Cooperating grasping of a large object by multiple mobile robots

The authors aim at grasping and handling a large object by cooperating multiple mobile robots with various sizes, moving cost, and load capacity. In this paper the authors focus on the problems of deciding an appropriate grasping arrangement before handling operations. The authors propose this method to avoid bad situations, such as making an object fall down, or some robots overloaded in grasping and handling. The algorithm proposed includes two optimization problems; one is the “decision of initial robot arrangement,” the other is the “decision of final robot arrangement.” The difference between these optimizations is that the mass center of the object is recognized or not. The penalty index is defined to minimize the energy the system consumes and to maximize an index of stability. The authors have confirmed that the robots moved to the optimal arrangements in computer simulations and experiments