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New Car Can Lean Into Curves, Literally
cartechboy (2660665) writes "You know how motorcycle riders lean into the corners, sometimes even touching their knee to the ground? Mercedes-Benz has developed new technology that replicates that sensation by leaning the car into bends. It's called Dynamic Curve and it's part of the Active Body control suspension system on the new 2015 Mercedes-Benz S-Class Coupe. In turns, special plunger cylinders raise the suspension struts and lower the opposite side, depending on the direction of the bend. This has the result of tilting the car body slightly towards the inside of the corner, countering centrifugal cornering forces. Mercedes says it's not design for increasing cornering speeds, but increasing pleasure for the driver and passengers."
As long as internal car data bus allows me to tie the sound system to the suspension system so I can bounce with the music down the road.
Suspension on cars do this automatically, already. That's a big part of the reason we have suspensions on cars. I can't imagine there's that much of a benefit to counter the extra weight and complexity of the system.
I don't respond to AC's.
Rather have a LifeJet.
I'm still waiting for this to be mainstream
http://www.bose.com/controller...
Oblig
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
It will be used for rider's comfort. Not to take corners faster. I'm amazed they don't pretend it's for safety, like all the other gadgets and improvements that, eventually, led drivers to drive faster and more risky because their gadgets allow even the worst driver to keep his car under control at higher speed.
Which doesn't mean that I think anti-lock or traction control are bad things. Quite the opposite. But someone should tell the idiots that they were NOT meant to be used as a substitute for knowing how to drive, dammit!
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
This adaptive suspension technology can be valuable for addressing poor roadway design, such as opposite-camber banking (yes, such things exist and can be very dangerous in poor weather). One of the most egregious examples of opposite-camber banking occurs in Canada between Vancouver and Burnaby, BC on Boundary Drive on which vehicles travel steeply downhill, typically in rain, and are presented with an opposite-camber dogleg turn about half the way down. So, while everyone is riding their brakes their vehicle suddenly gets crossed up. Since it is noticeably uncomfortable in a low-slung sports car, it is more than an annoyance on buses and in large trucks. Redesigning/repairing those poor roadways can take years, so any step by vehicle makers to have this kind of adaptable suspension is worthwile.
I deny that I have not avoided attaining the opposite of that which I do not want.
American cars have been leaning over while turning for decades!
Drivers depend on feedback from the car to help them make necessary adjustments.
If a curve isn't banked enough, the car shouldn't fool the driver into thinking that it is banked enough.
That feeling one gets when the car leans towards the outside of the curve is telling the driver to slow down!
The car is designed to ride ~5 inches above the road surface. A normal car like this might tilt 2 degrees in a curve, toward the outside of the curve, causing that part of the car to be ~4 inches from the road surface. This Mercedes could conceivably tilt 2 degrees toward the inside of the curve, causing that part of the car to be about 4 inches from the road.
The total difference between the tilt of a normal car and this Mercedes is perhaps 2 inches. Not at all like a motorcycle tilt in the same curve, in fact probably not detectable by the driver except for the cost of the extra complexity.
...omphaloskepsis often...
"Mercedes says it's not design for increasing cornering speeds, but increasing pleasure for the driver and passengers."
Of course if it not literally going to make the car faster, but if you reduce the drag on the driver, the end result will be faster turns.
Troll is not a replacement for I disagree.
http://en.wikipedia.org/wiki/Citro%C3%ABn_Xantia
They did it in 1999 with their typical suspension to eliminate any body roll.
In fact, first they made it lean into the corner, but test showed customers didn't like this behavior.
Still holds the highest speed in the elk/moose test: 85 km/h vs 80 km/h for the second one: Porsche 911!
Suspension on cars do this automatically, already.
No they do not. Traditional suspensions do exactly the opposite of what this system does. Traditional suspensions compress the springs on the outside of the turn rather than the inside. This is why you are pushed into the door instead of into the bottom of your seat.
Source: I'm in a motorcyle gang and often race (legally and otherwise).
But evidently not competitively on a track. The practice is not uncommon.
But i really prefer the sound of screeching tires.
IIRC Volvo and Mercedes, and maybe some other car makers were working with active suspension systems that had this feature about 10 years ago. But IDK if it ever made it to a production model.
