“…A huge amount of literature on reachability have been published mainly in the field of abstract computational models see for example [10]. Examples of classical fields where the reachability problem is considered are graphs theory, [14,93,95,111], Petri nets, [80,81,85,110], motion planning, [54,76,77], geographical navigation, [2,3,32,92] and robotics, [69,77,109,112]. A feature common to most of the referred works deal with systems the behavior of which can be basically captured by identifying a set of well-defined discrete states.…”