激光线扫描足部三维测量方法及其应用

3-D foot measurements using laser-linescanning

基于激光线扫描和力传感器原理设计了可以同时测量足部负荷和三维形貌的扫描仪。利用5mm以下足部投影轮廓线和整个足部投影轮廓线自动识别足后跟点和趾尖点,建立足部坐标系,并根据有关截面特征对其他特征点进行识别,自动提取足围等10项足部参数。对170名受试者进行了不同负荷下的足部参数测量,给出了零负荷下男性和女性的足部参数统计结果以及半体重负荷、全体重负荷和背负荷下足部参数的变化特性,并对正常足和扁平足的足部参数进行了对比。测量结果表明:男性和女性的平均足长和平均足围差异度较大,而平均足弓高差异度较小;当负荷增加到一定程度时,足部姿势发生改变,足后跟宽、足面高和外踝高等参数不再随负荷进一步增加有明显的变化规律。

A foot scanner was developed using laser-line scanning with mechanical sensors to simultaneously measure foot loads and 3-D foot shapes. A local foot coordinate system was defined with the pternion and acropodion extracted from the boundary of the foot projections of all foot points and of points within 5 mm of the ground. The characteristic points can thus be located with ten foot parameters automatically extracted using the local foot coordinate system and related sections. 170 participants were measured for various loads to obtain foot parameters for male and female participants for unweighted, half-body-welght, full-body-weight, and over-body-weight conditions, with parameters of normal feet and flat feet also compared. The results show significant differences in the average foot length and average ball girth between male and female participants with no significant difference in the average arch height. The relationship between foot parameters and foot loads is quite regular, but the heel width, instep height and lateral malleolus height do not conform to the relationship when the foot load is increased to the point that leads to foot posture change.