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Electromagnetic Suspension System
chuckgrosvenor writes "Every automotive suspension has two goals: passenger comfort and vehicle control. Unfortunately, these goals are in conflict. Two much comfort, and the car rolls and pitches a lot, too much control and you feel every bump. BOSE has found the happy medium by using electromagnetic motors, power amplifiers, & computer control algorithms to even out the road, while still feeling connected to it. Check the quicktime movies to see two different cars stay level while they go through cornering exercises." Reader gatekeep writes "Amar Bose, founder of the Bose Corporation and MIT professor and alumnus, has recently unveiled a new electromagnetic car suspension system. It's said to have taken 24 years to develop. There's only minor technical details available so far, but the author of this piece describes seeing the system allow the test vehicle to jump over obstacles in its path!"
I recall hearing about this back in the very early 90's. they made it sound like they had a product and in about a year or two you would see them in the Big 3 cars.... still waiting.
I am the Alpha and the Omega-3
You want your tires on the ground at all times. When a tire leaves the ground, you lose control.
Pitching and yawing can be controlled with proper FBW controls as well as better center-weighted metering.
This is a gimmick. Not surprising, it is Bose... (Ever taken a look at the inside of their "omni-directional" speaker system? They just face the speaker inwards to create an echo chamber. It does nothing but muffle the actual audio.)
Erm... a system just as good as this, if not superior to it, has been around for quite a while, and in its current generation will do everything that this BOSE system does; most probably better. And this is based technology that has been around since the early 50s, with major changes only being introduced in the last 10 years or so.
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...The success of Bose is not due to superior products, but superior marketing. This article, this one, and this one all point to Bose offering low quality products with some heavy duty marketing to back them up. I'm really not impressed by this latest invention, it just sounds to me like the "Just add magical magnets" effect. Put on some magnets, call it magic, make some money.
Even those who arrange and design shrubberies are under considerable economic stress at this period in history.
Mercedes already offer a comperable system on the 2004 SL, CL, and S class. This has been availble in the CL since the 2000 model year. This page is pure Flash, but it describes the system. http://www.mbusa.com/media/richmedia/main/models/t ech_demos/abc/abc.swf
What kind of car are you driving? I haven't seen a system like that in a car for nearly a decade. They were in style for a few years in the late 80s and early 90s, but quickly died a quick death. I'm sure it had nothing to do with the fact that the automatic belt gave drivers a false sense of safety, thus causing them not to latch their lap belts. The lap belt is the most important piece of a three-point belt restraint system, and with only a shoulder belt you run a very high risk of slipping down your seat in a collision, catching the shoulder belt with your chin, and literally losing your head.
Assuming, then, that you're driving a 10+ year old car, it's no wonder you have these types of problems. Such computer-controlled systems were still relatively new, and they've come quite a long way.
"Between 1983 and 1987, the Lotus active suspension disappeared (from F1). According to Wright, "The system was being developed for road car use by Lotus Engineering." Many GGLC members may recall seeing videos of an active suspended Excel actually 'banking' into corners and running a slalom virtually flat." http://www.gglotus.org/ggtech/activesusp/activesus pn.htm
Question: are you talking about power steering that uses an electric motor instead of a fluid-based system?
Most of the new high-end BMW and Mercedes-Benz cars now use power steering systems powered by an electric motor due to the fact they weigh much less than traditional power steering systems.
Just pickin' 'cause i use my camera (a lot), but that is not really over-exposure, the technique used there is what is refered to as a "rear-synced" exposure....the flash is synced to bang at the end of the exposure lighting the subject at the end of its movement during the shot. You are most correct in stating that this is an excellent way to show how this suspension acts though...a damn good way. It's also how some very dramatic and motion-capturing shots are taken in nightclubs and other low-light situations. Very nice effect and used here perfectly.
;-)
Again, just picking 'cause i'm love with the camera
Wrong.
The Cadillac system is a high tech spring and damper system. The trick is that the viscosity of the (very expensive) damping fluid can be controlled by the application of a magnetic field. <Buzzword warning> Nanotech stuff, I believe </buzzword> The suspension can change it's damping rate, but the wheel is still being moved by the springs.
The Bose system is using what they call a linear motor (think solenoid, but not limited to on or off) to control the wheel. This suspension can lift the wheel or push it down. It knows the difference between a spring compression due to a bump and a spring compression due to heavy braking or cornering, so it knows whether to resist the lift of the wheel or to let it rise.
