The usual concern about such things is additional unsprung weight. I also wonder about cost of repair when relatively minor impacts with wheels occur. Interesting.
They seem to have ditched the hydraulic friction brakes to make space within the wheel, so you'd drop a bunch of weight there... but then, whats the situation with braking?
@@noxious89123 I think they didn't include the brakes for simplification of the visuals. I would imagine the wheels would be inboard like they do with the bollinger EVs (anybody remember them?)
@@noxious89123I guess this unit needs to be oil filled, wich create a mass that has a damper on the start of the movement and a momentum when the movement must stop. That will cause some problem. But I guess this is not a racing car system, good enough for everyday use?
Yeah....but U really gonna go off road with battery pack underneath. Deep pot holes can create havocs but like buses, trailer tractors, and wheelchairs (rear wheel drive).. this is perfect.
@@timeconomu7395Gas tanks are usually higher up on the car than the battery packs on these modular chassis. If you puncture a gas tank you just get a leak, if you puncture a lithium battery you get a gnarly fire or an explosion. Not saying that these concerns couldnt be accounted for, but they are concerns none the less.
I couldn’t help but notice they still had to use one cv joint on each front wheel for turning. So on a 4wd car with 2 wheel steering they are reducing the number of cv joints from 8 to 2, but not eliminating them completely like the video seemed to be saying. Also on a fwd car it would only reduce the number of cv joints from 4 to 2.
I have no idea what type of joint Hyundai is proposing,@@TheThomSirveaux, but any joint which doesn't change speed with rotational position is a "true" constant-velocity joint. To handle a steered axle, almost the same angle as conventional applications would be required, so it would presumably be a conventional CV joint type.
Could always mount the motor on a “hinge” and have it turn/camber in relation to the UWD hub assembly and shaft as well. Eventually I’m thinking each wheel will get something akin to a “bogie” mount like rail cars. Especially since drive by wire is already a thing and steer by wire will be more popular too. In this manner, steering would just mean varying the speed of each wheel to allow them to pivot in their bogies similar to how a tank or a hoverboard turns.
I really love this idea. Cars are basically the shell and internals, wheels are all about the power and ride. It's so modular that all manufacturers could get onboard
But... You still need a CV joint between the uniwheel and the drive motor to account for steering. The uniwheel only allows an up and down movement in a single plane. Otherwise the design is top notch. Good job Hyundai!!
Looks like in the video they envision the small motor being able to turn with the wheel? You'd think having to have space for the motor to turn with the wheel would take up a lot of space too. Although I guess this would be ideal for a rear wheel drive car.
@@OrestisTripsthanks for the link. You have to zoom in on the small picture but it’s clear that the motors turn with the wheels. They should go for axial flux pancake shaped motors. That’d keep the whole package tighter
Possibly a brilliant innovation. However, I suspect durability could be a potential tradeoff. For example, taking a pot hole or speed bump at some speed looks like it would result in the system violently reaching its limits of travel and becoming easy to damage in many ways. Also, I wonder if going through some water or mud could get debris into the system. The video seems to breeze over the comparison part and just says the system performed "satisfactorily," which implies just okay enough but likely a step back. Guess we'll have to wait and see.
Y'all are overthinking this, this something you put in a car. It basically data to improve the product or to be adopted to another industry. Example 4 wheel steering. Bad for gas pickup trucks but good for ev trucks
This is Uni-Dumb. Go to time mark 4:22 where you'll see a close up of the electric motor plus uni-wheel and you will see that the power train assembly still has the constant velocity (CV) joint that they just spent time trashing! The CV joint is needed in their design to handle the angular wheel movement incurred when you turn the car left or right (angular movement of wheels is conveniently left out of this video). Notice how the parts of this video showing how the uni-wheel works only show it handling deflection in 2 axis - up/down & forward/back but not angular deflection. Keeping those extra small uni-wheel gears sealed and lubed and working for 200,000 miles will be a challenge. Also, I'll bet it was a challenge counteracting the outermost planetary gear's tooth separating force that wants to cause the outer planetary gear to move inwards and disengage. What counteracting force keeps that outer planetary pushed outward, the torque somehow? I Would love to see that force diagram. Solution - Guys, you gotta include the electric motor in your uni-wheel hub to make it a complete self-contained powered drive module that moves with the wheel. Then you can get rid of that overly complicated gazillion spur gear uni-wheel mechanism and just use a traditional planetary (1 central sun, 3 plant gears & 1 ring gear). You can also get rid of the CV joint entirely. This true uni-wheel would be powered electrically by a beefy but flexible and shielded-from-the-elements power cable that will flex as the wheel both turns left/right and also when it moves up/down. You will get even more interior room with this suggested design, it will be more mechanically robust, and it will cost less money. Back to the CAD terminal Hyundai!
That's just a boot to cover the connection. The entire motor and gear assembly moves together with the pivot being at the motor. Check out 5:17. When the car turns the motor turns as well. How would the outer planetary gear move inward? They are fixed in place. See 3:00. Having all the weight in the wheel is a problem that causes major handling issues. This looks to be a solution to that.
@@kamX-rz4uy Thanks. At time 5:17, I'll agree that the motor housings look like they are tilted a small amount, but the turn is too shallow for me to tell what I am looking at. One thing is for sure, if the motor was affixed to the wheel hub, like I am suggesting that they do in a redesign, then they would not need to make such a complex mechanism (covered in the majority of this video) to compensate for the wheel moving up/down independently from the motor which is clearly locked from moving up/down (hence the need for their goofy planetary) which is why it seems logical that the motor is also locked from angular motion too and that it is basically just bolted to the car's frame. The boot that you say "covers the connection", is egg-shaped and looks like a regular CV joint cover. Also, I don't see any bracket holding the motor to the wheel hub assembly. The motor housing has to bolt to something that does not rotate to allow it to apply torque to the wheel. It can't be just hanging out there. I'm still convinced that they are still using a CV joint and therefore have designed something that is the worst of both worlds.
In wheel or wheel hib motors have a long history, go back to the Michelin Active Wheel and a Siemens eCorner; More recently Kightyear and Lordstown used in-wheel motors before both filed for bankruptcy, and REE Is going to make small trucks using its motors now that no OEM seems interested in buying the components. Inboard motors and short drive shafts work fine. These alternatives have to be dramatically better, and it's still an uphill slog to get any car maker to consider them.
In-hub motors are a no go for full size vehicles meant to drive at highway speeds. No matter how you engineer them , two main factors will always be a problem - available space and weight. Wheel hubs should be as light as possible to reduce unsprung weight, too much of which causes very undesirable vehicle dynamics. Because of the limited space and low weight goals, engineers will have to settle for smaller motors and have more limited gear ratio options. You’ll also have to have all the motor cables run from the hub to the chassis which exposes them to harsher environments than if they were exclusively within the chassis.
