Clearing an orthogonal polygon to find the evaders

Abstract

In a multi-robot system, a number of autonomous robots would sense, communicate, and decide to move within a given domain to achieve a common goal. In the pursuit-evasion problem, a polygonal region is given and a robot called a pursuer tries to find some mobile targets called evaders. The goal of this problem is to design a motion strategy for the pursuer such that it can detect all the evaders. In this paper, we consider a new variant of the pursuit-evasion problem in which the robots (pursuers) each moves back and forth along an orthogonal line segment inside a simple orthogonal polygon P. We assume that P includes unpredictable, moving evaders that have bounded speed. We propose the first motion-planning algorithm for a group of robots, assuming that they move along the pre-located line segments with a constant speed to detect all the evaders with bounded speed. Also, we prove an upper bound for the length of the paths that all pursuers move in the proposed algorithm.