Research On Key Technologies Of Force/Position Control Of Robotic Manipulators Based On Impedance Control

Along with the implementation of the |industrial 4.0" in Germany and the implementation of |china made 2025",a major strategic plan of china.The Robotic Manipulators has been used rapidly in all walks of life.In the past,The Robotic Manipulators only be used to do the work that can be done by the position control functionality,such as Handling and Palletizing.But now,Robotic Manipulators is more and more used for grinding,assembling,medical operations and so on,which need to control the end position and the contact force of Robotic Manipulators.That is force/position control of Robotic Manipulators.In this paper,several current main control strategies are compared,The research is focused on the impedance control based on position,Analysis the problems of the existing technology in the practical application,Find a strategy to solve this problem,Build an experimental platform and verify the algorithm.First,Analyze the structure of Robotic Manipulators with six degree freedom,The D-H method is used to establish the coordinate system of the Robotic Manipulators and to find the Positive kinematics solution,The Inverse kinematics of the Robotic Manipulators is solved by the method of separation of variables.Secondly,Using ROS to develop the control system of The Robotic Manipulators,Establishing the URDF model of The Robotic Manipulators,Using MoveIt! to complete the trajectory planning of The Robotic Manipulators,Using rviz interface to control The Robotic Manipulators in the simulation of Gazebo.Using the underlying communication development framework(ros_control)under ROS and developing a modular joint driver based on CANopen protocol.And use the API interface provided by move_group for programming experiment.Then,Sketch the principle of impedance control,The influence of the change of the environmental stiffness and the uncertainty of the environment position on the impedance control is derived through the formula,Introducing adaptive control algorithm into the design of impedance control system,Enhance the adaptability of the system under environmental changes,According to LYNAPNOV principle,the rule of parameter adjustment is obtained.Design the adaptive impedance control system.Last,The simulation model of impedance control system is set up under MATLAB,Analyze the characteristic of impedance control parameters,Set up an experimental platform for plane force tracking,Design impedance controller,It is proved that the impedance control system with fixed parameters will lower the precision of force tracking and result in instability of the system when the environmental stiffness changes.The shortcomings of the fixed parameter impedance system compared with the adaptive impedance control system are verified by simulation.Set up an experimental platform for surface force tracking,Combining surface prediction and adaptive algorithm design control system,it is proved that the system can adapt to the uncertainty of environmental stiffness change and position,and the robustness of the system is good.