Journal Papers
| 1. | Ahmed, Ibrahim Adel Khamis; Cetin, Munire Sibel; Ozlem, Kadir; Atalay, Asli Tuncay; Ince, Gökhan; Atalay, Ozgur: From Knitting Technology to Robotics: Untethered Thermally Actuated Textile Exoskeleton for Dexterity Applications. In: Advanced Science, pp. e09870, Forthcoming. (Abstract | Links | BibTeX)@article{ahmet2025Thermally,Abstract Soft wearable robotic devices offer significant potential for human mobility assistance and rehabilitation; however, existing solutions are often hindered by bulkiness, limited scalability, and restricted portability. This study introduces a textile-based exoskeleton glove equipped with thermally driven actuators, achieving dexterous motion in under 12 s using only 10.8 W of power while maintaining a low operating temperature of 48 °C. This performance surpasses the fastest previously reported system in terms of power input and operating temperature, which achieved actuation in 10 s but required 15 W and operated at 100 °C. In comparison, recent studies report response times of 120 s, with 14 W consumption and temperatures near 95 °C. The actuators utilize low-boiling-point liquids that undergo phase transitions upon heating, enabling fast, untethered actuation without external systems. The seamless knitted structure integrates sensing and actuation functionalities, including self-return to initial position capability. This is achieved through digital machine knitting of specific patterns using functional yarns. The actuators demonstrate 270° bending, generating 2 N gripping force while maintaining energy consumption efficiency. The glove is mountable on an industrial robotic arm, demonstrating its ability to grasp and relocate objects. This study presents a quick-response, scalable, energy-efficient solution for wearable robotics. |
| 2. | Ozlem, Kadir; Atalay, Asli Tuncay; Atalay, Ozgur; Ince, Gökhan: FogETex: Fog Computing Framework for Electronic Textile Applications. In: IEEE Internet of Things Journal, vol. 12, no. 6, pp. 6856-6874, 2025. (Abstract | Links | BibTeX)@article{Ozlem2025IEEE,Textile products are present in almost every aspect of human life. With the introduction of electronic textiles (e-textiles), textile products have become capable of converting various physiological and environmental stimuli into electrical signals, many of which are of vital importance to humans. Therefore, these products require real-time (low-latency) and robust computing systems. However, due to comfort considerations, they cannot accommodate powerful computing resources. In this study, a novel fog computing-based framework (FogETex) is proposed to meet the needs of e-textile applications. FogETex is a Platform-as-a-Service model that is cross-platform supported, scalable, and operates in real time. This framework encompasses end-to-end integration of the system, including Textile-based Internet of Things (T-IoT) device, fog devices, and the cloud. Fog devices consist of a broker that manages the fog node and a worker that handles incoming computation requests. Sensor data is transmitted to the fog node through a mobile application, and system architecture can be monitored through developed user interfaces. Resource usage from broker devices is monitored in real time to prevent worker devices from experiencing overload. For the system case study, a deep-learning-based gait phase analysis application using textile-based capacitive sensors is employed. FogETex was evaluated in terms of time characteristics, resource usage, and network bandwidth usage using a mock client to determine the ideal system performance and an actual client to conduct real-world tests. The fog devices outperformed the cloud system in these metrics. Besides being developed primarily for e-textile applications, the FogETex framework can accommodate other IoT devices as well. |
| 3. | Kocak, Emine Dilara; Gumus, Cagatay; Ozlem, Kadir; Operamolla, Alessandra; Dammacco, Giada; Pagliai, Filippo; Pala, Nursema; Atalay, Ozgur: Sustainable Hydrogels from Okra Stem Waste for Biosignal Detection and Sensor Technologies. In: ACS Sustainable Resource Management, vol. 2, no. 3, pp. 501-513, 2025. (Abstract | Links | BibTeX)@article{Kocak2025,Recent advancements in wearable technology have driven the need for flexible and biocompatible materials that can seamlessly interface with soft, water-rich biological tissues. Traditional petroleum-based polymers often lack compatibility with conductive materials, limiting their use in bioelectronics. In contrast, hydrogels, with their softness, flexibility, and mechanical similarity to biological tissues, offer a promising alternative due to their ecological benefits and adaptability. Here, we present the development of sustainable hydrogels derived from okra stem mucilage, a renewable agricultural waste, to address challenges in bioelectronics. By integrating gelatin for improved adhesion and succinic acid as a crosslinking agent, we achieved significant enhancements in the hydrogels’ mechanical, electrical, and antibacterial properties. The inclusion of 10% succinic acid increased tensile strength by 95% and Young’s modulus by 93%, while electrical conductivity rose from 0.6 S/m to 1.8 S/m. The hydrogels demonstrated robust adhesion to diverse substrates, including glass, pigskin, and paper, with the highest adhesion strength of 57.3 kPa recorded on paper. Capacitive sensors fabricated using these hydrogels exhibited a maximum relative capacitance change of 1.42 under mechanical strain, and their application as ECG electrodes provided signals comparable to commercial alternatives. These findings establish okra-gum-based hydrogels as a promising platform for sustainable, high-performance materials in wearable bioelectronics, including smart health monitoring and human-computer interaction systems. |
| 4. | Ozlem, Kadir; Gumus, Cagatay; Yilmaz, Ayse Feyza; Atalay, Asli Tuncay; Atalay, Ozgur; Ince, Gökhan: Cloud-based Control System with Sensing and Actuating Textilebased IoT Gloves for Telerehabilitation Applications. In: Advanced Intelligent Systems, vol. 7, iss. 8, pp. 2400894, Forthcoming. (Abstract | Links | BibTeX)@article{Ozlem2025,Remote manipulation devices extend human capabilities over vast distances or in inaccessible environments, removing constraints between patients and treatment. The integration of therapeutic and assistive devices with the Internet of Things (IoT) has demonstrated high potential to develop and enhance intelligent rehabilitation systems in the e-health domain. Within such devices, soft robotic products distinguish themselves through their lightweight and adaptable characteristics, facilitating secure collaboration between humans and robots. The objective of this research is to combine a textile-based sensorized glove with an air-driven soft robotic glove, operated wirelessly using the developed control system architecture. The sensing glove equipped with capacitive sensors on each finger captures the movements of the medical staff's hand. Meanwhile, the pneumatic rehabilitation glove designed to aid patients affected by impaired hand function due to stroke, brain injury, or spinal cord injury replicates the movements of the medical personnel. The proposed artificial intelligence-based system detects finger gestures and actuates the pneumatic system, responding within an average response time of 48.4 ms. The evaluation of the system further in terms of accuracy and transmission quality metrics verifies the feasibility of the proposed system integrating textile gloves into IoT infrastructure, enabling remote motion sensing and actuation. |
