Development Assurance Level Assignment Based on Multiobjective Optimization by Using MOPSO in Aircraft and System Development

Development assurance level (DAL) is the metric used to denote the rigor level of development assurance tasks performed on functions or items. The fundamental principles of DAL assignments are provided in SAE ARP 4754B. The present DAL assignments are only performed by the principles, whereas the probability requirements of top-level failure conditions are not considered in the process. In addition, cost and weight are both important factors that should be considered in aircraft and system development. In this study, an approach to DAL assignments based on multiobjective optimization is proposed. Taking the DAL assignment principles and probability requirements as constraints, the model can make a tradeoff between development cost and weight. Multiobjective particle swarm optimization is utilized to solve the model. The method is applied to a fly-by-wire system. Compared with typical multiobjective evolutionary algorithms, the DAL assignment schemes obtained by our method have better performance on both convergence and distribution.