Topological Map Building with Multiple Agents Having Abilities of Dropping Indexed Markers

Abstract

This article introduces multi-agent strategy enabling multiple agents to explore an unknown environment with many obstacles, while generating a topological map in a cooperative way. Once a topological map is built, it can be used for various purposes, such as path planning or intruder capture. Multiple agents generate a Voronoi graph as a topological map of the environment, while dropping indexed markers at Voronoi vertices. Each agent has range sensors to detect nearby obstacles, thus can move along a Voronoi edge. Also, each agent stores the boundary for the explored region thus far, and unite its boundary with the boundary of another agent if some conditions are met. In this way, multiple agents can explore the entire workspace in a time efficient manner. The proposed exploration strategy doesn't require localization of an agent or a marker in global coordinate systems. To the best of our knowledge, this article is unique in addressing a multi-agent exploration and map building strategy, such that each agent drops indexed markers for generating a topological map of the environment. The effectiveness of the proposed exploration and mapping strategy is demonstrated utilizing MATLAB simulations.