Air conditioning and touchscreens didn’t alter how cars drove but did revolutionize the driving experience.
Can we please make touchscreens for neccessary functionality illegal, like using phones while driving?
They also provide tactile feedback allowing you to be sure they have been pressed without even looking.
My parents’ Lexus has a button joystick kind of thing with similar resistance tech to the ps5 triggers for the navigation. It’s not bad.
The joystick is on the center console, so you can use it without looking.
I suppose the advantage on aircraft and spacecraft is that they consolidate functions so you don’t have to have 90,000 switches in the cockpit, half of which you won’t ever need.
Anything you need to find in an emergency absolutely should be a physical switch but anything else can probably be a UI interface.
But in the car you need to keep your eyes on the road at all times, which isn’t so much of a requirement in the air.
If you can consolidate the UI to make it with work with touchscreen, you can make it work with something like Keyboard + trackball mouse and you can get rid of that touchscreen. I know it’s not the same stake situation but have people forgotten how much functionality blackberry had with QWERTY and few more buttons. Shame that the company went out the way it did
I’m pretty sure they are for safety critical controls, such as in an aircraft cockpit. In the automotive world, we like to keep it jazzy and smooth, like my romantic life.
They aren’t. Light ircraft now use touchscreens that you are supposed to use while bouncing around. They had a knob for a while but then it seemed touchscreens took over. With the knob you still had to look, it at least you didn’t have to aim at a bouncing spot on the screen.
Can we have more mechanical posts like this?
No, you need 555 posts about the shit that a billionaire said about stuff he knows nothing about
There’s 2 significant inaccuracies in the article and 1 large oversight in the official video.
- Differentials are not one wheel drive. They can seem to drive only one wheel when spinning the wheels as one let’s loose and the other stays still, but it’s not driving one wheel. It’s still driving both. The problem is the free wheel is spinning at twice the speed indicated on the speedometer and the other is at 0. The driveshaft puts in a certain number of turns, the wheels, together, must add up to an equal output (multiplied by the gear ratio). If the car is going straight with full traction, then they turn the same. If you floor it in snow, one is probably spinning 40% over it’s share and the other 40% under. This is not unique to rwd either as fwd cars still very much have a functioning differential. To throw some numbers at it to help clarify the function, let’s say the engine is asking the wheels to spin at 30rpm each in a straight line. In a left turn, the right wheel travels further and needs to spin at 35rpm while the inner spins at 25rpm. It still adds up to 60rpm, same as a straight line. Mash it in the snow and it might be 60rpm in the left and 0nin the right or 0 in the left and 60 in the left. It could be 5/55, 40/20, or any other combo as long as it totals 60.
PS: differentials are irrelevant when the wheels aren’t connected to each other. Individual-motor wheels, as shown in the video, don’t need a diff. The non-drive wheels in a 2-wheel drive vehicle do not have a differential on the non-drive axle.
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Cv joints are not specific to fwd as nearly all modern rwd cars with independent rear suspensions have CV joints. I don’t know of any trucks still using U-joints either since big trucks are solid axle. Cv joints function the same as U joints. The difference is C.V. joints output constant velocity whereas U-joints (what you’ll see often under trucks on the driveshaft, two square C shaft ends with an X link between) have lopey output that gets worse with greater deflection angle. If you own a u-joint bit for your socket wrench, I invite you to play with it. Instead of a solid pinned X between the U ends, CVs have free-rolling balls that can roll inboard and outboard to maintain the link between the shaft’s cup and the wheel’s cone.
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The article is inaccurate but the video ignores this part, so I don’t fault The writer. The CV joints are said to be a poor design, yet, it ignores the part where the video reinstalls them at 4:20 and 5:10 for the front wheels. This mechanism does not allow angular deflection between the motor and hub, as it’s shown, without a CV joint. Lateral displacement, yes, but not angular - as in it can’t steer. This may be an overall improvement by reducing how often it needs to bend (only when steering), but it doesn’t eliminate it. And even then, the rear suspension is still designed to change camber as it changes ride height. Camber is the angle of the wheel as measured top to bottom, as in what you see from looking at the wheels from the front of the car. It keeps the wheels flat on the ground as you lean the car in a corner. You may see an overloaded car’s rear wheels look like /—\ as viewed from the rear or -–/ when hanging free on a lift.
