7. Continuous Constrained Attitude Regulation on SO(3)

In this chapter, both the centralized and distributed attitude regulation of multiple flexible spacecraft are studied on SO(3) with attitude constraints in the absence of the measurements of the angular velocities and modal coordinates. For centralized regulation, each spacecraft knows the desired attitude. A repulsive potential function is constructed to handle attitude constraints. Then a continuous controller is designed without the measurements of angular velocities. With the assumption that only some spacecraft know the desired attitude, a finite-time observer is introduced to estimate the leader’s information under fixed or switching communication graphs. A continuous control law is proposed for the distributed attitude regulation with the estimate of the leader as the reference signal.