448X, 21S, 6671X, and 1437Z RI3D Reveal

Do you have a rough estimation of when the documentary will be posted?


What is the ratio on the linkage that pushes the tray out?

I thought that was only for Turning Point, and that it wouldn’t carry over to future seasons?


It’s a 7:1 torque ratio on a 100RPM V5 motor.


We’re trying to get the documentary out soon. Jess, who is editing the documentary, has been on vacation and doesn’t have much access to the internet, so my rough estimate would be within the next couple of weeks hopefully.


Nice robot and all but that MUSIC IS DOPE. What’s the song’s name

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Thank you!

The song is the You and Me Flume Remix.


Without further ado, here is the documentary for the 448X, 21S, 6671X, and 1437Z RI3D. We hope this will give some more insight into the build process of this robot, the problems we ran into, and the reasoning behind the various decisions we made. We also put together a written documentation with some more details, which is linked below and in the video description. The link to the GitHub repository is below and in the video description as well. Again, feel free to ask any questions. Thanks!


Writeup: VEX 2019 Tower Takeover RI3D Documentation - Google Docs

GitHub repository: GitHub - Unionjackjz1/Goofy-RI3D


Great job guys!!
Gonna make sure my teams look at this documentary… there is so much that they can learn from it.

Think this might have the same effect as last season 574C puncher tutorial :slight_smile:


<Insert maniacal laughter here>


Based on what you learned from this bot do you think a one motor roller for a tray stacker would be viable?

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If you read the write up it says they were thinking about dropping the internal rpm from 200rpm to 100rpm so one motor could work but obviously not as well.

It of course depends on how many cubes you wish to intake and at what angle the tray is at. If you do a flip out like this design you wouldn’t be able to do a one motor intake anyways.

The biggest advantage of tray bots over lift bots, to me, is the quicc succ of cubes or cube pickup speed. A tray doesn’t have to stop to pickup a cube, it can continuously go straight and intake. With one motor at 100rpm you sacrifice that which doesn’t seem worth.


I keep having to restate this, but what exactly is making you guys think that a lift, tray, and roller intake cannot go together

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Oh it definitely can, too much effort to type out as well as kinda irrelevant to what I said?

1 motor roller intake would work for a lift with a tray but if you’re going to do a lift putting a tray on it doesn’t seem like the best option.

Watch me


i think i’m good :wink:

but seriously, it could definitely work well but I don’t see it being as efficient as a different lift style or a regular tray bot. Good luck tho, maybe I’m wrong and you’ll be mega op


I think that tray lifts will be irrelevant until a passive method of expanding their capacity is designed. You can’t reliably lift a tray with 8+ cubes, so you sacrifice a lot of time unless you have another way of holding more. However, if you used a passive intake, you have another motor at your disposal…

A tray lift can expand the same way a tray bot does. Im not saying they will be the meta, or that they will be ultra competitive. Im simply saying it is possible


Getting enough compression for the rollers to lift up cubes was one of the biggest challenges we experienced, and it is why the majority of the documentary discusses the issues we had and how we solved them. I think 1 motor rollers are possible, but I’m skeptical of their performance.


Lifting a tray is going to be very difficult. 6 cubes weigh the same as 1 mobile goal from ITZ, not counting the weight of the tray - they are very heavy!

In order to lift this many cubes, you’d need to gear the lift for torque. A motor breakdown for a bot like this could look like:

4m drive
2m lift
1m roller intake
1m tray tilter

You’d need to gear the lift for torque, which will slow it down. This might not be as big an impediment as it might seem though, as the lift only has to go up/down when you add to an existing stack.

Also note that a 1m intake, while certainly not impossible, is more difficult to build than a 2m intake.