液态金属的制备及其在软体机器人中的应用研究

液态金属(liquid metal, LM)是一种新型材料，具有完美的流动性和极佳的导电性能，可广泛应用于电子皮肤、可控电子开关、能源设备等领域。同时，它可以轻松制成液体线圈，密封在弹性体中作为柔性执行器。这种致动器具有良好的电磁效应，并表现出出色的驱动性能，为开发性能更好的全软体机器人提供了有力支持。最重要的是，液态金属具有良好的生物安全性，这使得该材料制成的软体机器人可以广泛应用于医疗领域。本文旨在利用镓基液态金属设计制造一种仿生蚯蚓软体机器人，该机器人应该能够模仿蚯蚓的身体结构和运行机制，并适应复杂的环境，如人体腔道、输油管道等。 本研究探讨了蚯蚓的身体结构和运动机理，以此为基础设计了一种仿生软体机器人。该机器人集成了液态金属线圈和柔性永磁体，因此具有全软体的特点。在软体机器人设计中，利用液态金属电磁驱动器模仿蚯蚓的静压流骨架结构，使机器人每个单元都具有独立的“收缩-伸长”能力。通过理论推导和有限元仿真，本研究系统地分析了软电磁致动器的驱动性能以及在工作时的发热情况，验证了该设计的可行性。根据软体机器人的结构和材料特性，采用复模工艺制造了机器人样机，并对其进行了性能表征。实验测量了机器人的运动速度与激励信号（电流幅值和频率）之间的关系，并发现最佳激励信号是幅值为5 A、频率为4 Hz的方波电流信号。此外，本研究还测量了机器人的爬坡性能，并发现其可以在摩擦系数为0.55、坡度小于30°的斜坡上轻松爬行。

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