With the rapid development of electronic technology, many electronic devices around us operate without human touch, and sensors play an integral role in this regard, just like human perception. Sensor The sensor is a detection device that can feel the measured information and transform the felt information into an electrical signal or other required form of information output according to a certain law to meet the requirements of information transmission, processing, storage, display, recording and control. The existence and development of sensors allow objects to have senses such as touch, taste and smell, making objects come alive, and sensors can be regarded as an extension of human five senses. The main function of the sensor is to identify and communicate physical quantities such as temperature, heat, pressure, distance, humidity, gas, etc. You can easily understand this with this simplified block diagram below. 
Different types of sensors have specific roles in everyday life applications, commercial and industrial equipment, and educational projects. Today we're going to take a look at what are the different types of sensors1. Temperature sensor
Temperature sensors are used to detect temperature and heat energy and convert them into electrical signals (in the form of voltage or current). The several types of temperature sensors in use are: thermometer, thermocouple, resistor temperature detector, thermistor temperature sensor, semiconductor temperature sensor, vibrating wire temperature sensor, temperature sensor for computers, refrigerators, automobiles, medical equipment, cooking appliances, electric motors, etc. 2. Pressure sensor
Pressure sensors are called pressure sensors or pressure transmitters or pressure gauges. The pressure sensor detects the pressure of air, gas, and water and provides an electrical signal to the controller. According to different uses and more functions, it is divided into different parts, such as: vacuum pressure sensor, absolute pressure sensor, gauge pressure sensor, differential pressure sensor, pressure sensor are mainly used in: booster cylinder, booster, gas-liquid booster cylinder, gas-liquid booster, press, compressor, air conditioning and refrigeration equipment and other fields. 3. Touch sensor
Touch sensors are also known as tactile sensors. It is a sensor used to measure the contact state of the surface of an object, including the change of contact state, it can be used to detect the touch between two or more objects, and can determine the relative position of the object, as well as the surface temperature, operating force and other parameters of the object. Capacitive touch sensors, resistive touch sensors are the best examples of touch sensors. Compared with traditional sensors, touch sensors have higher accuracy, sensitivity, detection range and detail description capabilities, and can complete the sensing function in a limited space. Touch sensors can detect changes such as temperature and pressure in the field in real time, providing accurate operational information. It can also be used to switch wake-up, security, gesture capture, and more. Touch sensors are widely used in industrial control, turning on and off light switches, air conditioning (AC) remote control, door opening and closing operations, elevators and robots, smartphones, etc. Oximeters are one of the best examples of touch-based sensors detecting a person's oxygen levels. 4. Image sensor
The image sensor uses the photoelectric conversion function of the optoelectronic device to convert the light image on the photosensitive surface into an electrical signal that is proportional to the light image. In general, there are two main types of electronic image sensors. Charge-Coupled Device (CCD)Active Pixel Sensor (CMOS)Image sensors are mainly used in digital cameras, closed-circuit television (CCTV), medical imaging equipment, thermal imaging equipment, radar, sonar, etc. 5. Motion sensorMotion sensors measure and record physical activity or movement. It is divided into different types. Active Motion Sensors: Passive Motion Sensors, Tomographic Motion Sensors, Gesture Motion Sensors, Motion Sensors are used in Home Security, Automatic Door Operation, Microwave, Robotics, Ultrasonic, Gesture Detectors, etc. 6. a light sensor
A light sensor is an optoelectronic device. This sensor detects the brightness or luminescence of light or photons and converts it into an electrical signal. There are three types of light sensors: photoresistors or light-correlated resistors (LDRs) photodiodes phototransistors which are widely used in solar energy systems, automobiles, the agricultural sector (sprinkler systems) and electron-based project equipment such as Arduino. 7. Vibration sensor
Sometimes, vibration sensors are referred to as piezoelectric sensors. Vibration sensors detect and record any movement or activity. It provides data or signals to connected machines or systems. If there is any hazardous activity, this sensor helps to send a confirmation. Vibration sensors are needed in industrial sectors such as gas and oil, food and beverage, mining, metalworking, papermaking, wind power, power generation, and more. 8. Humidity sensor
Moisture sensors are the simplest humidity sensors. There are two main types of moisture-sensitive components: resistive type and capacitive type. Humidity can be measured by coating the substrate with a film made of a moisture-sensitive material, and when water vapor from the air is adsorbed on the moisture-sensing film, the resistivity and resistance values of the component change. In industrial and agricultural production, meteorology, environmental protection, national defense, scientific research, aerospace and other departments, it is often necessary to measure and control environmental humidity. 9. a proximity sensor
