Event.Details
Events.Thursday
Line.Follower
In this event, the participating teams will be taught how to make a line following robot from scratch. We will provide all the required material along with the circuit diagrams and any help needed in making the circuits. Every team will make a line sensing circuit and then test it on the chassis provided by us. The teams will be allowed to take with them their completed circuits.
Details >>
As the name suggests, a line follower follows a line! Generally it’s either a white line on black background or vice versa. For doing this, it needs two things, first some kind of sensor to detect where the line is and secondly some mechanism to steer along the line.
For detecting the line, we can use two Light Dependent Resistors (LDRs). Otherwise we can also use IR sensor, but they are costly and more complex to use as you can’t “see” the IR. For steering the robot, the differential mechanism in a tricycle formation is used, which simply put is the mechanism in which bot has three tires, front one is idle and the rear two are powered by two independent geared DC motors. For turning left, the left motor is turned off while right is turned on, so it moves in a circle with centre at the left wheel. Similarly right motor is turned off and left turned on for turning in the right hand side.For sensing the line and also for controlling the motors, the following simple circuit can be used. Two circuits of this type are needed, one for each motor and sensor.
The circuit is very basic and easy to use. The LDR and fixed resistor form a potential divider and the voltage at inverting input of comparator (LM339) varies with LDR's resistance, which in turn varies with intensity of light falling on it. The other potential divider formed by variable resistor and fixed resistor gives a reference voltage at non-inverting input of comparator. Comparator drives a transistor, which in turn controls the relay connected to the motor. Here is a pic of line follower in action:
Here is top view with the test track that we used for practice:
P.S. - There is a security deposit of Rs. 50/- per team.
Contact >>
Sumit Tada
sumittada@gmail.com
Registration >>
Click here to register for this event.