David Jenkins
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| posted on 30/10/13 at 10:15 PM |
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I think I'd want to retain the option to shove it into neutral at any time - the engine may end up screaming its nuts off, but at least I can
stop and do something about it.
The point about turning the engine off and losing brake servo assist and power steering is well made... It's amazing how hard it is to turn the
wheel without power steering - not impossible, but a real wrestling match.
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daviep
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| posted on 30/10/13 at 10:30 PM |
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quote:
Originally posted by Scuzzle
Turning off the ignition is going to work fine for someone who knows cars but some people are going to get caught out even if they have the savvy to
turn off the car at the key
When you turn off the ignition the servo brakes are going to stop working and so is the power steering and there will be people who won't know
to allow for this.
The brake servo will work just fine with the key turned off providing the engine is still turning, ditto for power steering unless it's EPAS.
Cheers
Davie
“A truly great library contains something in it to offend everyone.”
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morcus
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| posted on 30/10/13 at 10:31 PM |
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I didn't think not having power steering was much of an issue when moving at moderate to high speed? The brakes I can see being an issue though.
In a White Room, With Black Curtains, By the Station.
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PSpirine
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| posted on 30/10/13 at 10:37 PM |
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To clarify, Toyota, as well as other manufacturers (including the one I work for) have a HOLD TO OFF on push-button ignition systems if the car is in
motion.
You hold the stop/start button for I think 2-3 seconds and it will ignition off (safely), even if you're driving. This does NOT engage the
steering lock, although I'll be honest I've done only a few trials.
This is to stop the engine being accidentally turned off on a motorway if you push the button by accident when reaching for an air vent or other
button.
I appreciate that some people may be unfamiliar with certain cars, but that is no excuse. If you get into a manual car with reverse under 5th rather
than to the left of 1st, and you drive over a child in a car park, are you going to blame the manufacturer because you weren't familiar with the
layout of gears and went forwards instead of backwards?
Equally, not knowing that you lose servo and power steering if you turn the engine off.. This is mentioned in pretty much any literature, including
car manuals, instructions when towing, instructions when being towed.
P.S. The steer-by-wire system which will be shortly introduced (by Nissan I think?) has an entire mechanical system on standby as a failsafe. THIS i
find entirely useless, why even bother with steer by wire, if you have to lug around a full mech setup, when EPAS can deliver all the same features
(auto-steer/parking etc.).
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dhutch
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| posted on 31/10/13 at 04:20 AM |
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Hadnt heard the news, as im in a bit of a bubble at the moment, but I must say while I wouldn't be a fan of steer-by-wire and dont like electric
handbrakes, fly-by-wire throttle (and planes) done worry me that much.
I have only ever had a throttle-stick moment once, and that was in the kitcar, with a cable. I grabbed the key, which was a mechanical on-off switch,
and killed the engine mid bend while on the brakes. No steering lock.
As for why people done bring a run away car under control, amongst other issues mentioned, sheer blind panic and lack of time has not been mentioned
much. When the kits throttle stuck, and not at full bore, it was about the most frightening thing ive witnessed in a car, and there was not a lot of
road about to have much time to think.
Daniel
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David Jenkins
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| posted on 31/10/13 at 08:49 AM |
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quote:
Originally posted by PSpirine
To clarify, Toyota, as well as other manufacturers (including the one I work for) have a HOLD TO OFF on push-button ignition systems if the car is in
motion.
You hold the stop/start button for I think 2-3 seconds and it will ignition off (safely), even if you're driving. This does NOT engage the
steering lock, although I'll be honest I've done only a few trials.
This is to stop the engine being accidentally turned off on a motorway if you push the button by accident when reaching for an air vent or other
button.
But would this still work if the car's management system is stuck in a loop? Would it even be monitoring the on-off button, or respond to an
interrupt as a result of pressing the button? This sounds like a software solution to a software problem! I'd still prefer a
non-computer-controlled override.
I do agree with the rest of your post though - don't blame the car if you can't be bothered to read the manual to learn how it all works.
