Quadratic Programming for Multirobot and Task-Space Force Control

Abstract

We have extended the task-space multiobjective controllers that write as quadratic programs (QPs) to handle multirobot systems as a single centralized control. The idea is to assemble all the 'robots' models and their interaction task constraints into a single QP formulation. By multirobot, we mean that whatever entities a given robot will interact with (solid or articulated systems, actuated, partially or not at all, fixed-base or floating-base), we model them as clusters of robots and the controller computes the state of each cluster as an overall system and their interaction forces in a physically consistent way. By doing this, the tasks specification simplifies substantially. At the heart of the interactions between the systems are the contact forces; methodologies are provided to achieve reliable force tracking by our multirobot QP controller. The approach is assessed by a large panel of experiments on real complex robotic platforms (full-size humanoid, dexterous robotic hand, fixed-base anthropomorphic arm) performing whole-body manipulations, dexterous manipulations, and robot-robot comanipulations of rigid floating objects and articulated mechanisms, such as doors, drawers, boxes, or even smaller mechanisms like a spring-loaded click pen.