Structural Design And Gait Simulation Of Flexible Leg Quadruped Robot

The most representative quadruped robots have gradually become a hot topic in the field of robotics since the first generation of Boston Dynamics Big Dog Robots came out.Compared with other kinds of robots,quadruped robots have many incomparable advantages,especially in the adaptability and application of special complex geographical environment,which has broad scientific research and commercial value.However,at present,quadruped robots are mostly composed of rigid components,and spring components are installed at the foot end to reduce the impact with the ground,which fails to give full play to the advantages of bionics.Based on the inspiration of bionics,flexible spine and flexible cheetah leg,a quadruped robot with flexible cheetah leg and flexible spine is designed in this paper,which provides a new idea for the design of quadruped robot.Firstly,a flexible quadruped robot with 14 degrees of freedom is designed based on the inspiration of bionics and the release of prosthetic legs.The design of robot has an active flexible spine,four legs use a flexible "cheetah leg",and the three-dimensional modeling software is used to model the components and the overall design of the robot.The structure and motion mechanism of each component,as well as the selection of the driving force are described in detail,and the flexible components are analyzed by finite element method.Secondly,the forward and inverse kinematics analysis,velocity analysis and acceleration analysis of single leg of quadruped robot are carried out by using classical D-H method.In dynamics,the rigid-flexible hybrid single leg of quadruped robot is analyzed in detail by using Euler-Bernoulli beam element model and finite element method combined with Lagrange equation.Finally,the flexible quadruped robot is simulated by Adams software.For the complex three-dimensional model of the robot,it is simplified in the Adams software.In the simulation software,the flexible quadruped cheetah-legged robot is taken as the main body,and the rigid cheetah-legged robot,the flexible L-legged robot and the rigid L-legged robot are introduced as the contrast.Motion simulation is carried out under walking gait and diagonal gait respectively.Step function and trigonometric function are used to drive the joint angle of the robot.The displacement and velocity curves of the body mass center,velocity curve,foot trajectory curves,joint driving moment function curves,foot contact force curves and foot elastic deformation curves are obtained.The curves are analyzed and compared.