Reconstruction Motion Analysis And Stability Control Of Wheel-Legged Metamorphosis Robot In Parking Steering

This topic combines the mobility of wheeled robot and the flexibility of foot robot to design a wheel-legged hybrid metamorphosis robot,which can switch naturally between wheeled movement and foot walking according to the external environment.This paper focuses on the kinematics and dynamics analysis,stability criteria and evaluation criteria,motion planning,swing leg landing compliance control strategy,motion stability control,construction of embedded electronic control system of the steering coupling reconstruction of the wheel-legged hybrid metamorphosis robot.Firstly,the metamorphic robot is simplified and a 12-link model is established in three-dimensional space.The kinematics model of the steering coupling reconstruction process is established based on Cartesian coordinate system and generalized coordinate method considering the coupling effect of the connecting rod in the forward,lateral and lateral plane motion.Lagrange dynamics equations are used to establish the dynamics models of the metagritic robot in the forward plane,lateral plane and lateral plane during single and double foot support.Secondly,the stability of the system steering coupling reconfiguration is analyzed based on the ZMP stability theory.The ZMP formula for the multi-link model of metamorphic robot is derived.The motion law of joint Angle was planned by cubic spline interpolation function to ensure the smooth motion of steering coupling reconstruction.Stability margin is introduced to quantitatively evaluate the stability of the system in the process of movement.Then,through analyzing the interaction between the swinging leg and the environment in the steering reconstruction process,a landing compliance control method of the swinging leg is proposed,and a position-based impedance control model was established to reduce the rigid impact between the robot and the ground when the swinging leg landed.Fuzzy PID controller is designed to control the motion law of the centroid adjusting slider,and ZMP(zero moment point)is adjusted without changing the motion law of the joint to ensure the motion comfort,so as to enhance the stability of the steering coupling reconstruction motion process and improve the anti-interference ability of the system.Finally,the electronic control system of the metamorphosis robot is developed,and the experiment platform is used to design and complete the landing compliance control of swinging legs and the stability control of steering reconstruction.The proposed control strategy is verified experimentally.