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NASA NTRS1987

Orbital navigation, docking and obstacle avoidance as a form of three dimensional model-based image understanding

Range imagery from a laser scanner can be used to provide sufficient information for docking and obstacle avoidance procedures to be performed automatically. Three dimensional model-based computer vision algorithms in development can perform these tasks even with targets which may not be cooperative (that is, objects without special targets or markers to provide unambiguous location points). Roll, pitch and yaw of the vehicle can be taken into account as image scanning takes place, so that these can be corrected when the image is converted from egocentric to world coordinates. Other attributes of the sensor, such as the registered reflectence and texture channels, provide additional data sources for algorithm robustness. Temporal fusion of sensor immages can take place in the work coordinate domain, allowing for the building of complex maps in three dimensional space.

Beyer, J.↗

NASA NTRS1988

Orbital navigation, docking and obstacle avoidance as a form of three dimensional model-based image understanding

Range imagery from a laser scanner can be used to provide sufficient information for docking and obstacle avoidance procedures to be performed automatically. Three dimensional model-based computer vision algorithms in development can perform these tasks even with targets which may not be cooperative (that is, objects without special targets or markers to provide unambiguous points). Role, pitch, and yaw of a vehicle can be taken into account as image scanning takes place, so that these can be correlated when the image is converted from egocentric to world coordinated. Other attributes of the sensor, such as the registered reflectance and texture channels, provide additional data sources for algorithm robustness.

Beyer, J.↗

NASA NTRS1988

OMV docking simulator

The Boeing Orbital Maneuvering Vehicle (OMV) Docking and Proximity Operation System (DAPOS) was completed. The system constructed involves the use of four separate processors. Appropriate software was developed that drives each of these four processors. The hand controller logic coordinates all the activities in the control station, and communicates with the OMV mathematical model. The state vector generated by the model is in turn transmitted to the control station as well as the POLY 2000 (via the ALCYON host computer) for real time graphics generation. The OMV characteristics are stored in a data file which may be easily updated and modified without disturbing the software, thereby making the system very flexible. The current system supports two types of hand controllers. The system was flown by several volunteers, some of whom are airplane pilots. A user manual is also enclosed.

Teoh, W.↗

NASA NTRS1989

Alignment System For Docking Control

Concept for alignment of vehicle approaching station based on generation of coherent, polarized light or microwave beam by station and measurement of beam propagation and polarization axes by vehicle. Intended for use in docking of spacecraft in flight and in robotics. Conical and corner-cube reflectors on vehicle disperse portions of incident light beam to sensors on vehicle and station, respectively. Station uses return signal for ranging and tracking. Known mathematical relationship among direction of beam and positions of reflected light on photodetector arrays used to calculate orientation of vehicle.

Iwasaki, Richard S.↗

NASA NTRS1988

Target acquisition and track in the laser docking sensor

A sensor designed to aid in the docking of spacecraft is under development for NASA. This sensor uses three lasers to track the prospective target and to determine the required parameters necessary to calculate the ideal approach maneuver. The system combines the inputs from several sensors, including polarization, continuous tone DME, and a CID to achieve the desired results.

Clowes, Ted J.↗

NASA NTRS1990

Pathfinder autonomous rendezvous and docking project

Capabilities are being developed and demonstrated to support manned and unmanned vehicle operations in lunar and planetary orbits. In this initial phase, primary emphasis is placed on definition of the system requirements for candidate Pathfinder mission applications and correlation of these system-level requirements with specific requirements. The FY-89 activities detailed are best characterized as foundation building. The majority of the efforts were dedicated to assessing the current state of the art, identifying desired elaborations and expansions to this level of development and charting a course that will realize the desired objectives in the future. Efforts are detailed across all work packages in developing those requirements and tools needed to test, refine, and validate basic autonomous rendezvous and docking elements.

