Invited speaker: Evy Reiske

Title of Presentation: Smart Textiles in Defence: Opportunities and challenges

Smart Textiles present various opportunities for military applications, such as enhancing communication, camouflage, health monitoring, and energy management. These technologies promise to elevate defence operations through real-time data integration and adaptive technologies. However, challenges arise which must be addressed. This presentation provides a concise overview of the potential and hurdles associated with smart textiles in defence, offering insights into successful integration strategies.

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Further Presentations:

Influence of Washing Cycles on the Electrical Conductivity of Screen Printed Circuits Pauline Stockmann, Katarzyna Wójkowska, Jerzy Szałapak, Sigrid Rotzler, Elisabeth Eppinger – Fraunhofer IZM

Electronic textiles (e-textiles) offer comfortable solutions for many body-worn sensor needs. This requires them to be washable, which remains a challenging feat—yet indispensable for reliable, and in turn more sustainable products. Printed circuits combine layout flexibility and established processes, making them highly relevant for e-textile developers. In this work, screen printed silver-based pastes are tested towards their washability and analyzed using statistical methods. Different materials, layout and substrates are tested to establish which parameters can affect washing performance. The samples are exposed to 20 wash cycles and other reliability tests. While directly printed samples fail quickly, other configurations show good washability. The results of the study provide valuable insights for highly robust printed e-textiles.

Design and Realisation of an Electronic System Capable of Analyzing the Mechanical Impact of the Washing Process on E-Textiles Thomas Van Acker, Frederick Bossuyt, Pieter Bauwens – Ghent University

The integration of electronics with textiles, known as etextiles, has created smart garments and accessories that enhance daily life. However, their low washability due to easy breakage of electronic components and connections hinders their adoption. This study addresses this challenge by developing an electronic system, called SARDINE, to measure the mechanical impact of washing on e-textiles. The SARDINE system consists of nodes with IMU sensors and conductive yarns that measure mechanical stresses during washing. The study presents the development, testing, and analysis of the SARDINE system, providing insights into the mechanical impact of washing on e-textiles and informing the design of more durable and washable e-textiles. The developed system will facilitate the widespread adoption of e-textiles by enabling the creation of more reliable and long-lasting smart garments and accessories.

Mechanical Reliability of Multifunctional E-Yarns under Bending and Torsional Fatigue Tharushi Peiris, Lukas Werft, Sigrid Rotzler, Arash Shahidi, Malindu Ehelagasthenna, Kalana Marasinghe, Carlos Oliveira, Tilak Dias, Theodore Hughes Riley – Nottingham Trent University

Electronic yarns (E-yarns) are a type of electronic textile where electronics are embedded into a yarn-like structure before being incorporated into a larger textile or garment. The mechanical reliability of E-yarns is critical for their successful integration into smart textile systems. This study examines the durability of E-yarns incorporating light emitting diodes (LEDs), photodiodes (PDs), resistors, and vibrotactile actuators under cyclic bending and torsional stresses. The E-yarns were fabricated through a standardised three stage process involving the soldering of the active components onto Litz wires, the encapsulation of the component and solder connections, and using braiding to cover the component and wires, where the exact structure of the Eyarns would vary depending on the embedded component type. Fatigue testing was conducted using an Instron ElectroPuls E10000 system to assess bending (45° folding and 135° unfolding angles at frequencies of 0.5 Hz and 1 Hz) and torsional (250° angle at 0.5 Hz frequency) deformation. Electrical measurements were recorded to evaluate functional degradation of the samples. Overall the E-yarns were robust to repeating bending and twisting, however failures were observed for some E-yarn types. Structural degradation tended to be localised within the Litz wires, particularly at yarn segments adjacent to the encapsulation region, where mechanical stress concentrations are highest. These trends are supported by X-ray imaging and SEM analysis.

Reliability of Textile Integrated Circuits: Strategies Towards an Increased Robustness Sigrid Rotzler, Christine Kallmayer, Malte von Krshiwoblozki – Technical University Berlin

Electronic textiles (e-textiles) merge electronic functionality with textile comfort. The textile integration results in reliability requirements for the added components. Mechanical stresses pose a large challenge and can lead to defects and damages. The textile circuit board is especially vulnerable. In order to increase the robustness and long-term reliability, different strategies for two different types of textile circuits—based on insights from previous research—were explored towards their effectiveness, while trying to keep unwanted effects like an increase in electrical resistance to a minimum. The results show that changes in circuit layout, processing parameters and protective structures can lead to a significant increase in mechanical properties of the circuits. The insights of the presented research will aide in making etextiles more robust.

Performance Evaluation of a Multi-Site E-Textile Temperature Monitoring System for Navigating Exercise Md. Saiful Hoque, Baptiste Garnier, Mathys Mulot Hauriez, Antonio Bandur, Cédric Cochrane, Vladan Koncar, Azadeh Yadollahi – University of Toronto

The feasible way of monitoring core body temperature is essential for exercise safety and performance, yet current non-invasive methods remain limited. This study evaluates the accuracy of thermistor-equipped e-textile for estimating core body temperature via skin temperature at four anatomical sites (hand, upper arm, forearm, chest) during exercise, using ingestible temperature pills as the reference standard. Results show substantial differences between skin and core body temperature (mean absolute error: 8.3– 9.9°C), with the right upper arm providing the closest correlation across participants (r = 0.55–0.78). While direct skin temperature readings cannot substitute for core measurements, temporal changes at the upper arm and hand best reflect skin temperature trends. These findings highlight the importance of sensor placement and suggest that advanced algorithms and multi-site integration are needed to improve non-invasive core temperature estimation in wearable systems.

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