| 5. | Al-azzawi, Nada; Yunculer, Irem; Ozlem, Kadir; Cetin, Munire Sibel; Atalay, Asli Tuncay; Atalay, Ozgur; Ince, Gökhan: Textile-based Low-frequency RC Filter for Noise Reduction in ECG Signals. In: Global Challenges, vol. 9, no. 3, pp. 2400237, 2025. (Abstract | Links | BibTeX)@article{Nada2025,Advancements in electronic textiles over the past decade have significantly transformed the field of wearable technology, with recent developments leading to the production of a wide array of textile-based sensing and actuation systems. Beyond sensors and actuators, textile-based technologies can benefit from the integration of additional electronic solutions within the framework of textilization. One such solution is filtering, which has primarily been explored in the context of high-frequency applications in e-textiles. In contrast, low-frequency filtering has received limited attention in the literature. This study investigates the design and fabrication of low-frequency textile-based Resistor–Capacitor (RC) filters, emphasizing their potential for wearability. Various materials and geometric configurations are explored for the resistive and capacitive components of the filter, evaluating their performance in terms of frequency response. Additionally, these filters are integrated with textile-based electrodes and assess their filtering efficacy at a cutoff frequency of approximately 100 Hz within the context of an electrocardiogram (ECG) application during both static and dynamic activities. The results demonstrate that textile-based filters can serve as viable alternatives to conventional electronic filters, exhibiting comparable performance in noise suppression, as evidenced by signal-to-noise ratio (SNR) improvements of 25 dB during static activities and 11 dB during dynamic activities. |
| 6. | Yilmaz, Ayse Feyza; Ozlem, Kadir; Celebi, Mehmet Fatih; Taherkhani, Bahman; Kalaoglu, Fatma; Atalay, Aslı Tunçay; Ince, Gokhan; Atalay, Ozgur: Design and Scalable Fast Fabrication of Biaxial Fabric Pouch Motors for Soft Robotic Artificial Muscle Applications. In: Advanced Intelligent Systems, vol. 6, no. 8, pp. 2300888, 2024. (Abstract | Links | BibTeX)@article{Yilmaz2024Pouch,Soft pouch motors, engineered to mimic the natural movements of skeletal muscles, play a crucial role in advancing robotics and exoskeleton development. However, the fabrication techniques often involve multistage processes; they lack soft sensing capabilities and are sensitive to cutting and damage. This work introduces a new textile-based pouch motors with the capacity for biaxial actuation and capacitive sensory functions, achieved through the application of computerized knitting technology using ultrahigh molecular weight polyethylene yarn (Spectra) and conductive silver yarns. This method enables the rapid and scalable mass fabrication of robust pouch motors. The resulting pouch motors exhibit maximum lifting capacity of 10 kg, maximum contraction of 53.3% along the y-axis, and transverse extension of 41.18% along the x-axis at 50 kPa pressure. Finite element analysis closely matches the experimental data. The capacitance signals in relation to contraction motion are well suited for detecting air pressure levels and hold promise for applications requiring robotic control. Notably, it effectively elevates an ankle joint simulator at a 20° angle, highlighting its potential for applications such assisting individuals with foot drop. This study presents a practical demonstration of the soft ankle exosuit designed to provide lifting support for individuals facing this mobility challenge. |
| 7. | Atalay, Ozgur; Ozlem, Kadir; Gumus, Cagatay; Ahmed, Ibrahim Adel Khamis; Yilmaz, Ayse Feyza; Celebi, Mehmet Fatih; Cetin, Munire Sibel; Taherkhani, Bahman; Atalay, Asli Tuncay; Ince, Gökhan: Thermally Driven 3D Seamless Textile Actuators for Soft Robotic Applications. In: Advanced Intelligent Systems, vol. 6, no. 11, pp. 2400133, 2024. (Abstract | Links | BibTeX)@article{Atalay2024,Soft wearable robotic devices have emerged as a promising solution for human mobility assistance and rehabilitation, yet current solutions suffer from issues such as bulkiness, high cost, nonscalability, noise, and limited portability. This study introduces a novel approach to soft robotic assistive devices using untethered, soft actuators with seamlessly integrated sensing, heating, and actuation properties through digital machine knitting and low-boiling liquid. The proposed soft actuator operates under a voltage of less than 12.5 V, generating a tip force of up to 50 mN. This actuator achieves a bending motion when filled with 2 mL of low-boiling liquid and supplied with 15 W. The dynamic response of the actuator is examined under consistent parameters, revealing a 60-second inflation time and a subsequent natural cooling period of 30 s at room temperature. Notably, over 12 cycles, the tip force of the actuator exhibits minimal variation, highlighting its durability for prolonged usage. The proposed approach paves the way for overcoming the limitations of existing technologies, particularly in terms of motion assistance and rehabilitation applications, with an emphasis on at-home usage during daily activities. |
| 8. | Yilmaz, Ayse Feyza; Ozlem, Kadir; Khalilbayli, Fidan; Celebi, Mehmet Fatih; Kalaoglu, Fatma; Atalay, Asli Tuncay; Ince, Gökhan; Atalay, Ozgur: Resistive Self-Sensing Controllable Fabric-Based Actuator: A Novel Approach to Creating Anisotropy. In: Advanced Sensor Research, vol. 3, no. 7, pp. 2300108, 2024. (Abstract | Links | BibTeX)@article{Yilmaz2023Resistive,Designing advanced soft robots with soft sensing capabilities for real-world applications remains challenging due to the intricate integration of actuation and sensor capabilities, which require diverse materials and complex procedures. This paper introduces a fabric-based robotic technology featuring an “all textile-based self-sensing pneumatic actuator” and a low-cost resistive strain sensor created through simple sewing techniques. The novel approach eliminates the need for additional strain-limiting woven fabric, simplifying the manufacturing process. It also enables the development of bioinspired motions such as bending, twisting, and snake-like movements. The electromechanical behaviors of the sensor and bending actuator are tested for their performance under positive air pressure. Through mathematical modeling, the actuator's sensing capacity is estimated accurately, providing precise feedback for pressure and position control. Different closed-loop controller types, including On–Off and Proportional Integral Derivative (PID) control, are evaluated for their effectiveness. Furthermore, the practical application of the sensing actuator is demonstrated by integrating it into a wearable glove, showcasing its enhanced sensing capabilities for finger-like soft wearable robotic applications. This research tackles the challenges associated with designing advanced soft robots with integrated sensing capabilities, offering a promising fabric-based solution that can drive significant advancements in real-world applications. |
