Reactive Cooperative Manipulation based on Set Primitives and Circular Fields

Abstract

This paper addresses the problem of real-time planning in constrained dual-arm manipulation scenarios. Our proposed coupling leverages manipulability information of the cooperative bimanual task-space to a vector-field based planner by means of a repulsive circulatory field, while geometric primitives in Spin(3)⋉ℝ3 are explored for flexible task relaxation. Furthermore, the circular field informs the cooperative framework about the safety boundaries which are in turn used to further relax motion constraints within a collision-free ball in Cartesian space. This builds a funnel along the trajectory which can be directly tracked through the proposed switching of task-primitive-priorities. The switching strategy follows an approach that ensures robustness to chattering and continuity in the joint-space. Experiments verify that our framework can run within the inner control loop of Franka Emika Panda robots.