Design Of Automatic Calibration System For Time Grating Displacement Sensor Based On PMAC

As a new type of angular displacement sensor,time grating displacement sensor is being used more and more widely.Error calibration is a very important step in the production process of time grating displacement sensor.According to the national standard "Calibration Specification for Photoelectric Shaft Encoders(JJF 1115-2004)",time-grating displacement sensor must be verified by accurate precision when leaving factory,and products included the product test results.At present,the whole week error of time-grating displacement sensor is manual photoelectric autocollimator and manual reading data,manual calculation error.But due to the heavy workload,there are a lot of repetitive operation steps that loading errors,as reading error ?omission and so on.All of these lead to low efficiency and poor quality of calibration.In order to improve the manual calibration problems,this project design automatic calibration system based on PMAC time-grating.The system is based.NET as a platform for software write control interface to display the data collection and processing the data,control signals feedback signal acts on the PMAC to achieve the purpose of accurate positioning motor.Therefore,the automatic calibration of time grating is realized.In this paper,studied the working principle of the grating,and analyzed the error sources.Finally choose.NET as the development platform.According to the relevant provisions of state for sensor calibration,and select combining Prism with the autocollimator for calibration mode.Through the analysis of data transmission interface working mode of collimator and learning control principle autocollimator comes with software,found ways to gather its data and transmission protocols.By analyzing the characteristics of direct drive motor,PMAC is selected as the direct drive motor control device,which can effectively reduce the transmission error.Then,the control system using library function.NET acquisition data of time grating displacement sensor and autocollimator.And write the data processing module to complete the error processing of the collected data.Finally,the control of the control system is completed by the cooperation of the upper computer and the lower computer.The experiment was carried out by building the experimental platform.The automatic calibration system of time grating based on PMAC can quickly andaccurately complete the error calibration,and after calibration,the error of the grating is 0.43?.