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A Car With A Mind Of Its Own 1416

mindriot writes "When Hicham Dequiedt, driving on a highway between Vierzon and Riom in central France in his Renault Vel Satis this Sunday, was overtaking a truck, his car began accelerating to 120 mph on its own, apparently due to a defect in the cruise control system. Stomping on the brakes proved pointless and, having a magnetic card for a car key, he could not cut the ignition. After calling the police from his cell phone who then attempted to clear the streets of any danger to him, in what he described as the most fearful event of his life, he raced down the highway for another hour before finally managing to stop the car. Read about the incident here or, in more detail, in this article by the German 'Spiegel' (translation). The case is still under investigation. Are we putting too much trust in the increasing number of electronic systems that our lives depend upon?"
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A Car With A Mind Of Its Own

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  • by jargoone ( 166102 ) * on Tuesday October 05, 2004 @12:13PM (#10440459)
    Yeah, getting the car into neutral would be my first thought, too. This car probably had that option. However, some newer, fancier cars also have the gear selection electronic. The BMW 745 comes to mind. I suppose it's unlikely that two systems would fail simulatneously, but who knows?
  • Amen (Score:5, Interesting)

    by Intraloper ( 705415 ) on Tuesday October 05, 2004 @12:13PM (#10440463)
    Seems simple enough to just shift into neutral and let the engine blow. Unless I'm missing something.
  • by TopShelf ( 92521 ) on Tuesday October 05, 2004 @12:14PM (#10440477) Homepage Journal
    Something smells rotten with this story. Stomping on the brakes didn't do anything, but as he approaches a toll booth, the brakes suddenly work and he's able to stop the car??? Catastrophic system failures don't often repair themselves...
  • by IANAL(BIAILS) ( 726712 ) on Tuesday October 05, 2004 @12:16PM (#10440494) Homepage Journal
    The article says he tried stepping on the brakes, but that had no effect on the cruise control... that's usually enough to break the cruise and return acceleration control to the driver, but it sounds as though there was a problem with whatever the electronic link was between the brakes and the cruise. The article doesn't say so, but did he simply try turning OFF the cruise control manually to get the car back under his control?

    I also seem to remember years and years ago reading (i think it was in readers digest) about a woman who had the same problem with her car - she had to 'drive' it until the car ran out of gas and then stopped on its own. No cruise control there, so problems can occur with or without all the new technology out there.

  • Re:Transmission? (Score:1, Interesting)

    by Anonymous Coward on Tuesday October 05, 2004 @12:20PM (#10440578)
    That particular car mentioned is a high tech model with completely automated shifting system, hence making the question about too much reliance on computer controlled system a very valid one...
  • by maxchaote ( 796339 ) on Tuesday October 05, 2004 @12:20PM (#10440582)
    This is why all those high-tech gadgets of the world of tomorrow in classic Sci Fi had "manual override"s.
  • by linuxtelephony ( 141049 ) on Tuesday October 05, 2004 @12:23PM (#10440635) Homepage
    I wonder if the electronic transmission has "safety sensors" that won't shift to a lower gear if it might cause engine damage. If so, even if you put the selector down to the first gear, the computer would override the driver in order to protect the engine.

    Hmm, the computer overriding the human for self-preservation. That could be interesting.....
  • by Anonymous Coward on Tuesday October 05, 2004 @12:23PM (#10440642)
    Well, most brake systems are such that you don't lose power brakes immediately, though you will almost certainly lose anitlock. Now depending on the weight of the vehicle, it is actually easier to steer the vehicle at high speeds. As for the drive by wire systems, I believe that will require a legislative change since current requirements are for a mechanical linkage for the steering. And folks depending on how important it is to stop use the old rally trick of the hand/parking brake.
  • by Cro Magnon ( 467622 ) on Tuesday October 05, 2004 @12:24PM (#10440651) Homepage Journal
    If I hit one button it sets the speed, and the other one accelerates to an already set speed. I hit that one, and it got stuck and instead of accelerating me to the speed I wanted, it kept on accelerating. A quick tap on the brakes deactivated it, but it was still unnerving.
  • by qqtortqq ( 521284 ) <<mark> <at> <doodeman.org>> on Tuesday October 05, 2004 @12:24PM (#10440659)
    I helped out on an accident investigation a few months ago- there were probably 400 yards worth of skid marks, the the driver of the vehicle hit the center barrier 4 or 5 times. I was trying figure out how those skids were left (she wasnt doing 600mph) when someone looked in the car and saw a sandal stuck under the gas pedal, pinning it to the floor. The back wheels were locked up because she was on the brake, but the engine kept the power to the front wheels, keeping the car in motion. Must have been a hell of a ride.
  • by cbelt3 ( 741637 ) <cbelt&yahoo,com> on Tuesday October 05, 2004 @12:25PM (#10440686) Journal
    This happens in Hardware, too, guys. Envision a combined catastrophic failure- automatic transmission locks in gear (they do, ya know- it's basically a hydraulic switch that gets gunked up), accelerator cable jams in full-on position (again, it CAN happen). Oh, and to add insult to injury, the power switch on the bad boy is jammed somehow. Once you are up to speed (say 100kph plus), the parking brake (which only acivates the rear brakes) will happily burn up the rear brakes, if it works at all (most automatic transmission drivers never use the parking brake, and it's not adjusted, so full pull/push will only result in minor or no brake application). Pushing on the transmission selector doesn't do anything because it's jammed internally with lots of hydraulic pressure. Holding down the brakes will cause 'em to burn up if the engine has enough HP to overcome them.

