Oh brother! On the news they explained it could be cosmic rays flipping bits in the computers that cause unintended acceleration. We've seen "vandal EMPs". What's next! Aliens? Just face it. The most likely cause is the driver! Now it's possible there is a design flaw, but not in the way many think. It could be the ergonomics causes people to hit the wrong pedal, as in the Audi problem of a decade ago.
Record the data, then investigate software and electronics if the data says it is not driver error. Seems pretty simple to make it go away. Add brake override of throttle as NHTSA suggested since 2007 and audi has implemented, for the cases where it is not operator error. Toyota said it will do the later, but has been less than forthright on the data recording and investigation. IMHO there is statistically significant data that suggest toyota may have unintended acceleration not caused by user error that is causing car crashes and fatalities.
Make it a universal rule and I'm with you. But a suggestion is not a mandate that all manufacturers must follow. Source? I've seen some light-weight trend data from the NPR report but there are other factors that need to be accounted for: Driver age - the data I've seen suggests older drivers have a higher ratio of some types of accidents. We've already seen suggestions that Toyota owners tend to be an older group. Very small numbers - even our Prius fatality studies had to collapse multiple years to get statistically significant numbers. The problem is the more years collapsed, the greater the probability other errors can affect the results. I have no problem with a safety regulation that is universal for all vehicles. I have a big problem with a safety regulation specific to one manufacturer. Bob Wilson
There is a different issue here. The main point I was making is that for the weird suggestions to go away, Toyota needs to show there is user error, not just blame the driver. They can do this by complying with the NHTSA's mandate of precollisional edr data. Then making it easily accessible for drivers that have gotten into crashes to read said edr information. The mandate has not yet gone into effect, but not yet having production code on your edr reader is not a major trust builder. I do not know if the data being logged complies with the mandate.
To compare those numbers of Ford vs. Toyota fatalities you need to have the number of cars of each manufacturer that is/was on the road during that period so that you can get a percentage and accurate comparison. If Toyota has 2.5x as many cars on the road then they have a similar track record.
You can get a clue to this answer by looking at this:NPR Vehicle Acceleration Complaints Database : NPR Sure it would be nice to have recorded data on the car. But we can't make something from nothing. Besides, there is a downside to having that information readily available. Your insurance rates could sky rocket and you could find that you suddenly have no defense for that ticket. Frankly, I would welcome having it. I am personally aware of one Camry which was equipped with a throttle/brake override at the recall so this is being done. I am a candidate for user caused "unintended acceleration". I had hand controls installed on my Prius. That, to me, is the kind of action which is indicated by all of this fuss. There clearly are some who passionately feel that Toyota is at fault here. I am not sure that ANY amount of logic will change their mind. They come right out and say that their belief will not be changed by logic.
I have a question for all the experts? If you were going 90 mph and you put the brakes on, wouldn't you be in regen?? That's how mine works. (but I've never gone 90) Prius Prime Donna
I would like diagnostic data logged also, that is a different matter. For edr all I am asking for is that toyota speed up compliance with the edr mandate. That means actually putting production software in the reader, and logging data to standards. No one has gotten a speeding ticket from Ford, GM, or Chrysler compliant data recorders. The requirements would not have data about speeding in it except in the case of an accident. These are the cases that have used edr records against the driver. Toyota has been putting up a straw man argument about privacy, then going to court to prevent drivers from seeing their private information. My insurance went up when I was hit twice, neither of which was my fault. Car insurance does not refuse payment when the driver is at fault either.
No, not if the go-pedal is off the peg at all. Regen only happens when your go-foot is *lifted*; otherwise it's all hydraulic if you two-foot it and start pressing the brake too. I explained all this in another thread, or earlier in this one, or whatever; it's all gotten to be such a confusing welter of crap and hairbrained theories I can't remember where I tried to drop factual clues anymore. I'm thinking to go collect it all and do a second big writeup or something, but nobody's gonna pay attention anyways. . _H*
I'm not an expert, but you would quickly go into friction braking as only very light pedal pressure. At high speed, the regenerative braking components max out quickly. The energy that must be used to stop the car is proportionaly to the square of the speed. It take four time the braking energy to stop from 90 as it does from 45 so friction must come in earlier. In either case a data log would not show anything, unless you turned the car off, hit something, or other triggers were being used (braking while accelerating is a great candidate for logging). I have no idea if a prius will keep the log when the car is turned off. Note, I was not really talking about soft deceleration while pressing the throttle, for that look at hobbit's answer. I wonder if the gen3 also has this strange characteristic, or looks at both inputs and decides what the driver might have wanted. Hobbit, I too would be interested in your summery.
I'll answer anyway. Regen is limited by the battery current limit. An ideal theoretical calculation (i.e. ignoring real world inefficiencies) indicates that at 90 mph, that limit is reached at about 3% of the braking force that the tires can apply to the road. I.e. at high speed, the regen limit is reached with very light braking. Hard and even moderate braking requires the friction pads. And don't forget Hobbit's answer -- foot on the gas means no regen.
