Real Time Location Systems (RTLS)
-
Upload
jeff-dungen -
Category
Technology
-
view
305 -
download
2
Transcript of Real Time Location Systems (RTLS)
Real Time Location SystemsAutomatic Identification and Tracking
© Jeffrey Dungen 2016
Purpose
© Jeffrey Dungen 2016
Is RTLS beneficial for my application?
What choices do I have among RTLS?
How do the different RTLS work?
What should I reasonably expect?
My Background
© Jeffrey Dungen 2016
Computer Engineer
RTLS, Geolocation & IoT startups since 2004
Applications from baggage to bike races...
DISCLOSUREI’m currently co-founder and CEO of reelyActive, an IoT/RTLS/M2M startup
Motivation
© Jeffrey Dungen 2016
Dots on a Map
© Jeffrey Dungen 2016
Is this what I expect?
Is this what I need?
Is this even what James Bond needs?
He/She/It isexactly here
RTLS for Humans
© Jeffrey Dungen 2016
“The nearest IV pump is in room 123A”➔ Can the nurse find room 123A?➔ Can the nurse find an IV pump in a room?
How should your RTLS effectivelyassist humans?
RTLS for Computers
© Jeffrey Dungen 2016
“RFID and sensor technology enable computers to observe, identify and understand the world—without the limitations of human-entered data.” — Kevin Ashton
How do computers understand identification & location?
Tech-First Approach
© Jeffrey Dungen 2016
1. What is technically feasible/appropriate?
2. Can my problem technically be solved with RTLS?
3. How do I deliver a solution?
In my experience, this is currently the approach which most reliably leads to real solutions. Of course, I’m an engineer...
Technology
© Jeffrey Dungen 2016
A Typical RTLS
© Jeffrey Dungen 2016
Middleware
Sensor Sensor Sensor
Tag TagTag Tag TagTag Tag TagTag Mobile
FixedInfrastructure
HostedOn-site
Identification
© Jeffrey Dungen 2016
Sensor
Tag
Passive RFID
Sensor
Tag
Active RFID
UHF
Infrared*SHFUHFUltrasound*
Energy sourcedfrom sensor
Energy sourcedfrom tag
*Not RF*Generalisation
10m*
Frequency Band
© Jeffrey Dungen 2016
TagSensor Sensor
Water Wall
Absorption Reflection2.45GHz is used by WiFi,
Bluetooth and to heat food...Higher frequencies
reflect more → Multipath
Narrow vs. Ultra-wide
© Jeffrey Dungen 2016
Tran
smis
sion
Du
ratio
n
Bandwidth
Narrowband
Ultra-wideband(UWB)
UWB transmissions are so short, they overcome reflections that affect the direct signal path.
Narrowband suffers what is called “multipath fading”.
RSSI
© Jeffrey Dungen 2016
Received Signal Strength Indication➔ Estimate distance to tag based on signal strength➔ Ubiquitous sensor support➔ Significantly affected by absorption and reflection
Tag Sensor
Distance
AoA
© Jeffrey Dungen 2016
Angle of Arrival➔ Estimate angle to tag based on phase shift on antennae➔ Requires multiple antennae per sensor➔ May require specific tag transmission sequence
Tag
Sensor
Angle
TDoA
© Jeffrey Dungen 2016
Time (Difference) of Arrival➔ Estimate (relative) distance to tag based on arrival time➔ Requires multiple time-synchronised sensors➔ May require significant computing in middleware
Tag SensorSensor
t1 t2t2 - t1 = 10ns = Δ10ft
Fingerprinting
© Jeffrey Dungen 2016
Leverage what you actually get➔ Calibrate based on actual sensor values (RSSI, etc.)➔ Granularity based on number of points observed➔ Changes in environment strongly impact results!!!
