CAREER: Gait Transition Principles in Quadruped Robots

四足行走在自然界中无处不在，是未来许多机器人应用的一种很有前途的运动模式。利用它的多功能性可以在以高效和稳定的方式管理意想不到的和变化的地形方面发挥关键作用。理解为什么、如何以及何时使用某种步态是成功制造稳定、适应性强的机器人的关键。动物的步态转换标准涉及代谢成本、骨应力、肌肉生理学和社会刺激等生物学特性之间的复杂相互作用。通过研究动物来获得对机器人设计有用的一般原理是非常具有挑战性的。本项目利用适当的计算模型研究四足步态动力学特性的内在本质以及它们之间的转换。这些模型被选为仅代表四足步态的重要动力学特征，并过滤掉对机器人实现不必要的生物学方面。这些模型有助于从每个步态的能量学和稳定性分析中制定步态选择标准。步态选择标准是稳定步态转换控制器开发过程的基础。该项目旨在增进我们对四足移动的理解，为未来的应用做出贡献，如灾害应对机器人和新的交通系统。此外，该项目计划将研究成果与教育活动相结合。这门关于仿生机器人的新课程为学生提供了学习如何使用计算方法和物理机器人调查科学问题的机会。学生培训包括几项外联活动，如参加科学节和为K-12教育开发科学展览。

Quadrupedalism, pervasive in nature, is a promising locomotion mode for numerous future robotic applications. Utilizing its versatility can play a crucial role in managing unexpected and varying terrains in an efficient and stable manner. Understanding of why, how, and when to use a certain gait is central to successfully building stable, adaptable robots. Gait transition criteria in animals involve an intricate interplay among such biological characteristics as metabolic cost, bone stress, muscle physiology, and social stimuli. Obtaining general principles that are useful in design of robots by studying animals is very challenging. This project investigates the intrinsic nature of dynamic characteristics of quadrupedal gaits and the transitions among them by utilizing appropriate computational models. These models are selected to represent only important dynamic characteristics of quadrupedal gaits and filter out biological aspects that are not essential to the realization of robots. These models help to develop gait selection criteria from the energetics and stability analyses of each gait. The gait selection criteria constitute the basis of the development process of stable gait-transitioning controllers. This project aims to enhance our understanding of quadrupedal locomotion, contributing to future applications such as disaster response robots and new transportation systems. In addition, the project plans to integrate research results with educational activities. The new class on bio-inspired robot provides the opportunities for students to learn how to investigate scientific questions using computational methods and physical robots. The student training includes several outreach activities such as participation in science festivals and developing science exhibitions for K-12 education.