team 1389’s vision pipeline for detecting a retro-reflective rope
Thoughts on whether this is viable/useful? our plan is to use it to align with the less visible davits - the ones facing into away from the driver stations.
I certainly don’t see why this would not be useful. As long as it is a legal rope, I would consider this a clever approach to climbing. Odds are the rope is not going to fall straight down. There will likely be some sort of curve to it. To be able to account for this, especially if your rope is not clearly visible, seems very helpful.
While this is definitely a cool idea, I don’t see why your rope would not be visible. If you setup up your rope in the davit that is right in front of you station, it should be pretty visible. And i don’t see any reason why your alliance partners would not let you setup your rope right in front of your station.
Given the high point value and low difficulty of rope climbing (compared to climbing in previous years at least) I would expect almost every elminations alliance to have 2-3 climbers at the higher levels of competition. Once you have more than one, someone has to take one of the rear davits
Retro-reflection requires glass (or other RI-specific transparent material) beads typically, either that or metallic/mirrored surfaces, which are not fibers. I am worried that a retro-reflective rope does not abide by the rules.
If retro-reflective rope is out (TBD), I’d recommend selecting a rope in a color that is not otherwise going to be in the view area, and doing some color filtering before passing an image to your rope finder, or some way to take advantage of parallax.
I am not an inspector, but I would have a hard time considering a rope with “retroreflective filaments” to be a rope. When I think of light bulb filaments (or any other filament), it may be thread-like/fiber-like, but it is still a metal. https://frc-qa.firstinspires.org/qa/tag/ROPE?query=reflective
All that said, I’m still not all that convinced the vision is that much more useful with lining up on the rear rope than just a normal camera without vision. You should still have a pretty good angle for the driver for the rear davits if your not in station 2. And if you’re in station 2, you should have priority for the davit directly in front of you.
Glass beads = not fibers = not allowed. As I feared. 
In this case, we even have a Q&A for it…
https://frc-qa.firstinspires.org/qa/51
There was some argument on CD. We could not figure out if glass beads in rope counted as “flexible” or “fiber”.
No, glass beads are neither flexible nor a fiber.
In all likely hood, for the ROPE shown, glass beads are added as a fillet to some of the rope FILAMENTS. If this holes true, then we need to inquire, for all ROPES, if there is ridged filler in the filaments. Possibilities are talc, mica, and various other minerals. Manufactures rarely publish this info in their standard literature. Likely an MSDA will not be helpful either, IF it exists. Alternately, give the inspectors a microscope and we will do our best.
IMHO if there is a thing called ROPE that is part of a standard product, made by a ROPE manufacturer then it meets the ROPE test. If there is to be a ban on GLASS beads, in any form, Just say so. Like, the ban on metal (in any form).
This is not to say that I think that a rope that has been processed (by the team or others) to glue glass beads to the surface would be legal.