Attitude tracking control of flexible spacecraft with large amplitude slosh

NASA Astrophysics Data System (ADS)

Deng, Mingle; Yue, Baozeng

2017-12-01

This paper is focused on attitude tracking control of a spacecraft that is equipped with flexible appendage and partially filled liquid propellant tank. The large amplitude liquid slosh is included by using a moving pulsating ball model that is further improved to estimate the settling location of liquid in microgravity or a zero-g environment. The flexible appendage is modelled as a three-dimensional Bernoulli-Euler beam, and the assumed modal method is employed. A hybrid controller that combines sliding mode control with an adaptive algorithm is designed for spacecraft to perform attitude tracking. The proposed controller has proved to be asymptotically stable. A nonlinear model for the overall coupled system including spacecraft attitude dynamics, liquid slosh, structural vibration and control action is established. Numerical simulation results are presented to show the dynamic behaviors of the coupled system and to verify the effectiveness of the control approach when the spacecraft undergoes the disturbance produced by large amplitude slosh and appendage vibration. Lastly, the designed adaptive algorithm is found to be effective to improve the precision of attitude tracking.

Conical-scan tracking with the 64-m-diameter antenna at goldstone

NASA Technical Reports Server (NTRS)

Ohlson, J. E.; Reid, M. S.

1976-01-01

The theory and experimental work which demonstrated the feasibility of conical-scan tracking with a 64 m diameter paraboloid antenna is documented. The purpose of this scheme is to actively track spacecraft and radio sources continuously with an accuracy superior to that obtained by manual correction of the computer driven pointing. The conical-scan implementation gives increased tracking accuracy with X-band spacecraft signals, as demonstrated in the Mariner Venus/Mercury 1973 mission. Also, the high accuracy and ease of measurement with conical-scan tracking allow evaluation of systematic and random antenna tracking errors.

Pseudorandom Switching for Adding Radar to the AFF Sensor

NASA Technical Reports Server (NTRS)

Tien, Jeffrey; Purcell, George; Young, Lawrence

2006-01-01

A document describes the proposed addition of a radar function to the Autonomous Formation Flying Sensor, making possible coarse relative-position control to prevent collisions in the event of failure of one of the spacecraft. According to the proposal, in addition to tracking GPS-like one-way ranging signals transmitted by the other normally functioning spacecraft, each spacecraft could simultaneously track the reflection of its own ranging signal from a disabled, non-transmitting spacecraft. From the round-trip travel time, the approximate distance to the disabled spacecraft could be estimated. To prevent jamming of the receiver by the transmitter on the same spacecraft, the receiver would be switched off during transmission.

Adaptive quaternion tracking with nonlinear extended state observer

NASA Astrophysics Data System (ADS)

Bai, Yu-liang; Wang, Xiao-gang; Xu, Jiang-tao; Cui, Nai-gang

2017-10-01

This paper addresses the problem of attitude tracking for spacecraft in the presence of uncertainties in moments of inertia and environmental disturbances. An adaptive quaternion tracking control is combined with a nonlinear extended state observer and the disturbances compensated for in each sampling period. The tracking controller is proved to asymptotically track a prescribed motion in the presence of these uncertainties. Simulations of a nano-spacecraft demonstrate a significant improvement in pointing accuracy and tracking error when compared to a conventional attitude controller. The proposed tracking control is completely deterministic, simple to implement, does not require knowledge of the uncertainties and does not suffer from chattering.

Relative position finite-time coordinated tracking control of spacecraft formation without velocity measurements.

PubMed

Hu, Qinglei; Zhang, Jian

2015-01-01

This paper investigates finite-time relative position coordinated tracking problem by output feedback for spacecraft formation flying without velocity measurement. By employing homogeneous system theory, a finite-time relative position coordinated tracking controller by state feedback is firstly developed, where the desired time-varying trajectory given in advance can be tracked by the formation. Then, to address the problem of lack of velocity measurements, a finite-time output feedback controller is proposed by involving a novel filter to recover unknown velocity information in a finite time. Rigorous proof shows that the proposed control law ensures global stability and guarantees the position of spacecraft formation to track a time-varying reference in finite time. Finally, simulation results are presented to illustrate the performance of the proposed controller. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

Lunar Orbiter II - Photographic Mission Summary

NASA Technical Reports Server (NTRS)

1967-01-01

Lunar Orbiter II photography of landing sites, and spacecraft systems performance. The second of five Lunar Orbiter spacecraft was successfully launched from Launch Complex 13 at the Air Force Eastern Test Range by an Atlas-Agena launch vehicle at 23:21 GMT on November 6, 1966. Tracking data from the Cape Kennedy and Grand Bahama tracking stations were used to control and guide the launch vehicle during Atlas powered flight. The Agena spacecraft combination was maneuvered into a 100-nautical-mile-altitude Earth orbit by the preset on-board Agena computer. In addition, the Agena computer determined the maneuver 1 and engine-bum period required to inject the spacecraft on the cislunar trajectory 20 minutes after launch. Tracking data from the downrange stations and the Johannesburg, South Africa station were used to monitor the entire boost trajectory.

Antenna Controller Replacement Software

NASA Technical Reports Server (NTRS)

Chao, Roger Y.; Morgan, Scott C.; Strain, Martha M.; Rockwell, Stephen T.; Shimizu, Kenneth J.; Tehrani, Barzia J.; Kwok, Jaclyn H.; Tuazon-Wong, Michelle; Valtier, Henry; Nalbandi, Reza;

Space tracking and data systems; Proceedings of the Symposium, Arlington, VA, June 16-18, 1981

NASA Technical Reports Server (NTRS)

Grey, J. (Editor); Hamdan, L. A.

1981-01-01

The AIAA/NASA Symposium on Space Tracking and Data Systems, held in Pentagon City, Virginia, on June 16-18, 1981, had the purpose of reviewing international activities in space tracking and data systems for civil use in the 1980-2000 time frame. Participants included 225 representatives from industrial and government organizations in eight nations. The nations represented include the United States, France, Germany, India, Japan, Norway, Spain, and Sweden. The major functions of the systems described at the Symposium are related to the initial downlink of telemetry and spacecraft status data, attendant tracking activities, and uplink of spacecraft commands; communication between the associated acquisition sites and central processing and control stations; formulation and implementation of commands that control the spacecraft and its payload; and processing of spacecraft data needed to make command decisions. Attention is given to an overview of current activities and plans, and supporting developments, taking into account the time from 1980 to 1990. New developments are also considered.

Adaptive Jacobian Fuzzy Attitude Control for Flexible Spacecraft Combined Attitude and Sun Tracking System

NASA Astrophysics Data System (ADS)

Chak, Yew-Chung; Varatharajoo, Renuganth

2016-07-01

Many spacecraft attitude control systems today use reaction wheels to deliver precise torques to achieve three-axis attitude stabilization. However, irrecoverable mechanical failure of reaction wheels could potentially lead to mission interruption or total loss. The electrically-powered Solar Array Drive Assemblies (SADA) are usually installed in the pitch axis which rotate the solar arrays to track the Sun, can produce torques to compensate for the pitch-axis wheel failure. In addition, the attitude control of a flexible spacecraft poses a difficult problem. These difficulties include the strong nonlinear coupled dynamics between the rigid hub and flexible solar arrays, and the imprecisely known system parameters, such as inertia matrix, damping ratios, and flexible mode frequencies. In order to overcome these drawbacks, the adaptive Jacobian tracking fuzzy control is proposed for the combined attitude and sun-tracking control problem of a flexible spacecraft during attitude maneuvers in this work. For the adaptation of kinematic and dynamic uncertainties, the proposed scheme uses an adaptive sliding vector based on estimated attitude velocity via approximate Jacobian matrix. The unknown nonlinearities are approximated by deriving the fuzzy models with a set of linguistic If-Then rules using the idea of sector nonlinearity and local approximation in fuzzy partition spaces. The uncertain parameters of the estimated nonlinearities and the Jacobian matrix are being adjusted online by an adaptive law to realize feedback control. The attitude of the spacecraft can be directly controlled with the Jacobian feedback control when the attitude pointing trajectory is designed with respect to the spacecraft coordinate frame itself. A significant feature of this work is that the proposed adaptive Jacobian tracking scheme will result in not only the convergence of angular position and angular velocity tracking errors, but also the convergence of estimated angular velocity to the actual angular velocity. Numerical results are presented to demonstrate the effectiveness of the proposed scheme in tracking the desired attitude, as well as suppressing the elastic deflection effects of solar arrays during maneuver.

Tracking Data Certification for the Lunar Reconnaissance Orbiter

NASA Technical Reports Server (NTRS)

Morinelli, Patrick J.; Socoby, Joseph; Hendry, Steve; Campion, Richard

2010-01-01

This paper details the National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC) Flight Dynamics Facility (FDF) tracking data certification effort of the Lunar Reconnaissance Orbiter (LRO) Space Communications Network (SCN) complement of tracking stations consisting of the NASA White Sands 1 antenna (WS1), and the commercial provider Universal Space Network (USN) antennas at South Point, Hawaii; Dongara Australia; Weilheim, Germany; and Kiruna, Sweden. Certification assessment required the cooperation and coordination of parties not under the control of either the LRO project or ground stations as uplinks on cooperating spacecraft were necessary. The LRO range-tracking requirement of 10m 1 sigma could be satisfactorily demonstrated using any typical spacecraft capable of range tracking. Though typical Low Earth Orbiting (LEO) or Geosynchronous Earth Orbiting (GEO) spacecraft may be adequate for range certification, their measurement dynamics and noise would be unacceptable for proper Doppler certification of 1-3mm/sec 1 sigma. As LRO will orbit the Moon, it was imperative that a suitable target spacecraft be utilized which can closely mimic the expected lunar orbital Doppler dynamics of +/-1.6km/sec and +/-1.5m/sq sec to +/-0.15m/sq sec, is in view of the ground stations, supports coherent S-Band Doppler tracking measurements, and can be modeled by the FDF. In order to meet the LRO metric tracking data specifications, the SCN ground stations employed previously uncertified numerically controlled tracking receivers. Initial certification testing revealed certain characteristics of the units that required resolution before being granted certification.

Sub-nanosecond clock synchronization and precision deep space tracking

NASA Technical Reports Server (NTRS)

Dunn, Charles; Lichten, Stephen; Jefferson, David; Border, James S.

1992-01-01

Interferometric spacecraft tracking is accomplished at the NASA Deep Space Network (DSN) by comparing the arrival time of electromagnetic spacecraft signals to ground antennas separated by baselines on the order of 8000 km. Clock synchronization errors within and between DSN stations directly impact the attainable tracking accuracy, with a 0.3 ns error in clock synchronization resulting in an 11 nrad angular position error. This level of synchronization is currently achieved by observing a quasar which is angularly close to the spacecraft just after the spacecraft observations. By determining the differential arrival times of the random quasar signal at the stations, clock synchronization and propagation delays within the atmosphere and within the DSN stations are calibrated. Recent developments in time transfer techniques may allow medium accuracy (50-100 nrad) spacecraft observations without near-simultaneous quasar-based calibrations. Solutions are presented for a global network of GPS receivers in which the formal errors in clock offset parameters are less than 0.5 ns. Comparisons of clock rate offsets derived from GPS measurements and from very long baseline interferometry and the examination of clock closure suggest that these formal errors are a realistic measure of GPS-based clock offset precision and accuracy. Incorporating GPS-based clock synchronization measurements into a spacecraft differential ranging system would allow tracking without near-simultaneous quasar observations. The impact on individual spacecraft navigation error sources due to elimination of quasar-based calibrations is presented. System implementation, including calibration of station electronic delays, is discussed.

Planetary Radio Interferometry and Doppler Experiment (PRIDE) technique: A test case of the Mars Express Phobos Flyby. II. Doppler tracking: Formulation of observed and computed values, and noise budget

NASA Astrophysics Data System (ADS)

Bocanegra-Bahamón, T. M.; Molera Calvés, G.; Gurvits, L. I.; Duev, D. A.; Pogrebenko, S. V.; Cimò, G.; Dirkx, D.; Rosenblatt, P.

2018-01-01

Context. Closed-loop Doppler data obtained by deep space tracking networks, such as the NASA Deep Space Network (DSN) and the ESA tracking station network (Estrack), are routinely used for navigation and science applications. By shadow tracking the spacecraft signal, Earth-based radio telescopes involved in the Planetary Radio Interferometry and Doppler Experiment (PRIDE) can provide open-loop Doppler tracking data only when the dedicated deep space tracking facilities are operating in closed-loop mode. Aims: We explain the data processing pipeline in detail and discuss the capabilities of the technique and its potential applications in planetary science. Methods: We provide the formulation of the observed and computed values of the Doppler data in PRIDE tracking of spacecraft and demonstrate the quality of the results using an experiment with the ESA Mars Express spacecraft as a test case. Results: We find that the Doppler residuals and the corresponding noise budget of the open-loop Doppler detections obtained with the PRIDE stations compare to the closed-loop Doppler detections obtained with dedicated deep space tracking facilities.

Differential tracking data types for accurate and efficient Mars planetary navigation

NASA Technical Reports Server (NTRS)

Edwards, C. D., Jr.; Kahn, R. D.; Folkner, W. M.; Border, J. S.

1991-01-01

Ways in which high-accuracy differential observations of two or more deep space vehicles can dramatically extend the power of earth-based tracking over conventional range and Doppler tracking are discussed. Two techniques - spacecraft-spacecraft differential very long baseline interferometry (S/C-S/C Delta(VLBI)) and same-beam interferometry (SBI) - are discussed. The tracking and navigation capabilities of conventional range, Doppler, and quasar-relative Delta(VLBI) are reviewed, and the S/C-S/C Delta (VLBI) and SBI types are introduced. For each data type, the formation of the observable is discussed, an error budget describing how physical error sources manifest themselves in the observable is presented, and potential applications of the technique for Space Exploration Initiative scenarios are examined. Requirements for spacecraft and ground systems needed to enable and optimize these types of observations are discussed.

Frequency standards requirements of the NASA deep space network to support outer planet missions

NASA Technical Reports Server (NTRS)

Fliegel, H. F.; Chao, C. C.

1974-01-01

Navigation of Mariner spacecraft to Jupiter and beyond will require greater accuracy of positional determination than heretofore obtained if the full experimental capabilities of this type of spacecraft are to be utilized. Advanced navigational techniques which will be available by 1977 include Very Long Baseline Interferometry (VLBI), three-way Doppler tracking (sometimes called quasi-VLBI), and two-way Doppler tracking. It is shown that VLBI and quasi-VLBI methods depend on the same basic concept, and that they impose nearly the same requirements on the stability of frequency standards at the tracking stations. It is also shown how a realistic modelling of spacecraft navigational errors prevents overspecifying the requirements to frequency stability.

KSC-2009-5012

NASA Image and Video Library

2009-08-03

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., the SV1 and SV2 spacecraft are ready for mating for launch. The two spacecraft are part of the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, Program. STSS-Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. The spacecraft is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

An Overview of the Orbital Debris and Meteoroid Environments, Their Effects on Spacecraft, and What Can We Do About It?

NASA Technical Reports Server (NTRS)

Matney, Mark

2017-01-01

Because of the high speeds needed for orbital space flight, hypervelocity impacts with objects in space are a constant risk to spacecraft. This includes natural debris - meteoroids - and the debris remnants of our own activities in space. A number of space surveillance assets are used to measure and track spacecraft, used upper stages, and breakup debris. However, much of the debris and meteoroids encountered by spacecraft in Earth orbit is not easily measured or tracked. For every man-made object that we can track, there are hundreds of small debris that are too small to be tracked but still large enough to damage spacecraft. In addition, even if we knew today's environment with perfect knowledge, the debris environment is dynamic and would change tomorrow. This means that much of the risk from both meteoroids and anthropogenic debris is statistical in nature. NASA uses and maintains a number of instruments to statistically monitor the meteoroid and orbital debris environments, and uses this information to compute statistical models for use by spacecraft designers and operators. Because orbital debris is a result of human activities, NASA has led the US government in formulating national and international strategies that space users can employ to limit the growth of debris in the future. This talk will summarize the history and current state of meteoroid and space debris measurements and modeling, how the environment influences spacecraft design and operations, how we are designing the experiments of tomorrow to improve our knowledge, and how we are working internationally to preserve the space environment for the future.

The spacecraft control laboratory experiment optical attitude measurement system

NASA Technical Reports Server (NTRS)

Welch, Sharon S.; Montgomery, Raymond C.; Barsky, Michael F.

1991-01-01

A stereo camera tracking system was developed to provide a near real-time measure of the position and attitude of the Spacecraft COntrol Laboratory Experiment (SCOLE). The SCOLE is a mockup of the shuttle-like vehicle with an attached flexible mast and (simulated) antenna, and was designed to provide a laboratory environment for the verification and testing of control laws for large flexible spacecraft. Actuators and sensors located on the shuttle and antenna sense the states of the spacecraft and allow the position and attitude to be controlled. The stereo camera tracking system which was developed consists of two position sensitive detector cameras which sense the locations of small infrared LEDs attached to the surface of the shuttle. Information on shuttle position and attitude is provided in six degrees-of-freedom. The design of this optical system, calibration, and tracking algorithm are described. The performance of the system is evaluated for yaw only.

Tracking and data relay satellite system configuration and tradeoff study. Volume 4: Spacecraft and subsystem design, part 1

NASA Technical Reports Server (NTRS)

Hill, T. E.

1972-01-01

The design and development of the Tracking and Data Relay satellite are discussed. The subjects covered are: (1) spacecraft mechanical and structural design, (2) attitude stabilization and control subsystem, (3) propulsion system, (4) electrical power subsystem, (5) thermal control, and (6) reliability engineering.

ADRC for spacecraft attitude and position synchronization in libration point orbits

NASA Astrophysics Data System (ADS)

Gao, Chen; Yuan, Jianping; Zhao, Yakun

2018-04-01

This paper addresses the problem of spacecraft attitude and position synchronization in libration point orbits between a leader and a follower. Using dual quaternion, the dimensionless relative coupled dynamical model is derived considering computation efficiency and accuracy. Then a model-independent dimensionless cascade pose-feedback active disturbance rejection controller is designed to spacecraft attitude and position tracking control problems considering parameter uncertainties and external disturbances. Numerical simulations for the final approach phase in spacecraft rendezvous and docking and formation flying are done, and the results show high-precision tracking errors and satisfactory convergent rates under bounded control torque and force which validate the proposed approach.

Robust inertia-free attitude takeover control of postcapture combined spacecraft with guaranteed prescribed performance.

PubMed

Luo, Jianjun; Wei, Caisheng; Dai, Honghua; Yin, Zeyang; Wei, Xing; Yuan, Jianping

2018-03-01

In this paper, a robust inertia-free attitude takeover control scheme with guaranteed prescribed performance is investigated for postcapture combined spacecraft with consideration of unmeasurable states, unknown inertial property and external disturbance torque. Firstly, to estimate the unavailable angular velocity of combination accurately, a novel finite-time-convergent tracking differentiator is developed with a quite computationally achievable structure free from the unknown nonlinear dynamics of combined spacecraft. Then, a robust inertia-free prescribed performance control scheme is proposed, wherein, the transient and steady-state performance of combined spacecraft is first quantitatively studied by stabilizing the filtered attitude tracking errors. Compared with the existing works, the prominent advantage is that no parameter identifications and no neural or fuzzy nonlinear approximations are needed, which decreases the complexity of robust controller design dramatically. Moreover, the prescribed performance of combined spacecraft is guaranteed a priori without resorting to repeated regulations of the controller parameters. Finally, four illustrative examples are employed to validate the effectiveness of the proposed control scheme and tracking differentiator. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

Spacecraft Doppler Tracking as a Xylophone Detector

NASA Technical Reports Server (NTRS)

Tinto, Massimo

1996-01-01

We discuss spacecraft Doppler tracking in which Doppler data recorded on the ground are linearly combined with Doppler measurements made on board a spacecraft. By using the four-link radio system first proposed by Vessot and Levine, we derive a new method for removing from the combined data the frequency fluctuations due to the Earth troposphere, ionosphere, and mechanical vibrations of the antenna on the ground. Our method provides also for reducing by several orders of magnitude, at selected Fourier components, the frequency fluctuations due to other noise sources, such as the clock on board the spacecraft or the antenna and buffeting of the probe by non-gravitational forces. In this respect spacecraft Doppler tracking can be regarded as a xylophone detector. Estimates of the sensitivities achievable by this xylophone are presented for two tests of Einstein's theory of relativity: searches for gravitational waves and measurements of the gravitational red shift. This experimental technique could be extended to other tests of the theory of relativity, and to radio science experiments that rely on high-precision Doppler measurements.

KSC-2009-5015

NASA Image and Video Library

2009-08-03

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., a crane moves the SV1 spacecraft, which will be mated with the SV2 at right. The two spacecraft are part of the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, Program. STSS-Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. The spacecraft is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

Tracking and data relay satellite system - NASA's new spacecraft data acquisition system

NASA Technical Reports Server (NTRS)

Schneider, W. C.; Garman, A. A.

1979-01-01

This paper describes NASA's new spacecraft acquisition system provided by the Tracking and Data Relay Satellite System (TDRSS). Four satellites in geostationary orbit and a ground terminal will provide complete tracking, telemetry, and command service for all of NASA's orbital satellites below a 12,000 km altitude. Western Union will lease the system, operate the ground terminal and provide operational satellite control. NASA's network control center will be the focal point for scheduling user services and controlling the interface between TDRSS and the NASA communications network, project control centers, and data processing. TDRSS single access user spacecraft data systems will be designed for time shared data relay support, and reimbursement policy and rate structure for non-NASA users are being developed.

The Cassini gravitational wave experiment

NASA Astrophysics Data System (ADS)

Abbate, Salvatore F.; Armstrong, John W.; Asmar, Sami W.; Barbinis, Elias; Bertotti, Bruno; Fleischman, Don U.; Gatti, Mark S.; Goltz, Gene L.; Herrera, R. G.; Iess, L.; Lee, Kyong J.; Ray, Trina L.; Tinto, Massimo; Tortora, P.; Wahlquist, Hugo D.

2003-03-01

Doppler tracking experiments using the earth and a distant spacecraft as separated test masses have been used for gravitational wave (GW) searches in the low-frequency band(~0.0001-0.1 Hz). The precision microwave tracking link continuously measures the relative dimensionless velocity, Δv/c, between the earth and the spacecraft. A GW incident of the systems produces a characteristic signature in the data, different from the signatures of the principal noises. For 40 days centered about its solar opposition in December 2001, the Cassini spacecraft was tracked in a search for low-frequncy GWs. Here we describe the GW experiment, including transfer functions of the signals and noises to the Doppler observable, and present noise statistics and compare them with the pre-experiment noise budget.

Energy management and attitude control for spacecraft

NASA Astrophysics Data System (ADS)

Costic, Bret Thomas

2001-07-01

This PhD dissertation describes the design and implementation of various control strategies centered around spacecraft applications: (i) an attitude control system for spacecraft, (ii) flywheels used for combined attitude and energy tracking, and (iii) an adaptive autobalancing control algorithm. The theory found in each of these sections is demonstrated through simulation or experimental results. An introduction to each of these three primary chapters can be found in chapter one. The main problem addressed in the second chapter is the quaternion-based, attitude tracking control of rigid spacecraft without angular velocity measurements and in the presence of an unknown inertia matrix. As a stepping-stone, an adaptive, full-state feedback controller that compensates for parametric uncertainty while ensuring asymptotic attitude tracking errors is designed. The adaptive, full-state feedback controller is then redesigned such that the need for angular velocity measurements is eliminated. The proposed adaptive, output feedback controller ensures asymptotic attitude tracking. This work uses a four-parameter representation of the spacecraft attitude that does not exhibit singular orientations as in the case of the previous three-parameter representation-based results. To the best of my knowledge, this represents the first solution to the adaptive, output feedback, attitude tracking control problem for the quaternion representation. Simulation results are included to illustrate the performance of the proposed output feedback control strategy. The third chapter is devoted to the use of multiple flywheels that integrate the energy storage and attitude control functions in space vehicles. This concept, which is referred to as an Integrated Energy Management and Attitude Control (IEMAC) system, reduces the space vehicle bus mass, volume, cost, and maintenance requirements while maintaining or improving the space vehicle performance. To this end, two nonlinear IEMAC strategies (model-based and adaptive) that simultaneously track a desired attitude trajectory and desired energy/power profile are presented. Both strategies ensure asymptotic tracking while the adaptive controller compensates for uncertain spacecraft inertia. In the final chapter, a control strategy is designed for a rotating, unbalanced disk. The control strategy, which is composed of a control torque and two control forces, regulates the disk displacement and ensures angular velocity tracking. The controller uses a desired compensation adaptation law and a gain adjusted forgetting factor to achieve exponential stability despite the lack of knowledge of the imbalance-related parameters, provided a mild persistency of excitation condition is satisfied.

Feedback attitude sliding mode regulation control of spacecraft using arm motion

NASA Astrophysics Data System (ADS)

Shi, Ye; Liang, Bin; Xu, Dong; Wang, Xueqian; Xu, Wenfu

2013-09-01

The problem of spacecraft attitude regulation based on the reaction of arm motion has attracted extensive attentions from both engineering and academic fields. Most of the solutions of the manipulator’s motion tracking problem just achieve asymptotical stabilization performance, so that these controllers cannot realize precise attitude regulation because of the existence of non-holonomic constraints. Thus, sliding mode control algorithms are adopted to stabilize the tracking error with zero transient process. Due to the switching effects of the variable structure controller, once the tracking error reaches the designed hyper-plane, it will be restricted to this plane permanently even with the existence of external disturbances. Thus, precise attitude regulation can be achieved. Furthermore, taking the non-zero initial tracking errors and chattering phenomenon into consideration, saturation functions are used to replace sign functions to smooth the control torques. The relations between the upper bounds of tracking errors and the controller parameters are derived to reveal physical characteristic of the controller. Mathematical models of free-floating space manipulator are established and simulations are conducted in the end. The results show that the spacecraft’s attitude can be regulated to the position as desired by using the proposed algorithm, the steady state error is 0.000 2 rad. In addition, the joint tracking trajectory is smooth, the joint tracking errors converges to zero quickly with a satisfactory continuous joint control input. The proposed research provides a feasible solution for spacecraft attitude regulation by using arm motion, and improves the precision of the spacecraft attitude regulation.

Office of Tracking and Data Acquisition. [deep space network and spacecraft tracking

NASA Technical Reports Server (NTRS)

1975-01-01

The Office of Tracking and Data Acquisition (OTDA) and its two worldwide tracking network facilities, the Spaceflight Tracking and Data Network and the Deep Space Network, are described. Other topics discussed include the NASA communications network, the tracking and data relay satellite system, other OTDA tracking activities, and OTDA milestones.

Spacecraft-spacecraft very long baseline interferometry. Part 1: Error modeling and observable accuracy

NASA Technical Reports Server (NTRS)

Edwards, C. D., Jr.; Border, J. S.

1992-01-01

In Part 1 of this two-part article, an error budget is presented for Earth-based delta differential one-way range (delta DOR) measurements between two spacecraft. Such observations, made between a planetary orbiter (or lander) and another spacecraft approaching that planet, would provide a powerful target-relative angular tracking data type for approach navigation. Accuracies of better than 5 nrad should be possible for a pair of spacecraft with 8.4-GHz downlinks, incorporating 40-MHz DOR tone spacings, while accuracies approaching 1 nrad will be possible if the spacecraft incorporate 32-GHz downlinks with DOR tone spacing on the order of 250 MHz; these accuracies will be available for the last few weeks or months of planetary approach for typical Earth-Mars trajectories. Operational advantages of this data type are discussed, and ground system requirements needed to enable spacecraft-spacecraft delta DOR observations are outlined. This tracking technique could be demonstrated during the final approach phase of the Mars '94 mission, using Mars Observer as the in-orbit reference spacecraft, if the Russian spacecraft includes an 8.4-GHz downlink incorporating DOR tones. Part 2 of this article will present an analysis of predicted targeting accuracy for this scenario.

Adaptive Neural Star Tracker Calibration for Precision Spacecraft Pointing and Tracking

NASA Technical Reports Server (NTRS)

Bayard, David S.

1996-01-01

The Star Tracker is an essential sensor for precision pointing and tracking in most 3-axis stabilized spacecraft. In the interest (of) improving pointing performance by taking advantage of dramatic increases in flight computer power and memory anticipated over the next decade, this paper investigates the use of a neural net for adaptive in-flight calibration of the Star Tracker.

Spacecraft Attitude Tracking and Maneuver Using Combined Magnetic Actuators

NASA Technical Reports Server (NTRS)

Zhou, Zhiqiang

2012-01-01

A paper describes attitude-control algorithms using the combination of magnetic actuators with reaction wheel assemblies (RWAs) or other types of actuators such as thrusters. The combination of magnetic actuators with one or two RWAs aligned with different body axis expands the two-dimensional control torque to three-dimensional. The algorithms can guarantee the spacecraft attitude and rates to track the commanded attitude precisely. A design example is presented for nadir-pointing, pitch, and yaw maneuvers. The results show that precise attitude tracking can be reached and the attitude- control accuracy is comparable with RWA-based attitude control. When there are only one or two workable RWAs due to RWA failures, the attitude-control system can switch to the control algorithms for the combined magnetic actuators with the RWAs without going to the safe mode, and the control accuracy can be maintained. The attitude-control algorithms of the combined actuators are derived, which can guarantee the spacecraft attitude and rates to track the commanded values precisely. Results show that precise attitude tracking can be reached, and the attitude-control accuracy is comparable with 3-axis wheel control.

Preliminary Orbit Determination System (PODS) for Tracking and Data Relay Satellite System (TDRSS)-tracked target Spacecraft using the homotopy continuation method

NASA Technical Reports Server (NTRS)

Kirschner, S. M.; Samii, M. V.; Broaddus, S. R.; Doll, C. E.

1988-01-01

The Preliminary Orbit Determination System (PODS) provides early orbit determination capability in the Trajectory Computation and Orbital Products System (TCOPS) for a Tracking and Data Relay Satellite System (TDRSS)-tracked spacecraft. PODS computes a set of orbit states from an a priori estimate and six tracking measurements, consisting of any combination of TDRSS range and Doppler tracking measurements. PODS uses the homotopy continuation method to solve a set of nonlinear equations, and it is particularly effective for the case when the a priori estimate is not well known. Since range and Doppler measurements produce multiple states in PODS, a screening technique selects the desired state. PODS is executed in the TCOPS environment and can directly access all operational data sets. At the completion of the preliminary orbit determination, the PODS-generated state, along with additional tracking measurements, can be directly input to the differential correction (DC) process to generate an improved state. To validate the computational and operational capabilities of PODS, tests were performed using simulated TDRSS tracking measurements for the Cosmic Background Explorer (COBE) satellite and using real TDRSS measurements for the Earth Radiation Budget Satellite (ERBS) and the Solar Mesosphere Explorer (SME) spacecraft. The effects of various measurement combinations, varying arc lengths, and levels of degradation of the a priori state vector on the PODS solutions were considered.

Gravity Probe-B (GP-B) Mission and Tracking, Telemetry and Control Subsystem Overview

NASA Technical Reports Server (NTRS)

Kennedy, Paul; Bell, Joseph L. (Technical Monitor)

2001-01-01

The National Aeronautics and Space Administration's (NASA) Marshall Space Flight Center (MSFC) in Huntsville, Alabama will launch the Gravity Probe B (GP-B) space experiment in the Fall of 2002. The GP-B spacecraft was developed to prove Einstein's theory of General Relativity. This paper will provide an overview of the GPB mission and will discuss the design, and test of the spacecraft Tracking, Telemetry and Control (TT&C) subsystem which incorporates NASA's latest generation standard transponder for use with the NASA Tracking and Data Relay Satellite System (TDRSS).

KSC-2013-1091

NASA Image and Video Library

2013-01-16

TITUSVILLE, Fla. – NASA's Tracking and Data Relay Satellite, TDRS-K, stands inside one half of the payload fairing as the spacecraft is encapsulated inside the Astrotech payload processing facility in Titusville, Fla., near NASA’s Kennedy Space Center. Launch of the TDRS-K on a United Launch Alliance Atlas V rocket is planned for January 29, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. Photo credit: NASA/Frankie Martin

KSC-2013-1093

NASA Image and Video Library

2013-01-16

TITUSVILLE, Fla. –NASA's Tracking and Data Relay Satellite, TDRS-K, stands inside one half of the payload fairing as the spacecraft is encapsulated inside the Astrotech payload processing facility in Titusville, Fla., near NASA’s Kennedy Space Center. Launch of the TDRS-K on a United Launch Alliance Atlas V rocket is planned for January 29, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. Photo credit: NASA/Frankie Martin

KSC-2013-1090

NASA Image and Video Library

2013-01-16

TITUSVILLE, Fla. – NASA's Tracking and Data Relay Satellite, TDRS-K, stands inside one half of the payload fairing as the spacecraft is encapsulated inside a United Launch Alliance Astrotech payload processing facility in Titusville, Fla., near NASA’s Kennedy Space Center. Launch of the TDRS-K on the Atlas V rocket is planned for January 29, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. Photo credit: NASA/Frankie Martin

Application of Tracking and Data Relay Satellite (TDRS) Differenced One-Way Doppler (DOWD) Tracking Data for Orbit Determination and Station Acquisition Support of User Spacecraft Without TDRS Compatible Transponders

NASA Technical Reports Server (NTRS)

Olszewski, A. D., Jr.; Wilcox, T. P.; Beckman, Mark

1996-01-01

Many spacecraft are launched today with only an omni-directional (omni) antenna and do not have an onboard Tracking and Data Relay Satellite (TDRS) transponder that is capable of coherently returning a carrier signal through TDRS. Therefore, other means of tracking need to be explored and used to adequately acquire the spacecraft. Differenced One-Way Doppler (DOWD) tracking data are very useful in eliminating the problems associated with the instability of the onboard oscillators when using strictly one-way Doppler data. This paper investigates the TDRS DOWD tracking data received by the Goddard Space Flight Center (GSFC) Flight Dynamics Facility (FDF) during the launch and early orbit phases for the the Interplanetary Physics Laboratory (WIND) and the National Oceanographic and Atmospheric Administration (NOAA)-J missions. In particular FDF personnel performed an investigation of the data residuals and made an assessment of the acquisition capabilities of DOWD-based solutions. Comparisons of DOWD solutions with existing data types were performed and analyzed in this study. The evaluation also includes atmospheric editing of the DOWD data and a study of the feasibility of solving for Doppler biases in an attempt to minimize error. Furthermore, by comparing the results from WIND and NOAA-J, an attempt is made to show the limitations involved in using DOWD data for the two different mission profiles. The techniques discussed in this paper benefit the launches of spacecraft that do not have TDRS transponders on board, particularly those launched into a low Earth orbit. The use of DOWD data is a valuable asset to missions which do not have a stable local oscillator to enable high-quality solutions from the one-way/return-link Doppler tracking data.

Modulating Retro-Reflectors for Space, Tracking, Acquisition and Ranging using Multiple Quantum Well Technology (Preprint)

DTIC Science & Technology

2002-01-01

feedback signals were derived from the motion of the platform rather than directly measured, though an actual spacecraft would likely utilize... large position error spikes due to target motion reversal. Of course, these tracking errors are highly dependent on the feedback gains chosen for the...Key Words: MQW Retromodulators, Modulating Retroreflector(s),Inter- spacecraft communications and navigation, space control

Tracking and data system support for the Pioneer project. Volume 1: Pioneer 10-prelaunch planning through second trajectory correction, 4 December 1969 - 1 April 1972

NASA Technical Reports Server (NTRS)

Siegmeth, A. J.; Purdue, R. E.; Ryan, R. E.

1973-01-01

The tracking and data system support of the launch, near-earth, and deep space phases of the Pioneer 10 mission, which sent a Pioneer spacecraft into a flyby of Jupiter that would eventually allow the spacecraft to escape the solar system is discussed. The support through the spacecraft's second trajectory correction is reported. During this period, scientific instruments aboard the spacecraft registered information relative to interplanetary particles and fields, and radiometric data generated by the network continued to improve knowledge of the celestial mechanics of the solar system. In addition to network support activity detail, network performance and special support activities are covered.

Determination of the System Mass and the Individual Masses of the Pluto System from New Horizons Radio Tracking

NASA Astrophysics Data System (ADS)

Hahn, Matthias; Pätzold, Martin; Andert, Tom; Bird, Michael K.; Tyler, Leonard G.; Linscott, Ivan; Hinson, Dave P.; Stern, Alan; Weaver, Hal; Olkin, Cathrin; Young, Leslie; Ennico, Kimberly

2015-11-01

One objective of the New Horizons Radio Science Experiment REX is the determination of the system mass and the individual masses of Pluto and Charon. About four weeks of two-way radio tracking centered around the closest approach of New Horizons to the Pluto system were processed. Major problems during the processing were caused by the small net forces of the spacecraft thruster activity, which produce extra Δv on the spacecraft motion superposed onto the continuously perturbed motion caused by the attracting forces of the Pluto system. The times of spacecraft thruster activity are known but the applied Δv needs to be specifically adjusted. No two-way tracking was available for the day of the flyby, but slots of REX one-way uplink tracking are used to cover the most important times near closest approach, e.g. during occultation entries and exits. This will help to separate the individual masses of Pluto and Charon from the system mass.

Application of GPS tracking techniques to orbit determination for TDRS

NASA Technical Reports Server (NTRS)

Haines, B. J.; Lichten, S. M.; Malla, R. P.; Wu, S. C.

1993-01-01

In this paper, we evaluate two fundamentally different approaches to TDRS orbit determination utilizing Global Positioning System (GPS) technology and GPS-related techniques. In the first, a GPS flight receiver is deployed on the TDRSS spacecraft. The TDRS ephemerides are determined using direct ranging to the GPS spacecraft, and no ground network is required. In the second approach, the TDRSS spacecraft broadcast a suitable beacon signal, permitting the simultaneous tracking of GPS and TDRSS satellites from a small ground network. Both strategies can be designed to meet future operational requirements for TDRS-2 orbit determination.

Tracking and data systems support for the Helios project. Volume 1: Project development through end of mission, phase 2

NASA Technical Reports Server (NTRS)

Goodwin, P. S.; Traxler, M. R.; Meeks, W. G.; Flanagan, F. M.

1976-01-01

The overall evolution of the Helios Project is summarized from its conception through to the completion of the Helios-1 mission phase 2. Beginning with the project objectives and concluding with the Helios-1 spacecraft entering its first superior conjunction (end of mission phase 2), descriptions of the project, the mission and its phases, international management and interfaces, and Deep Space Network-spacecraft engineering development in telemetry, tracking, and command systems to ensure compatibility between the U.S. Deep Space Network and the German-built spacecraft are included.

KSC-2009-3662

NASA Image and Video Library

2009-05-01

CAPE CANAVERAL, Fla. – At NASA Kennedy Space Center's Shuttle Landing Facility, the shipping container with the STSS Demonstrator SV-2spacecraft moves out of the U.S. Air Force C-17 aircraft. The spacecraft will be transferred to the Astrotech payload processing facility in Titusville, Fla. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Jack Pfaller (Approved for Public Release 09-MDA-4616 [27 May 09])

KSC-2009-3658

NASA Image and Video Library

2009-05-01

CAPE CANAVERAL, Fla. – The U.S. Air Force C-17 aircraft arrives at NASA Kennedy Space Center's Shuttle Landing Facility with its cargo of the STSS Demonstrator SV-2 spacecraft. The spacecraft will be transferred to the Astrotech payload processing facility in Titusville, Fla. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Jack Pfaller (Approved for Public Release 09-MDA-4616 [27 May 09])

KSC-2009-3660

NASA Image and Video Library

2009-05-01

CAPE CANAVERAL, Fla. – At NASA Kennedy Space Center's Shuttle Landing Facility, more equipment for the STSS Demonstrator SV-2 spacecraft is offloaded from the U.S. Air Force C-17 aircraft. The spacecraft will be transferred to the Astrotech payload processing facility in Titusville, Fla.The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Jack Pfaller (Approved for Public Release 09-MDA-4616 [27 May 09])

Noncoherent Doppler tracking: first flight results

NASA Astrophysics Data System (ADS)

DeBoy, Christopher C.; Robert Jensen, J.; Asher, Mark S.

2005-01-01

Noncoherent Doppler tracking has been devised as a means to achieve highly accurate, two-way Doppler measurements with a simple, transceiver-based communications system. This technique has been flown as an experiment on the Thermosphere, Ionosphere, Mesosphere, Energetics and Dynamics (TIMED) spacecraft, (launched 7 December 2001), as the operational technique for Doppler tracking on CONTOUR, and is baselined on several future deep space missions at JHU/APL. This paper reports on initial results from a series of successful tests of this technique between the TIMED spacecraft and NASA ground stations in the Deep Space Network. It also examines the advantages that noncoherent Doppler tracking and a transceiver-based system may offer to small satellite systems, including reduced cost, mass, and power.

It All Depends on Your Attitude.

ERIC Educational Resources Information Center

Kastner, Bernice

1992-01-01

Presents six learning exercises that introduce students to the mathematics used to control and track spacecraft attitude. Describes the geocentric system used for Earthbound location and navigation, the celestial sphere, the spacecraft-based celestial system, time-dependent angles, observer-fixed coordinate axes, and spacecraft rotational axes.…

Formation Flying Satellite Control Around the L2 Sun-Earth Libration Point

NASA Technical Reports Server (NTRS)

Hamilton, Nicholas H.; Folta, David; Carpenter, Russell; Bauer, Frank (Technical Monitor)

2002-01-01

This paper discusses the development of a linear control algorithm for formations in the vicinity of the L2 sun-Earth libration point. The development of a simplified extended Kalman filter is included as well. Simulations are created for the analysis of the stationkeeping and various formation maneuvers of the Stellar Imager mission. The simulations provide tracking error, estimation error, and control effort results. For formation maneuvering, the formation spacecraft track to within 4 meters of their desired position and within 1.5 millimeters per second of their desired zero velocity. The filter, with few exceptions, keeps the estimation errors within their three-sigma values. Without noise, the controller performs extremely well, with the formation spacecraft tracking to within several micrometers. Each spacecraft uses around 1 to 2 grams of propellant per maneuver, depending on the circumstances.

Finite-Time Attitude Tracking Control for Spacecraft Using Terminal Sliding Mode and Chebyshev Neural Network.

PubMed

An-Min Zou; Kumar, K D; Zeng-Guang Hou; Xi Liu

2011-08-01

A finite-time attitude tracking control scheme is proposed for spacecraft using terminal sliding mode and Chebyshev neural network (NN) (CNN). The four-parameter representations (quaternion) are used to describe the spacecraft attitude for global representation without singularities. The attitude state (i.e., attitude and velocity) error dynamics is transformed to a double integrator dynamics with a constraint on the spacecraft attitude. With consideration of this constraint, a novel terminal sliding manifold is proposed for the spacecraft. In order to guarantee that the output of the NN used in the controller is bounded by the corresponding bound of the approximated unknown function, a switch function is applied to generate a switching between the adaptive NN control and the robust controller. Meanwhile, a CNN, whose basis functions are implemented using only desired signals, is introduced to approximate the desired nonlinear function and bounded external disturbances online, and the robust term based on the hyperbolic tangent function is applied to counteract NN approximation errors in the adaptive neural control scheme. Most importantly, the finite-time stability in both the reaching phase and the sliding phase can be guaranteed by a Lyapunov-based approach. Finally, numerical simulations on the attitude tracking control of spacecraft in the presence of an unknown mass moment of inertia matrix, bounded external disturbances, and control input constraints are presented to demonstrate the performance of the proposed controller.

Spacecraft 2000

NASA Technical Reports Server (NTRS)

1986-01-01

The objective of the Workshop was to focus on the key technology area for 21st century spacecraft and the programs needed to facilitate technology development and validation. Topics addressed include: spacecraft systems; system development; structures and materials; thermal control; electrical power; telemetry, tracking, and control; data management; propulsion; and attitude control.

Mission Status at Aura Science Team MOWG Meeting: EOS Aura

NASA Technical Reports Server (NTRS)

Fisher, Dominic

2016-01-01

Presentation at the 24797-16 Earth Observing System (EOS) Aura Science Team Meeting (Mission Operations Work Group (MOWG)) at Rotterdam, Netherlands August 29, 2016. Presentation topics include mission summary, spacecraft subsystems summary, recent and planned activities, spacecraft anomalies, data capture, propellant usage and lifetime estimates, spacecraft maneuvers and ground track history, mission highlights and past spacecraft anomalies and reliability estimates.

Galileo Earth approach navigation using connected-element interferometer phase-delay tracking

NASA Technical Reports Server (NTRS)

Thurman, S. W.

1990-01-01

The application of a Connected-Element Interferometer (CEI) to the navigation of the Galileo spacecraft during its encounter with Earth in December 1990 is investigated. A CEI tracking demonstration is planned for the week of November 11 through 18, 1990, from 27 days to 20 days prior to Earth encounter on December 8. During this period, the spacecraft will be tracked daily with Deep Space Network Stations 13 and 15 at Goldstone. The purpose of this work is twofold: first, to establish and define the navigation performance expected during the tracking demonstration and, second, to study, in a more general sense, the sensitivity of orbit demonstration results obtained with CEI to the data density within CEI tracking passes and to important system parameters, such as baseline orientation errors and the phase-delay measurement accuracy. Computer simulation results indicate that the use of CEI data, coupled with conventional range and Doppler data, may reduce the uncertainty in the declination of the spacecraft's incoming trajectory by 15 to 66 percent compared with the operational solution using range and Doppler data only. The level of improvement depends upon the quantity and quality of the CEI data.

