Decentralized attitude coordinated control without velocity measurements for spacecraft formation

This paper addresses a decentralized quaternion-based controller for attitude tracking synchronization in spacecraft formation, without angular velocity measurements. Passivity approach is deployed to remove the requirements for absolute angular velocity measurements and relative angular velocity measurements between neighboring spacecrafts. The proposed control law guarantees that each spacecraft approaches its desired time-varying attitude and angular velocity while achieving attitude synchronization among spacecrafts during formation maneuvers. The only assumption on inter-spacecraft communication topology is being bidirectional. The stability of the resulting closed-loop systems is proved by virtue of LaSalle´s invariance principle. Simulation results demonstrate the effectiveness of the proposed attitude tracking synchronization controller for spacecraft formation in the absence of angular velocity measurements.