Abstract: A transformable mobile robot with the characteristics of the combination of spherical robot and wheeled robot is designed. The mobile robot can adapt to a variety of complex terrain environment, and its geometry change achieves the exchange between the spherical robot and the wheel robot. The spherical-wheel mobile robot is composed of the deformable spherical shell, the propulsion system for sphere and wheeled mobile unit module. It can realize the exchange of the roles by changing spherical shell’s shape. Theoretical analyses and parameter optimization methods are used to analysis structure parameters of the transformable shell, wheels and driven pendulum. And the simulations based on the structure parameters prove the rationality of the robot design, which provides a theoretical basis for mechanical design of this mobile robot. The experiment confirms the feasibility of this mobile robot.

Key words: Mechanical analysis, Mobile robot, Structure design, Transformable spherical-wheel robot