How much does the low rung of the hangar spin?

Hi from 7127 Longmetal Robotics! The low rung of the hangar definitely has some spin to it, but it’s hard to find how much it spins in the manual. Does anyone know?

There probably isn’t an easy way to know exactly what the spin will be like until you actually feel it on the field.

Does anyone have a theory on why the game makers made it spin?

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I really really hate this.
We built the low cost version and someone from FIRST that I know commented that it is the not same as the real field.
I wish games and fields could have crucial elements as close to possible what most teams could get and setup with the low cost version.

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I don’t think just hitting the like button expresses how much I agree with this statement.

Its honestly somewhat embarrassing that this is an issue every year.

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I feel the same way. This year also has the variability of cargo bouncing out of the upper hub, which is nearly impossible to replicate without shelling out $800.

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We Just got ours earlier this week and plan to retrofit it on to our low cost version.
Ours was 1106.00 with shipping. :roll_eyes:

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Sheesh! You had to buy it? One of our mentors says he can do it easily enough, he just needs to know exactly where it stops. He won’t tell how he’s going to do it, though. Must be a secret. :shushing_face:
The thing is, many of us scoured the manual and found nothing even mentioning spinning or rotation.

Any chance of good, close pictures of the mechanism?

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We used to buy 7 batteries a season where the shipping was $500 until we found a local vendor only recently. I dont think you want to see the shipping costs for what we buy. VEX Pro now doesnt offer ground shipping (slower air) anymore, as its all 2 day as the only option.

You mean the upper goal structure? sure, I can take a pic later when i’m in our playing field area. Unless someone else wants to post of pic of theirs first.

Specially the mechanism that controls the low rung rotation…
Thanks!

The other option is of course to go to a preseason event which is probably going to be much cheaper. I’m on 2869 and we host a preseason event with as accurate a field as possible so if any teams near the Long Island area wish to come, dm me for more details.

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Sorry, we didnt get that.

My first though about the reason it is free to rotate is that it potentially makes it easier for a robot that gets wedged under it to remove itself.

From what I can tell it has nothing to stop it from spinning continuously.

It should spin relatively easily since it is powder coating on polycarb. However with the multiple points of contact the exact alignment of the supporting structure will influence just how much friction there is. It will vary from event to event and could vary throughout the event as contact is made with the truss structure, or weight is applied and removed from it as part of normal match play.

As to why FIRST did it that way. I’ve got some speculation.

#1 and the most likely in my opinion is that was just the easy way to do it with the design of the support mechanism.

#2 and less likely is to make it easier for those teams that want to do the “ramming speed ramp and lock style climb”, while at the same time requiring them to have their balance perfect so that all wheels do make it off the ground.

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Field Drawings can be found here: https://firstfrc.blob.core.windows.net/frc2022/FieldAssets/2022FieldDrawings-RAPIDREACTSpecific.pdf
For the low bar specifically, the mounting brackets can be found on pages 47 and 48.

Regarding the rotation, there are 2 bolts that hold the low bar holder and low bar bracket together, and there is a through bolt on the rung to prevent the rung from sliding out of the brackets. That is where the rotation comes from, and why it is not full circle.

Note, I have not seen a full field in person, and this is just educated guessing.

We are making a hanger for off-season events. The FIRST version is far as I can tell is a 1.66 diameter pipe through a hole on each side I suppose you could do some math and get an estimate but the pipe spins freely, weight of the robot would be considered, the powder coat applied to the pipe would be considered. As far as I can tell if you were to grip onto the pipe and try to articulate the robot the pipe will move.

We ordered the Andy Mark upper hub. With just a little experimentation it doesn’t seem that the balls want to bounce out. The plexiglass has enough give to absorb some of the momentum from the ball and they tend to find their way to the bottom of the apparatus.

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In the kickoff video, around 45:20, it does look kind of like the bolts stop it from rotating in one direction, and it’s just described as “spins a little bit”. I’m not sure whether it actually spins freely all the way around, but it’s not like I’ve seen a real field myself either.