I just wanna know, how to cool down and lubricate the gears ? How to seal the giant open gap and keep the shaft movable under extreme conditions such as water, dirt and rocks.
They are either going to have to have the motor swivel with the wheel (which would take up too much room), or use a CV joint, though one that is possible smaller, lighter, and needs less up and down range. (It's at higher angles on the CV where efficiency is lost).
@@mychaljwit seems like they do both in this concept, there’s a visible (CV?) joint and the motor swivels as well. It seems like a lot of effort to reduce the number of joints from 2 to 1 per wheel and the maximum joint angle without completely eliminating either one. It probably will still be worth the space savings and modularity, but IMO the success of it hinges on how compact they can make the mechanism that turns the whole motor/shaft assembly while maintaining strength and accessibility for repairs. I’m all for a redesign of traditional approaches so best of luck to the team!
Well, since there are independent motors, it would be possible to steer by having the outer wheels spin faster than the inner ones. Although, I guess it wouldn't be the pinnacle of efficiency (or safety).
@@mychaljwWell, yes. But also like the rear wheels of pretty much every car (that doesnt have a blocked diff). But I agree, not the best solution at all.
Humvee’s use a gearbox at the wheel, very interesting engineering feat. My biggest question is how you seal that input shaft through its range of motion? followed by how is it lubricated? I would assume a serviceable gear oil fill of some form? I don’t know why I’m asking as if I’m going to get a response 😂
HMMWVs (Humvees, and civilian Hummer H1's) have geared hubs for portal axles. There are other vehicles with portal axles (mostly older than the HMMWV) and lots of heavy trucks with geared hubs just for more reduction. It's not much of a feat, but it is interesting to see. I agree that sealing the sliding entry panel would be a major issue if this were ever actually considered for production.
This isn't a portal axle in the sense of a solid axle or independent like hummer. Further they do not mention lubricant or dust boot concept. They have not thought this far or maybe it's still being patented. Its huyndai they are not fools. I can see this working at low speeds where heat doesn't play a role and it will probably be OK with flat surface and things like steps.
@@brianb-p6586 el sellado y lubricado del sistema no sería demasiado inconveniente.. con una buena grasa para engranajes, y un buen mantenimiento,, puede durar años... La junta tipo fuelle , al estilonque usan en los palieres actuales podría valer... Lo malo la corrección de las variaciones en el sentido axial...
ruclips.net/video/3-Th5yKxVBg/видео.htmlsi=tgJ_YapVEqQG8SM- A few days ago, there was a technology presentation in Korea. They said that lubrication and cooling are currently being tested. The biggest key is steering. So, first of all, it said that they plan to apply it to the rear wheels next year.
I see it as a very interesting concept, but I think it creates more problems than it solves. In my opinion there are lots to solve: sealing between the axle and the hub, between the outer drum and the hub. Also having the motor turn with the wheel seems simple but it's not: you need to align the motor with the steering angle of the wheel and at the same time to separate them in the vertical direction, so this needs an additional mechanism with probably lots of parts. The steering/pivot axis of the wheel/hub assembly changes as the suspension is compressed as does the camber angle of the wheel. Also steering response would be worse given that the motors need to pivot/move when you turn the steering wheel, it will behave as a sort of flywheel. A better solution would be with the cv joints but that still has the sealing issues. Regarding power efficiency: the torque is transmitted through 5 gear pairs, in comparison in a Tesla Model S drivetrain you have 2 gear pairs, so I think efficiency will be much lower because of friction losses in the gears.
Efficiency would be greatly improved. Torque load on any motor is significantly reduced, this translates into a much greater amount of usable drive torque ie: torque/power that the actual tire can apply in the direction of movement to the ground. (A smaller motor turning the uni wheel can achieve the same speed as a much larger one turning a standard wheel)
@@Howya_fishbin For Tesla model S the gear ratio is 9.734:1 or 9.325:1 according to wikipedia. Uniwheel has about 6 maybe 6.5 measured on the screen, even though I know this is not precise, the gear ratio is far from 9. Also don't be fooled by the many pinion gears, the gear ratio is defined by the sun gear and ring gear.
@@s_attila It is important to consider that with the internal hub the gear ratio can be increased virtually "infinitely" 😉. Further, the gear spins so that torque is applied to the inside of the wheel much like a track drive. With the internal gear and the "track like" setup torque load can be reduced to practically zero. Something to consider....what if a hydraulic motor were to turn the planetary gear set? This would again result in more usable power while lowering any input of energy needed. Also a hydraulic motor would eliminate the necessity for any cv joint as there is no mechanical connection...only a hydraulic hose. 😄 Haha, another note....a hydraulic motor turning the uni wheel can achieve much greater power with significantly less weight than say an electric hub motor.
Give it some time. He's currently breaking down all the equations, pros and cons. And when he's finished his hair will be grayer than Einstein himself lol.
The Unimog introduced in 1948 and still in production) and the better-known (in North America) HMMWVs (Humvees, and civilian Hummer H1's) have geared hubs for portal axles. There are other vehicles with portal axles, and lots of heavy trucks with geared hubs just for more reduction. None of these geared hubs allow the input shaft to remain stationary while the suspension moves, which is the novel feature of this Hyundai design.
“how are they gona lubricate these gears” - No way. The first three years, while the wheel is under warranty, it will not have time to rust and pick up much dirt, and then it is the owner’s problem, your problem.
Wouldn't a hub motor still be the better overall solution? Especially for "normal" cars that don't need loads of power and could use smaller motors. Less moving parts, simpler and maybe less overall weight, but with the penalty of more unsprung mass - which could be offset by not using only-for-looks ginormous wheels (who needs 21s on a family SUV?!?)
Gearing is the most limiting factor right now. It's easier and safer to make a high speed EV motor to compensate for the gearing than to make a motor that draws enough amps to start from a stand still with 1:1 gearing at any amount of briskness.
@@Mark_Proton you are right for direct drive motors, but you could use a planetary gearbox. Adds weight, but can be very compact and the motor could be smaller. But I‘m only an armchair expert tbh., not an automotive engineer.
they've nearly acomplished exactly what you're suggesting. the difference between the hub motor as youve described and the uniwheel is the unsprung weight of the motor being shifted into the hub vs on the frame. There is an efficiency loss caused by shifting weight to heavier wheels as well as a bumpier ride.@@meltdown78
While regenerative braking can be expected, the vehicle will need a braking system somewhere in the drivetrain. With gears in the wheel hub, the open question, where are the brakes?
@@michaelstafford648 Traction braking. Adding a parking brake is trivial. Believe me, you are not outthinking Hyundai's entire R&D department or thinking something they haven't thought of.
How does the input gear/shaft stay centred and not fouling on the housing when stationary? I get the it will naturally centre once the wheel starts spinning but the moment it stops the weight of the car will guillotine the input shaft.
