- The application scale of Embedded systems Automobile industry is umongous as of our ever revolutionising modern world.
- They have imposed total control on automobiles.
- Almost all components within a regular car is under control of Embedded System.
- The ECU (Electronic Control Units is being extensively used in automobiles.
- The Electronic control units comprises of microcontroller as well as digital signal processors.
CARS WITH EMBEDDED AIRBAGS:
- Mercedes, BMW cars and other modern vehicles make use of a variety of controllers such as ECU’s used in Embedded Systems.
- The Airbag is a one of a kind(popular) protection device that employs crucial safety for the passenger against a deadly head crash.
- Mainly it was designed for for the individuals sitting in the front.
- Microcontroller is the core of the system.
- The system performs operations based on the commands fed by microcontroller.
- The input Power to the controller is supplied by an external battery.
- Next the sensor then detects it and the controller(ECU) activates the Airbag with the aid of alternator.
BLOCK DIAGRAM FOR EMBEDDED AIR BAG SYSTEM
- Actually the main concept of an airbag is to decelerate the passenger’s abrupt forward movement as evenly as possible in a fraction of a second.
- The airbag comprises three major components in order to achieve this goal.
- The main part that is the bag is comprising of a thin nylon fabric, which is folded and placed into the steering wheel or dashboard or, more recently, into the seat or door.
- Sensor is the alerting device that gives the signal to the bag to inflate.
- The Inflation process tends to happen when there is a equivalent collision force of that running into a brick wall at 16 to 24 km per hour.
- Afterwards a small mechanical switch is turned on when the required mass force is detected.
- This humongous force closes one electrical contact, thereby informing the sensors that the car has crashed..
- The sensors will receive information as electrical data input from an accelerometer embedded into the microchip.
- Mainly inside the airbag inflation system NaN3 (sodium azide)chemically reacts with KNO3(Potassium nitrate) to yield nitrogen gas.
- Consequently the very hot bursts of nitrogen gas expands the airbag rapidly.
PRINCIPLE OF SAFETY:-
- The main concept here is to reduce Interior-impact energy by absorbing devices augment restraint systems that absorbing energy from the occupant while minimizing injuries.
- In 1967 the energy-absorbing steering column was discovered, which is quite a good example of such a type of device.
- Other secondary car components such as Instrument panels, windshield glass may be hit on by an unseatbelted occupant, they can also be designed to absorb energy in a appropriate safe manner.
The Future of AirBags:
- Many Activities dedicated in improving the lifesaving benefits of airbags are in progress.
- Now they use much improved “dummy” injury situation based on new research to update their knowledge of car safety.
- The results indicate that 40 percent of all fatal injuries resulted from accidents are the result of side impacts whereas the remaining 30 percent of all accidents are unfortunately side-impact collisions.
- BMW specialist engineers have recommended door-mounted airbags. The door has more space permitting a bigger bag that facilitates much more coverage.
- The ITS (Inflatable tubular structure aka head bag) resembles a big sausage in dimensions .
- As opposed to other airbags, it is designed to stay inflated intact for a duration of about five seconds to offer better protection against possible second or even consecutive third impacts to the driver.
- When using the side airbag, the ITS is supposed to offer better protection in some side collisions.
- An alternative option for head protection in side impacts is the curtain airbag.
Whatever we have discussed above concisely explains that the science of airbags is still quite new and under major reinvention.