Examples of application of various sensors, the application of sensors is very common in our lives, there are relatively many types of sensors, and the application scope is relatively light. Different sensors have different functions. Application examples of various sensors are as follows.
Application examples of various sensors 1 1. Definition of sensors
A device or equipment that can sense a specified measured signal and convert it into a usable signal according to a certain law (mathematical function law), usually a device consisting of a sensitive element and a conversion element, that is, a sensor. Sensors convert physical parameters (such as temperature, blood pressure, humidity, speed, etc. ) into a signal that can be measured by electricity. We can explain the example of temperature first. Mercury in a glass thermometer expands and contracts the liquid, thus converting the measured temperature into a temperature that an observer can read on a calibrated glass tube.
Second, the principle of sensor selection
When selecting a sensor, certain characteristics must be considered, as follows:
1, accuracy-the accuracy of the sensor only needs to meet the accuracy requirements of the whole measurement system, not too high. Usually the higher the accuracy, the more expensive it is.
2. Linear range-the range in which the input is proportional to the output.
3. Measuring environment-there are usually requirements for temperature/humidity.
4. Calibration-It is very important for most measuring equipment, because the reading will change with time.
5. Stability-The ability of a sensor to keep its performance unchanged after a period of use is called stability.
Three, the main classification of sensors
Sensors are divided into the following standards:
1, the main input (measured person), also called by use, is divided into pressure sensor and force sensor, position sensor, liquid level sensor, energy consumption sensor, speed sensor, acceleration sensor, radiation sensor, thermal sensor, etc.
2. Measurement purpose (by physical and chemical action)
The physical sensor is made by using the characteristics that some physical properties of the measured substance have changed obviously. Chemical sensors are composed of sensitive elements, which can convert chemical quantities such as composition and concentration of chemical substances into electrical quantities. Biosensor is a sensor that uses the characteristics of various organisms or biological substances to detect and identify chemical components in organisms.
3. Manufacturing process
4, according to the principle
Vibration sensor, humidity sensor, magnetic sensor, gas sensor, vacuum sensor, biosensor, etc.
5. Output signal
Analog sensor: converts the measured non-electric quantity into analog electric signal.
Digital sensor: converts the measured non-electric quantity into digital output signal (including direct conversion and indirect conversion).
Pseudo-digital sensor: the output (including direct or indirect conversion) that converts the measured signal into a frequency signal or a short-period signal.
Switch sensor: When the measured signal reaches a certain threshold, the sensor outputs a set low-level or high-level signal accordingly.
Four or five commonly used sensors
Some common sensors, their principles and applications are described as follows:
(1) temperature sensor
This device collects information about temperature from the source and converts it into a form that other devices or people can understand. The best example of a temperature sensor is a glass mercury thermometer, which will expand and contract with the change of temperature. The outside temperature is the source of temperature measurement, and the observer observes the position of mercury to measure the temperature. There are two basic types of temperature sensors:
Contact sensor-This type of sensor needs direct physical contact with the sensed object or medium. Such as a thermometer.
Non-contact sensor-This type of sensor does not need any physical contact with the detected object or medium. They monitor non-reflective solids and liquids, but they are useless to gases because of their natural transparency. These sensors use Planck's law to measure temperature. This law deals with the heat radiated from a heat source to measure the temperature.
Working principle and examples of different types of temperature sensors
(i) Thermocouples-They consist of two wires (each made of different homogeneous alloys or metals), one end of which is connected to form a measuring joint, which leads to the measured element. The other end of the wire is connected to the measuring device, where a reference contact is formed. Because the temperatures of the two nodes are different, current flows through the circuit, and the measured millivolts are used to determine the temperature of the nodes.
(2) Resistance Temperature Detector (RTD)-This is a kind of thermal resistance, which is made to change the resistance with the change of temperature. They are more expensive than any other temperature detection equipment.
