state error (SSE), overshoot (OS) and settling time (Ts) according to the needs and circumstances. Lagrange equation will be chosen for modeling and simulation will be conducted by using related software. Simulation results show that the proposed control strategy is efficient to control the trolley movement to the desired position and minimize the angle of payload oscillation.

  11. Mobile robot based electrostatic spray system for controlling pests on cotton plants in Iraq

    NASA Astrophysics Data System (ADS)

    Al-Mamury, M.; Manivannan, N.; Al-Raweshidy, H.; Balachandran, W.

    2015-10-01

    A mobile robot based electrostatic spray system was developed to combat pest infestation on cotton plants in Iraq. The system consists of a charged spray nozzle, a CCD camera, a mobile robot (vehicle and arm) and Arduino microcontroller. Arduino microcontroller is used to control the spray nozzle and the robot. Matlab is used to process the image from the CCD camera and to generate the appropriate control signals to the robot and the spray nozzle. COMSOL multi-physics FEM software was used to design the induction electrodes to achieve maximum charge transfer onto the fan spray liquid film resulting in achieving the desired charge/mass ratio of the spray. The charged spray nozzle was operated on short duration pulsed spray mode. Image analysis was employed to investigate the spray deposition on improvised insect targets on an artificial plant.

  12. Controllable nanoscale rotating actuator system based on carbon nanotube and graphene

    NASA Astrophysics Data System (ADS)

    Huang, Jianzhang; Han, Qiang

    2016-04-01

    A controllable nanoscale rotating actuator system consisting of a double carbon nanotube and graphene driven by a temperature gradient is proposed, and its rotating dynamics performance and driving mechanism are investigated through molecular dynamics simulations. The outer tube exhibits stable pure rotation with certain orientation under temperature gradient and the steady rotational speed rises as the temperature gradient increases. It reveals that the driving torque is caused by the difference of atomic van der Waals potentials due to the temperature gradient and geometrical features of carbon nanotube. A theoretical model for driving torque is established based on lattice dynamics theory and its predicted results agree well with molecular dynamics simulations. Further discussion is taken according to the theoretical model. The work in this study would be a guide for design and application of controllable nanoscale rotating devices based on carbon nanotubes and graphene.

  13. A novel liquefied gas based oral controlled release drug delivery system for liquid drug formulations.

    PubMed

    Haznar-Garbacz, Dorota; Garbacz, Grzegorz; Eisenächer, Friederike; Klein, Sandra; Weitschies, Werner

    2012-06-01

    A novel liquefied gas based drug delivery system for the oral delivery of liquid and semi-solid drug formulations is presented. The capsule-shaped system is equipped with a capillary as an element controlling the release rate. The delivery mechanism is based on a constant vapor pressure produced by isopentane as a low-boiling liquefied gas. The liquid drug valproic acid (VA) was used as a model compound. The viscosity was increased by the addition of povidone (PVP). The VA-PVP gel exhibited pseudoplastic rheological properties, the shear rate was above 0.1s(-1), similar to a Newtonian liquid. The gels tested in the gas based delivery system provided near-zero-order release kinetics. The longest delivery time was up to ca. 8h. The system is characterized by high flexibility of the delivery rate, which can be achieved by adjusting system parameters such as the diameter and length of the capillary, the vapor pressure of the propellant and the viscosity of the drug formulation.

  14. The remote supervisory and controlling experiment system of traditional Chinese medicine production based on Fieldbus

    NASA Astrophysics Data System (ADS)

    Zhan, Jinliang; Lu, Pei

    2006-11-01

    Since the quality of traditional Chinese medicine products are affected by raw material, machining and many other factors, it is difficult for traditional Chinese medicine production process especially the extracting process to ensure the steady and homogeneous quality. At the same time, there exist some quality control blind spots due to lacking on-line quality detection means. But if infrared spectrum analysis technology was used in traditional Chinese medicine production process on the basis of off-line analysis to real-time detect the quality of semi-manufactured goods and to be assisted by advanced automatic control technique, the steady and homogeneous quality can be obtained. It can be seen that the on-line detection of extracting process plays an important role in the development of Chinese patent medicines industry. In this paper, the design and implement of a traditional Chinese medicine extracting process monitoring experiment system which is based on PROFIBUS-DP field bus, OPC, and Internet technology is introduced. The system integrates intelligence node which gathering data, superior sub-system which achieving figure configuration and remote supervisory, during the process of traditional Chinese medicine production, monitors the temperature parameter, pressure parameter, quality parameter etc. And it can be controlled by the remote nodes in the VPN (Visual Private Network). Experiment and application do have proved that the system can reach the anticipation effect fully, and with the merits of operational stability, real-time, reliable, convenient and simple manipulation and so on.

  15. Novel flat datacenter network architecture based on scalable and flow-controlled optical switch system.

    PubMed

    Miao, Wang; Luo, Jun; Di Lucente, Stefano; Dorren, Harm; Calabretta, Nicola

    2014-02-10

    We propose and demonstrate an optical flat datacenter network based on scalable optical switch system with optical flow control. Modular structure with distributed control results in port-count independent optical switch reconfiguration time. RF tone in-band labeling technique allowing parallel processing of the label bits ensures the low latency operation regardless of the switch port-count. Hardware flow control is conducted at optical level by re-using the label wavelength without occupying extra bandwidth, space, and network resources which further improves the performance of latency within a simple structure. Dynamic switching including multicasting operation is validated for a 4 x 4 system. Error free operation of 40 Gb/s data packets has been achieved with only 1 dB penalty. The system could handle an input load up to 0.5 providing a packet loss lower that 10(-5) and an average latency less that 500 ns when a buffer size of 16 packets is employed. Investigation on scalability also indicates that the proposed system could potentially scale up to large port count with limited power penalty.

  16. Systems and methods for providing power to a load based upon a control strategy

    DOEpatents

    Perisic, Milun; Kajouke, Lateef A; Ransom, Ray M

    2013-12-24

    Systems and methods are provided for an electrical system. The electrical system includes a load, an interface configured to receive a voltage from a voltage source, and a controller configured to receive the voltage from the voltage source through the interface and to provide a voltage and current to the load. Wherein, when the controller is in a constant voltage mode, the controller provides a constant voltage to the load, when the controller is in a constant current mode, the controller provides a constant current to the load, and when the controller is in a constant power mode, the controller provides a constant power to the load.

  17. Design of the control system for full-color LED display based on MSP430 MCU

    NASA Astrophysics Data System (ADS)

    Li, Xue; Xu, Hui-juan; Qin, Ling-ling; Zheng, Long-jiang

    2013-08-01

    The LED display incorporate the micro electronic technique, computer technology and information processing as a whole, it becomes the most preponderant of a new generation of display media with the advantages of bright in color, high dynamic range, high brightness and long operating life, etc. The LED display has been widely used in the bank, securities trading, highway signs, airport and advertising, etc. According to the display color, the LED display screen is divided into monochrome screen, double color display and full color display. With the diversification of the LED display's color and the ceaseless rise of the display demands, the LED display's drive circuit and control technology also get the corresponding progress and development. The earliest monochrome screen just displaying Chinese characters, simple character or digital, so the requirements of the controller are relatively low. With the widely used of the double color LED display, the performance of its controller will also increase. In recent years, the full color LED display with three primary colors of red, green, blue and grayscale display effect has been highly attention with its rich and colorful display effect. Every true color pixel includes three son pixels of red, green, blue, using the space colour mixture to realize the multicolor. The dynamic scanning control system of LED full-color display is designed based on MSP430 microcontroller technology of the low power consumption. The gray control technology of this system used the new method of pulse width modulation (PWM) and 19 games show principle are combining. This method in meet 256 level grayscale display conditions, improves the efficiency of the LED light device, and enhances the administrative levels feels of the image. Drive circuit used 1/8 scanning constant current drive mode, and make full use of the single chip microcomputer I/O mouth resources to complete the control. The system supports text, pictures display of 256 grayscale

  18. Face Recognition for Access Control Systems Combining Image-Difference Features Based on a Probabilistic Model

    NASA Astrophysics Data System (ADS)

    Miwa, Shotaro; Kage, Hiroshi; Hirai, Takashi; Sumi, Kazuhiko

    We propose a probabilistic face recognition algorithm for Access Control System(ACS)s. Comparing with existing ACSs using low cost IC-cards, face recognition has advantages in usability and security that it doesn't require people to hold cards over scanners and doesn't accept imposters with authorized cards. Therefore face recognition attracts more interests in security markets than IC-cards. But in security markets where low cost ACSs exist, price competition is important, and there is a limitation on the quality of available cameras and image control. Therefore ACSs using face recognition are required to handle much lower quality images, such as defocused and poor gain-controlled images than high security systems, such as immigration control. To tackle with such image quality problems we developed a face recognition algorithm based on a probabilistic model which combines a variety of image-difference features trained by Real AdaBoost with their prior probability distributions. It enables to evaluate and utilize only reliable features among trained ones during each authentication, and achieve high recognition performance rates. The field evaluation using a pseudo Access Control System installed in our office shows that the proposed system achieves a constant high recognition performance rate independent on face image qualities, that is about four times lower EER (Equal Error Rate) under a variety of image conditions than one without any prior probability distributions. On the other hand using image difference features without any prior probabilities are sensitive to image qualities. We also evaluated PCA, and it has worse, but constant performance rates because of its general optimization on overall data. Comparing with PCA, Real AdaBoost without any prior distribution performs twice better under good image conditions, but degrades to a performance as good as PCA under poor image conditions.

  19. A new classification scheme for deep geothermal systems based on geologic controls

    NASA Astrophysics Data System (ADS)

    Moeck, I.

    2012-04-01

    A key element in the characterization, assessment and development of geothermal energy systems is the resource classification. Throughout the past 30 years many classifications and definitions were published mainly based on temperature and thermodynamic properties. In the past classification systems, temperature has been the essential measure of the quality of the resource and geothermal systems have been divided into three different temperature (or enthalpy) classes: low-temperature, moderate-temperature and high-temperature. There are, however, no uniform temperature ranges for these classes. It is still a key requirement of a geothermal classification that resource assessment provides logical and consistent frameworks simplified enough to communicate important aspects of geothermal energy potential to both non-experts and general public. One possible solution may be to avoid classifying geothermal resources by temperature and simply state the range of temperatures at the individual site. Due to technological development, in particular in EGS (Enhanced Geothermal Systems or Engineered Geothermal Systems; both terms are considered synonymously in this thesis) technology, currently there are more geothermal systems potentially economic than 30 years ago. An alternative possibility is to classify geothermal energy systems by their geologic setting. Understanding and characterizing the geologic controls on geothermal systems has been an ongoing focus on different scales from plate tectonics to local tectonics/structural geology. In fact, the geologic setting has a fundamental influence on the potential temperature, on the fluid composition, the reservoir characteristics and whether the system is a predominantly convective or conductive system. The key element in this new classification for geothermal systems is the recognition that a geothermal system is part of a geological system. The structural geological and plate tectonic setting has a fundamental influence on

  20. A Proposal of Ajax Framework for Web-based Supervisory and Control Systems

    NASA Astrophysics Data System (ADS)

    Yanagihara, Shintaro; Ishihara, Akira; Ishii, Toshinao; Kitsuki, Junichi; Seo, Kazuo

    In recent years, with spread of Web application and performance gain of Web browsers, the demand of the web-based supervisory and control(WSCADA) systems based on RIA(Rich Internet Application) is increased. To develop CRUD operations(Create, Read, Update, Delete which corresponds to the basic database operations) of RIA-based web applications, various frameworks and libraries are being provided. However, to develop behavior operations, a lot of program must be written manually. The typical operations of WSCADA are behavior operations, so even if RIA frameworks and libraries are used to develop WSCADA, the productivity of development doesn't improve. Although conceptual models and development environment have been proposed for typical web applications consisted mostly of CRUD operations, those for WSCADA is still the unsolved problem. This paper proposes the user interface model and the development environment for the monitoring user interface program of WSCADA. We focus on the productivity enhancement of the WSCADA development, and propose the Monitoring User Interface Model(MUM) extended Model-View-Controller(MVC) model. We design the Ajax framework and the development environment based on our model. We define the DisplayItem as the advanced View and the MonitoringItem as the advanced Model, and classify the Controller into the Interaction and the Behavior. Our Ajax framework based on web browser's standard technologies, provides the mapping between conceptual model elements. We define the domain specific language for writing the mapping. We design development environment for auto-generating Behavior program from the mapping. In this paper, we evaluate our model and development environment through the experimental development of the typical WSCADA. As a result, the development cost of the WSCADA based on our framework is only one fifth of that based on the typical Ajax library.

  1. FPGA-based Upgrade to RITS-6 Control System, Designed with EMP Considerations

    SciTech Connect

    Harold D. Anderson, John T. Williams

    2009-07-01

    The existing control system for the RITS-6, a 20-MA 3-MV pulsed-power accelerator located at Sandia National Laboratories, was built as a system of analog switches because the operators needed to be close enough to the machine to hear pulsed-power breakdowns, yet the electromagnetic pulse (EMP) emitted would disable any processor-based solutions. The resulting system requires operators to activate and deactivate a series of 110-V relays manually in a complex order. The machine is sensitive to both the order of operation and the time taken between steps. A mistake in either case would cause a misfire and possible machine damage. Based on these constraints, a field-programmable gate array (FPGA) was chosen as the core of a proposed upgrade to the control system. An FPGA is a series of logic elements connected during programming. Based on their connections, the elements can mimic primitive logic elements, a process called synthesis. The circuit is static; all paths exist simultaneously and do not depend on a processor. This should make it less sensitive to EMP. By shielding it and using good electromagnetic interference-reduction practices, it should continue to operate well in the electrically noisy environment. The FPGA has two advantages over the existing system. In manual operation mode, the synthesized logic gates keep the operators in sequence. In addition, a clock signal and synthesized countdown circuit provides an automated sequence, with adjustable delays, for quickly executing the time-critical portions of charging and firing. The FPGA is modeled as a set of states, each state being a unique set of values for the output signals. The state is determined by the input signals, and in the automated segment by the value of the synthesized countdown timer, with the default mode placing the system in a safe configuration. Unlike a processor-based system, any system stimulus that results in an abort situation immediately executes a shutdown, with only a tens

  2. Robust PI-based Frequency Control of Isolated Wind-Diesel Power System with Coordinated Governor, Pitch and Battery Controller

    NASA Astrophysics Data System (ADS)

    Nandar, Cuk Supriyadi Ali; Hashiguchi, Takuhei; Goda, Tadahiro

    A penetration of renewable energy sources such as photovoltaic, wind power etc to prevent global warming is become increasing highly. However, a random unpredictable wind power output may cause frequency fluctuation on isolated hybrid wind-diesel power system. This paper proposes design of coordinated control of governor, pitch and battery to stabilize frequency fluctuation in isolated wind-diesel power system. A well coordinated control between governor, pitch and battery controller are able to improve a performance and also minimize an interaction between the controllers. The structure of the proposed controllers are the first-order PI controller. They are simple and easy to implement in power system utilities. The robustness of the proposed PI controllers are guaranteed by applying an inverse additive perturbation to represent possible unstructured uncertainties in the power system such as variation of system parameters, generating and loading conditions etc. The proposed PI control parameters are optimized and achieved by a genetic algorithm (GA). Simulation studies have been done to show the control effect and robustness of the proposed PI controller in isolated hybrid wind-diesel power system against various disturbances and system uncertainties.

  3. Sensorless Interaction Force Control Based on B-Spline Function for Human-Robot Systems

    NASA Astrophysics Data System (ADS)

    Mitsantisuk, Chowarit; Katsura, Seiichiro; Ohishi, Kiyoshi

    In this paper, to provide precise force sensation of human operator, a twin direct-drive motor system with wire rope mechanism has been developed. The human-robot interaction force and the wire rope tension are independently controlled in acceleration dimension by realizing the dual disturbance observer based on modal space design. In the common mode, it is utilized for control of vibration suppression and wire rope tension. In the differential mode, the purity of human external force with compensation of friction force is obtained. This mode is useful for control of the interaction force of human. Furthermore, the human-robot system that has the ability of support of human interaction force is also proposed. The interaction force generation based on B-spline function is applied to automatically adjust the smooth force command corresponding to the adaptive parameters.
    To analyze the human movement stroke, the multi-sensor scheme is applied to fuse both two motor encoders and acceleration sensor signal by using Kalman filter. From the experimental results, the ability to design different level of assistive force makes it well suited to customized training programs due to time and human movement constraints.

  4. Auto-control of pumping operations in sewerage systems by rule-based fuzzy neural networks

    NASA Astrophysics Data System (ADS)

    Chiang, Y.-M.; Chang, L.-C.; Tsai, M.-J.; Wang, Y.-F.; Chang, F.-J.

    2011-01-01

    Pumping stations play an important role in flood mitigation in metropolitan areas. The existing sewerage systems, however, are facing a great challenge of fast rising peak flow resulting from urbanization and climate change. It is imperative to construct an efficient and accurate operating prediction model for pumping stations to simulate the drainage mechanism for discharging the rainwater in advance. In this study, we propose two rule-based fuzzy neural networks, adaptive neuro-fuzzy inference system (ANFIS) and counterpropagation fuzzy neural network for on-line predicting of the number of open and closed pumps of a pivotal pumping station in Taipei city up to a lead time of 20 min. The performance of ANFIS outperforms that of CFNN in terms of model efficiency, accuracy, and correctness. Furthermore, the results not only show the predictive water levels do contribute to the successfully operating pumping stations but also demonstrate the applicability and reliability of ANFIS in automatically controlling the urban sewerage systems.

  5. Auto-control of pumping operations in sewerage systems by rule-based fuzzy neural networks

    NASA Astrophysics Data System (ADS)

    Chiang, Y.-M.; Chang, L.-C.; Tsai, M.-J.; Wang, Y.-F.; Chang, F.-J.

    2010-09-01

    Pumping stations play an important role in flood mitigation in metropolitan areas. The existing sewerage systems, however, are facing a great challenge of fast rising peak flow resulting from urbanization and climate change. It is imperative to construct an efficient and accurate operating prediction model for pumping stations to simulate the drainage mechanism for discharging the rainwater in advance. In this study, we propose two rule-based fuzzy neural networks, adaptive neuro-fuzzy inference system (ANFIS) and counterpropagatiom fuzzy neural network (CFNN) for on-line predicting of the number of open and closed pumps of a pivotal pumping station in Taipei city up to a lead time of 20 min. The performance of ANFIS outperforms that of CFNN in terms of model efficiency, accuracy, and correctness. Furthermore, the results not only show the predictive water levels do contribute to the successfully operating pumping stations but also demonstrate the applicability and reliability of ANFIS in automatically controlling the urban sewerage systems.

  6. An Intelligent Control System Based on Non-Invasive Man Machine Interaction

    NASA Astrophysics Data System (ADS)

    Drungilas, Darius; Bielskis, Antanas Andrius; Denisov, Vitalij

    This paper presents further development of intelligent multi-agent based e-health care system for people with movement disabilities. The research results present further development of multi-layered model of this system with integration of fuzzy neural control of speed of two wheelchair type robots working in real time by providing movement support for disabled individuals. An approach of filtering of skin conductance (SC) signals using Nadaraya-Watson kernel regression smoothing for emotion recognition of disabled individuals is described and implemented in the system by R software tool. The unsupervised clustering by self organizing maps (SOM) of data sample of physiological parameters extracted from SC signals was proposed in order to reduce teacher noise as well as to increase of speed and accuracy of learning process of multi-layer perceptron (MLP) training.

  7. Observer-based distributed consensus for general nonlinear multi-agent systems with interval control inputs

    NASA Astrophysics Data System (ADS)

    Zhang, Wentao; Liu, Yang

    2016-01-01

    In this paper, observer-based distributed consensus for general nonlinear multi-agent systems with interval control inputs under strongly connected balanced topology is encountered when the relative states of agents are unavailable or undesirable. Theoretical analysis method is further extended to the case of general nonlinear multi-agent systems under switching setting. Moreover, tracking problem on the leader-follower scenario is also explicitly investigated under a mutual assumption that the communication graph, which represents the interaction among agents, contains a directed spanning tree with the leader as its root. It is shown that the consensus for underlying considered multi-agent systems can be desirable as long as the data missing rate does not exceed a certain threshold. Finally, simulation examples are presented to effectively corroborate the analytical findings.

  8. Real-Time, Model-Based Spray-Cooling Control System for Steel Continuous Casting

    NASA Astrophysics Data System (ADS)

    Petrus, Bryan; Zheng, Kai; Zhou, X.; Thomas, Brian G.; Bentsman, Joseph

    2011-02-01

    This article presents a new system to control secondary cooling water sprays in continuous casting of thin steel slabs (CONONLINE). It uses real-time numerical simulation of heat transfer and solidification within the strand as a software sensor in place of unreliable temperature measurements. The one-dimensional finite-difference model, CON1D, is adapted to create the real-time predictor of the slab temperature and solidification state. During operation, the model is updated with data collected by the caster automation systems. A decentralized controller configuration based on a bank of proportional-integral controllers with antiwindup is developed to maintain the shell surface-temperature profile at a desired set point. A new method of set-point generation is proposed to account for measured mold heat flux variations. A user-friendly monitor visualizes the results and accepts set-point changes from the caster operator. Example simulations demonstrate how a significantly better shell surface-temperature control is achieved.

