Evaluation of Uneven Terrain Traversability for Wheeled Mobile Robots by Fractal Terrain Model

Planetary rover should be designed so that it can travel on uneven terrains robustly under several limitations such as size, weight, costs, etc. However, it is difficult to get precise or whole terrain information beforehand to check the performance of the designed rover. In this paper, we propose a simulation model of uneven terrains based on fractional Brownian motions (fBm’s) for evaluating traversability of mobile robots. Using fBm model, one can generate various terrain models by changing only two parameters. We modeled two different terrains by using fBm and checked statistical traversability of a robot with different wheel sizes and body configurations in computer simulation. To validate the effectiveness of the fBm model, we conducted real experiments with a wheeled mobile robot. Probabilities that the robot can travel a certain distance well agreed with the simulation results. The proposed method would be useful to find a guideline for designing planetary rovers and some new rover mechanisms that can travel on uneven terrains robustly.