Austin Bodin

Solar sails could remove the need for spacecraft to carry fuel, greatly expanding the range of possible missions. However, there is a current lack of scalable attitude control methods suitable for next generation solar sails. The Cable-Actuated Bio-inspired Lightweight Elastic Solar Sail (CABLESSail) is proposed to utilize cable-actuated sail booms for attitude control. However, previous research on the CABLESSail showed that feedback control on the boom deflections is critical to the overall attitude control. A well-behaved state estimation of the dynamic system is necessary for effective feedback control. This thesis presents an estimation method utilizing a Kalman filter along with a rate gyroscope and a rotary motor encoder. Estimation hardware is designed to interface with an existing CABLES-Sail prototype. Experiments utilize a Vicon motion capture system for ground truth data and show a promising root-mean-square estimation error of 1.0 mm for boom tip deflections up to 25 mm. Feedback control tests show reduced settling times for large amplitude oscillations compared to open-loop tests, demonstrating the viability of real-time estimation with this method. This work presents a light- weight, scalable process for obtaining a boom tip deflection estimate and will help guide future development of the CABLESSail project.