Understanding How Epidermal Devices Affect Human Tactile Perception
The emerging class of epidermal devices opens up new opportunities
for skin-based sensing, computing, and interaction.
Future design of these devices requires an understanding
of how skin-worn devices affect the natural tactile perception.
In this study, we approach this research challenge by
proposing a novel classification system for epidermal devices
based on flexural rigidity and by testing advanced adhesive
materials, including tattoo paper and thin films of
poly (dimethylsiloxane) (PDMS). We report on the results
of three psychophysical experiments that investigated the
effect of epidermal devices of different rigidity on passive
and active tactile perception.We analyzed human tactile sensitivity
thresholds, two-point discrimination thresholds, and
roughness discrimination abilities on three different body
locations (fingertip, hand, forearm). Generally, a correlation
was found between device rigidity and tactile sensitivity
thresholds as well as roughness discrimination ability. Surprisingly,
thin epidermal devices based on PDMS with a
hundred times the rigidity of commonly used tattoo paper
resulted in comparable levels of tactile acuity. The material
offers the benefit of increased robustness against wear and
the option to re-use the device. Based on our findings, we
derive design recommendations for epidermal devices that
combine tactile perception with device robustness.
The publication received a Best Paper Honorable Mention Award at ACM CHI’19.