If you enjoyed this suspension video, here are a few others you may find fascinating! McLaren Doesn't Use Sway Bars - ruclips.net/video/8AVBddY8ClM/видео.html Ford GT Has Two Spring Sets - ruclips.net/video/L0rAU0or3rQ/видео.html Honda Civic Type R No Torque Steer - ruclips.net/video/Gw5-lVlzNoY/видео.html Thanks for watching and have a wonderful day!
Question for a video: Why don't we design cars that have their roll center above the center of gravity so they roll into turns, banking like an airplane? Would the geometry required mess with camber and scrub? It seems you'd just have A-arm suspension with the long arm on top, yeah? This has been on my mind since I designed the suspension for the University of Portland Mini Baja in 2000.
My guess is it's an issue with packaging. On a race vehicle, this isn't as critical compared to a road vehicle of the same track and wheelbase that requires room for several people to sit in.
This technology is pretty awesome. A lot of pro race cars have manually adjustable sway-bars to adjust grip for certain track/surface situations. So, the driver can change the sway-bar stiffness while racing, amazing!
it's not the same thing because with this system while going straight and also when you're just cruising and not pushing the car you have very soft sway bars and the suspension can articulate freely, but if you suddenly go for it or simply get into a turn way too fast the computer will automatically increase the stiffness as needed. so you get the best of both world on the fly with no driver input. well at least in theory, let's see how good it will work in practice. let's also see what's gonna fail first. these things will make terrible used car purchases. just another system and host of sensors to fail complicating everything. soo german of them!
The Vibe I think the same every time I see a new automotive development. I think to myself "please don't be an electronic solution, please tell me it's a mechanical device," but that's obviously unrealistic at this point so then I default to "at least tell me it's a simple feedback based analog circuit and not some proprietary processor they've added to some mechanism PLEASE!" but sure enough it always is some proprietary chip that will be borderline impossible to replace when the whole thing shorts in a few years. I miss when there wasn't a chip for valve timing, braking, steering input, throttle control, compression ratio, etc. but I will just have to convince myself performance and safety are fair trade-offs for reliability and resale value.
Wow its an amazing system, btw after I watch this video I just realize that roll bar could affect a car behavior. Used to play a Granturismo game and in that game there is an option to adjust a roll bar, but I'm adjusting it randomly and not knowing what will happen lol.
It is, Jason make me really understand how the roll bar works, and now whenever I play the game. I'll adjust it carefully and make it balance as Jason said as possible.
Another benefit is that a stiff sway bar affects straight line comfort. So they can relax the sway bars when cruising so the wheels can articulate freely and you feel less bumps, then tighten up when you're in corners. Then on an S4/RS4, they can incorporate more bias to the rear in sports mode to help it feel more tail happy. a win win win (etc.) in my book.
According to Audi's media marketing material... the vehicle unladen weight is 2.3 tons - gross weight limit is 3 tons. This thing is going to be a tank!
To be fair: if they such a suspension work with that amount of mass they practically have it tsted for lighter vehicles as well, this system in a performance car with a gui to modify the settings would be nice, maybe a scaled down r8, call it r4, put either a 4,6 or for e nostalgia 5cylinder engine in it and price it competetive, should sell well
Hmm 5 cylinder (twin) turbo with an electric boost system would be interesting, not just for street performance but rallye as well but im not well versed in the current rallye specifications for any kind of rallye
Citroën had a hydraulic version of this over 20 years ago on the Xantia Activa...still a great system though ;). And for some reason Citroën abandoned it years ago too...
Yeah, but the Xantia already had hydraulics anyway ;). An Activa was only 17kg heavier than a normal Xantia, for a total of about 1340kg for the base two litre model. Besides, high pressure hydraulics could potentially be more powerful than an electric motor (not sure they are here). Of course, electronics have improved a lot over the years, but then there shouldn't be that much to compute here. Just measure a few sensors here and there and stiffen the sway bars accordingly. Not saying it was better all in all, just that there's nothing really new here...
MacMan iPowermacbookprair I agree. Had a C5 back in the days. Best suspension I’ve ever had. Automatically adjusted to the load as well. Genius. Too bad they made it optional.
MacMan iPowermacbookprair the hydraulics are faster, but the control unit is the heart of the process. My dad had a late 70s Lincoln with an early form of antilock brakes. It was a solenoid based system, overly complex, heavy compared to new systems and very slow compared to new systems. On the audi system, it's more than just a few sensors..the car is loaded with them. Granted all these systems have heritage from 20 or so years ago, but they are much more sophisticated, less expensive as a percentage of the value of the car, much more reliable, although the first "New" generation of anything I tend to avoid. Some never catch on...remember the big rave of 4 wheel steering in the 90s? Never made it past a few vehicles
The c5 never had active sway bars though, but they were nice and very comfortable to drive too ;). It did actually have active suspension, just no active sway bars. Unfortunately, hydropneumatic suspension went out of production altogether in june last year I believe :(.
So basically they make a heavy and tall vehicle, put sports car performance in it and then deal with the problems with more technology. I guess that's how they do things today. Not for me, too expensive to buy and maintain. Nice video though!
Either that or they can let it just roll over. I think this is a more elegant approach compared to carrying a jack to right the car after every turn. Plus, the more they make, the cheaper it will be, and then we might get this in even budget cars someday.
Yeah we should just go back to straight axles and leaf springs. Simple and Cheap. Or better yet, Horses. My last horse lasted 30 years before it died on the side of the road.., and It refuelled itself automatically!
Good lesson for those thinking about fitting after-market roll bars just because "its supposed to be better". Balancing a car is not easy. Going at it "brute force" may change its behaviour, making it unpredictable. Just remember Senna's car in the first year at Williams, with terrible unpredictable mid-corner behaviour changes - and there were F1 engineers working on it! Not an easy task!
