共查询到20条相似文献,搜索用时 109 毫秒
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3D照相打印馆人像的打印质量取决于3D扫描获得的三维人体模型的辨识度.然而,由于现有3D人体扫描仪价格昂贵、操作复杂等原因,使得3D人像打印成本高、耗时长和打印精度较低.针对这些缺点提出一种基于深度扫描仪重建高辨识度三维人体模型方法.利用多组深度扫描仪分工协作、优势互补,分别获取高辨识度的人体面部五官点云数据,上半身与全身表面轮廓点云数据.然后,通过引入特征点和改进的最近点迭代法将采集到的三组点云数据进行对齐、替换、拼接,将拼接后的无拓扑关系的点云数据进行曲面重构即可获得高辨识度的三维人体模型.该方法的扫描时间较短,以较低的成本构建了具有高辨识度的三维人像模型. 相似文献
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基于Pro/E的人体特征尺寸提取 总被引:1,自引:0,他引:1
根据三维服装CAD系统对三维数字化人体尺寸特征信息的需要,提出了一种提取人体特征尺寸的新方法.该方法可根据人体扫描数据重构人体曲面模型,而后将模型导入Pro/E中,通过创建水平基准面与人体表面求交,找出人体主要特征尺寸如颈围、胸围、腰围、臀围所在的截面轮廓曲线特点,以此设定搜索这些特征截面轮廓曲线需满足的条件,利用Pro/E的测量分析和优化特征分析功能进行求解,从而获得满足设定条件的人体截面轮廓曲线所在的位置,最终计算截面轮廓曲线的长度以得到人体特征尺寸.该方法具有操作简便,易于掌握的特点. 相似文献
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文章论述了人体测量学的发展历程并介绍了先进人体测量系统。重点介绍了数字化三维人体模型这一最新技术,实例论述了人体模型在各个领域的应用,并展望了人体模型的发展前景。 相似文献
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本研究采用细分网格建模方法,建立表面光滑的人体模型,利用细分曲面的层次性数据结构和多分辨率特性,极大的减少了人体模型的数据存储。运用四元数CCD改进算法,满足多关节运动系统实时性,实现了在三维空间中人体模型的手臂运动控制与姿态仿真构建。据此算法运用于汽车驾驶室初步构建了对其空间布局的评价和修正的基本框架。 相似文献
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由于暖体假人的对流及辐射散热特性与实际人体非常接近,因此,在热环境工效学研究中发挥着突出的作用。该文介绍了几种通过暖体假人实验得到的热环境评价指标,提出了用暖体假人测定湿球黑球温度的好处,给出了各指标的计算公式,并对它们作了简单的分析。最后,将各指标与平均辐射温度进行了列表对比。 相似文献
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Physical phantoms are used at whole-body-counting (WBC) laboratories to calibrate detector systems for in vivo monitoring of radionuclides internally deposited in the body. Such phantoms should realistically represent the human body in the selected measurement geometry. In the past, the bottle manikin absorption phantom was used for calibration purposes at the laboratory for Anthropogammametry of SCK?CEN (American National Standard Institute. Specifications for the bottle manikin absorption phantom. ANSI/HPS N13.35, 1999). However, it was considered inadequate because of the leakage risk and the volume of radioactive waste produced at each calibration. As a consequence of this fact, a new phantom was developed. The Emma phantom is made of Epramid blocks (cylinders, cuboids and elliptical cylinders) in which sealed line sources can be introduced. The phantom is modular; so different body geometries can be made. This paper presents the phantom with its sources. The phantom was used to calibrate the SCK?CEN WBC setup. Efficiency calibration curves were obtained for different body geometries. The results of the calibration are discussed. 相似文献
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利用微焦点工业CT对混凝土试件单轴压缩过程分阶段进行原位扫描,获得相应的系列CT图像。由数字体散斑法(Digital Volumetric Speckle Photography,DVSP)获得了试件内部三维位移场与应变场。混凝土内部非均匀细观结构可以作为散斑结构成为变形信息的载体用于试件内部变形的测量;通过位移场和应变场的分析,揭示了试件内部变形局部化区域的演化及破坏过程,局部化区域与试件最终破坏面位置相一致。根据试件的体积应变随轴向应力的变化曲线分别定义了小于CT尺度微裂隙和CT尺度裂隙的发育点,分别为峰值应力的54.7 %和82.0 %,这两点同时对应着试件扩容的起始点及塑性变形的起始点。结果表明,DVSP与CT技术相结合能够直观地揭示混凝土试件内部变形局部化产生及发展过程,为三维变形的精细测量及可视化提供了方法。 相似文献
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We describe multifocal multiphoton microscopy giving images without laser scanning. A multitude of 8 x 8 laser beams is focused into a sample yielding two-photon excitation in a plane. The focal spots are arranged in a rectangular array with close spacing between individual points (approximately 0.5 microm). The fluorescence emission from the sample is recorded with a CCD camera, but, owing to the close distance between the beams, they can no longer be regarded as individual points but rather as an illumination of the plane that is covered by the array of focal points. The axial sectioning capability is comparable with an ordinary single-beam two-photon microscope. Interference between the beams that could compromise the axial sectioning capability does not occur in our setup owing to small temporal delays between the individual beams. The axial sectioning capability of the setup is discussed in detail by means of the step response in which the foci are scanned axially into a uniformly fluorescent medium. 相似文献
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大型刚体惯性参数识别的三线扭摆系统实验方法改进研究 总被引:2,自引:0,他引:2
精确获取汽车动力总成刚体惯性参数是发动机悬置系统设计的重要前提之一。利用三线扭摆法测量刚体单轴转动惯量精度较高的特点,基于表面固定点确定刚体方位的三点定位方法和测量6个~9个不同方位的多次测量原理,发展了一套适合于大型复杂刚体的惯性参数识别方法。关键技术有:(1)选取刚体表面三个定位点定义一个刚体随动坐标系以描述刚体方位;(2)通过测量刚体定位点至托盘表面参考点(定义一个整体坐标系)的距离,计算出定位点在整体坐标系下的坐标和两个坐标系之间的转换关系;(3)求出各组实验中在动坐标系下的刚体转轴方位和转动惯量;(4)运用最小二乘原理,求解多个转轴的最优交点得到动坐标系下的刚体质心坐标,求解由转动惯量转轴定理导出的线性方程组得到刚体惯性矩阵。实验方法中容易引起误差的环节较多,但是可以根据最小二乘原理进行逐级误差估计和控制。通过误差分析、长方体质量块实验验证和大量的汽车动力总成惯量参数识别实验,证明了该方法的实用性和可靠性。 相似文献
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Orouji T Hosseini Pooya SM Jafarizadeh M Khosravi HR Rais Mohammad H 《Radiation protection dosimetry》2011,147(1-2):227-229
The X-ray body scanner (BS) is going to find common use as a body-checking equipment at the entrance borders of countries, to find illicit drugs or forbidden items which have been hidden inside the body cavities, or attached to the body parts of the passengers. Considering the tissue weighting factors of the sensitive organs, the total effective dose due to the scanning by the system was estimated to be 3.8 μSv per scan. The ambient dose equivalent rates within the distance range of 300-40 cm from the X-ray generator were measured to be 4.5 up to 50 μSv h(-1). It is concluded that, in general, BS systems could be a safe device for the operators and people who are being scanned. But using such systems should be justified for everybody and special care should be taken for children and pregnant ladies. 相似文献