title: Effects of grip force on skin conductance measured from a handheld device.
abstract: Skin conductance (SC) reflects stimulus significance and can be measured by integrating electrodes directly onto a smartphone housing such that they are naturally contacted when gripped. However, grip artifacts naturally arise during operation since grip forces can vary. We explored the effects of grip force on SC to determine feasibility and to draw guidelines on artifact mitigation. For this purpose, a prototype was built with integrated SC electrodes with colocated force sensors, and data was collected from 24 participants gripping the prototype across different grip force conditions. Our analysis showed that static forces greater than 2.0 N were associated with significant SC distortion, and artifacts induced from dynamic grip forces were buffered if the SC level was at least 1.1 microsiemens. Our findings are relevant for future applications of SC sensing on smartphones, which may enable interesting and highly contextual user experiences.
authors.affiliation: Qualcomm Research, San Diego, California, USA.
authors.forename: Robert
authors.initials: R
authors.lastname: Tartz
authors.forename: Aniket
authors.initials: A
authors.lastname: Vartak
authors.forename: Jay
authors.initials: J
authors.lastname: King
authors.forename: Don
authors.initials: D
authors.lastname: Fowles
mesh_terms: D000293:Adolescent; D000328:Adult; D034201:Computers, Handheld; D004566:Electrodes; D005240:Feasibility Studies; D005260:Female; D005712:Galvanic Skin Response / Q000502:physiology*; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018670:Monitoring, Ambulatory / Q000295:instrumentation*; D000068997:Smartphone; D055815:Young Adult
keywords: EDA; EDR; Electrodermal activity; Electrodermal response; GSR; Galvanic skin response; Grip force; Mobile devices; Skin conductance; Smartphones