The basic principle of the sensor is to convert the specific measured signal into a certain "usable signal" according to a certain rule through the sensitive element and the conversion element and output it to meet the requirements of information transmission, processing, recording, display and control.

Sensor principle

The basic principle of the sensor is to convert the specific measured signal into a certain "usable signal" according to a certain rule through the sensitive element and the conversion element and output it to meet the requirements of information transmission, processing, recording, display and control. Sensors can sense physical quantities such as force, temperature, light, sound, chemical composition, etc., and can convert them into electrical quantities such as voltage and current according to certain rules, or convert them into on-off circuits, which are generally composed of sensitive elements and conversion elements.

sensor application

1. Household appliances

Sensors are widely used in modern household appliances. Sensors are widely used in electronic stoves, automatic rice cookers, vacuum cleaners, air conditioners, electronic water heaters, hot air heaters, air dryers, alarms, electric fans, electric fans, game consoles, electronic mosquito repellents, washing machines, dishwashers, photo Cameras, refrigerators, color and flat-panel TVs, VCRs, tape recorders, radios, DVD players and home theaters have been widely used.

2. Medicine

With the development of medical electronics, the era of diagnosis based on the doctor's experience and feeling will be over. Now, with the application of medical sensors, it is possible to make difficult diagnoses on the surface and internal temperature of the human body, blood pressure and intracavitary pressure, blood and respiratory flow, tumors, blood analysis, pulse waves, heart sounds, and heart and brain waves. Obviously, sensors play a very important role in promoting the high development of medical technology.

3. Military field

Today's battlefields are all information-based battlefields, and informatization is absolutely inseparable from sensors. It can be said that it is used all the time and everywhere, ranging from equipment systems such as stars, bombs, aircraft, ships, tanks, artillery, etc., to individual combat weapons; from weapon systems participating in the war to logistical support; from military scientific experiments to Military equipment engineering; from battlefield operations to strategic and tactical command; from war preparation, strategic decision-making to war implementation, throughout the entire combat system and the entire process of war, and will definitely promote the time domain and airspace of operations in future high-tech wars And the frequency domain is further expanded, which affects and changes the way and efficiency of combat, and greatly improves the power of weapons and the ability of combat command and battlefield management.

4. Environmental protection

At present, the earth's air pollution, water pollution and noise have seriously damaged the earth's ecological balance and the environment on which we live. This situation has attracted the attention of all countries in the world. In order to protect the environment, various environmental monitoring instruments made of sensors are playing an active role.

China's current environment has been greatly polluted, mainly due to the serious pollution caused by the development of industry. Waters such as the Yangtze River and the Yellow River have varying degrees of pollution; the air is not fresh, especially in places with industries, such as PM2.5 exceeding the standard; these are detected by sensors.

5. Internet of Things

The Internet of Things refers to ubiquitous end devices (Devices) and facilities (Facilities), including sensors with "intrinsic intelligence", mobile terminals, industrial systems, building control systems, home smart facilities, video surveillance systems etc. and "External Enabled" (Enabled), such as various assets (Assets) affixed with RFID, individuals and vehicles carrying wireless terminals, "intelligent objects or animals" or "smart dust" (Mote), through Various wireless/wired long-distance/short-distance communication networks realize interconnection (M2M), application grand integration (Grand Integration), and cloud computing-based SaaS operation modes, providing safe, controllable and even personalized real-time online monitoring, Management and service functions such as positioning traceability, alarm linkage, dispatching command, contingency plan management, remote control, security protection, remote maintenance, online upgrade, statistical report, decision support, leadership desktop (Cockpit Dashboard for centralized display), etc., to realize "everything "The integration of "management, control and operation" of "high efficiency, energy saving, safety and environmental protection". To put it simply, the Internet of Things is the information transmission and control between things and things, people and things. There are three key technologies in the application of the Internet of Things, including sensor technology.

6. Robot

At present, in places with high labor intensity or dangerous operations, robots have been gradually used to replace human work. It is also very suitable for some high-speed and high-precision work to be undertaken by robots. However, most of these robots are used for processing, assembly, inspection, etc., and are not used for automatic mechanical single-function robots for production. Only sensors that detect the position and angle of the arm are used on these robots.

In order to make the functions of robots and humans closer, in order to engage in more advanced work, the robot is required to have the ability to judge. This requires the robot to be equipped with object detection sensors, especially vision sensors and tactile sensors, so that the robot can detect objects through vision. Perform recognition and detection, and produce pressure, force, sliding, and weight sensations on objects through the sense of touch. This type of robot is called an intelligent robot. It can not only engage in special operations, but also general production, affairs and housework can all be handled by intelligent robots. This is one of the main research objects for the development of robots.

7. Remote sensing technology

Satellite remote sensing (satellite remote sensing) is an integral part of space remote sensing, using artificial earth satellites as remote sensing platforms, mainly using satellites to conduct optical and electronic observations of the earth and the lower atmosphere. That is, from different working platforms far away from the ground (such as towers, balloons, airplanes, rockets, artificial earth satellites, spacecraft, space shuttles, etc.) through sensors, the electromagnetic wave (radiation) information on the earth's surface is detected, and the Transmission, processing and interpretation analysis, comprehensive technology for detection and monitoring of the earth's resources and environment.

8. The sensors used on aircraft and aerospace vehicles are near ultraviolet, visible light, far infrared and microwave sensors. Ultrasonic sensors are often used for underwater observation on ships. For example, to detect where some mineral resources are buried, you can use the infrared receiving sensor on the artificial satellite to measure the amount of infrared light emitted from the ground, and then the artificial satellite sends it to the ground station through microwaves, and the ground station computer processes it. The area where mineral deposits are buried can be judged according to the difference in the distribution of infrared rays.