(iii) Thermistor-this is another kind of resistance, and the large change of resistance is directly proportional to the small change of temperature.
(2) Infrared sensor
The device emits or detects infrared radiation to sense a specific stage in the environment. Generally speaking, all objects in the infrared spectrum will emit thermal radiation, and infrared sensors will detect this invisible radiation.
(3) ultraviolet sensor
These sensors measure the intensity or power of incident ultraviolet rays. The wavelength of this electromagnetic radiation is longer than X-ray, but still shorter than visible light. An active material called polycrystalline diamond is being used for reliable ultraviolet transmission, and ultraviolet sensors can find the environment exposed to ultraviolet radiation.
(4) Touch sensor
The touch sensor acts as a variable resistor according to the touch position. The touch sensor consists of the following components: fully conductive materials, such as copper, insulating and isolating materials, such as foam or plastic, and partially conductive materials.
(5) Proximity sensor
Proximity sensors can detect the existence of objects almost without contact points. Because there is no contact between the sensor and the measured object and there are no mechanical parts, these sensors have long service life and high reliability. Different types of proximity sensors include inductive proximity sensors, capacitive proximity sensors, ultrasonic proximity sensors, photoelectric sensors, Hall effect sensors and so on.
Verb (abbreviation for verb) advanced sensor technology
Sensor technology is widely used in manufacturing industry. Advanced technologies are as follows:
First, bar code identification-all products sold in the market have a universal product code (UPC), which is a 12-digit code. Five of them represent manufacturers and the other five represent products. The first six bits are coded as bright bars and dark bars. The first number indicates the type of digital system, and the second number indicates the parity and the accuracy of reading. The remaining six digits are represented by dark lines and dark lines, which are in the opposite order to the first six digits. The barcode is shown in the figure below.
Bar code readers can manage different bar code standards even if they don't know the standard code. The disadvantage of barcode is that if the barcode is covered with grease or dust, the barcode scanner will not be able to read it.
Second, the transponder-in the automobile part, radio frequency equipment is used in many cases. The transponder is hidden in the plastic head of the key and no one can see it. Insert the key into the ignition lock cylinder. When you turn the key, the computer will send a radio signal to the radio transceiver. The computer will not ignite the engine until the transponder responds to the signal. These transponders are driven by radio signals.
Third, electromagnetic identification of manufacturing parts-this is similar to bar code technology, and data can be encoded on magnetic strips. Using magnetic stripe technology, data can be read even if the code is hidden in grease or dust.
Fourth, surface acoustic waves-this process is similar to radio frequency identification. Here, the component identification is triggered by the radar type signal, which is transmitted over a long distance compared with the RF system.
5. Optical Character Recognition-This is an automatic recognition technology that uses alphanumeric characters as information sources. In the United States, mail processing centers use optical character recognition. They are also used in vision systems and speech recognition systems.
Compared with the booming MRO e-commerce platform in China, WKEA Jia Wei Industrial Products has been deeply involved in the industrial products industry for 25 years, providing customers with the best service and the most appropriate price, which not only ensures the quality, but also makes customers feel "assured when buying, assured when using".
Examples of application of various sensors 2 Seven applications of sensors in our life.
Sensor is a kind of detection device that can sense the measured information, and can convert the sensed information into electrical signals or other required forms of information output according to certain rules to meet the requirements of information transmission, processing, storage, display, recording and control. This is the first step to realize automatic detection and automatic control.
In a narrow sense, a sensor is defined as a device or device that can convert external non-electric information into electrical signals for output. The broad definition of sensor: "Any device or equipment that uses certain laws, theorems, laws and effects of substances (physics, chemistry and biology) to convert energy and information, and the output and input are in strict one-to-one correspondence, can be called a sensor".
In the information-based 2 1 century, sensors are essential, and their applications are very wide, such as computers, production automation, modern information, * *, transportation, chemistry, environmental protection, energy, marine development, remote sensing, aerospace and so on. Here are some commonly used sensors.
