A Model-Based Testing Approach for Cockpit Display Systems of Avionics

Avionics are highly critical systems that require extensive testing governed by international safety standards. Cockpit Display Systems (CDS) are an essential component of modern aircraft cockpits and display information from the user application (UA) using various widgets. A significant step in the testing of avionics is to evaluate whether these CDS are displaying the correct information. A common industrial practice is to manually test the information on these CDS by taking the aircraft into different scenarios during the simulation. Such testing is required very frequently and at various changes in the avionics. Given the large number of scenarios to test, manual testing of such behavior is a laborious activity. In this paper, we propose a model-based strategy for automated testing of the information displayed on CDS. Our testing approach focuses on evaluating that the information from the user applications is being displayed correctly on the CDS. For this purpose, we develop a profile for capturing the details of different widgets of the display screens using models. The profile is based on the ARINC 661 standard for Cockpit Display Systems. The expected behavior of the CDS visible on the screens of the aircraft is captured using constraints written in Object Constraint Language. We apply our approach on an industrial case study of a Primary Flight Display (PFD) developed for an aircraft. Our results showed that the proposed approach is able to automatically identify faults in the simulation of PFD. Based on the results, it is concluded that the proposed approach is useful in finding display faults on avionics CDS.