A Low-Cost Attitude Determination and Control System for the UYS-1 nanosatellite

This paper considers the development of a Low-Cost Attitude Determination and Control Subsystem (LCADCS) for the first Ukrainian University Nanosatellite, UYS-1. For the attitude determination part, an attitude determination framework is implemented to combine all available data at each time sample using a modified Unscented Kalman Filter, based on the Unscented Quaternion Estimator (USQUE). For the attitude control part, the subsystem should rely only on magnetic actuation with magnetorquers operating in a relay mode. A proposed control strategy is presented. The choice of hardware and algorithms is addressed observing the LCADCS requirements, theoretical and practical considerations, ease of implementation, and time and cost budgets inherent to small-satellite projects. The validity and performance of the general proposed systems are evaluated using computer simulations.