Quote:
Originally Posted by Greg McKaskle
The higher the camera is mounted the better -- I agree. Fewer objstacles, the cross section of the cylinder is closer to a rectangle, and distance calculations may also be simplified with a smaller angle. The biggest reason, though is to avoid having the camera stare into the lights. Substitute your eyes for the camera, and give it a try. Height helps.
As for a hood. Again do the eye substitution and put on a ball cap. It will help with light from a certain direction, but you still may not be able to avoid looking into the lights in some situations. Continuing the analogy, you may think putting black smudge beneath the camera will help, and it will make the robot to look meaner, but a better implementation would be to avoid shiny materials like lexan in front of and beneath the camera that will reflect overhead lights back into the camera.
Continuing down this line of thought, you may be tempted to put sunglasses on your camera. Good thought, but testing it out, you will find that if set to auto-expose, the camera will just adjust the exposure to rebrighten the entire scene, pretty much the way your eyes do. What about polarizing lenses? Unfortunately, the light from the field isn't polarized, and the target material doesn't polarize the light either, so in that case, polarized lenses work the same as colored ones, and they can't selectively filter out glare or bright spots.
If you find something that works miracles, please share.
Greg McKaskle
|
Greg,
Do the spotlights that FIRST uses put out full spectrum white light?
If not, then can a team (Knowing the height of it's camera, and knowing the size of the target) filter out all but 1 of the 2 colors and track on that?
The reason I'm asking is because (if you know your camera height) you can tell whether your target is on top or bottom by angle within the frame, and (know the size of your target) you can tell how far away it is by the area it fills within the frame.
By only tracking 1 color you can filter out all other light (you cannot easily filter out optically for 2 colors not next to each other within the spectrum) which should let you filter out even the brightest spotlights, unless they put out full spectrum white light.