Decentralized control of multiple mobile manipulators based on virtual 3-D caster motion for handling an object in cooperation with a human

In this paper, we propose a decentralized control algorithm of multiple mobile manipulators for handling a single object in cooperation with a human. In this algorithm, a grasping point of each mobile manipulator is controlled as if it has a caster-like dynamics referred to as virtual 3-D caster, and each mobile manipulator could handle the object based on an intentional force/moment applied by a human. In addition, the coordination among multiple mobile manipulators was realized without using the geometric relations among robots. The proposed control algorithm is experimentally applied to two mobile manipulators referred to as DR HelperII and experimental results illustrate the validity of the proposed control algorithm.