
jstarne1

Hello I have some neat ideas for navigation involving QR codes on the ceiling. This ofcourse involves cameras pointed strait up. I believe I may need to fashion a zoom lense on the camera as well. So anyways here are the main questions. I have not tested these yet so I thought I would ask real quick before investing time into testing everything.
1. How far away can the v3 camera read a QR code
2. Can QR codes be placed close together
3. Can ez builder read the QR code in any direction.
I appreciate the responses and as long as the codes can be read in any orientation I believe everyone will like what is next.
2. Yes but the camera will need them far enough apart so it knows which to track. If it detects two at once then you will run in to recognition problems.
3. Yes, upside down, 90 degrees either way all work
Stick them to some plexi, stuff a few LEDs behind, let the white paper diffuse the light and the black ink of the QR code should block it. The camera should pick it up very easily (and it could be passed off as some artistic form of ceiling light).
@Josh, if it's for navigation, you could always use an IR beacon based system (northstar) like the rovio uses if QR isn't going to cut it.
I am still planning on pursuing the IR beacon method to help my bot find its way to the charger. One of my Christmas presents arrived yesterday. It is the Pololu IR Beacon Transceiver Pair. Claims to have a 15ft range. Looks promising.
IR Beacon
http://www.3m.com/product/information/Scotch-Reflective-Tape.html
If you can't get enough contrast from light in the room, try putting a light source near the camera on the robot and using retro reflective tape on the white areas of the QR Code. The tape should allow you to light up the QR code when needed and not need exceptionally bright room lighting. The light source must be near the camera lens. First Robotics recommends a ring around the camera lens. Haven't tried it with QR Codes, but the retro reflective tape lights up targets from a good 15 to 20 feet away with 10 or so Ultrabright narrow angle LEDs in a ring around the camera lens.
I could see the cost adding up pretty quick with that kind of solution, but it is elegant.
Alan
Right now the QR codes and a compass for reading direction sounds the simplest. In any case the home base / charging stations will be used and they have IR beacons. Beer butler has one made by kronor that works great and maybe I could manually make a dock like that for Jarvis.