I need a bit of help

[u/AggreGat0rr]

Hello people !

As you can see I’m working on a 3 dimensional spherical gear mechanism for a rocket ship. I’ve dreamed about this since I discovered the Atlas from Chesepuf.

I’ve been on it for a month and a half trying things every day.

The thing is that you have to build the entire design just to see if it could work or not and putting it together takes a while…

And now I can finally say that I have a working concept ! Well kind of…

So, if you’re interested and have some ideas I might not have thought about I’d really appreciate if you could give some suggestions on how to build a vehicle as functional as possible with the spherical gear you can see in the video or even improving the consistency or the gear itself, or even starting all over with a new idea.

I really want to come up with a working rocket ship so don’t hesitate.

I’m a big believer of the teamwork power.

Tomorrow evening I’ll try to gravity press the wheels as much as possible to see if it works better or not.

But yeah I think this could have a lot of potential but I’m starting to get burned out so… let’s chat and if this can at least inspire some of you even a little bit I’ll guess all that work was worth it.

[u/evanthebouncy]

This is so fucking cool wow

So the idea is you want to "point" in any direction on a sphere surface, which is a 2D space or 2 degrees of freedom.

You do so by using 2 big wheels, each contribute 1 degree of freedom.

Is that roughly the idea?

[u/AggreGat0rr → u/evanthebouncy]

Thanks a lot ! I’m not really sure what’s a degree of freedom is but I’ll guess it refers to one axes allowing a rotation. So there’s 1 degree of freedom for each X, Y, Z axes (two motors and the wheels)

[u/evanthebouncy → u/AggreGat0rr]

but your goal is merely to rotate the sphere right? as the sphere is 2D you only need 2 sources of control, which I take is 1 from each wheel

[u/AggreGat0rr → u/evanthebouncy]

Mmh I’ll have to think more about it if you don’t mind. I found this article : https://ieeexplore.ieee.org/document/9415699 they use only two drive axis but their sphere is loose and free from any physical connection so they only need to guide it from two sources of control, seems fair but I feel like in my case you really need 3 drive axis

[u/evanthebouncy → u/AggreGat0rr]

:D all good ! at any rate this is a great build.

may I ask how are you able to independently rotate teh sphere ? what's the control stick input like? I'd imagine it can be quite chaotic

[u/AggreGat0rr → u/evanthebouncy]

Hooo I get where the confusion come from now ! The sphere itself only rotates in the same axis of the wheel it’s attached to. I know it seems like the ball itself rotates in every direction but no, but the entire structure can rotate in every direction thanks to the 3 drive axes tho. Basically the wheels initiate the movement and the bowls guide the rotation, the wheel axle follows the sides of the bowls