Markou Athanasios A, Baroudi Djebar, Cheng Qiang, Bordbar Hadi
Department of Civil Engineering, Aalto University, Rakentajanaukio 4A, Espoo 00076, Finland.
Department of Mechanical Engineering, Aalto University, Otakaari 4, Espoo 00076, Finland.
Data Brief. 2023 Jan 18;46:108913. doi: 10.1016/j.dib.2023.108913. eCollection 2023 Feb.
A folded chain hanged by its two ends in U-shape at the same level with an opening, distance, between its two tips is known as U-folded chain, as studied in Markou et al. (2023). When one of the tips is fixed and the other one is released, the free tip of the U-folded falling chain accelerates faster than gravity, due to momentum conservation. This counterintuitive fact has long excited mechanicians around the globe. In the current paper we present a group of datasets (tip's coordinate timeseries), comprising three different subsets of this variable-mass dynamical system. A series of experiments of a U-folded falling chain of length 1.51m with total mass 31 gm, have been recorded with a high-speed imaging (2000fps) (Markou et al., 2023). The distance between the tips of the chain (opening) varies throughout the experimental session series: (i) 0.045m, (ii) 0.087m and (iii) 0.128m. Three timeseries of the tip's coordinates (x,y) have been extracted using an edge detector based method, from the recorded high-speed videos.
如马尔库等人（2023年）所研究的那样，一条链两端悬挂成U形，处于同一水平高度，两端之间有开口（距离），这种链被称为U形折叠链。当U形折叠链的一端固定，另一端松开时，由于动量守恒，下落的U形折叠链的自由端加速速度比重力还快。这一违反直觉的事实长期以来一直激发着全球机械学家的兴趣。在本文中，我们展示了一组数据集（端点坐标时间序列），该数据集包含这个变质量动力系统的三个不同子集。我们使用高速成像（2000帧/秒）记录了一系列实验，实验对象是一条长度为1.51米、总质量为31克的U形下落链（马尔库等人，2023年）。在整个实验系列过程中链两端之间的距离（开口）各不相同：（i）0.045米，（ii）0.087米，以及（iii）0.128米。我们使用基于边缘检测的方法从记录的高速视频中提取了端点坐标（x，y）的三个时间序列。