  9. A scalable bus-based attitude control system for Solar Sails

    NASA Astrophysics Data System (ADS)

    Adeli, S. Nasir; Lappas, Vaios J.; Wie, Bong

    2011-12-01

    Recently, there has been a renewed interest in Solar Sails as an alternative means of space propulsion. Many different attitude control systems have been designed for Solar Sails taking advantage of the centre-of-mass (CM)/centre-of-pressure (CP) offset while utilising the main sail structure to position the actuators. However, by attaching actuators to the main sail, these systems increase the risks involved in the deployment subsystem. In this paper we propose an attitude control system (ACS) decoupled from the main sail booms and attached to the spacecraft bus. We use ballast masses to change the CM and highly reflective panels to change the CP, achieving 3-axis control. As a result of the decoupled nature of the ACS, scalability and simplicity can be achieved. This is shown through sizing and simulation of the ACS for three different sail sizes, the 5 m Cubesail, 40 m GeoSail and 245 m interstellar heliopause probe (IHP). The scalable bus-based ACS decreases the risks and complexity involved in the design of the sail deployment subsystem and can be employed alongside any available sail deployment mechanisms.

  10. A framework for the Subaru Telescope observation control system based on the command design pattern

    NASA Astrophysics Data System (ADS)

    Jeschke, Eric; Bon, Bruce; Inagaki, Takeshi; Streeper, Sam

    2008-08-01

    Subaru Telescope is developing a second-generation Observation Control System that specifically addresses some of the deficiencies of the current Subaru OCS. One area of concern is better extensibility: the current system uses a custom language for implementing commands with a complex macro processing subsystem written in C. It is laborious to improve the language and awkward for scientists to extend and use standard programming techniques. Our Generation 2 OCS provides a lightweight, object-oriented task framework based on the Command design pattern. The framework provides a base task class that abstracts services for processing status and other common infrastructure activities. Upon this are built and provided a set of "atomic" tasks for telescope and instrument commands. A set of "container" tasks based on common sequential and concurrent command processing paradigms is also included. Since all tasks share the same exact interface, it is straightforward to build up compound tasks by plugging simple tasks into container tasks and container tasks into other containers, and so forth. In this way various advanced astronomical workflows can be readily created, with well controlled behaviors. In addition, since tasks are written in Python, it is easy for astronomers to subclass and extend the standard observatory tasks with their own custom extensions and behaviors, in a high-level, full-featured programming language. In this talk we will provide an overview of the task framework design and present preliminary results on the use of the framework during two separate engineering runs.

  11. Fuzzy logic based intelligent control of a variable speed cage machine wind generation system

    SciTech Connect

    Simoes, M.G.; Bose, B.K.; Spiegel, R.J.

    1997-01-01

    The paper describes a variable speed wind generation system where fuzzy logic principles are used for efficiency optimization and performance enhancement control. A squirrel cage induction generator feeds the power to a double-sided pulse width modulated converter system which pumps power to a utility grid or can supply to an autonomous system. The generation system has fuzzy logic control with vector control in the inner loops. A fuzzy controller tracks the generator speed with the wind velocity to extract the maximum power. A second fuzzy controller programs the machine flux for light load efficiency improvement, and a third fuzzy controller gives robust speed control against wind gust and turbine oscillatory torque. The complete control system has been developed, analyzed, and validated by simulation study. Performances have then been evaluated in detail.

  12. Ground Control Point - Wireless System Network for UAV-based environmental monitoring applications

    NASA Astrophysics Data System (ADS)

    Mejia-Aguilar, Abraham

    2016-04-01

    In recent years, Unmanned Aerial Vehicles (UAV) have seen widespread civil applications including usage for survey and monitoring services in areas such as agriculture, construction and civil engineering, private surveillance and reconnaissance services and cultural heritage management. Most aerial monitoring services require the integration of information acquired during the flight (such as imagery) with ground-based information (such as GPS information or others) for improved ground truth validation. For example, to obtain an accurate 3D and Digital Elevation Model based on aerial imagery, it is necessary to include ground-based information of coordinate points, which are normally acquired with surveying methods based on Global Position Systems (GPS). However, GPS surveys are very time consuming and especially for longer time series of monitoring data repeated GPS surveys are necessary. In order to improve speed of data collection and integration, this work presents an autonomous system based on Waspmote technologies build on single nodes interlinked in a Wireless Sensor Network (WSN) star-topology for ground based information collection and later integration with surveying data obtained by UAV. Nodes are designed to be visible from the air, to resist extreme weather conditions with low-power consumption. Besides, nodes are equipped with GPS as well as Inertial Measurement Unit (IMU), accelerometer, temperature and soil moisture sensors and thus provide significant advantages in a broad range of applications for environmental monitoring. For our purpose, the WSN transmits the environmental data with 3G/GPRS to a database on a regular time basis. This project provides a detailed case study and implementation of a Ground Control Point System Network for UAV-based vegetation monitoring of dry mountain grassland in the Matsch valley, Italy.

  13. Fountain code-based error control scheme for dimmable visible light communication systems

    NASA Astrophysics Data System (ADS)

    Feng, Lifang; Hu, Rose Qingyang; Wang, Jianping; Xu, Peng

    2015-07-01

    In this paper, a novel error control scheme using Fountain codes is proposed in on-off keying (OOK) based visible light communications (VLC) systems. By using Fountain codes, feedback information is needed to be sent back to the transmitter only when transmitted messages are successfully recovered. Therefore improved transmission efficiency, reduced protocol complexity and relative little wireless link-layer delay are gained. By employing scrambling techniques and complementing symbols, the least complemented symbols are needed to support arbitrary dimming target values, and the value of entropy of encoded message are increased.

  14. Fuzzy logic based feedback control system for laser beam pointing stabilization.

    PubMed

    Singh, Ranjeet; Patel, Kiran; Govindarajan, J; Kumar, Ajai

    2010-09-20

    This paper reports a fuzzy logic based feedback control system for beam pointing stabilization of a high-power nanosecond Nd:YAG laser operating at 30 Hz. This is achieved by generating the correcting signal for each consequent pulse from the error in the pointing position of the previous laser pulse. We have successfully achieved a reduction of beam position fluctuation from ±60 to ±5.0 μrad without the focusing optics and ±0.9 μrad with focusing optics. PMID:20856289

  15. Development and in vivo evaluation of an implantable left ventricular assist system with an impedance based monitoring and control system.

    PubMed

    Nakatani, T; Anai, H; Eya, K; Wakisaka, Y; Toda, K; Taenaka, Y; Tatsumi, E; Masuzawa, T; Baba, Y; Takano, H

    1995-01-01

    We have developed an implantable pneumatically driven diaphragm left ventricular assist system (LVAS) for small adults, and an electric impedance based monitoring and control system (Z system). In this Z system, measurement of electric impedance of the blood chamber is performed by charging an alternating current with a constant amplitude between two metal connectors without compromising anti-thrombogenicity. Automatic calibration was performed periodically by measuring trough values of impedance in the blood chamber for several beats while the blood pump was in a full-fill state under preset driving conditions. For precise control of the fill-to-empty (F/E) drive, an automatic trigger level adjustment method was developed. This method is an automatic searching algorithm that identifies the volume change of the last ejection or filling by the Z system and settles the next trigger level to maintain a definite stroke volume. In chronic in vivo evaluation, this LVAS was used in 13 adult goats. The pump was installed between the LV apex and the descending aorta and was placed in the abdominal wall. Pump output ranged from 2.5 to 5.8 L/min, and the Z system provided good monitoring. The F/E drive was achieved satisfactorily by this Z system. The physical condition of the goats was excellent for as long as 19 weeks. Hematologic, hepatic, and renal functions were within the normal range, and no prominent thromboembolic symptoms were observed. A new mobile control drive unit with this Z system is being developed. We conclude that this LVAS with the Z system is promising for long-term use in a clinical setting.

  16. LMI-based stability analysis of fuzzy-model-based control systems using approximated polynomial membership functions.

    PubMed

    Narimani, Mohammand; Lam, H K; Dilmaghani, R; Wolfe, Charles

    2011-06-01

    Relaxed linear-matrix-inequality-based stability conditions for fuzzy-model-based control systems with imperfect premise matching are proposed. First, the derivative of the Lyapunov function, containing the product terms of the fuzzy model and fuzzy controller membership functions, is derived. Then, in the partitioned operating domain of the membership functions, the relations between the state variables and the mentioned product terms are represented by approximated polynomials in each subregion. Next, the stability conditions containing the information of all subsystems and the approximated polynomials are derived. In addition, the concept of the S-procedure is utilized to release the conservativeness caused by considering the whole operating region for approximated polynomials. It is shown that the well-known stability conditions can be special cases of the proposed stability conditions. Simulation examples are given to illustrate the validity of the proposed approach.

  17. Integrated quality control: implementation and validation of instrument function checks and procedural controls for a cartridge-based point-of-care system for critical care analysis.

    PubMed

    D'Orazio, Paul; Mansouri, Sohrab

    2013-03-01

    In this article, the process used to develop and validate an integrated quality-control system for a cartridge-based, point-of-care system for critical care analysis is outlined. Application of risk management principles has resulted in a quality control system using a combination of statistical quality control with onboard reference solutions and failure pattern recognition used to flag common failure modes during the analytical phase of the testing process. A combination of traditional external quality control, integrated quality control to monitor ongoing instrument functionality, operator training, and other laboratory-implemented monitors is most effective in controlling known failure modes during the testing process.

  18. Pythium invasion of plant-based life support systems: biological control and sources

    NASA Technical Reports Server (NTRS)

    Jenkins, D. G.; Cook, K. L.; Garland, J. L.; Board, K. F.; Sager, J. C. (Principal Investigator)

    2000-01-01

    Invasion of plant-based life support systems by plant pathogens could cause plant disease and disruption of life support capability. Root rot caused by the fungus, Pythium, was observed during tests of prototype plant growth systems containing wheat at the Kennedy Space Center (KSC). We conducted experiments to determine if the presence of complex microbial communities in the plant root zone (rhizosphere) resisted invasion by the Pythium species isolated from the wheat root. Rhizosphere inocula of different complexity (as assayed by community-level physiological profile: CLPP) were developed using a dilution/extinction approach, followed by growth in hydroponic rhizosphere. Pythium growth on wheat roots and concomitant decreases in plant growth were inversely related to the complexity of the inocula during 20-day experiments in static hydroponic systems. Pythium was found on the seeds of several different wheat cultivars used in controlled environmental studies, but it is unclear if the seed-borne fungal strain(s) were identical to the pathogenic strain recovered from the KSC studies. Attempts to control pathogens and their effects in hydroponic life support systems should include early inoculation with complex microbial communities, which is consistent with ecological theory.

  19. A ground based phase control system for the solar power satellite. Executive summary, volume 1, phase 3

    NASA Technical Reports Server (NTRS)

    Chie, C. M.

    1980-01-01

    The Solar Power Satellite (SPS) concept and the reference phase control system investigated in earlier efforts are reviewed. A summary overview of the analysis and selection of the pilot signal and power transponder design is presented along with the SOLARSIM program development and the simulated SPS phase control performance. Evaluations of the ground based phase control system as an alternate phase control concept are summarized.

  20. Quasi-optimum design of a six degree of freedom moving base simulator control system

    NASA Technical Reports Server (NTRS)

    Friedland, B.; Ling, C.; Hutton, M. F.

    1973-01-01

    The design of a washout control system for a moving base simulator is treated by a quasi-optimum control technique. The broad objective of the design is to reproduce the sensed motion of a six degree of freedom simulator as accurately as possible without causing the simulator excursions to exceed specified limits. A performance criterion is established that weights magnitude and direction errors in specific force and in angular velocity and attempts to maintain the excursion within set limits by penalizing excessive excursions. A FORTRAN routine for relizing the washout law was developed and typical time histories using the washout routine were simulated for a range of parameters in the penalty- and weighting-functions. These time histories and the listing of the routine are included in the report.

  1. A Web-Based System for Monitoring and Controlling Multidisciplinary Design Projects

    NASA Technical Reports Server (NTRS)

    Salas, Andrea O.; Rogers, James L.

    1997-01-01

    In today's competitive environment, both industry and government agencies are under enormous pressure to reduce the time and cost of multidisciplinary design projects. A number of frameworks have been introduced to assist in this process by facilitating the integration of and communication among diverse disciplinary codes. An examination of current frameworks reveals weaknesses in various areas such as sequencing, displaying, monitoring, and controlling the design process. The objective of this research is to explore how Web technology, in conjunction with an existing framework, can improve these areas of weakness. This paper describes a system that executes a sequence of programs, monitors and controls the design process through a Web-based interface, and visualizes intermediate and final results through the use of Java(Tm) applets. A small sample problem, which includes nine processes with two analysis programs that are coupled to an optimizer, is used to demonstrate the feasibility of this approach.

  2. A distributed, graphical user interface based, computer control system for atomic physics experiments

    NASA Astrophysics Data System (ADS)

    Keshet, Aviv; Ketterle, Wolfgang

    2013-01-01

    Atomic physics experiments often require a complex sequence of precisely timed computer controlled events. This paper describes a distributed graphical user interface-based control system designed with such experiments in mind, which makes use of off-the-shelf output hardware from National Instruments. The software makes use of a client-server separation between a user interface for sequence design and a set of output hardware servers. Output hardware servers are designed to use standard National Instruments output cards, but the client-server nature should allow this to be extended to other output hardware. Output sequences running on multiple servers and output cards can be synchronized using a shared clock. By using a field programmable gate array-generated variable frequency clock, redundant buffers can be dramatically shortened, and a time resolution of 100 ns achieved over effectively arbitrary sequence lengths.

  3. Deadlock-free genetic scheduling algorithm for automated manufacturing systems based on deadlock control policy.

    PubMed

    Xing, KeYi; Han, LiBin; Zhou, MengChu; Wang, Feng

    2012-06-01

    Deadlock-free control and scheduling are vital for optimizing the performance of automated manufacturing systems (AMSs) with shared resources and route flexibility. Based on the Petri net models of AMSs, this paper embeds the optimal deadlock avoidance policy into the genetic algorithm and develops a novel deadlock-free genetic scheduling algorithm for AMSs. A possible solution of the scheduling problem is coded as a chromosome representation that is a permutation with repetition of parts. By using the one-step look-ahead method in the optimal deadlock control policy, the feasibility of a chromosome is checked, and infeasible chromosomes are amended into feasible ones, which can be easily decoded into a feasible deadlock-free schedule. The chromosome representation and polynomial complexity of checking and amending procedures together support the cooperative aspect of genetic search for scheduling problems strongly.

  4. The evolution of CELSS for lunar bases. [Controlled Ecological Life Support Systems

    NASA Technical Reports Server (NTRS)

    Macelroy, R. D.; Klein, H. P.; Averner, M. M.

    1985-01-01

    A bioregenerative life support system designed to address the fundamental requirements of a functioning independent lunar base is presented in full. Issues to be discussed are associated with CELSS weight, volume and cost of operation. The fundamental CELSS component is a small, highly automated module containing plants which photosynthesize and provide the crew with food, water and oxygen. Hydrogen, nitrogen and carbon dioxide will be initially brought in from earth, recycled and their waste products conserved. As the insufficiency of buffers necessitates stringent cybernetic control, a stable state will be maintained by computer control. Through genetic engineering and carbon dioxide, temperature, and nutrient manipulation, plant productivity can be increased, while the area necessary for growth and illumination energy decreased. In addition, photosynthetic efficiency can be enhanced through lamp design, fiber optics and the use of appropriate wavelengths. Crop maintenance will be performed by robotics, as a means of preventing plant ailments.

  5. An adaptive critic-based scheme for consensus control of nonlinear multi-agent systems

    NASA Astrophysics Data System (ADS)

    Heydari, Ali; Balakrishnan, S. N.

    2014-12-01

    The problem of decentralised consensus control of a network of heterogeneous nonlinear systems is formulated as an optimal tracking problem and a solution is proposed using an approximate dynamic programming based neurocontroller. The neurocontroller training comprises an initial offline training phase and an online re-optimisation phase to account for the fact that the reference signal subject to tracking is not fully known and available ahead of time, i.e., during the offline training phase. As long as the dynamics of the agents are controllable, and the communication graph has a directed spanning tree, this scheme guarantees the synchronisation/consensus even under switching communication topology and directed communication graph. Finally, an aerospace application is selected for the evaluation of the performance of the method. Simulation results demonstrate the potential of the scheme.

  6. Adaptive Control System of Hydraulic Pressure Based on The Mathematical Modeling

    NASA Astrophysics Data System (ADS)

    Pilipenko, A. V.; Pilipenko, A. P.; Kanatnikov, N. V.

    2016-04-01

    In this paper, the authors highlight the problem of replacing an old heavy industrial equipment, and offer the replacement of obsolete control systems on the modern adaptive control system, which takes into account changes in the hydraulic system of the press and compensates them with a corrective action. The proposed system can reduce a water hammer and thereby increase the durability of the hydraulic system and tools.

  7. A cooperatively-controlled image guided robot system for skull base surgery.

    PubMed

    Kazanzides, Peter; Xia, Tian; Baird, Clint; Jallo, George; Hayes, Kathryn; Nakajima, Nobuyuki; Hata, Nobuhiko

    2008-01-01

    We created an image-guided robot system to assist with skull base drilling by integrating a robot, a commercial navigation system, and an open source visualization platform. The objective of this procedure is to create a cavity in the skull base to allow access for neurosurgical interventions. The motivation for introducing an image-guided robot is to improve safety by preventing the surgeon from accidentally damaging critical structures during the drilling procedure. Our approach is to attach the cutting tool to the robot end-effector and operate the robot in a cooperative control mode, where robot motion is determined from the forces and torques applied by the surgeon. We employ "virtual fixtures" to constrain the motion of the cutting tool so that it remains in the safe zone that was defined on a preoperative CT scan. This paper presents the system design and the results of phantom and cadaveric experiments. Both experiments have demonstrated the feasibility of the system, with average overcut error at about 1 mm and maximum errors at 2.5 mm.

  8. Load Control System Reliability

    SciTech Connect

    Trudnowski, Daniel

    2015-04-03

    This report summarizes the results of the Load Control System Reliability project (DOE Award DE-FC26-06NT42750). The original grant was awarded to Montana Tech April 2006. Follow-on DOE awards and expansions to the project scope occurred August 2007, January 2009, April 2011, and April 2013. In addition to the DOE monies, the project also consisted of matching funds from the states of Montana and Wyoming. Project participants included Montana Tech; the University of Wyoming; Montana State University; NorthWestern Energy, Inc., and MSE. Research focused on two areas: real-time power-system load control methodologies; and, power-system measurement-based stability-assessment operation and control tools. The majority of effort was focused on area 2. Results from the research includes: development of fundamental power-system dynamic concepts, control schemes, and signal-processing algorithms; many papers (including two prize papers) in leading journals and conferences and leadership of IEEE activities; one patent; participation in major actual-system testing in the western North American power system; prototype power-system operation and control software installed and tested at three major North American control centers; and, the incubation of a new commercial-grade operation and control software tool. Work under this grant certainly supported the DOE-OE goals in the area of “Real Time Grid Reliability Management.”

  9. The equipment access software for a distributed UNIX-based accelerator control system

    NASA Astrophysics Data System (ADS)

    Trofimov, Nikolai; Zelepoukine, Serguei; Zharkov, Eugeny; Charrue, Pierre; Gareyte, Claire; Poirier, Hervé

    1994-12-01

    This paper presents a generic equipment access software package for a distributed control system using computers with UNIX or UNIX-like operating systems. The package consists of three main components, an application Equipment Access Library, Message Handler and Equipment Data Base. An application task, which may run in any computer in the network, sends requests to access equipment through Equipment Library calls. The basic request is in the form Equipment-Action-Data and is routed via a remote procedure call to the computer to which the given equipment is connected. In this computer the request is received by the Message Handler. According to the type of the equipment connection, the Message Handler either passes the request to the specific process software in the same computer or forwards it to a lower level network of equipment controllers using MIL1553B, GPIB, RS232 or BITBUS communication. The answer is then returned to the calling application. Descriptive information required for request routing and processing is stored in the real-time Equipment Data Base. The package has been written to be portable and is currently available on DEC Ultrix, LynxOS, HPUX, XENIX, OS-9 and Apollo domain.

  10. A vision-based tool for the control of hydraulic structures in sewer systems

    NASA Astrophysics Data System (ADS)

    Nguyen, L.; Sage, D.; Kayal, S.; Jeanbourquin, D.; Rossi, L.

    2009-04-01

    monitoring software has the following requirements: visual analysis of particular hydraulic behavior, automatic vision-based flow measurements, automatic alarm system for particular events (overflows, risk of flooding, etc), database for data management (images, events, measurements, etc.), ability to be controlled remotely. The software is implemented in modular server/client architecture under LabVIEW development system. We have conducted conclusive in situ tests in various sewers configurations (CSOs, storm-water sewerage, WWTP); they have shown the ability of the HydroPix to perform accurate monitoring of hydraulic structures. Visual information demonstrated a better understanding of the flow behavior in complex and difficult environment.

  11. Detection and control of combustion instability based on the concept of dynamical system theory

    NASA Astrophysics Data System (ADS)

    Gotoda, Hiroshi; Shinoda, Yuta; Kobayashi, Masaki; Okuno, Yuta; Tachibana, Shigeru

    2014-02-01

    We propose an online method of detecting combustion instability based on the concept of dynamical system theory, including the characterization of the dynamic behavior of combustion instability. As an important case study relevant to combustion instability encountered in fundamental and practical combustion systems, we deal with the combustion dynamics close to lean blowout (LBO) in a premixed gas-turbine model combustor. The relatively regular pressure fluctuations generated by thermoacoustic oscillations transit to low-dimensional intermittent chaos owing to the intermittent appearance of burst with decreasing equivalence ratio. The translation error, which is characterized by quantifying the degree of parallelism of trajectories in the phase space, can be used as a control variable to prevent LBO.