I put a stiffer sway bar on the back of my celica to counteract its understeer for this exact reason! Worked like a charm and its so much more fun to handle now
That was a nice presentation. However, I couldn't help but thinking, "is this expensive technology really necessary for a grocery getter?" I really don't think so. But the Audi Brand is all about pushing technology/engineering to its limits. Sometimes it works great but when it doesn't the customer is stuck with a gigantic bill😕
Another thing to bear in mind is this is on the SQ7, which is the sporty version of the giant SUV. I can't find much info on it, but the base model Q7 starts at 50 grand, and I would bet that the electronic sway bar isn't standard equipment. On a car you can spec up past $100k, you can expect to find tech options that aren't necessarily practical or economically feasible, never mind that its durability is largely untested in the real world, but if you're spending that kind of money on a car you may be interested in the bleeding edge of technology, which this version of this system appears to be. It's probably not a box most people will check unless a) they want to do sporty driving in their 3 ton AWD children carrier or b) they want to get the price as high as possible for bragging rights ("Oh yeah? Well, I specced my Audi SQ7 up to 3x its sticker price, because I'm RICH!").
That is an excellent point. I would hope that by the time this tech trickles down to the Nissan Z or Toyota 86 of the future that they've figured out either how to make it not break, how to fix it cheaply, or both. If the engineers can't make one of those two things happen, the people who decided which equipment goes in which models and trim levels wouldn't be doing their jobs if they allowed it into a car that would be totaled from a failed anti-roll system.
Yeah, it's pretty simple like that, the systems that can't be solved reliably and cheaply just don't end up going into the cheaper cars. Plenty of examples of such systems in the past as well. But you can't succeed if you don't try.
Land Rover created the ACE system in 1998, doing the same thing here but with hydraulics rather than electrics. It worked incredibly well, and in my 1999 Discovery 2 it is still working very very well.
Have you ever heard of the Bose Electromagnetic suspension system that came out in the early 2000s? If so, what do you think about it? They showed footage of it literally leaping over something they placed in the road. Pretty sweet!
Nice video! This reminds me of the time, when Citroën took their trademark Hydropneumatic system in the late 1980s, added a microprocessor control system which resulted in the creation of the Hydractive system and it eliminated body roll altogether. And now there is their new system the "Citroën Advanced Comfort" in the new C4 Cactus - I didn't have the honor to try that one yet.
Csuzdi Gábor Hydractive is just about variation of stiffness in the suspension. The body roll is another system called Activa. Sadly these types of hydropneumatic suspensions have been remove from Citroën cars after the C5.
Another (although not ideal or probably even possible) way to eliminate body roll is to adjust suspension geometry such that the roll axis (line connecting the front and rear roll centers) passes through the center of mass.
It's really neat that the computer technology/control has finally caught up with the physics of production cars... remember the Williams active suspension F1 car in 1993... banned instantly, of course. Thanks
Active roll bars make a huge difference. My BMW has a similar system, except the hydraulic couplers use pressurized power steering fluid. You can corner at ridiculous speeds and the car stays perfectly level.
I don't know.... it just looks like Audi has added something that will break eventually. So many things to break and go wrong on a car these days which is sad.
I always wonder why people say this. Do you not realize you just commented via a very advanced piece of technology? How often does that break. An engine is more complicated than this system, yet there are engines that run over 500K miles without problems.
Duskconqueror If you buy the best car you can justify based on your budget and the most random thing happens to it the average person has undue strain to pay for it if they have no factory or extended warranty. It's gotten to the point where if a car is financed for longer than the warranty lasts I can see banks requiring full coverage for maintenance or breakdowns. Just like with health care most people cannot handle the costs of even a relatively minor failure on modern cars especially if they are making payments too. So they may be more reliable for their complexity but tell that to a college age commuter when they suddenly and unexpectedly have to pay several thousand just to keep the car on the road. Many will just let the car go back to the bank.
Duskconqueror What a moronic comment,we have all seen those 'what if a car was a computer' comparisons. Have you looked at cars of the last 20 years? The jury is in. They break and are crazy expensive to fix. It is great technology for race cars. I will just deal with some body roll.
Love your videos, but for whatever reason, for me, the first description of how the system works (upper left of the whiteboard) seemed more confusing than your usual explanations. I'll rewatch it a couple of times and see if I missed something.
It will surely make cornering at the limit interesting, as the sway bar torsion adjusts so vastly, while still having a fixed or progressive spring rate.
BMW 7 Series calls this Active Roll Stabilization. Its just an Electronically controlled Sway Bar(s) located in the Front and Rear of the vehicle. It does make a big difference in countering centrifugal force/ Body lean.
Land Rover has been doing this for a while in a hydraulic application which in my opinion would be much more powerful than an electric system. My 06 Range Rover Sport Supercharged has the dynamic response hydraulic sway bars and corners extremely flat for its weight.
You should discuss the 1991 UZZ32 Toyota Soarer, that was actually innovative. Or even the Xantia Activa (have owned both of those cars). All VAG have done here is look at systems that BMW and Land Rover have designed over a decade ago, and made it more powerful, must have been so hard for them to come up the idea...
I would actually love to experience this. My ‘08 pilot (obviously) has a lot of body roll and a rather harsh ride since it’s so old. I have never really been in a car with very little body roll
Come to Europe and experience the world record holder: Citroën Xantia Activa. Zero point five degrees body roll. Beats any production supercar since 1999. Yes. It's French. I own one since yesterday and boy ... I'm not lying,
Handling balance understeer : oversteer is one issue. So presume a '70s or '80s front engine rear drive. If you make the rear stiff enough to get a nice neutral balance at mid corner, there will be a lot of weight transfer on the back axle, so as soon as you start to try to accelerate, (with your stock open centre dif) you get bad inside wheelspin. A much stiffer front swaybar is about 1/6th the price of a good limited slip centre. If you were tuning a car on the cheap, when I was young, you'd go very stiff on the front bar. That gave some understeer, but the bodyroll was much reduced and the power-down off the corner was dramatically improved. It did not in every way result in a car that was nicer to drive, (horrible understeer) but it sure as hell was quicker....
