/ Crash: I didn't see you.

This topic has been archived, and won't accept reply postings.
lowersharpnose - on 17 Oct 2013
This quick demo shows why when a driver says 'I didn't see you' he is telling the truth.

I found it very revealing just how quickly my peripheral vision disappeared.

http://www.msf-usa.org/motion.html

butteredfrog - on 17 Oct 2013
In reply to lowersharpnose:

Wow! Its quite shocking actually.
MG - on 17 Oct 2013
In reply to lowersharpnose: Fascinating. Thanks.
teflonpete - on 17 Oct 2013
In reply to lowersharpnose:

Wow, that is revealing, and I've always had a vested interest in the "didn't see you" excuse as I'm a motorcyclist.

I tried making the dots larger and playing around with the background colour and it still happens.
MG - on 17 Oct 2013
In reply to teflonpete: They were still disappearing at a size of 35 for me!!
Neil Williams - on 17 Oct 2013
In reply to lowersharpnose:

That's quite scary. Perhaps something that should be included in the driving theory test (as it's electronic now) or hazard perception to highlight it?

Neil
Offwidth - on 17 Oct 2013
In reply to lowersharpnose:

Really nice demo. Most people are under the impression that what we see is real when in fact the brain makes a good deal of it up to speed up our response to visual stimuli (that might once have kept us alive).
MG - on 17 Oct 2013
In reply to Neil Williams: It would be interesting if someone could set it up to work with the central blob was say a pedestrian on a crossing, the external ones as children on the pavement and the moving background a typical urban landscape.
johncoxmysteriously - on 17 Oct 2013
In reply to lowersharpnose:

Interesting; thanks.

Though mind you I've always believed drivers who say 'I didn't see you'. It seems inherently more probable than 'I did see you but I decided to drive into you anyway'.

jcm
teflonpete - on 17 Oct 2013
In reply to johncoxmysteriously:
> (In reply to lowersharpnose)
>
> Interesting; thanks.
>
> Though mind you I've always believed drivers who say 'I didn't see you'. It seems inherently more probable than 'I did see you but I decided to drive into you anyway'.

But you have to separate "Didn't see" from "Didn't look".
ByEek - on 17 Oct 2013
In reply to teflonpete:

> Wow, that is revealing, and I've always had a vested interest in the "didn't see you" excuse as I'm a motorcyclist.

Agreed. Unfortunately, the a-hole learner motorcyclists weaving through the traffic this morning was unfortunate to be hit by a Land Rover who naturally won't have seen him. Didn't stop him hurling (unfounded) abuse at the driver though.
balmybaldwin - on 17 Oct 2013
In reply to lowersharpnose:

Very interesting, but It would be better if the peripheral blobs were moving around, as I think in part the selective vision of the brain relates to movement... i.e. if something is stationary it doesn't matter as much as something that is moving, and of course when driving everything is moving to some extent if you are in motion, or if you are stationary at a junction then the important things are moving (kids crossing roads, cyclist/car/motobike coming along the road you are turning on to etc
Offwidth - on 17 Oct 2013
In reply to balmybaldwin:

I dont think it relates much to bike accidents at junctions, the demo just shows your eye/brain combo can play tricks on you, especially in periferal vision with a fixed focus and a moving field of view. If you stop (reduce the moving field) and look a couple of times (remove the fixed view), as recommended, you will see that bike.
teflonpete - on 17 Oct 2013
In reply to ByEek:
> (In reply to teflonpete)
>
> [...]
>
> Agreed. Unfortunately, the a-hole learner motorcyclists weaving through the traffic this morning was unfortunate to be hit by a Land Rover who naturally won't have seen him. Didn't stop him hurling (unfounded) abuse at the driver though.

Don't get me wrong, there are knobs using all forms of transport and some motorcyclists don't do themselves any favours.

However, after ploughing into the side of a car that turned right across my path (he was oncoming) whilst I had my headlight on and a reflective top, was going through a green traffic light and doing 10 mph under the speed limit, I can only assume the moron didn't even look, let alone "didn't see". If he'd pulled away half a second earlier I'd have broken my neck on the roof of his car rather than summersaulting over his bonnet.
dissonance - on 17 Oct 2013
In reply to Offwidth:

> I dont think it relates much to bike accidents at junctions


Think this has been linked to before but looks at those scenarios.

http://www.londoncyclist.co.uk/raf-pilot-teach-cyclists/
Offwidth - on 17 Oct 2013
In reply to dissonance:

Cheers.

