Team 2iDOCENT: Phase 2

Kirk GuotanaManagement

guotanak@msu.edu

Vadim KimDocument

kimvadim@msu.edu

Adam PartloWebmaster

partload@msu.edu

Shreyas ThiagarajasubramanianPresentation

thiagar3@msu.edu

Introduction

• iDOCENT – (indoor Digital Orientation Communication and

Navigation Technology)

• A system to solve the problem of indoor guided navigation

• Targets visually impaired users– Working with MSU RCPD– Sponsored by Marathon

Background

• iDOCENT Phase 1 – Used Wi-Fi triangulation

• Phase 2 implements– Audio signal– Microphone modules

• Advantages of Phase 2– Smartphone connection to internet– Not dependent on Wi-Fi

Objectives

• Ten foot accuracy

• User friendly

• Audio feedback

• Minimal infrastructure

System Setup

System Protocol

1. The smartphone contacts the server.

2. Server sends online confirmation.

3. Smartphone emits audio signal.

4. Receiving mics relay a message to the server.

5. Server analyzes the data, sends the user his position.

How does it calculate position?• The server uses the first two timestamps for calculations.

– If two are not given, only one is considered.

– Position of microphones is known

– Using difference in timestamps and the speed of sound, position of the user relative to each mic can be calculated.

System Design

• Minimizes transmission delay– No timestamp is collected from the cellphone– Microphones are connected through Ethernet

• Timestamps will be on server side– Ensures clock synchronization

• Process repeats to guide the user accurately

System Components

• Smartphone platform:– Samsung Focus– Windows Phone 7, C#– Easy to program

• Server– Asp.NET (C#)– Online webhosting

System Components

• Microcontroller – NetduinoPlus– Ethernet enabled– Digital I/O features– DSP capabilities– Very easy to program (C#)

Things to consider

• Frequency Interference• Hearing Ranges (Infants/Animals)• Multiple Users• Server Crash• Lack of Signal• Range

BudgetItem Quantity Unit Cost Price

Samsung Focus 1 0.00 0.00NetduinoPlus 4 59.95 239.80Electret Microphones 4 4.95 19.80WinHost Web Hosting 2 months 4.95/mo 9.90

Total $269.50

Questions?