Man, done decades ago, google Citroen Xantia Activa, zero body roll, so zero, it had to use special Michelin tyres, over side wall reinforce. No need for a shitload of electronics and yes it had a suspension computer and 6 piston high pressure LHM pump. Ok, this system is different and obviously more advanced. but imho, more prone to problems.
Actually the system is developed and build by Schaeffler. Every electromechanical roll bar from other cars is build by them too. BMW for example uses a 12V version in the 7 Series, which has a similar design.
Interesting Video...: would you mind doing a Video talking about ALFA ROMEO Suspensions? I am from Italia and in there ALFA always had the reputation of making the most stable Cars (they share some their Suspension Tech with Ferrari) and it's all thank's to what they call the "ALFA LINK" also known as the "Sospensione a Quadrilatero Deformabile" ... It is interesting that for a number of years rhey used this Tech even on front wheel Drive Cars and they were unbeateble in Stability Tests (yes: even BMW can't match it). I have owned two ALFAs (a 159 and a 147) and i never drove any other Car as stable as those. Now the newly introduced 'GIULIA' has an evolution of the Suspensions i had on my old ALFAs and i wouldn't mind understanding more of what their secret is in all that witchcraft of Torsion Bars and Beams that make their Cars drive like they are on Rails. Thank you
Yes they did, and the Xantia Activa V6 is still the car with the fastest speed ever at the moose test, and the video is almost shocking: It has absolutely no body roll, which makes it look like the car is going over that corner casually. The Bose system might have been even better (seriously, it's so impressive the demonstration video almost looks fake), but sadly never was in a production car.
Hello Jason, I really learned a lot about cars by watching your videos. Can you please make a video about "Should you park in gear when in an incline for manual transmission cars?" This was taught to me way back in driving school but I didn't really believe it because it doesn't make sense that it prevents your car from rolling down. It would be very helpful if you could explain it similar to should you press the handbrake button. I'm really curious if this is real or a myth. Thank you.
Hey Jason, I've got a question for you: while watching the last Formula E e-Prix, I noticed that the drivers, while reaching a corner, released the throttle pedal way before they hit the brake pedal, in order to harvest energy via the regenerative braking system. However, the graphic showed that the energy recovered in the period in which the driver was moving without touching any pedal was way lower than the energy recovered during the actual braking phase. Could you explain exactly how braking works on FE cars, or electic vehicles? Thank you, love your work!
This process sounds awesome if it is highly efficient but I wonder, how much would a system like this cost and how much to maintain or replace. It would be nice if they had setups you could add to other vehicles and programed.
Well I still think the best way to reduce body roll is getting a proper car with an acceptable weight and a CoG which is not up there in the clouds, but as far as lumbering 2+ ton wheeled tanks go, thi system is pretty nice. The most interesting part of the video though was the explanation of the effect of wheel load differences on understeer.
I dont understund : with stiff front and more load on front out wheel i think that will increase friction on that wheeland give a good reactivity in turning
Land Rover's Dynamic Response (available in Range Rover and Range Rover Sport since 2013) works exactly the same way. The whole system was developed by Bilstein in the early 2000's, actually the previous generation of Range Rover already used something like this but not so advanced (it had only one channel, so both sway bars were actuated at the same time).
This reminds me to put some bolts back into my rear and possibly front duel swaybar setup I really should lock them some how because thread locker and nylock nuts don't work, maybe wired nuts..?
BMW had active stabilizers like 15 years ago, for example on E50 545i, not electric but hydraulic and it worked amazingly well. Now the problem that is obvious with Audi is the heat, how they are cooling the electric motor, obviously they are not, but if one drives like mad trying to go sideways non stop for like an hour this will overheat and give out.
To expand on this topic, you should do a video on the latest Range Rover Sport SV and it's 6D Dynamic Suspension. (Also ties into McLarens crosslinked damper system)
Great video. This is probably great technology for race cars, but have you looked at cars of the last 20 years? The jury is in. These technologies break and are crazy expensive to fix. I will just deal with some body roll.
Instead of correcting body roll (keeping the vehicle level), can an active roll-bar system be used to cause the vehicle to roll into the corner, transferring more load to the inner wheels resulting in better traction and tighter cornering?
There is a simpler method to prevent body roll that they could have implemented. Many sports cars do it. Looking at the car end on: Imagine the wheels as just fixed on the ground. Somewhere above the center point between the wheels is the "roll axis" of the car. This is what the car body rotates around as it leans left or right. Picture someone pushing the center of mass to your left. Their ability to make the body roll depends on how far above the "roll axis" they are pushing. If the roll axis and center of mass are at the same point, there is no roll. The anti-sway system then only have to deal with the tendency of the body to rock side to side if you hit a bump with the wheel on one side.
Thank you for another excellent video. Though I was generally familiar with front and rear anti-roll bars, your explanation regarding how the relative stiffness of the front or rear anti-roll bar can affect under/oversteer characteristics of the vehicle.
In think I'm getting addicted to these videos. I have 1 foot into building my own car. One question if anyone can help: why would a stiff front wheel lead to understeer? Understeer means the front wheels slip, right? Wouldn't more vehicle weight on the front wheel lead to more friction? I don't see it yet...
A stiff front means the front has more work to do. Suspensions want to do as little as possible for optimum traction. The more pressure on a tire, the less grip overall it has. As you overwork the front tires, they lose grip and you understeer.
What are the benifits of arb then I'm going to tell what I understand and if there something wrong please correct it to me; 1.The change in camber decreases as there is no body roll 2. Related to the upove the contact patch will not increase a lot and this will be better for gaining higher cornering forces
The problem with anti-roll bars is that lifting an inside wheel, especially if the car has a light rear end, on a bumper corner is very dangerous. Better to have no ARB and do active damping.
