Introduction:
It is a very famous concept arising these days which means “Internet of Things” which refers to the collective network of connected devices and the technology that facilitates communication between devices and the cloud, as well as between the devices themselves.
IoT sensors are special types of sensors that provide a usable output after gaining information from a certain input, processing it and then interpretant sensor interpret the physical parameter and convert it into signal for processing(eg. electrical ,Mechanical etc).
These sensors include pressure, temperature, humidity, moisture, gas sensors, sound sensors, etc. All are designed exclusively to measure a particular physical attribute in the surrounding environment. The output of the sensor is human-readable and interpretable things that can be of great use to the human community like capacitance, resistance, and change in characteristics.
There are Five Types of Iot:
a)What is Consumer Internet of Things (CIoT)?
b)What is Commercial Internet of Things?
c)What is Industrial Internet of Things (IIoT)?
d)What is Infrastructure Internet of Things?
e)What is the Internet of Military Things (IoMT)?
Sensor Classification :
a)Passive & Active:-The active sensor can sense the input independently. eg. Radar, sounder, and laser altimeter sensors. The passive sensors can sense the input independently. eg, Accelerometer, Thermocouple, Soil moisture etc.
b)Analog & digital:-The output of the Analog sensor is in analog or graphical form of a continuous function .eg-Temperature sensor, LDR, analog pressure sensor.
Digital sensor: The output of a digital sensor is in Digital form in the form of bit. It requires some extra equipment’s for the conversion of bit for digital value.
eg: Passive infrared (PIR) sensor and digital temperature sensor(DS1620).
c) Scalar & vector: scaler sensor only detects the input parameter magnitude not the direction.eg: temperature, gas, strain, color and smoke sensor.
Vector sensor: This type of sensor detect the input Parameter magnitude as well as direction and orientation of the input parameter. eg: Accelerometer, gyroscope, magnetic field and motion detector sensors.
Other Type Of Sensor:
a)Electrical sensor :Electrical proximity sensors may be contact or non contact. Simple contact sensors operate by making the sensor and the component complete an electrical circuit. Non- contact electrical proximity sensors rely on the electrical principles of either induction for detecting m
etals or capacitance for detecting non metals as well.
b)Light sensor: Light sensor is also known as photo sensors and one of the important sensor. Light dependent resistor or LDR is a simple light sensor available today. The property of LDR is that its resistance is inversely proportional to the intensity of the light i.e. when the intensity of light increases, it’s resistance decreases and vise versa.
c)Touch sensor: Detection of something like a touch of finger or a stylus is known as touch sensor. It’s name suggests that detection of something.
They are classified into two types:
- Resistive type
- Capacitive type
Today almost all modern touch sensors are of capacitive types. Because they are more accurate and have better signal to noise ratio.
Range sensing: Range sensing concerns detecting how near or far a component is from the sensing position, although it can also be used as proximity sensors.
Distance or range sensors use non-contact analog techniques. Short range sensing, between a few milli
meters and a few hundred millimeters is carried out using electrical capacitance, inductance and Magnetic technique.
Longer range sensing is carried out using transmitted energy waves of various types eg radio waves, sound waves and lasers.
d) Mechanical sensor: Any suitable mechanical / electrical switch may be adopted but because a certain amount of force is required to operate a mechanical switch it is common to use micro-switches.
Pneumatic sensor: These proximity sensors operate by breaking or disturbing an air flow. The pneumatic proximity sensor is an example of a contact type sensor. These cannot be used where light components may be blown away.
e)Optical sensor: In there simplest form, optical proximity sensors operate by breaking a light beam which falls onto a light sensitive device such as a photocell. These are examples of non contact sensors. Care must be exercised with the lighting environment of these sensors for example optical sensors can be blinded by flashes from arc welding processes, airborne dust and smoke clouds may impede light transmission etc.
Conclusion:
The sensor plays an important role in our day to day life in almost all fields. The main application of IoT sensor is in agriculture, Electronics, Electrical, Automation, Electronics etc.
With the coming of smart IoT sensor ,the scenario has changes a loT. The interpretation and grasping of data has become so much easy that the accurate analysis can be done in a more accurate way thus these
sensor have become one of the most demanding type od sensor in the field of engineering and all other fields.
