Electrotactile Stimulation Waveform Modulation Based On A Customized Portable Stimulator: A Pilot Study

Artificial tactile sensation (ATS) is of great importance in diverse fields, especially for amputees to explore and interact with the world. Although prosthesis are dexterous nowadays, lack of tactile sensation is expected to result in a high rejection rate. Electrical stimulation offers the potential of creating ATS to restore tactile sensation. This paper proposed a portable wireless electrotactile stimulator, which can output common square wave (CSW), sine wave (SW) and time-varying pulse width square wave (TPSW), with a superior resolution. A preliminary experiment showed that the amplitude was easy to be distinguished compared to the frequency for all waveforms. The pulse width changing frequency of TPSW was more discernible than that of CSW and SW. Besides, the TPSW felt the most comfortable while the CSW felt the worst. Furthermore, the SW felt better compared with CSW, especially under the low-frequency and high-amplitude condition. Therefore, the method have a potential to alleviate the discomfort of electrotactile stimulation and achieve a smooth sensation.