Refined gravity determination at small bodies through landing probes

NASA Astrophysics Data System (ADS)

Bellerose, J.

2012-02-01

Very small objects of the near-Earth population have not been visited to date, and may be among the next targets for human exploration. As density is a strong indication of the body origin and intrinsic properties, determining the mass is one of the most important goals. The past missions to Eros and Itokawa resulted in mass and density estimates to less than five percent error, allowing precise mission planning while giving new insights on the body structure. Current mass determination techniques have limitations in the low gravity regime, and spacecraft tracking at very small asteroids is challenging. We investigate the constraints on measuring the mass at very small near-Earth objects, and their consequences on proximity operation planning. An alternative option to spacecraft radio tracking is to use surface probes. The near-surface and landing dynamics can be observed and tracked by the host spacecraft, providing higher resolution measurements of the NEA gravity pull. We show analytical methods to estimate the performance of given proximity operations, and simulations of spacecraft and probe dynamics at NEAs less than 100 m in diameter.

Tracking and data system support for the Pioneer project. Pioneers 6-9, extended missions: 1 July 1972 - 1 July 1973, volume 12

NASA Technical Reports Server (NTRS)

Miller, R. B.

1974-01-01

The Tracking and Data System supported the deep space phases of the Pioneer 6, 7, 8, and 9 missions, with two spacecraft in an inward trajectory and two spacecraft in an outward trajectory from the earth in heliocentric orbits. During the period of this report, scientific instruments aboard each of the spacecraft continued to register information relative to interplanetary particles and fields, and radiometric data generated by the network continued to contribute to knowledge of the celestial mechanics of the solar system. In addition, to network support activity detail, network performance and special support activities are covered.

Early results of the ionospheric experiment of the Apollo-Soyuz Test Project

NASA Technical Reports Server (NTRS)

Grossi, M. D.; Gay, R. H.

1976-01-01

A description is presented of a spacecraft-to-spacecraft Doppler-tracking experiment which was performed by the Smithsonian Astrophysical Observatory on the occasion of the Apollo-Soyuz Test Project (ASTP). The experiment involved the measurement of the relative velocity between the ASTP docking module and the Apollo command service module by a Doppler-tracking method. The objectives of the ionospheric experiment include the measurement of the time changes of the columnar electron content between the two spacecraft. The obtained data can provide a basis for the determination of the horizontal gradients of electron density at the height of 220 km.

Tracking and data system support for the pioneer project. Volume 11 Pioneers 6-9. Extended missions: 1 July 1971 - 1 July 1973

NASA Technical Reports Server (NTRS)

Renzetti, N. A.; Siegmeth, A. J.

1973-01-01

The Tracking and Data System supported the deep space phases of the Pioneer 6, 7, 8, and 9 missions, with two spacecraft in an inward trajectory and two spacecraft in an outward trajectory from the earth in heliocentric orbits. Scientific instruments aboard each of the spacecraft continued to register information relative to interplanetary particles and fields, and radio metric data generated by the network continued to improve our knowledge of the celestial mechanics of the solar system. In addition to network support activity detail, network performance and special support activities are covered.

A Nonlinear Spacecraft Attitude Controller and Observer with an Unknown Constant Gyro Bias and Gyro Noise

NASA Technical Reports Server (NTRS)

Deutschmann, Julie; Sanner, Robert M.

2001-01-01

A nonlinear control scheme for attitude control of a spacecraft is combined with a nonlinear gyro bias observer for the case of constant gyro bias, in the presence of gyro noise. The observer bias estimates converge exponentially to a mean square bound determined by the standard deviation of the gyro noise. The resulting coupled, closed loop dynamics are proven to be globally stable, with asymptotic tracking which is also mean square bounded. A simulation of the proposed observer-controller design is given for a rigid spacecraft tracking a specified, time-varying attitude sequence to illustrate the theoretical claims.

KSC-2009-3663

NASA Image and Video Library

2009-05-01

CAPE CANAVERAL, Fla. – At NASA Kennedy Space Center's Shuttle Landing Facility, the shipping container with the STSS Demonstrator SV-2spacecraft has been moved out of the U.S. Air Force C-17 aircraft. The spacecraft will be transferred to the Astrotech payload processing facility in Titusville, Fla. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Jack Pfaller (Approved for Public Release 09-MDA-4616 [27 May 09])

KSC-2009-3661

NASA Image and Video Library

2009-05-01

CAPE CANAVERAL, Fla. – At NASA Kennedy Space Center's Shuttle Landing Facility, the shipping container with the STSS Demonstrator SV-2spacecraft waits to be offloaded from the U.S. Air Force C-17 aircraft. The spacecraft will be transferred to the Astrotech payload processing facility in Titusville, Fla. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Jack Pfaller (Approved for Public Release 09-MDA-4616 [27 May 09])

Radiometric Spacecraft Tracking for Deep Space Navigation

NASA Technical Reports Server (NTRS)

Lanyi, Gabor E.; Border, James S.; Shin, Dong K.

2008-01-01

Interplanetary spacecraft navigation relies on three types of terrestrial tracking observables.1) Ranging measures the distance between the observing site and the probe. 2) The line-of-sight velocity of the probe is inferred from Doppler-shift by measuring the frequency shift of the received signal with respect to the unshifted frequency. 3) Differential angular coordinates of the probe with respect to natural radio sources are nominally obtained via a differential delay technique of (Delta) DOR (Delta Differential One-way Ranging). The accuracy of spacecraft coordinate determination depends on the measurement uncertainties associated with each of these three techniques. We evaluate the corresponding sources of error and present a detailed error budget.

KSC-2009-3659

NASA Image and Video Library

2009-05-01

CAPE CANAVERAL, Fla. – At NASA Kennedy Space Center's Shuttle Landing Facility, workers move STSS Demonstrator SV-2 spacecraft equipment out of the cargo hold of the U.S. Air Force C-17 aircraft. The spacecraft will be transferred to the Astrotech payload processing facility in Titusville, Fla. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Jack Pfaller (Approved for Public Release 09-MDA-4616 [27 May 09])

Attitude guidance and tracking for spacecraft with two reaction wheels

NASA Astrophysics Data System (ADS)

Biggs, James D.; Bai, Yuliang; Henninger, Helen

2018-04-01

This paper addresses the guidance and tracking problem for a rigid-spacecraft using two reaction wheels (RWs). The guidance problem is formulated as an optimal control problem on the special orthogonal group SO(3). The optimal motion is solved analytically as a function of time and is used to reduce the original guidance problem to one of computing the minimum of a nonlinear function. A tracking control using two RWs is developed that extends previous singular quaternion stabilisation controls to tracking controls on the rotation group. The controller is proved to locally asymptotically track the generated reference motions using Lyapunov's direct method. Simulations of a 3U CubeSat demonstrate that this tracking control is robust to initial rotation errors and angular velocity errors in the controlled axis. For initial angular velocity errors in the uncontrolled axis and under significant disturbances the control fails to track. However, the singular tracking control is combined with a nano-magnetic torquer which simply damps the angular velocity in the uncontrolled axis and is shown to provide a practical control method for tracking in the presence of disturbances and initial condition errors.

Parameter estimation of a three-axis spacecraft simulator using recursive least-squares approach with tracking differentiator and Extended Kalman Filter

NASA Astrophysics Data System (ADS)

Xu, Zheyao; Qi, Naiming; Chen, Yukun

2015-12-01

Spacecraft simulators are widely used to study the dynamics, guidance, navigation, and control of a spacecraft on the ground. A spacecraft simulator can have three rotational degrees of freedom by using a spherical air-bearing to simulate a frictionless and micro-gravity space environment. The moment of inertia and center of mass are essential for control system design of ground-based three-axis spacecraft simulators. Unfortunately, they cannot be known precisely. This paper presents two approaches, i.e. a recursive least-squares (RLS) approach with tracking differentiator (TD) and Extended Kalman Filter (EKF) method, to estimate inertia parameters. The tracking differentiator (TD) filter the noise coupled with the measured signals and generate derivate of the measured signals. Combination of two TD filters in series obtains the angular accelerations that are required in RLS (TD-TD-RLS). Another method that does not need to estimate the angular accelerations is using the integrated form of dynamics equation. An extended TD (ETD) filter which can also generate the integration of the function of signals is presented for RLS (denoted as ETD-RLS). States and inertia parameters are estimated simultaneously using EKF. The observability is analyzed. All proposed methods are illustrated by simulations and experiments.

SLR tracking of GPS-35

NASA Technical Reports Server (NTRS)

Pavlis, Erricos C.

1994-01-01

An experiment was designed to launch a corner cube retroreflector array on one of the Global Positioning Satellites (GPS). The launch on Aug. 31, 1993 ushered in the era of SLR tracking of GPS spacecraft. Once the space operations group finished the check-out procedures for the new satellite, the agreed upon SLR sites were allowed to track it. The first site to acquire GPS-35 was the Russian system at Maidanak and closely after the MLRS system at McDonald Observatory, Texas. The laser tracking network is currently tracking the GPS spacecraft known as GPS-35 or PRN 5 with great success. From the NASA side there are five stations that contribute data regularly and nearly as many from the international partners. Upcoming modifications to the ground receivers will allow for a further increase in the tracking capabilities of several additional sites and add some desperately needed southern hemisphere tracking. We are analyzing the data and are comparing SLR-derived orbits to those determined on the basis of GPS radiometric data.

Lunar Orbiter 4 - Photographic Mission Summary. Volume 1

NASA Technical Reports Server (NTRS)

1968-01-01

Photographic summary report of Lunar Orbiter 4 mission. The fourth of five Lunar Orbiter spacecraft was successfully launched from Launch Complex 13 at the Air Force Eastern Test Range by an Atlas-Agena launch vehicle at 22:25 GMT on May 4, 1967. Tracking data from the Cape Kennedy and Grand Bahama tracking stations were used to control and guide the launch vehicle during Atlas powered flight. The Agena-spacecraft combination was boosted to the proper coast ellipse by the Atlas booster prior to separation. Final maneuvering and acceleration to the velocity required to maintain the 100-nauticalmile- altitude Earth orbit was controlled by the preset on-board Agena computer. In addition, the Agena computer determined the maneuver and engine-burn period required to inject the spacecraft on the cislunar trajectory 20 minutes after launch. Tracking data from the downrange stations and the Johannesburg, South Africa station were used to monitor the boost trajectory.

Lunar Orbiter 5. Photographic Mission Summary. Volume 1

NASA Technical Reports Server (NTRS)

1968-01-01

Selected photographs and mission summary of Lunar Orbiter 5. The last of five Lunar Orbiter spacecraft was successfully launched from Launch Complex 13 at the Air Force Eastern Test Range by an Atlas-Agena launch vehicle at 22:33 GMT on August 1, 1967. Tracking data from the Cape Kennedy and Grand Bahama tracking stations were used to control and guide the launch vehicle during Atlas powered flight. The Agena-spacecraft combination was boosted to the proper coast ellipse by the Atlas booster prior to separation. Final maneuvering and acceleration to the velocity required to maintain the 100-nautical-mile-altitude Earth orbit were controlled by the preset on-board Agena computer. In addition, the Agena computer determined the maneuver and engine-bum period required to inject the spacecraft on the cislunar trajectory about 33 minutes after launch. Tracking data from the downrange stations and the Johannesburg, South Africa station were used to monitor the boost trajectory.

Lunar Orbiter 3 - Photographic Mission Summary

NASA Technical Reports Server (NTRS)

1968-01-01

Systems performance, lunar photography, and launch operations of Lunar Orbiter 3 photographic mission. The third of five Lunar Orbiter spacecraft was successfully launched from Launch Complex 13 at the Air Force Eastern Test Range by an Atlas-Agena launch vehicle at 01:17 GMT on February 5,1967. Tracking data from the Cape Kennedy and Grand Bahama tracking stations were used to control and guide the launch vehicle during Atlas powered flight. The Agena-spacecraft combination was boosted to the proper coast ellipse by the Atlas booster prior to separation. Final 1 maneuvering and acceleration to the velocity required to maintain the 100-nautical-milealtitude Earth orbit was controlled by the preset on-board Agena computer. In addition, the Agena computer determined the maneuver and engine-burn period required to inject the spacecraft on the cislunar trajectory 20 minutes after launch. Tracking data from the downrange stations and the Johannesburg, South Africa station were used to monitor the entire boost trajectory.

Extended state observer based robust adaptive control on SE(3) for coupled spacecraft tracking maneuver with actuator saturation and misalignment

NASA Astrophysics Data System (ADS)

Zhang, Jianqiao; Ye, Dong; Sun, Zhaowei; Liu, Chuang

2018-02-01

This paper presents a robust adaptive controller integrated with an extended state observer (ESO) to solve coupled spacecraft tracking maneuver in the presence of model uncertainties, external disturbances, actuator uncertainties including magnitude deviation and misalignment, and even actuator saturation. More specifically, employing the exponential coordinates on the Lie group SE(3) to describe configuration tracking errors, the coupled six-degrees-of-freedom (6-DOF) dynamics are developed for spacecraft relative motion, in which a generic fully actuated thruster distribution is considered and the lumped disturbances are reconstructed by using anti-windup technique. Then, a novel ESO, developed via second order sliding mode (SOSM) technique and adding linear correction terms to improve the performance, is designed firstly to estimate the disturbances in finite time. Based on the estimated information, an adaptive fast terminal sliding mode (AFTSM) controller is developed to guarantee the almost global asymptotic stability of the resulting closed-loop system such that the trajectory can be tracked with all the aforementioned drawbacks addressed simultaneously. Finally, the effectiveness of the controller is illustrated through numerical examples.

KSC-02pp1641

NASA Image and Video Library

2002-10-18

KENNEDY SPACE CENTER, FLA. -- Workers supervise the move of the suspended TDRS-J spacecraft towards a workstand in the Spacecraft Assembly and Encapsulation Facility-2 (SAEF-2) for final checkout and processing before launch, currently targeted for Nov. 20. TDRS-J is the third in the current series of three Tracking and Data Relay Satellites designed to replenish the existing on-orbit fleet of six spacecraft, the first of which was launched in 1983. The Tracking and Data Relay Satellite System is the primary source of space-to-ground voice, data and telemetry for the Space Shuttle. It also provides communications with the International Space Station and scientific spacecraft in low-earth orbit, such as the Hubble Space Telescope, and launch support for some expendable vehicles. This new advanced series of satellites will extend the availability of TDRS communications services until approximately 2017.

KSC-02pp1643

NASA Image and Video Library

2002-10-18

KENNEDY SPACE CENTER, FLA. -- Workers supervise the placement of the TDRS-J spacecraft onto a workstand in the Spacecraft Assembly and Encapsulation Facility-2 (SAEF-2) for final checkout and processing before launch, currently targeted for Nov. 20. TDRS-J is the third in the current series of three Tracking and Data Relay Satellites designed to replenish the existing on-orbit fleet of six spacecraft, the first of which was launched in 1983. The Tracking and Data Relay Satellite System is the primary source of space-to-ground voice, data and telemetry for the Space Shuttle. It also provides communications with the International Space Station and scientific spacecraft in low-earth orbit, such as the Hubble Space Telescope, and launch support for some expendable vehicles. This new advanced series of satellites will extend the availability of TDRS communications services until approximately 2017.

KSC-02pd1575

NASA Image and Video Library

2002-10-18

KENNEDY SPACE CENTER, FLA. - Workers attach the container with the TDRS-J spacecraft inside to an overhead crane. The container will be placed on a transporter and taken to the Spacecraft Assembly and Encapsulation Facility-2 (SAEF-2). TDRS-J is the third in the current series of three Tracking and Data Relay Satellites designed to replenish the existing on-orbit fleet of six spacecraft, the first of which was launched in 1983. The Tracking and Data Relay Satellite System is the primary source of space-to-ground voice, data and telemetry for the Space Shuttle. It also provides communications with the International Space Station and scientific spacecraft in low-earth orbit such as the Hubble Space Telescope, and launch support for some expendable vehicles. This new advanced series of satellites will extend the availability of TDRS communications services until approximately 2017.

Advanced Navigation Strategies For Asteroid Sample Return Missions

NASA Technical Reports Server (NTRS)

Getzandanner, K.; Bauman, J.; Williams, B.; Carpenter, J.

2010-01-01

Flyby and rendezvous missions to asteroids have been accomplished using navigation techniques derived from experience gained in planetary exploration. This paper presents analysis of advanced navigation techniques required to meet unique challenges for precision navigation to acquire a sample from an asteroid and return it to Earth. These techniques rely on tracking data types such as spacecraft-based laser ranging and optical landmark tracking in addition to the traditional Earth-based Deep Space Network radio metric tracking. A systematic study of navigation strategy, including the navigation event timeline and reduction in spacecraft-asteroid relative errors, has been performed using simulation and covariance analysis on a representative mission.

Interfacing with USSTRATCOM and UTTR during Stardust Earth Return

NASA Technical Reports Server (NTRS)

Jefferson, David C.; Baird, Darren T.; Cangahuala, Laureano A.; Lewis, George D.

2006-01-01

The Stardust Sample Return Capsule separated from the main spacecraft four hours prior to atmospheric entry. Between this time and the time at which the SRC touched down at the Utah Test and Training Range, two organizations external to JPL were involved in tracking the Sample Return Capsule. Orbit determination for the Stardust spacecraft during deep space cruise, the encounters of asteroid Annefrank and comet Wild 2, and the final approach to Earth used X-band radio metric Doppler and range data obtained through the Deep Space Network. The SRC lacked the electronics needed for coherently transponded radio metric tracking, so the DSN was not able to track the SRC after it separated from the main spacecraft. Although the expected delivery accuracy at atmospheric entry was well within the capability needed to target the SRC to the desired ground location, it was still desirable to obtain direct knowledge of the SRC trajectory in case of anomalies. For this reason U.S. Strategic Command was engaged to track the SRC between separation and atmospheric entry. Once the SRC entered the atmosphere, ground sensors at UTTR were tasked to acquire the descending SRC and maintain track during the descent in order to determine the landing location, to which the ground recovery team was then directed. This paper discusses organizational interfaces, data products, and delivery schedules, and the actual tracking operations are described.

KSC-2009-2816

NASA Image and Video Library

2009-04-21

CAPE CANAVERAL, Fla. – On Launch Pad 17-B at Cape Canaveral Air Force Station, a worker attaches solid rocket boosters to a Delta II rocket for launch of the STSS Demonstrator spacecraft. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency on July 29. Photo credit: NASA/Kim Shiflett

KSC-2009-3667

NASA Image and Video Library

2009-05-01

CAPE CANAVERAL, Fla. – The STSS Demonstrator SV-2spacecraft arrives at the Astrotech payload processing facility in Titusville, Fla. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Jack Pfaller (Approved for Public Release 09-MDA-4616 [27 May 09])

KSC-2009-2815

NASA Image and Video Library

2009-04-21

CAPE CANAVERAL, Fla. – On Launch Pad 17-B at Cape Canaveral Air Force Station, solid rocket boosters are attached to a Delta II rocket for launch of the STSS Demonstrator spacecraft. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency on July 29. Photo credit: NASA/Kim Shiflett

KSC-2009-2819

NASA Image and Video Library

2009-04-21

CAPE CANAVERAL, Fla. – On Launch Pad 17-B at Cape Canaveral Air Force Station, solid rocket boosters are installed on a Delta II rocket for launch of the STSS Demonstrator spacecraft. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency on July 29. Photo credit: NASA/Kim Shiflett

Conceptual Design of a Communication-Based Deep Space Navigation Network

NASA Technical Reports Server (NTRS)

Anzalone, Evan J.; Chuang, C. H.

2012-01-01

As the need grows for increased autonomy and position knowledge accuracy to support missions beyond Earth orbit, engineers must push and develop more advanced navigation sensors and systems that operate independent of Earth-based analysis and processing. Several spacecraft are approaching this problem using inter-spacecraft radiometric tracking and onboard autonomous optical navigation methods. This paper proposes an alternative implementation to aid in spacecraft position fixing. The proposed method Network-Based Navigation technique takes advantage of the communication data being sent between spacecraft and between spacecraft and ground control to embed navigation information. The navigation system uses these packets to provide navigation estimates to an onboard navigation filter to augment traditional ground-based radiometric tracking techniques. As opposed to using digital signal measurements to capture inherent information of the transmitted signal itself, this method relies on the embedded navigation packet headers to calculate a navigation estimate. This method is heavily dependent on clock accuracy and the initial results show the promising performance of a notional system.

KSC-02pd1577

NASA Image and Video Library

2002-10-18

KENNEDY SPACE CENTER, FLA. - A worker ties down the container with the TDRS-J spacecraft onto a transport vehicle. TDRS-J is the third in the current series of three Tracking and Data Relay Satellites designed to replenish the existing on-orbit fleet of six spacecraft, the first of which was launched in 1983. The Tracking and Data Relay Satellite System is the primary source of space-to-ground voice, data and telemetry for the Space Shuttle. It also provides communications with the International Space Station and scientific spacecraft in low-earth orbit such as the Hubble Space Telescope, and launch support for some expendable vehicles. This new advanced series of satellites will extend the availability of TDRS communications services until approximately 2017.

TDRS-L Pre-Launch Press Conference

NASA Image and Video Library

2014-01-21

CAPE CANAVERAL, Fla. – During a news conference at NASA's Kennedy Space Center in Florida, agency and contractor officials discussed preparations for the launch of NASA's Tracking and Data Relay Satellite, or TDRS-L, spacecraft. Participants included Andy Kopito, Civil Space Programs director for Boeing Space & Intelligence Systems in El Segundo, Calif. The TDRS-L spacecraft is the second of three new satellites designed to ensure vital operational continuity for NASA by expanding the lifespan of the Tracking and Data Relay Satellite System TDRSS fleet, which consists of eight satellites in geosynchronous orbit. The spacecraft provide tracking, telemetry, command and high bandwidth data return services for numerous science and human exploration missions orbiting Earth. These include NASA's Hubble Space Telescope and the International Space Station. TDRS-L has a high-performance solar panel designed for more spacecraft power to meet the growing S-band communications requirements. TDRSS is one of NASA Space Communication and Navigation’s SCaN three networks providing space communications to NASA’s missions. For more information more about TDRS-L, visit: http://www.nasa.gov/tdrs To learn more about SCaN, visit: www.nasa.gov/scan Photo credit: NASA/Frankie Martin

Spacecraft system study: A study to define the impact of laser communication systems on their host spacecraft

NASA Technical Reports Server (NTRS)

1984-01-01

The mutual influence of a laser communication system and its host spacecraft and the degree to which the mutual influence limited acquisition, tracking and pointing processes were investigated. A laser klink between a low earth orbiting (LEO) satellite and a geosynchronous earth orbiting (GEO) satellite was used as a baseline. The laser link between satellites was a generic channel transferring 500 Mbps data from the LEO to GEO using the GaAlAs laser as the laser light source. Major aspects of pointing and tracking with a satelliteborne optical system were evaluated including: (1) orbital aspects such as spacecraft relative motions, point ahead, and Sun snd Moon optical noise; (2) burst errors introduced by the electronic and optical noise levels; (3) servo system design and configurations, and the noise sources such as, sensor noise, base motion disturbances, gimbal friction torque noise; (4) an evaluation of the tracking and beacon link and the type of sensors used; (5) the function of the acquisition procedure and an evaluation of the sensors employed; and (6) an estimate of the size, weight and power needed for the satellite system.

Use of Faraday-rotation data from beacon satellites to determine ionospheric corrections for interplanetary spacecraft navigation

NASA Technical Reports Server (NTRS)

Royden, H. N.; Green, D. W.; Walson, G. R.

1981-01-01

Faraday-rotation data from the linearly polarized 137-MHz beacons of the ATS-1, SIRIO, and Kiku-2 geosynchronous satellites are used to determine the ionospheric corrections to the range and Doppler data for interplanetary spacecraft navigation. The JPL operates the Deep Space Network of tracking stations for NASA; these stations monitor Faraday rotation with dual orthogonal, linearly polarized antennas, Teledyne polarization tracking receivers, analog-to-digital converter/scanners, and other support equipment. Computer software examines the Faraday data, resolves the pi ambiguities, constructs a continuous Faraday-rotation profile and converts the profile to columnar zenith total electron content at the ionospheric reference point; a second program computes the line-of-sight ionospheric correction for each pass of the spacecraft over each tracking complex. Line-of-sight ionospheric electron content using mapped Faraday-rotation data is compared with that using dispersive Doppler data from the Voyager spacecraft; a difference of about 0.4 meters, or 5 x 10 to the 16th electrons/sq m is obtained. The technique of determining the electron content of interplanetary plasma by subtraction of the ionospheric contribution is demonstrated on the plasma torus surrounding the orbit of Io.

Alouette-ISIS program summary

NASA Technical Reports Server (NTRS)

Jackson, John E.

1986-01-01

The Alouette-ISIS program was a joint undertaking between Canada and the United States. Canada provided the Alouette and ISIS spacecraft, data acquisition, and satellite control. The USA provided launch capability, satellite tracking, and data acquisition. Brief descriptions of the six spacecraft and of the investigations on each spacecraft are given. The Alouette-ISIS bibliography, order alphabetically by first author's name, is contained.

Gravitational-wave bursts from the nuclei of distant galaxies and quasars: Proposal for detection using Doppler tracking of interplanetary spacecraft

NASA Technical Reports Server (NTRS)

Thorne, K. S.; Braginsky, V. B.

1974-01-01

Supermassive black holes which exist in the nuclei of many quasars and galaxies are examined along with the collapse which forms these holes and subsequent collisions between them which produce strong, broad-band bursts of gravitational waves. Such bursts might arrive at earth as often as 50 times per year--or as rarely as once each 300 years. The detection of such bursts with dual-frequency Doppler tracking of interplanetary spacecraft is considered.

KSC-2009-4627

NASA Image and Video Library

2009-07-23

CAPE CANAVERAL, Fla. – In the Astrotech payload processing facility in Titusville, Fla. , technicians monitor the STSS Demonstrator SV-1 spacecraft as it is lowered to the orbital insertion system. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Tim Jacobs (Approved for Public Release 09-MDA-4800 [30 July 09] )

KSC-2009-2818

NASA Image and Video Library

2009-04-21

CAPE CANAVERAL, Fla. – On Launch Pad 17-B at Cape Canaveral Air Force Station, workers monitor the placement of a solid rocket booster on a Delta II rocket for launch of the STSS Demonstrator spacecraft. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency on July 29. Photo credit: NASA/Kim Shiflett

KSC-2009-3666

NASA Image and Video Library

2009-05-01

CAPE CANAVERAL, Fla. – A flatbed truck carrying the STSS Demonstrator SV-2spacecraft arrives at the Astrotech payload processing facility in Titusville, Fla. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Jack Pfaller (Approved for Public Release 09-MDA-4616 [27 May 09])

KSC-2009-4625

NASA Image and Video Library

2009-07-23

CAPE CANAVERAL, Fla. – In the Astrotech payload processing facility in Titusville, Fla. , the STSS Demonstrator SV-1 spacecraft is lowered toward the orbital insertion system. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Tim Jacobs (Approved for Public Release 09-MDA-4800 [30 July 09] )

KSC-2009-4617

NASA Image and Video Library

2009-06-25

CAPE CANAVERAL, Fla. – The flatbed truck with the SV-1 cargo of the STSS Demonstrator spacecraft arrives at the Astrotech payload processing facility in Titusville, Fla. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Kim Shiflett (Approved for Public Release 09-MDA-4804 [4 Aug 09] )

KSC-2009-4626

NASA Image and Video Library

2009-07-23

CAPE CANAVERAL, Fla. – In the Astrotech payload processing facility in Titusville, Fla. , technicians monitor the STSS Demonstrator SV-1 spacecraft as it is lowered to the orbital insertion system. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Tim Jacobs (Approved for Public Release 09-MDA-4800 [30 July 09] )

KSC-2009-4622

NASA Image and Video Library

2009-07-23

CAPE CANAVERAL, Fla. – In the Astrotech payload processing facility in Titusville, Fla. , the STSS Demonstrator SV-1 spacecraft is being moved to a stand. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Tim Jacobs (Approved for Public Release 09-MDA-4800 [30 July 09] )

KSC-2009-3668

NASA Image and Video Library

2009-05-01

CAPE CANAVERAL, Fla. – The STSS Demonstrator SV-2spacecraft is moved inside a building at the Astrotech payload processing facility in Titusville, Fla. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Jack Pfaller (Approved for Public Release 09-MDA-4616 [27 May 09])

KSC-2009-4618

NASA Image and Video Library

2009-06-25

CAPE CANAVERAL, Fla. – The SV-1 cargo of the STSS Demonstrator spacecraft is moved into the Astrotech payload processing facility in Titusville, Fla. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Kim Shiflett (Approved for Public Release 09-MDA-4804 [4 Aug 09] )

KSC-2009-4628

NASA Image and Video Library

2009-07-23

CAPE CANAVERAL, Fla. – In the Astrotech payload processing facility in Titusville, Fla. , the STSS Demonstrator SV-1 spacecraft is lowered to the orbital insertion system. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Tim Jacobs (Approved for Public Release 09-MDA-4800 [30 July 09] )

KSC-2009-4624

NASA Image and Video Library

2009-07-23

CAPE CANAVERAL, Fla. – In the Astrotech payload processing facility in Titusville, Fla. , the STSS Demonstrator SV-1 spacecraft is moved toward the orbital insertion system. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Tim Jacobs (Approved for Public Release 09-MDA-4800 [30 July 09] )

KSC-2009-4619

NASA Image and Video Library

2009-07-23

CAPE CANAVERAL, Fla. – The shipping crate is being removed from the STSS Demonstrator SV-1 spacecraft in the Astrotech payload processing facility in Titusville, Fla. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Tim Jacobs (Approved for Public Release 09-MDA-4800 [30 July 09] )

KSC-2009-2817

NASA Image and Video Library

2009-04-21

CAPE CANAVERAL, Fla. – On Launch Pad 17-B at Cape Canaveral Air Force Station, a worker monitors the placement of a solid rocket booster on a Delta II rocket for launch of the STSS Demonstrator spacecraft. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency on July 29. Photo credit: NASA/Kim Shiflett

KSC-2009-4623

NASA Image and Video Library

2009-07-23

CAPE CANAVERAL, Fla. – In the Astrotech payload processing facility in Titusville, Fla. , the STSS Demonstrator SV-1 spacecraft is lowered onto a stand. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Tim Jacobs (Approved for Public Release 09-MDA-4800 [30 July 09] )

KSC-2009-4616

NASA Image and Video Library

2009-06-25

CAPE CANAVERAL, Fla. – The flatbed truck with the SV-1 cargo of the STSS Demonstrator spacecraft arrives at the Astrotech payload processing facility in Titusville, Fla. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Kim Shiflett (Approved for Public Release 09-MDA-4804 [4 Aug 09] )

KSC-2009-4620

NASA Image and Video Library

2009-07-23

CAPE CANAVERAL, Fla. – In the Astrotech payload processing facility in Titusville, Fla. , the STSS Demonstrator SV-1 spacecraft is lifted from its shipping crate. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Tim Jacobs (Approved for Public Release 09-MDA-4800 [30 July 09] )

KSC-2009-4621

NASA Image and Video Library

2009-07-23

CAPE CANAVERAL, Fla. – In the Astrotech payload processing facility in Titusville, Fla. , the STSS Demonstrator SV-1 spacecraft is lifted clear from its shipping crate. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Tim Jacobs (Approved for Public Release 09-MDA-4800 [30 July 09] )

KSC-2009-4630

NASA Image and Video Library

2009-07-23

CAPE CANAVERAL, Fla. – In the Astrotech payload processing facility in Titusville, Fla. , technicians get ready to remove the overhead crane from the STSS Demonstrator SV-1 spacecraft. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Tim Jacobs (Approved for Public Release 09-MDA-4800 [30 July 09] )

Tracking and data relay satellite fault isolation and correction using PACES: Power and attitude control expert system

NASA Technical Reports Server (NTRS)

Erikson, Carol-Lee; Hooker, Peggy

1989-01-01

The Power and Attitude Control Expert System (PACES) is an object oriented and rule based expert system which provides spacecraft engineers with assistance in isolating and correcting problems within the Power and Attitude Control Subsystems of the Tracking and Data Relay Satellites (TDRS). PACES is designed to act in a consultant role. It will not interface to telemetry data, thus preserving full operator control over spacecraft operations. The spacecraft engineer will input requested information. This information will include telemetry data, action being performed, problem characteristics, spectral characteristics, and judgments of spacecraft functioning. Questions are answered either by clicking on appropriate responses (for text), or entering numeric values. A context sensitive help facility allows access to additional information when the user has difficulty understanding a question or deciding on an answer. The major functionality of PACES is to act as a knowledge rich system which includes block diagrams, text, and graphics, linked using hypermedia techniques. This allows easy movement among pieces of the knowledge. Considerable documentation of the spacecraft Power and Attitude Control Subsystems is embedded within PACES. The development phase of TDRSS expert system technology is intended to provide NASA with the necessary expertise and capability to define requirements, evaluate proposals, and monitor the development progress of a highly competent expert system for NASA's Tracking and Data Relay Satellite Program.

Gravity and Macro-Model Tuning for the Geosat Follow-on Spacecraft

NASA Technical Reports Server (NTRS)

Lemoine, Frank G.; Rowlands, David D.; Marr, Gregory C.; Zelensky, Nikita P.; Luthcke, Scott B.; Cox, Christopher M.

1999-01-01

The US Navy's GEOSAT Follow-On (GFO) spacecraft was launched on February 10, 1998 and the primary objective of the mission was to map the oceans using a radar altimeter. The spacecraft tracking complement consisted of GPS receivers, a laser retroreflector and Doppler beacons. Since the GPS receivers have not yet returned reliable data, the only means of providing high-quality precise orbits has been though satellite laser ranging (SLR). The spacecraft has been tracked by the international satellite laser ranging network since April 22, 1998, and an average of 7.4 passes per day have been obtained from US and participating foreign stations. Since the predicted radial orbit error due to the gravity field is two to three cm, the largest contributor to the high SLR residuals (7-10 cm RMS for five day arcs) is the mismodelling of the non-conservative forces, not withstanding the development of a three-dimensional eight-panel model and an analytical attitude model for the GFO spacecraft. The SLR residuals show a clear correlation with beta-prime (solar elevation) angle, peaking in mid-August 1998 when the beta-prime angle reached -80 to -90 degrees. In this paper we discuss the tuning of the non-conservative force model, for GFO and report the subsequent addition of the GFO tracking data to the Earth gravity model solutions.

Preliminary Results of the GPS Flight Experiment on the High Earth Orbit AMSAT-OSCAR 40 Spacecraft

NASA Technical Reports Server (NTRS)

Moreau, Michael C.; Bauer, Frank H.; Carpenter, J. Russell; Davis, Edward P.; Davis, George W.; Jackson, Larry A.

2002-01-01

The GPS flight experiment on the High Earth Orbit (HEO) AMSAT-OSCAR 40 (AO-40) spacecraft was activated for a period of approximately six weeks between 25 September and 2 November, 2001, and the initial results have exciting implications for using GPS as a low-cost orbit determination sensor for future HEO missions. AO-40, an amateur radio satellite launched November 16, 2000, is currently in a low inclination, 1000 by 58,800 km altitude orbit. Although the GPS receiver was not initialized in any way, it regularly returned GPS observations from points all around the orbit. Raw signal to noise levels as high as 9 AMUs (Trimble Amplitude Measurement Units) or approximately 48 dB-Hz have been recorded at apogee, when the spacecraft was close to 60,000 km in altitude. On several occasions when the receiver was below the GPS constellation (below 20,000 krn altitude), observations were reported for GPS satellites tracked through side lobe transmissions. Although the receiver has not returned any point solutions, there has been at least one occasion when four satellites were tracked simultaneously, and this short arc of data was used to compute point solutions after the fact. These results are encouraging, especially considering the spacecraft is currently in a spin-stabilized attitude mode that narrows the effective field of view of the receiving antennas and adversely affects GPS tracking. Already AO-40 has demonstrated the feasibility of recording GPS observations in HEO using an unaided receiver. Furthermore, it is providing important information about the characteristics of GPS signals received by a spacecraft in a HEO, which has long been of interest to many in the GPS community. Based on the data returned so far, the tracking performance is expected to improve when the spacecraft is transitioned to a three axis stabilized, nadir pointing attitude in Summer, 2002.

Estimating the k2 Tidal Gravity Love Number of Mars

NASA Technical Reports Server (NTRS)

Smith, David E.; Zuber, Maria; Torrence, Mark; Dunn, Peter

2003-01-01

Analysis of the orbits of spacecraft can be used to infer global tidal parameters. For Mars, the Mars Global Surveyor (MGS) spacecraft has been used to estimate the second degree Love number, k2 from the tracking DSN tracking Doppler and range data by several authors. Unfortunately, neither of the spacecraft presently in orbit are ideally suited to tidal recovery because they are in sun-synchronous orbits that vary only slightly in local time; and, further, the sub-solar location only varies by about 25 degrees in latitude. Never-the less respectable estimates of the k2 tide have been made by several authors. We present an updated solution of the degree 2 zonal Love number, compare with previous dues, and analyze the sensitivity of the solution to orbital parameters, spacecraft maneuvers, and solution methodology. Estimating the k2 Tidal Gravity Love Number of Mars.

TDRS-L spacecraft lift to mate on Atlas V

NASA Image and Video Library

2014-01-13

CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station's Vertical Integration Facility at Launch Complex 41, NASA's Tracking and Data Relay Satellite, or TDRS-L, spacecraft is lifted for mounting atop a United Launch Alliance Atlas V rocket. The TDRS-L satellite will be a part of the second of three next-generation spacecraft designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop a United Launch Alliance Atlas V rocket on Jan. 23, 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. For more information, visit: http://www.nasa.gov/mission_pages/tdrs/home/index.html Photo credit: NASA/Dimitri Gerondidakis

TDRS-L spacecraft lift to mate on Atlas V

NASA Image and Video Library

2014-01-13

CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station's Vertical Integration Facility at Launch Complex 41, NASA's Tracking and Data Relay Satellite, or TDRS-L, spacecraft is moved into position for mating atop a United Launch Alliance Atlas V rocket. The TDRS-L satellite will be a part of the second of three next-generation spacecraft designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop a United Launch Alliance Atlas V rocket on Jan. 23, 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. For more information, visit: http://www.nasa.gov/mission_pages/tdrs/home/index.html Photo credit: NASA/Dimitri Gerondidakis

TDRS-L Spacecraft Fairing Encapsulation

NASA Image and Video Library

2014-01-08

TITUSVILLE, Fla. – Inside the Astrotech payload processing facility in Titusville, United Launch Alliance engineers and technicians encapsulate the Tracking and Data Relay Satellite, or TDRS-L, spacecraft in its payload fairing. TDRS-L will then be transported to Launch Complex 41 at Cape Canaveral Air Force Station. The TDRS-L satellite will be a part of the second of three next-generation spacecraft designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop a United Launch Alliance Atlas V rocket on January 23, 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. For more information, visit: http://www.nasa.gov/mission_pages/tdrs/home/index.html

TDRS-L Spacecraft Fairing Encapsulation

NASA Image and Video Library

2014-01-08

TITUSVILLE, Fla. – Inside the Astrotech payload processing facility in Titusville NASA's Tracking and Data Relay Satellite, or TDRS-L, spacecraft is being encapsulated in its payload fairing prior to being transported to Launch Complex 41 at Cape Canaveral Air Force Station. The TDRS-L satellite will be a part of the second of three next-generation spacecraft designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop a United Launch Alliance Atlas V rocket on January 23, 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. For more information, visit: http://www.nasa.gov/mission_pages/tdrs/home/index.html

TDRS-L Spacecraft Fairing Encapsulation

NASA Image and Video Library

2014-01-08

TITUSVILLE, Fla. – Inside the Astrotech payload processing facility in Titusville, the Tracking and Data Relay Satellite, or TDRS-L, spacecraft is being encapsulated in its payload fairing in preparation for begin transported to Launch Complex 41 at Cape Canaveral Air Force Station. The TDRS-L satellite will be a part of the second of three next-generation spacecraft designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop a United Launch Alliance Atlas V rocket on January 23, 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. For more information, visit: http://www.nasa.gov/mission_pages/tdrs/home/index.html

TDRS-L Spacecraft Fairing Encapsulation

NASA Image and Video Library

2014-01-08

TITUSVILLE, Fla. – Inside the Astrotech payload processing facility in Titusville, NASA's Tracking and Data Relay Satellite, or TDRS-L, spacecraft has been encapsulated in its payload fairing. TDRS-L will then be transported to Launch Complex 41 at Cape Canaveral Air Force Station. The TDRS-L satellite will be a part of the second of three next-generation spacecraft designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop a United Launch Alliance Atlas V rocket on January 23, 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. For more information, visit: http://www.nasa.gov/mission_pages/tdrs/home/index.html

TDRS-L Spacecraft is Lifted Onto Transporter

NASA Image and Video Library

2014-01-10

TITUSVILLE, Fla. – Encapsulated in its payload fairing, NASA's Tracking and Data Relay Satellite, or TDRS-L, spacecraft is being mounted on a transporter for its trip from the Astrotech payload processing facility in Titusville to Launch Complex 41 at Cape Canaveral Air Force Station. The TDRS-L satellite will be a part of the second of three next-generation spacecraft designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop a United Launch Alliance Atlas V rocket on January 23, 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. For more information, visit: http://www.nasa.gov/mission_pages/tdrs/home/index.html Photo credit: NASA/Kim Shiflett

TDRS-L Spacecraft Transported from Astrotech to SLC

NASA Image and Video Library

2014-01-13

TITUSVILLE, Fla. – Encapsulated in its payload fairing, NASA's Tracking and Data Relay Satellite, or TDRS-L, spacecraft begins it trip from the Astrotech payload processing facility in Titusville to Launch Complex 41 at Cape Canaveral Air Force Station. The TDRS-L satellite will be a part of the second of three next-generation spacecraft designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop a United Launch Alliance Atlas V rocket on January 23, 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. For more information, visit: http://www.nasa.gov/mission_pages/tdrs/home/index.html Photo credit: NASA/Dimitri Gerondidakis

TDRS-L Spacecraft Fairing Encapsulation

NASA Image and Video Library

2014-01-08

TITUSVILLE, Fla. – Inside the Astrotech payload processing facility in Titusville, United Launch Alliance engineers and technicians ensure precision as the Tracking and Data Relay Satellite, or TDRS-L, spacecraft is being encapsulated in its payload fairing in preparation for begin transported to Launch Complex 41 at Cape Canaveral Air Force Station. The TDRS-L satellite will be a part of the second of three next-generation spacecraft designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop a United Launch Alliance Atlas V rocket on January 23, 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. For more information, visit: http://www.nasa.gov/mission_pages/tdrs/home/index.html

TDRS-L Spacecraft Transported from Astrotech to SLC

NASA Image and Video Library

2014-01-13

CAPE CANAVERAL, Fla. – Encapsulated in its payload fairing, NASA's Tracking and Data Relay Satellite, or TDRS-L, spacecraft arrives at Cape Canaveral Air Force Station's Vertical Integration Facility at Launch Complex 41. The TDRS-L satellite will be a part of the second of three next-generation spacecraft designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop a United Launch Alliance Atlas V rocket on January 23, 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. For more information, visit: http://www.nasa.gov/mission_pages/tdrs/home/index.html Photo credit: NASA/Dimitri Gerondidakis

TDRS-L spacecraft lift to mate on Atlas V

NASA Image and Video Library

2014-01-13

CAPE CANAVERAL, Fla. – At Cape Canaveral Air Force Station's Vertical Integration Facility at Launch Complex 41, NASA's Tracking and Data Relay Satellite, or TDRS-L, spacecraft has been mated atop a United Launch Alliance Atlas V rocket. The TDRS-L satellite will be a part of the second of three next-generation spacecraft designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop a United Launch Alliance Atlas V rocket on Jan. 23, 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. For more information, visit: http://www.nasa.gov/mission_pages/tdrs/home/index.html Photo credit: NASA/Dimitri Gerondidakis

TDRS-L Spacecraft is Lifted Onto Transporter

NASA Image and Video Library

2014-01-10

TITUSVILLE, Fla. – Inside the Astrotech payload processing facility in Titusville, NASA's Tracking and Data Relay Satellite, or TDRS-L, spacecraft has been encapsulated in its payload fairing in preparation for begin transported to Launch Complex 41 at Cape Canaveral Air Force Station. The TDRS-L satellite will be a part of the second of three next-generation spacecraft designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop a United Launch Alliance Atlas V rocket on January 23, 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. For more information, visit: http://www.nasa.gov/mission_pages/tdrs/home/index.html Photo credit: NASA/Kim Shiflett

TDRS-L Spacecraft Fairing Encapsulation

NASA Image and Video Library

2014-01-08

TITUSVILLE, Fla. – Inside the Astrotech payload processing facility in Titusville, the Tracking and Data Relay Satellite, or TDRS-L, spacecraft is being encapsulated in its payload fairing in preparation for being transported to Launch Complex 41 at Cape Canaveral Air Force Station. The TDRS-L satellite will be a part of the second of three next-generation spacecraft designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop a United Launch Alliance Atlas V rocket on January 23, 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. For more information, visit: http://www.nasa.gov/mission_pages/tdrs/home/index.html

TDRS-L Spacecraft Transported from Astrotech to SLC

NASA Image and Video Library

2014-01-13

CAPE CANAVERAL, Fla. – Encapsulated in its payload fairing, NASA's Tracking and Data Relay Satellite, or TDRS-L, spacecraft is transported along the Saturn Causeway at the Kennedy Space Center on its way to Launch Complex 41 at Cape Canaveral Air Force Station. The TDRS-L satellite will be a part of the second of three next-generation spacecraft designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop a United Launch Alliance Atlas V rocket on January 23, 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. For more information, visit: http://www.nasa.gov/mission_pages/tdrs/home/index.html Photo credit: NASA/Dimitri Gerondidakis

TDRS-L Spacecraft Fairing Encapsulation

NASA Image and Video Library

2014-01-08

TITUSVILLE, Fla. – Inside the Astrotech payload processing facility in Titusville, NASA's Tracking and Data Relay Satellite, or TDRS-L, spacecraft is being encapsulated in its payload fairing in preparation for begin transported to Launch Complex 41 at Cape Canaveral Air Force Station. The TDRS-L satellite will be a part of the second of three next-generation spacecraft designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop a United Launch Alliance Atlas V rocket on January 23, 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. For more information, visit: http://www.nasa.gov/mission_pages/tdrs/home/index.html

TDRS-L spacecraft lift to mate on Atlas V

NASA Image and Video Library

2014-01-13

CAPE CANAVERAL, Fla. – Encapsulated in its payload fairing, NASA's Tracking and Data Relay Satellite, or TDRS-L, spacecraft arrives at Cape Canaveral Air Force Station's Vertical Integration Facility at Launch Complex 41. The TDRS-L satellite will be a part of the second of three next-generation spacecraft designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop a United Launch Alliance Atlas V rocket on Jan. 23, 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. For more information, visit: http://www.nasa.gov/mission_pages/tdrs/home/index.html Photo credit: NASA/Dimitri Gerondidakis

Dual-quaternion based fault-tolerant control for spacecraft formation flying with finite-time convergence.

