DCA: a distributed control architecture for robotics

Abstract

Many control applications are by nature distributed, not only over different processes but also over several processors. Managing such a system with respect to the startup of processes, internal communications and state changes quickly becomes a very complex task. The paper presents a distributed control architecture which supports a formal model of computation as described by Lyons and Arib (1989). The architecture is primarily intended for robot control but has a wide range of potential applications. We motivate the design and implementation of the architecture by discussing the desired properties of a robot system capable of doing real-time tasks like manipulation. This leads to functionality such as a process algebra controlling the life-cycle of the processes, grouping and distribution of processes and internal communication transparent to location. Our implementation does not in itself introduce any bottlenecks due to a tree structure with local control over processes which gives an efficient and scalable architecture. At the end, an example scenario in which a fairly advanced problem like opening a door using a mobile robot with a manipulator arm is demonstrated in the presented framework.