    I can personally recall a wild ride in a manual transmission car where the accelerator cable stuck in full-on. I had the presence of mind and fortune to shut the engine off before it spooled past redline, but in traffic it was an interesting experience.

    As we get more into software driven automobiles, the opportunity for failures like this continue to climb. For example --->

    If Microsoft made cars, and other true stories [slashdot.org]

  • Re:Emergency Brakes (Score:0, Interesting)

    by Anonymous Coward on Tuesday October 05, 2004 @12:25PM (#10440689)
    Yes, it can! Brakes are WAY more powerful than engines. A small car like that Renault has the equivalent of 600 or 700 hp in the brakes. If you read the story, that's how the driver eventually stopped the car -- he hit the brakes!

  • by Oddly_Drac ( 625066 ) on Tuesday October 05, 2004 @12:26PM (#10440704)
    "If you can't steer and/or stop your car with the power off, you need less car."

    Did you mean with brakes, or by hand? If the latter, I'm going to be really polite to you.

    "Using electric brakes with metallic pads means no brake fade, ever, up to the point where you warp your rotors. There's no brake fluid to take on water and boil, not necessarily in that order."

    Fade is gaseous buildup from the pads ablating against the disc, which is why you do graduated braking on a non-fancy car, but personally I wouldn't trust a solenoid to do the force multiplying work of a caliper.

    As for the brake fluid taking on water...if you have a non-tight hydraulic system you'll be screwed anyway, let alone getting to the point where you have water in it. Compare the relatively low tech and _reliable_ cylinder and caliper system with the voltages/currents required to produce braking forces and you'll probably notice that there's going to some power applied.

    "unreliability of automotive hydraulic systems."

    Probably _the_ most reliable portion of the average motor car, if maintained and kept in good repair and not driven with utter faith in the ability to tailgate other drivers at 80mph. Most accidents involving brakes are people locking the wheels at speed.

  • Re:Amen (Score:1, Interesting)

    by Anonymous Coward on Tuesday October 05, 2004 @12:26PM (#10440713)
    Engines have Rev Limiters that will stop the RPMs from going to a point of an Engine Blow.

    The car would have gone into neutral. There is more to this story.

    SP --- Doubter but can't get to the article.
  • by Katharine ( 303681 ) on Tuesday October 05, 2004 @12:27PM (#10440724)
    I thought it sounded odd also. Reading the Google translation of the German article, it sounds like first he managed to remove the smart card (after several attempts) and then was finally able to stop the car with the brakes.

    Maybe removing the smart card disengaged something that was preventing the brakes from working properly-- could an automatic anti-skid system or something like that have added to the problem?
  • This happened to me. (Score:4, Interesting)

    by ccandreva ( 409807 ) <chris@westnet.com> on Tuesday October 05, 2004 @12:27PM (#10440730) Homepage
    My mom's '83 Oldsmobile Cutlas did this.
    I had my licence maybe less than a year, and was driving home from the movies at night on the Boston Post Rd in Westchester county, NY (2 lane street, storefronts on either side.)

    All of a sudden the gas pedal went down to the floor on it's own, and the car starts to accelerate from about 30, through 50 and going. Hitting the break did not disengage the cruise control, and breaking a floored car doing 50 does - absolutely nothing.

