I was curious how this thing works and asked Claude to visualize it -- mostly to see how good Fable is and I have to say, what it made was good enough for me to get a gist of it. Posted it here
Every plausibly cool electric car innovation leads me to the same thought: “5-10 years from now, the restomod potential will be wild once these come down in cost.” For this, I am imagining retrofitting a Pontiac Fiero to reduce as much weight as possible and see if extended flight becomes possible.
Thanks for sharing. I wish it was a bit more interactive especially when there are parameters, e.g. "Widen the disc and torque rises with diameter cubed" I wish there was a slider to see that effect and thus maybe why there might be a sweet spot.
Also I have "The Way Things Work" on my desk right now and can't help but wonder, could you adapt some of the pages of the book this way? It seems like exactly the kind of content that would benefit from such 3D (interactive) visual explainers.
Hundreds of examples of axial flux motors exist online. If you look at the visualization it shows the iron cores in a perpendicular orientation with the hub. This is correct, but loses so much of what makes these specific motors interesting. The angled nature of the grey cores and copper wrapping smoothes the transition between each magnetic field.
Basically it is a pretty version of a dumbed down partially incorrect answer. With a knowledgeable user it would be very good, but he has no idea he is wrong. I’m not sure what Dunning Kreguer with graphics should be called.
You don't. You didn't know before either. The difference is trust. How do you trust it as much as you do the hypothetical humans making such representations? That's up to you.
I think humans develop expertise and brand names and get called out when they make mistakes and if they are too wrong, their reputation is damaged.
This doesn’t seem to apply to AI for some reason. It keeps generating incorrect results after incorrect results, yet people continue to trust its output.
I am not an expert, but I do know some physics and I know how to read, and I’m pretty sure this is full of BS. Also it’s a really crappy visualization.
I wonder how developing electric motors compares to combustion engines. My hunch says that it’s the main reason the Chinese high-tech electronics industry was able to develop and iterate leading electric vehicles so fast.
When these hopefully go to the next generation Formula E cars, we’ll see some crazy improvements in cornering. The newest generation already has active 4WD. I imagine this can bring even better torque adjustment improvements.
According to wikipedia[1] the first industrial steam engine (1712) was invented almost 100 years before the invention of the steam locomotive (1804), arguably its greatest evolutionary feat.
> develop and iterate leading electric vehicles so fast.
How do you know this for a fact? Chinese press releases? You've driven one? Some auto blogger drove one?
After world war 2 Gorbachev or whoever visited the United States and during that trio visited a supermarket. He thought it was a facade, possibly, put on just for him, there's no way Americans are this prosperous (or whatever, this good at agriculture, farm equipment, etc)
Also do the race cars have 4 wheel drive, or all-wheel drive? I'm wagering all-wheel with "torque vectoring" and "Yaw control", like a Mitsubishi Lancer Evolution X.
I am somewhat confused at the intensity of pushback for the statement “leading electric vehicles.”
Chinese EVs are leading and that doesn’t necessarily mean being the best, most advanced vehicles. They are leading in value/pricing, and in many regions they are leading in sales.
BYD sells almost double the EV volume of Tesla globally as of December 2025. They are objectively leading in that respect.
I think the parent comment of yours made a good point (or at least adjacent to a good point) about China’s ability to enter the market: they can’t compete with 100 years of internal combustion engine development along with the vast parts supplier network of the West, but they can compete on battery chemistry, battery supply, motors, and the more vertically integrated EV space where automakers don’t need to depend on a huge network of parts suppliers like they did in the past.
I also think that a lot of pushback to the innovation that China is delivering is criticism that is stuck in the past. If you buy a Xiaomi car, it integrates perfectly with all your Xiaomi consumer devices. You can control your rice cooker or robot vacuum from your car’s integrated infotainment system. This type of approach was exactly what Apple was going to deliver before they abandoned their automotive project.
