Implementation of the MEMS-based dual-axis sun sensor for nano satellites

This paper describes the complete design, characterization, and satellite integration of a miniaturized two axis sun sensor which will be used in the attitude control system of Project STUDSAT-2 (STUDent SATellite-2). The sun sensor based on Micro-Electro-Mechanical systems (MEMS) technology has a sun field-of-view greater than ±62°, with angle accuracy better than 0.5°. The characteristics of the micro sun sensor make it very effective in terms of its operation on a nano satellite. The complete design details along with the simulation and testing results of the sensor processing electronics have been included. The general requirements in designing the circuit were to minimize the power consumption and mass of the circuit. The components were chosen based on these criteria. The electronics involves current to voltage conversions along with unique multiplexing methods and normalization technique for any unwanted errors. The working of the on-board sun vector algorithm with its Matlab analysis results is mentioned.