Planning & Scheduling
Approximate Policy Iteration with a Policy Language Bias
Fern, Alan, Yoon, Sungwook, Givan, Robert
We explore approximate policy iteration, replacing the usual costfunction learning step with a learning step in policy space. We give policy-language biases that enable solution of very large relational Markov decision processes (MDPs) that no previous technique can solve. In particular, we induce high-quality domain-specific planners for classical planning domains (both deterministic and stochastic variants) by solving such domains as extremely large MDPs.
Auction Mechanism Design for Multi-Robot Coordination
Bererton, Curt, Gordon, Geoffrey J., Thrun, Sebastian
The design of cooperative multi-robot systems is a highly active research area in robotics. Two lines of research in particular have generated interest: the solution of large, weakly coupled MDPs, and the design and implementation of market architectures. We propose a new algorithm which joins together these two lines of research. For a class of coupled MDPs, our algorithm automatically designs a market architecture which causes a decentralized multi-robot system to converge to a consistent policy. We can show that this policy is the same as the one which would be produced by a particular centralized planning algorithm. We demonstrate the new algorithm on three simulation examples: multi-robot towing, multi-robot path planning with a limited fuel resource, and coordinating behaviors in a game of paint ball.
ARA*: Anytime A* with Provable Bounds on Sub-Optimality
Likhachev, Maxim, Gordon, Geoffrey J., Thrun, Sebastian
In real world planning problems, time for deliberation is often limited. Anytime planners are well suited for these problems: they find a feasible solution quickly and then continually work on improving it until time runs out. In this paper we propose an anytime heuristic search, ARA*, which tunes its performance bound based on available search time. It starts by finding a suboptimal solution quickly using a loose bound, then tightens the bound progressively as time allows. Given enough time it finds a provably optimal solution. While improving its bound, ARA* reuses previous search efforts and, as a result, is significantly more efficient than other anytime search methods. In addition to our theoretical analysis, we demonstrate the practical utility of ARA* with experiments on a simulated robot kinematic arm and a dynamic path planning problem for an outdoor rover.
ARA*: Anytime A* with Provable Bounds on Sub-Optimality
Likhachev, Maxim, Gordon, Geoffrey J., Thrun, Sebastian
In real world planning problems, time for deliberation is often limited. Anytime planners are well suited for these problems: they find a feasible solution quickly and then continually work on improving it until time runs out. In this paper we propose an anytime heuristic search, ARA*, which tunes its performance bound based on available search time. It starts by finding a suboptimal solution quickly using a loose bound, then tightens the bound progressively as time allows. Given enough time it finds a provably optimal solution. While improving its bound, ARA* reuses previous search efforts and, as a result, is significantly more efficient than other anytime search methods. In addition to our theoretical analysis, we demonstrate the practical utility of ARA* with experiments on a simulated robot kinematic arm and a dynamic path planning problem for an outdoor rover.
Envelope-based Planning in Relational MDPs
Gardiol, Natalia H., Kaelbling, Leslie P.
A mobile robot acting in the world is faced with a large amount of sensory data and uncertainty in its action outcomes. Indeed, almost all interesting sequential decision-making domains involve large state spaces and large, stochastic action sets. We investigate a way to act intelligently as quickly as possible in domains where finding a complete policy would take a hopelessly long time.
Approximate Policy Iteration with a Policy Language Bias
Fern, Alan, Yoon, Sungwook, Givan, Robert
We explore approximate policy iteration, replacing the usual costfunction learning step with a learning step in policy space. We give policy-language biases that enable solution of very large relational Markov decision processes (MDPs) that no previous technique can solve. In particular, we induce high-quality domain-specific planners for classical planning domains (both deterministic and stochastic variants) by solving such domains as extremely large MDPs.
Auction Mechanism Design for Multi-Robot Coordination
Bererton, Curt, Gordon, Geoffrey J., Thrun, Sebastian
The design of cooperative multi-robot systems is a highly active research area in robotics. Two lines of research in particular have generated interest: the solution of large, weakly coupled MDPs, and the design and implementation of market architectures. We propose a new algorithm which joins together these two lines of research. For a class of coupled MDPs, our algorithm automatically designs a market architecture which causes a decentralized multi-robot system to converge to a consistent policy. We can show that this policy is the same as the one which would be produced by a particular centralized planning algorithm. We demonstrate the new algorithm on three simulation examples: multi-robot towing, multi-robot path planning with a limited fuel resource, and coordinating behaviors in a game of paint ball.
Approximate Policy Iteration with a Policy Language Bias
Fern, Alan, Yoon, Sungwook, Givan, Robert
We explore approximate policy iteration, replacing the usual costfunction learningstep with a learning step in policy space. We give policy-language biases that enable solution of very large relational Markov decision processes (MDPs) that no previous technique can solve. In particular, we induce high-quality domain-specific planners for classical planningdomains (both deterministic and stochastic variants) by solving such domains as extremely large MDPs.
Envelope-based Planning in Relational MDPs
Gardiol, Natalia H., Kaelbling, Leslie P.
A mobile robot acting in the world is faced with a large amount of sensory dataand uncertainty in its action outcomes. Indeed, almost all interesting sequentialdecision-making domains involve large state spaces and large, stochastic action sets. We investigate a way to act intelligently asquickly as possible in domains where finding a complete policy would take a hopelessly long time. This approach, Relational Envelopebased Planning(REBP) tackles large, noisy problems along two axes.
ARA*: Anytime A* with Provable Bounds on Sub-Optimality
Likhachev, Maxim, Gordon, Geoffrey J., Thrun, Sebastian
In real world planning problems, time for deliberation is often limited. Anytime planners are well suited for these problems: they find a feasible solutionquickly and then continually work on improving it until time runs out. In this paper we propose an anytime heuristic search, ARA*, which tunes its performance bound based on available search time. It starts by finding a suboptimal solution quickly using a loose bound, then tightens the bound progressively as time allows. Given enough time it finds a provably optimal solution. While improving its bound, ARA* reuses previous search efforts and, as a result, is significantly more efficient thanother anytime search methods. In addition to our theoretical analysis, we demonstrate the practical utility of ARA* with experiments on a simulated robot kinematic arm and a dynamic path planning problem foran outdoor rover.