Hybrid MILP/Simulation/Heuristic Algorithms to Complex Hoist Scheduling Problems

BASÁN, NATALIA P.; CARLOS A. MENDEZ

Proceedings of the 26th European Symposium on Computer Aided Process Engineering ? ESCAPE 26

Elsevier

Año: 2016; p. 1929 - 1934

This paper presents efficient hybrid algorithms based on Mixed-Integer LinearProgramming (MILP), heuristic strategies and an advanced simulation model forcomplex hoist scheduling problems raised in the aerospace and electroplating industries.The aim of this work is to find alternative solution approaches of production andtransportation operations in a multi-product multi-stage production system that can beused to solve industrial-scale problems with a reasonable computational effort. TheMILP model developed must take into account; heterogeneous recipes, time windows,single/multiple unit per stage, zero-wait storage policies, possible recycle flows,sequence-dependent transferring times and load transfer movements in a singleautomated material-handling device. Heuristic-based strategies are proposed toiteratively find and improve the solutions generated over time. In addition, an userfriendlygraphical interface was developed with SIMIO software for quickly evaluatingand validating schedules. These approaches were tested by using real-world data takenfrom the surface-treatment process of metal components in an aircraft manufacturingindustry. Alternative solutions generated by the proposed approach are able to exploitthe inherent process flexibility in order to minimize the operating cost and maximize theproductivity with very low computational effort.