Ok, so this is awesome for the up and down motions of the wheels. Is a CV joint still used for turning? I have more questions but so far this looks REALLY promising :)
If you look at around 5:17 you can see a single CV joint on the front axle. You can still place the motor much closer to the wheel because you don't need long driveshafts, just a single, small CV joint. And as far as I understood this also replaces the transmission - putting it into the wheel and saving space.
You can see a joint (@4:20) is still used in the video attached to individual motors with a short shaft. They also claim they have passed the first round of testing @4:47. One would think turning was involved.
@@techpappee "OnE wOuLd ThInK" No shit Sherlock. I saw the CV joint. However, the way they are going on about not using them, they make it seem as though they wouldn't. As for testing, it doesn't mean they did the testing in road vs simulated environments in a lab.
5:12 shows that the motors pivot with the steering assembly, staying perpendicular to the wheels. More complexity in the steering assembly, then, but they apparently judge this to still be worth the improved system-level packaging requirements?
5:12 shows that the motors pivot with the steering assembly, staying perpendicular to the wheels. More complexity in the steering assembly, then, but they apparently judge this to still be worth the improved system-level packaging requirements?
It does look like smaller parts are involved, so manufacturing costs and durabiluty will be my concerns… But fantastic ideas, really hope more testing will be done
When a traditional system car goes over potholes, the motor and all of its moving parts do not get a lot of shock, it is absorbed by the wheels, and other dampening parts (I forgot what they are called). This new construction, it seems like it will be getting a lot of that shock and possibly break down too. And I don't doubt this construction doing well for 1-5 years. Can it survive 7-12? I think it is for a good reason that such complex part as the engine or car motors are getting the same protection from shock that the driver gets. It is intricate and susceptible to costly repair if it wasn't. That is my concern despite me being very excited to see how it works.
Now there is a hope in the automobile industry. I was always wondering about why the designers does not give a touch for a better automobile drive experience.. it was always about exterior design which they care and some minor interior details. Even EVs were after that.. However the drive itself was not considered as an improve area element. Whatever... I am veeerrryy happy to see that it is now the time. Thank you Hyundai❤❤❤
A cool concept but seems much more complicated than ordinary shaft drive. Also, it has more moving parts. Thus there are more things to break down and it's more expensive to build. Also, it increases the wheel's unsprung mass which is also not a good thing.
This is a modification of the in-wheel motor design. So drastically reducing the unsprung weight and eliminating the motor's exposure to shocks from potholes. Although, yeah, more unsprung weight than a traditional wheel, but I don't think unreasonably more.
Remember in this case they’re moving the reduction gear and final drive to the wheel hub so the parts count is virtually identical vs the traditional CV joint setup. It’s modular and easier to service too.
@@starrwulfe are you sure it won't end up as unserviceable self-contained wheel assemblies where you have to buy a new one every time something goes wrong?
interesting idea. Personally, I expect a lot of unpleasant noise emissions due to the gearing and the very high speed of some components. These speeds certainly also limit the overall usable speed, 120km/h in the video. Another issue will be the sealing of the mechanism and the total number of parts of the mechanism >>> potential failures. The total weight of this device will probably not be negligible either (unsprung weight). And lest I forget, does anyone mind that the vehicle has stopped turning? Or was I looking at it wrong?
My guess is that it will either be inboard or they'll minimize it as much as possible and expect regen to be able to pick up the slack, which it can't do in all conditions.
basically, in between traditional driveshaft and hub motor. It all goes down to difference in unsprung mass and costs/reliability. Hub motors almost certainly win on the latter. Not sure Uni Wheel is winning on the unsprung aspect either. Not going anywhere, anytime soon. And, I think I can do better! :-P
Would this be able to tow anything? Seems like that would be a lot to ask of those little gear cogs to pull a few thousand pounds of boat or camper or whatever in future vehicles
Protean goes one step further and has the motor as part of the wheel, which is an even greater step. The argument against it would be the larger unsprung weight of the wheel, but one may argue that city travel means hopefully fewer potholes to contend with. Those solar EV challengers with PV roofs all had motors in wheels.
Individual control of torque to each wheel is claimed as an advantage as if it has anything to do with this design, but it does not. One-motor-per-wheel works with any motor location and shaft design.
"Simple and elegant" - Simple? Where did you see “simple” there? From a really simple and cheap wheel they made a complex monster with 11(!!!) gears. Let them voice the price of such "simplicity".
Would it be possible to also get rid of the conventional brakes and incorporate all braking into the drivetrain? Brake rotors that rust and brake calipers that seize up from corrosion is a major issue where roads are salted during winter...
Until now when you hit a pothole you might have to replace your wheel or tire from now on if you hit a pothole you have to replace your whole drivetrain the future of car driving
So, why not just use the already existing hub motors that i see in things like the Onewheel? Can that not be scaled up? How is this more efficient than that?
Hub motors on full size vehicles, or ones meant to drive at significant speeds, would suffer due to the large amount of unsprung weight, and having the motor and the gear reduction on the hubs limits either the available ratios or the motor size. Splitting them offers better handling and potentially more power from larger range of motor choice.
Did I get it wrong ? its inside the wheel , not a part of it , therefore its not rotating with the wheel making the actual wheel heavier / harder to move . I think thats what is happening . I could also be wrong but it appears to have less mass in general then with regular drive shafts etc so gross weight is reduced . I could be wrong again but although not increasing rotational mass being directly inside the wheel whatever mass it has is directly OVER the wheel / s which I would assume on some level helps plant the wheel via its weight and the mass is evenly distributed over 4 wheels for instance further increasing AWD ability to transfer power compared to RWD or FWD and purportely you dont have fluctuations in torque delivery with the angle changing etc so less drivetrain loss and all of those would seem to mean better acceleration from the power availible / no waste , as is the case with transmissions going to differentials etc that all "eat " power and why HP is rated at an engine ( potential power) but also measured at the wheels to know how much actually makes it to the wheels . Having each one independent also means super duper torque vectoring which means even less likelyhood of spimming the tire which turns HP into heat and smoke without full use of power to move car as well as reducing tire life . The movement they show would also suggest better contact patch when surface changes putting less pressure on tires in different situations which would mean longer tire life even if driven hard instead of eating up outside of tire etc to where you have more tread on part of the tire but once you remove more tread in a specific area you reduce traction / performance and would need new tires despite some section of tire being in good shape with use left . Everybody who drives fast or hard , had alignment issues or set up a car a certain way has had to get new tires despite a good section of the tire looking and being good and that is a drag , you might try an wait to get more miles but you lose a bunch . Regular ICE AWD cars even have issue if 1 tire has significant wear compared to others changing diameter which throws off the gearing / differentials meaning needing to replace tires so all are even or shaving a new tire to be same diameter ( throwing away brand new tire reducing miles it will be useable) . With NONE of that and truly independent wheels that is no longer a concern or less concern as each wheel optimizes for its tire even if slightly different then the others . If those gears are strong or strong enough for whatever power will be put through them it looks to be a win , But real world is real .
