working principle of the ultrasonic wind speed sensor is to use the ultrasonic time difference method to measure the wind speed. Because of the speed of sound in the air, it will be superimposed with the speed of the airflow in the wind direction. If the ultrasonic wave travels in the same direction as the wind, its speed will increase;

The velocity of airflow measured by a thermal air speed sensor is a function of current and resistance. By keeping the current (or resistance) constant, the measured airflow speed corresponds only to the resistance (or current).

wind speed sensor is a very common type of wind speed sensor, the sensing part of which consists of three or four conical or hemispherical empty cups. The hollow cups are fixed on trigonal star-shaped brackets at 120° to each other or on cross-shaped brackets at 90° to each other, with the concave surfaces of the cups aligned in one direction and the entire cross-arm frame fixed on a vertical ax···

Soil temperature and humidity meters are used to control the temperature and humidity of the target soil in real time in order to better assist farmers in their farming activities and to control the soil temperature and humidity within the appropriate range for plant growth, helping to produce quality and quantity.

The soil moisture meter is also called Mobile Handheld Soil Moisture Monitor. The instrument can detect two parameters of soil moisture and soil temperature. Because the instrument is small and easy to carry, agricultural technicians can take it to the field at any time.

By embedding IoT sensors in agricultural soils, farmers can monitor soil moisture content and understand its chemical composition in real-time around the clock. These devices can automatically notify farmers when soil moisture or nitrogen, potassium, phosphorus, sulfur and other elements reach unsatisfactory values.

Smart agriculture or IoT agriculture involves 6 system solutions including video surveillance system, intelligent greenhouse environment monitoring system, picking control system, processing control system, traceability system, acquisition, circulation control and sales control system.

The smart agricultural greenhouse monitoring system can wirelessly collect and transmit the temperature, humidity, light, soil temperature, soil humidity, CO2 concentration, leaf humidity, dew point temperature and other environmental parameters in the greenhouse in real time.

A sensor that outputs a digital quantity is a digital sensor.A sensor that outputs an analog quantity is an analog sensor.

There are errors in the daily maintenance and management of the soil moisture sensor. Many problems are mostly caused by improper installation, the failure of the instrument itself, and inadequate maintenance and management. Therefore, the daily maintenance of the observation instrument should be strengthened, and problems should be found and solved in time to ensure that the soil moisture is auto···