New Wrinkles on RFID at the MIT Media Laboratory

Joe ParadisoResponsive Environments Group, MIT Media Lab

http://www.media.mit.edu/resenveBusiness 11/04

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Outline

• Passive Tags as sensors• Alternative “RFID “ modalities• Applications and Media-Lab startups in RFID

Note: This talk will review both recent and legacy work

Smart Sensors and HCI

• Ubiquitous Computing (PARC/Weiser)• Things That Think (ML)• Disappearing Computer (EU)• Invisible Computing (Microsoft)• Pervasive Computing (IBM)

• Electronics are cheaper, smaller, more capable, lower power...– Intelligence, sensing, communication, processing…

• Move off desktop into "things” & environments• Entirely different “input devices” & modalities enabled

Shift toward fine-grained, distributed interfaces

Sensing, communications, power management are key

Beaming Power

Bill BrownMicrowave-powered helicopter, 1964

Wireless humidity sensorMartinez, 2002 RFID Tags

• Beaming power has a long history (Tesla, etc)• Rectannas can approach 80-90+% efficiency• Low power apps common in everyday environments

– RFID (chips use 1 to 100 µW)• RF-powered sensors coming off the horizon

– Passive LC and SAW devices, sensor chips– Wireless tire pressure and tire friction sensors– Implantable sensors for monitoring blood pressure at the heart

Smart, Passive Objects

• ID, sensors in passive objects remotely interrogated– Tangible bits with no batteries, wires, line-of-sight!

Noncontact ID and Sensing

Resonance = f(T,P,F,a,...)

• Remotely power CMOS chip• Smart badges, cards, animals• Expensive (25¢, maybe 5¢)• Many bits of ID (e.g., 32-1K)• Anticollision time consuming• No continuous control• Special designs to sense

LC Tag

Shoplifting TagsChip Tag• Remotely excite resonant structure• Anti-theft detection (to 12 ft.)• Cheap (1¢) • Limited bits of ID (e.g., 5-6)?• Read all at once w. swept reader• Fast (present model runs at 30 Hz)• Easily used as remote sensors

Printed Electronics!

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Tags as Sensors (non ML)• SAW-based wireless pressure sensors

– A. Pohl, R. Steindl, and L. Reindl. The ’intelligent tire’: Utilizing passive SAW sensors-measurement of tire friction. IEEE Transactions on Instrumentation and Measurement, 48(6):1041–1046, 1999.

– C. McLeod, R. Dickinson, A. Sabkha, and C. Tormazou. Applications for implantable SAW pressure sensors. In Proc. of the International Workshop on Wearable and Implantable Body Sensor Networks, pages 22–23, London, April 6-7 2004. Imperial College.

• SAW-based wireless dosimeters• Crystal Resonator-based pressure sensors

– O. Bartels. 6,378,360: Apparatus for wire-free transmission from moving parts. US Patent, April 30 2002.

• RF-scattering tag proximity indicators– K. Fishkin, B. Jiang, M. Philipose, and S. Roy, “I Sense a Disturbance in the

Force,” Proc. of Ubicomp 2004, pp. 268-282.

• LC Parametric Resonators– W.B. Spillman Jr., S. Durkee, and W.W. Kuhns. Remotely interrogated

sensor electronics (RISE) for smart structures applications. In Proc. of the SPIE Second European Conference on Smart Structures and Materials (Glasgow UK), volume 2361, pages 282–284. SPIE, October 1994.

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Tagged Objects as Passive Trackers

Wacom Tablet• LC tags in pens ID’ed& tracked across multiple coils in tablet

Zowie GameLC tags in toys ID’edand tracked across multiple coils in board

Both close-rangeinteractions

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Tagged Objects as a Musical Controller

Don Buchla’s Marimba LuminaLC tags in mallets detected and tracked by multiple coils below pads

Close-range interaction (trigger with close z, track in x,y)

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Parametric Magnetostrictors

Rich Fletcher’s early demos in the Physics & Media Lab circa 1995

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Noncontact Sensing in an Old Shoe

Resonance = f(P)

Rich Fletcher’s shoe w. embedded pressure-sensing tag circa 1995

Ringdown Tag Readers

• Very simple, inexpensive prototype tag reader detects magnetostrictor (Sensormatic UltraMax) shoplifting tags– In-store sysems can reach circa 12 feet in range– High-Q mechanical structures (not so good with LC)– By cutting tag to different lengths, we get several (4-6) bits of

very cheap ID• Slow

– Must sit at frequencies of interest and interrogate

Media Lab Ringdown Prototypes

Paradiso & Hsiao1997 Prototype, running 30-150 kHz

Triac-switched capacitor ladder for tuning search coil on transmit, Comp. MOSFET drivers

