Toyota uncontrolled throttle
Toyota uncontrolled throttle
(OP)
Regarding the Toyota troubles currently in the news; any chance of this being a "drive-by-wire" software (or hardware) issue, as opposed to a strictly mechanical, binding throttle linkage,ect problem?





RE: Toyota uncontrolled throttle
Dan - Owner

http://www.Hi-TecDesigns.com
RE: Toyota uncontrolled throttle
Dan - Owner

http://www.Hi-TecDesigns.com
RE: Toyota uncontrolled throttle
Something that simple would not necessitate the complete shutdown of so many model lines and the suspension of all sales. Something fishy?
Rod
RE: Toyota uncontrolled throttle
They did suspend all sales, as of yesterday, I believe. It affects 8 models, 2009-2010 model years.
Dan - Owner

http://www.Hi-TecDesigns.com
RE: Toyota uncontrolled throttle
They're sending notices for people to bring the cars in and have them retrofitted with a new linkage as an immediate solution. Now, whether or not they also play with the ECU I cannot say.
This is going to be a nightmare for them. Since they have asked people do not continue to drive the car until the repair has been applied, they may have to pay for people to have their cars towed in, and that won't be cheap by any means.
Dan - Owner

http://www.Hi-TecDesigns.com
RE: Toyota uncontrolled throttle
Dan - Owner

http://www.Hi-TecDesigns.com
RE: Toyota uncontrolled throttle
Like I said, very suspicious. Hard to believe they cannot find the problem and it's going to cost in the $billions...
Rod
RE: Toyota uncontrolled throttle
This is distinct from the drive by wire issue, I guess.
What's odd is I see reports of cars that accelerate by themselves, not just refusing to slow down (althoughI'd agree that if you are unnerved they might feel similar).
Cheers
Greg Locock
I rarely exceed 1.79 x 10^12 furlongs per fortnight
RE: Toyota uncontrolled throttle
Rod
RE: Toyota uncontrolled throttle
This is a perfect storm of a problem probably caused by over-engineering (going from mechanical to wire), or lack of redundancy under engineering (like not having 2 pedal sensors and 2 throttle sensors that all have to agree or it fail-safes). It's compounded in some cases by the fact it's not quick and easy to turn the key off. Like in the case of the Lexus with the remote key-fob.
The accidents also illustrate a probable lack of driver education in this country. Like shift into neutral or, full brakes trump full throttle.
RE: Toyota uncontrolled throttle
Regards
Pat
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RE: Toyota uncontrolled throttle
An interesting LA times article from a couple of months ago:
ht
Dan - Owner

http://www.Hi-TecDesigns.com
RE: Toyota uncontrolled throttle
That gave me quite the chuckle this morning. You're absolutely right
RE: Toyota uncontrolled throttle
You can train people to more-or-less follow the rules of the road and to present at least a semblance of obedience to posted signs. I'm much less sure that you can teach presence of mind while under extreme pressure.
Norm
RE: Toyota uncontrolled throttle
The "problem" with the local Toyota that I posted was that not only were all the brakes smoking and the throttle stuck, the trans was stuck in gear...Neutral could not be engaged!
Lucky man. Slow speed problem. Dealer close by. Ok? Well put that scenario into a car at 70+. Even an experienced driver would have problems---Pretty much as the CHP instructor and his family in the Lexus?
Way more to this than is being made public so far. You just do not recall 2.3 million cars, shut down six mfgr facilities in two countries and cease all sales because of a mechanical issue!
Rod
RE: Toyota uncontrolled throttle
Cheers
Greg Locock
I rarely exceed 1.79 x 10^12 furlongs per fortnight
RE: Toyota uncontrolled throttle
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: Toyota uncontrolled throttle
Dan - Owner

