Design And Dynamics Analysis Of Bionic Joint Driven By PAM-motor

Aiming at the problem that it is difficult to achieve precise control of manipulator joints under the conditions of flexibility and large power/weight ratio,a bionic manipulator joint driven by pneumatic artificial muscle(PAM)and motor is proposed.The parallel configuration of pneumatic artificial muscle and motor is used as the compound driving source of the joint,which can satisfy the high precision and large size under the condition of self-weight and lightweight.Bearing capacity can also meet the special requirements of flexibility,robustness and human-computer interaction.The joint structure of the bionic manipulator driven by PAM-motor is designed.The integrated system model,kinematics model and dynamic model of the joint are established.The driving mechanism,workspace and dynamic characteristics of the bionic joint are analyzed.The adaptive control of RBF neural network based on uncertain term approximation is used to simulate the bionic joint driven by PAM-motor.The specific research contents of this paper are carried out from the following three aspects:(1)Structure Design and Compound Driving Mechanism of Bionic Joint Driven by PAM-motorAiming at the contradiction between flexibility and accuracy,bearing capacity and lightweight of traditional manipulator joints,inspired by the deep research and analysis of the structure and motion of human arm joints,combined with the excellent characteristics of pneumatic artificial muscle driving source and motor driving source,a bionic joint based on pneumatic artificial muscle and motor driving is designed,and a PAM-motor driving composite joint is established.-The virtual prototype of the bionic joint driven by the motor is explored to explore the mechanism of the composite drive.(2)Kinematics and workspace of bionic joint driven by PAM-motorThrough the study of virtual prototype model and compound driving mechanism of bionic joint driven by PAM-motor and based on D-H coordinate system,the kinematics model of bionic joint driven by PAM-motor is established.The forward and inverse kinematics solutions of bionic joint driven by PAM-motor are analyzed.The correctness of the forward and inverse kinematics solutions is verified by numerical calculation and analysis,thus the rationality and operation of joint design are verified.The correctness of kinetics solution.Based on the mathematical principle of space geometry,the maximum angle range of the workspace for the reachable position of the bionic joint driven by PAM-motor is determined.(3)Dynamics of bionic joint driven by PAM-motorBased on the constitutive model and theoretical mechanics of pneumatic artificial muscle,the mechanical properties of bionic joint driven by PAM-motor were studied,and the mapping model between structural parameters and mechanical properties of bionic joint driven by PAM-motor was deduced.Aiming at the problem that the pneumatic artificial muscle has time-delay and non-linearity which affect the joint motion accuracy,the dynamic model of the bionic joint driven by PAM-motor is established through in-depth study of the Lagrangian dynamic model.The digital simulation of the bionic joint driven by PAM-motor is carried out by using RBF neural network adaptive control based on uncertainty approximation.The desired trajectory is tracked according to the position of the pitch motion and the side-swing motion of the bionic joint driven by PAM-motor.The rationality of the structure of the bionic joint driven by PAM-motor is verified.The pitch motion and side-swing motion of the bionic joint driven by PAM-motor are also verified.And the accuracy,dexterity and carrying capacity of the composite motion.