Follow Slashdot blog updates by subscribing to our blog RSS feed

 



Forgot your password?
typodupeerror
Transportation Technology

Electromagnetic Automobile Suspension Demonstrated 274

Posted by timothy
from the now-about-that-steel-plate-in-your-head dept.
cylonlover writes "Last December at the Future of Electric Vehicles conference in San Jose, a representative from The Netherlands' Eindhoven University of Technology presented research that his institution had been doing into a novel type of electromagnetic vehicle suspension. Now that a test car equipped with the suspension is about to appear at the AutoRAI exhibition in Amsterdam, the university has released some more details about the technology. For starters, it is not only electromagnetic but also active, meaning that it doesn't just mechanically respond to bumps in the road, but is controlled by an onboard computer. It is claimed to improve the overall ride quality of cars by 60 percent." That seems an awfully exact figure — I'm not sure any two people would ever agree even about the exact same car's "overall ride quality."
This discussion has been archived. No new comments can be posted.

Electromagnetic Automobile Suspension Demonstrated

Comments Filter:
  • Don't we already have technology like this in many supercars or GTs? Ferrari 599 comes to mind.

    • Re:Supercars (Score:4, Informative)

      by Tx (96709) on Wednesday April 06, 2011 @05:54AM (#35731072) Journal

      Even cars such as my VW Scirocco GT have similar systems (VW calls it Adaptive Chassis Control [volkswagen.co.uk]), it's not the preserve of supercars anymore. However according to the article, existing systems use hydraulic actuators, this system is apparently electromagnetic only, reacts faster and uses less power. Yes, I know, it's almost cheating to RTFA.

    • Re:Supercars (Score:5, Informative)

      by subreality (157447) on Wednesday April 06, 2011 @07:05AM (#35731428)

      Negative. This is not that system. There are a number of cars that let you adjust the shock absorbers on the fly: at the entry level, this involves servos adjusting the shock valving; at the high end (such as the F599) they use electromagnets to adjust the viscosity of the fluid in the shocks, which can be done much faster.

      This system is altogether different: there is no shock absorber. They have a linear motor in its place. This gives advanced capabilities that adjustable shocks cannot.

      For instance, say you turn hard left. The car wants to lean right. Soft springs are good for comfort, but allow the car to tilt more. This system lets you use soft springs, and then actively counter the body roll by pushing on one side and pulling on the other. The net result is you have the best of both worlds: the smooth ride of a luxury car's soft springs combined with the fast response and stiff anti-roll characteristics of a sports car.

      You need a very strong linear actuator to make a meaningful improvement, but those are expensive and require a hefty electrical system to power them, further increasing the price. Bose did some fantastic demos of these some years back, but I don't think they managed to get any manufacturers interested, probably due to cost. Hopefully these guys have improved in that regard.

      • by Gordonjcp (186804)

        The Citroen Xantia Activa used a pair of hydraulic rams to counteract roll forces, as well as the four hydraulic rams that comprise the normal suspension. Apparently they maintain grip to 0.98G lateral force - they certainly can be flung round tight corners much faster than anything with those obsolete old sofa springs at the corners.

      • by afidel (530433)
        My concern would be with failure mode, if the electronics in a variable viscosity system give out you still have a hydraulic shock, when this thing goes you instantly have a failed suspension system which would be "not good" if you were in the middle of a high speed turn.
        • by drinkypoo (153816)

          I really like how nobody bothered to RTFA, which is not unusual, but which addresses this point. If the power goes out it still damps, it just doesn't have variable damping.

          I understand not reading the fine article before making a comment about something related, but actually bitching about something that ain't even true and which is covered in the article is kneejerk slashbotism.

    • by Bengie (1121981)

      I saw an electromagnetic suspension demo'd on the Discovery Channel before many many years ago. It was computer controlled and polled the system thousands of timers per second to look for crests or troughs.

      How it faired over a pothole was quite cool as the car stayed level and barely moved, but what really got me in the demo was how it handled a curb. The driver went about 25mph strait into a curb and as the wheels hit the curb, the shocks sensed it and literally pulled the wheels up into the wheel wells an

      • by chudnall (514856)

        I would pay an extra 5k to be able to basically ignore the speedbumps they put up incessantly around here.

