摘要：安全避障是移动机器人或安全倒车研究的一个基本问题，障碍物与机器人或汽车之间距离的获得是研究安全避障的前提。本文提出并实现了一套基于超声波传感器的测距系统，其主要目的是为汽车的倒车、机器人自动避障行走、建筑施工工地以及一些工业现场进行实际距离的测量。本系统主要由单片机最小系统、超声波收发装置和LCD显示电路三部分组成，系统经实际组装与调试，达到了原设计要求。实验结果表明，利用单片机控制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，具有测量精度较高的特点。

关键词：超声波测距； 单片机； LCD显示； 误差分析。

Abstract: Safe obstacle avoidance is a basic problem of mobile robot or the safety reversing, the distance between the obstacles with the robot or car access to the premise of safe obstacle avoidance. In this paper, it proposed and implemented a ranging system based on ultrasonic sensors, the main purpose of reversing the car, robot automatic obstacle avoidance walking the construction site, as well as some industrial field for the actual distance measurement. The system mainly consists of the smallest single-chip system, ultrasonic transmitters and receivers, and LCD display circuit consists of three parts, by the actual assembly and debugging, to achieve the original design requirements. The experimental results show that using microcontroller to control the ultrasonic testing is often more rapid, convenient, simple calculation and easy to do real-time control features with high measurement accuracy.

Key words: ultrasonic ranging； microcontroller；  LCD display； error analysis.