Department of Integrative Biology, University of Texas at Austin, Austin, Texas 78712, USA.
Bioinspir Biomim. 2021 Mar 2;16(2). doi: 10.1088/1748-3190/abe346.
I present the system PATMOS (paths and tessellated meshes from ORB_SLAM2) for measuring three-dimensional paths of animalsusing two handheld GoPro cameras and a small spatial reference object. Animal paths were triangulated from mobile camera positions obtained from a modified version of ORB_SLAM2, an open-source visual simultaneous localization and mapping software package. In addition to path calculation, this process provided a virtual three-dimensional surface approximation to the environment from which path to environment distances can be quantified. PATMOS can also fit a tranquil water's surface to an analytic plane if there are a sufficient number of visible objects intersecting the water's surface and can track objects over the water's surfaces with a single camera by measuring the object with its reflection. This technology was highly portable, could follow moving animals, and gave comparable spatial and temporal resolutions to fixed camera systems that use commercial cameras. An investigation of falling objects yielded a gravitational constant measurement of 978 ± 40 cm s. I demonstrated PATMOS's utility in terrestrial and aquatic environments by quantifying dragonfly flight characteristics and the inter-spatial distances between substrate and damselfish.
我提出了系统 PATMOS（来自 ORB_SLAM2 的路径和镶嵌网格），用于使用两个手持 GoPro 相机和一个小的空间参考物体来测量动物的三维路径。动物路径是从 ORB_SLAM2 的修改版本获得的移动相机位置进行三角测量的，ORB_SLAM2 是一个开源的视觉同时定位和映射软件包。除了路径计算外，该过程还提供了环境的虚拟三维表面近似值，从中可以量化路径到环境的距离。如果有足够数量的可见物体相交于水面，PATMOS 还可以将平静的水面拟合到一个分析平面，并可以通过测量物体的反射来使用单个相机跟踪水面上的物体。该技术具有高度的便携性，可以跟随移动的动物，并且提供了与使用商业相机的固定相机系统相当的空间和时间分辨率。对落体的研究得出了重力常数测量值为 978 ± 40 cm s。我通过量化蜻蜓的飞行特征以及基质和鳉鱼之间的空间距离，展示了 PATMOS 在陆地和水生环境中的实用性。
