Research On Trajectory Tracking Control Of Industrial Robot Based On Sliding Mode Control Strategy

With the rapid development of information technology and industrialization,it is increasing the requirements for the automation.And with the development of mechanical and electronic technology and automatic control theory,the functions of robot are also gradually got improved,and more and more applications in the rapid development of the industrial field.An industrial robot is a kind of very complex system,in which the control issue is the core of all the functions of the robot,and core issue is focused on the trajectory tracking control.The trajectory tracking control is that each joint of the robot traces the time-varying and continuous trajectory to complete the tracking control.It is because of the complexity of the system and the variability of the target trajectory,it is very important to realize the fast and accurate trajectory control of the robot.In this dissertation,it is studied the trajectory tracking control of industrial robot based on sliding mode scheme with the ABB industrial robot as the controlled object,and the simulation of the robot system is carried out by the virtual prototype technology.The main contents of this dissertation are as follows:Firstly,the coordinate of each joint axis of the robot is established according to D-H method,and the homogeneous coordinates of each joint are obtained by using the coordinate transform.After obtaining the robot kinematics characteristics,Lagrange Lange equation is employed to construct the robot dynamics model,and the dynamic characteristics of the robot are investigated.Secondly,because of the high robustness of variable structure sliding mode strategy to the structure uncertainty,it possesses the unique advantage in robot issues,so in this dissertation,it deals with the robot control problem with variable structure sliding mode strategy,and the simulation study is carried out to verify the effectiveness of the control strategy.The integration of adaptive algorithm and sliding mode control strategy is applied to deal with problem of uncertainty,external disturbances and modeling errors in the robot model,the uncertainty is eliminated by identifying the unknown parameters,diminishing the approximation error.Through the design of the whole sliding mode surface,the whole sliding mode controller is proposed.To improve the control performance of the system for reaching mode,enhance the robustness of uncertainty.At the same time,a simple state observer is designed to obtain the state variables which cannot be directly measured by the designed observer.Finally,virtual prototyping technology is used to construct the virtual physical model of the robot to approach the real robot.The interface is established with ADAMS to build a joint simulation environment of MATALB and ADAMS.The ABB robot model is built in ADAMS,the sliding mode control algorithm is established in MATLAB,and the joint simulation is realized on the simulation platform.It is established,in this dissertation,the dynamic model of robot by using Lagrange method,and upon this,the robot controller is designed using sliding mode control strategy,aiming at the control issue.And the combination of sliding mode control and adaptive control is proposed together with the state observer design to upgrade the properties of the designed controller and improve its performance;finally,the physical model of the robot with MATLAB established by using virtual prototype technology to verify the effectiveness of the designed control strategy.