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Old 11th July 2013, 15:09   #31
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Default re: Evasive manoeuvres & Rollovers?

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Originally Posted by shankar.balan View Post
The same logic of high centre of gravity and prone-ness to toppling holds good for those Tall Boy cars like the WagonR, the Estilo, the Ritz, the Santro and others, all of whom have tiny short little wheels to boot!
Very true. But since some SUVs have more power than these vehicles, it makes things more dangerous for folks who are stepping up onto these vehicles, or are too enamoured by 'XYZ BHP!' specs.

With greater power comes greater responsibility

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Old 11th July 2013, 15:21   #32
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Default re: Evasive manoeuvres & Rollovers?

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Please understand what lateral acceleration test is and how they are conducted by real reviewers before terming it as destructive testing.
Please understand what I mean by destructive testing before asking me to understand lateral acceleration test.

All car magazine and auto website reviews in India are done by drivers with no professional driving credentials. Some don't even own a car or uncomfortable driving unfamiliar cars. At least some are car enthusiasts and rest are mainly writers. And the tests always happen on regular public roads. In other words, reviewers represent typical drivers on the road.

By lateral acceleration test you are talking about testing the rollover resistance of SUV. If the vehicle rolls-over, it is pretty much destroyed, that is my meaning of destructive testing. If you ask the typical reviewers (me included) to test the rollover resistance, it is beyond the limits of most the reviewers to do it safely. We might end up destroying the vehicle and the manufacturer will ask us to pay for the damages.
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Old 11th July 2013, 15:21   #33
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Default re: Evasive manoeuvres & Rollovers?

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Originally Posted by .anshuman View Post
ESP with Roll over Mitigation is one of the most important safety features when it comes to SUVs with high COG and soft suspension, a feature which most manufacturers conveniently choose to ignore for our market. Obviously it cannot compensate completely for bad handling behavior.
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Similarly, Dacia Duster, the world's cheapest SUV, known as Renault Duster in our market and sold as a premium SUV also has some stability issues. The non ESP equipped it known for scary handling behaviour and even toppling, it also failed the Moose/Elk test somewhere in Europe. No need to guess, ESP is not offered in Indian Duster, not even in the top variant, not even as an option.
Thanks for the post Anshuman. ESP should be a compulsory safety feature for SUVs or similar type of vehicles. Many consider this as the most important safety system after the seat belt. Experts say that ESP can prevent around 80% of skidding /rollover accidents. Unfortunately, in our market majority of the manufacturers give this feature a miss, or some of them keep it on 1-2 variants so that its highlighted as a feature in their brochure.

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Until we get into a stage where safety aids like ESP is made mandatory, drive your car in the way its suppose to be driven, and probably its good to take the warning sign below seriously (Source: (Renault Duster : Official Review))

Evasive manoeuvres & Rollovers?-renaultduster22.jpg
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Old 11th July 2013, 15:28   #34
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Originally Posted by vb-san View Post
Thanks for the post Anshuman. ESP should be a compulsory safety feature for SUVs or similar type of vehicles. Many consider this as the most important safety system after the seat belt. Experts say that ESP can prevent around 80% of skidding /rollover accidents. Unfortunately, in our market majority of the manufacturers give this feature a miss, or some of them keep it on 1-2 variants so that its highlighted as a feature in their brochure.

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Until we get into a stage where safety aids like ESP is made mandatory, drive your car in the way its suppose to be driven, and probably its good to take the warning sign below seriously (Source: (Renault Duster : Official Review))
In Australia and Europe, since 2011-2012, I believe that the Motor Vehicles Authorities have made ESP as compulsory across all new vehicles being registered, regardless of their type, manufacturer, origin or any other consideration.
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Old 11th July 2013, 15:34   #35
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Default re: Evasive manoeuvres & Rollovers?

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Originally Posted by phamilyman View Post
Thanks to the mods and govigov for refocusing this thread appropriately. Do we have any hard evidence in the Indian scenario?

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Originally Posted by .anshuman View Post
ESP with Roll over Mitigation is one of the most important safety features when it comes to SUVs with high COG and soft suspension, a feature which most manufacturers conveniently choose to ignore for our market. Obviously it cannot compensate completely for bad handling behavior.
This thread started with the OP asking whether there was a calculation involved in deciding whether a vehicle (SUV) will rollover or not.

I am not sure why the focus was changed, possibly because youtube videos of cars doing Elk test are lot more interesting than some basic high school physics. The fact that the Elk test involves a DOUBLE correction which is hardly encountered in India is quietly ignored.

How do you think the ESP works? It has a lateral acceleration sensor.

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Please understand what I mean by destructive testing before asking me to understand lateral acceleration test.

