Research On The Functional Test System Of Airbag ECU In Vehicles

As the automobile industry develops,people are having higher demands of active safety system and passive safety.The passive safety system is activated when an accident is unavoidable so as to reduce the damage to the driver and passengers in the vehicle.As a core component in the passive safety system,the performance of the airbag is gaining attention.There are two major performance indicators for the airbag.One is functional,which includes the function of self-diagnosis and the function of crash output,the other indicator is robustness,which includes anti-aging and anti-interference capabilities,etc.The test system designed by this research project is to test whether the functional indicator of the airbag controller meets customer demands.Currently,the test methods adopted in China are mainly done either manually or semi-automatically,or the controller is put in the vehicle to test.Testers need to record all the data manually during the test,therefore,various abnormal conditions happened during the test can not be recorded reliably.It is difficult to find the root cause when something goes wrong with the controller during the test.Although putting the controller inside the vehicle is a relatively reliable way to test,but the cost of a single test is enormous.After analyzing the shortcomings of the manual test and the whole vehicle test method,this paper introduces an automatic test system of the airbag controller.During the testing process,there are precision monitoring devices and the whole process is controllable,which makes it evidence-based.Crash output is the main function of the airbag controller.After the crash happens,the airbag controller will send out a series of signals to set off the airbags,and broadcasts the crash information to the whole vehicle network.The design of this research project emulates the whole vehicle environment needed by the airbag controller through establishing a simulation system and the surrounding environment,then it builds a database to store the crash signals,and designs a precise signal import process through a special signal generator.So that the crash signals can be transferred to the altered airbag controller within control,and finally,the test result can be judged from its behaviors,thus realizing the test of the crash output in an emulated whole vehicle environment.Self-diagnosis is another important function of the airbag controller.It diagnoses all the nodes of the passive safety system and shows the diagnosis result through different codes,which is actually the feedback to the parameter changes of surrounding environment.This project designs a dynamic configurator between the airbag controller and the surrounding environment.It changes the environmental parameters of the controller by means of changing the state of relay in the dynamic configurator.It then observes and records the behaviors of the airbag controller through the devices connected to it.And automatically assesses the test result using testing script,hence realizing automated testing.Through practical examples,this paper shows that the test system of the airbag controller function designed in this research is more efficient and more reliable than traditional test methods with greatly reduces the test cost.At the end of this paper,it summarizes what need to be improved in this research and looks into the future of the intelligent test systems.