Validation of the attitude control of KNATTE with flexible appendages

Abstract: The effect of flexible panels on a spacecraft during attitude movement may induce problems if not correctly accounted for in the control system for the spacecraft. The aim of this thesis is to find and evaluate, control algorithms that could be suitable for the Kinesthetic Node and Autonomous Table-Top Emulator (KNATTE) with two flexible mock-up solar panels during an attitude movement of 20 degrees. A simulation model of KNATTE was derived in a previous thesis where a Linear– quadratic–Gaussian (LQG) controller was also found, after a literature review the secondary controller was selected to be a Sliding mode control (SMC) and to accurately simulated the environment of KNATTE the continuous control signal would need to be converted to a pulse due to the thrusters on KNATTE either being on or off. The thesis found that the Pulse-width pulse-frequency (PWPF) modulation is necessary for both controllers to have the best performance as the Pulse-width modulation (PWM) is not able to generate a thrust output that gives a desired result. It is also found that the SMC will provide the shortest settling time for the attitude manoeuvre while also displacing the panels the least amount compared to that of the LQG controller.