Comparing feasibility of a Haptic headband vs waistband during navigation where vision may have been compromised . Done in collaboration with NASA.

1. Wearable Haptics for Directing
Comparing the feasibility of the Head Mounted tactile display with the
Waist Mounted tactile display
Apurva Gupta, Shashank Jagirdar, Manasvi Lalwani, Thad Starner, Clint Zeagler

2. BACKGROUND RESEARCH
Van Erp et. al [1] demonstrated that tactile feedback on the torso
immediately leads to a percept of external direction. This effect is
called ‘tap-on-the-shoulder’ effect, and is akin to a person’s reflex
action to look in the direction they have been tapped on their
shoulder.
We hypothesized that a similar effect could be produced on the
head, since it has similar affordances.
Further research revealed that while a lot of work has been done in
exploring Torso-mounted tactile displays and Head-mounted
displays, there was a gap in literature comparing the two.
1. Van Erp, J.B.F. (2001). Tactile navigation display. In: S. Brewster, R.
Murray_Smith(Eds.): Haptic Human Computer Interaction. Lecture notes
in computer science Vol.2058, pp. 165-173. Berlin Heidelberg: Springer
Verlag.
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3. DESIGN
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4. 1. The forehead, occipital, and temple regions of the
head are most sensitive to vibration
stimulation. Therefore, these regions should be
considered for purposes related to head
tactile communication.
2. A four-tactor, circular head array is recommended for
an HMTD design (alongside).
3. The vertex (CZ) and the temples (T3, T4) are head
locations that are most suitable for BC
vibrator placement. The temples (T3, T4) are also
suitable head locations for vibration
stimulation or head tactile communication.
Myles, K., & Kalb, J. T. (2010). Guidelines for head tactile communication (No. ARL-TR-5116). ARMY
RESEARCH LAB ABERDEEN PROVING GROUND MD HUMAN RESEARCH AND ENGINEERING
DIRECTORATE.
GUIDELINES FOR HEAD TACTILE DISPLAY
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5. 4-tactor display design
Abdomen-mounted tactile display belt
Head-mounted tactile display belt
Conveys point-to-point information:
Right motor buzzing indicates- Turn Right
Left motor buzzing indicates- Turn Left
Front motor buzzing indicates- Move forward
Back motor buzzing indicates- Move Backward
Vibration Motors
Velcro
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6. Feasibility Study
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7. Keyboard
Simulation
Band/Belt
Arduino
Within Subject design with 10 participants
where they navigate through a simulation
based on feedback provided by the
band/belt by pressing arrow keys on the
keyboard.
Measures- Completion Time, Comfort,
User Preference
Experiment 1
Schematic of the Experiment 1
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8. Magnetometer
+ Bluetooth
Band/Belt
Arduino
Within Subject design with 5 participants where
the tactors orient the n in a particular direction
form the starting point. The participants had
their eyes shut.
Measures - Completion Time, Comfort, User
Preference
Experiment 2
Schematic of the Experiment 2
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9. Participants asked to orient themselves(with eyes shut) based on feedback from the band.
Demo Video: https://vimeo.com/125433621
Magnetometer
mounted to sense
Current Orientation
Experiment 2
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10. Results
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11. • There was no difference in understanding the stimulus from either of the bands though head band
had a slightly higher rating while using the stimulus in the task (Head: M = 4.2, SD= 0.7; Waist:
M=3.8, SD=0.6)
• All the participants found Waist belt more comfortable and subtle in response.
• 60% participants found Headband to be better for clear feedback whereas 40% of them found it
annoying.
• Some participants suggested to use pulses rather than continuous buzzes since over a period of
time they seemed to get numb to the vibrations
Experiment 1
Average Response Time (Waist Belt) Average Response Time (Head Band)
154.21 ms 140ms
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12. USER PREFERENCE
Those who preferred Head:
•Preferred wearing Head gear
•Deemed performance important than comfort
•Indicate the stomach area to be more private
for such interactions
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13. 5 participants took part in the study, all of whom were Male with an average age of 22.6 years
Comfort Ratings (Head: M = 4.8, SD= 0.4; Waist: M=4.4, SD=0.489 )
ALL the participants reported that they found the headband better to navigate but found the waistband more
comfortable.
Other user insights:
Some users reported that they felt the feedback felt “natural” and even “reflexive”
Experiment 2
5 participants performed the task for 4 different orientations(45, 90, 135, 270)
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Mean N Std. Deviation
Pair 1 HeadTimes
WaistTimes
4.8595
7.3970
20
20
1.583
4.198

14. Head vs Waist Plots for Experiment 2
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15. Conclusion
• Waist band was found to be more comfortable than Headband
• Head band was found to be more prompt than Waistband
• User preference was based on the dimension of:
• Comfort
• Performance
• Suggestion were made to have different vibration pulses rather
than a continuous stream.
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