Avian Terrestrial Locomotion: Evolution, Dynamics, and Computer Vision

两足动物的运动对大多数鸟类的生存至关重要。因此，鸟类是运动适应和专门化理论的天然试验台。到目前为止，近端肢体及其与刚性躯干的复杂耦合在很大程度上被研究忽视。繁琐的数据处理和必要的精密设置只允许进行几个示范性研究。通过将现有的数字双平面高速X射线技术与先进的(半自动)数据跟踪算法相结合，在形态学、运动学、动力学和建模方面进行比较研究，我们打算研究两足动物运动的一般原理和鸟类运动系统的适应性。我们将集中在三个水平上：个体运动差异，物种特定的形态和总体运动目标的全局策略，如速度或稳定性。有必要开发一种新的数据处理工具，以处理产生的海量数据，并满足对基于3Dx射线的逆动力学的极端要求。因此，这个项目将集成开创性的计算机视觉技术来自动跟踪特征点和重建3D运动。我们打算调查在皮带上行走和跑步时运动运动学的变化是否会转化为质心水平上的相应变化。然后，我们将探索12个精心挑选的物种在几何和形态上的差异是如何在局部和全局(COM)运动学和动力学中表现出来的。我们希望能够扩大我们对鸟类作为两足动物的腿、躯干和重心水平上的稳定性的理解，最终为鸟类进化的新视角做出贡献。

Bipedal locomotion is crucial for the survival of most bird species. Birds thus represent a natural testbed for theories on locomotor adaptations and specializations. Aspects of the proximal limb and its complex coupling to the rigid trunk in particular have been largely ignored by research to date. Tedious data processing and the necessarily elaborate setups have only permitted a few exemplary studies.By combining the available digital biplanar high speed x-ray technology with advanced algorithms for (semi-) automatic data tracking, comparative studies in morphology, kinematics, kinetics and modeling, we intend to investigate general principles of bipedal locomotion and adaptations of the avian locomotor system. We will focus on three levels: individual motor variance, species-specific morphology and global strategies for general movement goals such as speed or stability. It will be necessary to develop a new tool for data processing in order to handle the enormous amount of data produced and meet the extreme demands that will be placed on 3D x-ray-based inverse dynamics. As a result, this project will integrate pioneering computer vision techniques for automatic feature point tracking and the reconstruction of 3D motion.We intend to investigate whether the variability of the kinematics of locomotion while walking and running on a belt translates into corresponding variation at the level of the centre of mass. We will then explore how differences in geometry and morphology between 12 carefully selected species are expressed in local and global (COM) kinematics and kinetics. We hope to be able to expand our understanding of stability on the level of the leg, the trunk and the centre of mass in birds as bipedal animals, and finally to contribute to a new insight into avian evolution.