The Research On Generating Test Sequences Based On SysML Activities Diagram

With the increasing integration requirements for modern avionics systems integration, IMA(integrated modular avionics system) has come into being. The test for the IMA system becomes a research topic in the field of software testing. Avionics systems' failure is likely to lead to very disastrous consequences, so the quality and safety of IMA system are very important. A complete plan of testing system must quickly produce test data and find errors as soon as possible to remind developers to modify errors, so as to ensure the high quality and safety of IMA. Because the traditional manual testing is time consuming and has problems of low application rates and low efficiency, automated testing has become a main stream of current testing methods. While the UML has become the industry standard modeling languages and has been widely used, there exist some problems, such as, for embedded real-time systems, lack of consistency, poor model interoperability, inadequate capability of engineering modeling in UML. Modeling the activity diagrams in UML is incomplete and short of security analysis. However SysML can specify, analyze, design, verify, and validate a variety of complex systems. So selecting SysML is a reasonable choice to built model for IMA, which is such a comprehensive and high complexity system.We study integration test sequence generation method of IMA systems software. After getting test sequences, we rank the test sequence in priority level to guide the test execution and must meet the coverage criteria faster. Firstly we introduced several test models. We classify, compare, and analyze the characteristics of each model, and describe the IMA system's insufficiency for current models so we put forward to use SysML the activity diagrams to model the IMA system. We analyze the processes in detail from building model to generating test sequences.UML activity diagrams are semi-formal and their concurrent activities cause the leap number of activities path combination. So we formally define activity diagrams to make them understandable and convert activity diagrams into a directed graph to make process easy. In addition, compressing and spreading concurrent activities can avoid the path combination's number skyrocketing. Next we are faced with some problems about how to select coverage criterion and to optimize test sequences. So we compare and analyze coverage criterion of activity diagrams in the aspect of work flow and choose which one can extract more information and more comprehensive test software systems. Finally, BFC(Best Fast Coverage) algorithm is proposed to test sequence priority assignment and to determine the order of executing test sequences so that the set of test sequences has the fastest speed to reach requirements for transfer coverage.We validate test sequence generation method, and verify the BFC validity on the aircraft navigation systems and landing process activity which belong to IMA software systems. When we use BFC to prioritize the test sequences, the transfer coverage is growing faster.