基于Kinect的树运动轨迹获取与振动频率分析

Trajectory Capture and Sway Frequency Analysis of Trees Based on Kinect

探索了一种低成本室外树复杂运动捕获方法,分析了树枝干运动与外力作用的关系。采用Kinect V2捕获树枝干运动;基于Mean Shift算法跟踪树枝干标记点并依据Kinect坐标转换原理提取树枝干三维运动轨迹;提出了一种用相对偏转角度量树枝干运动的方法,对偏转角度时域信号通过FFT变换获得频域信号。实验结果表明,树枝干在外力作用下的运动轨迹是近似环形的周期运动;树在不同外力作用下均以固定频率振动;同一类型树树形结构不同,其振动频率存在差异。

The morphology and structure of plants were complex. It is of great significance to investigate the inherent motion law of plants under the action of external force, such as realistic animation formation, plant pruning, vibration picking and forest protection. A low cost outdoor tree complex motion capture method was explored, and the relationship between the stem motion and the external force was analyzed. The Kinect was used to capture the branches motion; Mean Shift algorithm was used for tracking branches markers and the three-dimensional trajectory of the trunk was extracted according to the principle of Kinect coordinate transformation. A method of measuring the motion of a branch with relative deflection angle was proposed, and the frequency domain signal was obtained by the FFT transform of the deflection angle signal in time domain. Experimental results show that the trajectory of the tree trunk and branches under the action of external force is periodic motion of approximate circular; the sway frequencies of the trees under various external forces are almost same. Extra experiments indicate that there are differences in the sway frequency of the same tree with different tree structure.