Line following robot; Linebug (Videoclip & Circuit Schematic is added)
Date: Friday, February 04 @ 11:42:58 EST
Linebug is able to find and follow a 2-3cm thick black line drawn over a white surface. 4 IR sensors are housed in a black, plastic box and their signal levels are compared by 4 separate op-amps. Op-amp outputs are then fed into the microcontroller (PIC 16F870) and the micro drives two motors to enable the robot first find, and then follow the black line.
Do you think Neons are only used in Tuned cars? (Auto tuning, power tuning, vinyl tuning etc.) Sure not! Here is our Linebug with its white Neons. Linebug is able to control its neons; can turn them on or off, can give them pulse effects with slow or fast changes, can fade in and fade out them or simply hold their intensity level constant.
Linebug, front view. As you can see, the box is a bit curved, though i didn't be able to find a suitable sized black box, i've made this by cutting and gluing two boxes. Via the 4 holes on the black box, you can see the 4 LEDs inside. When the sensor sees white, the LED is on.
Shots from various angles. The neons really look nice. In fact, our neons are white superbright LEDs. These LEDs are wonder, they are really very bright and powerful. To enable them look like real neons, i've insterted them into white colored semitransparent pipes and glued into place. Used hot silicone as the glue.
The back parts of the pipes are left open, so they generate two light beams towards the back of the robot forming two rocket-like tails. That also didn't look so bad ;)
I've used several parts of multi-holed prototype boards and bamboo sticks which are cut and glued to form a structure to carry the battery above the microcontroller. I've left the mid part a bit curved inside to have a nice bed for the batteries. I've poured a bit hot silicone to the inside sides of the curve to make the bed of the batteries a soft and non-skid place. I've also glued two bamboo sticks to the sides of this battery bed for a small, fastening-rubber
The circuit below carries the 4 IR sensors and housed in the black box.
The IR receiver (black one) and IR LED (transparent) are taken from an old mouse. Of course I tore apart several mice before i've found similar IR receivers and LEDs. Fortunately my flat is full of old mouse everywhere. :). You've probably saw the black paper between the IR transmitter and receiver. That's for disabling them effecting each other directly. The receiver should receive the IR signal reflected from the ground, not the signal directly coming from the LED.
And this is the variable resistor which gives us the ability to tune up the threshold level of IR light which makes the op-amps to change their output statuses.
The project is not complete yet. Until i draw the circuit schematic and get the other documents ready, you can take a look at other sites on the net about line following robots.
Just fill out the google search box below, with search words like "line following robot" etc, and reach a thousand different line followers in a second ;). The search results will popup on a new window, so you won't loose your endtas connection either ;).
Most of those projects you'd find will probably include many different kinds of sensors, line following methods and other very useful information. Take your time and study them.
Linebug Circuit Schematic