Transcript Final Project Presentation - Georgia Institute of Technology

Smart Mattress
Bryan Kuo, Priyen Patel, Dev Shah, Xitij Shah, Tim Stamm
Georgia Institute of Technology
December 5, 2008
Project Overview
 Goals:
 Prevent bedsores acquired on hospital/nursing home beds
Wetness Detection
Inactivity Detection
 Prevent incorrect medication administration
Patient Identification System
Patient Barcode Display
 Clients:
 Hospitals
 Nursing Homes
 Cost: $1,055
Design Objectives
Identify patients using RFID
Display patient information and barcode
on a PC monitor
Detect moisture and patient inactivity that
could cause bed sores
Alert staff if patient is in danger of
developing bed sores
Overall System - Current
Overall System - Current
Previous RFID System
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Passive RFID System
OBID i-scan HF RFID Reader
OBID i-scan HF Pad Antenna
RFID Operating Frequency: 13.56 MHz
RFID Antenna Range: 7 in.
RFID Transmitting Power: 1W ± 2 dB
* Note: This range did not meet our specifications
Current RFID System
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Active RFID System
Wavetrend RX201 Active RFID Reader
Wavetrend AN100 Active Whip Antenna
RFID Operating Frequency: 433 Mhz
RFID Antenna Range: 35 ft
RFID Wavelength: 2.3 ft
Tag Battery Life: 5 years
RFID System
 RFID antenna located at foot of bed
 Wavetrend Active RFID tags
 Patient tag compared to patient ID database
 Patient name and barcode displayed on PC
RFID Tag
Reader and Antenna
HP Slimline PC
RFID Detection Range
Inactivity Monitoring System
Inactivity Monitoring System
Wetness Detection
 2 conductive loops of
tape connected to
wetness detection
circuit
 1st comparator input
monitors moisture
 2nd comparator
detects breaks in the
conductive loop
Wetness Detection System
Phidget 8/8/8 Interface Kit
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Interface between inactivity monitoring
and wetness detection systems with HP
Slimline PC
4 analog inputs for FSR strips
1 analog input for sampling wetness
detection circuit output
Current Status
 Wetness detection system
 2 conductive loops, comparator, and 2 9V batteries
 Successfully implemented and tested on breadboard
 Inactivity monitoring system
 4 Trossen Robotics force sensing resistor strips
 Controlled through Phidget 8/8/8 interface kit
 Successfully implemented and tested
 RFID System
 Wavetrend Active RFID Reader/Antenna
 Successfully implemented and tested
Design Specifications
Technical Specifications
Proposed
Actual
RFID Reader
RFID Operating Frequency
13.56 MHz
433 MHz
RFID Transmitting Power
1W ± 2 dB
N/A
Max RFID Reading Distance
1 ft (12 in.)
35 ft.
RFID Current Draw
Max. 0.5 A
Multiplexer
Microprocessor
PIC18 LF2321
Phidget 8/8/8 Interface Kit
Power Supply
3.3 V
2 9V batteries
Current Consumption
< 5mA
Switching Loop-time
16 ms
Same
Force Sensitivity Range
0 to 1000 lbs
Same
Pressure Sensor Range
1.5 to 150 psi
Same
Trossen Robotics 24” FSR
Competing Products
Total Care SpO2RT Hospital Bed
$28,500
Secure II Med/Surg Hospital Bed
$10,000
Cost
Part
Quantity
Unit Cost
Total Cost
FSR Robotics Sensor Kit
4
$27
$108
Phidget 8/8/8
1
$80
$80
Wires/Cables
1
$15
$15
9V Battery
2
$7.50
$15
RFID Tag and Reader
1
$307
$307
75ft
$50
$50
Mattress Foam
1
$150
$150
Bed Sheet
1
$30
$30
HP Slimline PC
1
$250
$250
PC Monitor
1
$50
$50
Conductive Tape
Total Equipment Cost
$1,055
Selling Points
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Lower cost
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Portable
More versatile
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Costs $1,055
Competitor products cost at least $10,000
Combines wetness and inactivity detection
Utilizes RFID to prevent improper
medication administration
Appealing Graphical User Display
Future Considerations
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Use a smaller, cheaper microcontroller
such as a PIC
Implement systems on a PCB
Find smaller wrist/ankle band active
RFID tags
PIC Microcontroller
 Used for integrating wetness
detection, inactivity monitoring,
and patient identification systems
into a low-cost power-efficient
package
 Low power operation using 3V
coin cell battery
 Programmed in C via 6-pin header
through PICkit2
 RS232 communication to PC using
onboard UART
 Pushbutton and LED for
debugging
PIC for Inexpensive System
Integration
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RFID
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Inactivity monitoring
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Sample force sensing resistors using
onboard ADC
Wetness detection
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Implement either using RS232 with current
reader or SPI enabled reader
Sample output of comparators using digital
input
LCD for display of system status
Demonstration Plan
 Inactivity Detection
 Group member lays for extended period of time.
 LCD monitor displays inactivity alarm
 Patient Identification
 RFID tag located within antenna range
 LCD monitor displays patient name
 LCD monitor displays patient medication barcode
 Wetness Detection
 Salt water poured on bed
 LCD monitor displays wetness alarm