Want to see some wildly skillful LEGO construction? Check out [Banana Gear Studios]’ omni-directional treadmill which showcases not only how such a thing works, but demonstrates some pretty impressive problem solving in the process. Construction was far from straightforward!
In principle the treadmill works by placing an object on a bed of identical, rotating discs. By tilting the discs, one controls which edge is in contact with the object, which in turn controls the direction the object moves. While the concept is straightforward, the implementation is a wee bit more complex. LEGO pieces offer a rich variety of mechanical functions, but even so, making a 9×9 array of discs all rotate in unison turns out to be a nontrivial problem to solve. Gears alone are not the answer, because the shafts in such a dense array are a bit too close for LEGO gears to play nicely.
The solution? Break it down into 3×3 self-contained chunks, and build out vertically with gimbals to take up the slack for gearing. Use small elastic bands to transfer power between neighbors, then copy and paste the modular 3×3 design a few times to create the full 9×9 grid. After that it’s just a matter of providing a means of tilting the discs — which has its own challenges — and the build is complete.
Check out the video below to see the whole process, which is very nicely narrated and illustrates the design challenges beautifully. You may see some similarities to Disney’s own 360° treadmill, but as [Banana Gear Studios] points out, it is a technically different implementation and therefore not covered by Disney’s patent. In an ideal world no one would worry about getting sued by Disney over an educational LEGO project posted on YouTube, but perhaps one can’t be too careful.
It’s interesting but calling it a treadmill is problematic as there is no tread component. It is however, definitely a conveyor system.
its named treadmill after the verb tread, not the noun., like when you use it you are treading.
In that case, in order for it to be a treadmill then something would need to tread on it. The blocks are clearly not treading anywhere. Finally, the term is clearly not being used metaphorically so the logical conclusion is that it is a misnomer.
Per my suggestion, conveyor system fits much better as it is conveying the blocks.
It’s named this because that’s what a full scale system that was built recently is called. This is his recreation of the concept in lego. Shows the opperating principle well.
The application for these is a 2d treadmill for vr applications, so using the term ‘tread’ is appropriate
This is a copy of larger, “real” omni-directional treadmills being designed for things like VR. Sure, you can’t actually walk on this one — but you can’t exactly take a LEGO Space Shuttle to space either.
Coming soon: holodecks!
One improvement that can be made is to move the bottom part instead of the top. Now the objects are moved even when the motor is off.
Strange AI voice…