Space Environment Modelling and Torque-Optimal Guidance for CubeSat Applications

CubeSats and nano-satellites provide flexible low-cost platforms for the academic and scientific communities to conduct cutting-edge research in the harsh environment of space. The mission life of nano-satellites is often limited by the attitude actuators, and it is therefore beneficial to reduce torque and angular momentum usage during reorientation maneuvers. In this capacity, a computationally lightweight torque-optimal guidance algorithm was formulated, solved using pseudospectral methods, and validated in a MATLAB-Simulink environment. A low-computation atmospheric density model, developed in support of this research, was extensively validated via performance assessment of passive CubeSat aerostabilization. Results indicate that this torque-optimal guidance algorithm demonstrates substantial improvements in performance and pointing accuracy over an Eigenaxis controller for similar maneuvers, with low to moderate computational overhead. In doing so, it presents a significant advancement towards the development of intelligent GN&C systems for small satellites.