Getting mobile autonomous robots to form a prescribed geometric arrangement

Abstract

Mobile autonomous robots present an interesting example within the subject of distributed control systems. There are several motor-driven wheeled robots that are autonomous in that their actions are subject only to sensor inputs and pre-loaded programs; there is no leader and no supervisor. The problem is to design the onboard controllers so that the robots perform a useful cooperative task. For example, suppose the robots all have antennas, forming an antenna array, and the collective task is to shape and point the radiated beam of the array. This requires the robots to form a certain geometric pattern. Previous work in this area has focussed mainly on the rendezvous problem, where the desired task is to meet at a common location (without navigational instruments). In this paper the task is to form a prescribed geometric arrangement, such as a regular polygon. The arrangement is defined by a rigid graph with link lengths. Nonlinear control laws are developed and the closed-loop equilibria are studied in detail. © 2008 Springer London.