Audis are notorious for under-steering because of their engine and AWD setup. People complain for years. Audi responds with an over-engineered and complicated, electric solution. Well played.
Why not use electronic suspension to accomplish the function of an anti-roll bar? More specifically electronically controlled hydraulic shocks. This would take less space, would not need steel bars running along the axles thus saving weight, and could utilize the same 12V system. Many cars and even the new RZR has electronically controlled shocks... adding the hydraulics pressurization should be an ease.
Really quite like this system! Doesn't seem as simple and durable as the system McLaren used in the mp4-12c (and Citroën C4 WRC). Does anybody know the pros and cons of these systems when compared to eachother?
Such an innovative technology great to see that audi can completely rip off what BMW did in 2007 whilst introducing a 48v electric system that isn’t compatible with anything and require its own battery and electronic systems that won’t stand up to the test of time. Soooooo innovative. 👌
I wonder how this will affect longevity of components like bushings in the control arms, or ball joints. Is load subsequently transferred to them if an axle stiffens up?
My boss just got a 2011 Porsche Cayenne turbo. That thing corners FLAT. Flatter than my 1989 MR2 turbo. It also has enough brakes to pull your face off your skull. All while having a super comfortable ride. I love German Engineering.
Jonathan/Justin/Jasper (I watched your April Fool's video and really enjoyed it), great video, once again! Quick question for you: if it's applying counter-torque, wouldn't it essentially be braking the outside wheel, causing the car to slow down to some degree? Maybe I'm just over/underthinking it but it just seems like the logical thing to happen in my head.
It's not applying a braking force to either wheel, as it's only connected to the control arms of the suspension. It can influence whether the control arm goes up or down, but it cannot impact the driving speed directly.
Engineering Explained Oh! Wonderful, that's what I was missing then. I do realize you mentioned it in the video, I think I just didn't understand it properly. Thanks for the explanation! Have a great day.
@Engineering Explained Most of the OEMs like Toyota and so on, have this kind of tech, normally they use a controller called "Skyhook"，some articles could be found on SAE。 What's more it works for ride and comfort as well.
If you enjoyed this suspension video, here are a few others you may find fascinating!
McLaren Doesn't Use Sway Bars - ruclips.net/video/8AVBddY8ClM/видео.html
Ford GT Has Two Spring Sets - ruclips.net/video/L0rAU0or3rQ/видео.html
Honda Civic Type R No Torque Steer - ruclips.net/video/Gw5-lVlzNoY/видео.html
Thanks for watching and have a wonderful day!
Question for a video: Why don't we design cars that have their roll center above the center of gravity so they roll into turns, banking like an airplane? Would the geometry required mess with camber and scrub? It seems you'd just have A-arm suspension with the long arm on top, yeah? This has been on my mind since I designed the suspension for the University of Portland Mini Baja in 2000.
DWB's vs struts comparison video next please?
blurglide because of sense of balance people have. Or other words... because of puke 😎
Engineering Explained I believe Toyota has a hydraulic version of this with kdss?
My guess is it's an issue with packaging. On a race vehicle, this isn't as critical compared to a road vehicle of the same track and wheelbase that requires room for several people to sit in.
This technology is pretty awesome. A lot of pro race cars have manually adjustable sway-bars to adjust grip for certain track/surface situations. So, the driver can change the sway-bar stiffness while racing, amazing!
Justin's Pit Lane In what car or series? Are you sure, that you don't mean the brake bias?
it's not the same thing because with this system while going straight and also when you're just cruising and not pushing the car you have very soft sway bars and the suspension can articulate freely, but if you suddenly go for it or simply get into a turn way too fast the computer will automatically increase the stiffness as needed. so you get the best of both world on the fly with no driver input. well at least in theory, let's see how good it will work in practice. let's also see what's gonna fail first. these things will make terrible used car purchases. just another system and host of sensors to fail complicating everything. soo german of them!
Justin and I are well aware what an anti-rollbar is. He mentioned this technology in racecars and I'm in doubt about that.
The Vibe I think the same every time I see a new automotive development. I think to myself "please don't be an electronic solution, please tell me it's a mechanical device," but that's obviously unrealistic at this point so then I default to "at least tell me it's a simple feedback based analog circuit and not some proprietary processor they've added to some mechanism PLEASE!" but sure enough it always is some proprietary chip that will be borderline impossible to replace when the whole thing shorts in a few years. I miss when there wasn't a chip for valve timing, braking, steering input, throttle control, compression ratio, etc. but I will just have to convince myself performance and safety are fair trade-offs for reliability and resale value.
Do you have a different conversation? Well, I like icecream but what has that to do with an elevator anyway?
Wow its an amazing system, btw after I watch this video I just realize that roll bar could affect a car behavior. Used to play a Granturismo game and in that game there is an option to adjust a roll bar, but I'm adjusting it randomly and not knowing what will happen lol.
Muzaki It doesnt give you a brief explanation? Not to be that guy but Forza briefs all the adjustments
It is, Jason make me really understand how the roll bar works, and now whenever I play the game. I'll adjust it carefully and make it balance as Jason said as possible.
If you get a chance, drive a Citroen Xantia Activa in real life, and in good condition. Rare but you will be rewarded...
Haha! This is exactly how I learned how I like to tune my cars in reality! That, along with my G27 wheel :) suspension means everything to me.
Sean MacDonald when u said that the first thing came to mind was a Miata
Another benefit is that a stiff sway bar affects straight line comfort. So they can relax the sway bars when cruising so the wheels can articulate freely and you feel less bumps, then tighten up when you're in corners. Then on an S4/RS4, they can incorporate more bias to the rear in sports mode to help it feel more tail happy. a win win win (etc.) in my book.
i love how simple u explained understeer & over steer ...it opened my eyes its so much simpler than how they wrote about
According to Audi's media marketing material... the vehicle unladen weight is 2.3 tons - gross weight limit is 3 tons. This thing is going to be a tank!
shinybaldy hope it's got a cvt to increase mpg
Jeez, that's not far off the upper limit of 3500 KG max gross weight on most UK driving licenses for the car category...