Or, you can buy a Mercedes and you’ll get a car with more precise handling and perfectly tuned driving characteristics. The infotainment system looks like Windows Vista.
Which side of the aisle do you think most consumers care about? I think most people buy into Xiaomi’s approach.
I wouldnt be so harsh even with chinese combustion engines, its at this point a meme that is just copy pasted because everybody says so, but without actual experience. People dont understand how China is 3x bigger than Europe and 4x bigger than US, the scale of that market is absurd and competition numerous and fierce.
I've had MG suv rented recently with just gasoline engine and it was fine. This comes from long term bmw driver, they are not on the exactly same level, but light years ahead from similarly prices ie french vehicles. Handling was fine too, probably the biggest shock for me, this is where french, italian etc are losing me (bmw effect). And they cost 1/3 of bmw.
Listening to the heads of the American and European car companies say the same and driving in them in china. I know that is different than personally disassembling one and reviewing it, but I am not sure the incentive for the other companies to say they have inferior products, unless it was a play for subsidies or deregulation of some form.
Personally I feel that the rest of the world continues to dramatically under estimate China’s progress and technological advancement at our own peril. Is there fluff and are their lots of untrue claims, of course, but that is certainly not something they have a monopoly on.
"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."
Really 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?
"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 with image of "A miniature DC brushless axial motor used in a Digital Data Storage drive, showing the integration with PCB construction techniques."
Now basically the only new principle involved is that instead of power being generated by the relative motion of conductors and fluxes, it is produced by the modial interaction of magneto-reluctance and capacitive diractance.
The original machine had a base plate of pre-famulated amulite surmounted by a malleable logarithmic casing in such a way that the two spurving bearings were in a direct line with the panametric fan. The latter consisted simply of six hydrocoptic marzlevanes, so fitted to the ambifacient lunar waneshaft that side fumbling was effectively prevented.
The main winding was of the normal lotus-o-delta type placed in panendermic semi-boloid slots of the stator, every seventh conductor being connected by a non-reversible tremie pipe to the differential girdle spring on the “up” end of the grammeters.
The turbo-encabulator has now reached a high level of development, and it’s being successfully used in the operation of novertrunnions. Moreover, whenever a forescent skor motion is required, it may also be employed in conjunction with a drawn reciprocation dingle arm, to reduce sinusoidal repleneration
A very good YouTube video from Munroe Live (an engineering firm specializing in "design for manufacturing") explaining it: https://youtu.be/dCO633KE7RA "Axial Flux Motors Explained"
Visited 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.
> 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.
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).
Kind of orthogonal. Traditional AWD and part-time 4WD systems are solutions to get power from a single motor to both the front and rear of a vehicle. AWD has a center differential to account for differences in front and rear driveshaft speeds when driving on high-traction surfaces. 4WD just locks the front and rear driveshaft rotation together, which is a simple and robust solution that only works on loose surfaces.
With separate front and rear electric motors, there's no center differential to worry about, and a sufficiently sophisticated motor control system can make it behave well on and off road.
I'm not sure that the traditional notion of traction control applies, given that there are three independent suppliers of power, so you don't necessarily need the mechanics of diffs and computer-controlled brakes to provide maximum traction.
What would it mean to "turn off" traction control in a car with independent motors per wheel? (OK this is a 3-motor/4-wheel scenario, but hypothetically…)
With software control and independent motors, we're likely to see increases in low-traction capability (for the right price-point and probably aimed at particular buyers)
“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.
Most 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.
Consider the thousand or so comments at 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.
Thanks 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.
I 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".
As 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).
