The Study Of The Multi-layer Fault Injection Method For Navigation Simulator Based On ARINC Specifications

In the process of developing Chinese own large aircraft C919, the airworthiness is a very important step for whole project. In order to verify the reliability of the navigation system, ensure the function of the navigation system stable and correct, a large number of tests must be carried out in the development periodic. When doing test work, various avionics units need to work together and provide data to other units. The problem is that not every avionics units will complete at the same time. In this condition the simulator will be used to conduct the testing work.The method of fault injection is proposed to test the navigation simulator. With this method, the variety of random failure exist in the system, such as short circuit, open circuit, signal distortion, signal error can be simulated and make them to be tested. Besides the fault model in fault injection is controllable, measurable, which can provide great enough support for testing and development work of the navigation systemFirstly, the structure of the whole navigation simulator, the ARINC429 standard and every unit of the navigation simulators is studied, which can provide standards for fault injection. Then the fault injection technology is studied. The location of fault injection is decided and a multi-level approach, and different method to inject fault in different layer are proposed. Then the types of faults from the physical layer, the electrical layer, protocol layer and application layer are summarized. Based on these, the quintuple fault model is built, and two ways are proposed in order to optimize the series of faults which will be injected. Finally, the injection system in protocol layer and application layer is contributed by software. The purpose and function are analyzed. Besides the process, the implementation and the user interface are designed.