# Center of mass of a car

This might be little of the track but my question is more on possibility of application of principle of center of mass.

The probability of a vehicle overturning depends more on the level of center of mass of the body above the ground, the higher it is and smaller is the base to support it, the easier it is to tumble it.
In case of vehicles on the road, how much is the possibility that lives can be saved to some extent if the driver or some intelligent system in car can let go the tires to bring the center of the mass of body closer to the ground and preventing it from deviating in the traffic to a great extent.
I can fully understand the momentum of the body but it might be helpful in preventing it from crossing over the divider to the other side of the road.
This question is amateur but seeing these horrific videos of road accident, this thought came to me.

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One problem is that a car may tumble. But there's another problem: if the passengers are sitting too low and the floor is too close to the road, a stone on the street may easily make a hole to the car's floor, perhaps to the motor, and to the driver's a. hole. – Luboš Motl Oct 8 '12 at 9:00
@LubošMotl: ya ..nice answer..specially the last part !! – Rorschach Oct 8 '12 at 9:02
The main problem is that drivers often don't know how to control their cars. With limited experience in extreme situations they often over-correct or loose control of the car driving off the road, hitting things, and overturning. No matter what mechanical gizmo you have with an ignorant and distracted drivers lives are going to be lost. – ja72 Oct 8 '12 at 14:14

some intelligent system in car can let go the tires

## 1) "let go" = let go of traction/adhesion

Initiating a skid is likely to be nearly as dangerous as a tumbling vehicle, the system would have to act very quickly before a vehicle overturns and once a lateral skid is initiated it is hard to recover control.

You question assumes that vehicle overturning events mostly occur because of excess lateral friction between tyres and road during extreme cornering or due to side winds etc. In practice it may be that such events are most often caused by an out-of-control vehicle's wheels colliding with a low-level obstruction such as a kerb, a barrier or part of another vehicle.

## 2) "let go" = partially deflate

Modern low profile tyres don't have much height, deflating them would not lower the height of the centre of mass by very much. The safety of road vehicles depends to a great extent on tyres being inflated to the correct pressures, insufficient pressure might lead to sudden catastrophic complete deflation or tyre loss causing rather than preventing an accident.

See

University of Michigan: EVALUATION OF VEHICLE DYNAMIC CONTROL FOR ROLLOVER PREVENTION, 2003

Rollover Warning/Control for Sports Utility Vehicles - "Anti-rollover control did not perform well with evaluation."

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i really think that skidding is less dangerous than a vehicle flipping and than coming to rest, up side down. And the control systems are real time systems, this accuracy can be expected from them. – Rorschach Oct 8 '12 at 9:51
To regain control in a skid requires control of steering, plus plenty of space in which to manoeuvre. It would probably need to be a fully autonomous system without human control. – RedGrittyBrick Oct 8 '12 at 9:55
There is no need to manually stir it in case we have a auto-breaking-system in place. The same system can work out the other exercise as well. – Rorschach Oct 8 '12 at 12:12
+1 for links..! – Rorschach Oct 8 '12 at 16:23

You are describing active suspension which is an option in some cars. Citroen has been using it in many of its cars for years now.

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no actually my question is to lower the centre of mass...suspensions don't really help on thiss – Rorschach Oct 8 '12 at 17:52