High-resolution Intelligent Measurement Instrument Developed

The velocity of pill is an important index to valuate the characteristics of firearm, ammo and ballistic trajectory. So its measurement precision is very important. Now in the world, the velocity of pill is generally got by measuring the time interval when pill passes through two targets with a fixed distance. And time-measuring instrument is mainly used to measure the time interval. The time measuring resolution directly affects the precision of velocity.In this paper, an intelligent time-measuring instrument with high resolution is developed to measure the velocity of pill. The instrument includes counter module, controller circuit and PC monitoring software and so on. The timing resolution of 20 ns is realized by counter module which is based on the technology of CPLD. The data collections, communications and counter module clearing are realized by controller circuit. The core of the controller circuit is AT89C51 single chip. The data collections, real time data display, data storage and processing ,data-base inquiring, report forms display and printing are realized by PC monitor software which is based on the programming idea of modularization and developed by VB. The problem of high time measuring resolution is resoled by the time-measuring instrument developed in this paper. The instrument with friendly man-machine conversation interface can also simplify and intelligentize the operations.