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Project3: Evaluation of planning algorithms in the Rescue domain



General:
Path planning is a basic functionality for every Rescue agent. In the discretized setting of the RobocupRescue simulation, efficient AI search techniques can be used to find paths from an agent's current position to  a goal. However, the problem is complicated by the partial observability in the Rescue domain: while the road net of a city can be assumed to be fully known to each agent, the state of the roads (blockades) is not. On the other hand, the continuousness of the problems solved can be exploited: knowledge gained from past cycles of planning and plan execution (moving) can be reused.



Part I - Evaluation of heuristic search techniques


Function:
There are several heuristic search techniques that can be used in realistic settings where planning is continously interleaved with execution. Implement a general heuristic search engine in which some (or all) of the following methods can be plugged in: A*, Weighted A* (WA*), RTA*, LRTA* and variants of these algorithms. For partial observability planning you can consider techniques like Real-time Dynamic Programming (RTDP), AO*, LAO* and HDP.
Evaluate these search methods in the RoboCupRescue domain. You should compare the algorithms helpfulness both in offline pre-processing of a map (during the first cycles of the simulation) and online (while acting in the simulation).

Approach:
Heuristic search. Dynamic programming

Literature:
J. Pearl. Heuristics: Intelligent Search Strategies for Computer Problem Solving. Addison-Wesley, 1984.

S. Koenig. Agent-Centered Search. Artificial Intelligence Magazine, 22, (4), 109-131, 2001.

S. Koenig, D. Furcy and Colin Bauer. Heuristic Search-Based Replanning. In Proceedings of the International Conference on Artificial Intelligence Planning and Scheduling, 2002.

Andrew G. Barto, Steven J. Bradtke, Satinder P. Singh: Learning to Act using Real-Time Dynamic Programming, Artificial Intelligence 72: 81–138. 1995 

Blai Bonet and Hector Geffner.  Faster Heuristic Search Algorithms for Planning with Uncertainty and Full Feedback.  Proceedings of IJCAI-03.




Implementation:
The search engine can be implemented following the general GRAPH-SEARCH procedure of Russel/Norvig: AI - a Modern Approach, 2n ed., 2003.


Deliverables: