Design And Implementation Of Motion Controller For Industrial Robot ARM Based On ROS

An arm-like robot,or simply robot arm,is a very common type of robot that is commonly used in industrial automation such as assembly,welding,handling,etc..Today,the application of the robot arm is very mature,and most industrial robot arms are controlled by PLC(Programmable Logic Controller).PLC has the advantages of stable performance,high reliability and convenient programming.However,PLCs produced by different manufacturers are usually incompatible,which brings great trouble to the transplantation of the program and which reduces the universality of motion control software.Second,commercial control software typically requires a high purchase cost which therefore increases the user's production costs.ROS(Robot Control System)is a software ecosystem for robot application development.The robot application developed by it has the characteristics of good versatility,convenient porting,etc.,and it adopts open source software mode,which enables us to adopt thousands of existing open source software and algorithms,which improves the development efficiency of the application.Therefore,for industrial robotic arms,it is of great engineering value and theoretical significance to study the development of motion controller based on ROS.This paper focuses on the design and implementation of the ROS-based robot arm motion controller.The main contents are as follows.The second chapter of the thesis begins with the system perspective,analyzes the system structure of the typical robot arm motion controller and the main functions and features of each function module.Then,through the inter-process communication method provided by the ROS infrastructure,the overall software structure of the robot controller is demonstrated and designed.In order to simulate the controller in the computer,we discuss the robot modeling method based on URDF(Unified Robot Description Format)and the coordinate transformation problem of the robot in the third chapter.The fourth chapter of this paper mainly discusses the design and implementation of the robot arm controller.We use a bottom-up discussion sequence to introduce each module in the control system one by one.These include the servo controller,the trajectory interpolation module,and the kinematics forward and inverse solution module.For each module,we first study from the algorithm level,and then give its specific implementation in ROS.At the end of this chapter,we used the designed controller to control the manipulator model to perform a comprehensive task to verify the effectiveness of the motion controller.In the fifth chapter of this paper,considering the performance problem of motion control algorithm on small devices,we propose an improved interpolation algorithm based on frequency domain zero-padding,so that part of the computational load can be shared with a DSP(digital signal processor).We validate the algorithm by performing simulation experiments on a computer with a graphic card.At the end of the paper,the advantages and disadvantages of ROS-based robotic arm motion controller design are summarized,and the future research directions of the project are given.