1, sensors and environmental protection
At present, the air pollution, water pollution and noise of the earth have seriously damaged the ecological balance of the earth and the environment on which we live, which 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.
The environment in China has been seriously polluted, which is mainly due to the development of industry. The waters such as the Yangtze River and the Yellow River are polluted to varying degrees. Now the air is not fresh, especially in industrial places, such as PM2,5, which exceeds the standard; These are all detected by sensors.
2. Application of sensors in robots
At present, robots have been gradually used to replace human work in places with high labor intensity or dangerous operations. It is also very suitable for robots to undertake some high-speed and high-precision work. However, most of these robots are automatic mechanical single-energy robots, which are used for processing, assembly, inspection and other work. These robots only use sensors to detect the position and angle of the arm.
In order to make the functions of robots and people closer, and to engage in more demanding work, robots are required to have judgment ability. This requires the robot to be equipped with sensors for physical examination, especially visual sensors and tactile sensors, so that the robot can identify and detect objects through vision, and generate pressure, force, sliding and weight sense on objects through touch. This kind of robot is called intelligent robot, which can not only engage in special operations, but also handle general production, affairs and housework. It is one of the main research objects of developing robots now.
3. Sensors and household appliances
Sensors are widely used in modern household appliances. Sensors are widely used in electric furnaces, automatic rice cookers, vacuum cleaners, air conditioners, electronic water heaters, hot air heaters, air dryers, alarms, electric fans, game machines, electronic mosquito repellent, washing machines, dishwashers, cameras, refrigerators, color and flat-panel TVs, video recorders, radios, DVD players and home theaters.
With the continuous improvement of people's living standards, there is a strong demand for improving the function and automation of household appliances. In order to meet these requirements, first of all, we should use high-precision sensors that can detect analog signals to obtain correct control information, and then control it by microcomputer. Using household appliances is more convenient, safe and reliable, reducing energy consumption and creating a comfortable living environment for more families.
The blueprint of home automation is being designed at present. In the future, the microcomputer of the central control device will monitor the state of the home through various sensors instead of people, and carry out various controls through control equipment. The main contents of home automation include: safety monitoring and alarm, air conditioning and lighting control, energy consumption control, sunlight automatic tracking, housework automation and personal health management. The realization of home automation can make people have more time for study, education or rest and entertainment.
4. Sensors and the Internet of Things
The Internet of Things is a network based on information carriers such as the Internet and traditional telecommunication networks, which enables all ordinary physical objects that can be independently addressed to be interconnected. It has three important characteristics: public object equipment, autonomous terminal interconnection and universal service intelligence.
Internet of Things refers to ubiquitous terminal equipment and facilities, including sensors with "intrinsic intelligence", mobile terminals, industrial systems, building control systems, dust intelligent facilities, video monitoring systems and so on. And "externally enabled", such as various assets tagged with RFID.
Through various wireless/wired long/short-distance communication networks, we can realize cloud computing-based interconnection (M2M), big convergence, SaaS operation and other modes, and provide safe, controllable and even personalized real-time online monitoring, position tracking, alarm linkage, dispatch and command, plan management, remote control, security prevention, remote maintenance, online upgrade, statistical reports, decision support and leadership desktop (COC with centralized display).
Realize the integration of "management, control and operation" of "everything" with high efficiency, energy saving, safety and environmental protection. Simply put, the Internet of Things is the information transmission and control between people. There are three key technologies in the application of Internet of Things, including sensor technology.
5. Application of sensors in medical and human medicine.
With the development of medical electronics, the era of relying on doctors' experience and feelings for diagnosis will end. At present, medical sensors can be used to diagnose body surface and internal temperature, blood pressure and intraluminal pressure, blood and respiratory flow, tumor, blood analysis, pulse wave and heart sound, cardiac brain waves and so on. Obviously, sensors play a very important role in promoting the high development of medical technology.
