Title: Ramesh Raskar, Paul Beardsley, Jeroen van Baar, Yao Wang, Paul Dietz, Johnny Lee, Darren Leigh, Thomas Willwacher
1R F I G Lamps Interacting with a
Self-describing World via Photosensing Wireless
Tags and Projectors
- Ramesh Raskar, Paul Beardsley, Jeroen van Baar,
Yao Wang, Paul Dietz, Johnny Lee, Darren Leigh,
Thomas Willwacher - Mitsubishi Electric Research Labs (MERL),
Cambridge, MA
2Radio Frequency Identification Tags (RFID)
No batteries, Small size, Cost few cents
Antenna
microchip
3Warehousing
Routing
Livestock tracking
Library
Baggage handling
Currency
4Conventional Passive RFID
5Tagged Books in a Library
- Id
- List of books in RF range
- No Precise Location Data
- Are books in sorted order ?
- Which book is upside down ?
6Where are boxes with Products close to Expiry
Date ?
7Conventional RF tag
Photo-sensing RF tag
8Photosensor ? Compatible with RFID size and power
needs
Projector ? Directional transfer,AR with Image
overlay
9b. Tags respond with date and precise (x,y) pixel
location, Projector beams Ok at that location
a. Photosensing RFID tagsare queried via RF
c. Multiple users can simultaneously work from a
distance without RF collision
10(No Transcript)
11RFID(Radio Frequency Identification)
RFIG(Radio Frequency Id and Geometry)
12Prototype Tag
RF tag photosensor
13Outline
- Photosensing RF tags
- Location sensing
- Geometric Operations
- Multi-view analysis
- Deformation
- Interactive Projection
- Mouse-like interaction
- Image stabilization
14Outline
- Photosensing RF tags
- Location sensing
- Geometric Operations
- Multi-view analysis
- Deformation
- Interactive Projection
- Mouse-like interaction
- Image stabilization
- Applications
15Projected Sequential Frames
PatternMSB
PatternMSB-1
PatternLSB
- Handheld Projector beams binary coded stripes
- Tags decode temporal code
16Projected Sequential Frames
PatternMSB
PatternMSB-1
PatternLSB
- Handheld Projector beams binary coded stripes
- Tags decode temporal code
17Projected Sequential Frames
PatternMSB
PatternMSB-1
PatternLSB
- Handheld Projector beams binary coded stripes
- Tags decode temporal code
18Projected Sequential Frames
PatternMSB
PatternMSB-1
PatternLSB
- Handheld Projector beams binary coded stripes
- Tags decode temporal code
19Projected Sequential Frames
PatternMSB
PatternMSB-1
PatternLSB
- Handheld Projector beams binary coded stripes
- Tags decode temporal code
20PatternMSB
PatternMSB-1
PatternLSB
0
1
1
0
0
X12
- For each tag
- From light sequence, decode x and y coordinate
- Transmit back to RF reader (Id, x, y)
21Visual feedback of 2D position
- Receive via RF (x1,y1), (x2,y2), pixels
- Illuminate those positions
22Limitations
- Line of sight
- Surface patches
- Multiple tags per object
- Ambient light
- Modulated infrared
- Surface reflectance and shadows
23Outline
- Photosensing RF tags
- Location sensing
- Geometric Operations
- Multi-view analysis
- Deformation
- Interactive Projection
- Mouse-like interaction
- Image stabilization
- Applications
24Find 3D coordinates
- Observe structured patterns via Camera
- Triangulate cam/proj view
253D from 2 Projector Views(Structure from Motion)
- Two unknown projector views
- Correspondence is trivial
- Applications
- Detect 3D deformations
- Trajectory grouping
26Change Detection without fixed camera, in any
lighting condition
Before
After
Record coordinates of tags from one view
Compare with new coordinates from a different
view
27Texture Adaptation
28Outline
- Photosensing RF tags
- Location sensing
- Geometric Operations
- Multi-view analysis
- Deformation
- Interactive Projection
- Desktop-like interaction
- Image stabilization
- Applications
29Desktop-like Interaction
Selecting tags
30Support for handheld projection
31Mouse Simulation
- Cursor follows handheld projector motion
- Pre-warped image remains stable
32Image Quasi-Stabilization
Eliminate hand jitter using inertial
sensorscamera
33Absolute Stabilization
Image stays registered with world features
34Image Stabilization
35Interactive Projection
(Also in Emerging Technologies Booth)
36Adaptive Projection
Paste Geometric and Photometric compensation
37Prototype Handheld Projector
