A door opening method by modular re-configurable robot with joints working on passive and active modes

In this paper, we study the problem of door-opening by using a modular re-configurable robot (MRR) mounted on a tracked mobile platform. The main concern of opening a door is how to prevent the internal forces that occur because of the positioning error or the imprecise modeling of the environment, i.e., the door parameters. Most previous research is based on compliant control, which makes the control system rather complicated. In addition, such approaches need expensive force/torque sensor to be implemented. With respect to the multiple working modes of the MRR modules, the complication has been avoided by switching the joints that has axis of rotation parallel to the door hinge to work in passive mode. As a result of this approach, the internal forces between the door and the mobile manipulator will vanish. Simulation results demonstrate the validity and efficiency of the proposed door opening strategy.