In order to improve people's health and waste level, the reform of medical system in China has expanded the medical service target to the whole people. In the past, medical work was only centered on * * *. In the future, medical work will play a role in early diagnosis, early diagnosis, remote diagnosis and artificial organ development, and sensors will be used more and more in these areas.
6. Sensors and remote sensing technology
Satellite remote sensing is an integral part of space remote sensing. With artificial earth satellite as the remote sensing platform, satellites are mainly used for optical and electronic observation of the earth and the lower atmosphere. That is, the electromagnetic wave (radiation) information on the earth's surface is detected by sensors on different working platforms far away from the ground (such as towers, balloons, airplanes, rockets, artificial earth satellites, spacecraft, space shuttles, etc.). ) and transmit, process, interpret and analyze the information to detect and monitor the resources and environment of the earth.
Sensors used in aircraft and spacecraft include near ultraviolet, visible light, far infrared and microwave sensors. Ultrasonic sensors are often used when observing underwater on board. For example, to detect where some mineral resources are buried, we can measure the amount of infrared emitted by the ground through the infrared receiving sensor on the satellite, and then send it to the ground station by microwave. After the computer processing of the ground station, we can judge the buried area of mineral resources according to the difference of infrared distribution.
7. The application of sensors in * *
The current battlefields are all information battlefields, and information cannot be separated from sensors. Experts believe that the level of sensor manufacturing technology in a country determines the level of weapon manufacturing and weapon automation, and ultimately determines the quality of weapon performance.
At present, sensors are widely used in * *, which can be said to be ubiquitous, ranging from equipment systems such as stars, two bombs, airplanes, ships, tanks and artillery to individual combat weapons; From weapon system to logistics support; From scientific experiments to equipment engineering;
From battlefield operations to strategic and tactical command; From war preparation, strategic decision-making to war implementation, it permeates the whole combat system and the whole process of war, which will certainly promote the expansion of time domain, space domain and frequency domain of future high-tech wars, influence and change the mode and efficiency of operations, and greatly improve the power of weapons and the ability of operational command and battlefield management.
From the above, we can see that sensors are widely used in our lives, which can be said to be everywhere.
Application Example of Various Sensors 3 Detection Methods of Sensors
There are three detection methods of sensors: direct detection, indirect detection and combined detection. Direct detection Direct detection means that when a sensing instrument is used for detection, the reading of the instrument can directly indicate the required result without any operation. For example, using a magnetoelectric ammeter to detect the current of the circuit and using a spring tube pressure gauge to detect the pressure of the boiler are all direct detection.
The advantage of direct detection is that the detection process is simple and fast, but the disadvantage is that the detection accuracy is not easy to reach very high. This detection method is widely used in engineering.
Indirect detection in some detection occasions, it is impossible or inconvenient to directly detect the detected object, so it is difficult to insist on detecting several quantities that have a certain functional relationship with the measured physical quantity first, and then substituting the detected values into the cluster number relationship, and obtaining the required results through calculation. This method is called indirect detection. Indirect detection requires more detection than direct detection, the calculation process is more complicated, and there are many factors leading to crop failure.
However, if the error is analyzed and the optimized detection method is selected and determined, indirect detection can be carried out under ideal conditions. The accuracy of detection results is not necessarily low, and sometimes higher detection accuracy can be obtained-indirect detection is generally used in situations where direct detection is inconvenient or indirect detection means are lacking.
When the sensor instrument is used for joint detection, if the measured physical quantity must be solved by simultaneous equations, the final result can be obtained. This kind of detection is called joint detection. In the process of joint detection, it is generally necessary to change the test conditions to obtain the data needed for a set of simultaneous equations.
Joint detection is a special precision detection method, which has complex operation procedures and takes a long time, and is generally suitable for scientific experiments or special occasions. The quick sealing joint is the sealed quick joint of Haiyipu Machinery, which can make the test connection easier, faster and safer.