Research projects

Project CEMAPRE internal

TitleVariants of the Family Traveling Salesman Problem
ParticipantsRaquel Bernardino (Principal Investigator)
SummaryWarehouse activities involve receiving, storing, order picking and shipping goods, with order
picking, i.e., retrieval of items in the warehouse to fulfil customer orders, being the most costly
warehouse activity. One of the operational decisions is the routing, which has been receiving a lot
of attention from the scientific community. However, when analyzing the proposed research method, it
is possible to see that only 28% of the existing literature propose mathematical programming
formulations or metaheuristics. Additionally, it can also be seen that there is a lack of study of
different formulations for the problem and the study of advanced exact methods, such as
The increase in sales of e-commerce led companies to tailor their warehouses to directly serve the
final customer demands in the business-to-consumer (B2C) segment. A common layout of warehouses
dedicated to the B2C segment is mixed-shelve storage, which is a synonym of chaotic storage or
scattered storage, where products with the same stock keeping unit (SKU) do not need to be stored
together. A problem motivated by chaotic storage is the Family Traveling Salesman Problem (FTSP).
Given a depot and a set of subsets of products with several SKUs, the objective of the FTSP is to
determine the minimum cost route that begins and ends at the depot and collects a predefined number
of products of each SKU.
The FTSP was already addressed in the literature, however, there are variants of the FTSP with
practical application that have never been address and may contribute to the literature on warehouse