What's the best rope?

[Chris is me]

Originally Posted by GeeTwo

Velcro is not composed of twisted or braided strands, unless you consider individual polymer molecules strands and are looking at it under a really good microscope. Feel free to ask on Q&A, but this seems like a pretty solid no to me.

You omitted the verbiage of the rule that makes Velcro legal from your definition, specifically "woven". Loop-side Velcro consists of very thin strands woven together, sometimes with a fabric backing that is also woven. Sometimes the backing and the Velcro loops are even interwoven! This means certain strips of Velcro clearly meet the rules as written. I suspect the rules will probably be changed to add a Velcro exception so that we don't all just have winches made of Velcro that can be designed in five minutes, but as of now it doesn't seem very ambiguous.

[Levi Madden]

Originally Posted by carpedav000

So according to the rules, velcro may be considered a rope as it's flexible and non metallic. Is this correct?

Just remember that G15-C states you can not attach to the field using hook and loop (AKA velcro). When you add your own rope, it becomes part of the field, therefor, you could use velcro as a rope, but you can not attach to it.

[carpedav000]

Originally Posted by Levi Madden

Just remember that G15-C states you can not attach to the field using hook and loop (AKA velcro). When you add your own rope, it becomes part of the field, therefor, you could use velcro as a rope, but you can not attach to it.

I believe this only applies if you use the velcro to strategically hold the rope in place by attatching it to the carpet.

[icomella]

Yes, but the loops can only be 10" in diameter.

[Maxwellfire]

I was thinking about something like this for our team. There's no minimum diameter listed, and I think that coiling a smaller rope would be easier. (Wrapping the field rope around a pulley seemed impossible). The only question is whether you can tie a large enough knot in the end to satisfy the > 1" requirement at the top.

[engunneer]

Originally Posted by Maxwellfire

I was thinking about something like this for our team. There's no minimum diameter listed, and I think that coiling a smaller rope would be easier. (Wrapping the field rope around a pulley seemed impossible). The only question is whether you can tie a large enough knot in the end to satisfy the > 1" requirement at the top.

getting a 1" know is just a matter of a bigger more complicated knot (I suggest a monkey fist in the extreme case).

I'm not sure i would trust a robot to just a 325 lb tensile strength. a robot will be a pretty dynamic load, and the rating goes down quickly if there is any damage. Test test test!

[GeeTwo]

Originally Posted by Maxwellfire

The only question is whether you can tie a large enough knot in the end to satisfy the > 1" requirement at the top.

Google "Monkeys Fist Knot". You can start with an overhand knot and add larger and larger monkey's fists around them.

[Riri700]

Originally Posted by Moonsault

Does this mean it can be looped also?

The rule book states that you can use a loop. But it cant be rigid? it needs to be loose. So if pulled on it tightens. And it cannot be any larger than 10" in diameter.

This can be found on page 100 for specifics.

[COL Woodchuck]

Just remember that G15-C states you can not attach to the field using hook and loop (AKA velcro). When you add your own rope, it becomes part of the field, therefor, you could use velcro as a rope, but you can not attach to it.

I believe the rules in G15 make an exception on the rope so a velcro rope of "loop" and a winch drum with "hooks" would be allowed.

From G15:
Items A-G exclude ROPES installed on an ALLIANCE’S AIRSHIP.
A. Grabbing
B. Grasping
C. Attaching to (including the use of hook-and-loop tape against the FIELD carpet)
D. Grappling
E. Hanging
F. Deforming
G. Becoming entangled

[Kevin Sevcik]

Originally Posted by Riri700

The rule book states that you can use a loop. But it cant be rigid? it needs to be loose. So if pulled on it tightens. And it cannot be any larger than 10" in diameter.

This can be found on page 100 for specifics.

The field drawing doesn't show anything nice about the 90 degree turn the rope makes in the davit. It's shown as a square tube butted against sheet steel bent into a channel, with some weld. I wouldn't expect it to be sharp, but it's not going to be nicely rounded either. And a smaller rope is much more likely to swing and scrape across the edge than a larger one.

[SpadeSeveren]

It seems to my team that you can do any number of things to your rope, so long as it follows the few guidelines. This means you could climb very reliably. I personally think that you should supply your own rope, and have one or two backup ropes, in case one gets damaged. Using the supplied rope creates inconsistency and is overall not reliable, and you can't get the benefits of knots or special material.

My team has strongly considered using a certain climbing rope that has retroreflective fabrics weaved into it, to help with positioning, similar to the one shown here: http://searchgear.com/pmiretroreflectiverope.aspx

However, to answer your question, there is not a definite "best kind" of rope, as it depends on your team.

[engunneer]

Originally Posted by SpadeSeveren

My team has strongly considered using a certain climbing rope that has retroreflective fabrics weaved into it, to help with positioning, similar to the one shown here: http://searchgear.com/pmiretroreflectiverope.aspx

As an inspector, that rope would not pass my inspection and would be brought to the LRI as it contains glass beads (which are not fibers or flexible, per I04).

[Fusion_Clint]

Originally Posted by engunneer

As an inspector, that rope would not pass my inspection and would be brought to the LRI as it contains glass beads (which are not fibers or flexible, per I04).

And you would be wrong. Please read the whole rule. Assuming the linked rope would not extend up more than 12 inches from the point it is held is should be deemed legal. Glass is certainly non-metallic, and "fiber" can really mean anything.


IO4
D. consist entirely of flexible, non-metallic fibers twisted, tied, woven, or braided together except for the last 4 in. (~10 cm) of each end which may be whipped, fused, covered in heat shrink or tape, or dipped in a coating material to prevent fraying.

Blue note "Flexible means that if the ROPE is held at any point, it should not extend more than 12” above the point where it is held. ROPES are meant to be pulled, not pushed."

[engunneer]

Originally Posted by Fusion_Clint

And you would be wrong. Please read the whole rule.

you'd be hard pressed to argue that glass beads are "flexible, non-metallic fibers". entirely means entirely. Sure, the linked rope likely meets the definition given for flexible, but the rule describes more properties of the rope than that. It would be legal IMO to have a rope made of glass fibers, as long as it also meets every other rule, such as safety rules.

also, it is never wrong for an inspector to bring a questionable item to the LRI for a ruling.

Lastly, I assure you that i have indeed read the rule multiple times. I have a few years of experience inspecting bots, and over a dozen years reading FRC rulebooks.

[Fusion_Clint]

The blue note explicitly tells you what flexible means in this context. You can be that guy if you need to be.