It's easier to be a result of the past, but more fun to be a cause of the future! http://www.spacefinancegroup.com/
Mmm... lower perception of centripetal force may encourage drivers to go faster into corners. I remember reading comments supposedly from highway safety researchers that insulating drivers from road noise and vibrations, as modern cars do, reduces their perception of speed, thereby increasing the likelihood and severity of road accidents. Let's see what happens to accident rates on corners with cars fitted with this device.
Quick, tell Valentino Rossi the news! I'll bet he'll be happy to know that he'll never have to wear knee sliders again.
My Subaru Impreza already does this.
That comic proves the opposite point. Its not a myth, its a viewpoint. Fictitious force true, but within the correct frame of reference, it is a real force force. Which is exactly what that comic says.
Please, just stop saying Centrifugal Force is a myth and does not exist. Its a frame of reference measurement and very real to anything inside that frame.
Learn how to drive, not how to crash.
Is this coming to US markets at launch? I know their 4matic AWD system is, which does improve handling – and possibly before other markets.
A couple of others have mentioned the ~2007 work that Bose did in active suspension, but nothing really clarifies the idea like pictures or video:
http://www.youtube.com/watch?v=eSi6J-QK1lw
Leaning into a curve is one thing, but At 1:40 the car jumps a curb-size obstable. Nice.
I'm not sure it's worth the engineering complexity versus standard sway bars (for a typical diver),
http://www.youtube.com/watch?v=_liGnV3PTiQ
but Bose's system (and Mercedes') sure as hell is cool.
And while we're on the topic of making unreasonably large cars more agile than they ought to be, I'm still pretty happy with Volvo's 4C system and oversized sway bars on a 7yo S80 V8 -- switching to "advanced" it behaves like a fat WRX or that pudgy football player you didn't think could move that fast, and in "comfort" mode it hunches down *evenly* about 6-8cm in hard curves... all with just plain old leverage, a few poly bushings, and electromagnets around the ferro-oil filled shocks. Simple is good.
I think not...(*poof*)
Bah! THe french beat the Krauts by 20 years. Choeck out the 1994 Citroën Xantia Activa. Here's a video demonstrating the active suspension, plenty more race footage on Youtube http://youtu.be/kQT7IMHvBGo
And I was under impression that toyota's KDSS did this too...
"If anything can go wrong, it will." - Murphy
posting to undo accidental moderation
Just because it's a technically a "force" doesn't mean it doesn't exist.
Actually, you can get the car to roll to the inside of a corner without active suspension. Just design the suspension so the the roll axis is above the center of mass for the car. You can also design the suspension so that the car does not dive down in front on braking or squat on acceleration. This was tried with the Lotus F1 cars in the seventies and abandoned because the drivers disliked it. The diving and squating was providing them with valuable feedback on how much braking/accelerating they were doing. Lotus also had an experimental road car with active suspension that "leaned to the inside" that was never produced. I wonder if the Mercedes active suspension is going to hide from the driver just how fast they are taking the corner.
Active roll control was done in the early 90's by Citroen. Chaec out 'Citroen Xantia Activa'. It had the capability to 'lean inwards' (just a parameter in the software) but they stopped short, just controlling roll and keeping the car level as not to 'alienate' normal drivers.
Definitely something I would want in my car, but for the below average driver the outward lean helps 'feel' where the limits are.
Knee dragging serves a purpose. What do you "race" legally? Motocross?
Have you *never* leaned so far that you scraped the frame? If not, then you are a bad "racer" and may have ridden a lot, but have never pushed the bike or yourself.
"motorcycle gang", what, you and two of your accountant buddies go ride bikes Wild Hog style once a year?
Learn to love Alaska
It is a gimmick, and a welcome one. Makes the car feel like it turns like a plane or bike: by banking. Completely artificial but I'm tellin' ya, if I feel it I'll probably buy it.
I don't like how cars and boats go about bends. I live with it, I choose my cars to make short work of the bends and have fun doing so, but I'd much rather feel a turn like in a plane or bike.