| 9. | Yilmaz, Ayse Feyza; Ahmed, Ibrahim Adel Khamis; Gumus, Cagatay; Ozlem, Kadir; Cetin, Munire Sibel; Atalay, Asli Tuncay; Ince, Gökhan; Atalay, Ozgur: Highly Stretchable Textile Knitted Interdigital Sensor for Wearable Technology Applications. In: Advanced Sensor Research, vol. 3, no. 2, pp. 2300121, 2024. (Abstract | Links | BibTeX)@article{yilmaz2024Interdigital,Wearable technology applications have experienced remarkable development and advancements, with soft and stretchable strain sensors playing a significant role in this progress. Despite the promising potential of combed-shaped interdigital capacitive strain sensors in wearable electronics, several challenges exist, including limited stretchability, universal mass fabrication, and seamless integration into diverse clothing parts. This study presents a textile knitted interdigital capacitive sensor that incorporates stretchable conductive yarn, produced using textile twisting technology, to achieve stretchability and adaptability, allowing seamless conformation to human body movements and textile materials. The fabrication process involves embedding the interdigital electrodes and interconnections directly into the fabric through textile knitting technology, ensuring robust integration. Furthermore, this work presents opportunities for commercializing the stretchable interdigital strain sensor through a low-cost and mass production strategy. Electromechanical characterization demonstrates exceptional performance with high stretchability (≈230%), excellent linearity (R2 = 0.997), a gauge factor (GF) of −0.68 representing relative capacitance change, and a rapid response time of 66 ms. To validate the usability of sensors in wearable technology, a knee brace application is employed to investigate capacitance changes during walking and cycling exercises. This approach will accelerate the accessibility of wearable stretchable interdigital sensors for all. |
| 10. | Ayvaz, Ugur; Ozlem, Kadir; Yilmaz, Ayse Feyza; Atalay, Asli Tuncay; Atalay, Ozgur; Ince, Gökhan: Real-Time Stride Length Estimation Using Textile-Based Capacitive Soft Strain Sensors. In: IEEE Transactions on Instrumentation and Measurement, vol. 73, pp. 1-11, 2024. (Abstract | Links | BibTeX)@article{Ayvaz2023,Stride length estimation (SLE) is a fundamental component of pedestrian dead reckoning (PDR) in indoor navigation and positioning (INP) applications. The knowledge of stride length is crucial for determining the distances covered by pedestrians and estimating their position in real time. In this study, we proposed a real-time SLE method using innovative textile-based capacitive strain sensors (TCSSs) attached to knee pads. The SLE performance of the capacitive sensors was compared with smartphone inertial measurement units (IMUs), and the results were reported. We applied a supervised SLE approach by creating labeled gait data from participants who wore sensors and walked along controlled paths created with predetermined stride lengths. An adaptive stride detection (ASD) algorithm was developed to handle data diversity resulting from varying participant characteristics. Furthermore, we investigated the contribution of gait phase features (GPFs) to SLE. The proposed model achieved impressive outcomes with a mean absolute error (MAE) of 8.73 cm, showcasing its significance in accurate real-time SLE. |
| 11. | Yilmaz, Ayse Feyza; Khalilbayli, Fidan; Ozlem, Kadir; Elmoughni, Hend M.; Kalaoglu, Fatma; Atalay, Asli Tuncay; Ince, Gökhan; Atalay, Ozgur: Effect of Segment Types on Characterization of Soft Sensing Textile Actuators for Soft Wearable Robots. In: Biomimetics, vol. 7, no. 4, 2022, ISSN: 2313-7673. (Abstract | Links | BibTeX)@article{feyzayilmaz2022,The use of textiles in soft robotics is gaining popularity because of the advantages textiles offer over other materials in terms of weight, conformability, and ease of manufacture. The purpose of this research is to examine the stitching process used to construct fabric-based pneumatic bending actuators as well as the effect of segment types on the actuators’ properties when used in soft robotic glove applications. To impart bending motion to actuators, two techniques have been used: asymmetry between weave and weft knit fabric layers and mechanical anisotropy between these two textiles. The impacts of various segment types on the actuators’ grip force and bending angle were investigated further. According to experiments, segmenting the actuator with a sewing technique increases the bending angle. It was discovered that actuators with high anisotropy differences in their fabric combinations have high gripping forces. Textile-based capacitive strain sensors are also added to selected segmented actuator types, which possess desirable properties such as increased grip force, increased bending angle, and reduced radial expansion. The sensors were used to demonstrate the controllability of a soft robotic glove using a closed-loop system. Finally, we demonstrated that actuators integrated into a soft wearable glove are capable of grasping a variety of items and performing various grasp types. |
| 12. | Elmoughni, Hend M.; Atalay, Ozgur; Ozlem, Kadir; Menon, Akanksha K.: Thermoelectric Clothing for Body Heat Harvesting and Personal Cooling: Design and Fabrication of a Textile-Integrated Flexible and Vertical Device. In: Energy Technology, vol. 10, no. 10, pp. 2200528, 2022. (Abstract | Links | BibTeX)@article{elmoughni2022,Textiles offer the ideal platform to develop thermoelectric (TE) clothing for body heat harvesting and personal thermoregulation. Herein, textiles used in everyday clothing are adapted to fabricate a flexible and vertical TE device architecture. Selective laser patterning is used to create cavities for embedding bulk inorganic Bi2Te3 legs into a knitted polyester fabric used in next-to-skin sportswear. The device thermal design is optimized using fabric layering to accommodate longer legs up to 0.8 mm, and a flexible 3D-printed heat sink is integrated to maximize heat dissipation to the ambient. Using flexible copper foil to connect the legs with a low-temperature soldering paste, a stable and ultralow device electrical resistance (<1 Ω) is achieved, which is unprecedented for wearable textile-based TE devices. The developed prototype demonstrates power generation of up to 3.8 μW using body heat, and it provides a cooling effect of 1 °C for personal thermoregulation. Furthermore, the prototype withstands a tensile strain up to 20%, over 1000 bend cycles (at a 23 mm radius comparable with the curvature of the human wrist), and ten wash cycles, thereby demonstrating viability for TE clothing. Strategies for optimization are also presented to enable further performance enhancements using all textile-compatible processes. |
