Rope Length: FROM FLOOR

For the SHORTEST rope configuration, what would be the distance from the bottom of the rope to the floor?
For the LONGEST rope configuration, what length of rope would (theoretically) be lying on the floor?

When we did the math, we found that the longest put about 17" to 18" on the floor, and the shortest put the end of the rope about 17" to 18" above the floor. In both cases, we assumed that the rope hung vertically and did not have built-in curl. These may actually be a little long, as we did not account for the angled channel just below the fingers.

Some quick math gets results similar to those posted by Gus above. The bottom edge of the Touchpad is 58 inches off of the floor. From the bottom edge of the Touchpad to the far end of the Davit fingers is about 22 inches (taken from the field CAD). Adding on an additional 2 inches in length for the retaining feature, the shortest possible rope of 63 inches would hang 39 inches below the Touchpad, with its bottom being 19 inches off the floor. Alternatively, the longest possible rope of 96 inches would have about 14 inches laying on the floor.

Thank you both, so much. :slight_smile:

If you want to verify the math yourself, check out section 3.9 TOUCHPAD:

Each TOUCHPAD is a 10 in. (~25 cm) polycarbonate plate mounted 4 ft. 10 in. (~147 cm) above the carpet and used to determine if a ROBOT has successfully latched on to the AIRSHIP (i.e. ready for takeoff) at the end of the MATCH. The plate has a 3 in. (~8 cm) wide by 6 in. (~15 cm) deep rectangular cut-out to aid in assembly and ROPE mounting.

Section 3.4 AIRSHIP:

The hexagonal deck is 5 ft. 10½ in. (~179 cm) wide and 3 ft. ½ in. (~93 cm) above the FIELD carpet. The rail forms an 8 ft. 5 in. (~257 cm) wide hexagon that is 3 ft. 6½ in. (~108 cm) above the deck. Polycarbonate walls connect the deck and rail and angle out from the deck at a 75 deg. angle. PORTS, 13 in. (~33 cm) wide by 19½ in. (~50 cm) holes next to each LIFT, are cut in the three walls facing the ALLIANCE WALL.

And I04:

B. be designed/configured to be at least 5 ft. 3 in. (~160 cm) long measured from the side of the ROPE’S retaining feature (per I04-E) that abuts the DAVIT fingers (L), to the farthest point on the ROPE from this feature.

C. be designed/configured to not exceed a length of 8 ft. (~244 cm) measured from the side of the ROPE’S retaining feature (per I04-E) that abuts the DAVIT fingers (L), to the farthest point on the ROPE from this feature.

Those sections of the rule book provide most of the dimensions you need to get close, but remember the field drawings really provide all of the official dimensions (Per multiple Q&A responses, such as Q133). You can find the drawings here: https://firstfrc.blob.core.windows.net/frc2017/Drawings/2017FieldComponents.pdf

Start by looking at page 75, then figure out how that gets attached to the airship to determine total height.

Is it not possible to heavy knot up the strap or rope up high or down low so you would have a huge gap to the floor. Yes I know about the height limitations give me a break. So here is the quest my PHD mind set friends. The robot starts to climb. Bumper zone out the window. Volume size leaves the building with ELVIS. So why can’t the robot start to climb without the rope/strap. I can’t wait for all my smarter peeps to shoot me full of buck shot. I love it when, I’m put in my place. What do they call those cars out in LA, that hop up and down, go back and forth Low Riders. Thomas (just give me crabcake) McCubbin

what

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seriously i just keep reading this and i end up with more questions

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I’m not sure there is a coherent thought in the post, so any questions it generates is probably for not.

If you’re asking what I think you’re asking, the answer is no, per I04-B, as updated in Team Update 02:

A ROPE must meet the following criteria (see Figure 9-2 for letter references):
B. be designed/configured to be at least 5 ft. 3 in. (~160 cm) long (measured end to end) measured from the side of the ROPE’S retaining feature (per I04-E) that abuts the DAVIT fingers (L), to the farthest point on the ROPE from this feature.

As to geometry questions, the “size box” and the bumper zone move with the parts of the robot which would be touching the floor if it weren’t hanging from the rope.

From the blue box for G04:

These measurements are intended to be made as if the ROBOT is resting on a flat floor, not relative to the height of the ROBOT from the FIELD carpet.

And the blue box for R23 is like unto it:

This measurement is intended to be made as if the ROBOT is resting on a flat floor (without changing the ROBOT configuration), not relative to the height of the ROBOT from the FIELD carpet. Examples include: