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It would have been awesome if that article had, at any point, explained what an electric axial flux motor was, and why anyone might want one.
by AndrewDucker 4mo ago
It would have been awesome if that article had, at any point, explained what an electric axial flux motor was, and why anyone might want one.
- LoganDark 4mo agoHere's a good video on it from my watch history: https://www.youtube.com/watch?v=dCO633KE7RA https://www.youtube.com/watch?v=dCO633KE7RA
- akie 4mo agoThis one gives a shorter more high level overview https://www.youtube.com/watch?v=B0CNZPenCb8 https://www.youtube.com/watch?v=B0CNZPenCb8
- LoganDark 4mo agoI would be careful about that video, it seems relatively "explaining this new amazing innovation that has no/negligible downsides (please invest in us)" rather than "explaining the practical pros & cons of this technology".
- BiteCode_dev 4mo agoThe AI voice is annoying, the content is as personal a a vanilla yogurt but the animation is clear.
- lwhi 4mo agoGreat video. I didn't know I was so interested in engine design before I watched it.
- kenanfyi 4mo ago“What“ might be a long answer, but why anyone might want one is to have increased torque density for the given volume and diameter. So they are thin motors where the generated flux is parallel to the shaft. And they are like the standard PMSMs where you apply the same driving algorithm from the inverter side to use them.
- interloxia 4mo agohttps://en.wikipedia.org/wiki/Axial_flux_motor https://en.wikipedia.org/wiki/Axial_flux_motor
- joe_mamba 4mo agoThanks for posting this. Axial flux motors aren't some new sci-fi invention. We've had them in gadgets for a long time like in the floppy drive example. This is just one of the first industrial scale implementations of high-torque applications.
- lucozade 4mo ago> Axial flux motors aren't some new sci-fi invention Indeed not. The first ever electric motor was an axial flux motor built by Michael Faraday in 1821. It's definitely not a new idea.
- DrBazza 4mo agoThe automotive part is interesting: https://en.wikipedia.org/wiki/Axial_flux_motor#Automotive https://en.wikipedia.org/wiki/Axial_flux_motor#Automotive > 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 296GTB, Lamborghini Revuelto, McLaren Artura 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] > In July 2025, YASA announced a prototype 550 kW (738 hp) 13.1 kg (29 lb) motor, equating to power density of 42 kW/kg, which the company claimed to be the highest ever achieved.[11] By contrast, the state of the art EV motor from Lucid Motors offers a 500 kW, 31.4-kg motor, or 16 kW/kg.[12] > The first application of these motors will be in the High Performance Mercedes‑AMG GT 4-Touring Coupe.[14]
- jorams 4mo agoIt's a bit buried, but it does: > In contrast to conventional radial flux motors, the electromagnetic flux in an axial flux motor runs parallel to the axis of rotation. The key components are arranged in a disc‑shaped layout: two rotors sandwich the stator from the left and right. This design enables an especially compact motor architecture, high power and torque density, and new freedoms in drivetrain packaging. In the new Mercedes‑AMG GT 4‑Door Coupe, the motor at the front axle is just under nine centimetres wide; the two motors at the rear axle each measure around eight centimetres in width. The three axial flux motors are integrated per axle into so‑called High Performance Electric Drive Units (HP.EDU), where they are combined with a compact input planetary gearbox in a single housing.
- creativeSlumber 4mo ago> The three axial flux motors are integrated per axle I wonder why they need tree motors per axle.
- roelschroeven 4mo agoIt's poorly worded. There aren't three motors per axle, there are three motors total: one on the front axle and two on the rear axle.
- DFHippie 4mo agoI got the impression that there were three motors altogether and they were integrated with the axles.
- manarth 4mo agoThe translation's a little woolly. For the AMG GT4 there will be 3 motors: two at the rear, and one at the front. My interpretation (and my German's pretty lousy) is that each motor is combined with a gear system in a single package, and they're calling the overall package (motor plus gears) a High Performance Electric Drive Unit (HP.EDU). The two rear motors will probably be independent, so no need for a mechanical rear diff (it'll be electronically controlled). There's no mention of a front diff, so it's unknown whether that's built into the front HP.EDU or is a separate mechanical diff).
