Kinematics analysis for the leg mechanism of a wheel-leg hybrid rescue robot

A novel wheel-leg hybrid rescue robot is proposed and the design is given from the 3D modularization concept. The proposed hybrid robot provides great mobility in rough and unstructured terrains, with a simplified mechanism. It can be used in a variety of dangerous and dirty tasks, such as earthquake, nuclear release and other catastrophe disaster. The legs of the hybrid rescue robot equipped with a (2-UPS+U)R series-parallel mechanism is designed. This makes the robot has a high payload capacity and great stiffness on both leg mode and wheel mode. The mathematical model of each leg is established and its degree of freedom is solved. In addition, the inverse position of the leg is analyzed and deprived using the vector method. Finally, the workspace of the leg is developed using MATLAB software. The study of the hybrid robot lays a theoretical foundation for future development of the dynamics, control system design, and the development of the prototype.