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: 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: 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): Download rate Upload rate Avg. data rate
CDMA2000 1XRTT EVDO REV-0
Up to 150 kbps Up to 150 Kbps 50 – 75 Kbps Up to 2.5 Mbps Up to 150 Kbps 300 –600 Kbps (Download) 50 - 75 Kbps (Upload) Now
EVDO REV-A
Up to 3.1 Mbps Up to 1.8 Mbps
WiMAX (Sprint = “XOHM”)
Up to 5 Mbps Up to 1-2 Mbps 600 – 1300 Kbps (Download) 200 – 500 Kbps (Upload) 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-first fix 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 Work Home 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 Work Home
Joe
Bus Stop A
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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 Bus Stop B Work Home 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 Bus Stop B Work Home 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 Work Home Bus Stop A Reminder B
“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 Home Bus Stop A Reminder B
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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: 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 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
GPS fix + UDP Transmission every 4 seconds Battery lasts 5.06 hrs Battery Level vs Time 4 3 2 1 0
Tim e in Seconds
GPS fix + UDP Transmission every 30 seconds Battery lasts 9.6 hrs Battery Level vs Time 4 3 2 1 0 1 2923 5845 8767 11 68 9 14 61 1 17 53 3 20 45 5 23 37 7 26 29 9 29 22 1 32 14 3
Tim e in Seconds
Batt. Lv.
Batt. Lv.
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Solutions
“Critical Point Algorithm” – only send GPS points that are required to reconstruct a trip 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 2 3 73 363 489 26 56 65 5593 36533 50456 $0.17
$1.10
4 5 6 208 357 2320 73 62 159 16065 35105 257159 $1.50
$0.48
$1.05
$7.71
7 8 1022 811 139 137 105077 80206 $3.15
$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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