Importance measure-based phased mission reliability and UAV number optimization for swarm

Nowadays, the missions of the unmanned aerial vehicle (UAV) swarm are very common. However, it is still difficult to calculate the phased mission reliability of UAV swarms. Meanwhile, there is no method to measure the effect of changes in the number of UAVs on reliability. Furthermore, how to determine the number of UAVs in swarm to maximize mission reliability is also a challenging issue. Hence, the reliability of a single UAV is analyzed based on phased binary decision diagram. Then the calculation method of mission reliability is given by modeling the swarm mission as a k-out-of-n system with phased requirements. What's more, some importance measures are proposed to describe the effect of changes in the number of UAVs on mission reliability. In addition, an optimization model is established to maximize mission reliability by reasonably arranging the number of different UAVs in the swarm. The importance measure and marginal optimization algorithm are combined to solve the optimization model. Finally, the change law of mission reliability is analyzed and the advantages of the proposed solving method are demonstrated.