Development of a Hardware-in-the-Loop Simulator for Control Moment Gyroscope-Based Attitude Control Systems.

摘要

In this thesis, an open-architecture control moment gyroscope (CMG) system is developed for hardware-in-the-loop (HIL) simulation of spacecraft attitude control. This effort included construction of four single-gimbal CMGs, implementation of an attitude dynamics model, a quaternion error feedback control system, and a pseudoinverse CMG steering law on a real-time controller. The modular design of the embedded flight computer software allows for various parameters (such as the spacecraft inertia tensor, CMG rate limits, and control system gains) to be rapidly iterated and deployed for testing on physical hardware. Real-time communication with the CMG hardware is achieved via a Controller Area Network (CAN) bus; CMG commanding and telemetry sampling (including position, velocity, and current) can be performed at different sampling frequencies. The impact of sampling frequency on control law determinism and the CMG gimbal rest position (referred to as gimbal drift) is demonstrated. The HIL simulation testbed developed in this thesis allows future researchers to evaluate novel attitude control and CMG steering algorithms as well as optimal attitude guidance in a real-time, laboratory environment.