Terrain Recognition Based on the Wheel Contact Angle Measurement using Laser Scanners for Six-Wheel Mobile Robot

Abstract

This work presents a mobile robot for delivery services that use laser scanning sensors to recognize the local geometry of the terrain, using the contact angle parameter that gives information regarding the surface that the wheel touches the ground. Thus, the proposed method allows proper robot control to climb up and down safely in rigid terrains. We calculate the Jacobian matrix and its inverse to obtain the kinematic model of a wheeled robot that receives the contact angle measurement between wheel-ground and adjusts the velocity according to the terrain contact. A slip control is also implemented based on the slip ratio to guarantee the robot continues climbing. The simulation and experiment demonstrate the accuracy of the contact angle measurement between wheel-ground using laser sensors and the successful capability of the mobile robot to climb up and down.