2017/01: Alvey introduces a new slotting and mapping tool


Alban Plait-DoinIn the distribution world, optimisation is key. Getting products in and out with a minimum of errors and a minimum of handling, transport, walking – in short, with a minimum of people, is key.

Warehouses are optimised, in the vast majority of the cases, when these are installed. However, this optimisation may “evaporate” for a number of reasons. First, there often is a strong seasonal variation. Secondly, businesses evolve. New products come in, others slowly fade out. Customers need change. Volumes, generally, are growing.

In order to help our customers manage this challenge, Alvey introduces its “slotting and mapping” tool. This tool allows the customer to analyse and optimise its warehouse continuously. 

Slotting and mapping are based on the expected book of orders to be implemented in a certain time interval.


Slotting first works on mutually independent references. The number of calls, and thus the daily dispatched volume, is determined according to the reference volumes in litres and frequency of their occurrence in the order book. If we adapt those data to the location types available to the customer (most often a logistical warehouse), the references can be classified in a table with two inputs, one for the number of calls, the second for the dispatched volume.

For example, a volume reference A called once will represent the same dispatched volume as reference B, which is 10 times smaller but called 10 times. The tool will select the same type of a picking carrier, but another strategy of location to optimise the movement of personnel.

To optimise the stock replenishment, we determine the location type (plate, static, dynamic or a pallet) where we store each reference. Slotting, thus, aims for optimising both the picking activity and the stock replenishment (global optimisation is performed).


Warehouse automation by AlveyOnce slotting is performed, mapping can start. Neither mapping is based on individually taken references, but on the occurrence frequency of the same units of two or more references in individual orders.  Based on these units of references and the division of individual types of carriers in the “stations” of picking, it aims for grouping the “friendly” references into one station. This will make it possible to minimise the number of stops in the station of cartons or crates for the order preparation.

Mapping considers the following limitations:

  • Zone limitation (obligatory or prohibited presence of certain references in certain stations) 
  • Limitation of the type together/not together (obligatory or prohibited simultaneous presence of certain pairs of references in the same station) 
  • The level of personnel involvement: maximum number of command lines which can be processed by one operator in one station. If this number is achieved, no other references are assigned to this station.

Mapping performs meta-heuristics to obtain an optimised solution based on the initial solution.;

The quality of such solution is evaluated by two criteria: 

  • Total number of stops in the station necessary to implement the complete order book.
  • Number of task of warehouse re-organisation (see below)

Connector to WMS

After mapping is finished, the stage of warehouse re-organisation starts. In order to do so, the tool is connected to the customer´s WMS to know the common division of references in the stations. Based on that, it will create tasks the purpose of which is to change the warehouse to the state recommended by mapping.

There are 3 kinds of tasks:

  • New references: the warehouse does not know the reference.
  • Stock replenishment: the reference is known but it is not stored anywhere.
  • Warehouse optimisation: the warehouse knows the reference but it is stored in another type of location or in another station than recommended by mapping. In this case, it will be necessary to relocate it directly or to exchange its location with another reference, which is in the target warehouse, and the third station can be passed through.

To plan the reorganisation tasks, the tool offers the tasks to the manager.

The manager maintains the control over the tool and he/she can select the tasks to be implemented. Such tasks will be transmitted to WMS, which will execute them as any other tasks of the transmission of stored goods. It is completely transparent for replenishment operators like picking operators.

The management of picking location requires the sources designed to maintain a good total output of the logistical centre. Good location rules will enable to gain 15 % to 20 % from the total output. Our tools just facilitate for the manager the work with long analyses causing frequent problems. 

Alban Plait-Doin
Group IT Director

For more information, do not hesitate to contact our industrial software sales team