Cost of Sensor Networks

Time

$

Computing Power

Sensors

Installation, Connection and Commissioning

Mesh Networking

Low Data Rate WPAN Applications (Zigbee)

RESIDENTIAL/LIGHT

COMMERCIAL CONTROL

CONSUMER ELECTRONICS

TVVCRDVD/CDremote

securityHVAClighting controlaccess controllawn & garden irrigation

PC & PERIPHERALS

BUILDING AUTOMATION

securityHVAC

AMRlighting controlaccess control

mousekeyboardjoystick

PERSONAL HEALTH CARE

patient monitoring

fitness monitoring

INDUSTRIALCONTROL

asset mgtprocess control

environmentalenergy mgt

Standards

• IEEE 802.15.4

• Zigbee

• TinyOS

• ISA SP100

• HART

Zigbee

• Zigbee 1.0 ratified in 2004 • Great marketing tool, but…

– Nothing interoperable yet– “Zigbee” products typically aren’t

• Everything shipped to date is IEEE 802.15.4 + proprietary MAC

• Lost industrial automation in 2005• Losing building automation in 2006?• Fighting Zensys in home automation• Latest: Zigbee Pro

– “The stack that works” – Hot debate on frequency hopping

University Demos – Results of 100 man-years of research

Intel Developers Forum, live demo800 motes, 8 level dynamic network,

Seismic testing demo: real-time data acquisition, $200 vs. $5,000 per node

vs.

50 temperature sensors for HVAC deployed in 3 hours. $100 vs. $800 per node.

Motes dropped from UAV, detect vehicles, log and report direction and velocity

What went wrong?

• Reliability• Power• Security• Cost• Size

Academic:• Repeatability• Intractability

– “It takes roughly 2.5 PhDs to get a new sensor network project to work. This has to change.” - Sam Madden, MIT

Reliability

• Understand the RF environment in the context of Murphy’s Law

• Use redundancy– Time– Frequency– Space

• Results: >99.9% end-to-end reliability in harsh environments

Power

200k Bit rate (bps)100k 300k

I RX (

mA

)

5

10

20

15

25

X cc1000

Molnar 04 (0.4mA)

X

X cc2420

XOtis 05 (0.4mA)

Cook 06 (300 W)

X

With software:10 years D cell

With software:10 years coin cell

Security

• AES 128– Confidentiality– Integrity– Authenticity

• Public Key Infrastructure– Certification– Key exchange

System Cost, 2005

• Single-chip mote– Processor, memory

– 2.4G radio (not 802.15.4)

– Software?

Single-chip $1.50

Passives $0.20

PCB Assembly & Test $0.20

Battery $0.10

Total $2

Chevron’s Richmond Refinery

1 km

Oil Refinery – Double Coker Unit

• Scope limited to Coker facility and support units spanning over 1200ft

• Expanded to 27 units, implemented 14 to start

• No repeaters were needed to ensure connectivity

• Gateway connected via Ethernet port in control room to process control network

• Electrical/Mechanical contractor installed per wired practices

GW

ISA Expo Wireless HART DemoOctober 2006

Emerson (Fully integrated + Battery powered)

Siemens (Fully Integrated + Battery powered)

Pepperl+Fuchs

ABB

Endress+Hauser

Honeywell

MACTek

PhoenixContact

Smar

Yokogawa

Siemens(Gateway + Mgmt)

Elpro

Wireless HART Demo, ISA Expo 2006

12 Manufacturers,1 Network – Dust Networks’ SmartMesh XT

Excerpts from Customer Presentations at the Emerson Process Users ConferenceOctober 2-5, 2006

Next generation capabilities• Coming soon:

– 32 bit ARM; 1MB flash; 64kB RAM– 2.4GHz RF, bps to Mbps, ~1nJ/bit– ~ s synchronization across network– ~ 1 meter location accuracy– < 10mm2

– 1A in-network average current consumption

• Baby version– 32 bit ARM; 128kB Flash; 8kB RAM– Same RF, same power– 2mm2?

~2 mm^2 ASIC

Mote on a Chip? (circa 2001)

• Goals:– Standard CMOS– Low power– Minimal external components

uP SRAM

RadioADC

Temp

Ampinductor

crystal

battery

antenna

~$1

Single-chip 802.15.4 motes

• Atmel

• Chipcon (TI)

• Ember

• Freescale

• Jennic

• Oki

• …