Global finite-time distributed attitude synchronization and tracking control of multiple rigid bodies without velocity measurements

This paper considers the global finite-time attitude synchronization and coordinated tracking problems of multiple rigid bodies without angular velocity measurements. First, for the attitude synchronization problem, by combining the hybrid technique and homogeneous theory, a new velocity-free attitude synchronization algorithm is constructed to prevent the unwinding problem and achieve finite-time convergence. In the second place, for the leader-following tracking problem, we firstly propose a nonlinear distributed hybrid observer for each follower such that the leader's information can be estimated accurately. Then, based on the outputs of the distributed observer, we propose a velocity-free distributed attitude tracking algorithm such that the global finite-time attitude tracking objective is achieved. Finally, simulation results are provided to demonstrate the effectiveness of the proposed algorithms.