Sensors
- [Stanford University]
- Overview
Sensors are very important to measurement science and technology. They are an essential part of new measurement techniques and instrumentation systems. The key qualities of a good sensor system are high resolution, high reliability, low cost, proper output for a given input (good sensitivity), fast response time, small random and small systematic errors in the results. Linearity is also useful, but with the advent of lookup tables and software, it's not as important as it used to be.
Over the past few years, the world has invested a lot of effort in a wide range of sensors ranging from nanoscale sensors to sensor networks. Collectively, these broad multidisciplinary efforts are developing an important technology roadmap for future sensors with new modalities, significantly enhanced effectiveness, and integrated functions (data processing, computation, decision making, and communication).
Properly organized, they will have important relevance to life sciences and safety applications such as sensing and monitoring of chemical, biological, radiological and explosive threats.
- Sensors
A sensor is a device that generates an output signal to sense a physical phenomenon.
In the broadest definition, a sensor is a device, module, machine, or subsystem that detects events or changes in the environment and sends the information to other electronic devices, usually a computer processor. Sensors are always used with other electronic devices.
Sensors are used in everyday objects such as touch-sensitive elevator buttons (tactile sensors) and lights that are dimmed or brightened by touching the base, as well as countless applications that most people never realize. Advances in micromechanics and easy-to-use microcontroller platforms have expanded the use of sensors beyond traditional temperature, pressure, and flow measurement, such as MARG sensors.
Analog sensors such as potentiometers and force sensitive resistors are still widely used. Their applications include manufacturing and machinery, aircraft and aerospace, automotive, medicine, robotics, and many other aspects of our daily lives.
There are many other sensors that measure the chemical and physical properties of materials, including optical sensors for refractive index measurements, vibration sensors for fluid viscosity measurements, and electrochemical sensors for monitoring the pH of fluids.
- Different Types of Sensors
The following is a list of different types of sensors that are commonly used in various applications. All these sensors are used for measuring one of the physical properties like Temperature, Resistance, Capacitance, Conduction, Heat Transfer etc.
- Temperature Sensor
- Proximity Sensor
- Accelerometer
- IR Sensor (Infrared Sensor)
- Pressure Sensor
- Light Sensor
- Ultrasonic Sensor
- Smoke, Gas and Alcohol Sensor
- Touch Sensor
- Color Sensor
- Humidity Sensor
- Position Sensor
- Magnetic Sensor (Hall Effect Sensor)
- Microphone (Sound Sensor)
- Tilt Sensor
- Flow and Level Sensor
- PIR Sensor
- Touch Sensor
- Strain and Weight Sensor
- [Vienna, Austria]
- Sensors and Sensing Technology
Sensing technology uses sensors to detect and respond to changes in the physical environment. Sensors can measure various properties such as temperature, pressure, light, sound, and motion. They use this information to convert into a readable signal. There are a wide variety of sensors available for practically any industrial need.
Here are some examples of sensing technology:
- Optical sensors: Convert light rays into electrical signals. They are used in many devices, including smartphones, robotics, Blu-ray players, home security systems, and medical devices. Optical sensors are also used in heart rate monitors and breath analysis.
- Pressure sensors: Measure the pressure of a liquid or gas. They are used in machinery, automobiles, aircraft, HVAC systems, and other environments. Pressure sensors convert the pressure into an electrical signal, which can be variable voltage or current.
- Temperature sensors: Measure the amount of heat energy or temperature. A common type of temperature sensor is a thermocouple, which consists of two dissimilar metallic conductors joined together. Heat produces a voltage difference between the metals which can be measured.
- Image sensors: Allow users to see objects and locations remotely. They are used in robotic devices, drones, manufacturing, and security systems.
- Motion sensor technology: Uses infrared light or microwave radiation to sense a person's movement. It is often used for security purposes, but also has other applications, such as industrial process control and robotics.
- Proximity sensors: Detect the presence of nearby objects without any physical contact. They are commonly used in smartphones for touchless control and in automotive systems for parking assistance.
- Humidity sensor: Senses, measures, and reports both moisture and air temperature. The ratio of moisture in the air to the highest amount of moisture at a particular air temperature is called relative humidity.
- Ultrasonic sensor: A non-contact type device that can be used to measure distance as well as velocity of an object. It works based on the properties of the sound waves with frequency greater than that of the human audible range.
[More to come ...]