Lamkin, Stephen↗

NASA NTRS1992

Measurement of performance using acceleration control and pulse control in simulated spacecraft docking operations

Nine commercial airline pilots served as test subjects in a study to compare acceleration control with pulse control in simulated spacecraft maneuvers. Simulated remote dockings of an orbital maneuvering vehicle (OMV) to a space station were initiated from 50, 100, and 150 meters along the station's -V-bar (minus velocity vector). All unsuccessful missions were reflown. Five way mixed analysis of variance (ANOVA) with one between factor, first mode, and four within factors (mode, bloch, range, and trial) were performed on the data. Recorded performance measures included mission duration and fuel consumption along each of the three coordinate axes. Mission duration was lower with pulse mode, while delta V (fuel consumption) was lower with acceleration mode. Subjects used more fuel to travel faster with pulse mode than with acceleration mode. Mission duration, delta V, X delta V, Y delta V., and Z delta V all increased with range. Subjects commanded the OMV to 'fly' at faster rates from further distances. These higher average velocities were paid for with increased fuel consumption. Asymmetrical transfer was found in that the mode transitions could not be predicted solely from the mission duration main effect. More testing is advised to understand the manual control aspects of spaceflight maneuvers better.

Brody, Adam R.↗

NASA NTRS1990

Autonomous Rendezvous and Docking Conference, volume 2

Autonomous Rendezvous and Docking (ARD) will be a requirement for future space programs. Clear examples include satellite servicing, repair, recovery, and reboost in the near term, and the longer range lunar and planetary exploration programs. ARD will permit more aggressive unmanned space activities, while providing a valuable operational capability for manned missions. The purpose of the conference is to identify the technologies required for an on-orbit demonstration of ARD, assess the maturity of those technologies, and provide the necessary insight for a quality assessment of programmatic management, technical, schedule, and cost risks.

Source record↗

NASA NTRS1990

Autonomous Rendezvous and Docking Conference, volume 1

This document consists of the presentation submitted at the Autonomous Rendezvous and Docking (ARD) Conference. It contains three volumes: ARD hardware technology; ARD software technology; and ARD operations. The purpose of this conference is to identify the technologies required for an on orbit demonstration of the ARD, assess the maturity of these technologies, and provide the necessary insight for a quality assessment of the programmatic management, technical, schedule, and cost risks.

Source record↗

NASA NTRS1990

Autonomous Rendezvous and Docking Conference, volume 3

This document consists of the presentation submitted at the Autonomous Rendezvous and Docking (ARD) Conference. The document contains three volumes: ARD hardware technology; ARD software technology; and ARD operations. The purpose of this conference is to identify the technologies required for an on orbit demonstration of ARD, assess the maturity of these technologies, and provide the necessary insight for a quality assessment of programmatic management, technical, schedule, and cost risks.

Source record↗

NASA NTRS1992

Application of fuzzy logic-neural network based reinforcement learning to proximity and docking operations

As part of the Research Institute for Computing and Information Systems (RICIS) activity, the reinforcement learning techniques developed at Ames Research Center are being applied to proximity and docking operations using the Shuttle and Solar Max satellite simulation. This activity is carried out in the software technology laboratory utilizing the Orbital Operations Simulator (OOS). This interim report provides the status of the project and outlines the future plans.

Jani, Yashvant↗

NASA NTRS1991

Logistics and operations implications of manual control of spacecraft docking maneuvers

The implications of logistics and operations on the manual control of spacecraft docking are discussed. The results of simulation studies to investigate fuel and time cost tradeoffs are reviewed and discussed. Comparisons of acceleration control and pulse control are presented to evaluate the effects of astronauts being instructed to use pulse mode for fuel conservation. The applications of the findings to moon and Mars missions are addressed.

Brody, Adam R.↗

NASA NTRS1992

Application of neural networks to autonomous rendezvous and docking of space vehicles

NASA-Marshall has investigated the feasibility of numerous autonomous rendezvous and docking (ARD) candidate techniques. Neural networks have been studied as a viable basis for such systems' implementation, due to their intrinsic representation of such nonlinear functions as those for which analytical solutions are either difficult or nonexistent. Neural networks are also able to recognize and adapt to changes in their dynamic environment, thereby enhancing redundancy and fault tolerance. Outstanding performance has been obtained from ARD azimuth, elevation, and roll networks of this type.

