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Toyota Unintended Acceleration and the Big Bowl of “Spaghetti” Code (2013)

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Re: Toyota Unintended Acceleration and the Big Bowl of “Spaghetti” Code (2013)

#41

Post by radiorental »

delinka wrote: post #39
Jansemon wrote: post #37

How can breaks not stop the engine?! Parking break being a different thing, but the main ones?

"Brakes" are at the wheels. The only time stopping a car from rolling also affects the engine is when everything remains engaged (manual transmission, manual clutch; in gear, clutch not depressed to the floor.) In a vehicle with an automatic transmission, the transmission begins to disengage from the wheels as the wheels spin slower than the engine is pushing. (Very simplified explanation...) i.e. brakes on cars are…

Also, it's been reported that drivers pumped the brakes in a panic (and understandably so).

This will have the effect of reducing the power assist, which is already reduced due to high revs / low vacuum.

Re: Toyota Unintended Acceleration and the Big Bowl of “Spaghetti” Code (2013)

#42

Post by Jemmeh »

quant5 wrote: post #8

Patio11 has talked about how programmers are little respected and paid poorly in Japan compared with the US. Could this have something to do with Toyota's code quality being so poor and causing this issue?

That seems so strange to me since I always think of Japan as being so technologically advanced.

Granted, even here in the USA programming used to be considered "women's work", mostly revolving around planning and organization. So they passed it off to secretaries. I just didn't think that was something that was still happening.

http://www.smithsonianmag.com/smart-news/computer-programmin...

Re: Toyota Unintended Acceleration and the Big Bowl of “Spaghetti” Code (2013)

#43

Post by Jtsummers »

hoorayimhelping wrote: post #25
swiley wrote: post #2

Critical systems should be open source by law.

I love magic bullets! As we've recently seen with things like Heartbleed, open source has no vulnerabilities, no bugs, no errors, and is free from all the problems of proprietary software.

One of the problems with embedded systems like this is that very few eyes ever see the code. Even in more regulated fields like avionics. The code will be examined primarily by the developers, testers, their QA and maybe the company that hired them if it's contracted out.

Instead, what gets examined are the artifacts like requirements documents, the results of tests, specifications and such. This allows poor code quality to be hidden, and, to some extent, encourages sloppy development practices (especially when time is critical). Exposing the code to more people will have several effects, but the main two (from my perspective) are:

* Developers won't release as much bad code, either due to pride or insistence from their management.

* Bugs may be more easily discovered and diagnosed if the code is available. As it is now, it's a black box. So if I find an issue I may be able to repeat it, but I can't examine the code to see why it's actually happening or to correct it.

Re: Toyota Unintended Acceleration and the Big Bowl of “Spaghetti” Code (2013)

#44

Post by nkrisc »

hoorayimhelping wrote: post #25
swiley wrote: post #2

Critical systems should be open source by law.

I love magic bullets! As we've recently seen with things like Heartbleed, open source has no vulnerabilities, no bugs, no errors, and is free from all the problems of proprietary software.

And then it was discovered and fixed.

Re: Toyota Unintended Acceleration and the Big Bowl of “Spaghetti” Code (2013)

#45

Post by oldpond »

I am quite surprised by this, especially since it comes from Toyota, the company that invented Lean. This is very relevant given that the debate over upgrading vehicle software is raging on and the Volkswagen scandal has not settled just yet. Too bad we can't crowd source the various automobile software development teams. I am curious to see if any of them are any good. In my travels over the last 10 years I have encountered very few skilled software development teams at the enterprise level. Given the current state of the industry I would not e surprised to find them all wanting.

Thanks for posting.

Re: Toyota Unintended Acceleration and the Big Bowl of “Spaghetti” Code (2013)

#46

Post by dmschulman »

benihana wrote: post #27
TerraHertz wrote: post #3

I'm a retired electronics design engineer and embedded programmer, and I will NEVER own a car with any kind of vehicle/engine management computer. Old cars for me, forever. I flatly refuse anything but fully manual and direct mechanical gears, clutch, steering, brakes and throttle. Curiously the chief engineer I knew at a major car service center, also felt the same way. And that's not even touching on the insanity o…

I love the absurdity of this and arbitrariness. You'll happily drive in a car, one of the most dangerous machines people use regularly. But if it has a computer in it, no siree, that's when things get too deadly to deal with. All of the other thousands of moving parts, like the thing that takes energy-dense hydrocarbons and ignites them several thousand times a second in hot, high pressure tubes - that's fine and tot…

You could easily extrapolate this argument to the Internet of Things if you need a way to understand the poster's point differently. Do you want or even really need a toaster with a computer in it? A refrigerator with a computer in it?

