Safe Speed Forums

MM came up with an article based on MCN article - measuring drivers eye vision to see where they looked.

Now - there are some computer experts in here who might like to put things in perspective , but based on my experience and that article , i have an idea of things going on in the human brain , if compared to a cpu, and there is a striking similarity.


A cpu/OS hs only a finite number of IRQ - some are shared -


In driving - various IRQ are engaged in a subconsious search for external stimuli - some for hazards, some to drive/sterer /change gear / some for speed cams - problem is how many do we have and what happens when all are fully utilised .Do more experienced /older drivers suddenly gain more or start to be able to share more ??

That is the question ??


Any suggastions.

_________________
lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on

Nice one

I think that the IRQ count and efficiency increases as one - by practice and reruns (such as "near miss") commits more process to the lizard brain from the subconscious brain - so that more happens in co-processors accessed via pipeline burst cache from the main brain. Howzat?

Like it - was just an attempt to see how much info the human processer could handle before errors set in - but computing is very much a sideline of mine - understanding the total process would take more processing time than i'm prepared to give

_________________
lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on

This has been discussed a couple of months (or perhaps four months) ago, probably in here. Paul kicked something off. Do a search on "lizard brain". It developed quite well I think.

The basic premise was to commute as much from the conscious to the subconscious as possible and in turn as much from the subconscious to the lizard brain (breathing is a primary example of that - it is autonomic and happens as a totally background task). This gives the capacity for better handling of almost anything one does.

Roger - know that one - this was an aside to that one - Paul's one was of the brain doing thngs on a sub routine - i am asking if it is more of IRQ time - run set functions , irq to see if anythinfg is needed/ program is halted if any additional info is input etc.
Looking more at ability to halt running programs and divert if/when needed to more impotrtant tasks

_________________
lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on

It's called "cognitive recoding". This is something on which George A. Miller et al. did a lot of research in the latter half of the last century. The basic theory is that humans can handle a finite number of "chunks" of information at once. So, for example, when learning to drive a learner might have to handle the following chunks for a gear change:

1. Lift right foot from accelerator;
2. depress clutch pedal;
3. move gear lever to centre and then into position corresponding to required gear;
4. smoothly release clutch pedal while;
5. increasing pressure on accelerator to maintain smooth progress.

That's 5 chunks.

It might surprise to know that most humans have a capacity to handle between five and nine chunks only in immediate conciousness (which is where the "rule" of 7 +/- 2 comes from). So, for our learner, a simple gear change has taken over half her available immediate conciousness. However, for an experienced driver each gear change is automatic; the gear change procedure has become recoded to a single step at a higher level.

I'm convinced that the same thing happens with road safety. You learn to recognise dangerous situations. At first, each of several factors take one of your immediate conciousness "slots". While you can cope, you will have fewer spare "slots" and so your concentration will be like tunnel vision. Once you've experienced a similar scenario enough times, you will automatically recognise the danger - you will have recoded the various factors to one chunk and so will have more available "slots" and thus be able to take in more of the periphery.

Now, by dumbing down road safety the authorities are not allowing drivers the opportunity to recode the driving experience, thus forcing them to operate at a lower level and denying them the chance to acquire the skills that might one day save their lives.

JMHO...

_________________
Will

Ok. One (possible) example - and I'm fairly sure I've not put this in public forum before.

Some years ago I was doing a serious amount of driving - 120 miles each way each night after a day's work to snatch 20 minutes with each of my parents individually in separate wards of the same hospital, both in for entirely different purposes. My (then) vehicle, a Honda Accord 2.2 4WS with speed-sensitive power steering - assistance is 100% when parking and turns progressively down from a certain speed (20 mph I think) upwards, such that no assist is given from 50mph upward.

On one journey homeward, the speedo went erratic and then read zero. I was on the motorway doing approx 69.999 mph. A few moments later the engine warning light came on. I cast my mind back to the shop manual (still driving at approx 69.999) and remembered that one of the feedback loops in the engine management system was from the road speed sensor, put these two down to the same fault, decided matters were of no consequence and kept going.

I got to a sweeping left-hand bend on the motorway, gently pulled the wheel with my left hand, relaxing with my right - and it moved VERY easily. My lizard brain wanted to tug it harder and further to get a response from the road/wheel grip, with my right hand being ready to catch the viscious return slide that would doubtless ensue when it finally got a grip. somewhere though the other half of my brain put two and two together and realised that the zero reading speedo had kicked in the power assist to full. My right hand listened to that part of my brain, while my left hand was trying to overrule it. the result was that both my hands pulled very hard downwards on their respective sides, compensdating for one another in an ever-increasing manner until the NMIRQ got listened to fully, whereupon I went around the bend without incident, relying fully on the mecahnics, with absolutely no feedback whatsoever from the wheel.

I had fairly serious bicep muscle ache from this when I got home - and I wouldn't be surprised if the steering column tilt mecahnism hadn't been stressed close to its design limit (but it showed no signs of strees).

Does the above four-year-old drama nudge this thread any further forward?

Intuitive right brain controlling left hand.

Logical/analytical left contolling right hand.

Would this have happened similarly on a right hand bend?

Seperate interupts for each side/section of the brain possibly?

I have wondered this many times - if a decent right hand bend had come first, would I simply have got it right, simply have got it wrong with panic and crashed big time, or would I actually have gripped and pushed UPWARD with both hands in the left/right conflict for those few tenths of a second.