Very cool. Good to see more axial flux motors in the wild - will be interesting to see if they become the new standard in future. With smaller material costs the cost to manufacture at scale could actually become lower than radial
I expect radial will still dominate for at least another decade or so outside of premium performance focused cars. Radial has been battle-tested and proven. Axial still has a few more years to prove it's reliability in the field. Higher loads and stresses, tighter tolerances could make the axial motors less reliable overall especially at mass market trims. Mercedes is probably over-engineering for reliability and performance on the premium car
Radial is also "good enough" for most applications. The efficiency, form factor and weight improvements of axial is nice, but they aren't the limiting factor. Radial is already highly efficient, reasonably light and small. The real level for weight is the battery
I remember when YASA announced it and when MB bought them. Amazing technology and advancement in electric motor design. Good to see they somehow try to commercialize it.
An interesting part here is probably manufacturing and not the motor itself : going from a prototype to something you can mass produce reliably is often the hard part
Only slightly related but does anyone know anything about motors with magnetic bearings? As in, no contact or friction. I'm looking for a hardware project
Closest I can think of is flywheel "battery" storage tech many of which do have magnetic bearings and also some way to get power in and out of the flywheel so basically a motor. It's not exactly what you're looking for but there's prior art out there.
All motors are generators. It's only a matter of how you are creating the magnetic field with the stator windings.
In order to generate a higher regen, you'd have to somehow get more energy in the motor first... and since its only rated for 200kW, good ol' physics limits you, IF thats all the energy you put into the system.
If you roll it down a hill, or do something exotic like inverting the magnetic fields .... you can exceed the motor rating. But thats usually not recommended because the motor driver itself isnt rated to handle that power.
> can a car with 200kW propulsion have a 400kW regen
At the motor level it should be the same, in propulsion you’re converting current to torque and in regen you’re converting torque to current, with the same hardware. The high voltage wiring is the same and will set the same limit on current regardless of direction.
I believe bidirectional inverters are generally symmetrical as well, so that should not be a factor.
Which I reckon leaves two factors:
1. Battery C rates, afaik pretty much all chemistries have a higher discharge rate than charge rate, especially when trying to maintain them for a long time, so by that account regen power would at most be the same as propulsion (if the entire power train is sized for the battery’s charging rate).
2. Artificial limitations, obviously you could always artificially under-prop, though that seems unlikely outside of niche applications.
tldr: I don’t think so, except on a technicality (that you can artificially hobble propulsion).
How far fetched is the idea to use Super-Capacitors to take up the energy generated by braking and then slowly feeding it to the battery at a rate that it supports?
The energy density on super capacitors is pretty bad. If you imagine full power 200kW braking for 5 seconds that's 1 mega joule and at a best case 8 watt hours per liter you're going to need 35 liters minimum. Really you probably need to double that so you can float up and down and never fully saturate the capacitor as power inflow is going to drop as you get closer and closer to fully charged.
Am I reading you right that breaking power (that you want to regenerate in the system) >> speeding power? Obvious now I come to think of it, and still pretty nifty new thing learned if true!
Four years ago, when YASA's invention was discussed on HN, it attracted very little interest. Mercedes apparently saw more potential and decided to invest.
Probably not. A huge disadvantage of axial flux motors is they have a large number of poles, which means that they get less efficient at high speed because they require say 5x as much switching.
This makes them kind of unsuitable for power generation and really high power motors (despite their power density) where the main way you get more power is just to spin really fast.
The other disadvantage is they have such a low amount of material in them, that the stator overheats really easily. And the topology of the motor makes it really difficult to get the heat out efficiently, which again limits their maximum power.
For a century Germany's comparative advantage has been [mechanical] engineering. As a European I want (need?) Germany to succeed. Ergo: more of this, please.
Their advantage was mechanical engineering. They have historically not done well with electrical systems. So this is a change - hopefully for the better.
I am speculating but here might be reasons axial flux motors have advantage over radial flux motors:
1) torque: torque = applied force x length of the lever. Because the radial flux rotor must fit inside the stator, therefore radius << motor outside diameter. With the axial flux motor, the rotor is adjacent to the stator, therefore radius < motor outside diameter. Axial rotor radius > radial rotor radius.
