Variable frequency vibratory alert method and structure

摘要

A portable vibratory alerting device (20) is part of a resonant system (20, 30) and has a resonant vibrator (60) for both generating a vibrational alert and sensing the resonant frequency of the resonant system. The vibrator (60) is driven by a variable frequency driver (76, 78), and thereafter the resonant frequency is measured by a sensor (82). A vibration controller (72) causes the frequency of the vibrator to be substantially equal to the resonant frequency of the system.P PAlternately, a portable alerting device (520) has both a vibrator (160) and a sensor (166) for sensing the amplitude of a vibratory alert at various frequencies. A vibration controller (72) generates a vibratory alert at an optimum frequency in response to the sensed amplitudes.