A planning system for blocks-world domain

We present a planning system for the blocks-world domain. An important component of the system is a whole priority list, which guides the system in selecting suitable sub-goals in solving a given problem. This system is entirely different from existing systems, which are primarily based on either backtracking or on invariant intermediate states or random selection of subgoals. This system selects sub-goals in a systematic fashion. It generates a plan in polynomial time if there is no deadlock. The system has been implemented using Common Lisp. A graphical user interface is incorporated for the convenient specification of user inputs