2) space efficiency: in a radial flux motor you have 1 rotor, the coils arranged so that one end of the coil's magnetic field is useful to work on the rotor, the other end is not used. In an axial flux motor, (1) pancake rotor at each end of the coils, total (2) rotors, the coils can act on a rotor at each end. There is no free lunch here, to do useful work you still must provide more energy to the coil, but you can get the most from the space.
There must be someone here with a better handle on the electromagnetism, please correct me where I err.
Ah, another fantastic British innovator (YASA) having to realize its potential (and ultimately the downstream economic benefits of commercialisation) abroad.
Brought to you by the only country to have a space programme and abandon it.
Britain didn't abandon it's space programme. It abandoned a launch rocket programme though. That was over 50 years ago and the rocket was less capable and more expensive than alternatives at the time.
What alternatives? By your logic only one country should have a launch rocket. Thankfully that’s not a world we live in because that makes no sense. But I’m happy for you if you can be content with a space programme without a rocket, that’s a nice low bar to live with, you can basically never miss.
Did they have to? My impression is British companies sell out as soon as they can these days. Is this something that could be changed with policy? Does Germany incentivise running companies more? Or is this cultural, e.g. British people are more risk averse?
It's very difficult to raise late stage capital in the UK, especially for deep tech. We invent so much but our capital ecosystem is all tied up in land and our pensions providers don't want to know.
> UK is by far the best country to raise venture capital in Europe
For late stage? Continental Europe has its banks and industrial policy. America and China have their deep pockets. Scaling out of the UK is incredibly hard, doubly so post Brexit, that’s why they sell early.
I think continental Europe has nothing on the UK when it comes to banks and financial markets. The UK has the deepest pockets in Europe because it is a hub for global capital. Brexit does not seem to have made a difference:
UK has City of London that dwarfs the banks of continental Europe. we're talking big banks, Fintech, HFT, etc. When you deal with Austrian banks you realize they're 10-20 years behind the UK.
> and industrial policy
Continental Europe has a large but somewhat inefficient(compared to Asia) and heavily subsidized industrial policy, acting more a a jobs program for politicians chasing votes and state subsidies, that the UK gave up on during Thatcher(for better and worse), and stayed in the niche, low volume but highly important aerospace and defense parts that dwarfs that of continental Europe.
Ofc that also means the labor market in UK is very K-shaped. Highly paid skilled niche jobs in London and the university research centers, and then a wasteland everywhere else.
I think Germany has tax rules that make exits harder, whereas it's very easy in the UK to sell. If you have a more free market next to protective ones it makes sense that your IP is going to flow in that direction.
It’s cultural. It is not difficult to raise a lot of money in the UK. The problem is that the UK (government, investors, employees and employers) got so high on the margins of services and finance in the 90s, that it has never recovered from this all-consuming addiction. Everything else simply attracts no interest comparatively, economic diversification be damned.
I mean in EV's, a fancy expensive concept motor isn't going to help, autonomy should have been their direction 10 years ago, they are on the downward slope of their existence im afraid. Its the equivalent of Blockbuster adding a tape rewinding service to try and boost sales vs Netflix streaming.
That is also not guaranteed. VW (with its array of brands) leads the european BEV market by a lot. [1] (sorry I only found data for April 2026 right now but earlier months were similar)
One additional point of data. In Q1 of this year they delivered 200K BEV worldwide [2] while Tesla did 350k [3].
Calling that 10 years behind is not warranted in my opinion. I would agree to say competitive and challenged.
Never become dependent on doing hideously complicated things. You will eventually struggle to choose to do something more efficient, as the european auto industry is currently displaying. The car where thid motor will be used will, given current market sentiment, be a massive flop. Here they are showing off how complex the manufacturing process is. Surely we’d all be better off with simpler and cheaper processes.
This entire product is easier to build than the existing technology, has more simple tooling and will be simpler and cheaper.
Designing the manufacturing machinery is exactly what happens in any manufacturing process. Those robots are general purpose that have been adapted for the required tasks, that's a normal process.