To be fair: if they such a suspension work with that amount of mass they practically have it tsted for lighter vehicles as well, this system in a performance car with a gui to modify the settings would be nice, maybe a scaled down r8, call it r4, put either a 4,6 or for e nostalgia 5cylinder engine in it and price it competetive, should sell well
Typing on a tablet sucks, but i guess you get what i meant ^_*
Hmm 5 cylinder (twin) turbo with an electric boost system would be interesting, not just for street performance but rallye as well but im not well versed in the current rallye specifications for any kind of rallye
The over and understeer adjustment is awesome thanks for this video I feel like you make learning easy and not boring.
Thanks!
Citroën had a hydraulic version of this over 20 years ago on the Xantia Activa...still a great system though ;). And for some reason Citroën abandoned it years ago too...
MacMan iPowermacbookprair hydraulics are heavy, prone to leaks and didn't have the electronics to control the system as they do now
Yeah, but the Xantia already had hydraulics anyway ;). An Activa was only 17kg heavier than a normal Xantia, for a total of about 1340kg for the base two litre model. Besides, high pressure hydraulics could potentially be more powerful than an electric motor (not sure they are here). Of course, electronics have improved a lot over the years, but then there shouldn't be that much to compute here. Just measure a few sensors here and there and stiffen the sway bars accordingly. Not saying it was better all in all, just that there's nothing really new here...
MacMan iPowermacbookprair I agree. Had a C5 back in the days. Best suspension I’ve ever had. Automatically adjusted to the load as well. Genius. Too bad they made it optional.
MacMan iPowermacbookprair the hydraulics are faster, but the control unit is the heart of the process. My dad had a late 70s Lincoln with an early form of antilock brakes. It was a solenoid based system, overly complex, heavy compared to new systems and very slow compared to new systems. On the audi system, it's more than just a few sensors..the car is loaded with them. Granted all these systems have heritage from 20 or so years ago, but they are much more sophisticated, less expensive as a percentage of the value of the car, much more reliable, although the first "New" generation of anything I tend to avoid. Some never catch on...remember the big rave of 4 wheel steering in the 90s? Never made it past a few vehicles
The c5 never had active sway bars though, but they were nice and very comfortable to drive too ;). It did actually have active suspension, just no active sway bars. Unfortunately, hydropneumatic suspension went out of production altogether in june last year I believe :(.
Great video, I watched the Audi video myself and didn't quite understand the mechanical side. Now I know! Love these videos keep it up!
Another great video from my favorite RUclipsr
Thanks Johnson!
This is a perfect example of why the older cars are gaining much more popularity and value.
When you double tap the like button before the video even starts you know it’s EE! Keep it up Jason.
Thank you!!
Lol, if you double tap the like button you simply cancel your like on the video
Double tap quickly on your phone and see what happens.
(X-Files theme song intensifies)
this video explained anti roll bars way better than your other video dedicated for them.
So basically they make a heavy and tall vehicle, put sports car performance in it and then deal with the problems with more technology. I guess that's how they do things today. Not for me, too expensive to buy and maintain. Nice video though!
It's a German thing. Over-engineering everything to death.
Either that or they can let it just roll over. I think this is a more elegant approach compared to carrying a jack to right the car after every turn. Plus, the more they make, the cheaper it will be, and then we might get this in even budget cars someday.
Right. And the system is liable to break down because of inferior components used in its manufacture.
Elon fixed the problem already. Golectric, batteries in the floor -
Yeah we should just go back to straight axles and leaf springs. Simple and Cheap.
Or better yet, Horses. My last horse lasted 30 years before it died on the side of the road.., and It refuelled itself automatically!
Good lesson for those thinking about fitting after-market roll bars just because "its supposed to be better". Balancing a car is not easy. Going at it "brute force" may change its behaviour, making it unpredictable. Just remember Senna's car in the first year at Williams, with terrible unpredictable mid-corner behaviour changes - and there were F1 engineers working on it! Not an easy task!
I put a stiffer sway bar on the back of my celica to counteract its understeer for this exact reason! Worked like a charm and its so much more fun to handle now
That was a nice presentation. However, I couldn't help but thinking, "is this expensive technology really necessary for a grocery getter?" I really don't think so. But the Audi Brand is all about pushing technology/engineering to its limits. Sometimes it works great but when it doesn't the customer is stuck with a gigantic bill😕
Well yeah, these are toys for top brands, which is why most of us plebs drive Civics...
Another thing to bear in mind is this is on the SQ7, which is the sporty version of the giant SUV. I can't find much info on it, but the base model Q7 starts at 50 grand, and I would bet that the electronic sway bar isn't standard equipment. On a car you can spec up past $100k, you can expect to find tech options that aren't necessarily practical or economically feasible, never mind that its durability is largely untested in the real world, but if you're spending that kind of money on a car you may be interested in the bleeding edge of technology, which this version of this system appears to be. It's probably not a box most people will check unless a) they want to do sporty driving in their 3 ton AWD children carrier or b) they want to get the price as high as possible for bragging rights ("Oh yeah? Well, I specced my Audi SQ7 up to 3x its sticker price, because I'm RICH!").
Well, current "pleb" cars are filled with features that once debuted on high end cars only.
That is an excellent point. I would hope that by the time this tech trickles down to the Nissan Z or Toyota 86 of the future that they've figured out either how to make it not break, how to fix it cheaply, or both. If the engineers can't make one of those two things happen, the people who decided which equipment goes in which models and trim levels wouldn't be doing their jobs if they allowed it into a car that would be totaled from a failed anti-roll system.
Yeah, it's pretty simple like that, the systems that can't be solved reliably and cheaply just don't end up going into the cheaper cars. Plenty of examples of such systems in the past as well. But you can't succeed if you don't try.
