Open Access

Interoperability at the field level is dependent on the specific technology implementation and its semantics. Integrating field devices with different communication protocols is not a simple process, as there is no direct semantic mapping between them. In recent years, standards such as the OPC UA Field eXchange and the Asset Administration Shell have proposed neutral data models to reduce the heterogeneity of field device semantics. However, to integrate different field device standards, a formal mapping between the semantic terms of these standards and the neutral data models must still be defined. A research topic that remains open is how different standards can be automatically mapped to a neutral interface independent of their implementation. In this paper we present a novel approach that generalizes the semantics of field devices at the communication level, enabling the use of inference rules that are independent of specific standards. Our method, based on the Industry 4.0 Field Device ontology, identifies the generic type of any field device and provides an interoperable capability description adaptable to various protocols. The framework includes a semantic broker that automates the creation of device instances, executes inference requests, and generates a generic semantic model for field devices. The objective of this work is to simplify the integration of field device semantics, with a generalization of the application layer and facilitate their mapping to other higher-level data models.

Industrial field devices exchange information through standardized communication interfaces and data models, encompassing process data, communication properties, and vendor details. Despite enhancing interoperability within a specific protocol, integrating these devices with diverse systems poses challenges due to data model fragmentation and custom interfaces. The absence of a universal semantic model for categorizing field device process data independently of standards necessitates engineers to repetitively devise custom exchange data models for different sensors and actuators, relying on standards like OPC-UA. In response, this work proposes an ontology-based architecture to tackle information data model fragmentation, aiming for seamless data interoperability across a universal interface. By focusing on two open-access field device standards, IO-Link and CANOpen, we compare their information data models, identify existing limitations, and put forth a semantic information model. The objective is to offer an interoperable interface for Industry 4.0 applications, showcasing the potential of an ontology-based approach in streamlining data exchange and reducing heterogeneity among field devices.

Establishing high-performance polymers in additive manufacturing opens up new industrial applications. Polyetheretherketone (PEEK) was initially used in aerospace but is now widely applied in automotive, electronics, and medical industries. This study focuses on developing applications using PEEK and Fused Filament Fabrication for cost-efficient vulcanization injection mold production. A proof of concept confirms PEEK’s suitability for AM mold making, withstanding vulcanization conditions. Printing PEEK above its glass transition temperature of 145 °C is preferable due to its narrow process window. A new process strategy at room temperature is discussed, with micrographs showing improved inter-layer bonding at 410°C nozzle temperature and 0.1 mm layer thickness. Minimizing the layer thickness from 0.15 mm to 0.1 mm improves tensile strength by 16%.

The thermal conductivity of components manufactured using Laser Powder Bed Fusion (LPBF), also called Selective Laser Melting (SLM), plays an important role in their processing. Not only does a reduced thermal conductivity cause residual stresses during the process, but it also makes subsequent processes such as the welding of LPBF components more difficult. This article uses 316L stainless steel samples to investigate whether and to what extent the thermal conductivity of specimens can be influenced by different LPBF parameters. To this end, samples are set up using different parameters, orientations, and powder conditions and measured by a heat flow meter using stationary analysis. The heat flow meter set-up used in this study achieves good reproducibility and high measurement accuracy, so that comparative measurements between the various LPBF influencing factors to be tested are possible. In summary, the series of measurements show that the residual porosity of the components has the greatest influence on conductivity. The degradation of the powder due to increased recycling also appears to be detectable. The build-up direction shows no detectable effect in the measurement series.