Comparative Analysis of Discrete-time Dual-Loop and Servo System Control Systems for CubeSats: An Optimized Design Approach

Cubesats, standardized nanosatellites, face significant challenges in attitude control due to limited energy resources. To address this issue, this study compares two discrete-time control system architectures suitable for this application: a servo system with integrator and a dual-loop controller employing a PI controller for speed and a proportional position controller. The controllers were designed to minimize an objective function directly correlated to the satellite’s energy consumption. Experimental results obtained from a prototype with a single-axis setup were compared with simulations, demonstrating that the dual-loop controller achieved a lower objective function than the servo system in the experiment. Also, the dual-loop controller was less sensitive to velocity measurement noise and dead zone effects. The findings of this study are valuable for considering the best attitude control architecture for CubeSats with restricted energy resources.