Sensors are a very important building block in the IoT world. There are Different Types Of IoT Sensors in the IoT world. In IoT Devices, having hardware is classified as General Devices and Sensing Devices.


What is Sensor? Different types of IoT Sensors





 

WHAT IS SENSOR?

A sensor is a device that detects or measures a physical property and responds to it. A sensor detects changes in the ambient conditions or a system and processes the information in a certain specified manner in which it is asked to do so basically sensors have the capabilities to study and observe the ambient conditions and on the basis of the changes they respond to it.

 

TYPES OF IoT SENSORS

IoT Devices, having hardware, are classified as General Devices and Sensing Devices. Different Types Of IoT Sensors in the IoT world are following:


TEMPERATURE SENSORS

Temperature sensors detect the temperature of the air or a physical object and concert that temperature level into an electrical signal that can be calibrated accurately to reflect the measured temperature. These sensors could monitor the temperature of the soil to help with agricultural output or the temperature of a bearing operating in a critical piece of equipment to sense when it might overheat or nearing the point of failure.

Some sub-categories of temperature sensors

Thermocouples

RTDs (resistance temperature detectors)

Thermistors

Semiconductor based integrated circuits (IC)

 

MOTION SENSORS

Motion sensors or detectors can sense the movement of a physical object by using any of the several technologies, including passive infrared (PIR), microwave detection, or ultrasonic which uses sound to detect objects. We can use these sensors in security and intrusion detection systems, it can also be used to automate the control of doors, sinks air conditioning and heating, or other systems.

Ultrasonic :

Basically, in terms of industrial application ultrasonic sensors are characterized by their reliability and outstanding versatility also ultrasonic sensors can solve even the most complex tasks because they have a very high precision which we can call millimeter precision also and more importantly, ultrasonic sensors are preferred because their measuring methods work reliability in all different conditions which is a very good advantage considering the different types of sensors that are available which may work in some scenarios, some might not work in other scenarios whereas ultrasonic sensors work in most of the scenarios so they are quite reliable.

Passive infrared :

A passive infrared sensor is an electronic sensor, and it measures infrared light. It uses infrared light to measure an object in its view, also they are more used in you know PIR-based motion detectors.

 

PRESSURE SENSORS:

Pressure sensors measure the pressure or force per unit area applied to the sensor and can detect things such as atmospheric pressure, the pressure of a stored gas or liquid in a sealed system such as a tank or pressure the vessel or the weight of the object.

 

LEVEL SENSORS

Level sensors translate the level of the liquid relative to a benchmark normal value into a signal. There are two basic level measurements types:

Continuous level sensor

Point level sensor

Example: Fuel gauges display the level of fuel in a vehicle’s tank as an example, which provides a continuous level reading. There are point level sensors, which go-no/go or digital representative of the level of the liquid. Some automobiles have a light that illuminates when the fuel is very close to empty, acting as an alarm that warns the driver that fuel is about to run out completely.

 

HUMIDITY SENSORS

Humidity sensors can detect the relative humidity of the air or the other gas, which is a measure of the amount of water vapor contained in that gas. The most commonly used term is Relative Humidity (RH).

Controlling environmental conditions is critical it the production processes of material and humidity sensors enable readings to be taken and changes made it mitigate increasing or decreasing levels.

We can find their applications and use in Industrial & residential domain for heating, ventilating, and air conditioning systems control. A common application is in HVAC systems to maintain desired comfort levels.


IMAGE SENSORS:

Image sensors function to capture images to be digitally stored for processing. License plate readers are an example, as well as facial recognition systems. Automated production lines can use image sensors to detect issues of high quality, such as how well a surface is painted after leaving the spray booth.

Types of image sensors

CCD (charge-coupled device).

CMOS (complementary metal-oxide-semiconductor) imagers.

