Extending Reverse Stacker Idea

Reverse stacking is when you build your stack by putting cubes on the bottom. I want to do this for tower takeover game but it requires the stack of cubes to not fall over. I came up with an idea to reverse stack and passively hold the cube stack.

It uses a sort of back-plate that can extend freely. The back-plate gets pushed by the cubes in the stack. By mounting the whole mechanism at an angle one side can be open and allow the robot to deposit the cube stack quickly and easily.

Here is an animation to demonstrate the concept…

I am interested to hear your thoughts and ideas about this concept and how to improve it.


The one issue with this design that I see is, what would you do about opposing alliance robots pushing you and making you drop you stack of cubes.

Awesome animation. Friction at the top will be a problem, but a solvable one. Tipping is obviously a concern, and wow the forces at the hinge. Also finding a way to put stacks close together without knocking them over. None of that is impossible to deal with - you have a very solid idea and a great animation of the concept of reverse stacking. Good luck!


I see some potential issues with releasing, but a solid idea.

How will you pick up already stacked cubes? Seems like all this design needs is some sort of lift to raise it to put cubes in towers and pick up pre-stacked cubes.

I was thinking about a design like this, but with no access to the towers you wouldn’t be able to get a very high score. A design like this could probably get you a state qualification in the season’s earlier tournaments (September or before), but most likely wouldn’t be that effective at State.

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Releasing the stack with this design wouldn’t work because in order to intake the cubes, there must be enough traction between the rollers and the cubes, which would pull out the bottom cube which is touching the rollers when releasing the stack.

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A great animation, to demonstrate the investigation points to the concept of a new construction of the challenge!
Keep it up and discover the best solution for this new season!

Greetings from Brazil!

Always developing the best for the Robots! :robot::point_up:

great design. One thing that confuses me is the drop. How does the design let go of the stack?


looks pretty cool! what did you use to animate this?

2 possible ways to drop the stack - reverse the intake rollers so they slide down while you back up (sliding friction is much less than static friction). Or use omni wheels.


You could also have the side bars open and close, including the part with the rollers.

You could put the rollers on arms and then use a ratchet to make the arms open when you outake.

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thats a pretty cool design, pretty similar to what I’ve been working on, though, in the future, if you think something is good, I would recommend keeping it to yourself for as long as you can. An example is how 1104 won worlds (in nbn I think) by keeping their things secret. An example of what not to do is what a former Can did in that same season. He sold out the rob roller intake and it became the meta, taking one of his big advantages. Or at least thats what he told me.

The intaking of cubes and releasing them like in the animation isn’t actually possible because of the conveyor-belt intake but there are solutions like moving the intake or …

I think omni-wheels might be the better solution. That way the cubes could easily slide in.

Also a possibility might be moving the whole mechanism up and down to pick up stacks.

I used blender because I am good with it and it allows for complex animation.

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What if you made an inner carriage that slides out with the cubes/raising part, while the rollers stay behind in the chassis. Then you get get over the bar without driving, score two stacks next to each other goal area, and overcome the issue of ejecting the stack from the rollers.

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What animation software did you use?

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The community is slowly catching up to what I already have… But a bit askew.

Omni rollers are too heavy to use effectively, and there’s not a lot of space in those zones. You’d need to be able to lift up the whole intake with that design to deposit cubes, and on top of that, there’s no way to place in the towers.

That takes us back to the whole ITZ reverse internal stacker thing. It already has a built in lift to put cubes on top of already built stacks.


Knock them over!!!

Actually I see it as an extremely viable strategy, if another robot at the comp can reach the towers and they pick a robot like this the amount of points would be insane. If the qualify for states they would have a robot that can score really quickly and a lot of robots at state will likely be able to reach the towers which means during quals they would have insane scoring capabilities. On top of that you could easily power the entire mechanism on 2 motors if they chain the two sprockets together which means they could have a 6 motor drive.

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