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Airbag

technology Maturity 7-9

An airbag is a soft bag.

Peugeot 306 airbags deployed.jpg
Peugeot 306 airbags deployed.jpg
It stays inside the car. It puffs up fast during a crash. The bag helps keep you safe. It is like a soft pillow.
Vauxhall Vectra curtain airbag deployed.jpg
Vauxhall Vectra curtain airbag deployed.jpg
Do you like soft pillows?

44 words

An airbag is a soft bag in a car.

Peugeot 306 airbags deployed.jpg
Peugeot 306 airbags deployed.jpg
It stays hidden inside the car. It puffs up very fast during a crash. This happens in just a tiny bit of time.

Sensors feel the crash. They tell the car to blow up the bag. The bag is a soft cushion.

Vauxhall Vectra curtain airbag deployed.jpg
Vauxhall Vectra curtain airbag deployed.jpg
It helps stop you from hitting hard parts of the car.

It can work with your seat belt. The bag is a helper for the belt. This helps keep everyone safe on the road.

94 words

An airbag is a safety tool in a car.

Peugeot 306 airbags deployed.jpg
Peugeot 306 airbags deployed.jpg
It is a soft, fabric bag. It stays hidden until a crash happens. Its job is to give people a soft cushion. This helps stop them from hitting hard parts of the car.

How does it work? First, crash sensors feel the hit. These sensors send news to a computer unit called an ECU. The ECU uses a special math rule called an algorithm. This rule decides if the bag needs to pop out. If it does, the bag inflates in just a few milliseconds. This happens very fast! Most bags use a small chemical reaction to fill up. Some newer side airbags use compressed air instead.

Airbags are called "passive" restraints. This means they work without you doing anything. This is different from seat belts. Seat belts are "active" because you must buckle them. Today, airbags work with seat belts to help keep you safe.

Vauxhall Vectra curtain airbag deployed.jpg
Vauxhall Vectra curtain airbag deployed.jpg
Modern cars can have up to ten different airbag modules.
Curtainairbags.JPG
Curtainairbags.JPG
These can be for the driver, the passenger, or even the sides of the car.

190 words

An airbag is a special safety tool inside a vehicle.

Peugeot 306 airbags deployed.jpg
Peugeot 306 airbags deployed.jpg
It is a soft, fabric bag designed to inflate very quickly. Its main job is to provide a cushion for people inside. This cushion helps prevent injuries during a collision. It creates a soft surface between a person and hard parts like the steering wheel. It also protects people from hitting the dashboard or the windshield.
Curtainairbags.JPG
Curtainairbags.JPG
Modern cars can have up to ten different airbag modules. These can be for the driver, the passenger, or even the sides of the car.

How does the airbag work during a crash? First, crash sensors feel the impact of the collision. These sensors send important data to a computer unit called an ECU. This unit uses a crash algorithm to decide if the bag should deploy. The algorithm looks at the type and the angle of the hit. If the crash meets certain rules, the ECU triggers a firing circuit. Most airbags use a pyrotechnic process to inflate. This means a small chemical reaction happens to fill the bag. This whole thing happens in just a few milliseconds.

2008-04-14 Airbag control unit.jpg
2008-04-14 Airbag control unit.jpg

The history of the airbag is very long. In 1919, two dentists named Arthur Parrott and Harold Round filed a patent. Their idea was for covering parts of vehicles and airplanes. Later, an American named John W. Hetrick filed a patent in 1952. He was an industrial engineer in the United States Navy. He wanted to protect his family on the road. He used his experience with navy torpedoes to help design it.

Original Airbag Design Blueprint 1953.png
Original Airbag Design Blueprint 1953.png
He did not get much money for his invention, even though it was very valuable.

Many people helped make the airbag what it is today. In 1967, Allen K. Breed invented a sensor using a ball in a tube. This sensor could inflate an airbag in under 30 milliseconds. In the 1970s, General Motors began offering airbags in some cars. They called their system the Air Cushion Restraint System, or ACRS. These early cars included a 1974-style Oldsmobile instrument panel.

Interior of 1975 Buick Electra.jpg
Interior of 1975 Buick Electra.jpg
By the late 1980s and early 1990s, many more cars began using them. In 1988, Chrysler became the first US maker to make driver airbags standard.

It is helpful to know how airbags fit with other safety tools. Airbags are called "passive" restraints. This means they work without you doing anything at all. This is different from seat belts, which are "active" restraints. You must actively buckle a seat belt to use it. Because of this, airbags are meant to be a supplement to seat belts. They work together to keep people safe during a crash.

Lives Saved by Safety Belts and Air Bags, NHTSA, DOT.svg
Lives Saved by Safety Belts and Air Bags, NHTSA, DOT.svg
This teamwork helps minimize the effects of a collision.

472 words

An airbag, also known as a supplemental inflatable restraint, is a critical vehicle safety system.

