Segmented sliding mode control-based CubeSat rapid attitude manoeuvre in low magnetic environment

The rapid attitude manoeuvre is a control challenge for a CubeSat in low magnetic environments, which include lunar orbits, geosynchronous (GEO) orbits or other higher Earth orbits. Therefore, a rapid attitude manoeuvre control method based on the segmented sliding mode was proposed for CubeSat in a low magnetic environment. The segmented sliding mode control algorithm was applied to the CubeSat attitude manoeuvre control, where the segmented sliding mode surface was designed to guarantee fast convergence to the origin point of the whole attitude manoeuvre process, and the hyperbolic tangent function was used in the reaching law of the controller to alleviate reaction saturation of the wheels. In addition, innovative control strategies were proposed for the hybrid actuators of the reaction wheels and microthrusters, and a guide rail of the microthruster was innovatively designed to move the microthruster to offset the change in moment of inertia caused by propellant consumption. Finally, hardware-in-loop simulation results reveal that our method has a stronger anti-saturation ability and faster manoeuvre speed than the traditional control method, and the operational life cycle of the thrusters can be accordingly increased.