@Onloop: to revive the question you asked a long time ago and partially answered, Stary confirmed what you postulated. I sketched it out, then asked in the Kickstarter questions. So yes, there are two barrels moving in opposite directions. The CAD graphic is accurate and not just an illustration. The tricky part was figuring out that the axle of the truck is “sawed off”; it ends in a squat ziggurat-shaped heatsink thing to which the carrier holding the planet gears are attached, and the stator is mounted to this.
The inner barrel is the rotor, and is connected by the hubcap to an axle (not the truck axle!) which goes through the stator and ends in the sun gear.
Pretty darn cool if you ask me. I didn’t get any answers on how they prevented collision between the spinning barrels (moving in opposite directions, as you said), and whether this gap needed lubrication. If you look closely, you’ll notice that the outer barrel has to be pretty damn rigid, since its contact surface with the transmission is only on the inner rim. The rest of the barrel “floats” - there seems to be no support or bearing on the outer side. Any materials people out there who could judge on how big a problem this might be? Even if the barrel is extremely resistant to deformation, urethane, and whatever is used to adhere the urethane to the barrel, is by definition not.
Would this give more traction on the inner lip and less towards the outer? If you look at the last video, this would seem to be the case: https://youtu.be/ShvdaRMiF2k?t=91 . Check out the difference in dirty/clean areas of the drive wheel compared to the front wheel.
@Sebastian The only “extra” info that backers would possess are some extra photos of parts in production: circuit bords of the remote, and some shots of the board that was thrown off a chimney. At this point, no one knows where they are with certification. They talk about a lot of 30 pre-production boards that will be used for testing, so we can assume they are not assembled yet either…this is gleaned from the KS questions page.