Concept
Motivation
Competition
Tech Specs
Requirements
Architecture
Use Cases
System States
Risks
Error Handling
Implementation
Test Cases
Evaluation
Lessons
Fun Stuff
References
18-549 Home

TEAM 1: BabyHunters
Spring 2009

MEMBERS

Bill Liao
Yu Wang
Richard Wang

PROJECT CONCEPT

The aim of this project is to set parent's minds at ease regarding the whereabouts of their children by use of an inconspicuous device worn on the child and a monitoring device to pinpoint the location of their child in cases of emergency. We will use a combination of embedded components including GPS devices, monitor screens, and CPUs.

MOTIVATION

Currently, parents must use arcane methods, such as tying their kids onto a rope, to ensure that they know where there children are. Our device will help to set the minds of parents at ease without physical annoyances to both the parent and the child.

COMPETITIVE ANALYSIS

GPS Sneakers
Daniel's sneakers look like most others on the market , except they have on-off buttons hidden near the shoelaces and a GPS chip in the soul of the shoe. The wearer can activate the system by pressing the button, or in case of an emergency, the monitoring service can activate the system remotely and locate the person. The adult version of the shoes, ideal for Alzheimer's patients. Cost about $350 and the monitoring service is an additional $19.95 per month. Our product differs in that it will be cheaper, more mobile, and tracking can be done by the parent.
P-Trac Pro GPS device
The P-Trac Pro is a small, sturdy, portable tracking device, at about 3 inches long it's about the size of a pager. With an internal antenna and rechargeable battery it requires no external connections, making it easy to conceal within a child's jacket or stroller. It operates on the CDMA wireless network, providing nationwide coverage. Tracking is done through a website interface. Cost about $1000. Our product differs in that we will allow tracking through a mobile device and much cheaper.

TECHNICAL SPECIFICATIONS

Hardware:

GM862 Evaluation Kit - USB

Direct Link
Nokia N95 Cellular Phone
2 SIM Cards

Software:

in-house customized software

Protocols:

GSM
GPRS
SMS

REQUIREMENTS

Fuctional:

Relay information to the receiver on a timely basis to be able to track the movement of the gps.
Monitor and minimize the power consumption of the gps to make the duration worthwhile.
To be accurate enough to track the location of the gps and its movement
To be able to track the GPS through a broad range of location

Behavioral:

The person with the GPS can not notice the existence of the gps on themselves.
Provides an easy interface for the parent/tracker to track the gps.

ARCHITECTURE

USE CASES (INTERACTION DIAGRAMS)

SYSTEM STATES & TRANSITIONS

RISKS & MITIGATION STRATEGIES

Contained Risks Mitigation

GPS data unavailable for BHTX

Display last received data for RX

Cellular Network unavailable for BHTX

Display last received data for RX

Packets lost on way from BHTX through BHServer and BHRX

Resend packet data

BHRX attempts to wake up BHTX but fail

Reload last location and attempt to wake up again

Server fails

Attempt to send GPS data through SMS

Uncontained Risks

Multiple device failure

Complete network packet failure

Undetectable packet failure

Excessive punishment placed on unit

Failure of networking units

Contained Risks	Mitigation
GPS data unavailable for BHTX	Display last received data for RX
Cellular Network unavailable for BHTX	Display last received data for RX
Packets lost on way from BHTX through BHServer and BHRX	Resend packet data
BHRX attempts to wake up BHTX but fail	Reload last location and attempt to wake up again
Server fails	Attempt to send GPS data through SMS
Uncontained Risks
Multiple device failure
Complete network packet failure
Undetectable packet failure
Excessive punishment placed on unit
Failure of networking units