It actually took a bit of courage for me to post this, with a minor concern at being labelled a crank or "split personality"

Going off on a bit of a tangent here but this thread explains nicely why mobile phones and driving are generally a bad idea, but why some experienced drivers won't have any problem in using them.

I suppose the holy grail of all this is to get the entire process of vehicle control into a single autonomous chunk that you can send simple commands to like "avoid that falling rock" and it just happens.

That leaves you with plenty of room to look out for the hazards and maybe one or two spare for that ham sandwich or phone call

Of course cams are going to take up two chunks minimum, one is a monitoring process that keeps track of the current speed limit as the signs change and another monitoring the actual numerical speed.

However, as I said in the other thread, these work in a completely different mode to driving. They work in the logical mode rather than the intuitive mode, so I suppose the ultimate question is can these two work simultaneously (as in a CPU and a maths co-pro) or does it have to switch modes (as in between segmented addressing and 32bit addressing) with the associated data corruption that can occur if you get it wrong.

If they can work simultaneously, what is the bus overhead between them, are the two halves of the brain communicating across the 33mhz PCI bus or do we have HyperTransport?

Continuing the analogy to absurd lengths, I'd say that the brain's two halves are like an CPU+AMD760 northbridge (the logical part) and a VIA 686B southbridge (the intuitive part) communicating over PCI with the 686B able to interrupt the northbridge and CPU for as long as is necessary, controlling the resources directly via DMA. Putting cameras on the road is like installing a SoundBlaster Live 5.1 card in there, at which point it gobbles up huge amounts of PCI bus bandwidth[1] and causes data corruption if you're accessing your harddrive at the same time.

And if anyone actually follows that analogy and understands it completely I'll be amazed!

[1] admittedly a significant part of this well-known problem was caused by bad drivers *ba-dum-tsch*

I would say the camera issue takes up 3 chunks. Monitoring current limit, monitoring speedo and then looking for cameras / feedback loop of 'did it flash'. Which if in the worst case you are a person that can keep 5 thoughts going at once then it doesn't leave you much head space for anything else.

The analogy sort of works for me. You'd also get deadlock when all the interrupts are fighting over the same resource.

I see it more like a cyclic buffer working in an event driven program. Thoughts about the road ahead pop in at one end and pop out the other when you have passed them. You may have a multi headed buffer so you can keep multiple thoughts going and pop them off the buffer once you have dealt with them. Each thought would generate an interrupt and you'd have to go and process it with another subroutine. Interrupts could be passed to a stack so you could have more than one going at once. Problems occur when your stack space is full! Meanwhile there are a few other loops going on that add things into the buffer such as 'what speed am I doing' at regular intervals. At some point you can't keep all those thoughts going at once and things either drop off or you need a reboot You'd have your car control loop, hazard perception loop, road signage/ lane markings etc loop, navigation loop, speed/camera monitoring loops and probably one or two more like 'what shall I have for tea' or other thought processes that happen while driving along. It has to be a multi threaded system. Some take more processing time than others. Ideally the car control loop should be a background process which doesn't really interfere with any of the other higher level processes. When you first learn then it does take more processing power to control the car, after a while you don't have to consciously think about what exactly you are doing. I suppose technically it would be the lizard brain loop

Mobile phones and other things are just another loop. If you have the spare mental capacity then it should be ok but I don't think it is for most people most of the time.

I go into Blue screen and GPF mode = and I think I would crash - if I tried to hold a conversation on a phone - hands-free and legal - when ANY hazard density above negligible exists.

Roger - never have any problems with phone - but then , most of my life i've done a job that demands that i hold corded phone between head and shoulder, listening to information coming in and making tests/adjustments with my free hand(s) ---perhaps for me it's become a part of my way of life .

When i strted this off i had ideas of

Start off - all functions given over to examination of hazards - all IRQ locked out.
Take away , change up, done by lizard brain under control of an IRQ, firther IRQ being allowed to become active as drive progressed, one IRQ being dominant and constantly seeking out hazards, other IRQ running subroutines in background.(speed/gear /indicators etc.

What has become obvious is that perhaps gong for a drive is more like a basic program , with the lizard brain running in the background and other subroutines being called into play as/when required , perhaps by interupts , and one huge sensor ready to trigger an IRQ , to call into action a subroutine to overide basic driving behaviour and trigger a self preservation mode - to take evasive action etc -

Thats my thoughts from the input - Paul - any more ideas ??

_________________
lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on

I have noticed myself, not just when driving, initiating an instinctive reaction then suppressing or amending the actual physical response with a logical/analytical reaction. So if you are split then so am I.

I think I gain an extra three chunks in a well behaved aircon car.

I loose a couple of chunks when there are speed cameras around or a driver on my boot lid.
A cyclist cycling on a reconised path uses two chunks and a cyclist on the wrong side of the road or without lights takes about 4 chunks

gear changing and sterering is so automated it takes 1-2 chunks
initiating a phone call might take 2-3 but continuing a call 1 chunk.

Hampshires off-piste road designs often take 3-4 chunks as iI try to anticipate how others will tackle thier obsticle courses and signs..

It feals lik a lot of processes go from the senses to the limbs without using the brain. such as cornering. Where as seeing a cyclist needs some processing to presict what happens next and where do I want to go.

_________________
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