Niu Xiaojie, Yao Xiang, Dong Erbao
Institute of Advanced Technology, University of Science and Technology of China, Hefei 230026, China.
School of Engineering Science, University of Science and Technology of China, Hefei 230026, China.
Biomimetics (Basel). 2025 Jun 6;10(6):378. doi: 10.3390/biomimetics10060378.
Bio-inspired joints play a pivotal role in legged robots, directly determining their motion capabilities and overall system performance. While shape memory alloy (SMA) actuators present superior power density and silent operation compared to conventional electromechanical drives, their inherent nonlinear hysteresis and restricted strain capacity (typically less than 5%) limit actuation range and control precision. This study proposes a bio-inspired joint integrating an antagonistic actuator configuration and differential dual-diameter pulley collaboration, achieving amplified joint stroke (±60°) and bidirectional active controllability. Leveraging a comprehensive experimental platform, precise reference input tracking is realized through adaptive fuzzy control. Furthermore, an SMA-driven bio-inspired leg is developed based on this joint, along with a motion retargeting framework to map human motions onto the robotic leg. Human gait tracking experiments conducted on the leg platform validate its motion performance and explore practical applications of SMA in robotics.
受生物启发的关节在有腿机器人中起着关键作用，直接决定其运动能力和整体系统性能。与传统机电驱动器相比，形状记忆合金（SMA）致动器具有更高的功率密度和静音运行特性，但其固有的非线性滞后和有限的应变能力（通常小于5%）限制了驱动范围和控制精度。本研究提出了一种受生物启发的关节，该关节集成了拮抗致动器配置和差动双直径滑轮协作，实现了放大的关节行程（±60°）和双向主动可控性。利用综合实验平台，通过自适应模糊控制实现了精确的参考输入跟踪。此外，基于该关节开发了一种SMA驱动的受生物启发的腿部，以及一个将人类运动映射到机器人腿部的运动重定向框架。在腿部平台上进行的人类步态跟踪实验验证了其运动性能，并探索了SMA在机器人技术中的实际应用。