  12. Detection and control of combustion instability based on the concept of dynamical system theory.

    PubMed

    Gotoda, Hiroshi; Shinoda, Yuta; Kobayashi, Masaki; Okuno, Yuta; Tachibana, Shigeru

    2014-02-01

    We propose an online method of detecting combustion instability based on the concept of dynamical system theory, including the characterization of the dynamic behavior of combustion instability. As an important case study relevant to combustion instability encountered in fundamental and practical combustion systems, we deal with the combustion dynamics close to lean blowout (LBO) in a premixed gas-turbine model combustor. The relatively regular pressure fluctuations generated by thermoacoustic oscillations transit to low-dimensional intermittent chaos owing to the intermittent appearance of burst with decreasing equivalence ratio. The translation error, which is characterized by quantifying the degree of parallelism of trajectories in the phase space, can be used as a control variable to prevent LBO. PMID:25353548

  13. Space construction base support requirements for environmental control and life support systems

    NASA Technical Reports Server (NTRS)

    Thiele, R. J.; Secord, T. C.; Murphy, G. L.

    1977-01-01

    A Space Station analysis study is being performed for NASA which identifies cost-effective Space Station options that can provide a space facility capable of performing space construction, space manufacturing, cosmological research, earth services, and other functions. A space construction base concept for the construction of large structures, such as those needed to implement satellite solar power for earth usage, will be used as a basis for discussing requirements that impact the design selection, level of integration, and operation of environmental control and life support systems (ECLSS). The space construction base configuration also provides a basic Space Station facility that can accommodate biological manufacturing modules, ultrapure glasses manufacturing modules, and modules for other services in a building-block fashion. Examples of special problems that could dictate hardware required to augment the basic ECLSS for autonomous modules will be highlighted. Additionally, overall intravehicular (IVA) and extravehicular (EVA) activities and requirements that could impact the basic station ECLSS degree of closure are discussed.

  14. Takagi-Sugeno fuzzy-model-based fault detection for networked control systems with Markov delays.

    PubMed

    Zheng, Ying; Fang, Huajing; Wang, Hua O

    2006-08-01

    A Takagi-Sugeno (T-S) model is employed to represent a networked control system (NCS) with different network-induced delays. Comparing with existing NCS modeling methods, this approach does not require the knowledge of exact values of network-induced delays. Instead, it addresses situations involving all possible network-induced delays. Moreover, this approach also handles data-packet loss. As an application of the T-S-based modeling method, a parity-equation approach and a fuzzy-observer-based approach for fault detection of an NCS were developed. An example of a two-link inverted pendulum is used to illustrate the utility and viability of the proposed approaches.

  15. Vision based interface system for hands free control of an intelligent wheelchair

    PubMed Central

    Ju, Jin Sun; Shin, Yunhee; Kim, Eun Yi

    2009-01-01

    Background Due to the shift of the age structure in today's populations, the necessities for developing the devices or technologies to support them have been increasing. Traditionally, the wheelchair, including powered and manual ones, is the most popular and important rehabilitation/assistive device for the disabled and the elderly. However, it is still highly restricted especially for severely disabled. As a solution to this, the Intelligent Wheelchairs (IWs) have received considerable attention as mobility aids. The purpose of this work is to develop the IW interface for providing more convenient and efficient interface to the people the disability in their limbs. Methods This paper proposes an intelligent wheelchair (IW) control system for the people with various disabilities. To facilitate a wide variety of user abilities, the proposed system involves the use of face-inclination and mouth-shape information, where the direction of an IW is determined by the inclination of the user's face, while proceeding and stopping are determined by the shapes of the user's mouth. Our system is composed of electric powered wheelchair, data acquisition board, ultrasonic/infra-red sensors, a PC camera, and vision system. Then the vision system to analyze user's gestures is performed by three stages: detector, recognizer, and converter. In the detector, the facial region of the intended user is first obtained using Adaboost, thereafter the mouth region is detected based on edge information. The extracted features are sent to the recognizer, which recognizes the face inclination and mouth shape using statistical analysis and K-means clustering, respectively. These recognition results are then delivered to the converter to control the wheelchair. Result & conclusion The advantages of the proposed system include 1) accurate recognition of user's intention with minimal user motion and 2) robustness to a cluttered background and the time-varying illumination. To prove these

  16. Energy-Saving Tunnel Illumination System Based on LED's Intelligent Control

    NASA Astrophysics Data System (ADS)

    Guo, Shanshan; Gu, Hanting; Wu, Lan; Jiang, Shuixiu

    2011-02-01

    At present there is a lot of electric energy wastage in tunnel illumination, whose design is based on the maximum brightness outside and the maximum vehicle speed all year round. LED's energy consumption is low, and the control of its brightness is simple and effective. It can be quickly adjusted between 0-100% of its maximum brightness, and will not affect the service life. Therefore, using LED as tunnel's illumination source, we can achieve a good energy saving effect. According to real-time data acquisition of vehicle speed, traffic flow and brightness outside the tunnel, the auto real-time control of tunnel illumination can be achieved. And the system regulated the LED luminance by means of combination of LED power module and intelligent control module. The tunnel information was detected by inspection equipments, which included luminometer, vehicle detector, and received by RTU(Remote Terminal Unit), then synchronously transmitted to PC. After data processing, RTU emitted the dimming signal to the LED driver to adjust the brightness of LED. Despite the relatively high cost of high-power LED lights, the enormous energy-saving effect and the well-behaved controllability is beyond compare to other lighting devices.

  17. A lower limb exoskeleton control system based on steady state visual evoked potentials

    NASA Astrophysics Data System (ADS)

    Kwak, No-Sang; Müller, Klaus-Robert; Lee, Seong-Whan

    2015-10-01

    Objective. We have developed an asynchronous brain-machine interface (BMI)-based lower limb exoskeleton control system based on steady-state visual evoked potentials (SSVEPs). Approach. By decoding electroencephalography signals in real-time, users are able to walk forward, turn right, turn left, sit, and stand while wearing the exoskeleton. SSVEP stimulation is implemented with a visual stimulation unit, consisting of five light emitting diodes fixed to the exoskeleton. A canonical correlation analysis (CCA) method for the extraction of frequency information associated with the SSVEP was used in combination with k-nearest neighbors. Main results. Overall, 11 healthy subjects participated in the experiment to evaluate performance. To achieve the best classification, CCA was first calibrated in an offline experiment. In the subsequent online experiment, our results exhibit accuracies of 91.3 ± 5.73%, a response time of 3.28 ± 1.82 s, an information transfer rate of 32.9 ± 9.13 bits/min, and a completion time of 1100 ± 154.92 s for the experimental parcour studied. Significance. The ability to achieve such high quality BMI control indicates that an SSVEP-based lower limb exoskeleton for gait assistance is becoming feasible.

  18. A comparison of two software architectural styles for space-based control systems

    NASA Technical Reports Server (NTRS)

    Dvorak, D.

    2003-01-01

    In the hardware/software design of control systems it is almost an article of faith to decompose a system into loosely coupled subsystems, with state variables encapsulated inside device and subsystem objects.

  19. A program to evaluate a control system based on feedback of aerodynamic pressure differentials, part 1

    NASA Technical Reports Server (NTRS)

    Hrabak, R. R.; Levy, D. W.; Finn, P.; Roskam, J.

    1981-01-01

    The use of pressure differentials in a flight control system was evaluated. The pressure profile around the test surface was determined using two techniques: (1) windtunnel data (actual); and (2) NASA/Langley Single Element Airfoil Computer Program (theoretical). The system designed to evaluate the concept of using pressure differentials is composed of a sensor drive and power amplifiers, actuator, position potentiometer, and a control surface. The characteristics (both desired and actual) of the system and each individual component were analyzed. The desired characteristics of the system as a whole are given. The flight control system developed, the testing procedures and data reduction methods used, and theoretical frequency response analysis are described.

  20. A knowledge-based system design/information tool for aircraft flight control systems

    NASA Technical Reports Server (NTRS)

    Mackall, Dale A.; Allen, James G.

    1989-01-01

    Flight test experiences of the X-29 forward-swept wing, the advanced fighter technology integration (AFTI) F-16, and the highly maneuverable aircraft technology (HiMAT) programs are reviewed. Significant operating anomalies in these programs and the design errors which caused them are examined. The functions which a system design/information tool should provide to assist designers in avoiding errors are identified.

  1. Observer-based output feedback control of discrete-time linear systems with input and output delays

    NASA Astrophysics Data System (ADS)

    Zhou, Bin

    2014-11-01

    In this paper, we study observer-based output feedback control of discrete-time linear systems with both multiple input and output delays. By generalising our recently developed truncated predictor feedback approach for state feedback stabilisation of discrete-time time-delay systems to the design of observer-based output feedback, two types of observer-based output feedback controllers, one being memory and the other memoryless, are constructed. Both full-order and reduced-order observer-based controllers are established in both the memory and memoryless schemes. It is shown that the separation principle holds for the memory observer-based output feedback controllers, but does not hold for the memoryless ones. We further show that the proposed observer-based output feedback controllers solve both the l2 and l∞ semi-global stabilisation problems. A numerical example is given to illustrate the effectiveness of the proposed approaches.

  2. Development and Application of a ZigBee-Based Building Energy Monitoring and Control System

    PubMed Central

    Peng, Changhai

    2014-01-01

    Increasing in energy consumption, particularly with the ever-increasing growth and development of urban systems, has become a major concern in most countries. In this paper, the authors propose a cost-effective ZigBee-based building energy monitoring and control system (ZBEMCS), which is composed of a gateway, a base station, and sensors. Specifically, a new hardware platform for power sensor nodes is developed to perform both local/remote power parameter measurement and power on/off switching for electric appliances. The experimental results show that the ZBEMCS can easily monitor energy usage with a high level of accuracy. Two typical applications of ZBEMCS such as subentry metering and household metering of building energy are presented. The former includes lighting socket electricity, HVAC electricity, power electricity and special electricity. The latter includes household metering according to the campus's main function zone and each college or department. Therefore, this system can be used for energy consumption monitoring, long-term energy conservation planning, and the development of automated energy conservation for building applications. PMID:25254249

  3. Development and application of a ZigBee-based building energy monitoring and control system.

    PubMed

    Peng, Changhai; Qian, Kun

    2014-01-01

    Increasing in energy consumption, particularly with the ever-increasing growth and development of urban systems, has become a major concern in most countries. In this paper, the authors propose a cost-effective ZigBee-based building energy monitoring and control system (ZBEMCS), which is composed of a gateway, a base station, and sensors. Specifically, a new hardware platform for power sensor nodes is developed to perform both local/remote power parameter measurement and power on/off switching for electric appliances. The experimental results show that the ZBEMCS can easily monitor energy usage with a high level of accuracy. Two typical applications of ZBEMCS such as subentry metering and household metering of building energy are presented. The former includes lighting socket electricity, HVAC electricity, power electricity and special electricity. The latter includes household metering according to the campus's main function zone and each college or department. Therefore, this system can be used for energy consumption monitoring, long-term energy conservation planning, and the development of automated energy conservation for building applications. PMID:25254249

  4. Development of a Windows-based Modeling System for Simulating Microtopography-Controlled Overland Flow

    NASA Astrophysics Data System (ADS)

    Chu, X.; Yang, J.; chi, Y.; Yang, Y.; Zhang, J.

    2011-12-01

    Surface microtopography affects both temporal variability and spatial distributions of a series of rainfall-infiltration-runoff hydrologic processes. A comprehensive Windows-based modeling system is developed in this study for simulating microtopography-controlled puddle-to-puddle (P2P) overland flow. As a fundamental step, a puddle delineation tool is used for characterizing surface microtopography, delineating puddles and their relationships, determining flow directions and accumulations, and precisely computing maximum depression storage (MDS) and maximum ponding area (MPA). The P2P modeling system simulates the dynamic P2P filling, spilling, and merging overland flow processes on either impervious or infiltrating surfaces. The Windows interface allows users to prepare their input data, run the models (both puddle delineation and P2P modeling), and visualize simulation results in formats of tables, graphs (2D and 3D), and animations. The wizard particularly facilitates computer-guided, step-by-step P2P overland flow modeling. In addition, a set of stand-alone tools are incorporated in the P2P modeling system, including 2D and 3D visualization and animation tools, laser scanner data combination tool, image-based depression storage computation tool, image correction tool, coordinate transformation tool, slope removal tool, and fractal analysis tool. Testing examples demonstrate simulations of P2P overland flow on various microtopographic surfaces and usefulness of the visualization and hydrotopographic analysis tools.

  5. CNEOST Control Software System

    NASA Astrophysics Data System (ADS)

    Wang, X.; Zhao, H. B.; Xia, Y.; Lu, H.; Li, B.

    2015-03-01

    In 2013, CNEOST (China Near Earth Object Survey Telescope) adapted its hardware system for the new CCD camera. Based on the new system architecture, the control software is re-designed and implemented. The software system adopts the message passing mechanism via WebSocket protocol, and improves its flexibility, expansibility, and scalability. The user interface with responsive web design realizes the remote operating under both desktop and mobile devices. The stable operating of software system has greatly enhanced the operation efficiency while reducing the complexity, and has also made a successful attempt for the future system design of telescope and telescope cloud.

  6. Robust EMG sensing system based on data fusion for myoelectric control of a robotic arm

    PubMed Central

    López, Natalia M; di Sciascio, Fernando; Soria, Carlos M; Valentinuzzi, Max E

    2009-01-01

    Background Myoelectric control of a robotic manipulator may be disturbed by failures due to disconnected electrodes, interface impedance changes caused by movements, problems in the recording channel and other various noise sources. To correct these problems, this paper presents two fusing techniques, Variance Weighted Average (VWA) and Decentralized Kalman Filter (DKF), both based on the myoelectric signal variance as selecting criterion. Methods Tested in five volunteers, a redundant arrangement was obtained with two pairs of electrodes for each recording channel. The myoelectric signals were electronically amplified, filtered and digitalized, while the processing, fusion algorithms and control were implemented in a personal computer under MATLAB® environment and in a Digital Signal Processor (DSP). The experiments used an industrial robotic manipulator BOSCH SR-800, type SCARA, with four degrees of freedom; however, only the first joint was used to move the end effector to a desired position, the latter obtained as proportional to the EMG amplitude. Results Several trials, including disconnecting and reconnecting one electrode and disturbing the signal with synthetic noise, were performed to test the fusion techniques. The results given by VWA and DKF were transformed into joint coordinates and used as command signals to the robotic arm. Even though the resultant signal was not exact, the failure was ignored and the joint reference signal never exceeded the workspace limits. Conclusion The fault robustness and safety characteristics of a myoelectric controlled manipulator system were substantially improved. The proposed scheme prevents potential risks for the operator, the equipment and the environment. Both algorithms showed efficient behavior. This outline could be applied to myoelectric control of prosthesis, or assistive manipulators to better assure the system functionality when electrode faults or noisy environment are present. PMID:19243627

  7. Thermal control systems for low-temperature heat rejection on a lunar base

    NASA Technical Reports Server (NTRS)

    Sridhar, K. R.; Gottmann, Matthias

    1992-01-01

    In this report, Rankine-cycle heat pumps and absorption heat pumps (ammonia-water and lithium bromide-water) have been analyzed and optimized for a lunar base cooling load of 100 kW. For the Rankine cycle, a search of several commonly used commercial refrigerants provided R11 and R717 as possible working fluids. Hence, the Rankine-cycle analysis has been performed for both R11 and R717. Two different configurations were considered for the system--one in which the heat pump is directly connected to the rejection loop and another in which a heat exchanger connects the heat pump to the rejection loop. For a marginal increase in mass, the decoupling of the rejection loop and the radiator from the heat pump provides greater reliability of the system and better control. Hence, the decoupled system is the configuration of choice. The optimal TCS mass for a 100 kW cooling load at 270 K was 5940 kg at a radiator temperature of 362 K. R11 was the working fluid in the heat pump, and R717 was the transport fluid in the rejection loop. Two TCS's based on an absorption-cycle heat pump were considered, one with an ammonia-water mixture and the other with a lithium bromide-water mixture as the working fluid. A complete cycle analysis was performed for these systems. The system components were approximated as heat exchangers with no internal pressure drop for the mass estimate. This simple approach underpredicts the mass of the systems, but is a good 'optimistic' first approximation to the TCS mass in the absence of reliable component mass data. The mass estimates of the two systems reveal that, in spite of this optimistic estimate, the absorption heat pumps are not competitive with the Rankine-cycle heat pumps. Future work at the systems level will involve similar analyses for the Brayton- and Stirling-cycle heat pumps. The analyses will also consider the operation of the pump under partial-load conditions. On the component level, a capillary evaporator will be designed, built

  8. An RFID-based luggage and passenger tracking system for airport security control applications

    NASA Astrophysics Data System (ADS)

    Vastianos, George E.; Kyriazanos, Dimitris M.; Kountouriotis, Vassilios I.; Thomopoulos, Stelios C. A.

    2014-06-01

    Market analysis studies of recent years have shown a steady and significant increase in the usage of RFID technology. Key factors for this growth were the decreased costs of passive RFIDs and their improved performance compared to the other identification technologies. Besides the benefits of RFID technologies into the supply chains, warehousing, traditional inventory and asset management applications, RFID has proven itself worth exploiting on experimental, as well as on commercial level in other sectors, such as healthcare, transport and security. In security sector, airport security is one of the biggest challenges. Airports are extremely busy public places and thus prime targets for terrorism, with aircraft, passengers, crew and airport infrastructure all subject to terrorist attacks. Inside this labyrinth of security challenges, the long range detection capability of the UHF passive RFID technology can be turned into a very important tracking tool that may outperform all the limitations of the barcode tracking inside the current airport security control chain. The Integrated Systems Lab of NCSR Demokritos has developed an RFID based Luggage and Passenger tracking system within the TASS (FP7-SEC-2010-241905) EU research project. This paper describes application scenarios of the system categorized according to the structured nature of the environment, the system architecture and presents evaluation results extracted from measurements with a group of different massive production GEN2 UHF RFID tags that are widely available in the world market.

  9. An endorsement-based approach to student modeling for planner-controlled intelligent tutoring systems

    NASA Technical Reports Server (NTRS)

    Murray, William R.

    1990-01-01

    An approach is described to student modeling for intelligent tutoring systems based on an explicit representation of the tutor's beliefs about the student and the arguments for and against those beliefs (called endorsements). A lexicographic comparison of arguments, sorted according to evidence reliability, provides a principled means of determining those beliefs that are considered true, false, or uncertain. Each of these beliefs is ultimately justified by underlying assessment data. The endorsement-based approach to student modeling is particularly appropriate for tutors controlled by instructional planners. These tutors place greater demands on a student model than opportunistic tutors. Numerical calculi approaches are less well-suited because it is difficult to correctly assign numbers for evidence reliability and rule plausibility. It may also be difficult to interpret final results and provide suitable combining functions. When numeric measures of uncertainty are used, arbitrary numeric thresholds are often required for planning decisions. Such an approach is inappropriate when robust context-sensitive planning decisions must be made. A TMS-based implementation of the endorsement-based approach to student modeling is presented, this approach is compared to alternatives, and a project history is provided describing the evolution of this approach.

  10. The Automated Alert System for the Hospital Infection Control and the Safety of Medical Staff Based on EMR Data.

    PubMed

    Jo, Eunmi

    2016-01-01

    This report is about planning, developing, and implementing the automated alert system for the Hospital infection control and the safety of medical staffs about information on patients exposed to infection based on EMR Data in a tertiary hospital in Korea.

  11. Poly lactic acid based injectable delivery systems for controlled release of a model protein, lysozyme.

    PubMed

    Al-Tahami, Khaled; Meyer, Amanda; Singh, Jagdish

    2006-02-01

    The objective of this study was to evaluate the critical formulation parameters (i.e., polymer concentration, polymer molecular weight, and solvent nature) affecting the controlled delivery of a model protein, lysozyme, from injectable polymeric implants. The conformational stability and biological activity of the released lysozyme were also investigated. Three formulations containing 10%, 20%, and 30% (w/v) poly lactic acid (PLA) in triacetin were investigated. It was found that increasing polymer concentration in the formulations led to a lower burst effect and a slower release rate. Formulation with a high molecular weight polymer showed a greater burst effect as compared to those containing low molecular weight. Conformational stability and biological activity of released samples were studied by differential scanning calorimeter and enzyme activity assay, respectively. The released samples had significantly (P < 0.05) greater conformational stability and biological activity in comparison to the control (lysozyme in buffer solution kept at same conditions). Increasing polymer concentration increased both the conformational stability and the biological activity of released lysozyme. In conclusion, phase sensitive polymer-based delivery systems were able to deliver a model protein, lysozyme, in a conformationally stable and biologically active form at a controlled rate over an extended period.

