摘要
在传统超声波测距基础上,结合硬件和软件两方面的控制,提出一种高精度超声波测距系统。在超声波发射部分创新性地使用MAX232芯片,缩小盲区;在信号放大部分添加时间增益补偿(TGC)电路,有效地解决了远距离回波信号过于微弱而导致系统测量量程减小的难题;在接收部分采用双电压比较器整形电路并结合软件设计纠正回波前沿的方法来提高测量精度。同时在硬件上增加温湿度传感器SHT11,采取声速预置和媒质温度测量相结合的办法对声速进行修正,实现实时声速测量的功能,以降低声速变化对测量的影响。实验表明,该测距仪的设计能够实现减小盲区,增大量程(2cm—4m),量程范围内误差控制在6mm以内的高精度测距要求。
A high accuracy ultrasonic distance measurement system is presented.based on the combination of both hardware and software controlling on the basis of the traditional ultrasonic ranging.MAX232 was used innovatively in ultrasonic transmitter and blind spots were reduced.And a time gain compensation（TGC） circuit was added in the part of signal amplification,which solved the problem of weak distant echo that led to reduce system measurement range.Besides,the measurement accuracy was increased through using dual voltage comparator circuit combined with software design to correct the front of echo.At the same time,a temperature and humidity sensors SHT11 was increased to realize real-time velocity measurement function and reduced the affect on measurement in the the hardware,and the speed of sound was corrected by presetting the speed of sound combined with medium temperature measurement method.The experiment showed that the design can reduce blind spots and increase range（2 cm—4 m）,and the error is controlled in 6 mm within the measurement range.
出处
《科学技术与工程》
2010年第30期7447-7453,共7页
Science Technology and Engineering
