pic: Tube Sizes can Vary A Lot!

We experienced a lot of issues at Suffield Shakedown with variations in tube size and what I feel is over-inflation of the tubes. As you can see the middle Red Triangle is much larger than the other two. It is so large that when our HP tried to shove it through the slot it wouldn’t fit. We attempted to measure the tubes but were not allowed…

Make sure your manipulator can handle huge variations in tube size.

Having been around in 2007 for Rack 'n Roll, I remember that behind the scenes at CMP, there were these three-sided wooden “boxes” that the volunteers used for blowing up the tubes to ensure that the tubes were all as close to the same size as possible. I’m fairly certain that they will implement another simple way to accomplish uniform sizes for the tubes. They may not be able to do this at scrimmages, but it will more than likely happen at regionals and CMP :slight_smile:

using the bottom blue square tube as a reference, assuming a side length of 25 inches as defined in the manual, the triangle has a side length of 41 inches (11 inches more than the manual says it should be) and a maximum thickness of 14.3 inches!

Build a grabbing device that takes varying inflated tubes out of the equation.

In the real world nothing is ever to spec. Just another part of the challenge.

Frankly I thought the tubes would burst at the inflation levels we saw in Suffield.

Using shop air to inflate tubes is not a problem, IF you know when to stop inflating!

I expect the regionals will have more evenly inflated tubes, but they still won’t all be consistent, and if your manipulator can’t deal with it, you might want to think of ways to modify your manipulator so it can deal with it.

Given the different shapes of the 3 tubes, I can see the discrepancies. BUt here is the official rule from FIRST

While playing LogoMotion, HOSTBOTS manipulate GAME PIECES to accomplish the objectives of
the game. Each GAME PIECE is an inflatable object constructed of 0.3 mm thick vinyl. The body of
each GAME PIECE has a tubular cross-section, nominally between 7 and 8 inches in diameter at
their narrowest. The GAME PIECES are inflated to nominal size, not a specific pressure.

As has been said. If your robot clamp is constructed to fit an exact size, it might not have the ability to clamp down properly. They need to have flexibility built in.

That has nothing to do with the problem of the human player not being able to feed it through the feeding slot.

Read OP’s last statement.
If it doesnt fit through the slot, throw it over and pick it up from the ground.
If you cant pick it up from the ground, read my statement again. :slight_smile:

As far as we found, there is no rule preventing the inflation/deflation of tubes by the human player. Ifa tube is hugely over inflated, couldn’t the FEEDER deflate it slightly?

It’s a good idea, and even if they could, would you really want your HP taking the time to stand there and deflate tubes? Like Ed said, just throw them over the top. It’s a good thought, but I personally would not want my HP spending the time deflating the tubes when they could just toss them over the top.

Just my two cents.

Glen, I agree with you since we can pick up from the floor.

But it has me thinking, what about all of the teams that designed to pickup directly from the Feeder Slot? This strategy is considered viable according to the manual, as tubes are allowed to be fed through the feeder slot. That being said, shouldn’t someone ensure that the game can be played according to the rules? What is the point of the slot if the tubes don’t fit through it? I hope that someone is keeping a close eye on tube inflation at our events.

If a supplier cannot reliably meet their own specs, then they will go out of business. No one wants a supplier they can’t rely on. Things may deviate – but this should be part of the spec sheet.

Of course, people who design their manipulators for the specific diameter FIRST puts in the manual haven’t been in FIRST for long enough. :eek: