三维轮廓光切法测量的图像获取及处理

介绍了基于光切法的脚型三维轮廓测量原理，针对多CCD光切测量系统组成，提出一种使用中轴跟踪和改进测偏原理相结合的高精度提取轮廓光带中心线的新方法，详述了光切面轮廓图像的提取及处理过程，并通过对提取中心线的坐标变换，获得了完整的脚型断面轮廓数据。实验结果表明该方法处理效果令人满意。     

用于曲面轮廓测量的结构光视觉技术研究

复杂曲面零件在高新技术领域具有重要的应用价值,其面形测量技术逐渐成为制约这类零件制造性能的关键因素。结构光法属于一类非接触式三维测量方法,目前已成为机器视觉测量领域的重要分支。针对结构光法测量曲面轮廓涉及的关键技术问题,开展了国内外研究现状分析:阐述了结构光视觉系统装置的优化设计理念,分析了各类结构光编码算法的应用特点;论述了结构光系统标定方法的研究成果,总结了基于结构光法实现曲面轮廓重构的科研动态。结合研究现状与技术特点的分析,提出将结构光三维测量法应用于自由曲面等复杂面形测量,有望克服三坐标测量法、零位补偿干涉检测法等传统方法存在的不足之处。最后,对结构光法测量三维面形的发展趋势进行了预测。     

基于光切法的全三维量脚制鞋系统的设计和实现

介绍了基于光切法的全三维量脚制鞋系统。利用基于光切法的三维形貌扫描仪对足型进行测量,得到精度为±0.4mm的足型数据。根据足部关键参数,选择标准鞋楦。将脚型划分为多个特征段,足型数据和标准鞋楦的规则化点云拟合为NURBS曲线,各段内根据脚型的特点对标准鞋楦进行整体缩放以局部修改,利用能量优化原则同时修改控制点和权因子,对标准鞋楦进行修改,使其符合脚型的整体三维特点。定制鞋楦建模后,利用等距面法得到鞋楦的刀具加工轨迹并转化为通用格式的NC代码送入数据刻楦机进行加工,定制的鞋楦用于生产适合脚型的鞋子。该系统打破了根据有限的足部参数来选鞋的传统,真正实现了基于全三维足型数据的量脚制鞋。     

基于数字投影的嵌入式三维传感系统

对传统的三维测量系统体积过大,操作复杂的缺点,提出了使用低功耗高速数字信号处理器(DSP)的嵌入式三维视觉测量系统.该系统采用了基于相位测量轮廓术原理,使用数字投影法实现结构光照明,利用定点DSP处理器和FPGA硬件电路以及多线程软件技术实现了条纹结构光编码、编码图像采集和条纹分析的流水线处理过程.通过测量实验表明,该系统可以实现快速、准确地三维轮廓测量.     

基于激光扫描的脚型测量系统关键技术及可靠性研究

针对脚型参数低成本高可靠性自动测量问题,研制了一种基于激光扫描的脚型测量系统。该系统主要由线结构激光源、CMOS摄像头、扫描机构及其控制软件组成。采用最小面积外接矩形法、最大方差分割法以及灰度重心法等图像处理方法,实现了摄像头标定、足底扫描图像处理和足面线结构光图像处理等系统关键技术。为验证系统的可靠性及精度,46名志愿者应征参与到实验中,运用统计学方法,统计分析脚型参数的可靠性。研究结果表明,该脚型测量系统具有很好的可靠性和精度,满足脚型测量的需求。     

智能化三维表面粗糙度测量系统

针对我国现有的粗糙度测量仪器存在的问题及发展趋势,综合运用电子、机械、自动化等知识提出并设计了数字化、智能化方向的粗糙度测量系统;实现了探头的三维自动定位以及其运行机构,并采用了两个传感器同时测量待测零件轮廓和表面粗糙度的方式,简化了结构并提高了粗糙度测量仪的精度和性能.     

