The Toyota Witch Hunt • Hacker News Board

Re: The Toyota Witch Hunt

#91

Post by philwelch » Sat, Mar 06, 2010, 6:46 AM UTC

stcredzero wrote: post #47

If Congress really wanted to get at the truth, they should have called disinterested third-party engineers to study and get their opinion on this case. Nobody believes Toyota, even if the final facts prove it's correct. Everyone believes the witnesses, even when the engineering evidence often disproves their testimony. It is impossible to come to a scientifically valid conclusion under those two circumstances, which…

"the LCD American voter..."

Heh, that works on two levels--not just "lowest common denominator" but also the American voter who watches too much TV news on their LCD HDTV.

Re: The Toyota Witch Hunt

#92

Post by dwwoelfel » Sat, Mar 06, 2010, 7:08 AM UTC

ryoshu wrote: post #77

zzzmarcus wrote: post #25

Can someone explain to me why Congress gets involved in investigating things like Toyota's manufacturing defects or the way college football teams are ranked? Does Congress have a legal mandate to investigate anything it deems to be interesting/fishy/a potential target for legislation? Has Congress always conducted these types of investigations or is it a modern phenomenon?

Any company that deals in interstate commerce -- or international commerce -- falls under the purview of Congress. Article I, Section 8, Clause 3

Are we really downvoting facts now? I assume that the people who are downvoting don't think that the commerce clause should be used to grant congress such wide powers. I agree, but you can't just downvote the situation. You have to recognize the problem before you can fix it. So thanks, ryoshu, for reminding me of the part of the constitution that needs to be amended.

Re: The Toyota Witch Hunt

#93

Post by cookiecaper » Sat, Mar 06, 2010, 8:19 AM UTC

electromagnetic wrote: post #85

evgen wrote: post #57

Earlier quoted context omitted.

While it is easy to say "put it in neutral", this is not quite a simple as it once was. With the popular serpentine shift patterns on modern cars a lot of people are surprised to find that neutral is no longer just a spot on the transition path between park and drive. To take a frequently cited example, the ES350 whose stuck accelerator killed a CHP officer and his family has a shift pattern that makes getting into n…

Putting into neutral isn't a necessity, any downshift in gears will increase the torque of the engine and thus decrease the maximum velocity. Even if you can't get it into neutral, getting it into 1st or 2nd will still get you slowed down to a more manageable speed. The major failure of all automobile manufacturers is that they haven't implemented a fail safe mechanism in the event of engine failure at velocity. If t…

I think it's probably because people would assume that a car with a big button that says EMERGENCY STOP or something like that is more likely to need an emergency stop button than a car that doesn't have one.

Though I guess they already have that in the form of "emergency brake". Do you suggest they implement electronics to perform these functions when the e-brake is depressed?

Re: The Toyota Witch Hunt

#94

Post by phaedrus » Sat, Mar 06, 2010, 8:26 AM UTC

jellicle wrote: post #63

"As noted before, brakes always win out over engines, even at full throttle; that has been tested and proved many times in the past 20 years, including recent Car and Driver tests on Toyotas." This is not necessarily true. It's entirely dependent on the brakes involved and the engine involved; any given vehicle could go either way. I personally have witnessed steel brake rotors melted and dripping off the vehicle; th…

Absolutely. I used to own a V-8 Ford pickup; if you happened to hit the brakes and the gas at the same time the power of the engine would completely overwhelm the brakes and the truck would (start to or continue to) move. If you accidently left the parking brake on, you couldn't discern a difference while driving it. Coming from a state where many people own pickup trucks, I was taught that the engine will overpower the brakes, every time. Now I own a small car with exceptional brakes that I'm sure would stop in that situation, but that's just the exception that proves the rule - it depends on how big your engine is.

Re: The Toyota Witch Hunt

#95

Post by phaedrus » Sat, Mar 06, 2010, 8:30 AM UTC

sliverstorm wrote: post #72

By the way, just in case it ever helps anyone: If you are in a car moving along and you have to kill the engine, or the engine dies, get on the brakes as fast as you can and don't let go. You can ease up on the brakes almost to the point of letting go of the pedal, but don't come off all the way. The reason is the brakes will maintain the power-assist vacuum from the engine, even when the engine is later switched off…

I can't see why that would be necessary.

The vacuum assist is just that - an assist. The brakes still work if you don't have it, you just have to put some extra force on the pedal. It isn't even that much force; I've driven older vehicles that don't have any assist at all and it's not that much harder to push the pedal.

Re: The Toyota Witch Hunt

#96

Post by mistermann » Sat, Mar 06, 2010, 8:58 AM UTC

I believe two things related to this:

1. to a certain degree, the US is punishing Japan due to their recent actions in the bond markets. This is a very important problem for a very small amount of people, but it makes great headlines. Do you think the US government is genuinely interested in resolving this properly from an engineering perspective?

