The influence of weights in the TOPSIS and TMAL methods on the order-picking time – simulation analysis

Abstract

In shared storage, the product is often located in many different (often very distant) locations. When completing an order, one of them (or several if visiting one will not cover the demand for the product) should be selected. Locations can be selected according to different criteria: distance from the I/O point, from other locations to be visited during the picking process, degree of demand satisfaction or according to product storage time. One or all of the criteria listed above may be used. For this purpose, multi-criteria decision-making methods can be used. One of the methods used to select a location is TMAL (Taxonomic Measure of Location's Attractiveness) based on Hellwig's Composite Measure of Development, and the other is the well-known TOPSIS method. The aim of the article is comparison of results obtained by both of these methods. Both methods have been compared in terms of the total distance the picker will have to travel during order-picking and the total picking time. Obtained results showed that the shortest order-picking route and time was obtained when the highest weight was put on the degree of demand satisfaction. Also, generally the TOPSIS method generated better results than the TMAL method although only for the order-picking time results were statistically significant.