Graduate School of Advanced Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo, 169-8555, Japan.
School of Materials and Chemical Technology, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo, 152-8550, Japan.
Nat Commun. 2023 Mar 13;14(1):1354. doi: 10.1038/s41467-023-37086-8.
The flourishing field of soft robotics requires versatile actuation methodology. Natural vibration is a physical phenomenon that can occur in any material. Here, we report high-speed bending of anisole crystals by natural vibration induced by the photothermal effect. Rod-shaped crystal cantilevers undergo small, fast repetitive bending (0.2°) due to natural vibration accompanied by large photothermal bending (1°) under ultraviolet light irradiation. The natural vibration is greatly amplified by resonance upon pulsed light irradiation at the natural frequency to realise high frequency (700 Hz), large bending (4°), and high energy conversion efficiency from light to mechanical energy. The natural vibration is induced by the thermal load generated by the temperature gradient in the crystal due to the photothermal effect. The bending behaviour is successfully simulated using finite element analysis. Any light-absorbing crystal can be actuated by photothermally induced natural vibration. This finding of versatile crystal actuation can lead to the development of soft robots with high-speed and high-efficient actuation capabilities.
蓬勃发展的软机器人领域需要多功能的驱动方法。自然振动是任何材料中都可能发生的物理现象。在这里，我们报告了通过光热效应引起的自然振动来实现苯甲醚晶体的高速弯曲。棒状晶体悬臂梁由于自然振动而经历小而快速的重复弯曲（约 0.2°），并且在紫外光照射下会发生大的光热弯曲（约 1°）。通过在自然频率下对脉冲光进行共振照射，自然振动得到极大放大，从而实现了高频（约 700 Hz）、大弯曲（约 4°）和高光能到机械能的能量转换效率。自然振动是由晶体中由于光热效应而产生的温度梯度引起的热负荷引起的。使用有限元分析成功模拟了弯曲行为。任何光吸收晶体都可以通过光热诱导的自然振动来驱动。这种多功能晶体驱动的发现可以为具有高速和高效驱动能力的软机器人的发展提供帮助。
