Decentralized Multi-Robot Teams Using Wheeled Manipulation for Object Transportation
Object transportation is an especially suitable task for cooperative mobile robots where the carrying capacity of an individual robot is naturally limited. In this work, a unique wheeled robot is presented that, when used in homogeneous teams, is able to lift and carry objects which may be significantly larger than the robot itself. A key feature of the presented robot is that it is devoid of articulated manipulation mechanisms, but instead relies on its drive wheels for object interaction. After a brief introduction to the mechanics of this mobile robot, a behavior-based lifting and carrying strategy is developed that allows the robot to cooperatively raise an object from the ground, transition into a carrying role, and then transport the object across cluttered, unstructured terrain. The strategy is inherently decentralized, allowing an arbitrary number of robots to participate in the transportation task. Dynamic simulation results are then presented, showing the effectiveness of the strategy.