PubMed

Dong, Hongyang; Hu, Qinglei; Ma, Guangfu

2016-03-01

Study results of developing control system for spacecraft formation proximity operations between a target and a chaser are presented. In particular, a coupled model using dual quaternion is employed to describe the proximity problem of spacecraft formation, and a nonlinear adaptive fault-tolerant feedback control law is developed to enable the chaser spacecraft to track the position and attitude of the target even though its actuator occurs fault. Multiple-task capability of the proposed control system is further demonstrated in the presence of disturbances and parametric uncertainties as well. In addition, the practical finite-time stability feature of the closed-loop system is guaranteed theoretically under the designed control law. Numerical simulation of the proposed method is presented to demonstrate the advantages with respect to interference suppression, fast tracking, fault tolerant and practical finite-time stability. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

Telecommunications Relay Support of the Mars Phoenix Lander Mission

NASA Technical Reports Server (NTRS)

Edwards, Charles D., Jr.; Erickson, James K.; Gladden, Roy E.; Guinn, Joseph R.; Ilott, Peter A.; Jai, Benhan; Johnston, Martin D.; Kornfeld, Richard P.; Martin-Mur, Tomas J.; McSmith, Gaylon W.;

Man-made space debris - Does it restrict free access to space

NASA Technical Reports Server (NTRS)

Wolfe, M.; Chobotov, V.; Kessler, D.; Reynolds, R.

1981-01-01

Consideration is given to the hazards posed by existing and future man-made space debris to spacecraft operations. The components of the hazard are identified as those fragments resulting from spacecraft explosions and spent stages which can be tracked, those fragments which are too small to be tracked at their present distances, and future debris, which, if present trends in spacecraft design and operation continue, may lead to an unacceptably high probability of collision with operational spacecraft within a decade. It is argued that a coordinated effort must be undertaken by all space users to evaluate means of space debris control in order to allow for the future unrestricted use of near-earth space. A plan for immediate action to forestall the space debris problem by activities in the areas of education, debris monitoring and collection technology, space vehicle design, space operational procedures and practices and space policies and treaties is proposed.

Preliminary Investigations of an Optical Assembly Tracking Mechanism for LISA

NASA Technical Reports Server (NTRS)

Thorpe, James Ira; Stebbins, Robin

2010-01-01

After injection into their specific orbits, the position of the LISA spacecraft are not actively controlled. Rather the spacecraft are allowed to passively follow their trajectories and the roughly equilateral triangular constellation is preserved. Slight variations in the orbits cause the constellation to experience both periodic and secular variations, one consequence of which is a variation in the interior angles of the constellation on the order of one degree. This variation is larger than the field of view of the LISA telescope, requiring a mechanism for each spacecraft to maintain pointing to its two companions. This Optical Assembly Tracking Mechanism (OATM) will be used to accommodate these variations while maintaining pointing at the ten nanoradian level to the far spacecraft. Here we report on a possible design for the OATM as well as initial results from a test campaign of a piezo-inchworm actuator used to drive the mechanism.

KSC-02pd1574

NASA Image and Video Library

2002-10-18

KENNEDY SPACE CENTER, FLA. - A crane is lifted from the SLF to attach to the container with the TDRS-J spacecraft inside (at left). The container will be placed on a transporter and taken to the Spacecraft Assembly and Encapsulation Facility-2 (SAEF-2). TDRS-J is the third in the current series of three Tracking and Data Relay Satellites designed to replenish the existing on-orbit fleet of six spacecraft, the first of which was launched in 1983. The Tracking and Data Relay Satellite System is the primary source of space-to-ground voice, data and telemetry for the Space Shuttle. It also provides communications with the International Space Station and scientific spacecraft in low-earth orbit such as the Hubble Space Telescope, and launch support for some expendable vehicles. This new advanced series of satellites will extend the availability of TDRS communications services until approximately 2017.

Spacecraft navigation at Mars using earth-based and in situ radio tracking techniques

NASA Astrophysics Data System (ADS)

Thurman, S. W.; Edwards, C. D.; Kahn, R. D.; Vijayaraghavan, A.; Hastrup, R. C.; Cesarone, R. J.

1992-08-01

A survey of earth-based and in situ radiometric data types and results from a number of studies investigating potential radio navigation performance for spacecraft approaching/orbiting Mars and for landed spacecraft and rovers on the surface of Mars are presented. The performance of Doppler, ranging and interferometry earth-based data types involving single or multiple spacecraft is addressed. This evaluation is conducted with that of in situ data types, such as Doppler and ranging measurements between two spacecraft near Mars, or between a spacecraft and one or more surface radio beacons.

Spacecraft navigation at Mars using earth-based and in situ radio tracking techniques

NASA Technical Reports Server (NTRS)

Thurman, S. W.; Edwards, C. D.; Kahn, R. D.; Vijayaraghavan, A.; Hastrup, R. C.; Cesarone, R. J.

1992-01-01

A survey of earth-based and in situ radiometric data types and results from a number of studies investigating potential radio navigation performance for spacecraft approaching/orbiting Mars and for landed spacecraft and rovers on the surface of Mars are presented. The performance of Doppler, ranging and interferometry earth-based data types involving single or multiple spacecraft is addressed. This evaluation is conducted with that of in situ data types, such as Doppler and ranging measurements between two spacecraft near Mars, or between a spacecraft and one or more surface radio beacons.

Orbit Determination of Spacecraft in Earth-Moon L1 and L2 Libration Point Orbits

NASA Technical Reports Server (NTRS)

Woodard, Mark; Cosgrove, Daniel; Morinelli, Patrick; Marchese, Jeff; Owens, Brandon; Folta, David

2011-01-01

The ARTEMIS mission, part of the THEMIS extended mission, is the first to fly spacecraft in the Earth-Moon Lissajous regions. In 2009, two of the five THEMIS spacecraft were redeployed from Earth-centered orbits to arrive in Earth-Moon Lissajous orbits in late 2010. Starting in August 2010, the ARTEMIS P1 spacecraft executed numerous stationkeeping maneuvers, initially maintaining a lunar L2 Lissajous orbit before transitioning into a lunar L1 orbit. The ARTEMIS P2 spacecraft entered a L1 Lissajous orbit in October 2010. In April 2011, both ARTEMIS spacecraft will suspend Lissajous stationkeeping and will be maneuvered into lunar orbits. The success of the ARTEMIS mission has allowed the science team to gather unprecedented magnetospheric measurements in the lunar Lissajous regions. In order to effectively perform lunar Lissajous stationkeeping maneuvers, the ARTEMIS operations team has provided orbit determination solutions with typical accuracies on the order of 0.1 km in position and 0.1 cm/s in velocity. The ARTEMIS team utilizes the Goddard Trajectory Determination System (GTDS), using a batch least squares method, to process range and Doppler tracking measurements from the NASA Deep Space Network (DSN), Berkeley Ground Station (BGS), Merritt Island (MILA) station, and United Space Network (USN). The team has also investigated processing of the same tracking data measurements using the Orbit Determination Tool Kit (ODTK) software, which uses an extended Kalman filter and recursive smoother to estimate the orbit. The orbit determination results from each of these methods will be presented and we will discuss the advantages and disadvantages associated with using each method in the lunar Lissajous regions. Orbit determination accuracy is dependent on both the quality and quantity of tracking measurements, fidelity of the orbit force models, and the estimation techniques used. Prior to Lissajous operations, the team determined the appropriate quantity of tracking measurements that would be needed to meet the required orbit determination accuracies. Analysts used the Orbit Determination Error Analysis System (ODEAS) to perform covariance analyses using various tracking data schedules. From this analysis, it was determined that 3.5 hours of DSN TRK-2-34 range and Doppler tracking data every other day would suffice to meet the predictive orbit knowledge accuracies in the Lissajous region. The results of this analysis are presented. Both GTDS and ODTK have high-fidelity environmental orbit force models that allow for very accurate orbit estimation in the lunar Lissajous regime. These models include solar radiation pressure, Earth and Moon gravity models, third body gravitational effects from the Sun, and to a lesser extent third body gravitational effects from Jupiter, Venus, Saturn, and Mars. Increased position and velocity uncertainties following each maneuver, due to small execution performance errors, requires that several days of post-maneuver tracking data be processed to converge on an accurate post-maneuver orbit solution. The effects of maneuvers on orbit determination accuracy will be presented, including a comparison of the batch least squares technique to the extended Kalman filter/smoother technique. We will present the maneuver calibration results derived from processing post-maneuver tracking data. A dominant error in the orbit estimation process is the uncertainty in solar radiation pressure and the resultant force on the spacecraft. An estimation of this value can include many related factors, such as the uncertainty in spacecraft reflectivity and surface area which is a function of spacecraft orientation (spin-axis attitude), uncertainty in spacecraft wet mass, and potential seasonal variability due to the changing direction of the Sun line relative to the Earth-Moon Lissajous reference frame. In addition, each spacecraft occasionally enters into Earth or Moon penumbra or umbra and these shadow crossings reduche solar radiation force for several hours. The effects of these events on orbit determination accuracy will be presented. In order to plan for upcoming stationkeeping maneuvers, the maneuver planning team must take the current orbit estimate, propagate it forward to the planned maneuver time, and determine the optimal maneuver to maintain the Lissajous orbit for one or more revolutions. The propagation is performed using a Runge-Kutta 7/8 integrator and typically the position and velocity uncertainty increases with propagation time, increasing the overall uncertainty of the orbit state at the maneuver execution time. The effect of orbit knowledge uncertainty on stationkeeping operations will be presented.

Discovery of Non-random Spatial Distribution of Impacts in the Stardust Cometary Collector

NASA Technical Reports Server (NTRS)

Horz, Friedrich; Westphal, Andrew J.; Gainsforth, Zack; Borg, Janet; Djouadi, Zahia; Bridges, John; Franchi, Ian; Brownlee, Donald E.; Cheng. Andrew F.; Clark, Benton C.;

KSC-2009-5050

NASA Image and Video Library

2009-08-20

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., workers observe as the SV1-SV2 spacecraft is lifted for weighing. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5048

NASA Image and Video Library

2009-08-20

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., the SV1-SV2 spacecraft is ready to be weighed. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5049

NASA Image and Video Library

2009-08-20

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., workers observe as the SV1-SV2 spacecraft is lifted for weighing. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5021

NASA Image and Video Library

2009-08-03

CAPE CANAVERAL, Fla. –At the Astrotech payload processing facility in Titusville, Fla., the SV1 spacecraft is lowered onto the SV2 for mating. The two spacecraft are part of the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, Program. The STSS Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5023

NASA Image and Video Library

2009-08-03

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., the SV1 spacecraft is lowered onto the SV2 for mating. The two spacecraft are part of the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, Program. The STSS Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5053

NASA Image and Video Library

2009-08-20

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., the SV1-SV2 spacecraft sits on the rotation stand after weighing. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5042

NASA Image and Video Library

2009-08-20

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., workers begin center of gravity testing, weighing and balancing on the SV1-SV2 spacecraft. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5020

NASA Image and Video Library

2009-08-03

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., the SV1 spacecraft is lowered toward the SV2 for mating. The two spacecraft are part of the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, Program. The STSS Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5025

NASA Image and Video Library

2009-08-03

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., workers check the mating of the SV1 spacecraft onto the SV2. The two spacecraft are part of the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, Program. The STSS Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5051

NASA Image and Video Library

2009-08-20

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., the SV1-SV2 spacecraft is lifted for weighing. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5013

NASA Image and Video Library

2009-08-03

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., workers prepare to lift the SV1 and mate it to the SV2 spacecraft for the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, Program. STSS-Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. The spacecraft is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

Control of nonlinear systems with applications to constrained robots and spacecraft attitude stabilization

NASA Technical Reports Server (NTRS)

Krishnan, Hariharan

1993-01-01

This thesis is organized in two parts. In Part 1, control systems described by a class of nonlinear differential and algebraic equations are introduced. A procedure for local stabilization based on a local state realization is developed. An alternative approach to local stabilization is developed based on a classical linearization of the nonlinear differential-algebraic equations. A theoretical framework is established for solving a tracking problem associated with the differential-algebraic system. First, a simple procedure is developed for the design of a feedback control law which ensures, at least locally, that the tracking error in the closed loop system lies within any given bound if the reference inputs are sufficiently slowly varying. Next, by imposing additional assumptions, a procedure is developed for the design of a feedback control law which ensures that the tracking error in the closed loop system approaches zero exponentially for reference inputs which are not necessarily slowly varying. The control design methodologies are used for simultaneous force and position control in constrained robot systems. The differential-algebraic equations are shown to characterize the slow dynamics of a certain nonlinear control system in nonstandard singularly perturbed form. In Part 2, the attitude stabilization (reorientation) of a rigid spacecraft using only two control torques is considered. First, the case of momentum wheel actuators is considered. The complete spacecraft dynamics are not controllable. However, the spacecraft dynamics are small time locally controllable in a reduced sense. The reduced spacecraft dynamics cannot be asymptotically stabilized using continuous feedback, but a discontinuous feedback control strategy is constructed. Next, the case of gas jet actuators is considered. If the uncontrolled principal axis is not an axis of symmetry, the complete spacecraft dynamics are small time locally controllable. However, the spacecraft attitude cannot be asymptotically stabilized using continuous feedback, but a discontinuous stabilizing feedback control strategy is constructed. If the uncontrolled principal axis is an axis of symmetry, the complete spacecraft dynamics cannot be stabilized. However, the spacecraft dynamics are small time locally controllable in a reduced sense. The reduced spacecraft dynamics cannot be asymptotically stabilized using continuous feedback, but again a discontinuous feedback control strategy is constructed.

Optimal reorientation of asymmetric underactuated spacecraft using differential flatness and receding horizon control

NASA Astrophysics Data System (ADS)

Cai, Wei-wei; Yang, Le-ping; Zhu, Yan-wei

2015-01-01

This paper presents a novel method integrating nominal trajectory optimization and tracking for the reorientation control of an underactuated spacecraft with only two available control torque inputs. By employing a pseudo input along the uncontrolled axis, the flatness property of a general underactuated spacecraft is extended explicitly, by which the reorientation trajectory optimization problem is formulated into the flat output space with all the differential constraints eliminated. Ultimately, the flat output optimization problem is transformed into a nonlinear programming problem via the Chebyshev pseudospectral method, which is improved by the conformal map and barycentric rational interpolation techniques to overcome the side effects of the differential matrix's ill-conditions on numerical accuracy. Treating the trajectory tracking control as a state regulation problem, we develop a robust closed-loop tracking control law using the receding-horizon control method, and compute the feedback control at each control cycle rapidly via the differential transformation method. Numerical simulation results show that the proposed control scheme is feasible and effective for the reorientation maneuver.

Tracks of a Giant

NASA Image and Video Library

2010-08-25

The giant, 70-meter-wide antenna at NASA Deep Space Network complex in Goldstone, Calif., tracks a spacecraft on Nov. 17, 2009. This antenna, officially known as Deep Space Station 14, is also nicknamed the Mars antenna.

Hurricane Rita TrackRadar Image with Topographic Overlay

NASA Image and Video Library

2005-09-22

The Gulf Coast from the Mississippi Delta through the Texas coast is shown in this satellite image from NASA Terra spacecraft, and the predicted storm track for Hurricane Rita acquired in February, 2000.

Magnetic levitation and its application for education devices based on YBCO bulk superconductors

NASA Astrophysics Data System (ADS)

Yang, W. M.; Chao, X. X.; Guo, F. X.; Li, J. W.; Chen, S. L.

2013-10-01

A small superconducting maglev propeller system, a small spacecraft model suspending and moving around a terrestrial globe, several small maglev vehicle models and a magnetic circuit converter have been designed and constructed. The track was paved by NdFeB magnets, the arrangement of the magnets made us easy to get a uniform distribution of magnetic field along the length direction of the track and a high magnetic field gradient in the lateral direction. When the YBCO bulks mounted inside the vehicle models or spacecraft model was field cooled to LN2 temperature at a certain distance away from the track, they could be automatically floating over and moving along the track without any obvious friction. The models can be used as experimental or demonstration devices for the magnetic levitation applications.

2011 Mars Science Laboratory Trajectory Reconstruction and Performance from Launch Through Landing

NASA Technical Reports Server (NTRS)

Abilleira, Fernando

2013-01-01

The Mars Science Laboratory (MSL) mission successfully launched on an Atlas V 541 Expendable Evolved Launch Vehicle (EELV) from the Eastern Test Range (ETR) at Cape Canaveral Air Force Station (CCAFS) in Florida at 15:02:00 UTC on November 26th, 2011. At 15:52:06 UTC, six minutes after the MSL spacecraft separated from the Centaur upper stage, the spacecraft transmitter was turned on and in less than 20 s spacecraft carrier lock was achieved at the Universal Space Network (USN) Dongara tracking station located in Western Australia. MSL, carrying the most sophisticated rover ever sent to Mars, entered the Martian atmosphere at 05:10:46 SpaceCraft Event Time (SCET) UTC, and landed inside Gale Crater at 05:17:57 SCET UTC on August 6th, 2012. Confirmation of nominal landing was received at the Deep Space Network (DSN) Canberra tracking station via the Mars Odyssey relay spacecraft at 05:31:45 Earth Received Time (ERT) UTC. This paper summarizes in detail the actual vs. predicted trajectory performance in terms of launch vehicle events, launch vehicle injection performance, actual DSN/USN spacecraft lockup, trajectory correction maneuver performance, Entry, Descent, and Landing events, and overall trajectory and geometry characteristics.

Progress of Hawaii Lava Flow Tracked by NASA Spacecraft

NASA Image and Video Library

2014-09-24

On June 27, 2014, a new vent opened on Hawaii Puu Oo vent, on the eastern flank of Kilauea volcano. NASA Terra spacecraft shows the hot lava flow in white, extending about 11 miles 17 kilometers from the vent.

KSC-2009-5237

NASA Image and Video Library

2009-09-25

CAPE CANAVERAL, Fla. – Public Affairs Officer Tracy Young moderates a post-launch news conference for the media about the Space Tracking and Satellite System – Demonstrator spacecraft. Seated at center is Omar Baez, NASA launch manager, and Rear Adm. Joseph Horn, deputy director, with the U.S. Missile Defense Agency. The STSS-Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. The spacecraft was launched by NASA for the U.S. Missile Defense Agency. Photo credit: NASA/Jim Grossmann

KSC-2009-3665

NASA Image and Video Library

2009-05-01

CAPE CANAVERAL, Fla. – At NASA Kennedy Space Center's Shuttle Landing Facility, the shipping container with the STSS Demonstrator SV-2spacecraft is secured on a trailer for transfer to the Astrotech payload processing facility in Titusville, Fla. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Jack Pfaller (Approved for Public Release 09-MDA-4616 [27 May 09])

KSC-2009-3664

NASA Image and Video Library

2009-05-01

CAPE CANAVERAL, Fla. – At NASA Kennedy Space Center's Shuttle Landing Facility, the shipping container with the STSS Demonstrator SV-2spacecraft is secured on a trailer for transfer to the Astrotech payload processing facility in Titusville, Fla. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Jack Pfaller (Approved for Public Release 09-MDA-4616 [27 May 09])

KSC-2009-4629

NASA Image and Video Library

2009-07-23

CAPE CANAVERAL, Fla. – In the Astrotech payload processing facility in Titusville, Fla. , technicians check equipment on the STSS Demonstrator SV-1 spacecraft after it was lowered onto the orbital insertion system. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Tim Jacobs (Approved for Public Release 09-MDA-4800 [30 July 09] )

KSC-2009-4614

NASA Image and Video Library

2009-06-25

CAPE CANAVERAL, Fla. – At NASA Kennedy Space Center's Shuttle Landing Facility, the SV-1 cargo of the STSS Demonstrator spacecraft is moved onto a flatbed truck for transfer to the Astrotech payload processing facility in Titusville, Fla. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Kim Shiflett (Approved for Public Release 09-MDA-4804 [4 Aug 09] )

KSC-2009-4615

NASA Image and Video Library

2009-06-25

CAPE CANAVERAL, Fla. – At NASA Kennedy Space Center's Shuttle Landing Facility, the flatbed truck with the SV-1 cargo of the STSS Demonstrator spacecraft begins moving to the Astrotech payload processing facility in Titusville, Fla. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Kim Shiflett (Approved for Public Release 09-MDA-4804 [4 Aug 09] )

Tracking and data system support for the Pioneer project. Volume 2: Pioneer 11 prelaunch planning through second trajectory correction, to 1 May 1973

NASA Technical Reports Server (NTRS)

Barton, W. R.; Miller, R. B.

1975-01-01

The tracking and data system support of the planning, testing, launch, near-earth, and deep space phases of the Pioneer 11 Jupiter Mission are described, including critical phases of spacecraft flight and guidance. Scientific instruments aboard the spacecraft registered information relative to interplanetary particles and fields. Knowledge of the celestial mechanics of the solar system was improved through radiometric data gathering. Network performance, details of network support activity, and special support activities are discussed.

TDRS-L Pre-Launch Press Conference

NASA Image and Video Library

2014-01-21

CAPE CANAVERAL, Fla. – During a news conference at NASA's Kennedy Space Center in Florida, agency and contractor officials discussed preparations for the launch of NASA's Tracking and Data Relay Satellite, or TDRS-L, spacecraft. Participants included Clay Flinn, launch weather officer for the 45th Weather Squadron at Cape Canaveral Air Force Station, Fla. Seated behind Flinn is Andy Kopito, Civil Space Programs director for Boeing Space & Intelligence Systems in El Segundo, Calif. The TDRS-L spacecraft is the second of three new satellites designed to ensure vital operational continuity for NASA by expanding the lifespan of the Tracking and Data Relay Satellite System TDRSS fleet, which consists of eight satellites in geosynchronous orbit. The spacecraft provide tracking, telemetry, command and high bandwidth data return services for numerous science and human exploration missions orbiting Earth. These include NASA's Hubble Space Telescope and the International Space Station. TDRS-L has a high-performance solar panel designed for more spacecraft power to meet the growing S-band communications requirements. TDRSS is one of NASA Space Communication and Navigation’s SCaN three networks providing space communications to NASA’s missions. For more information more about TDRS-L, visit: http://www.nasa.gov/tdrs To learn more about SCaN, visit: www.nasa.gov/scan Photo credit: NASA/Frankie Martin

KSC-2009-5032

NASA Image and Video Library

2009-08-19

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., workers remove a cover from around the mated SV1 and SV2 spacecraft before center of gravity testing, weighing and balancing. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5033

NASA Image and Video Library

2009-08-19

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., the mated SV1 and SV2 spacecraft are largely uncovered before center of gravity testing, weighing and balancing. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5028

NASA Image and Video Library

2009-08-19

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., workers remove covers around the mated SV1 and SV2 spacecraft before center of gravity testing, weighing and balancing. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5039

NASA Image and Video Library

2009-08-19

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., the mated SV1 and SV2 spacecraft are on a rotation stand for center of gravity testing, weighing and balancing. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5047

NASA Image and Video Library

2009-08-20

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., an overhead crane with a scale is being attached to the SV1-SV2 spacecraft, which will be weighed. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5041

NASA Image and Video Library

2009-08-19

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., workers check the SV1-SV2 spacecraft that will undergo center of gravity testing, weighing and balancing. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5030

NASA Image and Video Library

2009-08-19

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., workers remove covers around the mated SV1 and SV2 spacecraft before center of gravity testing, weighing and balancing. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5045

NASA Image and Video Library

2009-08-20

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., an overhead crane with a scale is being attached to the SV1-SV2 spacecraft, which will be weighed. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5027

NASA Image and Video Library

2009-08-19

CAPE CANAVERAL, Fla. –At the Astrotech payload processing facility in Titusville, Fla., the mated SV1 and SV2 spacecraft are being prepared for center of gravity testing, weighing and balancing. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5052

NASA Image and Video Library

2009-08-20

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., workers observe as the SV1-SV2 spacecraft is lowered again onto the rotation stand after weighing. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5017

NASA Image and Video Library

2009-08-03

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., a crane moves the SV1 spacecraft, toward the SV2 at right. The two spacecraft , which will be mated, are part of the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, Program. The STSS Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5018

NASA Image and Video Library

2009-08-03

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., workers help guide the movement of the SV1 spacecraft as it is moved toward the SV2 at right. The two spacecraft are part of the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, Program. The STSS Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5016

NASA Image and Video Library

2009-08-03

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., workers help guide the movement of the SV1 spacecraft as it is moved toward the SV2 behind it. The two spacecraft are part of the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, Program. The STSS Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5040

NASA Image and Video Library

2009-08-19

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., a canister and protective cover are being prepared for placement around the SV1-SV2 spacecraft. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5022

NASA Image and Video Library

2009-08-03

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., workers observe as the SV1 spacecraft is lowered onto the SV2 for mating. The two spacecraft are part of the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, Program. The STSS Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5024

NASA Image and Video Library

2009-08-03

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., a worker checks the mating of the SV1 spacecraft onto the SV2. The two spacecraft are part of the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, Program. The STSS Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5036

NASA Image and Video Library

2009-08-19

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., the mated SV1 and SV2 spacecraft are being prepared for center of gravity testing, weighing and balancing. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5026

NASA Image and Video Library

2009-08-19

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., the mated SV1 and SV2 spacecraft are being prepared for center of gravity testing, weighing and balancing. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5046

NASA Image and Video Library

2009-08-20

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., an overhead crane with a scale is being attached to the SV1-SV2 spacecraft, which will be weighed. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5019

NASA Image and Video Library

2009-08-03

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., workers help guide the movement of the SV1 spacecraft as it is moved toward the SV2 at right. The two spacecraft are part of the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, Program. The STSS Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5043

NASA Image and Video Library

2009-08-20

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., an overhead crane with a scale is being moved to attach to the SV1-SV2 spacecraft, which will be weighed. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5038

NASA Image and Video Library

2009-08-19

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., the mated SV1 and SV2 spacecraft are placed on a rotation stand for center of gravity testing, weighing and balancing. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5044

NASA Image and Video Library

2009-08-20

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., an overhead crane with a scale is being moved to attach to the SV1-SV2 spacecraft, which will be weighed. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5031

NASA Image and Video Library

2009-08-19

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., workers remove covers around the mated SV1 and SV2 spacecraft before center of gravity testing, weighing and balancing. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5029

NASA Image and Video Library

2009-08-19

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., workers remove covers around the mated SV1 and SV2 spacecraft before center of gravity testing, weighing and balancing. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

Finite-time control for nonlinear spacecraft attitude based on terminal sliding mode technique.

PubMed

Song, Zhankui; Li, Hongxing; Sun, Kaibiao

2014-01-01

In this paper, a fast terminal sliding mode control (FTSMC) scheme with double closed loops is proposed for the spacecraft attitude control. The FTSMC laws are included both in an inner control loop and an outer control loop. Firstly, a fast terminal sliding surface (FTSS) is constructed, which can drive the inner loop tracking-error and the outer loop tracking-error on the FTSS to converge to zero in finite time. Secondly, FTSMC strategy is designed by using Lyaponov's method for ensuring the occurrence of the sliding motion in finite time, which can hold the character of fast transient response and improve the tracking accuracy. It is proved that FTSMC can guarantee the convergence of tracking-error in both approaching and sliding mode surface. Finally, simulation results demonstrate the effectiveness of the proposed control scheme. © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

Noncoherent Tracking of a Source of a Data-Modulated Signal

NASA Technical Reports Server (NTRS)

Arndt, G. Dickey; Ngo, Phong; Chen, Henry; Phan, Chau T.; Hill, Brent; Bourgeois, Brian; Dusl, John

2003-01-01

A proposed tracking receiver system containing three suitably positioned antenna elements and special signal-processing equipment would determine the direction of incidence of a microwave signal containing spread-spectrum digital data modulation. If the system were to contain two sets of antenna elements separated by a known baseline, it could determine the location of the transmitter as the intersection of the lines of incidence on the two antennas. Such systems could be used for diverse purposes in outer space and on Earth, including tracking astronauts and small robotic spacecraft working outside a spacecraft or space station, and locating cellular telephones from which distress calls have been made. The principle of operation does not require the transmission of a special identifying or distress signal by the cellular telephone or other transmitter to be tracked; instead, the system could utilize the data signal routinely sent by the transmitter, provided that the signal had the characteristics needed for processing.

Design concepts and performance of NASA X-band transponder (DST) for deep space spacecraft applications

NASA Technical Reports Server (NTRS)

Mysoor, Narayan R.; Perret, Jonathan D.; Kermode, Arthur W.

1991-01-01

The design concepts and measured performance characteristics of an X band (7162 MHz/8415 MHz) breadboard deep space transponder (DST) for future spacecraft applications, with the first use scheduled for the Comet Rendezvous Asteroid Flyby (CRAF) and Cassini missions in 1995 and 1996, respectively. The DST consists of a double conversion, superheterodyne, automatic phase tracking receiver, and an X band (8415 MHz) exciter to drive redundant downlink power amplifiers. The receiver acquires and coherently phase tracks the modulated or unmodulated X band (7162 MHz) uplink carrier signal. The exciter phase modulates the X band (8415 MHz) downlink signal with composite telemetry and ranging signals. The receiver measured tracking threshold, automatic gain control static phase error, and phase jitter characteristics of the breadboard DST are in good agreement with the expected performance. The measured results show a receiver tracking threshold of -158 dBm and a dynamic signal range of 88 dB.

An X-band spacecraft transponder for deep space applications - Design concepts and breadboard performance

NASA Technical Reports Server (NTRS)

Mysoor, Narayan R.; Perret, Jonathan D.; Kermode, Arthur W.

1992-01-01

The design concepts and measured performance characteristics are summarized of an X band (7162 MHz/8415 MHz) breadboard deep space transponder (DSP) for future spacecraft applications, with the first use scheduled for the Comet Rendezvous Asteroid Flyby (CRAF) and Cassini missions in 1995 and 1996, respectively. The DST consists of a double conversion, superheterodyne, automatic phase tracking receiver, and an X band (8415 MHz) exciter to drive redundant downlink power amplifiers. The receiver acquires and coherently phase tracks the modulated or unmodulated X band (7162 MHz) uplink carrier signal. The exciter phase modulates the band (8415 MHz) downlink signal with composite telemetry and ranging signals. The receiver measured tracking threshold, automatic gain control, static phase error, and phase jitter characteristics of the breadboard DST are in good agreement with the expected performance. The measured results show a receiver tracking threshold of -158 dBm and a dynamic signal range of 88 dB.

A nonlinear estimator for reconstructing the angular velocity of a spacecraft without rate gyros

NASA Technical Reports Server (NTRS)

Polites, M. E.; Lightsey, W. D.

1991-01-01

A scheme for estimating the angular velocity of a spacecraft without rate gyros is presented. It is based upon a nonlinear estimator whose inputs are measured inertial vectors and their calculated time derivatives relative to vehicle axes. It works for all spacecraft attitudes and requires no knowledge of attitude. It can use measurements from a variety of onboard sensors like Sun sensors, star trackers, or magnetometers, and in concert. It can also use look angle measurements from onboard tracking antennas for tracking and data relay satellites or global positioning system satellites. In this paper, it is applied to a Sun point scheme on the Hubble Space Telescope assuming all or most of its onboard rate gyros have failed. Simulation results are presented for verification.

Optimized tracking of RF carriers with phase noise, including Pioneer 10 results

NASA Technical Reports Server (NTRS)

Vilnrotter, V. A.; Hurd, W. J.; Brown, D. H.

1987-01-01

The ability to track very weak signals from distant spacecraft is limited by the phase instabilities of the received signal and of the local oscillator employed by the receiver. These instabilities ultimately limit the minimum loop bandwidth that can be used in a phase-coherent receiver, and hence limit the ratio of received carrier power to noise spectral density which can be tracked phase coherently. A method is presented for near real time estimation of the received carrier phase and additive noise spectrum, and optimization of the phase locked loop bandwidth. The method was used with the breadboard Deep Space Network (DSN) Advanced Receiver to optimize tracking of very weak signals from the Pioneer 10 spacecraft, which is now more distant that the edge of the solar system. Tracking with bandwidths of 0.1 Hz to 1.0 Hz reduces tracking signal threshold and increases carrier loop signal to noise ratio (SNR) by 5 dB to 15 dB compared to the 3 Hz bandwidth of the receivers now used operationally in the DSN. This will enable the DSN to track Pioneer 10 until its power sources fails near the end of the century.

Long-Term Periodicity of the Mars Exospheric Density from MRO and Mars Odyssey Radio Tracking Data

NASA Astrophysics Data System (ADS)

Genova, A.; Goossens, S. J.; Lemoine, F. G.; Mazarico, E.; Smith, D. E.; Zuber, M. T.

2014-12-01

The Mars Odyssey and Mars Reconnaissance Orbiter (MRO) missions have collected more than 11 years of continuous tracking data of spacecraft in orbit around Mars. The radio science data are generally used to determine the static and seasonal gravity field of the central body. However, these two spacecraft are in different sun-synchronous orbits that cover a wide range of altitudes (250-410 km) where investigation of the atmosphere and climate of Mars so far have not been supported by in situ and remote sensing measurements. The drag perturbation acting on the probes provides indirect measurements of the Martian atmospheric density. Therefore, we focused our work on the determination of the long-term periodicity of the atmospheric constituents in the Mars exosphere with Mars Odyssey and MRO radio tracking data. We implemented the Drag Temperature Model (DTM) -Mars model into our Precise Orbit Determination (POD) program GEODYN-II to adequately reproduce variations in temperature and (partial) density along ODY and MRO trajectories. The recovery of Mars' atmospheric dynamics using Doppler tracking data requires the accurate modeling of all forces acting on the spacecraft. The main non-conservative force, apart from drag, is solar radiation pressure. Spacecraft panel reflectivities and the radiation pressure-scaling factor are not estimated, but we adjusted empirical once-per-revolution along-track periodic accelerations (cosine and sine) over each orbital arc to mitigate solar radiation pressure mismodeling. After converging the orbital data arcs, and editing out all the data during superior conjunctions, we combined the MRO and Mars Odyssey arcs in a global solution where we estimated spacecraft initial states, time-correlated drag scale factors, and annual and semi-annual variability of the major constituents in the Mars upper atmosphere. We will show that the updated DTM-Mars model provides a better prediction of the long-term variability of the dominant species, which are CO2, O, and He at the MRO and ODY orbit altitudes. The indirect measurements of atmospheric density profiles at those altitudes provide additional information to improve general circulation models, which already suitably represent lower altitudes in the atmosphere.

Thermospheric Studies with Mars Global Surveyor

NASA Technical Reports Server (NTRS)

Lemoine, F. G.; Bruinsma, S.; Chin, D. S.; Forbes, J. M.

2006-01-01

The Mars Global Surveyor spacecraft has been located in a near-circular, polar, and low-altitude mapping orbit about Mars for six years, since February 1999. The spacecraft is tracked routinely by the antennae of the Deep Space Network (DSN), using the X Band radio system of the spacecraft. These tracking data have been used for routine spacecraft navigation, and for radio science studies, such as the estimation of the static and time-varying gravity field of Mars. In this paper we describe the methodology for reduction of these data in order to estimate the Mars atmospheric density (normalized to an altitude 380 km) over half a solar cycle, where we discern the correlation of the density with the incident solar flux, and the 27-day solar rotation. The results show that the density at the MGS altitude varies from a mean of 0.7 x 10(exp -17) grams/cu cm near aphelion to a mean of 3.0 x 10(exp -17)grams/cu cm near perihelion.

Three Generations of Tracking and Data Relay Satellite (TDRS) Spacecraft

NASA Technical Reports Server (NTRS)

Zaleski, Ron

2016-01-01

The current Tracking and Data Relay Satellite configuration consists of nine in-orbit satellites (four first generation, three second generation and two third generation satellites) globally distributed in geosynchronous orbit to provide near continuous data relay service to missions like Hubble Space Telescope and the International Space Station. The 1st generation spacecraft were designed by TRW/Northrop Grumman with their launches of the five spacecraft ranging from 1983 through 1995. The 2nd and 3rd generation spacecraft were designed by Boeing with their launches ranging 2000 - 2002 and 2013 - 2017 respectively. TDRS-3 is now 27 years on orbit, continues to be a capable asset for the TDRS constellation. Lack of need for inclination control combined with large fuel reserves and redundancy on critical elements provides spacecraft that operate well past design life, all of which contributes to expanded TDRS constellation support capabilities. All spacecraft generations have issues. Significant issues will be summarized with the focus on the Boeing related problems. Degradations and failures are continually assessed and provide the foundation for yearly updates to spacecraft reliability models, constellation service projections and deorbit plans (in order to meet NASAs mandate of limiting orbital debris). Even when accounting for degradations and failures, the life expectancy for the Boeing delivered 2nd generation TDRS-8, 9 10 TDRS are anticipated to be 25+ years.

Advanced tracking systems design and analysis

NASA Technical Reports Server (NTRS)

Potash, R.; Floyd, L.; Jacobsen, A.; Cunningham, K.; Kapoor, A.; Kwadrat, C.; Radel, J.; Mccarthy, J.

1989-01-01

The results of an assessment of several types of high-accuracy tracking systems proposed to track the spacecraft in the National Aeronautics and Space Administration (NASA) Advanced Tracking and Data Relay Satellite System (ATDRSS) are summarized. Tracking systems based on the use of interferometry and ranging are investigated. For each system, the top-level system design and operations concept are provided. A comparative system assessment is presented in terms of orbit determination performance, ATDRSS impacts, life-cycle cost, and technological risk.

South Atlantic Anomaly

Atmospheric Science Data Center

2013-04-19

... This map was created by specially processing MISR "dark" data taken between 3 February and 16 February 2000, while the cover was still ... Individual orbit tracks are visible, and some tracks are missing due to data gaps, missing spacecraft navigation information, or other ...

(abstract) ARGOS: a System to Monitor Ulysses Nutation and Thruster Firings from Variations of the Spacecraft Radio Signal

NASA Technical Reports Server (NTRS)

McElrath, T. P.; Cangahuala, L. A.; Miller, K. J.; Stravert, L. R.; Garcia-Perez, Raul

1995-01-01

Ulysses is a spin-stabilized spacecraft that experienced significant nutation after its launch in October 1990. This was due to the Sun-spacecraft-Earth geometry, and a study of the phenomenon predicted that the nutation would again be a problem during 1994-95. The difficulty of obtaining nutation estimates in real time from the spacecraft telemetry forced the ESA/NASA Ulysses Team to explore alternative information sources. The work performed by the ESA Operations Team provided a model for a system that uses the radio signal strength measurements to monitor the spacecraft dynamics. These measurements (referred to as AGC) are provided once per second by the tracking stations of the DSN. The system was named ARGOS (Attitude Reckoning from Ground Observable Signals) after the ever-vigilant, hundred-eyed giant of Greek Mythology. The ARGOS design also included Doppler processing, because Doppler shifts indicate thruster firings commanded by the active nutation control carried out onboard the spacecraft. While there is some visibility into thruster activity from telemetry, careful processing of the high-sample-rate Doppler data provides an accurate means of detecting the presence and time of thruster firings. DSN Doppler measurements are available at a ten-per-second rate in the same tracking data block as the AGC data.

Radioastron flight operations

NASA Technical Reports Server (NTRS)

Altunin, V. I.; Sukhanov, K. G.; Altunin, K. R.

1993-01-01

Radioastron is a space-based very-long-baseline interferometry (VLBI) mission to be operational in the mid-90's. The spacecraft and space radio telescope (SRT) will be designed, manufactured, and launched by the Russians. The United States is constructing a DSN subnet to be used in conjunction with a Russian subnet for Radioastron SRT science data acquisition, phase link, and spacecraft and science payload health monitoring. Command and control will be performed from a Russian tracking facility. In addition to the flight element, the network of ground radio telescopes which will be performing co-observations with the space telescope are essential to the mission. Observatories in 39 locations around the world are expected to participate in the mission. Some aspects of the mission that have helped shaped the flight operations concept are: separate radio channels will be provided for spacecraft operations and for phase link and science data acquisition; 80-90 percent of the spacecraft operational time will be spent in an autonomous mode; and, mission scheduling must take into account not only spacecraft and science payload constraints, but tracking station and ground observatory availability as well. This paper will describe the flight operations system design for translating the Radioastron science program into spacecraft executed events. Planning for in-orbit checkout and contingency response will also be discussed.

Next-Generation Ground Network Architecture for Communications and Tracking of Interplanetary Smallsats

NASA Astrophysics Data System (ADS)

Cheung, K.-M.; Abraham, D.; Arroyo, B.; Basilio, E.; Babuscia, A.; Duncan, C.; Lee, D.; Oudrhiri, K.; Pham, T.; Staehle, R.; Waldherr, S.; Welz, G.; Wyatt, J.; Lanucara, M.; Malphrus, B.; Bellardo, J.; Puig-Suari, J.; Corpino, S.

2015-08-01

As small spacecraft venture out of Earth orbit, they will encounter challenges not experienced or addressed by the numerous low Earth orbit (LEO) CubeSat and smallsat missions staged to date. The LEO CubeSats typically use low-cost, proven CubeSat radios, antennas, and university ground stations with small apertures. As more ambitious yet cost-constrained space mission concepts to the Moon and beyond are being developed, CubeSats and smallsats have the potential to provide a more affordable platform for exploring deep space and performing the associated science. Some of the challenges that have, so far, slowed the proliferation of small interplanetary spacecraft are those of communications and navigation. Unlike Earth-orbiting spacecraft that navigate via government services such as North American Aerospace Defense Command's (NORAD's) tracking elements or the Global Positioning Satellite (GPS) system, interplanetary spacecraft would have to operate in a fundamentally different manner that allows the deep-space communications link to provide both command/telemetry and the radiometric data needed for navigation. Another challenge occurs when smallsat and CubeSat missions would involve multiple spacecraft that require near-simultaneous communication and/or navigation, but have a very limited number of ground antenna assets, as well as available spectrum, to support their links. To address these challenges, the Jet Propulsion Laboratory (JPL) and the Deep Space Network (DSN) it operates for NASA are pursuing the following efforts: (1) Developing a CubeSat-compatible, DSN-compatible transponder -- Iris -- which a commercial vendor can then make available as a product line. (2) Developing CubeSat-compatible high-gain antennas -- deployable reflectors, reflectarrays, and inflatable antennas. (3) Streamlining access and utilization processes for DSN and related services such as the Advanced Multi-Mission Operations System (AMMOS). (4) Developing methodologies for tracking and operating multiple spacecraft simultaneously, including spectrum coordination. (5) Coordination and collaboration with non-DSN facilities. This article further describes the communications and tracking challenges facing interplanetary smallsats and CubeSats, and the next-generation ground network architecture being evolved to mitigate those challenges.

Research and Development in Optical Communications

NASA Technical Reports Server (NTRS)

Wilson, Keith

2004-01-01

A report in the form of lecture slides summarizes the optical-communications program of NASA s Jet Propulsion Laboratory (JPL) and describes the JPL Optical Communications Telescope Laboratory (OCTL) and its role in the program. The purpose of the program is to develop equipment and techniques for laser communication between (1) ground stations and (2) spacecraft (both near Earth and in deep space) and aircraft. The OCTL is an astronomical- style telescope facility that includes a 1-m-diameter, 75.8-m-focal length telescope in an elevation/azimuth mount, plus optical and electronic subsystems for tracking spacecraft and aircraft, receiving laser signals from such moving targets, and transmitting high-power laser signals to such targets. Near-term research at the OCTL is expected to focus on mitigating the effects of atmospheric scintillation on uplinks and on beacon-assisted tracking of ground stations by stations in deep space. Near-term experiments are expected to be performed with retroreflector-equipped aircraft and Earth-orbiting spacecraft techniques to test mathematical models of propagation of laser beams, multiple-beam strategies to mitigate uplink scintillation, and pointing and tracking accuracy of the telescope.

