Focused Session FQ-7
Wireless Body Sensor Networks for Healthcare Applications
ABSTRACTS
FQ-7:IL02 A Wearable Sensing Platform for the Unobtrusive Analysis of Sweat
F. Di Francesco1, F.M. Vivaldi1, A. Dallinger2, D. Santalucia1, A. Bonini1, N. Poma1, D. Biagini1, F. Greco2, 3, 1Department of Chemistry and Industrial Chemistry, University of Pisa, Pisa, Italy; 2Institute of Solid State Physics, Graz University of Technology, Graz, Austria; 3Institute of Biorobotics, Sant'Anna School of Advanced Studies, Pisa, Italy
Wearable sensors may help to track athlete conditions during training and competition, optimize performance and minimize risks of injury. We show a voltammetric sensor platform exploiting laser induced graphene (LIG) electrodes fabricated on a Kapton® foil combined with a paper sampler for sweat analysis. LIG electrodes were fabricated using a CO2 laser on a Kapton foil, and the conductive tracks were protected by an additional kapton layer. The device was used for the analysis for pH, resistance, uric acid, and tyrosine. While tyrosine and uric acid are naturally electroactive, sensor sensitivity to pH was obtained by drop-casting 1 µL of an aqueous solution containing an indoaniline derivative (4-((4-aminophenyl)imino)-2,6-dimethoxycyclohexa-2,5dien-1-one). A silver/silver chloride reference electrode was integrated in the device by electrodepositing silver on LIG from a silver nitrate solution thanks to the application of a negative voltage (-2 V) and a subsequent treatment with sodium hypochlorite. The reference electrode was finally coated with a Nafion® layer to prevent degradation. The device was calibrated using square wave voltammetry as transduction technique.
FQ-7:IL04 Textile-based Deformation and Flexion Sensors for Motion Analysis and Human Machine Interaction
A. Tognetti, Dipartimento di Ingegneria dell’Informazione, University of Pisa, Pisa, Italy
The possibility to assess human motion and activity during daily living would represent a breakthrough in the biomedical research. In this context, textile-based sensors are a valid alternative with respect to conventional solid-state sensors thanks to their flexibility, low cost, low-weight, and possibility to be adapted to different body structures and unconventional shapes. The present work deals with the physical principles, the design, the characterization and the application of textile-based deformation and flexion sensors. This class of sensors employs piezoresistive materials to build mono- or bi- layer sensing textiles able to detect angular flexion or strain and pressure. We will present applications of textile goniometers for joint angle estimation useful for rehabilitation and human robot interaction. We will also present the development of pressure sensing textiles surface with many applications spanning from human gait analysis to physiological monitoring and sleep monitoring.
FQ-7:IL05 Embedded Sensing by 3D Multi-material Printing
G. Krijnen, A. Dijkshoorn, M. Schouten, D. Kosmas, G. Wolterink, Robotics and Mechatronics Dept., University of Twente, Enschede, The Netherlands
Over the last decade the interest in 3D printing of functional structures, rather than rapid prototyping of non-functional structures, has seen a considerable increase. Meanwhile for various 3D printing technologies the possibility to fabricate and embed sensors has been demonstrated. For mechanical sensing principles that seem rather suitable for 3D multi-material printing include piezo-resistive and capacitive sensing, although piezo-electric, optic and many others have been shown as well. Next to mechanical sensing also bio-potential, chemical, and magnetic sensors have been demonstrated, alongside 3D printed batteries. In our lab we investigate a variety of research questions related to 3D printed functional structcures: characterisation and optimisation of conductivity in 3D printed materials, modelling and characterisation of anisotropic behaviour of 3D printed conductors, understanding and counteracting nonlinearities in sensor performance, applications of 3D printed sensors in biopotential measurements, interaction sensing, flow-sensing, beam deflection control, thrust control, etc. In this presentation I will describe both developments in the field as well examples of our own work.
FQ-7:IL07 Non-invasive Daily Diagnostics through Printed Sensor Technology
M.P.M. Jank, Fraunhofer Institute for Integrated Systems and Device Technology, Thin-Film Systems Group, Erlangen, Germany
Mobile, continuous monitoring of patient health parameters allows for individualized therapies. The example of blood glucose as a control quantity for targetted insuline delivery can be expanded for other diseases upon the availability of adequate sensing systems and therapeutic protocols. Online monitoring further allows for extended self- and home-care schemes and reduced contact to health infrastructure. The acceptance of additional surveillance is significantly higher in case of non-invasive diagnostics. A considerable amount of novel health applications may supplement the classical medical laboratory in future. The requirements for bespoke systems are a precision meeting the high standards of analytical tools in appropriate analytical ranges as well as real-time capabilities. Furthermore, small form factors, low-cost fabrication as achieved by printing techniques and easy operation are prerequisites for a good acceptance by patients and medical staff. Application integration demands for mobile and connective systems. The presentation will give an overview of principles, fabrication, system integration, and use cases of body-worn sensing devices with a focus on printed biochemical sensors.
FQ-7:IL08 InnoRetVision - A new Research Training Group on Innovative Retinal Interfaces for Optimized Artificial Vision funded by the German Research Foundation
W. Mokwa1, P. Walter2, S. Ingebrandt1, RWTH Aachen University 1Institute of Materials in Electrical Engineering I, Aachen, Germany; 2Department of Ophthalmology, University Hospital, Aachen, Germany
Up to now, the results of more than 350 implanted systems based on electrical stimulation of retinal nerve cells are very limited. Even though in nearly all blind patients basic visual functions such as the localization of light spots were registered, reading and recognizing faces were not achieved. Current available technologies seem to be not suitable to obtain a clinical relevant benefit for all patients. The Research Training Group will perform basic research on major topics of local retinal or cortical stimulation with the aim to overcome the limitations of the currently available implant technology. The biological implications originating from retinal remodeling during the degeneration process or functional cortical rearrangements associated with long-term blindness will be adressed. The RTG has three working areas: A evaluates the next generation of stimulation and recording electrode; B contributes to system components for retinal implants; C helps for a further understanding retinal degeneration and improving surgical interventions. At the same time the RTG will provide strong interdisciplinary teaching in the fields of Electrical Engineering, Biophysics, Material Sciences, Neurobiology, Image Processing, and Ophthalmology, especially Vitreoretinal Surgery.
FQ-7:IL09 Printed Wearable Metasurfaces for Wireless On-body Sensors
S. Genovesi, F. Costa, A. Tognetti, Dipartimento di Ingegneria dell’Informazione, University of Pisa, Pisa, Italy
Wearable technology is among the most revolutionary and rapid-growing areas that promise high-potentialities in coping with many demanding challenges related to healthcare management, personal safety, and consumer products enhancement. The widespread employment of body wearables is limited due to intrinsic limitations mainly related to a rigid and wired interface as well as mechanical and electrical critical reliability. Seamless integration is the key factor that our study wants to pursue to achieve user acceptance and to overcome the current limitations of body sensors. To achieve unobtrusive monitoring of body parameters printed and flexible on-body sensing metasurfaces are currently investigated. The proposed metasurfaces are totally passive and consist of a set of identical resonators arranged in a periodic lattice able to be integrated into a garment. The shape of the unit element, the lattice periodicity as well as the materials employed for the realization are the fundamental parameters for shaping the metasurface frequency response which encodes the sensing function. The use of a periodic surface guarantees a strong reflected signal with a prominent resonant peak which is much easier to detect in a challenging environment as the on-body applications.