Many software functions currently available in the engine control units have been developed for several years (decades in some cases), reengineered or adapted due to new requirements, what may add to their inherent complexity an unnecessary complication.
This paper deals with the study and implementation of a software reengineering strategy for the embedded domain, which is in transfer from research department to product development, here applied to improve maintainability of flex fuel functions.
The strategy uses the SCODE “Essential Analysis”, an approach for the embedded system domain. The method allows to reduce the system complexity to the unavoidable inherent problem complexity, by decomposing the system into smaller sub problems based on its essential physics.
A case study was carried out to redesign a function of fuel adaptation. The analysis was performed with the support of a tool, which covers all the phases of the method.
When compared with the base implementation, the results obtained from the analysis presents considerable simplification of the control flow and increase of function extensibility. The evaluated software functions can be then reengineered towards not only maintainability improvement, but also other potential benefits from the restructuring, such as reduction of calibration efforts and availability of test cases generation