EOS Aqua Mission Status at Earth Science Constellation MOWG Meeting @ LASP April 13, 2016

NASA Technical Reports Server (NTRS)

Guit, William J.

2016-01-01

This presentation reflects the EOS Aqua mission status, spacecraft subsystem summary, recent and planned activities, inclination adjust maneuvers, propellant usage and lifetime estimate, orbital maintenance maneuvers, conjunction assessment high interest events, ground track error, spacecraft orbital parameters trends and predictions.

Velocity-free attitude coordinated tracking control for spacecraft formation flying.

PubMed

Hu, Qinglei; Zhang, Jian; Zhang, Youmin

2018-02-01

This article investigates the velocity-free attitude coordinated tracking control scheme for a group of spacecraft with the assumption that the angular velocities of the formation members are not available in control feedback. Initially, an angular velocity observer is constructed based on each individual's attitude quarternion. Then, the distributed attitude coordinated control law is designed by using the observed states, in which adaptive control method is adopted to handle the external disturbances. Stability of the overall closed-loop system is analyzed theoretically, which shows the system trajectory converges to a small set around origin with fast convergence rate. Numerical simulations are performed to demonstrate fast convergence and improved tracking performance of the proposed control strategy. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

Global finite-time attitude consensus tracking control for a group of rigid spacecraft

NASA Astrophysics Data System (ADS)

Li, Penghua

2017-10-01

The problem of finite-time attitude consensus for multiple rigid spacecraft with a leader-follower architecture is investigated in this paper. To achieve the finite-time attitude consensus, at the first step, a distributed finite-time convergent observer is proposed for each follower to estimate the leader's attitude in a finite time. Then based on the terminal sliding mode control method, a new finite-time attitude tracking controller is designed such that the leader's attitude can be tracked in a finite time. Finally, a finite-time observer-based distributed control strategy is proposed. It is shown that the attitude consensus can be achieved in a finite time under the proposed controller. Simulation results are given to show the effectiveness of the proposed method.

KSC-2009-5035

NASA Image and Video Library

2009-08-19

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., the top of the mated SV1 and SV2 remains covered. The spacecraft are being prepared for center of gravity testing, weighing and balancing. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5014

NASA Image and Video Library

2009-08-03

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., a crane is attached to the SV1 spacecraft, part of the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, Program. The SV1 will be lifted and moved to mate with the SV2 on another stand nearby. STSS-Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. The spacecraft is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5034

NASA Image and Video Library

2009-08-19

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., the mated SV1 and SV2 spacecraft retain the covers on the top which are being removed before center of gravity testing, weighing and balancing. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

KSC-2009-5037

NASA Image and Video Library

2009-08-19

CAPE CANAVERAL, Fla. – At the Astrotech payload processing facility in Titusville, Fla., this closeup shows part of the mated SV1 and SV2 spacecraft, which is being prepared for center of gravity testing, weighing and balancing. The two spacecraft are known as the Space Tracking and Surveillance System – Demonstrators, or STSS Demo, which is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jim Grossmann

Development of realtime connected element interferometry at the Goldstone Deep Space Communications Complex

NASA Technical Reports Server (NTRS)

Edwards, C. D.

1990-01-01

Connected-element interferometry (CEI) has the potential to provide high-accuracy angular spacecraft tracking on short baselines by making use of the very precise phase delay observable. Within the Goldstone Deep Space Communications Complex (DSCC), one of three tracking complexes in the NASA Deep Space Network, baselines of up to 21 km in length are available. Analysis of data from a series of short-baseline phase-delay interferometry experiments are presented to demonstrate the potential tracking accuracy on these baselines. Repeated differential observations of pairs of angularly close extragalactic radio sources were made to simulate differential spacecraft-quasar measurements. Fiber-optic data links and a correlation processor are currently being developed and installed at Goldstone for a demonstration of real-time CEI in 1990.

Doppler search for a gravitational background radiation with two spacecraft

NASA Astrophysics Data System (ADS)

Bertotti, B.; Iess, L.

1985-11-01

The prospect of detecting a gravitational wave background by means of a simultaneous Doppler tracking of two spacecraft are discussed. It is found that the cross spectrum of the Doppler shifts of the two spacecraft is a filtered expression of the energy density spectrum of the background. The filter function, which is expressed as a series in terms of Legendre polynomials, is obtained by an integration over the rotation group, assuming the background to be isotropic. The main noise sources are examined, and the advantages of a measurement with two spacecraft are noted.

KSC-2009-5238

NASA Image and Video Library

2009-09-25

CAPE CANAVERAL, Fla. – At a post-launch news conference for the media about launch of the Space Tracking and Satellite System – Demonstrator spacecraft, NASA Launch Manager Omar Baez, at center, responds to a question. At right is Rear Adm. Joseph Horn, deputy director, with the U.S. Missile Defense Agency. At left, Public Affairs Officer Tracy Young moderates. The STSS-Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. The spacecraft was launched by NASA for the U.S. Missile Defense Agency. Photo credit: NASA/Jim Grossmann

KSC-2009-5239

NASA Image and Video Library

2009-09-25

CAPE CANAVERAL, Fla. – At a post-launch news conference for the media about launch of the Space Tracking and Satellite System – Demonstrator spacecraft, Rear Adm. Joseph Horn, deputy director with the U.S. Missile Defense Agency, answers a question. NASA Launch Manager Omar Baez is at center. At left, Public Affairs Officer Tracy Young moderates. The STSS-Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. The spacecraft was launched by NASA for the U.S. Missile Defense Agency. Photo credit: NASA/Jim Grossmann

JPL-20180522-GRACFOf-0001-Twin Spacecraft Launch to Track Earth's Water Movement

NASA Image and Video Library

2018-05-22

A U.S./German space mission to track the continuous movement of water and other changes in Earth's mass on and beneath the planet's surface successfully launched at 12:47 p.m. PDT, May 22, 2018, from the California coast. The twin spacecraft of the Gravity Recovery and Climate Experiment Follow-On (GRACE-FO), a joint NASA/German Research Centre for Geosciences (GFZ) mission, lifted off on a SpaceX Falcon 9 rocket from Space Launch Complex-4E at Vandenberg Air Force Base in California, sharing their ride into space with five Iridium NEXT communications satellites.

KSC-2009-4611

NASA Image and Video Library

2009-06-25

CAPE CANAVERAL, Fla. – The U.S. Air Force C-17 aircraft arrives at NASA Kennedy Space Center's Shuttle Landing Facility with its SV-1 cargo of the STSS Demonstrator spacecraft. The cargo will be transferred to the Astrotech payload processing facility in Titusville, Fla. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Kim Shiflett (Approved for Public Release 09-MDA-4804 [4 Aug 09] )

KSC-2009-4612

NASA Image and Video Library

2009-06-25

CAPE CANAVERAL, Fla. – At NASA Kennedy Space Center's Shuttle Landing Facility, the SV-1 cargo of the STSS Demonstrator spacecraft moves out of the U.S. Air Force C-17. The cargo will be transferred to the Astrotech payload processing facility in Titusville, Fla. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Kim Shiflett (Approved for Public Release 09-MDA-4804 [4 Aug 09] )

KSC-2009-4613

NASA Image and Video Library

2009-06-25

CAPE CANAVERAL, Fla. – At NASA Kennedy Space Center's Shuttle Landing Facility, the SV-1 cargo of the STSS Demonstrator spacecraft moves out of the U.S. Air Force C-17. The cargo will be transferred to the Astrotech payload processing facility in Titusville, Fla. The spacecraft is a midcourse tracking technology demonstrator, part of an evolving ballistic missile defense system. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency in late summer. Photo credit: NASA/Kim Shiflett (Approved for Public Release 09-MDA-4804 [4 Aug 09] )

USA Space Debris Environment, Operations, and Research Updates

NASA Technical Reports Server (NTRS)

Liou, J.-C.

2018-01-01

Space Missions in 2017 Earth Satellite Population Collision Avoidance Maneuvers Post mission Disposal of U.S.A. Spacecraft Space Situational Awareness (SSA) and the Space Debris Sensor (SDS) A total of 86 space launches placed more than 400 spacecraft into Earth orbits during 2017, following the trend of increase over the past decade NASA has established conjunction assessment processes for its human spaceflight and uncrewed spacecraft to avoid accidental collisions with objects tracked by the U.S. Space Surveillance Network - NASA also assists other U.S. government spacecraft owners with conjunction assessments and subsequent maneuvers The ISS has conducted 25 debris collision avoidance maneuvers since 1999 - None in 2016-2017, but an ISS visiting vehicle had one collision avoidance maneuver in 2017 During 2017 NASA executed or assisted in the execution of 21 collision avoidance maneuvers by uncrewed spacecraft - Four maneuvers were conducted to avoid debris from Fengyun-1C - Two maneuvers were conducted to avoid debris from the collision of Cosmos 2251 and Iridium 33 - One maneuver was conducted to avoid the ISS NASA has established conjunction assessment processes for its human spaceflight and uncrewed spacecraft to avoid accidental collisions with objects tracked by the U.S. Space Surveillance Network - NASA also assists other U.S. government spacecraft owners with conjunction assessments and subsequent maneuvers The ISS has conducted 25 debris collision avoidance maneuvers since 1999 - None in 2016-2017, but an ISS visiting vehicle had one collision avoidance maneuver in 2017 During 2017 NASA executed or assisted in the execution of 21 collision avoidance maneuvers by uncrewed spacecraft - Four maneuvers were conducted to avoid debris from Fengyun-1C - Two maneuvers were conducted to avoid debris from the collision of Cosmos 2251 and Iridium 33 The 2014-15 NASA Engineering and Safety Center (NESC) study on the micrometeoroid and orbital debris (MMOD) assessment for the Joint Polar Satellite System (JPSS) provided the following findings - Millimeter-sized orbital debris pose the highest penetration risk to most operational spacecraft in LEO - The most effective means to collect direct measurement data on millimetersized debris above 600 km altitude is to conduct in situ measurements - There is currently no in situ data on such small debris above 600 km altitude Since the orbital debris population follows a power-law size distribution, there are many more millimeter-sized debris than the large tracked objects - Current conjunction assessments and collision avoidance maneuvers against the tracked objects (which are typically 10 cm and larger) only address a small fraction (<1%) of the mission-ending risk from orbital debris To address the millimeter-sized debris data gap above 600 km, NASA has recently developed an innovative in situ measurement instrument - the Space Debris Sensor (SDS) - One maneuver was conducted to avoid the ISS

Task one report: Optical system study. [characteristics of laser equipment for space communication systems

NASA Technical Reports Server (NTRS)

1973-01-01

An optical system which can be incorporated in a present day or near future space-borne laser communications system is described. Techniques of implementing these systems are presented and their design problems and use are discussed. Optical system weight is estimated as a function of aperture diameter for a typical present day or near future laser communication system. The optical communications system considered is a two-way, high data rate optical communications link from a spacecraft to a spacecraft or from a spacecraft to a ground station. Each station has a laser transmitter and receiver and a pointing and tracking system. Thus each station can track the laser transmitter of the other. Optical beamwidths are considered to be as small as an arc-second with the beam pointed to a fraction of this beamwidth.

KSC-02pd1576

NASA Image and Video Library

2002-10-18

KENNEDY SPACE CENTER, FLA. - At the KSC Shuttle Landing Facility, an overhead crane lifts the container with the TDRS-J spacecraft onto a transport vehicle. In the background is the Air Force C-17 air cargo plane that delivered it. TDRS-J is the third in the current series of three Tracking and Data Relay Satellites designed to replenish the existing on-orbit fleet of six spacecraft, the first of which was launched in 1983. The Tracking and Data Relay Satellite System is the primary source of space-to-ground voice, data and telemetry for the Space Shuttle. It also provides communications with the International Space Station and scientific spacecraft in low-earth orbit such as the Hubble Space Telescope, and launch support for some expendable vehicles. This new advanced series of satellites will extend the availability of TDRS communications services until approximately 2017.

Use of Very Long Baseline Array Interferometric Data for Spacecraft Navigation

NASA Technical Reports Server (NTRS)

Martin-Mur, Tomas J.; Antreasian, P.; Border, J.; Benson, J.; Dhawan, V.; Fomalont, E.; Graat, E.; Jacobson, R.; Lanyi, G.; McElrath, T.;

GRACE-FO Spacecraft (Artist's Rendering)

NASA Image and Video Library

2018-04-25

Artist's rendering of the twin spacecraft of the Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) mission, scheduled to launch in May, 2018. GRACE-FO will track the evolution of Earth's water cycle by monitoring changes in the distribution of mass on Earth. https://photojournal.jpl.nasa.gov/catalog/PIA22431

Summary of spacecraft technology, systems reliability, and tracking data acquisition

NASA Technical Reports Server (NTRS)

1973-01-01

Goddard activities are reported for 1973. An eight-year flight schedule for projected space missions is presented. Data acquired by spacecraft in the following disciplines are described: stellar ultraviolet, stellar X-rays, stellar gamma rays, solar radiation, radio astronomy, particles/fields, magnetosphere, aurora, and the upper atmosphere.

Spacecraft applications of advanced global positioning system technology

NASA Technical Reports Server (NTRS)

Huth, Gaylord; Dodds, James; Udalov, Sergei; Austin, Richard; Loomis, Peter; Duboraw, I. Newton, III

1988-01-01

The purpose of this study was to evaluate potential uses of Global Positioning System (GPS) in spacecraft applications in the following areas: attitude control and tracking; structural control; traffic control; and time base definition (synchronization). Each of these functions are addressed. Also addressed are the hardware related issues concerning the application of GPS technology and comparisons are provided with alternative instrumentation methods for specific functions required for an advanced low earth orbit spacecraft.

GRAVSAT/GEOPAUSE refraction study

NASA Technical Reports Server (NTRS)

Llewellyn, S. K.

1977-01-01

A ground station network tracked a high altitude spacecraft which in turn tracked a low orbiting satellite. Orbit data are relayed back to the ground stations. A refraction study was performed on this configuration to compute ionospheric and tropospheric refraction effects along the satellite and ground links.

The Deep Space Network

NASA Technical Reports Server (NTRS)

1979-01-01

Deep Space Network progress in flight project support, tracking and data acquisition, research and technology, network engineering, hardware and software implementation, and operations is cited. Topics covered include: tracking and ground based navigation; spacecraft/ground communication; station control and operations technology; ground communications; and deep space stations.

Ulysses orbit determination at high declinations

NASA Technical Reports Server (NTRS)

Mcelrath, Timothy P.; Lewis, George D.

1995-01-01

The trajectory of the Ulysses spacecraft caused its geocentric declination to exceed 60 deg South for over two months during the Fall of 1994, permitting continuous tracking from a single site. During this time, spacecraft operations constraints allowed only Doppler tracking data to be collected, and imposed a high radial acceleration uncertainty on the orbit determination process. The unusual aspects of this situation have motivated a re-examination of the Hamilton-Melbourne results, which have been used before to estimate the information content of Doppler tracking for trajectories closer to the ecliptic. The addition of an acceleration term to this equation is found to significantly increase the declination uncertainty for symmetric passes. In addition, a simple means is described to transform the symmetric results when the tracking pass is non-symmetric. The analytical results are then compared against numerical studies of this tracking geometry and found to be in good agreement for the angular uncertainties. The results of this analysis are applicable to the Near Earth Asteroid Rendezvous (NEAR) mission and to any other missions with high declination trajectories, as well as to missions using short tracking passes and/or one-way Doppler data.

Neural network based satellite tracking for deep space applications

NASA Technical Reports Server (NTRS)

Amoozegar, F.; Ruggier, C.

2003-01-01

The objective of this paper is to provide a survey of neural network trends as applied to the tracking of spacecrafts in deep space at Ka-band under various weather conditions and examine the trade-off between tracing accuracy and communication link performance.

Study of tracking and data acquisition system for the 1990's. Volume 4: TDAS space segment architecture

NASA Technical Reports Server (NTRS)

Orr, R. S.

1984-01-01

Tracking and data acquisition system (TDAS) requirements, TDAS architectural goals, enhanced TDAS subsystems, constellation and networking options, TDAS spacecraft options, crosslink implementation, baseline TDAS space segment architecture, and treat model development/security analysis are addressed.

Design concepts and performance of NASA X-band (7162 MHz/8415 MHz) transponder for deep-space spacecraft applications

NASA Technical Reports Server (NTRS)

Mysoor, N. R.; Perret, J. D.; Kermode, A. W.

1991-01-01

The design concepts and measured performance characteristics are summarized of an X band (7162 MHz/8415 MHz) breadboard deep space transponder (DSP) for future spacecraft applications, with the first use scheduled for the Comet Rendezvous Asteroid Flyby (CRAF) and Cassini missions in 1995 and 1996, respectively. The DST consists of a double conversion, superheterodyne, automatic phase tracking receiver, and an X band (8415 MHz) exciter to drive redundant downlink power amplifiers. The receiver acquires and coherently phase tracks the modulated or unmodulated X band (7162 MHz) uplink carrier signal. The exciter phase modulates the X band (8415 MHz) downlink signal with composite telemetry and ranging signals. The receiver measured tracking threshold, automatic gain control, static phase error, and phase jitter characteristics of the breadboard DST are in good agreement with the expected performance. The measured results show a receiver tracking threshold of -158 dBm and a dynamic signal range of 88 dB.

Acquisition, Tracking, Pointing, and Line-of-Sight Control Laboratory Experiments for a Space-Based Bifocal Relay Mirror

DTIC Science & Technology

2002-01-01

fixed coordinate frame. The spacecraft is subjected to large angle maneuvers ; therefore, a quaternion formulation is used. The spacecraft uses rate...steering mirrors (small inertia). The wheel control laws are based on quaternion error and angular velocity error feedback . The derivation of the...Agrawal, M. Romano Spacecraft Research and Design Center Naval Postgraduate School Monterey, CA 93943 R. L. Brunson**, J. D. Dillow, D. H. Nelson, J. J

TDRS-M Spacecraft Lift and Mate

NASA Image and Video Library

2017-08-09

NASA's Tracking and Data Relay Satellite (TDRS-M) is stacked atop the United Launch Alliance Atlas V Centaur upper stage. It will be the latest spacecraft destined for the agency's constellation of communications satellites that allows nearly continuous contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. Liftoff atop the ULA Atlas V rocket is scheduled to take place from Cape Canaveral's Space Launch Complex 41 on Aug. 18, 2017.

The National Aeronautics and Space Administration (NASA) Tracking and Data Relay Satellite System (TDRSS) program Economic and programmatic, considerations

NASA Technical Reports Server (NTRS)

Aller, R. O.

1985-01-01

The Tracking and Data Relay Satellite System (TDRSS) represents the principal element of a new space-based tracking and communication network which will support NASA spaceflight missions in low earth orbit. In its complete configuration, the TDRSS network will include a space segment consisting of three highly specialized communication satellites in geosynchronous orbit, a ground segment consisting of an earth terminal, and associated data handling and control facilities. The TDRSS network has the objective to provide communication and data relay services between the earth-orbiting spacecraft and their ground-based mission control and data handling centers. The first TDRSS spacecraft has been now in service for two years. The present paper is concerned with the TDRSS experience from the perspective of the various programmatic and economic considerations which relate to the program.

Voyager backgrounder

NASA Technical Reports Server (NTRS)

1981-01-01

The Voyager spacecraft and experiments are described. The spacecraft description includes the structure and configuration, communications systems, power supplies, computer command subsystems, and the science platform. The experiments discussed are investigations of cosmic rays, low-energy charged particles, magnetic fields, and plasma waves, along with studies in radio astronomy photopolarimetry. The tracking and data acquisition procedures for the missions are presented.

GRACE Follow-On Satellites Separating from Spacecraft (Artist's Concept)

NASA Image and Video Library

2018-04-30

Illustration of the twin spacecraft of the NASA/German Research Centre for Geosciences (GFZ) Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) mission. GRACE-FO will continue tracking the evolution of Earth's water cycle by monitoring changes in the distribution of mass on Earth. https://photojournal.jpl.nasa.gov/catalog/PIA22447

TDRS-L Media Day

NASA Image and Video Library

2014-01-03

TITUSVILLE, Fla. – Inside the Astrotech payload processing facility in Titusville, members of the news media are given an opportunity for an up-close look at the payload fairing that will encapsulate the Tracking and Data Relay Satellite, or TDRS-L, spacecraft. Journalists visited Astrotech as part of TDRS-L Media Day to conduct interviews and photograph the satellite that will be a part of the second of three next-generation spacecraft designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. For more information, visit: http://www.nasa.gov/mission_pages/tdrs/home/index.html

Probing the solar corona with very long baseline interferometry.

PubMed

Soja, B; Heinkelmann, R; Schuh, H

2014-06-20

Understanding and monitoring the solar corona and solar wind is important for many applications like telecommunications or geomagnetic studies. Coronal electron density models have been derived by various techniques over the last 45 years, principally by analysing the effect of the corona on spacecraft tracking. Here we show that recent observational data from very long baseline interferometry (VLBI), a radio technique crucial for astrophysics and geodesy, could be used to develop electron density models of the Sun's corona. The VLBI results agree well with previous models from spacecraft measurements. They also show that the simple spherical electron density model is violated by regional density variations and that on average the electron density in active regions is about three times that of low-density regions. Unlike spacecraft tracking, a VLBI campaign would be possible on a regular basis and would provide highly resolved spatial-temporal samplings over a complete solar cycle.

Worst-error analysis of batch filter and sequential filter in navigation problems. [in spacecraft trajectory estimation

NASA Technical Reports Server (NTRS)

Nishimura, T.

1975-01-01

This paper proposes a worst-error analysis for dealing with problems of estimation of spacecraft trajectories in deep space missions. Navigation filters in use assume either constant or stochastic (Markov) models for their estimated parameters. When the actual behavior of these parameters does not follow the pattern of the assumed model, the filters sometimes result in very poor performance. To prepare for such pathological cases, the worst errors of both batch and sequential filters are investigated based on the incremental sensitivity studies of these filters. By finding critical switching instances of non-gravitational accelerations, intensive tracking can be carried out around those instances. Also the worst errors in the target plane provide a measure in assignment of the propellant budget for trajectory corrections. Thus the worst-error study presents useful information as well as practical criteria in establishing the maneuver and tracking strategy of spacecraft's missions.

Optimal Variable-Structure Control Tracking of Spacecraft Maneuvers

NASA Technical Reports Server (NTRS)

Crassidis, John L.; Vadali, Srinivas R.; Markley, F. Landis

1999-01-01

An optimal control approach using variable-structure (sliding-mode) tracking for large angle spacecraft maneuvers is presented. The approach expands upon a previously derived regulation result using a quaternion parameterization for the kinematic equations of motion. This parameterization is used since it is free of singularities. The main contribution of this paper is the utilization of a simple term in the control law that produces a maneuver to the reference attitude trajectory in the shortest distance. Also, a multiplicative error quaternion between the desired and actual attitude is used to derive the control law. Sliding-mode switching surfaces are derived using an optimal-control analysis. Control laws are given using either external torque commands or reaction wheel commands. Global asymptotic stability is shown for both cases using a Lyapunov analysis. Simulation results are shown which use the new control strategy to stabilize the motion of the Microwave Anisotropy Probe spacecraft.

Apollo 13 spacecraft in trans-lunar trajectory

NASA Image and Video Library

1970-04-14

S70-34857 (13 April 1970) --- A telescopic photograph showing the Apollo 13 spacecraft in trans-lunar trajectory in the distant sky. Arrows point to the spacecraft, to the oxygen cloud, and to the expended Saturn V third stage. Apollo 13 was tracked at the Manned Spacecraft Center (MSC) using a 16 inch Schmidt-Cassegrain telescope with an IO television camera with an S-20 type IO tube, mounted in place of the eyepiece. The TV camera information is stored first on a data disc and played back on a viewing monitor from which this photograph was taken.

Digital Doppler measurement with spacecraft

NASA Technical Reports Server (NTRS)

Kinman, Peter W.; Hinedi, Sami M.; Labelle, Remi C.; Bevan, Roland P.; Del Castillo, Hector M.; Chong, Dwayne C.

1991-01-01

Digital and analog phase-locked loop (PLL) receivers were operated in parallel, each tracking the residual carrier from a spacecraft. The PLL tracked the downlink carrier and measured its instantaneous phase. This information, combined with a knowledge of the uplink carrier and the transponder ratio, permitted the computation of a Doppler observable. In this way, two separate Doppler measurements were obtained for one observation window. The two receivers agreed on the magnitude of the Doppler effect to within 1 mHz. There was less jitter on the data from the digital receiver. This was due to its smaller noise bandwidth. The demonstration and its results are described.

NASA requirements and applications environments for electrical power wiring

NASA Technical Reports Server (NTRS)

Stavnes, Mark W.; Hammoud, Ahmad N.

1992-01-01

Serious problems can occur from insulation failures in the wiring harnesses of aerospace vehicles. In most recorded incidents, the failures have been identified to be the result of arc tracking, the propagation of an arc along wiring bundles through degradation of insulation. Propagation of the arc can lead to the loss of the entire wiring harness and the functions which it supports. While an extensive database of testing for arc track resistant wire insulations has been developed for aircraft applications, the counterpart requirements for spacecraft are very limited. The electrical, thermal, mechanical, chemical, and operational requirements for specification and testing of candidate wiring systems for spacecraft applications is presented.

Planning Orbiter Flights

NASA Technical Reports Server (NTRS)

Harris, H. M.; Bergam, M. J.; Kim, S. L.; Smith, E. A.

1987-01-01

Shuttle Mission Design and Operations Software (SMDOS) assists in design and operation of missions involving spacecraft in low orbits around Earth by providing orbital and graphics information. SMDOS performs following five functions: display two world and two polar maps or any user-defined window 5 degrees high in latitude by 5 degrees wide in longitude in one of eight standard projections; designate Earth sites by points or polygon shapes; plot spacecraft ground track with 1-min demarcation lines; display, by means of different colors, availability of Tracking and Data Relay Satellite to Shuttle; and calculate available times and orbits to view particular site, and corresponding look angles. SMDOS written in Laboratory Micro-systems FORTH (1979 standard)

Tracking and data relay satellite system configuration and tradeoff study. Volume 1: Study summary

NASA Technical Reports Server (NTRS)

Hill, T. E.

1973-01-01

A study was conducted to determine the configuration and tradeoffs of a tracking and data relay satellite. The study emphasized the design of a three axis stabilized satellite and a telecommunications system optimized for support of low and medium data rate user spacecraft. Telecommunications support to low and high, or low medium, and high data rate users, considering launches with the Delta 2914, the Atlas/Centaur, and the space shuttle was also considered. The following subjects are presented: (1) launch and deployment profile, (2) spacecraft mechanical and structural design, (3) attitude stabilization and control subsystem, and (4) reliability analysis.

TDRS-L Liftoff

NASA Image and Video Library

2014-01-23

CAPE CANAVERAL, Fla. -- A United Launch Alliance Atlas V rocket streaks through the night sky over Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida, carrying NASA's Tracking and Data Relay Satellite, or TDRS-L, to Earth orbit. Launch was at 9:33 p.m. EST Jan. 23 during a 40-minute launch window. The TDRS-L spacecraft is the second of three new satellites designed to ensure vital operational continuity for NASA by expanding the lifespan of the Tracking and Data Relay Satellite System TDRSS fleet, which consists of eight satellites in geosynchronous orbit. The spacecraft provide tracking, telemetry, command and high-bandwidth data return services for numerous science and human exploration missions orbiting Earth. These include NASA's Hubble Space Telescope and the International Space Station. TDRS-L has a high-performance solar panel designed for more spacecraft power to meet the growing S-band communications requirements. TDRSS is one of three NASA Space Communication and Navigation SCaN networks providing space communications to NASA’s missions. For more information more about TDRS-L, visit http://www.nasa.gov/tdrs. To learn more about SCaN, visit www.nasa.gov/scan. Photo credit: NASA/Kim Shiflett

Spacecraft Attitude Tracking and Maneuver Using Combined Magnetic Actuators

NASA Technical Reports Server (NTRS)

Zhou, Zhiqiang

2010-01-01

The accuracy of spacecraft attitude control using magnetic actuators only is low and on the order of 0.4-5 degrees. The key reason is that the magnetic torque is two-dimensional and it is only in the plane perpendicular to the magnetic field vector. In this paper novel attitude control algorithms using the combination of magnetic actuators with Reaction Wheel Assembles (RWAs) or other types of actuators, such as thrusters, are presented. The combination of magnetic actuators with one or two RWAs aligned with different body axis expands the two-dimensional control torque to three-dimensional. The algorithms can guarantee the spacecraft attitude and rates to track the commanded attitude precisely. A design example is presented for Nadir pointing, pitch and yaw maneuvers. The results show that precise attitude tracking can be reached and the attitude control accuracy is comparable with RWAs based attitude control. The algorithms are also useful for the RWAs based attitude control. When there are only one or two workable RWAs due to RWA failures, the attitude control system can switch to the control algorithms for the combined magnetic actuators with the RWAs without going to the safe mode and the control accuracy can be maintained.

Non-Random Spatial Distribution of Impacts in the Stardust Cometary Collector

NASA Technical Reports Server (NTRS)

Westphal, Andrew J.; Bastien, Ronald K.; Borg, Janet; Bridges, John; Brownlee, Donald E.; Burchell, Mark J.; Cheng, Andrew F.; Clark, Benton C.; Djouadi, Zahia; Floss, Christine

2007-01-01

In January 2004, the Stardust spacecraft flew through the coma of comet P81/Wild2 at a relative speed of 6.1 km/sec. Cometary dust was collected at in a 0.1 sq m collector consisting of aerogel tiles and aluminum foils. Two years later, the samples successfully returned to earth and were recovered. We report the discovery that impacts in the Stardust cometary collector are not distributed randomly in the collecting media, but appear to be clustered on scales smaller than approx.10 cm. We also report the discovery of at least two populations of oblique tracks. We evaluated several hypotheses that could explain the observations. No hypothesis was consistent with all the observations, but the preponderance of evidence points toward at least one impact on the central Whipple shield of the spacecraft as the origin of both clustering and low-angle oblique tracks. High-angle oblique tracks unambiguously originate from a noncometary impact on the spacecraft bus just forward of the collector. Here we summarize the observations, and review the evidence for and against three scenarios that we have considered for explaining the impact clustering found on the Stardust aerogel and foil collectors.

Tracking and data relay satellite system configuration and tradeoff study. Volume 5: TDRS spacecraft design, part 1

NASA Technical Reports Server (NTRS)

1972-01-01

A dual spin stabilized TDR spacecraft design is presented for low data rate (LDR) and medium data rate (MDR) user spacecraft telecommunication relay service. The relay satellite provides command and data return channels for unmanned users together with duplex voice and data communication channels for manned user spacecraft. TDRS/ground links are in the Ku band. Command links are provided at UHF for LDR users and S band for MDR users. Voice communication channels are provided at UHF/VHF for LDR users and at S band for MDR users. The spacecraft is designed for launch on the Delta 2914 with system deployment planned for 1978. This volume contains a description of the overall TDR spacecraft configuration, a detailed description of the spacecraft subsystems, a reliability analysis, and a product effectiveness plan.

Standardization and economics of nuclear spacecraft: Executive summary

NASA Technical Reports Server (NTRS)

1973-01-01

Feasibility and cost benefits of nuclear-powered standardized spacecraft were investigated. The study indicates that two shuttle-launched nuclear-powered spacecraft should be able to serve the majority of unmanned NASA missions anticipated for the 1980's. The standard spacecraft include structure, thermal control, power, attitude control, some propulsion capability and tracking, telemetry, and command subsystems. One spacecraft design, powered by the radioisotope thermoelectric generator, can serve missions requiring up to 450 watts. The other spacecraft design, powered by similar nuclear heat sources in a Brayton-cycle generator, can serve missions requiring up to 2200 watts. Design concepts and trade-offs are discussed. The conceptual designs selected are presented and successfully tested against a variety of missions. The thermal design is such that both spacecraft are capable of operating in any earth orbit and any orientation without modification.

GPS NAVSTAR-4 and NTS-2 Long Term Frequency Stability and Time Transfer Analysis.

DTIC Science & Technology

1980-06-30

delta pseudo-range, are taken every 6 s. NTS Tracking Network Figure 4 presents the four station network employed for tracking the NTS spacecraft. Thc ...limits of visibility for the NRL CBD (Chesapeake Bay Division), Panama, Australia, and Eng- land tracking stations are depicted by the symbols C, P...GIAT and, in Australia, with the Division of National Mapping. The CBD tracking station had port- able clock and TV links to the U.S. Naval Observatory

The Dark Side of Saturn's Gravity

NASA Astrophysics Data System (ADS)

Iess, L.; Racioppa, P.; Durante, D.; Mariani, M., Jr.; Anabtawi, A.; Armstrong, J. W.; Gomez Casajus, L.; Tortora, P.; Zannoni, M.

2017-12-01

On July 19, 2017 the Cassini spacecraft successfully completed its sixth and last pericenter pass devoted to the investigation of Saturn's interior structure and rings. During each pass the spacecraft was tracked for about 24 hours by the antennas of NASA's Deep Space Network and ESA's ESTRACK network, providing high quality measurements of the spacecraft range rate. We report on a preliminary estimate of Saturn's gravity field and ring mass inferred from range rate observables, and discuss the surprising features of our findings.

Modeling and Data Analysis at the CCMC to Determine Threat of Spacecraft Surface Charging in Low Earth Orbit

NASA Astrophysics Data System (ADS)

Rastaetter, L.; Kuznetsova, M. M.; Zheng, Y.; Jordanova, V.; Yu, Y.; Minow, J. I.

2016-12-01

Spacecraft surface charging in Low-Earth Orbit occurs primarily in regions of low plasma density when precipitating electrons drive the spacecraft potential. Sudden changes in electric potentials occur when a spacecraft enters and leaves the sunlit region.At the Community Coordinated Modeling Center, we can employ a multitude of models of the ionosphere-thermosphere and inner magnetosphere to identify regions where spacecraft charging can occur based on thresholds of electron precipitation flux and energy and track the proximity of those areas to positions of satellites of interest. The identified regions will be validated and refined based on satellite observations. This work is in conjunction with the Spacecraft Charging Challenge organized by the GEM Workshop in collaboration with CCMC and the SHIELDS project at LANL.

Engineering evaluations and studies. Report for IUS studies

NASA Technical Reports Server (NTRS)

1981-01-01

The reviews, investigations, and analyses of the Inertial Upper Stage (IUS) Spacecraft Tracking and Data Network (STDN) transponder are reviewed. Carrier lock detector performance for Tracking and Data Relay Satellite System (TDRSS) dual-mode operation is discussed, as is the problem of predicting instantaneous frequency error in the carrier loop. Coastal loop performance analysis is critiqued and the static tracking phase error induced by thermal noise biases is discussed.

GLAS Spacecraft Pointing Study

NASA Technical Reports Server (NTRS)

Born, George H.; Gold, Kenn; Ondrey, Michael; Kubitschek, Dan; Axelrad, Penina; Komjathy, Attila

1998-01-01

Science requirements for the GLAS mission demand that the laser altimeter be pointed to within 50 m of the location of the previous repeat ground track. The satellite will be flown in a repeat orbit of 182 days. Operationally, the required pointing information will be determined on the ground using the nominal ground track, to which pointing is desired, and the current propagated orbit of the satellite as inputs to the roll computation algorithm developed by CCAR. The roll profile will be used to generate a set of fit coefficients which can be uploaded on a daily basis and used by the on-board attitude control system. In addition, an algorithm has been developed for computation of the associated command quaternions which will be necessary when pointing at targets of opportunity. It may be desirable in the future to perform the roll calculation in an autonomous real-time mode on-board the spacecraft. GPS can provide near real-time tracking of the satellite, and the nominal ground track can be stored in the on-board computer. It will be necessary to choose the spacing of this nominal ground track to meet storage requirements in the on-board environment. Several methods for generating the roll profile from a sparse reference ground track are presented.

Differenced Range Versus Integrated Doppler (DRVID) ionospheric analysis of metric tracking in the Tracking and Data Relay Satellite System (TDRSS)

NASA Technical Reports Server (NTRS)

Radomski, M. S.; Doll, C. E.

1995-01-01

The Differenced Range (DR) Versus Integrated Doppler (ID) (DRVID) method exploits the opposition of high-frequency signal versus phase retardation by plasma media to obtain information about the plasma's corruption of simultaneous range and Doppler spacecraft tracking measurements. Thus, DR Plus ID (DRPID) is an observable independent of plasma refraction, while actual DRVID (DR minus ID) measures the time variation of the path electron content independently of spacecraft motion. The DRVID principle has been known since 1961. It has been used to observe interplanetary plasmas, is implemented in Deep Space Network tracking hardware, and has recently been applied to single-frequency Global Positioning System user navigation This paper discusses exploration at the Goddard Space Flight Center (GSFC) Flight Dynamics Division (FDD) of DRVID synthesized from simultaneous two-way range and Doppler tracking for low Earth-orbiting missions supported by the Tracking and Data Relay Satellite System (TDRSS) The paper presents comparisons of actual DR and ID residuals and relates those comparisons to predictions of the Bent model. The complications due to the pilot tone influence on relayed Doppler measurements are considered. Further use of DRVID to evaluate ionospheric models is discussed, as is use of DRPID in reducing dependence on ionospheric modeling in orbit determination.

Using neuromorphic optical sensors for spacecraft absolute and relative navigation

NASA Astrophysics Data System (ADS)

Shake, Christopher M.

We develop a novel attitude determination system (ADS) for use on nano spacecraft using neuromorphic optical sensors. The ADS intends to support nano-satellite operations by providing low-cost, low-mass, low-volume, low-power, and redundant attitude determination capabilities with quick and straightforward onboard programmability for real time spacecraft operations. The ADS is experimentally validated with commercial-off-the-shelf optical devices that perform sensing and image processing on the same circuit board and are biologically inspired by insects' vision systems, which measure optical flow while navigating in the environment. The firmware on the devices is modified to both perform the additional biologically inspired task of tracking objects and communicate with a PC/104 form-factor embedded computer running Real Time Application Interface Linux used on a spacecraft simulator. Algorithms are developed for operations using optical flow, point tracking, and hybrid modes with the sensors, and the performance of the system in all three modes is assessed using a spacecraft simulator in the Advanced Autonomous Multiple Spacecraft (ADAMUS) laboratory at Rensselaer. An existing relative state determination method is identified to be combined with the novel ADS to create a self-contained navigation system for nano spacecraft. The performance of the method is assessed in simulation and found not to match the results from its authors using only conditions and equations already published. An improved target inertia tensor method is proposed as an update to the existing relative state method, but found not to perform as expected, but is presented for others to build upon.

Energy spectrum of 50-250 MeV/nucleon iron nuclei inside the MIR space craft.

PubMed

Gunther, W; Leugner, D; Becker, E; Heinrich, W; Reitz, G

2002-10-01

Stacks of CR-39 plastic nuclear track detectors were mounted inside the MIR spacecraft during the EUROMIR95 space mission for a period of 6 months. This long exposure time resulted in a large number of tracks of HZE-particles in the detector foils. All trajectories of stopping iron nuclei could be reconstructed by optimizing the etching conditions so that an automatic track measurement using image analysis techniques was possible. We found 185 stopping iron nuclei and used the énergy-range relation to calculate their energies at the stack surface. The measured spectrum of iron nuclei inside the MIR station is compared to results of model predictions considering the effect of the solar modulation for the mission period, the geomagnetic shielding effect for the MIR orbit and the shielding by material of the spacecraft walls and its instrumentation. c2002 Elsevier Science Ltd. All rights reserved.

Video guidance, landing, and imaging systems

NASA Technical Reports Server (NTRS)

Schappell, R. T.; Knickerbocker, R. L.; Tietz, J. C.; Grant, C.; Rice, R. B.; Moog, R. D.

1975-01-01

The adaptive potential of video guidance technology for earth orbital and interplanetary missions was explored. The application of video acquisition, pointing, tracking, and navigation technology was considered to three primary missions: planetary landing, earth resources satellite, and spacecraft rendezvous and docking. It was found that an imaging system can be mechanized to provide a spacecraft or satellite with a considerable amount of adaptability with respect to its environment. It also provides a level of autonomy essential to many future missions and enhances their data gathering ability. The feasibility of an autonomous video guidance system capable of observing a planetary surface during terminal descent and selecting the most acceptable landing site was successfully demonstrated in the laboratory. The techniques developed for acquisition, pointing, and tracking show promise for recognizing and tracking coastlines, rivers, and other constituents of interest. Routines were written and checked for rendezvous, docking, and station-keeping functions.

KSC-2009-5198

NASA Image and Video Library

2009-09-12

CAPE CANAVERAL, Fla. – Inside the mobile service tower on Launch Pad 17-B at Cape Canaveral Air Force Station in Florida, workers check the progress of the fairing being moved toward the Space Tracking and Surveillance System – Demonstrator spacecraft for encapsulation. The fairing is a two-part molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. STSS Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detection, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-4934 (09-22-09) Photo credit: NASA/Cory Huston

KSC-2009-5199

NASA Image and Video Library

2009-09-12

CAPE CANAVERAL, Fla. – Inside the mobile service tower on Launch Pad 17-B at Cape Canaveral Air Force Station in Florida, the Space Tracking and Surveillance System – Demonstrator spacecraft (foreground) is waiting for encapsulation in the fairing, behind it at left. The fairing is a two-part molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. STSS Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detection, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-4934 (09-22-09) Photo credit: NASA/Cory Huston

KSC-2009-5201

NASA Image and Video Library

2009-09-12

CAPE CANAVERAL, Fla. – Inside the mobile service tower on Launch Pad 17-B at Cape Canaveral Air Force Station in Florida, workers help guide the fairing (at right) into place around the Space Tracking and Surveillance System – Demonstrator spacecraft for encapsulation. The fairing is a two-part molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. STSS Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detection, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-4934 (09-22-09) Photo credit: NASA/Cory Huston

KSC-2009-5205

NASA Image and Video Library

2009-09-12

CAPE CANAVERAL, Fla. – Inside the mobile service tower on Launch Pad 17-B at Cape Canaveral Air Force Station in Florida, the second half of the fairing is being moved toward the Space Tracking and Surveillance System – Demonstrator spacecraft. The fairing is a two-part molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. STSS Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detection, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-4934 (09-22-09) Photo credit: NASA/Cory Huston

KSC-2009-5202

NASA Image and Video Library

2009-09-12

CAPE CANAVERAL, Fla. – Inside the mobile service tower on Launch Pad 17-B at Cape Canaveral Air Force Station in Florida, the first half of the two-part fairing is in place around the Space Tracking and Surveillance System – Demonstrator spacecraft. The fairing is a molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. STSS Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detection, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-4934 (09-22-09) Photo credit: NASA/Cory Huston

KSC-2009-5196

NASA Image and Video Library

2009-09-12

CAPE CANAVERAL, Fla. – Inside the mobile service tower on Launch Pad 17-B at Cape Canaveral Air Force Station in Florida, the Space Tracking and Surveillance System – Demonstrator spacecraft is waiting for encapsulation in the fairing. The fairing is a two-part molded structure that fits flush with the outside surface of the rocket and forms an aerodynamically smooth nose cone, protecting the spacecraft during launch and ascent. STSS Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detection, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-4934 (09-22-09) Photo credit: NASA/Cory Huston

Analysis on Tracking Schedule and Measurements Characteristics for the Spacecraft on the Phase of Lunar Transfer and Capture

NASA Astrophysics Data System (ADS)

Song, Young-Joo; Choi, Su-Jin; Ahn, Sang-il; Sim, Eun-Sup

2014-03-01

In this work, the preliminary analysis on both the tracking schedule and measurements characteristics for the spacecraft on the phase of lunar transfer and capture is performed. To analyze both the tracking schedule and measurements characteristics, lunar transfer and capture phases¡¯ optimized trajectories are directly adapted from former research, and eleven ground tracking facilities (three Deep Space Network sties, seven Near Earth Network sites, one Daejeon site) are assumed to support the mission. Under these conceptual mission scenarios, detailed tracking schedules and expected measurement characteristics during critical maneuvers (Trans Lunar Injection, Lunar Orbit Insertion and Apoapsis Adjustment Maneuver), especially for the Deajeon station, are successfully analyzed. The orders of predicted measurements' variances during lunar capture phase according to critical maneuvers are found to be within the order of mm/s for the range and micro-deg/s for the angular measurements rates which are in good agreement with the recommended values of typical measurement modeling accuracies for Deep Space Networks. Although preliminary navigation accuracy guidelines are provided through this work, it is expected to give more practical insights into preparing the Korea's future lunar mission, especially for developing flight dynamics subsystem.

Data base architecture for instrument characteristics critical to spacecraft conceptual design

NASA Technical Reports Server (NTRS)

Rowell, Lawrence F.; Allen, Cheryl L.