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mcerd1
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| posted on 31/10/13 at 08:58 AM |
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quote:
Originally posted by daviep
quote:
Originally posted by Scuzzle
Turning off the ignition is going to work fine for someone who knows cars but some people are going to get caught out even if they have the savvy to
turn off the car at the key
When you turn off the ignition the servo brakes are going to stop working and so is the power steering and there will be people who won't know
to allow for this.
The brake servo will work just fine with the key turned off providing the engine is still turning, ditto for power steering unless it's EPAS.
Cheers
Davie
the servo should still give you at least 1 good push off the pedal even with the engine completely off as is holds a reserve vacuum (and most will
give you 2 - 4 pushes of the pedal before the assistance is completely gone)
and as above the loss of power steering at speed should be manageable
but quite a few years ago I read something about an old couple who's mk1 focus had cut out at speed (some kind of electrical gremlin in the
ignition that they got recalled for I think)
from what he said it was clear that he'd hit the brakes 2 or 3 times, but not held them long enough to loose much speed - at that point
he'd lost the reserve vacuum and the power steering - or in his words "they went solid and stopped working" so he let go of the
steering wheel, took his feet off the pedals and waited to hit something 
(as it turned out that was a 3-4m drop off the side of the banking into some trees)
just shows you how some people can react in that situation - personally so force on earth would stop me from standing on the pedals and wrestling with
the steering even if they really weren't working at all...
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PSpirine
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| posted on 31/10/13 at 09:35 AM |
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quote:
Originally posted by David Jenkins
quote:
Originally posted by PSpirine
To clarify, Toyota, as well as other manufacturers (including the one I work for) have a HOLD TO OFF on push-button ignition systems if the car is in
motion.
You hold the stop/start button for I think 2-3 seconds and it will ignition off (safely), even if you're driving. This does NOT engage the
steering lock, although I'll be honest I've done only a few trials.
This is to stop the engine being accidentally turned off on a motorway if you push the button by accident when reaching for an air vent or other
button.
But would this still work if the car's management system is stuck in a loop? Would it even be monitoring the on-off button, or respond to an
interrupt as a result of pressing the button? This sounds like a software solution to a software problem! I'd still prefer a
non-computer-controlled override.
I do agree with the rest of your post though - don't blame the car if you can't be bothered to read the manual to learn how it all works.
It should do, there are clear priorities within the CAN network. I appreciate that there were a lot of inefficiencies and lack of robustness found in
the Toyota code, so it is possible that the system went into meltdown, but I still highly doubt it would override the ignition switch.
Pushing the ignition switch (holding it to OFF the car) would kill power via the Body Control Module and would switch the Power Distribution Module to
the correct ignition-off power mode. So even if the ECM is stuck in a WOT loop, it shouldn't make any difference. On the CAN system, the
ignition kill should have pretty high priority, short possibly only of the airbag and emergency crash system signals.
Obviously I can't speak for Toyota, and if indeed they don't prioritise their CAN messages accordingly, then yes what you say is
technically possible, but unlikely. Especially since most of the reports say the driver "did not know that you have to hold the button to turn
the car off".
I'm sure it's possible to find problems in ANY code, whether it's a car, plane, computer, or banking system, given a big enough
witchhunt, which this does sound a bit like.
I'm going to have a play around with my Prius on an empty stretch of road, and see what happens under WOT conditions.
One runaway I had was a Rolls Royce Silver Shadow with its pneumatic "bellows" cruise control. Switching cruise control on, just locked
the car into WOT. Now THAT was scary 
Can't stand electric park brakes by the way! They aren't a safety hazard, as they always tend to fail in the ON position when parked, but
still bloody annoying.
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mcerd1
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| posted on 31/10/13 at 10:08 AM |
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quote:
Originally posted by PSpirine
Can't stand electric park brakes by the way! They aren't a safety hazard, as they always tend to fail in the ON position when parked, but
still bloody annoying.
My issue with electric handbrakes is that most seem to be able to be released without the key in the ignition (or some other cut out)
so when we take our kits for an IVA test the mechanical lever has to withstand being knocked off accidentally (i.e the ratchet needs to be good enough
not to let go when you push the lever or knock it sideways)
one or two cars I've been in with electric handbrakes have the button in the middle where you'd expect, yet apparently its good enough
just to have a few seconds delay on the button before it takes the brake off - so when your reaching into the back to get something and accidentally
lean on the button...