    Just as I was about the turn off the key, the pedal comes back up. The whole way home the car did this. I still remember getting home, being asked what was wrong, and saying "Your fucking car tried to kill me." - this was the first time I swore (on purpose) in front of my parrents.

    Next day we take it to the shop, and the mechanic's reaction was "Oh yeah, they do that." Evidently the cruise control wires, mounted on the turn signal lever, woudd fray and short out. Part of the design was the Resume button had priority over the break cut-of switch, so when Resume shorted, you were screwed.

    I've met three other people who owned this car, and had the same thing happen to them. One guy, as soon as he said he'd had an 83 Cutlas, I asked "Did it ever go Flying Dutchman" on you, and he knew exactly what I met. His started revving itself next to a Cop at a traffic light. He just got out with his hands up, saying "It's not me, it's the car !", as the car sat there revving itself.
  • by Beardo the Bearded ( 321478 ) on Tuesday October 05, 2004 @12:27PM (#10440731)
    No, embedded systems have a Watchdog Timer.

    Basically, if you've fucked up the code, it reboots the device or skips a line of code after a set amount of time. It's usually a few seconds, but newer chips can have a delay of a few minutes. (The one I'm working on today goes up to 4:28.) If you do anything with a chip that nobody will ever see again, you enable the watchdog timer. It's pretty easy to incorporate and lets your system recover from lockups or hangs.

    I agree that something is fishy here. I am curious as to why he didn't jam the car into 1st and yard on the e-brake like his life depended on it. Don't people learn to drive anymore? Further, don't they have runaway lanes in France? We've got them all over the place here - they're designed for big rigs, but a small car would be more than welcome if you had a problem like this. You drive up a steep unpaved hill into barrels of water. You stop.

    I'm an Electronics Engineer and I'd never trust a drive-by-wire car. Things go wrong; you have to have some sort of mechanical over-ride for a life-critical system like a car.
  • This story reminds me of the day we went to brussels in a renault megane diesel and the motor began to exhaust fume so we stopped and guess what, after turning off the key, the engine continued to function ! After a few minutes, it started to burn oil and that made a large cloud on the road. It finally stopped when there was no oil with a strange sound and the engine was dead.

  • by drinkypoo ( 153816 ) <drink@hyperlogos.org> on Tuesday October 05, 2004 @12:28PM (#10440752) Homepage Journal

    If I turned the key off too far I'd deserve what I got. However my car requires that a I push a little button down to turn the key far enough to lock the steering, probably for that reason. However, it's a Nissan, and their engineers actually understand what they're doing. (Shit, even my distributor can only be installed one way. I wish more engines were like that.)

    It's not that I'm high and mighty, it's that I consider driving to be a privilege and a responsibility.

  • Re:Emergency Brakes (Score:5, Interesting)

    by swordboy ( 472941 ) on Tuesday October 05, 2004 @12:36PM (#10440876) Journal
    A couple of things to consider:

    - The e-brake / parking brake is usually installed on the rear wheels which, due to the pesky laws of physics, only account for about 10 - 20 percent of braking power, depending on the car's configuration.

    - At high speeds, it is very possible to over power the brakes. Mind you, auto manufacturers are very careful about sizing the brakes at a much larger power capacity than the engine. This is a no-brainer. However, it is possible to overwhelm the brake materials at very high speeds, causing the braking power to deteriorate. For example, if you ride the brake at 120mph, you'll lose braking capacity. If you then try to stop the car completely, the engine might have more power than what exists in the braking system under its deteriorated state. I had a caliper stick once and it heated everything up so much that I lost braking power on that particular wheel. It wasn't fun.

    So the e-brake would definitely not be a choice in this matter. It should be noted that manufacturers have dropped this term and replaced it with "parking brake" for legal and marketing reasons.
  • Nice Thought But... (Score:5, Interesting)

    by virg_mattes ( 230616 ) on Tuesday October 05, 2004 @12:40PM (#10440950)
    ...if this car had a manual transmission, there'd be no problem. Step on the clutch (why would you downshift instead of just holding the clutch open?), let the rev limiter protect the engine, and step on the brake. Car stops.

    Because of this I'm inclined to believe it's an automatic transmission. Shifting it from drive to neutral will disengage it, and again the rev limiter covers the engine while the brakes stop the car. I'd like to see documentation of any automatic transmission that will refuse to disengage at any given engine or car speed, because that auto company would be wiped off the face of the Earth by lawsuits. I doubt such a transmission exists.