1990-01-01

Spacecraft designs are driven by the payloads and mission requirements that they support. Many of the payload characteristics, such as mass, power requirements, communication requirements, moving parts, and so forth directly affect the choices for the spacecraft structural configuration and its subsystem design and component selection. The conceptual design process, which translates mission requirements into early spacecraft concepts, must be tolerant of frequent changes in the payload complement and resource requirements. A computer data base was designed and implemented for the purposes of containing the payload characteristics pertinent for spacecraft conceptual design, tracking the evolution of these payloads over time, and enabling the integration of the payload data with engineering analysis programs for improving the efficiency in producing spacecraft designs. In-house tools were used for constructing the data base and for performing the actual integration with an existing program for optimizing payload mass locations on the spacecraft.

Coincidence probabilities for spacecraft gravitational wave experiments - Massive coalescing binaries

NASA Technical Reports Server (NTRS)

Tinto, Massimo; Armstrong, J. W.

1991-01-01

Massive coalescing binary systems are candidate sources of gravitational radiation in the millihertz frequency band accessible to spacecraft Doppler tracking experiments. This paper discusses signal processing and detection probability for waves from coalescing binaries in the regime where the signal frequency increases linearly with time, i.e., 'chirp' signals. Using known noise statistics, thresholds with given false alarm probabilities are established for one- and two-spacecraft experiments. Given the threshold, the detection probability is calculated as a function of gravitational wave amplitude for both one- and two-spacecraft experiments, assuming random polarization states and under various assumptions about wave directions. This allows quantitative statements about the detection efficiency of these experiments and the utility of coincidence experiments. In particular, coincidence probabilities for two-spacecraft experiments are insensitive to the angle between the directions to the two spacecraft, indicating that near-optical experiments can be done without constraints on spacecraft trajectories.

Tracking and data acquisition system for the 1990's. Volume 7: TDAS space technology assessment

NASA Technical Reports Server (NTRS)

Khatri, R.

1983-01-01

The results of the TDAS and user spacecraft technology assessment effort are provided. For each TDAS Satellite enhancement and user spacecraft element previously enumerated, the technology issues are identified and the R&D needed to resolve these issues is delineated. Subsequently, taking into account developments taking place elsewhere, the addition unique TDAS satellite module and user spacecraft element R&D efforts needed are identified, and conclusions are drawn in each case. From these conclusions, it is evident that with additional unique R&D efforts carried out for TDAS and appropriate user spacecraft elements the desired TDAS' capabilities for the 1990's can be realized and user spacecraft can be implemented that adequately interface with the projected TDAS.

TDRS-M Spacecraft Processing at Astrotech

NASA Image and Video Library

2017-07-13

Inside the Astrotech facility in Titusville, Florida, NASA's Tracking and Data Relay Satellite, TDRS-M, is undergoing final checkouts in a test cell behind a large door. The spacecraft soon will be encapsulated in its payload fairing, seen on the right. TDRS-M is the latest spacecraft destined for the agency's constellation of communications satellites that allows nearly continuous contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. Liftoff atop a United Launch Alliance Atlas V rocket is scheduled to take place from Space Launch Complex 41 at Cape Canaveral Air Force Station at 9:02 a.m. EDT Aug. 3, 2017.

The Sun Radio Imaging Space Experiment (SunRISE) Mission

NASA Astrophysics Data System (ADS)

Lazio, Joseph; Kasper, Justin; Maksimovic, Milan; Alibay, Farah; Amiri, Nikta; Bastian, Tim; Cohen, Christina; Landi, Enrico; Manchester, Ward; Reinard, Alysha; Schwadron, Nathan; Cecconi, Baptiste; Hallinan, Gregg; Hegedus, Alex; Krupar, Vratislav; Zaslavsky, Arnaud

2017-04-01

Radio emission from coronal mass ejections (CMEs) is a direct tracer of particle acceleration in the inner heliosphere and potential magnetic connections from the lower solar corona to the larger heliosphere. Energized electrons excite Langmuir waves, which then convert into intense radio emission at the local plasma frequency, with the most intense acceleration thought to occur within 20 RS. The radio emission from CMEs is quite strong such that only a relatively small number of antennas is required to detect and map it, but many aspects of this particle acceleration and transport remain poorly constrained. Ground-based arrays would be quite capable of tracking the radio emission associated with CMEs, but absorption by the Earth's ionosphere limits the frequency coverage of ground-based arrays (ν ≳ 15 MHz), which in turn limits the range of solar distances over which they can track the radio emission (≲ 3RS). The state-of-the-art for tracking such emission from space is defined by single antennas (Wind/WAVES, Stereo/SWAVES), in which the tracking is accomplished by assuming a frequency-to-density mapping; there has been some success in triangulating the emission between the spacecraft, but considerable uncertainties remain. We describe the Sun Radio Imaging Space Experiment (SunRISE) mission concept: A constellation of small spacecraft in a geostationary graveyard orbit designed to localize and track radio emissions in the inner heliosphere. Each spacecraft would carry a receiving system for observations below 25 MHz, and SunRISE would produce the first images of CMEs more than a few solar radii from the Sun. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

The Sun Radio Imaging Space Experiment (SunRISE) Mission

NASA Astrophysics Data System (ADS)

Kasper, J. C.; Lazio, J.; Alibay, F.; Amiri, N.; Bastian, T.; Cohen, C.; Landi, E.; Hegedus, A. M.; Maksimovic, M.; Manchester, W.; Reinard, A.; Schwadron, N.; Cecconi, B.; Hallinan, G.; Krupar, V.

2017-12-01

Radio emission from coronal mass ejections (CMEs) is a direct tracer of particle acceleration in the inner heliosphere and potential magnetic connections from the lower solar corona to the larger heliosphere. Energized electrons excite Langmuir waves, which then convert into intense radio emission at the local plasma frequency, with the most intense acceleration thought to occur within 20 R_S. The radio emission from CMEs is quite strong such that only a relatively small number of antennas is required to detect and map it, but many aspects of this particle acceleration and transport remain poorly constrained. Ground-based arrays would be quite capable of tracking the radio emission associated with CMEs, but absorption by the Earth's ionosphere limits the frequency coverage of ground-based arrays (nu > 15 MHz), which in turn limits the range of solar distances over which they can track the radio emission (< 3 R_S). The state-of-the-art for tracking such emission from space is defined by single antennas (Wind/WAVES, Stereo/SWAVES), in which the tracking is accomplished by assuming a frequency-to-density mapping; there has been some success in triangulating the emission between the spacecraft, but considerable uncertainties remain. We describe the Sun Radio Imaging Space Experiment (SunRISE) mission concept: A constellation of small spacecraft in a geostationary graveyard orbit designed to localize and track radio emissions in the inner heliosphere. Each spacecraft would carry a receiving system for observations below 25 MHz, and SunRISE would produce the first images of CMEs more than a few solar radii from the Sun. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

Tape/head interface study

NASA Technical Reports Server (NTRS)

1983-01-01

Existing high energy tapes, high track density heads, and transport guidance techniques were evaluated and characterized to enable these technologies to be employed in future spacecraft recorders with high confidence. The results of these study efforts demonstrated tracking accuracy tape and head density that will support spacecraft recorders with data rates of a minimum of 150 Mbps and storage capacities ranging from 10 to the 10th to 10 to the 11th bits. Seven high energy tapes of either .25 in width, 1.00 in width, or both, were tested. All tapes were tested at the same speed (30 ips) and the same packing density (33 KBI). The performance of all 1 in tapes was considered superior.

Space Operations

DTIC Science & Technology

2009-01-06

enabling precise blue force tracking (BFT), enhancing joint force situational awareness, maneuverability, and command and control (C2... spacecraft , transmits the status of those systems to the control segment on the ground, and receives and processes instructions from the control segment...missions include the tracking , telemetry, and control operations of: (1) Ultrahigh frequency (UHF) follow-on satellite system and fleet

Using the Global Positioning System for Earth Orbiter and Deep Space Tracking

NASA Technical Reports Server (NTRS)

Lichten, Stephen M.

1994-01-01

The Global Positioning System (GPS) can play a major role in supporting orbit and trajectory determination for spacecraft in a wide range of applications, including low-Earth, high-Earth, and even deep space (interplanetary) tracking. This paper summarizes recent results demonstrating these unique and far-ranging applications of GPS.

Orbit-attitude coupled motion around small bodies: Sun-synchronous orbits with Sun-tracking attitude motion

NASA Astrophysics Data System (ADS)

Kikuchi, Shota; Howell, Kathleen C.; Tsuda, Yuichi; Kawaguchi, Jun'ichiro

2017-11-01

The motion of a spacecraft in proximity to a small body is significantly perturbed due to its irregular gravity field and solar radiation pressure. In such a strongly perturbed environment, the coupling effect of the orbital and attitude motions exerts a large influence that cannot be neglected. However, natural orbit-attitude coupled dynamics around small bodies that are stationary in both orbital and attitude motions have yet to be observed. The present study therefore investigates natural coupled motion that involves both a Sun-synchronous orbit and Sun-tracking attitude motion. This orbit-attitude coupled motion enables a spacecraft to maintain its orbital geometry and attitude state with respect to the Sun without requiring active control. Therefore, the proposed method can reduce the use of an orbit and attitude control system. This paper first presents analytical conditions to achieve Sun-synchronous orbits and Sun-tracking attitude motion. These analytical solutions are then numerically propagated based on non-linear coupled orbit-attitude equations of motion. Consequently, the possibility of implementing Sun-synchronous orbits with Sun-tracking attitude motion is demonstrated.

On the Effects of a Spacecraft Subcarrier Unbalanced Modulator

NASA Technical Reports Server (NTRS)

Nguyen, Tien Manh

1993-01-01

This paper presents mathematical models with associated analysis of the deleterious effects which a spacecraft's subcarrier unbalanced modulator has on the performance of a phase-modulated residual carrier communications link. The undesired spectral components produced by the phase and amplitude imbalances in the subcarrier modulator can cause (1) potential interference to the carrier tracking and (2) degradation in the telemetry bit signal-to-noise ratio (SNR). A suitable model for the unbalanced modulator is developed and the threshold levels of undesired components that fall into the carrier tracking loop are determined. The distribution of the carrier phase error caused by the additive White Gaussian noise (AWGN) and undesired component at the residual RF carrier is derived for the limiting cases. Further, this paper analyses the telemetry bit signal-to-noise ratio degradations due to undesirable spectral components as well as the carrier tracking phase error induced by phase and amplitude imbalances. Numerical results which indicate the sensitivity of the carrier tracking loop and the telemetry symbol-error rate (SER) to various parameters of the models are also provided as a tool in the design of the subcarrier balanced modulator.

Galileo Spacecraft Scan Platform Celestial Pointing Cone Control Gain Redesign

NASA Technical Reports Server (NTRS)

In, C-H. C.; Hilbert, K. B.

1994-01-01

During September and October 1991, pictures of the Gaspra asteroid and neighboring stars were taken by the Galileo Optical Navigation (OPNAV) Team for the purpose of navigation the spacecraft for a successful Gaspra encounter. The star tracks in these pictures showed that the scan platform celestial pointing cone controller performed poorly in compensating for wobble-induced cone offsets.

FMT (Flight Software Memory Tracker) For Cassini Spacecraft-Software Engineering Using JAVA

NASA Technical Reports Server (NTRS)

Kan, Edwin P.; Uffelman, Hal; Wax, Allan H.

1997-01-01

The software engineering design of the Flight Software Memory Tracker (FMT) Tool is discussed in this paper. FMT is a ground analysis software set, consisting of utilities and procedures, designed to track the flight software, i.e., images of memory load and updatable parameters of the computers on-board Cassini spacecraft. FMT is implemented in Java.

Determination of the System Mass and the Individual Masses of Pluto and Charon from New Horizons Radio Tracking

NASA Astrophysics Data System (ADS)

Hahn, M.; Paetzold, M.; Andert, T.; Bird, M. K.; Tyler, G. L.; Hinson, D. P.; Linscott, I.; Stern, A.; Weaver, H. A., Jr.; Young, L. A.; Ennico Smith, K.; Olkin, C.

2016-12-01

One objective of the New Horizons Radio Science Experiment REX is the direct determination of the system mass and the individual masses of Pluto and Charon. About four weeks of two-way radio tracking centered around the closest approach of New Horizons to the Pluto system were processed. Major problems during the processing were the changes in spacecraft attitude by thrusters which applied extra Δv to the spacecraft motion masking partially the continuously perturbed motion caused by the attracting forces of the Pluto system members. The times of the spacecraft thruster activity are known but the applied Δv magnitude needed to be specifically adjusted. No two-way tracking was available during the flyby day on 14th July but slots of the REX one-way uplink observations cover the most important time near closest approach, these are for example the Pluto and Charon Earth occultation entries and exits. The REX data during the flyby day allowed to extract the individual masses of Pluto and Charon from the system mass at high precision. The relative errors of the mass determinations are below 0.02% and 0.2%, respectively. The masses of the 4 small satellites in the Pluto system could not be resolved.

TDRS-M Spacecraft Encapsulation

NASA Image and Video Library

2017-08-02

Inside the Astrotech facility in Titusville, Florida, NASA's Tracking and Data Relay Satellite, TDRS-M, is encapsulated into ULA's Atlas V payload fairing. TDRS-M is the latest spacecraft destined for the agency's constellation of communications satellites that allows nearly continuous contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. Liftoff atop a United Launch Alliance Atlas V rocket is scheduled to take place from Space Launch Complex 41 at Cape Canaveral Air Force Station at 8:03 a.m. EDT Aug. 18, 2017.

KSC-02pd1579

NASA Image and Video Library

2002-10-18

KENNEDY SPACE CENTER, FLA. - The TDRS-J spacecraft, enclosed in a container, arrives at the Spacecraft Assembly and Encapsulation Facility-2 (SAEF-2) for processing. The Tracking and Data Relay Satellite System is the primary source of space-to-ground voice, data and telemetry for the Space Shuttle. It also provides communications with the International Space Station and scientific spacecraft in low-earth orbit such as the Hubble Space Telescope, and launch support for some expendable vehicles. This new advanced series of satellites will extend the availability of TDRS communications services until approximately 2017.

Stardust Interstellar Preliminary Examination V: XRF Analyses of Interstellar Dust Candidates at ESRF ID13

NASA Technical Reports Server (NTRS)

Brenker, Frank E.; Westphal, Andrew J.; Simionovici, Alexandre S.; Flynn, George J.; Gainsforth, Zack; Allen, Carlton C.; Sanford, Scott; Zolensky, Michael E.; Bastien, Ron K.; Frank, David R.

2014-01-01

Here, we report analyses by synchrotron X-ray fluorescence microscopy of the elemental composition of eight candidate impact features extracted from the Stardust Interstellar Dust Collector (SIDC). Six of the features were unambiguous tracks, and two were crater-like features. Five of the tracks are so-called midnight tracks that is, they had trajectories consistent with an origin either in the interstellar dust stream or as secondaries from impacts on the Sample Return Capsule (SRC). In a companion paper reporting synchrotron X-ray diffraction analyses of ISPE candidates, we show that two of these particles contain natural crystalline materials: the terminal particle of track 30contains olivine and spinel, and the terminal particle of track 34 contains olivine. Here, we show that the terminal particle of track 30, Orion, shows elemental abundances, normalized to Fe, that are close to CI values, and a complex, fine-grained structure. The terminal particle of track 34, Hylabrook, shows abundances that deviate strongly from CI, but shows little fine structure and is nearly homogenous. The terminal particles of other midnight tracks, 29 and 37, had heavy element abundances below detection threshold. A third, track28, showed a composition inconsistent with an extraterrestrial origin, but also inconsistent with known spacecraft materials. A sixth track, with a trajectory consistent with secondary ejecta from an impact on one of the spacecraft solar panels, contains abundant Ce and Zn. This is consistent with the known composition of the glass covering the solar panel. Neither crater-like feature is likely to be associated with extraterrestrial materials. We also analyzed blank aerogel samples to characterize background and variability between aerogel tiles. We found significant differences in contamination levels and compositions, emphasizing the need for local background subtraction for accurate quantification.

Line drawing titled 'TDRS Spacecraft On-Orbit Configuration'

NASA Technical Reports Server (NTRS)

1988-01-01

Line drawing titled 'TDRS Spacecraft On-Orbit Configuration' identifies the various tracking and data relay satellite (TDRS) components (solar arrays, C-Band antenna, K-Band antenna, space ground link (SGL) antenna, single access antennas, multiple access antenna, omni antenna, solar sail). A TDRS will be deployed during the STS-26 mission. Including the space shuttle, the TDRS will be equipped to support up to 26 user spacecraft simultaneously. It will provide two types of service: 1) multiple access which can relay data from as many as 20 low data rate (100 bits per second to 50 kilobits per second) user satellites simultaneously and; 2) single access which will provide two high data rate (to 300 megabits per second) communication relays. The TDRS is three-axis stabilizrd with the body fixed antennas pointing constantly at the Earth while the solar arrays track the Sun. TDR satellites do no processing of user traffic in either direction. Rather, they operate as 'bent pipe' repeaters,

TDRS-L Media Day

NASA Image and Video Library

2014-01-03

TITUSVILLE, Fla. – Members of the news media are given an up-close look at the Tracking and Data Relay Satellite, or TDRS-L, spacecraft undergoing preflight processing inside the Astrotech payload processing facility in Titusville. TDRS-L is being prepared for encapsulation inside its payload fairing prior to being transported to Launch Complex 41 at Cape Canaveral Air Force Station. Journalists visited Astrotech as part of TDRS-L Media Day to conduct interviews and photograph the satellite that will be a part of the second of three next-generation spacecraft designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. For more information, visit: http://www.nasa.gov/mission_pages/tdrs/home/index.html

Independent Confirmation of the Pioneer 10 Anomalous Acceleration

NASA Technical Reports Server (NTRS)

Markwardt, Craig B.

2002-01-01

I perform an independent analysis of radio Doppler tracking data from the Pioneer 10 spacecraft for the time period 1987-1994. All of the tracking data were taken from public archive sources, and the analysis tools were developed independently by myself. I confirm that an apparent anomalous acceleration is acting on the Pioneer 10 spacecraft, which is not accounted for by present physical models of spacecraft navigation. My best fit value for the acceleration, including corrections for systematic biases and uncertainties, is (8.60 plus or minus 1.34) x 10(exp -8) centimeters per second, directed towards the Sun. This value compares favorably to previous results. I examine the robustness of my result to various perturbations of the analysis method, and find agreement to within plus or minus 5%. The anomalous acceleration is reasonably constant with time, with a characteristic variation time scale of greater than 70 yr. Such a variation timescale is still too short to rule out on-board thermal radiation effects, based on this particular Pioneer 10 data set.

Artificial Immune System for Recognizing Patterns

NASA Technical Reports Server (NTRS)

Huntsberger, Terrance

2005-01-01

A method of recognizing or classifying patterns is based on an artificial immune system (AIS), which includes an algorithm and a computational model of nonlinear dynamics inspired by the behavior of a biological immune system. The method has been proposed as the theoretical basis of the computational portion of a star-tracking system aboard a spacecraft. In that system, a newly acquired star image would be treated as an antigen that would be matched by an appropriate antibody (an entry in a star catalog). The method would enable rapid convergence, would afford robustness in the face of noise in the star sensors, would enable recognition of star images acquired in any sensor or spacecraft orientation, and would not make an excessive demand on the computational resources of a typical spacecraft. Going beyond the star-tracking application, the AIS-based pattern-recognition method is potentially applicable to pattern- recognition and -classification processes for diverse purposes -- for example, reconnaissance, detecting intruders, and mining data.

Orbit determination error analysis and comparison of station-keeping costs for Lissajous and halo-type libration point orbits and sensitivity analysis using experimental design techniques

NASA Technical Reports Server (NTRS)

Gordon, Steven C.

1993-01-01

Spacecraft in orbit near libration point L1 in the Sun-Earth system are excellent platforms for research concerning solar effects on the terrestrial environment. One spacecraft mission launched in 1978 used an L1 orbit for nearly 4 years, and future L1 orbital missions are also being planned. Orbit determination and station-keeping are, however, required for these orbits. In particular, orbit determination error analysis may be used to compute the state uncertainty after a predetermined tracking period; the predicted state uncertainty levels then will impact the control costs computed in station-keeping simulations. Error sources, such as solar radiation pressure and planetary mass uncertainties, are also incorporated. For future missions, there may be some flexibility in the type and size of the spacecraft's nominal trajectory, but different orbits may produce varying error analysis and station-keeping results. The nominal path, for instance, can be (nearly) periodic or distinctly quasi-periodic. A periodic 'halo' orbit may be constructed to be significantly larger than a quasi-periodic 'Lissajous' path; both may meet mission requirements, but perhaps the required control costs for these orbits are probably different. Also for this spacecraft tracking and control simulation problem, experimental design methods can be used to determine the most significant uncertainties. That is, these methods can determine the error sources in the tracking and control problem that most impact the control cost (output); it also produces an equation that gives the approximate functional relationship between the error inputs and the output.

Monitoring Spacecraft Telemetry Via Optical or RF Link

NASA Technical Reports Server (NTRS)

Fielhauer, K. B.; Boone, B. G.

2011-01-01

A patent disclosure document discusses a photonic method for connecting a spacecraft with a launch vehicle upper-stage telemetry system as a means for monitoring a spacecraft fs health and status during and right after separation and deployment. This method also provides an efficient opto-coupled capability for prelaunch built-in-test (BIT) on the ground to enable more efficient and timely integration, preflight checkout, and a means to obviate any local EMI (electromagnetic interference) during integration and test. Additional utility can be envisioned for BIT on other platforms, such as the International Space Station (ISS). The photonic telemetry system implements an optical free-space link with a divergent laser transmitter beam spoiled over a significant cone angle to accommodate changes in spacecraft position without having to angle track it during deployment. Since the spacecraft may lose attitude control and tumble during deployment, the transmitted laser beam interrogates any one of several low-profile meso-scale retro-reflective spatial light modulators (SLMs) deployed over the surface of the spacecraft. The return signal beam, modulated by the SLMs, contains health, status, and attitude information received back at the launch vehicle. Very compact low-power opto-coupler technology already exists for the received signal (requiring relatively low bandwidths, e.g., .200 kbps) to enable transfer to a forward pass RF relay from the launch vehicle to TDRSS (Tracking and Data Relay Satellite System) or another recipient. The link would be active during separation and post-separation to monitor spacecraft health, status, attitude, or other data inventories until attitude recovery and ground control can be re-established. An optical link would not interfere with the existing upper stage telemetry and beacon systems, thus meeting launch vehicle EMI environmental constraints.

Role of TDRSS in tracking and data acquisition

NASA Technical Reports Server (NTRS)

Spearing, R. E.

1980-01-01

The integration and operation of the Tracking Data Relay Satellite System (TDRSS) into the NASA Communications Network (NASCOM) equipment and services is described. The system concept employs spacecraft in geosynchronous orbit, operating as communications front-ends, and a single ground terminal, which provides primary tracking and data acquisition services for earth-orbiting user satellites and for the Space Shuttle. The TDRSS system is further characterized by real-time throughput of user data and a high degree of automation.

Autonomous subpixel satellite track end point determination for space-based images.

PubMed

Simms, Lance M

2011-08-01

An algorithm for determining satellite track end points with subpixel resolution in spaced-based images is presented. The algorithm allows for significant curvature in the imaged track due to rotation of the spacecraft capturing the image. The motivation behind the subpixel end point determination is first presented, followed by a description of the methodology used. Results from running the algorithm on real ground-based and simulated spaced-based images are shown to highlight its effectiveness.

The Telecommunications and Data Acquisition Report

NASA Technical Reports Server (NTRS)

Posner, E. C. (Editor)

1984-01-01

Tracking and ground-based navigation; communications, spacecraft-ground; station control and system technology; capabilities for new projects; networks consolidation program; and network sustaining are described.

Tracking Data Acquisition System (TDAS) for the 1990's. Volume 6: TDAS navigation system architecture

NASA Technical Reports Server (NTRS)

Elrod, B. D.; Jacobsen, A.; Cook, R. A.; Singh, R. N. P.

1983-01-01

One-way range and Doppler methods for providing user orbit and time determination are examined. Forward link beacon tracking, with on-board processing of independent navigation signals broadcast continuously by TDAS spacecraft; forward link scheduled tracking; with on-board processing of navigation data received during scheduled TDAS forward link service intervals; and return link scheduled tracking; with ground-based processing of user generated navigation data during scheduled TDAS return link service intervals are discussed. A system level definition and requirements assessment for each alternative, an evaluation of potential navigation performance and comparison with TDAS mission model requirements is included. TDAS satellite tracking is also addressed for two alternatives: BRTS and VLBI tracking.

The community satellite 1. [social implications of ATS 6

NASA Technical Reports Server (NTRS)

1974-01-01

NASA's Applications Technology Satellite-6 is being used to test a variety of new space communications concepts requiring the use of a geosynchronous-orbit spacecraft. These include broadcast of health and education television programs to small, low-cost ground receiving units in remote regions. Other studies to be conducted are related to aeronautical and maritime communications, position-location, and traffic-control techniques. Questions concerning spacecraft tracking and data relay are also investigated. The 1,402 kg spacecraft consists essentially of an Earth Viewing Module connected to a deployable reflector antenna. Details regarding the planned experiments and the spacecraft design are discussed and a brief history of the ATS program is presented.

Solar wind data from the MIT plasma experiments on Pioneer 6 and Pioneer 7

NASA Technical Reports Server (NTRS)

Lazarus, A. J.; Heinemann, M. A.; Mckinnis, R. W.; Bridge, H. S.

1973-01-01

Hourly averages are presented of solar wind proton parameters obtained from experiments on the Pioneer 6 and Pioneer 7 spacecraft during the period December 16, 1965 to August 1971. The number of data points available on a given day depends upon the spacecraft-earth distance, the telemetry bit rate, and the ground tracking time allotted to each spacecraft. Thus, the data obtained earlier in the life of each spacecraft are more complete. The solar wind parameters are given in the form of plots and listings. Trajectory information is also given along with a detailed description of the analysis procedures used to extract plasma parameters from the measured data.

Mars Observer trajectory and orbit design

NASA Technical Reports Server (NTRS)

Beerer, Joseph G.; Roncoli, Ralph B.

1991-01-01

The Mars Observer launch, interplanetary, Mars orbit insertion, and mapping orbit designs are described. The design objective is to enable a near-maximum spacecraft mass to be placed in orbit about Mars. This is accomplished by keeping spacecraft propellant requirements to a minimum, selecting a minimum acceptable launch period, equalizing the spacecraft velocity change requirement at the beginning and end of the launch period, and constraining the orbit insertion maneuvers to be coplanar. The mapping orbit design objective is to provide the opportunity for global observation of the planet by the science instruments while facilitating the spacecraft design. This is realized with a sun-synchronous near-polar orbit whose ground-track pattern covers the planet at progressively finer resolution.

The New Space Network: the Tracking and Data Relay Satellite System

NASA Technical Reports Server (NTRS)

Froehlich, W.

1986-01-01

When the Tracking and Data Relay Satellite System (TDRSS)is completed, the system, together with its various NASA support elements will be known simply as the Space Networks. It will substantially increase information exchanges between low-orbiting spacecraft and the ground. The structural design, functions, earth-based links, and present and future use are discussed.

Arc tracking of cables for space applications

NASA Technical Reports Server (NTRS)

Koenig, D.; Frontzek, F. R.; Hanson, J.; Reher, H. J.; Judd, M. D.; Bryant, D.

1995-01-01

The main objective of this study is to develop a new test method that is suitable for the assessment of the resistance of aerospace cables to arc tracking for different specific environmental and network conditions of spacecrafts. This paper reports the purpose, test conditions, test specimen, test procedure, and test acceptance criteria of seven different (200-250 mm long) cables.

Position Extrema in Keplerian Relative Motion: A Gröbner Basis Approach

NASA Astrophysics Data System (ADS)

Allgeier, Shawn E.; Fitz-Coy, Norman G.; Erwin, R. Scott

2012-12-01

This paper analyzes the relative motion between two spacecraft in orbit. Specifically, the paper provides bounds for relative spacecraft position-based measures which impact spacecraft formation-flight mission design and analysis. Previous efforts have provided bounds for the separation distance between two spacecraft. This paper presents a methodology for bounding the local vertical, horizontal, and cross track components of the relative position vector in a spacecraft centered, rotating reference frame. Three metrics are derived and a methodology for bounding them is presented. The solution of the extremal equations for the metrics is formulated as an affine variety and obtained using a Gröbner basis reduction. No approximations are utilized and the only assumption is that the two spacecraft are in bound Keplerian orbits. Numerical examples are included to demonstrate the efficacy of the method. The metrics have utility to the mission designer of formation flight architectures, with relevance to Earth observation constellations.

Mercury's gravity field, orientation, and ephemeris after MESSENGER's Low-Altitude Campaign

NASA Astrophysics Data System (ADS)

Genova, Antonio; Mazarico, Erwan; Goossens, Sander J.; Lemoine, Frank G.; Neumann, Gregory A.; Smith, David E.; Zuber, Maria T.; Solomon, Sean C.

2015-04-01

In April 2015, the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft will complete more than 4 years of operations in orbit around Mercury. In its last year, as part of MESSENGER's Second Extended Mission (XM2) started in March 2013, the spacecraft has been collecting radio tracking data at unprecedented low altitudes in Mercury's northern hemisphere. During the first two years in orbit, the spacecraft periapsis altitude was kept between 200 and 500 km, while its location drifted slowly northward from 60˚N to 84˚N. The orbital period initially was 12 h, but it was decreased to 8 h in April 2012. The remaining fuel onboard the spacecraft enabled two extended missions, the last of which will end with an impact expected on or before 28 April 2015. During the second extended mission, the periapsis altitude has been as low as 15-25 km. NASA's Deep Space Network (DSN) tracked the spacecraft during periapsis passages from April to October 2014, when the spacecraft periapsis altitude was between 25 and 100 km. In the last six months of the mission, the closest approaches of MESSENGER were occulted by Mercury and were thus not visible from Earth. However, additional radio tracking data have been collected at altitudes (75-100 km) that are still substantially below the initial periapsis altitude. The new low-altitude radio tracking data have enabled an updated model of the gravity field of Mercury. With these data, the resolution of the field in the northern hemisphere has been improved, revealing features that were previously undetectable and that correlate well with topography. The zonal harmonics are in good agreement with those in previous models of the gravity field. We also focused our study on the determination of other geophysical parameters, such as the orientation of Mercury. The new data were acquired not only at lower altitudes but also at latitudes closer to the equator, so they provide important information on tides, the right ascension of the pole, and the physical libration in longitude. The new model of Mercury's gravity field includes the estimation of the declination and the right ascension of the pole, the Love number k2, and the amplitude of the longitudinal libration. We also report an update on the ephemeris of Mercury obtained from MESSENGER range data covering the entire mission period, from the flybys until the end of the mission.

TDRS-M Live Launch Coverage

NASA Image and Video Library

2017-08-18

Live launch coverage of the Tracking and Data Relay Satellite, TDRS-M, liftoff at 8:39am EDT from Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. TDRS-M is the latest spacecraft destined for the agency's constellation of communications satellites that allows nearly continuous contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories.

Schema for Spacecraft-Command Dictionary

NASA Technical Reports Server (NTRS)

Laubach, Sharon; Garcia, Celina; Maxwell, Scott; Wright, Jesse

2008-01-01

An Extensible Markup Language (XML) schema was developed as a means of defining and describing a structure for capturing spacecraft command- definition and tracking information in a single location in a form readable by both engineers and software used to generate software for flight and ground systems. A structure defined within this schema is then used as the basis for creating an XML file that contains command definitions.

Orbit determination singularities in the Doppler tracking of a planetary orbiter

NASA Technical Reports Server (NTRS)

Wood, L. J.

1985-01-01

On a number of occasions, spacecraft launched by the U.S. have been placed into orbit about the moon, Venus, or Mars. It is pointed out that, in particular, in planetary orbiter missions two-way coherent Doppler data have provided the principal data type for orbit determination applications. The present investigation is concerned with the problem of orbit determination on the basis of Doppler tracking data in the case of a spacecraft in orbit about a natural body other than the earth or the sun. Attention is given to Doppler shift associated with a planetary orbiter, orbit determination using a zeroth-order model for the Doppler shift, and orbit determination using a first-order model for the Doppler shift.

Overview of the Miniature Sensor Technology Integration (MSTI) spacecraft attitude control system

NASA Technical Reports Server (NTRS)

Mcewen, Rob

1994-01-01

Msti2 is a small, 164 kg (362 lb), 3-axis stabilized, low-Earth-orbiting satellite whose mission is missile booster tracking. The spacecraft is actuated by 3 reaction wheels and 12 hot gas thrusters. It carries enough fuel for a projected life of 6 months. The sensor complement consists of a Horizon Sensor, a Sun Sensor, low-rate gyros, and a high rate gyro for despin. The total pointing control error allocation is 6 mRad (.34 Deg), and this is while tracking a target on the Earth's surface. This paper describes the Attitude Control System (ACS) algorithms which include the following: attitude acquisition (despin, Sun and Earth acquisition), attitude determination, attitude control, and linear stability analysis.

Integral sliding mode-based attitude coordinated tracking for spacecraft formation with communication delays

NASA Astrophysics Data System (ADS)

Zhang, Jian; Hu, Qinglei; Xie, Wenbo

2017-11-01

This paper investigates the attitude coordinated tracking control for a group of rigid spacecraft under directed communication topology, in which inertia uncertainties, external disturbances, input saturation and constant time-delays between the formation members are handled. Initially, the nominal system with communication delays is studied. A delay-dependent controller is proposed by using Lyapunov-Krasovskii function and sufficient condition for system stability is derived. Then, an integral sliding manifold is designed and adaptive control approach is employed to deal with the total perturbation. Meanwhile, the boundary layer method is introduced to alleviate the unexpected chattering as system trajectories cross the switching surface. Finally, numerical simulation results are presented to validate the effectiveness and robustness of the proposed control strategy.

Geodesy at Mercury with MESSENGER

NASA Technical Reports Server (NTRS)

Smith, David E.; Zuber, Maria t.; Peale, Stanley J.; Phillips, Roger J.; Solomon, Sean C.

2006-01-01

In 2011 the MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging) spacecraft will enter Mercury orbit and begin the mapping phase of the mission. As part of its science objectives the MESSENGER mission will determine the shape and gravity field of Mercury. These observations will enable the topography and the crustal thickness to be derived for the planet and will determine the small libration of the planet about its axis, the latter critical to constraining the state of the core. These measurements require very precise positioning of the MESSENGER spacecraft in its eccentric orbit, which has a periapsis altitude as low as 200 km, an apoapsis altitude near 15,000 km, and a closest approach to the surface varying from latitude 60 to about 70 N. The X-band tracking of MESSENGER and the laser altimetry are the primary data that will be used to measure the planetary shape and gravity field. The laser altimeter, which has an expected range of 1000 to 1200 km, is expected to provide significant data only over the northern hemisphere because of MESSENGER's eccentric orbit. For the southern hemisphere, radio occultation measurements obtained as the spacecraft passes behind the planet as seen from Earth and images obtained with the imaging system will be used to provide the long-wavelength shape of the planet. Gravity, derived from the tracking data, will also have greater resolution in the northern hemisphere, but full global models for both topography and gravity will be obtained at low harmonic order and degree. The limiting factor for both gravity and topography is expected to be knowledge of the spacecraft location. Present estimations are that in a combined tracking, altimetry, and occultation solution the spacecraft position uncertainty is likely to be of order 10 m. This accuracy should be adequate for establishing an initial geodetic coordinate system for Mercury that will enable positioning of imaged features on the surface, determination of the planet's obliquity, and detection of the librational motion of the planet about its axis.

Spacecraft-spacecraft very long baseline interferometry for planetary approach navigation

NASA Technical Reports Server (NTRS)

Edwards, Charles D., Jr.; Folkner, William M.; Border, James S.; Wood, Lincoln J.

1991-01-01

The study presents an error budget for Delta differential one-way range (Delta-DOR) measurements between two spacecraft. Such observations, made between a planetary orbiter (or lander) and another spacecraft approaching that planet, would provide a powerful target-relative angular tracking data type for approach navigation. Accuracies of about 5 nrad should be possible for a pair of X-band spacecraft incorporating 40-MHz DOR tone spacings, while accuracies approaching 1 nrad will be possible if the spacecraft incorporate Ka-band downlinks with DOR tone spacings of order 250 MHz. Operational advantages of this data type are discussed, and ground system requirements needed to enable S/C-S/C Delta-DOR observations are outlined. A covariance analysis is presented to examine the potential navigation improvement for this scenario. The results show factors of 2-3 improvement in spacecraft targeting over conventional Doppler, range, and quasar-relative VLBI, along with reduced sensitivity to ephemeris uncertainty and other systematic errors.

Alternative Attitude Commanding and Control for Precise Spacecraft Landing

NASA Technical Reports Server (NTRS)

Singh, Gurkirpal

2004-01-01

A report proposes an alternative method of control for precision landing on a remote planet. In the traditional method, the attitude of a spacecraft is required to track a commanded translational acceleration vector, which is generated at each time step by solving a two-point boundary value problem. No requirement of continuity is imposed on the acceleration. The translational acceleration does not necessarily vary smoothly. Tracking of a non-smooth acceleration causes the vehicle attitude to exhibit undesirable transients and poor pointing stability behavior. In the alternative method, the two-point boundary value problem is not solved at each time step. A smooth reference position profile is computed. The profile is recomputed only when the control errors get sufficiently large. The nominal attitude is still required to track the smooth reference acceleration command. A steering logic is proposed that controls the position and velocity errors about the reference profile by perturbing the attitude slightly about the nominal attitude. The overall pointing behavior is therefore smooth, greatly reducing the degree of pointing instability.

A tracking polarimeter for measuring solar and ionospheric Faraday rotation of signals from deep space probes

NASA Technical Reports Server (NTRS)

Ohlson, J. E.; Levy, G. S.; Stelzried, C. T.

1974-01-01

A tracking polarimeter implemented on the 64-m NASA/JPL paraboloid antenna at Goldstone, Calif., is described. Its performance is analyzed and compared with measurements. The system was developed to measure Faraday rotation in the solar corona of the telemetry carrier from the Pioneer VI spacecraft as it was occulted by the sun. It also measures rotation in the earth's ionosphere and is an accurate method of determining spacecraft orientation. The new feature of this system is its use of a pair of quarter-wave plates to allow the synthesis of a rotating feed system, while requiring the rotation of only a single section of waveguide. Since the polarization sensing is done at RF and the receiver operates essentially as a null detector, the system's accuracy is superior to other polarization tracking schemes. In addition, the antenna size and maser preamplifier provide unsurpassed sensitivity. The associated instrumentation used in the Pioneer VI experiment is also described.

Global tracking of space debris via CPHD and consensus

NASA Astrophysics Data System (ADS)

Wei, Baishen; Nener, Brett; Liu, Weifeng; Ma, Liang

2017-05-01

Space debris tracking is of great importance for safe operation of spacecraft. This paper presents an algorithm that achieves global tracking of space debris with a multi-sensor network. The sensor network has unknown and possibly time-varying topology. A consensus algorithm is used to effectively counteract the effects of data incest. Gaussian Mixture-Cardinalized Probability Hypothesis Density (GM-CPHD) filtering is used to estimate the state of the space debris. As an example of the method, 45 clusters of sensors are used to achieve global tracking. The performance of the proposed approach is demonstrated by simulation experiments.

A review of GPS-based tracking techniques for TDRS orbit determination

NASA Technical Reports Server (NTRS)

Haines, B. J.; Lichten, S. M.; Malla, R. P.; Wu, S.-C.

1993-01-01

This article evaluates two fundamentally different approaches to the Tracking and Data Relay Satellite (TDRS) orbit determination utilizing Global Positioning System (GPS) technology and GPS-related techniques. In the first, a GPS flight receiver is deployed on the TDRS. The TDRS ephemerides are determined using direct ranging to the GPS spacecraft, and no ground network is required. In the second approach, the TDRS's broadcast a suitable beacon signal, permitting the simultaneous tracking of GPS and Tracking and Data Relay Satellite System satellites by ground receivers. Both strategies can be designed to meet future operational requirements for TDRS-II orbit determination.

Systematic Examination of Stardust Bulbous Track Wall Materials

NASA Technical Reports Server (NTRS)

Nakamura-Messenger, K.; Clemett, S. J.; Nguyen, A. N.; Berger, E. L.; Keller, L. P.; Messenger, S.

2013-01-01

Analyses of Comet Wild-2 samples returned by NASA's Stardust spacecraft have focused primarily on terminal particles (TPs) or well-preserved fine-grained materials along the track walls [1,2]. However much of the collected material was melted and mixed intimately with the aerogel by the hypervelocity impact [3,4]. We are performing systematic examinations of entire Stardust tracks to establish the mineralogy and origins of all comet Wild 2 components [7,8]. This report focuses on coordinated analyses of indigenous crystalline and amorphous/melt cometary materials along the aerogel track walls, their interaction with aerogel during collection and comparisons with their TPs.

TDRS-M: Spacecraft Pre-Media Event "Clean Shots"

NASA Image and Video Library

2017-07-13

Inside the Astrotech facility in Titusville, Florida, NASA's Tracking and Data Relay Satellite, TDRS-M, is undergoing final checkouts prior to encapsulation in its payload fairing. TDRS-M is the latest spacecraft destined for the agency's constellation of communications satellites that allows nearly continuous contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. Liftoff atop a United Launch Alliance Atlas V rocket is scheduled to take place from Space Launch Complex 41 at Cape Canaveral Air Force Station at 9:02 a.m. EDT Aug. 3, 2017.

Major technological innovations introduced in the large antennas of the Deep Space Network

NASA Technical Reports Server (NTRS)

Imbriale, W. A.

2002-01-01

The NASA Deep Space Network (DSN) is the largest and most sensitive scientific, telecommunications and radio navigation network in the world. Its principal responsibilities are to provide communications, tracking, and science services to most of the world's spacecraft that travel beyond low Earth orbit. The network consists of three Deep Space Communications Complexes. Each of the three complexes consists of multiple large antennas equipped with ultra sensitive receiving systems. A centralized Signal Processing Center (SPC) remotely controls the antennas, generates and transmits spacecraft commands, and receives and processes the spacecraft telemetry.

TDRS-M Spacecraft Lift & Mate

NASA Image and Video Library

2017-08-09

A crane is used to lift the payload fairing containing NASA's Tracking and Data Relay Satellite (TDRS-M) at the Vertical Integration Facility at Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. TDRS-M will be stacked atop the United Launch Alliance Atlas V Centaur upper stage. TDRS-M will be the latest spacecraft destined for the agency's constellation of communications satellites that allows nearly continuous contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. Liftoff atop the ULA Atlas V rocket is scheduled for Aug. 18, 2017.

KSC-02pd1578

NASA Image and Video Library

2002-10-18

KENNEDY SPACE CENTER, FLA. - The TDRS-J spacecraft, enclosed in a container, is transported past the Vehicle Assembly Building on its way to the Spacecraft Assembly and Encapsulation Facility-2 (SAEF-2) for processing. The Tracking and Data Relay Satellite System is the primary source of space-to-ground voice, data and telemetry for the Space Shuttle. It also provides communications with the International Space Station and scientific spacecraft in low-earth orbit such as the Hubble Space Telescope, and launch support for some expendable vehicles. This new advanced series of satellites will extend the availability of TDRS communications services until approximately 2017.

Expedition 55 Soyuz Docking

NASA Image and Video Library

2018-03-23

Icons for the International Space Station and Soyuz MS-08 spacecraft are seen on a tracking map on a screen in the Moscow Mission Control Center as the spacecraft approaches for docking, Friday, March 23, 2018 in Korolev, Russia. The Soyuz MS-08 spacecraft carrying Expedition 55-56 crewmembers Oleg Artemyev of Roscosmos and Ricky Arnold and Drew Feustel of NASA docked at 3:40 p.m. Eastern time (10:40 p.m. Moscow time) on March 23 and joined Expedition 55 Commander Anton Shkaplerov of Roscosmos, Scott Tingle of NASA, and Norishige Kanai of the Japan Aerospace Exploration Agency (JAXA). Photo Credit: (NASA/Joel Kowsky)

Graphical techniques to assist in pointing and control studies of orbiting spacecraft

NASA Technical Reports Server (NTRS)

Howell, L. W.; Ruf, J. H.

1986-01-01

Computer generated graphics are developed to assist in the modeling and assessment of pointing and control systems of orbiting spacecraft. Three-dimensional diagrams are constructed of the Earth and of geometrical models which resemble the spacecraft of interest. Orbital positioning of the spacecraft model relative to the Earth and the orbital ground track are then displayed. A star data base is also available which may be used for telescope pointing and star tracker field-of-views to visually assist in spacecraft pointing and control studies. A geometrical model of the Hubble Space Telescope (HST) is constructed and placed in Earth orbit to demonstrate the use of these programs. Simulated star patterns are then displayed corresponding to the primary mirror's FOV and the telescope's star trackers for various telescope orientations with respect to the celestial sphere.

