Research on test requirement modeling for software-intensive avionics and the tool implementation

System-testing is an effective way to improve the quality and reliability of avionic software. Using formalized languages to establish the requirement model is facilitated to increase the automatization degree of system-testing. The quality characteristics of software are demonstrated by system behaviors. UML state chart has formal features, and overcomes drawbacks of the traditional finite state machines, retains the advantages of the finite-state modeling, including the marking of nesting and subsequent states; therefore, state-chart is very suitable for detailed behaviors modeling of realtime software. In this paper, based on object-oriented thinking and using state-chart as the core technology, a modeling method is proposed that is suited to establish the requirement model for software-intensive avionics. The method makes abstraction for avionic system common characters, including data, receiving, sending, scenes, events, conditions and period. Using the requirement model generated from the method, and combining with a certain test case generation strategy, test cases and the surrounding environment simulation models of system under test (SUT) can be automatically generated. As an example, the model for the control function of a missile of an aircraft avionics is established by using the method and the model has succinct, intuitive and user-friendly features. And it is also able to support test data generation for different types of testing. Finally, a brief introduction for the implementation of the test requirement modeling (TRM) tool is made. Index Terms: system testing; avionics; dynamic behaviors; requirement modeling; state chart.