Types of Sensors Used in Modern Agriculture

Temperature Sensor

There are many types of temperature sensors, including thermocouple sensors using the thermoelectric effect, metal thermal resistance sensors and semiconductor thermistor sensors using the thermal resistance effect, transistor PN junction temperature sensors, integrated temperature sensors, and optical fiber temperature sensors developed in recent years, etc. , using these sensors, timely measurement of temperature can be implemented.

Humidity sensor

The humidity sensor can sense the atmospheric humidity and convert it into an appropriate electrical signal. According to different sensor principles, commonly used humidity sensors are divided into sintered semiconductor ceramic humidity sensors, porous oxide humidity sensors, junction and MOS humidity sensors, lithium chloride humidity sensors, and hydroxyethyl cellulose carbon humidity sensors. Sensors and polymer electrolyte humidity sensors, etc.

Gas sensor

Gas sensors can detect specific components in gas (mostly air) and convert them into corresponding electrical signals for output. Gas sensors can be divided into semiconductor gas sensors, solid electrolyte gas sensors, and concentration cell type gas sensors. There are many types of gas sensors such as sensors and combined potentiometer type gas sensors, among which the most commonly used are semiconductor gas sensors.

pH sensor

The pH sensor works according to the potentiometric method in electrochemistry and can be used to measure the acidity and alkalinity of the solution online. It generally consists of a measuring electrode and a reference electrode. The measuring electrode generally adopts glass electrode, and the reference electrode has two kinds: calomel electrode and silver-silver chloride electrode.

photoelectric sensor

There are also many types of photoelectric sensors, including photocells and photomultiplier tubes that use the external photoelectric effect, semiconductor photoresistors that use the photoconductive effect, photodiodes, phototransistors and photocells that use the photovoltaic effect, and optical fiber sensors that use total reflection of light. And CCD sensors (also known as charge-coupled devices) developed on the basis of MOS integrated circuit technology.

Pressure Sensor

There are many sensors that can measure pressure, such as strain resistance sensors made according to the resistance strain effect, piezoresistive sensors made according to the piezoresistive effect, piezoelectric sensors made according to the piezoelectric effect, and inductive and capacitive sensors. The pressure of the medium can be measured.

biological sensor

Biosensors are widely used in clinical diagnosis, industrial control, food and drug analysis, environmental protection, modern agriculture, and research in biotechnology and biochips in the national economy. Biosensors can be divided into five categories according to their molecular recognition elements (i.e., sensitive elements): enzyme sensors, microbial sensors, cell sensors, tissue sensors and immune sensors.