Potentially good range, but slowResponse (e.g., 10 ms/tag)

Early (1995) ML Lego Demo

MagnetostrictiveResonator (60 kHz)

LC(- 200 kHz)

Tags Present Tags Absent

• Pickup coil under LEGO platform- Drive frequency swept 40 - 300 kHz- Resonant loading detected => tag identified

Swept-Frequency Tag Reader

• Looks for magnetically-coupled resonant loads from 50-300 KHz• Early EAS systems, “Grid-Dip Meter”• Simple, cheap, fast, but limited range

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Music Bottles

• Ferrite in bottlecap detunes LC coil wound around neck• Current installation at Ars Electronica Center, etc.

Hiroshi Ishii & Tangible Media Group

Resonant Frequency is “ID”Pick L,C or cut resonant strip

Tagged Objects

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Multiple modes of controlIncrease read range and # objects

Now 20 tags in system and 16 objects

• Wearable Ring tags– Continuous control on each finger (no glove)

• Tags that sit in reader area– Set background, context…

• 3-axis tags (respond to orientation and range)– Can be rolled around or manipulated

• Local sensor tags– Respond to pressure (or pull, etc.) and displacement

Many degrees of control…

Swept Tags as a Musical Controller

Inspired by John Zorn’s early Performances

Actual Baseline - Antilog SweepTags characterized by center frequency & area of corresponding peak

400 Khz 50 Khz

No Tags Pumpkin Only

Red Ring, Block Face, Dinosaur All Rings, Goblin, Corn, Dinosaur

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Tag Proximity Sensing

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LC Resonator in Cube

MagnetostrictorTag

Cup Coil

Saturation

zm

easu

red

(V-m

s)

-1/6

4.5 cm

Cup Coil

MagnetostrictorCube with 3 tags

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4Cube Signals

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Cup Signals

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Tag Angle Sensing

40 80 120 160 200 2400

1

2Integrated Tag Peaks vs. Rotation Angle

Rotation Angle (degrees)

Volt-

ms

0

2040

6080

100Reconstructed Absolute Angle vs. Rotation Angle

Rec

onst

ruct

edA

ngle

(deg

rees

)

40 80 120 160 200 240Rotation Angle (degrees)

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Tag Pressure Sensing

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Musical Trinkets

Emerging Technologies - SIGGRAPH 2000

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Natural Group Interaction

EMP Seattle, April 2001SMAU Convention, Milan, October 2000

SIGGRAPH, July 2000 (3:55) Demoed by John Zorn

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Musical NavigatrixLaurel (Pardue) Smith’s Meng, 2001

- Multicoil tracking (Olympics)- X,Y,Z sensitivity- Can lock tag response w. switch- Control musical parameters at

high level (sequences, timbres)- Can record, overdub actions

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SenseTable

• Tracks tagged pucks across 2D surface• Multiple tags per puck sense rotations in plane• Many applications (AudioPad, supply-chain, etc.)• Uses Zowie tracker (Scientific Generics)James Patten, Hiroshi Ishii – Tangible Media Group

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Multiaxis tag tracker

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Low-Cost Active Magnetic Tracking

MOMA Installation, 1-4/01

PDA Coils

Base Coils

AtmospheresCollaboration with ACG group

And Steelcase, Inc.

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Personal Area Network (PAN)Personal Area Network: Using the body as a common wire

• "Transmit" mode can be used to send data to other devices on body

• Low frequency (200 kHz) – λ ≅ 1 mile, Capacitive coupling,

near-field, 1/r3, little regulation, 19.2 kbaud

• Signal sent to objects when touched• To other people with a simple

handshake

Myriad social implications & applications...

• Business card exchange and transactions with a handshake• Doors, computers, phones, smart objects unlock to touch

Body gains second “nervous system” for wearable devices

Tom Zimmerman, MS thesis, '95

PAN Touch Communication

Note: PAN transceiver can be embedded in PC keyboard

The PAN Handshake

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Reader in Table

Reader in Your Shoe

Current channeled through bodyactivates passive tagCrystal resonator for high-Q

Ben Vigoda, Baback Nivi – Physics & Media Group

TouchTags

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Motorola BiStatix Tag

• Use Electric (as opposed to magnetic or RF) fields to power and read tag– Inexpensive (no coil needed, printed antenna)– Airline luggage tags, postal applications, etc.

