In the stream of research that aims to speed up practical planners, we propose a new approach to task planning based on Probabilistic Roadmap Methods (PRM). Our contribution is twofold. The rst issue concerns an extension of GraphPlan[1] specially designed to deal with \local planning" in large domains. Having a reasonably e cient \local planner", we show how we can build a \global task planner...

We present the first planner capable of reasoning with both the full semantics of PDDL2.1 (level 3) temporal planning and with numeric resources. Our planner, CRIKEY3, employs heuristic forward search, using the start-and-end semantics of PDDL2.1 to manage temporal actions. The planning phase is interleaved with a scheduling phase, using a Simple Temporal Network, in order to ensure that tempor...

Multiped locomotion in cluttered environments is addressed as the problem of planning acyclic sequences of contacts, that characterize the motion. In order to overcome the inherent combinatorial difficulty of the problem, we separate it in two subproblems: first, planning a guide trajectory for the root of the robot and then, generating relevant contacts along this trajectory. This paper propos...

Path planning systems using graph-search algorithms such as A* usually operate in uniform plan-view occupancy grids. However, the sensors used to construct these grids observe the environment in their own sample space based on sensor type and viewpoint. In this paper we present an image space technique for path planning in unknown unstructured outdoor environments. Our method differs from previ...

We describe a stochastic techuique for p l d n g colllion-frec path. of robots with many deof freedom (DOF's). The algorithm incrementally builds a graph connecting the local "a of a potential function defined in the robot's configuration space and concurrently searches this graph until a goal configurationis attained. A local minimum is connected to another one by executing a random motion tha...

ZUSAMMENFASSUNG. Expertensysteme sind wissensbasierte Kl-Systeme, die Expertenwissen und die darauf beruhenden Fähigkeiten maschinell verfügbar machen. Der Aufsatz gibt einen einführenden Überblick über Expertensysteme, die zur Unterstützung der ärztlichen Urteilsbildung entwickelt wurden. Es wird der Forschungsund Entwicklungsstand im Bereich der Inferenz-, Planungs-, Erklärungs-, Wissenserwer...

For planning to come of age, plans must be judged by a measure of quality, such as the total cost of actions. This report describes an optimal-cost planner which guarantees global optimality whenever the planning problem has a solution. We code the extraction of an optimal plan, from a planning graph with a fixed number k of levels, as a weighted constraint satisfaction problem (WCSP). The spec...

Graphplan (Blum & Furst 1995) has proved a popular and successful basis for a succession of extensions. An extension to handle temporal planning is a natural one to consider, because of the seductively time-like structure of the layers in the plan graph. TGP (Smith & Weld 1999) and TPSys (Garrido, Onaindı́a, & Barber 2001; Garrido, Fox, & Long 2002) are both examples of temporal planners that ha...

The current best conformant probabilistic planners encode the problem as a bounded length CSP or SAT problem. While these approaches can find optimal solutions for given plan lengths, they often do not scale for large problems or plan lengths. As has been shown in classical planning, heuristic search outperforms CSP/SAT techniques (especially when a plan length is not given a priori). The probl...