Control of contact conditions for manipulation with multiple robotic systems

An object much larger than a robot end-effector can not be rigidly grasped. Instead, it is necessary to support the object with multiple effectors. The effectors need not be grippers-they may be surfaces on the arm(s). Multiple arm manipulation without rigid grasps is investigated. The interaction between a robot and the object is characterized by unilateral constraints. The closed chain topology, redundancy in actuation, and the nonlinear coupled equations of motion make the problem formidable. The approach used is to utilize a minimal set of inputs to control the trajectory. The surplus inputs are used to control the contact conditions (rolling, sliding, etc.)