3-DOF bionic parallel mechanism design and analysis for a snake-like robot

This paper proposes a new joint mechanism for a snake-like robot to travel in hazardous areas for rescue tasks. In a complex environment, it is necessary to preform an efficient three-dimensional motion. But, a serial snake-like robot could hardly do that because of the limitation of its 1-DOF joint structure. To meet the requirement of flexible locomotion, a parallel mechanism was proposed which was derived from the biological characteristic of snakes. The design applied a asymmetrical structure mimicking snake spines and muscles and it has the same level of dexterity compared with rotating joint. We obtain control equations for yawing and pitching angle by inverse kinematic solution. Then, the workspace is analyzed via screw theory and vector position equation. A non-model based control serpentine gait and a multiple beat rectilinear motion of snake-like robot with parallel mechanisms are introduced.