| 13. | Gumus, Cagatay; Ozlem, Kadir; Khalilbayli, Fidan; Erzurumluoglu, Omur Fatmanur; Ince, Gökhan; Atalay, Ozgur; Atalay, Asli Tuncay: Textile-based pressure sensor arrays: A novel scalable manufacturing technique. In: Micro and Nano Engineering, pp. 100140, 2022. (Abstract | Links | BibTeX)@article{gumus2021micro,Soft pressure sensors have sparked a lot of interest over the last decade because of their applications in human motion recognition, object detection, and human–computer interaction. However, their mass production and availability to end users are limited due to the complex and time-consuming steps. The scalability of working range for various applications is also a critical challenge. Therefore, a laborless, rapid, and scalable manufacturing technique for capacitive-based soft pressure sensors with high sensitivity and high working range is proposed in this work. The novel manufacturing method enables manipulation of sensor properties by varying production parameters based on specific application needs. The proposed sensor's electrode is made of conductive knit fabric, and the dielectric layers are made of thermoplastic polyurethane (TPU) sheets. As a result of the novel approach, it is possible to generate scalable air gaps between electrodes and dielectric layers to capture low pressures of less than 1 kPa. The usage of multi-layer TPU sheets also increases the working range of sensors up to 1000 kPa. Here, the proposed technology is successfully applied to create several sensor mats for different purposes such as improved gesture and shape recognition, and interactive gaming mats for children. |
| 14. | Elmoughni, Hend M; Yilmaz, Ayse Feyza; Ozlem, Kadir; Khalilbayli, Fidan; Cappello, Leonardo; Atalay, Asli Tuncay; Ince, Gökhan; Atalay, Ozgur: Machine-Knitted Seamless Pneumatic Actuators for Soft Robotics: Design, Fabrication, and Characterization. In: Actuators, vol. 10, no. 5, pp. 94, 2021. (Abstract | Links | BibTeX)@article{elmoughni2021machine,Computerized machine knitting offers an attractive fabrication technology for incorporating wearable assistive devices into garments. In this work, we utilized, for the first time, whole-garment knitting techniques to manufacture a seamless fully knitted pneumatic bending actuator, which represents an advancement to existing cut-and-sew manufacturing techniques. Various machine knitting parameters were investigated to create anisotropic actuator structures, which exhibited a range of bending and extension motions when pressurized with air. The functionality of the actuator was demonstrated through integration into an assistive glove for hand grip action. The achieved curvature range when pressurizing the actuators up to 150 kPa was sufficient to grasp objects down to 3 cm in diameter and up to 125 g in weight. This manufacturing technique is rapid and scalable, paving the way for mass-production of customizable soft robotics wearables. |
Conference Papers
| 1. | Erzurumluoglu, Omur Fatmanur; Ozlem, Kadir; Atalay, Asli Tuncay; Atalay, Ozgur; Ince, Gökhan: Fog Computing-based Real-Time Emotion Recognition using Physiological Signals. In: 2025 27th International Conference on Advanced Communications Technology (ICACT), pp. 1-9, 2025. (Abstract | Links | BibTeX)@inproceedings{10936760,Emotion recognition based on physiological signals has become a crucial area of research in affective computing and human-computer interaction, with applications in smart homes, workplaces, educational institutions, healthcare, and entertainment. In this study, a real-time emotion recognition system utilizing fog computing architecture was developed by considering the challenges of latency, total response time, resource usage, and security in IoT environments. The random forest machine learning model was trained with time-based statistical features by using the DREAMER dataset. Even though the model achieved an accuracy of 84.21% with 104 features, to meet real-time performance requirements, the system was optimized to calculate 24 features, maintaining a commendable accuracy of 79.70%. Extensive experiments demonstrated the superior performance of fog computing compared to edge and cloud computing in terms of latency, queuing delay, jitter, and most importantly total response time. The results highlight the proposed system’s ability to support multiple users simultaneously. |
| 2. | Celik, Ilknur; Cetin, Munire Sibel; Ozlem, Kadir; Atalay, Ozgur; Atalay, Asli Tuncay; Ince, Gökhan: Gesture Recognition on Textile-Based Pressure Sensor Array. In: 2024 5th International Conference in Electronic Engineering, Information Technology & Education (EEITE), pp. 1-5, 2024. (Abstract | Links | BibTeX)@inproceedings{Celik2024,Wearable technologies are in pursuit of designing portable devices worn by people. In this paper, gesture recognition on a sleeve having a capacitive textile-based pressure sensor array has been developed. Machine learning models are generated to recognize a set of gestures by accumulating capacitance values read from a sensor array during the execution of gestures. The performance of the gesture recognition system is evaluated in the experiments conducted with human test subjects. Real-time gesture prediction is achieved using the trained model. The performed gestures and predicted data are collected and analyzed, resulting in accuracies up to 86%. |
| 3. | Erzurumluoglu, Omur Fatmanur; Ozlem, Kadir; Tunc, Hande; Gumus, Cagatay; Khalilbayli, Fidan; Buyukaslan, Ahsen; Yilmaz, Hurriyet; Atalay, Asli Tuncay; Atalay, Ozgur; İnce, Gökhan: Pressure Monitoring for Scoliosis Braces using Textile-based Pressure Sensor Arrays. In: HCist - International Conference on Health and Social Care Information Systems and Technologies 2023, pp. 1409-1416, Procedia Computer Science, 2024, ISSN: 1877-0509, (HCist - International Conference on Health and Social Care Information Systems and Technologies 2023). (Abstract | Links | BibTeX)@inproceedings{Erzurumluoglu2024,Scoliosis is a type of spine deformity that commonly arises during adolescence. The usage of a brace is an effective method in the conservative treatment of scoliosis. The aim of this study is to examine the pressure applied to the brace that is used in the treatment of scoliosis by integrating a textile-based capacitive pressure sensor array. By considering the sensitivity, durability, recovery/response time, and working range, appropriate sensor cells were chosen. The characterization of the selected pressure sensor cell and its coherence with other cells were examined in the experiments. It is observed that the overall average relative error for the proposed pressure estimation process is 0.18. |
