An Introduction To Sensors...

Today, I have decided to write about 'Sensors': I have chosen this topic because I realised that sensors are omnipresent and make our life much simpler. Sensors are a very common piece of technology used nowadays in the modern world of artificial intelligence and home automation. Sensors tell us about our surroundings and automatically take the action we have programmed them to do.  There are lots of kinds of sensors that we use in our daily lives:

1. Gyroscopic Sensor- Most common place this sensor is used is in phones to sense its orientation. The phone has a gyroscope inside it. A gyroscope maintains its own axis despite the way it is held. That is how the screen rotates when you turn your phone. Please read my blog how do phones sense your orientation for more information.
2. Temperature Sensor- Like a normal thermometer, this sensor helps detect the temperature of the outside air. This sensor does not use the old-fashioned mercury thermometer; instead, it uses a digital thermometer which is more accurate and also safer if the sensor breaks open.
3. Proximity Sensor- As we all know proximity means 'nearness' or 'closeness'. This sensor uses the same technology as dolphins or bats use, ie sending out sound waves to determine the proximity of the closest object (echolocation).  A common use is in cars: when the car is reversing, this sensor activates a beep if the car gets too close to another object.
4. Pressure Sensor- How do computer keys know that you have pressed them? As soon as you apply more than a minimum pressure on the key, a circuit is completed. Thus the computer knows that you have pressed a key. There is a minimum amount of pressure because on the sensor there are multiple other forces that are being applied that you don't want to consider, such as- gravity, air pressure etc. 
5. Smoke Sensor- You may know this sensor as a fire alarm. A smoke sensor checks for elevated amounts of carbon-dioxide, carbon-monoxide and other such gasses that are emitted in case of a fire. As in the pressure sensor, there is a maximum amount of gasses that can be ignored- after all, we also breathe out carbon dioxide and other gasses.
6. Infrared Sensor- You may identify it as an IR sensor. An IR sensor is capable of detecting the heat emitted by an object, based on which it can estimate the dimension, shape etc of the object. These sensors are commonly used in night vision glasses, some telescopes and many other pieces of equipment.
7. Level Sensor- A level sensor, as the name suggests, can detect the level of something. Eg. a level sensor installed in your water tank will let you know when your tank is on the verge of filling and will remind you when to turn off the water source.
8. Motion Sensor- Also known as a motion detector, a motion sensor will identify when some movement has happened. There are 3 kinds of sensors
• Passive Infrared- These sensors are used in home security; they form a virtual grid inside the house. Using infrared light (see sensor number 6 above) they can detect the body heat of a human. Now like most sensors they have a maximum amount of heat that they will ignore as it may be caused by a tube light that has been on for a long time, etc. 
•  Microwave- These sensors send out rays in all directions that bounce back and give precise measurements of the dimensions. 
• Infrared- Same as the microwave
• Ultraviolet- Same as the microwave
9. Accelerometer Sensor- This sensor derives how fast you are going. An example of this would be in ios 11, your phone will automatically put itself in do not disturb mode if you are driving or sitting in a moving vehicle. 
10. Humidity Sensors- These sensors measure the amount of water vapour in the air an any given time. These are used to let people know when your plants need to be watered and will trigger a reminder. 

That is all I have for now. If you have come across any other type of sensors around you, I would be keen to learn and explore with you. Please let me know over email or leave it in the comments section. Thank you.