Optimization of the envelope of a short duty cycle pulse waveform for tactile stimulation

Presents a study to optimize the power delivered by an excitatory waveform to the frequency region of maximum vibrotactile sensitivity (25-700 Hz). The study optimizes the ratio between the power delivered by the waveform within the region of maximum tactile sensitivity, Q_fw and the total power delivered by the waveform in one cycle, P_T. The excitatory waveform is composed by a burst of short duty cycle rectangular pulses with an envelope modulating the pulse amplitudes, followed by a recovery time. The study enables, for each pulse frequency, to select an optimum pulse width and an optimum envelope for the rectangular pulses that reduces the total power delivered by the waveform while maintaining the same amount of power within the region 25-700 Hz. Results show that by using an optimum envelope and pulse width, the ratio, Q_fw/P_T, can be improved nearly 17% at a pulse frequency of 250 Hz and 1,632% at a pulse frequency of 120 Hz, when compared to a 50% duty cycle and rectangular envelope waveform