Publications

In this paper we address an important issue in the area of qualitative reasoning, that is, how to create qualitative models of mechanical devices that incorporate the effects of the detailed geometric structure of its components. The model we propose allows envisioning and prediction of behaviour without having to deal directly with the complexity of the detailed geometry of the parts. We claim that configuration spaces are an appropriate symbolic representation for reasoning about the kinematic behaviour of mechanical devices. We show that the kinematic behaviour of a mechanism can be precisely determined by first finding the relative motions of pairs of objects and then composing these motions. For a subclass of mechanisms, (fixed axis mechanisms), we show that a simplified version of the composition operation can be used to obtain the overall behaviour, and we outline a constraint propagation, label inferencing algorithm to produce a region diagram. This diagram constitutes a total qualitative envisionment of the mechanism’s behaviour. Finally, given a sequence of input motions and a region diagram, we indicate how to predict the behaviour of the mechanism.