Part 3 - Giving Robots the Power to Sense; Arduino Sensors


Hello, This is in continuation to the previous two blogs of the series (How to start robotics at home)

Do watch them first! It will be helpful :)

Click them to view!


Now talking in general about the sensors, Let me first explain to you their use and importance. We all use the words: Automatic/ Autonomous/ Self working robots. Now, these are sensors that make us feel their autonomous behavior.

Let me explain to you with an example,

For instance, if you see a robot car moving and then stops after someone comes in front of it. And no one is controlling, then you may feel that it is automatic. But there are sensors attached to the car and it is programmed like that.

For this particular case, Ultrasonic Sensors are attached which measure the distance from the object (or person) in front of it. Now, it is coded that if the distance is less than 5 cm (it's on you to change these values) from that object, then it must stop rotating the wheels of the robotic car.

Hence it's all about sensors in a robot that gives those unbelievable powers (just like a human).

Now let's study the types of sensors in detail

1) Moisture Sensor

Function: It's simple, As the name suggests. These are used to sense moisture in a particular thing.

Used in: It is used widely in agriculture prototype machines where it can sense moisture in the soil. I used the same in making Autonomous Plant Watering Rover. Check Here

2) IR Sensor

Function: The principle of an IR sensor working as an Object Detection Sensor can be explained using the following figure. An IR sensor consists of an IR LED and an IR Photodiode; together they are called as Photo – Coupler or Opto – Coupler.

When the IR transmitter emits radiation, it reaches the object and some of the radiation reflects back to the IR receiver. Based on the intensity of the reception by the IR receiver, the output of the sensor is defined.

Used in:

I used it in making LINE FOLLOWER ROVER. As the name suggests rover follows a black line. So, it sensors stick to the black tape, don't distract from the path and command the wheels of the rover accordingly. The use of infrared sensors to accurately measure the chemical composition of materials or gases in military applications is well known. Now, however, given their rapidly declining price tag, these IR sensors are gaining traction in Internet of Things M2M applications, including medical diagnostics, imaging, and industrial process controls, fire detection and remote gas leak detection, pollution monitoring, and real-time combustion control.

3) Fire Detection Sensor

Function: A flame detector is a sensor designed to detect and respond to the presence of a flame or fire. Responses to a detected flame depend on the installation but can include sounding an alarm, deactivating a fuel line (such as a propane or a natural gas line), and activating a fire suppression system.

Used in: Made a Video of Arduino Project using Flame Detector. It is simple and clear. Have a look :)

4) Humidity and Rain Detection Sensor


The rain sensor detects water that comes short-circuiting the tape of the printed circuits. The sensor acts as a variable resistance that will change status: the resistance increases when the sensor is wet and the resistance is lower when the sensor is dry.

Used in: Made a Video on Rain sensor Arduino project. When rain falls on sensor, the shutters overhead activates and protect the cars from rain. This will be discussed in detail soon.

5) Knock Sensor

Function: A Knock Sensor or a Vibration Sensor is a simple device that detects vibrations or shocks from knocking or tapping it. It is basically an electronic switch which normally open. When it detects any shock or vibrations, it closes (for that moment and returns back to its default open position).

Used in: Now this can give you HARRY POTTER vibes, where you can simply knock the door and it opens slowly at constant speed. Isn't it interesting. Demo soon for this. Sign up for updates at mailbox

One more simple example for knock sensor:


That's it for now guys!. There are hundreds of sensors which are useful. I have explained you the important and widely used sensors to get an idea of the importance.

In the coming two blogs in continuation of series, I will discuss some of the basic projects and two main interesting projects. You are definitely going to love it.

Sign up now! Getting the next to blogs soon in your mailbox.

Bye till then:)

11 views0 comments