Flexible spacecraft attitude maneuver by application of sliding mode control

A sliding mode control strategy for the three-axis attitude maneuver of a flexible spacecraft model is proposed. The proposed control approach is an extension of the pure rigid spacecraft control case. In the new approach, finite dimensional mathematical modeling is unnecessary in designing the feedback control law taking the flexibility effect into consideration. The angular velocity, attitude quaternion, and internal reaction torques are employed as primary control parameters in the resultant control law. For highly flexible structural model, ideal sliding surface producing pure rigid body motion may not be achievable. Hence, the new technique in this study provides extra degree of freedom to shape the closed-loop response of flexible spacecraft attitude maneuver.