Holly unsprung mass... And could you imagine the meshing noise? What about the brake rotors/disks? Are they going to be inboard? Looks like a perfect solution for a problem that never existed in the first place...
There's no free lunch. Such a system will have much higher unsprung weight, and would behave worse over bumps. Also, it may have a higher rotational mass, making breaking and acceleration slower, to some degree.
Sorry folks, this is not viable. The pinion drive train would need dozens of bearings, each that would spin so fast their packed grease would fly out. Since you can't use grease, then you need hydraulic fluid. Anything other than rotational motion is basically impossible to seal, so the suspension gearbox itself is not viable. Also, no animations were shown on how the wheels turn left or right. The gearbox does not appear to have any freedom of movement in the direction of a turn. Also, since wheels are no longer coupled and driven from a common power source, if one motor or drive train should fail, the car will pull to either side which is a safety hazard. The flip side to this is also with breaking. This could be overcome by smarter software, but mechanically linked drivetrains don't require software to work right and reliably. The most optimal solution is to design the motor field coils themselves to be embedded directly in the wheel hubs. Beneath large ships they are already doing this with their articulating propellers driven by very large coils in the surrounding enclosure. The propellers essentially spin on bearings in the the center. The torque comes from the coils directly on the outer diameter of the propellers. If you are going to put a motor on each wheel, might as well put it right in the hub, then you completely eliminate all gearing, and drivetrain. Think of each wheel like a beefed up brushless fan motor. Motors can be made to do this for torque or speed, but probably not both unless you could find a way to reconfigure the battery packs from series combinations of cells into parallel combinations. Parallel combinations would be used for large torque at startup. Series could be used for fast speeds on the freeway. You need the extra voltage to counteract the back EMF from the motors spinning increasingly faster. Regarding the problem with unsprung weight added to each wheel, that's mainly due to the jarring effects of pot holes and other serious vibrations. Mount the motor coil in each hub, but make it be a planar orientation with built in shock isolation. In other words, put all the complexity of that gearing mechanism into a relatively complex motor suspension system built into the hub. Free to move up and down, but not spin. I don't know why nobody has tried or even touted this yet. Sometimes I wonder why engineers over-complicate stuff...
The percentage of increase in efficiency remains unrevealed, indicating that it may be a small figure. However, the space saving property of this technology is indeed very innovative and I look forward to seeing it integrated in new vehicles. Hopefully not just in South Korean vehicles. Considering the global automobile theft statistics, waiting for Kia/Hyundai to perform an overhaul on their anti-theft systems before purchasing one of their vehicles, may be recommended.
I am hopeful for this technology to be developed for mass applications if it can be proven (efficient, reliable, durable, ...) But don't know if it will be better than wheel/hub motors. They too will continue to get better.
@hyundai motor group, why not move the electric motor to inwheel? Seems only the drive is moved. What challenges you faced moving the electric motor itself inwheel? If motor is inwheel, the whole thing could be evolved to drive-by-wire.
They should just invert the implementation. uni wheel on the inside. less complex moving parts and unsprang weight on the wheel hub. with the current design with all small worm gears and pivots, linkage transferring huge torque. Hyundais will have to increase roadside assistance.
The usual concern about such things is additional unsprung weight. I also wonder about cost of repair when relatively minor impacts with wheels occur. Interesting.
It looks pretty modular. It might not be any worse than a traditional CV joint replacement.
They seem to have ditched the hydraulic friction brakes to make space within the wheel, so you'd drop a bunch of weight there... but then, whats the situation with braking?
@@noxious89123 I think they didn't include the brakes for simplification of the visuals. I would imagine the wheels would be inboard like they do with the bollinger EVs (anybody remember them?)
@@noxious89123I guess this unit needs to be oil filled, wich create a mass that has a damper on the start of the movement and a momentum when the movement must stop. That will cause some problem. But I guess this is not a racing car system, good enough for everyday use?
@@noxious89123Brakes can be mounted on the motor/driveshaft? Just like old Alfa Romeo and Citroen did to reduce unsprung weight.
Interesting. We’ll have to see how it survives in real-world conditions, including going over potholes and going off-road.
Yeah....but U really gonna go off road with battery pack underneath. Deep pot holes can create havocs but like buses, trailer tractors, and wheelchairs (rear wheel drive).. this is perfect.
@@Timbucktoothed Why not?
I think so. THink of all the holes in gas tanks right now. We gotta solve that problem.
@@timeconomu7395Gas tanks are usually higher up on the car than the battery packs on these modular chassis. If you puncture a gas tank you just get a leak, if you puncture a lithium battery you get a gnarly fire or an explosion. Not saying that these concerns couldnt be accounted for, but they are concerns none the less.
@@captaincannabis3321 Blade battery is passes Nail penetrations test
I couldn’t help but notice they still had to use one cv joint on each front wheel for turning. So on a 4wd car with 2 wheel steering they are reducing the number of cv joints from 8 to 2, but not eliminating them completely like the video seemed to be saying. Also on a fwd car it would only reduce the number of cv joints from 4 to 2.
Even the non-steered wheels need some angular compliance because toe and camber angles change with suspension movement.
@@brianb-p6586I'm also guessing that it's not a "true CV" joint, in that its range is limited in order to increase power transmission efficiency.
I have no idea what type of joint Hyundai is proposing,@@TheThomSirveaux, but any joint which doesn't change speed with rotational position is a "true" constant-velocity joint. To handle a steered axle, almost the same angle as conventional applications would be required, so it would presumably be a conventional CV joint type.
Could always mount the motor on a “hinge” and have it turn/camber in relation to the UWD hub assembly and shaft as well. Eventually I’m thinking each wheel will get something akin to a “bogie” mount like rail cars. Especially since drive by wire is already a thing and steer by wire will be more popular too.
In this manner, steering would just mean varying the speed of each wheel to allow them to pivot in their bogies similar to how a tank or a hoverboard turns.
@@starrwulfecomputers will handle that
I really love this idea. Cars are basically the shell and internals, wheels are all about the power and ride. It's so modular that all manufacturers could get onboard
Only when you let go of old habits can you make room for real new possibilities! Keep innovating!
But... You still need a CV joint between the uniwheel and the drive motor to account for steering. The uniwheel only allows an up and down movement in a single plane. Otherwise the design is top notch. Good job Hyundai!!
Looks like in the video they envision the small motor being able to turn with the wheel? You'd think having to have space for the motor to turn with the wheel would take up a lot of space too. Although I guess this would be ideal for a rear wheel drive car.
A lot of 2WD EVs are RWD already, so I expect we'll see more of them in the future with something like this, @@travisflynn2160?
5:12
Not just up and down: ruclips.net/video/Nd6C0y8xc20/видео.htmlsi=IqbhCBK__GWs-W0Z&t=172
@@OrestisTripsthanks for the link. You have to zoom in on the small picture but it’s clear that the motors turn with the wheels.
