Safe Speed Forums

I had my parents over at the weekend so I decided to take them for a drive to visit some of the local scenery. My mum normally insists on driving everywhere due to suffering motion sickness, but after getting into a car with her earlier in the year for the first time since I've been driving I decided that I didn't really want to repeat the experience.

(It didn't help that she insisted on sitting in the back of my car. )

I drove along a road that I know well as its part of my daily commute, and knowing that I had a carsick passenger on board I was taking it easier than normal - slowing down much more for corners and trying to avoid some of the lumpier sections of tarmac. When we arrived my dad made a little comment about me 'not really driving for my passengers'. I must admit that I was a little bit offended by the comment, so when my parents were out of earshot I asked my partner, who was also in the car, what he thought my dad had meant.

My partner replied that I drove like I knew the road and went on to explain that being a passenger you tend to notice bumps and corners more - when you're driving you are concentrating on the road to the extent that you don't consciously notice the odd bit of body roll or suspension movement.

So my question is, what can I do to make life more comfortable for my passengers short of rounding every corner at 10mph and driving everywhere at 45mph? This isn't the best road in the world for surface condition and flatness, so was my old man just being fussy after too many years of not being a passenger?

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Science won over religion when they started installing lightning rods on churches.

Sounds like you were doing the right thing. I guess the brief is the same as for nervous/first time pillions; super smooth machine control, choose good smooth lines and avoid sub 10 sec standing qtrs.

You need feedback, Sixy.

I'm quite happy to adapt my style to suit the comfort or interests of passengers, so when I have an unfamiliar passenger I ask a few key questions:

- Are you comfortable at these speeds?
- Is this smooth enough for you?

And then make a judgement based on the nature of the answers. Often it isn't the words that count!

If passengers seem nervous, I find it helps a great deal to talk about some of the decisions I'm making.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

the wrist travel bands work for a lot of people. All they do is put a little preasure on the insideof the wrist. I don't know why they work but they do!

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Speed limit sign radio interview. TV Snap Unhappy
“It has never been the rule in this country – I hope it never will be - that suspected criminal offences must automatically be the subject of prosecution” He added that there should be a prosecution: “wherever it appears that the offence or the circumstances of its commission is or are of such a character that a prosecution in respect thereof is required in the public interest”
This approach has been endorsed by Attorney General ever since 1951. CPS Code

My wife used to tell me that I drove for myself rather than my passengers. She's a pretty good minibus driver so I asked her how she'd driver for her passengers and listened to her instructions.

In a nutshell, you can't do much about the road surface except pick the best line. WRT corners etc., the trick is to make no sudden changes of direction or speed. Smoothly increase steering input on the way into a bend, try to hold a constant input around the bend, and smoothly straighten out on exit. Passengers can tolerate relatively large accelerative forces provided you apply them gradually. Most of the rest of what she taught me is covered by COAST.

After listening to my wife, I'm now much smoother and get some extra mpg to boot! If your local minibus instructors are as good as the guys who taught my wife, it might be worthwhile doing a minibus course even if you have no intention of ever driving one for real!

ATB & HTH,

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Will

If someone is very sensitive to motion sickness there is not a lot you can do. I used to suffer very badly until I started driving and now my daughers have inherited it. The eldest one was sick travelling along the M4 at constant speed .

The travel bands do seem to help although I don't know how. It is probably psychological, but who cares - I'd try anything not to have to clean up the mess when they are sick.

The furthest we seem to get is about 20 miles before one of them is sick and it doesn't matter whether it's me or my wife driving.

Sounds like you were doing the right thing. I guess the brief is the same as for nervous/first time pillions; super smooth machine control, choose good smooth lines and avoid sub 10 sec standing qtrs.

I have several driving 'modes' depending on the passengers carried.

If just me & the missus I can pretty much do anything except powerslides (or crashing) & she's happy enough as she trusts my judgement. If she feels nervous, (narrow country lanes) she'll say.
With some of my friends I can 'play' a little - it's not a comfy ride, but it will be quick.
Then there's the 'in-laws' and 'virgin' passengers - nice and easy acceleration & braking with just the odd quick take-off thrown in for my personal amusement.

Of course when the grandparents or the elderly are in transit, silky-smooth limo-driver. Second gear take-offs, big long clutch cycles, rev matching, basically the works. No sudden movements, no sudden acceleration and slowing/braking begins really, really early.

Although I'm a speed freak at heart, (NO way do I take risks like blind corners or making other drivers brake for me). I happily adjust my dring style to suit either the passengers or the conditions. Country roads (take me home ) Don't you just love 'em.

Yes, rate of change of acceleration is called 'jerk' and with good reason. Low jerk is good for passengers - much more so than low g.

Low jerk also leads to a strong smooth driving style.

But I have found some passengers sensitive to g as well.

One level more complex is 'jounce' or rate of change of jerk. The smoothest drivers apply low jounce also.

