Broadcast based fitness sharing GA for conflict resolution among autonomous robots

Abstract

This paper proposes a distributed GA for autonomous agents to learn in order to achieve co-operative action. Our objective is to develop a learning system that would make real-world heterogeneous agents feasible with the minimum amount of communication hardware. With such real-world agents, there are two constraints that make it difficult to estimate the global payoff: one, is that the communication bandwidth between the agents is limited to a small band-width. This prohibits the gathering of fitness values from all the agents. Second, is that local fitness values are always evaluated a long time after a conflict between agents has taken place. This means that some agents may be far away by then and will no longer be able to exchange local payoffs in order to calculate the estimated global payoff. To overcome these difficulties, we have developed a polarity based broadcast fitness sharing method for physically distributed populations. Instead of waiting for an exact local payoff, an estimated local payoff is exchanged whenever a conflict takes place. We found that a specific filter function gives a good estimate of global fitness values in conflict resolution tasks. Our results from simulations of a bump-avoidance task for multiple mobile robots show that it elicits a notable performance improvement.