G.W.W. School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.
Soft Matter. 2017 Aug 23;13(33):5558-5568. doi: 10.1039/c7sm00759k.
In this work, we advance printed active composites by combining 3D printing, printed electronics, and liquid crystal elastomers (LCEs) to achieve soft actuators with free-standing two-way shape changing behaviors. Incorporated LCE strips are activated by Joule heating produced by printed conductive wires, while uniaxial deformation of the LCE strip is utilized as a driving force to achieve bending in the printed composite. The bending behavior of laminated hinges is first characterized in order to obtain a precise control of actuation, which is then exploited to actuate four demonstrative designs: a morphing airplane, a miura-ori structure, a cubic box, and a soft crawler. The soft morphing airplane and miura-ori structure are designed and fabricated with multiple laminated hinges to demonstrate the synergistic actions during actuation. The cubic box is constructed to show the capability of sequential folding by implementing multiple groups of conductive wires to achieve accurately addressable heating with temporal control. Finally, the two-way transformation is utilized as a driving force for the locomotion of a soft crawler stimulated by a periodic rectangular wave current. These examples show the great potential of using the hybrid 3D printing and pick-and-place method and using LCEs to achieve controllable shape change structures for a variety of potential practical applications.
在这项工作中，我们通过结合 3D 打印、印刷电子和液晶弹性体 (LCE) 来推进打印活性复合材料，以实现具有独立双向形状变化行为的软致动器。嵌入的 LCE 条带通过由印刷导电丝产生的焦耳加热来激活，而 LCE 条带的单轴变形被用作实现打印复合弯曲的驱动力。首先对层压铰链的弯曲行为进行了表征，以便对致动进行精确控制，然后利用该控制来致动四个示范设计：变形飞机、折纸结构、立方盒和软爬行器。软变形飞机和折纸结构采用多个层压铰链设计和制造，以展示致动过程中的协同作用。立方盒的构建展示了通过实现多组导电丝来实现顺序折叠的能力，从而实现具有时间控制的可精确寻址加热。最后，将双向转换用作周期性矩形波电流刺激的软爬行器运动的驱动力。这些示例展示了使用混合 3D 打印和拾放方法以及使用 LCE 来实现各种潜在实际应用的可控形状变化结构的巨大潜力。