基于线结构光和足底扫描的足部参数测量研究

针对现有足部轮廓三维重构方法精度低,鲁棒性差,成本昂贵且不符合实际足部生物力学研究要求等问题,设计了一种利用光学测量技术实现无接触式足部参数测量的系统。该系统一方面通过对足底扫描图像处理,构建足底轮廓点云,分割足底压力区域,计算足底相关参数;另一方面利用线结构光技术,重构足面轮廓,将足底轮廓点云与足面轮廓点云在系统规定世界坐标系内融合,形成完整足部轮廓点云,根据定义计算足部围度等足部系列参数。通过搭建相应硬件平台对多组人体足部进行测量,实验结果表明系统能够快速、精确地完成足部三维重构,具有很好的鲁棒性。     

三维物体曲面的轮廓测试

本文阐述了位相轮廓的测量原理，在此基础上，对三维面形测量系统进行了设计，给出了测量结果，并对结果进行了讨论。     

基于空域均值法的双频三维轮廓测量

针对传统双频三维轮廓测量方法存在分辨率低、数据处理时间长等问题,提出基于空域均值的双频三维轮廓测量方法。该方法通过空域均值图像对采集到的包含物体深度信息的双频结构光图像进行处理,得到物体表面的真实深度信息,提高测量效率和测量精度。通过对物体模型的测量,证明由该方法构成的系统输入、输出满足线性关系,并且可以实现高效、高分辨率的三维物体轮廓测量。     

利用OpenGL实现三维物体测量数据的可视化

本文运用计算机视觉测量技术,将结构光法测得的反映物体轮廓形状的二维图像信息进行三维重构。充分利用OpenGL三维图形构造和渲染等功能,借助Visual C 6.0开发了一套三维物体重构系统,实现了三维物体测量数据的快速可视化。     

三维脚型测量中的标定及轮廓图像处理技术

本文主要描述了一个基于激光扫描的3CCD三维脚型测量系统,介绍了系统的测量原理以及系统的模块校准、光带轮廓线提取技术。     

Computerized girth determination for custom footwear manufacture

Good fitting footwear requires matching not just the linear dimensions of feet but their girths as well. Footwear fitters have been using manual measurements for a long time, but the development of computerized techniques and scanner technologies have now made automatic determination of different foot dimensions feasible. The resistance to using such computer measurements has been the lack of trust in the accuracy of the data. This paper proposes an approach to obtain the necessary girths of feet in order to customize footwear. The proposed approach attempts to simulate the manual measurement procedures, and its effectiveness is assessed through an experiment with 15 foot castings. The results show that the simulated measurements can be within 5 mm of the manual measurements if the measuring locations can be correctly identified. Linear regressions show that the differences between the manual measurements and the simulated measurements can be modeled with the addition of a systematic error term of less than 4 mm. The computerized acquisition of foot dimensions is a useful way forward for custom shoe manufacturers.     

3D measurement of feature cross-sections of foot while walking

Measurement of human body is useful for ergonomic design in manufacturing. We aim to accurately measure the shapes of human feet for the design of shoes, for which measuring the dynamic shape of the foot in motion is important because the foot deforms while walking or running. In this paper, we propose a method for measuring the anatomical feature cross-sections of the foot while walking. The dynamic shape of feature cross-section has never been measured, though those features are very basic and popular. Our proposed method is based on the multi-view stereo method. The target cross-sections are painted in individual colors (red, green, yellow and blue). Several nonlinear conditions are introduced in the process to find the consistent correspondence in all images. We show that the proposed method for dynamic measurement achieved the desired accuracy similar to existing 3D static foot scanners.     

Taiwanese adult foot shape classification using 3D scanning data

This study classifies the foot shapes of Taiwanese using 3D foot scanning data from 2000 males and 1000 females. Nine foot dimensions relative to foot length and absolute measures in the common foot length categories were applied to compare the gender differences. Using foot breadth in % foot length (% FL), ball of foot length in % FL and arch height in % FL as feature parameters, three foot shape types for males and females can be classified. Significant gender differences were found in seven of the nine foot dimensions. Females had greater ball of foot length than males (0.2% FL). When comparing feet of the same foot length, males had greater breadth, girth and height dimensions than females, except for toe height. In addition, ethnic differences in foot shape were also observed. The findings can provide very useful information for building gender-specific shoe lasts and designing footwear insoles.     

