Gait Planning And Feedback Adjustment Of A Biped Robot And Its Experiments

Biped robot has some human's similarity,and is concerned with mechanics,materials,machinery,computer science and other disciplines.It has been a cutting-edge research direction and a research hotspot.Gait planning and control of biped robot is one of the most important research directions.This thesis mainly focuses on the gait planning and feedback adjustment of a biped robot.Moreover,experimental verification is also carried out by a physical biped robot driven by steering motors with the height of about 73cm and virtual prototype.In the process of prototype development,the mechanical structure is optimized,and the software system is built.According to the biped robot prototype,a seven-link model of the biped robot has been established,and the positive and inverse kinematic models of the decoupled lateral and forward plane are established.A simplified table-cart model is established,and the centroid trajectory of the robot is calculated by the preview control method.The ZMP planning trajectory is optimized by adding the preview preparation period and biped support period.The lateral plane centroid compensation model is proposed to compensate the centroid error between the robot and the table-cart model in the lateral plane.The trajectory of the robot's ankle is planned by the cubic spline interpolation method,and the joint angles are calculated by the inverse kinematics model.Using FSR(Force Sensing Resistor)mounted on the sole of the feet to detect centroid offset after the robot is subjected to unbalanced forces,re-planning the ZMP trajectory,using the preview control method to generate the centroid trajectory,and then calculating the center trajectory of the hip joint,and then the gait of the robot could be adjusted.An IMU(inertial measurement unit)mounted parallel to the sole of the foot is used to detect the pitch angle and the roll angle,and the two motor angles of the ankle joint are adjusted according to the angle feedback information so that the robot foot is in a horizontal posture.In the ADAMS simulation environment,the virtual prototype of the robot is built,and the MATLAB-ADAMS co-simulation environment is built.The data communication between MATLAB and ADAMS is realized.In the virtual prototype,the fixed step length and different step length walk simulation experiment and the gait adjustment simulation experiment under the condition of unbalance force are carried out.The walking experiment and the foot adjustment experiment under the condition of the unbalance force and the foot leveling experiment are carried out in the physical robot The experimental results show the effectiveness of the gait planning method and the lateral plane centroid compensation model,and the effectiveness of the gait adjustament under the condition of unbalance force and the foot leveling of the robot.