http://www.Hi-TecDesigns.com
RE: Toyota uncontrolled throttle
Instituting a direct mechanical throttle "backup" linkage would likely put mechanical throttle positioning in conflict with where the DBW is trying to tell the throttle motor to put it. If either is given override authority over the other, the 'other' then becomes pointless.
Dan - at least one or two cars are already set up this way (and are reportedly somewhat frustrating to drive under certain circumstances). There are a few situations where brake and throttle use can overlap, either accidentally or by active intent, and in which electronically commanding a throttle cut might not be the best answer either. Electronic "sensing" is still a matter of inference from that which has already happened rather than direct observation and correlation to experience.
Norm
RE: Toyota uncontrolled throttle
Barring burnouts and such, I can't think of a reason why someone in an automatic would need to be pressing both the gas and brake at the same time (drivers are supposed to be taught not to drive with both feet). If the accident is hitting both pedals at once with the same foot, then the brake should still take precedence.
In a manual I see a somewhat "special" case of heel-toeing being allowed, but how often is that done in a Camry?
Tapping the brake, even accidentally, should act just like when the cruise control is on... the throttle plate is closed and the car begins to slow down. It wouldn't come to a fast halt, but the car would begin to slow down. If there was a failure in their programming that cause the brake pedal to be sensed when it wasn't being touched, the worst-case scenario would be a car that begins losing power... that's a stark contrast to what's happening now, continuing to apply power. There's certainly no need to verify and/or limit speed (as some have suggested on other forums) to implement this plan of attack.
Dan - Owner

http://www.Hi-TecDesigns.com
RE: Toyota uncontrolled throttle
I can also see it happening while rocking the car to extricate it from snow or, in some locales, mud.
Those are situations that anybody can encounter at any time, and are not at all associated with any sort of unusually "enthusiastic" driving.
Norm
RE: Toyota uncontrolled throttle
This morning it seems the recall has hit Europe and Asia, too.
Even some Ford models using the same part supplier...
Dan...Having spent a lot of time in snow country, I can attest to the absolute need of brake/throttle combo.
I have one vehicle with DBW...no problems in 170,000 miles. Even so, what's wrong with conventional mechanical/cable linkage? I've driven well over a million miles with only a couple failures and that was on race cars! Never on the street, even in my younger days and with all the hot rods I built. Even as a teenager, I could engineer reliable throttle linkage (made me popular, too
Rod
RE: Toyota uncontrolled throttle
Dan - Owner

