Interesting Video Explaining The World's First, Geared, Continuously Variable Transmission.

[RaisedByWolves]

Torque in an ICE is transmitted one crank at a time. The one way bearing aka sprag has been around for a very long time and is commonly found in automatic transmissions.

edit: From what I understood, the sprag was use in the bike transmission to allow the pedals to free wheel. It wouldn't be necessary in an automotive application and would in fact, prevent engine braking.

An interesting idea. Any concept can be scaled up to address increased power needs. Increasing power transmission efficiency by 10% is a laudable cause.

As designed it still needs them for the arms to reciprocate.

 

[extropic]

As designed it still needs them for the arms to reciprocate.

I think you are referring to the "free wheeling" of the small planet gears when not transferring torque. It's can be seen in the CAD simulation that each small planet gear rotates (free wheels) relative to the arm when not transferring torque.
The presenter didn't mention ratcheting or Sprag at those gears but he did say "free wheeling" and a Sprag clutch is the obvious choice.
Another thing that occurred to me is the noise that thing made at very low speeds. The acoustic issues for passenger car application would be nontrivial.

Regardless, it's a prototype of a device I've never seen before and I'm impressed by it's creation.
Automotive engineering has performed, essentially, miracles in the last hundred years.
If they don't embrace the development and implementation of a gear based CVT, maybe they can implement a CVT that is about the same price and as easy to change as a bad tire. Do current CVTs last longer than a set of tires?

Thanks for posting @Eddyde.

 

[RaisedByWolves]

I think you are referring to the "free wheeling" of the small planet gears when not transferring torque. It's can be seen in the CAD simulation that each small planet gear rotates (free wheels) relative to the arm when not transferring torque.
The presenter didn't mention ratcheting or Sprag at those gears but he did say "free wheeling" and a Sprag clutch is the obvious choice.
Another thing that occurred to me is the noise that thing made at very low speeds. The acoustic issues for passenger car application would be nontrivial.

Regardless, it's a prototype of a device I've never seen before and I'm impressed by it's creation.
Automotive engineering has performed, essentially, miracles in the last hundred years.
If they don't embrace the development and implementation of a gear based CVT, maybe they can implement a CVT that is about the same price and as easy to change as a bad tire. Do current CVTs last longer than a set of tires?

Thanks for posting @Eddyde.

@18:20 you can hear the ratcheting in the video. I thought he mentioned this (I watched it last week) but I may have just inferred this by the sound on camera.

 

[Eddyde]

I think you are referring to the "free wheeling" of the small planet gears when not transferring torque. It's can be seen in the CAD simulation that each small planet gear rotates (free wheels) relative to the arm when not transferring torque.
The presenter didn't mention ratcheting or Sprag at those gears but he did say "free wheeling" and a Sprag clutch is the obvious choice.
Another thing that occurred to me is the noise that thing made at very low speeds. The acoustic issues for passenger car application would be nontrivial.

Regardless, it's a prototype of a device I've never seen before and I'm impressed by it's creation.
Automotive engineering has performed, essentially, miracles in the last hundred years.
If they don't embrace the development and implementation of a gear based CVT, maybe they can implement a CVT that is about the same price and as easy to change as a bad tire. Do current CVTs last longer than a set of tires?

Thanks for posting @Eddyde.

I agree the planetary gears are free to turn and not "one way" or "sprag clutch". I think the action is kind of hard to get but if you look closely at the animation starting at 11:12 those gears are able to transmit the torque because of the angle that lever-gear is traveling in relation to the ring gear. Once the angle changes the gear is no longer transferring torque and allows the next gear to take over, thus the non working gears simply freewheel.

 

[Eddyde]

@18:20 you can hear the ratcheting in the video. I thought he mentioned this (I watched it last week) but I may have just inferred this by the sound on camera.

He explains it at 21:14

 

[RaisedByWolves]

He explains it at 21:14

I knew I wasn't imagining this, I just couldn't find it.

I've watched dozens of his videos, and while he does an excellent job of explaining things, he goes too slow for my level of ADD and I wind up losing focus sometimes.

Thanks for the assist.

 

[extropic]

I agree the planetary gears are free to turn and not "one way" or "sprag clutch". I think the action is kind of hard to get but if you look closely at the animation starting at 11:12 those gears are able to transmit the torque because of the angle that lever-gear is traveling in relation to the ring gear. Once the angle changes the gear is no longer transferring torque and allows the next gear to take over, thus the non working gears simply freewheel.

In the animation, starting at about 11:12, you can see that when each small planet gear, in sequence, is transmitting force to the ring gear (red dot), the small planet gear is not rotating relative to the arm. And, when each small planet gear, in sequence, is not transmitting force to the ring gear (no red dot), the small planet gear is rotating relative to the arm.

In the animation you can see that each small planet gear does not rotate clockwise relative to it's arm and each small planet gear does rotate counterclockwise relative to it's arm.

This action requires a one-way drive like a ratchet or Sprag.

 

[extropic]

@18:20 you can hear the ratcheting in the video. I thought he mentioned this (I watched it last week) but I may have just inferred this by the sound on camera.

That ratcheting is on the output shaft of the transmission for the purpose of being able to hold the pedals still. It's not the same, and has nothing to do with, the one way drive on the small planet gears.

 

[Eddyde]

In the animation, starting at about 11:12, you can see that when each small planet gear, in sequence, is transmitting force to the ring gear (red dot), the small planet gear is not rotating relative to the arm. And, when each small planet gear, in sequence, is not transmitting force to the ring gear (no red dot), the small planet gear is rotating relative to the arm.

In the animation you can see that each small planet gear does not rotate clockwise relative to it's arm and each small planet gear does rotate counterclockwise relative to it's arm.

This action requires a one-way drive like a ratchet or Sprag.

You are correct. I found this in the comments section on the YouTube page:

NOTE: One-way ratcheting/ motion is an essential feature of this transmission and not bicycle specific as I mentioned in the video. Wothout a one-way bearing or a ratchet or other similar mechanism the small planet gears would just roll back and forth on the ring gear leading to no output. This is something I should have emphasized more in the video.

I guess I was paying too much attention to the narration and not looking close enough at the action, duh...

 

[extropic]

You are correct. I found this in the comments section on the YouTube page:

NOTE: One-way ratcheting/ motion is an essential feature of this transmission and not bicycle specific as I mentioned in the video. Wothout a one-way bearing or a ratchet or other similar mechanism the small planet gears would just roll back and forth on the ring gear leading to no output. This is something I should have emphasized more in the video.

I guess I was paying too much attention to the narration and not looking close enough at the action, duh...

I guess I'm sort of the opposite. I was watching the animation so intently, I had to replay to listen to the complete narration.
I don't yet have a clear idea of how the ratio change is accomplished. I haven't connected the dots between the motor driven screw and the three arm pivot centers being moved in the larger planet gears. I caught a glimpse of what I thought was a bell crank looking part but I haven't figured out how that effects changing all three offsets and keeping them precisely equal. It's a very interesting mechanism.
Wouldn't it be a cool project to make a working model? Too bad I already have more projects than I can ever complete. LOL
I almost never read Youtube comments because they seem to mostly be effusive praise. A "like" is sufficient IMO.