Dabney, Richard W.↗

NASA NTRS1991

Demonstration of automated proximity and docking technologies

An autodock was demonstrated using straightforward techniques and real sensor hardware. A simulation testbed was established and validated. The sensor design was refined with improved optical performance and image processing noise mitigation techniques, and the sensor is ready for production from off-the-shelf components. The autonomous spacecraft architecture is defined. The areas of sensors, docking hardware, propulsion, and avionics are included in the design. The Guidance Navigation and Control architecture and requirements are developed. Modular structures suitable for automated control are used. The spacecraft system manager functions including configuration, resource, and redundancy management are defined. The requirements for autonomous spacecraft executive are defined. High level decisionmaking, mission planning, and mission contingency recovery are a part of this. The next step is to do flight demonstrations. After the presentation the following question was asked. How do you define validation? There are two components to validation definition: software simulation with formal and vigorous validation, and hardware and facility performance validated with respect to software already validated against analytical profile.

Anderson, Robert L.↗

NASA NTRS1991

An autonomous rendezvous and docking system using cruise missile technology

In November 1990 General Dynamics demonstrated an AR&D system for members of the Strategic Avionics Technology Working Group. This simulation utilized prototype hardware derived from the Cruise Missile and Centaur avionics systems. The object of this proof of concept demonstration was to show that all the accuracy, reliability, and operational requirements established for a spacecraft to dock with Space Station Freedom could be met by the proposed AR&D system.

Jones, ED↗

NASA NTRS1991

Soviet automated rendezvous and docking system overview

The Soviets have been performing automated rendezvous and docking for many years. This paper will present an overview and brief history of the Soviet AR&D system, based on the open literature and publicly available sources.

Hinman, Elaine M.↗

NASA NTRS1991

An overview of autonomous rendezvous and docking system technology development at General Dynamics

The Centaur avionics suite is undergoing a dramatic modernization for the commercial, DoD Atlas and Titan programs. The system has been upgraded to the current state-of-the-art in ring laser gyro inertial sensors and Mil-Std-1750A processor technology. The Cruise Missile avionic system has similarly been evolving for many years. Integration of GPS into both systems has been underway for over five years with a follow-on cruise missile system currently in flight test. Rendezvous and Docking related studies have been conducted for over five years in support of OMV, CTV, and Advanced Upper Stages, as well as several other internal IR&D's. The avionics system and AR&D simulator demonstrated to the SATWG in November 1990 has been upgraded considerably under two IR&D programs in 1991. The Centaur modern avionics system is being flown in block upgrades which started in July of 1990. The Inertial Navigation Unit will fly in November of 1991. The Cruise Missile avionics systems have been fully tested and operationally validated in combat. The integrated AR&D system for space vehicle applications has been under development and testing since 1990. A Joint NASA / GD ARD&L System Test Program is currently being planned to validate several aspects of system performance in three different NASA test facilities in 1992.

Kuenzel, Fred↗

NASA NTRS1991

Six degree of freedom simulation system for evaluating automated rendezvous and docking spacecraft

Future logistics supply and servicing vehicles such as cargo transfer vehicles (CTV) must have full 6 degree of freedom (6DOF) capability in order to perform requisite rendezvous, proximity operations, and capture operations. The design and performance issues encountered when developing a 6DOF maneuvering spacecraft are very complex with subtle interactions which are not immediately obvious or easily anticipated. In order to deal with these complexities and develop robust maneuvering spacecraft designs, a simulation system and associated family of tools are used at TRW for generating and validating spacecraft performance requirements and guidance algorithms. An overview of the simulator and tools is provided. These are used by TRW for autonomous rendezvous and docking research projects including CTV studies.

Rourke, Kenneth H.↗