There are different Types of sensors Used to translate the information that comes from outside in an electrical impulse. This impulse usually passes to a control unit where it is analyzed and transformed with the aim of generating a reaction or response.
The information that arrives from the outside to any sensor is a physical or chemical stimulus that, internally, is translated in an electrical magnitude.
Light sensor
Sensors emulate the sensory system of humans Thus, different machines use sensors to interact with the environment that surrounds them (Porto & Gardey, 2010).
A sensor is also used to obtain information about the environment. Thus, a thermometer is a sensor that provides numerical information about the temperature of a given environment.
Many times we use sensors to generate answers that facilitate the accomplishment of daily activities.
Sensors today are part of our daily lives. We are in permanent contact with different types of sensors that help to facilitate the tasks of the day to day.
In this way, automatic doorposts, solar panels, our smartphones, and other devices are equipped with sensors that help us to interact better with the environment (Agarwal, 2017).
Main Types of Sensors
There are multiple types of sensors whose function varies according to the type of stimulus they can detect (Garage, 2017).
Ultrasonic
They are sensors used to detect the physical proximity of an object in order to avoid friction or mechanical shock.
They operate by sending a sound wave, which then collides with a surface and is returned. In this way, the sensor measures the time it takes to return the wave and thus calculates the distance between objects.
It is a type of sensor that only works in spaces where there is presence of air, since the displacement of the sound wave can only occur in this medium.
On the other hand, it is useful for detecting objects regardless of their state (solid or liquid) or their color, so they are excellent for tracking or measuring distances (Sensors and Transducers, 2017).
Humidity
They are sensors that measure the relative humidity and the temperature of an environment. They have integrated circuits that allow them to emit a conditioned signal.
Usually, they have a sensitive spot that picks up signals from the environment. This point is made of polymers and platinum electrodes.
Most are calibrated by laser, have a good performance and a minimum margin of error.
Speed
Sensors used to detect the speed of an object or vehicle are known as"speedometers".
There are different types of speed sensors, such as wheel sensors, speedometers for vehicles, LIDAR, floor speed radars, doppler radars, speed indicators, pitot tubes, among others.
These sensors are usually used for the synchronization of motors in different industries. They are also useful for controlling the speed or revolutions per minute of a given machine.
On the other hand, on the roads it is common to see speed sensors whose job is to detect the speed of the vehicles that transit through this road.
Temperature
A temperature sensor is an artifact that throws information about the temperature of the medium through an electric impulse.
This electric impulse passes in the form of voltage, and the proportion of this voltage is equivalent to the value of the measured temperature.
There are different types of sensors used to measure temperature. There are the contact sensors, the non-contact sensors, the mechanical sensors and the electrical sensors.
An example of a mechanical sensor is a conventional thermometer and an electric sensor may be a thermistor.
Temperature sensors are used in the industrial field to control the temperature of the artifacts and machines involved in manufacturing processes. In this way, the information taken from the environment can be read and controlled.
Pyroelectric
A pyroelectric sensor or PIR sensor is one that is used to measure the radiation of infrared light emitted by an object within its field.
Each object having a temperature above zero degrees produces caloric energy in the form of radiation. This radiation emits infrared waves that are invisible to the human eye, but can be captured by the PIR sensors.
PIR sensors are classified according to their angle (the amplitude of the area they can cover) in relation to the number of moving elements they can detect within that area.
They are sensors commonly used in everyday applications, such as the automatic door opening system and in general all systems that react to a movement.
When a body moves, an infrared signal is emitted. When this signal is detected by a PIR sensor, it sends a signal to a microcontroller, which will be responsible for translating said signal into a response.
Light
Light sensors are reflective sensors that operate by signal interception. They operate using a stimulus receptor cell sent by a light source, which can be a lamp, an LED, a laser diode, among others.
There are many types of photo-receptor cells, each of these types reacts according to the intensity of the light signal received.
Generally, the light signal can be converted into electrical energy, when captured by photovoltaic cells.
This is the case of solar panels, which capture the free electrons present in sunlight, and transform them into an electric current that can be used to energize a circuit (Olivia, 2010).
Contact
Contact sensors are those that use switches that are activated using physical actuators.
Some Robots Of industrial use they use this type of sensors like"whiskers of cat"or fine wires that allow to detect the proximity of the elements.
Contact sensors are useful for avoiding bumps between objects. For this reason, they are commonly used in the automotive industry in the back bumpers of cars.
Sound
This type of sensor has the ability to capture the sounds of the environment by means of a sonar system or microphone.
They are usually used to receive stimuli such as commands remotely or to measure distances based on the perception of the sound wave.
Sound sensors work similarly to ultrasonic sensors, since the sound wave must propagate through the air present in the medium before it can be detected by the sensor.
References
- Agarwal, T. (2017). In . Retrieved from"Know about Different Types of Sensors with their Applications: edgefx.in
- . Engineers Garage . Obtained from Sensors: Different Types of Sensors: engineersgarage.com
- Olivia, J. E. (December 10, 2010). Retrieved from"SENSOR CLASSIFICATION: thelastlabproject.blogspot.com.br"
- Porto, J.P., & Gardey, A. (2010). from . Obtained from SENSOR: definicion.de
- Sensors and Transducers . (2017). Obtained from Types of Sensors: profesormolina.com.ar.