Bluetooth TwiddlerUbiquitous Computing

CS 7470

Jeremy Rogers

Amirali Charania

Background

Current Twiddler's Drawbacks PS/2 High energy consumption Loses custom configuration

Background

Current Twiddler's Drawbacks PS/2 High energy consumption Loses custom configuration

Our Twiddler's Advantages HID device via Bluetooth Lower energy consumption Rechargable

Motivation

Related Work

Wireless Twiddler Used with QBIC belt computer No specific plans or code

Bluetooth Accelerometer-based Twiddler Developed by a GT grad in 2004 Uses Serial Port Profile, not HID Profile “Rough Guide” – no code / documentation Rechargeable Li-Ion battery Fits inside Twiddler case

Related Work (Continued)

Current Design

HID Profile

What We Did - Hardware

The "Hacked" Bluetooth Accelerometer

Components:

-keygrid-battery leads-connector-power plug (NS)

On/Off Switch Closeup

What We Did - Software

Bluetooth Protocol Stack

Bluetooth Profiles

Development Environment

Bluetooth chip – Bluecore2 Ext Bluelab xIDE Casira Development Kit

Application Stages

Library Initialization Connection Library HID Library

HID Connection Detection of Keypress Reporting of Keypress

Improvements

Reporting Method Robust Pairing (Linux and Mac) Hardware

External storage of keychord mappings Line configuration

Strobing Method Mouse and Accelerometer LED Indicators

Acknowledgments

Thad Starner

Peter Presti

Jay Summet

Kent Lyons

Daniel Ashbrook

Girish Saini

Travis Deyle

Adit Ranadive