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QuasiPassive Wakeup for wireless sensorsPower Ground Daughter

Sensor Low Power Comparator

Processor + Transceiver

RCL Filter (Optional)

2.4GHzSignal/Offset

Signal/Offset WakeupSignal/Offset

Programming Lines and Reset

Bypass

Bypass

• Takes data from variety of sensors– Built-in connection for accel, tilt, mic, pressure– Can also connect daughter board

• Passes through (optional) passive analog filter to low-power comparator

– Approximately 0.5 uA continuous draw• Comparator triggers wakeup of combined

processor/transceiver– Data analysis (if nec.) performed and message sent

Optical Tagging: The FindIT Flashlight

• Find objects from 10 feet away with 8-bit optical code

• Quasi-passive wake up to coded optical beam– Passive analog filter selects carrier, ultralow

power comparitor does the carrier detection• No active linear elements

• Respond by a flashing LED• Ambient current draw: 500nA• Runs up to 10 years on a lithium coin cell• Works where RFID can’t (metal, etc.)

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Wakeups per Month

Tota

l Bat

tery

Life

(Yea

rs)

Top: Flash LED every time tag interrogated

Bottom: Flash LED only with match

The Disposable Wireless Sensors

• Very simple “featherweight” motion sensor– Cantilevered PVDF piezo strip with proof mass– Activates CMOS dual monostable when jerked– Sends brief (50 µs) pulse of 300 MHz RF– 100 ms dead timer prevents multipulsing– Can zone to within ~10 meters via amplitude– Ultra low power – battery lasts up to shelf life– Extremely cheap – e.g., under $1.00 in large quantity

MIT PlaceLab

• Instrument Occupant – High-rate TDMA wearable

• Instrument Environment – Many minimal wireless “post-it” sensors– Power scavenge or quasi-passive wakeup

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Human Schooling

• People tend to synchronize response in crowds– Applause studies– People spontaneously synch up– Applause rate tends to increase before becoming chaotic and

starting over• Ways to electronically tap this reflex

– Interactive entertainment for large groups…

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Interactive Raves at MIT

Activity (# hits per 10 seconds) FFT (Tempo)

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Parasitic Power Harvesting Book Chapter

• Chapter in “Low Power Electronics Design”– Encyclopedic history and state-of-the-art of power

harvesting for mobile systems – To appear by summer 2004– Christian Piguet, editor – CRC Press

Power Harvesting ShoesPVDF Stave

Molded into soleEnergy from bend

Ppeak ≅ 10 mW<P> ≅ 1 mW

Flex PZT UnimorphUnder insole

Pressed by heelPpeak ≅ 50 mW<P> ≅ 10 mW

Responsive Environments GroupMIT Media Lab

1998 IEEE Wearable Computing Conference

Raw Powercirca 1% efficient

unnoticable

Application: Batteryless RFID Tag

• Use Piezo-shoes to charge up capacitor after several steps• When voltage surpasses 14 volts, activate 5 V regulator

– Send 12-bit ID 6-7 times with 310 MHz ASK transmitter• After 3-6 steps, we provide 3 mA for 0.5 sec

– Capacitor back in charge mode after dropping below output

Responsive Environments Group - MIT Media Lab

The Self-Powered Wireless Switch

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Time (msec)

Volta

ge (V

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Strike OccurrenceTank Capacitor Voltage

3 Volt Regulator Output

Serial ID Code

The Self-Powered Switch

2001Feldmeier & Paradiso

(2004 version)

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Window Switch with ALPS Automotive

• Command window up-stop-down• No battery, no wire

– Power harvested from single push– Eliminate need for complex wire harness

Mark Feldmeier

Application of Domestic Tags

• Smart packages program microwave for cooking– ID only; up-to-date instructions over internet

Michael Hawley’s PIA Group circa 1995

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Tag-Based Pill Monitor

• Paul Yarin, Rich Fletcher, Becton-Dickenson• Circa 1998?

Presto Technologies

Board of Directors Dr. Andrew Lippman, Founder & Chairman

Associate Director, MIT Media Lab and Director, Digital Life Consortium

Henry Holtzman, Founder & CEODr. Michael Hawley, Founder

Director, Things that Think and Toys of Tomorrow consortia, MIT Media Lab

Ronald Chwang, AdvisorPresident, Acer Ventures

ManagementHenry Holtzman, Chief Executive OfficerPatricia Robertson, VP, Marketing & Business Development

“One Wave” E-Commerce Infrastructure

Infrastructure for Digital Identification

• The PrestoPad– Based mouse pad with embedded

Swatch Access tag reader designed at the Media Lab (late 90’s) for sponsor interaction

– Embedded custom agile tag reader designed by Presto Team.

