Abstract: In order to analyze mobility performance and accomplish the simulation experiment of rocker-bogie exploration rover in the low gravity environment, domain of center of mass should be calculated. Two description methods of design parameters are presented on the basis of simplification of rocker-bogie suspension. Exploration rover is simplified as a particle system, and position vectors of all particles are established by coordinate transformation. Position vector in any time and domain radius of mass center of exploration rover are derived. Finally the developed rocker-bogie exploration rover is taken as an example, the design mass center and the mass center with any movement position are calculated, and the maximal domain radius of mass center is determined through optimization. Calculation results show that domain of mass center of rocker-bogie exploration rover is plane. The offset distance of body influences on mass center with any movement position, but does not effect on the domain of mass center. The method of calculating mass center can be applied for other passive articulated exploration rover.

Key words: Calculation, Domain of center of mass, Rocker-bogie exploration rover