...just lucky I wasn't close enough to hit anything
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coyoteboy
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| posted on 31/10/13 at 12:48 PM |
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quote:
"they went solid and stopped working" so he let go of the steering wheel, took his feet off the pedals and waited to hit something (as it
turned out that was a 3-4m drop off the side of the banking into some trees) just shows you how some people can react in that situation - personally
so force on earth would stop me from standing on the pedals and wrestling with the steering even if they really weren't working at all...
And that's why your genes should continue on and his should have been halted in their tracks.
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scudderfish
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| posted on 31/10/13 at 01:21 PM |
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quote:
Originally posted by PSpirine
Especially since most of the reports say the driver "did not know that you have to hold the button to turn the car off".
I would like to ask people who claim this what they intended to do at the end of the journey. Leave it idling until it ran out of fuel?
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mcerd1
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| posted on 31/10/13 at 01:33 PM |
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quote:
Originally posted by scudderfish
quote:
Originally posted by PSpirine
Especially since most of the reports say the driver "did not know that you have to hold the button to turn the car off".
I would like to ask people who claim this what they intended to do at the end of the journey. Leave it idling until it ran out of fuel?
^^ I'm guessing you just touch the button when your not moving to stop it
a bit like a PC - to shut down normally you close all you programs, then touch the on button and it'll shut down properly
(ie. stop the car, but the handbrake on and touch the button to stop the engine)
but if the thing locks up completely you may need to force a hard shutdown - on most PC's / laptops you do that by holding the power button down
for ~5 secs
(ok with a desktop PC you can also pull the power cable out the wall - but the car equivalent of that would be disconnecting the fuel lines at 70mph
which could be a bit tricky )
[Edited on 31/10/2013 by mcerd1]
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PSpirine
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| posted on 31/10/13 at 01:57 PM |
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quote:
Originally posted by mcerd1
quote:
Originally posted by scudderfish
quote:
Originally posted by PSpirine
Especially since most of the reports say the driver "did not know that you have to hold the button to turn the car off".
I would like to ask people who claim this what they intended to do at the end of the journey. Leave it idling until it ran out of fuel?
^^ I'm guessing you just touch the button when your not moving to stop it
a bit like a PC - to shut down normally you close all you programs, then touch the on button and it'll shut down properly
(ie. stop the car, but the handbrake on and touch the button to stop the engine)
but if the thing locks up completely you may need to force a hard shutdown - on most PC's / laptops you do that by holding the power button down
for ~5 secs
(ok with a desktop PC you can also pull the power cable out the wall - but the car equivalent of that would be disconnecting the fuel lines at 70mph
which could be a bit tricky )
[Edited on 31/10/2013 by mcerd1]
Correct, when parked, it's instant touch to ignition off. When in motion, it's got a 2-3 second hold (not sure on the exact time) to turn
the car off, for (what seems to me) obvious reasons.
The computer shut down analogy is an interesting one - people clearly are aware of that operation mode, so if anything, the hold sequence is more
intuitive than panic "push several times in quick succession to turn off" which is what the prosecution seemed to suggest should trigger
an ignition off.
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hughpinder
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| posted on 31/10/13 at 03:28 PM |
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I would have said holding a button in for 2 or 3 seconds in an emergency situation was pretty hard mentally. Yes, sat here now, no problem. Sat on the
motorway at 70, probably no issue either.
But, if you are pushing on a bit down some lanes, reach your braking point and start braking, and the engine keeps on pulling you onwards (thus you
are probably already beyond the point where you are going to make it round the corner by the time you decide you need to do something else, like
stopping the engine) I would suggest it takes someone with extraordinary self control to continue to lean forwards (which I have to do to reach the
button in all the push button cars I've driven - all dash mounted buttons) hold a button for 3 seconds (if you can while steering), while
steering throught the Zeds one handed, and not taking your finger off the button to try anything else like changing gear. If you ever look at books on
human interface design for computer systems, the normal figure quoted for a reasonable response that people see as instant is 0.2 seconds or less,
with recommendations that if an action takes more than 0.5 seconds for the computer to complete, then it should give some indication that it is
acting, like displaying an egg timer symbol or similar. Any longer than that and people assume 'its not working' and will start to look
for something else to try.
