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Old 31st January 2013, 21:19   #91
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Re: Things they don’t teach you at an Indian driving school

Vivek, this is interesting discussion.

The way I look at it is like this. In case of a crash, damage suffered is because of the object's inability to dissipate/transfer the energy that it receives. Assuming all other things being equal, the car on the receiving end (one being rear-ended) is getting same amount of energy transferred in both scenarios. In the "release brake at last moment" scenario, some of this energy would get spent on pushing and moving the car forward. The remaining energy is the one that would cause the damage to the car being rear-ended.

In both the scenarios, the crumple-zone of the car being rear-ended is absorbing the same amount of energy and pass the rest to the passenger cabin. In "release brake at last moment" scenario, since some energy is already spent in moving the car, the "crushing" energy is smaller and since the crumple-zone absorbs same amount of energy in both scenarios, the energy passed onto the passenger cabin would be smaller in "release brake at last moment" scenario.

Last edited by SDP : 31st January 2013 at 21:22.
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Old 31st January 2013, 21:29   #92
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Re: Things they don’t teach you at an Indian driving school

Quote:
In "release brake at last moment" scenario, since some energy is already spent in moving the car, the "crushing" energy is smaller and since the crumple-zone absorbs same amount of energy in both scenarios, the energy passed onto the passenger cabin would be smaller in "release brake at last moment" scenario.
you are speaking of "since some energy is already spent in moving the car" as if it's immaterial. Actually, this is the one that's throwing you around as a passenger and causing a whiplash. And this IS passed to the passenger in terms of kinetic energy (motion).
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Old 31st January 2013, 22:13   #93
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Re: Things they don’t teach you at an Indian driving school

^^ Very valid point!

In case of rear-ending, wouldn't one get pushed "into" the seat because of the impact? If the headrest is positioned correctly, the neck should not break because of bending backwards. So what are we missing?

Another angle: when there is no movement (or lesser movement) of the car (because of driver's foot on the brake), would the G forces (experienced by the driver) be higher because the time over the impact is spread is lesser as compared to when you allow the car to move a bit by taking your foot off the brake?

EDIT: Enough physics for today (time to go to bed). Thanks for the refreshing discussion. Would read up more tomorrow.

Last edited by SDP : 31st January 2013 at 22:16.
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Old 31st January 2013, 22:29   #94
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Re: Things they don’t teach you at an Indian driving school

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Originally Posted by SDP View Post
^^ Very valid point!

In case of rear-ending, wouldn't one get pushed "into" the seat because of the impact? If the headrest is positioned correctly, the neck should not break because of bending backwards. So what are we missing?
it's a safeguard that we hope works. If it always worked, we will not be having this discussion.


Quote:
Another angle: when there is no movement (or lesser movement) of the car (because of driver's foot on the brake), would the G forces (experienced by the driver) be higher because the time over the impact is spread is lesser as compared to when you allow the car to move a bit by taking your foot off the brake?
no, the impact on the car will be made more severe by the shorter time. The impact on the driver will be measured by the residual (kinetic) energy divided by the time. Lesser the movement, lesser the impact. in ideal case, no movement, no impact. The car will bear the brunt.

EDIT: one more point I have forgotten to discus (since I have a pretty large minivan), is if you have a small car (relative to the vehicle hitting you), and passengers in rear seat, you might prefer a movement as opposed to complete destruction of the rear portion of the car, for obvious reasons. The preference should be no-injury>whiplash> bad physical injury.

Last edited by vivekiny2k : 31st January 2013 at 22:33.
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Old 1st February 2013, 00:21   #95
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Re: Things they don’t teach you at an Indian driving school

Quote:
Originally Posted by vivekiny2k View Post
You are mixing up "car rolling forward" with "car staying still with brakes released".
I found one discussion that supports my theory
http://cr4.globalspec.com/thread/653...Auto-Collision
more discussions here.
http://ask.metafilter.com/18758/Rear...best-practices
Car will roll forward anyway on impact, when brakes are off.
Your links are interesting. Thanks for putting them up. I think I've drawn my own conclusions, wherein

1. If I have the bigger vehicle than the one rear-ending me, I'd minimize damage to its rear end by releasing the brakes and even rolling forward a bit (in any case, I usually stop with a big gap from the car ahead).

