详细介绍了一种机器人超声测距系统，测距范围０．２～５ｍ，具体设计了基于单片机控制的３路超声测距系统的软、硬件，并介绍了该系统的构成、工作原理最后，通过实验获得３路测距数据，同时利用误差补偿的方法得到测距系统所要求的精度±４ｃｍ还给出了该单片机应用系统与上位机之间的通讯等利用本系统及其设计方法作为农业机器人辅助视觉系统，可以获得农作物远近以及大致形状等信息 A robot ultrasonic ranging system is introduced in detail. The ranging range is 0.2 ~ 5m. The hardware and software of the 3-channel ultrasonic ranging system based on single chip microcomputer are designed. The composition and working principle of the system are introduced. Finally , Through the experiment to obtain 3-way ranging data, while using the error compensation method to get the required accuracy of the ranging system ± 4cm  also given the SCM application system and the host computer communication  use the system and its design As an agricultural robot-assisted vision system, the method can obtain information about crop’s distance and approximate shape