They should go for axial flux pancake shaped motors. That’d keep the whole package tighter
Possibly a brilliant innovation. However, I suspect durability could be a potential tradeoff. For example, taking a pot hole or speed bump at some speed looks like it would result in the system violently reaching its limits of travel and becoming easy to damage in many ways. Also, I wonder if going through some water or mud could get debris into the system. The video seems to breeze over the comparison part and just says the system performed "satisfactorily," which implies just okay enough but likely a step back. Guess we'll have to wait and see.
室内で使うロボットや都市部での車椅子には向くと思うが、実際の公道や悪路には不向きだと思う。
四輪の制御も複雑になるしコストや耐久性やメンテナンスも考えると現段階では まだまだ研究室レベル、実用ではデメリットが勝ると思う。
Y'all are overthinking this, this something you put in a car. It basically data to improve the product or to be adopted to another industry. Example 4 wheel steering. Bad for gas pickup trucks but good for ev trucks
This is Uni-Dumb. Go to time mark 4:22 where you'll see a close up of the electric motor plus uni-wheel and you will see that the power train assembly still has the constant velocity (CV) joint that they just spent time trashing! The CV joint is needed in their design to handle the angular wheel movement incurred when you turn the car left or right (angular movement of wheels is conveniently left out of this video).
Notice how the parts of this video showing how the uni-wheel works only show it handling deflection in 2 axis - up/down & forward/back but not angular deflection.
Keeping those extra small uni-wheel gears sealed and lubed and working for 200,000 miles will be a challenge. Also, I'll bet it was a challenge counteracting the outermost planetary gear's tooth separating force that wants to cause the outer planetary gear to move inwards and disengage. What counteracting force keeps that outer planetary pushed outward, the torque somehow? I Would love to see that force diagram.
Solution - Guys, you gotta include the electric motor in your uni-wheel hub to make it a complete self-contained powered drive module that moves with the wheel. Then you can get rid of that overly complicated gazillion spur gear uni-wheel mechanism and just use a traditional planetary (1 central sun, 3 plant gears & 1 ring gear). You can also get rid of the CV joint entirely. This true uni-wheel would be powered electrically by a beefy but flexible and shielded-from-the-elements power cable that will flex as the wheel both turns left/right and also when it moves up/down. You will get even more interior room with this suggested design, it will be more mechanically robust, and it will cost less money.
Back to the CAD terminal Hyundai!
That's just a boot to cover the connection. The entire motor and gear assembly moves together with the pivot being at the motor. Check out 5:17. When the car turns the motor turns as well.
How would the outer planetary gear move inward? They are fixed in place. See 3:00.
Having all the weight in the wheel is a problem that causes major handling issues. This looks to be a solution to that.
@@kamX-rz4uy Thanks. At time 5:17, I'll agree that the motor housings look like they are tilted a small amount, but the turn is too shallow for me to tell what I am looking at. One thing is for sure, if the motor was affixed to the wheel hub, like I am suggesting that they do in a redesign, then they would not need to make such a complex mechanism (covered in the majority of this video) to compensate for the wheel moving up/down independently from the motor which is clearly locked from moving up/down (hence the need for their goofy planetary) which is why it seems logical that the motor is also locked from angular motion too and that it is basically just bolted to the car's frame. The boot that you say "covers the connection", is egg-shaped and looks like a regular CV joint cover. Also, I don't see any bracket holding the motor to the wheel hub assembly. The motor housing has to bolt to something that does not rotate to allow it to apply torque to the wheel. It can't be just hanging out there. I'm still convinced that they are still using a CV joint and therefore have designed something that is the worst of both worlds.
In wheel or wheel hib motors have a long history, go back to the Michelin Active Wheel and a Siemens eCorner; More recently Kightyear and Lordstown used in-wheel motors before both filed for bankruptcy, and REE Is going to make small trucks using its motors now that no OEM seems interested in buying the components.
Inboard motors and short drive shafts work fine. These alternatives have to be dramatically better, and it's still an uphill slog to get any car maker to consider them.
In-wheel motors would greatly increase your unsprung mass.
In-hub motors are a no go for full size vehicles meant to drive at highway speeds. No matter how you engineer them , two main factors will always be a problem - available space and weight. Wheel hubs should be as light as possible to reduce unsprung weight, too much of which causes very undesirable vehicle dynamics. Because of the limited space and low weight goals, engineers will have to settle for smaller motors and have more limited gear ratio options. You’ll also have to have all the motor cables run from the hub to the chassis which exposes them to harsher environments than if they were exclusively within the chassis.
Nice work guys! Hope to see this in production cars soon.
I just wanna know, how to cool down and lubricate the gears ? How to seal the giant open gap and keep the shaft movable under extreme conditions such as water, dirt and rocks.
Like you do regular cars. A high strength rubber cover.
@itsjustnopinionok
Except the input shaft is spinning and the housing where the boot would have to attach isn't.
@@itsjustnopinionokcomedy
All the allowed motion is in one plane. How is steering accomplished?
They are either going to have to have the motor swivel with the wheel (which would take up too much room), or use a CV joint, though one that is possible smaller, lighter, and needs less up and down range. (It's at higher angles on the CV where efficiency is lost).
@@mychaljwit seems like they do both in this concept, there’s a visible (CV?) joint and the motor swivels as well.
It seems like a lot of effort to reduce the number of joints from 2 to 1 per wheel and the maximum joint angle without completely eliminating either one.
It probably will still be worth the space savings and modularity, but IMO the success of it hinges on how compact they can make the mechanism that turns the whole motor/shaft assembly while maintaining strength and accessibility for repairs.
I’m all for a redesign of traditional approaches so best of luck to the team!
Well, since there are independent motors, it would be possible to steer by having the outer wheels spin faster than the inner ones. Although, I guess it wouldn't be the pinnacle of efficiency (or safety).
@@nosmermo Like a bulldozer? Lol. Wouldn't be very good on tires!
@@mychaljwWell, yes. But also like the rear wheels of pretty much every car (that doesnt have a blocked diff). But I agree, not the best solution at all.
Humvee’s use a gearbox at the wheel, very interesting engineering feat. My biggest question is how you seal that input shaft through its range of motion? followed by how is it lubricated? I would assume a serviceable gear oil fill of some form? I don’t know why I’m asking as if I’m going to get a response 😂
HMMWVs (Humvees, and civilian Hummer H1's) have geared hubs for portal axles. There are other vehicles with portal axles (mostly older than the HMMWV) and lots of heavy trucks with geared hubs just for more reduction. It's not much of a feat, but it is interesting to see.
I agree that sealing the sliding entry panel would be a major issue if this were ever actually considered for production.
This isn't a portal axle in the sense of a solid axle or independent like hummer.
Further they do not mention lubricant or dust boot concept. They have not thought this far or maybe it's still being patented. Its huyndai they are not fools.