For those that like optical illusions here are a few more:

http://www.bbc.co.uk/science/humanbody/mind/interactives/isseeingbelieving/
richyfenn on 17 Oct 2013
In reply to teflonpete & balmybaldwin:

They're the the reasons I will weave slightly side to side when approaching vehicles waiting to pull across my path, it increases the chances of you being seen as the brain picks up sideways movement far better than something moving straight towards you. Easy on the motorcycle being in the middle of the lane, but can be a bit dangerous on a cycle at the side of the road, but if there are cars along side you no one should pull out anyway (hopefully).
PeterM - on 17 Oct 2013
In reply to lowersharpnose:

A great demo of tunnel vision and not paying attention to your surroundings.
dissonance - on 17 Oct 2013
In reply to Offwidth:

> For those that like optical illusions here are a few more:

Richard Wiseman tends to be a good source for those.

http://richardwiseman.wordpress.com/blog-2/

Trangia - on 17 Oct 2013
In reply to lowersharpnose:

I've often wondered about the "I didn't see you" explanation for motorbike/bike collisions at junctions, and have long felt that it's too common an occurrence to simply be put down to simply driving without due care and attention. I think that reason comes into it but I also think there is more to it than we really understand.

I consider myself to be an alert and sensible driver, but I don't mind admitting that over my driving career I've had a few near misses after which I've pinched myself and wondered why the hell I didn't see the motorbike/bike until nearly too late? How many others of you have experienced this - be honest with yourselves?

I think that because it's so common - I'll bet there isn't a biker or cyclist out there who hasn't experienced vehicles pulling out in front of them? - that it needs more serious research into the reasons and to find solutions.
Guy - on 17 Oct 2013
In reply to lowersharpnose:

Lateral movement is your friend in being seen. If you are on a steady course directly at someone then they will find it harder to see you than if you are moving across their line of sight. So if you see a car in a side road then move out early to give them a change of focus.

Still doesn't help with people who don't look though!
teflonpete - on 17 Oct 2013
In reply to Guy:
> (In reply to lowersharpnose)
>
> Lateral movement is your friend in being seen. If you are on a steady course directly at someone then they will find it harder to see you than if you are moving across their line of sight. So if you see a car in a side road then move out early to give them a change of focus.
>
> Still doesn't help with people who don't look though!

That's what I do on the bike, try and make as much room as possible in front of the car about to pull out and try and put yourself as near as possible to the driver's line of sight when he's looking forward.
hang_about - on 17 Oct 2013
In reply to lowersharpnose:
> This quick demo shows why when a driver says 'I didn't see you' he is telling the truth.

It's the women who mow me down on my way to work normally.
Babika - on 17 Oct 2013
In reply to lowersharpnose:
That's amazing.

Apparently referees develop incredibly good peripheral vision - anyone out there found that they can still see the three yellow dots throughout?
Offwidth - on 17 Oct 2013
In reply to Babika:

"Apparently referees develop incredibly good peripheral vision" How??
Blue Straggler - on 17 Oct 2013
In reply to balmybaldwin:
> (In reply to lowersharpnose)
>
> Very interesting, but It would be better if the peripheral blobs were moving around, as I think in part the selective vision of the brain relates to movement... i.e. if something is stationary it doesn't matter as much as something that is moving, and of course when driving everything is moving to some extent if you are in motion, or if you are stationary at a junction then the important things are moving (kids crossing roads, cyclist/car/motobike coming along the road you are turning on to etc


There is one scenario that you overlooked and which doesn't quite fit into your examples: people stationary at a zebra crossing, waiting to cross. If they are on your side of the road and you are going slow enough that they assume you have seen them and are drawing to a stop, they may just step out. The timing of this sequence may be catastrophic
Babika - on 17 Oct 2013
In reply to Offwidth:

No bloomin idea..

But I just read Per Luigi Collina's autobiography and he said so.