    All in all, I suspect that the same thing happened here that happens in a lot of cases. I suspect he panicked when he couldn't stop the car and since nobody directly told him to shift it out of gear, he didn't think of it. Also, he managed to stop the car using just the brakes (which is as it should be; the brakes should be strong enough to stop the car under full power, assuming they're in good repair), so I further suspect that if he'd been calmer he could have stood on the brake pedal sooner.

    Virg
  • by Naikrovek ( 667 ) <jjohnson.psg@com> on Tuesday October 05, 2004 @12:45PM (#10441022)
    I was in my dad's 1968 chrysler newport (HUGE car) and was driving 65 or so on cruise control. when i got into town the cruise wouldn't disengage and the 290hp motor was too much for the 4 wheel drum brakes to stop. for some reason the car would not go into neutral. i put the car through all the gears and my speed did not change. i cruised through town braking at about 50 and had a huge line of cops behind me by the time i got out of town, and when i finally got to a point of open road where i could think to switch off the ignition (i was 16, gimme a break) i was promptly thrown on the ground and handcuffed.

    one of the officers didn't believe me when i said the cruise control stuck, and asked test the car himself, since it was the only way to prove to him that i wasn't purposely speeding. when he started the car again, cruise was still stuck, and the car was still stuck in gear, and VROOM 65mph. he spun around and hit a tree, steering column peirced his chest and killed him.

    they kinda forgot about arresting me after that. cruise control sucks.
  • by reuben04 ( 740293 ) on Tuesday October 05, 2004 @12:48PM (#10441062)
    It happened to me once too in a honda, it hit 120 before I could get it under control. The weird part was that the button I hit was not to accelerate, but to decelerate. It just kept going faster. Jamming on the brakes didn't shut it off, but it did slow me down. I tried shutting the cruise off and that didn't work. I then tried the master switch on the dash and that didn't work either. I pulled up on the accelerator by placing my foot underneath the pedal, and hit the brakes. I still don't understand why and neither did honda but it promptly shut off. It is a scary thing when you know you don't have control of the vehicle. Sidenote: http://charlotte.creativeloafing.com/news_cover.ht ml [creativeloafing.com]
  • Re:Emergency Brakes (Score:2, Interesting)

    by Big Nemo '60 ( 749108 ) on Tuesday October 05, 2004 @12:51PM (#10441096) Journal
    Amusing detail: accordingly to the description from the Renault site (link in the story), the Vel Satis has *automatic* (i.e. computer controlled) parking brakes...

    I wouldn't buy one even if I could afford it (and I can't). :-P
  • the audi story (Score:5, Interesting)

    by bmajik ( 96670 ) <matt@mattevans.org> on Tuesday October 05, 2004 @01:03PM (#10441277) Homepage Journal
    is bullshit. Audi owners know it well - 60 minutes did a big thing on it and it basically crushed Audi NA's brand image and sales. They renamed their entire model range twice.

    The real cause ?

    On the type 44 cars (Audi 4000 and 5000) the gas and brake pedal are close together to make performance driving easier.

    Dumb shit americans would hit the gas pedal going for the brakes and rear end people at stops.

    CBS fabricated the "expose" on the "problem" completely. Lawsuits were filed and eventually resolved with Audi showing no negligence or fault, but they still changed their pedals in later cars anyway.

  • by Exmet Paff Daxx ( 535601 ) on Tuesday October 05, 2004 @01:09PM (#10441375) Homepage Journal
    This article I found seems to back up his story that the handbrake is electronically controlled as well as the engine and therefore user shutdown is impossible:
    link [channel4.com]:
    an electronic card instead of a key (it remembers your preferred seat, stereo and mirror settings, among other things), a DVD player in the rear - only one, though, rather than the pair you can have in some cars - and an
    electronic handbrake. This last advance dispenses with the familiar lever in the centre console, engaging and disengaging when the engine is switched on and off. There's no danger of the Vel Satis running away as, initially, it will be sold only as an automatic, and firing up or shutting down the engine will require the gearlever to be left in Park.


    No danger of it running away? Sounds like a rather Titanic claim. Here's the other kicker:

    The technology arsenal runs to adaptive cruise control, rain-sensing wipers, automatic headlamp illumination, a tyre-pressure monitoring system, ESP (Electronic Stability Programme), brake assist, a fuel cap integrated into the filler's lid and more airbags than you'd ever want to see deployed during a single crash. All this kit, Renault hopes, will encourage supreme peace of mind for driver and passenger alike


    So we've got an electronic transmission, no manual shutdown, an electronic emergency brake, an "adaptive" cruise control system, and "assisted" electronic brakes.

