Archive for February, 2010

The Sound of Silence

February 19th, 2010 Comments off

Seems I’m linking back to myself a lot lately…

Last year, I bored you with a description of a speaker embedded in a car’s exhaust system, used to help tune the exhaust note.  Well, it turns out Honda/Acura has been doing something similar for a while, only using the speakers that are already inside your car.

They call it Active Sound Control, and the system uses anti-phase sound waves (which I also previously talked about) to cancel the “unwanted” engine noises from the cabin, while allowing the more pleasing snarls to tickle your eardrums when the throttle is to the floor.  (The irony here is that I’ve yet to come across a Honda or Acura that actually produced any sound which could be described as aurally exciting.)  Honda is offering the technology on their new Crosstour (a car which I’m oddly intrigued by), and Acura on their TSX, RL, and ZDX.

This is cool technology.  But I can’t help but think it’s just technology for technology’s sake – sort of a Rube Goldberg device for correcting the deficiencies of their engine designers and exhaust system engineers.  (Of course, it wouldn’t be the first time Honda employed an over-engineered solution for a simple taskbut that time I was impressed.)

Maybe I’m wrong. Perhaps using the stereo to cover up engine sounds is a more efficient solution to unwanted cabin noise than a well-designed engine, proper attention paid to exhaust tuning, a chassis developed with NVH in mind, and sufficient levels of sound-absorbing insulation.  (For what it’s worth, GM chose the insulation route with their Quiet Tuning technology in their Buick brand.)

In my opinion, a more holistic approach would be better than Active Sound Control.  As in most cases, it’s better to treat the source than to mask the symptom.

Somebody KERS!

February 14th, 2010 Comments off

Last August, I posed the question, “Who KERS?” in regards to the limited success of the Kinetic Energy Recovery System employed in the 2009 Formula 1 season, and the elimination of the system for 2010.  Well, it turns out that at least one of the systems developed by an F1 team will in fact live on.

As recently described by AutoBlogGreen, Porsche is utilizing the Williams-developed flywheel-based energy storage system in its 911 GT3 R Hybrid.  The 911 GT3 R is the race version of Porsche’s bread-and-butter 911.  The hybrid system leaves the conventional 480-hp flat-6 powering the rear wheels untouched, while adding a pair of 80-hp electric motors to each of the front wheels.

Porsche 911 GT3 R Hybrid

Porsche has always done things a little differently than other automakers, at least with respect to the 911.  Instead of competing in the horsepower wars using 8-, 10- and 12-cylinder engines with massive displacement, they’ve continually developed their horizontally opposed 6-cylinder combined with lightweight (and often exotic) materials to maintain their competitive edge.  Until just over a decade ago, this engine was still air-cooled, in contrast to literally every other automaker’s water-cooled powerplants.  And even now, in a triumph of engineering over physics, Porsche still hangs the motor way out back behind the rear axle.  So it comes as no surprise that they’ve taken the less-traveled path of using a flywheel (instead of a battery) to recovery the energy from braking.

In the simplest terms, the system works by the front-axle motors acting as generators to convert the kinetic energy of the spinning wheels to electrical energy under braking.  The electrical energy is then converted back to kinetic energy at the flywheel (which is essentially another electric motor), as it spins at speeds up to 40,000 rpm.  Under acceleration, the flywheel then acts as a generator, converting the kinetic energy of its spinning mass to electricity, which is routed to the front-wheel motors, where it is converted back to kinetic energy to help power the wheels. (One thing I’ve often wondered in systems like this is – why all the conversions? You want kinetic energy to move the car, and with a flywheel you’ve got a kinetic energy storage system.  Seems like there’d be fewer conversion losses if you could skip the electro-part of the electro-mechanical system, and just connect the flywheel to the drive system by an intelligently activated clutch or viscous coupling.  I’m sure the hybrid system designers out there could give me countless reasons why this wouldn’t work, however.)

And finally, am I a hypocrite because I like this car so much more than the BMW X6 ActiveHybrid, which I criticized here?  Of course not.  BMW has taken a conventional fuel-efficient technology and applied it to a mass-market car solely for performance purposes, with almost no efficiency benefit.  (Plus, the X6 is ugly.)  Porsche, on the other hand, has taken an unproven fuel-efficient technology, and applied it to a limited production race-car as sort of a rolling laboratory to spear-head the development of this new technology, before potentially applying it to its road-going cars.

And although I (like many others) question the feasibility of flywheels as the energy storage solution for mass-market hybrid vehicles, people also once criticized the throwing-a-dart-backwards handling characteristics of the rear-engined 911.  And by most measures, Porsche has been successful with that effort…


February 9th, 2010 Comments off

Back in December, after driving through the Mid-Atlantic Blizzard of 2009, I extolled the virtues of all-wheel-drive, in both inclement and sunny weather.

My Audi (Pre-Extraction)

And now, having made it (at least most of the way) through the Mid-Atlantic Blizzard of 2010, I am again grateful that all of the cars in my household are driven by all four wheels.

But, while digging my Audi out of its icy crypt after this past weekend’s wintry blast, I began to grow bitter as I was repeatedly compelled into service to help extract some wayward traveller’s ride from the unplowed street in front of my house.

So, to help commemorate my efforts (not to mention my sore back) in putting up with helping my fellow man during this storm, and with all due apologies, I pass on to you some of the more illuminating remarks that were shared with me as I stood outside in the snow, shovel in hand.

“I don’t understand why my traction control isn’t working!” (Exclaimed by a man who had driven his Lexus ES350 into the deep snow just a bit outside the two hard-packed tracks that designated where the road is.) Sir, it is working, but your front-wheel-drive fancy Toyota isn’t the Mach Five.  Your car can’t drive over open water, nor can it scale vertical buildings.  Similarly, it will not move once you ram it into 2 feet of snow.  And please – stop spinning the tires.  You’re slinging slush into my face while I try to dig you out.

