超精密超声波测距装置设计

Design of Ultra-precision Ultrasonic Ranging Device

采用特殊的3段式发射脉冲串以在回波信号中形成明显凹坑,设计了一种超精密超声波测距装置,并提出了一种适合嵌入式系统实时处理的包络提取简化算法,通过寻找回波包络的凹坑位置实现超声波飞行时间的准确测量,利用ARM+FPGA架构的SoC作为处理核心完成了样机研发。测试结果表明:在500 mm量程下典型测量误差小于0.1 mm,且在-30~65℃范围内测量精度保持稳定。

Aspecial three-section pulse train is chosen as transmission waveform,then an ultr-aprecision ultrasonic ranging device is designed.A simplified envelope extracting algorithm for real-time processing of embedded system is devised,and the ultrasonic time of flight was accurately measured by finding the position of the pit of the echo envelope.The prototype is developed by using SoC based on ARM+FPGA architecture as the processing core.The test results show that typical measurement error is less than 0.1 mm in the range of 500 mm,and the measurement accuracy remains stable in the range of-30~65℃.