关键词: 装配线, 路径规划, 区间不确定, 鲁棒优化, 改进遗传算法

Abstract: In order to solve the problems that the materials could not be delivered in time due to the uncertain travel time in assembly line material distributions, a vehicle routing planning method with interval uncertain travel time was proposed. The uncertain travel time was represented by interval data. By the robust optimization, the vehicle routing model for assembly lines was formulated based on a route-dependent uncertain parameter. In the model, the objective was to minimize the total travel distance of vehicles with three dimensional loading and time window constraints. A hybrid genetic algorithm was proposed to solve the model. In the algorithm, tournament selection was used to avoid the conversion of fitness values, and a discrete Levy flight was proposed to improve the algorithm search performance. The effectiveness of the proposed algorithm was verified after the comparisons of different algorithms. Finally, the routing planning problem of a gearbox assembly line material distributions was used as an example. The solutions with different degrees of uncertainty were obtained by the proposed method. And the abilities of different solutions to resist the uncertain travel time were analyzed by Monte Carlo method. 

Key words: assembly line, routing planning, interval uncertainty, robust optimization, improved genetic algorithm