数字光处理3D打印技术制备的基于形状记忆聚合物的变刚度软体执行器

软体执行器因其优异的环境适应能力和人机交互能力受到研究者们的青睐，然而依靠单一本征柔性材料所制备的执行器难以应用在需要较大载荷的环境当中。变刚度执行器因保留了软体执行器环境适应能力的同时具备了相应的变刚度能力从而可以完成相当的负载任务。形状记忆聚合物（SMP）因其在温度升高时会由玻璃态转变为橡胶态，模量可以实现较大跨度变换，正是这一特点使得其具备天然的变刚度属性，并且近些年来基于丙烯酸体系的SMP材料具有良好的可3D打印特性使得SMP材料成为变刚度方法中最具有潜力的解决方法之一。

近些年来，基于SMP材料制备的变刚度执行器，大多使用材料受限的商用材料来制备变刚度执行器，故而存在性能单一且不可调控的缺点。与此同时，众多的变刚度实现方法在追求制备简便与成品稳定程度上具备一定的矛盾性。如果使用简便的注模工艺来制备变刚度层，即会导致成品效果不稳定，同时如果使用较多集成商用打印设备来制备变刚度执行器，虽然可以保证制备的稳定性，但众多研究者们不具备如此高昂的实验条件。本研究尝试寻找一种快速便利且能够稳定的制备出性能较好的变刚度执行器的工艺制备方法。

本研究选择使用便利灵活的数字光处理3D打印技术，通过打印自主配制的性能可调控的光固化材料，并利用打印间隙将发热贴片嵌入其中，进而可以快速集成一体化制备变刚度执行器，后续并引入低熔点合金加强层在提高执行器变刚度能力的同时，进一步加快了变刚度效率。上述较为简便成熟的制备工艺为研究者们优化变刚度执行器的制备提供了一种可能的选择，其中的制备材料的使用、增强材料的选择、结构方面的优化以及加热冷却单元的布局等均可以深入研究改进，故而研究者们可以根据自身需求进行调整改进。

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