Intuitiveness of vibrotactile speed regulation cues

Interpretations of vibrotactile stimulations were compared between two participant groups. In both groups, the task was to evaluate specifically designed tactile stimulations presented to the wrist or chest. Ascending, constant, and descending vibration frequency profiles of the stimuli represented information for three different speed regulation instructions: "accelerate your speed," "keep your speed constant," and "decelerate your speed," respectively. The participants were treated differently so that one of the groups was first taught (i.e., primed) the meanings of the stimuli, whereas the other group was not taught (i.e., unprimed). The results showed that the stimuli were evaluated nearly equally in the primed and the unprimed groups. The best performing stimuli communicated the three intended meanings in the rate of 88% to 100% in the primed group and in the unprimed group in the rate of 71% to 83%. Both groups performed equally in evaluating "keep your speed constant" and "decelerate your speed" information. As the unprimed participants performed similarly to the primed participants, the results suggest that vibrotactile stimulation can be intuitively understood. The results suggest further that carefully designed vibrotactile stimulations could be functional in delivering easy-to-understand feedback on how to regulate the speed of movement, such as in physical exercise and rehabilitation applications.