April 26, 2011

Sheng Jiang, CompEHason Ng, CompE

Sagar Biddanda, EERuoxi Jiang, EE

Assists shoppers Navigation system with the ability to

◦ Locate items◦ Provide detailed directions

Small scale proof of concept Prototype cost: $230

Locate items◦ Acquire user input◦ Query database for item information and location

Provide detailed directions◦ Obtain current cart location◦ Find optimal path from current location to the

item

Distance from Source

(m)

Signal Strength

Free Space (dB)

Signal Strength

Steel Shelf (dB)

2 -55 -71

3.4 -63 -78

4 -66 -80

OS: Ubuntu 10.10 Maverick Meerkat Python programs

◦ XBee control◦ Navigation algorithm◦ Positioning system◦ GUI

TKinter library

Location determined by signal strength of beacons

Mapped to store layout

Shelf

Beacon Coverage

Proposed implementation: A* navigation algorithm◦ Finds least-cost path from a given initial node to

destination node Implemented Dijkstra’s navigation

algorithm◦ More consistent performance and accuracy

Item Name LocationSalt 001001Jasmine Rice 020048Milk 008037

Video output◦ S-Video◦ HDMI to VGA

Initial location detection Touchscreen not recognized by Ubuntu Scaling beacon network to store layout

Item Qty Total CostDVI-D to VGA Converter

1 $50

XBee 802.15.4 RF Modules

6 $120

XBee Adapter 6 $60

Item (Borrowed) Qty Est. CostBeagleBoard-XM 1 $1507-inch LCD Touchscreen

1 $200

•Total Amount Spent: $230•Total Estimated Parts Cost: $580•Total Estimated Cost (Network with 5 nodes, including labor): $600•Total Estimated Cost (1 unit, including labor): $450

Goal Actual Proposed

Location Detection 3±1m 3±1m

Navigation Dijkstra’s Navigation Algorithm

A* Navigation Algorithm

Map Search Time 4±1s 4±2s

Suggested Improvement Benefit

Scalability Adaptable to different store layouts

Multithread application Faster response time

Turn off display when idle Improved power management

Index database Quicker search times

High resolution map display More user friendly

Case and shopping cart mount Protect the BeagleBoard from damage