Look, I’m not an engineer at Hyundai (or even a competitor) but this doesn’t quite pass the sniff test. Cool idea for sure, but it smells a little like marketing is clamoring for something edgy to display. Even as displayed, the motors and original reduces were already very compact and in close proximity to the wheels compared to a normal engine. The slightly reduced footprint of this uni wheel and slightly increased friction of a bunch of additional gears makes me think this is a fractional improvement in practice rather than a revolutionary improvement.
I’d be concerned with the amount of unsprung weight this adds, too. You’re basically taking the transmission and adding that mass to the hub. Seems like it would be pretty crashy on rough surfaces.
I considered that but couldn’t make any conclusions. The driveshaft and sun gear are not added to the unsprung. I’d guess only half the weight of planets and carriers is added. It definitely adds the weight of the ring gear to the unsprung mass.
I’m also curious how this affects rotational mass. So while every component spinning with the wheel from tire to motor shaft has rotational inertia, small-diameter components such as drive shafts have relatively little rotational inertia. Wheels and even brake discs have a lot more. I don’t have numbers obviously but I’m curious if the rotational mass of the ring gear ends up being detrimental compared to a heavier-weight lower-inertia cv setup.
Isn’t the ring gear the wheel body (or whatever it’s called), that is, even a fixed axle would have weight there, the gearteeth even provide stiffness. CV joints also contain unsprung mass, I’d say there might be a bit of a difference but nothing drastic. With modern fancy biomimetic wheel body geometries and everything you’ll probably definitely be lighter than 80s steel rims. What happened to spoked wheels, anyway.
Yep.
Trucks used these as far back as pre-WWII. It a great solution for off road vehicles to gain clearance. At low speeds, even universal joints work fine for this setup, because the shaft rotates at 1/3 wheel speed, like a drives haft does going into a differential.
This puts a diff at each wheel.
Edit: These are called Portal Gears
Not quite portal gears, that has the input shaft fixed at the top. This is like an adjustable portal gear.
I noticed they conveniently didn’t talk a lot about steering…
The claim of “one wheel drive” I think is meant to highlight what happens if traction is lost. It sounds like something I have heard on 4wd off-road forums. I agree the phrase “one wheel drive” is perhaps not a great way to explain the disadvantages of differentials vs limited slip differentials vs locking differentials vs individually driven wheels.
The idea of “one wheel drive” as I have seen it used, is that in a vehicle with one powered axle assembly (what we normally call 2wd-- either front or rear wheel drive) is that if you lose traction with either drive wheel, the vehicle no longer moves because all power is diverted to the slipping wheel.
If you have a limited slip differential, there is a limit to how much power is diverted to the slipping wheel. With a locking differential, you only stop moving if you lose traction to both drive wheels.
Anyway…
The design is really interesting.
You also bring up a good point about how camber changes with suspension position. Also the effective track width changes, such as with my 4Runner which has upper and lower control arms, a Double wishbone suspension. If the motor remains in a fixed position, the wheel will move onboard and outboard relative to the motor depending on suspension location.
I don’t quite get how these two effects are addressed with this new design. Or are the suggesting a different suspension technology that they didn’t discuss?
As for steering, I wonder if the design rotates the motor along with the wheel. In that case no CV is needed but I would guess there are some downsides to such a design.
I agree the video seems kind of… premature. The mechanism is cool but I don’t get the sense that its applications haven’t exactly been nailed down yet.
Individual motors on each wheel will still slip, just with half the power. So sure, it’s an improvement by an unrelated mechanism, but not having the wheels connected with a limited slip means it’ll still need a traction control system. And even still, the “half” power is a relative term because every car has a different output. That goes for not connecting left to right as much as it goes for front to back. So, not different than a traditional open diff or 2wd. There have been advances in brake-based traction control so they don’t just cut power and apply single brakes like the 00s, they can properly modulate pressure to get equal propulsion.
That’s a good point you’ve mentioned as well - the wheel will change distance to the motor as it goes through it’s motions. The only way to avoid that is to place the motor at the effective pivot point of the suspension which is, in a properly design suspension, inside the other wheel to mimic the level dynamics of a solid axle. That of course defeats the short halfshaft design direction. So something has to allow variation in distance. In the non-steer wheels, maybe this could be as simple as a telescoping spline drive. However, the video shows a small black joint at the same time stamps above on the rear and still has those normal-looking cv boots on the fronts.
Or maybe they’re ditching good handling and going with perfectly vertical suspension travel. Give it hard eco tires and it’ll slide before the suspension shows it’s flaws.