By lateral acceleration test you are talking about testing the rollover resistance of SUV. If the vehicle rolls-over, it is pretty much destroyed, that is my meaning of destructive testing.
For someone who ridicules Indian technical graduates for the lack of basic technical understanding, I am surprised at such a response from you.

How can you conclude that the test is destructive if you don't understand how to do the test?

Like I said before, please look up lateral acceleration testing, or skidpad testing, and then decide whether the test is "Destructive" or not.

Cheers.
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Old 11th July 2013, 16:01   #36
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Default re: Evasive manoeuvres & Rollovers?

Not just SUV or UV, a bad driver can beat all physics! Its a Honda City that has toppled here!

http://www.team-bhp.com/forum/street...ml#post3173456
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Old 11th July 2013, 16:10   #37
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Default re: Evasive manoeuvres & Rollovers?

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For someone who ridicules Indian technical graduates for the lack of basic technical understanding, I am surprised at such a response from you.
You shouldn't be. Technical graduates are trained to be engineers. But the car reviews in India are done by regular people with no real background in automotive testing. As of now there is absolutely no minimum criteria in driving skill for a car reviewer. For example, it is not uncommon to see a reviewer with no AT experience, reviewing an AT car. Therefore reviews are strictly from an regular driver or enthusiast point of view. There is no equipment/gauges to measure anything, or the technical expertise to calculate anything. If there is such expectation, I wouldn't qualify by a mile.

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How can you conclude that the test is destructive if you don't understand how to do the test?

Like I said before, please look up lateral acceleration testing, or skidpad testing, and then decide whether the test is "Destructive" or not.
I read up on lateral testing and even watched some videos before replying to you the very first time. In the hands of some over-enthu reviewers, I can easily imagine the SUV toppling during the fast turns.
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Old 11th July 2013, 16:16   #38
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Originally Posted by shankar.balan View Post

In Australia and Europe, since 2011-2012, I believe that the Motor Vehicles Authorities have made ESP as compulsory across all new vehicles being registered, regardless of their type, manufacturer, origin or any other consideration.
Somewhat OT: it was criminal ( oh well, they could get away with it) of Toyota to offer the classic Fortuner without VSC. That is one key feature I envy in the new Fortuner. Makes a difference in such a tall suv.

Our local laws need to get tougher on the manufacturers. No airbags, no esp/ vsc in the lower variants e.g. in hatches or sedans. The government has chaperoned our inefficient manufacturers and helped increase/ maintain their profitability enough. Danda is required.
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Old 11th July 2013, 16:27   #39
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Default re: Evasive manoeuvres & Rollovers?

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There is no equipment/gauges to measure anything, or the technical expertise to calculate anything. If there is such expectation, I wouldn't qualify by a mile.

I read up on lateral testing and even watched some videos before replying to you the very first time. In the hands of some over-enthu reviewers, I can easily imagine the SUV toppling during the fast turns.
I did not mention Team Bhp reviewers in any post. I mentioned Magazine reviewers, or to make myself clearer, print media. They are in the business of reviewing cars, and if one is paid to drive and review a car, that makes one a "Professional" driver. Now, my point from the beginning, which is OT to the thread, is that Indian magazines are not being professional. If no testing is involved, isn't quoting 0-100 times and other specs just plain plagiarizing unless source mentioned? If they are not hiring professional drivers, diluting the test is not the answer.

Coming back to skidpad testing, how can going round a large circle faster till one cannot stay in the circle be destructive? The fact that someone does the test wrong does not make the test itself destructive. You probably need to look up "Destructive testing" to understand what that means.

Cheers
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Old 11th July 2013, 17:02   #40
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Default re: Evasive manoeuvres & Rollovers?

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Originally Posted by gthang View Post
I did not mention Team Bhp reviewers in any post. I mentioned Magazine reviewers, or to make myself clearer, print media. They are in the business of reviewing cars, and if one is paid to drive and review a car, that makes one a "Professional" driver.
I am trying to tell you that there is no difference except they are professional writers and we are enthusiast freelance writers. Throw in the professional bloggers, and the confusion is complete.

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Originally Posted by gthang View Post
The fact that someone does the test wrong does not make the test itself destructive.

You probably need to look up "Destructive testing" to understand what that means.
I have already clarified what I meant by destructive testing, I obviously was not referring to the classical meaning as in crash testing with dummies. I meant it can be destructive in the hands of amateur test drivers.

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Coming back to skidpad testing, how can going round a large circle faster till one cannot stay in the circle be destructive?
The test drives are always conducted on public roads, in a route marked by the manufacturer. There is no large circle or testing equipment. And it can be destructive because of drivers who redline even in a circle or a curve.

