复杂箱体零件柔性机加工生产线平衡优化

Optimization of Flexible Machining Line Balancing for Complex Prismatic Parts

摘要:

解决复杂箱体类零件柔性机加工生产线平衡问题,需在操作平衡分配的同时考虑各工位操作的执行顺序对最终优化目标的影响。在分析该问题相关约束及优化目标的基础上,提出了在生产线平衡优化的同时得到各工位最优或接近最优操作排序的方法。在引入工艺及工位约束的基础上,综合考虑加工中心的换刀及转位功能,以生产线节拍最短和成本最低为目标建立优化模型。采用粒子群算法求解,提出了一种启发式的译码方法,使每个粒子都能映射到一个满足约束的生产线平衡方案,引入了Pareto档案集,实现了多目标优化并结合精英保留策略提高了算法效率。最后,通过实例验证了该方法的有效性。

关键词:箱体零件;生产线平衡 操作排序;粒子群算法 启发式译码

Abstract:

To solve the machining line balancing problem for complicated prismatic parts, the execution sequence of operations should be considered during the line balancing process. After analyzing the constraints and optimization objectives, a method has been presented, which can provide optimal or near-optimal assignment of operations to the stations and sequence of operations inside the stations simultaneously. Based on the constraints of process and workstations, taking the tool change and rotation capabilities of machine center into consideration, this problem was modeled aiming at minimizing cycle time and cost of the line. Particle swarm algorithm was use to solve this problem. A heuristic decoder was designed for the algorithm to permutate each particle to a feasible line balancing plan. Pareto set was introduced to realize the multi-objective optimization and the algorithm efficiency was improved with elitist preserving strategy. Finally, a case was illustrated to prove the validity of the proposed method.

Key words:prismatic parts, line balancing, operation sequencing, particle swarm algorithm, heuristic decoder