Extending assumption-based TMS for qualitative reasoning

We present an extension of the HEART system developed by Joubel and Raiman (1990). This extension makes it possible to perform qualitative reasoning. HEART includes an assumption-based truth maintenance system (ATMS) and a temporal constraint propagator (TCP). Our extension allows the manipulation of qualitative data. This extended system is linked with a qualitative simulator based on QSIM. In our qualitative simulator, qualitative parameters and tendencies (time derivatives of parameters) take their values in a quantity space based on intervals. Furthermore, time is represented explicitly, thus permitting the treatment of facts such as “the robot is at the door at time 10”. We present a method of performing assumption-based truth maintenance in a qualitative-based temporal logic. This is based on the results of a previous work that considered assumption truth maintenance systems from a logical perspective