Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Configuration Control”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1993

Motion control of 7-DOF arms - The configuration control approach

Graphics simulation and real-time implementation of configuration control schemes for a redundant 7-DOF Robotics Research arm are described. The arm kinematics and motion control schemes are described briefly. This is followed by a description of a graphics simulation environment for 7-DOF arm control on the Silicon Graphics IRIS Workstation. Computer simulation results are presented to demonstrate elbow control, collision avoidance, and optimal joint movement as redundancy resolution goals. The laboratory setup for experimental validation of motion control of the 7-DOF Robotics Research arm is then described. The configuration control approach is implemented on a Motorola-68020/VME-bus-based real-time controller, with elbow positioning for redundancy resolution. Experimental results demonstrate the efficacy of configuration control for real-time control.

Seraji, Homayoun↗
NASA NTRS1993

More Uses For Configuration Control Of Robots

Two papers present theoretical studies of older and newer uses for configuration control. Configuration control described in "Increasing the Dexterity of Redundant Robots" (NPO-17801) and "Redundant Robot Can Avoid Obstacles" (NPO-17852). One paper "Configuration Control of 7 DOF Arms" reviews these concepts, then applies them to commercial robotic arm having seven revolute joints corresponding to those of human arm. Other paper "New Goals for Redundancy Resolution Using Configuration Control" addresses use of redundant degrees of freedom to optimize dynamical instead of kinematical aspects of performance.

Seraji, Homayoun↗
NASA NTRS1981

SEPAC software configuration control plan and procedures, revision 1

SEPAC Software Configuration Control Plan and Procedures are presented. The objective of the software configuration control is to establish the process for maintaining configuration control of the SEPAC software beginning with the baselining of SEPAC Flight Software Version 1 and encompass the integration and verification tests through Spacelab Level IV Integration. They are designed to provide a simplified but complete configuration control process. The intent is to require a minimum amount of paperwork but provide total traceability of SEPAC software.

Source record↗
NASA NTRS1984

Optimal cooperative control synthesis applied to a control-configured aircraft

A multivariable control augmentation synthesis method is presented that is intended to enable the designer to directly optimize pilot opinion rating of the augmented system. The approach involves the simultaneous solution for the augmentation and predicted pilot's compensation via optimal control techniques. The methodology is applied to the control law synthesis for a vehicle similar to the AFTI F16 control-configured aircraft. The resulting dynamics, expressed in terms of eigenstructure and time/frequency responses, are presented with analytical predictions of closed loop tracking performance, pilot compensation, and other predictors of pilot acceptance.

Schmidt, D. K.↗
NASA NTRS1989

Case studies in configuration control for redundant robots

A simple approach to configuration control of redundant robots is presented. The redundancy is utilized to control the robot configuration directly in task space, where the task will be performed. A number of task-related kinematic functions are defined and combined with the end-effector coordinates to form a set of configuration variables. An adaptive control scheme is then utilized to ensure that the configuration variables track the desired reference trajectories as closely as possible. Simulation results are presented to illustrate the control scheme. The scheme has also been implemented for direct online control of a PUMA industrial robot, and experimental results are presented. The simulation and experimental results validate the configuration control scheme for performing various realistic tasks.

Seraji, H.↗
NASA NTRS1983

PDSS configuration control plan and procedures

The payload development support system (PDSS) configuration control plan and procedures are presented. These plans and procedures establish the process for maintaining configuration control of the PDSS system, especially the Spacelab experiment interface device's (SEID) RAU, HRM, and PDI interface simulations and the PDSS ECOS DEP Services simulation. The plans and procedures as specified are designed to provide a simplified but complete configuration control process. The intent is to require a minimum amount of paperwork but provide total traceability of PDSS during experiment test activities.

Source record↗
NASA NTRS1990

Aeropropulsion facilities configuration control: Procedures manual

Lewis Research Center senior management directed that the aeropropulsion facilities be put under configuration control. A Configuration Management (CM) program was established by the Facilities Management Branch of the Aeropropulsion Facilities and Experiments Division. Under the CM program, a support service contractor was engaged to staff and implement the program. The Aeronautics Directorate has over 30 facilities at Lewis of various sizes and complexities. Under the program, a Facility Baseline List (FBL) was established for each facility, listing which systems and their documents were to be placed under configuration control. A Change Control System (CCS) was established requiring that any proposed changes to FBL systems or their documents were to be processed as per the CCS. Limited access control of the FBL master drawings was implemented and an audit system established to ensure all facility changes are properly processed. This procedures manual sets forth the policy and responsibilities to ensure all key documents constituting a facilities configuration are kept current, modified as needed, and verified to reflect any proposed change. This is the essence of the CM program.

Lavelle, James J.↗
NASA NTRS1993

Configuration-Control Scheme Copes With Singularities

Improved configuration-control scheme for robotic manipulator having redundant degrees of freedom suppresses large joint velocities near singularities, at expense of small trajectory errors. Provides means to enforce order of priority of tasks assigned to robot. Basic concept of configuration control of redundant robot described in "Increasing The Dexterity Of Redundant Robots" (NPO-17801).

