Safe Speed Forums

I find CC very useful as my car actively wants to go faster than I do on multi-lane roads.

I 'hover over' the brake as this is where I expect to need my foot to be next. If only I'd thought it through!!!

Homer, the key is this: Foot from accelerator to brake is a spontaneous reaction. Foot hovering over brake to brake is a choice reaction (although you may feel its "natural" and "spontaneous") and hence time saved in transfer time is lost by choice reaction time. Thats the science. But if you know better please correct my post of braking time.

It's interesting that ed_m agrees with me on this point and he has studied Vehicle Dynamics at Loughborough Univerity.

Surely that depends if covering the brake is natural to you or not?

If you don't do it, it won't be; if you do, it will.

I’m not sure ed_m did agree. From what I gather he seemed to be on the fence, and that was relating to skidpan training – unless you are referring to a post in another thread?

For me, this seems to be the crux of our difference:


Surely the decision to keep (or to have kept) the foot on the accelerator is also a choice? If what you say is correct, then surely the differences would be cancelled out by the choice to keep the foot on the gas?

Also, I don’t understand how a spontaneous reaction wouldn’t override a choice reaction.

_________________
Views expressed are personal opinions and are not necessarily shared by the Safe Speed campaign

hmmmmm you had me confused there too... had to check back to my last post which was i think fence sitting on the skidpan issue.

braking response time sounds more like a human factors thing than vehicle dynamics.

i use my CC frequently and do it for comfort & convenience... i've never considered improving safety.. given that my right foot is often comfortably on the floor.
how much this might increase my response time i dont know, not a great deal i'd guess.
of course i'm predominantly using it in light traffic conditions, anticipating any trouble and covering the brake and/or 'suspend' switch as and when.

Correct, but the reality of the scenario in case, is a driver that only does this in fine weather.

I do left-foot braking quite competently and regularly, to some passengers it would appear to be a natural reaction. However despite attaining a high skill level, left-foot-braking, is still a choice reaction and not a spontaneous reaction like right-foot-braking. So right foot will be quicker in an emergency, even if the left foot is hovering the brake.

I doubt that anyone operates 'foot hovering' anywhere near enough to make it a spontaneous reaction.

You may feel faster because your transfer time seems quicker, but what you can not detect is the time it took to make that choice reaction, therefore you can not judge the matter yourself. However, find road where you can do say 80mph, get a friend to randomly slap the dash board for an emergency stop, with a stop watch to measure the difference in stopping times.

Whilst I have left-foot braking and other specialist techniques in my 'tool box', in an emergency, I abandon such 'advantages' for the greater benefit spontaneous reactions.

Steve: The bottom line is this. It is quicker to make a spontaneous reaction and transfer time from throttle to brake, than it is to make a choice reaction and transfer time from above brake to brake.

We will never agree, because it seems that you insist that both are spontaneous reactions. I would like elaborate with technical references but you are aware I am currently not really bothered if you wish to accept there is a difference between these two processes and the reactions behind them.

ed_m: I may have got the wrong end of the stick, but I thought that you were agreed in principle that 'brake-hovering' is overall slower.

I read that you had studied Vehicle Dynamics and has assumed that human reactions and thought processes would have been ties up in that subject particularly in the area of braking - obviously I was wrong.

Nope. I suspect there has been a mixup between the difference between spontaneous reaction and choice reaction, and choice to keep on the gas and choice to hover.


My bottom line: no explanation, reasoning or supporting evidence - no reason for anyone to accept.

Could someone else try to explain this (from my previous post) to me?




Wait, let me get this right:
You were (wrongly, but I won't dwell on it) claiming you had support from someone with the necessary technical credibility, but now that you're shown you don't actually have that support you simply dismiss that technical credibility? I'll let the reader decide on that one.

If I told you that the moon travels around the earth, you’d say “prove it”. But as you know I am currently not exerting myself to give references I understand that if you can not google them, then you won’t accept them either.

A choice reaction is slower than a spontaneous reaction – do you really find that impossible to accept? Do you understand the terminology? Have you studied anything like this?

I really do not see what you are driving at with ed_m. I had assumed that from his post agreeing in principle, that this was based of his studies of this area of Vehicle Dynamics. It now seems that ed-m has not studied or not remembered this aspect and so was making an educated opinion based on common sense. Nevertheless he agreed in principle.

