Fig. 3: Performance evaluation of four unimodal sensors and integrated unimodal sensor (i-US).
From: Flexible unimodal strain sensors for human motion detection and differentiation
a Piezoelectric responses of each unimodal sensor under the same tensioning (1% strain), bending (20° bent angle), twisting (30° twisted angle), and shearing (0.015 shear strain) conditions. Schematics of unimodal tension, bend, twist, and shear sensors with their corresponding deformations are shown in right insets. b Normalized Vp-p of unimodal tension, bend, twist, and shear sensors under tensioning, bending, twisting, and shearing deformation conditions. c Comparison of the piezoelectric response between the four unimodal sensors and the conventional single-layer PLLA sensors under the above conditions (Fig. 3a). d Shielding performance of the unshielded PLLA45 sensor and the self-shielded unimodal tension sensor (I) under the static condition and (II) when walking/running next to two sensors. e Schematic of the i-US comprising unimodal tension, bend, twist, and shear sensors (left). The right panels show the piezoelectric response of the i-US under the tensioning, bending, twisting, and shearing conditions. All conditions are the same as those used for individual unimodal sensor a.