2. that 100% "drive by wire" systems should not be allowed...there should be a big red "holy shit" kill switch on the dash of modern cars that kills power to everything except steering and brakes

So, imho, its a very serious problem, that affects very few people (in the big scheme of things), and there is a very simple solution, for going forward technology at least, if not existing models. But do you guys get the feeling that this is what the conversation is actually about? Something seems a bit odd to me.

But then I'm one of those conspiracy theorists that think when you're running 15% budget deficits and have real (as measured using historical methods) unemployment of 20%, and many bond issues are taken down 50% by the federal reserve (literally printing money to buy your own debt), that you will start to observe unusual things happening in the marketplace. The adherents of Occam's Razor would imply that that I am simply crazy, becasue the simplest answer is always the correct answer. So I guess thats it.

Re: The Toyota Witch Hunt

#97

Post by Confusion » Sat, Mar 06, 2010, 11:13 AM UTC

presidentender wrote: post #12

erlanger wrote: post #8

I hold the conspiracy theory that these issues are being so aggressively sought out in an attempt to bring Toyota's image down to the level of American auto manufacturers.

I wholeheartedly agree. The sheer number of failures that have to occur, the low level of action on the drivers' parts required to overcome the problem (put it in neutral! Use your brakes! Use your parking brakes!), the speed and intensity of the government's response, and the fact that GM is so unpopular combine to make the entire debacle suspect.

Not to mention the curious fact that these incidents only happen in the US, even though there are vast numbers of Toyota's out here in Europe.

Re: The Toyota Witch Hunt

#98

Post by Confusion » Sat, Mar 06, 2010, 11:23 AM UTC

jonknee wrote: post #28

cryptnoob wrote: post #19

Earlier quoted context omitted.

Please forward your proof of this to Toyota and the congressional committee to which Toyota swore this was not the case. It's tempting to blame drive by wire, since electronics is black magic to most people. Keep in mind that most passenger jets in the sky are fly by wire, these days. For you to point blank claim this to be true, when it's been flatly denied several times, seems a bit over the top, don't you think?

Complaints of out of control acceleration increased several times over after moving to DbW and some recent complaints have noted that no floor mats were in the vehicle (which makes it hard to blame on floor mats): http://articles.latimes.com/2009/nov/29/business/la-fi-toyot... Toyota is claiming it's not the DbW system, but they also thought they had this issue fixed a long time ago. It's a hard thing to prove unless…

Complaints of out of control acceleration increased several times over after moving to DbW

Complaints of out of control acceleration increased after 2000. I guess it's the millennium bug. In other words: correlation is not causation. Moreover, no numbers are presented to actually support this correlation. What about 1996-1999? 100 cases would be totally plausible.

Even Woz thinks is the DbW software With the rather important difference that it doesn't actually cause any problems, because he can just brake and make the acceleration stop.

Re: The Toyota Witch Hunt

#99

Post by snom370 » Sat, Mar 06, 2010, 11:58 AM UTC

cryptnoob wrote: post #29

jonknee wrote: post #18

Earlier quoted context omitted.

> The accelerator pedal would have to be immovable, frozen in place. In recent Toyota vehicles the pedal isn't connected to the throttle--it's drive by wire. In theory the computer could continue accelerating regardless of the gas pedal's position.

I've designed systems like this. You use redundant potentiometers to sense throttle position. If they don't match within 5%, you power down. You also toggle bits in your code. One in the main loop, another in any interrupt service routine that you are dependent upon. These bits then go to a GPIO so that the GPIO toggles. If the ISR freezes or the main loop freezes, the GPIO quits toggling. You then have an hardware,…

Still, this doesn't account for the case where the CPU and the watchdog signal is working, but the algorithm isn't. Pure software malfunctions, have happened on commercial airliners, where there are quite stringent FAA requirements regarding how the software is developed and maintained. So it wouldn't be surprising if it happens in automotive systems, where you might not have the redundancy of multiple CPUs running concurrently.

I'm not sure if automotive systems are held to any certification standards. Maybe someone working in this field could answer that?

Re: The Toyota Witch Hunt

#100

Post by [deleted] » Sat, Mar 06, 2010, 1:20 PM UTC

jsz0 wrote: post #83

erlanger wrote: post #8

I hold the conspiracy theory that these issues are being so aggressively sought out in an attempt to bring Toyota's image down to the level of American auto manufacturers.

I don't buy that. The US has a big interest in the Japanese economy that goes well beyond the auto industry. I think it's just media fear mongering. If you do own a Toyota it's hard to ignore so they're going to milk it for every cent it's worth.

[deleted]