Research On Error Analysis And Compensation Method Of Four-Axis Blade Measuring Device

With the rapid development of science and technology,non-contact measurement has become an indispensable part of the machinery industry.This topic studies the advantages and disadvantages of the traditional coordinate measuring machine and the principle of laser measurement to design a four-axis blade measuring device.Taking the designed blade measuring device as the research object,the static error and dynamic error of the device are analyzed.The error model is established by the combination of homogeneous coordinate transformation and multi-body system theory to compensate the device and reduce the static geometric error of the device.The improved digital integration method is used to reduce the interpolation error and the neural network PID algorithm reduces the dynamic control error of the device,so as to improve the measurement accuracy.The advantages and disadvantages of the traditional coordinate measuring machine and the principle of laser measurement are studied.Based on the research of fixed bridge coordinate measuring machine,a four-axis blade measuring device is designed.The device design includes the following parts: mechanical system and electrical system.,Control System.The mechanical system includes three moving shafts and one rotating shaft.The moving shaft adopts a ball screw transmission mode.The rotating shaft uses a motor to drive the worm to move.The electrical system includes the selection of the motor,the driver,the encoder,the grating,and the limit switch.Drive power supply,etc.,a brief introduction to the selection of key components and servo components of the device;the control system uses the Raytheon motion control card as the control core,and the VB software is used to compile the PC control software to convert the programming language into pulses.The command controls the motion of the motor.After the design of the measuring device is completed,the error source analysis of the device is needed.The error sources include static geometric error analysis,dynamics and control error.The static geometric error can be compensated by establishing an error model including the integrated error model and the error element model.The multi-body system theory is used to analyze the motion relationship of the device to establish a spatial error model to determine the error compensation amount.The polynomial theory is used to model the error elements to verify the fitting effect of the error data.The two methods of error compensation are error prevention method and software compensation.Through the error element model and error comprehensive model,the software compensation method is used to improve the accuracy of the device.Then the dynamics of the analysis device and the source of the control algorithm error improve the traditional PID control.In the traditional PID control algorithm,the feedback channel is added,and the neural network PID algorithm is used to improve the control performance of the device,reducing the dynamic and control errors.The integral method,from the improved simulation results,shows that the conventional digital integration method reduces the error of 0.64 pulse equivalents and improves the interpolation accuracy.Finally,the accuracy of the blade measuring device is verified.The joint measurement method along the section line normal is used to measure the blade as a whole.The method of controlling the string height is used to divide the line of the cut line,and the measurement data is used three times.The spline curve is fitted,and the accuracy of the measuring device is verified to be 0.05 mm,which meets the design requirements.