Detecting strumming action while playing guitar

In this paper we describe a wristwatch-like device using a 3-axis gyro sensor to determine how a player is strumming the guitar. The device was worn on the right-handed player's right hand to evaluate the strumming action, which is important to play the guitar musically in terms of the timing and the strength of notes. With a newly developed calculation algorithm to specify the timing and the strength of the motion when the guitar string(s) were strummed, beginners and experienced players were clearly distinguished without hearing the sounds. The beginners as well as intermediate-level players showed a fairly large variation of the maximum angular velocity around the upper arm for each strum. Since the developed system reports the evaluation results with a graphical display as well as sound effects in real time, the players may improve their strumming action without playing back the performance.