Abstract This paper studies the problem of creating an optimal flight schedule for a heterogeneous fleet of helicopters tasked with transporting personnel to, from, and between offshore installations. The problem can be modelled as a rich vehicle routing problem and combines the following properties from the vehicle routing literature: pickup and delivery structure, heterogeneous fleet operating out of multiple depots, multi-trip, and temporal synchronization of transportation tasks. We present compact and extended mathematical models of the problem, where the extended model is based on generating all trips apriori. When solving the extended model we apply delayed constraint generation (DCG) to parts of the model to speed up the solution process. Computational results are presented that show that the extended formulation and solution method can solve realistic instances of the problem within one hour. The results further show that the DCG method works significantly better than using lazy constraints from a commercial solver, especially when the number of transportation tasks requiring temporal synchronization becomes large.

中文翻译：

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海上油气物流中直升机飞行调度问题的精确求解方法

摘要 本文研究了为负责在海上设施之间运送人员的异构直升机机队创建最佳飞行时间表的问题。该问题可以建模为一个丰富的车辆路径问题，并结合了车辆路径文献中的以下特性：取货和交付结构、在多个仓库外运行的异构车队、多行程和运输任务的时间同步。我们提出了这个问题的紧凑和扩展的数学模型，其中扩展模型基于生成所有行程的先验。在求解扩展模型时，我们将延迟约束生成 (DCG) 应用于模型的各个部分以加快求解过程。计算结果表明，扩展公式和求解方法可以在一小时内解决问题的实际实例。结果进一步表明，DCG 方法的效果明显优于使用来自商业求解器的惰性约束，尤其是当需要时间同步的运输任务数量变大时。