Transcript Mobile Phones: Enabling Next Generation Gerontechnologies

Mobile Phones:
Enabling Next Generation
Gerontechnologies
Sean J. Barbeau
Research Associate
Center for Urban Transportation Research
College of Engineering
University of South Florida
Topics
 Overview of today and tomorrow’s mobile
phone technology
 Example: The Travel Assistant Device
 Challenges with Real-time Mobile Applications
 Conclusion
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Opportunities
 3.25 billion wireless subscribers (½ of world’s population)
 Many methods of communication on cell phone (sounds,
pictures, video, touch) for advanced user interfaces

Key to reaching the elderly population who are not “digital natives”
 Cell Phones can help ease the aging process:

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Real-time transit navigation for individuals that can no longer drive
Bluetooth hearing aids allow phone conversations for hearing-impaired
Tracking systems to monitor health/location of early-stage dementia
patients
Medication reminders – Instantly update after doctor’s visit
Allows individuals to remotely check on elderly parents
 Real-time assistance and monitoring can:


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Enhance individual’s quality of life
Prolong the individual’s independence
Delay institutionalization and full-time care
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Mobile Technology
 Cell Phones are the first widely distributed
mobile devices that are:
 Affordable
 Programmable
 Java for mobile devices = J2ME
 Always connected
 Almost any software application can be
adapted for cell phones
 Previously separated from Internet, but now
connected
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Mobile Technology
 Today, many cell phone data communications are
IP-based:
 Browsing the web
 Accessing email
 Installed client applications talking to a server
 Current Java-enabled cell phones must support
HTTP, many also support TCP and UDP
 However, most voice calls are not IP-based
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Mobile Technology
 Tomorrow: IP Multimedia Subsystems (IMS)



Everything-over-IP (Voice, Video, etc..)
Network and Technology Agnostic
Allows voice and data services simultaneously
 Sessions (via SIP) hold information on users:
 Device Capabilities
 Presence (Online or Offline)
 Location (Geographic Coordinates)
 A user can move from one device or network to another during a
session. Examples:


Cell phone switches from using cellular network to your WiFi network
when you arrive home without interruption
You’re on your work phone with a colleague but need to leave the
office. Call is instantly transferred to your cell.
 Cell Phones become a true mobile extension to the Internet
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Mobile Technology
 Network evolution reaching broadband speeds
 Ex. CDMA data rates (Sprint, Verizon):
CDMA2000
1XRTT
EVDO REV-0
EVDO REV-A
WiMAX
(Sprint =
“XOHM”)
Download rate
Up to 150
kbps
Up to 2.5 Mbps
Up to 3.1 Mbps
Up to 5
Mbps
Upload rate
Up to 150
Kbps
Up to 150 Kbps
Up to 1.8 Mbps
Up to 1-2
Mbps
Avg. data rate
50 – 75
Kbps
300 –600 Kbps
(Download)
50 - 75 Kbps
(Upload)
600 – 1300 Kbps
(Download)
200 – 500 Kbps
(Upload)
Now
End of 2007
End of 2008
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Mobile Technology
No Network? – No Problem!
 Bluetooth

Short-range (30ft) technology used to transfer information
between 2 devices

Phone-to-Phone

Phone-to-hearing aid

Phone-to-health monitor
 Near-Field Communication (NFC)


Allows you to “swipe” your cell phone

Buy things, prove your identity, etc.
Now available in U.S. phones
Source: Cristina Martinez Byvik
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Mobile Technology
Global Positioning System
(GPS)





Device uses satellite signals to
determine its current location
Accurate up to 3-5 meters
Small enough to manufacture
as a “chip” inside phone
Assisted GPS (aGPS) uses
data provided by the cellular
network to reduce time-to-firstfix
Enables Location-Based
Services (LBS)
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Travel Assistant Device
(TAD)
 Helps guide transit riders with cognitive
disabilities
 Used by Travel Trainers (Employees of
transit agencies who introduce new riders
to transit)
 Keeps rider safe and eases parental
anxieties
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“Travel Assistant Device”
for Special Needs Riders
 Scenario: Joe needs to get from Home to Work and back using
transit
Bus Stop B
Home
Work
Bus Stop A
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“Travel Assistant Device”
for Special Needs Riders
 Most of the time Joe gets off at the right stop, but sometimes he
forgets to pull the stop handle.
Bus Stop B
Home
Work
Bus Stop A
Joe
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“Travel Assistant Device”
for Special Needs Riders
 Let’s try again, this time with a “Travel Assistant Device”. Joe’s
cell phone will ring and vibrate when the bus is approaching the
“Reminder A” location, prior to his bus stop.
Reminder A
Home
Bus Stop B
Work
Bus Stop A
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“Travel Assistant Device”
for Special Needs Riders

