DualEMS: Two-Channel Arbitrary Waveform Electrical Muscle Stimulation Device to Design Interference Stimulation

We propose a device to design interference stimulation, which has not been feasible in HCI. Also, we suggest parameters of stimulus pulses and electrodes' placement that facilitate stimulation of the supinator muscle (deep muscle). EMS (Electrical Muscle Stimulation) has been used in the medical field for a long time and, more recently, has been applied to HCI. It has been noticed that the diversity of stimulus pulses enables new stimulation methods. However, there is no compact EMS device that can output arbitrary waveforms in multichannel. Therefore, we developed "DualEMS", which can simultaneously output arbitrary waveforms with two channels. The user study validated the performance of the DualEMS, as it was possible to achieve the forearm pronation with the previously proposed method and the forearm supination with the newly proposed approach. In the future, we expect to realize new stimulation methods and interactions by using this system and approach.