Dynamics and distributed control of modular robotic systems

Modular robotic systems provide flexibility and versatility for applications to many different tasks. Such systems may be reconfigured into alternative forms in order to support different kinematic, workspace, and mobility needs. The design of modular distributed algorithms and architectures for control of these systems is particularly challenging since kinematic and dynamic performance must be maintained throughout a range of alternative physical reconfigurations. In this paper, we review progress an the development of the "Tetrobot" modular robotic system. that uses parallel, variable geometry truss-like mechanisms and can be reconfigured to create moving platforms. walking machines, manipulator arms, a pipe crawler and other devices. In recent work, dynamic distributed control of active rolling motions of tetrobot structures has been explored and demonstrated in simulation for complex structures. The underlying principles of distributed control for modular systems generalize beyond these specific mechanisms, and the resulting Tetrobot system has a range of interesting applications including space robotics. construction, mining, medical. undersea, and flexible manufacturing.