A method for measuring the thermal geometric parameters of large hot rectangular forgings based on projection feature lines

The online dimensional measurement of large hot forging is an important procedure in the forging process. Because of different production demands, the final geometrical shapes of large forgings are usually different (e.g. cylindrical columns, rectangular prisms). Forgings of different geometric shapes need to be measured along different dimensions. For rectangular forgings, the lengths primarily need to be measured. A generalized measurement system for different geometric shapes of forgings cannot provide the accuracy of measurement systems targeted at measuring a known shape. Based on the characteristics of the rectangular forgings, a thermal dimensional measurement system is proposed in this paper. The localization, rapid extraction of feature points and method for measuring the dimensions of rectangular forgings are presented. The proposed methods can easily and efficiently extract the feature points of the forging. The experiment results show that the method proposed in this paper has the advantages of high precision and high efficiency, which is appropriate for online measurement.     

糖尿病患者专用鞋内无线多传感器测量系统

介绍一种专为糖尿病患者而开发的鞋内无线多传感器测量系统.该系统共包括鞋内感测装置、便携式无线警报器及监察台3个部份.通过实时感测病患者脚部不同位置的压力、温度及湿度, 以便当被测参数超出预设的安全指标时发出提示铃声.此外, 所感测的参数可传送到监察台作全面分析.     

Neural network and multiple linear regression to predict school children dimensions for ergonomic school furniture design

The current study investigates the possibility of obtaining the anthropometric dimensions, critical to school furniture design, without measuring all of them. The study first selects some anthropometric dimensions that are easy to measure. Two methods are then used to check if these easy-to-measure dimensions can predict the dimensions critical to the furniture design. These methods are multiple linear regression and neural networks. Each dimension that is deemed necessary to ergonomically design school furniture is expressed as a function of some other measured anthropometric dimensions. Results show that out of the five dimensions needed for chair design, four can be related to other dimensions that can be measured while children are standing. Therefore, the method suggested here would definitely save time and effort and avoid the difficulty of dealing with students while measuring these dimensions. In general, it was found that neural networks perform better than multiple linear regression in the current study.     

Foot morphology in Spanish school children according to sex and age

The aim of this study was to analyse the differences in foot dimensions in a sample of Spanish school-aged children. A total of 497 boys and 534 girls from Spain participated in the study. Measurements of both feet were obtained using a 3D foot digitiser, and shoe sizes were recorded and then estimated based on foot length measurements. The variations in foot measurements underwent a gradual increase with age in both boys and girls. Gender differences appeared at the age of 8–9 years, when the girls in the sample were found to wear smaller shoes than those they should have worn. Most foot dimensions begin to differ between boys and girls at the age of 8 years. The girls in the sample studied used footwear that was too small for their foot length, probably because they looked for a better width fit.     

A Gait Phase Measurement System Using Treadmill Motor Current

The article describes the development of a gait phase time-based split-belt treadmill measurement system. Conventional methods of measuring gait phase, such as the foot switch and force plate, require significant preparation and are costly. In this article, we propose a simple, cheap, and accurate gait phase measurement system that utilizes only the treadmill motor current value. Comparison of this algorithm with conventional methods reveals that the proposed algorithm is as accurate as the foot switch. Moreover, the proposed algorithm can estimate stance phase within a 0.2?s error of the measured value of the force plate in most cases (four out of five healthy subjects). This accuracy is higher than that of the foot switch which is widely used in the clinical field.     

Integrated Computer Aided Shoe-Making System

Shoemaking is one of the areas where CAD/CAM application is rapidly increasing.Thispaper introduces an integrated computer aided shoemaking system including human foot measuring,last(wooden model)measuring,last CAD/CAM and pattern CAD/CAM.The project was supported bythe 7th national economical 5 year plan.High technologies,suh as digital image processing,patternrcognition,advanced geometrical modeling and a series of sophisticated equipments and devices are ap-plied in this integrated system.Parts of the system have become commercial products.