| 4. | Yunculer, Irem Nur; Al-azzawi, Nada; Ayvaz, Ugur; Cetin, Munire Sibel; Ozlem, Kadir; Atalay, Asli Tuncay; Ince, Gokhan; Atalay, Ozgur: A Seamless T-shirt Design with Textile-based ECG Electrodes, Respiration and Posture Monitoring Sensors. In: Proceedings of the 23th World Textile Conference (AUTEX 2024), 2024. (Abstract | BibTeX)@inproceedings{Yunculer2024,Wearable technologies with biosignal monitoring are growing in interest day by day owing to their high degree of flexibility, comfort, reusability, and ability for continuous and long-term monitoring. Adhesive, single-use electrodes are currently the most widespread ECG monitoring method. Nevertheless, they are not ideal for long-term monitoring since the conductive gel dries out over time, adversely affecting signal quality and frequently irritating the skin. Textile-based ECG electrodes are more user-friendly and less prone to skin irritation compared to traditional ECG electrodes since they are dry and non-adhesive. However, the drawback of textile-based electrodes is that they are more susceptible to various conditions, including contact pressure, contact surface area, and electrode location, which can affect the accuracy and dependability of ECG data recorded by e-textiles. This study aimed to improve signal quality and comfort properties while integrating the electrodes and strain sensors with seamless knitting technology. In this study, integrating ECG and posture monitoring into the seamless t-shirt offers an easy-to-use, visually unobtrusive, comfortable, and continuous method for tracking vital health metrics and detecting abnormalities over extended periods. Thanks to the textile-based capacitive strain sensors in the t-shirt, detection of the incorrect posture position that many people have today due to reasons such as having sedentary lives is possible. Capacitive sensors were selected because they have higher linearity than resistive sensors, and their repeatability outperforms the resistive sensor's performan |
| 5. | Pazar, Abdülkadir; Khalilbayli, Fidan; Ozlem, Kadir; Yilmaz, Ayse Feyza; Atalay, Asli Tuncay; Atalay, Ozgur; İnce, Gökhan: Gait Phase Recognition using Textile-based Sensor. In: 2022 7th International Conference on Computer Science and Engineering (UBMK), pp. 1-6, 2022. (Abstract | Links | BibTeX)@inproceedings{pazar2022,Human gait phase detection has become an emerging field of study due to its impact in various clinical studies. In this study, a system is developed to detect the toe-off, mid-swing, heel-strike, and heel-off phases of a gait cycle in real-time by using a textile-based capacitive strain sensor mounted on the kneepad. Five healthy subjects performed walks including those four phases of the gait at a constant speed and gait distance in a laboratory environment while wearing the kneepad. The phases are labeled according to the gyroscope data of the Inertial Measurement Unit (IMU) located on the kneepad. An Long Short-Term Memory (LSTM) based network is utilized to detect the phases using the capacitance data obtained from the strain sensor. Recognition of four phases with 87 % accuracy is accomplished. |
| 6. | Yilmaz, Ayse Feyza; Ozlem, Kadir; Cetin, Munire Sibel; Atalay, Asli; Ince, Gökhan; Atalay, Ozgur: Knitted Interdigital Capacitive Strain Sensor for Wearable Applications. In: W: AUTEX 2022 : 21st World Textile Conference AUTEX 2022, pp. 511-514, Lodz University of Technology Press 2022. (Abstract | Links | BibTeX)@inproceedings{yilmaz2022inter,Wearable electronics is a rapidly growing field that has recently begun to enter the consumer electronics industry with viable commercial devices. To fulfil the increased demand for wearable devices robust, compact, reliable, and cost-effective solutions are required. As a result, it is critical to do extensive research into suitable materials and manufacturing processes. This article describes the creation of a strain sensing textile-based interdigital capacitive sensor that is highly configurable, consumes minimal material, produces no waste, and is reproducible and rapid in mass production utilizing computerized weft knitting technology. In this study, it was shown that the knitted interdigital capacitive sensor structure could match the high working range necessary for wearable electrical and soft robotic applications, thanks to its capacity to stretch up to 100%. This work is expected to advance existing technology in wearable electronics and soft robotics in terms of human body motion sensing. |
| 7. | Paket, Ezgi; Ozlem, Kadir; Elmoughni, Hend; Atalay, Asli; Atalay, Ozgur; Ince, Gökhan: ECG Monitoring System Using Textile Electrodes. In: 2020 28th Signal Processing and Communications Applications Conference (SIU), pp. 1–4, IEEE 2021. (Abstract | Links | BibTeX)@inproceedings{Paket2020,CardioVascular Diseases (CVDs) have a significant share over all medical problems. From this point of view, many studies have been conducted on heart diseases and different heartbeat monitoring systems have been developed. Although Electro-CardioGraphy (ECG) is the most widely used technique among other monitoring systems, ECG measurement with conventional electrodes have also many disadvantages that can be overcome if replaced with textile electrodes. This study involves creation of textile based ECG electrodes, related circuitry designs, signal processing, implementations of peak detection and heart rate calculation algorithms and finally, a real time ECG monitoring application. Moreover, Beat Per Minute (BPM) calculation and comparison of these values with existing ECG devices have been investigated. |
| 8. | Aslan, Ayşe Feyza; Ozlem, Kadir; Elmoughni, Hend; Capello, Leonardo; Atalay, Asli; Ince, Gökhan; Atalay, Ozgur: A Textile-based, Sensorized Pneumatic Actuator for Soft-robotics Applications. In: Proceedings of the 20th World Textile Conference (AUTEX 2020), 2021. (BibTeX)@inproceedings{Aslan2020, |
| 9. | Sevinc, Hasbi; Ayvaz, Ugur; Ozlem, Kadir; Elmoughni, Hend; Atalay, Asli; Atalay, Ozgur; Ince, Gökhan: Step Length Estimation Using Sensor Fusion. In: 2020 IEEE International Conference on Flexible and Printable Sensors and Systems (FLEPS), pp. 1–4, IEEE 2020. (Abstract | Links | BibTeX)@inproceedings{Sevinc2020,One of the main challenges of navigation systems is the inability of orientation and insufficient localization accuracy in indoor spaces. There are situations where navigation is required to function indoors with high accuracy. One such example is the task of safely guiding visually impaired people from one place to another indoors. In this study, to increase localization performance indoors, a novel method was proposed that estimates the step length of the visually impaired person using machine learning models. Thereby, once the initial position of the person is known, it is possible to predict their new position by measuring the length of their steps. The step length estimation system was trained using the data from three separate devices; capacitive bend sensors, a smart phone, and WeWALK, a smartcane developed to assist visually impaired people. Out of the various machine learning models used, the best result obtained using the K Nearest Neighbor model, with a score of 0.945 R^2. These results support that indoor navigation will be possible through step length estimation. |