Benz has been toying with this for at least 15 years, Some tv show had it, they also had a benz bike with four wheels which kinda scissored leaning you into the turn. But they also had a small four-wheel car doing it. Both got my attention... but now here's the car for-reals.
The "Civilized World" jumped the shark ca. 1973.
Mercedes says it's not design for increasing cornering speeds, but increasing pleasure for the driver and passengers.
Personally, for greater pleasure, I would prefer hookers giving blow jobs.
Actually, the force that is pushing you against the seat is centripetal force, not centrifugal force.
Depends on your reference frame.
The only real force is the angular one
Centrifugal force is quite real. So is the Coriolis force and the Euler force . All three occur when the reference frame used to describe the force accelerates relative to another reference frame and in fact you cannot accurately solve many classical mechanics problems without them. For example the surface of the Earth is a rotating reference frame. Don't confuse the meaning of the term "fictitious force" to mean that it doesn't exist. A fictitious force is one that simple doesn't exist in an inertial reference frame. There still are non-inertial reference frames.
"You know how motorcycle riders lean into the corners, sometimes even touching their knee to the ground? Mercedes-Benz has developed new technology that replicates that sensation by leaning the car into bends.
How am I suppose to get my knee on the ground from inside the car? Geesh.
It must have been something you assimilated. . . .
ABS is dangerous to people who learned to drive without it.
Only if they are not competent drivers to begin with. ABS was not on the vast majority of cars when I learned to drive and we seem to have somehow survived the transition. ABS demonstrably makes drivers safer and there is plenty of data to prove it.
The normal technique of locking and releasing the brakes by pumping the pedal doesn't work, because the brakes never lock in the first place, so all you end up doing is repeatedly letting go of the brake for no reason.
Manual pump braking works exactly the same way with or without ABS. ABS does exactly the same thing as manual pump braking but ABS does the braking and releasing but much faster than any human could possible do it and therefore it works better.
The only time I have ever slid though a stop sign in the snow was in an ABS vehicle.
Oh, well, one anecdote should convince us all... [/sarcasm] You can still slide in an ABS equipped vehicle if the road is sufficiently slippery. If the surface is truly close to frictionless it doesn't matter what kind of brake system you use. You are along for the ride. For example my driveway is fairly steep and after an ice storm you are going to slide down a portion of it. It does not matter what you do with the brakes because there is basically no friction between you and the road. You didn't slide through the intersection because of ABS. You slid because you were going too fast.
Mercedes says it's not design for increasing cornering speeds, but increasing pleasure for the driver and passengers.
...but is drivers discover that the new Mercedes has superior cornering ability that will be purely coincidental... honest...
increasing pleasure for the driver and passengers.
Anyone else feel slightly dirty after reading that?
systemd is Roko's Basilisk.
Um, People who don't know squat about setting up a car suspension are chiming in all over the place. Guess what a good sports car suspension and even a lot of more mediocre cars already cause the wheels to lean like a skier going throught a bend. Take any newer german car and turn the wheels all the way in one direction and you'll be able to see that tires lean into the turn. If the car has stiff sway bars and a low CG,* they will cause the car body to roll into the bend due to the camber of the wheels. All of this is achieved without any sort of electronics just plan old fiddle with the suspension geometries.
*if CG is low enough you won't need sway bars to get the body to roll into the turn.
Formula 1 outlawed it in 1993.
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
Didn't Citroen have this feature decades ago?
Oliver's law of assumed responsibility: If you're seen fixing it, you will be blamed for breaking it.
I think whatever focus group recommended this to Mercedes has trolled them very successfully. I'd think that this 'feature' would freak out people riding in the car and not be pleasurable.
Are YOU using the TOOL, or is the TOOL using YOU? Think about it!
I've been working with this car recently. It's pretty magical to see the automated steering work for the first time (wheel move by itself). It only works for 10 degrees turning and after 6-10 seconds the car hounds you to take control. While technologically marvelous, in practice it's just a safety feature to prevent people from drifting off the road if otherwise distracted, and it works VERY well! In combination with the distronic cruise system it definitely has life-saving capacity.
What a novel idea! Better rush out for a patent before someone finds prior art...
http://www.popsci.com/blog-network/speed-lab/toyota-i-road-test-drive-three-wheeled-electric-vehicle-answer-urban-gridlock
http://www.youtube.com/watch?v=kfmg53kPJMg
Can they make them dynamically vibrate too?
