Research On Balance Control Of Quadruped Robot Under External Impact Disturbance

The legged robot has strong movement flexibility and environmental adaptability,and can relatively easily enter more complex on-site environments,such as earthquake sites and mountain jungles.As an important branch of legged robots,quadruped robots have broad application prospects in many fields such as military,commerce,and entertainment.Therefore,they have received widespread attention from scholars and have been greatly developed in recent years,especially in the United States.The advent of the Big Dog robot of Boston Dynamics has pushed the theoretical research of quadruped robots to a new level.As an emerging technology,it is very necessary for the country to strengthen the research on quadruped robot control technology.This article refers to the classic design structure of quadruped robots at home and abroad,and simplifies the complete hydraulic quadruped robot step by step based on the analysis of bionics and biological motion dynamics of quadruped mammals.Based on the control of the previous spring-loaded inverted pendulum model,this paper analyzes the control method of the plane three-bar model by decomposing the degree of freedom of the fuselage,and then further decomposes the motion of the three-dimensional model into the sagittal and coronal planes.Exercise,extend the control method to the three-dimensional straight leg model.By analyzing the mapping relationship between the multi-joint leg structure of the quadruped robot and the three-dimensional straight-leg robot model.Realize the motion control of the quadruped robot.In order to improve the motion stability of the hydraulic quadruped robot in complex terrain and the presence of lateral disturbance,this paper designs the balance control strategy of the quadruped robot in the walking trot gait.By analyzing the shortcomings of the commonly used trajectory planning control on the transmission robot,Combined with the motion control method of the quadruped hydraulic robot,the control strategy of controlling the yaw and roll of the robot body through the two swing degrees of freedom of the hip joint of the robot leg is improved.And on this basis,the control method of the two-dimensional virtual model is extended to the three-dimensional quadruped robot,which improves the anti-side disturbance ability of the original control method.In the simulation research,the four-legged robot's ability to walk in complex terrain and the ability to quickly recover under lateral disturbance is verified.Finally,on the basis of the simulation experiment results of the quadruped robot,the structure design of the quadruped robot is improved.Then,by building a hydraulic quadruped robot prototype experimental platform,the robustness of the quadruped robot to external disturbances when walking on a flat ground and stepping on the spot was tested,and the feasibility of the algorithm was verified.