Light Follower Robot

Project code:- E37 Project Cost:- INR:- Rs. 7000/- USD:- 170$

Light Follower Robot

The present robo is designed to follow the torch light or laser light .It has three light sensors named as foresight sensor ,left side sensor and right side sensor.based on the fall of light on any of the sensor the robo will move to the desiered direction.. This robo is self powered ,and uses 1.5vX4 battery.

Light Follower Robot Block Diagram Light Follower Robot Block Diagram

Heart of our robo is intel’most power family of microcontroller 8051,we are using U1 5v regulator ic, at89c2051microcontroller.ic U2, IC u3 is ld293 motor driver ic which drives two nos motors m1 and m2..

Circuit operation:
We have fixed three nos light sensors on the fore side on the robo. One is exactly facing ahead in the direction of road other two are fixed on to the either side of the robo facing outer side fron the robo at about 45 degrees.

Working principle of the sensor.all the light sensors are identical so we will only explain one of the sensor. Resistance r2 is a ldr .transister q1 is a pnp transister. Bariable resistance v1 is adjusted in such a way that this transister donot receie conducting voltage on its base whenever a torch light falles on the ldr it’s reistance falls and the voltage at it’s base will fall to negative side and this transiter will go into conduction state current will flow through r3 and r4.

transister q2 will get enough forward voltage and will go into conduction state collector of the transister is connected on to the microcontroller port pin ant it get it’s collector voltage high from the icrocontroller pin pin3 p1.1,pin9 p1.5 and pin11 p1.7 . when ever transister goes into conduction state it will pull doun the particular port pin through resistance r2,r4 or r5. these resistance are current limiting resistors.

Based on the input of the sensors will move in forward direction left or right direction Pin 19 and 18 of the microcontroller controls the motor m1 and pin 15 and 16 of the microcontroller controls the motor m2 pin 17 of the microcontroller is enable pin which enables both the motors to turn on has to stay high in order to turn the motors in any directions When one of the pin becomes high and other pin becomes low motor will turn in one direction reversing the polarity of pin motor will turn other direction

Crystal x1 , C2 & C3 gives the required clock pulse to microcontroller.capacitor r1 and c1 gives the required reset pulse to microcontroller pin no 1.Robo is powered by 6v rechargable battery 1200ma . Capacitor c5 and c6 are for spark quench. C4 is a filter capacitor.
Ic u1 is 7805 regulator ic .it gives regulated 5v dc for the operation of the circuit. Both the motors gets unregulated power direct from the battery connected to pin 16 of the ic u3.

Click here on how to place an order for the project