From: John Tserkezis on 11 Mar 2010 03:52
On 11/03/2010 4:25 PM, Jason James wrote:
>> Also note they are at least dual redundant (hardware and software)
>> Is the Priarse dual redundant in its accelerator/brake controls? Or
>> ANYTHING for that matter?
> Good point,..all ground aviatrion gear is either dual redundant by
> duplication or alternative system or in the case of some ATC comms/link
> equip triple redundant.
I did intend that comment a bit tongue in cheek, I don't expect them to
duplicate anything in a car, because the market won't stand for the cost
You can explain they have a choice, they can have it cheap, but expect
it to smash into things every so often, or, they can pay more, and never
ever smash into anything.
Users will *always* pick cheap. I know some may pick otherwise, but
they're so few I really don't care.
In aviation, that choice is (rightly) taken away from the end user.
If a car crashes, you might kill 4-5 people, and the driver is labelled
an idiot. When one plane goes down killing up to 1000 people in one go,
you can expect some questions to be asked.
All that said, if the cost won't allow for dual-redundancy, you can
afford extra software and testing without raising the price too far.
In the case of the Priarse, I would have expected they actually take
the thing out on a test drive before releasing it. If the issue is
being raised as much as I think it is, real testing would have seen it.
From: Noddy on 11 Mar 2010 05:06
"Diesel Damo" <Diesel_4WD(a)yahoo.com.au> wrote in message
> Wow. Someone with worse luck in cars than me. Thanks I feel better now :)
From: Noddy on 11 Mar 2010 05:16
"Clocky" <notgonn(a)happen.com> wrote in message
> One model from one manufacturer has zero relevance to any other model from
> any other manufacturer.
It would depend on who's making the steering controller. If the one fitted
to the current Corolla is found on other cars then it has the potential to
> I don't think so. For one electrically assisted power steering is a pretty
> simple system with fewer moving parts and less reliance on other parts to
> work and it's simply more efficient. Hydraulic power steering by
> comparison has many avenues of failure either directly or indirectly.
And yet hydraulic systems have proven themselves to generally be pretty
reliable over the years.
As I said, I don't have an issue with the technology or the hardware, but at
least a conventional hydraulic system is unlikely to ever try to turn the
wheels hard left because of a bit of dodgey computer code.
> ...and efficiency.
I think the efficiency difference between running a tiny power steering pump
and the extra load on the alternator in running an electric motor mounted on
the steering column would be incredibly hard to measure. On the other hand,
the difference in component costs per vehicle would be significant.
> It's been around since the very early 90's and used in mass production
> vehicles for over a decade.
In *some* vehicles. Mainstream would be more than half a dozen.
> Nice try, but disabling electric power steering doesn't disable steering
> either, it just makes the steering heavier much like hydraulic power
> steering failure does.
So why where you implying that it had some magical safety benefit?
> I wonder if the same scrutiny will now be applied to other manufacturers
> and what will be uncovered there ;-)
Probably not until they have problems. If and when.
From: Albm&ctd on 11 Mar 2010 06:35
In article <4b98400c$0$66788$c30e37c6(a)exi-reader.telstra.net>, me(a)home.com
> "John Tserkezis" <jt(a)techniciansyndrome.org.invalid> wrote in message
> > Show me one driver that cares about software updates that fix
> > everything, AFTER they've had their crash...
> Excellent point :)
> > When confidence in a product drops like that, who (well, anyone who
> > HASN'T been living under a rock) is going to buy a Priarse now?
> Only the completely stupid to the point of sheer bloody mindedness.
> I mean, you needed the 8's, 9's and 10's missing out of your deck to buy one
> when they *didn't* have issues, but if you bought one *now* the registration
> papers should come with a certificate that classifies you as legally insane.
I wanna cheap WOT one so I can save the whole farkin planet... and have a good
time speeding with an excuse.
I don't take sides.
It's more fun to insult everyone.
From: Noddy on 11 Mar 2010 07:21
"Doug Jewell" <ask(a)and.maybe.ill.tell.you> wrote in message
> I can understand Throttle-By-Wire on a Priarse where there is an electric
> motor involved, but on a vehicle like a falcon with only an internal
> combustion engine, what is the point?
> Certainly can't be cost cutting, 3 feet of steel cable would have to be
> cheaper than sensors, motors, and controlling circuitry.
Not on it's own no, but then by running an electric throttle they can
incorporate cruise control, A/C idle step up and anything else that needs to
change the rpm without needing any of the separate control actuators that
all these devices would normally require. The end result is all throttle
adjustments are made by the one device responding to computer signals which
is shitloads cheaper than having a device for each seperate throttle action.
> Can't be reliability - I've never heard of a throttle cable failing. The
> old pushrods use to have hiccups but cable is bulletproof.
I've had a few fail over the years, but when they did the throttle went
straight to idle and didn't cause a problem. Throttles stuck wide open
because of a failed throttle mechanism were rare, but even when they occured
the engine could be shut down instantly without needing to drive for 40km's
while pissing and moaning to emergency services on the phone :)
> Is it to make cruise control implementation better?
It certainly makes it cheaper.
Cruise has never really been difficult to implement, and it mormally doesn't
require rocket science to sort out. However older systems need their own
actuating device to pull on the throttle lever and make it work, and by
eliminating this they save quite a bit of money.
As to whether it works any better I can't say I've noticed a difference
> I don't know about other people, but I'm finding with more and more
> traffic on the road I use my cruise control less and less each year, to
> the point where I now couldn't care if a new vehicle had it or not.
Cruise control is my one "must have" item in just about any car as I get a
terrible back ache from holding my foot on the throttle for extended periods
and need to keep moving my leg around the floor. It also doesn't help that
my Rodeo has one of those throttle pedals that's in an annoyingly unnatural
position at freeway speed.
I'm desperately searching for a factory cruise kit for it but as yet haven't
> Is it to stop the drive-train self destructing because a hoon planted the
> throttle in N before shifting into gear? Surely prevention of that
> scenario could be done by cutting the ignition and/or fuel injection if
> the computer detected potential disaster.
There's ways around it, sure.
I know my Territory with it's FBW throttle will free rev if you shift from
drive to neutral with your foot on the throttle, but I've never attempted to
check if it'll prevent you shifting from neutral into drive with a boot full
of rpm. I expect that it won't, and I'm sure if I did it'd make a mess of
the mechanicals :)
> I really cannot see a suitable reason for a vehicle to have a purely
> electronic throttle, except for cases like the priarse where there is an
> electric motor in the equation.
Cost cutting is the only reason I can see it being an advantage.
To the manufacturer that is.