Vision Processing - How Bright is Too Bright?

A huge percentage of Robots this year (that go for the high goal) are using Vision Tracking in order to acquire the target. It’s great to see people diving into the world of Vision Tracking and with the release of the GRIP Computer Vision Engine, it’s good to see this is getting more accessible.

But about those bright, blinding Green LEDs. How bright is too bright?
I’ve seen teams use 1 ring all the way up to 4+ rings, providing a power that rivals that of the sun itself. Of course, a visual light is needed for (most, hint hint) vision systems to acquire the retroreflective target, and green is the most suitable hue for that, but how bright do you need it to be before it becomes a nuisance?

Some things to consider:

  1. Blinding the audience
  2. Sensor Bloom on Recording Cameras / Your own Vision Tracking System
  3. If the green light reflects off of the tower itself, it could distract other robots with a weaker light (it’s still a green hue, and with 4+ rings, you could light up a small forest).
  4. Distracting drivers on the opposite alliance / Field Staff (see: Blinding)

I suspect in some configurations, there may be violations of R9-A and R9-C.

How much light do you think is needed before it becomes “Too Bright”?

At Hatboro Horsham district. we were told to cover 1 ring of leds. I believe the field reset people were the ones who complained. We intend to turn ours on and off as needed to try and eliminate the complaints.

I fully understand the brighter the light the easier it is to track, but really some of these teams have WAY too bright lights and i’m amazed they are allowed to run a game with them. Those aren’t just MAJOR distractions to the opposing alliance but if it shines directly at them they are pretty blinding as well. As far as I was aware this is completely against the rules, even if done unintentionally so I have no idea how they are getting away with it.

This is one reason we went with IR leds. we still run them VERY bright but they are completely invisible to human eyeballs so no issues!

I actually have photo sensitivity which ought to make bright lights fun. How do refs flag disruptive lights does someone yell ow?

We’re using a Kinect as a camera, with the IR stream turned on. No visible lights, and the High Goal sticks out like a sore thumb.

Same for our team at Hatboro. We we had two LED rings, one brighter than the other and were told to cut down to one ring at the beginning of the competition. Later on we were allowed to go back up to two rings but ended up dialing it back down to one after a team talked to the referee about the brightness. I felt sorry for the referees and inspectors because it was hard to monitor and saw what is allowed without a black/white rule. Maybe a limit should be placed on dissipated power to the LEDs?

This is the main concern. Those lights can be extremely bright, especially when there is more than 1 ring.

From what i can recall alliance members cant call fouls so whats the deal when ir happens my plan was post match notifying a ref to keep eyes on a tam. Our team wants to run leds on our robot for non decorative purposes but im concerned it might mess with other teams. Does anybody have experience with that.

The way my team has our camera mounted, a ring led won’t fit around it so we cut strips of LEDs about 5 inches long, and stacked 3 of them over each other to put on each side. We haven’t tried it out with vision tracking yet but when you put the LEDs next to each other and look inbetween (like if the camera was there) it completely lights up the tape on the tower and makes it look completely green. We may have to dial it down a little bit.

Since our initial testing at Zebravision Labs showed that the tape on the goals is not in fact retro-reflective to a pumped x-ray laser source* (talk about false advertising), we decided to go with the approach of one of the smaller rings per camera. Still seems a bit bright at close range but it is workable for now for our planned shooting distances.

The trouble with trying to fine tune this so it is just bright but not too bright is a lack of access to to an actual field with realistic lighting conditions. You can (relatively) easily build a goal, but guessing how much interference you’ll have from other lights is tough. Better to be safe and a little overpowered than right on the edge and have it fail in a match if your guess is wrong. Hopefully the refs will be a bit lenient and understand that challenge. Plus think of all the money they’re saving on spray tans.

    • Don’t thank me, thank an unprecedented 60 year military buildup.