Research On Hybird Force/Position Control Of Manipulator

With the global economic developing,especially in the background of "Industry 4.0",the fourth industrial revolution of an intelligent manufacturing is underway.The robotics industry as the focus of the revolution is expanded.Manipulator assembly operations with constraints are an important part of advanced manufacturing systems.In the currently industries,such as welding,handling and spraying,manipulators that only using a simple trajectory control is not enough for complex assembly operations.The position and force also need precisely compliance control.In this paper,a large number of the basic research on the compliance control strategy in assembly tasks,especially the force / position control method in case of the presence of white Gaussian noise in force sensors has been taken.Firstly,establish kinematics and dynamic models of the 6-DOF manipulator REbot-V-6R with D-H method and Newton-Euler equations.Then manipulators simulation system is developed using Matlab / Simulink and Robotic Toolbox.Secondly,study the noise signal characteristics of the sensor,such as the amplitude frequency characteristics,power spectral density,amplitude probability density distribution.It has been gotten that the signal noise characteristics match the Gaussian white noise and the noise characteristic parameters are obtained.Then the contact model of manipulator end with the contact environment is studied.The model of the sensor adding the actual noise characteristic parameters is established and is simulated with Matlab / Simulink.Finally,study several hybrid force / position control algorithm.Design the controllers of feed forward controller,feedback controller and force/position controller based on the decomposition of speed.The torque can be computed by the inverse dynamic model.To solve the issues that the sensor noise decrease the performance of control,the method combining hybrid force / position control strategy with Kalman filter is proposed.It makes full use of the Kalman filter.Then do the trajectory and force tracking simulation experiments of static force and dynamic force on the static plane and moving plane(curved surface).And the simulation results show that the method combining hybrid force / position control strategy has a better ability to suppress the impact of noise than the classical methods.