The modelling and estimation of driving forces for unmanned ground vehicles in outdoor terrain

Ground vehicles traversing rough unknown terrain has many applications in a range of industries including agriculture, defence, mining, space exploration and construction. The interaction dynamics between the vehicle and the terrain play a crucial role in determining the mobility characteristics of the vehicle. The two critical parameters that influence the interaction dynamics are the wheel/track slip and the unknown soil parameters. An algorithm for identifying unknown soil parameters based on a dynamic model and sensor feedback is presented. A method for estimating vehicle slip parameters based on an optical flow algorithm and a sliding mode observer is also presented. The last section addresses the traversability prediction for tracked vehicles traversing in circular trajectories. The algorithms are developed for both tracked and wheeled vehicles. The algorithms are tested and evaluated using two specially designed test rigs, and the test results are presented in the paper.