Dust Devil Tracks

NASA Image and Video Library

2017-03-06

This image captured by NASA 2001 Mars Odyssey spacecraft shows dust devil tracks in Aonia Terra. As the dust devil moves along the surface it scours the dust and fine materials away, revealing the darker rocky surface below the dust. Orbit Number: 66962 Latitude: -68.8221 Longitude: 241.346 Instrument: VIS Captured: 2017-01-17 13:13 http://photojournal.jpl.nasa.gov/catalog/PIA21501

Experiments study on attitude coupling control method for flexible spacecraft

NASA Astrophysics Data System (ADS)

Wang, Jie; Li, Dongxu

2018-06-01

High pointing accuracy and stabilization are significant for spacecrafts to carry out Earth observing, laser communication and space exploration missions. However, when a spacecraft undergoes large angle maneuver, the excited elastic oscillation of flexible appendages, for instance, solar wing and onboard antenna, would downgrade the performance of the spacecraft platform. This paper proposes a coupling control method, which synthesizes the adaptive sliding mode controller and the positive position feedback (PPF) controller, to control the attitude and suppress the elastic vibration simultaneously. Because of its prominent performance for attitude tracking and stabilization, the proposed method is capable of slewing the flexible spacecraft with a large angle. Also, the method is robust to parametric uncertainties of the spacecraft model. Numerical simulations are carried out with a hub-plate system which undergoes a single-axis attitude maneuver. An attitude control testbed for the flexible spacecraft is established and experiments are conducted to validate the coupling control method. Both numerical and experimental results demonstrate that the method discussed above can effectively decrease the stabilization time and improve the attitude accuracy of the flexible spacecraft.

The Gravity Field of Mercury After the Messenger Low-Altitude Campaign

NASA Technical Reports Server (NTRS)

Mazarico, Erwan; Genova, Antonio; Goossens, Sander; Lemoine, Frank G.; Smith, David E.; Zuber, Maria T.; Neumann, Gary A.; Solomon, Sean C.

2015-01-01

The final year of the MESSENGER mission was designed to take advantage of the remaining propellant onboard to provide a series of lowaltitude observation campaigns and acquire novel scientific data about the innermost planet. The lower periapsis altitude greatly enhances the sensitivity to the short-wavelength gravity field, but only when the spacecraft is in view of Earth. After more than 3 years in orbit around Mercury, the MESSENGER spacecraft was tracked for the first time below 200-km altitude on 5 May 2014 by the NASA Deep Space Network (DSN). Between August and October, periapsis passages down to 25-km altitude were routinely tracked. These periods considerably improved the quality of the data coverage. Before the end of its mission, MESSENGER will fly at very low altitudes for extended periods of time. Given the orbital geometry, however the periapses will not be visible from Earth and so no new tracking data will be available for altitudes lower than 75 km. Nevertheless, the continuous tracking of MESSENGER in the northern hemisphere will help improve the uniformity of the spatial coverage at altitudes lower than 150 km, which will further improve the overall quality of the Mercury gravity field.

ASTRONAUT COOPER, GORDON - PRELAUNCH MERCURY-ATLAS (MA)-9 - "FAITH 7" - INSERTION - CAPE CANAVERAL, FL

NASA Image and Video Library

1963-05-14

S63-06259 (14 May 1963) --- Astronaut L. Gordon Cooper Jr., prime pilot for the Mercury-Atlas 9 (MA-9) mission, is assisted into his "Faith 7" Mercury spacecraft early morning on May 14, 1963. Cooper remained in the spacecraft for approximately five hours and then climbed out again as the mission was delayed because of trouble at a tracking station. Photo credit: NASA

The Voyager Spacecraft. [Jupiter-Saturn mission investigations

NASA Technical Reports Server (NTRS)

1979-01-01

The configuration of the Voyager spacecraft is described as well as the subsystems for power, temperature control, attitude control, and propulsion. Major features of Jupiter and Saturn including their atmospheres, surfaces, and natural satellites are discussed. The 13 onboard experiments and their scientific objectives are explained. Other aspects covered include tracking, data acquisition, and the mission control and computing center. Members of the Voyager team and subcontractors are listed.

System Identification and Automatic Mass Balancing of Ground-Based Three-Axis Spacecraft Simulator

DTIC Science & Technology

2006-08-01

commanded torque to move away from these singularity points. The introduction of this error may not degrade the performance for large slew angle ...trajectory has been generated and quaternion feedback control has been implemented for reference trajectory tracking. The testbed was reasonably well...System Identification and Automatic Mass Balancing of Ground-Based Three-Axis Spacecraft Simulator Jae-Jun Kim∗ and Brij N. Agrawal † Department of

Observed bulk properties of the Mars moon Phobos

NASA Astrophysics Data System (ADS)

Pätzold, M.; Andert, T. P.; Jacobson, R.; Rosenblatt, P.; Dehant, V.

2013-09-01

The mass of the Mars moon Phobos has been determined by spacecraft close flybys, by solving for the Martian gravity field and by the analysis of secular orbit perturbations. The absolute value and accuracy is sensitive on the actuality of the Phobos ephemeris, the accuracy of the spacecraft orbit, other perturbing forces acting on the spacecraft and the resolution of the Martian gravity field besides the measurement accuracy of the radio tracking data. The mass value and its error improved from spacecraft mission to mission or from the modern analysis of "old" tracking data but none of these values can claim to be the final truth. The mass value seems to settle within the range of GMPh = (7.11 +/- 0.09)·10-4 km3s-2 (3s) which covers almost all mass values from close flybys and "distant" encounters. Using the volume value determined from MEX HRSC imaging, the bulk density is (1873 +/- 31) kg/m3, a low value which suggests that Phobos is either highly porous, is composed partially of light material or both. In view of theories of the Phobos' origin, one possibility is that Phobos is not a captured asteroid but accreted from a debris disk in Mars orbit as a second generation solar system object.

Analytical solutions to optimal underactuated spacecraft formation reconfiguration

NASA Astrophysics Data System (ADS)

Huang, Xu; Yan, Ye; Zhou, Yang

2015-11-01

Underactuated systems can generally be defined as systems with fewer number of control inputs than that of the degrees of freedom to be controlled. In this paper, analytical solutions to optimal underactuated spacecraft formation reconfiguration without either the radial or the in-track control are derived. By using a linear dynamical model of underactuated spacecraft formation in circular orbits, controllability analysis is conducted for either underactuated case. Indirect optimization methods based on the minimum principle are then introduced to generate analytical solutions to optimal open-loop underactuated reconfiguration problems. Both fixed and free final conditions constraints are considered for either underactuated case and comparisons between these two final conditions indicate that the optimal control strategies with free final conditions require less control efforts than those with the fixed ones. Meanwhile, closed-loop adaptive sliding mode controllers for both underactuated cases are designed to guarantee optimal trajectory tracking in the presence of unmatched external perturbations, linearization errors, and system uncertainties. The adaptation laws are designed via a Lyapunov-based method to ensure the overall stability of the closed-loop system. The explicit expressions of the terminal convergent regions of each system states have also been obtained. Numerical simulations demonstrate the validity and feasibility of the proposed open-loop and closed-loop control schemes for optimal underactuated spacecraft formation reconfiguration in circular orbits.

Exchange of Standardized Flight Dynamics Data

NASA Technical Reports Server (NTRS)

Martin-Mur, Tomas J.; Berry, David; Flores-Amaya, Felipe; Folliard, J.; Kiehling, R.; Ogawa, M.; Pallaschke, S.

2004-01-01

Spacecraft operations require the knowledge of the vehicle trajectory and attitude and also that of other spacecraft or natural bodies. This knowledge is normally provided by the Flight Dynamics teams of the different space organizations and, as very often spacecraft operations involve more than one organization, this information needs to be exchanged between Agencies. This is why the Navigation Working Group within the CCSDS (Consultative Committee for Space Data Systems), has been instituted with the task of establishing standards for the exchange of Flight Dynamics data. This exchange encompasses trajectory data, attitude data, and tracking data. The Navigation Working Group includes regular members and observers representing the participating Space Agencies. Currently the group includes representatives from CNES, DLR, ESA, NASA and JAXA. This Working Group meets twice per year in order to devise standardized language, methods, and formats for the description and exchange of Navigation data. Early versions of some of these standards have been used to support mutual tracking of ESA and NASA interplanetary spacecraft, especially during the arrival of the 2003 missions to Mars. This paper provides a summary of the activities carried out by the group, briefly outlines the current and envisioned standards, describes the tests and operational activities that have been performed using the standards, and lists and discusses the lessons learned from these activities.

TDRS-L Pre-Launch Press Conference

NASA Image and Video Library

2014-01-21

CAPE CANAVERAL, Fla. –During a news conference at NASA's Kennedy Space Center in Florida, agency and contractor officials discussed preparations for the launch of NASA's Tracking and Data Relay Satellite, or TDRS-L, spacecraft. Participating in the briefing, from the left, are Badri Younes, deputy associate administrator, Space Communications and Navigation SCaN NASA Human Exploration and Operations Mission Directorate at NASA Headquarters in Washington D.C., Tim Dunn, NASA launch director at Kennedy, Vernon Thorp, program manager for NASA Missions with United Launch Alliance in Denver, Colo., Jeffrey Gramling, NASA's TDRS-L project manager at the Goddard Space Flight Center in Greenbelt, Md., Andy Kopito, Civil Space Programs director for Boeing Space & Intelligence Systems in El Segundo, Calif., and Clay Flinn, launch weather officer for the 45th Weather Squadron at Cape Canaveral Air Force Station, Fla. The TDRS-L spacecraft is the second of three new satellites designed to ensure vital operational continuity for NASA by expanding the lifespan of the Tracking and Data Relay Satellite System TDRSS fleet, which consists of eight satellites in geosynchronous orbit. The spacecraft provide tracking, telemetry, command and high bandwidth data return services for numerous science and human exploration missions orbiting Earth. These include NASA's Hubble Space Telescope and the International Space Station. TDRS-L has a high-performance solar panel designed for more spacecraft power to meet the growing S-band communications requirements. TDRSS is one of NASA Space Communication and Navigation’s SCaN three networks providing space communications to NASA’s missions. For more information more about TDRS-L, visit: http://www.nasa.gov/tdrs To learn more about SCaN, visit: www.nasa.gov/scan Photo credit: NASA/Frankie Martin

TDRS-L Pre-Launch Press Conference

NASA Image and Video Library

2014-01-21

CAPE CANAVERAL, Fla. –During a news conference at NASA's Kennedy Space Center in Florida, agency and contractor officials discussed preparations for the launch of NASA's Tracking and Data Relay Satellite, or TDRS-L, spacecraft. Participating in the briefing, from the left, are George Diller of NASA Public Affairs, Badri Younes, deputy associate administrator, Space Communications and Navigation SCaN NASA Human Exploration and Operations Mission Directorate at NASA Headquarters in Washington D.C., Tim Dunn, NASA launch director at Kennedy, Vernon Thorp, program manager for NASA Missions with United Launch Alliance in Denver, Colo., Jeffrey Gramling, NASA's TDRS-L project manager at the Goddard Space Flight Center in Greenbelt, Md., Andy Kopito, Civil Space Programs director for Boeing Space & Intelligence Systems in El Segundo, Calif., and Clay Flinn, launch weather officer for the 45th Weather Squadron at Cape Canaveral Air Force Station, Fla. The TDRS-L spacecraft is the second of three new satellites designed to ensure vital operational continuity for NASA by expanding the lifespan of the Tracking and Data Relay Satellite System TDRSS fleet, which consists of eight satellites in geosynchronous orbit. The spacecraft provide tracking, telemetry, command and high bandwidth data return services for numerous science and human exploration missions orbiting Earth. These include NASA's Hubble Space Telescope and the International Space Station. TDRS-L has a high-performance solar panel designed for more spacecraft power to meet the growing S-band communications requirements. TDRSS is one of NASA Space Communication and Navigation’s SCaN three networks providing space communications to NASA’s missions. For more information more about TDRS-L, visit: http://www.nasa.gov/tdrs To learn more about SCaN, visit: www.nasa.gov/scan Photo credit: NASA/Frankie Martin

The gravity field and orientation of Mercury after the MESSENGER mission

NASA Astrophysics Data System (ADS)

Mazarico, E.; Genova, A.; Goossens, S. J.; Lemoine, F. G.; Neumann, G. A.; Zuber, M. T.; Smith, D. E.; Solomon, S. C.

2015-12-01

After more than four years in orbit about Mercury, the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft impacted the planet's surface north of Shakespeare crater (54.44° N, 210.12° E,) on 30 April 2015. One of the main goals of the mission was to determine the gravity field of Mercury in order to learn about Mercury's interior. Together with ground-based radar measurements of the obliquity and forced librations, MESSENGER-derived gravity models helped revise models of Mercury's interior. Nevertheless, the refinement of Mercury's orientation with the latest data from MESSENGER can further improve the interior modeling of the planet. The last eight months of the mission provided a special opportunity to conduct low-altitude measurements, with extensive radio tracking coverage below 200 km altitude north of ~30°N. MESSENGER's Mercury Laser Altimeter (MLA) mapped the topography of Mercury's northern hemisphere with a sub-meter vertical precision, an along-track sampling of ~500 m, and a longitudinal resolution (~0.1°) limited by the number of spacecraft orbits (~4,000). The combination of gravity and topography helps determine crustal thickness and interior properties. Altimetric ranges provide geodetic constraints to improve the spacecraft orbit determination, and thus the gravity field model. In particular, whereas the MESSENGER spacecraft was not tracked at each periapsis passage, MLA operated nearly continuously (outside of thermally challenging periods). From an analysis of the entire radiometric and altimetric datasets acquired by MESSENGER, a new gravity field to degree and order 100 has been obtained, resolving features down to ~75 km horizontal scale. The altimetric data help reduce the uncertainties in the determination of the pole position. A reanalysis of the Mercury flybys also constrains the spin rate over the longest available time span.

TDRS-L Tribute Decal to Arthur "Skip" Mackey, Jr.

NASA Image and Video Library

2014-01-22

CAPE CANAVERAL, Fla. – This memorial message was added to the Atlas V rocket for NASA's Tracking and Data Relay Satellite, or TDRS-L, spacecraft being prepared for launch from Cape Canaveral Air Force Station's Launch Complex 41. Arthur J. "Skip" Mackey Jr. was the “Voice of NASA” during the 1960s, 1970s and early 1980s for flight commentary after liftoff for expendable vehicles launched from Cape Canaveral. Mackey served as branch chief for Telemetry and Communications at Hangar AE in the agency’s Expendable Launch Vehicle Program and then the Launch Services Program for 39 years. He died in Fort Lauderdale, Fla., on Nov. 19, 2013. The TDRS-L spacecraft is the second of three new satellites designed to ensure vital operational continuity for NASA by expanding the lifespan of the Tracking and Data Relay Satellite System TDRSS fleet, which consists of eight satellites in geosynchronous orbit. The spacecraft provide tracking, telemetry, command and high bandwidth data return services for numerous science and human exploration missions orbiting Earth. These include NASA's Hubble Space Telescope and the International Space Station. TDRS-L has a high-performance solar panel designed for more spacecraft power to meet the growing S-band communications requirements. TDRSS is one of NASA Space Communication and Navigation’s SCaN three networks providing space communications to NASA’s missions. For more information more about TDRS-L, visit: http://www.nasa.gov/tdrs To learn more about SCaN, visit: www.nasa.gov/scan For more on "Skip" Mackey go to: http://www.nasa.gov/content/skip-mackey-remembered-by-colleagues-as-voice-of-nasa/ Image credit: United Launch Alliance

The Mars Observer Ka-band link experiment

NASA Technical Reports Server (NTRS)

Rebold, T. A.; Kwok, A.; Wood, G. E.; Butman, S.

1994-01-01

The Ka-Band Link Experiment was the first demonstration of a deep-space communications link in the 32- to 35-GHz band (Ka-band). It was carried out using the Mars Observer spacecraft while the spacecraft was in the cruise phase of its mission and using a 34-meter beam-waveguide research and development antenna at the Goldstone complex of the DSN. The DSN has been investigating the performance benefits of a shift from X-band (8.4 GHz) to Ka-band (32 GHz) for deep-space communications. The fourfold increase in frequency is expected to offer a factor of 3 to 10 improvement (5 to 10 dB) in signal strength for a given spacecraft transmitter power and antenna size. Until recently, the expected benefits were based on performance studies, with an eye to implementing such a link, but theory was transformed to reality when a 33.7-GHz Ka-band signal was received from the spacecraft by DSS 13. This article describes the design and implementation of the Ka-Band Link Experiment from the spacecraft to the DSS-13 system, as well as results from the Ka-band telemetry demonstration, ranging demonstration, and long-term tracking experiment. Finally, a preliminary analysis of comparative X- and Ka-band tracking results is included. These results show a 4- to 7-dB advantage for Ka-band using the system at DSS 13, assuming such obstacles as antenna pointing loss and power conversion loss are overcome.

Computer models of the spacecraft wake

NASA Technical Reports Server (NTRS)

Rubin, A. G.; Heinemann, M.; Tautz, M.; Cooke, D.

1986-01-01

Until recently, computations of space plasma flow over a spacecraft have been unstable for ratios of spacecraft dimension to Debye length typical of the low Earth orbit environment. Calculations are presented of the spacecraft/environment interaction based on two computer codes, MACH and POLAR. MACH, an inside-out particle tracking code, was developed for the purpose of validating the physics of POLAR in regimes where these are no comprehensive theoretical or experimental results. While the spacecraft which can be treated by MACH are restricted to simple geometries, the methodology is more fundamental than POLAR. MACH generates self-consistent solutions within the context of quasisteady Vlasov plasma flow and achieves Debye ratios previously unobtainable. POLAR uses a three-dimensional finite-element representation of the vehicle in a staggered mesh. The plasma sheath is modeled by outside-in particle tracking. Solutions for the plasma flow, wake and vehicle charging are obtained by Vlasov-Poisson iteration; charge stabilization techniques make the results virtually insensitive to the Debye ratio. POLAR reproduces the Laframboise static plasma solutions for sperical probes and fits the Makita-Kuriki probe data for spheres in a flowing plasma in regions where comparisons are valid. POLAR and MACH solutions for the particle and electrostatic potential structure of the wake of a charged disk in a low-altitude flow are shown for Mach numbers 4, 5, and 8. New features of the solutions include ion focussing in the wake and a definitive determination of the sheath edge in the wake which shows that the sheath is not an equipotential.

An improved gravity model for Mars: Goddard Mars Model 1

NASA Technical Reports Server (NTRS)

Smith, D. E.; Lerch, F. J.; Nerem, R. S.; Zuber, M. T.; Patel, G. B.; Fricke, S. K.; Lemoine, F. G.

1993-01-01

Doppler tracking data of three orbiting spacecraft have been reanalyzed to develop a new gravitational field model for the planet Mars, Goddard Mars Model 1 (GMM-1). This model employs nearly all available data, consisting of approximately 1100 days of S band tracking data collected by NASA's Deep Space Network from the Mariner 9 and Viking 1 and Viking 2 spacecraft, in seven different orbits, between 1971 and 1979. GMM-1 is complete to spherical harmonic degree and order 50, which corresponds to a half-wavelength spatial resolution of 200-300 km where the data permit. GMM-1 represents satellite orbits with considerably better accuracy than previous Mars gravity models and shows greater resolution of identifiable geological structures. The notable improvement in GMM-1 over previous models is a consequence of several factors: improved computational capabilities, the use of otpimum weighting and least squares collocation solution techniques which stabilized the behavior of the solution at high degree and order, and the use of longer satellite arcs than employed in previous solutions that were made possible by improved force and measurement models. The inclusion of X band tracking data from the 379-km altitude, nnear-polar orbiting Mars Observer spacecraft should provide a significant improvement over GMM-1, particularly at high latitudes where current data poorly resolve the gravitational signature of the planet.

An improved gravity model for Mars: Goddard Mars Model-1 (GMM-1)

NASA Technical Reports Server (NTRS)

Smith, D. E.; Lerch, F. J.; Nerem, R. S.; Zuber, M. T.; Patel, G. B.; Fricke, S. K.; Lemoine, F. G.

1993-01-01

Doppler tracking data of three orbiting spacecraft have been reanalyzed to develop a new gravitational field model for the planet Mars, GMM-1 (Goddard Mars Model-1). This model employs nearly all available data, consisting of approximately 1100 days of S-bank tracking data collected by NASA's Deep Space Network from the Mariner 9, and Viking 1 and Viking 2 spacecraft, in seven different orbits, between 1971 and 1979. GMM-1 is complete to spherical harmonic degree and order 50, which corresponds to a half-wavelength spatial resolution of 200-300 km where the data permit. GMM-1 represents satellite orbits with considerably better accuracy than previous Mars gravity models and shows greater resolution of identifiable geological structures. The notable improvement in GMM-1 over previous models is a consequence of several factors: improved computational capabilities, the use of optimum weighting and least-squares collocation solution techniques which stabilized the behavior of the solution at high degree and order, and the use of longer satellite arcs than employed in previous solutions that were made possible by improved force and measurement models. The inclusion of X-band tracking data from the 379-km altitude, near-polar orbiting Mars Observer spacecraft should provide a significant improvement over GMM-1, particularly at high latitudes where current data poorly resolves the gravitational signature of the planet.

Data catalog series for space science and applications flight missions. Volume 4A: Descriptions of meteorological and terrestrial applications spacecraft and investigations

NASA Technical Reports Server (NTRS)

Ng, C. Y. (Editor); Sheu, Y. T. P. (Editor)

1985-01-01

The National Space Science Data Center (NSSDC) provides data from and information about space science and applications flight investigations in support of additional studies beyond those performed as the principal part of any flight mission. The Earth-orbiting spacecraft for investigations of the earth and its atmosphere is discussed. Geodetic tracking data are included in this category. The principal subject areas presented are meteorology and earth resources survey, and the spacecraft selection is made according to those subjects. All experiments on board the spacecraft are described. No attempt is made to reference investigations that are related to the above disciplines, but that are described in other volumes of this series.

SeaTrack: Ground station orbit prediction and planning software for sea-viewing satellites

NASA Technical Reports Server (NTRS)

Lambert, Kenneth S.; Gregg, Watson W.; Hoisington, Charles M.; Patt, Frederick S.

1993-01-01

An orbit prediction software package (Sea Track) was designed to assist High Resolution Picture Transmission (HRPT) stations in the acquisition of direct broadcast data from sea-viewing spacecraft. Such spacecraft will be common in the near future, with the launch of the Sea viewing Wide Field-of-view Sensor (SeaWiFS) in 1994, along with the continued Advanced Very High Resolution Radiometer (AVHRR) series on NOAA platforms. The Brouwer-Lyddane model was chosen for orbit prediction because it meets the needs of HRPT tracking accuracies, provided orbital elements can be obtained frequently (up to within 1 week). Sea Track requires elements from the U.S. Space Command (NORAD Two-Line Elements) for the satellite's initial position. Updated Two-Line Elements are routinely available from many electronic sources (some are listed in the Appendix). Sea Track is a menu-driven program that allows users to alter input and output formats. The propagation period is entered by a start date and end date with times in either Greenwich Mean Time (GMT) or local time. Antenna pointing information is provided in tabular form and includes azimuth/elevation pointing angles, sub-satellite longitude/latitude, acquisition of signal (AOS), loss of signal (LOS), pass orbit number, and other pertinent pointing information. One version of Sea Track (non-graphical) allows operation under DOS (for IBM-compatible personal computers) and UNIX (for Sun and Silicon Graphics workstations). A second, graphical, version displays orbit tracks, and azimuth-elevation for IBM-compatible PC's, but requires a VGA card and Microsoft FORTRAN.

Impact analysis of the transponder time delay on radio-tracking observables

NASA Astrophysics Data System (ADS)

Bertone, Stefano; Le Poncin-Lafitte, Christophe; Rosenblatt, Pascal; Lainey, Valéry; Marty, Jean-Charles; Angonin, Marie-Christine

2018-01-01

Accurate tracking of probes is one of the key points of space exploration. Range and Doppler techniques are the most commonly used. In this paper we analyze the impact of the transponder delay, i . e . the processing time between reception and re-emission of a two-way tracking link at the satellite, on tracking observables and on spacecraft orbits. We show that this term, only partially accounted for in the standard formulation of computed space observables, can actually be relevant for future missions with high nominal tracking accuracies or for the re-processing of old missions. We present several applications of our formulation to Earth flybys, the NASA GRAIL and the ESA BepiColombo missions.

The Telecommunications and Data Acquisition Report

NASA Technical Reports Server (NTRS)

Posner, E. C. (Editor)

1988-01-01

Deep Space Network and Systems topics addressed include: tracking and ground-base navigation; communications, spacecraft-ground; station control and system technology; capabilities for existing projects; and network upgrading and sustaining.

On the detection of a stochastic background of gravitational radiation by the Doppler tracking of spacecraft

NASA Technical Reports Server (NTRS)

Mashhoon, B.; Grishchuk, L. P.

1980-01-01

Consideration is given to the possibility of detection of an isotropic background gravitational radiation of a stochastic nature by the method of Doppler tracking of spacecraft. Attention is given in the geometrical optics limit, to the general formula for the frequency shift of an electromagnetic signal in the gravitational radiation field, and it is shown to be gauge independent. The propagation of a free electromagnetic wave in a gravitational radiation field is examined with the conclusion that no resonance phenomena can be expected. Finally, the 'Doppler noise' due to a stochastic background is evaluated, and it is shown to depend on the total energy density of the background and a parameter that is a characteristic of the radiation spectrum and the detection system used.

ORBSIM- ESTIMATING GEOPHYSICAL MODEL PARAMETERS FROM PLANETARY GRAVITY DATA

NASA Technical Reports Server (NTRS)

Sjogren, W. L.

1994-01-01

The ORBSIM program was developed for the accurate extraction of geophysical model parameters from Doppler radio tracking data acquired from orbiting planetary spacecraft. The model of the proposed planetary structure is used in a numerical integration of the spacecraft along simulated trajectories around the primary body. Using line of sight (LOS) Doppler residuals, ORBSIM applies fast and efficient modelling and optimization procedures which avoid the traditional complex dynamic reduction of data. ORBSIM produces quantitative geophysical results such as size, depth, and mass. ORBSIM has been used extensively to investigate topographic features on the Moon, Mars, and Venus. The program has proven particulary suitable for modelling gravitational anomalies and mascons. The basic observable for spacecraft-based gravity data is the Doppler frequency shift of a transponded radio signal. The time derivative of this signal carries information regarding the gravity field acting on the spacecraft in the LOS direction (the LOS direction being the path between the spacecraft and the receiving station, either Earth or another satellite). There are many dynamic factors taken into account: earth rotation, solar radiation, acceleration from planetary bodies, tracking station time and location adjustments, etc. The actual trajectories of the spacecraft are simulated using least squares fitted to conic motion. The theoretical Doppler readings from the simulated orbits are compared to actual Doppler observations and another least squares adjustment is made. ORBSIM has three modes of operation: trajectory simulation, optimization, and gravity modelling. In all cases, an initial gravity model of curved and/or flat disks, harmonics, and/or a force table are required input. ORBSIM is written in FORTRAN 77 for batch execution and has been implemented on a DEC VAX 11/780 computer operating under VMS. This program was released in 1985.

The STEREO Mission: A New Approach to Space Weather Research

NASA Technical Reports Server (NTRS)

Kaiser, michael L.

2006-01-01

With the launch of the twin STEREO spacecraft in July 2006, a new capability will exist for both real-time space weather predictions and for advances in space weather research. Whereas previous spacecraft monitors of the sun such as ACE and SOH0 have been essentially on the sun-Earth line, the STEREO spacecraft will be in 1 AU orbits around the sun on either side of Earth and will be viewing the solar activity from distinctly different vantage points. As seen from the sun, the two spacecraft will separate at a rate of 45 degrees per year, with Earth bisecting the angle. The instrument complement on the two spacecraft will consist of a package of optical instruments capable of imaging the sun in the visible and ultraviolet from essentially the surface to 1 AU and beyond, a radio burst receiver capable of tracking solar eruptive events from an altitude of 2-3 Rs to 1 AU, and a comprehensive set of fields and particles instruments capable of measuring in situ solar events such as interplanetary magnetic clouds. In addition to normal daily recorded data transmissions, each spacecraft is equipped with a real-time beacon that will provide 1 to 5 minute snapshots or averages of the data from the various instruments. This beacon data will be received by NOAA and NASA tracking stations and then relayed to the STEREO Science Center located at Goddard Space Flight Center in Maryland where the data will be processed and made available within a goal of 5 minutes of receipt on the ground. With STEREO's instrumentation and unique view geometry, we believe considerable improvement can be made in space weather prediction capability as well as improved understanding of the three dimensional structure of solar transient events.

An Overview of the Topography of Mars from the Mars Orbiter Laser Altimeter (MOLA)

NASA Technical Reports Server (NTRS)

Smith, David E.; Zuber, Maria T.

2000-01-01

The Mars Global Surveyor (MGS) spacecraft has now completed more than half of its one-Mars-year mission to globally map Mars. During the MGS elliptical and circular orbit mapping phases, the Mars Orbiter Laser Altimeter (MOLA), an instrument on the MGS payload, has collected over 300 million precise elevation measurements. MOLA measures the range from the MGS spacecraft to the Martian surface and to atmospheric reflections. Range is converted to topography through knowledge of the MGS spacecraft orbit. Ranges from MOLA have resulted in a precise global topographic map of Mars. The instrument has also provided measurements of the width of the backscattered optical pulse and of the 1064 nm reflectivity of the Martian surface and atmosphere. The range resolution of the MOLA instrument is 37.5 cm and the along-track resolution of MOLA ground shots is approx. 300 m; the across-track spacing depends on latitude and time in the mapping orbit. The best current topographic grid has a spatial resolution of approx. 1/16 deg and vertical accuracy of approx. one meter. Additional information is contained in the original extended abstract.

TDRS-L Media Day

NASA Image and Video Library

2014-01-03

TITUSVILLE, Fla. – Members of the news media are given an opportunity for an up-close look at the Tracking and Data Relay Satellite, or TDRS-L, spacecraft undergoing preflight processing inside the Astrotech payload processing facility in Titusville. TDRS-L is being prepared for encapsulation inside its payload fairing prior to being transported to Launch Complex 41 at Cape Canaveral Air Force Station. Journalists visited Astrotech as part of TDRS-L Media Day to conduct interviews and photograph the satellite that will be a part of the second of three next-generation spacecraft designed to ensure vital operational continuity for the NASA Space Network. It is scheduled to launch from Cape Canaveral's Space Launch Complex 41 atop an Atlas V rocket in January 2014. The current Tracking and Data Relay Satellite system consists of eight in-orbit satellites distributed to provide near continuous information relay contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. For more information, visit: http://www.nasa.gov/mission_pages/tdrs/home/index.html

A Large Array of Small Antennas to Support Future NASA Missions

NASA Astrophysics Data System (ADS)

Jones, D. L.; Weinreb, S.; Preston, R. A.

2001-01-01

A team of engineers and scientists at JPL is currently working on the design of an array of small radio antennas with a total collecting area up to twenty times that of the largest existing (70 m) DSN antennas. An array of this size would provide obvious advantages for high data rate telemetry reception and for spacecraft navigation. Among these advantages are an order-of-magnitude increase in sensitivity for telemetry downlink, flexible sub-arraying to track multiple spacecraft simultaneously, increased reliability through the use of large numbers of identical array elements, very accurate real-time angular spacecraft tracking, and a dramatic reduction in cost per unit area. NASA missions in many disciplines, including planetary science, would benefit from this increased DSN capability. The science return from planned missions could be increased, and opportunities for less expensive or completely new kinds of missions would be created. The DSN array would also bean immensely valuable instrument for radio astronomy. Indeed, it would be by far the most sensitive radio telescope in the world. Additional information is contained in the original extended abstract.

Stellar Gyroscope for Determining Attitude of a Spacecraft

NASA Technical Reports Server (NTRS)

Pain, Bedabrata; Hancock, Bruce; Liebe, Carl; Mellstrom, Jeffrey

2005-01-01

A paper introduces the concept of a stellar gyroscope, currently at an early stage of development, for determining the attitude or spin axis, and spin rate of a spacecraft. Like star trackers, which are commercially available, a stellar gyroscope would capture and process images of stars to determine the orientation of a spacecraft in celestial coordinates. Star trackers utilize chargecoupled devices as image detectors and are capable of tracking attitudes at spin rates of no more than a few degrees per second and update rates typically <5 Hz. In contrast, a stellar gyroscope would utilize an activepixel sensor as an image detector and would be capable of tracking attitude at a slew rate as high as 50 deg/s, with an update rate as high as 200 Hz. Moreover, a stellar gyroscope would be capable of measuring a slew rate up to 420 deg/s. Whereas a Sun sensor and a three-axis mechanical gyroscope are typically needed to complement a star tracker, a stellar gyroscope would function without them; consequently, the mass, power consumption, and mechanical complexity of an attitude-determination system could be reduced considerably.

Interplanetary Dust Observations by the Juno MAG Investigation

NASA Astrophysics Data System (ADS)

Jørgensen, John; Benn, Mathias; Denver, Troelz; Connerney, Jack; Jørgensen, Peter; Bolton, Scott; Brauer, Peter; Levin, Steven; Oliversen, Ronald

2017-04-01

The spin-stabilized and solar powered Juno spacecraft recently concluded a 5-year voyage through the solar system en route to Jupiter, arriving on July 4th, 2016. During the cruise phase from Earth to the Jovian system, the Magnetometer investigation (MAG) operated two magnetic field sensors and four co-located imaging systems designed to provide accurate attitude knowledge for the MAG sensors. One of these four imaging sensors - camera "D" of the Advanced Stellar Compass (ASC) - was operated in a mode designed to detect all luminous objects in its field of view, recording and characterizing those not found in the on-board star catalog. The capability to detect and track such objects ("non-stellar objects", or NSOs) provides a unique opportunity to sense and characterize interplanetary dust particles. The camera's detection threshold was set to MV9 to minimize false detections and discourage tracking of known objects. On-board filtering algorithms selected only those objects tracked through more than 5 consecutive images and moving with an apparent angular rate between 15"/s and 10,000"/s. The coordinates (RA, DEC), intensity, and apparent velocity of such objects were stored for eventual downlink. Direct detection of proximate dust particles is precluded by their large (10-30 km/s) relative velocity and extreme angular rates, but their presence may be inferred using the collecting area of Juno's large ( 55m2) solar arrays. Dust particles impact the spacecraft at high velocity, creating an expanding plasma cloud and ejecta with modest (few m/s) velocities. These excavated particles are revealed in reflected sunlight and tracked moving away from the spacecraft from the point of impact. Application of this novel detection method during Juno's traversal of the solar system provides new information on the distribution of interplanetary (µm-sized) dust.

Slice of Comet Dust

NASA Image and Video Library

2006-02-21

This image illustrates one of several ways scientists have begun extracting comet particles from NASAa Stardust spacecraft collector. First, a particle and its track are cut out of the collector material, called aerogel.

Venus Gravity: 180th Degree and Order Model

NASA Technical Reports Server (NTRS)

Konopliv, A. S.; Banerdt, W. B.; Sjogren, W. L.

1998-01-01

The Megallan Doppler radiometric tracking data provides unprecedented precision for spacecraft based gravity measurements with the maximum resolution approaching spherical harmonic degree and order 180 in selected equatorial regions.

Communicating with Voyager

NASA Technical Reports Server (NTRS)

Dumas, Larry N.; Hornstein, Robert M.

1990-01-01

The Deep Space Network for receiving Voyager 2 data is discussed. The functions of the earth-Voyager radio link are examined, including radiometrics, transmission of commands to the spacecraft, radio sciences, and the transmission of telemetry from the spacecraft to earth. The use of ranging, Doppler, and VLBI measurements to maintain position and velocity data on Voyager 2 is described. Emphasis is placed on the international tracking network for obtaining Voyager 2 data on Neptune and Triton.

Lighting Automation - Flying an Earthlike Habit Project

NASA Technical Reports Server (NTRS)

Falker, Jay; Howard, Ricky; Culbert, Christopher; Clark, Toni Anne; Kolomenski, Andrei

2017-01-01

Our proposal will enable the development of automated spacecraft habitats for long duration missions. Majority of spacecraft lighting systems employ lamps or zone specific switches and dimmers. Automation is not in the "picture". If we are to build long duration environments, which provide earth-like habitats, minimize crew time, and optimize spacecraft power reserves, innovation in lighting automation is a must. To transform how spacecraft lighting environments are automated, we will provide performance data on a standard lighting communication protocol. We will investigate utilization and application of an industry accepted lighting control protocol, DMX512. We will demonstrate how lighting automation can conserve power, assist with lighting countermeasures, and utilize spatial body tracking. By using DMX512 we will prove the "wheel" does not need to be reinvented in terms of smart lighting and future spacecraft can use a standard lighting protocol to produce an effective, optimized and potentially earthlike habitat.

Ship Tracks

NASA Image and Video Library

2017-12-08

Ship tracks above the northern Pacific Ocean. NASA image captured July 3, 2010. Satellite: Aqua NASA/GSFC/Jeff Schmaltz/MODIS Land Rapid Response Team To learn more about MODIS go to: rapidfire.sci.gsfc.nasa.gov/gallery/?latest To learn more about ship tracks go to: visibleearth.nasa.gov/view_rec.php?id=2370 To watch a video on ship tracks go to: www.youtube.com/watch?v=Vsri2sOAjWo&feature=player_em...! NASA Goddard Space Flight Center is home to the nation's largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

The Telecommunications and Data Acquisition Report

NASA Technical Reports Server (NTRS)

Posner, E. C. (Editor)

1987-01-01

Topics addressed include: tracking and ground-based navigation; communications, spacecraft-ground; station control and system technology; capabilities for existing projects; network upgrade and sustaining; mission interface and support; and Ka-band capabilities.

KSC-2012-6547

NASA Image and Video Library

2012-12-19

TITUSVILLE, Fla. - Technicians unpack the Tracking and Data Relay Satellite, TDRS-K, after arrival at the Astrotech payload processing facility in Titusville, Fla. near NASA’s Kennedy Space Center. Launch of the TDRS-K on the Atlas V rocket is planned for January 29, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2012-6548

NASA Image and Video Library

2012-12-19

TITUSVILLE, Fla. - Technicians unpack the Tracking and Data Relay Satellite, TDRS-K, after arrival at the Astrotech payload processing facility in Titusville, Fla. near NASA’s Kennedy Space Center. Launch of the TDRS-K on the Atlas V rocket is planned for January 29, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1086

NASA Image and Video Library

2013-01-16

TITUSVILLE, Fla. – Technicians move one half of the payload fairing into place over NASA's Tracking and Data Relay Satellite, TDRS-K, inside the Astrotech payload processing facility in Titusville, Fla., near NASA’s Kennedy Space Center. Launch of the TDRS-K on a United Launch Alliance Atlas V rocket is planned for January 29, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. Photo credit: NASA/Frankie Martin

KSC-2012-6540

NASA Image and Video Library

2012-12-19

TITUSVILLE, Fla. - A truck transporting the Tracking and Data Relay Satellite, TDRS-K, arrives at the Astrotech payload processing facility in Titusville, Fla. near NASA’s Kennedy Space Center. Launch of the TDRS-K on the Atlas V rocket is planned for January 29, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1054

NASA Image and Video Library

2013-01-11

TITUSVILLE, Fla. - In the Astrotech payload processing facility in Titusville, Fla. near NASA’s Kennedy Space Center, a Boeing technician checks out the Tracking and Data Relay Satellite, TDRS-K. Launch of the TDRS-K on the Atlas V rocket is planned for January 29, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Jim Grossmann

Software for Tracking Costs of Mars Projects

NASA Technical Reports Server (NTRS)

Wong, Alvin; Warfield, Keith

2003-01-01

The Mars Cost Tracking Model is a computer program that administers a system set up for tracking the costs of future NASA projects that pertain to Mars. Previously, no such tracking system existed, and documentation was written in a variety of formats and scattered in various places. It was difficult to justify costs or even track the history of costs of a spacecraft mission to Mars. The present software enables users to maintain all cost-model definitions, documentation, and justifications of cost estimates in one computer system that is accessible via the Internet. The software provides sign-off safeguards to ensure the reliability of information entered into the system. This system may eventually be used to track the costs of projects other than only those that pertain to Mars.

Communication analysis for the expendable explorer spacecraft

NASA Technical Reports Server (NTRS)

1990-01-01

This report provides the results of communication analysis for the baseline and enhanced performance spacecraft designs proposed for Expendable Explorer Spacecraft (EES) series of missions. Five classes of orbits (Geosynchronous, Circular-28 degree inclination, Polar-90 degree inclination, Sunsynchronous-97 degree inclination, Molniya orbit) and a set of candidate instrument payloads provided by the ESS Study Manager were used to formulate the basis for the ESS Communications Study. The study was performed to assess the feasibility of using Space Network or ground stations for supporting the communications, tracking and data handling of the candidate instruments that are proposed to be launched into the desired orbit.

Mariner-Venus 1967

NASA Technical Reports Server (NTRS)

1971-01-01

Detailed information on the spacecraft performance, mission operations, and tracking and data acquisition is presented for the Mariner Venus 1967 and Mariner Venus 1967 extension projects. Scientific and engineering results and conclusions are discussed, and include the scientific mission, encounter with Venus, observations near Earth, and cruise phase of the mission. Flight path analysis, spacecraft subsystems, and mission-related hardware and computer program development are covered. The scientific experiments carried by Mariner 5 were ultraviolet photometer, solar plasma probe, helium magnetometer, trapped radiation detector, S-band radio occultation, dual-frequency radio propagation, and celestial mechanics. The engineering experience gained by converting a space Mariner Mars 1964 spacecraft into one flown to Venus is also described.

TDRS-M Spacecraft Lift to Transport Vehicle

NASA Image and Video Library

2017-08-08

Inside the Astrotech facility in Titusville, Florida, the payload fairing for NASA's Tracking and Data Relay Satellite, TDRS-M, is lifted and placed into position on the transport vehicle, in preparation for transport to Launch Complex 41. TDRS-M is the latest spacecraft destined for the agency's constellation of communications satellites that allows nearly continuous contact with orbiting spacecraft ranging from the International Space Station and Hubble Space Telescope to the array of scientific observatories. Liftoff atop a United Launch Alliance Atlas V rocket is scheduled to take place from Space Launch Complex 41 at Cape Canaveral Air Force Station at 8:03 a.m. EDT Aug. 18, 2017.

The spacecraft encounters of Comet Halley

NASA Technical Reports Server (NTRS)

Asoka Mendis, D.; Tsurutani, Bruce T.

1986-01-01

The characteristics of the Comet Halley spacecraft 'fleet' (VEGA 1 and VEGA 2, Giotto, Suisei, and Sakigake) are presented. The major aims of these missions were (1) to discover and characterize the nucleus, (2) to characterize the atmosphere and ionosphere, (3) to characterize the dust, and (4) to characterize the nature of the large-scale comet-solar wind interaction. While the VEGA and Giotto missions were designed to study all four areas, Suisei addressed the second and fourth. Sakigake was designed to study the solar wind conditions upstream of the comet. It is noted that NASA's Deep Space Network played an important role in spacecraft tracking.

Expedition 54 Soyuz Docking

NASA Image and Video Library

2017-12-19

Icons for the International Space Station and Soyuz MS-07 spacecraft are seen on a tracking map on a screen in the Moscow Mission Control Center as the spacecraft approaches for docking, Tuesday, Dec. 19, 2017 in Korolev, Russia. The Soyuz MS-07 spacecraft carrying Anton Shkaplerov of Roscosmos, Scott Tingle of NASA, and Norishige Kanai of the Japan Aerospace Exploration Agency (JAXA) docked with the International Space Station at 3:39 a.m. EST, Tuesday, Dec. 19 while 250 statute miles over the southern coast of Italy and joined Expedition 54 Commander Alexander Misurkin of Roscosmos, and NASA astronauts Joe Acaba and Mark Vande Hei. Photo Credit: (NASA/Joel Kowsky)

Spacecraft Orbit Anomaly Representation Using Thrust-Fourier-Coefficients with Orbit Determination Toolbox

NASA Astrophysics Data System (ADS)

Ko, H.; Scheeres, D.

2014-09-01

Representing spacecraft orbit anomalies between two separate states is a challenging but an important problem in achieving space situational awareness for an active spacecraft. Incorporation of such a capability could play an essential role in analyzing satellite behaviors as well as trajectory estimation of the space object. A general way to deal with the anomaly problem is to add an estimated perturbing acceleration such as dynamic model compensation (DMC) into an orbit determination process based on pre- and post-anomaly tracking data. It is a time-consuming numerical process to find valid coefficients to compensate for unknown dynamics for the anomaly. Even if the orbit determination filter with DMC can crudely estimate an unknown acceleration, this approach does not consider any fundamental element of the unknown dynamics for a given anomaly. In this paper, a new way of representing a spacecraft anomaly using an interpolation technique with the Thrust-Fourier-Coefficients (TFCs) is introduced and several anomaly cases are studied using this interpolation method. It provides a very efficient way of reconstructing the fundamental elements of the dynamics for a given spacecraft anomaly. Any maneuver performed by a satellite transitioning between two arbitrary orbital states can be represented as an equivalent maneuver using an interpolation technique with the TFCs. Given unconnected orbit states between two epochs due to a spacecraft anomaly, it is possible to obtain a unique control law using the TFCs that is able to generate the desired secular behavior for the given orbital changes. This interpolation technique can capture the fundamental elements of combined unmodeled anomaly events. The interpolated orbit trajectory, using the TFCs compensating for a given anomaly, can be used to improve the quality of orbit fits through the anomaly period and therefore help to obtain a good orbit determination solution after the anomaly. Orbit Determination Toolbox (ODTBX) is modified to adapt this technique in order to verify the performance of this interpolation approach. Spacecraft anomaly cases are based on either single or multiple low or high thrust maneuvers and the unknown thrust accelerations are recovered and compared with the true thrust acceleration. The advantage of this approach is to easily append TFCs and its dynamics to the pre-built ODTBX, which enables us to blend post-anomaly tracking data to improve the performance of the interpolation representation in the absence of detailed information about a maneuver. It allows us to improve space situational awareness in the areas of uncertainty propagation, anomaly characterization and track correlation.