Cool stuff, if you ask me.
Never shake hands with a man you meet in a fertility clinic.
The mechanical springs are still in place and will support the chassis with power off. However, the ride is likely to be bouncy then.
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I believe you underestimate the cost of driving a mechanical fan. It's been a long time since I investigated, but I remember an estimate of tens of HP moving from a mechanical fan to an electric on some of the old ford V8 trucks. It sounds high when I think about it, but I'm guessing it's not cheap, especially in a context where my cars almost never run the fan (I wasn't entirely sure that I had a broken fan on one car until one sweltering day visiting DC, stuck in traffic (in front of the Supreme Court no less)).
And which "1% of autos that have that particular problem" are you talking about. The mechanical fan thing only works sans pulleys for RWD cars. All front wheel drive cars (nearly all passenger cars in the US) have transverse mounted engines where the engine cranks parallel to the wheels, perpendicular to the radiator. That alone was enough to drive the mechanical fan out of existence.
There's also magneto-rheologic fluid shocks, they do the same sort of thing but on a different principle. The fluid contains millions of tiny needle shaped particles in a oil suspension. In a magnetic field the particles line up make the fluid much more viscous. It works really well but the fluid is really expensive,maybe this way is cheaper?
I'm actually in the middle of swapping an electric fan from a Ford Taurus 3.8L into my 5.0L vehicle. Electric fans are cheaper energy wise, than mechanical clutch fans. At MOST my electric fan will draw 100A starting energy and about 30-40A constant. Even at 100A that's 1200W or about 1.6-1.7HP. Even with the conversion from mechanical energy to electrical energy at the alternator, assuming an abysmal 30% efficiency, that's still only a 4HP draw. My mechanical fan will draw well over 10HP. Maybe even 15HP at higher RPMs. Another problem is that if my fan clutch siezes, there goes my water pump. It'll take the bearings right out. So I'm removing a parasitic loss and a point of failure as well.
Slashdot is proof that Sturgeon's Law applies to mankind.
Hmm... I have a few problems with that assertion.
First of all, the gas used by spinning a small fan is nominal at best, and most likely that and much more gas is being wasted by other components that could be eliminated or just optimized.
Second, it wastes much more gas if you must first turn it into electricity, and then use it to do work. The losses right there quite probably make up the difference in gas... At least driving here in the desert where it's hot most of the time.
To quote from this article , you would be wrong:
The article also addresses a lot of your other complaints about changing the fan system from a mechanical one. But, what it really comes down to, is there were fundamental engineering problems that people were trying to solve. The electric fans in cars helped solve some of them. The article I linked discussed another type of fan system that tries to take it one step further.
I was thinking exactly the same thing.
Either
- they show both the movies for the original system and their system in slow motion, which would make their system even more impressing
- they should their movie in real time, and the movie with the original system in slow motion, which would be cheating
- they modified the original suspension, made it much softer, which would be cheating also.
I've been told that suspensions in general are stiffer here in Europe than in America, even that suspensions on cars imported from America are stiffened because Europeans like it better (some even say it's because they're not allowed on the road with their soft suspensions). Even if that's true, the suspension in those movies (if not in slow motion) seems softer than anything on the market.
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It sounds like a lot, but its not atypical. A power-steering module I worked with once drew about 90 amps peak. Our power distribution boxes regularly handle hundreds of amps of current.
Motors like to suck current. Its just one of those things. Auto world has been dealing with it for years now, and we've pretty much figured out how to handle high current loads (hell, we switch those 90 amp currents on and off in a box the size of a small hardcover book.)
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When this gets to be in normal cars, it's going to end the day of those god-awful "traffic calming" measures, where they embed humps in the road. Damn, but I hate that lurch-lurch sensation and the slowing and starting those things cause. Good riddance to them.
Basically, airbags started to make the news and Congress decided automakers were taking too long to implement them. So they passed a law stipulating x% of new cars sold had to have an automatic restraint system, with x increasing each year until it hit 100%. For a few years in the mid to late 80s, automakers that couldn't get airbags implemented/priced low enough used the automatic seatbelt thingamajig to satisfy the law. It was never "in style" - everyone hated them. That's why the lap belt wasn't attached. There's no way to automatically move the lap belt out of the way while the occupant is getting into the seat.