Think of the terms like this:

Speed = rate of change of position
Acceleration = rate of change of speed
Jerk = rate of change of acceleration
Jounce = rate of change of jerk

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Sometimes criticism like this can be a bit unfair. If a passenger is used to a large, quiet, comfy, softly sprung car with a big engine and smooth auto box then a firmer, swifter, manual car is always going to be less smooth unless you are a particularly good driver (which I'm not). I also find that driving differently to your own normal style can sometimes feel unnatural and may contribute to passengers feeling something isn't quite right. Increased self consciousness can impact on your planning and you might see things a little bit later or over-correct etc.

A mate of mine once criticised my gear changes as not being smooth enough. He was probably right, however in my Alfa 156, smooth gear changes are harder than in his Golf. The drivetrain is just different.

Didn't stop me trying to drive the thing better though, so in many ways I'm glad of the criticism.

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"Not everything that counts can be counted, and not everything that can be counted counts."

I don't mind constructive critisism from someone I trust. My mum is one of the worst drivers I know and to an extent my dad just agrees with her because it makes his life easy.

Yes, they both drive much larger cars than I do and I don't suppose the suspension on the rover is anything too special either.

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Science won over religion when they started installing lightning rods on churches.

Get a big ashtray (or shallow bowl or similar) and blu-tack it to the top of the dashboard. Get a ping pong ball and put it in the ashtray then go for a drive...

You can do a similar thing with a glass of water but it's messier!

Anticipation seems to be the key in smooth driving - no sudden changes of speed or direction.

My feeling is that different people get car-sick under different stimuli. With me, it's sharp, repeated braking rather than acceleration, bumps or cornering but I bet everyone is different. I get terribly car-sick if I'm trying to read a map as a passenger. It only takes a few minutes too. I remember once trying to navigate for a mate on a scatter rally - I think I was about a stone lighter by the end of it! Not being able to see where I'm going is also a big contributing factor. Having the right car for the job helps too - as has been said. I used to have a big Citroen DS (The old "Day of the Jackall" ones) and that was brilliant as long as I drove it smoothly. It had a great sprung-to-unsprung mass ratio and would steam-roller bumps out. Lots of people said they used to get sick in big Citroens but I've always found them brilliant if driven correctly!

If all else fails, I'm told by some sailors that sweet porridge with whisky in it is good. Apparently it doesn't cure sea sickness but is the only stuff that tastes the same coming back as it did going down!

That method will help you get low g - but it won't help much in getting low jerk, and most will regard low jerk as more important.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

I thought "jerk" and "G" were one and the same thing? Aren't they both a change in velocity with respect to time?

I'm guessing that 'low jerk' has to do with the acceleration curve & related lift-off. eg. Rapid acceleration (high g) then lifting completely results in the passenger being throw back into the seat & then slung slightly forward. As opposed to a gentler acceration to 'ease' the pasenger into the seat / allow for natural bracing and then push high g (like a car with a BIG turbo), with a slow lift-off & return to normal.

An (even subconsciously) braced passenger can sustain much higher g rates & changes in direction that a relaxed one. Most people want relaxed passengers - so 'easing' them into and out of a high g turn or acceleration makes for a more comfortable ride with less radical changes in direction although the actual g rate may peak at the same point.

Well, that's my understanding of it anyway.

Nope. See my post above: http://www.safespeed.org.uk/forum/viewt ... 7558#87558

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

Any passenger of mine is free to catch a bus instead if they prefer.

And that sums it up really, I've been told my present car makes my pssengers feel "so much safer" than my old car. my current car is an offroad people carrier thats probably pretty coachlike for a passenger- comfortable, quiet and detatched but as a driver you're acutely aware that you need 3 times the braking distance, can't swerve etc if need be like I could in my old scirocco, which made the same people nervous.

Passengers often aren't the best critics.

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Fear is a weapon of mass distraction

Hmmm!

I've never heard the term "jounce" used like that before. Americans tend to use it to mean a compression of the springs. They talk about "jounce buffers" rather than bump stops. That said, I did a quick search for it and wikipedia does define it as the fourth derivative of distance with respect to time which is the same as what Paul's saying.

I suppose you could get very small but irritating accelerations which would leave the ball in the ash tray because of its own inertia. A bit like if you picked the ash tray up and shook it from side to side quickly so that before the ball could roll to the side and pop out, the ash tray would be moving the opposite way.

Is that what you mean?

I gave up chauffeuring my parents anywhere, because when they were in the car I would attempt to make my driving slower and more passenger-friendly than usual - then at the end of the journey I would be told off for driving too fast!

After discussing it we came to the conclusion that being older, their reaction times were slower, and they were comparing my driving to what they would be doing in the same situation, and they simply didn't feel comfortable with higher speeds and shorter braking distances than they were used to, however smooth or technically proficient. So these days, if my mum is in the car, my dad drives, and at least he is still perfectly safe, if not exactly Jenson Button.

If I'm with work colleagues and people closer to my own age group (in their 30s-40s) I generally get positive feedback on my driving, and I don't make any particular concessions, though I do avoid gratuitous use of horsepower for fun.

I find that most younger drivers I ever ride with, say 30 to 45 age group, are much slower on twisty roads than I am, but tend to cruise faster on dual carriageways, thus putting themselves in danger of being 'scammed'.