基于人体关节点的三维重心计算与验证方法

Calculation and Verification Method of Three-Dimensional Center of Gravity Based on Human Joint Points

目的 探究基于机器视觉确定人体重心空间位置的乘系数法和力矩合成法准确度。方法 搭建力学测量平台,分别设计静态和动态下人体三维重心测量方法,计算重心空间坐标。通过实验,分析乘系数法和力矩合成法的计算准确度。结果 在静态实验下,力矩合成法的计算结果在每个维度上都比乘系数法的准确度更高,力矩合成法计算人体三维重心在X、Y、Z方向上的误差最低分别为3.9%、4.1%、8.5%;在动态实验下,力矩合成法不论是在X或Y方向的平均误差和相对误差都比乘系数法要小,采用动作分解法来分析Z轴重心高度方向,力矩合成法最终呈现的效果更好。结论 力矩合成法的三维重心计算准确度较高,与力学测量平台的测量数据更接近。力矩合成法所计算出的三维重心基本可代替力学测量平台应用于后续进一步的研究。

Objective To explore the accuracy of the multiplication coefficient method and the moment synthesis method for determining the spatial position of the center of gravity(CoG) of the human body based on machine vision.Methods The mechanical measurement platform was built,and the three-dimensional(3D) human body CoG measurement method under static and dynamic conditions were designed to calculate the space coordinates of the CoG.Through experiments,the calculation accuracy of the multiplication coefficient and moment synthesis method were studied and analyzed.Results In the static experiments,the calculation results of the torque synthesis method were more accurate than those of the multiplication coefficient method for each dimension.The errors in the 3D CoG of the human body in the X,Y,and Z directions calculated using the torque synthesis method were 3.9%,4.1%,and 8.5%,respectively.In the dynamic experiment,the average and relative errors of the torque synthesis method in the X or Y direction were lower than those of the multiplication-coefficient method.When the action decomposition method was used to analyze the height direction of the CoG along the Z axis,the final rendering effect of the torque synthesis method improved.Conclusions The accuracy of the 3D CoG calculated by the moment synthesis method was relatively high,and was closer to the measurement data of the mechanical measurement platform.The 3D CoG calculated using the moment synthesis method can replace the mechanical measurement platform and can be used in subsequent studies.