Periodic Reporting for period 3 - WEAFING (Wearable Electroactive Fabrics Integrated in Garments)
Période du rapport: 2022-07-01 au 2023-12-31
The main goal of this project was to develop novel, unprecedented textiles for garments that provide haptic stimulation. Being textile materials, they open new ways of designing wearable haptics and can be easily integrated into fabrics and garments. They use low voltages, are silent, lightweight, soft and pliable. Other than vibration motors, this haptic textile accesses receptors of our tactile sensory system that react on soft pressure or stroke.
The basis for these garments are textile muscles made from electromechanically active polymers (EAPs). When low voltage is applied to EAP coated yarns, they contract or elongate depending on the polarity of the applied voltage. Processing these yarns further into textiles multiplies the effect of the contraction and/or delivered force, depending on the textile construction used (weave or knit).
We foresee a huge range of applications in haptic garments: in ergonomics, motor learning in sports, wellness, or rehabilitation, for enhancement of virtual reality in gaming or for training purposes, for people with visual impairment, for stress reduction, social communication, and more.
One result of the project is a demonstrator showing the potential of the textiles developed for garments with haptic stimulation. A relevant use case of mediated social touch served as concept for the demonstrator. Studies of human perception allowed to derive requirements for the textiles. The textile development spaned from production of electroactive yarns to processing these into textiles. Finally, the fabrication of the demonstrator sleeve required the integration of textile, electrical connectivity, sensors and dedicated control.
The basis for these garments are textile muscles made from electromechanically active polymers (EAPs). When low voltage is applied to EAP coated yarns, they contract or elongate depending on the polarity of the applied voltage. Processing these yarns further into textiles multiplies the effect of the contraction and/or delivered force, depending on the textile construction used (weave or knit).
We foresee a huge range of applications in haptic garments: in ergonomics, motor learning in sports, wellness, or rehabilitation, for enhancement of virtual reality in gaming or for training purposes, for people with visual impairment, for stress reduction, social communication, and more.
One result of the project is a demonstrator showing the potential of the textiles developed for garments with haptic stimulation. A relevant use case of mediated social touch served as concept for the demonstrator. Studies of human perception allowed to derive requirements for the textiles. The textile development spaned from production of electroactive yarns to processing these into textiles. Finally, the fabrication of the demonstrator sleeve required the integration of textile, electrical connectivity, sensors and dedicated control.
Demonstrator: From relevant use cases identified by market research, online surveys, and involvement of our Advisory Board. the consortium selected the use case of social touch. To show the potential of the developed technology, a social touch sleeve was developed as demonstrator. During video conferencing users can send each other social touches with the sleeves.
Human perception: We explored the perception of textile muscles. Findings on tactile threshold, tactile spatial summation, tactile funneling, tactile apparent motion, experience of pressure stimuli and aging were translated into requirements for textile actuators. The demonstrators were evaluated in human participant user studies in a relevant application environment.
Actuation technology: The electroactive textiles developed that can be actuated with low voltage are a new class of actuators. Before WEAFING, the working principle was shown for knitted textile coated with EAP in aqueous salt solution. Current progress is that we have developed the first woven fabrics that move in air. The transition from passive to mechanically active structure is a paradigm shift for the textile community that requires new textile constructions. We have for the first time demonstrated that in-air, in-fabric actuated fabrics can be woven on real warped looms. We have developed weaving techniques that enable handling of the yarns while maintaining the integrity of the fabric. We have also developed new knitting techniques for handling actuating yarns.
Electroactive yarns: We made yarn actuators by coating commercial yarns with EAPs and optimised them. The performance was considerably enhanced as compared to the pre-WEAFING yarn actuators: in liquid actuation at 0.075% strain in 800s and 8 mN force). As a WEAFING outcome, we have now obtained fast (<1s ) actuation at 1.5% strain in liquid.
With a pilot line we are now able to produce coated yarns on the production scale of kilometres. Furthermore, these yarns were tested for handling in standard textile production machines. These are two important steps towards productification that have been achieved.
In addition to the in-air yarns based on the coiled yarns coated with the ionogels, we have also developed a new yarn actuator type that moves in air: tape yarns as a layered structure. As a WEAFING outcome, we have made small scale production of such tape yarns (1600 produced during WEAFING) that have been woven in fabrics, and used in the project demonstrator sleeve.
Ionogel development:
We developed new UV curable ionogels: a first generation of "wet" ionogels with present state-of-the-art ionic conductivities (from 10-4 to above 10-3 S/cm) and suitable mechanical properties (stretchability > 80%), and a second generation of "dry" ionic coatings which present state-the-art ionic conductivities (>10-5 S/cm), stretchability above 90% and are washable with dry-cleaning solvent.
For both, dynamic bond chemistry into the ionogel structures was introduced allowing unprecedented features such as self-healing of the ionic coatings, welding/co-bonding of two already polymerized coatings and recycling, which support better sustainability of smart textiles, have been only scarsely reported in the literature before WEAFING and never for smart textiles to the best of our knowledge.
Yarn actuators coated with these ionogels can move in air showing 0.3% strain and 3 mN force at 120s.
Two important steps achieved toward productification are: for the up-scaling we have constructed a pilot line allowing to produce ionoyarns on the order of kilometres. We also tested yarns for handling in standard textile production machines.
