Hybrid Approach to Conduct Failure Prognostics of Automotive Electronic Control Unit

A model/sensor hybrid approach is implemented to conduct failure prognostics of an automotive electronic control unit (ECU). A 3-D finite element model simulating a complex ECU is built, and its predictability is calibrated and verified by an optical displacement measurement technique called moiré interferometry. The stress states of the ECUs during thermal cyclic loadings are documented by piezoresistive-based stress sensors embedded in the test vehicles. The verified model is then utilized to develop a quantitative relationship between the stress senor data and the stress of the most critical locations in the ECU. The modeling and verification steps that lead to the predictive finite element model are described. The stress history of the critical locations obtained by the hybrid approach is presented.