24. June 2019
The first step was to select a robot type that satisfied all requirements. For this purpose, an accessibility analysis was carried out with the YASKAWA offline simulation program MotoSim to test the different robot types for viability. The available robots were evaluated with the aid of the layout, to determine which one was best suited to the task. The main focus of attention was placed on the criteria of range, payload, precision and cycle time.
Two robots employed
The final decision was made in favour of the MOTOMAN MH24. With a payload of up to 24 kg, at first sight the latter would appear to be oversized, but here the key factors were the range and design of the robot. The hollow wrist of this model facilitates optimum mounting of tools and easy feed-through of the gripper cable.
In order to reach all participants and guarantee a constant product flow, two robots had to be employed in the pilot installation. One robot was to operate in the wet zone (rinser, filler, outgoing goods) and a second robot was responsible for handling in the dry zone (flame treater, printer, incoming goods). At the interface between the two areas is the XTS table that is to be served by both robots.
Safety concept and system communication
To ensure connectivity to the safety concept, the robots were equipped with YASKAWA’s functional safety unit. This enables, among other things, the definition of safe areas and the integration of tool contours. Equipped with two-channel safety signals, the safety control complies with current safety standards. There were thus no further obstacles to connection of the robots to the overall safety concept.
In order to communicate with the MAS (multi-agent system) an OPC UA server (OPC UA = open platform communications unified architecture) also had to be set up. This technology permits direct communication with each participant, and reading and writing of machine data. This enables the agents (robots, bottles, printer, XTS, etc.) to ‘negotiate’ with each other to determine the best path through the bottling system.
Precision bottle conveyor
The robots’ main task is to safely convey the bottles from each module to any desired station. A double gripper was installed to provide even more system flexibility. The latter enables each robot to convey two bottles simultaneously. Conveyance between the participants should be as efficient as possible, and the bottles must be handled with great precision (printer, flame treater, XTS table) to guarantee smooth running and by-pass all interfering contours. For this purpose whole sequences were programmed to connect logically linked processes (e.g. incoming goods > flame treater > XTS). Additionally, in order to maintain flexibility all individual actions were programmed so that they can be triggered in any desired sequence.
There were many programming and hardware challenges to be met. However, the final result shows that the effort has paid off. A highly flexible and innovative bottling plant has been created, demonstrating that automated bottling with small batch sizes can be cost-effective.
Author: Andrei Craciunescu, YASKAWA Europe GmbH, Allershausen (Germany)
Published in: BRAUWELT, No. 20 (2019), pages 564–565
Contact for readers’ inquiries at YASKAWA: