Cool stuff from gizmag

[unixronin]

• Internal combustion/steam hybrid from BMW -- The powertrain is retrofittable into existing vehicles, down to a 4-cylinder 3-series
• French company Osmos "reinvents the wheel" -- hubless "orbital" wheel offers numerous advantages, they claim
• Peugeot shows off two-seater electric "city car" concept -- you enter and leave through the center of the hubless wheels

Some of these may be old.  But they're still cool.

Comments

[juuro.livejournal.com]

I am not quite convinced of the dirt resistance of the Osmos wheel. The bearing is open to the environment, after all.

[smandal.livejournal.com]

Precisely, and the I'm skeptical about the reduced unsprung weight since the runner+brake surface is now of a wider diameter (at least, on a motorcycle).

Also on a motorcycle, you want the steering axis to be roughly coincident with the line passing through the center and contact patch. Otherwise, you'll understeer trying to "fall into" the turn as the swinging of the wheel competes with swinging the rest of the bike.

I'd like to see someone try the concept on a bike and get a test report.

[unixronin.livejournal.com]

I would think you can probably put the "virtual steering axis" pretty much wherever you want. You can probably even move it in a speed-sensitive manner.

[smandal.livejournal.com]

Yup, but the forks would have to be more radical than a straight shot from steering head to axle. Would have to go around, and be that much more fundamentally rigid.

But, I'm just a naysayer -- would love to see concept that approached the performance of a current sportbike.

[ilcylic.livejournal.com]

Rim mounted brake disks seem to work well on the Buell XB-12. The ring itself is of a larger diameter, but you only need one to get the stopping force.

As far as the rest of it... I guess it depends on how much your hubs weigh. Since most of the ones for motorcycles these days are aluminum, it seems like it'll be hard to beat that.

-Ogre

[unixronin.livejournal.com]

Actually, going back to this, the rim-mounted brake actually turns out to be a weight saving change, because although it's larger diameter, it's not MUCH larger diameter; and, mounted directly to the rim, it can be supported more rigidly, so it can be thinner -- plus the entire rotor carrier can be eliminated. On top of that, because the linear velocity for a given angular velocity is higher, you can get more braking effectiveness for a given size pad (though the downside is the pads heat up faster).

[unixronin.livejournal.com]

I agree, that does seem a weak point. I don't know what, if anything, they've done to address it; the article is short on details of that. (More diagrams of the wheel mechanism itself would be helpful.)

[ilcylic.livejournal.com]

Ahhhhhhhh. So that is how it is different from Billy Lane's hubless motorcycle designs.

His versions of this concept use an $8000 helicopter main rotor bearing. So, I hope these guys source some cheaper parts.

-Ogre