Analog toaster and refrigerator technology has been working quite well for us for almost a century.

Re: Toyota Unintended Acceleration and the Big Bowl of “Spaghetti” Code (2013)

#47

Post by UnoriginalGuy »

ebbv wrote: post #34
stretchwithme wrote: post #9

These unintended acceleration incidents seem to happen mostly to elderly drivers. http://www.theatlantic.com/business/archive/2010/03/how-real...

And more importantly than that there are a couple of underlying facts that invalidate the whole premise that unintended acceleration means automatic accidents/death: 1) None of these cars are 700hp Supras that accelerate at drastic speeds. These were normal consumer cars that frankly aren't that fast even with the throttle fully depressed. 2) The brakes in all of these vehicles are many times more powerful than the e…

Your two point list is silly. Consumer cars & SUVs can go 0-60 in under 10 seconds in almost all cases, and the fact that the brake can overcome that acceleration is great, except it takes time, and within the time between unexpected acceleration and stopping damage/injuries/death can occur.

I had a water bottle fall onto my right leg while turning, this caused a sudden but short lived acceleration (e.g. 10 MpH of unexpected acceleration for less than 1 second), this was enough to cause me to mount the curb, and do some decent property/car damage (thank god nobody was on the curb). The brakes worked perfectly, and stopped the car, but it does show how much damage even a tiny burst of unexpected acceleration can do (the entire incident was under 5-10 seconds).

It honestly boggles my mind that someone can dismiss any length of unexpected acceleration because "cars [aren't] 700 hp Supras." Consumer cars are plenty powerful enough to cause injury and death due to any length (even 1 second) of unexpected acceleration at the wrong moment. Sure, if you're going straight on the freeway then you aren't going to even notice, but in a car park, while turning, or stopped at a school crossing, the brake's ability to overcome the engine are largely irrelevant since you won't be expecting it.

Re: Toyota Unintended Acceleration and the Big Bowl of “Spaghetti” Code (2013)

#48

Post by illumen »

It's interesting that VW cars have been taken off the road for unintended acceleration. Also that quickcheck was used to find many timing related bugs between software components that VW uses. It was used after the models were taken off the road. There are other models still not recalled using similar software from the same era.

Re: Toyota Unintended Acceleration and the Big Bowl of “Spaghetti” Code (2013)

#49

Post by alistairSH »

UnoriginalGuy wrote: post #47
ebbv wrote: post #34

Earlier quoted context omitted.

And more importantly than that there are a couple of underlying facts that invalidate the whole premise that unintended acceleration means automatic accidents/death: 1) None of these cars are 700hp Supras that accelerate at drastic speeds. These were normal consumer cars that frankly aren't that fast even with the throttle fully depressed. 2) The brakes in all of these vehicles are many times more powerful than the e…

Your two point list is silly. Consumer cars & SUVs can go 0-60 in under 10 seconds in almost all cases, and the fact that the brake can overcome that acceleration is great, except it takes time, and within the time between unexpected acceleration and stopping damage/injuries/death can occur. I had a water bottle fall onto my right leg while turning, this caused a sudden but short lived acceleration (e.g. 10 MpH of un…

Agreed.

Modern cars, even the modest ones, are fast enough that they can get out of control very quickly. While the brakes certainly can slow a vehicle with its throttle stuck open, the real question is what impact does that stuck throttle have on the average driver? When the brake doesn't work as expected, does the average driver continue to brake? Do they pump the brake pedal? Something else altogether? How long does it take them to regain composure and act sensibly (in this case, putting the car in neutral while continuing to brake aggressively)? If that slowed reaction is more than some fraction of a second, accidents will happen.

Re: Toyota Unintended Acceleration and the Big Bowl of “Spaghetti” Code (2013)

#50

Post by feintruled »

TerraHertz wrote: post #6
luckystarr wrote: post #5

Earlier quoted context omitted.

Agree. What about power steering? You won't get any car without nowadays. Do you count non-computerized (servo) power-steering as "mechanical steering"?

I don't think you'd be able to get any new non-computerized car at all today. Emission control makes computerization an absolute requirement. That's why choice in cars for people who feel the way I do is limited to old cars from pre-90s. Suits me fine. Servo power steering is acceptable, though my present car (1993 Subaru stationwaggon) has direct steering, and I prefer that.

Car manufacturers have made giant leaps in driver safety though (going by NCAP star ratings and the like). Drivers can now walk away from what once would have been a fatal crash - are you comfortable forgoing all those advancements?
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