自动车距保持控制系统设计

AbstractThe automatic measuring of distance is mainly used in measuring the distance of CarBacking reminding,construction sites,industrial site,etc.The application of ultrasonic testingthe distance is very widely.such as the measure of the depth of the water,the place of the fishin the sea,the metal detection,the measure of the thickness and the reverse in case of the carclashing and so on.The design requirements for the design of automatic car spacing control system,whichincludes automatic detection distance and automatic alarm function.This design usesultrasonic sensor to measure the distance.On the basis of feasibility analysis and reliabilityanalysis,a set of ultrasonic ranging system based on AT89C52 MCU is designed.Accordingto the principle of ultrasonic wave propagation in the air,the ultrasonic sensor is used tomeasure the actual distance in air.The system is mainly composed of five modules,namely,the central processing module,ultrasonic transmitter /receiver module,display module andalarm module.The design of the I/O interface module 51 microcontroller system,back to theultrasonic transducer to send out the 40kHz ultrasonic wave and ultrasonic reflection,throughan amplifying shaping circuit into the microcontroller,then debug,determine thecorresponding distance.Such kind of SCM ultrasonic distance measuring strengthen the anti-interferencecapability of the ultrasonic,reduce the error of the measurement made by man,simplify theexternal interface circuit and solute the inconvenience of the distance measure in daily life.Key words:Ultrasonic Sensor AT89C52 SCM Display module Alarm module