Safety-critical systems are widely used in many sectors to prevent fatal accidents and prevent loss of life, damage of property, or deterioration of the environment. Implementation of software safety standards as part of the development of safety-critical software is generally considered an essential element of any safety program. Therefore, it has become more critical to produce highly reliable software to meet the safety requirements established by functional safety standards, such as IEC 61508, ISO 26262, and EN 50128. IEC 61508 supports well-known safety mechanisms such as design diversity like N-version (multi-version) programming. N-version (multi-version) programming is a method where multiple functionally equivalent programs are independently developed from the same software specifications. N-version (multi-version) programming is particularly an effective approach to increase the quality of software in a safety-critical system. In this paper, one of the well-known and widely used algorithms in the field of N-version (multi-version) programming, the majority voting algorithm, has been modified with an online stability checker where the decisions of the voter are judged against the stability of the underlying system. The plant where all the theoretical results are implemented is a tilt-rotor system with the proposed N-version (multi-version) programming–based controller. The experimental results show that the modified majority voter-based N-version (multi-version) programming controller provides more reliable control of the plant.

ÖZETBu çalışmada üçüncü seviye yazılım emniyet bütünlük seviyesine sahip bir yazılım için IEC 61508-3 standardında şiddetle tavsiye edilen yöntemler ele alınmış, çalışmada IEC 61508-3 standardı üzerinde yoğunlaşmış ve SIL3 seviyesindeki bir emniyet yazılımı için isterler konusu üzerinde durulmuştur. Geliştirme ortamı olarak IAR derleyici kullanılmış, ayrıca PC-Lint ve MISRA C++ oluşturulan C++ kodunun verimliliğini kontrol etmede kullanılmıştır. Tekil model entegrasyonu için kod örnekleri verilmiştir. Verilen bu örneklerin, emniyetli yazılım geliştirmeye katkılar sağlaması beklenmektedir.Anahtar Kelimeler: yazılım emniyet bütünlük seviyesi, MISRA, IAR, PC-Int, IEC 61508-3, modüler yaklaşım, statik kod analizi SAFE SOFTWARE DEVELOPMENT WITH IEC 61508-3 ABSTRACTIn this study, the highly recommended requirements given in the IEC 61508-3 standard for software with a third level safety integrity level were presented. Especially, the standard, IEC 61508-3, was focused on better developments. SIL3 safety level software's requests have been reviewed. IAR compiler, PC-Lint and MISRA C++ were used for controlling C++ code efficiency. Sample code snippets are given for integration of Singleton Model. Finally, it is expected that the code samples given in this article might provide to safe software and software developments better.