Concept of an AirbagScreech …..Bang! Crash! Two cars smashed. Sheet metal cries out in anguish, as if to say why'd you do that? Glass shatters in your face, like a million bee stings! If you ever wreck your car going 30 mph into another car or another object like a tree, you'll be thankful that the airbag deployed. History shows controversy rages with the usage of airbags. Research has shown the positive effects that they have on saving lives. An airbag is a safety device assembled in a motor vehicle. It consists of a bag designed to inflate quickly with air, when a vehicle crashes. The airbag keeps your head from hitting the dash or steering wheel and protects the passengers from being flung into the interior structure of the vehicle. Some people have been saved by them. Other people have never seen airbags deployed in their car. Either way, the airbag has been a national controversy for decades. It is a protective device, but in some cases it has been harmful, and even deadly. Joe Tuha body shop Manager at Sunset Ford has worked in the body shop for 25 years, said "I have witnessed where airbags have saved many lives". Keith Combs (writer for The Body Shop Business, Manager for Bill Roberts Chevrolet) says, "Fact is airbags do save lives, I'm reminded of it regularly.The conception of the airbag, came from a German engineer named Walter Linderer who worked first on a design for an airbag in 1951, that later was patented on November 12, 1953. His design was based on compressed air. However, three months earlier, John Hetrick, got a patent on his airbag issued on August 18, 1953. Hetrick beat Linerer to the punch, even though he started a year later on his design for an airbag (1952), Hetrick got his patent earlier, ironically, making him the founder of the automotive airbag instead of Linderer. Hetrick was an American industrial engineer, retired from the U.S. Navy; he based his design on compressed air from torpedoes. The story behind Hetrick is, he and his family had been driving around the Pennsylvania countryside when a large rock in the road caused Hetrick to veer into a ditch. With no restraint systems, Hetrick and his wife were forced to hold their daughter back, stopping her from hitting the dashboard and saving her life" (as quoted from James Scoltock, from Automotive Engineer), before the dash jumped up and pounded their child. That was the catalyst for Hetrick to develop a system to protect drivers and passengers. Hetrick worked with major car manufacturers, but they chose not to invest. Almost ten years later, around 1963 in Japan, a gentleman named Yasuzaburou Kobori, invented an airbag.[ Which technology modern airbags are constructed, he was awarded patents in 14 countries.] In 1967, Allen K Breed had a breakthrough in airbag sensors. He invented a mechanically- based, ball- in-tube component for front end collisions. It's an electromechanical sensor with a steel ball attached to a tube with a magnet that could inflate an airbag under a 30 milli-second timeframe. Mr. Breed later on came up with another important advancement in the field. Specifically the airbag that vents air as it inflates, minimizing the possibility of second hand injuries by reducing the inflated bags rigidity.Here is Picture of Hetrick's airbag (courtesy of James Scoltock of automotive engineer.)original airbagAirbags first appeared in passenger vehicles during the 1970's. The airbags were mostly encased in the steering wheel center. Like hide and seek, it stays hidden from all eyes. Like playing the game, ghost in the graveyard, the bags wait for that one moment, when they can jump out at you. The bag is made of a thin nylon fabric which is folded up into a compartment of the vehicle. Then in 1998, the federal government mandated that all new vehicles come with dual airbags, one for the driver, and one for the passenger. In the 1970's, General Motors' first airbag was known as the AIR CUSHION RESTRAINT SYSTEM (ACRS). In the mid-1970's, the term for airbags was a Supplement Restraint System (SRS). The airbag at the time they were introduced, the cost was estimated at 3,000 dollars per car. You would have thought that was a bazillion dollars back then. Gas prices were also soaring, that caused more Americans to buy cheaper cars with no airbags. The manufacturers didn't want to deal with the added cost of the airbag. They didn't want to get caught holding the bag.Courtesy of EHS safety news in America 1970,s airbagThe purposes of the airbags are to slow a person's forward movement down, as it moves toward the steering wheel or dash pad. Some people experience that in a crash; time slows down or stops for a moment. As in the case of Samatha Lotti, a certified Biodynamic Craniosacral Therapist in Chicago, She says, "In that moment everything slowed down as if time were the rubber band of a slingshot being prepared to launch. I saw the world outside my car moving fast while everything on the inside was quiet, even still. I experienced the next half a second as if it was 30 seconds, am I approaching the wall, or is the wall approaching me"? The airbag provides a cushion between the passenger, the steering wheel and the dash pad. The airbag's a catcher's glove that catches you in case of a collision. The airbag is designed to deploy within milliseconds and slow the passengers speed to zero, with little or no damage. It's also meant to coincide with a seatbelt, tag team, like Abbott and Costello. Objects in a car have mass, speed and direction. If the object, a person, is not secured in the car, they will continue moving forward in the same direction, with the same speed the car is going. When the car abruptly stops, that force acts on them. Momentum is the product of a passenger's mass and velocity. To stop a passenger's momentum they have to be acted on by a force. The momentum moves measurable mass, making merciless messes. The airbag provides a force overtime called impulse.Airbag deployed (courtesy of car direct.com)Pictures of momentum courtesy of Washington University, departmentThere are three main parts of the airbag system they are the bag itself, the sensors, and the in inflation system. The inflation system is like to a solid rocket booster, the airbag