http://www.Hi-TecDesigns.com
RE: Toyota uncontrolled throttle
Cheers
Greg Locock
I rarely exceed 1.79 x 10^12 furlongs per fortnight
RE: Toyota uncontrolled throttle
So DBW is looking pretty damn good from here.
Cheers
Greg Locock
I rarely exceed 1.79 x 10^12 furlongs per fortnight
RE: Toyota uncontrolled throttle
The 'DBW' concept is, in modern torque based EMS applications, used for handing over total control of the engines torque generation to the ECU. With the accelerator pedal position not relating to throttle plate position but requested engine torque (or, more, recently wheel torque).
This has benefits for interaction of auto trans, ESP etc etc. It also allows the ECU to select the most fuel economic 'setting' for a given drivers demanded torque and is especially useful when there are variable camshaft position, lift, wastegate control, swirl control valves and combustion mode where a simple throttle angle does not ensure an optimum setting.
MS
RE: Toyota uncontrolled throttle
I drive a Nissan Frontier Pick up truck, four cylinder engine, that is really kinda 'gutless'. I have noticed (and this is strictly subjective) that when I am on an ascending on-ramp, attempting to accelerate & merge with traffic, the truck 'feels' like it has much more power. It just seems to 'pull' and move right on out. It never makes the downshift to a lower gear. It seems to be a "sweet spot" as I add throttle, and accelerate up the on-ramp. Now, I am an old fart, and have driven my share of hot rod cars, in my time. This feels similar to another carb being activated with progressive linkage, or my old Volvo's turbo coming on speed. For some reason I don't notice it when overtaking & passing on a straight road.
Is the ECU clever enough to recognize "ascending on-ramp merging traffic" mode? I'm tempted to plumb in a manifold pressure gauge just to see whats happening during the 'event'.
RE: Toyota uncontrolled throttle
RE: Toyota uncontrolled throttle
Sorry...I apologize...I just couldn't resist...<snicker>
Rod
RE: Toyota uncontrolled throttle
RE: Toyota uncontrolled throttle
MS - the opportunity for improving fuel economy and emissions performance had occurred to me, as had the thought that automated rev-matching on downshift probably can't be accomplished in any other fashion. The other items on your list hadn't.
As Pat has noted, what would it take to provide the driver with ultimate override authority to select 'Neutral' or otherwise disconnect the engine from the drive wheels and let the PCM worry about the engine?
Norm
RE: Toyota uncontrolled throttle
Regards
Pat
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RE: Toyota uncontrolled throttle
RE: Toyota uncontrolled throttle
The recall has reached three continents and over 4 million cars! Even for a "simple mechanical fix" this has just gotta hurt.
My pals at the Ford dealer are jumping up and down...Sales with late model Toyota trades are 'booming'!
I've been through a couple big recalls in years past. Suffered through Nader's trashing of the Corvair (I had a new '64 Spyder)...Never anything like this, never!
Yep, this has just gotta hurt!
Rod
RE: Toyota uncontrolled throttle
I agree with PatPrimmer that the solution ought to be as simple as kicking it into neutral but I think that is obvious only to guys/(gals) like us who know how things work and how to operate the equipment like we want to when that is what is needed. When this first came to light, I, like Pat, thought what is so complicated about this. Just dump the clutch, right? These days, that is done by moving the stick one notch.
I was discussing this with the wife today while out driving as she had ask about the extent and nature of the problem and as a test, I mentioned Pat's solution and asked her if she would think to do this.
She said that she never would have thought of that and it was another (she has many) example of how engineers thought differently from normal people......
I shudder to think that I am sharing the road with people who can't figure out that kicking it into neutral (and listening to the engine scream) is a life saver. I have had to do it a few times in my life for unrelated problems, and it came second nature to me.
rmw
RE: Toyota uncontrolled throttle
Here's TTAC's take on dismantling the recalled CTS design vs the Denso one which is currently considered to be OK
http:
Cheers
Greg Locock
I rarely exceed 1.79 x 10^12 furlongs per fortnight
RE: Toyota uncontrolled throttle
I will stick to my VW.
Oh and plz stay away from automatic
Fe
RE: Toyota uncontrolled throttle
http:/
RE: Toyota uncontrolled throttle
Rod
RE: Toyota uncontrolled throttle
Dan - Owner

http://www.Hi-TecDesigns.com
RE: Toyota uncontrolled throttle
RE: Toyota uncontrolled throttle
Cheers
Greg Locock
I rarely exceed 1.79 x 10^12 furlongs per fortnight
RE: Toyota uncontrolled throttle
RE: Toyota uncontrolled throttle
It's probably a bit higher ratio than that considering only 20 or so fatal accidents.
I think that's part of why it took them so long to come up with a fix, trying to duplicate or surmise the problem.
DBW is better than cable from a manufacturing standpoint due to the fact it eliminates air bypass systems. Most cable throttle EFI cars have at least one, some have 2. One for loads, one for cold start. The DBW throttle body handles both the normal throttle function and load/cold-start air flow adjustments to maintain steady idle.
The automatics with optional "manual" paddle shifters have a more complex gated console shifter, if it's in the paddle mode you have to move it over and up to get to neutral. Maybe this should be re-thought to go back to the one movement to neutral.
Still think shifting to neutral is the best thing to do, it's easier to locate and slam the shifter up, most won't go to reverse without the release button. Easier than finding and turning the key and you don't lose your power steering/brakes. It should be part of every defensive driving course. Everyone that drives a DBW vehicle should practice in a parking lot.
You don't have to worry about hurting the engine, all DBW cars are rev limited and most are rev limited to 4,000rpm when the shifter is in neutral.
Maybe a kill switch system if you're going to use the complex remote keys, sort of like a dirt bike, only one easy access fool proof switch, all it does is kill the engine. But then you have to train drivers to drive without PS, PB.
RE: Toyota uncontrolled throttle
What ever it is, it is bad workmanship from some entity.
And a shame that people lost thier lives from it.
This should be a wakeup call for mandating strict emissions standards and forcing DBW or anyother type of control that removes the drivers input to the function and transfers it to a computer.
The other latest thing is computer controlled brakes in the hybrids, whats next?
RE: Toyota uncontrolled throttle
Dan - Owner

