Wireless Sensor Networks Kris Pister Founder Chief Technologist

Wireless Sensor Networks Kris Pister Founder & Chief Technologist, Dust Networks (Prof. EECS, UC Berkeley)

Dust sells reliable, low power mesh networks to OEMs s M E O Users End

Evolving information flow in WSN Business logic Custom APP Manager LBR IPv 6, Proprietary network & data fmt. Network stack Mote DB Serial API Sensor Application m. P native DB fmt. Network stack Application Oski (SPOT-lite)? Sensor 3

Outline • Applications • Standards • Technology

Outline • Applications – Industrial Process Automation – Commercial Building Automation – Parking management – Smart Rail – Vibration monitoring – Smart Grid • Standards • Technology

Emerson Process offerings, 2007

Wireless HART Architecture (from ABB)

Sampling of Wireless HART Products ü Battery ü Vibration ü Battery ü 4 -20 m. A loop ü Solar ü Battery ü 4 -20 m. A loop ü Thermal Thousands of networks, dozens of countries, six continents buildings, breweries, refineries, mines, city streets, chemical plants, deserts, trains, steel mills, data centers, pharmaceutical plants, offshore oil rigs…

Wireless. HARTTM Adapters ABB Adapter Emerson THUM MACTek BULLET Siemens SITRANS AW 200

Wheeling-Pittsburg Steel Need to monitor temp, coolant, lubrication Hot slag defeated wired solutions 5% improvement in productivity (reduced maintenance) 10

Lime Kiln at Pulp & Paper Mill • Rotating lime kiln • Need to monitor temperature • 5% throughput improvement (reduced process time) 11

Grane Platform, North Sea • 22 pressure sensors • 90% reduction in installation cost Wireless Sensors 12

Shell Oil, Norway • GE Energy’s System 1 motor condition monitoring • 200 temperature and vibration sensors • No line power due to hazardous location rules Wireless mesh network 1 km 2 km

Chevron’s Richmond Refinery 1 km

Richmond Refinery Wireless Umbrella Next • Fence monitoring • H 2 S, VOC • Location 5 km 2, 90% coverage 15

Smart Building: Federspiel Controls HVAC optimization to conserve energy CA Tax Board savings: 459, 000 k. Wh/yr, $55, 000/yr (1 yr payback) No wires, no interruption to data center operations 16

Smart Cities: Streetline Networks Wireless sensor node 20

Urban Planning

Increasing Revenue

Finding Parking

Finding Parking

Smart Rail • TSCH WSN enables remote monitoring of freight cars • Multiple sensors per car, every car is a network • Requires a strict ‘nowires’ solution, robust enough for moving railcars

Bearing Failure High Cost

Vibration Monitoring

Smart Grid

Outline • Applications • Standards – TSMP – Zigbee – 802. 15. 4 E – IETF • Technology

Time Synchronized Mesh Protocol (TSMP & TSCH) • Basis of several Industrial Automation Standards – IEC 62591 (Wireless. HART) – ISA 100. 11 A – WIA-PA (China) • MAC is standardized in 802. 15. 4 E (TSCH) • Multiple network vendors: Dust, Nivis, STG, … • Best performance – – – Highest reliability Lowest power Lowest latency Largest scalability Accurate timestamps

Zigbee • The big three – Zigbee Pro / SE 1. 0 – Zigbee RF 4 CE • Home entertainment control • Guarantees that cell phones will have 15. 4 radios – Zigbee IP / SE 2. 0 • http, TLS, DHCP, … • Zigbee Green Power • All use powered routers – LPR getting little traction • Interoperability – AODV – Provisioning

802. 15. 4 E • A tale of four standards • PAR: “time synchronized channel hopping” “in support of industrial automation” – TSCH – LE – FA – DSME

IETF • 6 Lo. WPAN – IPv 6 adaptation layer • Ro. LL/RPL – Gradient routing • Co. RE/Co. AP • These are the building blocks – Zigbee IP / SE 2. 0 – Something with 802. 15. 4 E?

