Simple Orbit and Attitude Control Using Vacuum Arc Thrusters for Picosatellites

摘要

The possibility of maintaining a group of picosatellites in a bounded formation using very low-power electric propulsion (less than 2 W) is presented. A model predictive controller is used to develop a simple control scheme that avoids the need for an online orbit determination system. The control law, verified using a high-fidelity propagator, is capable of maintaining pairs of picosatellites within a range less than 1500 km with an average △V of 2.5 m/s per month. To reduce power demands, a combined thruster-based orbit and attitude control system is used. Attitude accuracy is shown to be better than 0.5 deg. A suitable vacuum arc thruster propulsion system is presented, designed specifically for a one-unit CubeSat. The combined attitude-orbit control, the simplicity of the control law, and the proposed propulsion system provide an important advantage for implementation in a picosatellite with extremely limited resources.