Design And Fuzzy PID Control Of Hexapod Walking Robot System Based On STM32

The stationarity of motion of hexapod walking robot will be easily affected by the unpredictable disturbances when it walking on the unknown terrain. In order to reduce the robot mechanical shock caused by its unstable movement, we need to adopt an appropriate method to control the position and orientation of each joint of the robot.The fuzzy PID control algorithm of the robot joints is studied aiming at improving the stability of the motion and the speed of the respond and the accuracy of the joints pose of the robot. The main content of the research of this article is as follows.Firstly, the body structure of hexapod robot has been optimized; the kinematics analysis of robot is studied; the relationship between the range of the robot motion and the pose of robot legs and robot joints variables is established. Secondly, the robot vertical and horizontal straight triangle gait are planned in this paper on the basis of the robot kinematics analysis; the method to compute the step length of the robot which can keep the balance of the robot is given in this paper; the stability of triangle gait of the robot vertical and horizontal straight walking is analyzed.During the robot straight walking, if its step length of triangle gait is shorter than the critical step length, the robot gait is stable, otherwise it is not stable. Thirdly, the design of the hexapod robot control system is researched in this paper, the hardware system including wireless communications unit, remote debugging unit, joint driving unit, touch detecting unit, the unit of detection of obstacle avoidance, direction detecting unit and the robot body vibration testing unit. The software of the robot system uses PID algorithm to control stability of the robot body. Finally, to overcome defect of the classic PID controller on robot joints control, this paper analyzes the theory of fuzzy PID control algorithm. Applying the SIMULINK function of MATLAB to set basic parameters of the controller and apply parameters to the control of the robot joints to achieve good control effect. By comparing the simulation data of PID controller and fuzzy PID controller on the response to the step signal, fuzzy PID controller has shorter transition time, quickly response, good dynamic stability. From the results of robot straight walking test of the hexapod robot, when the robot control system uses the fuzzy PID control algorithm to control the robot joints, the pose of robot walking is more accurate, the vibration of robot body is smaller, the controller can effectively reduce the robot motion impact of the inertial force and improves the quality and overall dynamic stability of robot motion process.