航空货站自动化存取系统作业调度优化

为从作业调度角度提高航空货站自动化存取系统运作效率,在分析双板作业和防冲突避让对指令序列完工时间影响的基础上,以指令序列完工时间最短为优化目标,建立了航空货站自动化存取系统调度优化模型,并设计了一种改进的蚁群算法对模型进行求解.为避免算法在搜索过程中陷入局部最优,在引入权重信息素和随机扰动策略的基础上,提出了具有变异率的状态转移参数,用于在寻优过程中决定蚂蚁的移动方向.仿真结果表明:改进的蚁群算法较基本蚁群算法和遗传算法具有更好的全局搜索能力和求解精度,所提出的调度优化方法获得的指令序列完工时间较先到先服务调度策略有至少37%的改进.

Job scheduling optimization of automatic storage and retrieval system at air freight station

To improve the operation efficiency of automatic storage and retrieval system (AS/RS) at air freight station in term of job scheduling, on the basis of analyzing the effect of double unit load device (ULD) transport combination and anti-collision avoidance to the completion time of command sequences, a scheduling optimization model of AS/RS whose objective was to minimize the completion time of command sequences was established, and an improved ant colony algorithm was given to solve this model. To avoid trapping in local optimum in the search process, weight pheromone and random perturbation strategy were introduced. Besides, a state transfer parameter with a mutation probability was proposed to decide the moving direction of ants in the optimization process. Simulation results indicate that comparing with basic ant colony algorithm and genetic algorithm, the improved algorithm has better global search ability and solution precision. In comparison with the first-come-first-served scheduling strategy, the completion time of command sequences obtained by the scheduling optimization method proposed in this paper is improved by 37% at least.