DR4B vs Tray Stacker

People keep forcing the idea that you need a 2 motor intake. You do not need a 2 motor intake at all, there are plenty of work arounds for that. The biggest issue with a tray stacker and dr4b all in one combo is space efficiency, not motor distribution. Will there be enough room within a 18x18 robot? The answer is yes, but you really need to be conscientious and methodic about sizing. CAD is the best way to do that.


As a matter of fact, yes
No actually I’m trying to do it. If it succeeds then it will be game breaking. We’re talking 15+ cubes here


To be fair, though, you only need a stack height of 12-13 cubes to win as long as you keep towers neutral

15 cubes would probably fall. I doubt that would be a viable option considering there isn’t a weighted base to stack on like ITZ and the cubes are pretty slick. 15 cubes times 5.5 inches is 82.5 inches tall. Thats equivalent to 6.9 feet. A tower that tall would fall to a very slight vibration. So while you may set it down successfully it could just spontaneously collapse later in the match. I could be wrong, but I think focusing on stacks of 7-10 and playing your colors right will be the worlds winning strategy.


Yeah I’m not planning on stacking 15+ cubes in an actual match, but it could be done.
Just because u can doesn’t mean u should:D

Edit: I’m trying to do so, so my bot would have the ability to do so, but it wouldn’t be used in actual matches


I guess I can see that. Then if you ever have a slow or dull match you can try and drop a world record stack. That’d be fun.

I still think late season DR4B with 4-5 cube trays on th will be superior, but I could be wrong.


I’m betting someone’s gonna figure out how to combine the two. Maybe having something on top of the tray that can grab a cube off the top and place it on towers or other stacks. That’s my prediction anyway.

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My thought is that we will have the tray stackers we see now, but they will have a smaller capacity and the whole intake and tray will be lifted up on a DR4B.

I can see that being successful, but you’ll have to be smart about colors. Picking certain colors and scoring colors that you have more of and your opponent doesn’t have.


I’m optimistic about the idea of a tray on a DR4B, but there are some pretty important issues with it at the moment.

First of all, the tray and all the cubes on it will be very heavy. Even with an aluminum (or even a polycarbonate) tray, the weight of the cubes would be heavy enough that even lifting 4-5 of them would be a challenge.

Second, there aren’t very many motors. A tray requires 3 motors: one for the pivot, and two for the intake. A lift requires at least 2 motors (especially considering how much weight it’ll be lifting). A drivetrain needs at least 4. The solution would need some way to remove one of the motors.

Single-motor intakes are possible, but difficult. You would somehow have to route power behind the tray, as anything in front of it would get in the way of the cubes. Some system of bevel gears or long chains could be used, but this would add a lot of friction and drastically increase the mechanical complexity. Considering the amount of power the tray intake requires to push cubes up the tray, a one motor intake might not be powerful enough to pick up enough cubes, especially factoring in the added friction.

There generally aren’t massive, “game-changing” improvements like this late in the season. After the initial ideas are formed, it’s just iterative improvements. For instance, in Turning Point, we went from 100rpm punchers to 200rpm punchers. Double catapults just got their arcs tuned better to make Hyukapults. And yes, some teams worked a ton on crazy ratcheting mechanisms (like 315G) to put more functions on a single motor. But in general, very complicated mechanisms like a single-motor intake aren’t very prevalent Vex, even among the best of the best.

I’m not saying it won’t happen, but I just don’t see a tray-on-DR4B being a viable strategy.

(That being said, an alliance of a traybot and a DR4B reverse stacker would complement each other pretty well, just like how double catapults and punchers won Worlds…)


Actually if I remember right a double catapult and a flywheel won worlds, but a d catapult and a puncher/slapped took research and would have won if not for a dq so it was still a viable strategy.

Our team is also making a bot that can stack ridiculously high just for the option. We do intend to use it however, because we are opting to use rainbow strategy, and it’s much easier to just throw a couple of cubes on a high stack if we need more of one color to win than to replace cubes in a stack. This probably won’t happen very often, buts it’s one of those features you’re glad you have even if you only use it once.

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Guys, you don’t even have to stack them if you have a decent stack. The ability of holding 5 or more cubes at once means that’s 5 or more less cubes the other alliance has access to

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Yes, and to garuntee a win by hoarding those cubes, you need to have at 11 of 2 colors and 12 of a third unless you win auton, in which cas you should still aim for 10+ of each color so that towers don’ t become a threat. Should you get those stacks without a balance of colors, it is faster to just throw a couple cubes on top.


Maybe, but how do you plan to stabilize the stacks. I don’t think it’s possible to get a stack higher than eleven to not spontaneously crumble because someone bumped the wall. I just don’t think it will be practical.

When we got our game elements, we manually stacked 12 just to see how high it was, and our teammate, trying to be funny, whacked one of the middle cubes. To our surprise, the tower didn’t fall, despite half of the cubes being offset, and it didn’t fall until we knocked it over ourselves.

There haven’t even been any competitions in the United States yet. Waiting till we get a better idea on how we’ll both designs work should probably help differentiate the pros and cons.


Remember that the fields may not be perfectly level.


In the rare event of this actually being the case, you wouldn’t be able to stack that high anyway, let alone stack on top of it, but this problem would also affect your opponents, which would balance out the problem. I don’t think this will actually occur though, as I’ve never been to a competition where this was a problem.