Thanks Audi but I'll stick with anti roll bars. 2 bushes and 2 or 4 links is all that can go wrong :)
Land Rover created the ACE system in 1998, doing the same thing here but with hydraulics rather than electrics.
It worked incredibly well, and in my 1999 Discovery 2 it is still working very very well.
And it still corners like a yacht.
Have you ever heard of the Bose Electromagnetic suspension system that came out in the early 2000s? If so, what do you think about it? They showed footage of it literally leaping over something they placed in the road. Pretty sweet!
Nice video!
This reminds me of the time, when Citroën took their trademark Hydropneumatic system in the late 1980s, added a microprocessor control system which resulted in the creation of the Hydractive system and it eliminated body roll altogether. And now there is their new system the "Citroën Advanced Comfort" in the new C4 Cactus - I didn't have the honor to try that one yet.
Csuzdi Gábor Hydractive is just about variation of stiffness in the suspension. The body roll is another system called Activa. Sadly these types of hydropneumatic suspensions have been remove from Citroën cars after the C5.
i see EE upload, i click like :D
Hello.
im from peru
Audi's anti-roll system is surprising, incredible.
Another (although not ideal or probably even possible) way to eliminate body roll is to adjust suspension geometry such that the roll axis (line connecting the front and rear roll centers) passes through the center of mass.
It's really neat that the computer technology/control has finally caught up with the physics of production cars... remember the Williams active suspension F1 car in 1993... banned instantly, of course. Thanks
Active roll bars make a huge difference. My BMW has a similar system, except the hydraulic couplers use pressurized power steering fluid. You can corner at ridiculous speeds and the car stays perfectly level.
Did you know the xantia Citroën? It's a real mind-blowing hydraulic system like this one! Keep the good work!
This is the same idea Citroen implemented in the activa (with hydraulic actuators) some 20+ years ago...
Citroen Xantia Activa had a similar solution in the mid 90’s.
It won every track test, needless to say!
I don't know.... it just looks like Audi has added something that will break eventually. So many things to break and go wrong on a car these days which is sad.
I always wonder why people say this. Do you not realize you just commented via a very advanced piece of technology? How often does that break. An engine is more complicated than this system, yet there are engines that run over 500K miles without problems.
Legitimate concern, especially from Audi. But even if it does happen, at leaat it's not a critical component.
Engineer's motto if it aint broke yet add more options.
Duskconqueror If you buy the best car you can justify based on your budget and the most random thing happens to it the average person has undue strain to pay for it if they have no factory or extended warranty. It's gotten to the point where if a car is financed for longer than the warranty lasts I can see banks requiring full coverage for maintenance or breakdowns. Just like with health care most people cannot handle the costs of even a relatively minor failure on modern cars especially if they are making payments too. So they may be more reliable for their complexity but tell that to a college age commuter when they suddenly and unexpectedly have to pay several thousand just to keep the car on the road. Many will just let the car go back to the bank.
Duskconqueror What a moronic comment,we have all seen those 'what if a car was a computer' comparisons. Have you looked at cars of the last 20 years? The jury is in. They break and are crazy expensive to fix. It is great technology for race cars. I will just deal with some body roll.
Love your videos, but for whatever reason, for me, the first description of how the system works (upper left of the whiteboard) seemed more confusing than your usual explanations. I'll rewatch it a couple of times and see if I missed something.
It will surely make cornering at the limit interesting, as the sway bar torsion adjusts so vastly, while still having a fixed or progressive spring rate.
BMW 7 Series calls this Active Roll Stabilization. Its just an Electronically controlled Sway Bar(s) located in the Front and Rear of the vehicle. It does make a big difference in countering centrifugal force/ Body lean.
Sounds like you can think of it as an extension to ESP, to not only adjust the wheel torque, but also the load transfer :) nice
Land Rover has been doing this for a while in a hydraulic application which in my opinion would be much more powerful than an electric system. My 06 Range Rover Sport Supercharged has the dynamic response hydraulic sway bars and corners extremely flat for its weight.
You should discuss the 1991 UZZ32 Toyota Soarer, that was actually innovative. Or even the Xantia Activa (have owned both of those cars).
All VAG have done here is look at systems that BMW and Land Rover have designed over a decade ago, and made it more powerful, must have been so hard for them to come up the idea...
I had a 1996 Citroen Xantia Activa with active roll control. Great car except if you stopped at lights with one wheel in a pothole ;)
Yeah, I'm experiencing the "Activa Shuffle" myself since yesterday XD
I would actually love to experience this. My ‘08 pilot (obviously) has a lot of body roll and a rather harsh ride since it’s so old. I have never really been in a car with very little body roll
Come to Europe and experience the world record holder: Citroën Xantia Activa. Zero point five degrees body roll. Beats any production supercar since 1999. Yes. It's French. I own one since yesterday and boy ... I'm not lying,
So glad to know that when I take this SQ5 to the track, I can adjust my sway bar on the fly.
This similar tech exist on my e60 550i bimmer called ASR or dynamic drive, both front and rear have a motorized swaybar.
I like body roll for fast road driving. I like feeling the weight shift and then leaning on the rear outside corner.
Handling balance understeer : oversteer is one issue. So presume a '70s or '80s front engine rear drive. If you make the rear stiff enough to get a nice neutral balance at mid corner, there will be a lot of weight transfer on the back axle, so as soon as you start to try to accelerate, (with your stock open centre dif) you get bad inside wheelspin. A much stiffer front swaybar is about 1/6th the price of a good limited slip centre. If you were tuning a car on the cheap, when I was young, you'd go very stiff on the front bar. That gave some understeer, but the bodyroll was much reduced and the power-down off the corner was dramatically improved. It did not in every way result in a car that was nicer to drive, (horrible understeer) but it sure as hell was quicker....
BMW had started doing this in the older 7 Series (I believe starting with E38 thru the F01 designations) cars using a hydraulic motor sway bar system.
Great explanation of a complex issue!
