Research On Position Domain Control Of Six-joint Robot Based On LinuxCNC System

In the context of the rapid development of intelligent manufacturing,the research on high-precision motion control of industrial robots has attracted more and more attention.Highspeed and high-precision has become the development trend of today's industrial robots.China's independent research on core robot technology,including robot high-precision control systems,is the only way for China to speed up industrial transformation and upgrade,and also make the manufacturing industry intelligent and digital.At present,the contour tracking error of most multi-axis CNC machine tools and multijoint industrial robots in China is still a common problem.In the contour tracking process under multi-axis linkage,ensuring the good tracking performance of each joint separately does not guarantee the ideal contour tracking error.On the other hand,for a multi-axis robot system,when two or more joints must move in a coordinated manner,the synchronization of the motion is particularly important.Under this background,it is of great significance to propose a new control algorithm to reduce the contour tracking error.This paper analyzes in detail a motion control algorithm applied to the LinuxCNC numerical control system to reduce the end contour tracking error.Combining the existing kinematics,dynamics and traditional PD control theory of industrial robots,a LinuxCNC-based system is proposed.A six-joint robot position domain control algorithm is applied to the HSR-JR605 Huashu robot to perform experiments to verify the validity of the theory.First of all,based on the traditional time domain control,this paper leads to the theory of position domain control.By determining the master-slave relationship,the motion is expressed as a function of the reference motion,and the concept of relative derivative is introduced.Finally,the dynamic model of the position domain of the multi-degree-of-freedom nonlinear robot system is derived.Then this paper combines the PD control theory,analyzes the position domain PD control model and formulates the overall plan of the position domain PD control,in which the key issues such as the master-slave axis determination scheme in the position domain control system are elaborated.Then this paper determines the hardware and software platform for PD control in the location domain.By loading components through the HAL layer,the position domain control algorithm of the six-joint robot is designed and implemented on the LinuxCNC system.Finally,this paper gives an experimental verification of whether the position domain control can improve the contour tracking performance of the end of the six-joint robot.Build a six-joint robot experimental platform,select different contour trajectories,and compare the contour tracking accuracy of the terminal in the time domain PD control and position domain PD control,and draw corresponding conclusions.Experiments show that the position domain PD control system proposed in this paper has a significant effect on improving the accuracy of the end of the six-joint robot.