Proximity Sensor: All you need to know about it.

A number of significant developments in various fields have been occurred during the 20th century- the digital computer, improvement in data-storage technology and software to write computer programs, advances in sensor technology and the derivation of mathematical control theory. All this developments have contributed to progress in automation technology. The proximity sensor is the most important data collecting device of any automation system. 

 

Contents:

1. What is proximity sensor?

2. Classifications of proximity sensor.

3. How does a proximity sensor work?

4. Application areas of proximity sensor.

5. How are these sensors used real life?

6. How proximity sensor is used in industry?

What is a proximity Sensor?

        The Proximity sensor is a sensor that is able to detect the presence of any nearby object without any physical contact.

        A proximity sensor is a non-contact sensor that detects the presence of an object when it enters the sensor's field.

Classifications of proximity sensors?

    The two most commonly used proximity sensors are the inductive proximity sensor and the capacitive proximity sensor.

    Other types of proximity sensors are Ultrasonic, Magnetic, and IR proximity sensors. The IR sensor can be classified into two types: reflective and through-beam.

 How does a proximity sensor work?

        There are many types of proximity sensors and they each sense the target in distinct ways. Depending on the type of proximity sensor sound, and light. infrared radiation(IR) or electromagnetic fields is utilized to detect the target.

        An inductive proximity sensor can only detect metal targets. This is because the sensor utilizes an electromagnetic field to detect the target. When a metal target enters into the electromagnetic field, the inductive characteristics of the metal target change the sensor field's properties.

        On the other hand, capacitive proximity sensors are not limited to metallic targets. These are capable of detecting anything that can carry an electrical charge. Like an inductive sensor,  it also produces an electrostatic field. When an object approaches the sensing area, the capacitance of both plates increases, resulting in oscillator amplitude gain. this resulted in amplitude gain triggers sensor output switch. 

        IR proximity sensors detect objects when the emitted light from the sensor is reflected back at the photoelectric receiver or when the target breaks the beam of light between the sensor's emitter and receiver. 

    Ultrasonic proximity sensors emit a high-pitched sound to detect the target object. The distance measurement is possible by this sensor. The sensor-to-target distance can be determined by how long the sound takes to reflect back to the sensor. 

         Magnetic proximity sensors can only be used to detect permanent magnets.

 Application areas of proximity sensor?

        Proximity sensors are used in phones, recycling plant, self-driving cars, anti-aircraft system, assembly line of any process plant and so on. 

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How are sensors used in real life?

    In day-to-day life, you have to go through many sensors continuously for example when making a cup of tea the kettle will use temperature sensor to ensure it reaches the right temperature and a coffee machine uses pressure switches to monitor the amount of liquid dispensed.

Other example of home appliances which use sensors are heating system like room heater, washing machine, dishwashers and so on.

When travelling to work, many vehicles including cars, trains, buses etc. all use sensors to monitor oil temperature and pressure, throttle and steering systems, engine RPM and vehicle speed and so many aspects.

Now we will focus on the use of proximity sensor in our real day to day life.

 1. Usage on Smartphone

    The proximity sensors are used in smartphone to detect any nearby object. whenever you take it to your ear the screen light turns off, this is done by using proximity sensor.

2. Usage in Parking

    The proximity sensor can be used in your parking system to avoid the collision of car with any wall or pillar. To detect the unlawful entry it can also be used. 

3. Usage in automatic faucet

    The automatic faucet which is also known as a sensor tap usually uses an infrared type proximity sensor to detect the nearby object.  

4. Usage in security

    If you think a highly secured area no one is allowed to go there for a specific time period. How will you ensure that? the solution is proximity sensor. 

5. Usage in motion detection system.

    Instantly as you come to your home entrance the front door outside light will be turn on. To turn on the light it's required to detect your motion that is possible by using proximity sensor. 

How proximity sensor is used in industry?

1. Usage in automation system

In the industrial automation proximity sensor is used in many aspects.

2. Usage in counter system

In the production process line the number of product counting is very important.

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