| 10. | Ozlem, Kadir; Kuyucu, Meral Korkmaz; Bahtiyar, Şerif; Ince, Gökhan: Security and Privacy Issues for E-textile Applications. In: 4th International Conference on Computer Science and Engineering UBMK'19, 2019. (Abstract | Links | BibTeX)@inproceedings{Ozlem2019,In the last decade, there have been numerous challenges in the field of security and privacy since electronic textiles have grown dramatically. Electronic textile applications are becoming the target of attackers due to critical personal data collected the body their sensors. System designers must be aware of the security requirements to develop a well defended application. In e-textile applications, the issue of security is as important as privacy and the designer has to have a broad knowledge. However, studies on security and privacy are highly distributed. In this paper, the distributed security and privacy challenges are collected under a single umbrella for e-textile applications, while making it easier to enter this area for those who start new work in this field made it easier to enter this area. |
| 11. | Kuyucu, Cemal Fatih; Ayvaz, Uğur; Özlem, Kadir; Atalay, Aslı; Atalay, Özgür; İnce, Gökhan: Comparative Assessment of Knee Motion Monitoring Technologies. In: 2019 4th International Conference on Computer Science and Engineering (UBMK), pp. 155-160, 2019. (Abstract | Links | BibTeX)@inproceedings{8907033,Realizing 3D human models digitally is a difficult, yet continually required task. Numerous technologies are utilized to create these models. Due to the variety of technologies used, an evaluation and benchmarking is necessary. This is a comparative study of four such technologies. We compare a wearable textile sensor based motion capture system we designed and implemented to an RGB camera based, depth sensor based, and an inertial measurement unit based motion capture system. The four motion capture systems have been evaluated based on measures such as reliability, ease of use, universality, cost, sensitivity to atmospheric conditions, and flexibility. The preliminary preparations and test conditions for the realization of this comparative study are explained in this paper. Finally, the results of experimentation on one joint have been presented. |
| 12. | Ozlem, Kadir; Atalay, Ozgur; Atalay, Asli; Ince, Gökhan: Textile Based Sensing System for Lower Limb Motion Monitoring. In: Masia, Lorenzo; Micera, Silvestro; Akay, Metin; Pons, José L. (Ed.): Converging Clinical and Engineering Research on Neurorehabilitation III, pp. 395–399, Springer International Publishing, Cham, 2019. (Abstract | Links | BibTeX)@inproceedings{Ozlem2018,In recent years, as a result of multidisciplinary studies in textile science and technology, sensor characteristics are added to the textile products. Thanks to the many features of e-textile products, motion monitoring can be done in novel ways. The prototype developed in this paper, is low-cost, low-power, easy-to-integrate, and fully capable of communicating with mobile devices in a wireless manner. The proposed sensor system can be used to monitor the healing process of patients with neurological injuries. |
Patents
| 1. | Ozlem, Kadir; Gumus, Cagatay; Atalay, Asli Tuncay; Ince, Gökhan; Atalay, Ozgur: Thermally Driven 3D Seamless Textile Actuators for Soft Robotic Applications. 2024, (TR:TR2024/020220: Pending/Applied). (BibTeX)@patent{kadir_patent, |
| 2. | Ince, Gokhan; Cetin, Munire Sibel; Ozlem, Kadir; Khamis, Ibrahim Adel; Yilmaz, Ayse Feyza; Atalay, Ozgur; Atalay, Asli Tuncay: A Textile-Based Stretchable Comb Sensor and Manufacturing Method. 2023, (PCT:WO2025080237A1: Pending/Applied, TR:TR2023/012895: Grant). (Abstract | Links | BibTeX)@patent{gokhan_patent,The invention relates to a textile-based stretchable comb sensor comprising a plurality of hybrid yams (12) and a plurality of dielectric elastomeric yarns (14) in an intersia knitting structure (18), wherein a capacitive sensor structure (14) consisting of conductive electrodes is formed by knitting these plurality of yarns in a combed structure, and a manufacturing method thereof. |
| 3. | Gumus, Cagatay; Ozlem, Kadir; Khalilbayli, Fidan; Erzurumluoglu, Omur Fatmanur; Onal, Erhan; Ince, Gokhan; Atalay, Ozgur; Atalay, Asli Tuncay: Textile-based Large-area Pressure Sensing Arrays. 2023, (PCT: WO2023177380A1: Pending/Applied, TR:TR2022/004079: Grant). (Abstract | Links | BibTeX)@patent{cagatay_patent,The invention is related to a textile-based large-area pressure sensing arrays with a pressure sensor feature comprising a pressure plate (1), a conductive knitted fabric (2), a dielectric thermoplastic polyurethane layer (3), and a double-sided fusible layer (4) for use in smart textile, security, healthcare, entertainment, art industries, and robotic applications, and a scalable manufacturing method of the capacitive based pressure sensor arrays for mass production. |
| 4. | Arslan, Ayse Feyza; Ozlem, Kadir; Khalilbayli, Fidan; Elmoughni, Hend; Ince, Gokhan; Atalay, Ozgur; Atalay, Asli Tuncay: Actuators for Soft Robotic Applications. 2022, (WO2022231556A1: Pending/Applied, EP4330571A1: Pending/Applied, TR2021/007340: Grant). (Abstract | Links | BibTeX)@patent{feyza_patent,The invention is related to soft actuators controlled by fluid pressure. The actuators developed with the invention comprise two sacs which provide for the flexion of a structure upon pressurizing this structure that has an anisotropic flexibility, which is provided by different knitted layers. The knitted layers are produced as integrated with each other by means of the three-dimensional whole-garment knitting technique. The actuators according to the invention can be adapted according to the different requirements and produced with standard qualities. |
Thesis
| 1. | Özlem, Kadir: Fog Computing Architecture for E-Textile Applications. Istanbul Technical University, 2024, (PhD Theses, Advisor: Assoc. Prof. Dr. Gökhan İNCE, Co-advisor: Assoc. Prof. Dr. Ozgur ATALAY). (Abstract | Links | BibTeX)@phdthesis{Ozlem2024Thesis,Textile products are present in almost every aspect of human life. With the introduction of electronic textiles, textile products have become capable of converting various physiological and environmental stimuli into electrical signals, many of which are of vital importance to humans. Therefore, these products require real-time (low-latency) and robust computing systems. However, due to comfort considerations, they cannot accommodate powerful computing resources. In this thesis study, a novel Fog computing-based framework for Electronic Textiles (FogETex) is proposed to meet the needs of e-textile applications. FogETex is a Platform-as-a-Service (PaaS) model that is cross-platform supported, scalable, and operates in real-time. This framework encompasses end-to-end integration of the system including Textile-based Internet of Things (T-IoT) devices, fog devices, and the cloud. The FogETex framework consists of a three-layer architecture: the edge layer, the fog layer, and the cloud layer. The edge layer includes T-IoT devices that collect data from e-textile sensors and transmit it to the gateway device. Gateways are typically mobile phones that users carry in their daily lives. These devices are responsible for forwarding the collected data to the fog layer and visualizing the processed data. If