Abstract:

To investigate the terrain adaptability of a closed five-bow-shaped-bar linkage, capability and motion planning for obstacle negotiation are investigated. The mass center expression of the linkage about the contact angle and the active joints is deduced by homogeneous transformation through the establishment of kinematics analytical model for the closed five-bow-shaped-bar linkage. The mathematic model for maximum height of obstacles negotiation is extracted out under the condition of kinematics and geometric constraints in the process of obstacles negotiation. And also, the maximum height along with the contact angle and the radius of joint circular is figured out by using numerical algorithm. Once more, according to the concave characteristic of feasible region of the mass center, the move path for the center of mass is planned by tangent method in accordance with the shortest route strategy. Then, the trajectories of active joints are obtained by means of inverse kinematics. The correctness of the analysis is verified by experiment in a prototype finally.

Key words: center of mass, closed five-bow-shaped-bar linkage, motion planning, obstacle negotiation capability