The Design Of Active Dual-light Curtain Precision Velocity Measuring System

As the development of electronic and optical technology, light curtain velocimetry has the advantages of anti-interference ability, high precision and good repeatability; gradually replace the traditional methods and more widely used in velocity measurement. Laboratory has successfully developed a frame-light screen system, the simulation and shooting range experiments proved the feasibility of the theory. But there are also many problems to solve, the target surface area is small and not continuous, hard to install and regulation, anti-interference ability is poor. Therefore, it is necessary to improve the system.On the basis of the existing conditions,this article has developed the active dual light curtain velocity system. According to the high stability, high accuracy target, put forward the overall program to the active dual light curtain velocity system. Complete the energy analysis of the received signal and the parameters design of the optical part, according to the design requirements of a large target area, select the appropriate laser and detector. A geometric model of projectile-light curtain is proposed and the edge extraction method is used to detect the weak optical signals. The analog circuit, which consists of pre-processing circuit, the cascade filter amplifier and the rectifier circuit is designed. The noise caused by the background-light and insect is effectively filtering out. The weak effective signal extraction is accomplished. Complete the ARM-based embedded software and PC software debugging. According to the uneasy carry and inconvenient adjustment problems of frame screen system, completed the mechanical structure of the speed system design, processing and transfer. Carried out the simulation and actual experiment, the results show that the system is less affected by the environment, to meet the measurement requirements.