Hi everyone!
My name is Adrian Catana, and I'm a PhD Student at Stefan cel Mare University of Suceava.
Today, I want to share with you our work titled "Fingerhints: Understanding Users' Perceptions
of and Preferences for On-Finger Kinesthetic Notifications."
Notifications are ubiquitous in our lives.
Daily, we receive an impressive number of notifications, whether we are talking about
a text message, a calendar event, or even a reaction on social networks.
Introducing "Fingerhints," our mathematical formalization of peripheral kinesthetic feedback
delivered at finger level.
Three dimensions compose what we call a "fingerhint."
Dimension one consists of the primary movement of the finger, flexion, and extension, noted
with theta.
Abduction and adduction are the second dimension, notated with phi.
The last dimension is dwell time and represents duration while the finger is kept in one specific
pose at a given joint.
Using the shown formalism, we define on-finger kinesthetic notifications as movements that
put the finger into a series of n poses at joints j.
We conducted a controlled experiment to measure the user perception of fingerhints as well
as to elicit preferences for suitable fingerhints.
To be able to do this, we developed a finger-augmentation device that can execute controlled finger
hyper-extensions.
The device consists of a 3D-printed PLA platform, fastened with Velcro strips to the hand.
On the platform, we mounted a servomechanism with a torque of up to 3.3kg/cm at 4.8V.
A controlled experiment was conducted in order to measure the user perception of fingerhints
delivered by our custom-made finger-augmentation device.
Furthermore, the aim was to elicit preferences for suitable fingerhints corresponding to
common notification types on mobile devices.
In the first step, participants had to fill in the first questionnaire about their use
of mobile and wearable devices and general attitudes towards notifications, followed
by personality, creativity, and index-finger dexterity tests.
Next, we place the device on participants' dominant hand then ran a prerecorded, 3-minute-long
sequence of fingerhints to demonstrate various extension angles and dwell times.
To enable the participants to experience fingerhints in a diversity of situations involving the
wearing hand, we replayed the sequence of finger extensions in the following conditions:
hand on table, hand alongside the body, hands holding the smartphone, hands holding a large
box, resting the head in the hand, shake hands.
The order of these conditions was randomized per participant.
After each condition, we administered a short questionnaire with a mixture of user experience
measures.
Once the participants had formed an understanding of the capabilities of our finger-augmentation
device, we asked them to think about suitable fingerhints for several notification categories.
We instructed the participants to propose fingerhints they thought were intuitive, comfortable,
and memorable.
In the final part of the experiment, participants filled out a questionnaire containing measures
about the overall perceived usability, social acceptability, and wearable comfort of fingerhints.
The Johnson's personality traits show some interesting correlations.
Data analysis revealed that high usability ratings were provided by participants with
extroversion traits.
Finger dexterity was evaluated with a measure from NEPSY battery.
We found that the participants with higher finger dexterity rated higher the goodness
of their fingerhints, while participants that could extend their index finger more, leveraged
this dexterity ad-vantage to propose fingerhints with larger extent.
We found a significant negative relationship between creativity and extent.
More creative individuals preferred fingerhints with smaller extensions of the index finger.
Perceived so-cial acceptability was higher when alone or with family.
Our participants considered notifications important, useful, yet somewhat disruptive.
We found that participants who felt more in control of when and how they received notifications
provided higher usability ratings.
At the same time, participants who rated higher the perceived disruptiveness of mobile notifications,
also rated higher the implied malice dimension of fingerhints.
We measured usability with SUS and UMUX ratings.
The mean SUS score was 67.4, repre-senting marginally acceptable usability close to "good,"
according to Bangor et al.'s acceptability ranges and adjective ratings for interpreting
SUS scores.
We evaluated fingerhints with the Perceived Creepiness of Technology Scale, a tool for
measuring how creepy a new technology appears to users in an initial encounter.
Perceived creepiness varied between 9.3 and 50.9, revealing a large range of first impressions
with a significant difference among the subscales.
In the third step, we elicited preferences for fingerhints in response to the conditions
of the Notification-Type independent variable.
After analyzing the data, we found very low agreement rates, which indicate different
user preferences for fingerhints.
Having established devices directly comparable to Fingerhinter, we designed an experiment
to collect perceptions of our device in the context of its peers.
We used four commercially available finger- and hand-augmentation devices.
The participants wore each device during two activities: manipulation of a small objects
and large objects.
After each combination of Device and Activity, they filled out a questionnaire about wearable
comfort and perceived creepiness.
To complement the findings of our in-lab experiments, we conducted a supplementary study in the
wild.
We recruited a new participant, let's call him James, 25 years old, male, which we asked
to wear our Fingerhinter for eight hours continuously while carrying out his usual daily activities.
Regarding the social acceptability of Fingerhinter, James reported having noticed reactions from
curious people in public areas, such as in the restaurant when "everyone was looking
at the device."
Overall, James' experience of prolonged use of fingerhints was mixed, primarily because
Fingerhinter was not meant for deployment in real life.
Thank you for watching.
For more details, please see our paper.