Anisotropies of touch in haptic icon exploration

Handheld devices are enhancing many aspects of our lives. As increasingly complex devices appear with decreasing form factors, haptics may become an essential tool for interacting with them. In this regime of operation, issues of power, weight and volume are of significant importance. The haptic thresholds of the index finger for active exploration of a two dimensional virtual environment for two icon alignments and two finger motions were measured. Using all possible combinations of two finger motions, flexion/extension and finger abduction/adduction, and two icon alignments, vertical and horizontal, were measured separately. Haptic thresholds ranged from 15 to 24 milliNewtons. Thresholds were affected by finger motion, but not by icon alignment.