Perceived Urgency Scaling in Tactile Alerts

Abstract

Tactile vibrations are potentially useful in a variety of environments to communicate information to visually and auditorily overloaded people. However, since vibrotactile signals must come into physical contact with the skin, they may also be perceived as highly urgent and annoying. The current study examined whether scalable levels of perceived urgency could be obtained with tactile signals by measuring the relationship between changes in vibrotactile pulse rate and ratings of urgency and annoyance. In two separate experiments, changes in pulse rate resulted in changes in ratings of perceived urgency with faster pulse rates being perceived as more urgent. Importantly, in both studies pulse rate had a greater impact on perceived urgency than it did on annoyance suggesting that scalable levels of urgency can be achieved without similarly annoying operators. Results are discussed in terms of their implications for multimodal display design.