Attitude control research with educational nanosatellites

Abstract

This paper introduces the three-axis attitude control of the ESAT platform. ESAT is a modular nanosatellite that implements the popular 10x10x10 cm CubeSat standard, designed for hands-on learning at different educational levels as well as professional training. ESAT features the full set of characteristic spacecraft subsystems (power, on-board data handling, attitude control, communications, and payload). The satellite can be disassembled to focus on each subsystem, one at a time, or used all together, and features a flexible ground segment. Courses using the ESAT platform are imparted in our university, as part of the last year of the master’s degree in Aerospace engineering, and in other institutions like the ESA Academy. They cover aspects ranging from subsystems design to testing and spacecraft operations. In addition, the platform is used in master’s thesis and research activities. Although the version that is currently being used in the courses allows only one-axis attitude control, the ESAT is in continuous development and two prototypes of the satellite have already been developed that allow three-axis control based on reaction wheels and/or magnetorquers, which is essential for the testing and verification of attitude determination and control algorithms. For this purpose, the ground support equipment has also been updated to be able to carry out the turns in three axes, with the development of new testbeds and a complete magnetic field simulator. The present work aims to show the new three-axis platform designs and its main functionalities