– Business Plan based around being the main network site connected to tag-embedded products

• Medicine, food, items benefiting from instruction or participation

– Migrated to becoming the agency tied to RFID-embedded customer cards

• Customers benefit from personalized deals and information

The PrestoTagThe PrestoTag, once placed on the PrestoPad, initiates radio frequency communication

PrestoPadAfter reading the PrestoTag’s unique ID, the PrestoPad sends the information to the client

The Presto DriverThe Presto Driver software takes the PrestoTag information and communicates with the Presto Server

The Presto ServerThe Presto Server is the backbone of Presto’s service platform. At its most basic, the Presto Server maps each PrestoTag’s identifying information to targeted response information. The result can be the launch of a merchant’s personalized web page, an online radio station, or the initiation of an e-commerce transaction.

The Presto Platform

First low-cost tag reader ($10./unit for >10K pieces), probably first USBMulti protocol RW (Phillips HiTag, EM-Marin) 125 kHz

How it works:Easy Online Buying

“One wave” convenience at multiple destinations -- without the need for passwords, PINs, or user name.

… when finished shopping, simply proceed to checkout….

Customers shop at their favorite sites, adding items to their shopping cart...

… accurately provides shipping, billing, credit card information ready for verification and checkout.

...“one wave” of the branded credit card over their PrestoPad…

How it works:Personalized Merchant Promotions

… instant order execution with “one wave”...

… purchase decisions are instantly initiated because the user is already authenticated ...

…is instantly taken to personalizedmerchant account –no typing required ...

Customer wavesmerchant affinity card over PrestoPad …

Shipping, billing, credit information is provided through Presto Server to merchant.

Flexible form factors: key tags, branded product icons.

No URLs, names, PINs, or passwords.

Personalized merchant affinity programs are seamlessly linked to Presto payment mechanisms.

“One Wave” E-Commerce Infrastructure

Presto raised $4M between its inception in 1998 and demise in October of 2001Perhaps too early, ignored security issues, affected by post-911-slump

http://www.tagsense.com/

About TagSense, Inc.

• Founded March 2000• MIT engineers• 1200 ft lab/office space

Technology innovation:• Custom tag design

(chipless/chip)• RFID sensors, security• Custom reader design

Sample Clients:• US Postal Service, MasterCard,

NASA, Kaiser-Permanente, Proctor & Gamble, …

info@tagsense.com

Rich Fletcher

IC Tags:• silicon IC• polymer IC

RFID Technologies

Sensor Tags:• chip• chipless

Chipless Tags:• magnetics• LC• other

Chipless Tag: What is It?

WAVEFORMDETECTION

FEATUREEXTRACTION

FEATUREDECODING

S

f , t

“analog information”

DIGITAL CODE

• No chip required – ID is stored in the analog spectrum!• US Patents: 6472987, 6693540, 6724310

Fletcher, PhD, 2000

EXAMPLE: Navigation for the Blind

Clip-on Cane RFID Reader unit

RFID Tags Embedded in Floor Markers

• Audio Feedback• Stores up to 1 GBAudio WAV files

RFID Tag can also be a Sensor!

• Materials response can be used to detect local environment

• Wireless monitoring of:– Pressure– Humidity– Temperature (continuous and

threshold)– pH

• US Patents:6025725, 6208253

CL

PVDF

F

EXAMPLE: NASA Space Shuttle Project (SBIR)

EMBEDDED SENSORS

RFID READER IN MOBILE ROBOT

Wireless Monitoring of Temperature and Pressure

Cell Phone RFID Readers

• Multi-protocol Reader (EPC, iCode, ISO15693,

ISO14443A/B)• JAVA programmable

• 2-Way RFIDNear-Field Communications

(NFC Protocol)

• Applications:– Mobile Payment

(MasterCard PayPass)– Access Control

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ThingMagic

• Founded in 2000 by students from the Physics & Media Group• Profitable – becoming increasingly focused on tag reader products• Work with MIT AutoID Center and several corporate clients

– Wallmart, Sensormatic, others… http://www.thingmagic.com

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Mercury Universal Readers