Vehicle/arm coordination and multiple mobile manipulator decentralized cooperation

Mobile manipulation capabilities are key to many new applications of robotics in space, underwater construction, and service environments. This article discusses the ongoing effort at Stanford University for the development of multiple mobile manipulation systems and presents the basic models and methodologies for their analysis and control. This work builds on four methodologies we have previously developed for fixed-base manipulation: the operational space formulation for task-oriented robot motion and force control; the dextrous dynamic coordination of macro/mini structures for increased mechanical bandwidth of robot systems; the augmented object model for the manipulation of objects in a robot system with multiple arms; and the virtual linkage model for the characterization and control of internal forces in a multi-arm system. We present the extension of these methodologies to mobile manipulation systems and propose a new decentralized control structure for cooperative tasks. The article also discusses experimental results obtained with two holonomic mobile manipulation platforms we have designed and constructed at Stanford University