Protocol Integration Application Presentation Session “other” HTTP, SSH, Telnet, FTP Co. AP, XML, IETF Transport UDP , TCP WSN RDP? Network IPv 6 Ro. LL RPL Data-Link Physical 6 Lo. WPAN IEEE 802. 3 IEEE 802. 11 802. 15. 4, 4 e 802. 15. 4 Today’s Internet Tomorrow’s Internet of Things

Outline • Applications • Standards • Technology – TSMP – Oski – SPOT

TSMP Foundations • Time Synchronization – Reliability – Power – Scalability • Reliability – Frequency diversity • Multi-path fading, interference – Spatial diversity • True mesh (multiple paths at each hop) – Temporal diversity • Secure link-layer ACK • Power – Turning radios off is easy

Power-optimal communication • Assume all motes share a network-wide synchronized sense of time, accurate to ~1 ms • For an optimally efficient network, mote A will only be awake when mote B needs to talk A A wakes up and listens B B transmits B receives ACK A transmits ACK Expected packet start time Worst case A/B clock skew

Packet transmission and acknowledgement Mote Current Radio TX startup Packet TX Radio TX/RX turnaround (2011): 15 m. C ACK RX (2008): 50 m. C Charge cost (2003): 300 m. C

Idle listen (no packet exchanged) Mote Current Radio RX startup Empty receive (2011): 5 m. C (2008): 27 m. C Charge cost (2003): 70 m. C

Mesh Networking IP Gateway IEEE 802. 15. 4 Mote Sensor • 802. 15. 4 PHY, 2. 4 GHz • Time Synchronized for low power & scalability – All nodes run on batteries, for 5 -10 years • Channel Hopping and full mesh for reliability – 99. 999% “best effort” packet delivery

Relative time error 2 hops, low traffic Room temperature • Simulated. 8 hops, low traffic Extreme temp 8 hops, high traffic Extreme temp

Absolute time synch Stratum 1 server NTP PM or LM Mote • Relative error: 0. 1 ms avg. , 1 ms max • Absolute error on PM: • 0. 3 ms avg. ; 99. 9% <1 ms; 10 ms worst case • 1 us w/ 1588 42

Evolution of a mote

Oski • Future-proof horsepower – 32 bit ARM Cortex M 3 – 512 k. B flash, 72 k. B RAM • Revolutionary radio & network – – IPv 6 router < 20μA 10 years with an AA lithium battery Microsecond timestamps Location • Fast application development • Multi-protocol routing – 6 Lo. WPAN – Zigbee SE 1, 2; Pro – HART

Measured time updates: <1 us on average

Mote-on-chip current vs. sample date RX Current TI MSP 430 +CC 2420 Jennic CEL Ember 0 d. Bm TX Current Freescale TI Freescale Dust Networks Ember Jennic Dust Networks

Location • RTLS costs often dominated by infrastructure – Power and/or data cabling for readers • Barrier to initial deployment 47

Smart. Mesh SPOT Asset Management System & Location Engine Network Manager Locn: Room 327, west wall Fixed Battery Powered Mote 27. 2 m 22. 5 m 40. 1 m Mobile Mote 17. 8 m 23. 2 m Sensor 48 48

Smart. Mesh SPOT Advantages • No site survey – Field-proven, self-forming, self-healing TSCH mesh • No wires – Battery/scavenger-powered “peel-and-stick” infrastructure • …and a true IP network – Sensors: button, temp, shock, … – Outputs: displays, alarms, …

Theory only goes so far Dr. Mark Lemkin Dust Networks’ Lead RF designer Dr. Lance Doherty Dust Networks’ System Architect 50

RLOP 1 View from top View from bottom 51

RLOP 2 “Ceiling” of pipes We instrumented this roadway 52

View up from second floor Mark with Master and Slave co-located 53

Warehouse 4 motes in 4 corners All master positions inside All slaves at approx same y level 54

Test Results 2. 4 ft error 2. 1 ft error Repeated testing in various indoor/outdoor venues confirms 1 -3 m accuracy even in the harshest RF environment

Estimate over time

Estimate vs. # reference nodes

Error estimate dark blue=confident; red=not confident

Preliminary Results Accuracy with 25 ms measurement • Multi-path cable tests show ~1 m • Outdoor uncluttered ~1 -2 m • Indoor cluttered ~2 m • Oil refinery ~3 m 59

Summary • Real applications exist • Standards are a reality • Existing products have high reliability and low power • Low-infrastructure localization is coming