Roll down the window? Install a doggy door?
Very dangerously, the key is not to fall out of the car while still maintaining control.
BlameBillCosby.com
https://www.google.com/patents... Might be slightly new in a production vehicle.
Can't wait until I'm 150% outside the cornering envelope when the system decides now is a good time to reboot.
First generation RX-7 did this passively at low to moderate G-loads but not at high G loads where it is more critical to bias toward oversteer. It's about time manufacturers are designing vehicles to do this actively.
The Christian Right is Neither (Christian nor right). See: Matthew 23, Matthew 25, Ezekiel 16:48-50
In the 1960's the 600 limo had that as a feature on its air suspension (http://en.wikipedia.org/wiki/Mercedes-Benz_600) it really impressed a reviewer at the time. It had a ride like a boat.
...erm, buy a bike? (but then I suppose mercedes drivers wouldn't have the kahunas)
All Formula 1 cars had active suspensions in the early 90's. They were computer managed to keep the car flat in the curves and maximize aerodynamically generated downforce and also to absorb impact with kerbs in chicanes with almost no rebounds (more traction). Actually they were introduced by Lotus in the early '80s but didn't get mainstream because of weight and limitations in the electronics. Williams had a better version of them in their 1991 car (electronics got much better by then) and eventually all the team followed suit until FIA banned the technology starting from 1994 because of safety concerns (Zanardi barely survived a heavy crash due to an active suspensions failure). More details on F1 active suspensions here.
Production cars used them since the 80's.
What Mercedes is doing now is reminiscent of the early Italian high speed train Pendolino. "By tilting, the train could go around curves designed for slower trains at higher speeds without causing undue discomfort to passengers." See one of those trains tilting in a curve in the UK in 2012.
That would depend on how often you used both ...
You may think me a tired, old, cynic. I'd have to disagree about the tired bit.
This is not news Really, a Dutch company have done it in the past called "Carver"
there "car" called "carver 1" has that ability - it was a car for 2 people.
http://youtu.be/TK4wzBYmTIo
Sway bars help limit the *lean out* of the curve but never actively counter it. That happens at the cost of a lot of comfort while driving straight and less grip on bumpy surfaces. There's a reason cars have live axles these days and sway bars that are too thick will effectively turn your axles back to solid.
I was promised a flying car. Where is my flying car?
Force requires energy and the only energy being put into the system is rotational, and everything else that appears to be a force is simply some aspect of momentum
Congratulations, you just described movement in a non-inertial reference frame but you flunk vectors 101. Force requires mass and acceleration and nothing else - energy is merely a derived result in this case. The acceleration can be straight line or rotational. Acceleration occurs any time you have a change in velocity which is a vector. Change the magnitude (speed) or the direction (heading) and you have accelerated. So-called "fictitious forces" occur in the later case due to Newton's second law. The effects are real - they are only fictitious in the same sense that imaginary numbers are different from "real" numbers. You need both "real" and "fictitious" forces to accurately describe certain phenomena and the force (or force-like depending on reference frame) effects are demonstrably very real. In curved spacetime, ALL reference frames are non-inertial and in the real world spacetime is curved as far as we can tell. So saying "fictitious forces don't exist" is equivalent to saying we live in flat spacetime. This does not match our observations.
And while we're on the topic of making unreasonably large cars more agile than they ought to be, I'm still pretty happy with Volvo's 4C system and oversized sway bars on a 7yo S80 V8 -- switching to "advanced" it behaves like a fat WRX or that pudgy football player you didn't think could move that fast [...] all with just plain old leverage, a few poly bushings, and electromagnets around the ferro-oil filled shocks. Simple is good.
The A8Q managed that in 1997 without fancy shocks :)
You definitely feel the fat when you're going around a lumpy turn, though. There's no way around that. If you want to corner hard in the real world, you're still better off with a WRX.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Xantia, C5 and C6 models based on hydraulics since the nineties https://www.youtube.com/watch?...
.. 30+ years ago?
http://www.maxmatic.com/ttw_le...
