Analysis Of Slope Moving And Running Of Quadruped Robot With Flexible Spine

The quadruped robot has good moving flexibility and environmental adaptability.In the future,the quadruped robot will enter human life and bring convenience to people in all aspects.Therefore,the quadruped robot has become one of the research hotspots.For the quadruped robot to truly serve human beings,it is necessary to design appropriate mechanical structures and efficient and stable control methods to ensure that the quadruped robot can adapt to various terrains in actual life.This article focuses on the slope moving and running of quadruped robots in actual moving,studies these two aspects,and improves the performance of the robot's slope moving and running through two innovations in mechanical structure and control methods.The specific content is as follows:(1)A four-legged robot with a flexible spine is designed.The flexible spine uses two rubber rods,and a hydraulic cylinder is arranged below the spine to control the spine bending.The kinematics and inverse kinematics of the robot legs were analyzed to obtain the relationship between the coordinates of the end of the feet and the angle of the joints of the legs.The maximum step length of the legs was obtained by using a random function method.(2)In order to improve the stability of the robot's slope movement,a method for adjusting the slope movement posture based on a flexible spine is proposed.That is,the distance between the front and back of the foot is increased by the "concave"curvature of the spine,and adjust the center of mass position by adjusting the initial position of the hip joint,so that the center of mass extension line is located at the middle position of the front and rear leg support surfaces.Then adjust the foot end trajectory,and analyze the stability.Finally through simulation experiments,it is confirmed that this method is beneficial to improve the stability of slope movement.(3)In the running movement of the robot,it is difficult to guarantee the stability of the robot.For running movement,this paper adopts the control method of central pattern generator(CPG)with feedback.Build a control network for a quadruped robot with a flexible spine,and then add feedback to each Hopf oscillator model to detect the pitch and yaw angles of the robot during running and feed it back to each Hopf oscillator model.Each Hopf model changes the amplitude of the oscillator output curve,adjusts the swing state of the robot's legs,and then changes the running posture of the robot.The simulation proves that the method helps the robot to achieve stable running motion.