Skip to main content
SpringerLink
Log in

Improving concurrency in temporal plans

  • Published:
Artificial Intelligence Review Aims and scope Submit manuscript

Abstract

There is an increasing interest in solving temporal planning problems. Identification and propagation of mutual exclusion relations between actions can significantly enhance the efficiency of a planner. Current definitions of mutually exclusive actions severely restrict their concurrency. In this paper, we report on thirteen groups of permanently mutually exclusive PDDL 2.1, Level 3 actions. We report on sixteen types of potentially-conflicting interactions between two actions where concurrency may be maximized by adjusting starting time of one of the two actions. We discuss several examples where actions can overlap despite conflicting preconditions and/or effects. The processes executing these actions are mostly independent. We report on a new domain-rewriting technique called “baiting” in order to improve the concurrency in temporal plans. Baiting actions lure a temporal planner into improving concurrency. The technique involves splitting user-identified operators. We report on three types of baiting (standard, double and nested) and show their suitability for various types of action interactions. Baiting requires minimal modification to the planning code. Baiting does not increase the branching in search trees. Baiting does not affect the soundness and completeness of a temporal planner. Our empirical evaluation shows that the makespans of plans generated by efficient planner Sapa with baited domain are significantly lower than makespans of plans generated without baiting.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  • Bacchus F, Ady M (2001) Planning with resources and concurrency: a forward chaining approach. In: Proceedings of international joint conference on artificial intelligence (IJCAI), pp 417–424

  • Blum A, Furst M (1995) Fast planning via planning graph analysis. In: Proceedings of the international joint conference on artificial intelligence (IJCAI), pp 1636–1642

  • Dimopoulos Y, Gerevini A (2002) Temporal planning by mixed integer programming. In: Proceedings of AIPS workshop on planning in temporal domains, Toulouse, France, pp 2–8

  • Do M, Kambhampati S (2001) Sapa: a domain-independent heuristic metric temporal planner. In: Proceedings of European conference on planning (ECP), pp 109-120

  • Edelkamp S (2003) Taming numbers and durations in the model checking integrated planning system. J Artif Intel Res 20

  • Garrido A, Fox M, Long D (2002) A temporal planning system for durative actions of PDDL 2.1. In: Proceedings of the European conference on artificial intelligence (ECAI)

  • Gerevini A, Serina I (2002) LPG: a planner based on local search for planning graphs with action costs. In: Proceedings of international conference on artificial intelligence planning systems (AIPS), pp 13–22

  • Gerevini A, Serinav I, Saetti A, Spinoni S (2003) Local search techniques for temporal planning in LPG. In: Proceedings of the international conference on automated planning and scheduling (ICAPS)

  • Haslum P, Geffner H (2001) Heuristic planning with time and resources, Proceedings of European Conference on Planning (ECP) pp. 121–132

  • Kautz H, Selman B (1996) Pushing the envelope: planning, propositional logic and stochastic search. In: Proceedings of national conference on artificial intelligence (AAAI), Portland, OR, pp 1194–1201

  • Long D, Fox M (2001) Encoding temporal planning domains and validating temporal plans. Technical report, University of Durham, UK

  • Penberthy S, Weld D (1994) Temporal planning with continuous change. In: Proceedings of national conference on artificial intelligence (AAAI), pp 1010–1015

  • Sanchez J, Tang M, Mali A (2004) P-MEP: parallel more expressive planner. In: Proceedings of the 4th international planning competition, Whistler, Canada, June 2004

  • Smith D, Weld D (1999) Temporal planning with mutual exclusion reasoning. In: Proceedings of international joint conference on artificial intelligence (IJCAI), pp 326–333

Download references

Author information

Authors and Affiliations

  1. Department of Electrical Engineering & Computer Science, University of Wisconsin, Milwaukee, WI, 53211, USA

    Amol Dattatraya Mali

  2. MeVis Medical Solutions Inc., N27 W24075 Paul Ct., Suite 100, Pewaukee, WI, 53072, USA

    Michael Osowski

Authors
  1. Amol Dattatraya Mali
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Michael Osowski
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Amol Dattatraya Mali.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Mali, A.D., Osowski, M. Improving concurrency in temporal plans. Artif Intell Rev 35, 191–209 (2011). https://doi.org/10.1007/s10462-010-9190-x

Download citation

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10462-010-9190-x

Keywords

Search

Navigation