http://www.Hi-TecDesigns.com
RE: Toyota uncontrolled throttle
Just off the top of my head, allowing the throttle to snap shut as would typically happen with a purely mechanical throttle on a vehicle with a conventional manual transmission (think upshift here) is one example where emissions performance has "forced" some alteration in the relationship between the pedal and throttle positions. Has for a while.
Norm
RE: Toyota uncontrolled throttle
I don't get it. You mean it automatically controls the throttle for you?
Fe
RE: Toyota uncontrolled throttle
RE: Toyota uncontrolled throttle
Norm
RE: Toyota uncontrolled throttle
Rod
RE: Toyota uncontrolled throttle
Mazdas and Fords, and for that matter my Corona (Airpump/carb) did it as well. Not that it ever revved to 4000.
evelrod - nothing, or more accurately, whatever they programmed it to do. I drove 4 makes of cars and all allowed neutral to be selected while driving, two were definitely shift by wire. So until I find a car that blocks shifts into neutral I can't tell you!
dicer-virtually all computers of all types are basically built in SE Asia, statistically speaking. Especially the reliable ones.
Cheers
Greg Locock
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RE: Toyota uncontrolled throttle
Like an ECU will become erratic if a large amp power wire is routed in close proximity, something about electro-magnetic fields.
I've also seen cell phones clear immobilizer key chips when they are stored next to each other.
Another thing that happens is when a laptop is placed on a air bag seat occupant height sensor, it can cause erratic operation.
These critical throttle/brake electronic systems need to have the same rigorous safety measures and redundancies as the typical air-bag system. AFAIK no airbags have gone off by themselves and they are just as complex of a system.
RE: Toyota uncontrolled throttle
That's EMC or EMI testing, every design of car is checked for it, but the suspicion is that this doesn't catch every problem.
Other things include degraded or failed sensors, and unusual timing loops.
Cheers
Greg Locock
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RE: Toyota uncontrolled throttle
It may be just the media, but Toyota's "shim" fix was quoted as being fabricated from steel. Why not aluminum or plastic? It there an electromagnetic function to this part as well as defeating the otherwise-helpful friction damper?
I would guess the feed signal to the pedal is some sort of high frequency voltage or current and the sensor changes the inductance. Any knowledge here of the electrical details?
RE: Toyota uncontrolled throttle
RE: Toyota uncontrolled throttle
I know at least some of these cars are push button start and that requires holding the button 3 seconds to get the engine to "emergency" power off. So, these cars can be difficult to shut off in a panic situation.
So, it's the typical more than one thing causing most of the accidents. Once the throttle sticks, it's partly the driver not handling the situation well and it's partly the fact that the car can't be shut off easily which would be many persons first reaction in such a situation. Having decent panic situation training as part of the license requirements would certainly help with this problem, as well as helping in many other complete "fails" I've seen on the roads.
Greg's link shows pics of the disassembled pedal assembly and the fix looks quite plausible to me. The friction block operates via a lever connected to the return spring. The shim goes behind this lever and keeps the spring from either putting any pressure on the friction block or it limits the pressure on the friction block.
RE: Toyota uncontrolled throttle
Steel is probably cheaper than aluminum and more wear-resistant than plastic. No EM function...
Dan - Owner

