Investigating the

ofwrist-based input

TILT TECHNIQUES

DEXTERITY

mahfuz rahmansean gustafsonpourang irani sriram subramanian

TILT-BASED INTERACTION

CONTRIBUTIONSframework for tilt-based interaction

capabilities of each wrist axis

comparison of methods for discretizing the raw tilt sensor readings

RELATED WORK

[Rekimoto UIST96]

[Hinkley UIST00]

TiltType [Partridge UIST02]

TiltText [Wigdor UIST03]

[Crossan MobileHCI08]

FRAMEWORK

1. Axes of wrist movement

2. Rate control vs. position control

3. Discretization of raw tilt values

4. Selection mechanism

5. Feedback

1. AXES OF MOVEMENT

Flexion / Extension

1. AXES OF MOVEMENT

Pronation / Supination

65°

Ulnar / Radial Deviation

1. AXES OF MOVEMENT

2. RATE VS. POSITION

We use position control

3. DISCRETIZATION

Linear

Quadratic Sigmoid

y=1/(1+e-x) y=x2

4. SELECTION MECHANISM

click-tilt-release

click-to-select

5. FEEDBACK

visual – remote or local

auditory

tactile

EXPERIMENT

TASK

INDEPENDENT VARIABLEStilt axis: flexion/extension, pronation/supination, ulnar/radial deviation

discretization function: linear, sigmoid, quadratic

divisions: 4, 8, 12, 16. Only 4 divisions for deviation

distance: 10%, 30%, 70%, 90% of range of motion

direction: 0° to max, max to 0°

DEPENDENT VARIABLES

completion time

error rate

number of crossings

FLEXION RESULTS

05

101520253035

0 4 8 12 16

% E

rror

s

Levels

0

1000

2000

3000

0 4 8 12 16

Tim

e (m

s)

Levels

LinearSigmoidQuadratic

PRONATION RESULTS

05

101520253035

0 4 8 12 16

% E

rror

s

Levels

LinearSigmoidQuadratic

0

1000

2000

3000

0 4 8 12 16

Tim

e (m

s)

Levels

DEVIATION RESULTSonly with 4 levels

05

101520253035

Linear Sigmoid Quadratic

% E

rror

s

0

1000

2000

3000

Linear Sigmoid Quadratic

Tim

e (m

s)

EXPERIMENT 2

Design same as experiment 1 except

Remote feedback

No sigmoid function

DISCUSSION

IMPLICATIONSFOR DESIGN

DESIGN GUIDELINES

avoid ulnar/radial deviation if possible or use only for input of a couple levels.

flexion/extension is limited to 8 levels of tilt

pronation/supination is limited to 12 levels of tilt

discretization function plays an important role

TILT TEXT

[Wigdor UIST03]

CONCLUSION

a framework for tilt-based interaction

characterization capabilities of each wrist axis

comparison of methods for discretizing the raw tilt sensor readings

THANKS!Sean GustafsonHasso Plattner Institute

http://www.seangustafson.com