    All the naysayers may want to check their normal assumptions about cars at the door. This one is French.
  • by Mongo222 ( 612547 ) on Tuesday October 05, 2004 @01:15PM (#10441459)
    Not true. There isn't a car made whose breaking force isn't multiple times as powerful as the power it engine can produce.
  • by Above ( 100351 ) on Tuesday October 05, 2004 @01:18PM (#10441507)
    I don't think a car of that class has a drive by wire system at least not yet. Back when people were driving their Jeeps through walls left and right, due to the pedals being offset more than most cars, Jeep made a video for the court case.

    They showed that in a Jeep, with a large V8 engine, the engine could not at full throttle overcome the brake. Be it from a stop, or while moving. Their catch phrase, "Brakes always win".

    So, as long as the car had a mechanical brake system which was still working he could have stopped.
  • by khrtt ( 701691 ) on Tuesday October 05, 2004 @01:22PM (#10441567)
    My VW used to do that -- the accelerator pedal got stuck sometimes, and I'd have to get under the hood and bang on some pulley to get it to release. My mechanic couldn't figure out what the problem was, so I drove it like that for a year or so. The pedal didn't get stuck every time, only sometimes, and only in really bad weather:-)

    What happenes when you turn off the ignition, and I speak from experience, is:

    1. You loose power steering. Unless your car is fly-by-wire... sorry, drive-by-wire... whatever, I think Volvo made one experimental model like that, but most normal cars retain manual steering even with he ignition off. Incidentally, the darn VW had no power steering to start with, so I didn't have to worry about loosing steering assist. Anyways, power steering is really only useful when you are parking. At speed, steering assist makes very little difference.

    2. You have one brake assist charge in the vacuum accumulator. That is, you can apply the brakes once, normally. The next time you brake you have no brake assist, and you have to really lean on the brake pedal hard. Thankfully, I'm a big guy, so that wasn't a problem.

    3. Steering wheel LOCKS UP. This is a theft prevention device that almost all cars have. Once you take the key out, the steering wheel would lock in a turned position. It would not lock up if the wheels are facing straight, only if you turn. The locking device is rather flimsy, and car thiefs would often brake it by yanking on the wheel real hard. Unfortunately, at speed this is not an option.

    So, here's the algorithm:

    1. Your gas pedal gets stuck.

    2. You make sure the wheels are facing straight to prevent steering from locking up.

    3. You turn off the ignition, put the car in neutral, and turn the ignition back on. The car is in neutral, so the engine won't re-start, but the ignition key is in "Run" position, so the steering won't lock up either.

    4. You hit the emergency flashers, lean on the horn, and pull off. Nicely done. Don't forget that your brakes require a lot more control input then normal.

    Now, I've done the above procedure, what, 20 or 30 times. It's fun, especially if you have a nervous passenger in the car, who gets scared out of their pants:-). Though the most I got a passenger scared was when I forgot to unlock the glove box before driving, and his lighter was in there. The glovebox in the VW, like most cars, locks with the same ignition key. I pulled the key out, unlocked the glove box, and restarted the engine, and gave the lighter to my friend, all while going 90 mph. Nothing dangerous, considering that the road was really straight, so I didn't even make a face, or even think it was gong to be scary. My friend, however, who wasn't used to this as much as I was, crapped his pants. Pardon my French.

    Another option is to simply put the car in neutral. Any manual gearbox allows that, and most automatics would shift to neutral under power too. The engine starts racing, and quickly hits the max RPM stop, but you don't risk getting your steering wheel locked up:-). I would always turn the ignition off, though, since I didn't know if the stupid VW had a max RPM stop, and I didn't care to test it:-).

    DISCLAIMER: If you do something stupid and get hurt, it's own damn fault, and don't blame me. Just because it worked for me doesn't mean it won't kill you.
  • by boa13 ( 548222 ) on Tuesday October 05, 2004 @01:28PM (#10441664) Homepage Journal
    This article (in French) has much more information than what we've had until now: http://www.rtl.fr/rtlinfo/article.asp?dicid=225812 [www.rtl.fr]

    Key points translated from the article:

    * The driver has tried to use the brakes, but he says they quickly heated up and became ineffective.

    * The driver has tried to remove the ignition "key" several times, initially without success.

    * Out of ideas and quite afraid, he has called the police, and has soon been escorted by police motorcycles.

