Preliminary Design of the Attitude Control System of a Microsatellite for Earth Observation

In this paper a low-weight, low-power magnetic attitude control system, consisting of three magnetic torquers, two magnetometers and a horizon sensor, is proposed for a microsatellite carrying a remote sensing payload on a Sun-synchronous orbit. Linear control laws are derived by making use of an attitude analytical model. The performance of the attitude control system is evaluated by using a numerical code which models the system orbital and attitude dynamics, and the sensor and attitude measurement errors. Final results show that the proposed preliminary design of the attitude control system allows the attitude angles to be kept within values adequate to the considered application.