A New Approach to Temporal Planning with Rich Metric Temporal Properties

Abstract

Temporal logics have been used in autonomous planning to represent and reason about temporal planning problems. However, such techniques have typically been restricted to either (1) representing actions, events, and goals with temporal properties or (2) planning for temporally-extended goals under restrictive assumptions. We introduce Mixed Propositional Metric Temporal Logic (MPMTL) where formulae are built over mixed binary and continuous real variables. We introduce a planner, MTP, that solves MPMTL problems and includes a SAT-solver, model checker for a polynomial fragment of MPMTL, and a forward search algorithm. We extend PDDL 2.1 with MPMTL syntax to create MPDDL and an associated parser. The empirical study shows that MTP outperforms the state-of-the-art PDDL+ planner SMTPlan+ on several domains it performed best on and MTP performs and scales on problem size well for challenging domains with rich temporal properties we create.