A multi-objective dynamic covering location problem for hierarchical agricultural machinery maintenance facilities

Abstract

It is essential to design a product service system with the adequate location of maintenance facilities for guaranteeing the fast and dependable response to failures of extremely busy agricultural machinery during harvest time. This paper aims to optimize where to locate/relocate two hierarchical levels of facilities respectively composed of maintenance stations and mobile service fleets over multiple periods of a harvest season to support the safe and stable operation of agricultural machinery. We formulate a multi-objective dynamic covering location problem for these hierarchical facilities that seeks to maximize the total demand covered within some response radii while minimizing the modification to facility locations between the periods. The augmented ɛ-constraint method based on lexicographic optimization is then developed to obtain a set of non-inferior solutions that allow us to evaluate the trade-off between multiple decision objectives. Lastly, a real-life problem is handled to illustrate the effectiveness of our multi-objective decision model and solution method. Computational results recommend the optimal decision of facility locations for implementation, examine the sensitivity analysis of selected parameters, and compare the solution obtained from the proposed model with the period-specific solutions that take no account of the changing locations of facilities between the periods.