Development Of Airbag Electronic Control Unit

This paper introduces vehicle passive safety system firstly. Many foreign government and auto-makers have paid high attention to vehicle safety system long years ago, and made its regulation or even law to regulate the new vehicle R&D, and gives customer a guide to distinguish safe car and unsafe car. Vehicle safety system can be divided into 2 parts, one is active safety system and the other is passive safety system. Active safety system works before car crash, to something to prevent the crash or accident, while passive safety system works once after a car crash or accident, to eliminate or reduce the injury to the passengers in the car. Passive safety system comprises deformable and energy-absorbable car crash zone, reinforced passenger cabin and pillar, seatbelt system and airbag system. Airbag ECU (Electronic Control Unit) is the core part of the passive safety system. It make the decision and command the seatbelt and airbag to deploy or not. The airbag ECU detect the vehicle movement and if a car crash or accident being detected, the ECU will do algorithm to see if the crash is severe enough to deploy the airbag or seatbelt. If yes, the ECU will set ignition current to fire the airbag and seatbelt. The ECU is capable to do diagnostics of the whole safety system. When any error being detected, the ECU will store the error code and illuminate the airbag warning LED to inform the driver about the fault. This article gives the analysis of the airbag ECU development. Relative test data and form have be included also to provide better understanding of the development. You can also find the diagnostics function and fault code management in this article. Firing strategy and algorithm is key to discriminate a crash. The last part of this dissertation provides personal point of view and assumption of what the safety electronics system could be or should be, what new feature should be developed into the airbag ECU in the future.