防触电测距报警系统的设计与实现.docVIP

摘 要 超声波测距是一种有效地非接触式测距方式。本文在研究分析超声波原理的基础上，利用单片机STC12C5410AD作为核心控制器，设计了一种防触电超声波测量距离报警系统。本系统通过每次发射10个宽度为时间T的脉冲，同时开启定时器并延时一段时间，超声波传感器接收到回波信号经前置放大电路、带通滤波电路、后级放大电路和电压比较电路后，向单片机发出外部中断信号，单片机保存定时器的值,计数器重新开始计数。用渡越时间法计算出每根电缆线的距离，液晶用来显示所测距离，如果距离小于2m，报警电路实现声光报警。另外，由于超声波在不同温度下传播速度不同，为了提高精度使用DS18B20测出实时温度，计算出不同温度下超声波速度值，进行温度补偿。 本设计的防触电测距报警系统能够在90°，3m范围内测量多根电缆线，测量值由数字存储并进行液晶显示。精度可达5mm，并能根据电缆线的不同距离发出不同的声光报警，同时通过温度补偿提高测量精度。它具有成本低，非接触，速度快，操作方便等优点，有着广泛的应用前景。 关键词：超声波传感器；测距；STC12C5410AD；高精度 Abstract The ultrasonic distance measurement is an effective non-contact ranging. On the basis of the principle of research and analysis of ultrasonic the microcontroller STC12C5410AD as the core controller, the design of an electric shock ultrasonic measurement from the alarm system. The system each time you launch the width of 10 for the pulse of the time T, turn on the timer and delay period of time, the ultrasonic sensor receives the echo signal by the preamplifier, band-pass filter circuit, after the class amplifier and voltage comparator circuit, the external interrupt signal is sent to the MCU, the MCU to save the timer value, the counter starts counting again. Transit time method to calculate the distance of each cable, LCD used to display the measured distance, if the distance is less than 2m, the alarm circuit to sound and light alarm. In addition, because the ultrasound at different temperatures under different propagation velocity, in order to improve the accuracy of the use of DS18B20 measure real-time temperature to calculate the ultrasonic velocity values ??at different temperatures, the temperature compensation. The design against electric shock ranging alarm system in a 90 °, measured within a 3m range of cable lines to the measured value by the digital storage and LCD. Accuracy of up to 5mm, and according to the different distances of the cable to send a different sound and light alarm, and temperature compensation to improve the measurement accuracy. It has low cost, non-contact,