What does the sensor principle mean?

What is the working principle of a temperature sensor? The principles of temperature sensors are broadly categorized as follows i. Thermal Expansion 1. Thermal Expansion 1. Thermal Expansion Sensors for Metals Metals produce a corresponding extension in response to a change in ambient temperature, so the sensor can signal this response in different ways. Example: Bimetal Sensor A bimetal consists of two pieces of metal with different coefficients of expansion that are bonded together. As the temperature changes, material A expands more than the other metal, causing the metal piece to bend. The curvature of the bending is converted into an output signal. This is the same principle used in dial-type room thermometers. Bimetallic Rod and Tube Sensors As the temperature increases, the length of the metal tube (material A) increases while the length of the non-expanding steel rod (metal B) does not, so that the linear expansion of the tube can be transmitted due to the change in position. In turn, this linear expansion can be converted into an output signal

Can someone explain to me how the sensor works?

When a voltage is applied to both ends of the coil to generate sufficient current, the magnetism increases and the contacts are attracted, so that the external circuit is closed or broken (depending on the initial state), thus controlling the external circuit.

Introducing - What is a sensor? Principle? Classification? Characteristics?

The problem you mention can't be fully learned in five years of undergraduate study at Tsinghua. I can only explain it briefly. (1) Sensor English is "Sensor" means feeling or perception, etc., the sensor common definition can be said to be "information pickup device or device" strict definition is: the measured value of the form (such as physical quantities, chemical quantities biomass, etc.). Transforms the measured quantity form (such as physical quantity, chemical quantity, biological quantity, etc.) into another kind of device or equipment which has a definite correspondence with it and is easy to measure the quantity form. (2) Broadly speaking, most sensors use the principle of conversion of the form of value. (3) According to the input quantity classification: displacement, pressure, temperature, speed and other sensors, named after the measured physical quantity. Classification by operating principle: thermoelectric, piezoelectric, strain ...... Classification by physical phenomenon: structure, physical properties ...... Classification by energy relationship: ...... Classification by output signal: ...... 4) The characteristic is to replace the human ear, eye, nose and other organs to perceive and obtain the information and information in the natural world that people can't obtain directly. (5) Used in the development of human science, transformation of nature, production, life and other human beings involved in all areas. (6) The market has: smoke, temperature, magnetic, dry humidity, sense the movement of objects, pyro-infrared, microwave Doppler, wired, wireless

What is the principle of pressure sensors? What are the main applications?

The piezoelectric effect is the main operating principle of piezoelectric sensors. Piezoelectric sensors cannot be used for static measurements because the charge after an external force is only preserved if the loop has an infinitely large input impedance. This is not the case in practice, so this determines that piezoelectric sensors are only capable of measuring dynamic stresses.　　Piezoelectric sensors are mainly used in the measurement of acceleration, pressure and force. Piezoelectric acceleration sensor is a commonly used accelerometer. It has excellent features such as simple structure, small size, light weight and long service life. Piezoelectric acceleration sensors have been widely used in vibration and shock measurements in airplanes, automobiles, ships, bridges and buildings, especially in aviation and astronautics where they have a special place. Piezoelectric sensors can also be used to measure combustion pressure measurements and vacuum measurements inside engines. It can also be used in the military industry, for example, it is used to measure the instantaneous change in the chamber pressure of the gun bullet in the chamber and the muzzle of the shock wave pressure. It can be used to measure both large and small pressures.

What is the working principle of the photoelectric sensor and which one is good at it?

A photoelectric sensor is a device that converts light signals into electrical signals to detect a target through the use of optoelectronics.　The physical principle of the photoelectric sensor is based on the photoelectric effect, that is, according to the electrical characteristics (irradiated by light and thus change). Currently in the country, high visibility, do a better job is Yipu.