      • by h4rr4r (612664)

        Sounds like driving it would suck. Could never feel the road.

      • by TheLink (130905)
        I wonder how that car deals with slopes.

        I suspect it's going to be bad if it thinks something is a bump when it's actually the beginning of a steep slope.

        There's a limit to how high you can pull up the tires. Once you've got it maxed, and there's still some more "bump" there'd be no more room for shock absorbing...

        So I guess a really practical version would either have to have you still feel the bigger bumps when you're going high speed, or have additional sensors to tell the difference between bumps and sl
  • The first thought that came to my mind when reading this post were hovercraft over water and maglev trains.... No give me a power source that has nothing to do with fossil fuels and you might have a winner!
    • I can't believe the number of people that think the only by-product of fossil fuel is gasoline. Even the roads you would drive your no-fossil-fuel vehicle on are made out of by-products of fossil fuel. The resin-molded arm-rests. The insulation around every wire, the rear-view mirror enclosure. The window tint. The lubricating oil. The foam in the seat. A vehicle that has "nothing to do with fossil fuels" would not be a winner.
      • by MightyYar (622222)

        I can't believe the number of people that think the only by-product of fossil fuel is gasoline.

        I hate to be a pedant, but you started it :) It's only a fuel if you burn it. Someone can quite rightly say they want a no-fossil fuel vehicle and still use plastic. Cars in particular are very recyclable.

    • by Ksevio (865461)
      Whenever I see stories about new suspensions, I think of the skateboard in Snow Crash. It made the ride smooth by looking ahead to predict how the suspension should be rather than a reactive solution. That would make the smoothest ride though would be difficult to implement.
  • Bose (Score:4, Informative)

    by lcampagn (842601) on Wednesday April 06, 2011 @05:34AM (#35730978)
    I'm pretty sure Bose did this at least 4 years ago: http://www.bose.com/controller?url=/automotive/bose_suspension/index.jsp [bose.com]
  • by DataDiddler (1994180) on Wednesday April 06, 2011 @05:36AM (#35730986)

    That seems an awfully exact figure — I'm not sure any two people would ever agree even about the exact same car's "overall ride quality."

    Dutch people have the rough analogue to "perfect pitch" for ride quality. I'm guessing they got to about three significant figures in the study but rounded it off to sound a bit more plausible to the rest of the world. No serious studies have to be done on why exactly Dutch people have this ability, but the current predominant theory among many is that it has something to do with putting mayonnaise on french fries.

    • What? Who wouldn't put mayonnaise on french fries?

      (assuming they ate french fries, which I no longer do)

    • by raddan (519638) *
      I don't have a problem with averaging over people's reporting of "average ride quality" to come up with a figure like "60% better". Subjective measures are important, particularly if you're an automobile manufacturer. Nobody cares that it is hard to pin down what a 5-star rating on Netflix means, but it is clear that a movie rated 4.5 stars is seen to be better than a movie with 1.2 stars.

      What I'm more concerned about is: how did they conduct the study? Did the same people ride in both cars? Could te
    • by turing_m (1030530)
      Thanks, this thread needed more levity.
    • by TheCarp (96830)

      I will note though.... 60% isn't terribly exact. 60. is far more exact, as is 60.0

      They only reported 1 significant figure!

  • a representative from The Netherlands' Eindhoven University of Technology presented research that his institution had been doing into a novel type of electromagnetic vehicle suspension.

    Flying cars :)

  • but if I had a hybrid/electric car I'm pretty sure I would rather that electricity go to turning the wheels, not keeping my chassis away from them.

    • That's what the spring is for. An electromagnetic "shock absorber" dampens oscillations by collecting the energy as electricity. It is essentially a linear motor run as a generator.

    • by pthisis (27352) on Wednesday April 06, 2011 @06:49AM (#35731334) Homepage Journal

      but if I had a hybrid/electric car I'm pretty sure I would rather that electricity go to turning the wheels, not keeping my chassis away from them.

      According to TFA, the system actually draws less power than hydraulic shock systems:
      With a peak consumption of 500 watts, the suspension uses about a quarter of the power of hydraulic systems. It also stretches its battery life by using road vibrations to generate electricity. The designers believe that with refinements, the suspension's energy-efficiency could be improved even further.

