【摘要】 介绍了超声波在空气中的传播原理,分析了超声波测距产生测量误差的主要原因,即环境温度变化引起速度的变化,回波前沿的确定偏差引起测量时间的误差是引起测距误差的主要原因.提出通过温度测量修正传播速度,应用双比较器整形结合软件查找回波前沿以提高空气中测量精度的方法.在此基础上,设计了相应的超声波测距系统并与单比较器测量系统进行了对比实验,研究表明,双比较器整形方法能够有效的提高测量精度,而且相对其他高精度超声波测距方法,该方法电路简单.图4,表2,参8.更多还原

【Abstract】 The principle of ultrasonic transmission in the air was described. The main error sources of ultrasonic measurement are analyzed. The main errors of distance measurement are caused by the change of the transmission speed of ultrasonic wave along with environment temperature and the delaying of forward edge of receive wave. The method of correcting transmission speed throngh inspecting temperature was introduced. A method which check up the forward edge of receive wave by regularizing in dual comparators was described. A measurement system based on the idea was designed. Comparison experiment with single comparator measurement system was carried through. Result show that the precision of dual comparators measurement method is improved obviously, contrasting it with the single comparator measurement system. The circuit of dual comparator measurement system is simpler than other high precision measurement system.4figs.,2tabs.,8refs.更多还原