Controllability analysis and attitude path planning of underactuated spacecraft systems

The controllability analysis and attitude path planning are addressed for an underactuated spacecraft using two flywheels as actuators. Considering the spacecraft and flywheels as a whole system, we describe the dynamics of the system on an angular momentum level set such that the system is controllable with arbitrary initial momentum and direction of the torque singular vector. Moreover, an optimal performance index is proposed with the influence of friction torques in flywheels considered. With this index being optimized, Gauss Pseudospectral Method (GPM) is used to design the attitude path of the system, which satisfies the spacecraft maneuver requirement. Finally, simulation results show the effectiveness of the attitude path planning method.