Personally I'd like to think that dipping the clutch or selecting neutral in an auto would come to mind before trying to turn the engine off,
but once you've decided on a course of action in a stressful situation, people tend to try very hard to achieve whatever they have decided to
do. I have to do incident investigations as part of my job, and it is quite amazing how hard people will try to do the wrong thing once they have
decided that that's the way forward, and afterwards admit that it was obviously the wrong thing if they had stopped for 2 seconds to think about
it.
Regards
Hugh
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mcerd1
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| posted on 31/10/13 at 03:50 PM |
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quote:
Originally posted by hughpinder
Personally I'd like to think that dipping the clutch or selecting neutral in an auto would come to mind before trying to turn the engine
off
I think the single biggest problem with the toyota in question is it had an extra 'safety feature' that stopped you putting the autobox
into neutral on the move - in doing so they basically removed the last catch-all safety net 
I've had sticky throttles and engines cutting out at speed - with both the situations would have been a lot lot worse if I'd not had a
clutch pedal (but even an auto that you can stick into neutral would have been almost as good)
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hughpinder
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| posted on 31/10/13 at 03:56 PM |
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If anyone is interested in 'steer by wire' thing here's the article. Seems way overcomplicated, with many things that can go wrong
compared to the old fashioned set up, and few advantages. Mechanical override that engages if there is an emergency - I wouldn't want to rely on
that when the car is 10 years old and it hasn't operated once in all that time!
http://www.driving.co.uk/features/infiniti/help-someone-s-reinvented-the-steering-wheel/15630
Anyway, Enjoy
Hugh
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mcerd1
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| posted on 31/10/13 at 04:56 PM |
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re: drive-by-wire steering
the only reason I can see for going to all that effort, including the 'simulated resistance' you feel at the wheel is so that they can
compensate for a badly designed steering setup and make it feel like a nice steering setup
is 'fake' feedback at the wheel really going to tell you how the tyres griping in the bends ?
I recon if this takes off then driving most cars is going to give you that same disconnected feeling you get from a arcade driving game or your xbox
etc....
even the engine noise you here is being 'simulated' on some cars just to add to the unreal computer game experience where what you feel
and hear while driving has nothing to do with the reality of whats actually happening 
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coyoteboy
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| posted on 31/10/13 at 06:11 PM |
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quote:
Originally posted by hughpinder
I would have said holding a button in for 2 or 3 seconds in an emergency situation was pretty hard mentally. Yes, sat here now, no problem. Sat on the
motorway at 70, probably no issue either.
But, if you are pushing on a bit down some lanes, reach your braking point and start braking, and the engine keeps on pulling you onwards (thus you
are probably already beyond the point where you are going to make it round the corner by the time you decide you need to do something else, like
stopping the engine) I would suggest it takes someone with extraordinary self control to continue to lean forwards (which I have to do to reach the
button in all the push button cars I've driven - all dash mounted buttons) hold a button for 3 seconds (if you can while steering), while
steering throught the Zeds one handed, and not taking your finger off the button to try anything else like changing gear. If you ever look at books on
human interface design for computer systems, the normal figure quoted for a reasonable response that people see as instant is 0.2 seconds or less,
with recommendations that if an action takes more than 0.5 seconds for the computer to complete, then it should give some indication that it is
acting, like displaying an egg timer symbol or similar. Any longer than that and people assume 'its not working' and will start to look
for something else to try.
Personally I'd like to think that dipping the clutch or selecting neutral in an auto would come to mind before trying to turn the engine off,
but once you've decided on a course of action in a stressful situation, people tend to try very hard to achieve whatever they have decided to
do. I have to do incident investigations as part of my job, and it is quite amazing how hard people will try to do the wrong thing once they have
decided that that's the way forward, and afterwards admit that it was obviously the wrong thing if they had stopped for 2 seconds to think about
it.
Regards
Hugh
I'd agree, it's less intuitive than a normal standard manual car. It's probably more dangerous because of it, and in a situation
like an NSL at night in the dark it's going to lead to death. But then so's most occurrences of a sticky accel if youre pushing hard
enough on a public road to miss your braking point in the half a second or so it takes to realise the accel is stuck.
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