Tuesday, March 23, 2010

Wrong pedal, dummy.

So you go to move your boss's car, and it rockets into a stone wall, crumpling the front end like an accordion. Hmm. A paint touch-up pen isn't going to cover this up, and your boss is sure to be mad when he notices it.

But wait! Your boss's car is a Prius!
A housekeeper was driving the car at the time of the accident. She told police the vehicle accelerated on its own as she eased forward down her employer's driveway, causing her to crash into a stone wall on the other side of the road.
Except investigators can often get to the truth of these things even without "black box"-type data from the car's computer (which has been capable of finking on you for a long time in some cases; Caddy mechanics, for instance, have known if their customers were speeders for almost twenty years now.)

In this case, however, there was no need to resort to esoterica like examining brake light bulb filaments under a microscope to see if they were carrying voltage at the time of the wreck; the little Japanese hybrids are only slightly less computered-up than the Joint Strike Fighter. Local po-po and NHTSA investigators whipped out the electronic Ouija board for a seance with HAL-san and, sure enough,
there was no indication of brake compression as the car headed toward a stone wall. Rather, the accelerator was pressed 100 percent...

Now that the reports are all filed, however, what does our heroine claim?
Marraccini said that he spoke with the housekeeper about the findings of the investigation, but she remains "very passionate about her statement."
Well, of course she does. To do otherwise would be admitting that she was either a liar or a klutz in front of millions of people. It wouldn't surprise me at all if her memory had edited the whole experience by now to the point that she actually really does believe she was stepping on the brake.


og said...

I hear the argument constantly that "we need to go back to the "Good old days" when cars were less computerized. yeah, right. Everyone wants to be free of eeevil computers but nobody wants to do the maintenance or pay anyone else to do so.

OTOH, I usually have an OBDII reader in the car, that I can use to erase the OBD data at a moment's notice. Not everyone is similarly equipped.

Me, I'm of two minds on this; I dislike that the equipment is tattle-enabled, but I like that it, for instance, allows me to drive my car for a third of a million miles without a new set of points. I would say, the Ford and GM electronic ignition equipment of the 80's would have been a good place to STOP, but having futzed with them for many a year, I'm no fan of carburetors and I like the reliability that multi-point injection delivers.

Tam said...

Yeah, I don't miss that old Russian Roulette feeling of pulling a carburetted car into traffic the first time on a really cold winter morning... Is it going to accelerate? Or is it going to cough and die when I give it a big belt of throttle? Roll them bones!

Anonymous said...

I'm sure that nearly all of these cases are caused by a short-circuit between the headphones. But, if cars were regulated by OSHA, there would be a big red EMERGENCY STOP button on the dashboard.

If there is any way for the computer to get in the way of the brake (isn't that how anti-lock brakes work?), there really does need to be a second path that will guaran-damn-tee that the brakes are applied when needed. This becomes as much a user-interface issue as an electrical/mechanical engineering issue.


og said...

ABS just dumps the system pressure momentarily if it senses the wheels locking. Many ABS systems will self defeat if you first tap the brake and then SMASH IT. It sees that as a sensor failure and turns the ABS off. You can also manually override the ABS by replacing the fuse with a switch and a fuse wired in series; off means off and on means ABS. None of this means anything to OBD, which has a throttle position sensor and a brake pedal position sensor. ABS is independant of the OBD system in most cars.

Carteach said...

OBDII is independent of the 'Black Box' recorder system. Erasing the adaptive strategy and codes will not erase recorded driver input data.

There are 14 high level Toyota technical investigators in the nation. When someone plows a wall with a Prius (or spends 20 minutes at 94mph while talking to 911), Toyota pulls the data and sends it to each of these folks. They are not allowed to talk to one another, and must analyze and report in no more than one hour. Toyota relies on the consensus answer to guide investigations.

The systme in the Prius is good... VERY good. They are even tied into the four seat pressure sensors used for the air bag system. They record not only throttle demand, but brake pressure percentages, and how much your butt lifted off the seat when you stepped on the pedal. They can even tell when you lean over to fart.

Not every vehicle is as fully mapped and recorded as the Prius, but many are.

og said...

Yeah, the exploder only has obd and anti theft. The obd device I use is a little piece of hackware that will talk to most things, but I never tried it on a prius. Those are pretty complex machines.

Don M said...

The unsaid part of this is that car controls have really bad human factors design. If you were to do it today you wouldn't put two primary controls with essentially opposite function, right next to each other, on the floor where you couldn't see them, and insist that people operate them with their feet.

Early versions of the M-1 Carbine had the "SAFETY OFF" and "RELEASE MAGAZINE" buttons right next to each other, with predictable results. Just as you were getting ready for some shooting you dropped the magazine...

Of course the Government now requires that configuration for all cars.

staghounds said...

There is no doubt that she believes it, because she really did believe it at the time.

It takes a LOT of training, practice, faith, and experience to get pilots to trust the instruments they can see and test.

And sometimes they still don't.

You could waterboard this lady and she would swear she was stamping on the brake.

Drang said...

