基于300kHz超声波换能器的高精度测距装置  

High Precision Distance Measurement Device Using 300 kHz Ultrasonic Transducer

作　　者：王英健[1] 张柳[1] 

机构地区：[1]长沙理工大学电气与信息工程学院,湖南长沙410076

出　　处：《仪表技术与传感器》2014年第1期37-40,46,共5页Instrument Technique and Sensor

摘　　要：超声波测距具有一系列优点,但因其易受工作环境的影响,难以达到较高的精度.文中在分析引起超声波测距误差主要成因的基础上,选用300 kHz超声波换能器作为超声波收发元件,采用MSP430F235单片机作为主控器,其钟频达到16 MHz,以提高系统计时精度,并采用DS18B20作为温度补偿测量器件设计了一款测距装置.此外,文中提出了一种按回波脉宽估算回波滞后时间的方法,该方法测量和计算均很方便,可在不增加过多硬件和软件开销的情况下,提高测量精度.实验表明：在0～600 mm的测量范围内,以空气作为声波传媒,反射面为玻璃、柴油、机油、沥青和水等具有良好反射性能物质的条件下,其测量精度＜±l mm.该设计实现的超声波测距系统具有高精度低功耗、电路简单、数据处理方便等特点.适用于各种液位和具有良好反射面距离的高精度测量.Although the distance measurement using ultrasonic transducer is provided with a lot of advantages,but it is difficult to achieve a high precision because it is subjected to work environment.After analysing the sources of error,the 300 kHz ultrasonic transducer was selected as the transceiver,the MSP430F235 microcontroller with 16 MHz clock frequency was used for the master controller for the purpose of improving the measurement precision of time,and the DS18B20 digital temperature sensor was used to do the temperature compensation.Furthermore,a new method which can make the hysteretic time testing more convenient is presented to detect the edge of the echo.Experiments show that the precision of distance measurement in the range of 600 mm can be less than ± 1 mm,using atmosphere as the media and glass,diesel,machine oil and asphalt as the reflector.The designed distance measurement device has the advantages of simple,high precision and low power consumption.It is suitable for various of industry high precision measurement for the liquid level and the others with a well reflector.

关 键 词：超声波 高精度测距 300 kHz超声波换能器 误差成因 

分 类 号：TP216.1[自动化与计算机技术—检测技术与自动化装置]