Distributed multi-robot coalitions through ASyMTRe-D

This paper presents a distributed reasoning system, called ASyMTRe-D, which enables a team of robots to form coalitions to accomplish a multi-robot task through tightly-coupled sensor sharing. The theoretical foundation of the negotiation protocol is ASyMTRe, an approach we developed previously to synthesize task solutions according to the task requirements and the team composition. The goal of the ASyMTRe approach is to increase the task solution capabilities of heterogeneous multi-robot teams by changing the fundamental abstraction from the typical "task" abstraction to a "schema" abstraction and automatically reconfigure the schemas to address the task at hand. The decision-making in this prior work was fully centralized; the current paper presents a distributed version of this approach based on the contract net protocol, which can achieve higher levels of robustness than the centralized version. The purpose here is not to improve the original protocol, but to apply it to our problem so that the autonomous task solution capabilities of robots can be achieved in a distributed manner. Simulation results are provided to validate the protocol with performance analysis. Finally, we compare ASyMTRe-D with the centralized ASyMTRe. Our future objective is to enable the human designer to specify the desired balance between solution quality and robustness, enabling the reasoning approach to invoke the appropriate level of information-sharing among robots to reach the specified solution characteristics.