The beverage industry is predestined for automated transportation and material flow - especially as the storage processes in this sector often involve large quantities of uniform and easily stackable goods. Block storage systems with a high degree of space utilization and a high degree of flexibility at comparatively low costs are common here. The latter can be further reduced by automated processes, saving the operator time and, not least, reducing potential sources of error. In addition, suitable technologies also help to make many processes more ergonomic.

In order for an AGV to achieve the desired results, a number of key questions must first be clarified as part of the system design:

• What load is to be transported and transferred and how?
• How maneuverable does the vehicle need to be and how much space is available?
• How long are the routes?
• How many transports will be carried out per hour?
• Which lane guidance or navigation is best suited?
• What does the energy concept look like depending on the duration of use?
• Are there any special safety aspects or difficult environmental conditions?
• Is a simple call control system with traffic control sufficient or is a complex control system with a wide range of functions such as a warehouse management system required?

An example: The specific task of a company from the beverage industry was to develop an AGV for a block storage system that can hold 10,000 pallets on a storage area of 80 × 80 meters. The pallets were to be stacked automatically and precisely on top of each other on four levels. The top pallet had to be able to be set down or picked up again at a height of approx. 5.2 meters. A major advantage of the block storage system is its high level of flexibility: as it does not have any shelving at all, it can be converted without any major technical effort - i.e. storage rows can be moved and rotated, for example.

With its double fork with fork adjustment, the fully automated counterbalance truck enables two pallets to be transported at the same time - with scanners at the front and rear to ensure personal safety.

© EK Automation

As a solution to this task, EK Automation, a company specializing in transport robotics solutions for automated material flow and storage systems based in Rosengarten, Lower Saxony, proposed fully automated counterbalance trucks with a lift of 5.5 meters and equipped with a double fork with fork adjustment for transporting two pallets simultaneously. Specifically, these were vehicles from the so-called Compact line, whose models are optimized for the medium-heavy load range of up to 2,500 kilograms load weight. The Compact GG used is characterized by a compact design and a chassis with a small turning radius, making it ideal for use in block warehouses with narrow aisles. It achieves lifting heights of up to eight meters and a travel speed of up to 2 m/s forwards and backwards.

Various types of navigation can be combined with the Compact GG. In the case described, for example, hybrid navigation was used, which is controlled via laser scanners and magnetic points. Laser navigation is used to determine the position, i.e. a laser sensor attached to the AGV determines the current vehicle position with the help of reflectors mounted at various points in the hall. Magnetic point navigation, on the other hand, is responsible for the route taken by the magnets embedded in the floor along the lane. A PC server is responsible for guidance control and all communication is handled via WLAN.

Last but not least, an important aspect of an AGV system is the suitable energy system. Factors such as duration of use, shift operation, investment costs and flooring all play a role here. In the example chosen, the decision was ultimately made in favor of an efficient automatic battery system with automatic recharging, which guarantees an optimum supply around the clock.

Pallet recognition in 3D

A special feature of the case described is the height that this block storage system reaches with a transfer height of 5.2 meters. This was only made possible by a new development from EK Automation: its vehicles can be equipped with 3D pallet recognition for precise stacking at great heights. This allows precise evaluation of the actual position of the pallet and therefore reproducible storage and retrieval as follows: The forklift moves to the programmed target position, creates a 3D photo and evaluates it. The fork position is then adjusted laterally and in the lifting height according to the pallet position and the vehicle picks up the pallet safely.

Special safety measures are also required if a warehouse is to be automated in which people also move around. For this purpose, EK Automation has developed a modular system that can be used to put together a combination of safety devices optimized for the specific application. In the case of the block storage system, the vehicles are equipped with personal protection scanners at the front and rear to protect employees. With these scanners, which allow the warning and protective fields to be set flexibly, the vehicle is able to scan its surroundings precisely - even when driving with the forks in front. If a person or object enters the protective field, the AGV brakes gently. However, in the case described above, where goods are stacked four levels high, only trained service personnel may be present in the warehouse.

In principle, automated warehouses in the beverage industry can be designed in different ways using AGVs: From individual buffer rows for dispensing or picking up pallets provided in production or in the warehouse to area-filling buffer rows. A classic example is production running over three shifts and goods issue running over two shifts. The automated guided vehicle system then takes over the buffering of ongoing production in a block warehouse during the night shift, for example, and at the same time provides the goods for dispatch in the outgoing goods area.

Author:
Ronald Kretschmer is Head of Sales & Marketing at EK Automation.