From different angles, different sensor classification methods are formed. A measurement can be measured by different types of sensors, and the same principle can usually be measured. Therefore, the classification methods of sensors are different, and there is no unified classification method.
1. According to the working mechanism of the sensor
According to the scientific properties of the basic effect on which the perception is measured (external information), the sensors can be divided into three categories: physical sensors, chemical sensors and biosensors.
Physical sensor is a sensor that uses the physical properties of some components and the special physical properties of some functional materials, such as piezoelectric effect, magnetostrictive phenomenon, ion, thermoelectric, photoelectric, magnetoelectric and other effects, to transform the measured physical quantity into energy form signals that are easy to process. The small changes of the measured signals are converted into electrical signals, of which are the conductive ones, which is less difficult for subsequent development.
In the physical sensor can be divided into physical sensor and structural sensor. Structural sensor is based on the law of physics field, including the law of motion of the dynamic field, the electromagnetic law of the electromagnetic field. The characteristic of this kind of sensor is that the working principle of the sensor is based on the change of the field caused by the relative position of the element in the sensor, rather than based on the change of material characteristics. For example, the capacitive sensor is a structural sensor made of the electrostatic field law. The change of the shape and distance of the plate can change the performance of the capacitive sensor. Physical sensors are based on the laws of matter, such as Hook’s law, Ohm’s law, etc. The law of matter is a law of an objective property of matter. Most of this rule is given in the form of constants of the matter itself, the size of which determines the main performance of the sensor. Therefore, the performance of physical sensors varies with the material. For example, the piezoelectric sensor is a physical sensor made of the piezoelectric effect of materials, different piezoelectric materials, its piezoelectric effect is different.
Chemical sensors mainly use the principle of electrochemical reaction between sensitive materials and substances to convert the concentration of inorganic and organic chemical components into electrical signals, such as gas sensor, humidity sensor and ion sensor, among which the conductive role is ions. There are many kinds of ions, so the chemical sensor changes very much, which is more complex, and it is more difficult to the subsequent development.
Biosensors are sensors that use the ability of bioactive substances, such as molecules, cells, and even some biological tissues, to select the properties of certain substances, such as glucose and microelectrodes, glucose sensors, enzymes, microbial sensors, tissue sensors, and immune sensors. The research history of biosensor is short, but the development is very rapid. With the development of semiconductor technology, microelectronics technology and biotechnology, its performance will be further improved, multi-functional, integrated and intelligent biosensor will become a reality, the prospect is very broad.
2. According to the working principle of the sensor
According to the principle of sensor on signal conversion, it can be divided into resistive sensor, inductive sensor, capacitive sensor, piezoelectric sensor, magnetoelectric sensor, photoelectric sensor, thermoelectric sensor, wave sensor and so on. Classified according to the working principle, it is beneficial to understand the working principle of the sensor.
3. Classification by input information (being measured)
Sensors are classified according to the transmission volume (purpose), including displacement sensor, pressure sensor, position sensor, liquid level sensor energy consumption sensor, speed sensor, temperature sensor, vibration sensor, wet sensitive sensor, magnetic sensitive sensor, gas sensitive sensor, vacuum sensor, etc. The method of classification by measurement reflects the function and use of the sensor, which is conducive to the user to select the sensor specifically. In many cases, it will be classified according to the working principle and the classification of the measurement, such as strain pressure sensor, piezoelectric acceleration sensor, photoelectric disk speed sensor, etc.
4. Classification by application scope
According to the different application scope of sensors, usually divided into industrial, civil, scientific, medical, military sensors and so on. According to the specific use of occasions, it can also be divided into automotive, ships, aerospace sensors, etc. If according to the purpose of use, it can also be divided into measurement, monitoring, inspection, control, analytical sensors and so on.
www.bnsense.com