Delft University of Technology
Faculty Mechanical, Maritime and Materials Engineering
Transport Technology

E. Bahlmann Automation in Warehouses
Literature survey, Report 2005.TL.7004, Transport Engineering and Logistics.

In this report the automation of processes especially in a warehouse is discussed. Due to changes in the market, warehouses were forced to change their way of working. To follow the questions of the market, it is necessary to increase the productivity (throughput) of a warehouse. To increase the production in an economical way, automation of processes will be a good option.
This report will give an overview of the topics that are enclosed in the mechanisation and automation of processes in a warehouse. First the mission and tasks / processes of a warehouse will be worked out. A description will be given of the different areas in a warehouse and the different types of equipment that can be used. The used equipment can vary from simple hand driven equipment to fully automated systems. Direct relation can be seen between the amount of personnel in a warehouse and the degree of automation. Automation brings high costs in the starting phase but during time, automated systems become more economic because the price per product that is handled will be lower. Finally when it is chosen to automate a certain process the question will rise: What is needed to design and install such an automated system? For this case one process, the stacking and receiving of pallets, will be worked out into detail. The advantages of an Automatic Stacking and Receiving system (AS/R system) will be shown. Furthermore a detailed description of the sub processes and the necessary sensor and actuator systems in the AS/R system will be worked out.

Warehousing is a very old but also very important activity. Warehousing forms the link between the producer and the retailer. Specialism of a warehouse is to gather the goods from producers, store them for some time and then to send them further in the logistic chain.

Warehousing has changed from typical handwork in the past till highly automated systems which are nowadays in use. Developments in this field are still going on. Reason for the change from handwork to automated systems is the question of the market. With automated systems, a warehouse will be able to cope with this question. Customers are asking for shorter delivery times and more, even different types of goods. For a warehouse it will be necessary to work in an economic way. So storage density per square meter must be high, throughput time low and the inventory must even be low. Automated systems have the possibility to give an answer to these conditions. They have a lot of advantages when they are compared with other types of human driven equipment. This literature study gives an introduction to automation in warehouses. Main question is: What are the facts that need to be taken into account when you want to automate a certain part of a warehouse?

In this study, the basic elements, advantages and fields of automation in a warehouse will be worked out. To design a reliable automated system which is able to answer the questions of the market, a lot of study of the working principles of the system is needed. All facts that are related to the system that has to be designed must be considered. Two examples are: the products that have to be handled and the interaction between other types of handling equipment. Very important part of study is the control system of the automated machine itself. How will the system receive the necessary information from the environment and how and with help of which devices can it react and interact with the environment?

To get a better overview of the own control system of an automated machine a practical example is worked out into more detail. The example is the Automated Storage and Retrieval System, a system that nowadays can be found in the more automated warehouse. This system is able to store loads in and retrieve loads from a certain location. For this system are the processes looked up into detail. The different sub- processes are analysed and if possible sub-processes are grouped. For each sub-process it is looked up what type of sensor and actuator system can possibly be installed to control that group of sub-processes. It is difficult to find a sensor / actuator system that exactly answers the design questions. So practical experience and a good consideration of the pro's and contra's of each sensor / actuator system must help to make the final decision for a certain control system. When all different sub-processes have their own control system it will also be important that the different control systems can work together. All different sub-processes have to complete the total process of the equipment. When all sub-processes work in the right way, exclusively and together, a reliable solution is found for the total process.

Reports on Transport Engineering and Logistics (in Dutch)
Modified: 2006.03.06; , TU Delft / 3mE / TT / LT.