Analysis And Design Of A Quadruped Robot Based On Four Degree Of Freedom Parallel Leg

Legged robot has become one of the hotpots in the research field of the robotsdepending on its super ability to adapt and the advantages that other ground propulsion donot have. Among all the legged robot, the quadruped robot have a glamorous future inemergency rescue, disaster relief, space exploration, military and entertainment because ofhigh loading capacity and good stability.A new kind of quadruped walking robot with parallel legs is proposed in this paper.Firstly, the mechanical structure of the quadruped robot is designed and the models of thesingle leg and the entire walking robot are built up. At the same time, the degree offreedom is analyzed and by establishing the restrict equation according to geometricalquality of the mechanism, the inverse and forward position is solved. At last, the numericalverification is carried out.Secondly, the performance of the single parallel leg mechanism is analyzed, whichincludes workspace analysis, singularity analysis and the Velocity/Force dexterity analysis.The boundary and the section maps of the workspace in the specific pose are drawn assame as the influence curves which present the effects of mechanism parameters on theworkspace volume. Before analyzing the singularity analysis and the dexterity analysis,the Jacobin matrix is solved through the vector derivation method and a group of thevelocity/force transmission dexterity degrees are drawn in space distribution within theboundary of workspace.Thirdly, the evaluation index of stability of the quadruped robot designed with theparallel leg mentioned above is given through the analysis of the stability. Meanwhile, thewalking gait in static condition is planned, and an effective foot trajectory of the single legmechanism is planned by the method of composite cycloid trajectory planning.Finally, both the single parallel leg and the quadruped walking robot with parallelmechanism are simulated by ADAMS, and according to the simulation, we can gain thecurves of the actuator displacement, velocity, acceleration and driving force. It lays afoundation for the following research of the quadruped walking robot.