  12. MFTF supervisory control system

    NASA Astrophysics Data System (ADS)

    1980-12-01

    A computerized supervisory control system is being developed for the Mirror Fusion Test Facility. The system includes nine Perkin-Elmer 7/32 and 8/32 computers connected by a block of common core memory (128 kilobytes). The network is a disk designed for reliability and redundancy. If one computer goes down, the local-control micro-processors that it controls are switched to another computer in a matter of seconds. The control consoles permit operators to open and close valves, start or stop pumps, and adjust operating levels. The experiment is controlled by two superconsoles and five satellite consoles. The software, written in PASCAL, contains such subsystems as organizing the computers into a network, operating the consoles and accessing the data base.

  13. A knowledge-based control system for air-scour optimisation in membrane bioreactors.

    PubMed

    Ferrero, G; Monclús, H; Sancho, L; Garrido, J M; Comas, J; Rodríguez-Roda, I

    2011-01-01

    Although membrane bioreactors (MBRs) technology is still a growing sector, its progressive implementation all over the world, together with great technical achievements, has allowed it to reach a mature degree, just comparable to other more conventional wastewater treatment technologies. With current energy requirements around 0.6-1.1 kWh/m3 of treated wastewater and investment costs similar to conventional treatment plants, main market niche for MBRs can be areas with very high restrictive discharge limits, where treatment plants have to be compact or where water reuse is necessary. Operational costs are higher than for conventional treatments; consequently there is still a need and possibilities for energy saving and optimisation. This paper presents the development of a knowledge-based decision support system (DSS) for the integrated operation and remote control of the biological and physical (filtration and backwashing or relaxation) processes in MBRs. The core of the DSS is a knowledge-based control module for air-scour consumption automation and energy consumption minimisation.

  14. Cryogenic Control System

    SciTech Connect

    Goloborod'ko, S.; /Fermilab

    1989-02-27

    The control system (CS) for the cryogenic arrangement of the DO Liquid Argon Calorimeter consists of a Texas instruments 560/565 Programmable Logical Controller (PLC), two remote bases with Remote Base Controllers and a corresponding set of input/output (I/O) modules, and a PC AST Premium 286 (IBM AT Compatible). The PLC scans a set of inputs and provides a set of outputs based on a ladder logic program and PID control loops. The inputs are logic or analog (current, voltage) signals from equipment status switches or transducers. The outputs are logic or analog (current or voltage) signals for switching solenoids and positioning pneumatic actuators. Programming of the PLC is preformed by using the TISOFT2/560/565 package, which is installed in the PC. The PC communicates to the PLC through a serial RS232 port and provides operator interface to the cryogenic process using Xpresslink software.

  15. A new power regulator control system based on verilog for electrostatic precipitators

    NASA Astrophysics Data System (ADS)

    Zhang, Zisheng; Li, Guan; Liu, Taotao; Ge, Pengbo; Liu, Zhiqiang

    2013-03-01

    In order to improve the inefficient response of the power system in traditional electrostatic precipitators, such as long design cycles and low safety, a new power regulator control system is designed to tackle the deficiencies. The working voltage system of an electrostatic precipitator consists of an L-C component, a rectifier bridge group and a step-up transformer. The Verilog hardware description language is used to complete the design of the feedback systems. Continuous steady current can be obtained automatically through changing the number of steady voltage control units. The results show that control systems can accurately feed back the changes of the voltage signal of the electrostatic precipitator. Comparing with other control systems, it has the advantages of faster response, higher accuracy, better monitoring performance and superior anti-interference capacity.

  16. Experimental study on active vibration control using genetic algorithm-based system identification and optimized positive position feedback

    NASA Astrophysics Data System (ADS)

    Orszulik, Ryan R.; Shan, Jinjun

    2012-12-01

    A genetic algorithm is implemented to identify the transfer function of an experimental system consisting of a flexible manipulator with a collocated piezoelectric sensor/actuator pair. A multi-mode positive position feedback controller is then designed based upon the identified transfer function. To this end, the same iteratively implemented genetic algorithm is used to optimize all controller parameters by minimization of the closed loop H∞-norm. The designed controller is then applied for vibration suppression on the experimental system.

  17. Motion-Based System Identification and Fault Detection and Isolation Technologies for Thruster Controlled Spacecraft

    NASA Technical Reports Server (NTRS)

    Wilson, Edward; Sutter, David W.; Berkovitz, Dustin; Betts, Bradley J.; Kong, Edmund; delMundo, Rommel; Lages, Christopher R.; Mah, Robert W.; Papasin, Richard

    2003-01-01

    By analyzing the motions of a thruster-controlled spacecraft, it is possible to provide on-line (1) thruster fault detection and isolation (FDI), and (2) vehicle mass- and thruster-property identification (ID). Technologies developed recently at NASA Ames have significantly improved the speed and accuracy of these ID and FDI capabilities, making them feasible for application to a broad class of spacecraft. Since these technologies use existing sensors, the improved system robustness and performance that comes with the thruster fault tolerance and system ID can be achieved through a software-only implementation. This contrasts with the added cost, mass, and hardware complexity commonly required by FDI. Originally developed in partnership with NASA - Johnson Space Center to provide thruster FDI capability for the X-38 during re-entry, these technologies are most recently being applied to the MIT SPHERES experimental spacecraft to fly on the International Space Station in 2004. The model-based FDI uses a maximum-likelihood calculation at its core, while the ID is based upon recursive least squares estimation. Flight test results from the SPHERES implementation, as flown aboard the NASA KC-1 35A 0-g simulator aircraft in November 2003 are presented.

  18. Rapidly optimizing an aptamer based BoNT sensor by feedback system control (FSC) scheme.

    PubMed

    Wei, Fang; Bai, Bin; Ho, Chih-Ming

    2011-12-15

    The sensitivity and detection time of an aptamer based biosensor for detecting botulinum neurotoxin (BoNT) depend upon the formation of proper tertiary architecture of aptamer, which closely correlates with the combinatorial effects of multiple types of ions and their concentrations presented in the buffer. Finding the optimal conditions for four different ions at 12 different concentrations, 20,736 possible combinations, by brute force is an extremely laborious and time-consuming task. Here, we introduce a feedback system control (FSC) scheme that can rapidly identify the best combination of components to form the optimal aptamer structure binding to a target molecule. In this study, rapid identification of optimized ionic combinations for electrochemical aptasensor of BoNT type A (BoNT/A) detection has been achieved. Only about 10 iterations with about 50 tests in each iteration are needed to identify the optimal ionic concentration out of the 20,736 possibilities. The most exciting finding was that a very short detection time and high sensitivity could be achieved with the optimized combinational ion buffer. Only a 5-min detection time, compared with hours or even days, was needed for aptamer-based BoNT/A detection with a limit of detection of 40 pg/ml. The methodologies described here can be applied to other multi-parameter chemical systems, which should significantly improve the rate of parameter optimization.

  19. Design and implementation of a low power mobile CPU based embedded system for artificial leg control.

    PubMed

    Hernandez, Robert; Yang, Qing; Huang, He; Zhang, Fan; Zhang, Xiaorong

    2013-01-01

    This paper presents the design and implementation of a new neural-machine-interface (NMI) for control of artificial legs. The requirements of high accuracy, real-time processing, low power consumption, and mobility of the NMI place great challenges on the computation engine of the system. By utilizing the architectural features of a mobile embedded CPU, we are able to implement our decision-making algorithm, based on neuromuscular phase-dependant support vector machines (SVM), with exceptional accuracy and processing speed. To demonstrate the superiority of our NMI, real-time experiments were performed on an able bodied subject with a 20 ms window increment. The 20 ms testing yielded accuracies of 99.94% while executing our algorithm efficiently with less than 11% processor loads.

  20. Virtual Rehabilitation for Multiple Sclerosis Using a Kinect-Based System: Randomized Controlled Trial

    PubMed Central

    Gil-Gómez, Hermenegildo; Gil-Gómez, Jose-Antonio; Albiol-Pérez, Sergio; Palacios-Navarro, Guillermo; Fardoun, Habib M; Mashat, Abdulfattah S

    2014-01-01

    Background The methods used for the motor rehabilitation of patients with neurological disorders include a number of different rehabilitation exercises. For patients who have been diagnosed with multiple sclerosis (MS), the performance of motor rehabilitation exercises is essential. Nevertheless, this rehabilitation may be tedious, negatively influencing patients’ motivation and adherence to treatment. Objective We present RemoviEM, a system based on Kinect that uses virtual reality (VR) and natural user interfaces (NUI) to offer patients with MS an intuitive and motivating way to perform several motor rehabilitation exercises. It offers therapists a new motor rehabilitation tool for the rehabilitation process, providing feedback on the patient’s progress. Moreover, it is a low-cost system, a feature that can facilitate its integration in clinical rehabilitation centers. Methods A randomized and controlled single blinded study was carried out to assess the influence of a Kinect-based virtual rehabilitation system on the balance rehabilitation of patients with MS. This study describes RemoviEM and evaluates its effectiveness compared to standard rehabilitation. To achieve this objective, a clinical trial was carried out. Eleven patients from a MS association participated in the clinical trial. The mean age was 44.82 (SD 10.44) and the mean time from diagnosis (years) was 9.77 (SD 10.40). Clinical effectiveness was evaluated using clinical balance scales. Results Significant group-by-time interaction was detected in the scores of the Berg Balance Scale (P=.011) and the Anterior Reach Test in standing position (P=.011). Post-hoc analysis showed greater improvement in the experimental group for these variables than in the control group for these variables. The Suitability Evaluation Questionnaire (SEQ) showed good results in usability, acceptance, security, and safety for the evaluated system. Conclusions The results obtained suggest that RemoviEM represents a

  1. Exergy Based Analysis for the Environmental Control and Life Support Systems of the International Space Station

    NASA Technical Reports Server (NTRS)

    Clem, Kirk A.; Nelson, George J.; Mesmer, Bryan L.; Watson, Michael D.; Perry, Jay L.

    2016-01-01

    When optimizing the performance of complex systems, a logical area for concern is improving the efficiency of useful energy. The energy available for a system to perform work is defined as a system's energy content. Interactions between a system's subsystems and the surrounding environment can be accounted for by understanding various subsystem energy efficiencies. Energy balance of reactants and products, and enthalpies and entropies, can be used to represent a chemical process. Heat transfer energy represents heat loads, and flow energy represents system flows and filters. These elements allow for a system level energy balance. The energy balance equations are developed for the subsystems of the Environmental Control and Life Support (ECLS) system aboard the International Space Station (ISS). The use of these equations with system information would allow for the calculation of the energy efficiency of the system, enabling comparisons of the ISS ECLS system to other systems as well as allows for an integrated systems analysis for system optimization.

  2. Adaptive back-stepping pitch angle control for wind turbine based on a new electro-hydraulic pitch system

    NASA Astrophysics Data System (ADS)

    Yin, Xiu-xing; Lin, Yong-gang; Li, Wei; Gu, Ya-jing; Lei, Peng-fei; Liu, Hong-wei

    2015-11-01

    A new electro-hydraulic pitch system is proposed to smooth the output power and drive-train torque fluctuations for wind turbine. This new pitch system employs a servo-valve-controlled hydraulic motor to enhance pitch control performances. This pitch system is represented by a state-space model with parametric uncertainties and nonlinearities. An adaptive back-stepping pitch angle controller is synthesised based on this state-space model to accurately achieve the desired pitch angle control regardless of such uncertainties and nonlinearities. This pitch angle controller includes a back-stepping procedure and an adaption law to deal with such uncertainties and nonlinearities and hence to improve the final pitch control performances. The proposed pitch system and the designed pitch angle controller have been validated for achievable and efficient power and torque regulation performances by comparative experimental results under various operating conditions.

  3. Design of a controlled ecological life support system - Regenerative technologies are necessary for implementation in a lunar base CELSS

    NASA Technical Reports Server (NTRS)

    Schwartzkopf, Steven H.

    1992-01-01

    Issues involved in designing a life support system for a new era of space exploration are outlined. A conceptual design is described for a controlled ecological life support system developed for a lunar base. In situ resource utilization for such a system is examined.

  4. Multivariable disturbance observer-based H2 analytical decoupling control design for multivariable systems

    NASA Astrophysics Data System (ADS)

    Zhang, Wei; Wang, Yagang; Liu, Yurong; Zhang, Weidong

    2016-01-01

    In this paper, an H2 analytical decoupling control scheme with multivariable disturbance observer for both stable and unstable multi-input/multi-output (MIMO) systems with multiple time delays is proposed. Compared with conventional control strategies, the main merit is that the proposed control scheme can improve the system performances effectively when the MIMO processes with severe model mismatches and strong external disturbances. Besides, the design method has three additional advantages. First, the derived controller and observer are given in analytical forms, the design procedure is simple. Second, the orders of the designed controller and observer are low, they can be implemented easily in practice. Finally, the performance and robustness can be adjusted easily by tuning the parameters in the designed controller and observer. It is useful for practical application. Simulations are provided to illustrate the effectiveness of the proposed control scheme.

  5. Simulation of the fast steering mirror control system based on gyro velocity feedback

    NASA Astrophysics Data System (ADS)

    Kuang, Jiagming; Tang, Tao; Fu, Chengyu; Ding, Ke; Yu, Wei

    2009-11-01

    The fast steering mirror is a significant element of the photoelectric precision tracking system and is mainly used for attenuating the tracking error of the main axis and rejecting the line-of-sight jitter caused by various disturbances. A control loop model is constructed and object parameters have been identified according to this model in this paper. Low sampling frequency introduce great delay into the imaging tracking system, which may restrict greatly the closed-loop bandwidth, reduce tracking precision of the system and even make the system unsteady. Various elements which limit tracking loop bandwidth are presented and analyzed. Three tracking systems with different sampling frequency are simulated and analyzed. From the simulation result the conclusion can be drawn that it is difficult to increase the closedloop bandwidth in the presence of great delay by means of the general control method. Accordingly feedback control or feed forward control may be tried to improve the error attenuation of the system. The micro-mechanical gyro can be used for measuring the angular velocity of fast steering mirror, so output of velocity gyro as velocity loop feedback may improve the system performance. Furthermore, the velocity loop feedback can enhance the rigidity and the output stability of the tracking system. Finally, the velocity feedback can increase the type of the open loop system; consequently it will improve the error attenuation of the system. The simulation result shows that the tracking precision of the system with velocity feedback is 10 times better than the system without velocity feedback.

  6. H-infinity mix sensitivity controller design based on GIMC for electro-optical stabilization and tracking system

    NASA Astrophysics Data System (ADS)

    Liu, Zi-dong; Bao, Qi-liang; Xia, Yunxia; Liu, Xiang

    2013-08-01

    Electro-optical stabilization and tracking system is critical and difficult issue in satellite laser communication. Moreover, line-of-sight stabilized system is the kernel of implementing electro-optical stabilization and tracking system, which can be used to isolate the vibration of the moving platform of the satellite and the disturbance of the space environment. In this paper, we propose a new method, which using H∞ mix sensitivity based on generalized internal model controller (GIMC), to design the control system of the electro-optical stabilized platform. It is well known that there is an intrinsic conflict between performance and robustness in the standard feedback framework. Generalized internal model controller is a new architecture which can separate the performance and robustness design in controller design. This architecture has two parts: a high performance controller, say K0,which is designed by PI controller in this paper, and then a robustification controller, say Q, which is designed to improve the ability of the anti disturbance by using H-infinity mix sensitivity controller design method. In this paper, we also present the steps of controller design by using this method to make it easier to use. Based on the proposed method, numerical simulation and experiment are both carried out for a gyro stabilized platform of electro-optical tacking system. Both the numerical simulated and the experimental results show that the electro-optical stabilized platform using the H-infinity mix sensitivity controller design method based on GIMC is accurate and effective. Comparing with the same PI controller in standard feedback framework, the proposed method can guarantee the high tracking performance as same as the PI controller and improve the external disturbance restraining ability a lot. In conclusion, H-infinity mix sensitivity controller design method based on GIMC is a new approach for gyro stabilized platform of electro-optical stabilization and tracking

  7. Direct power control of DFIG wind turbine systems based on an intelligent proportional-integral sliding mode control.

    PubMed

    Li, Shanzhi; Wang, Haoping; Tian, Yang; Aitouch, Abdel; Klein, John

    2016-09-01

    This paper presents an intelligent proportional-integral sliding mode control (iPISMC) for direct power control of variable speed-constant frequency wind turbine system. This approach deals with optimal power production (in the maximum power point tracking sense) under several disturbance factors such as turbulent wind. This controller is made of two sub-components: (i) an intelligent proportional-integral module for online disturbance compensation and (ii) a sliding mode module for circumventing disturbance estimation errors. This iPISMC method has been tested on FAST/Simulink platform of a 5MW wind turbine system. The obtained results demonstrate that the proposed iPISMC method outperforms the classical PI and intelligent proportional-integral control (iPI) in terms of both active power and response time.

  8. Direct power control of DFIG wind turbine systems based on an intelligent proportional-integral sliding mode control.

    PubMed

    Li, Shanzhi; Wang, Haoping; Tian, Yang; Aitouch, Abdel; Klein, John

    2016-09-01

    This paper presents an intelligent proportional-integral sliding mode control (iPISMC) for direct power control of variable speed-constant frequency wind turbine system. This approach deals with optimal power production (in the maximum power point tracking sense) under several disturbance factors such as turbulent wind. This controller is made of two sub-components: (i) an intelligent proportional-integral module for online disturbance compensation and (ii) a sliding mode module for circumventing disturbance estimation errors. This iPISMC method has been tested on FAST/Simulink platform of a 5MW wind turbine system. The obtained results demonstrate that the proposed iPISMC method outperforms the classical PI and intelligent proportional-integral control (iPI) in terms of both active power and response time. PMID:27346331

  9. Adaptive Fuzzy Tracking Control of Nonlinear Systems With Asymmetric Actuator Backlash Based on a New Smooth Inverse.

    PubMed

    Lai, Guanyu; Liu, Zhi; Zhang, Yun; Philip Chen, C L

    2016-06-01

    This paper is concentrated on the problem of adaptive fuzzy tracking control for an uncertain nonlinear system whose actuator is encountered by the asymmetric backlash behavior. First, we propose a new smooth inverse model which can approximate the asymmetric actuator backlash arbitrarily. By applying it, two adaptive fuzzy control scenarios, namely, the compensation-based control scheme and nonlinear decomposition-based control scheme, are then developed successively. It is worth noticing that the first fuzzy controller exhibits a better tracking control performance, although it recourses to a known slope ratio of backlash nonlinearity. The second one further removes the restriction, and also gets a desirable control performance. By the strict Lyapunov argument, both adaptive fuzzy controllers guarantee that the output tracking error is convergent to an adjustable region of zero asymptotically, while all the signals remain semiglobally uniformly ultimately bounded. Lastly, two comparative simulations are conducted to verify the effectiveness of the proposed fuzzy controllers. PMID:27187937

  10. An LQG based PSS design for controlling the SSR in power systems with series-compensated lines

    SciTech Connect

    Seo, J.C.; Kim, T.H.; Park, J.K.; Moon, S.I.

    1996-06-01

    This paper presents a linear quadratic Gaussian (LQG) based power system stabilizer (PSS) to control the subsynchronous resonance (SSR) that may occur in a series capacitor compensated power system. This paper investigates the dominant parameters on the SSR using the critical compensation level (CCL), and selects the design parameters to confirm the stability robustness. The complete SSR simulation system based on the IEEE first benchmark is employed in this study. Eigenvalue analysis and time domain simulations using a nonlinear system model show that the proposed PSS can control the SSR efficiently.

  11. A Digitalized Gyroscope System Based on a Modified Adaptive Control Method.

    PubMed

    Xia, Dunzhu; Hu, Yiwei; Ni, Peizhen

    2016-03-04

    In this work we investigate the possibility of applying the adaptive control algorithm to Micro-Electro-Mechanical System (MEMS) gyroscopes. Through comparing the gyroscope working conditions with the reference model, the adaptive control method can provide online estimation of the key parameters and the proper control strategy for the system. The digital second-order oscillators in the reference model are substituted for two phase locked loops (PLLs) to achieve a more steady amplitude and frequency control. The adaptive law is modified to satisfy the condition of unequal coupling stiffness and coupling damping coefficient. The rotation mode of the gyroscope system is considered in our work and a rotation elimination section is added to the digitalized system. Before implementing the algorithm in the hardware platform, different simulations are conducted to ensure the algorithm can meet the requirement of the angular rate sensor, and some of the key adaptive law coefficients are optimized. The coupling components are detected and suppressed respectively and Lyapunov criterion is applied to prove the stability of the system. The modified adaptive control algorithm is verified in a set of digitalized gyroscope system, the control system is realized in digital domain, with the application of Field Programmable Gate Array (FPGA). Key structure parameters are measured and compared with the estimation results, which validated that the algorithm is feasible in the setup. Extra gyroscopes are used in repeated experiments to prove the commonality of the algorithm.