I can see this working at low speeds where heat doesn't play a role and it will probably be OK with flat surface and things like steps.
@@brianb-p6586 el sellado y lubricado del sistema no sería demasiado inconveniente.. con una buena grasa para engranajes, y un buen mantenimiento,, puede durar años... La junta tipo fuelle , al estilonque usan en los palieres actuales podría valer... Lo malo la corrección de las variaciones en el sentido axial...
ruclips.net/video/3-Th5yKxVBg/видео.htmlsi=tgJ_YapVEqQG8SM-
A few days ago, there was a technology presentation in Korea. They said that lubrication and cooling are currently being tested. The biggest key is steering.
So, first of all, it said that they plan to apply it to the rear wheels next year.
I see it as a very interesting concept, but I think it creates more problems than it solves. In my opinion there are lots to solve: sealing between the axle and the hub, between the outer drum and the hub. Also having the motor turn with the wheel seems simple but it's not: you need to align the motor with the steering angle of the wheel and at the same time to separate them in the vertical direction, so this needs an additional mechanism with probably lots of parts. The steering/pivot axis of the wheel/hub assembly changes as the suspension is compressed as does the camber angle of the wheel. Also steering response would be worse given that the motors need to pivot/move when you turn the steering wheel, it will behave as a sort of flywheel. A better solution would be with the cv joints but that still has the sealing issues.
Regarding power efficiency: the torque is transmitted through 5 gear pairs, in comparison in a Tesla Model S drivetrain you have 2 gear pairs, so I think efficiency will be much lower because of friction losses in the gears.
Efficiency would be greatly improved. Torque load on any motor is significantly reduced, this translates into a much greater amount of usable drive torque ie: torque/power that the actual tire can apply in the direction of movement to the ground. (A smaller motor turning the uni wheel can achieve the same speed as a much larger one turning a standard wheel)
@@Howya_fishbin For Tesla model S the gear ratio is 9.734:1 or 9.325:1 according to wikipedia. Uniwheel has about 6 maybe 6.5 measured on the screen, even though I know this is not precise, the gear ratio is far from 9. Also don't be fooled by the many pinion gears, the gear ratio is defined by the sun gear and ring gear.
@@s_attila It is important to consider that with the internal hub the gear ratio can be increased virtually "infinitely" 😉. Further, the gear spins so that torque is applied to the inside of the wheel much like a track drive. With the internal gear and the "track like" setup torque load can be reduced to practically zero. Something to consider....what if a hydraulic motor were to turn the planetary gear set? This would again result in more usable power while lowering any input of energy needed. Also a hydraulic motor would eliminate the necessity for any cv joint as there is no mechanical connection...only a hydraulic hose. 😄
Haha, another note....a hydraulic motor turning the uni wheel can achieve much greater power with significantly less weight than say an electric hub motor.
@@Howya_fishbinyou can't be serious with all this nonsense, you must be a troll 😂
@@s_attila It's gotta be about money then, eh ....?
Even if it's not strong enough for regular cars, it would certainly work in many other smaller applications.
Proud to own a 21 Elantra, part of a company making judt insane strides in innovation and technology seemingly unlike any other manufacturers
That is a bold new concept, which shows great promise. I look forward to seeing how it turns out in Production and real-world use.
Waiting for Jason from Engineering Explained on his honest thoughts on this new drivetrain design.
Give it some time. He's currently breaking down all the equations, pros and cons. And when he's finished his hair will be grayer than Einstein himself lol.
FANTASTIC.......and now I waiting for the e-STARIA whit U-WHEEL......THANK.....
If this survives roads in India. That would be awesome.
Lets hope all of that innovation isn't undone by building SUVs instead of cars...
Is it only me or it does somehow resemble the Unimog’s portal axles, hub reduction and torque tubes concept back from the 50s?
The Unimog introduced in 1948 and still in production) and the better-known (in North America) HMMWVs (Humvees, and civilian Hummer H1's) have geared hubs for portal axles. There are other vehicles with portal axles, and lots of heavy trucks with geared hubs just for more reduction.
None of these geared hubs allow the input shaft to remain stationary while the suspension moves, which is the novel feature of this Hyundai design.
how are they gona lubricate these gears with the motion needed for input shaft and rotation of the outer wheel?
That's the question on my mind. They will have to isolate the gears from elements and debris of the road.
“how are they gona lubricate these gears” - No way. The first three years, while the wheel is under warranty, it will not have time to rust and pick up much dirt, and then it is the owner’s problem, your problem.
If this gets adopted, it makes me wonder what performance aftermarket applications will have to do to beef these up to take more power.
Wouldn't a hub motor still be the better overall solution? Especially for "normal" cars that don't need loads of power and could use smaller motors. Less moving parts, simpler and maybe less overall weight, but with the penalty of more unsprung mass - which could be offset by not using only-for-looks ginormous wheels (who needs 21s on a family SUV?!?)
Gearing is the most limiting factor right now. It's easier and safer to make a high speed EV motor to compensate for the gearing than to make a motor that draws enough amps to start from a stand still with 1:1 gearing at any amount of briskness.
@@Mark_Proton you are right for direct drive motors, but you could use a planetary gearbox. Adds weight, but can be very compact and the motor could be smaller. But I‘m only an armchair expert tbh., not an automotive engineer.
they've nearly acomplished exactly what you're suggesting. the difference between the hub motor as youve described and the uniwheel is the unsprung weight of the motor being shifted into the hub vs on the frame. There is an efficiency loss caused by shifting weight to heavier wheels as well as a bumpier ride.@@meltdown78
Hub motors increase the unsprung weight quite a lot.
@@meltdown78 I foresee heat dissipation issues with a gear hub motor, on top of the obvious unsprung mass.
Take it a bit farther and put the motor IN the wheel and get rid of the drive shafts altogether. Think "Unique Mobility Corp" in Colorado.
All good in a clean lab, but the real world is a gritty place. Good luck!
Great idea, but how does this brake? No word about braking performance
Traction braking.
While regenerative braking can be expected, the vehicle will need a braking system somewhere in the drivetrain. With gears in the wheel hub, the open question, where are the brakes?
@@michaelstafford648 Traction braking. Adding a parking brake is trivial. Believe me, you are not outthinking Hyundai's entire R&D department or thinking something they haven't thought of.
Interesting. At a glance, they need to solve durability and repair costs because if anything takes a punding in a car... it's the wheels.
How does the input gear/shaft stay centred and not fouling on the housing when stationary? I get the it will naturally centre once the wheel starts spinning but the moment it stops the weight of the car will guillotine the input shaft.
Presumably they're still a suspension arm probably with coil springs pushing the vehicle away from the wheel while allowing vertical travel.
@@skierpage These springs must support the weight of the entire car.