The steering wheels’ hubs rotate in two directions. The steering action rotates through a vertical axis while the typical suspension rotates in a front-to-back axis pinned approximately through the other side of the car. So unless they abandoned common suspension design to let tires lean in turns more than a reasonable amount, there needs to be an allowance for angular deflection. A pinion gear arrangement sounds like it would take up a lot of the space they’re trying to save but still not solve the multi-axis problem found at all 4 wheels. I’m trying to not take their video so literally but it’s not like it’s a dealership rep spouting incomplete info here
Unrelated comment, but holy shit I am a huge fan of the M8. So wild to see you on Lemmy, and this comment section is exactly what I’m here for.
But you need a CV or Universal on that drive shaft to accommodate suspension travel (or steering if needed on that wheel).
- You are sort of correct about this, but it’s irrelevant since everyone moved onto limited slips decades ago.
As to the rest- you’re wrong. Sorry.
But the real reason this tech won’t be very important is because it’s a lot more complicated and expensive than a cheap ass cv joint and is minimally more efficient. I can buy both sides of my vehicle for like $80 and don’t have to worry about em again for ages. I think this new hyundai stuff could be reliable, but it’s going to be a lot more expensive.
Also, they look like they’d be noisy.
you’re wrong. Sorry.
No u. Bam, same level argument right there. Are you going to explain why or just throw out contrarian comments?
Cost will not be a limiting factor. Just about every feature on a 2023 car already costs more than a 1993 car’s version. Did adding a wheelspeed sensor, electronic 4-channel hydraulic brake actuator, and dedicated ecm programming cost too much to implement ABS? Did the complication of 40 sensors (100+ now) and a voodoo box of electronics cost too much to go efi instead of carbs? Did the price of disc brakes stop most cars from ditching rear drums? Did the cost of engineering and testing prevent manufacturers from implementing the following nearly-negligible aero improvements to eek out another 0.1% of fuel efficiency;
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aero strakes into mirror shells (prius, escape)
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relaminating roof spoilers into every hatchback/suv and even into every pickup bed
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Vortex generators on the top surface of tail lights (sonata, chr)
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Active grille shutters (fusion)
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Full underbody trays
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Chin spoilers (splitters) on just about every car to keep air out from underneath
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Hood beak splitters to keep grille air off the canopy (Volvo, accord)
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Short antennas/glass-embedded antennas to reduce antenna drag
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Front fender outlet vents to create laminar flow over the wheels (f150 2015+)
No, it didn’t.
And I’d be interested to hear why you think helical-cut gears will be “noisy”. I’m guessing you don’t know why reverse whines in certain cars but not the forward gears
Edit: also, seriously, go do some shopping. LSDs are on the decline. On top of never being common in the first place, manufacturers at removing to brake-based simulated LSD rather than discrete components. There are incredibly few Fwd cars that ever had LSDs and fwd obviously makes up the majority of North American sales. Even Miatas and Mustangs only get LSD with optional packages.
Yeah the amount of BS or confidently incorrect in tech articles about automotive engineering is crazy.
And while gear-sets are really efficient, adding 8 to each of the 4 wheels 32 total, in leu of 2-4 at each end of the car, plus 4 CVs (assuming it’s AWD) has to be close in efficiency. And as a DIY+ car restorer in New England. I wanna see how they seal this thing. And with steering wheels it’s either gonna have to swing the motor around or put the CV back in anyway.
NVH (noise vibration harshness) is also going to be a huge factor. That and cost and weight is why we don’t have gear driven camshafts except on a select few exotic motorcycle engines and F1 engines.
Helical gears are the cost effective way to reduce gear noise, but they impart axial loads which would be difficult to overcome in this hinged joint. Herringbone fears eliminate the axial load, but are much harder to make, unless you go with powdered metal sintering. Which I barely trust in a cordless drill, let alone a Kia.
Edit: And no accounting for wheel castor, or camber changes along the suspension travel (way more basic and important for handling than torque vectoring). This video is pure marketing wank.
Irrelevant since everyone moved onto limited slips decades ago.
Lol, what?
My RSX was made two decades ago in '03, so the newest that would be multiple decades old. It’s also a Type-S, the sporty model. It’s got an open diff.
My '93 Subaru Loyale, which is 3 decades old, has two open diffs, with a locking center diff. No limited slip.
My '04 (almost decades old) Crown Vic PI doesn’t have an limited slip. It was an option on Interceptor that the city didn’t opt for.
