Analysis On The Passive Bounding Quadruped Of Articulated Leg

In this thesis, the passive bounding quadruped consisted of articulated leg is analyzed. Currently research of flexibility leg and quadruped are introduced and analyzed. Using data fitting method, the nonlinear stiffness characteristic of an articulated leg is analyzed. In order to analysis the passive bounding motion of the articulated leg, it is equivalent to a spring loaded inverted pendulum model(SLIP). The passive bound dynamics and the each of phase transition condition of the SLIP model are obtained using Euler-Lagrange method.Then briefly introduce some basic gaits of quadruped robot and analysis four motions phase of a cycle bounding motion. In order to analysis the passive bounding quadruped consisted of articulated leg, the equivalent model of articulated leg is used to make up a passive bound model of quadruped. Some hypotheses of the model are bring forward for analysis. The model is consisted of a body and two massless legs. Using Euler-Lagrange method the each phase dynamics of the model during the passive bounding motion and the each of phase transition condition are obtained according to bounding motion.Then the Poincarémap of passive bounding motion of spring loaded inverted pendulum model and quadruped model are derived. The Newton-Raphson method is used to find the fixed point of SLIP model and quadruped model. The fixed point is as initial motion condition to simulate the passive bounding motion of the SLIP and quadruped model by Runge-Kutta method in Matlab. Numerical method verifies the models have stability periodic motion at certain condition. .