摘要
假肢接受腔是连接残肢和假肢的关键部件,假肢接受腔的定制质量和残疾人的体验直接相关。针对假肢接受腔定制中取模精度不高,修型依赖假肢技师经验等问题,在分析残肢表面特征的基础上,提出了残肢表面三维重建算法和接受腔修型方法。通过深度相机扫描残肢,计算残肢点云数据的快速点特征直方图(FPFH)特征,应用采样一致性初始配准(SAC-IA)算法和迭代最近点(ICP)算法分别实现了点云初始配准和精确配准,基于仿射变换的特性提升了点云配准精度,实现残肢表面高精度重建。通过有限元仿真分析了大腿残肢-接受腔系统的受力情况,得出残肢几何形状规则时普遍的正应力和剪切力分布情况,与假肢技师经验平台相结合提出了修型建议,应用3D打印技术实现了接受腔快速成型。实验与仿真表明,三维重建均方误差仅有2. 1 mm,接受腔修型方法可以与医师经验平台互补,应力最大可减少34 k Pa。
The prosthetic socket is the key component that connects the residual limb and prosthesis. The customized quality of the artificial limb receiving cavity is directly related to the experience of the disabled. In order to solve the problem of low precision of the mold taking in the customization of the artificial limb receiving cavity,high dependence of repair on prosthetic technicians and other issues,a three-dimensional reconstruction algorithm for the residual limb surface and a method for repairing the prosthesis socket are proposed by analyzing the surface characteristics of the residual limb in this article. In order to realize the high precision threedimensional reconstruction of the surface of the residual limb,depth camera is used to scan the residual limb,FPFH feature is used to calculate the feature of the point cloud,Sample consensus initial alignment( SAC-IA) algorithm and iterative closest point( ICP)algorithm are used to realize initial registration and accurate registration of point clouds. The accuracy of point cloud registration is improved based on the characteristics of affine transformation. Finite element simulation is used to analyze the stress of the limb-socket system. The normal distribution of stress and shear stress are obtained when the geometry of the residual limb is regular. Combining with the experience platform of prosthetic technicians,suggestions for repair are put forward. The 3 D printing technology is applied to the rapid prototyping of the prosthetic socket. Experiment and simulation show that the mean square error of 3 D reconstruction is only 2. 1 mm,and the repair method can complement each other with the doctor’s experience platform,and the maximum stress force can be reduced by 34 k Pa.
出处
《电子测量与仪器学报》
CSCD
北大核心
2018年第9期176-186,共11页
Journal of Electronic Measurement and Instrumentation
基金
国家自然科学基金(61671248,41605121)
江苏省重点研发计划(BE2018719)
江苏省“信息与通信工程”优势学科资助项目
关键词
假肢接受腔
三维重建
有限元仿真
3D打印
prosthetic socket
3D reconstruction
finite element simulation
3D printing
