Team 5 Good Vibrations 18549 Embedded Systems Design

Team 5: Good Vibrations 18549: Embedded Systems Design Bryce Aisaka Justin Beaver Tony Felice Skanda Mohan

Team Members Bryce Aisaka Justin Beaver Tony Felice Skanda Mohan baisaka@andrew. cmu. edu justinbeaver 8@gmail. com romman 0012003@gmail. com skandam@andrew. cmu. edu http: //www. ece. cmu. edu/~ece 549/spring 10/team 5/index. html

Concept • A silent, portable, comfortable, batteryoperated, phone activated, vibrating pillow cover • User sets time to wake up via phone UI, pillow vibrates at that time to wake user • Competitive Advantages: – Portability: Just need to carry your cell phone and our pillow cover – Customizable: Can use our pillow cover with the pillow of your choice

Goals • Silent: Should not wake up anyone else • Portable • Battery Operated: Does not need to be plugged in during usage • Phone activated: Can use the cell phone that you already own to activate the pillow vibration • Customizable • Fail-Safe: Sound is emitted only if person does not wake up after set time limit • Effective: Needs to be able to wake someone up

Architecture Serial port Bluetooth module Arduino Nano Bluetooth enabled Android phone Solarbotics VPM 2 Vibrating Disk Motor 3 x Triple A’s

Components Solarbotics VPM 2 Vibrating Disk Motor Padding +Covers Arduino Nano +Bluetooth module (Blue. Smirf Gold) Battery Holder +AAAs Bluetooth Enabled Smart-Phone (Motorola Droid) User Interface

Experimentation Campaign • Bluetooth Range – Method: Stand at a certain distance and measure the time it takes for the BT connection to be established and a byte to travel round trip – Took 30 measurements at increments of 5 feet to ensure reproducible results • Idle Power Consumption – Method: Leave all components of the system running in idle state, measure how long it takes for batteries to run out • Continuous Power Consumption – Method: Leave the vibration motors continuously running, measure how long it takes for batteries to run out.

Experimentation Campaign (cont. ’d) • User Survey – Method: Ask 10 test users to use our product and answer a series of questions – Questions address comfort of pillow, willingness to adopt our product, and pricing of a mass-produced version of our product

Experimental Results • Bluetooth range test results • Idle Power Consumption: ~24 hours • Continuous Power Consumption: >65 minutes

Experimental Results (cont. ’d) • Number of users who said… – – – The pillow was comfortable while handling it: 9/10 The pillow was comfortable while lying on it: 10/10 They would wake up from the high vibration setting: 9/10 They would wake up from the medium vibration setting: 8/10 They would wake up from the low vibration setting: 2/10 They would prefer our product to how they currently wake up: 6/10 • Of the people who said they prefer our product, the number of users who said… – They would be willing to charge the pillow as often as they charge their cell phone: 4/6 – They would be willing to pay up to $20 for our product: 6/6 – They would be willing to pay up to $30 for our product: 2/6 – They would be willing to pay more than $30 for our product: 1/6

Insights from Measurements • Battery life is sufficient, but daily recharging may be required • Bluetooth range is long enough for typical bedroom use • Our comfort and effectiveness requirements seem to have been met • Users seem reluctant to break habits and switch to a newer, novel way to wake up • The target price is $20

Open Issues • Longer battery life • A 5 V power solution for more powerful vibration • Sensors on pillow cover • Making the pillow cover washable

Conclusions • Some things we learned: – Arduino has much more computing power than we actually need, but is really convenient – Bluetooth is surprisingly easy to use, once you find the proper UUID • What we accomplished: – Building a finished product • What we would do differently: – Order parts earlier