Robot Navigation in Multi-terrain Outdoor Environments

This paper presents a methodology for motion planning in outdoor environments that takes into account specific characteristics of the terrain. Instead of decomposing the robot configuration space into “free” and “occupied”, we consider the existence of several regions with different navigation costs. Costs are determined experimentally by navigating the robot through the regions and measuring the influence of the terrain on its motion. In this paper we measure the robot vertical acceleration, which reflects the terrain roughness. A path planning algorithm is used to determine a sequence of triangles that minimize the navigation cost. Robot control is accomplished by a piecewise continuous vector field that drives the robot through those regions. This vector field allows the robot velocity to change according to the characteristics of the terrain. Experimental results with a differential driven, all terrain mobile robot illustrate the proposed approach.