  12. A Digitalized Gyroscope System Based on a Modified Adaptive Control Method.

    PubMed

    Xia, Dunzhu; Hu, Yiwei; Ni, Peizhen

    2016-01-01

    In this work we investigate the possibility of applying the adaptive control algorithm to Micro-Electro-Mechanical System (MEMS) gyroscopes. Through comparing the gyroscope working conditions with the reference model, the adaptive control method can provide online estimation of the key parameters and the proper control strategy for the system. The digital second-order oscillators in the reference model are substituted for two phase locked loops (PLLs) to achieve a more steady amplitude and frequency control. The adaptive law is modified to satisfy the condition of unequal coupling stiffness and coupling damping coefficient. The rotation mode of the gyroscope system is considered in our work and a rotation elimination section is added to the digitalized system. Before implementing the algorithm in the hardware platform, different simulations are conducted to ensure the algorithm can meet the requirement of the angular rate sensor, and some of the key adaptive law coefficients are optimized. The coupling components are detected and suppressed respectively and Lyapunov criterion is applied to prove the stability of the system. The modified adaptive control algorithm is verified in a set of digitalized gyroscope system, the control system is realized in digital domain, with the application of Field Programmable Gate Array (FPGA). Key structure parameters are measured and compared with the estimation results, which validated that the algorithm is feasible in the setup. Extra gyroscopes are used in repeated experiments to prove the commonality of the algorithm. PMID:26959019

  13. A Digitalized Gyroscope System Based on a Modified Adaptive Control Method

    PubMed Central

    Xia, Dunzhu; Hu, Yiwei; Ni, Peizhen

    2016-01-01

    In this work we investigate the possibility of applying the adaptive control algorithm to Micro-Electro-Mechanical System (MEMS) gyroscopes. Through comparing the gyroscope working conditions with the reference model, the adaptive control method can provide online estimation of the key parameters and the proper control strategy for the system. The digital second-order oscillators in the reference model are substituted for two phase locked loops (PLLs) to achieve a more steady amplitude and frequency control. The adaptive law is modified to satisfy the condition of unequal coupling stiffness and coupling damping coefficient. The rotation mode of the gyroscope system is considered in our work and a rotation elimination section is added to the digitalized system. Before implementing the algorithm in the hardware platform, different simulations are conducted to ensure the algorithm can meet the requirement of the angular rate sensor, and some of the key adaptive law coefficients are optimized. The coupling components are detected and suppressed respectively and Lyapunov criterion is applied to prove the stability of the system. The modified adaptive control algorithm is verified in a set of digitalized gyroscope system, the control system is realized in digital domain, with the application of Field Programmable Gate Array (FPGA). Key structure parameters are measured and compared with the estimation results, which validated that the algorithm is feasible in the setup. Extra gyroscopes are used in repeated experiments to prove the commonality of the algorithm. PMID:26959019

  14. Systems and methods for providing power to a load based upon a control strategy

    DOEpatents

    Perisic, Milun; Lawrence, Christopher P; Ransom, Ray M; Kajouke, Lateef A

    2014-11-04

    Systems and methods are provided for an electrical system. The electrical system, for example, includes a first load, an interface configured to receive a voltage from a voltage source, and a controller configured to receive the voltage through the interface and to provide a voltage and current to the first load. The controller may be further configured to, receive information on a second load electrically connected to the voltage source, determine an amount of reactive current to return to the voltage source such that a current drawn by the electrical system and the second load from the voltage source is substantially real, and provide the determined reactive current to the voltage source.

  15. Feedback control system based on a remote operated PID controller implemented using mbed NXP LPC1768 development board

    NASA Astrophysics Data System (ADS)

    Pricop, Emil; Zamfir, Florin; Paraschiv, Nicolae

    2015-11-01

    Process control is a challenging research topic for both academia and industry for a long time. Controllers evolved from the classical SISO approach to modern fuzzy or neuro-fuzzy embedded devices with networking capabilities, however PID algorithms are still used in the most industrial control loops. In this paper, we focus on the implementation of a PID controller using mbed NXP LPC1768 development board. This board integrates a powerful ARM Cortex- M3 core and has networking capabilities. The implemented controller can be remotely operated by using an Internet connection and a standard Web browser. The main advantages of the proposed embedded system are customizability, easy operation and very low power consumption. The experimental results obtained by using a simulated process are analysed and shows that the implementation can be done with success in industrial applications.

  16. Summary of Research on Reliability Criteria-Based Flight System Control

    NASA Technical Reports Server (NTRS)

    Wu, N. Eva; Belcastro, Christine (Technical Monitor)

    2002-01-01

    This paper presents research on the reliability assessment of adaptive flight control systems. The topics include: 1) Overview of Project Focuses; 2) Reliability Analysis; and 3) Design for Reliability. This paper is presented in viewgraph form.

  17. Manipulation based on sensor-directed control: An integrated end effector and touch sensing system

    NASA Technical Reports Server (NTRS)

    Hill, J. W.; Sword, A. J.

    1973-01-01

    A hand/touch sensing system is described that, when mounted on a position-controlled manipulator, greatly expands the kinds of automated manipulation tasks that can be undertaken. Because of the variety of coordinate conversions, control equations, and completion criteria, control is necessarily dependent upon a small digital computer. The sensing system is designed both to be rugged and to sense the necessary touch and force information required to execute a wide range of manipulation tasks. The system consists of a six-axis wrist sensor, external touch sensors, and a pair of matrix jaw sensors. Details of the construction of the particular sensors, the integration of the end effector into the sensor system, and the control algorithms for using the sensor outputs to perform manipulation tasks automatically are discussed.

  18. On the delay effects of different channels in Internet-based networked control systems

    NASA Astrophysics Data System (ADS)

    Zhao, Yun-Bo; Kim, Jongrae; Sun, Xi-Ming; Liu, Guo-Ping

    2013-11-01

    The sensor-to-controller and the controller-to-actuator delays in networked control systems (NCSs) are investigated for the first time with respect to their different effects on the system performance. This study starts with identifying the delay-independent and delay-dependent control laws in NCSs, and confirms that only two delay-dependent control laws can cause different delay effects in different channels. The conditions under which the different delays in different channels can cause different effects are then given for both delay-dependent control laws. The results are verified by numerical examples. Potentially, these results can be regarded as important design principles in the practical implementation of NCSs.

  19. Telerobot control system

    NASA Technical Reports Server (NTRS)

    Backes, Paul G. (Inventor); Tso, Kam S. (Inventor)

    1993-01-01

    This invention relates to an operator interface for controlling a telerobot to perform tasks in a poorly modeled environment and/or within unplanned scenarios. The telerobot control system includes a remote robot manipulator linked to an operator interface. The operator interface includes a setup terminal, simulation terminal, and execution terminal for the control of the graphics simulator and local robot actuator as well as the remote robot actuator. These terminals may be combined in a single terminal. Complex tasks are developed from sequential combinations of parameterized task primitives and recorded teleoperations, and are tested by execution on a graphics simulator and/or local robot actuator, together with adjustable time delays. The novel features of this invention include the shared and supervisory control of the remote robot manipulator via operator interface by pretested complex tasks sequences based on sequences of parameterized task primitives combined with further teleoperation and run-time binding of parameters based on task context.

  20. Network-Based Output Tracking Control for a Class of T-S Fuzzy Systems That Can Not Be Stabilized by Nondelayed Output Feedback Controllers.

    PubMed

    Zhang, Dawei; Han, Qing-Long; Jia, Xinchun

    2015-08-01

    This paper investigates network-based output tracking control for a T-S fuzzy system that can not be stabilized by a nondelayed fuzzy static output feedback controller, but can be stabilized by a delayed fuzzy static output feedback controller. By intentionally introducing a communication network that produces proper network-induced delays in the feedback control loop, a stable and satisfactory tracking control can be ensured for the T-S fuzzy system. Due to the presence of network-induced delays, the fuzzy system and the fuzzy tracking controller operate in an asynchronous way. Taking the asynchronous operation and network-induced delays into consideration, the network-based tracking control system is modeled as an asynchronous T-S fuzzy system with an interval time-varying delay. A new delay-dependent criterion for L2 -gain tracking performance is derived by using the deviation bounds of asynchronous normalized membership functions and a complete Lyapunov-Krasovskii functional. Applying a particle swarm optimization technique with the feasibility of the derived criterion, a novel design algorithm is presented to determine the minimum L2 -gain tracking performance and control gains simultaneously. The effectiveness of the proposed method is illustrated by performing network-based output tracking control of a Duffing-Van der Pol's oscillator. PMID:25222965

  1. Design and evaluation of osmotic pump-based controlled release system of Ambroxol Hydrochloride.

    PubMed

    Cheng, Xiongkai; Sun, Min; Gao, Yan; Cao, Fengliang; Zhai, Guangxi

    2011-08-01

    The purpose of the present study was to design and evaluate an osmotic pump-based drug delivery system for controlling the release of Ambroxol Hydrochloride (Amb). Citric acid, lactose and polyethylene glycol 6000 (PEG 6000) were employed as osmotic agents. Surelease EC containing polyethylene glycol 400 (PEG 400) controlling the membrane porosity was used as semi-permeable membrane. The formulation of tablet core was optimized by orthogonal design and evaluated by weighted mark method. The influences of the amount of PEG 400 and membrane thickness on Amb release were investigated. The optimal osmotic pump tablet (OPT) was evaluated in different release media and at different stirring rates. The major release power confirmed was osmotic pressure. The release of Amb from OPT was verified at a rate of approximately zero-order, and cumulative release percentage at 12?h was 92.6%. The relative bioavailability of Amb OPT in rabbits relative to the commercial sustained capsule was 109.6%. Our results showed that Amb OPT could be a practical preparation with a good prospect.

  2. Control Synthesis for a Class of Hybrid Systems Subject to Configuration-Based Safety Constraints

    NASA Technical Reports Server (NTRS)

    Heymann, Michael; Lin, Feng; Meyer, George

    1997-01-01

    We examine a class of hybrid systems which we call Composite Hybrid Machines (CHM's) that consists of the concurrent (and partially synchronized) operation of Elementary Hybrid Machines (EHM's). Legal behavior, specified by a set of illegal configurations that the CHM may not enter, is to be achieved by the concurrent operation of the CHM with a suitably designed legal controller. In the present paper we focus on the problem of synthesizing a legal controller, whenever such a controller exists. More specifically, we address the problem of synthesizing the minimally restrictive legal controller. A controller is minimally restrictive if, when composed to operate concurrently with another legal controller, it will never interfere with the operation of the other controller and, therefore, can be composed to operate concurrently with any other controller that may be designed to achieve liveness specifications or optimality requirements without the need to reinvestigate or reverify legality of the composite controller. We confine our attention to a special class of CHM's where system dynamics is rate-limited and legal guards are conjunctions or disjunctions of atomic formulas in the dynamic variables (of the type x less than or equal to x(sub 0), or x greater than or equal to x(sub 0)). We present an algorithm for synthesis of the minimally restrictive legal controller. We demonstrate our approach by synthesizing a minimally restrictive controller for a steam boiler (the verification of which recently received a great deal of attention).

  3. Development of a PC-based data acquisition and control system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An inexpensive data acquisition and control system was developed, which can easily be used with different computers for many agricultural and biological applications. The high-speed data acquisition and control device uses only an RS-232 serial port to interface with a PC. The device has two analo...

  4. Sliding mode based fault detection, reconstruction and fault tolerant control scheme for motor systems.

    PubMed

    Mekki, Hemza; Benzineb, Omar; Boukhetala, Djamel; Tadjine, Mohamed; Benbouzid, Mohamed

    2015-07-01

    The fault-tolerant control problem belongs to the domain of complex control systems in which inter-control-disciplinary information and expertise are required. This paper proposes an improved faults detection, reconstruction and fault-tolerant control (FTC) scheme for motor systems (MS) with typical faults. For this purpose, a sliding mode controller (SMC) with an integral sliding surface is adopted. This controller can make the output of system to track the desired position reference signal in finite-time and obtain a better dynamic response and anti-disturbance performance. But this controller cannot deal directly with total system failures. However an appropriate combination of the adopted SMC and sliding mode observer (SMO), later it is designed to on-line detect and reconstruct the faults and also to give a sensorless control strategy which can achieve tolerance to a wide class of total additive failures. The closed-loop stability is proved, using the Lyapunov stability theory. Simulation results in healthy and faulty conditions confirm the reliability of the suggested framework.

  5. Observed-Based Adaptive Fuzzy Tracking Control for Switched Nonlinear Systems With Dead-Zone.

    PubMed

    Tong, Shaocheng; Sui, Shuai; Li, Yongming

    2015-12-01

    In this paper, the problem of adaptive fuzzy output-feedback control is investigated for a class of uncertain switched nonlinear systems in strict-feedback form. The considered switched systems contain unknown nonlinearities, dead-zone, and immeasurable states. Fuzzy logic systems are utilized to approximate the unknown nonlinear functions, a switched fuzzy state observer is designed and thus the immeasurable states are obtained by it. By applying the adaptive backstepping design principle and the average dwell time method, an adaptive fuzzy output-feedback tracking control approach is developed. It is proved that the proposed control approach can guarantee that all the variables in the closed-loop system are bounded under a class of switching signals with average dwell time, and also that the system output can track a given reference signal as closely as possible. The simulation results are given to check the effectiveness of the proposed approach.

  6. Permanent magnet synchronous motor servo system control based on μC/OS

    NASA Astrophysics Data System (ADS)

    Shi, Chongyang; Chen, Kele; Chen, Xinglong

    2015-10-01

    When Opto-Electronic Tracking system operates in complex environments, every subsystem must operate efficiently and stably. As a important part of Opto-Electronic Tracking system, the performance of PMSM(Permanent Magnet Synchronous Motor) servo system affects the Opto-Electronic Tracking system's accuracy and speed greatly[1][2]. This paper applied embedded real-time operating system μC/OS to the control of PMSM servo system, implemented SVPWM(Space Vector Pulse Width Modulation) algorithm in PMSM servo system, optimized the stability of PMSM servo system. Pointing on the characteristics of the Opto-Electronic Tracking system, this paper expanded μC/OS with software redundancy processes, remote debugging and upgrading. As a result, the Opto- Electronic Tracking system performs efficiently and stably.

  7. Supporting Ease-of-Use and User Control: Desired Features and Structure of Web-Based Online IR Systems.

    ERIC Educational Resources Information Center

    Xie, Hong

    2003-01-01

    Describes a study that investigated users' perceptions of ease of use versus user control in Web-based online information retrieval (IR) systems. Discusses desired features and functionalities as well as desired interface structures that support both ease of use and user control. (Author/LRW)

  8. Adaptive gain control for spike-based map communication in a neuromorphic vision system.

    PubMed

    Meng, Yicong; Shi, Bertram E

    2008-06-01

    To support large numbers of model neurons, neuromorphic vision systems are increasingly adopting a distributed architecture, where different arrays of neurons are located on different chips or processors. Spike-based protocols are used to communicate activity between processors. The spike activity in the arrays depends on the input statistics as well as internal parameters such as time constants and gains. In this paper, we investigate strategies for automatically adapting these parameters to maintain a constant firing rate in response to changes in the input statistics. We find that under the constraint of maintaining a fixed firing rate, a strategy based upon updating the gain alone performs as well as an optimal strategy where both the gain and the time constant are allowed to vary. We discuss how to choose the time constant and propose an adaptive gain control mechanism whose operation is robust to changes in the input statistics. Our experimental results on a mobile robotic platform validate the analysis and efficacy of the proposed strategy.

  9. A new reduction-based LQ control for dynamic systems with a slowly time-varying delay

    NASA Astrophysics Data System (ADS)

    Liu, Bo; Haraguchi, Masakazu; Hu, Haiyan

    2009-08-01

    Time delays in the feedback control often deteriorate the control performance or even cause the instability of a dynamic system. This paper presents a control strategy for the dynamic system with a constant or a slowly time-varying input delay based on a transformation, which simplifies the time-delay system into a delay-free one. Firstly, the relation is discussed for two existing reduction-based linear quadratic controls. One is continuous and the other is discrete. By extending the relation, a new reduction-based control is then developed with a numerical algorithm presented for practical control implementation. The controller suggested by the proposed method has such a promising property that it can be used for the cases of different values of an input time delay without redesign of controller. This property provides the potential for stabilizing the dynamic system with a time-varying input delay. Consequently, the application of the proposed method to the dynamic system with a slowly time-varying delay is discussed. Finally, numerical simulations are given to show the efficacy and the applicability of the method.

  10. MCMAC-cVT: a novel on-line associative memory based CVT transmission control system.

    PubMed

    Ang, K K; Quek, C; Wahab, A

    2002-03-01

    This paper describes a novel application of an associative memory called the Modified Cerebellar Articulation Controller (MCMAC) (Int. J. Artif. Intell. Engng, 10 (1996) 135) in a continuous variable transmission (CVT) control system. It allows the on-line tuning of the associative memory and produces an effective gain-schedule for the automatic selection of the CVT gear ratio. Various control algorithms are investigated to control the CVT gear ratio to maintain the engine speed within a narrow range of efficient operating speed independently of the vehicle velocity. Extensive simulation results are presented to evaluate the control performance of a direct digital PID control algorithm with auto-tuning (Trans. ASME, 64 (1942)) and anti-windup mechanism. In particular, these results are contrasted against the control performance produced using the MCMAC (Int. J. Artif. Intell. Engng, 10 (1996) 135) with momentum, neighborhood learning and Averaged Trapezoidal Output (MCMAC-ATO) as the neural control algorithm for controlling the CVT. Simulation results are presented that show the reduced control fluctuations and improved learning capability of the MCMAC-ATO without incurring greater memory requirement. In particular, MCMAC-ATO is able to learn and control the CVT simultaneously while still maintaining acceptable control performance. PMID:12022510

  11. MCMAC-cVT: a novel on-line associative memory based CVT transmission control system.

    PubMed

    Ang, K K; Quek, C; Wahab, A

    2002-03-01

    This paper describes a novel application of an associative memory called the Modified Cerebellar Articulation Controller (MCMAC) (Int. J. Artif. Intell. Engng, 10 (1996) 135) in a continuous variable transmission (CVT) control system. It allows the on-line tuning of the associative memory and produces an effective gain-schedule for the automatic selection of the CVT gear ratio. Various control algorithms are investigated to control the CVT gear ratio to maintain the engine speed within a narrow range of efficient operating speed independently of the vehicle velocity. Extensive simulation results are presented to evaluate the control performance of a direct digital PID control algorithm with auto-tuning (Trans. ASME, 64 (1942)) and anti-windup mechanism. In particular, these results are contrasted against the control performance produced using the MCMAC (Int. J. Artif. Intell. Engng, 10 (1996) 135) with momentum, neighborhood learning and Averaged Trapezoidal Output (MCMAC-ATO) as the neural control algorithm for controlling the CVT. Simulation results are presented that show the reduced control fluctuations and improved learning capability of the MCMAC-ATO without incurring greater memory requirement. In particular, MCMAC-ATO is able to learn and control the CVT simultaneously while still maintaining acceptable control performance.

  12. A new LabVIEW-based control system for the Naval Research Laboratory Trace Element Accelerator Mass Spectrometer

    SciTech Connect

    DeTurck, T. M.; Treacy, D. J. Jr.; Knies, D. L.; Grabowski, K. S.; Knoll, C.; Kennedy, C. A.; Hubler, G. K.

    1999-06-10

    A new LabVIEW-based control system for the existing tandem accelerator and new AMS components has been implemented at the Trace Element Accelerator Mass Spectrometry (TEAMS) facility at the Naval Research Laboratory. Through the use of Device Interfaces (DIs) distributed along a fiber optic network, virtually every component of the accelerator system can be controlled from any networked computer terminal as well as remotely via modem or the internet. This paper discusses the LabVIEW-based control software, including remote operation, automatic calculation of ion optical component parameters, beam optimization, and data logging and retrieval.

  13. Piezoelectric-hydraulic pump based band brake actuation system for automotive transmission control

    NASA Astrophysics Data System (ADS)

    Kim, Gi-Woo; Wang, K. W.

    2007-04-01

    The actuation system of friction elements (such as band brakes) is essential for high quality operations in modern automotive automatic transmissions (in short, ATs). The current band brake actuation system consists of several hydraulic components, including the oil pump, the regulating valve and the control valves. In general, it has been recognized that the current AT band brake actuation system has many limitations. For example, the oil pump and valve body are relatively heavy and complex. Also, the oil pumps induce inherently large drag torque, which affects fuel economy. This research is to overcome these problems of the current system by exploring the utilization of a hybrid type piezo-hydraulic pump device for AT band brake control. This new actuating system integrates a piezo-hydraulic pump to the input of the band brake. Compared with the current systems, this new actuator features much simpler structure, smaller size, and lower weight. This paper describes the development, design and fabrication of the new stand-alone prototype actuator for AT band brake control. An analytical model is developed and validated using experimental data. Performance tests on the hardware and system simulations utilizing the validated model are performed to characterize the new prototype actuator. It is predicted that with increasing of accumulator pressure and driving frequency, the proposed prototype actuating system will satisfy the band brake requirement for AT shift control.

  14. FUZZY LOGIC BASED INTELLIGENT CONTROL OF A VARIABLE SPEED CAGE MACHINE WIND GENERATION SYSTEM

    EPA Science Inventory

    The paper describes a variable-speed wind generation system where fuzzy logic principles are used to optimize efficiency and enhance performance control. A squirrel cage induction generator feeds the power to a double-sided pulse width modulated converter system which either pump...

  15. Achieving control and interoperability through unified model-based systems and software engineering

    NASA Technical Reports Server (NTRS)

    Rasmussen, Robert; Ingham, Michel; Dvorak, Daniel

    2005-01-01

    Control and interoperation of complex systems is one of the most difficult challenges facing NASA's Exploration Systems Mission Directorate. An integrated but diverse array of vehicles, habitats, and supporting facilities, evolving over the long course of the enterprise, must perform ever more complex tasks while moving steadily away from the sphere of ground support and intervention.

