State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096, China.
Adv Sci (Weinh). 2024 May;11(18):e2306129. doi: 10.1002/advs.202306129. Epub 2024 Mar 6.
Plants can autonomously adjust their growth direction based on the gravitropic response to maximize energy acquisition, despite lacking nerves and muscles. Endowing soft robots with gravitropism may facilitate the development of self-regulating systems free of electronics, but remains elusive. Herein, acceleration-regulated soft actuators are described that can respond to the gravitational field by leveraging the unique fluidity of liquid metal in its self-limiting oxide skin. The soft actuator is obtained by magnetic printing of the fluidic liquid metal heater circuit on a thermoresponsive liquid crystal elastomer. The Joule heat of the liquid metal circuit with gravity-regulated resistance can be programmed by changing the actuator's pose to induce the flow of liquid metal. The actuator can autonomously adjust its bending degree by the dynamic interaction between its thermomechanical response and gravity. A gravity-interactive soft gripper is also created with controllable grasping and releasing by rotating the actuator. Moreover, it is demonstrated that self-regulated oscillation motion can be achieved by interfacing the actuator with a monostable tape spring, allowing the electronics-free control of a bionic walker. This work paves the avenue for the development of liquid metal-based reconfigurable electronics and electronics-free soft robots that can perceive gravity or acceleration.
植物可以根据向重力性反应自主调整生长方向，以最大限度地获取能量，尽管它们没有神经和肌肉。赋予软机器人向重力性可能有助于开发无需电子设备的自调节系统，但这仍然难以实现。本文描述了一种加速度调节软致动器，它可以利用液态金属在其自限制氧化皮中的独特流动性来响应重力场。软致动器是通过在热响应液晶弹性体上磁打印流体液态金属加热器电路获得的。通过改变致动器的姿势来调节重力调节电阻中的液态金属电路的焦耳热，从而可以对其进行编程。致动器可以通过其热机械响应和重力之间的动态相互作用自主调整其弯曲度。通过旋转致动器，还创建了一个具有可控夹持和释放功能的重力交互软夹爪。此外，还证明了通过将致动器与单稳态胶带弹簧接口，可以实现自调节的振荡运动，从而可以实现无需电子设备控制的仿生步行者的控制。这项工作为开发基于液态金属的可重构电子设备和无需电子设备的软机器人铺平了道路，这些机器人可以感知重力或加速度。
