A Robust Optimization Method for Location Selection of Parcel Lockers under Uncertain Demands

Parcel lockers have continuously growing in popularity as an alternative mode for last-mile delivery services due to their capability of effectively alleviating the risk a failure, increasing possibility consolidation, and reducing number drop-off sites. However, poorly located parcel be less efficient. When determining locker location, inadequate consideration uncertain demands can potentially increase unsatisfied demands. To remedy this issue, robust optimization model is proposed paper with demand uncertainties, including large small parcels received sent. Not only collection locations optimally determined, but so each location at same time under various levels. Meanwhile, sites whose are covered by one also determined constraints acceptable walking distance. A series numerical experiments has been performed evaluate model, main focus being on solution robustness. Since set non-linear transformed into linear counterparts, obtained existing solvers within reasonable moderate computing power. The experimental results provide useful guidance practical application method, slightly more conservative decision making secure robustness marginal costs.