Because of the capability of extended accuracy, digital systems are indicated for guidance and control of spacecraft. Furthermore, by implementing these systems with integrated microelectronic components, substantial improvement in reliability can be expected. A study and experimental evaluation program was performed to apply such digital techniques to the spacecraft stabilization and control problem. Of major consideration were the selection of appropriate mathematical techniques for system analysis and the development of suitable fabrication methods for hardware implementation.
A discrete state model of a spacecraft reaction wheel and jet attitude control system was developed and computer simulations were performed. An electronic control unit for this system was designed, constructed with semiconductor integrated microelectronics, and tested on an air bearing simulator.
The mathematical model of the system is presented and the experimental performance is compared with the computer simulation of the system.