Laser-Based Rut Detection and Following System for Autonomous Ground Vehicles

An important off-road driving rule is to keep the vehicle wheels in existing ruts when possible. Rut following has the following benefits: (1) it prevents the ruts from serving as obstacles that can lead to undesirable vehicle vibrations and even vehicle instability at high speeds; (2) it improves vehicle safety on turns by utilizing the extra lateral force provided by the ruts to reduce lateral slippage and guide the vehicle through its path; (3) it improves the vehicle energy efficiency by reducing the energy wasted on compacting the ground; and (4) it increases vehicle traction when traversing soft terrains such as mud, sand, and snow. This paper first presents a set of field experiments that illustrate the improved energy efficiency and traction obtained by rut following. Then, a laser-based rut detection and following system is proposed so that autonomous ground vehicles can benefit from the application of this off-road driving rule. The proposed system utilizes a path planning algorithm to aid in the rut detection process and an extended Kalman filter to recursively estimate the parameters of a local model of the rut being followed. Experimental evaluation on a Pioneer 3-AT robot shows that the proposed system is capable of detecting and following ruts in a variety of scenarios. (C) 2010 Wiley Periodicals, Inc.