Research Of VMU432 Image Measurement Error Detection And Improvement

Usually,for error detection most traditional image measuring instruments manufacturers flow the standard "GB/T 24762-2009",use the line scale to test.It is very easy,but most testers faced some problems:low accuracy,measurement system is not stable,no guideline for root case analyzes,the direction of improvement is not accurate and the improvement process is difficult.The manufacturer must make a bad decision to remove the error assembly unit and use the new parts to instead.All of these caused the products in a high cost and delivery date is not control,improvement on customer site is difficult.This seriously restricts the rapid development of the manufacturer and the product quality improvement.Error detection and compensation is an economical and effective method to improve the precision and reliability for Image measurement.The paper studies error detection,error compensation and accuracy improvement,based on laser interferometer,two-dimensional plane grid plate for VMU432 high precision automatic image measuring instrument which manufactured by TZTEK,mainly finished the following work:(1)Analyzed the VMU432 image measuring instrument coordinate system and the main error factors.Using the homogeneous coordinate transformation,build reference coordinate system and the axis of coordinate system.Through the kinematic chain between CCD to the work table and coordinate transformation between measuring elements to kinematic chain,build the geometric error model of image measuring instrument.(2)Based on XL-80 laser interferometer,designed a test propose for plane image measuring instrument position error,tested and analyzed the equipment positioning error detection,taken an action to improve and verify.Using the laser interferometer,we can inspection the equipment axis positioning error,angular deviation,and other geometric error.According to the test results we can analyze the problem and make an improvement action immediately.At the same time,we can promote quickly through error compensation equipment precision.(3)Designed a test that for the influence of positioning error on measurement accuracy.Through the data comparison before and after the test,evaluated the positioning error of flat image measuring instrument measuring accuracy.(4)Based on two-dimensional plane grid error detection and compensation technology,analyzed two-dimensional plane grid error detection principle,designed and test the 2 d plane grid more compensation error detection and validation test.Test results show that application of two-dimensional plane grid plate detection and compensation plane image measuring instrument error is feasible,and the method is simple,efficient,it is suitable for measuring instrument manufacturer of batch production process control.The result shows that the positioning error directly affects the accuracy of measurement instrument;we can use laser interferometer,two-dimensional planar grid to inspect and analyze the error elements,targeted to improve.Through experiment,it shows that the proposed approach is adopted to improve the error detection,analysis,compensation and improve can effectively improve the accuracy of image measuring instrument.