The Application Of Virtual Instrument In The Roundness Of Rotational Parts Test

This task study the method of intelligentize adopting modern testing technique to improve precision instrument for tradition geometrical parameter test, Which based on JJC-6 type optical diagraph which was made by Shanghai 3^rd Optical Instrument Factory.At the first place ,this article analyzed the need of precision measured technique for modern mechanical manufacturing and the actuality of use of tradition geometrical instrument, discussed the late development of modern testing technique which including main content,general situation of virtual instrument and the necessary and feasibility of improving of tradition geometrical instrument by using modern testing technique. And thus, this article took a typical optical instrument, optical diagraph, as the study object, discussed how the autocontrol mode, which is the combination of superior computer and inferior computer, do for operation by hand , and how machine vision and figure identify instead of reading result by eye, and how virtual instrument, which taking PC as core, replace manpower and hardware instrument to realize the fast dispose and assess of measured data At last, this article pointed out two effective method which aim at image dispose and figure identify for optical instrument ocular inspect, and realized them concretely.This article had tow part : hardware and software, it mainly discuss motor's drive,image's collection and the sample of outline's signal of rotator in hardware part, In software part, it put its emphasis on image dispose of optical diagraph's screen and data processing . It put forward the method of offset to eliminate the background of the screen and the method of endpoint character to identify figure in image dispose .In the part of data processing ,it discuss the theory and the theory and the course of approach method to get the error of roundness carefully.