Strawman (it begins).
There is a gulf of difference between one person giving unsubstantiated claims (going against reasoning already given) and the wealth of science, evidence and educated opinion all being on one side of the argument.


Of course I accept that, it's fairly obvious; this isn't what I'm questioning (I thought I had already made my questions very clear).

Lucy, please don't respond if you're not going to answer the following:

- Does the spontaneous reaction over-ride the choice reaction when needed? If not then please can someone explain it to me.
- If not, is the choice to keep the foot on the gas pedal the same as the choice to hover it over the brake pedal? Again, if not then please explain.

_________________
Views expressed are personal opinions and are not necessarily shared by the Safe Speed campaign

Foot where?

Reaction time is irrelevant. I'm not using CC when reactions will be required.

And as discussed several times before, if you are relying on your reactions to get out of trouble then you are doing it wrong.

COAST

If we recognise the emergency of a scenario, a spontaneous reaction is most likely to take place – but that doesn’t mean that the spontaneous reaction is the correct one!

A spontaneous reaction can’t over ride a choice reaction or visa vera – we have no control over how we react. But an overall reaction may be a sequence of different types of reactions.

The detailed reality of the scenario we are considering is that in emergency braking, the first reaction will be a spontaneous one (to move foot from throttle to brake). Then a choice reaction will have to be made to actually direct the foot to the pedal. Even if the foot stays above the pedal, ie the choice reaction takes place before significant muscular movement, or there is no spontaneous reaction, a choice reaction will be made.

What we will never agree on is that in reality braking from a hovering foot is a choice reaction – not a spontaneous one.

Keeping foot remaining on throttle or hovering the brake is not a reaction

But is can be the correct one too, and many events have to have evolved before the 'emergency action is even required'. With proper training people do react better, and do not necessarily, 'go off' and use those skills recklessly. Training gives people more knowledge and better understand of all the dangers, which can often, enable people to use those skills productively rather than negatively. That leads to people's attitude and their approach to the training, whether it is 'forced', or done through desire to learn.
Many people learn more easily than, perhaps you might be giving them credit for, ask any Fleet Managers or Car Driver training schools ... their results are less accidents, which tell companies that a day training can make 'all' the difference.
No, it does not make them an expert, but that was not the goal. It can be just being more aware on the road, and prevent the situation all together, to doing the correct action, and being better off because of that action. It may prevent an accident, it may not, but perhaps just better off, or with less damage perhaps.

There is also the 'lizard brain' which involves the 'automatic reaction'. The instinctive (or well learned actions), becoming totally instinctive.

A spontaneous reaction can’t over ride a choice reaction or visa vera – we have no control over how we react. But an overall reaction may be a sequence of different types of reactions. [/quote]

If your spontaneous reaction, is an immediate one, and your 'choice reaction' is like a decision?, then what difference do you see in either?
We do have control over how we react for almost everything that we do in the car, we will do so to differing degrees. Many events can alter how we react, including, experience, training, education, awareness, skills and ability.
At what point do you see an action to positively correct a bad re-action, an action, as opposed to a re-action ?



Don't think that I agree.
If we look at the meaning of spontaneous : (Oxford Eng Dictionary) :
A adj. 1 Performed or occurring without external cause or stimulus; coming naturally or freely, unpremeditated; voluntary, done of one’s own accord; (of literary style etc.) gracefully natural and unconstrained. M17.b Of a person: acting voluntarily or without premeditation; tending to act in this way; unconstrained, uninhibited, natural. M18.2 (Of movement or activity in an organism) instinctive, prompted by no motive; (of sudden movement etc.) involuntary, not due to conscious volition. M17.

This would therefore imply that you 'place the foot from the throttle to the brake, naturally from it's location in an unconstrained natural manner and instinctively. This therefor implies far less 'thought process' than you appear to be crediting it with. The aim of a driver is to 'hit the brake' the aim being to teach an instinctive, taught, immediate reaction, as fast as possible.
A 'choice re-action' or as I think you mean, a 'thought process', then no, the whole aim is that the hit the brake, is not 'thought out'. The danger is noticed, and an immediate instinctive action is involuntary, it is NOT thought out.