system ignites a solid propellant, which burns extremely rapidly to create a large volume of gas to inflate the bag. The most important parts of the airbag system are the crash sensors. They are extended fingers for the system. They talk to the airbag control unit (ACU). These small electronic sensors are designed to tell when the vehicle has been in an accident. They respond to many different typed of stimuli, such a sudden stop, an increase pressure, as parts of the car are shifted due to a collision. Other sensors measure wheel speed, seat occupancy status, break pressure and impact, while other vehicle status indicators are monitored by the airbag control unit, located in the passenger cabin. These sensors relay signals to the airbag control unit, which in turn can apply seat belt lock, automatic door lock and deploy airbags. A crash trips the sensors that send a signal to the igniter. The heat causes sodium azide to decompose into sodium metal and nitrogen gas, which inflates the bags. Some vehicles have the option to turn off passenger side airbags. Some newer cars have seat weight sensors to distinguish an adult from a child. If the sensor determines it's a child, the inflation pressure is reduced. 1 23The inflation system uses a solid propellant and an igniter.Diagrams of an airbag in a steering wheel (see figure 1, 2, 3) the airbag and inflation system is stored in the steering wheelAre there dangers to these airbags? The airbag requires high speed deployment of up to 200 miles per hour. The process is like a punch from Mohammad Ali, whap, the process takes about .04 of a second. Is it jumping at the speed of light? In some cases the airbag deploys even if the vehicle has not been in an accident. Actions such as slamming the door too hard bam, or riding over potholes, bump, can cause the accidental deployment (whoosh). Airbags use chemical reactions to inflate; the residue can cause skin irritations or minor burns. The airbag itself can cause injury, as well as scraps and lacerations. The airbag works best if accompanied with a seatbelt. The passengers should maintain 10 inches away from the airbag. Airbags can be especially dangerous to children because they are designed for average size adults. Children are generally smaller. They do not fare well with bag deployment. Children under 13 should always ride in the rear seat. This is especially true for children in rear facing seats. Some of the risks that elderly drivers face are the same risks that children have. Some elderly need seat adjustment so that should require the steering wheel to be adjusted to aim the airbag towards the chest instead of the head area. The limitations of airbags are that most vehicles today are only installed with front airbags, although side airbags are offered in newer models. Front airbags don't help in roll over, side impact, or rear end collisions. However, not all airbags deploy as they should. Sometimes, corroded wires or overly touchy sensors can cause the bags to explode randomly, like when you are simply driving along the road. The shock and surprise of this event can cause you to lose control of your car and suffer from a true accident. Additionally, sometimes the airbag may fail to deploy at all, leaving you vulnerable to devastating face and upper body injuries. Airbags are not a substitute for a seat belt.Console and Hollawell ,New Jersey accident lawyers, state on their website that these are the top 5 inventions that make driving safer; windshield wipers, power steering, seat belts, air bags and all-wheel drive. To date, the National Highway Traffic Safety Administration (NHSTA) estimates that airbags saved more than 28,000 lives in the United States. NHTSA also confirms that 290 people have been killed by airbags from 1990 through 2012. The NHSTA also states on their website that the combination of an airbag and a seatbelt is 75 percent effective in avoiding head injuries, and 66 percent effective in preventing serious chest injuries. Until lately, most improvements in safety were in the front and rear impact. Studies show that 40 percent of all serious injuries from accidents are from side impacts. 30 percent of all accidents are from side impacts. Many carmakers are now beefing up the doors by adding heavier intrusion beams. In the b-post (the area behind the door) they are adding extra reinforcement steel and roof sections as well. So if you're driving near or far, and you end up crashing your car, when the airbags out and you're unscarred, you'll be thanking your lucky stars. A Writer on piston heads wrote, " I was a passenger in a BMW 130i, my front and side airbags all went off. Loud, smokey and in shock I walked away from an 80 mph impact with only a cut on my arm. I wouldn't want to try that same accident in a car without airbags or modern crash structure.In the future the automakers may make a program that designs side airbags to deploy in a front collision. Looking more in the future, automakers will begin to fit forward looking sensors to help avoid collisions. We might see airbags deploy just before the crash, with less energy than they do now. All of this makes it pretty clear that the science of airbags is still new and under rapid development. You can expect many advances in this field as designers come up with new ideas and learn from real-world crash data. Joe Tuha (body shop manager of Sunset Ford) says "my experience working in the body shop, I have seen a lot of vehicles that have been involved in accidents". Without airbags the occupants would not have been able to walk away unscathed without the deployment of the airbags. They have proved to me that they play a major role in peoples' safety when involved in an accident".
Courtesy of Washington University Department of chemistry (1,2,and 5a)
Figure 1
This bar graph shows that there is a significantly higher reduction in moderate to serious head injuries for people using airbags and seat belts together than for people using only seat belts.
Figure 2
Deaths among drivers using both airbags and seat belts are 26% lower than among drivers using seat belts alone.
Crash test dummies from getty imagesCourtesy of Insurance Institute for Highway safetySmart Fortwo frontal crash test