Why would you build a motor that's twice as heavy with copper and much wider when you don't need to?
Efficiency and cost savings at scale usually involve an increase in complexity: in mass manufacturing, complexity is generally a fixed cost and so can be amortized over larger volumes.
By that logic we should all just be writing assembly manually. Screw hideously complicated higher level languages. Screw LLMs in particular, so complicated!
> Never become dependent on doing hideously complicated things
Is Mercedes stupid?
How did Carl Benz dare to do something as hideously complicated as building the first gasoline-powered car in history?
And why did they kept inventing complicated stuff that ended in all modern cars like ABS, adaptive cruise control, direct fuel injection, emergency brake assist, etc, etc?
Not all of those inventions are bad. But not all of them are coming from a place of necessity. All of them do increase complexity. My gripe with Mercedes is not that they are constantly pushing boundaries on what can be done with more tech. My main gripe is that the EVs they are building are essentially as complex as the ICE cars and follow largely the same design principles as the ICE cars. For instance, in the EQS, instead of applying engine breaking when the driver takes their foot off the pedal, they went to great lengths to _move the break pedal_ in proportion to the amount of engine breaking that is currently being applied as per the VCUs command. And yet the door cards on the EQS are not up to the standard of an S class.
My main gripe with MB is that they have this new technology that could simplify things and let them build a better product. Instead of building around it, they shove it in to their existing designs. I was expecting an electric S class to be more akin to a Lucid Air sans the teething problems of a new company. Instead, we get weak attempts at solving non issues.
And whilst they are certainly not in the market of producing affordable vehicles, I would hope that using EV tech they could create a better version of their existing fleet. I do not think anyone buying an A class cares about the 4 popper under the hood - losing it and simplifying radically, in my mind at least, would give them more budget and leeway to create a more compelling product.
> "instead of applying engine breaking when the driver takes their foot off the pedal, they went to great lengths to _move the break pedal_ in proportion to the amount of engine breaking that is currently being applied as per the VCUs command"
Regenerative braking slows the car more aggressively than an ICE where you take your foot of the gas, so the pedal change isn't putting on the brakes, it's communicating to a driver used to ICE that the car is slowing more than might be expected.
There may also be a sports-related reason for people who habitually left-foot brake.
It depends how much you draw from the motor/generator. One can modulate it as they want, whatever can't go into the battery due to chemistry or drive constraints can be disposed of as heat.
You clearly have never used a car like that. You develop muscle memory for where the pedal is - finding that the pedal is not where it used to be does not inspire much confidence.
Every other manufacturer has managed to control regen breaking via throttle modulation - even ICE hybrid cars have been doing that for ages.
I've used left-foot-braking in my (ICE-powered) daily driver for years.
Regenerative braking is very different to taking your foot off the accelerator in a conventional ICE car, it's much more powerful a stopping force than traditional engine-braking.
I understand the rationale for moving the pedal to illustrate the amount of "braking" force. I'll admit I'm not exactly a typical driver though.
The equilibrium of "good enough vs technological simplicity" for cars was probably reached in the 1950s. Everything after that was more or less solving "non-issues" with ever-increasing complexity ;)
Great, they finally started mass-producing 19th century technology, let's cheer that! Nowadays, while Chinese and Americans are producing GPUs, AI and li-ion batteries, German high-tech is an engine invented by Faraday
Here is a nice video that explains axial flux motors with a factory visit
https://youtu.be/B2Hl4c1iZK0?si=VfDYARyuaPVj1nKm
They are so, so, small.
https://azimi.me/axial-flux-motor-explainer/
Also I have "The Way Things Work" on my desk right now and can't help but wonder, could you adapt some of the pages of the book this way? It seems like exactly the kind of content that would benefit from such 3D (interactive) visual explainers.
