Abstract
Due to the popularity of smartphones, the detection of electromyography (EMG) signals can be easily achieved and applied to many portable applications. By using wearable sensors combined with a microcontroller unit, we develop a portable multi-channel EMG signal detection system for Android-based smartphones. The communications interface between a smartphone and the connected microcontroller unit is the universal serial bus (USB) on-the-go (OTG) interface. Hence, our proposed system can be applied to an arbitrary Android-based smartphone easily without the compatibility problem.