ECSkin: Tessellating Electrochromic Films for Reconfigurable On-skin Displays
[video coming soon]
Emerging electrochromic (EC) materials have advanced the frontier of thin-film, low-power, and non-emissive display technologies. While suitable for wearable or textile-based applications, current EC display systems are manufactured in fixed, pre-designed patterns that hinder the potential of reconfigurable display technologies desired by on-skin interactions. To realize the customizable and scalable EC display for skin wear, this paper introduces ECSkin, a construction toolkit composed of modular EC films. Our approach enables reconfigurable designs that display customized patterns by arranging combinations of premade EC modules. An ECSkin device can pixelate patterns and expand the display area through tessellating congruent modules. We present the fabrication of flexible EC display modules with accessible materials and tools. We performed technical evaluations to characterize the electrochromic performance and conducted user evaluations to verify the toolkit's usability and feasibility. Two example applications demonstrate the adaptiveness of the modular display on different body locations and user scenarios.
Publication:
ECSkin: Tessellating Electrochromic Films for Customizable On-skin Displays
Pin-Sung Ku, Shuwen Jiang, Wei-Hsin Wang, Cindy Hsin-Liu Kao
Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies (IMWUT) 2024
Project Credits:
Hybrid Body Lab at Cornell University, directed by Cindy Hsin-Liu Kao
Research Team:
Pin-Sung Ku (Lead Researcher), Shuwen Jiang, Wei-Hsin Wang, Cindy Hsin-Liu Kao (Lab Director)
This project is funded by the National Science Foundation under Grant IIS-2047249
We present ECSkin, a construction toolkit for fabricating on-skin electrochromic displays.
ECSkin Tessellation Designs of Electrochromic Modules
We devised a free-form surface display by connecting several electrochromic modules, such that the display area on each module seamlessly aligns with the others, forming customizable 2D display patterns.
The Three-layer Structure of an ECSkin Module and the Two Control Mechanisms
The top layer is the electrolyte gel; The middle layer is co-planed by the electrochromic ink and counter electrode; The bottom layer is a skin-friendly and conforming silicone-based substrate.
We implemented two ECSkin display control schemes. (1) An addressable EC module with a digital switch can be controlled using the 1-wire protocol. (2) A manual EC module can be activated only when the magnetic module control switch is attached to the counter electrode.
The Fabrication Process of an ECSkin Module
(a) Screenprint the electrochromic and counter electrode inks. (b) Printed ink layers on white vinyl stickers. (c) Remove sticker backings and adhere to ink layers on the silicone-based substrate. (d) Transfer conductive fabric traces to the substrate. (e) Paint silver chloride ink between the EC ink and traces. (f ) Cut and apply electrolyte gel to cover the EC ink and counter electrode. (g) Install magnets to the back of the substrate. (h) Attach vinyl film for insulation backing.
ECSkin Workshop Study
The study aims to understand how and what novice users could learn and design the modular EC displays with the toolkit.
ECSkin Applications
Workout Posture Monitor made with a three-segment ECSkin display. (a) Square modules are connected in a round band on the thigh. (b) The arc-shaped modules are tessellated into a knee pad. (c) The curved display on the calf is made of diamond-shaped modules.
Reconfigurable Timer designed with manual arc-shaped ECSkin modules. (d) An untethered device made with an MCU and a battery. (a) Wrist timer for bicycling. (b) Heel timer to prevent injury wearing high heels for long. (c) Belly timer for changing sanitary pads. (d) Neck timer as a gentle alarm. (e) Inner forearm timer as a hydration reminder.
