Little-known effects of car airbags
Car airbags are passive devices that minimize impact and injury to vehicle occupants when a collision occurs.
According to statistics in the US, the airbag system helps reduce the risk of casualties by up to 30%. When the car encounters a dangerous incident, the airbag system will inflate very quickly to create an air cushion to help reduce injuries to the occupants of the car and will quickly deflate afterwards. In some countries, airbags are considered mandatory equipment in cars alongside seat belts.
The airbag system is installed hidden in some positions in the cabin and the chassis. According to the installation position, this system usually includes 4 types: front airbags, side airbags, knee airbags and seat belt airbags.
Front airbags: This is a common type of airbag, usually found in all types of cars. The front airbags are responsible for protecting the head and chest of the front occupants in a frontal collision and are activated when the angle of impact is about 30 degrees to both sides of the front of the car. The airbags will only be activated when necessary. If the collision level is lower than the limit, the airbags will not inflate.
Side airbags:Side airbags protect the head and chest of the occupants when the vehicle is involved in a side impact. There are three main types: curtain airbags for head protection, side airbags for chest protection, and a combination of both. When the vehicle body is subjected to a strong impact or the temperature inside the vehicle is above 150 degrees Celsius, the side airbags will be activated.
Knee airbags:In the event of a frontal collision, the knee airbag will be activated to protect the knee joints of the vehicle occupants.
Airbag on seat belt:The chest of the person sitting in the car always needs to be protected, the airbag on the seat belt has the task of limiting damage to this part of the body when a collision occurs.
Car airbag structure
The airbag system consists of three main parts: the sensor system, the inflator, and the airbag.
The sensor system includes acceleration sensors, crash sensors, side pressure sensors, brake pressure sensors, seat sensors, and gyroscopes. All of these sensors are connected to the airbag control unit.
In the event of a collision, the system activates a series of sensors to deploy airbags to protect the driver and passengers.
The inflator's role is to create gas to inflate the airbag and detonate it when a collision occurs to ensure the safety of the vehicle occupants.
Airbags are made of durable, elastic fabrics and are folded and neatly arranged in positions according to the vehicle's structure. In the event of a collision, the airbag inflates very quickly to create a cushioning system for the occupants of the vehicle to protect and limit injuries.
Working principle
The airbag system in a car is like a “warranty card” for maximum safety of the user in case of a collision. However, in some cases, this device is not effective because the driver does not understand the operating principle of the airbag system.
Airbags and boosters work in a similar way. At the moment of impact, signals from the sensor system are transmitted to the airbag control unit, which sends high-pressure pumps to fill the bag with air. The three stages of the system take only 0.04 seconds from impact to airbag deployment.
Main airbag control system - ACU controls the operation of the sensor system such as collision sensor, speed, acceleration and brake pressure... to determine the level of collision and forward the signal to the airbag control unit. The control unit analyzes the data and can adjust safety features such as automatic door locking, seat belt locking as well as airbag activation. When the level of collision exceeds the specified value of the central sensor, the fuse in the airbag inflator will be ignited.
The detonator starts to produce a current of 1A to 3A in less than 2 milliseconds to ignite the primer and gas generator, creating a large amount of gas. Thanks to that, the airbag is inflated, becoming a cushion to protect the vehicle occupants.
The large amount of gas compressed in a small volume causes the airbag to inflate at a speed of about 300 km/h. Then, the gas in the bag escapes through small holes, the airbag will deflate quickly. The entire inflation and deflation process occurs in about 100 milliseconds, so the person in the car is often unaware that the airbag has deployed.
