ADVANCE IN CAR SAFETY

ADVANCE IN CAR SAFETY

INTRODUCTION:

The death toll on the worlds roadways makes driving the number one cause of death and injury for young people aging from 15 to 44 which kills more than one million people a year and injuring another thirty eight million seriously. Cars are getting must safer in recent years because safety is the selling point in new cars--people actually seek out and buy safer cars. With the introduction of airbags, crash testing and other smart equipments in the vehicles, the number of people killed and injured by motor vehicles has decreased in many countries.

FUNDAMENTALS OF MOVING OBJECT:

Before looking at the specifics, let’s review the knowledge of the laws of motion. We know, that moving objects have momentum. Unless an outside force acts on it, the object will continue to move at its present speed and direction. If loose objects (passengers, luggage.etc.) in a car are not restrained, they will continue moving with the speed at which the car is traveling, even if the car is stopped by collision. When a car crashes, the force required to stop an object is very great because the car’s momentum has changed instantly while the passengers has not. [1]

When your body is moving at the speed of 35 mph (56 kph), it has a certain amount of kinetic energy. After the crash, when you come to a complete stop, you will have zero kinetic energy. To minimize the risk of injury, the kinetic energy has to be removed as slowly and evenly as possible. Ideally the car has seat belt pretensioners and force limiters which tighten up the seat belts as soon as the car hits the barrier, but before the airbag deploys. The seatbelt then absorbs some of the kinetic energy as you move forward towards the airbag. Milliseconds later the force limiters kick in making sure the force in the seatbelts doesn’t get too high. Next the air bag deploys and absorbs some more of the forward motion for protecting you from hitting anything hard. [2]


for more info visit.
http://www.enjineer.com/forum