Arduino Light Controlled Bot

Introduction: Arduino Light Controlled Bot

About: Hello my name is Sanu Bhattacharya, I am an Engineering student of RCCIIT. I enjoy making Electronics/Robotics Projects. PLEASE VOTE FOR MY PROJECT IN DIFFERENT CATEGORIES (top right).

This is an Arduino Robot that is Controlled by LIGHT!!!!

The only Sensor it uses are a trio of LDR.

The 3 LDRs are situated at 3 different places on the Bot. ie, Front, Left, Right.

When Light of Sufficient Intensity falls on either of these LDRs, The Bot Moves in its Repective Direction.

The Project Is Very easy and Enjoyable and does not require any Engineering or Programming knowledge.


Step 1: Components Required

1. Arduino uno (with cable) or a similar micro-controller.

2. A robotic Chassis with motors and wheels.

3. A mini breadboard.

4. LDR 3 pieces.

5. l293d motor driver IC.

6. Two 9v Batteries.

7. Battery caps and 2.1mm Arduino snap.

8. Jumper wires.

9. 100 kohm Resistors 3 pieces.

10. PC with Arduino IDE installed.

Step 2: Calibration of LDR

Connect the LDR as shown in the above picture.

That is connect +5v to either of the pin and Connect 100 kohm Resistor from the other pin to the ground.

Connect a Jumper wire from the second pin to Analog Pin 0 of your Arduino Uno.

Upload The Code Given Below and open The serial Monitor.

You Will See A Bunch of Values streaming from Somewhere above 600 if its a well lit room, Now Bring Your Flash Light and Light It Over the LDR.

The Values In The Serial Monitor Will Jump To a much Higher array of values.

Record the lowest of these values, mine was 920.

Do it For all 3 LDRs.

Connect the LDRs at 3 Different Places on The Breadboard devoid of Obstruction.


Step 3: Connecting L293d Motor Driver IC

Connect the L293d Motor Driver on your Breadboard. Connect pins as follows:-

(i) 1, 9, 16 to 5v.

(ii) 4,5,12,13 to ground.

(iii) Pins 2 & 7 of IC to Pins 8 & 9 of Arduino respectively.

(iv) 3 & 6 to the terminals of Motor1.

(v) Pins 15 & 10 of IC to 5 & 4 or Arduino respectively.

(vi) 14 & 11 to terminals of Motor2.

(vii) Pin 8 of IC should be Connected to the positive terminal of an external battery, the ground of the battery should be connected to the common ground.

*The Above Diagram Shows Only 1 Motor for simplicity, The Other Connections are same as above.

Upload The Code Below.

And check if The Bot is Moving In The Forward Direction or not, if its moving in a different Direction, interchange the pin numbers at the Start of the code.

Step 4: Final Step

After Connecting the l293d ic check whether all the LDRs are connected properly.

Once this is Done, Open the Code Below.

Replace the Calibrations LDR values that You obtained in Step 1 for each Respective LDR. (picture Above).

Now Upload The Code.

The Video Shows the Bot in Working Condition.

For any problems please write it in the comments.

Thank You.


Make it Move Contest 2016

Participated in the
Make it Move Contest 2016

Sensors Contest 2016

Participated in the
Sensors Contest 2016

Robotics Contest 2016

Participated in the
Robotics Contest 2016

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