Sensors are devices that perform input functions in a system as they sense the changes in a quantity. In simple terms, a sensor is a device that detects changes and events in a physical stimulus and provides a corresponding output signal that can be measured or recorded. The best example of a sensor is a mercury thermometer. Here the quantity that is being measured is heat or temperature. The measured temperature is converted to a readable value on the calibrated glass tube based on the expansion and contraction of liquid mercury.
What is a Transducer?
“Transducer” is a device that converts one form of energy into another with the help of an actuator. Generally, in the case of transducers, the power is in the form of a signal. A transducer is a term collectively used for both sensors and actuators. Actuators are devices that work opposite sensors. A sensor converts a physical event into an electrical signal, whereas an actuator converts an electrical signal into a physical event. When sensors are used at the system’s input, actuators perform output functions in a system as they control an external device.
Types of Sensors and Transducer
The different sensors and transducers available depend on what quantities they must measure. Transducers are available in various forms, from simple sensors to sophisticated, multi-function devices.
Some of the types based on stimuli of sensors are.
- Acoustic Sensors: Acoustic sensors can detect waves, wave velocity, and spectrum.
- Electric: They can detect an electric field, current, charge, potential, permittivity, and conductivity.
- Magnetic Sensors: Magnetic sensors detect permeability, magnetic field, and magnetic flux.
- Thermal Sensors: Thermal sensors detect temperature, specific heat, and thermal conductivity.
- Mechanical: Able to detect force, pressure, stress, strain, momentum, torque, Position, acceleration, shape, orientation, roughness, stiffness, etc.
- Optical: Wave, wave velocity, refractive index, reflectivity, absorption, and emissivity.
Applications and Most-used Sensors and Transducers
Some of the most used of these devices for different stimuli are;
- The input devices or sensors are photodiodes, phototransistors, light-dependent resistors, and solar cells for sensing light. The output devices or actuators are LEDs, displays, lamps, and fiber optics.
- The sensors are thermistors, thermocouples, resistance temperature detectors, and thermostats for sensing temperature.
- For sensing position, the input devices are the potentiometer, proximity sensor, and differential transformer. The output devices are the motor and panel meter.
- For sensing pressure, the sensors are strain gauge and load cell.
- The input devices are microphones for sensing sound, and the output devices are loudspeakers and buzzers.
- For sensing speed, the sensors used are tacho-generator and Doppler Effect sensors.
Furthermore, the basic requirements of a sensor include range, accuracy, sensitivity, stability, repeatability, response time, linearity, and ruggedness.
Conclusion
Sensors and transducers can also measure sound energy and provide an output signal, usually an electrical quantity. These two devices can be used in conjunction to measure the same physical phenomena. You can find these devices online by visiting our company Enrgtech for fine-quality and classic varieties at very affordable prices at a single click.