Sensor ARSSI
A = 150B = 100
RSSIA = 120B = 130
RSSIA = 110B = 160
Sensor B
Zone 1 Zone 2 Zone 3
Tech Summary
© Jeffrey Dungen 2016
1. Active RFID and UHF Passive RFID support RTLS
2. Frequency and environment affect performance
3. Various location techniques with tradeoffs
Configurations
© Jeffrey Dungen 2016
Checkpoint
© Jeffrey Dungen 2016
Sensors detect tags only through checkpoints.
What if a tag enters/leaves via another passage?
Detect passage through here
Visibility
Detect presence throughout
Sensors detect tags throughout the facility.Coverage overlaps.
Can coverage extend too far?
© Jeffrey Dungen 2016
Zone Location
© Jeffrey Dungen 2016
Tags are located to the nearest zone.
Zone definitions must take into account the technology and sensor placement.
The tag is in this zone
Precise Location
© Jeffrey Dungen 2016
Tags are located to precise coordinates.
Requires AoA or TDoA for the precision to meet reasonable
expectations.
The tag is exactly here
Config Summary
© Jeffrey Dungen 2016
1. Checkpoints only? Or visibility throughout?
2. Zone location good enough? Precision required?
3. A combination of all of these may be ideal!
Practicalities
© Jeffrey Dungen 2016
Tags
© Jeffrey Dungen 2016
Options limited by budget and config.➔ Passive may be only cost-effective high-volume option!➔ Active RFID performance vs. battery life➔ Proprietary Active RFID performance vs. vendor lock-in➔ Flexibility of Bluetooth/WiFi BYOD vs. performance➔ Radio compliance for the target geography?
Sensors
© Jeffrey Dungen 2016
Sensors need power & connectivity➔ PoE offers both on a single cable➔ Possible to get cable drops to the optimal locations?➔ WiFi/Mesh backhaul offers convenience over reliability➔ Is there a mains outlet at each optimal location?➔ Intentional or unintentional tampering?
Middleware
© Jeffrey Dungen 2016
Last but definitely not least!➔ Proprietary or open source?➔ Vendor lock-in or alternatives?➔ Who maintains and operates?➔ Runs on-site and/or in the cloud?➔ Total cost of ownership?
Practicalities Summary
© Jeffrey Dungen 2016
1. Tag selection may dictate the deployment!
2. Can I deploy the sensors as my needs dictate?
3. After all that, is there a middleware that fits the bill?
Examples
© Jeffrey Dungen 2016
Retail Inventory
© Jeffrey Dungen 2016
Back Store
Store(Visibility)
Receiving
Fitting Rooms
➔ Every article of clothing has UHF Passive RFID tag
➔ Visibility coverage in store ensures articles on display
➔ Fitting rooms zone location (requires radio shielding)
➔ Various middleware options
Hospital Staff & Equipment
© Jeffrey Dungen 2016
Room(Zone)
➔ Every equipment has an integrated BLE tag
➔ Staff use mobile app (BLE)➔ AoA sensors for precision
tracking in Triage Ward➔ Cost-effective BLE sensors
for visibility & room zones➔ Bespoke middleware
Room(Zone)Room(Zone)
Room(Zone)Room(Zone)Room(Zone)
Triage(Precision)
Courtyard(Visibility)
WIP Tracking
© Jeffrey Dungen 2016
Machine➔ Every employee has Active
RFID tag➔ Every WIP job clipboard has
Active RFID tag➔ Every machine has sensor➔ Open source middleware
Machine
Machine
Who’s applying which processto which job right now?
Examples Summary
© Jeffrey Dungen 2016
1. There’s no “one-size-fits-all” solution!
2. Each requires system integration and at least some custom application development.
3. None of these required “dots on a map”!
Conclusions
© Jeffrey Dungen 2016
Review of Purpose
© Jeffrey Dungen 2016
Is RTLS beneficial for my application?
What choices do I have among RTLS?
How do the different RTLS work?
What should I reasonably expect?
Managing Expectations
© Jeffrey Dungen 2016
It’ll likely take longer than you think, especially if process or behavioural changes are required!
BUT, a well-implemented RTLS will create efficiencies, streamline operations and provide a sustainable competitive advantage.
Thanks!
© Jeffrey Dungen 2016