Research on the structural design and motion characteristics of a self-reconfigurable spherical robot

Abstract. Traditional spherical robots usually adopt a fixed spherical shell structure, making it difficult to adapt to complex terrains such as steep slopes, obstacles, or uneven ground. Moreover, most traditional spherical robots rely on pendulum or wheel-type driving, and this single driving mode limits their applicability in diverse environments such as slippery or soft ground. This paper proposes a multi-driving-mode spherical mobile robot that integrates pendulum driving, a spatial folding–unfolding mechanism, and a rotor mechanism. It has a scaling and deforming function, breaks through the limitations of the traditional fixed-spherical-shell design, and improves terrain adaptability. It adopts single-pendulum driving and is supplemented by a rotor and wheel-train mechanism to optimize linear and steering performance. A dynamic model is established based on the Newton–Euler method, the limit parameters for obstacle crossing are studied, and design principles are proposed. The rationality of the mechanical system and the performance influence of key components are verified by Adams simulation. The tests of the experimental prototype show that the robot has excellent terrain adaptability and versatility in complex environments, providing new ideas for the development of mobile robot technology.