Consensus seeking, formation keeping, and trajectory tracking in multiple vehicle cooperative control

NASA Astrophysics Data System (ADS)

Ren, Wei

Cooperative control problems for multiple vehicle systems can be categorized as either formation control problems with applications to mobile robots, unmanned air vehicles, autonomous underwater vehicles, satellites, aircraft, spacecraft, and automated highway systems, or non-formation control problems such as task assignment, cooperative transport, cooperative role assignment, air traffic control, cooperative timing, and cooperative search. The cooperative control of multiple vehicle systems poses significant theoretical and practical challenges. For cooperative control strategies to be successful, numerous issues must be addressed. We consider three important and correlated issues: consensus seeking, formation keeping, and trajectory tracking. For consensus seeking, we investigate algorithms and protocols so that a team of vehicles can reach consensus on the values of the coordination data in the presence of imperfect sensors, communication dropout, sparse communication topologies, and noisy and unreliable communication links. The main contribution of this dissertation in this area is that we show necessary and/or sufficient conditions for consensus seeking with limited, unidirectional, and unreliable information exchange under fixed and switching interaction topologies (through either communication or sensing). For formation keeping, we apply a so-called "virtual structure" approach to spacecraft formation flying and multi-vehicle formation maneuvers. As a result, single vehicle path planning and trajectory generation techniques can be employed for the virtual structure while trajectory tracking strategies can be employed for each vehicle. The main contribution of this dissertation in this area is that we propose a decentralized architecture for multiple spacecraft formation flying in deep space with formation feedback introduced. This architecture ensures the necessary precision in the presence of actuator saturation, internal and external disturbances, and stringent inter-vehicle communication limitations. A constructive approach based on the satisficing control paradigm is also applied to multi-robot coordination in hardware. For trajectory tracking, we investigate nonlinear tracking controllers for fixed wing unmanned air vehicles and nonholonomic mobile robots with velocity and heading rate constraints. The main contribution of this dissertation in this area is that our proposed tracking controllers are shown to be robust to input uncertainties and measurement noise, and are computationally simple and can be implemented with low-cost, low-power microcontrollers. In addition, our approach allows piecewise continuous reference velocity and heading rate and can be extended to derive a variety of other trajectory tracking strategies.

Control topologies for deep space formation flying spacecraft

NASA Technical Reports Server (NTRS)

Hadaegh, F. Y.; Smith, R. S.

2002-01-01

This paper gives a characterization of the equivalent topologies and uses this approach to show that there exists a control topology which achieves a global tracking objective using only local controllers.

Magellan Prelaunch Mission Operations Report

NASA Technical Reports Server (NTRS)

1989-01-01

The Magellan spacecraft will be launched from Kennedy Space Center (KSC) within a 31-day overall launch period extending from April 28 to May 28, 1989. The launch will use the Shuttle Orbiter Atlantis to lift an Inertial Upper Stage (IUS) and the Magellan Spacecraft into low Earth orbit. After the Shuttle achieves its parking orbit, the IUS and attached Magellan spacecraft are deployed from the payload bay. After a short coast time, the two-stage IUS is fired to inject the Magellan spacecraft into an Earth-Venus transfer trajectory. The Magellan spacecraft is powered by single degree of freedom, sun-tracking, solar panels charging a set of nickel-cadmium batteries. The spacecraft is three-axis stabilized by reaction wheels using gyros and a star sensor for attitude reference. The spacecraft carries a solid rocket motor for Venus Orbit Insertion (VOI). A hydrazine propulsion system allows trajectory correction and prevents saturation of the reaction wheels. Communication with Earth through the Deep Space Network (DSN) is provided by S- and X-band telemetry channels, through alternatively a low, medium, or 3.7 m high-gain parabolic antenna rigidly attached to the spacecraft. The high-gain antenna also serves as the radar and radiometer antenna during orbit around Venus.

COBE navigation with one-way return-link Doppler in the post-helium-venting phase

NASA Technical Reports Server (NTRS)

Dunham, Joan; Nemesure, M.; Samii, M. V.; Maher, M.; Teles, Jerome; Jackson, J.

1991-01-01

The results of a navigation experiment with one way return link Doppler tracking measurements for operational orbit determination of the Cosmic Background Explorer (COBE) spacecraft are presented. The frequency of the tracking signal for the one way measurements was stabilized with an Ultrastable Oscillator (USO), and the signal was relayed by the Tracking and Data Relay Satellite System (TDRSS). The study achieved three objectives: space qualification of TDRSS noncoherent one way return link Doppler tracking; determination of flight performance of the USO coupled to the second generation TDRSS compatible user transponder; and verification of algorithms for navigation using actual one way tracking data. Orbit determination and the inflight USO performance evaluation results are presented.

Neutron Measurements for Radiation Protection in Low Earth Orbit - History and Future

NASA Technical Reports Server (NTRS)

Golightly, M. J.; Se,pmes. E/

2003-01-01

The neutron environment inside spacecraft has been of interest from a scientific and radiation protection perspective since early in the history of manned spaceflight. With 1:.1e exception of a few missions which carried plutonium-fueled radioisotope thermoelectric generators, all of the neutrons inside the spacecraft are secondary radiations resulting from interactions of high-energy charged particles with nuclei in the Earth's atmosphere, spacecraft structural materials, and the astronaut's own bodies. Although of great interest, definitive measurements of the spacecraft neutron field have been difficult due to the wide particle energy range and the limited available volume and power for traditional techniques involving Bonner spheres. A multitude of measurements, however, have been made of the neutron environment inside spacecraft. The majority of measurements were made using passive techniques including metal activation fo ils, fission foils, nuclear photoemulsions, plastic track detectors, and thermoluminescent detectors. Active measurements have utilized proton recoil spectrometers (stilbene), Bonner Spheres eRe proportional counter based), and LiI(Eu)phoswich scintillation detectors. For the International Space Station (ISS), only the plastic track! thermoluminescent detectors are used with any regularity. A monitoring program utilizing a set of active Bonner spheres was carried out in the ISS Lab module from March - December 200l. These measurements provide a very limited look at the crew neutron exposure, both in time coverage and neutron energy coverage. A review of the currently published data from past flights will be made and compared with the more recent results from the ISS. Future measurement efforts using currently available techniques and those in development will be also discussed.

A history of the deep space network

NASA Technical Reports Server (NTRS)

Corliss, W. R.

1976-01-01

The Deep Space Network (DSN) has been managed and operated by the Jet Propulsion Laboratory (JPL) under NASA contract ever since NASA was formed in late 1958. The Tracking and data acquisition tasks of the DSN are markedly different from those of the other NASA network, STDN. STDN, which is an amalgamation of the satellite tracking network (STADAN) and the Manned Space Flight Network (MSFN), is primarily concerned with supporting manned and unmanned earth satellites. In contrast, the DSN deals with spacecraft that are thousands to hundreds of millions of miles away. The radio signals from these distant craft are many orders of magnitude weaker than those from nearby satellites. Distance also makes precise radio location more difficult; and accurate trajectory data are vital to deep space navigation in the vicinities of the other planets of the solar system. In addition to tracking spacecraft and acquiring data from them, the DSN is required to transmit many thousands of commands to control the sophisticated planetary probes and interplanetary monitoring stations. To meet these demanding requirements, the DSN has been compelled to be in the forefront of technology.

State Tracking and Fault Diagnosis for Dynamic Systems Using Labeled Uncertainty Graph.

PubMed

Zhou, Gan; Feng, Wenquan; Zhao, Qi; Zhao, Hongbo

2015-11-05

Cyber-physical systems such as autonomous spacecraft, power plants and automotive systems become more vulnerable to unanticipated failures as their complexity increases. Accurate tracking of system dynamics and fault diagnosis are essential. This paper presents an efficient state estimation method for dynamic systems modeled as concurrent probabilistic automata. First, the Labeled Uncertainty Graph (LUG) method in the planning domain is introduced to describe the state tracking and fault diagnosis processes. Because the system model is probabilistic, the Monte Carlo technique is employed to sample the probability distribution of belief states. In addition, to address the sample impoverishment problem, an innovative look-ahead technique is proposed to recursively generate most likely belief states without exhaustively checking all possible successor modes. The overall algorithms incorporate two major steps: a roll-forward process that estimates system state and identifies faults, and a roll-backward process that analyzes possible system trajectories once the faults have been detected. We demonstrate the effectiveness of this approach by applying it to a real world domain: the power supply control unit of a spacecraft.

Tracking and data relay satellite system: NASA's new spacecraft data acquisition system

NASA Astrophysics Data System (ADS)

Schneider, W. C.; Garman, A. A.

The growth in NASA's ground network complexity and cost triggered a search for an alternative. Through a lease service contract, Western Union will provide to NASA 10 years of space communications services with a Tracking and Data Relay Satellite System (TDRSS). A constellation of four operating satellites in geostationary orbit and a single ground terminal will provide complete tracking, telemetry and command service for all of NASA's Earth orbital satellites below an altitude of 12,000 km. The system is shared: two satellites will be dedicated to NASA service; a third will provide backup as a shared spare; the fourth satellite will be dedicated to Western Union's Advanced Westar commercial service. Western Union will operate the ground terminal and provide operational satellite control. NASA's Network Control Center will provide the focal point for scheduling user services and controlling the interface between TDRSS and the rest of the NASA communications network, project control centers and data processing facilities. TDRSS single access user spacecraft data systems should be designed for efficient time shared data relay support. Reimbursement policy and rate structure for non-NASA users are currently being developed.

Nimbus-F to carry advanced weather instruments

NASA Technical Reports Server (NTRS)

1975-01-01

Meteorological research instruments launched aboard NASA's Nimbus-F spacecraft are briefly described along with the Nimbus satellite program initiated to develop an observatory system capable of meeting the research and development needs of the nation's atmospheric and earth sciences program. The following aspects of the mission are described: spacecraft design, launch operations, sequence of orbital events, and operations control and tracking. The Global Atmospheric Research program is discussed in terms of the Nimbus-F experiments and atmospheric sounding instruments.

National Space Science Data Center (NSSDC) Data Listing

NASA Technical Reports Server (NTRS)

1980-01-01

Satellite and nonsatellite data available from the National Space Science Data Center are listed. The Satellite Data listing includes the spacecraft name, launch date, and an alphabetical list of experiments. The Non-Satellite Data listing contains ground based data, models, computer routines, and composite spacecraft data. The data set name, data form code, quantity of data, and the time space covered are included in the data sets of both listings where appropriate. Geodetic tracking data sets are also included.

MOORE: A prototype expert system for diagnosing spacecraft problems

NASA Technical Reports Server (NTRS)

Howlin, Katherine; Weissert, Jerry; Krantz, Kerry

1988-01-01

MOORE is a rule-based, prototype expert system that assists in diagnosing operational Tracking and Data Relay Satellite (TDRS) problems. It is intended to assist spacecraft engineers at the TDRS ground terminal in trouble shooting problems that are not readily solved with routine procedures, and without expert counsel. An additional goal of the prototype system is to develop in-house expert system and knowledge engineering skills. The prototype system diagnoses antenna pointing and earth pointing problems that may occur within the TDRS Attitude Control System (ACS). Plans include expansion to fault isolation of problems in the most critical subsystems of the TDRS spacecraft. Long term benefits are anticipated with use of an expert system during future TDRS programs with increased mission support time, reduced problem solving time, and retained expert knowledge and experience. Phase 2 of the project is intended to provide NASA the necessary expertise and capability to define requirements, evaluate proposals, and monitor the development progress of a highly competent expert system for NASA's Tracking Data Relay Satellite. Phase 2 also envisions addressing two unexplored applications for expert systems, spacecraft integration and tests (I and T) and support to launch activities. The concept, goals, domain, tools, knowledge acquisition, developmental approach, and design of the expert system. It will explain how NASA obtained the knowledge and capability to develop the system in-house without assistance from outside consultants. Future plans will also be presented.

Particle Tracks in Aerogel

NASA Image and Video Library

2005-11-03

In an experiment using a special air gun, particles are shot into aerogel at high velocities. Closeup of particles leaving a carrot-shaped trail in the aerogel are shown here. Aerogel was used on NASA Stardust spacecraft.

Simulation gravity modeling to spacecraft-tracking data - Analysis and application

NASA Technical Reports Server (NTRS)

Phillips, R. J.; Sjogren, W. L.; Abbott, E. A.; Zisk, S. H.

1978-01-01

It is proposed that line-of-sight gravity measurements derived from spacecraft-tracking data can be used for quantitative subsurface density modeling by suitable orbit simulation procedures. Such an approach avoids complex dynamic reductions and is analogous to the modeling of conventional surface gravity data. This procedure utilizes the vector calculations of a given gravity model in a simplified trajectory integration program that simulates the line-of-sight gravity. Solutions from an orbit simulation inversion and a dynamic inversion on Doppler observables compare well (within 1% in mass and size), and the error sources in the simulation approximation are shown to be quite small. An application of this technique is made to lunar crater gravity anomalies by simulating the complete Bouguer correction to several large young lunar craters. It is shown that the craters all have negative Bouguer anomalies.

Tracking and data relay satellite system configuration and tradeoff study, part 1. Volume 1: Summary volume

NASA Technical Reports Server (NTRS)

1972-01-01

Study efforts directed at defining all TDRS system elements are summarized. Emphasis was placed on synthesis of a space segment design optimized to support low and medium data rate user spacecraft and launched with Delta 2914. A preliminary design of the satellite was developed and conceptual designs of the user spacecraft terminal and TDRS ground station were defined. As a result of the analyses and design effort it was determined that (1) a 3-axis-stabilized tracking and data relay satellite launched on a Delta 2914 provides telecommunications services considerably in excess of that required by the study statement; and (2) the design concept supports the needs of the space shuttle and has sufficient growth potential and flexibility to provide telecommunications services to high data rate users. Recommendations for further study are included.

The control net of Mars - May 1977. [from Viking lander spacecraft radio tracking data

NASA Technical Reports Server (NTRS)

Davies, M. E.

1978-01-01

The development of planet-wide control nets of Mars is reviewed, and the May 1977 update is described. This updated control net was computed by means of a large single-block analytical triangulation incorporating the new direction of the spin axis and the new rotation rate of Mars, as determined from radio tracking data provided by the Viking lander spacecraft. The analytical triangulation adjusts for planimetric control only (areocentric latitude and longitude) and for the camera orientation angles. Most of the areocentric radii at the control points were interpolated from radio occultation measurements, but a few were determined photogrammetically, and a substantial number were derived from elevation contours on the 1976 USGS topographic series of Mars maps. A value of V, measured from Mars' vernal equinox along the equator to the prime meridian (Airy-0) is presented.

Tracking and data relay satellite system (TDRSS) - A worldwide view from space

NASA Technical Reports Server (NTRS)

Macoughtry, W. O.; Harris, D. W.

1983-01-01

The development, performance levels, and operational use of the TDRSS satellite system are outlined. The TDRSS spacecraft were conceived in the mid-1960s by NASA as a means of using GEO-positioned satellites to eliminate existing ground stations. The main ground terminal becomes Goddard Space Flight Center, through which users other than the Shuttle can also gain access. The TDRSS functions as a relay vehicle, with very little on-board processing except for status reports inserted into the data stream. Use of the TDRSS system by nonNASA agencies currently costs $110/min for forwards, return, and tracking, $24/min for forward service alone, and $8/min for return service only. The spacecraft can store data on board and dump it to the ground station during the limited hours of operation.

Some methods of computing platform transmitter terminal location estimates. [ARGOS system; whale tracking

NASA Technical Reports Server (NTRS)

Hoisington, C. M.

1984-01-01

A position estimation algorithm was developed to track a humpback whale tagged with an ARGOS platform after a transmitter deployment failure and the whale's diving behavior precluded standard methods. The algorithm is especially useful where a transmitter location program exists; it determines the classical keplarian elements from the ARGOS spacecraft position vectors included with the probationary file messages. A minimum of three distinct messages are required. Once the spacecraft orbit is determined, the whale is located using standard least squares regression techniques. Experience suggests that in instances where circumstances inherent in the experiment yield message data unsuitable for the standard ARGOS reduction, (message data may be too sparse, span an insufficient period, or include variable-length messages). System ARGOS can still provide much valuable location information if the user is willing to accept the increased location uncertainties.

Feature extraction algorithm for space targets based on fractal theory

NASA Astrophysics Data System (ADS)

Tian, Balin; Yuan, Jianping; Yue, Xiaokui; Ning, Xin

2007-11-01

In order to offer a potential for extending the life of satellites and reducing the launch and operating costs, satellite servicing including conducting repairs, upgrading and refueling spacecraft on-orbit become much more frequently. Future space operations can be more economically and reliably executed using machine vision systems, which can meet real time and tracking reliability requirements for image tracking of space surveillance system. Machine vision was applied to the research of relative pose for spacecrafts, the feature extraction algorithm was the basis of relative pose. In this paper fractal geometry based edge extraction algorithm which can be used in determining and tracking the relative pose of an observed satellite during proximity operations in machine vision system was presented. The method gets the gray-level image distributed by fractal dimension used the Differential Box-Counting (DBC) approach of the fractal theory to restrain the noise. After this, we detect the consecutive edge using Mathematical Morphology. The validity of the proposed method is examined by processing and analyzing images of space targets. The edge extraction method not only extracts the outline of the target, but also keeps the inner details. Meanwhile, edge extraction is only processed in moving area to reduce computation greatly. Simulation results compared edge detection using the method which presented by us with other detection methods. The results indicate that the presented algorithm is a valid method to solve the problems of relative pose for spacecrafts.

Spinning Rocket Simulator Turntable Design

NASA Technical Reports Server (NTRS)

Miles, Robert W.

2001-01-01

Contained herein is the research and data acquired from the Turntable Design portion of the Spinning Rocket Simulator (SRS) project. The SRS Project studies and eliminates the effect of coning on thrust-propelled spacecraft. This design and construction of the turntable adds a structural support for the SRS model and two degrees of freedom. The two degrees of freedom, radial and circumferential, will help develop a simulated thrust force perpendicular to the plane of the spacecraft model while undergoing an unstable coning motion. The Turntable consists of a ten-foot linear track mounted to a sprocket and press-fit to a thrust bearing. A two-inch high column grounded by a Triangular Baseplate supports this bearing and houses the slip rings and pressurized, air-line swivel. The thrust bearing allows the entire system to rotate under the moment applied through the chain-driven sprocket producing a circumferential degree of freedom. The radial degree of freedom is given to the model through the helically threaded linear track. This track allows the Model Support and Counter Balance to simultaneously reposition according to the coning motion of the Model. Two design factors that hinder the linear track are bending and twist due to torsion. A Standard Aluminum "C" channel significantly reduces these two deflections. Safety considerations dictate the design of all the components involved in this project.

Smoothing and Predicting Celestial Pole Offsets using a Kalman Filter and Smoother

NASA Astrophysics Data System (ADS)

Nastula, J.; Chin, T. M.; Gross, R. S.; Winska, M.; Winska, J.

2017-12-01

Since the early days of interplanetary spaceflight, accounting for changes in the Earth's rotation is recognized to be critical for accurate navigation. In the 1960s, tracking anomalies during the Ranger VII and VIII lunar missions were traced to errors in the Earth orientation parameters. As a result, Earth orientation calibration methods were improved to support the Mariner IV and V planetary missions. Today, accurate Earth orientation parameters are used to track and navigate every interplanetary spaceflight mission. The interplanetary spacecraft tracking and navigation teams at JPL require the UT1 and polar motion parameters, and these Earth orientation parameters are estimated by the use of a Kalman filter to combine past measurements of these parameters and predict their future evolution. A model was then used to provide the nutation/precession components of the Earth's orientation separately. As a result, variations caused by the free core nutation were not taken into account. But for the highest accuracy, these variations must be considered. So JPL recently developed an approach based upon the use of a Kalman filter and smoother to provide smoothed and predicted celestial pole offsets (CPOs) to the interplanetary spacecraft tracking and navigation teams. The approach used at JPL to do this and an evaluation of the accuracy of the predicted CPOs will be given here.

Direct Data Distribution From Low-Earth Orbit

NASA Technical Reports Server (NTRS)

Budinger, James M.; Fujikawa, Gene; Kunath, Richard R.; Nguyen, Nam T.; Romanofsky, Robert R.; Spence, Rodney L.

1997-01-01

NASA Lewis Research Center (LeRC) is developing the space and ground segment technologies necessary to demonstrate a direct data distribution (1)3) system for use in space-to-ground communication links from spacecraft in low-Earth orbit (LEO) to strategically located tracking ground terminals. The key space segment technologies include a K-band (19 GHz) MMIC-based transmit phased array antenna, and a multichannel bandwidth- and power-efficient digital encoder/modulate with an aggregate data rate of 622 Mb/s. Along with small (1.8 meter), low-cost tracking terminals on the ground, the D3 system enables affordable distribution of data to the end user or archive facility through interoperability with commercial terrestrial telecommunications networks. The D3 system is applicable to both government and commercial science and communications spacecraft in LEO. The features and benefits of the D3 system concept are described. Starting with typical orbital characteristics, a set of baseline requirements for representative applications is developed, including requirements for onboard storage and tracking terminals, and sample link budgets are presented. Characteristics of the transmit array antenna and digital encoder/modulator are described. The architecture and components of the tracking terminal are described, including technologies for the next generation terminal. Candidate flights of opportunity for risk mitigation and space demonstration of the D3 features are identified.

SPECS: Orbital debris removal

NASA Technical Reports Server (NTRS)

1991-01-01

The debris problem has reached a stage at which the risk to satellites and spacecraft has become substantial in low Earth orbit (LEO). This research discovered that small particles posed little threat to spacecraft because shielding can effectively prevent these particles from damaging the spacecraft. The research also showed that, even though collision with a large piece of debris could destroy the spacecraft, the large pieces of debris pose little danger because they can be tracked and the spacecraft can be maneuvered away from these pieces. Additionally, there are many current designs to capture and remove large debris particles from the space environment. From this analysis, it was decided to concentrate on the removal of medium-sized orbital debris, that is, those pieces ranging from 1 cm to 50 cm in size. The current design incorporates a transfer vehicle and a netting vehicle to capture the medium-sized debris. The system is based near an operational space station located at 28.5 deg inclination and 400 km altitude. The system uses ground-based tracking to determine the location of a satellite breakup or debris cloud. These data are uploaded to the transfer vehicle, which proceeds to rendezvous with the debris at a lower altitude parking orbit. Next, the netting vehicle is deployed, tracks the targeted debris, and captures it. After expending the available nets, the netting vehicle returns to the transfer vehicle for a new netting module and continues to capture more debris in the target area. Once all the netting modules are expended, the transfer vehicle returns to the space station's orbit where it is resupplied with new netting modules from a space shuttle load. The new modules are launched by the shuttle from the ground and the expended modules are taken back to Earth for removal of the captured debris, refueling, and repacking of the nets. Once the netting modules are refurbished, they are taken back into orbit for reuse. In a typical mission, the system has the ability to capture 50 pieces of orbital debris. One mission will take approximately six months and the system is designed to allow for a 30 deg inclination change on the outgoing and incoming trips of the transfer vehicle.

Dust Devil Tracks

NASA Image and Video Library

2012-11-13

This image from NASA 2001 Mars Odyssey spacecraft of Daedalia Planum shows the termination or end of a single flow. In this case it is the end of the brighter/rougher flow on the right side of the image.

Tracking Snowballs

NASA Image and Video Library

2010-11-18

Icy particles in the cloud around Hartley 2, as seen by NASA EPOXI mission spacecraft. A star moving through the background is marked with red and moves in a particular direction, with a particular speed; icy particles move in random directions.

Wiring test program insulation material related properties

NASA Technical Reports Server (NTRS)

Reher, Heinz-Josef

1995-01-01

This viewgraph presentation provides an overview of activities at DASA-RI concerning the testing of wires for manned spacecraft, including test facilities, arc-tracking tests, flammability tests, microgravity tests, and standardization, and outlines future activities.

Deep Space Telecommunications Systems Engineering

NASA Technical Reports Server (NTRS)

Yuen, J. H. (Editor)

1982-01-01

Descriptive and analytical information useful for the optimal design, specification, and performance evaluation of deep space telecommunications systems is presented. Telemetry, tracking, and command systems, receiver design, spacecraft antennas, frequency selection, interference, and modulation techniques are addressed.

Goldstone 70-Meter

NASA Image and Video Library

2013-12-18

Late night in the desert: Goldstone 230-foot 70-meter antenna tracks spacecraft day and night. This photograph was taken on Jan. 11, 2012. The Goldstone Deep Space Communications Complex is located in the Mojave Desert in California, USA.

A network architecture for precision formation flying using the IEEE 802.11 MAC Protocol

NASA Technical Reports Server (NTRS)

Clare, Loren P.; Gao, Jay L.; Jennings, Esther H.; Okino, Clayton

2005-01-01

Precision Formation Flying missions involve the tracking and maintenance of spacecraft in a desired geometric formation. The strong coupling of spacecraft in formation flying control requires inter-spacecraft communication to exchange information. In this paper, we present a network architecture that supports PFF control, from the initial random deployment phase to the final formation. We show that a suitable MAC layer for the application protocol is IEEE's 802.11 MAC protocol. IEEE 802.11 MAC has two modes of operations: DCF and PCF. We show that DCF is suitable for the initial deployment phase while switching to PCF when the spacecraft are in formation improves jitter and throughput. We also consider the effect of routing on protocol performance and suggest when it is profitable to turn off route discovery to achieve better network performance.

Spacecraft-produced neutron fluxes on Skylab

NASA Technical Reports Server (NTRS)

Quist, T. C.; Furst, M.; Burnett, D. S.; Baum, J. H.; Peacock, C. L., Jr.; Perry, D. G.

1977-01-01

Estimates of neutron fluxes in different energy ranges are reported for the Skylab spacecraft. Detectors composed of uranium, thorium, and bismuth foils with mica as a fission track recorder, as well as boron foils with cellulose acetate as an alpha-particle recorder, were deployed at different positions in the Orbital Workshop. It was found that the Skylab neutron flux was dominated by high energy (greater than 1 MeV) contributions and that there was no significant time variation in the fluxes. Firm upper limits of 7-15 neutrons/sq cm-sec, depending on the detector location in the spacecraft, were established for fluxes above 1 MeV. Below 1 MeV, the neutron fluxes were about an order of magnitude lower. The neutrons are interpreted as originating from the interactions of leakage protons from the radiation belt with the spacecraft.

Attitude control/momentum management and payload pointing in advanced space vehicles

NASA Technical Reports Server (NTRS)

Parlos, Alexander G.; Jayasuriya, Suhada

1990-01-01

The design and evaluation of an attitude control/momentum management system for highly asymmetric spacecraft configurations are presented. The preliminary development and application of a nonlinear control system design methodology for tracking control of uncertain systems, such as spacecraft payload pointing systems are also presented. Control issues relevant to both linear and nonlinear rigid-body spacecraft dynamics are addressed, whereas any structural flexibilities are not taken into consideration. Results from the first task indicate that certain commonly used simplifications in the equations of motions result in unstable attitude control systems, when used for highly asymmetric spacecraft configurations. An approach is suggested circumventing this problem. Additionally, even though preliminary results from the second task are encouraging, the proposed nonlinear control system design method requires further investigation prior to its application and use as an effective payload pointing system design technique.

High-Capacity Communications from Martian Distances Part 4: Assessment of Spacecraft Pointing Accuracy Capabilities Required For Large Ka-Band Reflector Antennas

NASA Technical Reports Server (NTRS)

Hodges, Richard E.; Sands, O. Scott; Huang, John; Bassily, Samir

2006-01-01

Improved surface accuracy for deployable reflectors has brought with it the possibility of Ka-band reflector antennas with extents on the order of 1000 wavelengths. Such antennas are being considered for high-rate data delivery from planetary distances. To maintain losses at reasonable levels requires a sufficiently capable Attitude Determination and Control System (ADCS) onboard the spacecraft. This paper provides an assessment of currently available ADCS strategies and performance levels. In addition to other issues, specific factors considered include: (1) use of "beaconless" or open loop tracking versus use of a beacon on the Earth side of the link, and (2) selection of fine pointing strategy (body-fixed/spacecraft pointing, reflector pointing or various forms of electronic beam steering). Capabilities of recent spacecraft are discussed.

KSC-06pd2263

NASA Image and Video Library

2006-10-10

KENNEDY SPACE CENTER, FLA. - With a convoy of escorts, the STEREO spacecraft is transported to Launch Pad 17-B on Cape Canaveral Air Force Station. At the pad the spacecraft will be lifted into the mobile service tower. STEREO stands for Solar Terrestrial Relations Observatory and comprises two spacecraft. The STEREO mission is the first to take measurements of the sun and solar wind in 3-dimension. This new view will improve our understanding of space weather and its impact on the Earth. The STEREO mission is managed by Goddard Space Flight Center. The Applied Physics Laboratory designed and built the spacecraft. The laboratory will maintain command and control of the observatories throughout the mission, while NASA tracks and receives the data, determines the orbit of the satellites, and coordinates the science results. STEREO is expected to lift off Oct. 25. Photo credit: NASA/George Shelton

Summary of measurements of high-LET particle radiation in U.S. manned space missions.

PubMed

Benton, E V; Peterson, D D; Henke, R P

1977-01-01

A summary of measurements of high-LET particle radiation inside U.S. manned spacecraft is given for ASTP (Apollo Soyuz Test Project), Skylab and Apollo missions. The results include particle fluxes, integral LET spectra, and stopping-density charge distributions derived from measurements made in plastic nuclear track detectors worn by astronauts and located at various positions inside spacecraft. The results presented for different missions cover a wide range of shielding depth and missions type.

Spacecraft Line-of-Sight Stabilization Using LWIR Earth Signature

NASA Technical Reports Server (NTRS)

Quadrelli, Marco B.; Piazzolla, Sabino

2012-01-01

The objective of this study is to investigate the potential of using the bright and near-uniform Earth infrared (or wavelength infrared, LWIR) signature as a stable reference for accurate (micro-rad or less) inertial pointing and tracking on-board an space vehicle, including the determination of the fundamental limits of applicability of the proposed method for space missions. We demonstrate sub-micro radian level pointing accuracy under a representative set of disturbances experienced by the spacecraft in orbit.

Expedition 23 Soyuz Rollout

NASA Image and Video Library

2010-03-30

Russian security officers and their dog patrol the railroad track ahead of the Soyuz TMA-18 spacecraft as it is rolled out by train to the launch pad at the Baikonur Cosmodrome, Kazakhstan, Wednesday, March, 31, 2010. The launch of the Soyuz spacecraft with Expedition 23 Soyuz Commander Alexander Skvortsov of Russia, Flight Engineer Mikhail Kornienko of Russia, and NASA Flight Engineer Tracy Caldwell Dyson is scheduled for Friday, April 2, 2010 at 10:04 a.m. Kazakhstan time. Photo Credit (NASA/Bill Ingalls)

NASA Spacecraft Tracks Argentine Flooding

NASA Image and Video Library

2015-08-19

Northwest of Buenos Aires, Argentina, seven straight days of torrential rains of up to 16 inches 40 centimeters in August 2015 resulted in flooding between the cities of Escobar and Campana as seen by NASA Terra spacecraft. The flooding has since eased, allowing some evacuated residents of the 39 affected municipalities to return to their homes. The flooding was captured in this satellite image acquired Aug. 16, 2015, by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument on NASA's Terra spacecraft. The image covers an area of 16.7 by 17.4 miles (26.9 by 28 kilometers), and is located at 34.2 degrees south, 58.6 degrees west. http://photojournal.jpl.nasa.gov/catalog/PIA19871

An orbit simulation study of a geopotential research mission including satellite-to-satellite tracking and disturbance compensation systems

NASA Technical Reports Server (NTRS)

Antreasian, Peter G.

1988-01-01

Two orbit simulations, one representing the actual Geopotential Research Mission (GRM) orbit and the other representing the orbit estimated from orbit determination techniques, are presented. A computer algorithm was created to simulate GRM's drag compensation mechanism so the fuel expenditure and proof mass trajectories relative to the spacecraft centroid could be calculated for the mission. The results of the GRM DISCOS simulation demonstrated that the spacecraft can essentially be drag-free. The results showed that the centroid of the spacecraft can be controlled so that it will not deviate more than 1.0 mm in any direction from the centroid of the proof mass.

Attitude control challenges for earth orbiters of the 1980's

NASA Technical Reports Server (NTRS)

Hibbard, W.

1980-01-01

Experience gained in designing attitude control systems for orbiting spacecraft of the late 1980's is related. Implications for satellite attitude control design of the guidance capabilities, rendezvous and recovery requirements, use of multiple-use spacecraft and the development of large spacecraft associated with the advent of the Space Shuttle are considered. Attention is then given to satellite attitude control requirements posed by the Tracking and Data Relay Satellite System, the Global Positioning System, the NASA End-to-End Data System, and Shuttle-associated subsatellites. The anticipated completion and launch of the Space Telescope, which will provide one of the first experiences with the new generation of attitude control, is also pointed out.

Robust fault-tolerant tracking control design for spacecraft under control input saturation.

PubMed

Bustan, Danyal; Pariz, Naser; Sani, Seyyed Kamal Hosseini

2014-07-01

In this paper, a continuous globally stable tracking control algorithm is proposed for a spacecraft in the presence of unknown actuator failure, control input saturation, uncertainty in inertial matrix and external disturbances. The design method is based on variable structure control and has the following properties: (1) fast and accurate response in the presence of bounded disturbances; (2) robust to the partial loss of actuator effectiveness; (3) explicit consideration of control input saturation; and (4) robust to uncertainty in inertial matrix. In contrast to traditional fault-tolerant control methods, the proposed controller does not require knowledge of the actuator faults and is implemented without explicit fault detection and isolation processes. In the proposed controller a single parameter is adjusted dynamically in such a way that it is possible to prove that both attitude and angular velocity errors will tend to zero asymptotically. The stability proof is based on a Lyapunov analysis and the properties of the singularity free quaternion representation of spacecraft dynamics. Results of numerical simulations state that the proposed controller is successful in achieving high attitude performance in the presence of external disturbances, actuator failures, and control input saturation. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

Orbital debris removal and meteoroid deflection

NASA Astrophysics Data System (ADS)

Campbell, Jonathan W.; Taylor, Charles R.; Smalley, Larry L.; Dickerson, Thomas

1998-11-01

Orbital debris in low-Earth orbit in the size range from 1 to 10 cm in diameter can be detected but not tracked reliably enough to be avoided by spacecraft. It can cause catastrophic damage even to a shielded spacecraft. With adaptive optics, a ground-based pulsed laser ablating the debris surface can produce enough propulsion in several hundred pulses to cause such debris to reenter the atmosphere. A single laser station could remove all of the 1 - 10 cm debris in three years or less. A technology demonstration of laser space propulsion is proposed which would pave the way for the implementation of such a debris removal system. The cost of the proposed demonstration is comparable with the estimated annual cost of spacecraft operations in the present orbital debris environment. Orbital debris is not the only space junk that is deleterious to the Earth's environment. Collisions with asteroids have caused major havoc to the Earth's biosphere many times in the ancient past. Since the possibility still exists for major impacts of asteroids with the Earth, it shown that it is possible to scale up the systems to prevent these catastrophic collisions providing sufficient early warning is available from new generation space telescopes plus deep space radar tracking.

Formation flying for electric sails in displaced orbits. Part II: Distributed coordinated control

NASA Astrophysics Data System (ADS)

Wang, Wei; Mengali, Giovanni; Quarta, Alessandro A.; Yuan, Jianping

2017-09-01

We analyze a cooperative control framework for electric sail formation flying around a heliocentric displaced orbit, aiming at observing the polar region of a celestial body. The chief spacecraft is assumed to move along an elliptic displaced orbit, while each deputy spacecraft adjusts its thrust vector (that is, both its sail attitude and characteristic acceleration) in order to track a prescribed relative trajectory. The relative motion of the electric sail formation system is formulated in the chief rotating frame, where the control inputs of each deputy are the relative sail attitude angles and the relative lightness number with respect to those of the chief. The information exchange among the spacecraft, characterized by the communication topology, is represented by a weighted graph. Two typical cases, according to whether the communication graph is directed or undirected, are discussed. For each case, a distributed coordinated control law is designed in such a way that each deputy not only tracks the chief state, but also makes full use of information from its neighbors, thus increasing the redundancy and robustness of the formation system in case of failure among the communication links. Illustrative examples show the effectiveness of the proposed approach.

Space Shuttle Projects

NASA Image and Video Library

1988-01-01

This artist's concept drawing depicts the Tracking and Data Relay Satellite-C (TDRS-C), which was the primary payload of the Space Shuttle Discovery on the STS-26 mission, launched on September 29, 1988. The TDRS system provides almost uninterrupted communications with Earth-orbiting Shuttles and satellites, and had replaced the intermittent coverage provided by globe-encircling ground tracking stations used during the early space program. The TDRS can transmit and receive data, and track a user spacecraft in a low Earth orbit. The deployment of TDRS-G on the STS-70 mission being the latest in the series, NASA has successfully launched six TDRSs.

KSC-2009-5208

NASA Image and Video Library

2009-09-23

CAPE CANAVERAL, Fla. – Approaching rain clouds at dawn hover over Central Florida's east coast, effectively causing the scrub of the Space Tracking and Surveillance System - Demonstrator spacecraft from Launch Pad 17-B at Cape Canaveral Air Force Station. STSS Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detection, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 24. Photo credit: NASA/Jack Pfaller

Maneuver Planning for Conjunction Risk Mitigation with Ground-track Control Requirements

NASA Technical Reports Server (NTRS)

McKinley, David

2008-01-01

The planning of conjunction Risk Mitigation Maneuvers (RMM) in the presence of ground-track control requirements is analyzed. Past RMM planning efforts on the Aqua, Aura, and Terra spacecraft have demonstrated that only small maneuvers are available when ground-track control requirements are maintained. Assuming small maneuvers, analytical expressions for the effect of a given maneuver on conjunction geometry are derived. The analytical expressions are used to generate a large trade space for initial RMM design. This trade space represents a significant improvement in initial maneuver planning over existing methods that employ high fidelity maneuver models and propagation.

KSC-2013-1226

NASA Image and Video Library

2013-01-29

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41, the United Launch Alliance Atlas V rocket set to carry NASA's Tracking and Data Relay Satellite, TDRS-K, nears the launch pad after leaving the Vertical Integration Facility. Liftoff for the TDRS-K is planned for Jan. 30, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1234

NASA Image and Video Library

2013-01-29

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41, the United Launch Alliance Atlas V rocket set to carry NASA's Tracking and Data Relay Satellite, TDRS-K, arrives at the launch pad after leaving the Vertical Integration Facility. Liftoff for the TDRS-K is planned for Jan. 30, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1238

NASA Image and Video Library

2013-01-29

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41, the United Launch Alliance Atlas V rocket set to carry NASA's Tracking and Data Relay Satellite, TDRS-K, stands at the launch pad after leaving the Vertical Integration Facility. Liftoff for the TDRS-K is planned for Jan. 30, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1230

NASA Image and Video Library

2013-01-29

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41, the United Launch Alliance Atlas V rocket set to carry NASA's Tracking and Data Relay Satellite, TDRS-K, arrives at the launch pad after leaving the Vertical Integration Facility. Liftoff for the TDRS-K is planned for Jan. 30, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1217

NASA Image and Video Library

2013-01-29

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41, the United Launch Alliance Atlas V rocket set to carry NASA's Tracking and Data Relay Satellite, TDRS-K, moves from the Vertical Integration Facility to the launch pad. Liftoff for the TDRS-K is planned for Jan. 30, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1219

NASA Image and Video Library

2013-01-29

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41, the United Launch Alliance Atlas V rocket set to carry NASA's Tracking and Data Relay Satellite, TDRS-K, moves toward the launch pad after leaving the Vertical Integration Facility. . Liftoff for the TDRS-K is planned for Jan. 30, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1228

NASA Image and Video Library

2013-01-29

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41, the United Launch Alliance Atlas V rocket set to carry NASA's Tracking and Data Relay Satellite, TDRS-K, nears the launch pad after leaving the Vertical Integration Facility. Liftoff for the TDRS-K is planned for Jan. 30, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1221

NASA Image and Video Library

2013-01-29

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41, the United Launch Alliance Atlas V rocket set to carry NASA's Tracking and Data Relay Satellite, TDRS-K, moves toward the launch pad after leaving the Vertical Integration Facility. Liftoff for the TDRS-K is planned for Jan. 30, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1239

NASA Image and Video Library

2013-01-29

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41, the United Launch Alliance Atlas V rocket set to carry NASA's Tracking and Data Relay Satellite, TDRS-K, stands at the launch pad after leaving the Vertical Integration Facility. Liftoff for the TDRS-K is planned for Jan. 30, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1232

NASA Image and Video Library

2013-01-29

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41, the United Launch Alliance Atlas V rocket set to carry NASA's Tracking and Data Relay Satellite, TDRS-K, arrives at the launch pad after leaving the Vertical Integration Facility. Liftoff for the TDRS-K is planned for Jan. 30, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1236

NASA Image and Video Library

2013-01-29

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41, the United Launch Alliance Atlas V rocket set to carry NASA's Tracking and Data Relay Satellite, TDRS-K, stands at the launch pad after leaving the Vertical Integration Facility. Liftoff for the TDRS-K is planned for Jan. 30, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1223

NASA Image and Video Library

2013-01-29

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41, the United Launch Alliance Atlas V rocket set to carry NASA's Tracking and Data Relay Satellite, TDRS-K, nears the launch pad after leaving the Vertical Integration Facility. Liftoff for the TDRS-K is planned for Jan. 30, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1235

NASA Image and Video Library

2013-01-29

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41, the United Launch Alliance Atlas V rocket set to carry NASA's Tracking and Data Relay Satellite, TDRS-K, stands at the launch pad after leaving the Vertical Integration Facility. Liftoff for the TDRS-K is planned for Jan. 30, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1053

NASA Image and Video Library

2013-01-11

TITUSVILLE, Fla. - Inside the Astrotech payload processing facility in Titusville, Fla. near NASA’s Kennedy Space Center, the Tracking and Data Relay Satellite, TDRS-K, is being checked out prior to being encapsulated in the nose faring. Launch of the TDRS-K on the Atlas V rocket is planned for January 29, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Jim Grossmann

KSC-2013-1055

NASA Image and Video Library

2013-01-11

TITUSVILLE, Fla. - In the Astrotech payload processing facility in Titusville, Fla. near NASA’s Kennedy Space Center, a t Boeing technician checks out the Tracking and Data Relay Satellite, TDRS-K. Launch of the TDRS-K on the Atlas V rocket is planned for January 29, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Jim Grossmann

KSC-2013-1222

NASA Image and Video Library

2013-01-29

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41, the United Launch Alliance Atlas V rocket set to carry NASA's Tracking and Data Relay Satellite, TDRS-K, moves toward the launch pad after leaving the Vertical Integration Facility. Liftoff for the TDRS-K is planned for Jan. 30, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1092

NASA Image and Video Library

2013-01-16

TITUSVILLE, Fla. – A closer look at the logo painted on one half of the payload fairing that will protect NASA's Tracking and Data Relay Satellite, TDRS-K, inside the Astrotech payload processing facility in Titusville, Fla., near NASA’s Kennedy Space Center. Launch of the TDRS-K on a United Launch Alliance Atlas V rocket is planned for January 29, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. Photo credit: NASA/Frankie Martin

KSC-2013-1227

NASA Image and Video Library

2013-01-29

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41, the United Launch Alliance Atlas V rocket set to carry NASA's Tracking and Data Relay Satellite, TDRS-K, nears the launch pad after leaving the Vertical Integration Facility. Liftoff for the TDRS-K is planned for Jan. 30, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1218

NASA Image and Video Library

2013-01-29

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41, the United Launch Alliance Atlas V rocket set to carry NASA's Tracking and Data Relay Satellite, TDRS-K, moves toward the launch pad after leaving the Vertical Integration Facility. . Liftoff for the TDRS-K is planned for Jan. 30, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1059

NASA Image and Video Library

2013-01-11

TITUSVILLE, Fla. - Inside the Astrotech payload processing facility in Titusville, Fla. near NASA’s Kennedy Space Center, the Tracking and Data Relay Satellite, TDRS-K, has been checked out and awaits the arrival of the TDRS-K. Launch of the TDRS-K on the Atlas V rocket is planned for January 29, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Jim Grossmann

KSC-2013-1220

NASA Image and Video Library

2013-01-29

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41, the United Launch Alliance Atlas V rocket set to carry NASA's Tracking and Data Relay Satellite, TDRS-K, moves toward the launch pad after leaving the Vertical Integration Facility. . Liftoff for the TDRS-K is planned for Jan. 30, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1088

NASA Image and Video Library

2013-01-16

TITUSVILLE, Fla. – A closer look at the logo painted on one half of the payload fairing that will protect NASA's Tracking and Data Relay Satellite, TDRS-K, inside the Astrotech payload processing facility in Titusville, Fla., near NASA’s Kennedy Space Center. Launch of the TDRS-K on a United Launch Alliance Atlas V rocket is planned for January 29, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. Photo credit: NASA/Frankie Martin

KSC-2013-1225

NASA Image and Video Library

2013-01-29

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41, the United Launch Alliance Atlas V rocket set to carry NASA's Tracking and Data Relay Satellite, TDRS-K, nears the launch pad after leaving the Vertical Integration Facility. Liftoff for the TDRS-K is planned for Jan. 30, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1237

NASA Image and Video Library

2013-01-29

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41, the United Launch Alliance Atlas V rocket set to carry NASA's Tracking and Data Relay Satellite, TDRS-K, stands at the launch pad after leaving the Vertical Integration Facility. Liftoff for the TDRS-K is planned for Jan. 30, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1224

NASA Image and Video Library

2013-01-29

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41, the United Launch Alliance Atlas V rocket set to carry NASA's Tracking and Data Relay Satellite, TDRS-K, nears the launch pad after leaving the Vertical Integration Facility. Liftoff for the TDRS-K is planned for Jan. 30, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1229

NASA Image and Video Library

2013-01-29

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41, the United Launch Alliance Atlas V rocket set to carry NASA's Tracking and Data Relay Satellite, TDRS-K, nears the launch pad after leaving the Vertical Integration Facility. Liftoff for the TDRS-K is planned for Jan. 30, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2012-6551

NASA Image and Video Library

2012-12-19

TITUSVILLE, Fla. - Inside the Astrotech payload processing facility in Titusville, Fla. near NASA’s Kennedy Space Center, the Tracking and Data Relay Satellite, TDRS-K, is being checked out prior to being encapsulated in the nose faring. Launch of the TDRS-K on the Atlas V rocket is planned for January 29, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1231

NASA Image and Video Library

2013-01-29

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41, the United Launch Alliance Atlas V rocket set to carry NASA's Tracking and Data Relay Satellite, TDRS-K, arrives at the launch pad after leaving the Vertical Integration Facility. Liftoff for the TDRS-K is planned for Jan. 30, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2013-1233

NASA Image and Video Library

2013-01-29

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41, the United Launch Alliance Atlas V rocket set to carry NASA's Tracking and Data Relay Satellite, TDRS-K, arrives at the launch pad after leaving the Vertical Integration Facility. Liftoff for the TDRS-K is planned for Jan. 30, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2009-5068

NASA Image and Video Library

2009-08-27

CAPE CANAVERAL, Fla. – The enclosed Space Tracking and Surveillance System – Demonstrators, or STSS-Demo, spacecraft arrives on Cape Canaveral Air Force Station's Launch Pad 17-B. The STSS Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jack Pfaller

KSC-2012-6544

NASA Image and Video Library

2012-12-19

TITUSVILLE, Fla. - Technicians begin the process of removing the Tracking and Data Relay Satellite, TDRS-K, from the shipping container after arrival at the Astrotech payload processing facility in Titusville, Fla. near NASA’s Kennedy Space Center. Launch of the TDRS-K on the Atlas V rocket is planned for January 29, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2012-6542

NASA Image and Video Library

2012-12-19

TITUSVILLE, Fla. - Technicians use a crane to lift the transport container with the Tracking and Data Relay Satellite, TDRS-K, after arrival at the Astrotech payload processing facility in Titusville, Fla. near NASA’s Kennedy Space Center. Launch of the TDRS-K on the Atlas V rocket is planned for January 29, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

KSC-2012-6543

NASA Image and Video Library

2012-12-19

TITUSVILLE, Fla. - Technicians begin the process of removing the Tracking and Data Relay Satellite, TDRS-K, from the shipping container after arrival at the Astrotech payload processing facility in Titusville, Fla. near NASA’s Kennedy Space Center. Launch of the TDRS-K on the Atlas V rocket is planned for January 29, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Kim Shiflett

Space Object Query Tool

NASA Technical Reports Server (NTRS)

Phillips, Veronica J.

