Encoder Front Page
SRS Home | Front Page | Monthly Issue | Index
Search WWW Search seattlerobotics.org


L.I.R.P. (Light Indicated Robotic Platform)

Jeff Clayton,

lirp.jpg (22326 bytes)

After building a few robots, I decided that I needed to build one that indicates to people what its doing. I watch my robots do there thing, and while I know what the robot is doing, its hard to convey this information with people who dont know how the electronics work. So I decided to build a robot that has LED indicators for every function of the robot. By doing this, people are able to see what sensors are doing what.

bot1.jpg (47288 bytes)

There are three main parts to this robot, the OOPIC controller, the body or chasis, and the interface board. the interface board holds all the LED drivers and the sensor circuitry needed for this robot. the board interfaces the sensors to the OOPIC. LIRP uses bumper sensors, IR proximity detection and IR rangers for wall following behaviors.

bot2.jpg (22815 bytes)

Here is how the robot works, it starts out by moving forwards. The bumpers have priority over all the other sensors with the IR proximity next in line after the bumpers. The IR rangers are used only for perimeter movements. Each bumper has 2 high intensity LED's. when the robot touches something on the right, then the right LED comes on to indicate that it hit something. the robot backs up and finds a new direction. I have 2 bright LED's for the right and left IR proximity sensors so that when it sees something to the left, the left LED comes on as the indication for an object seen to the left. For wall following behaviors I have built a sort of level meter using 5 LED's. Each LED represents a range, Too close, just right, and too far away. It is easy to see how the robot knows how to follow a wall when you can see the constant adjusments indicated by the LED's. I have included a light meter with a 10 LED bar to show light levels. Each servo has 2 LED's to indicate direction of the servos. A green LED for when the servo is reversed, and red for forward motion. This is a really fun robot to watch.

bot3.jpg (30594 bytes)

I have used all 40 IO lines on the OOPIC and I am really close to pulling too much current from the OOPICs 5V regulator. I plan on adding sound to this robot, and I will have to upgrade the OOPICs voltage regulator to supply more current. The OOPICs regulator is rated 5V @ 100mA I need about 300mA to complete this robot. I am really starting to tap into some of the oopics power by useing virtual circuits in my code. All the LED's run in the background of the program and do not interfere with the normal routine that is on the OOPIC.

bot4.jpg (30517 bytes)

On a final note, I will be at the 2001 robotics expo put on by Acroname in Boulder, Colorado. I am entering LIRP into the open floor competition, anyone who will be there, please come say hi to me, I would love to meet others out there who may be as strange as I am.

Have fun building those robots!!!!!

Jeff Clayton