  16. Integrated flight/propulsion control system design based on a decentralized, hierarchical approach

    NASA Technical Reports Server (NTRS)

    Mattern, Duane; Garg, Sanjay; Bullard, Randy

    1989-01-01

    A sample integrated flight/propulsion control system design is presented for the piloted longitiudinal landing task with a modern, statistically unstable fighter aircraft. The design procedure is summarized, the vehicle model used in the sample study is described, and the procedure for partitioning the integrated system is presented along with a description of the subsystems. The high-level airframe performance specifications and control design are presented and the control performance is evaluated. The generation of the low-level (engine) subsystem specifications from the airframe requirements are discussed, and the engine performance specifications are presented along with the subsystem control design. A compensator to accommodate the influence of airframe outputs on the engine subsystem is also considered. Finally, the entire closed loop system performance and stability characteristics are examined.

  17. Lattice hydrodynamic model based traffic control: A transportation cyber-physical system approach

    NASA Astrophysics Data System (ADS)

    Liu, Hui; Sun, Dihua; Liu, Weining

    2016-11-01

    Lattice hydrodynamic model is a typical continuum traffic flow model, which describes the jamming transition of traffic flow properly. Previous studies in lattice hydrodynamic model have shown that the use of control method has the potential to improve traffic conditions. In this paper, a new control method is applied in lattice hydrodynamic model from a transportation cyber-physical system approach, in which only one lattice site needs to be controlled in this control scheme. The simulation verifies the feasibility and validity of this method, which can ensure the efficient and smooth operation of the traffic flow.

  18. Fuzzy chaos control for vehicle lateral dynamics based on active suspension system

    NASA Astrophysics Data System (ADS)

    Huang, Chen; Chen, Long; Jiang, Haobin; Yuan, Chaochun; Xia, Tian

    2014-07-01

    The existing research of the active suspension system (ASS) mainly focuses on the different evaluation indexes and control strategies. Among the different components, the nonlinear characteristics of practical systems and control are usually not considered for vehicle lateral dynamics. But the vehicle model has some shortages on tyre model with side-slip angle, road adhesion coefficient, vertical load and velocity. In this paper, the nonlinear dynamic model of lateral system is considered and also the adaptive neural network of tire is introduced. By nonlinear analysis methods, such as the bifurcation diagram and Lyapunov exponent, it has shown that the lateral dynamics exhibits complicated motions with the forward speed. Then, a fuzzy control method is applied to the lateral system aiming to convert chaos into periodic motion using the linear-state feedback of an available lateral force with changing tire load. Finally, the rapid control prototyping is built to conduct the real vehicle test. By comparison of time response diagram, phase portraits and Lyapunov exponents at different work conditions, the results on step input and S-shaped road indicate that the slip angle and yaw velocity of lateral dynamics enter into stable domain and the results of test are consistent to the simulation and verified the correctness of simulation. And the Lyapunov exponents of the closed-loop system are becoming from positive to negative. This research proposes a fuzzy control method which has sufficient suppress chaotic motions as an effective active suspension system.

  19. Neural Flight Control System

    NASA Technical Reports Server (NTRS)

    Gundy-Burlet, Karen

    2003-01-01

    The Neural Flight Control System (NFCS) was developed to address the need for control systems that can be produced and tested at lower cost, easily adapted to prototype vehicles and for flight systems that can accommodate damaged control surfaces or changes to aircraft stability and control characteristics resulting from failures or accidents. NFCS utilizes on a neural network-based flight control algorithm which automatically compensates for a broad spectrum of unanticipated damage or failures of an aircraft in flight. Pilot stick and rudder pedal inputs are fed into a reference model which produces pitch, roll and yaw rate commands. The reference model frequencies and gains can be set to provide handling quality characteristics suitable for the aircraft of interest. The rate commands are used in conjunction with estimates of the aircraft s stability and control (S&C) derivatives by a simplified Dynamic Inverse controller to produce virtual elevator, aileron and rudder commands. These virtual surface deflection commands are optimally distributed across the aircraft s available control surfaces using linear programming theory. Sensor data is compared with the reference model rate commands to produce an error signal. A Proportional/Integral (PI) error controller "winds up" on the error signal and adds an augmented command to the reference model output with the effect of zeroing the error signal. In order to provide more consistent handling qualities for the pilot, neural networks learn the behavior of the error controller and add in the augmented command before the integrator winds up. In the case of damage sufficient to affect the handling qualities of the aircraft, an Adaptive Critic is utilized to reduce the reference model frequencies and gains to stay within a flyable envelope of the aircraft.

  20. Auto Code Generation for Simulink-Based Attitude Determination Control System

    NASA Technical Reports Server (NTRS)

    MolinaFraticelli, Jose Carlos

    2012-01-01

    This paper details the work done to auto generate C code from a Simulink-Based Attitude Determination Control System (ADCS) to be used in target platforms. NASA Marshall Engineers have developed an ADCS Simulink simulation to be used as a component for the flight software of a satellite. This generated code can be used for carrying out Hardware in the loop testing of components for a satellite in a convenient manner with easily tunable parameters. Due to the nature of the embedded hardware components such as microcontrollers, this simulation code cannot be used directly, as it is, on the target platform and must first be converted into C code; this process is known as auto code generation. In order to generate C code from this simulation; it must be modified to follow specific standards set in place by the auto code generation process. Some of these modifications include changing certain simulation models into their atomic representations which can bring new complications into the simulation. The execution order of these models can change based on these modifications. Great care must be taken in order to maintain a working simulation that can also be used for auto code generation. After modifying the ADCS simulation for the auto code generation process, it is shown that the difference between the output data of the former and that of the latter is between acceptable bounds. Thus, it can be said that the process is a success since all the output requirements are met. Based on these results, it can be argued that this generated C code can be effectively used by any desired platform as long as it follows the specific memory requirements established in the Simulink Model.

  1. Effect of bonding on the performance of a piezoactuator-based active control system

    NASA Technical Reports Server (NTRS)

    Baz, A.; Poh, S.

    1987-01-01

    The utilization of piezoelectric actuators in controlling the structural vibrations of flexible beams is studied. A Modified Independent Modal Space Control (MIMSC) method is devised to select the optimal location, control gains and excitation voltage of the piezoelectric actuators in a way that would minimize the amplitudes of vibrations of beams to which these actuators are bonded, as well as the input control energy necessary to suppress these vibrations. The presented method accounts for the effects that the piezoelectric actuators and the bonding layers have on changing the elastic and inertial properties of the flexible beams. Numerical examples are presented to illustrate the application of the MIMSC method and to demonstrate the effect of the physical and geometrical properties of the bonding layer on the dynamic performance of the actively controlled beams. The obtained results emphasize the importance of the devised method in designing more realistic active control systems for flexible beams, in particular, and large flexible structures in general.

  2. Neural network-based adaptive consensus tracking control for multi-agent systems under actuator faults

    NASA Astrophysics Data System (ADS)

    Zhao, Lin; Jia, Yingmin

    2016-06-01

    In this paper, a distributed output feedback consensus tracking control scheme is proposed for second-order multi-agent systems in the presence of uncertain nonlinear dynamics, external disturbances, input constraints, and partial loss of control effectiveness. The proposed controllers incorporate reduced-order filters to account for the unmeasured states, and the neural networks technique is implemented to approximate the uncertain nonlinear dynamics in the synthesis of control algorithms. In order to compensate the partial loss of actuator effectiveness faults, fault-tolerant parts are included in controllers. Using the Lyapunov approach and graph theory, it is proved that the controllers guarantee a group of agents that simultaneously track a common time-varying state of leader, even when the state of leader is available only to a subset of the members of a group. Simulation results are provided to demonstrate the effectiveness of the proposed consensus tracking method.

  3. Identification and control of nonlinear system based on Laguerre-ELM Wiener model

    NASA Astrophysics Data System (ADS)

    Tang, Yinggan; Han, Zhenzhen; Liu, Fucai; Guan, Xinping

    2016-09-01

    In this paper, a new Wiener model is presented for identification and control of single-input single-output (SISO) nonlinear systems. The proposed Wiener model consists of a linear Laguerre filter in cascaded with an extreme learning machine (ELM) neural network (called Laguerre-ELM Wiener model). Laguerre filter can approximate a stable linear system to any degree of accuracy with a small number of Laguerre filters, which provides a parsimony structure and high level accuracy simultaneously. To determine the appropriated number of Laguerre filters in Laguerre-ELM Wiener model, Lipschitz quotient criterion is adapted to determine the order of linear part. A generalized ELM algorithm is proposed to estimate the parameters of Laguerre-ELM Wiener model. Once the unknown nonlinear system is identified using Laguerre-ELM Wiener model, a generalized predictive control (GPC) algorithm is designed for control of nonlinear system. The advantage of the proposed control method is that it transfers a nonlinear control problem to a linear one by inserting the inverse of static nonlinear section. Simulation results demonstrate the effectiveness of the proposed identification and control algorithms.

  4. International Space Station Sustaining Engineering: A Ground-Based Test Bed for Evaluating Integrated Environmental Control and Life Support System and Internal Thermal Control System Flight Performance

    NASA Technical Reports Server (NTRS)

    Ray, Charles D.; Perry, Jay L.; Callahan, David M.

    2000-01-01

    As the International Space Station's (ISS) various habitable modules are placed in service on orbit, the need to provide for sustaining engineering becomes increasingly important to ensure the proper function of critical onboard systems. Chief among these are the Environmental Control and Life Support System (ECLSS) and the Internal Thermal Control System (ITCS). Without either, life onboard the ISS would prove difficult or nearly impossible. For this reason, a ground-based ECLSS/ITCS hardware performance simulation capability has been developed at NASA's Marshall Space Flight Center. The ECLSS/ITCS Sustaining Engineering Test Bed will be used to assist the ISS Program in resolving hardware anomalies and performing periodic performance assessments. The ISS flight configuration being simulated by the test bed is described as well as ongoing activities related to its preparation for supporting ISS Mission 5A. Growth options for the test facility are presented whereby the current facility may be upgraded to enhance its capability for supporting future station operation well beyond Mission 5A. Test bed capabilities for demonstrating technology improvements of ECLSS hardware are also described.

  5. Uncertainty-based competition between prefrontal and dorsolateral striatal systems for behavioral control.

    PubMed

    Daw, Nathaniel D; Niv, Yael; Dayan, Peter

    2005-12-01

    A broad range of neural and behavioral data suggests that the brain contains multiple systems for behavioral choice, including one associated with prefrontal cortex and another with dorsolateral striatum. However, such a surfeit of control raises an additional choice problem: how to arbitrate between the systems when they disagree. Here, we consider dual-action choice systems from a normative perspective, using the computational theory of reinforcement learning. We identify a key trade-off pitting computational simplicity against the flexible and statistically efficient use of experience. The trade-off is realized in a competition between the dorsolateral striatal and prefrontal systems. We suggest a Bayesian principle of arbitration between them according to uncertainty, so each controller is deployed when it should be most accurate. This provides a unifying account of a wealth of experimental evidence about the factors favoring dominance by either system.

  6. Optimal control strategy design based on dynamic programming for a dual-motor coupling-propulsion system.

    PubMed

    Zhang, Shuo; Zhang, Chengning; Han, Guangwei; Wang, Qinghui

    2014-01-01

    A dual-motor coupling-propulsion electric bus (DMCPEB) is modeled, and its optimal control strategy is studied in this paper. The necessary dynamic features of energy loss for subsystems is modeled. Dynamic programming (DP) technique is applied to find the optimal control strategy including upshift threshold, downshift threshold, and power split ratio between the main motor and auxiliary motor. Improved control rules are extracted from the DP-based control solution, forming near-optimal control strategies. Simulation results demonstrate that a significant improvement in reducing energy loss due to the dual-motor coupling-propulsion system (DMCPS) running is realized without increasing the frequency of the mode switch.

  7. Robust design of feedback feed-forward iterative learning control based on 2D system theory for linear uncertain systems

    NASA Astrophysics Data System (ADS)

    Li, Zhifu; Hu, Yueming; Li, Di

    2016-08-01

    For a class of linear discrete-time uncertain systems, a feedback feed-forward iterative learning control (ILC) scheme is proposed, which is comprised of an iterative learning controller and two current iteration feedback controllers. The iterative learning controller is used to improve the performance along the iteration direction and the feedback controllers are used to improve the performance along the time direction. First of all, the uncertain feedback feed-forward ILC system is presented by an uncertain two-dimensional Roesser model system. Then, two robust control schemes are proposed. One can ensure that the feedback feed-forward ILC system is bounded-input bounded-output stable along time direction, and the other can ensure that the feedback feed-forward ILC system is asymptotically stable along time direction. Both schemes can guarantee the system is robust monotonically convergent along the iteration direction. Third, the robust convergent sufficient conditions are given, which contains a linear matrix inequality (LMI). Moreover, the LMI can be used to determine the gain matrix of the feedback feed-forward iterative learning controller. Finally, the simulation results are presented to demonstrate the effectiveness of the proposed schemes.

  8. Optimal control-based states transfer for non-Markovian quantum system

    NASA Astrophysics Data System (ADS)

    Ying-Hua, Ji; Ju-ju, Hu; Jian-Hua, Huang; Qiang, Ke

    2016-07-01

    Utilizing the method of optimal control, we investigate the tactics of state transfer in the non-Markovian quantum system with phase relaxation and energy dissipative relaxation. The influence of Ohmic reservoir with Lorentz-Drude regularization is numerically studied. Owing to the decoherence and memory effects of non-Markovian channel, the purity of quantum state attenuates damply in the free evolution. The numerical simulations indicate that arbitrary state transfer for non-Markovian system can be realized under the optimal control function by a proper external control field with a success rate of more than 98 percent. When the right control field and function is implemented, not only the decoherence is compensated completely but also the purity of quantum states are maintained in the process of state transfer.

  9. Towards an Irritable Bowel Syndrome Control System Based on Artificial Neural Networks

    NASA Astrophysics Data System (ADS)

    Podolski, Ina; Rettberg, Achim

    To solve health problems with medical applications that use complex algorithms is a trend nowadays. It could also be a chance to help patients with critical problems caused from nerve irritations to overcome them and provide a better living situation. In this paper a system for monitoring and controlling the nerves from the intestine is described on a theoretical basis. The presented system could be applied to the irritable bowel syndrome. For control a neural network is used. The advantages for using a neural network for the control of irritable bowel syndrome are the adaptation and learning. These two aspects are important because the syndrome behavior varies from patient to patient and have also concerning the time a lot of variations with respect to each patient. The developed neural network is implemented and can be simulated. Therefore, it can be shown how the network monitor and control the nerves for individual input parameters.

  10. From Concept-to-Flight: An Active Active Fluid Loop Based Thermal Control System for Mars Science Laboratory Rover

    NASA Technical Reports Server (NTRS)

    Birur, Gajanana C.; Bhandari, Pradeep; Bame, David; Karlmann, Paul; Mastropietro, A. J.; Liu, Yuanming; Miller, Jennifer; Pauken, Michael; Lyra, Jacqueline

    2012-01-01

    The Mars Science Laboratory (MSL) rover, Curiosity, which was launched on November 26, 2011, incorporates a novel active thermal control system to keep the sensitive electronics and science instruments at safe operating and survival temperatures. While the diurnal temperature variations on the Mars surface range from -120 C to +30 C, the sensitive equipment are kept within -40 C to +50 C. The active thermal control system is based on a single-phase mechanically pumped fluid loop (MPFL) system which removes or recovers excess waste heat and manages it to maintain the sensitive equipment inside the rover at safe temperatures. This paper will describe the entire process of developing this active thermal control system for the MSL rover from concept to flight implementation. The development of the rover thermal control system during its architecture, design, fabrication, integration, testing, and launch is described.

  11. Adaptive control based on fast online algebraic identification and GPI control for magnetic levitation systems with time-varying input gain

    NASA Astrophysics Data System (ADS)

    Morales, R.; Sira-Ramírez, H.; Feliu, V.

    2014-08-01

    This paper considers the position tracking problem of a voltage-controlled magnetic levitation system (MLS) in the presence of modelling errors caused by uncertainties in the system's physical parameters. An adaptive control based on fast online algebraic parameter estimation and generalised proportional integral (GPI) output feedback control is considered as a control scheme candidate. The GPI controller guarantees an asymptotically exponentially stable behaviour of the controlled ball position and the possibilities of carrying out rest-to-rest trajectory tracking tasks. The nature of the control input gain in an MLS is that of a state-dependent time-varying gain, reflecting the nonlinear character of the magnetic force with regard to the distance and the properties of the metallic ball. The system gain has therefore been locally approximated using a periodically updated time polynomial function (of second degree), where the coefficients of the polynomial are estimated during a very short period of time. This estimation is achieved using the recently introduced algebraic online parameter estimation approach. The stability of the closed-loop system is demonstrated under the assumption that no external factors cause changes in the parameter during the time interval in which the stability is analysed. Finally, experimental results are presented for the controlled MLS demonstrating the excellent stabilisation and position tracking performance of the control system designed in the presence of significant nonlinearities and uncertainties of the underlying system.

  12. The environmental control and life-support system for a lunar base: What drives its design

    NASA Technical Reports Server (NTRS)

    Hypes, Warren D.; Hall, John B., Jr.

    1992-01-01

    The purpose of this paper is to identify and briefly discuss some of the ground rules and mission scenario details that become drivers of the environmental control and life support (ECLS) system design and of the logistics related to the design. This paper is written for mission planners and non-ECLS system engineers to inform them of the details that will be important to the ECLS engineer when the design phase is reached. In addition, examples illustrate the impact of some selected mission characteristics on the logistics associated with ECLS systems. The last section of this paper focuses on the ECLS system technology development sequence and highlights specific portions that need emphasis.

  13. A Randomized Controlled Study of a Web Based Performance Improvement System for Substance Abuse Treatment Providers

    PubMed Central

    Crits-Christoph, Paul; Ring-Kurtz, Sarah; McClure, Bridget; Temes, Christina; Kulaga, Agatha; Gallop, Robert; Forman, Robert; Rotrosen, John

    2010-01-01

    We report here on the results of a randomized, controlled trial evaluating the efficacy of a semi-automated performance improvement system (“Patient Feedback”) that enables real-time monitoring of patient outcomes in outpatient substance abuse treatment clinics. The study involved 118 clinicians working at 20 community-based outpatient substance abuse treatment clinics in the northeast United States. Ten clinics received 12 weeks of the Patient Feedback performance improvement intervention and ten clinics received no intervention during the 12 weeks. Over 1500 patients provided anonymous ratings of therapeutic alliance, treatment satisfaction, and drug/alcohol use. There was no evidence of an intervention effect on the primary drug and alcohol use scales. There was also no evidence of an intervention effect on secondary measures of therapeutic alliance. Clinician-rated measures of organizational functioning and job satisfaction also showed no intervention effect. Possible insights from these findings, and alternative methods of utilizing feedback reports to enhance clinical outcomes are proposed. PMID:20116964

  14. Measuring barometric pressure with a manifold pressure sensor in a microprocessor based engine control system

    SciTech Connect

    Pauwels, M.A.; Wright, D.O.

    1986-07-15

    A microprocessor based electronic engine control system is described for an internal combustion engine, a method for updating the stored ambient pressure signal by measuring the ambient barometric pressure during engine operation using a manifold pressure sensor. The method consists of: generating timing signals indicating the rotational position of an engine member and including a signal indicating a predetermined rotational position in the rotation of the engine member; generating a pressure signal from the manifold pressure sensor representing the pressure surrounding the sensor in response to the predetermined rotational position; reading the value of ambient barometric pressure stored in the memory of the microprocessor; comparing the value of the barometric pressure stored in the memory of the microprocessor and the value of the pressure signal; increasing the value of the barometric pressure by one unit to generate a new barometric pressure value when the value of the pressure signal is greater than the value of the barometric pressure; comparing the new barometric pressure value with a predetermined fixed constant representing the maximum barometric pressure; and storing in the memory of the microprocessor either the new barometric pressure value if equal to or less than the fixed constant or the value of the maximum barometric pressure if the new barometric pressure value is greater than the fixed constant.

  15. Reliability of unstable periodic orbit based control strategies in biological systems.

    PubMed

    Mishra, Nagender; Hasse, Maria; Biswal, B; Singh, Harinder P

    2015-04-01

    Presence of recurrent and statistically significant unstable periodic orbits (UPOs) in time series obtained from biological systems is now routinely used as evidence for low dimensional chaos. Extracting accurate dynamical information from the detected UPO trajectories is vital for successful control strategies that either aim to stabilize the system near the fixed point or steer the system away from the periodic orbits. A hybrid UPO detection method from return maps that combines topological recurrence criterion, matrix fit algorithm, and stringent criterion for fixed point location gives accurate and statistically significant UPOs even in the presence of significant noise. Geometry of the return map, frequency of UPOs visiting the same trajectory, length of the data set, strength of the noise, and degree of nonstationarity affect the efficacy of the proposed method. Results suggest that establishing determinism from unambiguous UPO detection is often possible in short data sets with significant noise, but derived dynamical properties are rarely accurate and adequate for controlling the dynamics around these UPOs. A repeat chaos control experiment on epileptic hippocampal slices through more stringent control strategy and adaptive UPO tracking is reinterpreted in this context through simulation of similar control experiments on an analogous but stochastic computer model of epileptic brain slices. Reproduction of equivalent results suggests that far more stringent criteria are needed for linking apparent success of control in such experiments with possible determinism in the underlying dynamics.

  16. Reliability of unstable periodic orbit based control strategies in biological systems

    SciTech Connect

    Mishra, Nagender; Singh, Harinder P.; Hasse, Maria; Biswal, B.