As one of the best referees in the world I guess I just believed him
Offwidth - on 17 Oct 2013
In reply to Trangia: You haven't read the link dissonance provided. Its a good summary of the sort of reasons why it happens which are little to nothing to do with the optical illusion the OP showed (other than the eye brain combination makes stuff up). It also has solutions which amount to what I said above: stop at a junction and look properly twice.
Offwidth - on 17 Oct 2013
In reply to Babika:

Must be true then????
balmybaldwin - on 17 Oct 2013
In reply to Offwidth:
> (In reply to Babika)
>
> "Apparently referees develop incredibly good peripheral vision" How??

By not seeing what's happenning directly in front of their noses?
Babika - on 17 Oct 2013
In reply to Offwidth:
Nah - I expect he just lies to sell more copy.
Definitely the most likely explanation
jkarran - on 17 Oct 2013
In reply to Neil Williams:

> That's quite scary. Perhaps something that should be included in the driving theory test (as it's electronic now) or hazard perception to highlight it?

Better at the instruction stage, get people into the habit of moving their heads around scanning properly at and when approaching junctions.

jk
dissonance - on 17 Oct 2013
In reply to Offwidth:

> "Apparently referees develop incredibly good peripheral vision" How??

Guess they could use the same sort of methods that pilot suggests. So no change to the actual vision but just looking more effectively.
deepsoup - on 17 Oct 2013
In reply to Trangia:
> I consider myself to be an alert and sensible driver, but I don't mind admitting that over my driving career I've had a few near misses after which I've pinched myself and wondered why the hell I didn't see the motorbike/bike until nearly too late? How many others of you have experienced this - be honest with yourselves?

Quite recently, it was very sobering.
Though I wasn't wondering for long why I didn't see the bike until it was nearly too late - I was thinking about a problem I was dealing with at the time and distracted, and realised in hindsight that I simply hadn't looked properly.
Neil Williams - on 17 Oct 2013
In reply to deepsoup:

I have. I think at the time I looked the cyclist was hidden behind the pillar. The lesson is to look at least twice.

Neil
MG - on 17 Oct 2013
In reply to Offwidth:
> (In reply to Trangia) You haven't read the link dissonance provided. Its a good summary of the sort of reasons why it happens which are little to nothing to do with the optical illusion the OP showed

I'm not sure that's right. The link gives a couple of scenarios where a cyclist could remain static in a driver's peripheral vision while the background would "move". That sounds very similar to the link in the OP to me.
Neil Williams - on 17 Oct 2013
In reply to Neil Williams:

(I should clarify I did not hit him, but it was closer than I would have liked)
captain paranoia - on 17 Oct 2013
In reply to johncoxmysteriously:

> It seems inherently more probable than 'I did see you but I decided to drive into you anyway'.

I take it you don't often ride a bike, John... I've had plenty of occasions where a driver has looked right at me, with full eye contact, and then pulled out anyway, knowing I'll have to stop or get injured; "might has right".

Not to mention the "simply didn't look" scenario the teflonpete mentions; I watch drivers, not their car, to see what they might do, so I see when they don't look.

Both situations are rare, but not rare enough.
elsewhere on 17 Oct 2013
In reply to Babika:
> (In reply to lowersharpnose)
> That's amazing.
>
> Apparently referees develop incredibly good peripheral vision - anyone out there found that they can still see the three yellow dots throughout?

Keep blinking or keep your eyes shifting around the image - that seems to work *almost* completely for me.

If the ref keeps moving focusing on different things that should "see everything".

It appears to show that perception of vision is substantially memory with updates for the small areas you focus on.


Trevers - on 17 Oct 2013
In reply to lowersharpnose:

Not sure how this really applies to real life. As a driver, cyclist or anyone, your eyes should be constantly moving, checking, never just fixed on a point (although I often feel some drivers don't notice anything on the road except the 5 meters in front of me).

