Amol Dattatraya Mali, Amitabha Mukerjee
In this paper, we examine the modularity assumption of behaviour-based models: that complex functionalities can be achieved by decomposition into simpler behaviours. In particular we look at the issue of conflicts among robot behaviour modules. The chief contribution of this work is a formal characterization of temporal cycles in behaviour systems and the development of an algorithm for detecting and avoiding such conflicts. We develop the mechanisms of stimulus specialization and response generalization for eliminating conflicts. The probable conflicts can be detected and eliminated before implementation. However the process of cycle elimination weakens the behaviour structure. We show how (a) removing conflicts results in less flexible and less useful behaviour modules and (b) the probability of conflict is greater for more powerful behaviour systems. We conclude that purely reactive systems are limited by cyclic behaviours in the complexity of tasks they can perform.