A Thin Stretchable Interface for Tangential Force Measurement (UIST 2012)
1. A Thin Stretchable Interface
for Tangential Force Measurement
Keio University1 / The University of Tokyo2
JST ERATO IGARASHI Design Interface Project3
Yuta Sugiura1,3, Masahiko Inami1,3 and Takeo Igarashi2,3
2. Interaction with Skin
• People have long made use of their skin to
communicate intentions and emotions to each
other via touching.
3. Skin-like Interface
• Our interface is
– thin, stretchable, simple configuration and provide
natural haptic feedback like a skin.
• It gives the ability of skin to daily objects
externally.
Smart phone
Home appliance
Furniture Robot
5. Using this, we can...
• Enable more natural communication with
computer systems.
– Adding skin for robots
– New game controller
– Sensing body movement
6. Highlights
1) Measurement of stretch of thin
materials using photoreflectors
2) Packaged small sensor module
3) Multi-sensor system that
determines the tangential forces
4) Example applications
7. Highlights
1) Measurement of stretch of thin
materials using photoreflectors
2) Packaged small sensor module
3) Multi-sensor system that
determines the tangential forces
4) Example applications
8. Components of the Interface
• Thin stretchable material such as stocking
• Using photoreflector that consist of
– Infra-red LED
– Phototransistor
Phototransistor
Infra-red LED
PhotoreflectorStocking
9. Photoreflector Stocking
Emitted Light
Reflected Light
Normal condition Material is stretched
Measuring Stretch of Stocking
Transmissivity
Light
• Emitted light pass through the material
when the material is stretched.
11. Comparison of Sensing Methods
• Strain gauge
– The soft properties is changed.
• Image based sensing [Soap, Baudish 2007]
– Measuring the material’s relative translational
displacement
• Photoreflector (Our approach)
– Measuring the density of material
– Thin
– Low-cost and easily fabrication
12. Measurement Experiment
• 20 denier stocking
• Pull the stocking by 2mm each time
• Release the stocking
• Measuring 30 times to check the hysteresis
Digital Force GaugePhotoreflector
Stocking
13. Highlights
1) Measurement of stretch of thin
materials using photoreflectors
2) Packaged small sensor module
3) Multi-sensor system that
determines the tangential forces
4) Example applications
14. Small Sensor Module
• One photoreflector
• Battery and
Microcontroller are
embedded.
• Coin size
• Wireless
Li-Po Battery (50mA)
Battery
Connector
Photoreflector
Microcontroller
Bluetooth
15. Highlights
1) Measurement of stretch of thin
materials using photoreflectors
2) Packaged small sensor module
3) Multi-sensor system that
determines the tangential forces
4) Example applications
16. Multi-sensor System that
Determines the Tangential Forces
Tangential force
Pinch-in
Pinch-out
• Multiple photoreflectors are placed under the
material.
17. Combination with Conventional
Pressure Sensors
• Detecting normal force and tangential
forces
On pressure sensor array On FuwaFuwa sensor
[Sugiura 2011]
18. Highlights
1) Measurement of stretch of thin
materials using photoreflectors
2) Packaged small sensor module
3) Multi-sensor system that
determines the tangential forces
4) Example applications
19. Smart Phone – Flat Type
• Normal touch (Capacitive sense) → Location of object
• Pressure (Skin Interface) → Rotation of object
20. Smart Phone – Curved Type
• Curved type supports pinching dragging, and
releasing gestures.
24. Other Possible Applications
• As a chair cloth
– Detecting the posture of sitting,
especially slipping
• Sensing muscle movement and
edema
– Continuous human body monitoring
25. Limitations
• Affected by ambient light such as
sunlight.
• Affected by the user’s hand or
other object.
• Durability of thin material
26. Related Research
Sheer Gesture,
[Harrison 2012]
Robot Skin,
[Ohmura 2006]
Force Gesture,
[Heo 2011]
Khronos Projector,
[Cassinelli 2005]
GelForce,
[Kamiyama 2006]
rSkin,
[Perner-Wilson 2010]
27. Conclusion: Enabling Skin-like
Properties in Daily Objects
• Our interface is
– thin, stretchable, simple configuration and
provide natural haptic feedback like a skin.
• Highlights
1) Measurement of stretch of thin materials
using photoreflectors
2) Packaged sensor module
3) Multi-sensor system that determines the
tangential forces
4) Example applications
yuta.sugiura@gmail.com, http://sugiur.com