    * The toll booth had been evacuated and left wide open by the police, all vehicles on the highway (around the toll booth) had been stopped and parked on the emergency lane. Even then, entering the booth at 120 mph would have been quite deadly.

    * Fortunately, the driver has stopped the car 12 or 20 miles before the toll booth, by finally managing to remove the smart card that is used as an ignition key on these cars.

    * Renault says there are three independant ways the cruise control system can be deactivated: using the brakes; pressing the appropriate button on the steering wheel; switching to neutral gear. The first two are electronic controls, the last one is mechanical.

    * Renault says the three systems are fully independant, and it is unlikely they all should fail at the same time. Renault says the car will be brought back to its factories as soon as possible, for inspection.

    * The driver was only planning to drive home, a few miles trip, but ended up more than one hundred miles from its planned destination.

    In my opinion, he could have stopped the car much earlier, but was panicked. To those who say he should have had no problem removing the smart card, try doing that while controlling a car at 120 mph on a non-empty highway (at one point, he had to overtake a truck by driving on the emergency lane!).

    As for the failure, there may be three independant systems, but ultimately, there's only one engine, which can go mechanically wrong.
  • by Anonymous Coward on Tuesday October 05, 2004 @01:30PM (#10441701)
    Does anybody here want to compute how steep the hill needs to be to get the Saturn going 105mph? I've tried going downhill in Civics with the clutch disengaged, and couldn't even get up to 80. I seriously doubt that a Saturn has enough mass or aerodynamic efficiency to even have a terminal velocity of 105mph.

    Of course, when the Saturn driver found himself going back uphill with no power steering or brakes, he would just have to engage the clutch to start the engine back up instantly. Since he doesn't need ignition to get the engine running, it wouldn't even matter if the stupid Saturn didn't give him any gas.

    This story smells like the Audi, and the Renault story doesn't smell too good either.

    aQazaQa
  • Comment removed (Score:5, Interesting)

    by account_deleted ( 4530225 ) on Tuesday October 05, 2004 @01:40PM (#10441830)
    Comment removed based on user account deletion
  • by anglete ( 782289 ) on Tuesday October 05, 2004 @01:50PM (#10441960)
    The whole point of this excersize in not giving the engine fuel is to keep it from letting the car go faster than 105mph. That doesn't mean the engine stops spinning. Only when the engine stops spinning do you loose power brakes and steering. This smells of BS. Going down a hill at 105 in gear (auto or manual) means you have full power to all these functions unless something is incredibly wrong or the guy shifted to neutral. I would also doubt that saturn designed the engine control systems to stall if you put it in neutral at 105mph.
  • This happend to me! (Score:2, Interesting)

    by JBoelke ( 523928 ) on Tuesday October 05, 2004 @02:26PM (#10442526)
    This happen to my brother and I driving a manual tramission Saab 900 (this was 1986 or 87). When my brother depressed the clutch, the engine red lined and stalled at 95 mph. This was befor cell phones so we did not have the police clear the way. We coasted to the side of the road and determined that the mechanic did not properly reistall the cruise control after doing other mechinal work. (The crusie control was on top of the engine) After about 1/2 an hour the pressure in the engine adjusted it self and we were able to continue driving. This time without the cruise control.
  • 1971 Datsun Pickup (Score:4, Interesting)

    by peacefinder ( 469349 ) * <(moc.liamg) (ta) (ttiwed.nala)> on Tuesday October 05, 2004 @02:42PM (#10442716) Journal
    Same thing happened to me once. But I wasn't in France at the time.

    I was driving my dad's red 1971 Datsun pickup on my way to work. (My brother had rolled it a couple times, but it was a Datsun so of course it still ran as good as ever.) A light ahead changed to yellow, and, being about 20 years old at the time, I did what came naturally: I floored it.

    Not that flooring a '71 Datsun 1600cc engine had much of an immediate effect. But I did start accellerating, and I made it through the light whilst it was still yellow. Sweeeet. I let off the gas.

    The engine continued to rev up.

    "Oh, shit," said I. I was up to about 50MPH (in a 45 zone) and accelerating. The next light was about 400 yards away and red, with cars backed up waiting in every lane going my way. It was familiar territory, so I knew the light wouldn't be green before I got there.