38Related Work
- Smart objects
- Smart-its
- FindIT Flashlight (Ma and Paradiso 2002)
- Location sensing
- Multiple readers, large antennas
- Olivetti Active Badge, Xerox PARCtab (Want 1995)
- Interaction and Display
- Augmented Reality
- Projector-based AR, Shaderlamps
- (Raskar 1998, Underkoffler 1999, Pinhanez 2001)
- Handheld projector (Raskar 2003)
39Applications
- Single Tags
- Authoring for AR, Store augmentation display per
object - Multiple tags on objects
- 3D Pose
- Packing and placement strategy
- Robot navigation
- Interaction between tagged objects
- History of geometric interaction
- Orientation mismatch
- Distributed tags
- Deformation
- Interpolated values for temperature sensors
40Acknowledgements
- MERL
- Cliff Forlines
- Joe Marks,
- Dick Waters, Kent Wittenburg
- Vlad Branzoi
- Rebecca Xiong, Debbi van Baar
- Mitsubishi Electric, Japan
- Mamuro Kato,
- Keiichi Shiotani
41Interacting with a Self-Describing World
- Hybrid optical and RF communication
- Photosensing Wireless Tags Projector
illumination - Geometric Analysis
- Location, Selection, Augmentation At a distance
- Interactive Projection
- Desktop like interaction
- Stabilized images
- RFIG Applications beyond logistics
- Identity, Geometry, History, Annotation
www.MERL.com
42R F I
G
R F I D
(Radio Frequency Id Geometry)
Photosensing Wireless Tags
Find tag location using handheld Projector
Interactive stabilized projection
Many geometric ops
43(End of Presentation)
44Towards Passive RFID
- Photosensor
- Most compatible with passive batteryless RFID
- Power near zero power for sensing
- Size Each photocell is tens of micrometer
(smaller than RFID which are about 500
micrometer) - Very low cost, can be built with silicon of RFID
microchip - RFIDPhotosensor can be size of grain of rice
- RFIG tag is visible to projector but not to
humans - Current prototype uses battery because passive
tags are difficult to program - Other possibilities
- Adding a light emitting diode (LED)
- Requires on board power
- Size has to be considerably large
- Size and power requirements are high
45Future Directions
- Sophisticated tags
- Light modulation
- Handheld projector
46Comparison with Bar-codes
- RFID
- Barcodes take up more space
- Long bit sequences
- Multiple tags can be simultaneously read
- Read distance is high
- RFIG
- Multiple barcodes per object is cumbersome
- Difficult to attach sensor (e.g. temperature)
47Locate Tags Precisely using a handheld
scanner/projector
Illuminate tags with binary coded stripes with
projector
- Handheld device
- Eliminates multiple RF readers for triangulation
or large antennas - Projector indicates location of tag
48- Photosensor added to RFID tags
- Hybrid communication via RF and via light
- Solve 3 main issues with conventional RFIDs
- Locate tags precisely
- Select a subset of tags for operation
- Long distance operation without collision
- Applications beyond inventory management
- Warehouse locate objects for specific queries
- Training and maintenance interactive augmented
reality - Surveillance keep trail of object locations
492. Select subset of tags for operation
3. Long distance operation without RF collision
- Technique
- Illuminate subset of tags with flashlight or
projector
- Advantages
- Only tags which are illuminated respond to
queries - No RF collision between multiple tags
- Projector also use as a display to indicate
result of operation
50Futures
- We are used to fixed displays like desktops,
laptops, and static projectors. - Handheld devices with screens have become common
over the last decade but the displays are
small. - Handheld projectors offer a new display modality
with its own characteristics - portable device
size but with a large display. - Add interaction to achieve the world as a
desktop
51Interactive Projection
- Desktop like interaction
- Cursor follows use motion
- Center pixel is the pointer
- Rest of the image is stabilized
- Selection
- Image stabilization
- Absolute camera and inertial sensor
- Relative world markers
- Copy-paste
- Camera captures texture during copy
- Projection after geometric/photometric adaptation