2017-01-01

STI is for a fact sheet on the Space Object Query Tool being created by the MDC. When planning launches, NASA must first factor in the tens of thousands of objects already in orbit around the Earth. The number of human-made objects, including nonfunctional spacecraft, abandoned launch vehicle stages, mission-related debris and fragmentation debris orbiting Earth has grown steadily since Sputnik 1 was launched in 1957. Currently, the U.S. Department of Defenses Joint Space Operations Center, or JSpOC, tracks over 15,000 distinct objects and provides data for more than 40,000 objects via its Space-Track program, found at space-track.org.

Point-ahead limitation on reciprocity tracking. [in earth-space optical link

NASA Technical Reports Server (NTRS)

Shapiro, J. H.

1975-01-01

The average power received at a spacecraft from a reciprocity-tracking transmitter is shown to be the free-space diffraction-limited result times a gain-reduction factor that is due to the point-ahead requirement. For a constant-power transmitter, the gain-reduction factor is approximately equal to the appropriate spherical-wave mutual-coherence function. For a constant-average-power transmitter, an exact expression is obtained for the gain-reduction factor.

Application of Smoothing Techniques for Tracking Maneuvering Targets. Multiple Target Tracking in Clutter: New Approaches

DTIC Science & Technology

1992-07-01

target state estimation is affected not only by the measurement noise but also by the uncertainty in the origins of the measurements. To improve the...to identify targets in the presence of anticipated background noise (including earth, lunar, star backgrounds, complicated spacecraft structures...each other. Futhermore, those frames are often degraded versions of the original scene due to blur and noise . Through the task of image registration

Architecture Study on Telemetry Coverage for Immediate Post-Separation Phase

NASA Technical Reports Server (NTRS)

Cheung, Kar-Ming; Lee, Charles H.; Kellogg, Kent H.; Stocklin, Frank J.; Zillig, David J.; Fielhauer, Karl B.

2008-01-01

This paper presents the preliminary results of an architecture study that provides continuous telemetry coverage for NASA missions for immediate post-separation phase. This study is a collaboration effort between Jet Propulsion Laboratory (JPL), Goddard Space Flight Center (GSFC), and Applied Physics Laboratory (APL). After launch when the spacecraft separated from the upper stage, the spacecraft typically executes a number of mission-critical operations prior to the deployment of solar panels and the activation of the primary communication subsystem. JPL, GSFC, and APL have similar design principle statements that require continuous coverage of mission-critical telemetry during the immediate post-separation phase. To conform to these design principles, an architecture that consists of a separate spacecraft transmitter and a robust communication network capable of tracking the spacecraft signals is needed.This paper presents the preliminary results of an architecture study that provides continuous telemetry coverage for NASA missions for immediate post-separation phase. This study is a collaboration effort between Jet Propulsion Laboratory (JPL), Goddard Space Flight Center (GSFC), and Applied Physics Laboratory (APL). After launch when the spacecraft separated from the upper stage, the spacecraft typically executes a number of mission-critical operations prior to the deployment of solar panels and the activation of the primary communication subsystem. JPL, GSFC, and APL have similar design principle statements that require continuous coverage of mission-critical telemetry during the immediate post-separation phase. To conform to these design principles, an architecture that consists of a separate spacecraft transmitter and a robust communication network capable of tracking the spacecraft signals is needed. The main results of this study are as follows: 1) At low altitude (< 10000 km) when most post-separation critical operations are executed, Earth-based network (e.g. Deep Space Network (DSN)) can only provide limited coverage, whereas space-based network (e.g. Space Network (SN)) can provide continuous coverage. 2) Commercial-off-the-shelf SN compatible transmitters are available for small satellite applications. In this paper we present the detailed coverage analysis of Earth-based and Space-based networks. We identify the key functional and performance requirements of the architecture, and describe the proposed selection criteria of the spacecraft transmitter. We conclude the paper with a proposed forward plan.

Vehicle Dynamics due to Magnetic Launch Propulsion

NASA Technical Reports Server (NTRS)

Galaboff, Zachary J.; Jacobs, William; West, Mark E.; Montenegro, Justino (Technical Monitor)

2000-01-01

The field of Magnetic Levitation Lind Propulsion (MagLev) has been around for over 30 years, primarily in high-speed rail service. In recent years, however, NASA has been looking closely at MagLev as a possible first stage propulsion system for spacecraft. This approach creates a variety of new problems that don't currently exist with the present MagLev trains around the world. NASA requires that a spacecraft of approximately 120,000 lbs be accelerated at two times the acceleration of gravity (2g's). This produces a greater demand on power over the normal MagLev trains that accelerate at around 0.1g. To be able to store and distribute up to 3,000 Mega Joules of energy in less than 10 seconds is a technical challenge. Another problem never addressed by the train industry and, peculiar only to NASA, is the control of a lifting body through the acceleration of and separation from the MagLev track. Very little is understood about how a lifting body will react with external forces, Such as wind gusts and ground effects, while being propelled along on soft springs such as magnetic levitators. Much study needs to be done to determine spacecraft control requirements as well as what control mechanisms and aero-surfaces should be placed on the carrier. Once the spacecraft has been propelled down the track another significant event takes place, the separation of the spacecraft from the carrier. The dynamics involved for both the carrier and the spacecraft are complex and coupled. Analysis of the reaction of the carrier after losing, a majority of its mass must be performed to insure control of the carrier is maintained and a safe separation of the spacecraft is achieved. The spacecraft angle of attack required for lift and how it will affect the carriage just prior to separation, along with the impacts of around effect and aerodynamic forces at ground level must be modeled and analyzed to define requirements on the launch vehicle design. Mechanisms, which can withstand the expected forces and allow the spacecraft to separate at the desired time must be developed. Modeling and analysis of the full-scale system must be developed to derive the requirements for design of the separation mechanisms. A description of several MagLev demonstrators will be presented and the testing and analysis to model the demonstrators will be included.

Design and Flight Performance of NOAA-K Spacecraft Batteries

NASA Technical Reports Server (NTRS)

Rao, Gopalakrishna M.; Chetty, P. R. K.; Spitzer, Tom; Chilelli, P.

1999-01-01

The US National Oceanic and Atmospheric Administration (NOAA) operates the Polar Operational Environmental Satellite (POES) spacecraft (among others) to support weather forecasting, severe storm tracking, and meteorological research by the National Weather Service (NWS). The latest in the POES series of spacecraft, named as NOAA-KLMNN, is in orbit and four more are in various phases of development. The NOAA-K spacecraft was launched on May 13, 1998. Each of these spacecraft carry three Nickel-Cadmium batteries designed and manufactured by Lockheed Martin. The battery, which consists of seventeen 40 Ah cells manufactured by SAFT, provides the spacecraft power during the ascent phase, orbital eclipse and when the power demand is in excess of the solar array capability. The NOAA-K satellite is in a 98 degree inclination, 7:30AM ascending node orbit. In this orbit the satellite experiences earth occultation only 25% of the year. This paper provides a brief overview of the power subsystem, followed by the battery design and qualification, the cell life cycle test data, and the performance during launch and in orbit.

Design and Flight Performance of NOAA-K Spacecraft Batteries

NASA Technical Reports Server (NTRS)

Rao, Gopalakrishna M.; Chetty, P. R. K.; Spitzer, Tom; Chilelli, P.

1998-01-01

The US National Oceanic and Atmospheric Administration (NOAA) operates the Polar Operational Environmental Satellite (POES) spacecraft (among others) to support weather forecasting, severe storm tracking, and meteorological research by the National Weather Service (NWS). The latest in the POES series of spacecraft, named as NOAA-KLMNN', one is in orbit and four more are in various phases of development. The NOAA-K spacecraft was launched on May 13, 1998. Each of these spacecraft carry three Nickel-Cadmium batteries designed and manufactured by Lockheed Martin. The battery, which consists of seventeen 40 Ah cells manufactured by SAFT, provides the spacecraft power during the ascent phase, orbital eclipse and when the power demand is in excess of the solar array capability. The NOAA-K satellite is in a 98 degree inclination, 7:30AM ascending node orbit. In this orbit the satellite experiences earth occultation only 25% of the year. This paper provides a brief overview of the power subsystem, followed by the battery design and qualification, the cell life cycle test data, and the performance during launch and in orbit.

Hardware Simulations of Spacecraft Attitude Synchronization Using Lyapunov-Based Controllers

NASA Astrophysics Data System (ADS)

Jung, Juno; Park, Sang-Young; Eun, Youngho; Kim, Sung-Woo; Park, Chandeok

2018-04-01

In the near future, space missions with multiple spacecraft are expected to replace traditional missions with a single large spacecraft. These spacecraft formation flying missions generally require precise knowledge of relative position and attitude between neighboring agents. In this study, among the several challenging issues, we focus on the technique to control spacecraft attitude synchronization in formation. We develop a number of nonlinear control schemes based on the Lyapunov stability theorem and considering special situations: full-state feedback control, full-state feedback control with unknown inertia parameters, and output feedback control without angular velocity measurements. All the proposed controllers offer absolute and relative control using reaction wheel assembly for both regulator and tracking problems. In addition to the numerical simulations, an air-bearing-based hardware-in-the-loop (HIL) system is used to verify the proposed control laws in real-time hardware environments. The pointing errors converge to 0.5{°} with numerical simulations and to 2{°} using the HIL system. Consequently, both numerical and hardware simulations confirm the performance of the spacecraft attitude synchronization algorithms developed in this study.

Space shuttle launch era spacecraft injection errors and DSN initial acquisition

NASA Technical Reports Server (NTRS)

Khatib, A. R.; Berman, A. L.; Wackley, J. A.

1981-01-01

The initial acquisition of a spacecraft by the Deep Space Network (DSN) is a critical mission event. This results from the importance of rapidly evaluating the health and trajectory of a spacecraft in the event that immediate corrective action might be required. Further, the DSN initial acquisition is always complicated by the most extreme tracking rates of the mission. The DSN initial acquisition characteristics will change considerably in the upcoming space shuttle launch era. How given injection errors at spacecraft separation from the upper stage launch vehicle (carried into orbit by the space shuttle) impact the DSN initial acquisition, and how this information can be factored into injection accuracy requirements to be levied on the Space Transportation System (STS) is addressed. The approach developed begins with the DSN initial acquisition parameters, generates a covariance matrix, and maps this covariance matrix backward to the spacecraft injection, thereby greatly simplifying the task of levying accuracy requirements on the STS, by providing such requirements in a format both familiar and convenient to STS.

Spacecraft 3D Augmented Reality Mobile App

NASA Technical Reports Server (NTRS)

Hussey, Kevin J.; Doronila, Paul R.; Kumanchik, Brian E.; Chan, Evan G.; Ellison, Douglas J.; Boeck, Andrea; Moore, Justin M.

2013-01-01

The Spacecraft 3D application allows users to learn about and interact with iconic NASA missions in a new and immersive way using common mobile devices. Using Augmented Reality (AR) techniques to project 3D renditions of the mission spacecraft into real-world surroundings, users can interact with and learn about Curiosity, GRAIL, Cassini, and Voyager. Additional updates on future missions, animations, and information will be ongoing. Using a printed AR Target and camera on a mobile device, users can get up close with these robotic explorers, see how some move, and learn about these engineering feats, which are used to expand knowledge and understanding about space. The software receives input from the mobile device's camera to recognize the presence of an AR marker in the camera's field of view. It then displays a 3D rendition of the selected spacecraft in the user's physical surroundings, on the mobile device's screen, while it tracks the device's movement in relation to the physical position of the spacecraft's 3D image on the AR marker.

Analysis of an Interplanetary Coronal Mass Ejection by a Spacecraft Radio Signal: A Case Study

NASA Astrophysics Data System (ADS)

Molera Calvés, G.; Kallio, E.; Cimo, G.; Quick, J.; Duev, D. A.; Bocanegra Bahamón, T.; Nickola, M.; Kharinov, M. A.; Mikhailov, A. G.

2017-11-01

Tracking radio communication signals from planetary spacecraft with ground-based telescopes offers the possibility to study the electron density and the interplanetary scintillation of the solar wind. Observations of the telemetry link of planetary spacecraft have been conducted regularly with ground antennae from the European Very Long Baseline Interferometry Network, aiming to study the propagation of radio signals in the solar wind at different solar elongations and distances from the Sun. We have analyzed the Mars Express spacecraft radio signal phase fluctuations while, based on a 3-D heliosphere plasma simulation, an interplanetary coronal mass ejection (ICME) crossed the radio path during one of our observations on 6 April 2015. Our measurements showed that the phase scintillation indices increased by a factor of 4 during the passage of the ICME. The method presented here confirms that the phase scintillation technique based on spacecraft signals provides information of the properties and propagation of the ICMEs in the heliosphere.

ASTER Tracks Continuing Popocatepetl Eruption

NASA Image and Video Library

2012-04-27

NASA Terra spacecraft shows Popocatepetl, the nearly 18.000-foot-high volcano about 40 miles southeast of Mexico City, continuing to spew water vapor, gas, ashes and glowing rocks from its latest eruption, which started in mid-April 2012.

NASA MISR Tracks Massive Flooding in Pakistan

NASA Image and Video Library

2010-08-18

In late July 2010, flooding caused by heavy monsoon rains began in several regions of Pakistan, including the Khyber Pakhtunkhwa, Sindh, Punjab and parts of Baluchistan. This image was acquired by NASA Terra spacecraft on August 11, 2010.

NASA Satellite Tracks Underwater Volcanic Eruption in Canary Islands

NASA Image and Video Library

2011-11-02

In July 2011, volcanic tremors began on the Island of El Hierro in the Canary Islands; by September, many tourists evacuated the resort island, fearing a volcanic eruption. This image is from NASA Terra spacecraft.

The Deep Space Atomic Clock Mission

NASA Technical Reports Server (NTRS)

Ely, Todd A.; Koch, Timothy; Kuang, Da; Lee, Karen; Murphy, David; Prestage, John; Tjoelker, Robert; Seubert, Jill

2012-01-01

The Deep Space Atomic Clock (DSAC) mission will demonstrate the space flight performance of a small, low-mass, high-stability mercury-ion atomic clock with long term stability and accuracy on par with that of the Deep Space Network. The timing stability introduced by DSAC allows for a 1-Way radiometric tracking paradigm for deep space navigation, with benefits including increased tracking via utilization of the DSN's Multiple Spacecraft Per Aperture (MSPA) capability and full ground station-spacecraft view periods, more accurate radio occultation signals, decreased single-frequency measurement noise, and the possibility for fully autonomous on-board navigation. Specific examples of navigation and radio science benefits to deep space missions are highlighted through simulations of Mars orbiter and Europa flyby missions. Additionally, this paper provides an overview of the mercury-ion trap technology behind DSAC, details of and options for the upcoming 2015/2016 space demonstration, and expected on-orbit clock performance.

Three-dimensional modeling, estimation, and fault diagnosis of spacecraft air contaminants.

PubMed

Narayan, A P; Ramirez, W F

1998-01-01

A description is given of the design and implementation of a method to track the presence of air contaminants aboard a spacecraft using an accurate physical model and of a procedure that would raise alarms when certain tolerance levels are exceeded. Because our objective is to monitor the contaminants in real time, we make use of a state estimation procedure that filters measurements from a sensor system and arrives at an optimal estimate of the state of the system. The model essentially consists of a convection-diffusion equation in three dimensions, solved implicitly using the principle of operator splitting, and uses a flowfield obtained by the solution of the Navier-Stokes equations for the cabin geometry, assuming steady-state conditions. A novel implicit Kalman filter has been used for fault detection, a procedure that is an efficient way to track the state of the system and that uses the sparse nature of the state transition matrices.

Full quaternion based finite-time cascade attitude control approach via pulse modulation synthesis for a spacecraft.

PubMed

Mazinan, A H; Pasand, M; Soltani, B

2015-09-01

In the aspect of further development of investigations in the area of spacecraft modeling and analysis of the control scheme, a new hybrid finite-time robust three-axis cascade attitude control approach is proposed via pulse modulation synthesis. The full quaternion based control approach proposed here is organized in association with both the inner and the outer closed loops. It is shown that the inner closed loop, which consists of the sliding mode finite-time control approach, the pulse width pulse frequency modulator, the control allocation and finally the dynamics of the spacecraft is realized to track the three-axis referenced commands of the angular velocities. The pulse width pulse frequency modulators are in fact employed in the inner closed loop to accommodate the control signals to a number of on-off thrusters, while the control allocation algorithm provides the commanded firing times for the reaction control thrusters in the overactuated spacecraft. Hereinafter, the outer closed loop, which consists of the proportional linear control approach and the kinematics of the spacecraft is correspondingly designed to deal with the attitude angles that are presented by quaternion vector. It should be noted that the main motivation of the present research is to realize a hybrid control method by using linear and nonlinear terms and to provide a reliable and robust control structure, which is able to track time varying three-axis referenced commands. Subsequently, a stability analysis is presented to verify the performance of the overall proposed cascade attitude control approach. To prove the effectiveness of the presented approach, a thorough investigation is presented compared to a number of recent corresponding benchmarks. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

Preliminary Operational Results of the TDRSS Onboard Navigation System (TONS) for the Terra Mission

NASA Technical Reports Server (NTRS)

Gramling, Cheryl; Lorah, John; Santoro, Ernest; Work, Kevin; Chambers, Robert; Bauer, Frank H. (Technical Monitor)

2000-01-01

The Earth Observing System Terra spacecraft was launched on December 18, 1999, to provide data for the characterization of the terrestrial and oceanic surfaces, clouds, radiation, aerosols, and radiative balance. The Tracking and Data Relay Satellite System (TDRSS) Onboard Navigation System (ONS) (TONS) flying on Terra provides the spacecraft with an operational real-time navigation solution. TONS is a passive system that makes judicious use of Terra's communication and computer subsystems. An objective of the ONS developed by NASA's Goddard Space Flight Center (GSFC) Guidance, Navigation and Control Center is to provide autonomous navigation with minimal power, weight, and volume impact on the user spacecraft. TONS relies on extracting tracking measurements onboard from a TDRSS forward-link communication signal and processing these measurements in an onboard extended Kalman filter to estimate Terra's current state. Terra is the first NASA low Earth orbiting mission to fly autonomous navigation which produces accurate results. The science orbital accuracy requirements for Terra are 150 meters (m) (3sigma) per axis with a goal of 5m (1 sigma) RSS which TONS is expected to meet. The TONS solutions are telemetered in real-time to the mission scientists along with their science data for immediate processing. Once set in the operational mode, TONS eliminates the need for ground orbit determination and allows for a smooth flow from the spacecraft telemetry to planning products for the mission team. This paper will present the preliminary results of the operational TONS solution available from Terra.

A Deep Space Orbit Determination Software: Overview and Event Prediction Capability

NASA Astrophysics Data System (ADS)

Kim, Youngkwang; Park, Sang-Young; Lee, Eunji; Kim, Minsik

2017-06-01

This paper presents an overview of deep space orbit determination software (DSODS), as well as validation and verification results on its event prediction capabilities. DSODS was developed in the MATLAB object-oriented programming environment to support the Korea Pathfinder Lunar Orbiter (KPLO) mission. DSODS has three major capabilities: celestial event prediction for spacecraft, orbit determination with deep space network (DSN) tracking data, and DSN tracking data simulation. To achieve its functionality requirements, DSODS consists of four modules: orbit propagation (OP), event prediction (EP), data simulation (DS), and orbit determination (OD) modules. This paper explains the highest-level data flows between modules in event prediction, orbit determination, and tracking data simulation processes. Furthermore, to address the event prediction capability of DSODS, this paper introduces OP and EP modules. The role of the OP module is to handle time and coordinate system conversions, to propagate spacecraft trajectories, and to handle the ephemerides of spacecraft and celestial bodies. Currently, the OP module utilizes the General Mission Analysis Tool (GMAT) as a third-party software component for highfidelity deep space propagation, as well as time and coordinate system conversions. The role of the EP module is to predict celestial events, including eclipses, and ground station visibilities, and this paper presents the functionality requirements of the EP module. The validation and verification results show that, for most cases, event prediction errors were less than 10 millisec when compared with flight proven mission analysis tools such as GMAT and Systems Tool Kit (STK). Thus, we conclude that DSODS is capable of predicting events for the KPLO in real mission applications.

Apollo 15 contamination photography

NASA Technical Reports Server (NTRS)

Naumann, R. J.

1972-01-01

The problem of optical contamination in the form of particulates in the vicinity of a spacecraft has been a source of concern for any astronomical experiment that must be performed in sunlight. This concern prompted a photographic photometric experiment on Apollo 15 to measure the brightness of the residual contamination cloud as well as the cloud produced by dumping waste water overboard. An upper limit of 10 to the minus 12.3 power B (B designates the brightness of the solar disc) was placed on the residual cloud at a 90 deg sun angle, which is comparable to the zodiacal light. The brightness of the cloud produced by the waste dump was estimated to be 10 to the minus 9.2 power B. It was observed to decrease rapidly to 10 to the -11.6 power B in minutes, then fluctuate in brightness for at least 25 minutes as additional material left the spacecraft. The cloud was observed to consist of individually resolved particle tracks estimated to be particles ranging from millimeters to centimeters in diameter in addition to a background of unresolved particles with an average diameter of 10.5 microns. Most of the tracks proceeded in straight-line paths from the dump nozzle. Several tracks violated this direction, apparently having been scattered by collisions. A few tracks appeared to have definite curvatures, which are believed to be caused by charged particle interactions.

Using The Global Positioning System For Earth Orbiter and Deep Space Network

NASA Technical Reports Server (NTRS)

Lichten, Stephen M.; Haines, Bruce J.; Young, Lawrence E.; Dunn, Charles; Srinivasan, Jeff; Sweeney, Dennis; Nandi, Sumita; Spitzmesser, Don

1994-01-01

The Global Positioning System (GPS) can play a major role in supporting orbit and trajectory determination for spacecraft in a wide range of applications, including low-Earth, high-earth, and even deep space (interplanetary) tracking.

NPS alternate techsat satellite, design project for AE-4871

NASA Technical Reports Server (NTRS)

1993-01-01

This project was completed as part of AE-4871, Advanced Spacecraft Design. The intent of the course is to provide experience in the design of all the major components in a spacecraft system. Team members were given responsibility for the design of one of the six primary subsystems: power, structures, propulsion, attitude control, telemetry, tracking and control (TT&C), and thermal control. In addition, a single member worked on configuration control, launch vehicle integration, and a spacecraft test plan. Given an eleven week time constraint, a preliminary design of each subsystem was completed. Where possible, possible component selections were also made. Assistance for this project came principally from the Naval Research Laboratory's Spacecraft Technology Branch. Specific information on components was solicited from representatives in industry. The design project centers on a general purpose satellite bus that is currently being sought by the Strategic Defense Initiative.

KSC-06pd2275

NASA Image and Video Library

2006-10-11

KENNEDY SPACE CENTER, FLA. - Inside the mobile service tower on Launch Pad 17-B at Cape Canaveral Air Force Station, workers unlatch the transportation canister segments that enclose the STEREO spacecraft. The spacecraft is being prepared for launch, scheduled for Oct. 25. STEREO stands for Solar Terrestrial Relations Observatory and comprises two spacecraft that will launch in a piggyback mode, separating after reaching the appropriate orbit. The STEREO mission is the first to take measurements of the sun and solar wind in 3-dimension. This new view will improve our understanding of space weather and its impact on the Earth. The STEREO mission is managed by Goddard. The Applied Physics Laboratory designed and built the spacecraft. The laboratory will maintain command and control of the observatories throughout the mission, while NASA tracks and receives the data, determines the orbit of the satellites, and coordinates the science results. Photo credit: NASA/Jim Grossmann

KSC-06pd2279

NASA Image and Video Library

2006-10-11

KENNEDY SPACE CENTER, FLA. - Inside the mobile service tower on Launch Pad 17-B at Cape Canaveral Air Force Station, workers begin removing the protective cover surrounding the STEREO spacecraft. The spacecraft is being prepared for launch, scheduled for Oct. 25. STEREO stands for Solar Terrestrial Relations Observatory and comprises two spacecraft that will launch in a piggyback mode, separating after reaching the appropriate orbit. The STEREO mission is the first to take measurements of the sun and solar wind in 3-dimension. This new view will improve our understanding of space weather and its impact on the Earth. The STEREO mission is managed by Goddard. The Applied Physics Laboratory designed and built the spacecraft. The laboratory will maintain command and control of the observatories throughout the mission, while NASA tracks and receives the data, determines the orbit of the satellites, and coordinates the science results. Photo credit: NASA/Jim Grossmann

KSC-06pd2261

NASA Image and Video Library

2006-10-10

KENNEDY SPACE CENTER, FLA. - At Astrotech Space Operations in Titusville, Fla., the STEREO spacecraft is being moved out of the high bay. A truck will transport the spacecraft to Launch Pad 17-B on Cape Canaveral Air Force Station where it will be lifted into the mobile service tower. STEREO stands for Solar Terrestrial Relations Observatory and comprises two spacecraft. The STEREO mission is the first to take measurements of the sun and solar wind in 3-dimension. This new view will improve our understanding of space weather and its impact on the Earth. The STEREO mission is managed by Goddard. The Applied Physics Laboratory designed and built the spacecraft. The laboratory will maintain command and control of the observatories throughout the mission, while NASA tracks and receives the data, determines the orbit of the satellites, and coordinates the science results. STEREO is expected to lift off Oct. 25. Photo credit: NASA/George Shelton

KSC-06pd2261a

NASA Image and Video Library

2006-10-10

KENNEDY SPACE CENTER, FLA. - At Astrotech Space Operations in Titusville, Fla., the transporter carrying the STEREO spacecraft is secured to the truck that will transport it to Launch Pad 17-B on Cape Canaveral Air Force Station. At the pad, the spacecraft will be lifted into the mobile service tower. STEREO stands for Solar Terrestrial Relations Observatory and comprises two spacecraft. The STEREO mission is the first to take measurements of the sun and solar wind in 3-dimension. This new view will improve our understanding of space weather and its impact on the Earth. The STEREO mission is managed by Goddard Space Flight Center. The Applied Physics Laboratory designed and built the spacecraft. The laboratory will maintain command and control of the observatories throughout the mission, while NASA tracks and receives the data, determines the orbit of the satellites, and coordinates the science results. STEREO is expected to lift off Oct. 25. Photo credit: NASA/George Shelton

KSC-06pd2276

NASA Image and Video Library

2006-10-11

KENNEDY SPACE CENTER, FLA. - Inside the mobile service tower on Launch Pad 17-B at Cape Canaveral Air Force Station, workers observe the lifting of the upper segment of the transportation canister that encloses the STEREO spacecraft. The spacecraft is being prepared for launch, scheduled for Oct. 25. STEREO stands for Solar Terrestrial Relations Observatory and comprises two spacecraft that will launch in a piggyback mode, separating after reaching the appropriate orbit. The STEREO mission is the first to take measurements of the sun and solar wind in 3-dimension. This new view will improve our understanding of space weather and its impact on the Earth. The STEREO mission is managed by Goddard. The Applied Physics Laboratory designed and built the spacecraft. The laboratory will maintain command and control of the observatories throughout the mission, while NASA tracks and receives the data, determines the orbit of the satellites, and coordinates the science results. Photo credit: NASA/Jim Grossmann

KSC-06pd2262

NASA Image and Video Library

2006-10-10

KENNEDY SPACE CENTER, FLA. - At Astrotech Space Operations in Titusville, Fla., the transporter carrying the STEREO spacecraft is attached to the truck for transportation to Launch Pad 17-B on Cape Canaveral Air Force Station. At the pad the spacecraft will be lifted into the mobile service tower. STEREO stands for Solar Terrestrial Relations Observatory and comprises two spacecraft. The STEREO mission is the first to take measurements of the sun and solar wind in 3-dimension. This new view will improve our understanding of space weather and its impact on the Earth. The STEREO mission is managed by Goddard Space Flight Center. The Applied Physics Laboratory designed and built the spacecraft. The laboratory will maintain command and control of the observatories throughout the mission, while NASA tracks and receives the data, determines the orbit of the satellites, and coordinates the science results. STEREO is expected to lift off Oct. 25. Photo credit: NASA/George Shelton

KSC-06pd2278

NASA Image and Video Library

2006-10-11

KENNEDY SPACE CENTER, FLA. - Inside the mobile service tower on Launch Pad 17-B at Cape Canaveral Air Force Station, workers begin removing the lower segment of the transportation canister that encloses the STEREO spacecraft. The spacecraft is being prepared for launch, scheduled for Oct. 25. STEREO stands for Solar Terrestrial Relations Observatory and comprises two spacecraft that will launch in a piggyback mode, separating after reaching the appropriate orbit. The STEREO mission is the first to take measurements of the sun and solar wind in 3-dimension. This new view will improve our understanding of space weather and its impact on the Earth. The STEREO mission is managed by Goddard. The Applied Physics Laboratory designed and built the spacecraft. The laboratory will maintain command and control of the observatories throughout the mission, while NASA tracks and receives the data, determines the orbit of the satellites, and coordinates the science results. Photo credit: NASA/Jim Grossmann

KSC-06pd2280

NASA Image and Video Library

2006-10-11

KENNEDY SPACE CENTER, FLA. - Inside the mobile service tower on Launch Pad 17-B at Cape Canaveral Air Force Station, workers begin removing the protective cover surrounding the STEREO spacecraft. The spacecraft is being prepared for launch, scheduled for Oct. 25. STEREO stands for Solar Terrestrial Relations Observatory and comprises two spacecraft that will launch in a piggyback mode, separating after reaching the appropriate orbit. The STEREO mission is the first to take measurements of the sun and solar wind in 3-dimension. This new view will improve our understanding of space weather and its impact on the Earth. The STEREO mission is managed by Goddard. The Applied Physics Laboratory designed and built the spacecraft. The laboratory will maintain command and control of the observatories throughout the mission, while NASA tracks and receives the data, determines the orbit of the satellites, and coordinates the science results. Photo credit: NASA/Jim Grossmann

Nutation and precession control of the High Energy Solar Physics (HESP) satellite

NASA Technical Reports Server (NTRS)

Jayaraman, C. P.; Robertson, B. P.

1993-01-01

The High Energy Solar Physics (HESP) spacecraft is an intermediate class satellite proposed by NASA to study solar high-energy phenomena during the next cycle of high solar activity in the 1998 to 2005 time frame. The HESP spacecraft is a spinning satellite which points to the sun with stringent pointing requirements. The natural dynamics of a spinning satellite includes an undesirable effect: nutation, which is due to the presence of disturbances and offsets of the spin axis from the angular momentum vector. The proposed Attitude Control System (ACS) attenuates nutation with reaction wheels. Precessing the spacecraft to track the sun in the north-south and east-west directions is accomplished with the use of torques from magnetic torquer bars. In this paper, the basic dynamics of a spinning spacecraft are derived, control algorithms to meet HESP science requirements are discussed and simulation results to demonstrate feasibility of the ACS concept are presented.

Vehicle Tracking System using Nanotechnology Satellites and Tags

NASA Technical Reports Server (NTRS)

Lorenzini, Dino A.; Tubis, Chris

1995-01-01

This paper describes a joint project to design, develop, and deploy a satellite based tracking system incorporating micro-nanotechnology components. The system consists of a constellation of 'nanosats', a satellite command station and data collection sites, and a large number of low-cost electronic 'tags'. Both government and commercial applications are envisioned for the satellite based tracking system. The projected low price for the tracking service is made possible by the lightweight nanosats and inexpensive electronic tags which use high production volume single chip transceivers and microprocessor devices. The nanosat consists of a five inch aluminum cube with body mounted solar panels (GaAs solar cells) on all six faces. A UHF turnstile antenna and a simple, spring release mechanism complete the external configuration of the spacecraft.

GPS Receiver On-Orbit Performance for the GOES-R Spacecraft

NASA Technical Reports Server (NTRS)

Winkler, Stephen; Ramsey, Graeme; Frey, Charles; Chapel, Jim; Chu, Donald; Freesland, Douglas; Krimchansky, Alexander; Concha, Marco

2017-01-01

This paper evaluates the on-orbit performance of the first civilian operational use of a Global Positioning System Receiver (GPSR) at a geostationary orbit (GEO). The GPSR is on-board the newly launched Geostationary Operational Environmental Satellite (GOES-R). GOES-R is the first of four next generation GEO weather satellites for NOAA, now in orbit GOES-R is formally identified as GOES-16. Among the pioneering technologies required to support its improved spatial, spectral and temporal resolution is a GPSR. The GOES-16 GPSR system is a new design that was mission critical and therefore received appropriate scrutiny. As ground testing of a GPSR for GEO can only be done by simulations with numerous assumptions and approximations regarding the current GPS constellation, this paper reveals what performance can be achieved in using on orbit data. Extremely accurate orbital position is achieved using GPS navigation at GEO. Performance results are shown demonstrating compliance with the1007575 meter and 6 cms radial/in-track/cross-track orbital position and velocity accuracy requirements of GOES-16. The aforementioned compliance includes station-keeping and momentum management maneuvers, contributing to no observational outages. This performance is achieved by a completely new system design consisting of a unique L1 GEOantenna, low-noise amplifier (LNA) assembly and a 12 channel GPSR capable of tracking the edge of the main beam and the side lobes of the GPS L1 signals. This paper presents the definitive answer that the GOES-16 GPSR solution exceeds all performance requirements tracking up to 12 satellites and achieving excellent carrier-to-noise density (C/N0). Additionally, these performance results show the practicality of this approach. This paper makes it clear that all future GEO Satellites should consider the addition of a GPSR in their spacecraft design, otherwise they may be sacrificing spacecraft capabilities and accuracy along with incurring increased and continual demand on ground support.

Hardware test program for evaluation of baseline range/range rate sensor concept

NASA Technical Reports Server (NTRS)

Pernic, E.

1985-01-01

The test program Phase II effort provides additional design information in terms of range and range rate (R/R) sensor performance when observing and tracking a typical spacecraft target. The target used in the test program was a one-third scale model of the Hubble Space Telescope (HST) available at the MSFC test site where the tests were performed. A modified Bendix millimeter wave radar served as the R/R sensor test bed for evaluation of range and range rate tracking performance, and generation of radar signature characteristics of the spacecraft target. A summary of program test results and conclusions are presented along with detailed description of the Bendix test bed radar with accompaning instrumentation. The MSFC test site and facilities are described. The test procedures used to establish background levels, and the calibration procedures used in the range accuracy tests and RCS (radar cross section) signature measurements, are presented and a condensed version of the daily log kept during the 5 September through 17 September test period is also presented. The test program results are given starting with the RCS signature measurements, then continuing with range measurement accuracy test results and finally the range and range rate tracking accuracy test results.

The minitrack tracking function description, volume 1

NASA Technical Reports Server (NTRS)

Englar, T. S., Jr.; Mango, S. A.; Roettcher, C. A.; Watters, D. L.

1973-01-01

The treatment of tracking data by the Minitrack system is described from the transmission of the nominal 136-MHz radio beacon energy from a satellite and the reception of this signal by the interferometer network through the ultimate derivation of the direction cosines (the angular coordinates of the vector from the tracking station to the spacecraft) as a function of time. Descriptions of some of the lesser-known functions operating on the system, such as the computer preprocessing program, are included. A large part of the report is devoted to the preprocessor, which provides for the data compression, smoothing, calibration correction, and ambiguity resolution of the raw interferometer phase tracking measurements teletyped from each of the worldwide Minitrack tracking stations to the central computer facility at Goddard Space Flight Center. An extensive bibliography of Minitrack hardware and theory is presented.

Gravity Recovery and Interior Laboratory (GRAIL) Mission: Status at the Initiation of the Science Mapping Phase

NASA Technical Reports Server (NTRS)

Zuber, Maria T.; Smith, David E.; Asmar, Sami W.; Alomon; Konopliv, Alexander S.; Lemoine, Frank G.; Melosh, H. Jay; Neumann, Gregory A.; Phillips. Roger J.; Solomon, Sean C.;

A new scheme for processing noisy startracker measurements in spacecraft attitude determination systems

NASA Technical Reports Server (NTRS)

Polites, M. E.

1991-01-01

This paper presents a new approach to processing noisy startracker measurements in spacecraft attitude determination systems. It takes N measurements in each T-second interval and combines them to produce tracker outputs that are estimates of star position at the end of each interval, when the tracker outputs become available. This is an improvement over the standard method, measurement averaging, which generates outputs that are estimates of the average position of the star over each interval. This new scheme is superior to measurement averaging when the spacecraft has some rotation rate as in target tracking or earth pointing. Also, it is not just limited to startracker, but has potential application wherever measurement averaging of sensor outputs is used.

Precorrection concepts for mobile terminals with processing satellites

NASA Astrophysics Data System (ADS)

Nakamoto, F. S.; Oreilly, M. P.; Wolfson, C. R.

It is pointed out that when the spacecraft must process a large number of users simultaneously, it becomes impractical for it to acquire and track each uplink signal. A solution is for the terminals to precorrect their uplink transmissions so that they reach the spacecraft in time and frequency synchronism with the spacecraft receiver. Two dimensions of precorrection, namely time and frequency, are addressed. Precorrection approaches are classified as open loop, pseudo-open loop, or pseudo-closed loop. Performance relationships are established, and the applicability, requirements, advantages, and disadvantages of each class are discussed. It is found that since time and frequency precorrection have opposite sensitivities to the frequency hopping rate, different classes will often be adopted for the two dimensions.

Shuttle communication and tracking systems signal design and interface compatibility analysis

NASA Technical Reports Server (NTRS)

1986-01-01

Various options for the Dedicated Payload Communication Link (DPCL) were evaluated. Specific subjects addressed include: payload to DPCL power transfer in the proximity of the payload, DPCL antenna pointing considerations, and DPCL transceiver implementations which can be mounted on the deployed antenna boom. Additional analysis of the Space Telescope performance was conducted. The feasibility of using the Global Positioning System (GPS) for attitude determination and control for large spacecraft was examined. The objective of the Shuttle Orbiter Radar Test and Evaluation (SORTE) program was to quantify the Ku-band radar tracking accuracy using White Sands Missile Range (WSMR) radar and optical tracking equipment, with helicopter and balloon targets.

KSC-2009-5225

NASA Image and Video Library

2009-09-25

CAPE CANAVERAL, Fla. – The United Launch Alliance Delta II rocket carrying the Space Tracking and Surveillance System - Demonstrator, or STSS-Demo, spacecraft leaps into the sky from Launch Pad 17-B at Cape Canaveral Air Force Station. STSS-Demo was launched at 8:20:22 a.m. EDT by NASA for the U.S. Missile Defense Agency. The STSS-Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. Photo credit: NASA/Sandra Joseph- Kevin O'Connell

KSC-2009-5221

NASA Image and Video Library

2009-09-25

CAPE CANAVERAL, Fla. – The United Launch Alliance Delta II rocket with Space Tracking and Surveillance System - Demonstrator, or STSS-Demo, spacecraft leaps from Launch Pad 17-B at Cape Canaveral Air Force Station amid clouds of smoke. STSS-Demo was launched at 8:20:22 a.m. EDT by NASA for the U.S. Missile Defense Agency. The STSS-Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. Photo credit: NASA/Sandra Joseph- Kevin O'Connell

KSC-2009-5220

NASA Image and Video Library

2009-09-25

CAPE CANAVERAL, Fla. – The United Launch Alliance Delta II rocket with Space Tracking and Surveillance System - Demonstrator, or STSS-Demo, spacecraft aboard races into the sky leaving a trail of fire and smoke after liftoff from Launch Pad 17-B at Cape Canaveral Air Force Station. It was launched by NASA for the U.S. Missile Defense Agency at 8:20:22 a.m. EDT. The STSS-Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. Photo credit: NASA/Alan Ault

KSC-2009-5067

NASA Image and Video Library

2009-08-27

CAPE CANAVERAL, Fla. – The enclosed Space Tracking and Surveillance System – Demonstrators, or STSS-Demo, spacecraft leaves the Astrotech payload processing facility on its way to Cape Canaveral Air Force Station's Launch Pad 17-B. The STSS Demo is a space-based sensor component of a layered Ballistic Missile Defense System designed for the overall mission of detecting, tracking and discriminating ballistic missiles. STSS is capable of tracking objects after boost phase and provides trajectory information to other sensors. It will be launched by NASA for the Missile Defense Agency between 8 and 8:58 a.m. EDT Sept. 18. Approved for Public Release 09-MDA-04886 (10 SEPT 09) Photo credit: NASA/Jack Pfaller

KSC-2013-1058

NASA Image and Video Library

2013-01-11

TITUSVILLE, Fla. - In the Astrotech payload processing facility in Titusville, Fla. near NASA’s Kennedy Space Center, the payload faring for the Tracking and Data Relay Satellite, TDRS-K, has been checked out and awaits the arrival of the TDRS-K. Launch of the TDRS-K on the Atlas V rocket is planned for January 29, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Jim Grossmann

KSC-2013-1040

NASA Image and Video Library

2013-01-05

CAPE CANAVERAL, Fla. -- At Cape Canaveral Air Force Station's Space Launch Complex 41 in Florida, United Launch Alliance technicians support operations to lift the Centaur stage for mating to the Atlas V rocket that will carry the Tracking and Data Relay Satellite, TDRS-K, into orbit. Launch of the TDRS-K on the Atlas V rocket is planned for January 29, 2013. The TDRS-K spacecraft is part of the next-generation series in the Tracking and Data Relay Satellite System, a constellation of space-based communication satellites providing tracking, telemetry, command and high-bandwidth data return services. For more information, visit http://www.nasa.gov/mission_pages/tdrs/index.html Photo credit: NASA/Charisse Nahser