Body roll is the biggest problem in cars today, Citroën Xantia Activa V6 could beat sports cars thanks to its hydropneumatic suspension system.
Man, done decades ago, google Citroen Xantia Activa, zero body roll, so zero, it had to use special Michelin tyres, over side wall reinforce. No need for a shitload of electronics and yes it had a suspension computer and 6 piston high pressure LHM pump.
Ok, this system is different and obviously more advanced. but imho, more prone to problems.
Actually the system is developed and build by Schaeffler. Every electromechanical roll bar from other cars is build by them too. BMW for example uses a 12V version in the 7 Series, which has a similar design.
Magnific job, as always. Greetings from Barcelona!!
My BMW has the hydraulic version of this system (Dynamic Drive). I love it!
My 2008 550i. Look up videos of BMW ARS Test. It's incredibly powerful so much that it will fully compress the suspension.
I really appreciate the BMW logo in the left upper corner of the whiteboard - a subliminal message :)
Thank you for explaining the tech ins/outs in terms I can understand :). Anyone else and I'm like, "Wuh he say??". Another great video!
Hey, you should do a video on how power plants can operate at much higher efficiencies than car engines.
would love to get a video explaining how Audi achieved their Ultra addition of engines!
Interesting Video...: would you mind doing a Video talking about ALFA ROMEO Suspensions?
I am from Italia and in there ALFA always had the reputation of making the most stable Cars (they share some their Suspension Tech with Ferrari) and it's all thank's to what they call the "ALFA LINK" also known as the "Sospensione a Quadrilatero Deformabile" ... It is interesting that for a number of years rhey used this Tech even on front wheel Drive Cars and they were unbeateble in Stability Tests (yes: even BMW can't match it).
I have owned two ALFAs (a 159 and a 147) and i never drove any other Car as stable as those.
Now the newly introduced 'GIULIA' has an evolution of the Suspensions i had on my old ALFAs and i wouldn't mind understanding more of what their secret is in all that witchcraft of Torsion Bars and Beams that make their Cars drive like they are on Rails.
Thank you
Citroen eliminated body roll decades ago
Dimitri Andreou And Lexus did it too, with the LS400 Bose suspension
Thank you, came here to say this. Citroen actually did quite a few things that “innovative car makers” re-did decades later...
Yes they did, and the Xantia Activa V6 is still the car with the fastest speed ever at the moose test, and the video is almost shocking: It has absolutely no body roll, which makes it look like the car is going over that corner casually. The Bose system might have been even better (seriously, it's so impressive the demonstration video almost looks fake), but sadly never was in a production car.
Citroen did a demonstration model of the DS 60 years ago that did not have body roll
Hello Jason,
I really learned a lot about cars by watching your videos. Can you please make a video about "Should you park in gear when in an incline for manual transmission cars?" This was taught to me way back in driving school but I didn't really believe it because it doesn't make sense that it prevents your car from rolling down. It would be very helpful if you could explain it similar to should you press the handbrake button. I'm really curious if this is real or a myth.
Thank you.
Did anyone else see Car and Drivers article on this in last months magazine? They covered a few other manufacturers too.
Neat! I need to find a stand to check it out.
Hey Jason, I've got a question for you: while watching the last Formula E e-Prix, I noticed that the drivers, while reaching a corner, released the throttle pedal way before they hit the brake pedal, in order to harvest energy via the regenerative braking system. However, the graphic showed that the energy recovered in the period in which the driver was moving without touching any pedal was way lower than the energy recovered during the actual braking phase. Could you explain exactly how braking works on FE cars, or electic vehicles? Thank you, love your work!
This process sounds awesome if it is highly efficient but I wonder, how much would a system like this cost and how much to maintain or replace. It would be nice if they had setups you could add to other vehicles and programed.
Citroën Xantia Activa did basically the same thing almost 25 years ago.
Well I still think the best way to reduce body roll is getting a proper car with an acceptable weight and a CoG which is not up there in the clouds, but as far as lumbering 2+ ton wheeled tanks go, thi system is pretty nice.
The most interesting part of the video though was the explanation of the effect of wheel load differences on understeer.
I dont understund : with stiff front and more load on front out wheel i think that will increase friction on that wheeland give a good reactivity in turning
Land Rover's Dynamic Response (available in Range Rover and Range Rover Sport since 2013) works exactly the same way. The whole system was developed by Bilstein in the early 2000's, actually the previous generation of Range Rover already used something like this but not so advanced (it had only one channel, so both sway bars were actuated at the same time).
And so it still corners like a yacht.
This reminds me to put some bolts back into my rear and possibly front duel swaybar setup
I really should lock them some how because thread locker and nylock nuts don't work, maybe wired nuts..?
BMW had active stabilizers like 15 years ago, for example on E50 545i, not electric but hydraulic and it worked amazingly well. Now the problem that is obvious with Audi is the heat, how they are cooling the electric motor, obviously they are not, but if one drives like mad trying to go sideways non stop for like an hour this will overheat and give out.
Wasn't able to beat the Xantia Activa though. It's got the world record since 1999.
How do you adjust this in real time while turning a corner? where do you control it? steering wheel? foot peddle? head movement?
Awesome.....you know you should now try focusing on stuffs like fluid dynamics and material mechanics too, its a lot of maths and lot of fun.
To expand on this topic, you should do a video on the latest Range Rover Sport SV and it's 6D Dynamic Suspension. (Also ties into McLarens crosslinked damper system)
I want to see how this system does on the moose test compared to its predecessor, the standard sway bar.
Great video. This is probably great technology for race cars, but have you looked at cars of the last 20 years? The jury is in. These technologies break and are crazy expensive to fix. I will just deal with some body roll.
Can you make a video about fuel economy? How do different the factors affect it.
Instead of correcting body roll (keeping the vehicle level), can an active roll-bar system be used to cause the vehicle to roll into the corner, transferring more load to the inner wheels resulting in better traction and tighter cornering?