The visuals didn't show much, and I learnt a lot more from one of the YouTube videos (https://www.youtube.com/watch?v=dCO633KE7RA) posted below.
It's neat that a whole interactive deck can be produced without effort. But it's just not very interesting.
What did you like most about it?
Basically it is a pretty version of a dumbed down partially incorrect answer. With a knowledgeable user it would be very good, but he has no idea he is wrong. I’m not sure what Dunning Kreguer with graphics should be called.
This doesn’t seem to apply to AI for some reason. It keeps generating incorrect results after incorrect results, yet people continue to trust its output.
I don’t know what to make of this.
When these hopefully go to the next generation Formula E cars, we’ll see some crazy improvements in cornering. The newest generation already has active 4WD. I imagine this can bring even better torque adjustment improvements.
It's not like the Dawn of the steam engine
[1] https://en.wikipedia.org/wiki/History_of_the_steam_engine
How do you know this for a fact? Chinese press releases? You've driven one? Some auto blogger drove one?
After world war 2 Gorbachev or whoever visited the United States and during that trio visited a supermarket. He thought it was a facade, possibly, put on just for him, there's no way Americans are this prosperous (or whatever, this good at agriculture, farm equipment, etc)
Also do the race cars have 4 wheel drive, or all-wheel drive? I'm wagering all-wheel with "torque vectoring" and "Yaw control", like a Mitsubishi Lancer Evolution X.
Chinese EVs are leading and that doesn’t necessarily mean being the best, most advanced vehicles. They are leading in value/pricing, and in many regions they are leading in sales.
BYD sells almost double the EV volume of Tesla globally as of December 2025. They are objectively leading in that respect.
I think the parent comment of yours made a good point (or at least adjacent to a good point) about China’s ability to enter the market: they can’t compete with 100 years of internal combustion engine development along with the vast parts supplier network of the West, but they can compete on battery chemistry, battery supply, motors, and the more vertically integrated EV space where automakers don’t need to depend on a huge network of parts suppliers like they did in the past.
I also think that a lot of pushback to the innovation that China is delivering is criticism that is stuck in the past. If you buy a Xiaomi car, it integrates perfectly with all your Xiaomi consumer devices. You can control your rice cooker or robot vacuum from your car’s integrated infotainment system. This type of approach was exactly what Apple was going to deliver before they abandoned their automotive project.
Or, you can buy a Mercedes and you’ll get a car with more precise handling and perfectly tuned driving characteristics. The infotainment system looks like Windows Vista.
Which side of the aisle do you think most consumers care about? I think most people buy into Xiaomi’s approach.
I've had MG suv rented recently with just gasoline engine and it was fine. This comes from long term bmw driver, they are not on the exactly same level, but light years ahead from similarly prices ie french vehicles. Handling was fine too, probably the biggest shock for me, this is where french, italian etc are losing me (bmw effect). And they cost 1/3 of bmw.
Personally I feel that the rest of the world continues to dramatically under estimate China’s progress and technological advancement at our own peril. Is there fluff and are their lots of untrue claims, of course, but that is certainly not something they have a monopoly on.
Edit.... Video doesn't seem to explain very well either
"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."
Hand waving.
The original machine had a base plate of pre-famulated amulite surmounted by a malleable logarithmic casing in such a way that the two spurving bearings were in a direct line with the panametric fan. The latter consisted simply of six hydrocoptic marzlevanes, so fitted to the ambifacient lunar waneshaft that side fumbling was effectively prevented.
The main winding was of the normal lotus-o-delta type placed in panendermic semi-boloid slots of the stator, every seventh conductor being connected by a non-reversible tremie pipe to the differential girdle spring on the “up” end of the grammeters.
The turbo-encabulator has now reached a high level of development, and it’s being successfully used in the operation of novertrunnions. Moreover, whenever a forescent skor motion is required, it may also be employed in conjunction with a drawn reciprocation dingle arm, to reduce sinusoidal repleneration
Edit: a video from them on this particular YASA tech being discussed : https://youtu.be/m507ryWhc6c
> 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.
