Liquid Crystal Elastomer with Integrated Soft Thermoelectrics for Shape Memory Actuation and Energy Harvesting
Liquid Crystal Elastomer with Integrated Soft Thermoelectrics for Shape Memory Actuation and Energy Harvesting
复制标题
具有集成软热电的液晶弹性体，用于形状记忆驱动和能量收集
DOI：
10.1002/adma.202200857
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发表时间：
2022
影响因子：
29.4
通讯作者：
Majidi, Carmel
中科院分区：
文献类型：
--
作者：
Zadan, Mason;Patel, Dinesh K.;Sabelhaus, Andrew P.;Liao, Jiahe;Wertz, Anthony;Yao, Lining;Majidi, Carmel
液晶弹性体（LCE）由于其机械和形状记忆特性而作为软机器人的致动器引起了极大的兴趣。然而，LCE致动器通常通过主动焦耳加热和被动冷却来响应热刺激，这使得它们难以控制。在这项工作中，LCE与柔软，可拉伸的热电元件相结合，以创建能够电控驱动，主动冷却和热能到电能转换的换能器。热电层由嵌入在3D打印弹性体基质中的半导体组成，并与共晶镓铟（EGaIn）液体金属互连线连接在一起。该层的两侧覆盖有LCE，LCE交替加热和冷却，以响应电压控制的Peltier激活实现循环弯曲驱动。此外，热电层可以通过塞贝克效应从两个LCE层之间的热梯度收集能量，从而允许再生能量收集。作为演示，首先，执行传感器的闭环控制以快速跟踪变化的致动器位置。其次，介绍了一种软机器人步行者，它能够向热源行走并收集能量。最后，示出了向光性激发的肢体朝向热源的自主偏转，展示了增加软系统能量回收效率的另一种方法。
Liquid crystal elastomers (LCEs) have attracted tremendous interest as actuators for soft robotics due to their mechanical and shape memory properties. However, LCE actuators typically respond to thermal stimulation through active Joule heating and passive cooling, which make them difficult to control. In this work, LCEs are combined with soft, stretchable thermoelectrics to create transducers capable of electrically controlled actuation, active cooling, and thermal‐to‐electrical energy conversion. The thermoelectric layers are composed of semiconductors embedded within a 3D printed elastomer matrix and wired together with eutectic gallium–indium (EGaIn) liquid metal interconnects. This layer is covered on both sides with LCE, which alternately heats and cools to achieve cyclical bending actuation in response to voltage‐controlled Peltier activation. Moreover, the thermoelectric layer can harvest energy from thermal gradients between the two LCE layers through the Seebeck effect, allowing for regenerative energy harvesting. As demonstrations, first, closed‐loop control of the transducer is performed to rapidly track a changing actuator position. Second, a soft robotic walker that is capable of walking toward a heat source and harvesting energy is introduced. Lastly, phototropic‐inspired autonomous deflection of the limbs toward a heat source is shown, demonstrating an additional method to increase energy recuperation efficiency for soft systems.