My '07 (not decades old) Volvo XC70 has no limited slip diffs. It uses the traction control to try to imitate them, but no actual limited slip differentials.
My partner’s '07 (still not decades old) Kia Spectra5 has an open diff.
The only car in my fleet that has a limited slip is my '02 Subaru Legacy Outback, and it was an option that the person who bought it new opted for, and it’s just the rear that’s limited slip, the front is still an open diff. Apparently the limited slip isn’t even that good either, you can still get stuck with two wheels spinning. I haven’t tested that yet, I just got the car.
If you go out and buy most cars today they’ll come with open differentials. The traction control system will likely try to compensate for this, but they do not have limited slip differentials.
Yea, companies love to tout their “electronic differential” that’s nothing more than an open diff and traction control via the brakes (Toyota Tundra comes to mind, as recent as 2017).
Now thar Hyundai has patented it, it will never become popular enough to impact the market and be standardized in more vehicles or change anything, similar to the Wankel engine.
similar to the Wankel engine
Was the Wankel engine really a step forward though? I’m a gearhead who does all his own car maintenance, up to and including engine swaps in the past and retro-modding bigger turbos and aftermarket fuel injection systems into my cars (Datsuns in the latter case). That being said, I only know the very basics about rotary engines. I’ve always admired the Mazda RX’s from afar.
Mazda, who by no means makes a bad gasoline engine, could never get a rotary motor to last well or to have anywhere near decent fuel economy. Also, the rotary design was tried for a while in at least refrigeration compressor applications, where it blew up there a lot more than the other types of compressors as well.
Yea. They have worse efficiency. To get better efficiency from them you would need to run them hotter (afaik), and if you do that they would last even shorter.
It’s great if you want a smaller but still strong engine, but it’s not efficient and those seals are a big problem.
The problem with the rotaries is a result of the technology of the time and funding.
They are inefficient because they lose compressed fuel and air as the seals pass over the holes for the spark plugs, which can be largely solved with laser ignition. They are less reliable because of the design of the apex seals, which can be solved by using a roller instead of a blade. Both of those major issues with the rotary could not be solved with the technology of the 60s-00s and the tiny budget available. There are other issues that hold back the design, but those come down to metallurgy and manufacturing processes. Mazda did a great job trying to make the rotary work and it almost killed them.
The other issue that gives then an unreliable reputation is because you can’t treat them like a piston engine and people treat them like a piston engine. Hard to fault the knife for breaking when it was used as a pry bar.
The argument is, though I’m not qualified to assess it, that Wankel engines are simpler, smaller, more power dense and, if allowed time to develop, would be an improvement on the traditional ICE. It’s very difficult to assess where we would have ended up and a little by the by, given we need to move away from burning fossil fuel.
That said, do check out LiquidPiston’s evolution of the Wankel engine. It does sort of look like they’ve solved a number of issues a traditional Wankel engine has.
if allowed time to develop
The basic problem with Wankels is that the geometry of the combustion chamber (such as it is) is constantly changing, which inevitably results in incomplete combustion compared to traditional ICEs. This leads to lowered fuel efficiency and greater emissions; the emissions problem is solved with an additional combustion chamber for the exhaust gases, but this consumes more fuel and lowers efficiency even more. It’s just a fundamental problem with the technology that no amount of development could ever fix.
Some people argue that intellectual property law is not free market capitalism, and is instead a regulation that benefits big business. I’m one of those people
While I’d agree in essence, in practice I don’t. They’re an offshoot of capitalism. The goal of capitalism is profit, and if you can create barriers to competition, that protects your profit. IP law is something created out of capitalism as a barrier. If it isn’t the government doing it, it’d be goons hired by those in power. They exist because of capitalism, not from something external to it. If the system were focused on doing good or creating utility, IP law wouldn’t be required.
Free market and capitalism are mutually exclusive as in the theoretical model that is the free market, with perfectly rational actors and information, a capitalist class cannot exist, they’d quickly get competed down to size.
Unregulated markets and capitalism, now that’s a lovechild, as without regulation real-world markets quickly turn into monopolistic shark-tanks instead of free markets, actors not being rational, information not being perfect and all. The role of regulation, indeed the state, is to correct for that factor and make the real-world market approximate the free market.
(This view of the world brought to you by ordoliberalism, the only sane liberal economic theory there ever was or probably will be – because they actually managed to side with the free market, and not capitalism, as the rest of them).
Did none of you watch the video? The article is crap, but the video explains it well.
Go back and watch the video, ya old codgers!
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