Zusammenfassung: Mit in Verbundwerkstoffen eingebettetem Kohlenstoff-Filamentgarn können mittlere Dehnungen großer Messflächen erfasst werden. Zur Abschätzung der messtechnischen Praxistauglichkeit wurden in einen Glasfaser-Polypropylen-Verbundwerkstoff integrierte Kohlenstoff-Filamentgarn-Dehnungssensoren hinsichtlich der erreichbaren Messgenauigkeit bei Kurzzeitmessungen (maximal 15 Minuten Messzeit) untersucht. Anhand vergleichender Dehnungsmessungen mit Metallfolien-Dehnungsmessstreifen wurden der Übertragungsfaktor, der Linearitäts-, Hysterese- und Kriechfehler sowie die Wiederholbarkeit bestimmt. Die Einflüsse des Verbundwerkstoffes und der Temperatur wurden ebenso untersucht wie verschiedene Technologien zur elektrischen Kontaktierung von Kohlenstoff-Filamentgarn.

Two-layer flexure beams often serve as basic transducers in actuators and sensors. In this paper a generalized description of their stimuli-influenced mechanical behavior is derived. For small deflection angles this description includes a multi-port circuit or network representation with lumped elements for a beam part of finite length. A number of coupled finite beam parts model the dynamic behavior including the first natural frequencies of the beam. For piezoelectric and piezomagnetic interactions, reversible transducer models are developed. The piezomagnetic two-layer beam model is extended to include solenoid and planar coils. Linear network theory is applied in order to determine network parameters and to simplify the circuit representation. The resulting circuit model is the basis for a fast simulation of the dynamic system behavior with advanced circuit simulators and, thus, the optimization of the system. It is also a useful tool for understanding and explaining this multi-domain system through basic principles of general system theory.

So far, embedded sensor networks in composites have mostly been used for structure health monitoring. In contrast to that, in the present work a new stand-alone embedded sensor network for load monitoring of a composite component is presented. Design considerations for the manufacturing of a demonstrator as well as measurement results for cyclic loading are discussed. The presented demonstrator comprises two textile manufactured carbon filament yarn strain sensors for measuring the average bending strain of a large area, embedded capacitive keys for manually controlling the load monitoring process, a sensor ASIC for the processing of the measured data as well as a transponder ASIC with an antenna for the wireless transmission of the measured strains to an external reading station.

In this paper a humidity sensor concept is presented which is fully fabricated by inkjet printing. In the first step conductive finger electrodes are inkjet printed on flexible polyimide substrate with a silver neodecanoate based ink. Afterwards a humidity sensitive layer is printed upon using a polymer particle based ink. Two approaches are presented for minimizing the line width of the electrode fingers. The humidity sensitivities of the sensor capacitances are investigated. The results are promising and demonstrate, that inkjet printed sensors are potentially suited for label applications. The achieved sensitivity, repeatability and hysteresis are in acceptable ranges.

The paper presents preliminary numerical and experimental studies of active textile-reinforced thermoplastic composites with embedded sensor-actuator arrays. The goal of the investigations was the assessment of directional sound wave generation capability using embedded sensor-actuator arrays and developed a wave excitation procedure for ultrasound measurement tasks. The feasibility of the proposed approach was initially confirmed in numerical investigations assuming idealized mechanical and geometrical conditions. The findings were validated in real-life conditions on specimens of elementary geometry. Herein, the technological aspects of unique automated assembly of thermoplastic films containing adapted thermoplastic-compatible piezoceramic modules and conducting paths were described.