“Hey, are you stuck?!” (Smugly asked by a couple in a Subaru Forester, driving past me and the Lexus driver.) No, ma’am.  We’re not stuck.  I frequently hang out in the middle of snow-covered intersections, with my head under a Lexus, chatting with old guys in golf pants.  Oh, and this snow shovel in my hand?  No idea how that got there.  …Oh, OK – maybe the Subie drivers weren’t quite as smug as I make them out to be.  (Though, I sure would be, if I were them!)  Truth be told, in an effort to disassociate myself from the Lexus driver and give the Forester folks a nod of vehicular approval, I immediately pointed to the Lexus and replied, “Well, HE’S stuck!”  In the end, however, the Subaru just kept on going without stopping to help…

“Wow, I’m not going ANYWHERE, am I?!” (Shouted by a Mercedes C300 driver, whose rear wheels spun hopelessly as she sawed back and forth on her steering-wheel.) No, ma’am, you’re not.  Unless I get out of my vehicle (which you’re now blocking) and push you, along with the help of several other frustrated folks who actually took the time to determine the state of the roads and the suitability of their vehicle in these conditions.  And please, once we get you going, don’t stop again.

“Which way are they facing?” (Posed by the same Merc driver that offered up the previous quip, in response to me advising her to aim her wheels forward when we started to push.) Really?  How little awareness do you have of what’s going on with your car that you don’t know which way you’ve turned your steering wheel?  Also, please hang up your cell-phone – we’re trying to help you.

“Hey, can I borrow your shovel?” (A seemingly unburdensome question asked by a taxi driver who sat in the road, a single rear wheel on his old Ford Crown Vic spinning impotently in the slush.) Oh, this shovel?  The one I’m using to unencase my own car?  Sure, go ahead.  I wasn’t really … using … it.  (OK, actually, I was getting tired, and wanted to take a break, so I offered the shovel.)  Only Mr. Cab Driver intended for me to dig him out, while he continued to rock the car back and forth.  Only there was no rocking.  The pitiful traction offered up by that rear-wheel-drive car with bald tires and no limited slip differential was almost comical.  He didn’t budge until a few passers-by joined me in shoving him down the street.  …Come on, you’re a professional driver.  You do this for a living.  You should know better!

…OK, perhaps I should have more patience with my fellow drivers.  (And honestly, I’m not really the jerk that this post may lead you to believe.)  …Maybe modern cars have become so good – so capable of isolating us from the road and everything around us – that we feel invincible when we’re behind the wheel, and we forget what the limits are.  …Or maybe we just never stop and think before hopping behind the wheel in the first place.

Tweeting Our Way Out of Oil Addiction

February 3rd, 2010 Comments off

The year was 1987. Ronald Reagan was president, The Simpsons appeared on TV for the first time, and disposable contact lenses became commercially available.  …That was also the year I became a licensed driver.

When I was a teenager, reaching the age of licensedom was the most anticipated and celebrated event in a young man’s life.  No more having your parents shuttle you to meet your friends – or your date – on a Saturday night.  With that little piece of plastic, you could go wherever you wanted, whenever you wanted … as long as it was before dark.  (You had to wait another year for completely unrestricted driving privileges.)

According to a story last week in the Washington Post, the trend of teenagers applying for a driver’s license as soon as the clock strikes “16 years” may be changing.  According to the story, in 1998 nearly 45% of 16-year-olds got their driver’s license.  In 2008, that percentage had dropped to just over 30%.

Why the apparent decline in interest among teens to jump in their car and drive?  Well, according to the Washington Post story, one contributing factor is social networking.  Back in the day, if we wanted to … social network … with our friends, we had to go see them.  In a pinch, we could talk on the phone.  (Three-way calling was cutting-edge technology!)  But then mom would have to use the phone, so we’d have to to hang up – and break the 3-way-calling-chain that had connected all of our friends.

Since then, we’ve seen cell-phones, broadband, and social networking come into existence and become mainstream.  Teens spend countless hours on Facebook, Twitter, and texting (or otherwise instant-messaging) with their friends.  And when they do this, they’re not driving.  (Well, OK, some of them do text-and-drive.  Which is dangerous. And hard.)  In fact, some teens would actually prefer to be chauffeured around by dear old mom and dad simply so they can continue to OMG and LOL with their BFF!

When a friend of mine recently told me he offered his teenage daughter a choice – a new car, or an iphone … and she chose the iphone, I began thinking, “I wonder what the impact that this phenomenon might have on the amount of fuel we use in our cars is, compared to the impact of, say, hybrid vehicles.”  Let’s assume there are about 10-million teenage drivers in the U.S. – a reasonable guess.  Assuming about 2.5-million of these are 16 years old, then the Washington Post article suggests that about 375,000 of these kids who would’ve gotten their licenses 20 years ago now choose not to.  If each of these kids would have otherwise driven 10,000 miles a year at an average of 25 mpg, that’s about 150-million gallons of gasoline per year that we’ve avoided burning.  Conversely, if Facebook didn’t exist and these kids still got their license and all drove 45 mpg Prius’s (without the faulty accelerator), then we’d only save about 67-million gallons of gasoline each year (compared to the 25 mpg baseline).  Wow.

OK, so my assumptions are arguably faulty.  But, they’re based in reality. And the conclusion? Twitter is more than twice as effective as hybrid technology at reducing fuel use in vehicles.

You heard it here first, folks.  But please – don’t retweet it.