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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.
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Earth reflected solar radiation and stability of satellite thermal control coatings, noting intensity distribution shifting toward UV region and coatings degradation rate
Wind tunnel evaluation of Apache model aerodynamic stability and control characteristics
Design and tests of Lunar Orbiter guidance and control systems
Stabilization and control systems for reentry vehicle
Neighboring optimal feedback control of multi-input nonlinear dynamic systems
Computerized performance evaluation of Apollo thrust vector digital autopilot control system
Twin gyro coupling system with compensation and nonlinear control for satellite attitude stabilization
Mechanical and nonmechanical controls for earth and space storable propellants for liquid rocket propulsion
This design survey summarizes the history of the Orbiting Geophysical Observatories' (OGO) Attitude Control Subsystem (ACS) from the proposal phase through current flight experience. Problems encountered in design, fabrication, test, and on orbit are discussed. It is hoped that the experiences of the OGO program related here will aid future designers.
Control theory, Volume 1, covering linear, nonlinear, stochastic, optimal, adaptive and learning systems, sensitivity analysis, etc
Optimal control surface location for flexible aircraft determined by matrix minimum principle and calculus of variations
Integrated temperature and humidity control and water recovery subsystem for manned test in space station simulator
Inventory control of mercury condensing pressure during SNAP 8 startup
Deadband condenser inlet pressure control method for SNAP 8 startup
Control algorithm for optimization of nonlinear stochastic processes with discounted performance criteria
Systems design criteria for spacecraft attitude control during thrusting maneuvers
Reduced runway separation standards are among the means which have been proposed for increasing airport capacity. The probability of a blunder will dominate the calculation of safe separation standards. Then the determinant of safe system performance will be the system reaction time comprised of the air traffic controller's detection, decision and communication delays, and the response times of the pilot and aircraft in executing a collision avoidance manuever. Estimates of these times, based on existing data, show that the delays ascribable to the human portions of the man-machine system are comparatively unimportant. New developments in radar, computers, and data links will be required to provide any substantial improvement of the existing system, and the goal of 2500 ft of separation may not be achievable.
A study of the elastic effects of large area solar arrays on attitude control of a spacecraft was conducted. It is demonstrated for sufficiently low structural frequencies that excitation of certain modes can induce instability in the pitch axis. Stiffening the arrays can eliminate the instability. However, a severe weight penalty is associated with such modification. A more efficient means of minimizing the structural interaction effects is to change the shape of the array. For stable configurations, another problem may be encountered. This is the imposition of high rates on the spacecraft bus by oscillation of the solar arrays. Since low rates are required to obtain accurate science experiment results, it is imperative that the high rate problem be resolved. This also is possible by changing the solar array configuration.