Research On Positioning Precision Calibration System Of Industrial Robot

In recent years,with the wide application of industrial robots in various kinds of production,the positioning accuracy of industrial robots has been put forward higher requirements.The calibration of the industrial robot can reduce the error between the actual joint parameters and the ideal parameters or the internal kinematics model error caused by the small offset of the single joint of the robot,so as to improve the overall accuracy of the industrial robot.In view of the present industrial robot calibration measurement equipment cost is high,the environmental requirements higher,we design a calibration system based on dual PSD,the calibration system can not only calculate the offset parameters of the robot joint,and able to robot calibration of workpiece coordinate relations at the same time,compared with other traditional methods,has advantages of simple structure,stable and reliable,the price is cheap.The specific research work is as follows:First of all,the industrial robot localization precision calibration system is divided into two parts of hardware and software design,this paper proposes a dual PSD position sensitive calibration method,the calibration device is mainly composed of two mutual into 120 ° of the location of the sensor,use the Visual Studio tools using c # programming language WinForm made PC user interface,combined with the industrial robot manipulator,industrial camera and attached on the robot tool center point of the laser calibration system of the whole,for the follow-up industrial robot localization precision calibration system experiment laid a solid foundation.Secondly,the calibration principle of the system is analyzed and the kinematic modeling of the robot is modeled.The parameter identification and compensation algorithm as well as the servo controller of the calibration system are designed.Taking the IRB120 ABB robot as the research object,the kinematics model was established by using d-h parameter method,the forward and inverse solutions of the robot kinematics were calculated,and the robot kinematics model was verified by using the robotics toolbox in MATLAB to ensure the correctness of the robot model and provide theoretical basis for subsequent research.Then,the industrial robot joint offset parameter identification algorithm is studied,by solving the offset value in robot original model,and use Levenberg-Marquardt algorithm for parameter identification,robots was established by applying the Matlab IRB120 three-dimensional computer model,and use the initial joint excursion of the calibration parameters on joint algorithm are simulated,and compared with traditional calibration prove the validity of the new method;A hybrid servo controller based on vision and PSD is designed,which can automatically align the laser line with the two PSD,and convert the image features in the camera into the position features of the robot and return them to the upper computer.Finally,the precision calibration system platform of industrial robot is built,and the parameter identification and compensation experiments are carried out.First feedback experiment was done to double PSD position sensitive device,prove the feasibility of the device,through the software interface to read identification data,collected industrial robot joint error,error compensation experiments,the result of the identification of single and dual PSD PSD has carried on the contrast experiment,proves that the dual PSD system calibration accuracy is higher,more stable.