# A Method for Modeling and Testing Near-Real-Time System Scenarios
## 7 Conclusions  
The scope of system tests performed as part of the unmanned aerial platform certification process requires adaptation to the platform class. This applies to both military and civilian platforms. However, the general approach to managing system scenario requirements and in-flight safety analysis requirements remains the same for all platform classes. In the case of requirements for the certification process, it is worth remembering that they are an extension of the set of system requirements. These requirements focus on checking the correctness of the platform design process, as well as verifying whether the designed system is safe to use.  
This paper briefly discusses the current legal status in the field of testing and certification of unmanned aerial vehicles. The principles of mapping requirements to functions related to flight safety are discussed in detail. This is the first step in the flight system certification process.  
A method of formally describing the system's operation using a UML state machine is also discussed, which was detailed by modeling the system's operation using UML sequence diagrams. A method of transforming models describing processing sequences into EFSM machine models is presented. The method of generating test cases covering all processing paths for a selected system operation scenario is also shown.  
Further research directions will primarily concern increasing the automation of the transformation process of the described models, which will simplify the system testingprocesses. In particular, methods of transforming models in the form of directed cyclic graphs to directed acyclic graphs will be checked.  
Another direction for further work is to verify the possibility of checking models based on techniques based on LTL (linear temporal logic) and CTL (computational tree logic) logic. There are commercially available software tools for formal verification of finite-state systems, such as NuSMV. The tool lets one check finite-state systems for specifications in CTL temporal logic. For example, the NuSMV input language is designed to enable the description of finite-state machines ranging from synchronous to asynchronous. The use of LTL and CTL techniques increases the accuracy of system model verification.  
Conceptualization, T.G. and W.S.; methodology, T.G. and W.S.; validation, T.G. and W.S.; formal analysis, W.S.; investigation, W.S.; writing--original draft preparation, T.G. and W.S.; writing--review and editing, T.G. and W.S.; visualization, W.S.; funding acquisition, T.G.; All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
The original contributions presented in the study are included in the article, further inquiries can be directed to the corresponding authors  
The authors declare no conflicts of interest.  
The following abbreviations are used in this manuscript:  
\begin{tabular}{l l} ATC & Air traffic control \\ CEFSM & Communicating extended finite-state machine \\ DAG & Directed acyclic graph \\ DFS & Depth first search \\ EFIS & Electronic flight instrument system \\ EFSM & Extended finite-state machine \\ FHA & Functional Hazard Analysis \\ FSM & Finite-state machine \\ GCS & Ground control station \\ GDT & Ground data terminal \\ MBD & Model-based development \\ MBSE & Model-based system engineering \\ MBT & Model-based testing \\ MPC & Minimum path coverage \\ OCL & Object Constraint Language \\ UAV & Unmanned aerial vehicle \\ UML & Unified modeling language \\ VSM & Vehicle-specific module \\ \end{tabular}