I have the same question
Ok, so this is awesome for the up and down motions of the wheels. Is a CV joint still used for turning? I have more questions but so far this looks REALLY promising :)
If you look at around 5:17 you can see a single CV joint on the front axle. You can still place the motor much closer to the wheel because you don't need long driveshafts, just a single, small CV joint. And as far as I understood this also replaces the transmission - putting it into the wheel and saving space.
You can see a joint (@4:20) is still used in the video attached to individual motors with a short shaft. They also claim they have passed the first round of testing @4:47. One would think turning was involved.
@@techpappee "OnE wOuLd ThInK"
No shit Sherlock. I saw the CV joint. However, the way they are going on about not using them, they make it seem as though they wouldn't.
As for testing, it doesn't mean they did the testing in road vs simulated environments in a lab.
5:12 shows that the motors pivot with the steering assembly, staying perpendicular to the wheels.
More complexity in the steering assembly, then, but they apparently judge this to still be worth the improved system-level packaging requirements?
5:12 shows that the motors pivot with the steering assembly, staying perpendicular to the wheels.
More complexity in the steering assembly, then, but they apparently judge this to still be worth the improved system-level packaging requirements?
This is a really great video. The quality is so good. I feel that Hyundai Motor Company is growing steadily in terms of technology as well.
It does look like smaller parts are involved, so manufacturing costs and durabiluty will be my concerns… But fantastic ideas, really hope more testing will be done
Excellent concept. Hope it's a reality in the near future 🎉
Iam at work ... in ZF and constructing the CeTrax2 ... saw the video and think .... nice work ! 😊😅
So where do the brakes go? or are they using the engine as the brake?
Don't need brakes when crashing would generate billions.
All wheel drive!
Yes, awesome korean engineers!
When a traditional system car goes over potholes, the motor and all of its moving parts do not get a lot of shock, it is absorbed by the wheels, and other dampening parts (I forgot what they are called).
This new construction, it seems like it will be getting a lot of that shock and possibly break down too.
And I don't doubt this construction doing well for 1-5 years.
Can it survive 7-12?
I think it is for a good reason that such complex part as the engine or car motors are getting the same protection from shock that the driver gets. It is intricate and susceptible to costly repair if it wasn't.
That is my concern despite me being very excited to see how it works.
Well this is NOT in-hub motors; the motors are still in the chassis... they removed the brakes and added the reduction gears into the wheels
Now there is a hope in the automobile industry. I was always wondering about why the designers does not give a touch for a better automobile drive experience.. it was always about exterior design which they care and some minor interior details. Even EVs were after that.. However the drive itself was not considered as an improve area element. Whatever... I am veeerrryy happy to see that it is now the time. Thank you Hyundai❤❤❤
Teşekkürler HUNDAİ.
Extremely awkward copywriting but very interesting technology 👍... hope it succeeds.
ECCELLENTE, BRAVI 👍👍👍
Oh boy it looks and functions like some college kid's senior design project.
Very interesting, but I wonder how they intend to integrate brakes into the system.
I want that cool wheelchair!
Hyundai , this idea would be a great benefit across your production range / car , bus and truck Battery Electric Vehicles .
A cool concept but seems much more complicated than ordinary shaft drive. Also, it has more moving parts. Thus there are more things to break down and it's more expensive to build. Also, it increases the wheel's unsprung mass which is also not a good thing.
This is a modification of the in-wheel motor design. So drastically reducing the unsprung weight and eliminating the motor's exposure to shocks from potholes. Although, yeah, more unsprung weight than a traditional wheel, but I don't think unreasonably more.
That's true for every significant change in the history of the automobile.
Remember in this case they’re moving the reduction gear and final drive to the wheel hub so the parts count is virtually identical vs the traditional CV joint setup. It’s modular and easier to service too.
@@starrwulfe are you sure it won't end up as unserviceable self-contained wheel assemblies where you have to buy a new one every time something goes wrong?
Near future will show the truth. Like the creativity to push the limits.
That's a clever linkage!
How is the dirt, water, snow, gravel, etc Kept out of gear/hub area? I see as the only area that could real hurt this design.
Another intriguing bit of engineering. What I want to know is when both this Uni Wheel and the IMA platform will appear in Hyundai's EVs.
Timelines in the auto industry are loooooong
@@GGoAwayy It broke cover already so they've got the patent already... 🤞
interesting idea. Personally, I expect a lot of unpleasant noise emissions due to the gearing and the very high speed of some components. These speeds certainly also limit the overall usable speed, 120km/h in the video. Another issue will be the sealing of the mechanism and the total number of parts of the mechanism >>> potential failures. The total weight of this device will probably not be negligible either (unsprung weight). And lest I forget, does anyone mind that the vehicle has stopped turning? Or was I looking at it wrong?
Hey! Not a word about the braking system for the vehicle?
My guess is that it will either be inboard or they'll minimize it as much as possible and expect regen to be able to pick up the slack, which it can't do in all conditions.
The tire spins around the wheel so no unsrung weight issues.
Doesn't the uniwheel limit the suspension travel to its own diameter?
basically, in between traditional driveshaft and hub motor.
It all goes down to difference in unsprung mass and costs/reliability.
Hub motors almost certainly win on the latter. Not sure Uni Wheel is winning on the unsprung aspect either.
Not going anywhere, anytime soon.
And, I think I can do better! :-P
Would this be able to tow anything? Seems like that would be a lot to ask of those little gear cogs to pull a few thousand pounds of boat or camper or whatever in future vehicles
It's not that much different than what's in your differential or your transmission
2:55
I see something that looks almost like a CV joint on the right, but it's gone in the next shot?
Protean goes one step further and has the motor as part of the wheel, which is an even greater step. The argument against it would be the larger unsprung weight of the wheel, but one may argue that city travel means hopefully fewer potholes to contend with. Those solar EV challengers with PV roofs all had motors in wheels.
If this works, it'll revolutionize the off roading world
Individual control of torque to each wheel is claimed as an advantage as if it has anything to do with this design, but it does not. One-motor-per-wheel works with any motor location and shaft design.
Amazing innovation! Simple and elegant.
"Simple and elegant" - Simple? Where did you see “simple” there? From a really simple and cheap wheel they made a complex monster with 11(!!!) gears. Let them voice the price of such "simplicity".
Except plantary gears don't last spining at high speeds the bearings don't last
When I see Hyundai slap this baby into their armoured vehicles, only then I'll be certain they trust in the design longevity.
Love innovation.
Would it be possible to also get rid of the conventional brakes and incorporate all braking into the drivetrain? Brake rotors that rust and brake calipers that seize up from corrosion is a major issue where roads are salted during winter...
凄いですね！！日本以外で頑張って！
Until now when you hit a pothole you might have to replace your wheel or tire from now on if you hit a pothole you have to replace your whole drivetrain the future of car driving
Really superb invention
Interesting!😃
So, why not just use the already existing hub motors that i see in things like the Onewheel? Can that not be scaled up? How is this more efficient than that?
