Wavy-shaped flexible capacitive strain sensor for multiple deformations recognition

In this study, a flexible capacitive strain sensor based on a novel wavy-shaped structure for multiple deformations recognition was developed. Based on the simplified deformation of the wavy-shaped structure, the capacitive response of the sensor under both stretching and compressing deformations was analyzed. To evaluate the performance of the sensor, both stretch and compression for the sensor unit were calibrated and characterized, with results showing excellent sensitivity for both deformations. The sensor unit also exhibits super high resolution and dependable durability, which demonstrates its extraordinary sensing ability. Furthermore, by using active capacitive shielding layers, the wavy-shaped flexible strain sensor can also recognize stretching and bending deformations. Finally, the developed flexible sensor was integrated on a wearable elbow sleeve for sensing the bending angle of the elbow joint, which demonstrates its performance in rehabilitation.