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超声波测距仪的设计
摘要：电子测距仪要求测量范围在 0.10～5.00m，测量精度 1cm，测量时与
被测物体无直接接触，能够清晰稳定地显示测量结果。由于超声波指向性强，能
量消耗缓慢，在介质中传播的距离较远，因而超声波经常用于距离的测量，如测
距仪和物位测量仪等都可以通过超声波来实现。超声波测距器，可以应用于汽车
倒车、建筑施工工地以及一些工业现场的位置监控，也可用于液位、井深、管道
长度的测量等场合。利用超声波检测往往比较迅速、方便、计算简单、易于做到
实时控制，并且在测量精度方面能达到工业实用的要求，因此在移动机器人的研
制上也得到了广泛的应用。
该测距仪采用 NE555 电路、两级放大电路和电平比较电路实现了超声波的发
射与接收。单片机为该测距仪的核心单元，实现发射电路的控制和接收数据的处
理。本系统在 10～200cm 的距离内测量精度可达±0.5cm，并且易于调试，成本
低廉，具有很强的实用价值和良好的市场前景。
关键字：超声波传感器，测距仪，PIC16F876A
Abstract：Ultrasonic Ranging, can be used in car reversing, the construction
site and the location of some industrial site monitoring, can also be used if the level,
depth and length of the pipeline, such as measurement occasions. Measurement of the
requirements in the 0.10-5.00 m, precision 1 cm, with the measurement of detected
objects without direct contact, being able to clearly show stable measurement results.
Because of the strong point of ultrasonic energy consumption slow, medium of
communication in the longer distance, thus frequently used ultrasonic distance
measurement, such as the range finder and level measurement and so on can be
achieved by ultrasound. Use of ultrasonic testing is often more rapid, convenient and
simple terms, easy to achieve real-time control, and measurement accuracy can meet
the practical requirements of industry, in the mobile robot has been developed on a
wide range of applications.