Peugeot 306 airbags deployed.jpg
Peugeot 306 airbags deployed.jpg
It consists of a flexible fabric cushion, an inflation module, and an impact sensor. The primary goal of the system is to provide soft cushioning for occupants during a collision. By doing this, the airbag creates an energy-absorbing surface. This surface sits between the person and hard interior parts like the steering wheel, instrument panel, or windshield. It helps reduce injuries caused by the occupant flailing against the vehicle's interior during a crash.

The mechanism of deployment relies on a complex chain of electronic and chemical events. First, crash sensors in the vehicle detect an impact. These sensors send data regarding the collision type, angle, and severity to the airbag electronic controller unit (ECU). The ECU then runs a crash algorithm to determine if the impact meets specific deployment criteria. If the criteria are met, the ECU triggers firing circuits. Most traditional modules use a pyrotechnic process, which is a chemical reaction, to inflate the bag in milliseconds. Newer side-impact modules may instead use compressed-air cylinders to achieve inflation.

Modern vehicles utilize a wide variety of airbag configurations to protect different parts of the body. A single car may contain up to ten different airbag modules. These include driver and passenger frontal airbags, as well as side-curtain airbags. Other types include seat-mounted, door-mounted, and pillar-mounted modules for side impacts. There are also specialized designs like knee bolsters, inflatable seat belts, and even pedestrian airbag modules.

Curtainairbags.JPG
Curtainairbags.JPG
Each type is placed strategically to address specific collision directions and occupant positions.

The history of the airbag spans over a century of engineering. The earliest origins trace back to a 1919 patent by two dentists, Arthur Parrott and Harold Round. In 1952, American industrial engineer John W. Hetrick filed a patent for an automobile airbag. Hetrick used his experience with United States Navy torpedoes to develop his design.

Original Airbag Design Blueprint 1953.png
Original Airbag Design Blueprint 1953.png
Although his invention was valuable, he struggled to find investment. Later, in 1964, Japanese engineer Yasuzaburou Kobori developed an airbag system that used explosives for inflation. A major breakthrough occurred in 1967 when Allen K. Breed invented a ball-in-tube sensor. This electromechanical sensor could trigger deployment in under 30 milliseconds using sodium azide.

Commercial adoption of airbags evolved through several distinct phases. In the early 1970s, General Motors offered the Air Cushion Restraint System (ACRS) in certain fleet vehicles. These early systems included a driver-side airbag and a passenger-side cushion that protected both the torso and knees.

Interior of 1975 Buick Electra.jpg
Interior of 1975 Buick Electra.jpg
However, GM discontinued the option in 1977 due to low consumer interest. By the late 1980s and early 1990s, the industry saw much broader adoption. Chrysler became the first U.S. automaker to make driver-side airbags standard in 1988. By 1991, U.S. legislation required airbags in most new passenger vehicles sold after 1997.

It is important to distinguish between different types of vehicle safety. Airbags are classified as "passive" restraints because they require no action from the occupant to work. In contrast, seat belts are "active" restraints because a person must manually buckle them.

Lives Saved by Safety Belts and Air Bags, NHTSA, DOT.svg
Lives Saved by Safety Belts and Air Bags, NHTSA, DOT.svg
This does not mean airbags are an alternative to seat belts. Instead, they are designed as supplemental systems to work alongside them. This distinction is different from "active safety" and "passive safety" in general engineering. Active safety refers to systems like anti-lock brakes that prevent crashes, while passive safety refers to systems that minimize injury once a crash occurs.

Today, the airbag is a standard component of global automotive safety. The transition from seeing airbags as seat-belt replacements to seeing them as supplemental systems has improved occupant protection. For example, Mercedes-Benz introduced an integrated system in 1981 that tensioned seat belts and deployed airbags simultaneously.

2008-04-14 Airbag control unit.jpg
2008-04-14 Airbag control unit.jpg
This integrated approach ensures that both the belt and the bag work together to manage the energy of a collision. As technology continues to advance, these systems remain a fundamental part of vehicle design.

677 words
🖼️ Images & Media (18)
File:Peugeot 306 airbags deployed.jpg
Peugeot 306 airbags deployed.jpg
File:Round & Parrott blue plaque unveiling - Andy Mabbett - 2019-03-18 - 05.jpg
Round & Parrott blue plaque unveiling...
File:Original Airbag Design Blueprint 1953.png
Original Airbag Design Blueprint 1953.png
File:Interior of 1975 Buick Electra.jpg
Interior of 1975 Buick Electra.jpg
File:Vauxhall Vectra curtain airbag deployed.jpg
Vauxhall Vectra curtain airbag deployed.jpg
File:Airbag Warning Sticker.jpg
Airbag Warning Sticker.jpg
File:Seitenairbag Porsche.jpg
Seitenairbag Porsche.jpg
File:Curtainairbags.JPG
Curtainairbags.JPG
File:V08232P024.jpg
V08232P024.jpg
File:Gurtairbag.jpg
Gurtairbag.jpg
File:V08589P076.jpg
V08589P076.jpg
File:2008-04-14 Airbag control unit.jpg
2008-04-14 Airbag control unit.jpg

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