Heterarchical control of highly distributed manufacturing systems

The use of heterarchical architectures to control manufacturing systems is becoming an increasingly attractive alternative to conventional hierarchical architectures as the density and level of distribution of computing resources in manufacturing systems grows. In this paper, design principles for heterarchical systems are reviewed that have evolved to promote reduced complexity, increased extensibility, self-configurability, and adaptation in real time. Challenges that arise in adhering to these principles such as cooperation between autonomous entities and potential for chaotic behaviour are discussed. Finally, heterarchical control is described for arrival time of parts at a machine where using local feedback control, system stability and convergence to meritorious states can be guaranteed, leading to confidence in system performance.