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Electromagnetic Automobile Suspension Demonstrated
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."
I'm pretty sure Bose did this at least 4 years ago: http://www.bose.com/controller?url=/automotive/bose_suspension/index.jsp
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.
Working...
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.
rage, rage against the dying of the light
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.
Not true. As cars have gotten more complex, they've also gotten more reliable because electronics allow greater precision and control. Problems per mile has been going down for the entire industry, and the most complex cars (hybrids) are among the most reliable.
Remember carburetors? Mechanical throttle cables? Tune-ups every 3K? Automotive electronics before body computers?
--srj/mmv
Actually us pavement engineer types do this all the time. Basically the input to the function is the profile of the pavement measured by a pavement profilometer which essentially captures pavement elevation about every 6 in or so. (http://www.dynatest.com/functional-rsp.php) Then this profile is fed through an algorithm that models the response of a hypothetical "quarter car" (basically a spring above a tire to simulate the amount of movement experienced by something on the axle). This measurement is called the International Roughness Index and it has been correlated to "Ride Quality" perceived by highway users. It is not a perfect measurement but it is used quite frequently to help decide pavement projects. if you are more interested.... http://en.wikipedia.org/wiki/International_Roughness_Index http://www.umtri.umich.edu/content/LittleBook98R.pdf So for this thing they would need some other model to calculate the "movement" induced by road profile on the vehicle much like IRI. Once you have that you could correlate it to Ride Quality, have they done that? That is the question...
Good for, you've got an anecdote. Go back through the years of statistics that the NHTSA maintained on recalls and incidents; Toyota's trouble stirred much of this to the surface and it's easy to find. Note how high SUA issues and recalls were.
You're driving the wrong cars, then. Electronic throttles have been well worked out on, well, just about everything from supercars on down. You'd think that, if mechnical throttles were better that someone---Ferrari, BMW, whomever---would be using them. They're not.
Again, I point to the recent Toyota SUA incidents as a counterpoint. It was proven that most people don't step on the brakes hard enough to overcome the engine, or that they pump the brakes, or that they do something similarly stupid. SUA rates were quite low for cars with brake/throttle override. It's actually a very simple, very elegant idea that works for most people. Oh, sure, it makes heel/toe and left-foot braking harder, but outside of rally drivers that sort of behaviour is asking for trouble.
You're under the impression most people drive on a racetrack. Most people don't.
Yes, that's true. And the "interference with driver decisions" is why road accident and fatality rates are at their lowest ever, despite there being more cars on the road than ever. Half the people on the road are, by default, below average. Most aren't all that skilled. Personally, I'd like to avoid getting hurt because someone isn't 31337 enough to induce just the right amount of wheel lockup to not skid into me, or apply just the perfect amount of opposite-lock.
But they work well for most people under most conditions, allowing them to retain steering control (for ABS) or skidding uncontrollably (ESC). Yes, if you're a rally-racer they should be disabled. Most people aren't. You seem to miss that point
My, aren't we elitist? Look, good for you that you can drive your home-built Caterham at 10/10s on the track and can tear down and rebuild and engine in two hours. I'm glad for you. But you need to realize that most people are not you, and never, ever will be you. So just keep sneering to yourself.
But don't assume that electronics don't make cars more reliable, more efficient, safer, cleaner and faster for 99% of the people out there who don't give a shit about throttle oversteer or adjusting camber between laps. The facts are a) cars have more electronics, and b) those cars are thusly better in every way for everyone who isn't a gearhead.
This thread started because someone offered the usual "Oh noes, more stuff to break!" fallacy which has been proven, time and again, to be utter crap. It wasn't started as debate on automotive purity.
--srj/mmv