Have you ever missed a call while moving? : The Optimal Vibration Frequency for Perception in Mobile Environments

The characteristics of mobile phone usage when user is moving are different from those when user is sedentary or working in an office (Baek et al., 2006). This means that the default vibration frequency of current mobile phones may not be suitable for use in a mobile environment. Therefore, this study was designed to investigate the optimal vibration frequency for the perception of mobile phone vibration when the user is moving. To guarantee the validity of this study, subjects were asked to indicate their perception of the randomly given 10 vibrotactile stimuli while they performed routine activities on a sidewalk, subway, or bus for about 2 h. The results showed that the optimal vibration frequency in the dynamic state was 190 Hz, considerably higher than 151 Hz the optimal vibration frequency obtained in the static state in the previous study. As a result, mobile phone manufacturers should consider this factor when designing the vibration frequency for the vibration mode so that missed calls in mobile environments are minimized. Key-Words: Mobile environments, mobile phone, perception, optimal vibration frequency, missed call, field study