Real Time Location Systems (RTLS)
- 1. Real Time Location Systems Automatic Identification and Tracking © Jeffrey Dungen 2016
- 2. 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?
- 3. My Background © Jeffrey Dungen 2016 Computer Engineer RTLS, Geolocation & IoT startups since 2004 Applications from baggage to bike races... DISCLOSURE I’m currently co-founder and CEO of reelyActive, an IoT/RTLS/M2M startup
- 4. Motivation © Jeffrey Dungen 2016
- 5. 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 is exactly here
- 6. 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 effectively assist humans?
- 7. 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?
- 8. 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...
- 9. Technology © Jeffrey Dungen 2016
- 10. A Typical RTLS © Jeffrey Dungen 2016 Middleware Sensor Sensor Sensor Tag TagTag Tag TagTag Tag TagTag Mobile Fixed Infrastructure Hosted On-site
- 11. Identification © Jeffrey Dungen 2016 Sensor Tag Passive RFID Sensor Tag Active RFID UHF Infrared* SHF UHF Ultrasound* Energy sourced from sensor Energy sourced from tag *Not RF *Generalisation 10m*
- 12. Frequency Band © Jeffrey Dungen 2016 TagSensor Sensor Water Wall Absorption Reflection 2.45GHz is used by WiFi, Bluetooth and to heat food... Higher frequencies reflect more → Multipath
- 13. Narrow vs. Ultra-wide © Jeffrey Dungen 2016 Transmission Duration 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”.
- 14. 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
- 15. 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
- 16. 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 t2 t2 - t1 = 10ns = Δ10ft
- 17. 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 A RSSI A = 150 B = 100 RSSI A = 120 B = 130 RSSI A = 110 B = 160 Sensor B Zone 1 Zone 2 Zone 3
- 18. 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
- 19. Configurations © Jeffrey Dungen 2016
- 20. Checkpoint © Jeffrey Dungen 2016 Sensors detect tags only through checkpoints. What if a tag enters/leaves via another passage? Detect passage through here
- 21. Visibility Detect presence throughout Sensors detect tags throughout the facility. Coverage overlaps. Can coverage extend too far? © Jeffrey Dungen 2016
- 22. 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
- 23. 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
- 24. 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!
- 25. Practicalities © Jeffrey Dungen 2016
- 26. 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?
- 27. 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?
- 28. 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?
- 29. 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?
- 30. Examples © Jeffrey Dungen 2016
- 31. 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
- 32. 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)
- 33. 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 process to which job right now?
- 34. 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”!
- 35. Conclusions © Jeffrey Dungen 2016
- 36. 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?
- 37. 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.
- 38. Thanks! © Jeffrey Dungen 2016