the T-IoT device is equipped with its own Wi-Fi or LTE module, it can directly transmit data to the fog layer without requiring a gateway device. The second layer includes broker and worker devices. The worker device is responsible for handling incoming computational requests, while the broker device manages the fog node. The broker monitors resource utilization data sent in real time by the worker devices at regular intervals to determine if any devices are overloaded. Based on resource usage, the broker assigns the most suitable worker device when a new user connects to the fog node. For security reasons, only the broker device within the fog node has a connection to devices on the Wide Area Network (WAN). As a result, in outdoor applications, data is transferred to the worker devices via the broker. In this setup, the broker acts as a proxy between the worker devices and the users. The third and top layer is the cloud. The cloud device assigns users to an appropriate fog node based on availability information provided by the broker. While the cloud determines the suitable fog node, it does not interfere with the worker assignments within the fog node itself. This structure ensures decentralized management. Even if one node fails, the others can continue performing their tasks independently. Additionally, the cloud and broker devices, besides managing their primary responsibilities, are also capable of providing computational services. Therefore, during system overloads, these devices can step in to serve users, ensuring continued functionality. Since e-textile sensors generate time-series data and many sensors collect tens of data points per second, communication between the gateway device and the worker device is established using a WebSocket structure. This approach eliminates the need to repeatedly establish connections for every data transmission, enabling asynchronous and bidirectional data flow. On the other hand, operations such as device allocation requests made by the user to the cloud or broker are one-time processes and are managed via a RESTful API developed specifically for this purpose. Additionally, each device is equipped with a user interface that allows system administrators to monitor the status of the devices. This data can be utilized to make decisions about provisioning additional devices for overloaded fog nodes, ensuring optimal system performance. To bring this thesis to fruition and understand the nature of the e-textile applications, a variety of applications were developed using electronic textiles in areas such as gait phase detection and hand motion recognition. On the other hand, to ensure that the developed framework functions as a comprehensive end-to-end system rather than a data processing platform, research was also conducted in textile-based soft robotics, another domain of smart textiles. These efforts include exoskeleton gloves for individuals with muscle weakness. Selected case scenarios from these applications were used to test the FogETex system. For the first application of the proposed framework, a deep learning-based gait phase analysis application using textile-based capacitive sensors is employed. In this case study, knee movements were captured using a textile-based capacitive sensor placed on the test subject's knee. The sensor data was converted into gait phases using a deep learning-based machine learning method. In the next stage, these gait phase data are intended to be used as control signals for the artificial muscle actuator developed for foot drop treatment. FogETex was evaluated in terms of time characteristics, resource usage, and network bandwidth usage using a mock client to determine the ideal system performance and an actual client to conduct real-world tests. All these tests were repeated on worker, broker, and cloud devices to validate indoor applications. Additionally, for outdoor applications, tests were conducted by connecting worker and cloud devices through WAN. The broker device acted as a proxy between the worker device and the user in this test. The fog devices outperformed the cloud system in these metrics. In this case scenario, the performance of the FogETex framework was analyzed across different devices in applications with a single sensor. Additionally, a stress test was conducted to evaluate the framework's capability to handle multiple users. It was found that worker devices could serve up to 6 users, broker devices up to 18, and the cloud up to 14 users. The system demonstrated superior performance when three or more worker devices were employed compared to other configurations. Considering rental and device costs, the worker devices were deemed more cost-effective in terms of performance. Lastly, the FogETex framework was compared with other systems in the literature that could serve as competitors and are widely used in various studies. The comparison revealed that FogETex outperformed its counterparts in metrics such as latency, execution time, response time, and operational frequency. To demonstrate the versatile applicability of the proposed FogETex framework further, a cloud-based remote manipulation system was developed, integrating e-textiles and textile-based soft robotic systems. The objective of this research is to combine a textile-based sensorized glove with an air-driven soft robotic glove, operated wirelessly using the developed control system architecture. The sensing glove equipped with capacitive sensors on each finger captures the movements of the medical staff’s hand. Meanwhile, the pneumatic rehabilitation glove designed to aid patients affected by impaired hand function due to stroke, brain injury, or spinal cord injury replicates the movements of the medical personnel. The proposed artificial intelligence-based system detects finger gestures and actuates the pneumatic system, responding within an average response time of 48.4 ms. The evaluation of the system further in terms of accuracy and transmission quality metrics verifies the feasibility of the proposed system integrating textile gloves into IoT infrastructure, enabling remote motion sensing and actuation. In addition, the system was tested using various concurrency and inter-process communication methods. The system was also tested with multiple worker devices. It was observed that the system could serve up to 10 devices with 1 worker, up to 22 devices with 2 workers, up to 26 devices with 3 workers, and up to 23 devices with the cloud system. On the other hand, this research also tested the FogETex system in multi-sensor e-textile applications. Models developed using various machine learning methods were introduced to the system as different applications, demonstrating that the framework can run multiple applications simultaneously. Although the framework was designed as a fog computing architecture, it can also operate exclusively as a cloud or edge computing system. In this study, it was confirmed that the framework can function effectively even without fog devices. Furthermore, the developed system successfully integrated e-textiles and soft robotics, proving its capability to operate as a complete end-to-end solution. The results from both applications demonstrated that the FogETex framework operates in real-time and with robust performance. While the primary goal of the FogETex system is to be utilized in e-textile applications, it can also process signals generated by e-textiles to control textile-based soft robotic structures. Thus, it serves as a framework that encompasses both e-textiles and soft robotics domains. Besides being developed primarily for electronic textile applications, FogETex framework can accommodate other IoT devices as well. |