Perhaps not but debate is good.
I do not think that it is 'either' given a real emergency situation, BUT a thought process 'follows' and then any training, education, and one's own ability, start to come in to play, in a following instinctive manner, but if you have to 'stop to think' then one is likely to have 'no time to react' at all, as accidents happen 'so fast', usually.
I think it is more involved than you have given it credit for too.
The 'hoover over brake peddle' is often pre-emptive thoughts, as there is a strong likelihood of the desire to use, even if only momentary unless used deliberately for many driving purposes, and for specific precise needs. Many of those uses are 'thought processes' within standard driving (not ideal). To keep a foot on the throttle is standard driving, with many varieties of thought and non-thought process at 'play'.

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Safe Speed for Intelligent Road Safety through proper research, experience & guidance.

I fear you have.
Previous to this and the last response I think I'm correct to say my only other post on this thread was page 1:





You read correctly, I did study that along with a variety of other automotive linked topics. There's a clue in the name tho.. vehicle dynamics.. dynamics of the vehicle.. human factors & driver modelling is of course a linked and important topic but not on i have personally studied in any great depth.

Please don't drag me into this any further !
Trust me, if I want to offer an opinion I will

Claire/SafeSpeedv2

Firstly, under the circumstances, I have not sought out the technical references that I might otherwise have done.

The impasse is caused by people believing that “braking from hovering” is a spontaneous reaction.

You are now introducing training – training in “brake hovering” is not what is being discussed.

The difference between spontaneous reaction and choice reaction is the thought process behind them, hence the time difference. But they are both still reactions as oppose to decisions.

I’m glad you said “We do have control over how we react for almost everything”. In the scenario that we are discussing, we are considering reactions, NOT decisions. The reality is in an emergency braking situation, as being discussed, we make a spontaneous reaction of which we have no conscious control.

If a pedestrian steps in front of me I can not stop myself braking and steering to avoid a collision. However, subsequently a choice reaction may make me accelerate, hand brake or whatever to avoid an accident. Once that choice reaction had been made, I would be unable to over ride it while under emergency conditions. Again this is the impasse here, some people believe that the subsequent decision to accelerate is a spontaneous one, its not, it’s a choice reaction.

Ultimately, my choice reaction may have been to run the pedestrian down as avoidance would have taken more lives. Even if that choice was in fact wrong, under criminal liability, I would be considered an automaton (not in control of my actions/reactions). The relevant law is Hill v Baxter [1958] 1 QB 277.

Your question was “At what point do you see an action to positively correct a bad re-action, an action, as opposed to a re-action ?
My answer being that whilst under an emergency situation, there are only reactions, no decisions.

Well I see you wish to disagree on spontaneous ‘throttle to brake’ reaction, and choice ‘above brake to brake’ reaction. Language dictionary definitions are not appropriate to scientific use of the word.

Your problem is with the terminology. You see both spontaneous and choice reactions, as dictionary definition spontaneous, and indeed under the dictionary definition they are. But science makes the distinction as there is a difference in time due to the processes involved.

On the issue of pre-emptive thought or as I would call anticipation, you make a very good point. Your reactions are dramatically enhanced. For example, if you drive round a blind bend and anticipate that there may be a cow on it, you will probably be feathering the brake, so reducing foot transfer time etc and indeed the subsequent braking (should a cow appear) will be spontaneous, and a faster spontaneous reaction for the anticipation.

However, the Cruise Control situation we are debating, the poster clearly said that he only applied CC in safe conditions. Therefore a general wareness that things might change is not the same as anticipation in reactions. If he was genuinely anticipating, he would be feathering the brake – this is not what is being described.

I feel that I must now close the debate on this particular Cruise Control braking scenario as I feel that I am repeating myself and have nothing else to add.

However on the subject reactions, perhaps I can share some entertaining if not amusing research (if it were not for the seriousness of the matter). It was that research had shown (indeed has known for a long time) that alcohol intoxication effects thought processes significantly more than reactions (reactions are still effected!). The upshot was if a drunk approaching a difficult manoeuvre, lets say a sharp bend, and he took it slowly “carefully thinking” about it, he was more likely crash than if he took it faster and so his thought processes where switched to less conscious reactive responses. (However I must stress that no one is suggesting – well not me at least - its ok to drive drunk as long as you go like a bat out of hell!!).

I have in fact tried this mildly intoxicated on a road where 50mph would seem safe and indeed at 80mph you do feel more in control!

So it would seem as well as the loss of inhibition that makes a drunk driver go too fast, in fact, his loss of inhibition is reinforced by his experience of feeling safer, because he is “safer”.

