fig4

Figure 4. Fatigue resistance evaluation of the paper-based device. (A) The relationship between SPL and compressive strain. The compressive strain refers to the distance between the top and bottom electrodes of the paper-based device; (B) The collected displacement of the haptic feedback unit and SPL values of the loudspeaker unit at different times during the continuous pressing of 12 h (~43,200 cycles); (C) Comparison of SPL generated from paper-based device before and after the continuous pressing test; (D) The SNR in distinct excitation frequencies after the continuous pressing test; (E) Simulation of stress distribution for perforated support frame; (F) Comparison of fatigue resistance between perforated and non-perforated support frames. A fixed compressive strain of 30% is applied. The error bars in the figures represent the standard deviation, with an experimental sample size of three. SPL: Sound pressure level; SNR: signal-to-noise.