Characterization, optimization, and test of the NPSATI MEMS 3-axis sensor suite for use in small satellite attitude control

Abstract

The NPSAT1 project is a Naval Postgraduate School (NPS) educational small satellite combining student education in satellite systems and operations, institutional research, and sponsored experiments with the objective of testing technologies for applications in space flight. The micro-electro-mechanical system (MEMS) rate sensor is one of these experimental technologies. Packaging three of these MEMS sensors together makes a 3-axis rate sensor suite. The MEMS experiment was originally conceived of as a low-cost, low-mass augmentation to the magnetometer for use by the Attitude Control System (ACS). The experiment is to test the sensor suite's ability to measure NPSAT1 rates, comparing these rates to those determined by using a magnetometer and GPS. Operationally, the goal is to perform a space-flight demonstration of the MEMS sensor. This thesis includes two phases of research and development. First, the MEMS 3- axis rate sensor suite is fully tested and characterized. Experimental testing proves the sensor suite's effectiveness as a low-cost, low-mass augmentation to the magnetometer for satellite rate determination, as well as its ability to measure very low rates. Second, we adapt the original design and operations to maximize the accuracy and utility of the sensor suite. Finally, a complete flight-like subsystem is built and tested.