      • by Gordonjcp (186804)

        They are probably talking about pressurised hydraulic systems. You'd be surprised how much the coffee mug sized hydraulic pump on a hydropneumatic Citroen takes to run - possibly as much as 2hp with a heavy demand on the hydraulics. That said, most of the demand is from the power steering; the brakes use about a tablespoon of fluid every time you press the pedal and once the car is up to normal ride height it only takes a little trickle of fluid to keep it there (usually it'll take two hours for it to set

        • by drerwk (695572)
          I am not sure about the brakes using only a tablespoon. If I recall on my ID-19 and DS, there is an anti-dive mechanism used during braking and I think it worked by putting more fluid into the front suspension, which not directly due to braking would still cycle the pump.
    • by necro81 (917438)
      While electrically active suspensions use power, the best-designed ones can be regenerative: when the wheel gets pushed upwards by a bump in the road, electrical power can be extracted from that stroke. Another consideration is the overall efficiency of the vehicle: keeping the wheels in better contact with the ground and the car at a constant elevation over the road leads to increased overall efficiency. In any car, vibration through the wheels and noise is wasted power. Even considering the power invol
  • I have a 2002 Cadillac STS with magnetic ride control. Here is a 2002 press release.

    GM's Magnetic Ride Control - The World's Fastest Reacting Suspension

    Detroit, Mich. - General Motors took vehicle handling and comfort to a new level with the January introduction of Magnetic Ride Control on the 2002 Cadillac Seville STS, the world's first production car with this leading-edge active suspension.

    GM's Magnetic Ride Control is a complete, stand-alone vehicle suspension control system that uses innovative magneto-rheological fluid-based actuators, four wheel-to-body displacement sensors, and an onboard computer to provide real-time, continuous control of vehicle suspension damping.

    The system responds in one millisecond to provide superior ride, handling and control on even the roughest road surfaces. Magnetic Ride Control uses a simple combination of sensors, as well as steering wheel and braking inputs from the driver, to reduce noise, vibration and harshness for a smoother ride.

    The system's onboard computer reacts to wheel inputs from the road-sensing suspension by sending an electronic signal to coils in each damper, changing the damping fluid's flow properties. This fluid contains randomly dispersed iron particles that, in the presence of a magnetic field, align themselves into structures adopting a near-plastic state. This action regulates the damping properties of the monotube struts, changing up to 1,000 times per second.

    The system offers an expanded range of soft-to-firm damping capabilities for increased control over vehicle motions for a flat ride and precise handling. The active suspension helps maintain the maximum amount of tire patch in contact with the road, providing improved wheel control for a safer more secure ride. This new technology also helps reduce the traditional tradeoff between ride and handling.

    Magnetic Ride Control is superior to the traditional suspensions and the real-time-damping systems found in other performance and luxury vehicles that use an electromechanical valve to control hydraulic pressure for shock damping.

    Engineers at GM Research & Development laboratories, and later with experts at Delphi Automotive Systems, explored ways to reduce or even eliminate the inherent restrictions of valve-based damping systems. The result is GM's revolutionary system that eliminates electro-mechanical valves entirely.

    Magnetic Selective Ride Control will debut as standard equipment in the 50th anniversary Chevrolet Corvette for the 2003 model year. That system will feature tour and sport suspension settings. The tour mode, with its extended range of damping capability, is so capable that it alone provides all the control an everyday driver needs. The sport mode, provides an extra measure of control and feel for performance enthusiasts who want to take their cars on track.

    This technology yields greater levels of tuning precision and ride quality. Ride and handling engineers developing vehicles with Magnetic Ride Control can spend their time adjusting the algorithms that control the damping responses on a computer, and are enabled to fine-tune ride and handling characteristics to unprecedented levels of specificity. As a result, drivers will notice better ride quality, less body roll and improvements in overall handling.

    General Motors , the world's largest vehicle manufacturer, designs, builds and markets cars and trucks worldwide. In 2001, GM earned $1.5 billion on sales of $177.3 billion, excluding special items. It employs about 362,000 people globally.

    ###

    Magnetic Ride Control: Fact Sheet

    What is Magnetic Ride Control?

    Magnetic Ride Control is a complete, stand-alone vehicle suspension control system that uses magneto-rheological fluid-based actuators, four wheel-to-body displacement sensors, and an on-board computer to provide real-time, continuous control of vehicle suspension damping.