    2015-04-15

    Presence of recurrent and statistically significant unstable periodic orbits (UPOs) in time series obtained from biological systems is now routinely used as evidence for low dimensional chaos. Extracting accurate dynamical information from the detected UPO trajectories is vital for successful control strategies that either aim to stabilize the system near the fixed point or steer the system away from the periodic orbits. A hybrid UPO detection method from return maps that combines topological recurrence criterion, matrix fit algorithm, and stringent criterion for fixed point location gives accurate and statistically significant UPOs even in the presence of significant noise. Geometry of the return map, frequency of UPOs visiting the same trajectory, length of the data set, strength of the noise, and degree of nonstationarity affect the efficacy of the proposed method. Results suggest that establishing determinism from unambiguous UPO detection is often possible in short data sets with significant noise, but derived dynamical properties are rarely accurate and adequate for controlling the dynamics around these UPOs. A repeat chaos control experiment on epileptic hippocampal slices through more stringent control strategy and adaptive UPO tracking is reinterpreted in this context through simulation of similar control experiments on an analogous but stochastic computer model of epileptic brain slices. Reproduction of equivalent results suggests that far more stringent criteria are needed for linking apparent success of control in such experiments with possible determinism in the underlying dynamics.

  17. Reliability of unstable periodic orbit based control strategies in biological systems.

    PubMed

    Mishra, Nagender; Hasse, Maria; Biswal, B; Singh, Harinder P

    2015-04-01

    Presence of recurrent and statistically significant unstable periodic orbits (UPOs) in time series obtained from biological systems is now routinely used as evidence for low dimensional chaos. Extracting accurate dynamical information from the detected UPO trajectories is vital for successful control strategies that either aim to stabilize the system near the fixed point or steer the system away from the periodic orbits. A hybrid UPO detection method from return maps that combines topological recurrence criterion, matrix fit algorithm, and stringent criterion for fixed point location gives accurate and statistically significant UPOs even in the presence of significant noise. Geometry of the return map, frequency of UPOs visiting the same trajectory, length of the data set, strength of the noise, and degree of nonstationarity affect the efficacy of the proposed method. Results suggest that establishing determinism from unambiguous UPO detection is often possible in short data sets with significant noise, but derived dynamical properties are rarely accurate and adequate for controlling the dynamics around these UPOs. A repeat chaos control experiment on epileptic hippocampal slices through more stringent control strategy and adaptive UPO tracking is reinterpreted in this context through simulation of similar control experiments on an analogous but stochastic computer model of epileptic brain slices. Reproduction of equivalent results suggests that far more stringent criteria are needed for linking apparent success of control in such experiments with possible determinism in the underlying dynamics. PMID:25933652

  18. Design of PID Fuzzy Controller for Electric Vehicle Brake Control System Based on Parallel Structure of PI Fuzzy and PD Fuzzy

    NASA Astrophysics Data System (ADS)

    Sugisaka, Masanori; Mbaïtiga, Zacharie

    There exist several problems in the control of vehicle brake including the development of control logic for anti-lock braking system (ABS), base-braking and intelligent braking. Here we study the intelligent braking control where we seek to develop a controller that can ensure that the braking torque commended by the driver will be achieved. In particular, we develop, a new PID Fuzzy controller (PIDFC) based on parallel operation of PI Fuzzy and PD Fuzzy control. Two fuzzy rule bases are constructed by separating the linguistic control rule for PID Fuzzy control into two parts: The first part is e-Δe and the second part is Δ2e-Δe respectively. Then two Fuzzy controls employing these rules bases individually are synthesized and run in parallel. The incremental control input is determined by taking weighted mean of the outputs of two Fuzzy controls. The result, which proves the merit of the proposed method are compared to those found in the previous research.

  19. TOPOLOGY FOR A DSP BASED BEAM CONTROL SYSTEM IN THE AGS BOOSTER.

    SciTech Connect

    DELONG,J.BRENNAN,J.M.HAYES,T.LE,T.N.SMITH,K.

    2003-05-12

    The AGS Booster supports beams of ions and protons with a wide range of energies on a pulse-by-pulse modulation basis. This requires an agile beam control system highly integrated with its controls. To implement this system digital techniques in the form of Digital Signal Processors, Direct Digital Synthesizers, digital receivers and high speed Analog to Digital Converters are used. Signals from the beam and cavity pick-ups, as well as measurements of magnetic field strength in the ring dipoles are processed in real time. To facilitate this a multi-processor topology with high bandwidth data links is being designed.

  20. Software Development for a CompactRIO-Based Wire Scanner Control and Data Acquisition SYstem

    SciTech Connect

    Sedillo, James Daniel

    2012-05-16

    The Beam Diagnostics and Instrumentation Team at the Los Alamos Neutron Science Center is developing a wire scanner data acquisition and control system with a National Instrument's compactRIO at its core. For this application, the compactRIO controller not only requires programming the FPGA and RT computer internal to the compactRIO, but also requires programming a client computer and a touch panel display. This article will summarize the hardware interfaces and describe the software design approach utilized for programming and interfacing the four systems together in order to fulfill the design requirements and promote reliable interoperability.

  1. Realization of Intelligent Measurement and Control System for Limb Rehabilitation Based on PLC and Touch Screen

    NASA Astrophysics Data System (ADS)

    Liu, Xiangquan

    According to the treatment needs of patients with limb movement disorder, on the basis of the limb rehabilitative training prototype, function of measure and control system are analyzed, design of system hardware and software is completed. The touch screen which is adopt as host computer and man-machine interaction window is responsible for sending commands and training information display; The PLC which is adopt as slave computer is responsible for receiving control command from touch screen, collecting the sensor data, regulating torque and speed of motor by analog output according to the different training mode, realizing ultimately active and passive training for limb rehabilitation therapy.

  2. Architectures and Evaluation for Adjustable Control Autonomy for Space-Based Life Support Systems

    NASA Technical Reports Server (NTRS)

    Malin, Jane T.; Schreckenghost, Debra K.

    2001-01-01

    In the past five years, a number of automation applications for control of crew life support systems have been developed and evaluated in the Adjustable Autonomy Testbed at NASA's Johnson Space Center. This paper surveys progress on an adjustable autonomous control architecture for situations where software and human operators work together to manage anomalies and other system problems. When problems occur, the level of control autonomy can be adjusted, so that operators and software agents can work together on diagnosis and recovery. In 1997 adjustable autonomy software was developed to manage gas transfer and storage in a closed life support test. Four crewmembers lived and worked in a chamber for 91 days, with both air and water recycling. CO2 was converted to O2 by gas processing systems and wheat crops. With the automation software, significantly fewer hours were spent monitoring operations. System-level validation testing of the software by interactive hybrid simulation revealed problems both in software requirements and implementation. Since that time, we have been developing multi-agent approaches for automation software and human operators, to cooperatively control systems and manage problems. Each new capability has been tested and demonstrated in realistic dynamic anomaly scenarios, using the hybrid simulation tool.

  3. A rule-based expert system for automatic control rod pattern generation for boiling water reactors

    SciTech Connect

    Lin, L.S.; Lin, C. )

    1991-07-01

    This paper reports on an expert system for generating control rod patterns that has been developed. The knowledge is transformed into IF-THEN rules. The inference engine uses the Rete pattern matching algorithm to match facts, and rule premises and conflict resolution strategies to make the system function intelligently. A forward-chaining mechanism is adopted in the inference engine. The system is implemented in the Common Lisp programming language. The three-dimensional core simulation model performs the core status and burnup calculations. The system is successfully demonstrated by generating control rod programming for the 2894-MW (thermal) Kuosheng nuclear power plant in Taiwan. The computing time is tremendously reduced compared to programs using mathematical methods.

  4. Nation-Wide, Web-Based, Geographic Information System for the Integrated Surveillance and Control of Dengue Fever in Mexico

    PubMed Central

    Hernández-Ávila, Juan Eugenio; Rodríguez, Mario-Henry; Santos-Luna, René; Sánchez-Castañeda, Veronica; Román-Pérez, Susana; Ríos-Salgado, Víctor Hugo; Salas-Sarmiento, Jesús Alberto

    2013-01-01

    Dengue fever incidence and its geographical distribution are increasing throughout the world. Quality and timely information is essential for its prevention and control. A web based, geographically enabled, dengue integral surveillance system (Dengue-GIS) was developed for the nation-wide collection, integration, analysis and reporting of geo-referenced epidemiologic, entomologic, and control interventions data. Consensus in the design and practical operation of the system was a key factor for its acceptance. Working with information systems already implemented as a starting point facilitated its acceptance by officials and operative personnel. Dengue-GIS provides the geographical detail needed to plan, asses and evaluate the impact of control activities. The system is beginning to be adopted as a knowledge base by vector control programs. It is used to generate evidence on impact and cost-effectiveness of control activities, promoting the use of information for decision making at all levels of the vector control program. Dengue-GIS has also been used as a hypothesis generator for the academic community. This GIS-based model system for dengue surveillance and the experience gathered during its development and implementation could be useful in other dengue endemic countries and extended to other infectious or chronic diseases. PMID:23936394

  5. Nation-wide, web-based, geographic information system for the integrated surveillance and control of dengue fever in Mexico.

    PubMed

    Hernández-Ávila, Juan Eugenio; Rodríguez, Mario-Henry; Santos-Luna, René; Sánchez-Castañeda, Veronica; Román-Pérez, Susana; Ríos-Salgado, Víctor Hugo; Salas-Sarmiento, Jesús Alberto

    2013-01-01

    Dengue fever incidence and its geographical distribution are increasing throughout the world. Quality and timely information is essential for its prevention and control. A web based, geographically enabled, dengue integral surveillance system (Dengue-GIS) was developed for the nation-wide collection, integration, analysis and reporting of geo-referenced epidemiologic, entomologic, and control interventions data. Consensus in the design and practical operation of the system was a key factor for its acceptance. Working with information systems already implemented as a starting point facilitated its acceptance by officials and operative personnel. Dengue-GIS provides the geographical detail needed to plan, asses and evaluate the impact of control activities. The system is beginning to be adopted as a knowledge base by vector control programs. It is used to generate evidence on impact and cost-effectiveness of control activities, promoting the use of information for decision making at all levels of the vector control program. Dengue-GIS has also been used as a hypothesis generator for the academic community. This GIS-based model system for dengue surveillance and the experience gathered during its development and implementation could be useful in other dengue endemic countries and extended to other infectious or chronic diseases.

  6. Stability analysis of autonomous space systems in the presence of large disturbances: A Lyapunov-based constrained control strategy.

    PubMed

    Mazinan, A H

    2016-03-01

    The research addresses a Lyapunov-based constrained control strategy to deal with the autonomous space system in the presence of large disturbances. The aforementioned autonomous space system under control is first represented through a dynamics model and subsequently the proposed control strategy is fully investigated with a focus on the three-axis detumbling and the corresponding pointing mode control approaches. The three-axis detumbling mode control approach is designed to deal with the unwanted angular rates of the system to be zero, while the saturations of the actuators are taken into consideration. Moreover, the three-axis pointing mode control approach is designed in the similar state to deal with the rotational angles of the system to be desirable. The contribution of the research is mathematically made to propose a control law in connection with a new candidate of Lyapunov function to deal with the rotational angles and the related angular rates of the present autonomous space system with respect to state-of-the-art. A series of experiments are carried out to consider the efficiency of the proposed control strategy, as long as a number of benchmarks are realized in the same condition to verify and guarantee the strategy performance in both modes of control approaches. PMID:26850751

  7. An Adaptive Coordinated Control for an Offshore Wind Farm Connected VSC Based Multi-Terminal DC Transmission System

    NASA Astrophysics Data System (ADS)

    Kumar, M. Ajay; Srikanth, N. V.

    2014-11-01

    The voltage source converter (VSC) based multiterminal high voltage direct current (MTDC) transmission system is an interesting technical option to integrate offshore wind farms with the onshore grid due to its unique performance characteristics and reduced power loss via extruded DC cables. In order to enhance the reliability and stability of the MTDC system, an adaptive neuro fuzzy inference system (ANFIS) based coordinated control design has been addressed in this paper. A four terminal VSC-MTDC system which consists of an offshore wind farm and oil platform is implemented in MATLAB/ SimPowerSystems software. The proposed model is tested under different fault scenarios along with the converter outage and simulation results show that the novel coordinated control design has great dynamic stabilities and also the VSC-MTDC system can supply AC voltage of good quality to offshore loads during the disturbances.

  8. Neuro-fuzzy controller of low head hydropower plants using adaptive-network based fuzzy inference system

    SciTech Connect

    Djukanovic, M.B.; Calovic, M.S.; Vesovic, B.V.; Sobajic, D.J.

    1997-12-01

    This paper presents an attempt of nonlinear, multivariable control of low-head hydropower plants, by using adaptive-network based fuzzy inference system (ANFIS). The new design technique enhances fuzzy controllers with self-learning capability for achieving prescribed control objectives in a near optimal manner. The controller has flexibility for accepting more sensory information, with the main goal to improve the generator unit transients, by adjusting the exciter input, the wicket gate and runner blade positions. The developed ANFIS controller whose control signals are adjusted by using incomplete on-line measurements, can offer better damping effects to generator oscillations over a wide range of operating conditions, than conventional controllers. Digital simulations of hydropower plant equipped with low-head Kaplan turbine are performed and the comparisons of conventional excitation-governor control, state-feedback optimal control and ANFIS based output feedback control are presented. To demonstrate the effectiveness of the proposed control scheme and the robustness of the acquired neuro-fuzzy controller, the controller has been implemented on a complex high-order non-linear hydrogenerator model.

  9. A nonlinear control method based on ANFIS and multiple models for a class of SISO nonlinear systems and its application.

    PubMed

    Zhang, Yajun; Chai, Tianyou; Wang, Hong

    2011-11-01

    This paper presents a novel nonlinear control strategy for a class of uncertain single-input and single-output discrete-time nonlinear systems with unstable zero-dynamics. The proposed method combines adaptive-network-based fuzzy inference system (ANFIS) with multiple models, where a linear robust controller, an ANFIS-based nonlinear controller and a switching mechanism are integrated using multiple models technique. It has been shown that the linear controller can ensure the boundedness of the input and output signals and the nonlinear controller can improve the dynamic performance of the closed loop system. Moreover, it has also been shown that the use of the switching mechanism can simultaneously guarantee the closed loop stability and improve its performance. As a result, the controller has the following three outstanding features compared with existing control strategies. First, this method relaxes the assumption of commonly-used uniform boundedness on the unmodeled dynamics and thus enhances its applicability. Second, since ANFIS is used to estimate and compensate the effect caused by the unmodeled dynamics, the convergence rate of neural network learning has been increased. Third, a "one-to-one mapping" technique is adapted to guarantee the universal approximation property of ANFIS. The proposed controller is applied to a numerical example and a pulverizing process of an alumina sintering system, respectively, where its effectiveness has been justified.

  10. Generalized hamilton-jacobi-bellman formulation -based neural network control of affine nonlinear discrete-time systems.

    PubMed

    Chen, Zheng; Jagannathan, Sarangapani

    2008-01-01

    In this paper, we consider the use of nonlinear networks towards obtaining nearly optimal solutions to the control of nonlinear discrete-time (DT) systems. The method is based on least squares successive approximation solution of the generalized Hamilton-Jacobi-Bellman (GHJB) equation which appears in optimization problems. Successive approximation using the GHJB has not been applied for nonlinear DT systems. The proposed recursive method solves the GHJB equation in DT on a well-defined region of attraction. The definition of GHJB, pre-Hamiltonian function, HJB equation, and method of updating the control function for the affine nonlinear DT systems under small perturbation assumption are proposed. A neural network (NN) is used to approximate the GHJB solution. It is shown that the result is a closed-loop control based on an NN that has been tuned a priori in offline mode. Numerical examples show that, for the linear DT system, the updated control laws will converge to the optimal control, and for nonlinear DT systems, the updated control laws will converge to the suboptimal control. PMID:18269941

  11. The environmental control and life support system for a lunar base - What drives its design

    NASA Technical Reports Server (NTRS)

    Hypes, Warren D.; Hall, John B., Jr.

    1988-01-01

    It is noted that no single ECLSS is uniquely applicable to a mission of given crew size and duration; all mission parameters, together with details of other systems, must accordingly be factored into the lunar base ECLSS design process that is presently discussed. Experience to date with ECLSS design tasks indicates that mission planners and systems engineers should refrain from emphasizing the 'closed loop' aspects of such systems, since even the best regenerative processes will involve expendable materials that must be resupplied; resupply logistics will accordingly constitute a considerable effort of lunar base operation. Technology development status for processes and subsystems is identified as a major ECLSS design driver.

  12. Development and Flight Testing of a Neural Network Based Flight Control System on the NF-15B Aircraft

    NASA Technical Reports Server (NTRS)

    Bomben, Craig R.; Smolka, James W.; Bosworth, John T.; Silliams-Hayes, Peggy S.; Burken, John J.; Larson, Richard R.; Buschbacher, Mark J.; Maliska, Heather A.

    2006-01-01

    The Intelligent Flight Control System (IFCS) project at the NASA Dryden Flight Research Center, Edwards AFB, CA, has been investigating the use of neural network based adaptive control on a unique NF-15B test aircraft. The IFCS neural network is a software processor that stores measured aircraft response information to dynamically alter flight control gains. In 2006, the neural network was engaged and allowed to learn in real time to dynamically alter the aircraft handling qualities characteristics in the presence of actual aerodynamic failure conditions injected into the aircraft through the flight control system. The use of neural network and similar adaptive technologies in the design of highly fault and damage tolerant flight control systems shows promise in making future aircraft far more survivable than current technology allows. This paper will present the results of the IFCS flight test program conducted at the NASA Dryden Flight Research Center in 2006, with emphasis on challenges encountered and lessons learned.

  13. MEMS based pumped liquid cooling systems for micro/nano spacecraft thermal control

    NASA Technical Reports Server (NTRS)

    Birur, G. C.; Shakkottai, P.; Sur, T. W.

    2000-01-01

    The electronic and other payload power densities in future micro/nano spacecraft are expected to exceed 25 Watts/cm(sup 2) and require advanced thermal control concepts and technologies to keep their payload within allowable temperature limits. This paper presents background on the need for pumped liquid cooling systems for future micro/nano spacecraft and results from this ongoing experimental investigation.

  14. FUZZY LOGIC BASED INTELLIGENT CONTROL OF A VARIABLE SPEED CAGE MACHINE WIND GENERATION SYSTEM

    EPA Science Inventory

    The report gives results of a demonstration of the successful application of fuzzy logic to enhance the performance and control of a variable-speed wind generation system. A squirrel cage induction generator feeds the power to either a double-sided pulse-width modulation converte...

  15. Accounting for Teamwork: A Critical Study of Group-Based Systems of Organizational Control.

    ERIC Educational Resources Information Center

    Ezzamel, Mahmoud; Willmott, Hugh

    1998-01-01

    Examines the role of accounting calculations in reorganizing manufacturing capabilities of a vertically integrated global retailing company. Introducing teamwork to replace line work extended traditional, hierarchical management control systems. Teamwork's self-managing demands contravened workers' established sense of self-identity as…

  16. An arduino based control system for a brackish water desalination plant

    NASA Astrophysics Data System (ADS)

    Caraballo, Ginna

    Water scarcity for agriculture is one of the most important challenges to improve food security worldwide. In this thesis we study the potential to develop a low-cost controller for a small scale brackish desalination plant that consists of proven water treatment technologies, reverse osmosis, cation exchange, and nanofiltration to treat groundwater into two final products: drinking water and irrigation water. The plant is powered by a combination of wind and solar power systems. The low-cost controller uses Arduino Mega, and Arduino DUE, which consist of ATmega2560 and Atmel SAM3X8E ARM Cortex-M3 CPU microcontrollers. These are widely used systems characterized for good performance and low cost. However, Arduino also requires drivers and interfaces to allow the control and monitoring of sensors and actuators. The thesis explains the process, as well as the hardware and software implemented.

  17. A program to evaluate a control system based on feedback of aerodynamic pressure differentials

    NASA Technical Reports Server (NTRS)

    Levy, D. W.; Finn, P.; Roskam, J.

    1981-01-01

    The use of aerodynamic pressure differentials to position a control surface is evaluated. The system is a differential pressure command loop, analogous to a position command loop, where the surface is commanded to move until a desired differential pressure across the surface is achieved. This type of control is more direct and accurate because it is the differential pressure which causes the control forces and moments. A frequency response test was performed in a low speed wind tunnel to measure the performance of the system. Both pressure and position feedback were tested. The pressure feedback performed as well as position feedback implying that the actuator, with a break frequency on the order of 10 Rad/sec, was the limiting component. Theoretical considerations indicate that aerodynamic lags will not appear below frequencies of 50 Rad/sec, or higher.

  18. ISABELLE control system

    SciTech Connect

    Humphrey, J W; Frankel, R S; Niederer, J A

    1980-01-01

    Design principles for the Brookhaven ISABELLE control intersecting storage ring accelerator are described. Principal features include a locally networked console and control computer complex, a system wide process data highway, and intelligent local device controllers. Progress to date is summarized.

  19. Control System Damps Vibrations

    NASA Technical Reports Server (NTRS)

    Kopf, E. H., Jr.; Brown, T. K.; Marsh, E. L.

    1983-01-01

    New control system damps vibrations in rotating equipment with help of phase-locked-loop techniques. Vibrational modes are controlled by applying suitable currents to drive motor. Control signals are derived from sensors mounted on equipment.

