Position and Attitude Control of a Free-Floating Planar Satellite Controlled by Thrusters

This study deals with the in-plane motion of a free-floating satellite equipped with thrusters whose force directions are fixed to the satellite. The system's governing equations form nonintegrable second-order “nonholonomic” constraints due to the fixed force directions to the satellite. This paper treats a satellite with three thrusters, and at first assumes that the magnitudes of the thrusters can continuously be changed from zero to a specified positive value. Under the assumption, it is shown that the nonholonomic governing equations can be transformed into holonomic ones by a feedback of the rotational angular velocity. Then, this paper shows the procedures to control the satellite's position and attitude precisely. Finally, we restrict the magnitude of the thrusters to be constant, and discuss the control techniques for such systems.