I wonder why they need tree motors per axle.
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).
With separate front and rear electric motors, there's no center differential to worry about, and a sufficiently sophisticated motor control system can make it behave well on and off road.
What would it mean to "turn off" traction control in a car with independent motors per wheel? (OK this is a 3-motor/4-wheel scenario, but hypothetically…)
With software control and independent motors, we're likely to see increases in low-traction capability (for the right price-point and probably aimed at particular buyers)
https://www.instructables.com/Designing-and-Building-an-Axia...
https://en.wikipedia.org/wiki/British_Racing_Motors_V16
https://en.wikipedia.org/wiki/VR5_engine
We owned an vw inline 5 Passat (quantum in North America). Good engine and synchro awd.
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.
I expect radial will still dominate for at least another decade or so outside of premium performance focused cars. Radial has been battle-tested and proven. Axial still has a few more years to prove it's reliability in the field. Higher loads and stresses, tighter tolerances could make the axial motors less reliable overall especially at mass market trims. Mercedes is probably over-engineering for reliability and performance on the premium car
Radial is also "good enough" for most applications. The efficiency, form factor and weight improvements of axial is nice, but they aren't the limiting factor. Radial is already highly efficient, reasonably light and small. The real level for weight is the battery
Amazing what materials science achieving to get this sort of power as well as the engineering and manufacturing.
https://www.youtube.com/watch?v=dCO633KE7RA
For example, can a car with 200kW propulsion have a 400kW regen (Tesla has upto 65) and are cost effective like friction brakes?
In order to generate a higher regen, you'd have to somehow get more energy in the motor first... and since its only rated for 200kW, good ol' physics limits you, IF thats all the energy you put into the system.
If you roll it down a hill, or do something exotic like inverting the magnetic fields .... you can exceed the motor rating. But thats usually not recommended because the motor driver itself isnt rated to handle that power.
At the motor level it should be the same, in propulsion you’re converting current to torque and in regen you’re converting torque to current, with the same hardware. The high voltage wiring is the same and will set the same limit on current regardless of direction.
I believe bidirectional inverters are generally symmetrical as well, so that should not be a factor.
Which I reckon leaves two factors:
1. Battery C rates, afaik pretty much all chemistries have a higher discharge rate than charge rate, especially when trying to maintain them for a long time, so by that account regen power would at most be the same as propulsion (if the entire power train is sized for the battery’s charging rate).
2. Artificial limitations, obviously you could always artificially under-prop, though that seems unlikely outside of niche applications.
tldr: I don’t think so, except on a technicality (that you can artificially hobble propulsion).
https://en.wikipedia.org/wiki/Supercapacitor
https://news.ycombinator.com/item?id=31701133 Inside Yasa: how a British firm is revolutionising electric cars (2 points | 0 comments)
Personally I’d love to see this make it’s way into power tools and CNC motors.
This makes them kind of unsuitable for power generation and really high power motors (despite their power density) where the main way you get more power is just to spin really fast.
The other disadvantage is they have such a low amount of material in them, that the stator overheats really easily. And the topology of the motor makes it really difficult to get the heat out efficiently, which again limits their maximum power.
For example Siemens and Bosch are large enterprises specialised in industrial scale electrical machines and parts (among other fields).
Infineon was spun off from Siemens 25 years ago an plays an important role in chip manufacturing for automative systems.
1) torque: torque = applied force x length of the lever. Because the radial flux rotor must fit inside the stator, therefore radius << motor outside diameter. With the axial flux motor, the rotor is adjacent to the stator, therefore radius < motor outside diameter. Axial rotor radius > radial rotor radius.
2) space efficiency: in a radial flux motor you have 1 rotor, the coils arranged so that one end of the coil's magnetic field is useful to work on the rotor, the other end is not used. In an axial flux motor, (1) pancake rotor at each end of the coils, total (2) rotors, the coils can act on a rotor at each end. There is no free lunch here, to do useful work you still must provide more energy to the coil, but you can get the most from the space.