When his phone rings, Joe remembers to pull the stop handle. Joe
arrives safely at the correct bus stop.
Reminder A
Home
Bus Stop B
Work
Bus Stop A
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“Travel Assistant Device”
for Special Needs Riders
 A second reminder can be established for her ride home.
Reminder A
Bus Stop B
Reminder B
Home
Bus Stop A
Work
“Travel Assistant Device”
for Special Needs Riders
 Joe arrives home safely. The reminders are triggered by his
location, so time of day doesn’t matter.
Reminder A
Bus Stop B
Work
Reminder B
Home
Bus Stop A
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“Travel Assistant Device”
for Special Needs Riders
 Alarms is triggered if a rider deviates from their planned route.
 Can use multimedia alarms & reminders:


Play a recorded audio message.
Show a picture/video of the next stop or landmark.
Travel Trainer
Alarm A
Home
Bus Stop A
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“Travel Assistant Device”
for Special Needs Riders
 Travel Trainers and Caretakers can instantly see where the rider is
currently located by using a web page.
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Challenges
 Cutting-edge and next-generation
“Gerontechnology” systems will be driven by
real-time access to information
 Networked mobile applications are inherently
different from traditional networked
applications
 Need to solve new problems!
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Challenges
 Power, a very limited resource, is consumed by:

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CPU calculations
Wireless transmissions
GPS fixes
 Wireless transmissions:

Communication often fails
 Reliable protocols (i.e. TCP) cause multiple re-transmissions
 Retransmissions drain battery, and aren’t useful for real-time LBS

Every bit transferred costs power
 But so does using compression algorithms

Every bit transferred costs $
 GPS

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Every fix costs power
GPS signals aren’t always available
 Attempting to get a fix while indoors can result in large power costs
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Challenges
4
3
2
1
0
17533
16072
14611
13150
11689
10228
8767
7306
5845
4384
2923
1462
Batt. Lv.
1
Battery Power
 GPS fix + UDP Transmission every 4 seconds
 Battery lasts 5.06 hrs
Battery Level vs Time
Time in Seconds
4
3
2
1
0
Batt. Lv.
1
29
23
58
45
87
67
11
68
9
14
61
17 1
53
20 3
45
23 5
37
7
26
29
29 9
22
32 1
14
3
Battery Power
 GPS fix + UDP Transmission every 30 seconds
Battery Level vs Time
 Battery lasts 9.6 hrs
Tim e in Seconds
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Solutions
 “Critical Point Algorithm” – only send GPS
points that are required to reconstruct a trip

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Don’t send coordinate on every fix
Vary GPS refresh rate if possible
Check cell signal availability before sending
data
Without Critical Point Algorithm
With Critical Point Algorithm
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Solutions – “Critical Point”
Without Critical Point Algorithm
With Critical Point Algorithm
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Solutions – “Critical Point”
Trip
Number of
Trip Points
Number of
Critical
Points
Bytes
saved
Financial
savings*
1
73
26
5593
$0.17
2
363
56
36533
$1.10
3
489
65
50456
$1.50
4
208
73
16065
$0.48
5
357
62
35105
$1.05
6
2320
159
257159
$7.71
7
1022
139
105077
$3.15
8
811
137
80206
$2.40
*Based on 119 bytes per UDP package and a charge of $0.03 per kilobyte.
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Conclusions
 Mobile phones are enabling new
“Gerontechnologies”
 All IP-based future means cell phones will be
seamlessly integrated with networks
 However, mobile applications are subject to
new problems!
 Recognizing these problems and creating
solutions leads to successful applications
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Thanks!
Sean J. Barbeau
Research Associate
Center for Urban Transportation Research
University of South Florida
4202 E. Fowler Avenue, CUT100
Tampa, FL 33620-5375
(813) 974-7208
(813) 974-5168 (fax)
[email protected]
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