This paper presents a multi-robot long-term planning approach under uncertainty on the duration of tasks. The proposed method- ology takes advantage of generalized stochastic Petri nets to model multi-robot teams. It allows for unified modeling of action selection and uncertainty on duration of action execution. Goals are specified through the use of transition rewards and rewards per time unit. Our approach exploits the semantics provided by Markov reward automata in order to synthesize policies that optimize the long-run average reward. We provide an empirical evaluation on a simulated multi-robot monitoring problem, showing that the synthesized pol- icy outperforms a carefully hand-crafted policy.


Long-Run Multi-Robot Planning With Uncertain Task Durations

When planning for multi-robot navigation tasks under uncertainty, the presence of multiple robots in the same part of the environment simultaneously can have an adverse effect on navigation performance. We refer to this effect as congestion. Existing solutions fail to model congestion at planning time, which leads to inefficient behaviour. In this presentation, I will detail how to probabilistically model congestion, presenting a structure called the probabilistic reservation table that summarises the plans of robots using continuous-time Markov chains. I will then show how this structure can be used for planning by outlining an approach that, for each robot, sequentially builds and solves a Markov decision process where the transition probabilities are obtained by querying the probabilistic reservation table.


Multi-Robot Planning Under Uncertainty with Congestion-Aware Models

This paper presents a multi-robot long-term planning ap- proach under uncertainty on the duration of tasks. The proposed method- ology takes advantage of a novel modeling formalism for robot teams: generalized stochastic Petri nets with rewards (GSPNR). A GSPNR al- lows for unified modeling of action selection and uncertainty on the du- ration of action execution. At the same time, it allows for goal specifi- cation through the use of transition rewards and rewards per time unit. Our proposed approach exploits the well-defined semantics provided by Markov reward automata in order to synthesize policies for GSPNRs. It builds on a state-of-the-art method to compute the long-run average reward, extending it in order to allow for the extraction of the optimal policy. We provide an empirical evaluation of the proposed approach on a simulated multi-robot monitoring problem, evaluating its performance and scalability. The results show that, the obtained policy outperforms a carefully hand-crafted policy.


Long-run multi-robot planning with uncertain task durations

Doctoral Mentoring

technical paper

AAMAS is the leading scientific conference for research in autonomous agents and multi-agent systems. The AAMAS conference series was initiated in 2002 as the merging of three respected scientific meetings: the International Conference on Multi-Agent Systems (ICMAS), the International Workshop on Agent Theories, Architectures, and Languages (ATAL), and the International Conference on Autonomous Agents (AA). The aim of the joint conference is to provide a single, high-profile, internationally-respected archival forum for scientific research in the theory and practice of autonomous agents and multi-agent systems.

Browse keynotes, discussions, panels and over 300 presentations.


AAMAS 2020

AAMAS is the leading scientific conference for research in autonomous agents and multi-agent systems. The AAMAS conference series was initiated in 2002 as the merging of three respected scientific meetings: the International Conference on Multi-Agent Systems (ICMAS), the International Workshop on Agent Theories, Architectures, and Languages (ATAL), and the International Conference on Autonomous Agents (AA). 

Bruno Lacerda

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2

Presentations

Long-Run Multi-Robot Planning With Uncertain Task Durations

Multi-Robot Planning Under Uncertainty with Congestion-Aware Models

Long-run multi-robot planning with uncertain task durations