With Watch+Strap we propose to enrich smartwatches with interactive StrapDisplays in order to extend their input and output capabilities.
Watch+Strap in 4 Minutes
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Quick Access
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Abstract
While smartwatches are widely adopted these days, their input and output space remains fairly limited by their screen size. We present StrapDisplays—interactive watchbands with embedded display and touch technologies—that enhance commodity watches and extend their input and output capabilities. After introducing the physical design space of these StrapDisplays, we explore how to combine a smartwatch and straps in a synergistic Watch+Strap system. Specifically, we propose multiple interface concepts that consider promising content distributions, interaction techniques, usage types, and display roles. For example, the straps can enrich watch apps, display visualizations, provide glanceable feedback, or help avoiding occlusion issues.
Further, we provide a modular research platform incorporating three StrapDisplay prototypes and a flexible web-based software architecture, demonstrating the feasibility of our approach. Early brainstorming sessions with 15 participants informed our design process, while later interviews with six experts supported our concepts and provided valuable feedback for future developments.
Presentation @ ACM CHI ’20
The paper is published in the Proceedings of the 2020 CHI Conference. It was planned to present our Watch+Strap paper at the conference in Honolulu, Hawaii, USA in April 2020, however, the conference had to be canceled. Instead, we are providing a recorded talk on YouTube:
You can also watch our shorter 3 minute presentation from the 2020 Virtual German CHI Week.
Publication
@inproceedings{Klamka2020,
author = {Konstantin Klamka and Tom Horak and Raimund Dachselt},
title = {Watch+Strap: Extending Smartwatches with Interactive StrapDisplays},
booktitle = {Proceedings of the CHI Conference on Human Factors in Computing Systems},
year = {2020},
month = {4},
location = {Honolulu, Hawaii, USA},
pages = {72:1--72:15},
doi = {10.1145/3313831.3376199},
publisher = {ACM}
}List of additional material
,
@inproceedings{klamka2021_epaper,
author = {Konstantin Klamka and Raimund Dachselt},
title = {Bendable Color ePaper Displays for Novel Wearable Applications and Mobile Visualization},
booktitle = {The 34st Annual ACM Symposium on User Interface Software and Technology Adjunct Proceedings},
year = {2021},
month = {10},
isbn = {978-1-4503-8655-5/21/10},
location = {Virtual Event},
doi = {10.1145/3474349.3480213},
url = {https://doi.org/10.1145/3474349.3480213},
publisher = {ACM},
address = {New York, NY, USA},
keywords = {Color, ACeP, EPD, ePaper, E-Ink, electrophoretic, flexible, bendable, StrapDisplay, wearable, personal InfoVis, HCI, toolkit, mobileVis}
}List of additional material
Source Code & Online Documentation
One main contribution of our Watch+Strap paper is its open research platform. For that, we provide all materials in the following. The source code of the Watch+Strap components as well as the used 3D models are made publicly available on Github. Specifically, our project consist of three repositories:
The application server for the Watch+Strap prototype, which is running all application logic. Watch and StrapDisplays connect to this server. github.com/imldresden/WatchStrap-app-server
Simple Tizen application for connecting a Samsung Gear smartwatch to the Watch+Strap application server. github.com/imldresden/WatchStrap-tizen-app
Firmware and 3D-Models for the Arduino-based E-Ink StrapDisplays that connect to the Watch+Strap application server can be found on this project website.
Building Instructions: E-Ink StrapDisplays
Fabrication Steps
1. Preparing the Membrane Potentiometer
Image | Part | Description |
---|---|---|
ThinPot Film Potentiometer l=50mm; TSP-L-0050-103-3%-ST |
We used three ThinPot Film Potentiometer from Spectra Symbol to continuously measure pressure input in three lines. Available, for example, at Mouser, Digi-Key or Reichelt Elektronik. | |
Transparent Film 2mm |
||
Highflex Cable 0.05mm²; PVC 0.8mm; 10×0.08mm |
Available, for example, at Conrad Electronics. | |
Heat Shrink Tubing d=1.20mm; ratio: 2:1 |
||
Machine Male Pin Headers |
2. Adding the E-Ink Display
Image | Part | Description |
---|---|---|
Flexible e-Paper display 2.13inch e-Paper (D); SKU 14986 |
||
e-Paper Adapter | ||
Flex Connector Cable AWM 20624; 24 Pin |
||
Double Faced Adhesive Tape |
3. Finalizing the StrapDisplay
Image | Part | Description |
---|---|---|
Quick Release Spring Bar l=22mm |
Available, for example, at Amazon. | |
Sewing Kit | ||
Velcro Ribbon | ||
Double Faced Adhesive Tape |
3D Model | Description |
---|---|
Strap Housings strap_e_ink_housing.stl strap_e_ink_housing_cover.stl |
First, we glued a piece of velcro on the back of the StrapDisplay housing. To strengthen the connection, we also sewed the velcro since closing and opening the velcro continuously exert forces to the adhesive connection. As a next step the flexible E-Ink display and membrane potentiometers must be slid into the housing.
In order to cover and protect the breakout of the strap electronics, we designed a cover that could be seamlessly slide above the strap without the need of any glue. However, please take care that you did not damage any cables or connectors.
4. Building an Analog-Digital-Converter Shield
Image | Part | Description |
---|---|---|
e-Paper ESP8266 Driver Board |
||
16Bit ADC ADS1115; 4 Channel AD; SKU:18443 |
||
10k resistor | ||
Prototyping PCB Phenolic paper 0.1″/2.54mm, 80mm x 52mm, 35µm |
We used these prototyping boards as a basis for our circuits. Available, for example, at Conrad Electronics. | |
Small Female Pin Headers | ||
Male Pin Headers | ||
Jumper wire YV; white; cross section: 0.2mm² ; outer:1.1mm |
5. Creating a Housing for the Electronics
Image | Part | Description |
---|---|---|
Sewing Kit | ||
Velcro Ribbon | ||
Elastic Ribbon |
3D Model | Description |
---|---|
Electronics Housing controller_housing_base.stl controller_housing_cable_config.stl controller_housing_cable_fixation.stl controller_housing_cover.stl |
6. Program the Microcontroller
The Arduino source code for the E-Ink prototype can be downloaded here:
strapdisplay-e-ink-prototype.zip
*Please note that we slightly modified the Adafruit_ADS1015 library for our prototype. The customized version is part of the zip download package.
7. Final Assembly
Related Student Theses
Novel Approaches for Visualizing and Interacting with Data on Smartwatches
Anselm Bunsen June 7th, 2019 until August 23rd, 2019
Supervision: Tom Horak, Konstantin Klamka, Raimund Dachselt