There must be someone here with a better handle on the electromagnetism, please correct me where I err.
If you’re not caught up https://youtu.be/m507ryWhc6c?si=Hq3dfjXYxEIlYzeo
Brought to you by the only country to have a space programme and abandon it.
I mean, so did France; they both essentially folded theirs into ESA.
For late stage? Continental Europe has its banks and industrial policy. America and China have their deep pockets. Scaling out of the UK is incredibly hard, doubly so post Brexit, that’s why they sell early.
https://www.uktech.news/funding/late-stage-funding-surges-as...
Regarding AI (since that's the hot thing of the day), but IMO indicator of where the money is:
https://digital-strategy.ec.europa.eu/en/library/funding-ai-...
[In the EU] "Most late-stage capital comes from the US and UK."
Now, regarding YASA, it isn't surprising that they were acquired by a car manufacturer. And, well, the UK has virtually none at this point...
UK has City of London that dwarfs the banks of continental Europe. we're talking big banks, Fintech, HFT, etc. When you deal with Austrian banks you realize they're 10-20 years behind the UK.
> and industrial policy
Continental Europe has a large but somewhat inefficient(compared to Asia) and heavily subsidized industrial policy, acting more a a jobs program for politicians chasing votes and state subsidies, that the UK gave up on during Thatcher(for better and worse), and stayed in the niche, low volume but highly important aerospace and defense parts that dwarfs that of continental Europe.
Ofc that also means the labor market in UK is very K-shaped. Highly paid skilled niche jobs in London and the university research centers, and then a wasteland everywhere else.
https://spectrum.ieee.org/axial-flux-motor-yasa
One additional point of data. In Q1 of this year they delivered 200K BEV worldwide [2] while Tesla did 350k [3].
Calling that 10 years behind is not warranted in my opinion. I would agree to say competitive and challenged.
[1] https://cleantechnica.com/2026/06/01/europe-ev-sales-report-... [2] https://www.volkswagen-group.com/de/pressemitteilungen/volks... [3] https://ir.tesla.com/press-release/tesla-first-quarter-2026-...
Designing the manufacturing machinery is exactly what happens in any manufacturing process. Those robots are general purpose that have been adapted for the required tasks, that's a normal process.
Why would you build a motor that's twice as heavy with copper and much wider when you don't need to?
What is the current market sentiment? Share of EVs is slowly rising so having a good motor as important as ever.
Is Mercedes stupid?
How did Carl Benz dare to do something as hideously complicated as building the first gasoline-powered car in history?
And why did they kept inventing complicated stuff that ended in all modern cars like ABS, adaptive cruise control, direct fuel injection, emergency brake assist, etc, etc?
My main gripe with MB is that they have this new technology that could simplify things and let them build a better product. Instead of building around it, they shove it in to their existing designs. I was expecting an electric S class to be more akin to a Lucid Air sans the teething problems of a new company. Instead, we get weak attempts at solving non issues.
And whilst they are certainly not in the market of producing affordable vehicles, I would hope that using EV tech they could create a better version of their existing fleet. I do not think anyone buying an A class cares about the 4 popper under the hood - losing it and simplifying radically, in my mind at least, would give them more budget and leeway to create a more compelling product.
There may also be a sports-related reason for people who habitually left-foot brake.
Every other manufacturer has managed to control regen breaking via throttle modulation - even ICE hybrid cars have been doing that for ages.
Regenerative braking is very different to taking your foot off the accelerator in a conventional ICE car, it's much more powerful a stopping force than traditional engine-braking.
I understand the rationale for moving the pedal to illustrate the amount of "braking" force. I'll admit I'm not exactly a typical driver though.
https://de.wikipedia.org/wiki/Datei:Wiesloch_Stadtapotheke_E...