An Automatic Weather Observation System Design With Raindrop Measurement Functionality

The automatic weather station is an important meteorological observation system that can observe six common meteorological elements such as temperature,humidity,pressure,wind speed,wind direction,and rainfall,and can also increase observations by adding other sensors to the system.Raindrop spectrum,as an important content of meteorological observation,is very important for warning natural disasters such as flash floods and for cloud precipitation studies.However,due to the high cost of traditional optical raindrops observation instruments,their application in automatic weather stations is severely limited.Based on this application requirement,a low-cost raindrop spectrum sensor is designed.In order to achieve a more complete surface weather observation function,this article also designed an automatic weather station system,using STM32 processor and high-precision low noise signal conditioning circuit to achieve the hardware circuit design,in addition to the raindrop spectrum parameters,also achieved temperature,humidity,wind speed,wind direction,rainfall measurement and collection.In the raindrop spectrum sensor proposed in this paper,an isometric conductive ring probe is designed based on the electromigration effect of conductive ions in rainwater.The output voltage of the probe at different raindrop diameters is obtained by using an analog-to-digital converter and a peripheral resistor.Multiple sets of data were obtained through experiments,and the neural network training was used to obtain the relationship between the diameter of the raindrop and the output voltage of the sensor in order to achieve the measurement of the diameter of the raindrop.Experiments show that if the wind speed and the speed of the raindrop are not taken into account,the accuracy of the raindrop diameter sensor can be less than ±0.1 mm.In order to facilitate the later cross-platform development,this paper designs a kind of automatic weather station PC software basen on Qt,which is rich in base class and easy to program.It can realize real-time display,storage and remote access to measurement results.