Research On Joint Impedance Control Based On Flexible Wheel Strain Force Feedback Of Harmonic Reducer

One of the biggest characteristics of the new generation of "cooperative" robots is that the robot can coexist with others.To achieve it,the robot arm is required to be compliant,which requires that each joint is compliant.Obviously,the compliance of joints is the key to realize the whole arm compliance,and it is a core technology of the new generation of"cooperative" robot.In order to solve the problem of new generation "cooperative" robot's joint compliance control,the joint impedance control is studied based on the flexible wheel strain force feedback.The research work is supported by the National Natural Science Foundation of China " the research of the robot error modeling and calibration method based on the stiffness model(N0.51405482)" and autonomous project of the State Key Laboratory of Robotics "Key technologies of cooperative robot flexible joint(No.2014-Z09)",the main research contents are as follows.First of all,I have investigated a lot of literature,and grasp domestic and foreign research status of the relevant field.Research contents include "cooperative" robots,joint output torque detection method,dynamic modeling of harmonic drive joint and compliant impedance control method,etc.Secondly,joint torque measurement method is analyzed deeply.Based on the transmission mechanism of harmonic reducer and the characteristics of flexible wheel's periodic deformation,I have completed the design of the mounting strain gauge signal acquisition and processing circuit.This research presents a system design analysis and experimental method for measuring the output torque of the joint using harmonic flexible wheel strain.Then,the design structure of the joint module of modular reconfigurable robot arm is studied and analyzed.The torsional stiffness model of the joint module drive chain is established.On the basis of this,the dynamic model of the robot's harmonic drive joint module is established.Next,the basic principles of impedance control was studied.In order to solve the problem of adaptive adjustment of impedance parameters K and B under different operating conditions,the impedance of neural fuzzy adaptive control algorithm for the parameters of controller is proposed.Finally,a physical simulation experiment platform is designed and built to verify the compliance control method of the joints.Using this platform,system simulation and experimental study are carried out on the proposed method.The feasibility and effectiveness of the developed system and related control methods are verified.