- chinathrow 4mo agoClick "More" and scroll down: "In contrast to conventional radial flux motors, the electromagnetic flux in an axial flux motor runs parallel to the axis of rotation. The key components are arranged in a disc‑shaped layout: two rotors sandwich the stator from the left and right. This design enables an especially compact motor architecture, high power and torque density, and new freedoms in drivetrain packaging. In the new Mercedes‑AMG GT 4‑Door Coupe, the motor at the front axle is just under nine centimetres wide; the two motors at the rear axle each measure around eight centimetres in width. The three axial flux motors are integrated per axle into so‑called High Performance Electric Drive Units (HP.EDU), where they are combined with a compact input planetary gearbox in a single housing."
- swiftcoder 4mo agoThis is the same design that enables the PCB Stator Motors, right?
- utopiah 4mo ago"Advantages : A motor can be built upon any flat structure, such as a PCB, by adding coils and a bearing." https://en.wikipedia.org/wiki/Axial_flux_motor https://en.wikipedia.org/wiki/Axial_flux_motor with image of "A miniature DC brushless axial motor used in a Digital Data Storage drive, showing the integration with PCB construction techniques."
- klaff 4mo agoYes. If you have a laser printer, that windup sound you hear at the start of a job is the polygon mirror motor spinning up thousands of RPMs - those are PCB stator motors. As were VCR head motors.
- moffkalast 4mo agoFloppy disk drive motors, but for cars.
- giancarlostoro 4mo agoReally the kind of thing that should be earlier in an article about… that very thing the reader is wondering about, but maybe we arent the target audience?
- geremiiah 4mo agoIt's basically the V8 of electric motors. Different topology results in better power to weight ratio. From the outside they look pancake shaped.
- nelox 4mo agoI want a V12 or V16, thank you very much.
- WJW 4mo agoStick two of them together on the same axle then.
- engineer_22 4mo agoOne in every wheel
- rswail 4mo agoWhy do you need an axle? Put the engine and its transmission to the wheel mounted next to each wheel. No need for differentials etc, if they can work out a steering mechanism for each, then you've got 4WD with 4W steering. In the video there's talk of how you can use them as regenerative braking as well, so have that as part of the wheel structure. No axles, no differentials, independent suspension, electronically controlled power to each wheel, regenerative braking. Gonna be a fun decade or more of innovation coming.
- abc123abc123 4mo agohttps://backtothefuture.fandom.com/wiki/Flux_capacitor https://backtothefuture.fandom.com/wiki/Flux_capacitor .
- numpad0 4mo agoMost motors have N-S axis of magnets aligned tangential to the axis of rotation. Axial flux motors have N-S poles parallel to rotation. This allows motors to be thinner and wider as well as anyhow more lighter and sometimes easier made. Whether they make sense depends, it seems.
- stasomatic 4mo agoThis sounds straight out of an 89’s sci-fi flick. What time we get to live in!
- lsowen 4mo agoA very good YouTube video from Munroe Live (an engineering firm specializing in "design for manufacturing") explaining it: https://youtu.be/dCO633KE7RA https://youtu.be/dCO633KE7RA "Axial Flux Motors Explained" Edit: a video from them on this particular YASA tech being discussed : https://youtu.be/m507ryWhc6c https://youtu.be/m507ryWhc6c
- verminator468 4mo ago[dead]
- farx 4mo agoVisited Astrall Dynamics, a Chinese startup that builds quadrupeds with axial flux motors here in Shenzhen. Super cool to see the robots in actions, carrying 60kg of weight up over 20 flights of stairs quite rapidly. The high torque at the compact form factor was super impressive. As far as I understood they are more complex to manufacture, especially at scale.
- PxldLtd 4mo agoHere's a great Instructable on building one yourself, much better explanations in there. https://www.instructables.com/Designing-and-Building-an-Axial-Flux-Motor/ https://www.instructables.com/Designing-and-Building-an-Axia...
- dzhiurgis 4mo agoAs far as I understand it's so small and lightweight you can put one on each wheel and remove brakes and still save weight (something something unsprung weight bad).
- verminator468 4mo ago[dead]
- altairprime 4mo agoConsider the thousand or so comments at https://hn.algolia.com/?q=axial https://hn.algolia.com/?q=axial for more details. While it’s no substitute for a well-written comprehensive article, it certainly is a smorgasbord of answers.
- m463 4mo agoI was curious before reading the article and read this: https://en.wikipedia.org/wiki/Axial_flux_motor https://en.wikipedia.org/wiki/Axial_flux_motor