Distributed attitude synchronization for multiple rigid bodies without velocity measurement

Assuming the desired time-varying reference trajectory is available to all the rigid bodies, we consider distributed attitude synchronization for multiple rigid bodies only with attitude measurement. Based on two lead filters which remove the requirement of angular velocity, we propose control law composed of two parts to reduce tracking error and to achieve attitude synchronization, respectively. First, we show the closed loop system is globally bounded. Second, we show angular velocity synchronization by Barbalat's lemma. Third, we give the sufficient condition, which depends on the controller gain and weighted adjacency matrix of communication graph among rigid bodies, to guarantee that all rigid bodies asymptotically synchronize to desired reference attitude. Simulation results show the effectiveness of the proposed control law.