Recent Engineering Debacles 7

[hidalgoe]

HellO:

What have been the results of recent engineering debacles, like Boston's Big Dig concrete section that fell and killed some folks in a car or Katrina meant for PE's as far as liability and ethics are concerned?

 

[btrueblood]

Mac,

I think the original Audi article was somewhat poking fun about the idea, but it implied that it had been seriously debated by Audi at some point.

Does the software on a by-wire throttle system not detect if the brake is depressed, and reduce/eliminate the throttle input if that is the case? Shouldn't it (power-braking hotrodders need not reply)?

 

[brandoncdg]

DanDel: Maybe the company thought they had a high chance of losing so they settled. The more I read about who gets sued for what in this Country scares me to know end as a business owner.

macgyvers2000: I thought I recognized your signature from the s2ki forums.

Civil Development Group, LLC
Los Angeles Civil Engineering specializing in Hillside Grading

http://civildevelopmentgroup.com

http://civildevelopmentgroup.com/blog

 

[MacGyverS2000]

brandon, what's your handle?



Dandel, If memory serves, I believe the recommended the correct epoxy during the planning stages, but shipped out the incorrect epoxy months later when design changes were in play (I think the person responsible for filling the order did not comprehend the changes that were being planned). but it has been a while since I looked at the docs...

Dan - Owner

http://www.Hi-TecDesigns.com

 

[drawoh]

Did not Audi suffer similar problems about 15-20 years ago? I recall reading that the problem then was that they hadn't accounted for the fat feet of affluent American women buying their cars, or some such.

They hit the wrong pedal. P.J.O'Rourke wrote this up in Parliament of Whores.

I have a book at home which I will have to look up. I can't remember the title at the moment. They described an accident in which a cop hopped into a police van, and it took off screaming and ran a couple of people over. There was an interlock that prevented the driver from shifting out of park without pressing the break. Eventually, it was discovered that the police lights on top of the van, disabled it.

I think that the real failure is that people hop into automatic transmission cars and hit the gearshift and brake all in one motion. This is especially dangerous if you are twisted around in your seat, looking out the back window.

If you sit squarely in the driver's seat and place your foot on the brake, you will have time to calmly figure out why the engine is roaring and screaming.

JHG

 

[hokie66]

DanDel,

There were a total of 15 defendants in the Big Dig lawsuit filed by the family of the lady who was killed. Total of $28 million. The attached article reports that $10 million of this was in early settlements by the fastener suppliers.

http://www.usatoday.com/news/nation/2008-09-30-big-dig-death_N.htm

 

[hokie66]

And this was the settlement of the state's lawsuit.

http://www.foxnews.com/story/0,2933,324985,00.html

 

[unclesyd]

Pure supposition on my part, the product of warped mind.

I've talked to two people who have had acceleration problems and the only common thread was in every incidence (8) they were talking or texting using the same brand of cell phone. Wouldn't it be blivit if a certain transmitted group would cause the computer to call for acceleration. The lawyers are already salivating I don't know if they could take additional euphoria.

 

[GregLocock]

"Does the software on a by-wire throttle system not detect if the brake is depressed, and reduce/eliminate the throttle input if that is the case? Shouldn't it"

I drove 4 different makes of car yesterday. All of them allowed full brake+WOT as a valid control state.

If you don't allow throttle+brake then there are going to be cars abandoned all over the country, as there are circumstances where it makes sense.

Howver I suspect that there will be some sort of longer term outcome, either an explicit 'stop engine' control (such as a key that you can turn), or perhaps smarter software that recognoises panicky braking and that then idles the engine.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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[patprimmer]

I would have thought a steep uphill start requires left foot brake with throttle applied until the engine has sufficient pre-load to prevent roll back when the brake is released. Also as a hot rodder, I won't be quite so easily silenced or dismissed. I like to left foot brake and be first off as the lights turn green.

Regards
Pat
See FAQ731-376 for tips on use of eng-tips by professional engineers &

http://eng-tips.com/market.cfm

for site rules

 

[TDAA]

I would have a hard time left foot braking and working the clutch at the same time. That is why I like the hand break for those hill starts. For an auto trans, I only do that when pulling out of a tight parking spot on a hill.

I agree with Greg, sometime you need to do certain things. It irritates me when there are governors applied too close to speeds you may travel. I think it is dangerous.

 

[patprimmer]

Ummm

If it's a manual transmission there is no problem with the drive by wire as you simply depress the clutch.

To hill start you heel and toe the throttle and brake and of course left foot the clutch.

This thread was pretty much all about automatics I think.

Regards
Pat
See FAQ731-376 for tips on use of eng-tips by professional engineers &

http://eng-tips.com/market.cfm

for site rules

 

[MacGyverS2000]

Pat,

The emergency brake should be used on steep grade hill starts. Engage brake, apply light gas, release brake.

Dan - Owner

http://www.Hi-TecDesigns.com

 

[GregLocock]

Only works on steep clay slopes, with an auto, if you had the non existent 4 wheel park brake. The 4wd training course we do explicitly includes a bit of a track where throttle +footbrake is the only way to get an auto up the slope. The lesson learned is that you'd rather be in a manual. - put it in low, kill the engine, clutch out, release all the brakes, key on.

Seriously, there are many examples for people who actually use their vehicles where you need to combine both controls. It may not be a big deal for city dwellers, that is not the point.





Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

http://eng-tips.com/market.cfm?

 

[patprimmer]

Dan

Only if you don't know how to heel and toe properly.



Regards
Pat
See FAQ731-376 for tips on use of eng-tips by professional engineers &

http://eng-tips.com/market.cfm

for site rules

 

[drawoh]

My reference is Inviting Disaster -- Lessons from the edge of technology by James R. Charles. Google Officer Thomas Sawina.

I have never used the parking brake to start my manual transmission car up a hill.

JHG

 

[moltenmetal]

I had a throttle cable freeze and stick in the full throttle position once- on a manual transmission car. Putting your foot on the clutch is a recipie for major engine damage unless you also shut off the ignition...

 

[patprimmer]

Modern engines have rev limiters.

High speed crashes damage more than engines.

Regards
Pat
See FAQ731-376 for tips on use of eng-tips by professional engineers &

http://eng-tips.com/market.cfm

for site rules

 

[MacGyverS2000]

Pat,

I didn't say that was the method I used, just that it's what the average driver should be doing. In my manual cars on steep hills, I just switch very quickly from brake to gas... I roll a couple of inches, at best.

Dan - Owner

http://www.Hi-TecDesigns.com

 

[unclesyd]

From the Wall Street Journal about 40 minutes ago.

"Toyota has recalled millions of cars over a defect that causes sudden acceleration. The company says it has the fixes in hand, and that dealers can begin making the cars safe, but the U.S. Transportation Department is investigating claims that electromagnetic interference might be causing Toyota electronic throttle systems to malfunction."

 

[btrueblood]

Thanks drawoh, that is exactly where I read it.

"smarter software that recognoises panicky braking and that then idles the engine. "

Ok, that sounds right Greg, and more what I was thinking, even if it didn't come thru my fingers to keyboard. The concept of opposing inputs requiring a fail-safe condition. Better to fail to a car that won't go, than to one that won't stop.