    I started to panic. I dropped the clutch, and the engine started to wind up. I had no tachometer, but I knew that sucker was gonna tear itself apart if I let it go on like that. I shoved into high gear (4, no overdrive) and engaged the clutch again. Naturally this was a slightly wrenching experience; the RPMs dropped and the vehicle lurched towards the firey doom ahead. In full panic now, I dropped the clutch again with the same result as before. I re-engaged the clutch.

    I thought "I am going to die in about ten seconds. Nine. Eight. Oh yeah, the switch."

    I turned the engine off and pulled over. Heh. Silly me.

    Turns out that the throttle pedal itself was jammed. There was a little mushroom-shaped backstop attached to the firewall, and when I had floored it I had shoved the perdal sideways a bit, and gotten it stuck behind the backstop.

    The moral of the story? Panic is not helpful, even the simplest devices can fail, and every powered device needs a kill switch.
  • by bmajik ( 96670 ) <matt@mattevans.org> on Tuesday October 05, 2004 @03:15PM (#10443136) Homepage Journal
    I drive, amonst other things, a 1988 BMW M5.

    This car has mechanical power steering and mechanical power brake assist. however, it is incorrect to say that power brakes are just a vacuum booster. Many are, but many are not, especially mid 80s german cars that didn't really draw enough vacuum for a vacuum based brake assist. (Some BMW, Audi, and VW models feature non vacuum assist)

    Those vehicles have a hydraulic brake booster which is run as a separate output channel from the power steering pump. The power steering pump cant react fast enough for panic threshhold braking, so such cars have a brake pressure accumulator or "brake bomb" which stores pressurized power steering fluid. This pressurized fluid is what provides brake force assistance. Note that the power steering fluid and brake fluid are separate and do not mix; it's just that the brake power regulator uses stored pressure from the PS system to pressurize the brake system.

    I recently replaced the brake pressure accumulator on my BMW.

    Now, ancient brake technology dissertation aside - i have _very_ relevant experience regarding loss of steering and braking power.

    I was on Brainerd International Raceway in Minnesota with my M5. This racetrack has a 1 mile long front straight, and turn 1 is banked. I was entering turn 1 at about 125mph (its a 4 door sedan, give me some slack) and midway through the turn i felt my steering get a bit "funny". I immediately recognized the loss of power steering. KNowing what i know about the car, i checked the brake pedal and found i had no power braking either.

    Turn 2 can also be taken in excess of 100mph in my vehicle, but turn 3 is a 110 deegree turn that can't really be navigated above 50mph in a sedan on street tires. So I had no power steering and no power brakes, and i had to slow down 4000 lbs of vehicle, driver, and passenger from in excess of 100mph to about 40 mph.

    This was no problem, honestly. You can do the entire back section of BIR without braking once you get past turn 3 if you're running a cool down lap. I really stood on the mechanical unassisted brakes to get speed down by turn 3, and then i was able to drive the car back into the pits.

    The problem? The power steering pump is belt driven, and since the power steering pump also pressurizes the power brake system as described above, when the belt snapped, i lost power steering and power braking. My brake presure accumulator, which normally stores enough pressurized fuild to perform 3-4 full brake applications even in the total loss of engine power and brake assist, was faulty (thats why i replaced it a few weeks later :) so thats why i had no power braking as soon as the belt went.

    So, the moral of the story is
    1) knowing how your car works is helpful. I got a ride over to NAPA, bought a new belt, and was back on the track for the next session. I remained calm even though i had the most difficult braking maneuver on the track coming up in less than 15 seconds.

    2) The key to all driving situations is operator skillset and awareness.

    Here's another short story:
    Once in my 1980 BMW 528i i was cruising along the highway, with cruise control enabled. This was an aftermarket cruise control system, as it did not come on this specific vehicle from the factory. I opted to take an off ramp (which went up hill, as they often do in the midwest) and when i dipped the clutch the engine started bouncing off the rev limiter. Manually cancelling the cruise control had no effect. This took me quite by surprise so i killed the engine and slowed to a stop on manual brakes.

    The cruise control cable had stuck. OPening the hood, wiggling the cable returned the throttle to the closed position.

    Note that at BMW Club track events, a specific part of the technical inspection is the condition and function of the throttle return spring. Driving at speed requires nuance in the use of the throttle, a stock throttle can be a real problem.