Hub motors on full size vehicles, or ones meant to drive at significant speeds, would suffer due to the large amount of unsprung weight, and having the motor and the gear reduction on the hubs limits either the available ratios or the motor size. Splitting them offers better handling and potentially more power from larger range of motor choice.
I like the concept.
Interesting. We will have to see if this system can gain traction.
Any mode of transportation, as long as its a car. BTW. Whats the weight? It adds to the unsprung mass, quite a bit.
what happens when it bottoms out? CV joints suck to replace. are they price-comparable?
Makes sense for rear wheel drive but how do the front wheels steer ?
It seems to me that this design although possibly revolutionary, adds complexity and many more parts compared to a cv joint
wish they showed how it turns
Yeap, good question
What happens to unsprung weight in comparison?
Did I get it wrong ? its inside the wheel , not a part of it , therefore its not rotating with the wheel making the actual wheel heavier / harder to move . I think thats what is happening . I could also be wrong but it appears to have less mass in general then with regular drive shafts etc so gross weight is reduced . I could be wrong again but although not increasing rotational mass being directly inside the wheel whatever mass it has is directly OVER the wheel / s which I would assume on some level helps plant the wheel via its weight and the mass is evenly distributed over 4 wheels for instance further increasing AWD ability to transfer power compared to RWD or FWD and purportely you dont have fluctuations in torque delivery with the angle changing etc so less drivetrain loss and all of those would seem to mean better acceleration from the power availible / no waste , as is the case with transmissions going to differentials etc that all "eat " power and why HP is rated at an engine ( potential power) but also measured at the wheels to know how much actually makes it to the wheels . Having each one independent also means super duper torque vectoring which means even less likelyhood of spimming the tire which turns HP into heat and smoke without full use of power to move car as well as reducing tire life . The movement they show would also suggest better contact patch when surface changes putting less pressure on tires in different situations which would mean longer tire life even if driven hard instead of eating up outside of tire etc to where you have more tread on part of the tire but once you remove more tread in a specific area you reduce traction / performance and would need new tires despite some section of tire being in good shape with use left . Everybody who drives fast or hard , had alignment issues or set up a car a certain way has had to get new tires despite a good section of the tire looking and being good and that is a drag , you might try an wait to get more miles but you lose a bunch . Regular ICE AWD cars even have issue if 1 tire has significant wear compared to others changing diameter which throws off the gearing / differentials meaning needing to replace tires so all are even or shaving a new tire to be same diameter ( throwing away brand new tire reducing miles it will be useable) . With NONE of that and truly independent wheels that is no longer a concern or less concern as each wheel optimizes for its tire even if slightly different then the others . If those gears are strong or strong enough for whatever power will be put through them it looks to be a win , But real world is real .
Where did the brake disc's go?
Holly unsprung mass... And could you imagine the meshing noise? What about the brake rotors/disks? Are they going to be inboard?
Looks like a perfect solution for a problem that never existed in the first place...
スゴイの考えたね！
あとは、埃が入らない様にするのと潤滑と冷却の問題だね？
歯車を沢山使うから、デフギヤみたいに油漬けで回さないとダメかもね？
ソレと・・・結局CVジョイントは使うのね？
Cool concept, but how many times does a UniWheel have to be replaced? Have they even driven it 100K miles on it?
Wouldn't a Schmidt coupling make more sense in this application?
I am far from an expert, but this sounds like something that should have stayed as a back of the napkin drawing.
There's no free lunch. Such a system will have much higher unsprung weight, and would behave worse over bumps. Also, it may have a higher rotational mass, making breaking and acceleration slower, to some degree.
Sorry folks, this is not viable. The pinion drive train would need dozens of bearings, each that would spin so fast their packed grease would fly out. Since you can't use grease, then you need hydraulic fluid. Anything other than rotational motion is basically impossible to seal, so the suspension gearbox itself is not viable. Also, no animations were shown on how the wheels turn left or right. The gearbox does not appear to have any freedom of movement in the direction of a turn.
Also, since wheels are no longer coupled and driven from a common power source, if one motor or drive train should fail, the car will pull to either side which is a safety hazard. The flip side to this is also with breaking. This could be overcome by smarter software, but mechanically linked drivetrains don't require software to work right and reliably.
The most optimal solution is to design the motor field coils themselves to be embedded directly in the wheel hubs. Beneath large ships they are already doing this with their articulating propellers driven by very large coils in the surrounding enclosure. The propellers essentially spin on bearings in the the center. The torque comes from the coils directly on the outer diameter of the propellers. If you are going to put a motor on each wheel, might as well put it right in the hub, then you completely eliminate all gearing, and drivetrain. Think of each wheel like a beefed up brushless fan motor. Motors can be made to do this for torque or speed, but probably not both unless you could find a way to reconfigure the battery packs from series combinations of cells into parallel combinations. Parallel combinations would be used for large torque at startup. Series could be used for fast speeds on the freeway. You need the extra voltage to counteract the back EMF from the motors spinning increasingly faster.
Regarding the problem with unsprung weight added to each wheel, that's mainly due to the jarring effects of pot holes and other serious vibrations. Mount the motor coil in each hub, but make it be a planar orientation with built in shock isolation. In other words, put all the complexity of that gearing mechanism into a relatively complex motor suspension system built into the hub. Free to move up and down, but not spin. I don't know why nobody has tried or even touted this yet.
Sometimes I wonder why engineers over-complicate stuff...
Hey look, Hyundai rediscovered portal gears. We've had this tech to some degree since the forties.
The percentage of increase in efficiency remains unrevealed, indicating that it may be a small figure. However, the space saving property of this technology is indeed very innovative and I look forward to seeing it integrated in new vehicles. Hopefully not just in South Korean vehicles. Considering the global automobile theft statistics, waiting for Kia/Hyundai to perform an overhaul on their anti-theft systems before purchasing one of their vehicles, may be recommended.
And it seems to be cheap to replace when damaged. Interesting.
This is the killer application. No computer inside.
I am hopeful for this technology to be developed for mass applications if it can be proven (efficient, reliable, durable, ...)
But don't know if it will be better than wheel/hub motors. They too will continue to get better.
golf carts gonna get wild
Kentucky and NewJersey highways are saying HELLO to the uni-wheel
A BIIG HEELLLOOO 👋👋
😂😂
"Consistently satisfactory"
Amazing!
How much energie does the gear train in the wheel cost? Is it less than the CV joints?
Great presentation.
@hyundai motor group, why not move the electric motor to inwheel? Seems only the drive is moved. What challenges you faced moving the electric motor itself inwheel? If motor is inwheel, the whole thing could be evolved to drive-by-wire.
What would be the advantage of that?
@@uku4171Fewer moving parts.
GREAT IDEA
This concept is Genius what about the unsprung weight
They should just invert the implementation. uni wheel on the inside. less complex moving parts and unsprang weight on the wheel hub. with the current design with all small worm gears and pivots, linkage transferring huge torque. Hyundais will have to increase roadside assistance.