giorgio~dimi, uniud, it

clancy©cs, ut exas. edu We present a new method for specifying temporal constraints on trajectories of dynamical systems and enforcing them during qualitative simulation. Such constraints are otherwise inexpressible using stan-dard qualitative reasoning techniques. Trajectory con-straints can be used to restrict the simulation to a re-gion of the state space and to inject discontinuities. This capability can be used to focus the simulation for larger, more complex simulations, simulate non-autonomous and piecewise-continuous systems, rea-son about boundary condition problems and incorpo-rate observations into the simulation. The method has been implemented in TeQSIM, a qualitative simulator