Birds take off and land on a wide range of complex surfaces. In contrast, current robots are limited in their ability to dynamically grasp irregular objects. Leveraging recent findings on how birds take off, land, and grasp, we developed a biomimetic robot that can dynamically perch on complex surfaces and grasp irregular objects. To accommodate high-speed collisions, the robot’s two legs passively transform impact energy into grasp force, while the underactuated grasping mechanism wraps around irregularly shaped objects in less than 50 milliseconds. To determine the range of hardware design, kinematic, behavior, and perch parameters that are sufficient for perching success, we launched the robot at tree branches. The results corroborate our mathematical model, which shows that larger isometrically scaled animals and robots must accommodate disproportionately larger angular momenta, relative to their mass, to achieve similar landing performance. We find that closed-loop balance control serves an important role in maximizing the range of parameters sufficient for perching. The performance of the robot’s biomimetic features attests to the functionality of their avian counterparts, and the robot enables us to study aspects of bird legs in ways that are infeasible in vivo. Our data show that pronounced differences in modern avian toe arrangements do not yield large changes in perching performance, suggesting that arboreal perching does not represent a strong selection pressure among common bird toe topographies. These findings advance our understanding of the avian perching apparatus and highlight design concepts that enable robots to perch on natural surfaces for environmental monitoring.

中文翻译：

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在树栖环境中受鸟类启发的动态抓取和栖息

鸟类在各种复杂的表面上起飞和降落。相比之下，目前的机器人在动态抓取不规则物体的能力方面受到限制。利用最近关于鸟类如何起飞、降落和抓握的发现，我们开发了一种仿生机器人，它可以动态地栖息在复杂的表面上并抓取不规则的物体。为了适应高速碰撞，机器人的两条腿被动地将冲击能量转化为抓握力，而欠驱动的抓握机构在不到 50 毫秒的时间内环绕不规则形状的物体。为了确定足以成功栖息的硬件设计、运动学、行为和栖息参数的范围，我们在树枝上发射了机器人。结果证实了我们的数学模型，这表明较大的等距缩放动物和机器人必须适应与其质量不成比例的更大角动量，才能实现类似的着陆性能。我们发现闭环平衡控制在最大化足以栖息的参数范围方面起着重要作用。机器人的仿生特征的表现证明了它们的鸟类对应物的功能，并且机器人使我们能够以在体内不可行的方式研究鸟腿的各个方面。我们的数据表明，现代鸟类脚趾排列的显着差异不会对栖息性能产生很大变化，这表明树栖栖息并不代表常见鸟类脚趾地形中的强烈选择压力。