A Study on the Impact of Traversability Measures on Rough Terrain Path Planning

Abstract: This thesis examines how the subspace of traversable paths is affected by extending the traditional definition of traversability, which solely considers the terrain topology, to also incorporate concern towards the vehicles configuration. Additionally, the effect of added consideration towards parameters such as roll, pitch, distance to target and ground clearance, are examined with respect to path planning and cabin comfort during operation. The study focuses primarily on rougher terrain. The results show that the subspace of traversable paths is indeed extended in some cases, but may also be reduced. The extension enabled the simulated vehicle to straddle an obstacle, which it would not otherwise cross. The traversable subspace may be reduced by defining too conservative feasibility limits on critical dynamic parameters for the feasibility check, such as slope. The results indicate that there exists a correlation between an increase in operator comfort and path length in several cases. This relationship is highly dependent on the terrain. Factors such as ground clearance were found to have little-to-no impact on the planned route while the angular position and velocity had an observable impact. The extended way to define traversability shows promise for future practical implementation but the results indicate the need for robust, detailed and validated modelling of the vehicle and environment.