A Shoulder Pad Insert Vibrotactile Display

Aaron ToneyBruce H. Thomas

Wearable Computer Laboratory

University of South Australia

Lucy DunneSusan P. Ashdown

Department of Textiles and Apparel

Cornell University

ISWC 2003

Our Goals for Today’s Mass-Market Wearable Devices

1. Maintain consumer’s current relationship with garments (physical, psychological, and social)

2. Minimize impact of devices on user social interactions (minimize social weight)

Wearable Integration

• Embedding technology within the current structure of clothing imposes restrictions on:– Size– Weight– Form factor– User interface options

Our Solution: Standard Clothing Inserts

What are Standard Clothing Inserts?

• Layers of padding, interfacing, or other materials meant to give shape, strength, or protective function to the garment.

• Location and function of clothing inserts vary with age, gender, season, garment function, and current fashions.

• Inserts are a fundamental part of the clothing structure, not pockets which are added to the surface.

Standard Clothing Inserts

Standard Clothing Inserts

• Exist in many common garments• Maintain physical and

psychological expectations and user relationships between wearer and garment

• Minimize outward appearance of electronics, diminishing social impact of augmented garments

But I Don’t Wear Shoulder Pads Anymore!

Goals of this Research

• Examine the utility of clothing inserts as a housing space for electronic components.

• Evaluate the potential of shoulder worn vibrotactile displays

Why a Tactile Shoulder Pad?

• Proximity of clothing to the body provides optimal opportunity for integration of tactile displays

• Shoulder area is a culturally habitual area for receiving tactile stimuli

• Shoulder pad provides a pre-existing volume in which to embed electronics.

• Shoulder pad is a part of the business suit, one of the most standardized garment systems in our culture.

Some Applications for a Tactile Shoulder Display

• Navigation for both fully-sighted and seeing-impaired individuals

• Silent alerts• Socially subtle transmission of

information• Motion guidance for physical

activities

Development of a Shoulder Pad Insert Vibrotactile Display

Fitting the Population

• Army ANSUR database of anthropometric measures

• 3,982 subjects: 2,208 female

• US Army population

ANSUR Measures Used

A: Shoulder Length, B: Cervicale Height, C: Axilla Height, D: Acromial Height

Derived Body Size Specifications

SIZE LENGTH HEIGHT CURVE 1 13cm 5cm 22cm 2 15cm 7cm 24cm 3 17cm 9cm 26cm

Body Size

SIZE LENGTH HEIGHT CURVE 1 11cm 3cm 20cm 2 13cm 4cm 22cm 3 15cm 5cm 24cm

Pad Size

Fabrication of Shoulder Pad

• Conflicting goals– Stability and structure– Isolation of individual vibration areas

• Compromise: a layered prototype

Fabrication of Shoulder Pad: Final Prototype

Pad closure, outside edge Pad interior, showing layers and motor attachment (4-motor

configuration)

Integration of Vibrotactile Shoulder Pad into Test

Jackets

Fabrication of Shoulder Pad: Prototype Configurations

Motor locations for right shoulder: 4- and 6- motor configurations pictured against the

shoulder

Experimental Subjects

• 12 subjects, all female• Ages 19-34• Varied body types and sizes• Shoulder lengths 9 - 14.5cm

Experimental Procedure: Subjects

4 -m o torco n fig u ra tion

6 -m o torco n fig u ra tion

In fo rm ed

4 -m o torco n fig u ra tion

6 -m o torco n fig u ra tion

U n in fo rm ed

Experimental Procedure: Trials

• Tested dominant side • Motor activation:

– individuals, pairs, threes, fours, fives, and sixes, randomly generated combinations

– total 15 trials for 4-motor configuration, 24 trials for 6-motor configuration

• Subjects responded on generic torso figure (open response)

Experimental Procedure: Subject Responses

Experimental Procedure: Qualitative Questionnaire

• Following pad testing, subjects completed a questionnaire concerning:– comfort of the electronic shoulder pad

vs. standard shoulder pad– comfort of vibrational sensation– mental difficulty in determining location

of stimulus

Results: Mapping Stimuli

Composite subject responses: responses often covered a much larger area than the actual

shoulder pad.

Results: Comfort

• All subjects found the electronic shoulder pads at least as comfortable as the standard shoulder pads

• Subject responses to the vibration stimulus varied from soothing or comforting (3 subjects) to annoying or ticklish (3 subjects), but most subjects found the stimulus neither annoying nor comfortable

Results: Cognitive Load

• Generally high concentration level– Qualitative responses– Observational data

• Reflected in accuracy of responses• Stimuli appeared less difficult to

localize in 4-motor configuration

Results: Perception of Motors

• Each subject experienced at least one motor location that could not be felt.

• Subject perceptions generally consistent throughout trials

• Motor coupling effects extended the perceived activation area

Example of a Missed Motor for One Subject

Trial 1

Trial 2

• Red=actual activated motors

• Shading=subject response

• Lower front motor missed in both trials

Results: Missed Motors

• Body locations of consistently missed motors are not consistent between the 4-motor and 6-motor configuration.

Missed Motors:

Miss frequency for each motor location

• The neck-edge motor was missed in both configurations.

Neck NeckShoulder Shoulder

Conclusions

• Shoulder worn displays show promise for wearable multi-bit wide displays.

• Garment inserts provide a viable space to house electronic components for wearable devices.

• Each subject felt at least one combination of motors.

• Distinct perceptibility of individual motors or patterns varied considerably between subjects.

• Individual subjects’ perceptions were consistent throughout testing.

Future Work

• Further experimentation to determine consistent perceptibility

• Wireless shoulder pad unit• Testing of moving tactile patterns• Use of shoulder pad to transmit

information• Involve in a physiologist for further

multidisciplinary insights

Future Work

Come See our Demo!

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