2 .If I am in a car that's smaller than the one rear-ending mine, I would rather release the brakes and let my front bumper take the impact, than making my car nosedive under the car in front and have its rear bumper in my windscreen, and no airbag being deployed.
Quote:
Originally Posted by vivekiny2k View Post
...one more point I have forgotten to discus (since I have a pretty large minivan), is if you have a small car (relative to the vehicle hitting you), and passengers in rear seat, you might prefer a movement as opposed to complete destruction of the rear portion of the car, for obvious reasons. The preference should be no-injury>whiplash> bad physical injury.
You said it!
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Old 5th February 2013, 15:40   #96
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Re: Things they don’t teach you at an Indian driving school

SDP, great thread!

What these schools teach is to hold the wheel and keep the car straight and nothing else. they themselves may not have any clue about the traffic rules and most of these instructors are not trained and they take up this job on a part-time/temporary basis..

they take the "learners" to a crowded-narrow road and ask them to drive, without giving any heed to the people trying to overtake/honk, infact am not surprised when i see a car with "L" board driving at his own pace on the middle/right lane. as he will be just following what he was taught at the driving school...

To tackle this, the authorities should give permission to only those schools which has wel trained instructors, cars in good condition and also develop a curriculum which consists Dos and Donts. it should be made mandatory for every learner.
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Old 5th February 2013, 16:05   #97
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Someone suggested this post on the Bangalore traffic police Facebook page.
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Old 5th February 2013, 16:18   #98
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Re: Things they don’t teach you at an Indian driving school

this thread has just been shared on Bangalore Traffic Police's Facebook page!!



thanks SDP!
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Old 5th February 2013, 17:03   #99
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Re: Things they don’t teach you at an Indian driving school

Quote:
Originally Posted by pratap.pratu View Post
Dear SDP and Team BHP Owners,
Regarding SDP's post on driving experience which he has very nicely presented, can i share the thread with Bangalore traffic police on Facebook ? Hopefully its going to increase awareness or refresh for few just like what I felt after going through your post and prevent accidents or increase safety. We need permission from you and also equally from Team BHP owners on this share. I shall copy paste the link to Bangalore traffic police and let them how important this is from my end.
Please let me know your opinion and correct me if am wrong since this is my first step and first post in team bhp after I have enrolled in this wonderful community.

fyi :
the link that i came across was
http://www.team-bhp.com/forum/street...ng-school.html

Regards,
Pratap
Quote:
Originally Posted by Wheeliej View Post
Someone suggested this post on the Bangalore traffic police Facebook page.
Quote:
Originally Posted by IronH4WK View Post
this thread has just been shared on Bangalore Traffic Police's Facebook page!!



thanks SDP!
Looks like fellow TBHPian Pratap did it! Thanks Pratap.
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Old 5th February 2013, 22:07   #100
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Re: Things they don’t teach you at an Indian driving school

Hi Guys,
As shared above by SDP, Bangalore traffic police shared the article from SDP and everybody has posted and responded only positive reviews on the article..Honestly wanna contribute and support our fellow cops with such articles and spread awareness...Thanks SDP and teambhp owners for this to work..
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Old 5th February 2013, 22:14   #101
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Re: Things they don’t teach you at an Indian driving school

Awesome effort!

But you know what I feel? Most folks on t-bhp already know most of these rules. And those bad drivers like cabbies, autos are not on t-bhp. How do you educate them on these rules?
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Old 6th February 2013, 08:40   #102
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Re: Things they don’t teach you at an Indian driving school

The Bangalore Traffic Police FB page has 2 very good comments in reaction to this thread:

Things they don’t teach you at an Indian driving school-bangalore-btp-comments.png

About the first comment, I think, sarcasm mixed with some humor might work. At the same time, if it is taken in the wrong way may lead to road-rage.

The second comment, the one by Rohan Shirodkar, is beautiful. I have always wondered why we are the way we are and that comment provides a very good answer.
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Old 11th February 2013, 22:22   #103
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Re: Things they don’t teach you at an Indian driving school

@blue_pulsar : The answer to your question lies with little effort from our fellow Bangalore traffic police community in my opinion by the following way.
Just like the way the bus drivers are taught on safe driving at BTP HQ (Which goes about very frequently), similarly meetings must be held in a organised fashion for every autos starting with each RTO division.. It might be cumbersome but atleast 50% of those auto drivers might get some sense into how to make roads much safer and nice to drive. Same initiative must happen with Cabs and Cab owners whichever is feasible. The effort must be made though and it is a matter of time when people appreciate what this is all about...
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Old 13th February 2013, 13:25   #104
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Very nicely compiled piece of work SDP. Thanks a lot for collating all the info from the many threads and banging it onto one single thread.

Very helpful indeed
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Old 13th February 2013, 17:12   #105
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Great one SDP. Was this part of the core work that you have been reporting in a separate thread?
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