  20. An observer based approach for achieving fault diagnosis and fault tolerant control of systems modeled as hybrid Petri nets.

    PubMed

    Renganathan, K; Bhaskar, VidhyaCharan

    2011-07-01

    In this paper, we propose an approach for achieving detection and identification of faults, and provide fault tolerant control for systems that are modeled using timed hybrid Petri nets. For this purpose, an observer based technique is adopted which is useful in detection of faults, such as sensor faults, actuator faults, signal conditioning faults, etc. The concepts of estimation, reachability and diagnosability have been considered for analyzing faulty behaviors, and based on the detected faults, different schemes are proposed for achieving fault tolerant control using optimization techniques. These concepts are applied to a typical three tank system and numerical results are obtained.

  1. Suppressing decoherence and improving entanglement by quantum-jump-based feedback control in two-level systems

    SciTech Connect

    Hou, S. C.; Huang, X. L.; Yi, X. X.

    2010-07-15

    We study the quantum-jump-based feedback control on the entanglement shared between two qubits with one of them subject to decoherence while the other qubit is under the control. This situation is very relevant to a quantum system consisting of nuclear and electron spins in solid states. The possibility of prolonging the coherence time of the dissipative qubit is also explored. Numerical simulations show that the quantum-jump-based feedback control can improve the entanglement between the qubits and prolong the coherence time for the qubit subject directly to decoherence.

  2. IMC based feedforward controller framework for disturbance attenuation on uncertain systems.

    PubMed

    Vilanova, R; Arrieta, O; Ponsa, P

    2009-10-01

    This paper presents a generalization of the Internal Model Control (IMC) approach to feedforward control action generation. As is well known, one of the distinctive features of the IMC formulation is the possibility to distinguish between the nominal and uncertain situations. However the consideration of the presence of uncertainty for the feedforward part of the controller is not as simple as that for the feedback one. In this sense, what is proposed in this paper provides a more systematic way of addressing a robust feedforward design. In addition, being one of the major drawbacks of the Internal Model Control to have to deal with stable systems, the generalization presented here allows for unstable plants as well as unstable disturbance models.

  3. Construction of a controlled-release delivery system for pesticides using biodegradable PLA-based microcapsules.

    PubMed

    Liu, Baoxia; Wang, Yan; Yang, Fei; Wang, Xing; Shen, Hong; Cui, Haixin; Wu, Decheng

    2016-08-01

    Conventional pesticides usually need to be used in more than recommended dosages due to their loss and degradation, which results in a large waste of resources and serious environmental pollution. Encapsulation of pesticides in biodegradable carriers is a feasible approach to develop environment-friendly and efficient controlled-release delivery system. In this work, we fabricated three kinds of polylactic acid (PLA) carriers including microspheres, microcapsules, and porous microcapsules for controlled delivery of Lambda-Cyhalothrin (LC) via premix membrane emulsification (PME). The microcapsule delivery system had better water dispersion than the other two systems. Various microcapsules with a high LC contents as much as 40% and tunable sizes from 0.68 to 4.6μm were constructed by manipulating the process parameters. Compared with LC technical and commercial microcapsule formulation, the microcapsule systems showed a significantly sustained release of LC for a longer period. The LC release triggered by LC diffusion and matrix degradation could be optimally regulated by tuning LC contents and particle sizes of the microcapsules. This multi-regulated release capability is of great significance to achieve the precisely controlled release of pesticides. A preliminary bioassay against plutella xylostella revealed that 0.68μm LC-loaded microcapsules with good UV and thermal stability exhibited an activity similar to a commercial microcapsule formulation. These results demonstrated such an aqueous microcapsule delivery system had a great potential to be further explored for developing an effective and environmentally friendly pesticide-release formulation. PMID:27062215

  4. Centralized Monitoring of the Microsoft Windows-based computers of the LHC Experiment Control Systems

    NASA Astrophysics Data System (ADS)

    Varela Rodriguez, F.

    2011-12-01

    The control system of each of the four major Experiments at the CERN Large Hadron Collider (LHC) is distributed over up to 160 computers running either Linux or Microsoft Windows. A quick response to abnormal situations of the computer infrastructure is crucial to maximize the physics usage. For this reason, a tool was developed to supervise, identify errors and troubleshoot such a large system. Although the monitoring of the performance of the Linux computers and their processes was available since the first versions of the tool, it is only recently that the software package has been extended to provide similar functionality for the nodes running Microsoft Windows as this platform is the most commonly used in the LHC detector control systems. In this paper, the architecture and the functionality of the Windows Management Instrumentation (WMI) client developed to provide centralized monitoring of the nodes running different flavour of the Microsoft platform, as well as the interface to the SCADA software of the control systems are presented. The tool is currently being commissioned by the Experiments and it has already proven to be very efficient optimize the running systems and to detect misbehaving processes or nodes.

  5. Construction of a controlled-release delivery system for pesticides using biodegradable PLA-based microcapsules.

    PubMed

    Liu, Baoxia; Wang, Yan; Yang, Fei; Wang, Xing; Shen, Hong; Cui, Haixin; Wu, Decheng

    2016-08-01

    Conventional pesticides usually need to be used in more than recommended dosages due to their loss and degradation, which results in a large waste of resources and serious environmental pollution. Encapsulation of pesticides in biodegradable carriers is a feasible approach to develop environment-friendly and efficient controlled-release delivery system. In this work, we fabricated three kinds of polylactic acid (PLA) carriers including microspheres, microcapsules, and porous microcapsules for controlled delivery of Lambda-Cyhalothrin (LC) via premix membrane emulsification (PME). The microcapsule delivery system had better water dispersion than the other two systems. Various microcapsules with a high LC contents as much as 40% and tunable sizes from 0.68 to 4.6μm were constructed by manipulating the process parameters. Compared with LC technical and commercial microcapsule formulation, the microcapsule systems showed a significantly sustained release of LC for a longer period. The LC release triggered by LC diffusion and matrix degradation could be optimally regulated by tuning LC contents and particle sizes of the microcapsules. This multi-regulated release capability is of great significance to achieve the precisely controlled release of pesticides. A preliminary bioassay against plutella xylostella revealed that 0.68μm LC-loaded microcapsules with good UV and thermal stability exhibited an activity similar to a commercial microcapsule formulation. These results demonstrated such an aqueous microcapsule delivery system had a great potential to be further explored for developing an effective and environmentally friendly pesticide-release formulation.

  6. A new postural balance control system for rehabilitation training based on virtual cycling.

    PubMed

    Song, Chul Gyu; Kim, Jong Yun; Kim, Nam Gyun

    2004-06-01

    A new rehabilitation training system was developed to improve postural balance control by combining virtual reality technology with an unfixed bicycle. Twenty healthy subjects participated in the present study by riding the virtual cycling system under two different conditions: with or without visual feedback. Data were collected on the following parameters: path deviation, cycling velocity, etc. As a result of conducting the repeated training, results showed improvement not only in the ability to control balance and weight shift but also in the overall cycling ability including the degree of path deviation and the cycling speed. It was concluded that the system was effective as a training device and, in addition, the technology might have a wider applicability to the rehabilitation field.

  7. Switching sliding mode force tracking control of piezoelectric-hydraulic pump-based friction element actuation systems for automotive transmissions

    NASA Astrophysics Data System (ADS)

    Kim, Gi-Woo; Wang, K. W.

    2009-08-01

    In this study, a nonlinear sliding-mode controller is designed for force tracking of a piezoelectric-hydraulic pump (PHP)-based actuation system, which is developed to replace the current electro-hydraulic actuation systems for automatic transmission (AT) friction elements, such as band brakes or clutches. By utilizing the PHP, one can eliminate the various hydraulic components (oil pump, regulating valve and control valve) in current ATs and achieve a simpler configuration with more efficient operation. With the derived governing equation of motion of the PHP-based actuation system integrated with the friction element (band brake), a switching control law is synthesized based on the sliding-mode theory. To evaluate the effectiveness of the proposed control law, its force tracking performance for the engagement of a friction element during an AT 1\\to 2 up-shift is examined experimentally. It is shown that one can successfully track the desired force trajectory for AT shift control with small tracking error. This study demonstrates the potential of the PHP as a new controllable actuation system for AT friction elements.

  8. Nuclear materials control technology in the post-cold war world: Radiation-based methods and information management systems

    SciTech Connect

    Tape, J.W.; Eccleston, G.W.; Ensslin, N.; Markin, J.T.

    1993-06-01

    The end of the cold war is providing both opportunities and requirements for improving the control of nuclear materials around the world. The dismantlement of nuclear weapons and the growth of nuclear power, including the use of plutonium in light water reactors and breeder reactor programs, coupled with enhanced proliferation concerns, drive the need for improved nuclear materials control. We describe nuclear materials control and the role of technology in making controls more effective and efficient. The current use and anticipated development in selected radiation-based methods and related information management systems am described briefly.

  9. SPring-8 beamline control system.

    PubMed

    Ohata, T; Konishi, H; Kimura, H; Furukawa, Y; Tamasaku, K; Nakatani, T; Tanabe, T; Matsumoto, N; Ishii, M; Ishikawa, T

    1998-05-01

    The SPring-8 beamline control system is now taking part in the control of the insertion device (ID), front end, beam transportation channel and all interlock systems of the beamline: it will supply a highly standardized environment of apparatus control for collaborative researchers. In particular, ID operation is very important in a third-generation synchrotron light source facility. It is also very important to consider the security system because the ID is part of the storage ring and is therefore governed by the synchrotron ring control system. The progress of computer networking systems and the technology of security control require the development of a highly flexible control system. An interlock system that is independent of the control system has increased the reliability. For the beamline control system the so-called standard model concept has been adopted. VME-bus (VME) is used as the front-end control system and a UNIX workstation as the operator console. CPU boards of the VME-bus are RISC processor-based board computers operated by a LynxOS-based HP-RT real-time operating system. The workstation and the VME are linked to each other by a network, and form the distributed system. The HP 9000/700 series with HP-UX and the HP 9000/743rt series with HP-RT are used. All the controllable apparatus may be operated from any workstation. PMID:15263588

  10. A Prototype Lisp-Based Soft Real-Time Object-Oriented Graphical User Interface for Control System Development

    NASA Technical Reports Server (NTRS)

    Litt, Jonathan; Wong, Edmond; Simon, Donald L.

    1994-01-01

    A prototype Lisp-based soft real-time object-oriented Graphical User Interface for control system development is presented. The Graphical User Interface executes alongside a test system in laboratory conditions to permit observation of the closed loop operation through animation, graphics, and text. Since it must perform interactive graphics while updating the screen in real time, techniques are discussed which allow quick, efficient data processing and animation. Examples from an implementation are included to demonstrate some typical functionalities which allow the user to follow the control system's operation.

  11. Non-linear system control using a recurrent fuzzy neural network based on improved particle swarm optimisation

    NASA Astrophysics Data System (ADS)

    Lin, Cheng-Jian; Lee, Chi-Yung

    2010-04-01

    This article introduces a recurrent fuzzy neural network based on improved particle swarm optimisation (IPSO) for non-linear system control. An IPSO method which consists of the modified evolutionary direction operator (MEDO) and the Particle Swarm Optimisation (PSO) is proposed in this article. A MEDO combining the evolutionary direction operator and the migration operation is also proposed. The MEDO will improve the global search solution. Experimental results have shown that the proposed IPSO method controls the magnetic levitation system and the planetary train type inverted pendulum system better than the traditional PSO and the genetic algorithm methods.

  12. A feasibility study on image-based control of surgical robot using a 60-GHz wireless communication system.

    PubMed

    Takizawa, Kenichi; Omori, Shigeru; Harada, Hideo; Nakamura, Ryoichi; Muragaki, Yoshihiro; Iseki, Hiroshi

    2009-01-01

    This paper presents an evaluation study on the feasibility of introducing wireless connection into a neurosurgical robot, which is controlled by an image-based navigation system. The wireless connection introduced into the robotic system is based on amplitude shift keying (ASK) at 60 GHz. With this wireless connection, data transmission at the bit-rate of 1 Gbps or more is possible, and here high-definition video images (1080i/1080p) can be transmitted. Such a wireless connection system is implemented in the surgical robot replaces the cable connection between the digital video camera and the controller. In this study, the wireless robotic surgical system is evaluated in terms of its accuracy of navigation using the transmitted video images. The results of a wireless connection test under a line-of-sight (LOS) environment show that navigation accuracy observed when using this wireless surgical robot is comparable to that when using a wired robotic system. PMID:19963666

  13. Adaptive GSA-based optimal tuning of PI controlled servo systems with reduced process parametric sensitivity, robust stability and controller robustness.

    PubMed

    Precup, Radu-Emil; David, Radu-Codrut; Petriu, Emil M; Radac, Mircea-Bogdan; Preitl, Stefan

    2014-11-01

    This paper suggests a new generation of optimal PI controllers for a class of servo systems characterized by saturation and dead zone static nonlinearities and second-order models with an integral component. The objective functions are expressed as the integral of time multiplied by absolute error plus the weighted sum of the integrals of output sensitivity functions of the state sensitivity models with respect to two process parametric variations. The PI controller tuning conditions applied to a simplified linear process model involve a single design parameter specific to the extended symmetrical optimum (ESO) method which offers the desired tradeoff to several control system performance indices. An original back-calculation and tracking anti-windup scheme is proposed in order to prevent the integrator wind-up and to compensate for the dead zone nonlinearity of the process. The minimization of the objective functions is carried out in the framework of optimization problems with inequality constraints which guarantee the robust stability with respect to the process parametric variations and the controller robustness. An adaptive gravitational search algorithm (GSA) solves the optimization problems focused on the optimal tuning of the design parameter specific to the ESO method and of the anti-windup tracking gain. A tuning method for PI controllers is proposed as an efficient approach to the design of resilient control systems. The tuning method and the PI controllers are experimentally validated by the adaptive GSA-based tuning of PI controllers for the angular position control of a laboratory servo system. PMID:25330468

  14. Remote Manipulator System (RMS)-based Controls-Structures Interaction (CSI) flight experiment feasibility study

    NASA Technical Reports Server (NTRS)

    Demeo, Martha E.

    1990-01-01

    The feasibility of an experiment which will provide an on-orbit validation of Controls-Structures Interaction (CSI) technology, was investigated. The experiment will demonstrate the on-orbit characterization and flexible-body control of large flexible structure dynamics using the shuttle Remote Manipulator System (RMS) with an attached payload as a test article. By utilizing existing hardware as well as establishing integration, operation and safety algorithms, techniques and procedures, the experiment will minimize the costs and risks of implementing a flight experiment. The experiment will also offer spin-off enhancement to both the Shuttle RMS (SRMS) and the Space Station RMS (SSRMS).

  15. An Easy to Deploy Street Light Control System Based on Wireless Communication and LED Technology

    PubMed Central

    Elejoste, Pilar; Angulo, Ignacio; Perallos, Asier; Chertudi, Aitor; Zuazola, Ignacio Julio García; Moreno, Asier; Azpilicueta, Leire; Astrain, José Javier; Falcone, Francisco; Villadangos, Jesús

    2013-01-01

    This paper presents an intelligent streetlight management system based on LED lamps, designed to facilitate its deployment in existing facilities. The proposed approach, which is based on wireless communication technologies, will minimize the cost of investment of traditional wired systems, which always need civil engineering for burying of cable underground and consequently are more expensive than if the connection of the different nodes is made over the air. The deployed solution will be aware of their surrounding's environmental conditions, a fact that will be approached for the system intelligence in order to learn, and later, apply dynamic rules. The knowledge of real time illumination needs, in terms of instant use of the street in which it is installed, will also feed our system, with the objective of providing tangible solutions to reduce energy consumption according to the contextual needs, an exact calculation of energy consumption and reliable mechanisms for preventive maintenance of facilities. PMID:23681092

  16. Implementation of RS-485 Communication between PLC and PC of Distributed Control System Based on VB

    NASA Astrophysics Data System (ADS)

    Lian Zhang, Chuan; Da Huang, Zhi; Qing Zhou, Gui; Chong, Kil To

    2015-05-01

    This paper focuses on achieving RS-485 communication between programmable logical controller (PLC) and PC based on visual basic 6.0 (VB6.0) on an experimental automatic production line. Mitsubishi FX2N PLCs and a PC are chosen as slave stations and main station, respectively. Monitoring software is developed using VB6.0 for data input/output, flow control and online parameters setting. As a result, all functions are fulfilled with robust performance. It is concluded from results that one PC can monitor several PLCs using RS-485 communication.

  17. Comprehensive Evaluation of Biological Growth Control by Chlorine-Based Biocides in Power Plant Cooling Systems Using Tertiary Effluent.

    PubMed

    Chien, Shih-Hsiang; Dzombak, David A; Vidic, Radisav D

    2013-06-01

    Recent studies have shown that treated municipal wastewater can be a reliable cooling water alternative to fresh water. However, elevated nutrient concentration and microbial population in wastewater lead to aggressive biological proliferation in the cooling system. Three chlorine-based biocides were evaluated for the control of biological growth in cooling systems using tertiary treated wastewater as makeup, based on their biocidal efficiency and cost-effectiveness. Optimal chemical regimens for achieving successful biological growth control were elucidated based on batch-, bench-, and pilot-scale experiments. Biocide usage and biological activity in planktonic and sessile phases were carefully monitored to understand biological growth potential and biocidal efficiency of the three disinfectants in this particular environment. Water parameters, such as temperature, cycles of concentration, and ammonia concentration in recirculating water, critically affected the biocide performance in recirculating cooling systems. Bench-scale recirculating tests were shown to adequately predict the biocide residual required for a pilot-scale cooling system. Optimal residuals needed for proper biological growth control were 1, 2-3, and 0.5-1 mg/L as Cl2 for NaOCl, preformed NH2Cl, and ClO2, respectively. Pilot-scale tests also revealed that Legionella pneumophila was absent from these cooling systems when using the disinfectants evaluated in this study. Cost analysis showed that NaOCl is the most cost-effective for controlling biological growth in power plant recirculating cooling systems using tertiary-treated wastewater as makeup. PMID:23781129

  18. Automation infrastructure and operation control strategy in a stand-alone power system based on renewable energy sources

    NASA Astrophysics Data System (ADS)

    Ziogou, Chrysovalantou; Ipsakis, Dimitris; Elmasides, Costas; Stergiopoulos, Fotis; Papadopoulou, Simira; Seferlis, Panos; Voutetakis, Spyros

    The design of the automation system and the implemented operation control strategy in a stand-alone power system in Greece are fully analyzed in the present study. A photovoltaic array and three wind generators serve as the system main power sources and meet a predefined load demand. A lead-acid accumulator is used to compensate the inherent power fluctuations (excess or shortage) and to regulate the overall system operation, based on a developed power management strategy. Hydrogen is produced by using system excess power in a proton exchange membrane (PEM) electrolyzer and is further stored in pressurized cylinders for subsequent use in a PEM fuel cell in cases of power shortage. A diesel generator complements the integrated system and is employed only in emergency cases, such as subsystems failure. The performance of the automatic control system is evaluated through the real-time operation of the power system where data from the various subsystems are recorded and analyzed using a supervised data acquisition unit. Various network protocols were used to integrate the system devices into one central control system managing in this way to compensate for the differences between chemical and electrical subunits. One of the main advantages is the ability of process monitoring from distance where users can perform changes to system principal variables. Furthermore, the performance of the implemented power management strategy is evaluated through simulated scenarios by including a case study analysis on system abilities to meet higher than expected electrical load demands.

  19. An adaptive neuro fuzzy inference system controlled space cector pulse width modulation based HVDC light transmission system under AC fault conditions

    NASA Astrophysics Data System (ADS)

    Ajay Kumar, M.; Srikanth, N. V.

    2014-03-01

    In HVDC Light transmission systems, converter control is one of the major fields of present day research works. In this paper, fuzzy logic controller is utilized for controlling both the converters of the space vector pulse width modulation (SVPWM) based HVDC Light transmission systems. Due to its complexity in the rule base formation, an intelligent controller known as adaptive neuro fuzzy inference system (ANFIS) controller is also introduced in this paper. The proposed ANFIS controller changes the PI gains automatically for different operating conditions. A hybrid learning method which combines and exploits the best features of both the back propagation algorithm and least square estimation method is used to train the 5-layer ANFIS controller. The performance of the proposed ANFIS controller is compared and validated with the fuzzy logic controller and also with the fixed gain conventional PI controller. The simulations are carried out in the MATLAB/SIMULINK environment. The results reveal that the proposed ANFIS controller is reducing power fluctuations at both the converters. It also improves the dynamic performance of the test power system effectively when tested for various ac fault conditions.

  20. Airflow control system

    DOEpatents

    Motszko, Sean Ronald; McEnaney, Ryan Patrick; Brush, Jeffrey Alan; Zimmermann, Daniel E.

    2007-03-13

    A dual airflow control system for an environment having a first air zone and a second air zone. The system includes a first input device operable to generate a first input signal indicative of a desired airflow to the first zone and a second input device operable to generate a second input signal indicative of a desired airflow to the second zone. First and second flow regulators are configured to regulate airflow to the first and second zones, respectively, such that the first and second regulators selectively provide the airflow to each of the first and second zones based on the first and second input signals. A single actuator is associated with the first and second flow regulators. The actuator is operable to simultaneously actuate the first and second flow regulators based on an input from the first and second input devices to allow the desired airflows to the first and the second zones.