Proximity sensors are a general term for sensors that replace contact detection methods such as limit switches and are designed to detect without touching the detection object. It can detect the movement and presence of objects and convert them into electrical signals. Among the detection methods that are replaced with electrical signals, there are methods that use the eddy current generated in the metal body of the detection object caused by electromagnetic induction, the method of changing the capacity of the electrical signal caused by the proximity of the measuring body, and the method of turning stones and guiding switches. Proximity sensors can easily detect nearby objects without any physical contact. It is divided into different types: Capacitive Proximity SensorInductive Proximity Sensor Proximity Sensor Proximity Sensor is widely used in smartphones, tablets, machines, robotic systems, roller coasters, etc. 10. Color sensor
The color sensor, also known as the color recognition sensor or color sensor, is a sensor that compares the color of the object with the reference color that has been taught before to detect the color, and when the two colors coincide within a certain error range, the detection result is output. Color sensors are a type of photoelectric sensor. Color sensors play an extremely important role in end devices, such as calibration devices for color monitorsColor printers and plotters;Coatings, textiles and cosmetics manufacturing, as well as medical applications such as blood diagnostics, urine sample analysis and dental orthopedics. 11. a radiation sensorA radiation sensor is an electronic instrument used to sense and measure radiation particles, neutrons, X-rays, etc. In addition, it can also sense electromagnetic radiation such as waves, cosmic radiation (sunlight). There are three different types of radiation sensors: gas-filled radiation sensors, scintillation radiation sensors, solid-state radiation sensors, which are used for nuclear energy, medical imaging modes, and environmental radioactivity monitoring. 12. a liquid level sensor
A liquid level sensor (hydrostatic level gauge, liquid level transmitter, liquid level sensor, water level sensor) is a pressure sensor that measures the liquid level. Based on the principle that the measured liquid static pressure is proportional to the height of the liquid, the static pressure of the measured liquid is converted into an electrical signal by using an isolated diffusion silicon sensitive element or a ceramic capacitive pressure sensitive sensor, and then converted into a standard electrical signal (generally 4 20mA 1 5VDC) after temperature compensation and linear correction. It is divided into different parts: laser liquid level sensor, float sensor, capacitive liquid level sensor, resistive liquid level sensor, ultrasonic liquid level sensor, hydrostatic liquid level sensor, optical liquid level sensor, electromagnetic liquid level sensor, suitable for petrochemical, metallurgy, electric power, pharmaceutical, water supply and drainage, environmental protection and other systems and industries of various media level measurement. 13. a position sensor
Position sensors that determine displacement and position (e.g., linear and rotational) are used to measure the position of the robot itself. Basically, there are several types of position sensors: Optical Position SensorsLinear Position SensorsRotary Position SensorsInductive Position SensorsCapacitive Position SensorsCapacitive Position SensorsFiber Optic Position SensorUltrasonic Position SensorsFor example, a potentiometer contains a rotary position sensor that can vary with angular motion. Position sensors are used in domestic and industrial applications such as door closure opening, valve monitoring, motor control, throttle valves to control the flow of fuel or power to the engine. 14. a gas sensor
A gas sensor is a converter that converts the volume fraction of a gas into a corresponding electrical signal. It is used to detect different types of gases, toxic or ** gases, smoke in the air. Some of these sensors are also capable of measuring gas concentrations. Gas sensors can be divided into: semiconductor gas sensors, electrochemical gas sensors, catalytic combustion gas sensors, thermal conductivity gas sensors, infrared gas sensors, solid electrolyte gas sensors, gas sensors have a wide range of applications, such as coal, petrochemical, gasoline stations, smart homes, automotive electronics, industrial processes, environmental monitoring, consumer electronics and other industries. 15. a flame sensor
A flame detector is a sensor that the robot uses to search for the source of fire. Flame sensors make it easy to detect fires or flames in nearby materials. These detected signals are passed on to the connected control device. It is used in alarm systems, natural gas plants, fire extinguishing systems, and fire detector projects based on Arduino-based designs in the industrial sector. 16. Liquid leakage sensor
Liquid leakage sensors are used in closed containers or vacuums to detect water leaks, fluid leaks, air leaks, etc. Depending on the job role, it is divided into two main parts: Dispense Liquid Leak Sensors, Flow Liquid Leak Sensors17. an accelerometer
An accelerometer is an instrument that measures the acceleration or velocity of motion. An accelerometer consists of a sensing mass (also known as a sensitive mass), a support, a potentiometer, a spring, a damper, and a housing. It is used in many applications such as gesture-controlled robots, aircraft and missile navigation systems, process and control systems, vehicle acceleration, and other rotating electronics such as turbines, drums, fans, compressors, pumps. 18. an inclination sensor
The tilt sensor detects and changes with the angular motion, angular slope, angular motion, axis of the reference plane. It is mainly used to monitor angle and auto-rotation operations in mobile phones, tablets, handheld games, boats, vehicles, airplanes, etc. 19. marking the sensorMarker sensors are used as photoelectric sensors. It is used to sense color markings in the presence of an object. Marking sensors are widely used in the printing and packaging industries. 20. a float flow sensor
The metal tube float flow sensor is a kind of variable area flow measurement instrument commonly used in industrial automation process control. It has the characteristics of small size, large detection range and easy to use. Due to the variable area measuring principle, the metal tube float flow sensor is suitable for measuring liquids, gases;Therefore, it is widely used in major industrial fields such as petroleum, chemical industry, power generation, pharmaceutical, food, water treatment, etc.