Introduction: Light Seeking Robot/Car

This is very simple and easy to make light seeking robot

First part of the circuit is a light searching sensor wired around the popular Op-Amp LM358 (U1), which is an 8-pin IC having two inbuilt op-amps. Here the two op-amps are configured in comparator mode, ie the reference voltage is set at the inverting(-) input pin , and then it is compared with the input at non-inverting (+) input pin (reference voltage at inverting input pin can be set with the help of associated potentiometer). When voltage at non-inverting input pin exceeds this reference volatge, output of the comparator goes high , otherwise it remains in low state. 2-channel output from U1 is fed to the inputs of the integrated motor driver ULN2003A.

things you need :


Chassis board
ULN2003A motor driver ( you can also use 2N2222 transistor )

LM358 comparator

some LEDs

2 LDR (light sensors)

some 10k and 1K resistors

2 Gear motors with Wheels

9 volts battery (preferred to use chargeable batteries)

proteus file is attached ;