    How does it work?

    Magnetic Ride Control is made possible by the development of magneto-rheological (MR) fluid located inside the monotube shock dampers. The fluid is a suspension of magnetically soft, tiny iron particles in a synthetic hydrocarbon-based solution. The fluid's consistency can be manipulated through the precise application of electronic current, resulting in continuously variable, real-time damping. In fact, the development of MR fluid is so significant that medical researchers have adapted it for use in high-tech prosthetic devices, such artificial knees.

    What are its benefits?

    The system provides a greatly expanded range of soft to firm damping capability, a truly continuous range of damping settings providing increased control over vehicle motions for a flat ride and more precise handing. The enhanced road-holding capabilities improve wheel control for a safer, more secure ride.

    Magnetic Ride Control offers greater roll control and handling during transient maneuvers, and helps reduce noise, vibration and harshness for a smoother ride. This new technology helps reduce the traditional tradeoff between ride and handling, and responds 5 times faster than previous real-time damping systems. In addition, greater reliability is possible with its simpler design.

    The 2002 Cadillac Seville STS is the world's first production car with this leading-edge active suspension.

    Magnetic Selective Ride Control will debut in 2003 as standard equipment in the 50th anniversary Chevrolet Corvette. The system also will be optional on other 2003 Corvette coupe and convertible models, except the Z06.

    A video explaining the tech.. http://www.youtube.com/watch?v=HLhC3Em1JrA [youtube.com]

    • by pthisis (27352)

      magneto-rheological fluid-based actuators

      The STS-type hydraulic reactive systems are discussed briefly in the article:

      While active suspension is nothing new (at least, not for cars), it has previously mainly been integrated into hydraulic systems. According to the Eindhoven researchers, however, hydraulics can't react as quickly as their electromagnetic system, and therefore can't match the smoothness of its ride.

      • by Sporkinum (655143)

        I couldn't really tell from reading the article what methed they used for damping, other than is was electromagnetic. The Delphi system is electromagnetic in the sense that a coil around the tube of the shock creates a magnetic field that stiffens the the MRH fluid in the shock. It can do that within 1 millisecond, which I would think is sufficiently rapid. If the Eindhoven system is a free floating linear motor, it should be capable of a wider range if dampening though. I am not sure how it would work when

    • by timeOday (582209)
      Sounds like a cool system, but it is limited to modulating the dampening, and the springs are still just passively pushing on the road, not knowing if they ought to be pulling to suck up a bump or pushing to counter body roll.
  • I worked for Bose back in 2005 and they were researching something like this. They were partnering with GM at the time but I think it fell out because the system was too heavy. There's a video floating around on YouTube of a car jumping over a bump using the Bose system.
  • I wonder what the price tag would be. Of course, if you never have to replace them that would be a plus.
    What I would really like to see is shocks that could generate electricity that recharge the battery in a hybrid/electric vehicle.
    It could probably work somewhat akin to those generators that harness power from ocean waves. Not sure how much power you could get from the motion generated by 4 shocks moving a few inches in each direction.

  • You are correct; No two people have an identical opinion in ride quality, and none have the ability (as far as I know) to quantify improvement. So, they fit the cars with devices which monitor travel of the body during test conditions and compare that to the travel on stock suspension.

    60% improvement will be 60% reduction in body travel compared to stock mechanical suspension under test conditions using body travel as the metric (or some such).
    • by ArhcAngel (247594)
      Since this is /. it requires a car analogy.

      No two people have an identical opinion in ride quality, and none have the ability (as far as I know) to quantify improvement.

      Because if everyone could GM would never be able to sell any Chevrolet vehicles. Look! A car analogy AND flaimbait in the same post.

  • didn't even read the article?

    "The 60 percent ride improvement figure was obtained when a single wheel equipped with the system was mounted on a laboratory testbed that simulates road conditions. "

  • I wish I had thought to patent this idea when I had...when I was ten years old. *sigh*
  • My guess is that one of the following number is used:

    - average *acceleration change* as felt by passenger,

    - average energy transfert in body,

    on a standard bumpy road.

"Why should we subsidize intellectual curiosity?" -Ronald Reagan

Working...