| 2. | Özlem, Kadir: Textile Based Sensing System For Leg Motion Monitoring. Istanbul Technical University, Graduate School Of Science Engineering and Technology, 2018, (Masters Theses, Advisor: Asst. Prof. Dr. Gökhan İNCE). (Abstract | Links | BibTeX)@mastersthesis{Ozlem2018Thesis,In recent years, electronic products have become integrated with textile products with the production of chips having small size, being cheap and needing low energy need. Thanks to research in the field of textile, e-textile was born from the electrical response of textile product to the physical environments. With the multidisciplinary studies carried out in the fields of electronics, computers, control, and textiles, these electronic textiles are now being transformed into products used by consumers. It is possible to see electronic textiles in different fields such as sports training, robotics, health imaging, body motion analysis, etc. The textile based sensors have four different types: resistive, capacitive, optical and solar. Capacitive and resistive sensors can be used in motion capture systems. Resistive sensors have disadvantages such as low linearity, drift problem and high response time, whereas capacitive sensors have good features such as high linearity, low response time and high resolution. Although capacitive sensors have many advantages, noise is generated in the measurement due to the distance between the sensor and the measuring device. Motion capture systems, rely on three different techniques: optical, magnetic and mechanical. Optical motion detection systems operate according to the principle of extracting the skeletal structure of humans by using image processing methods. However, this system has many disadvantages such as the ability to measure in a specific area and require high processing cost in the calculation units. Magnetic motion capture systems are based on the principle of finding joint angles by magnetic sensors placed on the body. Unlike optical motion capture systems, these systems do not require a specific area of operation and high processing cost. However, these systems are affected by objects such as metals and circuits that will create an electromagnetic effect since these systems use magnetic sensors. In mechanical systems, joint angles are determined by sensors placed on the joints. These systems are not affected by the magnetic field and are not required to be used in a specific area. Since the sensor data is equal to the joint data, there is no calculation load. However, special clothing equipped with sensors should be used in such motion capture systems. The cost of this special clothing is the biggest drawback of such motion capture systems. This thesis deals with increasing the measurement quality by reducing the noise due to distance in the measurement of textile based capacitive sensors, creating a prototype with integration to textiles, and developing a motion monitoring system that will receive and store data from the prototype. This thesis focuses on the problem of noise in the measurement results due to the distance which is the biggest problem of capacitive sensors. This makes it possible to make use of the advantage of the capacitive sensors. The electrical system consists of textile based capacitive sensors, microcontrollers, bus, a transmitter, a mobile phone, and a battery. Microcontrollers are placed closest to the sensor. Thus, the noise caused by the distance is minimized. The microcontrollers are connected to the transmitter via bus. The transmitter transmits both requests and power to microcontrollers via the bus. The microcontroller measures and transmits them to the transmitter via the same line. Since the I2C connection is used in the system, the four-wire bus is created for the power and data line. The transmitter transmits the received data to the mobile phone via a Bluetooth connection. The entire system is fed with the battery connected to the transmitter. An Android application has been developed to receive data over a mobile device. The application shows the data to the user and sends them to the server. The server saves the data to the database and also sends it to other web clients instantly. With the prepared web front end, the measurement results are displayed instantaneously. In addition, historical measurement data is displayed on the web front end. Data communication between the web service, phone and web clients is made by socket programming to be fast and instantaneous. The sensor used in the system is a textile based flexible capacitive sensor. This sensor consists of two conductive fabrics and the dielectric material. The sensor acts as a parallel plate capacitor. The increase in the length of the sensor increases the electrode area of the sensor. This change also increases the capacitance of the sensor. In the textile integration of the design, the sensor is placed on the knee using the knee bracket. The microcontrollers are also located near the sensor and connected to the sensor. The bus to be established between the transmitters and the microcontrollers is made of conductive yarns. These conductive yarns are sewn on the fabric strip. In this way, the prototype will be tested under similar conditions to the commercial product to be prepared in the future. In the experiments with the prototype, the test object walks first, then stops, and finally makes a squatting motion. During walking, all characteristics of phases of gait can be extracted from the measurement data. The theoretical and practical results are similar when compared. At the same time, when the signals from both knees are compared, there is a phase difference between the signals parallel to the walking. In the motionless phase, there is no change in the signals. During the squatting motion, both signals move simultaneously, and there is no phase difference between them. When all stages are examined, it is verified the system successfully performs the lower limb motion capturing. The contribution of thesis is that we minimized the noise generated in the measurement results due to the distance which is the biggest problem of capacitive sensors. In addition, a system was prepared to collect data from users and send end-to-end data. Since the system is designed with low-priced materials, it will be suitable to be commercialized. In following studies, a follow-up system for patients in the health care domain, physiotherapy applications, and sports applications etc. can be developed. This thesis will also contribute to science as it opens new fields of study. |