So what I am wondering is will we see speeding drunk drivers trying to mitigate their speed on the basis of scientific study showing that a speeding drunk is safer than a slow drunk? Perverse but true!

Ed_m: I do appologise it was in fact it was Roger who said on Tue Feb 03, 2009 22:46
“Actually I think Lucy is right. “

Again I apologise for misappropriating these words of wisdom to yourself.

thank you
i assumed it was something like that.

as i posted previously my reasons for using and my method of driving with CC means that the difference between the two (if any) doesn't really concern me.
i guess if i'm given reason for concern then i'm covering the brake not the throttle in most instances (unless the most likely response is to blip the throttle in which case i'll be covering that).

That’s irrelevant. We’re debating the difference of reaction to an emergency from what are effectively two outcomes of a prior choice.


Aren’t these in direct contradiction? How come we can’t override a choice if we have no control how we react?


A choice in a spontaneous reaction – seriously?



Only if one participant has a closed mind.
While I obviously agree that having the foot hover is usually a choice reaction, I don’t understand why a subsequent spontaneous reaction (edit) would be one of choice (especially as you stated: “If a pedestrian steps in front of me I can not stop myself braking and steering to avoid a collision.”), or take any longer to mentally process.


A decision is not a spontaneous reaction, hence that comment is false anyway.

Until an explanation has been given there is no reason why the view of spontaneous over-riding choice shouldn’t be accepted; so how can it not be so? Yes you’ve said it can’t but what I’m asking is why?


I thought this is what we were talking about. So is choosing to hover (same as feathering but without touching the pedal) that anticipation? If not then what exactly is the difference?


Should that be of concern?



I’ve had a look. I have to say I’m not sure which point Roger’s comment was relating to (I also agree with the first of the two points within your prior post). Furthermore, I infer the rest of his post to be extolling the virtues of hovering – please do correct me if I’m wrong Roger.

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Views expressed are personal opinions and are not necessarily shared by the Safe Speed campaign

I've yet to read anything that suggests to me why I should rest my right foot anywhere else than over the brake while on CC.

1. If I'm using CC, I'm going as fast as I would wish to, so I'm far, far more likely to need the brake than the throttle.

2. To place my foot elsewhere just because having my foot over the brake is apparently unnatural and according to someone else I'm unable to treat braking from that position as a spontaneous act? How can someone else determine whether an act comes naturally to me or not? It comes perfectly naturally to me; by the "not spontaneous" argument I'd randomly apply the clutch when I had to brake in an emergency, lol.

3. And I don't use this foot position as a justification for driving faster than I otherwise would, just as a technique in my 'tool box' - if I'm allowed to use that term as well.

To be honest Steve, I have no idea what you are debating now. I thought it was the time difference between a choice reaction and a spontaneous reaction.

Sadly, you are confusing the post but putting you own interpretation on reactions and decisions, making out that a choice reaction is a decision due to being unfamiliar with the terminology. And now other people seem confused.

Nevertheless, I don’t know what you do for a living but I am sure you know what you are talking about in that area of knowledge.

As I said in my response to Claire “I feel that I must now close the debate on this particular Cruise Control braking scenario as I feel that I am repeating myself and have nothing else to add.” But don’t let that stop you reading my posts carefully and trying to understand them. If there are any sensible questions I will gladly answer them.

I did say in my first post in this sub-debate “The science of braking is a complicated one” and so it would seem that a Safe Speed thread is not the place to tackle complicated technical and scientific matters.

And should my intoxication be of concern? I don’t know. It’s pretty common place round here, just as smoking in our pubs and hunting foxes with hounds. You may have seen the new thread “10 mins of madness” – Salopians are a bit of wild bunch!

This reminds me of a good joke.

A driver was pootling along a motorway when he hears an urgent traffic bulletin on the radio. The broadcaster announces:
"There is a vehicle being driven on the wrong side on the M1 motorway"

To which our driver thinks to himself:

"Hey, that's the road I'm on. There isn't 'one' driver on the wrong side - there are hundreds of them".


Anyway, it seems between us we have indeed reached some sort of impasse. However, I would like this very simple question answered:


So is choosing to hover (same as feathering but without touching the pedal) that same anticipation? If not then what exactly is the difference?

_________________
Views expressed are personal opinions and are not necessarily shared by the Safe Speed campaign