I suppose I'm evil because my first thought was "How well does the housekeeper speak English?" and "Did they check her green card status?"

I once spent a cold weekend stranded in Korea's Chorwon Valley because the "brain box" died on my M880 (camo-painted Dodge pickup truck). The sort of thing that makes one distrustful of electronics being vital to vehicles going. No doubt irrational and outdated and all that, but I keep wavering about telling Mrs. Drang we should keep her Dad's '63 Nova, for after the Solar flare and/or EMP bomb...

WV: divityna. "Honey, Divityna says the Prius tried to kill her."

Tam said...

"I suppose I'm evil because my first thought was "How well does the housekeeper speak English?" and "Did they check her green card status?""

They only do that to politicians they don't like.

theirritablearchitect said...

I've been saying the same thing about cars since 1988, ditch the damned automatic transmission, period.

You will NEVER read of another story like this in the news if the third pedal is in every car on the road.

A side benefit is that there will be far fewer dolts who are actually on the road to run you over.

Yes, you can all call me a snob now, I don't care.


Tam said...

I drive a manual.

Most folks out there are mindless drones who have difficulty operating the six major vehicle controls (gas, brake, steering wheel, iPod, makeup mirror, and cell phone) without adding the complication of clutch and shifter.

theirritablearchitect said...

Oh, I know yer Kraut roadster is a stick; I'm just sayin' that all vehicles should be so equipped, and if one can't get competent with that set of controls, I'd hedge a bet that that person can't walk and chew gum at the same time either.

Joanna said...

architect: I see your point, but here's a caveat: Under your rules, folks like my dad (paralyzed lower left leg) would have to shell out extra money for modifications and hand controls in order to drive.

Fuzzy Curmudgeon said...

I used to love me a manual.

Then I got old and my left knee started having a tendency to lock up on long trips.

I haven't owned a stick since 2000, and I'm not going back. But I can also walk and chew gum at the same time, so I don't think I'm the target demographic for this proposal :)

Leatherwing said...

A few years ago I worked as a valet for a steak restaurant. The manager actually hired two peoepl to work as valets that could not drive a manual transmission. There were several nights when three people were getting paid, but only one was working.

Anonymous said...

The data recording is not dispositive.

The Prius doesn't directly connect the brake pedal to the brake. It uses fancy technology to reclaim energy. If pressing the brake pedal doesn't electronically active the brake, why would you expect the data recorder to record it? You'd expect the opposite - no recording of braking.

theirritablearchitect said...


I'm being my usual smartass self, and doing a fair bit of the LeftLibProjection schtick, there.

I actually own one vehicle that's an automatic, and it works perfectly, with no sudden acceleration, and I know why.;)

og said...

I drive an automatic, as anyone who has to drive in Chicago traffic eventually will. Rowing a clutch (I did it in my Ford Probe for 270,000 miles) around Chicago expressways will let you appreciate a mushbox in a hurry.

For fun, though, nothing beats a stick.

Anonymous said...


In principle, I agree with you. I told my kids when they started drivers ed that you DRIVE a stick, but you AIM an automatic.

However, with my blown legs (I am in my wheelchair as I type this, but rehab is progressing slowly) without hand controls I could not possibly get around, and a stick is just out of the question.

cap'n chumbucket

Tam said...


"I drive an automatic, as anyone who has to drive in Chicago traffic eventually will."

I did the grinding ATL commute (100mi/day) with a manual, and boy did my clutch hand get sore... ;)

og said...

yeah, it's rugged. People who drive 15 miles to work will never understand. Had a friend who drove a dresser back and forth to Ford every day, 35 miles, and he had forearms like Popeye.

theirritablearchitect said...

Been doing 63 miles a day for almost a decade in my manual...and wouldn't have it any other way.

Anonymous said...

Tam said:

"It wouldn't surprise me at all if her memory had edited the whole experience by now to the point that she actually really does believe she was stepping on the brake."

Her memory didn't have to edit it. Her brain skipped the step where she was supposed to take her foot off the gas and put it on the brake. Nothing to edit. She really does think she was stepping on the brake, and there's no memory otherwise for her to suppress.

When the original "unintended acceleration" investigation on Audis finally ended after, what, three years?, they had to conclude that it was 100% driver error. Car and Driver magazine even did their own study, in which they employed the services of a professional race school driving instructor. The professional race school driving instructor explained that fully 30% of *enthusiasts* make the same error under stress, which is why the instructor had his own brake pedal on the passenger side of the car for driver training. It was so common they even made videos of the student racers who swore up and down that they were stepping on the brake, not the gas. The technique that was most successful in making students aware of their error was for the driving instructor to reach over and physically yank the student's leg off the pedal.

If 30% of *enthusiasts* make this error under stress, you'd think word would get around, no?

But, I suspect it's politically incorrect to even mention that old study, because it also found something far less palatable and politically incorrect than "100% driver error". You see, the results of the study were very quickly and quietly swept under the rug when it was found that 85% of the reports of "unintended acceleration" were made by women. Not only was that not an acceptable result, it may even be so unacceptable, that the report might not be used in the coming court case.