 

PROXIMITY SENSORS

Proximity sensors can detect the presence or absence of objects that approach the sensor through a variety of different technology designs. These approaches include:

Inductive sensors: Inductive sensors are useful for the detection of metal objects.

Capacitive sensors: Capacitive sensors function based on objects having a different dielectric constant than that of air.

Photoelectric sensors: photoelectric sensors rely on a beam of light to illuminate and reflect back from an object. They are also used for long-distance sensing or to sense non-metal objects.

Ultrasonic sensors: ultrasonic sensors use a sound signal to detect an object nearing the sensor.

 

WATER QUALITY SENSORS

The importance of water to human beings on earth not only for drinking but as a key ingredient needed in many production processes shows the need to be able to sense and measure parameters around water quality. Some of the most common kinds of water sensors are:

Chemical presence (such as chlorine levels or fluoride levels)

Oxygen level (which may affect the growth of algae and bacteria)

Electrical conductivity (which can show the level of ions present in water)

pH level (a reflection of the relative acidity or alkalinity of the water)

  

CHEMICAL SENSORS

Chemical sensors detect specific chemical substances which may inadvertently be leaked from their containers into spaces that are occupied by personnel and are useful in controlling industrial process conditions.

There are some common kinds of chemical sensors

Semiconductor gas sensor

Electrochemical gas sensor

Contact combustion gas sensor

Optical gas sensor

Polymer gas sensor

 

GAS SENSORS

Related to chemical sensors, gas sensors are tuned to detect the presence of combustible, toxic, or flammable gas in the vicinity of the sensor. Like chemical sensors, they are used in many industries such as manufacturing, agriculture, and health and used for air quality monitoring, detection of toxic or combustible gas, oil & gas industries, chemical laboratory research, pharmaceutical & petrochemical, etc.

Examples of specific gases that can be detected include:

Bromine

Carbon Monoxide

Chlorine

Chlorine Dioxide

Ethylene

Ethylene Oxide

Formaldehyde

 

SMOKE SENSORS

Smoke sensors pick up the presence of smoke conditions, which could be an indication of a fire typically using optimal (photoelectric detection) or ionization detection.

Photoelectric detectors

Photoelectric detectors work by using a light-sensing chamber. As smoke enters the chamber it disrupts the path of a laser and triggers the alarm. These detectors are better at sensing slow-burning or smoldering fires.

Ionization detectors

Ionization detectors are used to electrically charged plates to ionize the air in the sensor. When smoke enters the detector, it disrupts the flow of the ions and triggers the alarm. Ionization detectors are stronger at detecting fast flaming fires,

 

ACCELERATION SENSORS:

While motion sensors detect the movement of an object, acceleration sensors or accelerometers, as they are also known, detect the rate of change of velocity of an object. This change may be because of a free-fall condition, a sudden vibration that is causing movement with speed changes, or rotational motion (a directional change). There are several technologies that are employed in acceleration sensors, include:

Half-effect sensors (which rely on measuring changes in magnetic fields)

Capacitive sensors (which depend on measuring changes in voltage from two surfaces)

Piezoelectric sensors (which generate a voltage that changes based on pressure from distortion of the sensor)

 

GYROSCOPIC SENSORS

Gyroscopes or gyroscopic sensors are used to measure the rotation of an object and determine the rate of its movement called angular velocity, using a 3 axis-system. These sensors enable the determination of the orientation of the object without having to visibly observe it.

 

OPTIMAL SENSORS

A sensor that measures the physical quantity of light rays and converts it into an electric signal which can be easily readable by a user or an electronic instruments/device is called an optical sensor. These sensors have found use in healthcare, environment monitoring, energy, aeroplane and many more industries.

Following are the key optimal sensors

Photodetector

Fiber optics

Pyrometer

Proximity & Infrared

 

These Different Types Of IoT Sensors are becoming more popular in all fields and IoT is going to become even smarter in the future. It simply helps with the automation of various processes, making these systems quite useful for both regular consumers and businesses.