The Study Of The Test Methodology For Engine Control Software Base On The Hardware In The Loop

With the social demand to the automobile engine control system becomes increasingly high and the engine control system becomes more and more complex.Timely testing on the controller software and finding bugs in the software development process could significantly lower the cost of development and shorten the development period.Firstly,this thesis designed the hardware and software integrated engine ECU test platform based on hardware-in-the-loop simulation technology,which includes the building of hardware environment and the development of software environment.The hardware environment includes the selection of emulator board and engine controller and the design of peripheral circuit.The software environment includes the design of the engine ontology mode.The design of man-machine interfaces and the development of automatic test software enable the platform to have the condition of automatic test of the engine control software.Secondly,the engine control software was analyzed in detail,including the underlying driver,application support software and the application layer.Through the analysis of the engine control software and based on the strategy of test item extraction,the test items and test points of the engine control software were extracted.And the test cases were rationally distributed according to the distribution strategy of the test cases.The equivalence class division method,boundary value method and scene method were used in black box testing,meanwhile,the test cases were designed for each test point and the test scripts were developed.Finally,the automated test script file was executed and the test report was analyzed and classified in detail.The failed test cases were distributed in matrix,which makes the test items and test points with high error rate clearly and as a result re-distributed the test cases,then complemented the regression test.At last,the test cases were all passed.The hardware and software integrated test platform of the engine ECU developed provides the technical means for the integration of the hardware and software of the engine controller;the proposed software testing strategy optimizes the distribution of test cases and improves the test efficiency;the automated test script library developed can be reused in software testings,which lays the foundation for improving test efficiency.