If the dots moved you'd spot them.
ads.ukclimbing.com
Offwidth - on 17 Oct 2013
In reply to MG:

You'd need to find references on the experiments. Restricted vision and saccadic masking were the main problems of accidents at junctions and roundabouts as I understood it, as the RAF guy in that link said. Motion effects could be an issue in certain circumstances hence my "little".
Offwidth - on 17 Oct 2013
In reply to Offwidth:

Thats obviously for accidents where the driver WAS looking. Not looking I suspect accounts for most cases. It's also depressing how often you see problems where the bike IS seen: the pull out anyway because 'they will slow down OK' attitude or worse still cars playing chicken with bikes in queues to stop them overtaking.
Jim Fraser - on 17 Oct 2013
In reply to lowersharpnose:

A lot of useful stuff is being revealed about the human mind.

One recent study confirmed that the brain does not register or record events continuously. Like a cine camera, your brain is examining discrete frames from amongst the huge volume of data coming down the optic nerve.

Amongst other things, this means that all those cyclists with flashing lights are wasting their time!

You then have to ask what the implications are for direction indicators!

And blue flashing beacons!
Trevers - on 17 Oct 2013
In reply to Offwidth:
> (In reply to Offwidth)
>
> Thats obviously for accidents where the driver WAS looking. Not looking I suspect accounts for most cases. It's also depressing how often you see problems where the bike IS seen: the pull out anyway because 'they will slow down OK' attitude or worse still cars playing chicken with bikes in queues to stop them overtaking.

Often I think it's because some drivers who don't cycle, or have only when they were a child, tend to assume that bikes have a top speed of 5mph, so there's always time.
Offwidth - on 17 Oct 2013
In reply to Jim Fraser:

The 'frame rate' of that camera often isn't an issue but when your moving your head it can be. The flashing lights trigger other psychological cues and they work well.
Offwidth - on 17 Oct 2013
In reply to Trevers: Or they don't assume braking could ever be a problem... or they just dont care. I gave up cycling in my city centre after a lorry driver, who pretty clearly registered me, pulled out anyhow: I grounded the bike on instinct and just missed sliding under the back wheel. 5 minutes earlier I'd nearly gone under a bus when it was overtaking me too tightly on a curve with fence and a wide curb, when approaching a roundabout (I bounced along the fence and got away with it). Cyclists are very vulnerable: a colleague of mine was killed when a pedestrian stepped out in front of him without looking.
Trevers - on 17 Oct 2013
In reply to Offwidth:

Bloody hell, the bus incident sounds scary. I've had one of those Russian-roulette-incidents-with-the-driver-pulling-the-trigger incidents myself being overtaken on a blind corner despite taking the lane. If a car had come round the blind corner towards us, I would have been killed. The stupid f*ckwit then turned off a couple of hundred meters further down the road- if he had waited he would have lost 15 seconds.

But then I've been told that this is what you're accepting when you get on a bike on the road so there's no point getting on your high horse about it.
Jon Stewart - on 17 Oct 2013
In reply to lowersharpnose:

Wonderful illusion, but I don't think it relates to crashes. I think the illusion reveals what the brain's up to under conditions of steady fixation and stationary peripheral objects against a moving background - quite contrived situation.

These types of illusions tend to exist because we don't exist in that kind of visual environment - if we did, we'd be constantly finding ourselves in trouble and evolution would have designed it out.

But I suppose as a take-home message, "your eyes can play tricks on you sometimes" it's tenuously related to road safety.
Jon Stewart - on 17 Oct 2013
In reply to dissonance:
> (In reply to Offwidth)
>
> [...]
>
>
> Think this has been linked to before but looks at those scenarios.
>
> http://www.londoncyclist.co.uk/raf-pilot-teach-cyclists/

Good link. Though I think the original illusion is much more like Troxler fading - an effect of steady fixation which no one should ever, ever experience while driving!
Offwidth - on 17 Oct 2013
In reply to Jon Stewart: Regular light patterns passing in a line at night with a fixed focus straight forward (say on tail lights)...??? I agree its likely not so important on junctions.
Blue Straggler - on 18 Oct 2013
In reply to Offwidth:

There's a straight-to-video film from the twilight of Patrick Swayze's fading career, called "Black Dog", which centres on some driving phenomena (hallucinations experienced at night by sleep-deprived long-haul lorry drivers). The film tacked on some ludicrous thriller plot so I didn't watch it. I'd have been more interested if it were simply about the Black Dog phenomenon!
Offwidth - on 18 Oct 2013
In reply to Blue Straggler:

