The Research And Development Of Control System Of Flaw Height Measuring Apparatus

The article discusses the importance of the model of flaw height measuring in the NDT, and summarizes the domestic and international tendency of present relevant subjects. On the base, the author designs a new kind of measuring instrument, which by background light source; gathers the signal of ray negative of relevant position with sensor of pen type, and carries through demising and digital filtering; it can demonstrate the height of defect directly by the model of examining defect height and software. The instrumentation has such characteristics as to be small, easy to operate, accurate to measure, and show in real time.It also introduces the density of X-ray negative and flaw height on different irradiation conditions, and discusses choice of parameters of the math formula. Through experiments, it is proved that errors of flaw height is within permission.After measurement and collection of weak sign have been researched, the way and frequency of sampling is decided and data is dealt in the present paper.The article designs a systematic program, including collecting components, designing hardware, software, AD transformation model and keyboard function model. Much work is done to enhanced the resisting interfere ability on the aspects of the hardware and software.As the research shown, the X-ray negative sign measuring instrument which sets lamp as its light source is almost efficient as expected. A experimental test has been conducted to the whole program. Besides, the result of the experiment of testing the repetition of the instrument proves that the program shows no difference with the expected research aim.