Comment by jama211

6 days ago

I don’t see anything inside the article that says it’s designed to be inside the wheel. I’m not sure where they got that from.

From Wikipedia on Axial Flux Motors: >"Mercedes-Benz subsidiary YASA (Yokeless and Segmented Armature) makes AFMs that have powered various concept (Jaguar C-X75), prototype, and racing vehicles. It was also used in the Koenigsegg Regera, the Ferrari SF90 Stradale and S96GTB, Lamborghini Revuelto hybrid and the Lola-Drayson.[9] The company is investigating the potential for placing motors inside wheels, given that AFM's low mass does not excessively increase a vehicle's unsprung mass.[10] "

  • The fact that you CAN put it in the wheel doesn't mean it MUST to go in the wheel.

  • They’re investigating the potential for them to be placed inside wheels, but they aren’t at the moment, so my point stands.

I think they misspoke when they said "in" the wheel, but supercars can have a separate motor for each wheel, and the closer they are to the wheel the better the torque as it's not also driving a longer shaft. The smaller the motor, the closer you can get.

  • I guess if you can make the motor and a suitable reduction box lighter than the equivalent bearing and driveshaft combination you could make the suspension arms mechanically simpler.

    By using motors at each wheel you'd eliminate the need for a differential, saving a good 40-50kg or so. Of course, if you kept the drive shafts and put the motor and reduction box in the middle, you'd be able to use inboard brakes and save a lot of unsprung weight!

    • it would be really interesting if it became possible to do electronic only breaks. I'm sure the regulatory system isn't there yet, but it would let you shave a whole bunch more parts and complexity

I get your skepticism and I know nothing about the field, but if the round thing in the press release picture isn’t designed to fit in a wheel, I’m confused. https://yasa.com/news/yasa-smashes-own-unofficial-power-dens...