http://www.Hi-TecDesigns.com
RE: Toyota uncontrolled throttle
Rod
RE: Toyota uncontrolled throttle
Fe
RE: Toyota uncontrolled throttle
Now things get weirder, the pedal maker says that the pedal issue is not a likely cause of SUA
http
and I don't suppose this bloke from NJ believes either of the recalls would help
http://t
Cheers
Greg Locock
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RE: Toyota uncontrolled throttle
Regards
Pat
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RE: Toyota uncontrolled throttle
Cheers
Greg Locock
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RE: Toyota uncontrolled throttle
I have been interested in that question from the first suggestion, but have not seen it convincingly confirmed or denied, which is odd, seeing as how crucially important it is with a runaway engine scenario.
Regards
Pat
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RE: Toyota uncontrolled throttle
Unless I personally have seen the problem or know someone who I trust that has seen it, I'm really not very convinced that Toyota has anything more than an issue that has been reported in a small number of cars and that they've been trying to diagnose it - as of now, they have found the pedal can stick and have concluded the pedal assembly is the problem. Only time will tell if that is so.
Once this started, the stories begin to circulate out of control. The idea that Toyota is hiding problems is great cover for the media and the lawyers love it too. Now, how many cases of people pressing the wrong pedal will just get blamed on Toyota building a faulty car?
It reminds me of the government here deciding to change the laws to add a bunch of roadside penaltes which remove the court system from the process. They used "street racing" to justify it. Just rattle on about how the law will solve the rash of street racing deaths and let the media run with it. It got competely retarded to the point that every single fatal accident was reported as "possibly street racing" that summer.
Anyone who thinks that the news media exists to report the facts is very dillusional. The news media exists to make the owners money....
RE: Toyota uncontrolled throttle
Dan - Owner

http://www.Hi-TecDesigns.com
RE: Toyota uncontrolled throttle
I have a few basic problems with ALL new cars that do not have a "key", "switch", that when activated kills the engine...RIGHT NOW, not in "three seconds".
Relying on the brakes to save you is a fools dream. In most cases of high speed acceleration, the brakes will simply fail if the power input cannot be interrupted by declutching, selecting neutral, kill switch or the like.
As most of you already know, I still drive race cars and have spent many years doing stupid "driver errors" that, for a non racer, could have been fatal. The ability to save 'ur a** in a clutch situation is only learned by actually doing it or by taking a class in such maneuvers and lots of practice. It must become a "reflex action" it it is to be affective.
Bottom line...Driver education. Common sense driver training classes in avoidance, panic, imminent crash, etc.
Too bad I do not see any of that in the future...Just more "safer cars" mandated by big brother.
Rod
RE: Toyota uncontrolled throttle
RE: Toyota uncontrolled throttle
Yeah, I know how simple a kill switch can and should be; wait till the guvvamint gets through with it.
Mike Halloran
Pembroke Pines, FL, USA
RE: Toyota uncontrolled throttle
Fe
RE: Toyota uncontrolled throttle
Incidentally this report is going for the jugular, but notice how the verbatims in the appendix (what the customer actually said) don't agree with the report that was entered into Toyota's warranty system. No wonder T wasn't taking them seriously. Unless that's what the service guys were told to do...
Cheers
Greg Locock
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RE: Toyota uncontrolled throttle