(Saw it at EPCOT very many years ago...)
Lotus developed a system like this in the 80's. Some production cars even made it to the street.
Maybe they didn't "lean in" .. but they could have. I remember reading a talk from an engineer from Nissan/Infiniti who said they did try the "lean in" back in the 90's, but it was too weird for most drivers.
I've seen photos of Mercedes prototypes doing this as much as 10 years ago, so it's not a new idea. It didn't come to market, so I guess that there were some issues with mass-market implementation. I owned a Mercedes E350 that had adaptive seats: the bolster on the appropriate side squeezed you during a corner. It's a weird sensation, but you get used to it quickly, and it's pretty neat. Banking the whole car into a bend, as in an aircraft, would feel exactly as it does in an aircraft: you lose the lateral force, and it's replaced with a small, largely imperceptible, increase in vertical force, i.e. you weigh a little more.
Back in my VC days, when we were looking at "green" companies, a company came in with a pseudo-car (a little one-in-front-of-the-other two seater, more like an enclosed motorcycle, or, more precisely, a trike). Its claim to fame was that it leaned in corners. Man, if ever there was a demo that helped guide a decision to not invest, this was it. I ride motorcycles, so am used to leaning in corners. But sitting in the back of this thing for 5 minutes convinced me that nobody would put up with it. The Mercedes experience is likely to be better....
To be picky and literal, touching a knee slider to the ground is different from touching a knee to the ground.
I had a Mercedes with a precursor to this system, called Active Body Control (ABC) and it was anything but reliable. While it worked the car was fantastic - it would self-level, absorbs road imperfections, you can adjust height, and it lowers itself at a highway speeds to improve aerodynamics. When it doesn't work you can't drive the car at all since the car drops down as if it has no suspension and has to be towed tot he shop. To make things worse - towing ABC-equipped car also becomes highly problematic since you can only put it on flatbed, has to be careful strapping it down, and have to use special rolling jacks to load and unload it.
Any hydraulic suspension is a very complex system - it has a hydraulic pump to maintain pressure, it has gas 'sphere' accumulators to serve as dampers, and special hydraulic struts, plus distributors/valves and lines. On top of this system are miles of wiring, tons of sensors and electronics.
ABC struts leak, spheres burst, pump gets worn out and quits, sensors malfunction, valves get stuck. To make things worse - hydraulic fluid change is not part of regular maintenance for these cars, as such this system is known to fail due to contamination.
Owning any Mercedes with hydraulic suspension that is out of warranty is insane, it does not fail gracefully, parts are available only from Mercedes, and diagnostic tools are only accessible by Mercedes-authorized shops. Talking with other owners of similar cars - average lifespan of such system is about 8 years.
Some twenty years ago, I saw a TV spot starring Carl Lewis. He said that he liked some new european car (maybe a Citroën?) because it was the only one that dealt with the curves without tilting - very much the way he did when running.-Ignacio Agulló
Back in the early-mid '90s there was an active-suspension version of the Infiniti Q45. The engineers at the time said they could make the car lean into turns, but they didn't because test audiences found it too disconcerting.
Downmodding is the refuge of the weak. Don't downmod, make a better argument!
A company called Wesll developed leaning suspension on a prototype quad. It uses motorcycle wheels & tires so it can maintain surface contact on the curved tires while leaning. http://wesllcorp.com/
Mercedes has had some version of active body control since the 1970s. It became computer controlled in the 90s, and then in the early 2000's it became what it is today. This new announced version is merely a software upgrade on the tech that has been in production since the introduction of the 5th generation SL.
I'm quite disappointed with the ride quality of most hookers.
I don't know about Mercedes, but the hydraulic suspension systems on citroen vehicles actually was very reliable and problem free if and only if it would get the right kind of maintenance, like changing hydraulic fluid every 60.000km and cleaning the filters and checking the pressure on the pressure spheres. Although easy to fix, most garages would not know about this or charge rediculous prices for it, lease companies don't care, so the cars have a bad reputation and can be bought cheap with totally clogged hydraulics and no suspension at all.
I think key mistake with Mercedes was not including hydraulic system flush and filter change into regular maintenance. I blame marketing wanting "hassle-free" soundbite.