  • by swschrad ( 312009 ) on Tuesday October 05, 2004 @03:35PM (#10443341) Homepage Journal
    every one. a button that stops the current operations and goes back to stasis. in the case of a car, no forward energy would seem to be the logical application. in the case of OS, the only one I've ever seen that would almost always stop a current operation (like a SQL search on the null set) was NeXTStep, ctrl-period IIRC.

    have you written one in lately?
  • Get back to basics. (Score:2, Interesting)

    by stimpleton ( 732392 ) on Tuesday October 05, 2004 @04:20PM (#10443926)
    Granted, this is all very high tech but stuck throttles have occurred for decades with just as dramatic consequences.
    Its called a frayed throttle cable. Interestingly, "driver intervention" is surprisingly low, with drivers stopping only when they run into something.

    Other causes that I have seen(I was a mechanic for 15 years before I got involved with the computer side of things:

    - "Damper pots" on carburetors work fine controlling the secondry throttle plate, till a rubber o-ring perishes within the carb, and engine vacuum sucks the rubber diaphragm in the pot fully home and the throttle opens fully.
    - Piston type accuators that wear, and the piston finally tilts and sticks...at the last speed you were going.
    - In some EFI cars, when a vacuum seal of gives way, the lean mixture can be aggresively compensated by the EFI unit, resulting in at least partial throttle.

    Some (but a fraction) of vehicles formally identified w/ throttle probs that have resulted in similar results as the article:
    - 2001 Ford escape - Water enter servo, throttle sticks.
    - Nearly all european cars to 1982 - Poor corrsion ressistance, cable sticks against the outer cable.
    -1990 Ranger - Throttle cam wears and sticks against air intake tube, where there was only 1 mm clearance at new.
    - Oldsmobile Toronado/Trofero - worn nylon bush. Throttle sticks wide open.
    - 1996 Honda Accord/Accura - Carpet by throttle pedal snags pedal, preventing its return.
  • by steve_l ( 109732 ) on Tuesday October 05, 2004 @04:59PM (#10444384) Homepage
    I had a renault megane for rental in the Alps in may.

    Their fancy rfid tag ignition key is cute; just plug it in and hit the go button. There is no stop button; you just come to a halt then pull the card.

    The moment you pull the card it actually puts the handbrake on. The handbrake comes off when you restart the car, put it in gear and rev the engine.

    I didnt have a 125mph chase down the autoroute, but we did have a scary time doing a 3 point turn on an alpine pass in the snow. The road was closed and we had to turn round. But you cannot spin up the engine and clutch then gently come off the handbrake, as you normally do on hill turns. As soon as you hit the accelerator your brakes would come off. So the only safe way to hill starts is to make 100% sure you are in the right gear (ie forwards and not backwards), then hit the accelerator hard. Get it wrong and you drive off the mountain at speed.

    I think the Renault line have added a bit too much automation these days. I note the German toys havent gone that far yet -not even Mercedes- and I think they knew what they were doing.
  • Kill switch (Score:3, Interesting)

    by Krellan ( 107440 ) <krellan@kr e l l a n .com> on Tuesday October 05, 2004 @05:52PM (#10445031) Homepage Journal
    Lessons learned:

    1) Any vehicle with an ignition system that can't be turned off the same way it was turned on -- from Renault's new smartcard ignition system, to an old-style lawnmower with a pull cord -- needs a KILL SWITCH! Pressing the kill switch shuts off the flow of gas/spark/whatever to the engine, causing it to stall, and would not have any other side effects such as re-engaging the steering column lock.

    2) Pedals usually have different shapes: a horizontal rectangle for the brake (or clutch), and a vertical rectangle for the throttle. These are shaped differently on purpose: when strongly pushed, you should feel the difference in your feet as your shoes bend around the pedals differently! Often, the pedals will even be at different heights: notice the gas pedal is lower than the brake, on most cars.

    3) Say what you will about our overzealous product safety/testing/defect laws, but there's a reason Renault cars aren't sold anymore in the US :)
  • by agallagh42 ( 301559 ) on Tuesday October 05, 2004 @11:06PM (#10447241) Homepage
    "This is exactly what gasoline-electric hybrids like the Civic Hybrid and the Prius rely on when they shut off their engines."

    Actually, no. The Prius and Civic Hybrid both use electric assist for their power steering and braking systems.

    The steering is a simple electric motor that assists with steering force, and the brakes have an electric vacuum pump to maintain vacuum in the system.

    The Prius actually uses a "brake-by-wire" system (with hydraulic backup), so the computer controls the braking pressure that gets applied. It does this because the regenerative braking system causes the brakes to be twitchy, so the computer has to make adjustments to smooth it out.

An Ada exception is when a routine gets in trouble and says 'Beam me up, Scotty'.

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