Citroen Xantia Activa was the best suspension system ive ever experienced in a road car.
There is a simpler method to prevent body roll that they could have implemented.
Many sports cars do it.
Looking at the car end on:
Imagine the wheels as just fixed on the ground.
Somewhere above the center point between the wheels is the "roll axis" of the car. This is what the car body rotates around as it leans left or right.
Picture someone pushing the center of mass to your left. Their ability to make the body roll depends on how far above the "roll axis" they are pushing.
If the roll axis and center of mass are at the same point, there is no roll.
The anti-sway system then only have to deal with the tendency of the body to rock side to side if you hit a bump with the wheel on one side.
I wouldn't be surprised if electronic ARB is how Lightning McQueen does his Kachow thing
Perfect timing
Thank you for another excellent video. Though I was generally familiar with front and rear anti-roll bars, your explanation regarding how the relative stiffness of the front or rear anti-roll bar can affect under/oversteer characteristics of the vehicle.
MB has been doing this for a real long time
And they couldn't beat a French car with it.
In think I'm getting addicted to these videos. I have 1 foot into building my own car.
One question if anyone can help: why would a stiff front wheel lead to understeer? Understeer means the front wheels slip, right? Wouldn't more vehicle weight on the front wheel lead to more friction? I don't see it yet...
A stiff front means the front has more work to do. Suspensions want to do as little as possible for optimum traction. The more pressure on a tire, the less grip overall it has. As you overwork the front tires, they lose grip and you understeer.
Wasn t BMW the first to introduce ARS in Bmw 7 series E65? In 2000 ?
What are the benifits of arb then
I'm going to tell what I understand and if there something wrong please correct it to me;
1.The change in camber decreases as there is no body roll
2. Related to the upove the contact patch will not increase a lot and this will be better for gaining higher cornering forces
Anyone else think the animation in this video is amazing?
The same effect can be achieved through the air supension. What is the difference between a mechanical rollbar and using the air suspension for it?
Citroen Xantia Activa, active anti-roll bars 1994. Don't tell me they didn't work either...
The notorious Teknikens Värld moose test results suggests otherwise.
Citroën Xantia 3.0i V6 Activa 1999 85 kph
Audi R8 V10 plus 5.2 FSI quattro 610 2017 83 kph
McLaren 675LT 2017 83 kph
Porsche 997 GT3 RS 2008 82 kph
People want to ignore your comment because it conflicts with their world view.
The problem with anti-roll bars is that lifting an inside wheel, especially if the car has a light rear end, on a bumper corner is very dangerous. Better to have no ARB and do active damping.
Audis are notorious for under-steering because of their engine and AWD setup. People complain for years. Audi responds with an over-engineered and complicated, electric solution. Well played.
Why not use electronic suspension to accomplish the function of an anti-roll bar? More specifically electronically controlled hydraulic shocks. This would take less space, would not need steel bars running along the axles thus saving weight, and could utilize the same 12V system. Many cars and even the new RZR has electronically controlled shocks... adding the hydraulics pressurization should be an ease.
An explanation of their new 48V system might be nice.
Won't roll, but it will still plow cuz the engine is in the front bumper.
I just love your videos.. very informative.. god bless.. but need to know that from where u get indepth knowledge??
Land Rover discovery 2 had a an active anti roll bar at front with a linear actuator at the link
Looks like Citroen Xantia Activa system. Only electric vs hydro pneumatic.
Really quite like this system! Doesn't seem as simple and durable as the system McLaren used in the mp4-12c (and Citroën C4 WRC). Does anybody know the pros and cons of these systems when compared to eachother?
Such an innovative technology great to see that audi can completely rip off what BMW did in 2007 whilst introducing a 48v electric system that isn’t compatible with anything and require its own battery and electronic systems that won’t stand up to the test of time. Soooooo innovative. 👌
My name Isalwaysjeff Audi isn’t the only manufacturer using 48V now.
My name Isalwaysjeff Great point 👍
Was thinking the same, active suspension on the E60, hydraulic antiroll linked to steering angle.. Over a decade ago
My name Isalwaysjeff haha. BMW rip off. Lexus presented this technology back in 1994 and uses till this day on selected models.
Nah, Toyota did in 1991, see the UZZ32 Soarer.
I wonder how this will affect longevity of components like bushings in the control arms, or ball joints. Is load subsequently transferred to them if an axle stiffens up?
My boss just got a 2011 Porsche Cayenne turbo. That thing corners FLAT. Flatter than my 1989 MR2 turbo. It also has enough brakes to pull your face off your skull. All while having a super comfortable ride.
I love German Engineering.
It won't beat my car in cornering flat. French car. 1998. Goes over speed bumps over 80 mph. That Porsche wouldn't stand a chance except in HP.
Jonathan/Justin/Jasper (I watched your April Fool's video and really enjoyed it), great video, once again! Quick question for you: if it's applying counter-torque, wouldn't it essentially be braking the outside wheel, causing the car to slow down to some degree? Maybe I'm just over/underthinking it but it just seems like the logical thing to happen in my head.
It's not applying a braking force to either wheel, as it's only connected to the control arms of the suspension. It can influence whether the control arm goes up or down, but it cannot impact the driving speed directly.
Engineering Explained Oh! Wonderful, that's what I was missing then. I do realize you mentioned it in the video, I think I just didn't understand it properly. Thanks for the explanation! Have a great day.
@Engineering Explained Most of the OEMs like Toyota and so on, have this kind of tech, normally they use a controller called "Skyhook"，some articles could be found on SAE。 What's more it works for ride and comfort as well.
How is this different from the active suspension in, say, a 2005 bmw 7 series? Does the BMW have an accelerometer?
August Sawzak works the same way. BMW has been using active anti roll bars in their larger cars equipped with sport packages since like 2007.
Akash Hegde yeah my dad has an '07 750i. It is a very heavy car but it corners very very flat.