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From the description provided in the opening post, it does appear that this guy was driving like an absolute idiot. The stretch where this appears to have taken place is a narrow road with loads of curves, including innumerable blind corners. I know because I drove on this patch just a week back. Am just glad it was a bus and not an innocent motorcyclist in his path.

Unfortunately, for some folk, testing a car only means to recklessly redline it 100% of the time. I've seen reviewer monkeys whose tests start & end with wheel spins. Forget driveability or mid-range, their sole objective is to gauge what the limit is (theirs or the cars, that's a million buck question).
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Old 11th July 2013, 18:12   #41
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Default re: Evasive manoeuvres & Rollovers?

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I have already clarified what I meant by destructive testing, I obviously was not referring to the classical meaning as in crash testing with dummies. I meant it can be destructive in the hands of amateur test drivers.
Does your definition of the term change the meaning of the term?

Destructive testing: "Prolonged endurance testing under the most severe operating conditions, continued until the component, equipment, or product specimen fails (is broken or destroyed). The purpose of destructive testing is to determine service life and to detect design weaknesses that may not show up under normal working conditions."
Read more: http://www.businessdictionary.com/de...#ixzz2YjvN7K68

If skidpad testing was destructive, how many cars do a typical US magazine go through for their review?

What is stopping the Indian car magazines, or even Team Bhp, from getting a large enough tarmac area, some traffic cones and a tape measure? Mild restraint while testing is not too much to ask for, is it?

Only when you understand the concept of lateral acceleration, will you properly understand vehicle dynamics. You can watch all the youtube videos you want on Elk tests, which seems to be the choicest medium of learning here, without really getting a clue.

Cheers.
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Old 11th July 2013, 18:17   #42
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Regardless of the calculations involved in ascertaining whether and at what speed a vehicle will roll over or not, the only factors that WILL EVER matter is lots of common sense coupled with lots of experience. Dilution in any of these two factors would make all calculations in this area a beautifully pointless exercise.
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Old 11th July 2013, 18:33   #43
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Default re: Evasive manoeuvres & Rollovers?

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Originally Posted by gthang View Post
This thread started with the OP asking whether there was a calculation involved in deciding whether a vehicle (SUV) will rollover or not.

I am not sure why the focus was changed, possibly because youtube videos of cars doing Elk test are lot more interesting than some basic high school physics. The fact that the Elk test involves a DOUBLE correction which is hardly encountered in India is quietly ignored.

How do you think the ESP works? It has a lateral acceleration sensor.
GThang,

It is a natural progression for the thread. The OP simply asked about the angle / speed at which a SUV will topple. But others pointed out that it was not as much the sheer angle (since this is not an OTR scenario) but the sudden change in direction at high speeds that result in a vehicle toppling. That's where the elk test came in.

I personally think discussing specific tests such as the elk test are more valuable (controlled data) than a generic meandering discussion about the maximum tilt a vehicle will take before it topples. Its been designed keeping a use case in mind (which IS quite relevant for India btw) and has hard data - http://www.teknikensvarld.se/algtest-lista/ . What's not to like? of course Good point re the elk test being a dual correction.

Please do share the 'high school basic physics' that would be less interesting but more accurate in its calculation - its an open thread, we can change the course as long as we can answer the basic question with the best information possible.

Last edited by phamilyman : 11th July 2013 at 18:47.
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Old 11th July 2013, 18:42   #44
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Default re: Evasive manoeuvres & Rollovers?

I just used a wrong word, I only meant dangerous testing. I deeply apologize of the wrong usage, I am no automotive professional to have known better. And no, I don't believe I can learn all about lateral testing over youtube, that is why I am not trying hard to research it despite your urging. I only looked up the web for basic understanding before replying.
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Old 11th July 2013, 18:49   #45
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Default re: Evasive manoeuvres & Rollovers?

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Originally Posted by gthang View Post
... I mentioned Magazine reviewers, or to make myself clearer, print media. They are in the business of reviewing cars, and if one is paid to drive and review a car, that makes one a "Professional" driver. Now, my point from the beginning, which is OT to the thread, is that Indian magazines are not being professional. ...
Quote:
Originally Posted by gthang View Post
Does your definition of the term change the meaning of the term?...
Print Media pays its' reviewers for writing, which is their actual profession, not driving. If reviewing involves driving, it is incidental - that doesn't make them 'professional drivers' like racing and stunt drivers. There are very few 'print media' in the world (2-3) whose writers have the ability to drive to conduct tests the proper way. Done the proper way, the testing is done by engineers who have been trained in all aspects of driving including safety, and they are not 'professional drivers' by any flight of imagination.

It is difficult to understand why, after admitting that your point is OT, you are persisting in trying to make your p-o-v understood with the same flawed methodology you are accusing others of.

Last edited by DerAlte : 11th July 2013 at 18:56.
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