Ian Miguel and Qiang Shen
This paper presents an extension to qualitative simulation that enables a QR system to support variables that exhibit delayed reactions to their constraining functions. Through a process of synchronised tracking, information stored in the previous levels of the behaviour tree can be retrieved and used to constrain multiple delayed variables. It is demonstrated that the extended simulation mechanism is powerful enough to capture the time-delay behaviour observed in actual physical systems. Experimental testing is described and results are provided.