Study on scheduling algorithm for multiple handling requests of single automated guided vehicles

To solve the problem of small amount of machining centers in small and medium flexible manufacture systems(FMS), a scheduling mode of single automated guided vehicle(AGV) is adopted to deal with multiple transport requests in this paper. Firstly, a workshop scheduling mechanism of AGV is analyzed and a mathematical model is established using Genetic Algorithm. According to several sets of transport priority of AGV, processes of FMS are encoded, and fitness function, selection, crossover, and variation methods are designed. The transport priority which has the least impact on scheduling results is determined based on the simulation analysis of Genetic Algorithm, and the makespan, the longest waiting time, and optimal route of the car are calculated. According to the actual processing situation of the workshop, feasibility of this method is verified successfully to provide an effective solution to the scheduling problem of single AGV.

基于非支配排序遗传算法的涡轮发动机转子系统装配参数优化

为探究保障转子系统高温动平衡的最佳装配参数方法,掌握高温下动平衡的变化规律,提出转子系统各零件装配角矩阵的优化确定方法。基于高温工况下热-结构动平衡理论模型和零件材料特性随温度的非线性变化规律,建立转子系统动平衡随温度变化的解析方程;根据不同装配参数下系统不平衡量和偏移扭矩的差异,把高温动平衡优化问题转换为多目标多变量的优化问题,给出基于非支配排序遗传算法的解决方案;以某弹用涡轮发动机高压转子系统装配为例,在600℃工作环境下对所提方法进行验证,得到该工况下零件最佳装配角矩阵,以及最小化温度对转子系统动平衡的变化量影响,改善了装配质量特性。结果表明,零件装配角对高温工况下转子系统动平衡变化有很大的影响,通过装配参数优化可显著减少高温工况对多零件转子系统动平衡的影响。