皮肤位移对人手运动图像三维检测精度的影响

Effect of skin movement on the measurement accuracy of human hand 3-D motion

为研究皮肤位移对人手运动三维图像检测精度的影响 ,对食指 -拇指对捏运动过程进行了测试、分析。并在此基础上 ,利用人手运动三维图像实时检测装置 ,进行了标定实验 ,取得了较为理想的测量效果。分析表明 :1)在进行手指一般运动分析时 ,如果在手指上选择优化的标志点粘贴位置 ,标志点族的面积和长度相对变化量小于 5 % ,皮肤位移产生的影响基本可以忽略不计 ;2 )皮肤位移对各指节测量精度影响有所不同 ,远侧指节误差较小 ,近侧指节产生的误差较大 ;3)当对捏指的屈曲角度增大 ,对捏运动周期百分比达 6 0 %时 ,皮肤位移对检测精度的影响快速增大。

The influence of skin movement on the accuracy of 3-D measurements was studied by experimentally analyzing pinching of the index finger and the thumb. The results were used to develop a 3-D hand motion analysis system. Tests show that, 1) the relative deformation of the area and length of surface markers on the finger is less than 5%, when the optimal marker configuration for each segment is used, so the effect of skin movement on the analysis of finger motion can be negligible. 2) The skin motion has different effect in the measurement accuracy for different joints. Relatively larges errors accuse with the metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints, with small errors for the distal interphalangeal (DIP) joint. 3) The errors strongly correlate with the finger pinching motion, especially when the pinching cycle percentage reaches 60%.