| 초록 |
Electronic skin (e-skin) has been attracted in the various fields including robotics, healthcare, wearable electronics, and medical applications. To achieve the highly-sensitive and ultra-fast e-skin comparable to human skin’s abilities, we suggest a novel bio-inspired design of hierarchical polydimethylsiloxane (PDMS) micropillar arrays decorated with ZnO nanowire (NW) arrays in an interlocked geometry. The interlocked and hierarchical structured e-skin based on ZnO NW arrays can perceive both static and dynamic tactile stimuli through piezoresistive and piezoelectric transduction modes, respectively. In addition, the interlocked and hierarchical bio-inspired design enables a stress-sensitive variation in the contact area between the interlocked ZnO NWs and also the efficient bending of ZnO NWs, which allow the sensitive detection of both static and dynamic tactile stimuli. Our piezoresistive mode of e-skin shows a high pressure sensitivity (-6.8 kPa-1) and an ultra-fast response time (＜5 ms), which enables the detection of extremely small stimuli such as minute static pressure (0.6 Pa), vibration level (0.1 m/s2), and sound pressure (~57 dB). On the other hand, the piezoelectric mode of e-skin can perceive fast dynamic stimuli such as high frequency vibrations (~250 Hz). The suggested design of our bio-inspired e-skin, which allows the simultaneous perceptions of static and dynamic tactile stimuli, may find applications requiring both static and dynamic tactile perceptions such as robotic hands for dexterous manipulations and various healthcare monitoring devices. |
