Hello everyone, I am Arpit Bhatia. Today, I will be presenting our paper, “Soma-noti:
Delivering Notifications Through Under-clothing Wearables.”.
This is a work by me and my co-authors, Dhruv Kundu, Suyash
Agrawal, and Varnika Kairon, under the guidance of Prof Aman Parnami, at Weave Lab, IIIT Delhi.
Wrist-worn wearable devices are an ideal choice for delivering haptic notifications
due to their proximity to their wearer’s skin. However, the clothes we wear are also in close
proximity to our skin and provide unique opportunities for wearable interactions.
In this paper, we investigate notification channels in the context of wearables
worn on the underside of clothing. Wearing a device in such a way enables it to be in
direct contact with the wearer’s skin which we leverage to deliver haptic notifications. We
refer to wearables in this form factor as badges due to their similarity to the common accessory.
The ten different haptic sensations we evaluated are listed in the current slide. Since tactile
sensitivity varies across body locations and the design of a badge wearable allows it to
be positioned anywhere where there is clothing, we were interested in how the effectiveness of
each channel varies with body location. The six locations that were chosen are meant to encompass
the most common areas covered by clothing. Our hardware prototypes consist of two components:
A set of ten badges corresponding to each sensation and a fanny pack containing the
microcontroller and power source which acts as our processing unit. For exact implementation details,
please refer to our paper. We evaluated the badges through a 10 x 6 within-subjects user study
using two independent variables, Channel and Body Location. We consider four dependent variables,
Response Time, Error Rate, Comfort, and Urgency. The study had 12 participants
and we ran 5 repetitions for each badge-location pair for a total of 300 trials per participant.
During the study, the participants were instructed to walk along a specific path
while wearing one of the ten badges at one of the six locations while keeping their phone in their
hand with our app open. On feeling a stimulus they had to immediately press a button on the app which
recorded the reaction time. The error rate was calculated based on the number of missed stimuli
while the comfort and urgency rating were collected through a questionnaire.
Through ANOVA, we found that channel had a significant effect on reaction time
while Location did not. Poke was the fastest channel which was significantly different from
all others except Pinch and Vibrate. The slowest channel was Cool
which was followed by Heat. This is not surprising given that these
channels have a gradient of change instead of an immediate difference like the others.
In case of error rates, Location had a significant effect while Channel did not. Collar Bone,
Shoulder, and Upper Arm had the lowest error rates and were not significantly different from
each other. We attribute this difference to the fact that clothing is tighter in these locations
due to gravity. The Lower Back has the highest error rate and it was not significantly different
from the remaining locations on the Stomach and Side of the Torso.
Coming to comfort, both Channel and Location had a significant effect on the comfort ratings. All the
ten channels were rated above average for comfort and Cool had the highest rating with participants
referring to it as “pleasing”. The location with the highest comfort rating was the Upper Arm.
While we had anticipated that comfort and urgency would be inversely proportional to each other,
no such trend was observed in the data. Poke had the highest urgency rating which can be attributed
to its use in human-to-human communication to attract immediate attention. The lowest rating
was for Blow with the participants claiming that it is “very gentle”.
In summary, our work “Soma-noti” has two primary contributions:
introducing under-clothing wearable output through a set of ten badge prototypes that produce
different haptic sensations and evaluating the effectiveness of under-clothing wearable output
by studying the performance of these 10 badges across 6 different body locations. We hope that
the results from our study can help designers understand a larger vocabulary of notification
possibilities and better map different types of notifications to different methods of delivery.
Thank you so much for listening!