Task-oriented decentralized adaptive control of cooperative manipulators

In this paper, the decentralized control in task space of cooperative mobile arms with uncertain dynamics is considered. The cooperative task is specified by means of proper task-oriented variables depending on the end-effector configurations of all the arms in the team. Therefore, because of the lack of a centralized control unit, a two-layer architecture is proposed. At the first level, each arm controller runs a distributed observer in order to estimate the overall state of the system. At the second level, this estimate is used to compute the local control input in order to achieve the global cooperative task. Moreover, the dynamic parameters of the arms might not be perfectly known, thus the local control law has to be made adaptive in order to counteract this uncertainty. The approach was validated by simulation with 6-DOFs serial chain manipulators mounted on a mobile platform and performing a cooperative task.