Synchronized Measurement of Electromechanical Responses of Fabric Strain Sensors Under Large Deformation

Fabric-based strain sensors hold significant potential across various applications, including sports, healthcare, rehabilitation, etc. Nonetheless, their complex performance under large deformation and varying loading rates, arising from material viscoelasticity and textile structure intricacies, remains inadequately understood. The primary constraint in evaluating their performance lies in the absence of electromechanically coupled instrumentation. This paper endeavors to overcome the limitation by developing a synchronized measurement system, which integrates mechanically controlled loading, voltage divider circuits, and visual measurement technologies. This system enables synchronized acquisition of mechanical and electrical signals spanning from 0.01 mm/min to 6 m/s, by employing material testing machines for low-speed loading and split Hopkinson pressure bars for medium-to-high-speed loading, and combining electrical performance measurements with displacement and strain field analyses. Experiments revealed that sensor sensitivity increased linearly with the logarithm of loading rates, while deformation patterns evolved with loading speed, thereby offering valuable insights into design and calibration of fabric-based strain sensors under dynamic conditions.