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In-situ thermoplastic automated fiber placement (TP-AFP) is a lean additive manufacturing process without further vacuum bagging and autoclave cycling. Heated by laser and subsequently compacted with a consolidation roller, the tapes are consolidated on the fly. This makes TP-AFP a single stage manufacturing process. For this highly transient process inline quality assurance (QA) is vital. The inline QA sensor is situated about 100 mm behind the consolidation roller and measures height profiles via laser triangulation. The evaluation routine identifies gaps and overlaps between tows and tracks as well as early/late cut at the beginning and end of each track. Processing the profile data includes outlier removal, thresholding, bitwise operations, the Sobel operator, erode and dilate operations and contour finding. We present the data evaluation of a full-scale fuselage skin of a test shell which was produced with a multitow laying head that processes three ½” carbon fiber tapes. The primary focus is the detection of gaps and overlaps. A 3D spatial plot will give an overview where the production process has to be revised.

Künstliche Intelligenz und Analytics halten immer mehr Einzug in den Wissenschaftsalltag. Gerade der Umgang mit Daten aus komplexen multi-Schritt Experimenten stellt heute noch eine Herausforderung dar. Das am DLR entwickelte integrierte Datenmanagementsystem "shepard" [1] vereinfacht den Einstieg und die Verarbeitung dieser Daten. Im Folgenden wird kurz auf die Motivation hinter Experimentaldatenmanagement eingegangen. Danach wird die Basisarchitektur der Einzelkomponenten von shepard dargestellt. Am Beispiel von thermoplastischem AFP wird die kontextualisierte Datenerfassung verdeutlicht und abschließend ein Ausblick auf Weiterentwicklungsperspektiven gegeben.

Ein Produktentwicklungsprozess im Bereich der Luftfahrt verläuft in der Regel entlang eines fest vorgegebenen Pfades der durch bestimmte Meilensteine gekennzeichnet ist. Nach der Produktidee mit der entsprechenden Marktanalyse muss ein Missionsprofil erstellt werden. Dafür werden vom Overall Aircraft Design (OAD) sogenannte Top Level Aircraft Requirements (TLARs), wie Traglast, Reichweite usw. definiert. Im Anschluss durchläuft man diverse Designphasen (Conceptional, Preliminary und Detailed) mit jeweils steigendem Detailierungsgrad. Sobald die Konzept- und Vorentwurfsphasen durchlaufen sind, ist der Spielraum für Designänderungen gering. Ein Großteil der Produktentstehungskosten fällt jedoch erst in der Produktion an. Designänderungen, die auf besondere Anforderungen der Produktion zurückzuführen sind, sind zu diesem späten Zeitpunkt nur unter extremen zusätzlichen Kostenaufwand zu realisieren. Im DLR-Projekt URBAN Rescue soll unter anderem dieses Problem angegangen werden. Durch eine agile interdisziplinäre Strukturauslegung, die bereits in der frühen Designphase eine Rückkopplung von Statik-, Crash-, Fertigungs-, und Produktionsanforderungen ermöglicht, sollen kostenaufwendige Designänderungen in der Produktion reduziert werden. Hierzu soll eine Methodik entwickelt werden, die den Rahmen für die abteilungsübergreifende Kommunikation stellt und auf den gesamten Entwurfsprozess anwendbar ist. Ein Fokus liegt hierbei auf der Beschreibung der Kommunikationswege ohne diese zu automatisieren. Daher sollen Schnittstellen definiert werden, die in agilen und hochfrequenten Auslegungsloops frühzeitig potentielle Fallstricke verhindern. Anhand der Fertigung einer ausgewählten Demonstratorstruktur soll die Funktionalität der Methodik getestet und bewertet werden. Die vorliegende Arbeit zeigt den aktuellen Stand auf und gibt einen Überblick über die bis 2024 im Projekt geplanten Arbeiten.

At the Center for Lightweight Production Technology (ZLP) a pick and place process using cooperating robots for the draping and handling of large textiles in the production of a rear pressure bulkhead from carbon fibre reinforced plastics (CFRP) has been developed and presented in the past. This work has primarily shown the feasibility of draping and handling large cut-pieces with passively adjustable end-effectors that can reproduce spherical geometries. The process chain developed recently is mirroring a complete industrialized production and incorporates different technologies developed at our facility. Sub-processes include the planning of grip- and drop-points based on the ideal tool geometry, preprocessing of the data, automated adjustment of the grippers, cut piece detection and finally a collision-free path planning system for the robots. The process chain was used for several plies within the production of a full scale demonstrator of a rear pressure bulkhead. This work depicts the current state of the development and shows the results of the full scale application of the process. Opportunities and limitations of the setup for an industrial environment are discussed.

During the last decade the DLR Center of Lightweigth Production Technology (ZLP) in Augsburg investigated the potential of the autonomous production of composite parts by means of pick and place executed by industrial robots. Starting from conventional teaching the research focus was extended to the development of technology bricks for computer vision based gripping, automated derivation of grip- and drop coordinates from CAD data, digital process description and workflow, autonomous cut-piece transfer by means of collision free path planning and a multi-robot synchronization and execution layer. The technology bricks are enriched by a process data acquisition system and controlled by a manufacturing execution system embedded into a high-level process control system. In this work we give an overview of the developed technologies and achievements based upon several use cases from the field of composite production.

Automated Dry Fibre Placement (DFP) is considered a viable technology for preform production of advanced composites. In this process, the heat source crucially determines the achievable lay-down rates and thus ultimately the effective productivity. Therefore high energy density heat sources are desirable. In this context, flashlamp heating is a promising technology especially for large part production. In this study, the Heraeus humm3 flashlamp system is benchmarked to infrared (IR) radiators in terms of peel strength and heat distribution at various lay-down speeds. For this purpose a parameter study is conducted to identify suitable processing parameters for binder activation. A significant increase to lay-down speeds of 30 m/min compared to 6 m/min with infrared heaters is accomplished with enhanced controllability of the process regarding the energy transfer into the material. The temperature profiles measured indicate more uniform distribution along the tracks. Subsequently the opportunities and limitations of applying a flashlamp heat source in a DFP process are discussed.

The recent progress in additive manufacturing technologies has led to new freedom in respect to part design. Strongly undercut and inner geometries can be manufactured as an integral structure. In the course of the development of an automated preforming process for small batch freeform CFRP components at the German Aerospace Center in Augsburg, the possibility of additive manufacturing for preform toolings was assessed. A segmented preform tooling made from polyamide 12 enriched with aluminum powder was manufactured in a selective laser sintering (SLS) process. Apart from the formative geometry additional functions were integrated in the design, such as pneumatic fixation of plies, heating, cooling as well as the integration of sensors for the monitoring of process parameters. The results of the automated preforming process are generally favorable. However, inherent disadvantages of additive manufacturing, like thermal warpage, need to be considered in order to determine the suitability of the tooling for the preforming process. Therefore, an analysis of geometric variance and performance of the integrated functions is done. The results are critically examined against the background of the preforming process and used to discuss opportunities and limitations of additively manufactured toolings for the general application in production of preforms.