Sensor-based Path Planning: The Two-Identical-Link Hierarchical Generalized Voronoi Graph

Abstract

We present a new roadmap based on a generalized Voronoi graph (GVG) for two-identical-link (L-2) robots to explore an unknown planar environment. It is called the L-2 hierarchical generalized Voronoi graph (L-2-HGVG). The L-2 robot is formed by two equal length rods and a revolute joint between them. The configuration of the robot possesses four degree-of-freedom, two for position and two for orientation, and hence the roadmap is one-dimensional in an unknown configuration space R-2 x T-2. L-2-HGVG is defined in terms of workspace distance measurements using only sensor information without prior knowledge of the environment, with the robot having the maximum distance from obstacles, and is therefore optimum in a point of view for exploration and obstacle avoidance.