Search and rescue (SAR) robots are required to quickly traverse terrain and perform high-force rescue tasks, necessitating both terrain adaptability and controlled high-force output. Few platforms exist today for SAR, and fewer still have the ability to cover both tasks of terrain adaptability and high-force output when performing extraction. While legged robots offer significant ability to traverse uneven terrain, they typically are unable to incorporate mechanisms that provide variable high-force outputs, unlike traditional wheel-based drive trains. This work introduces a novel concept for a dynamically extensible and retractable robot leg. Leveraging a dynamically extensible and retractable five-bar linkage design, it allows for mechanically switching between height-advantaged and force-advantaged configurations via a geometric transformation. A testbed evaluated leg performance across linkage geometries and operating modes, with empirical and analytical analyses conducted on stride length, force output, and stability. The results demonstrate that the morphing leg offers a promising path toward SAR robots that can both navigate terrain quickly and perform rescue tasks effectively.

翻译：搜救（SAR）机器人需要快速穿越地形并执行高力救援任务，这既要求地形适应性，又需要可控的高力输出。目前适用于SAR的平台较少，而能在执行救援时兼顾地形适应性与高力输出的平台更为罕见。尽管腿式机器人在穿越不平坦地形方面具有显著优势，但与传统轮式驱动系统不同，它们通常难以集成可提供可变高力输出的机构。本研究提出了一种动态可伸缩机器人腿部的新颖概念。通过采用动态可伸缩的五连杆机构设计，该腿部可通过几何变换在高度优势构型与力学优势构型之间进行机械切换。实验平台评估了腿部在不同连杆几何形状与工作模式下的性能，并对步幅长度、力输出及稳定性进行了实证与理论分析。结果表明，这种变形腿部为SAR机器人提供了一条可行路径，使其既能快速穿越地形，又能高效执行救援任务。