Using Physical Models to Plan Safe and Executable Motions for a Rover Moving on a Terrain

This paper deals with the trajectory planning problem of a mobile robot moving on a three dimensional terrain. The main contribution of this paper consists in presenting a method which introduces non-coarse problems such as: robot dynamics, physical interaction between the robot and the terrain, non collision and kinematic constraints , in the process of the trajectory generation. The basic idea of our method is to integrate physically based models of the robot and the terrain to a two levels trajectory planning process. Such a process is based upon a graph-search strategy mixed with an optimal control technique. We will describe how each level proceeds and how they interact to generate a sequence of sub-trajectories. Finally, we will show how both of the robot and the terrain are modelled, and how the contact between them is performed and used during the motion generation.