RFID Fall Detection Floor Mat System

RFID Fall Detection RFID Fall Detection Floor Mat SystemFloor Mat System

Andrew Heidt Andrew Heidt Brian TippinsBrian Tippins

Coleman McDanielColeman McDanielZach BrannanZach BrannanAbdirizak MireAbdirizak Mire

System OverviewSystem Overview

Detects patient falls using an RFID Detects patient falls using an RFID wrist tag and an antenna embedded wrist tag and an antenna embedded in a floor matin a floor mat

Is used in hospitals and elderly care Is used in hospitals and elderly care facilities, where falls are commonfacilities, where falls are common

Will cost $3,500 per unitWill cost $3,500 per unit

Design ObjectivesDesign Objectives

Detect patient falls and egressDetect patient falls and egress

< 5% detection failures< 5% detection failures

Notify staff of incidentsNotify staff of incidents

Record incidents in logfileRecord incidents in logfile

System DiagramSystem Diagram

RFID ReaderRFID Reader

Feig OBID i-Scan MR101-AFeig OBID i-Scan MR101-A Operating Frequency: 13.56 MHzOperating Frequency: 13.56 MHz Power Output: 1 WattPower Output: 1 Watt Output Impedance: 50 ohmsOutput Impedance: 50 ohms

Floor MatFloor Mat

Built with hard tapered edgesBuilt with hard tapered edges Contains antenna structureContains antenna structure Placed at patient bedsidePlaced at patient bedside

30”

48”

3”

AntennaAntenna

Copper foil antennaCopper foil antenna Resonant at 13.56MHzResonant at 13.56MHz Matched to 50 ohm readerMatched to 50 ohm reader

Antenna Design OptionsAntenna Design Options

Option 1: Single-loop antenna approximately the Option 1: Single-loop antenna approximately the area of the floor matarea of the floor mat

Option 2: Two antennas multiplexedOption 2: Two antennas multiplexed

Single-loop Multiplexed

Impedance Simulations (HFSS) Comparing Single-Impedance Simulations (HFSS) Comparing Single-loop and Multiplexed designsloop and Multiplexed designs

Single-loop Multiplexed

L= Z/(jω)=1.81 μH L= Z/(jω)=1.26 μH

Magnetic Field Simulations (HFSS) Comparing Magnetic Field Simulations (HFSS) Comparing Single-loop and Multiplexed DesignsSingle-loop and Multiplexed Designs

Single-loop Multiplexed

Summary of Antenna Design OptionsSummary of Antenna Design Options

Single-loopSingle-loop MultiplexedMultiplexed

ProsPros

Larger rangeLarger rangeLow costLow costSimpleSimple

Smaller inductance Smaller inductance (easier to match)(easier to match)

ConsCons Higher inductance Higher inductance (harder to match)(harder to match)

Multiplexing adds Multiplexing adds complexity and costcomplexity and costHigher failure rateHigher failure rateSmaller rangeSmaller range

Computer Interface: Process FlowComputer Interface: Process Flow

Interfacing with Hospital NetworkInterfacing with Hospital Network

Patient PCPatient PC• Logs incidentsLogs incidents• Displays fall alertsDisplays fall alerts• Transmits alerts to nurse stationTransmits alerts to nurse station

Nurse StationNurse Station• Displays fall alertsDisplays fall alerts• Adds/Removes patient informationAdds/Removes patient information

VB – Computer ImplementationVB – Computer Implementation

Patient PC functions:Patient PC functions:• Listener() – listens on serial port for tag Listener() – listens on serial port for tag

detectionsdetections• File_Logger() – logs detection incident File_Logger() – logs detection incident

with date/time in local filewith date/time in local file• Transmit() – forwards detection Transmit() – forwards detection

incidents and listen resets to the nurse incidents and listen resets to the nurse stationstation

• Alert() – displays alert window on PCAlert() – displays alert window on PC

VB – Computer ImplementationVB – Computer Implementation

Nurse StationNurse Station• Add(), Remove() – add and remove Add(), Remove() – add and remove

patients from the monitoring systempatients from the monitoring system• Edit() – edit patient information (name, Edit() – edit patient information (name,

room number, tag number etc.)room number, tag number etc.)• Ignore() – stops alerts for a specific Ignore() – stops alerts for a specific

patientpatient• Alert() – displays alert window with Alert() – displays alert window with

incident and patient informationincident and patient information

GUIsGUIs Nurse StationNurse Station

Patient PCPatient PC

CostsCosts

Expected Costs:Expected Costs: Updated Costs: Updated Costs:

Part Price

Feig Mid Range Reader $700

Floor Mat $100

Copper Foil $10

Cables $15

Capacitors $10

Resistors $2

Multiplexer* $50

Total $887

Part Price

Feig Mid Range Reader $532

Floor Mat** $100

Copper Foil $20

Cables $29.35

Capacitors $9.10

Resistors** $2

Monitor $120

PC $50

Total $862.45

* - We no longer anticipate the use of a multiplexer in the design

** - Estimated Cost

TimelineTimeline

Patient falls cost the health care Patient falls cost the health care industry $19.4 billion in each yearindustry $19.4 billion in each year