Exploiting Problem Symmetries in State-Based Planners

نویسندگان

  • Nir Pochter
  • Aviv Zohar
  • Jeffrey S. Rosenschein
چکیده

Previous research in Artificial Intelligence has identified the possibility of simplifying planning problems via the identification and exploitation of symmetries. We advance the state of the art in algorithms that exploit symmetry in planning problems by generalizing previous approaches, and applying symmetry reductions to state-based planners. We suggest several algorithms for symmetry exploitation in state-based search, but also provide a comprehensive view through which additional algorithms can be developed and fine-tuned. We evaluate our approach to symmetry exploitation on instances from previous planning competitions, and demonstrate that our algorithms significantly improve the solution time of instances with symmetries.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Strengthening Canonical Pattern Databases with Structural Symmetries

Symmetry-based state space pruning techniques have proved to greatly improve heuristic search based classical planners. Similarly, abstraction heuristics in general and pattern databases in particular are key ingredients of such planners. However, only little work has dealt with how the abstraction heuristics behave under symmetries. In this work, we investigate the symmetry properties of the p...

متن کامل

Exploiting State Constraints in Heuristic State-Space Planning

In the last years, some very promising domain independent heuristic state-space planners for STRIPS worlds, like ASP/HSP, HSPr and GRT, have been presented. These planners achieve remarkable performance in some domains, like the blocks world, the logistics and the gripper, but they are not effective in other domains, like the grid and the mystery. In this paper we propose the use of state const...

متن کامل

Exploiting generalisation symmetries in accuracy-based learning classifier systems: An initial study

Modern learning classifier systems typically exploit a niched genetic algorithm to facilitate rule discovery. When used for reinforcement learning, such rules represent generalisations over the state-action-reward space. Whilst encouraging maximal generality, the niching can potentially hinder the formation of generalisations in the state space which are symmetrical, or very similar, over diffe...

متن کامل

On Exploiting Structures of Classical Planning Problems: Generalizing Entanglements

Much progress has been made in the research and development of automated planning algorithms in recent years. Though incremental improvements in algorithm design are still desirable, complementary approaches such as problem reformulation are important in tackling the high computational complexity of planning. While machine learning and adaptive techniques have been usefully applied to automated...

متن کامل

Heuristic Evaluation Based on Lifted Relaxed Planning Graphs

In previous work we have shown that grounding, while used by most (if not all) modern state-of-the-art planners, is not necessary and is sometimes even undesirable. In this paper we extend this work and present a novel forward-chaining planner that does not require grounding and can solve problem instances that are too large for current planners to handle. We achieve this by exploiting equivale...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2011