Dynamic load distribution in cooperative manipulation tasks

Abstract

In cooperative manipulation tasks, load allocation is a crucial step in order to solve the intrinsic redundancy of the system. The desired wrench needs to be suitably distributed between the end-effectors to implement the desired motion of the manipulated object. In this framework, both the grasp kinematics and the individual capacities of each manipulator provide relevant constraints. On one hand, the end effector wrenches act on the object via the grasp geometry. On the other hand, the individual admissible payload further depends on the current configuration of the robots. In this paper we focus on a heterogeneous cooperative manipulation setting and we design a proper allocation strategy to distribute the desired object wrench, considering both constant and time-varying constraints for the load distribution. The relevance of our findings is illustrated by means of an experimental study involving two anthropomorphic robots manipulating a common object.