HaptiDrag: A Device with the Ability to Generate Varying Levels of Drag (Friction) Effects on Real Surfaces.

We presently rely on mechanical approaches to leverage drag (friction) effects for digital interaction as haptic feedback over real surfaces. Unfortunately, due to their mechanical nature, such methods are inconvenient, difficult to scale, and include object deployment issues. Accordingly, we present HaptiDrag, a thin (1 mm) and lightweight (2 gram) device that can reliably produce various intensities of on-surface drag effects through electroadhesion phenomenon. We first performed design evaluation to determine minimal size (5 cm x 5 cm) of HaptiDrag to enable drag effect. Further, with reference to eight distinct surfaces, we present technical performance of 2 sizes of HaptiDrag in real environment conditions. Later, we conducted two user studies; the first to discover absolute detection threshold friction spots of varying intensities common to all surfaces under test and the second to validate the absolute detection threshold points for noticeability with all sizes of HaptiDrag. Finally, we demonstrate device's utility in different scenarios.