A design methodology for distributed control systems to optimize performance in the presence of time delays

When a control system is implemented in a distributed fashion, with multiple processors communicating over a network, both the communication delays associated with the network and the computation delays associated with the processing time can degrade the system's performance. In this case, the performance of the system may depend not only on the performance of the individual components but also on their interaction and cooperation. The approach taken in this paper assumes that the control has been designed without taking into account the network architecture. A theoretical framework is presented which allows the effect of time delays on the mechanical performance of the system to be precisely modelled, and these models are used to determine the optimal network architecture for the given control system. A design example of a two-axis contouring system is presented.