Seraji, Homayoun↗
NASA NTRS1989

Configuration control of redundant manipulators - Theory and implementation

A simple approach for controlling the manipulator configuration over the entire motion is presented, based on augmentation of the manipulator forward kinematics. User-defined kinematic functions and the end-effector Cartesian coordinates are combined to form a set of task-related configuration variables as generalized coordinates for the manipulator. A task-based adaptive scheme is then utilized to control the configuration variables and achieve tracking of the desired reference trajectories. This achieves the desired end-effector motion while utilizing redundancy to achieve any additional task. Simulation results for a direct-drive two-link arm are given to illustrate the proposed control scheme. The scheme has also been implemented for real-time control of three links of a PUMA 560 industrial robot. The simulation and experimental results validate the configuration control scheme and demonstrate its capabilities for performing various realistic tasks.

Seraji, Homayoun↗
NASA NTRS1971

SFOF configuration control

Space Flight Operations Facility Configuration Control System for management control purposes

Carter, K. R.↗
NASA NTRS1991

Method and apparatus for configuration control of redundant robots

A method and apparatus to control a robot or manipulator configuration over the entire motion based on augmentation of the manipulator forward kinematics is disclosed. A set of kinematic functions is defined in Cartesian or joint space to reflect the desirable configuration that will be achieved in addition to the specified end-effector motion. The user-defined kinematic functions and the end-effector Cartesian coordinates are combined to form a set of task-related configuration variables as generalized coordinates for the manipulator. A task-based adaptive scheme is then utilized to directly control the configuration variables so as to achieve tracking of some desired reference trajectories throughout the robot motion. This accomplishes the basic task of desired end-effector motion, while utilizing the redundancy to achieve any additional task through the desired time variation of the kinematic functions. The present invention can also be used for optimization of any kinematic objective function, or for satisfaction of a set of kinematic inequality constraints, as in an obstacle avoidance problem. In contrast to pseudoinverse-based methods, the configuration control scheme ensures cyclic motion of the manipulator, which is an essential requirement for repetitive operations. The control law is simple and computationally very fast, and does not require either the complex manipulator dynamic model or the complicated inverse kinematic transformation. The configuration control scheme can alternatively be implemented in joint space.

Seraji, Homayoun↗
NASA NTRS1976

An analytical study of turbulence responses, including horizontal-tail loads, of a control-configured vehicle with relaxed static stability

A static stability augmentation system (SSAS) with angle-of-attack, pitch-rate, and forward-speed feedback is used to stabilize control-configured rigid vehicles with relaxed static stability. Airplane configurations include a baseline configuration and two representative control-configured vehicle configurations. The first statically unstable configuration has baseline geometry and an aft center of gravity; the second statically unstable configuration has reduced tail length and area and a forward neutral point. Stability, flying-qualities, and maneuverability requirements are imposed on the airplane-SSAS systems. Turbulence responses of the rigid airframe and tail loads are examined in terms of configuration changes for a given control law and in terms of control law changes for a given configuration.

Perry, B., III↗
NASA NTRS1990

Improved configuration control for redundant robots

This article presents a singularity-robust task-prioritized reformulation of the configuration control scheme for redundant robot manipulators. This reformulation suppresses large joint velocities near singularities, at the expense of small task trajectory errors. This is achieved by optimally reducing the joint velocities to induce minimal errors in the task performance by modifying the task trajectories. Furthermore, the same framework provides a means for assignment of priorities between the basic task of end-effector motion and the user-defined additional task for utilizing redundancy. This allows automatic relaxation of the additional task constraints in favor of the desired end-effector motion, when both cannot be achieved exactly. The improved configuration control scheme is illustrated for a variety of additional tasks, and extensive simulation results are presented.

Seraji, H.↗
NASA NTRS1976

B-52 control configured vehicles: Flight test results

Recently completed B-52 Control Configured Vehicles (CCV) flight testing is summarized, and results are compared to analytical predictions. Results are presented for five CCV system concepts: ride control, maneuver load control, flutter mode control, augmented stability, and fatigue reduction. Test results confirm analytical predictions and show that CCV system concepts achieve performance goals when operated individually or collectively.

Arnold, J. I.↗
NASA NTRS1976

Design of a control configured tanker aircraft

The benefits that accrue from using control configured vehicle (CCV) concepts were examined along with the techniques for applying these concepts to an advanced tanker aircraft design. Reduced static stability (RSS) and flutter mode control (FMC) were the two primary CCV concepts used in the design. The CCV tanker was designed to the same mission requirements specified for a conventional tanker design. A seven degree of freedom mathematical model of the flexible aircraft was derived and used to synthesize a lateral stability augmentation system (SAS), a longitudinal control augmentation system (CAS), and a FMC system. Fatigue life and cost analyses followed the control system synthesis, after which a comparative evaluation of the CCV and conventional tankers was made. This comparison indicated that the CCV weight and cost were lower but that, for this design iteration, the CCV fatigue life was shorter. Also, the CCV crew station acceleration was lower, but the acceleration at the boom operator station was higher relative to the corresponding conventional tanker. Comparison of the design processes used in the CCV and conventional design studies revealed that they were basically the same.

Walker, S. A.↗
NASA NTRS1976

Handling qualities requirements for control configured vehicles

The potential effects of fly by wire and control configured vehicle concepts on flying qualities are considered. Failure mode probabilities and consequences, controllability, and dynamics of highly augmented aircraft are among the factors discussed in terms of design criteria.

Woodcock, R. J.↗