Funny though, I read the summary and it seems to be hinting that there is an electronic problem. Then, it says that brake to idle, which would be an electronic fix, may be the solution.
RE: Toyota uncontrolled throttle
RE: Toyota uncontrolled throttle
After reading the owner complaints, it is not hard to see that there is something more than a simple "shim" will fix.
Also, I found it odd that in the several occasions where the driver had the ability to select neutral, the engine simply over revved...apparently NO rev limiter.......???
I tried to simulate the unintended acceleration in the wife's Lincoln (with her protesting, I might add). The engine rev limiter dropped the rpm to 3000/3500 immediately selecting neutral. Also found that the ECM will not allow reverse at speed...good to know. Oh well, I'm NOT in Toyota's demographic anyway!
Rod
RE: Toyota uncontrolled throttle
I will say that I've had several issues with my C5 Vette accelerating while I was braking. Actually, it's more that it won't slow down even when I'm braking. When I depress the cluth during these events the engine revs up. However, I just move my right foot a little further to the left and the problem goes away...
RE: Toyota uncontrolled throttle
Rod
RE: Toyota uncontrolled throttle
The modern automatic shift system is actually quite refined. Most if not all auto shifters will go from drive to neutral by merely pushing the lever forward. You don't have to push the release button. Also the shifter will only go to neutral when you do this. It won't go to reverse unless you push the release button. Additionally most automatic shifters are mechanically connected to the trans so the shift to neutral is mechanical enough that it will shift to neutral without electronics.
In addition there's no way you can damage a DBW system by overevving, all are limited at redline in gear and most have a lower limit, 3,000 to 4,000 when in neutral or park.
IOW these cars are designed to be easily and safely shifted to neutral, and that is the easiest safest thing to do with a stuck throttle. Why the media is spending so much time reporting Toyota's downfall and all the problems and not telling people what they need to do, with ANY car with a stuck throttle, is indicative of their ignorance and their "public service" is lacking.
The fact that people are dying in stuck throttle cars is also indicative of the poor level of driver education in this country. If you can breath you can get a license. If people were trained to shift to neutral nobody would have died.This is something that should be added to all drivers ed courses because with the added complexity of DBW technology there is greater chance of things going wrong.
It would be interesting to see an engineer from a specific discipline related to trans control and/or throttle control weigh in on this thread.
RE: Toyota uncontrolled throttle
What this also means is you do not have to carefully "hunt" for neutral and worry if it's going into reverse or park, you merely slam the shifter forward in an emergency. It can only go to neutral if you don't push the release button.
RE: Toyota uncontrolled throttle
One of the fatalities lately, the Lexus in San Diego, was driven by a CHP veteran and safety instructor...That suggests some level of advanced experience, does it not?
One instance at a local Toyota dealer indicated that neutral could not be selected. ??? Another, the brakes failed to control the speed and the driver was able to "hold the off button" for the requires three seconds. A third driver selected neutral and the engine "revved uncontrollably" to the point of needing replacement from the dealer! Go back and read Greg Locock's post and inclusion, there are many more complaints filed with Toyota.
Many engineers posting here, including Mr.Locock, ARE experienced in the DBW and SBW systems in use today.
I don't think the "media" has gone overboard with this problem. Quite the opposite, in fact.
Rod
RE: Toyota uncontrolled throttle
RE: Toyota uncontrolled throttle
RE: Toyota uncontrolled throttle
Dan - Owner

