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Inception Drive: A Compact, Infinitely Variable Transmission for Robotics

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Re: Inception Drive: A Compact, Infinitely Variable Transmission for Robotics

#7

It is hard to believe it is really efficient seeing the description. I have driven cars with CVT and not been impressed.

FWIW, they're claiming the whole system (motor operating at optimal state point + IVT gearbox) is more efficient than the usual whole system (motor operating far from optimal state point due to size and weight constraints + fixed ratio gearbox). Which is not immediately implausible.

Re: Inception Drive: A Compact, Infinitely Variable Transmission for Robotics

#8
It almost looks like they combined a CVT and a planetary gear.

For those saying it has too many moving parts, consider the number of parts found in an 11-speed internally geared hub on a bicycle [1]

I would be really curious to see if this inception drive could be an alternative to internally geared bike hubs.

[1] https://www.sheldonbrown.com/alfine-11.html#details

Re: Inception Drive: A Compact, Infinitely Variable Transmission for Robotics

#9
This seems like the mechanism can be summarized as working by precession.

The inner pulley wobbles inside the flexible V-belt and is induced into rotating by precession.

Separation of the inner pulleys controls the effective precession cylinder's inner diameter, the variation of which is accomodated by flexing of the belt: how far it is "squeezed off" and displaced from its outer mount.

https://en.wikipedia.org/wiki/Precession_(mechanical)

Note in the precession animation here how the fast spinning green arrow can be regarded as an input (the wiggle), and the slow spinning of the square-centered blue wheel as an output: there is a many-to-one reduction here, effectively forming a transmission.

Not to be confused with: https://en.wikipedia.org/wiki/Precession

Re: Inception Drive: A Compact, Infinitely Variable Transmission for Robotics

#10

It's clever. But so many moving parts, and doesn't look very sturdy, nor efficient.

There was a device called an electric wheel, a few years ago, which did the continuously variable thing using a planetary gear (the sun and ring were driven by separate motors, and drive was taken from the planet carrier.)

http://web.archive.org/web/20080104094149/http://www.solomon...

This design is inherently more compact than that arrangement, and the parts are simpler. (I think)

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