As per the description blurb the peripheral is:
An upper arm screen designed to provide an alternate means of receiving mobile notifications. It can connect to a phone or another bluetooth device, display text based messages and provide notifications via strips of light on it’s shell. The intention is to explore a less commonly used part of the body for displaying various information.
The project went through three major iteration steps. It was initially intended as a hand mounted device, and that prototype can be seen in the first image below. After suggestions from the rest of the class I tested it on the upper arm and that position became much more comfortable for its larger size. This second iteration included an all black triangular design with thin transparent vellum edges. While the third added a prominent RGB LED indicator and provided a more transparent shell.
- Fio v3 – ATmega32U4
- Serial Miniature OLED Module – 1.5″ (μOLED-128-G2-GFX)
- RN42-XV Bluetooth Module – PCB Antenna
- Polymer Lithium Ion Battery – 2000mAh
- LED – RGB 5mm Square (Piranha)
- Prototyping components (boards, connectors, wire, fabric etc)
During these prototyping stages two major challenges drove the time spent on this project through the roof: debugging the circuitry and communicating over Bluetooth.
Due to the way the OLED behaves the step up and the breakout I created for it required extensive testing. Although the screen might be powered on it might not display anything due to issues with the reset pin or RX and TX pins. Further circuit debugging came from being unsure of the way the OLED communicates (or doesn’t) over a serial connection. A post will be coming up with greater detail on this, as I am still trying to figure out a way to establish a functional connection.
The issues with Bluetooth were mostly due to varied hardware and lack of spec detail. On Windows the mobile module required an authentication token, while on the MAC it actually wouldn’t connect if one was provided explicitly. Luckily with the help of a cross platform serial terminal application (CoolTerm) the module was programmed and tested throughout development. (Also big thanks to arkadiraf on the Arduino Forum and many users on the arduino IRC channel for answers to my endless questions. )
The Process Gallery
Hover for captions:
The major change in the third iteration is the addition of a notification RGB Led, which changes its state based on this simpe sketch. Serial1 on the FIO communicates directly to the Bluetooth chip attached to it and all I had to do (once the over complicated setup was complete) is read characters from it sent by the phone.
On the screen itself I designed an interface demo that shows what the application would do if the screen were to display data from the phone. Three rectangles represent the type of notice that the phone would send, and three colors represent the time from the notice. Notices could be text messages, emails, messages from various applications or missed calls. Originally I planned to scroll or shift through strings of text, but quickly realized that the position and size of the screen better accommodated a more abstract representation of the notifications. The categorization of what each size meant would be left to the user, though the base concept relates their size to the level importance of the notification.
Final Components and Assembly
Overall I am really happy with the final outcome. It was a challenging but exciting process of using these new to me technologies in a wearable form. Although it is not without its issues I really like the idea of Bluetooth like communication, as a variety of devices can connect to a single object and speak to it using very basic and easily defined commands. Constructing this piece was also a fun process, playing around with the mounting on the RGB LED was especially neat. Perhaps one of the most exciting (and oddly least technological) parts was playing with the shadows created by the wiring and LEDs on the vellum surfaces.
I am now really excited for my next year as the thesis subject I will focus on involves a set of wearable tech pieces which continue exploring many of the discoveries found through this project. I will also continue to interface with the OLED screen and provide a comprehensive tutorial on my findings about it. I think that the technology and quality provided by this OLED device is very useful in the wearable context and hope to fill the major gap in documentation for this particular area of application.
This project also led to the most rewarding experience this semester of demoing this at the yearly Technosapien show here in Toronto. I am really honored to have been given the chance to attend and see so many other wearable tech projects.
Huge thanks to Kate Hartman for organizing this event and giving invaluable advice, as well as Katie Ballinger and Rickee Charbonneau for their help and support throughout the project.
The Show and Final Product