發(fā)布時間：2018-11-29 08:05

【摘要】：雨量計是一種用來測量一段時間內降雨量的儀器,普遍應用于氣象、水利和農業(yè)等部門,給各部門提供用于預報和研究的降水量數(shù)據(jù)。目前國內氣象領域應用的雨量計精度和自動化程度比較低。國外的光學雨量計精度高,但價格昂貴,難以推廣普及。為設計出低成本、低功耗和高精度的超聲雨量計,本文對傳統(tǒng)的超聲雨量計進行硬件和軟件算法的優(yōu)化。硬件方面,本文選用低功耗和高性價比的STM32作為主控芯片。超聲測液位模塊由超聲發(fā)射和接收組成,發(fā)射部分通過高電壓脈沖來驅動超聲探頭,接收部分包括信號放大、濾波和整形電路。本設計采用PT100測溫,選用24位高精度AD7794進行模數(shù)轉換,溫度測量精度可達±0.05℃。同時創(chuàng)造性的對雨量計進行氣壓補償,使其適用于更復雜的環(huán)境。氣壓模塊采用BMP180組成陣列式結構,減小因傳感器蠕變導致的系統(tǒng)誤差。本設計既可以通過VFD屏顯示數(shù)據(jù)也可以通過串口將數(shù)據(jù)發(fā)送到上位機。軟件算法補償方面,本文采用L-M算法實現(xiàn)超聲速度與溫度和氣壓之間的曲面擬合,達到溫度和氣壓補償?shù)哪康摹榱朔奖阌^測者使用,本文開發(fā)了基于Qt的配套上位機軟件。本文研發(fā)的超聲雨量計量程為0-500mm,采集頻率可調。溫度適用范圍為0℃～50℃,氣壓適用范圍為500hPa～1100hPa。本設計具有低功耗模式,能夠長期在野外使用。性能測試表明,本設計測量雨量誤差±0.5mm,總體上滿足氣象行業(yè)要求。
[Abstract]:Rain gauge is a kind of instrument used to measure rainfall for a period of time. It is widely used in meteorological, water conservancy and agriculture departments, and provides precipitation data for prediction and research. At present, the precision and automation of rain gauge used in the field of meteorology in China are relatively low. The precision of optical rain gauge abroad is high, but the price is expensive, so it is difficult to popularize. In order to design a low cost, low power and high precision ultrasonic rain meter, this paper optimizes the hardware and software algorithms of the traditional ultrasonic rain gauge. In the aspect of hardware, STM32 with low power consumption and high cost-performance ratio is chosen as the main control chip. The ultrasonic liquid level measurement module is composed of ultrasonic transmitting and receiving. The transmitting part drives the ultrasonic probe by high voltage pulse, and the receiving part includes signal amplifying, filtering and shaping circuit. In this design, PT100 is used to measure temperature, 24 bits high precision AD7794 is used for analog-to-digital conversion, and the precision of temperature measurement is 鹵0. 05 鈩，

本文編號：2364432