智能公路画线车超声测距定位系统的开发与研究

Development and Experiment of Ultrasonic Ranging System for Road-lineation Vehicle

开发了用于公路画线车定位的超声波测距系统。系统由超声波测距模块、DSP、温度补偿模块、LCD和键盘等5部分构成，超声波测距模块采用超声专用芯片LMl812，以TMS320LF2407单片数字处理器控制超声波的发送和数据采集，通过回波时间计算并确定画线车相对参照物的距离及位置。通过试验确定超声测距系统的有效测量范围为60～700cm。超声探头的安装高度严重影响系统的测定结果，对于110cm高的护栏，超声探头的适宜安装高度为100～110cm。在100～700cm范围内，超声测距系统的相对测量误差小于5％，可以满足公路画线的要求。

An ultrasonic ranging system for road-lineation vehicle was developed. The ultrasonic ranging system consists of an ultrasonic module, DSP, temperature compensating module, LCD and keyboard. LM1812 was adopted to transmit and receive ultrasonic wave information. The digital signal processor TMS320LF2407 was used to control the ultrasonic system, select and process data. The distance between road-lineation vehicle and the reference objective was calculated based on reflecting time of ultrasonic wave and thus the accuracy position of the vehicle was determined. Experimental results showed that the measuring range of ultrasonic ranging system was 60 - 700 cm. Installing height of ultrasonic wave probe affected the measuring result. The optimum installing height of the proposed ultrasonic ranging system was from 100 cm to 110 cm when the reference object was 110 cm high. The relative measuring errors of the ultrasonic ranging system were less than 5% in range of 100 -700 cm, indicating that the developed ultrasonic ranging system could meet the requirements of road-lineation.