Communication: We developed a multi-media communication and dissemination plan. It tackles scientific peers, industries, in development and applications (Inclusion, Ergonomics, Sports, Medical, Gaming, Labour, Communication, Art/Fashion, and Safety) and end consumers to address market pull and technology push innovation. Over time over 300 live and virtual/online communication and dissemination activities (conferences, workshops, lectures, exhibitions, (scientific) publications, social media posts, videos, press releases, interviews) were received by tens of thousands of people and a potential of millions. So far, a patent analysis uncovered few to none technically similar patents. Some industrial stakeholders already reached out to the consortium for collaboration.
Human perception: We explored the perception of textile muscles. Findings on tactile threshold, tactile spatial summation, tactile funneling, tactile apparent motion, experience of pressure stimuli and aging were translated into requirements for textile actuators. The demonstrators were evaluated in human participant user studies in a relevant application environment.
Actuation technology: The electroactive textiles developed that can be actuated with low voltage are a new class of actuators. Before WEAFING, the working principle was shown for knitted textile coated with EAP in aqueous salt solution. Current progress is that we have developed the first woven fabrics that move in air. The transition from passive to mechanically active structure is a paradigm shift for the textile community that requires new textile constructions. We have for the first time demonstrated that in-air, in-fabric actuated fabrics can be woven on real warped looms. We have developed weaving techniques that enable handling of the yarns while maintaining the integrity of the fabric. We have also developed new knitting techniques for handling actuating yarns.
Electroactive yarns: We made yarn actuators by coating commercial yarns with EAPs and optimised them. The performance was considerably enhanced as compared to the pre-WEAFING yarn actuators: in liquid actuation at 0.075% strain in 800s and 8 mN force). As a WEAFING outcome, we have now obtained fast (<1s ) actuation at 1.5% strain in liquid.
With a pilot line we are now able to produce coated yarns on the production scale of kilometres. Furthermore, these yarns were tested for handling in standard textile production machines. These are two important steps towards productification that have been achieved.
In addition to the in-air yarns based on the coiled yarns coated with the ionogels, we have also developed a new yarn actuator type that moves in air: tape yarns as a layered structure. As a WEAFING outcome, we have made small scale production of such tape yarns (1600 produced during WEAFING) that have been woven in fabrics, and used in the project demonstrator sleeve.
Ionogel development:
We developed new UV curable ionogels: a first generation of "wet" ionogels with present state-of-the-art ionic conductivities (from 10-4 to above 10-3 S/cm) and suitable mechanical properties (stretchability > 80%), and a second generation of "dry" ionic coatings which present state-the-art ionic conductivities (>10-5 S/cm), stretchability above 90% and are washable with dry-cleaning solvent.
For both, dynamic bond chemistry into the ionogel structures was introduced allowing unprecedented features such as self-healing of the ionic coatings, welding/co-bonding of two already polymerized coatings and recycling, which support better sustainability of smart textiles, have been only scarsely reported in the literature before WEAFING and never for smart textiles to the best of our knowledge.
Yarn actuators coated with these ionogels can move in air showing 0.3% strain and 3 mN force at 120s.
Two important steps achieved toward productification are: for the up-scaling we have constructed a pilot line allowing to produce ionoyarns on the order of kilometres. We also tested yarns for handling in standard textile production machines.
Communication: We developed a multi-media communication and dissemination plan. It tackles scientific peers, industries, in development and applications (Inclusion, Ergonomics, Sports, Medical, Gaming, Labour, Communication, Art/Fashion, and Safety) and end consumers to address market pull and technology push innovation. Over time over 300 live and virtual/online communication and dissemination activities (conferences, workshops, lectures, exhibitions, (scientific) publications, social media posts, videos, press releases, interviews) were received by tens of thousands of people and a potential of millions. So far, a patent analysis uncovered few to none technically similar patents. Some industrial stakeholders already reached out to the consortium for collaboration.
In the project we developed the first textile that can be actuated with low voltage. Before WEAFING, the working principle was shown for knitted textile coated with EAP in aqueous salt solution. During the project we have developed the first woven fabrics that move in air.
Whereas perception is well studied for vibration motors, it is not for pressure. We have developed devices that allows for systematic exploration of the relation between force and perception.
Concerning results and impact, WEAFING progresses smart systems and (soft) robotics by developing multifunctional electroactive fabrics, using textile fabrication where sensors and actuators are woven or knitted into the fabric. A new form of smart material and new digitized products such as wearable haptic displays will be made possible. The research field of psychophysics did progress by new results for perception of touch. The electroactive fabrics will enable new ways to design smart garments, for applications ranging from health to inclusion, from remote communication to entertainment, and further also for exoskeleton-like suits, or applications in automotive or interior design. With the developed textile actuators and advanced textile fabrication methods, WEAFING generates new opportunities for European textile and smart material industries.
Whereas perception is well studied for vibration motors, it is not for pressure. We have developed devices that allows for systematic exploration of the relation between force and perception.
Concerning results and impact, WEAFING progresses smart systems and (soft) robotics by developing multifunctional electroactive fabrics, using textile fabrication where sensors and actuators are woven or knitted into the fabric. A new form of smart material and new digitized products such as wearable haptic displays will be made possible. The research field of psychophysics did progress by new results for perception of touch. The electroactive fabrics will enable new ways to design smart garments, for applications ranging from health to inclusion, from remote communication to entertainment, and further also for exoskeleton-like suits, or applications in automotive or interior design. With the developed textile actuators and advanced textile fabrication methods, WEAFING generates new opportunities for European textile and smart material industries.