Three new smart team players

04.07.2017

The Früh Verpackungstechnik AG [Früh Packaging Company] in Fehraltorf, Switzerland, has been using three automated guided vehicles (AGV’s) by Stöcklin Logistik AG since the end of 2016. The basic version of the EAGLE ANT limits the scope of features to what is actually required, without irrelevant frills. This reduction to basics promises a quick return on investment and is also extremely easy to put into service.

Under the motto “Safety for your products” the Früh Packaging Company, packs exactly what is most important and valuable for customers: their products. This family company can look back on nearly four decades of continuous tradition, during the course of which continuously innovative packaging solutions were developed for their demanding customers. The range includes primarily blister and see-through packaging as well as stand-up, sealed edge, side fold and peel pouches. Früh Packaging occupies a leading position, particularly in the areas of “Flexible Packaging” and “Medical Co-packaging”. Work is accomplished under clean room conditions. All processing and packaging operations are validated to ensure they fulfill the highest standards for hygiene and security. Continuous traceability is also guaranteed. Moreover the products are regularly tested for climatic resistance, strength and durability.

Deluxe Trolleys

Maximum quality, transparency and security are also ensured in the area of intralogistics, the focal point of the supply chain implemented for supply and proper disposal at the production level. Since the end of 2016, these processes have been supported by the three, independently-operating, automated guided vehicles, which automatically move between the various floors as well as the three buildings. These intelligent helpers, developed on the basis of a low platform elevating truck and called the EAGLE ANT 0, are designed for a payload of up to 1,500 kilograms to provide raw materials, semi-finished products, finished goods and boxes to the various target stations on Euro pallets. In the course of this work they travel distances of up to 300 meters per trip. These routes are, however, not reserved solely for the AGV’s; they are also crossed by pedestrians and forklifts.

“With the EAGLE ANT we have conceived a product for a special market niche”,

declared Bernd Krebs, who is responsible for production of the AGV's at Stöcklin Logistik AG in Aesch, Switzerland. “The idea was to develop a automated guided vehicle, combining a manageable number of central, basic features with a comparatively economical price, which can also be upgraded easily.” The vehicles in use at Früh Packaging do not communicate with one another. A traffic management system (TMS) installed on a master computer books and places orders, manages the vehicles, interchanges data and controls the elevators. The TMS also regulates and coordinates traffic between the vehicles.  

A WiFi system also ensures proper communication. Individual as well as multiple orders can be initiated in parallel. A so-called scheduler is integrated into the TMS to manage the travel orders in the correct sequence and priority and transfer this information to the vehicles via the TMS. A so-called Web interface (e.g. Google Chrome or Firefox) provides user access to the TMS, thus allowing observation as well as modification of the individual travel orders. All vehicle alarms (e.g. error messages), statuses, travel, etc. are also indicated by the TMS.

Focus on Safety

As soon as a pallet is placed at a specified position by the personnel, the TMS receives a corresponding signal and assigns a travel order to the next free AGV in the vicinity. Each order station is preliminarily assigned a defined number of inbound and target locations to which the pallet can be transported with its load. The load carrier is detected by three sensors. Two optical sensors are located in the fork tips to prevent a collision, when an obstacle is in the vehicle’s way. An inductive sensor is attached to the switching vane, which is activated by the pallet. Inductive sensors in the elevating mechanism serve for visualization of the status, e.g. “Pallet raised” or “Pallet lowered”. Motion in the fork direction is accomplished very slowly (max. 0.3 m/s) for safety reasons and indicated by an acoustic signal for personnel in the immediate vicinity.  

In addition, a safety laser scanner with detection angle of 270 degrees is installed on all vehicles in the direction of forward motion. This scanner serves for navigation and as a safety feature for personnel and obstacles. If anything is detected in the monitoring field of the laser scanner, the AGV stops automatically. The trip can be resumed only after the monitoring field has been cleared completely. This can be accomplished automatically or manually with a button. In both cases, acoustic and visual signals inform all personnel in the surrounding area. The warning and safety fields adapt dynamically depending on the direction of motion and speed. In each case the warning field is larger than the protective field and it is adjusted so that when a field is infringed, the vehicle is braked to a stop, before the protective field is reached or infringed. This prevents emergency braking maneuvers, which could lead to (additional) subsequent damage, such as the cargo tipping over.

Integrated Elevator Control

The vehicles orient themselves primarily on walls and stationary ambient contours, suitable for navigation. If required in certain situations, reflectors can also be attached near the floor. The AGV’s move between floors using elevators, which are also controlled by the TMS, which coordinates the travel orders and vehicles. When an AGV has reached a position in front of an elevator, it sends a request signal for an elevator to the TMS. After the AGV has moved into the elevator cage and reached its stop position, the elevator receives a signal from the TMS to move to the target floor. When this destination has been reached and the AGV has moved out of the elevator, the elevator is again free for use by personnel. However automatic AGV operation always has priority. Therefore when a new vehicle again approaches the elevator, wide ranging signal lights (outside and inside the elevator cage) announce “Robot operation”, requesting the personnel to exit the elevator immediately. The cage itself is also monitored. If humans or objects are still present in the cage, the AGV cannot enter.

Highly Efficient and Scalable

The EAGLE ANT “crew” is supplied with energy by Stöcklin’s own lithium ion batteries as well as CAN bus communication to the AGV control and the chargers. 

“The particular feature of the Stöcklin Power Package is clever battery management and an active cell-balancing system unique worldwide, to ensure maximum availably and long service life“,

explained FTS expert Bernd Krebs. The batteries are also absolutely maintenance-free; overheating is not possible. Intermediate charging is possible at any time and a full charge requires a maximum of two hours. When active orders are not present for individual vehicles, they are automatically sent to the charging station. 

During the start-up phase for the automated guided vehicles (AGV's) a teach-in trip is completed to scan and save a map of the operating area. This map then includes the walls, stationary ambient contours and reflectors as well as all routes, along which the automatic vehicles move. This map also includes waiting points, where it is necessary for the vehicle to wait for another vehicle, before moving into a certain area. Then there are decision positions, at which the AGV communicates with the master computer. This is, for example, always the case when it is necessary to assign a free pallet storage space or request an elevator to change floors.  

Since start-up in November 2016, the automated guided vehicles from Stöcklin have proven their suitability as high performance, compliant team players in everyday use. Transport routes are used together with personnel underway on foot or with forklifts. Collisions as well as superfluous waiting times are a thing of the past. If reinforcement is required in the future, additional vehicles can be integrated into the team at any time, easily with plug & play. Any changes in routes are just as easy to implement as function upgrades. Ultimately even incorporation into a Warehouse Management System (WMS) is possible.