A practical approach to generalized hierarchical task specification for indirect force controlled robots

The main contribution of this paper is the general formulation of force and positioning tasks on joint and Cartesian level for indirect force controlled robots and combining them in a strict hierarchical way. As a secondary contribution, we provide a simple and intuitive programming paradigm, using the developed formulation. By building on the well-established indirect force control scheme, which is often already provided for commercial robots, we provide application programmers with a useful tool for specifying tasks, involving positioning and force components. Different physical interaction tasks have been implemented to show the potential of the proposed method and discuss the general advantages and drawbacks.