Yong Ki Son

Nonintrusive measurement of heart rate using a flexible sensor array

Wide interest in wearable technology has brought progresses in wrist-worn, nonintrusive bio-signal measurement techniques. However, previous wrist-worn devices have rigid form-factors, causing them to be vulnerable to motion artifacts. In this paper, we propose a wrist-worn, nonintrusive heart rate sensing module which has an array of sensors mounted on a flexible band. Its flexibility allows it to fit users with various wrist diameters and improves robustness to motion artifacts. We adopted wire bonding techniques which allowed the resulting module to be small and thin like a wrist watch.

Interfacing Mobile Devices with Electronic Textiles Using Spatial Information

Study results on commercial electronic textiles (e-textiles) have shown that convenience aspect needs to be improved. In this paper, we propose an enhanced version of Drop-n-Play interface that provides an easy and hazard-free method to connect mobile devices to e-textiles. User tests have been conducted to demonstrate its performance.

Wearable network using Optical e-Textile Antenna for NLOS

This paper proposes an Optical e-Textile Antenna (OTA) that overcomes line of sight (LOS) limitation of IrDA-based wearable network. Because the OTA can create a routing path for the optical signal among communication devices, that allows information exchange under the NLOS (non LOS) environment between receiver and transmitter. The proposed OTA is a piece of cloth made of e-Textile, it can be easily adapted to wearable network. The OTA either absorbs the optical signal in free-space at its maximum, close to its front-side, or emits the optical signal evenly. This paper verifies the performance of bi-directional communication of the proposed OTA with the prototype system.

EntWear: A durable smart jacket to control media devices

In this paper, we developed a smart jacket using a drop & play interface to control media devices by using a touchpad embedded in the jacket. The inner circuit of the system is made by using transfer printing circuit technique to increase the durability of the system.

A flexible textile wristwatch using Transfer Printed Textile Circuit technique

In this paper, we propose a process on forming durable and flexible circuits directly on textile using transfer printing technology. This process allows electronic textiles to demonstrate stable performance in the presence of physical stress, and allows us to implement high resolution textile circuits, compatible with variety of commercially-off-the-shelf chips. Using our technology, a flexible, wearable, and durable textile wristwatch is developed.