http://www.Hi-TecDesigns.com
RE: Toyota uncontrolled throttle
then I should modify my statement to say, the Asian vehicles I'm familiar with go to neutral without the release and reverse only with the release. From a safety standpoint it seems to make sense.
I think the CHP veteran with the Lexus was a paddle shifter auto and he was possibly in manual mode which means neutral is over and up, not just up.
""That assume an automatic, correct? 'Cause I guarantee I can mechanically overrev a manual...""
Yes, and even with an auto it's probably going to go over one time, if it's floorboarded and put into neutral. But it's not going to stay there right?
RE: Toyota uncontrolled throttle
Cheers
Greg Locock
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RE: Toyota uncontrolled throttle
Luddite! Loom Smasher!
Out of interest whats your issue with DBW?
The cable operated throttle just does not fit in with modern EMS/Engine Hardware concepts and is grossly outdated on passenger vehicle engines.
From my point of view the problem is nothing to do with the actual engine management system per se but rather is a system integration issue.
By this I mean that the ECU was most likely doing exactly what was asked of it - which was exactly what the driver didnt want but the issue was the communication of thie wish ie the pedal mechanism. The issue laying with the pedal linkage sticking and keeping the throttle pot at some setting not desired by the driver.
MS
RE: Toyota uncontrolled throttle
The 'system integration' issue is that, while they're much better than they used to be, the connectors and internal interconnects used in automotive systems are not yet up to our expectations.
Mike Halloran
Pembroke Pines, FL, USA
RE: Toyota uncontrolled throttle
As more newer MCs are including DBW throttles, one hopes the E-stop switches remain hard-wired rather than sending a meek 'cease & desist' to the ECU!
RE: Toyota uncontrolled throttle
I was not aware the modern motorcycles were DBW, too. Just as well I probably will never own another one after I sell my '48 Norton this summer.....The "kill" switch (sic) is the compression release!
Rod
RE: Toyota uncontrolled throttle
RE: Toyota uncontrolled throttle
It implies that two near shorts would have to occur.
RE: Toyota uncontrolled throttle
RE: Toyota uncontrolled throttle
When you turn off the ignition switch, who is commanding fuel and ignition off? You or the computer system?
When you push on the gas pedal who is commanding it? You or the computer system?
When you push on the ABS brakes, who is commanding it?
You or the computer system?
Some nice detailed information on the systems would be nice.
RE: Toyota uncontrolled throttle
Makes it super-easy to do cruise control- gets rid of the vacuum motor and controls. That has to be a nice part of the cost savings.
Regards
Jay
Jay Maechtlen
http://www.laserpubs.com/techcomm
RE: Toyota uncontrolled throttle
There are two areas requiring additional discussion.
Surely there should have been high level behaviour boundary software present? Given the number and variety of accidents it is obviously there was not. ( I have worked on embedded sysems design).
Next why did not any of our departments of transport safety specialist catch this problem. They have known for years that software was going into cars. When new software is used for drive-by-wire, steer-by-wire or stability control then their is a public safety issue. Transport safety specialists MUST develope a capability to certify this software. They should have emulators/simulators that enable them to exercise in-boundary and out-of-boundary driving conditions.
As I said this is not just a Toyota problem. It is an early warning of major downstream problems unless changes are made now.
RE: Toyota uncontrolled throttle
b)no electronic problem has been confirmed to date- most incidents have been pilot error, some have been mats. Very few are unexplained, those might be hardware/software related, we just don't know.
c)apparently your expertise allowed you to miss point b, ie your expertise is borderline irrelevant
d) They don't have that expertise. In most cases they don't even see a new car before it is launched. You would need to certify the system, not just the software. They don't have the emulators. They don't have the people. They don't have the cars. Apart from that they are all set. Would this certification process include the effect of jamming the pedal with aftermarket mats? or drivers pressing increasingly hard on the wrong pedal?
It is not a Toyota problem, it is a combination of operator error and the media enjoying a beatup, admittedly aided and abetted by an approach to PR that seems comically inept in retrospect.
Cheers
Greg Locock
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RE: Toyota uncontrolled throttle
Did not mean to imply it was a sortware problem, ie your point (b).
We can take advantage of the embedded software to read sensors. Lets say we do a dynamic read of speed, brake presure clutch position and gas pedal pressure, and compare the data to recent past data. From the results we can determine if a driver/car is/are exibiting signs of acceptable behaviour.
The point is with sensors, correctly located, and appropiate software I think we can increase the safety of the car by detecting some mechanical problems. It gives us a capability we never had with 'just mechanical contrivences'.
I think my experience is relevant. GM obviously thought so. I gave a talk to a boardroom full of their execs in Detroit. The topic, the future of computers in the automotive and appliance industries.
Thanks for your comment.
RE: Toyota uncontrolled throttle
Dan - Owner

http://www.Hi-TecDesigns.com
RE: Toyota uncontrolled throttle
I still resent that I cannot legally use a 6 point full harness because it is not self adjusting just because some other dopes do not adjust their belts correctly.
Regards
Pat
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RE: Toyota uncontrolled throttle
It is not quite as simple as that, since simultaneous application of brake and throttle is a valid control state for some drivers in some conditions, and all drivers in one condition, unless they live in Holland.
Cheers
Greg Locock
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RE: Toyota uncontrolled throttle
Regards
Pat
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RE: Toyota uncontrolled throttle
I got it now. Not many hills in Holland
Regards
Pat
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RE: Toyota uncontrolled throttle
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: Toyota uncontrolled throttle
So, once this is implimented I'll have to use WOT on a regular basis or else the car will decide I'm making a mistake when I do try WOT and stop itself instead??
I think the media has just found a new, better story (BP).
But then, they're getting bored of that one too so hopefully something else fanciful but harmless will come along for them soon.