Shoulder Angle Measurement by Optimized Strain Sensor Placement on Flexible Printed Circuit

In this study, we propose a new prototype wear attachment device with a flexible printed circuit made by screen printing technology. The new prototype placed 30 strain sensors at sportswear on clavicle, shoulder, and scapula. This study aimed to develop a new prototype with an optimized sensor arrangement and examine whether measuring the entire scapulas motion measurement accuracy. Four subjects wore the prototype and performed two basic motion tasks and two combined motion tasks. We evaluated the estimation accuracy of seven models determined based on three sensor group (clavicle, shoulder, and scapula) combinations. Normalized root mean square error (NRMSE) and Pearson correlation coefficient (ρ), calculated across in each model. As a results, model including all three sensor groups was more suitable than other models.