Two-stage simplified swarm optimization for the redundancy allocation problem in a multi-state bridge system

• Propose two-stage SSO (SSOTS) to deal with RAP in multi-state bridge system.
• Dynamic upper bound enhances the efficiency of searching near-optimal solution.
• Vector-update stages reduces the problem dimensions.
• Statistical results indicate SSOTS is robust both in solution quality and runtime.

The redundancy allocation problem involves configuring an optimal system structure with high reliability and low cost, either by alternating the elements with more reliable elements and/or by forming them redundantly. The multi-state bridge system is a special redundancy allocation problem and is commonly used in various engineering systems for load balancing and control. Traditional methods for redundancy allocation problem cannot solve multi-state bridge systems efficiently because it is impossible to transfer and reduce a multi-state bridge system to series and parallel combinations. Hence, a swarm-based approach called two-stage simplified swarm optimization is proposed in this work to effectively and efficiently solve the redundancy allocation problem in a multi-state bridge system. For validating the proposed method, two experiments are implemented. The computational results indicate the advantages of the proposed method in terms of solution quality and computational efficiency.