Hacker News Reader

Comment by impossiblefork | Hacker News Reader

I sort of wonder how well these things can be scaled down.

Wheel hub motors are obviously bad, for harshness reasons, but if you could have a motor like this weighing 1-2 kg, and put one on each wheel, that'd be okay.

Power-wise this would be okay if things are linear. 26 kW per wheel sustained power output is more than enough for a light car. The question is what torque a scaled-down machine can be expected to have.

View on HN

I'm wondering if it would make sense to integrate the rim, motor and wheel bearing into a single assembly to save weight and cost. That combined with the weight and packaging benefits of not having half shafts and differentials might make it worth it. Plus there can be additional benefits, like the extra maneuverability that ZF Easy Turn and Hyundai's e-Corner have demonstrated.

30kW sustained/60 kW per wheel peak power is easily enough even for large passenger vehicles. Sustained could take 3 ton vehicle up a 10% grade at 120 km/h.

Things like that do exist though. There's an expensive Renault with motors like this, there's also the MW Motors Luka.

MW Motors eventually made a version where the electric motors were moved from the wheel hubs to a more conventional arrangement, so presumably they felt that it was some sort of problem, but they still make the original version and I've never been in one, so I can't be sure.

Reply on news.ycombinator.com