Seite - 30 - in Proceedings of the OAGM&ARW Joint Workshop - Vision, Automation and Robotics

the corresponding metadata and tool catalogues. The purpose of the CES is to lower the integration barrier of cloud services for SMEs. Its key functions are the management of CAD data. The CAD-files are of particular interest within RobWood, but also within non-spatial information such as processingsequences,whichshouldbemademoreaccessible and easily available through the cloud-exchange services. Cloud services may also be used to evaluate this data. Fig. 5. Scheme of the Cloud Exchange Service Unit. A general structure of the system is shown in figure 5. The system is developed on the basis of microservices architecture explained in [15], which provides more flexibil- ity, resilience and scalability than a monolithic architecture. These microservices are small services that are in charge of small tasks. So, it is possible to build the whole system by the combination of them. The microservices are independent and connected through a RESTful API [11]. If needed, there can be added more microservices with few changes in the system architecture. C. Cell Controller The cell controllers main purpose is to request new data from the MES, optimize it for the specific robot platform and forward the prepared data to the robot. Besides that, it also serves as a human device interface, visualizing the status of the robotonadetailed level, giving theusermore insight into the tasks performed by the robot. The information received from the MES contains all necessary data to automatically produce the elements on the carrier which is currently at the robots station. This includes all panels to be cut and placed, the steam brake and the drillings and clamping positions. Depending on the layer of the data blocks, their complexity and their position (e.g. path planning) a rearrangement of those can be done by the cell controller to increase cycle time and decrease waste. Each of these data blocks represent a single task to be performed at the robot. Furthermore, the cell controller monitors the stock of raw materials and alerts the user if the cell runs out of timber or gypsum panels. Errors detected during production and the progress of the production unit are reported to the MES as well, depending on their severity and the kind of repair actions to be taken. Finally, after all tasks have been committed by the robot, the cell controller notifies the MES and requests the next production unit. D. Robot The robot is the last instance in the production line of the manufacturing process. It consists of a control unit able to receive new tasks from the cell controller. Each task consists of a single work package, e.g. contour and position of a panel. This package is handled by the robots control unit and split into single mechanical movements. The most important abilities of the robot are cutting, positioning, clamping and stapling the panels as well as placing the steam brake and drilling holes (e.g. for power outlets). After the robot gets the task assigned to place a panel, it has to lift the panels out of the store. While doing so, it has to check if enough panels are on stock for future proceedings. If this is not the case it has to indicate the cell controller to notify the user. Since the refilling of the panel storage is not automated, the user has to fill these by hand. After lifting the panels, the robot places them on a dedicated work bench, the carrier, where the cutting is performed. The cutting is executed according to the contour information handed over by the cell controller. Depending on the material to be cut (e.g. timber, gypsum) the robot will change its tools automatically. Since the work bench is sloped down, the waste and dust emerging during cutting slips off the panel and has not to be removed explicitly. This allows that further layers can be positioned without an additional cleaning step. When all parts of a layer are positioned, the robot gets the instructions to nail the panels. Again, the tools are changed and staples or nails are driven through thepanels into thebeams to tighten them.Depending on the layering of the element the steam brake is applied after this step.To doso, the roll containing the steambrake is released and the robot pulls off the steam brake from the roll. After reaching the desired length, an orthogonal cut is made and the roll is locked again. After applying the steam brake, additional layers of panels can follow where the previous described steps have to be repeated. When all layers of the element are produced, the robot starts to drill holes through the panels and the steam brake before the production unit is released and handed over to the next production station of the plant. E. Quality Inspection Unit The Quality Inspection Unit (QIU) is used for supervising the clamping process required to combine different wooden elements. It consists of a number of components, which are shown in figure 6. Again, the units main parts are marked in gray. Avisual inspectionsensor ismounted inoron thephysical set-up in the production cell or even on the robot arm itself. This sensor data is processed by the Sensor Control and 30