基于STC89C51的超声波液位检测系统设计

Design of ultrasonic liquid level detection system based on STC89C51

为了实现液位的非接触式以及智能化测量目标,设计出了一种基于超声波测距原理的液位在线检测系统,系统由STC89C51单片机最小系统、HY-SRF05超声波测距模块、DS18B20温度测量补偿模块、LCD1602液晶显示模块以及一个声光报警模块组成。针对超声波液位检测过程中温度对声速的影响以及声波传播过程的精确计时等问题,以STC89C51为控制核心,利用其定时计数功能实现声波传播的精确计时,采用DS18B20温度测量模块对声速进行校正,在LCD1602液晶显示模块上实时显示系统安装位置到被测液体的距离值Distance以及此时的液位Level,若测量值不在所设定的范围内则进行声光报警。实验表明该系统能够实时检测液位,并进行实时显示,在测量范围内存在1~2 cm的误差,若液位不在所设定的范围内,能进行声光报警,达到了预期的目标。

In order to achieve the non-contact and intelligent measurement targets of the liquid level,a liquid level on-line measurement system based on ultrasonic distance measurement principle is designed.The system consists of a STC89 C51 single-chip minimum system,HY-SRF05 ultrasonic ranging module,DS18 B20 temperature measurement compensation module,LCD1602 liquid crystal display module and a sound and light alarm module.Aiming at the problems of the influence of temperature on the sound speed and the accurate timing of the sound wave propagation process in the ultrasonic liquid level detection process,the system uses STC89 C51 as the control core to accurate timing of sound wave propagation with its timing counting function and the DS18 B20 temperature measurement module is used to correct the sound speed.After relevant calculation,the distance value of the system installation position to the measured liquid is displayed in real time on the LCD1602 liquid crystal display module.If the measured value is not within the set range,the sound and light alarm module will be activated.The experimental verification shows that the system can detect the liquid level in real time and display it in real time.There is an error of 1~2 cm in the measurement range.If the liquid level is not within the set range,the sound and light alarm module will be activated,which is achieved the expected design goals.