TOWARDS MODULAR COOPERATION BETWEEN MULTIPLE NONHOLONOMIC MOBILE MANIPULATORS

摘要

In recent times, there has been considerable interest in creating and deploying modular cooperating collectives of robots. Interest in such cooperative systems typically arises when certain tasks are either too complex to be performed by a single robot or when there are distinct benefits that accrue by cooperation of many simple robotic modules. In this dissertation, we examine these aspects in the context of cooperative payload manipulation and transport by wheeled mobile module collectives with tightlycoupled dynamics arising from the physical interactions between various modules. Our basic module is a wheeled mobile manipulator (WMM) formed by mounting a multi-link manipulator on top of a disk wheeled mobile base. By merging mobility with manipulation, mobile manipulators derive significant novel capabilities for enhanced interactions with the world. However, a careful resolution of the redundancy and active control of the reconfigurability created by the surplus articulated degrees-of-freedom and actuation is key to unlocking this potential. Addition of nonholonomic constraints creates additional challenges when disk wheeled mobile base is used and needs to be carefully addressed.