Well done for getting in an obscure film reference ;-) Not seen it but as I learn more about such phenomena I'm much more concerned than I was with things like driving tired on a motorway that isnt properly lit or entering roundabouts without slowing down a lot.
Blue Straggler - on 18 Oct 2013
In reply to Offwidth:
> (In reply to Blue Straggler)
>
> Well done for getting in an obscure film reference ;-)

Thank you sir. A bit of Googling suggests that black dog apparitions are well established in British folklore, and often reported as night sightings on journeys. This ties in with sleep deprivation and the mind creating detail.
Depending on your search terms, you will also find reports from tired long distance drivers hallucinating the dog (maybe they had seen the movie though!) and truly believing they had hit it.
hang_about - on 18 Oct 2013
In reply to Blue Straggler:
I'd flown back from the States and arrived at Gatwick at 6am. I dropped my brother off at my parents in London and then started driving home along the A1 after a couple of strong coffees. I stopped when I swore I saw a crocodile cross the road. Fell asleep instantly in the layby to be awoken an hour later by a Polish lorry driver reversing over the Ka.
Weird stuff.. Don't drive tired!
Neil Williams - on 18 Oct 2013
In reply to hang_about:

Driving tired would be illegal if they could measure it, IMO.

Neil
lithos on 18 Oct 2013
In reply to Jon Stewart:

+1 with Jon

even more weird shit is the lilac chaser (an example here http://en.wikipedia.org/wiki/Lilac_chaser )

The closest I get to where driving is directly related to visual illusions/examples are
1) motion after effect when driving through tunnels with regularly spaced lights
2) contrast effects with fog.
andic - on 18 Oct 2013
In reply to Blue Straggler:
> (In reply to Offwidth)
>
> There's a straight-to-video film from the twilight of Patrick Swayze's fading career, called "Black Dog", which centres on some driving phenomena (hallucinations experienced at night by sleep-deprived long-haul lorry drivers). The film tacked on some ludicrous thriller plot so I didn't watch it. I'd have been more interested if it were simply about the Black Dog phenomenon!

It had Meatloaf in it as the baddie and a truck chase up a mountain, you should have watched it, you should still watch it!

A few years ago I was doing HGV driving nights. Early in the morning when I was tired post boxes and bushes would become people, it was quite scary.
andic - on 18 Oct 2013
deepsoup - on 18 Oct 2013
In reply to Neil Williams:
> Driving tired would be illegal if they could measure it, IMO.

It is. The Selby rail crash marked a hardening in attitude, if you nod off at the wheel and crash, assuming you survive, you can expect a difficult time with the law.
Jimbo C - on 18 Oct 2013
In reply to lowersharpnose:

The weird thing for me about this little animation is that the yellow dots don't dissapear as much when I've had alcohol. Hmmmm.
ads.ukclimbing.com
lithos on 21 Oct 2013
In reply to Jimbo C:

as does your ability to fixate properly ....
dissonance - on 21 Oct 2013
In reply to deepsoup:
> (In reply to Neil Williams)
> [...]
>
> It is. The Selby rail crash marked a hardening in attitude, if you nod off at the wheel and crash, assuming you survive, you can expect a difficult time with the law.

Its also why HGVs have tachographs.
Neil Williams - on 21 Oct 2013
In reply to dissonance:

True. But the only thing a tachograph proves is that you didn't do too much driving. It doesn't prove that you didn't stay up all night on the piss.

Neil
David Barratt - on 21 Oct 2013
In reply to lowersharpnose: Wow. I had to watch the yellow dots for a while to check it wasn't a trick.
jkarran - on 22 Oct 2013
In reply to Jon Stewart:

> Good link. Though I think the original illusion is much more like Troxler fading - an effect of steady fixation which no one should ever, ever experience while driving!

Shouldn't maybe but it's pretty easy to think of scenarios where you might just fix your gaze on something in front, steady cruising on a motorway for example. Not relevant to cyclists of course but interesting to think your 'blind spots' might be *much* bigger than they appear!

You can very easily fixate like that while flying unless trained to scan carefully.

jk

This topic has been archived, and won't accept reply postings.