基于特征输入的数控车床在线编程系统的研究

介绍了基于特征输入的数控车床在线编程系统。该系统包括图形输入和编辑,切削加工处理以及动态模拟等部分,研究了特征输入模式下零件图的处理以及刀具干涉的处理,并给出了系统实际应用的示例,其结果和ＦＡＮＵＣ１０Ｔ和ＳＦＡＰＴ处理的结果相同,具有理想的应用效果和良好的应用前景。     

实现测地线活动轮廓模型的改进变分水平集方法

传统的实现测地线活动轮廓（Geodesic Active Contour,GAC）模型的水平集方法中,采用迎风方案作数值求解,需要使用足够小的时间步长,在曲线演化的过程中需要重新初始化,故效率低,据此,给出一种基于测地线活动轮廓模型的变分水平集方法,引入了一个水平集函数的强制项,避免了重新初始化,简化了初始化的工作,通过实验证明了这种方法是有效的,稳定的。     

基于格网模型的等高线算法

提出了一种通过格网模型生成等高线的方法.通过计算规则格网模型中顶点的符号来确定等高线与格网中棱的交点数目,根据交点的数目和格网中心点的符号确定等高线的跟踪方向,对等高线上的点用样条曲线连接可得等高线.实验结果表明,此算法正确、有效,运行效率高.     

降雨分析系统的设计与算法

等值线是反映空间地理信息数据关系的最重要的表现方式之一,但编程实现等值线的绘制并用其进行GIS软件的二次开发却并不容易。在实际开发降雨分析系统的基础上介绍了在数据可视化和地理信息系统中非常重要的等值线绘制和轮廓图填充算法,并且给出了基于动态链接库和XML技术的模块化系统整体架构。实际的绘制效果与计算速度可与美国GoldenSoft公司的著名软件Surfer相媲美。降雨数据来源包括以数据库和文件存储的一切实测、遥感数据。该系统已在杭州、温州、上虞、金华、台州等多个地市的防汛抗旱部门投入使用,改变了原先等值线主要由手工绘制的情况。本系统可以同样用于等高线的绘制。     

Application of self-tuning fuzzy controller for a Cartesian manipulator on unknown contours

Owing to the relative difficulty in achieving contour tracking on 3D objects, this study presents a novel compliant motion controller by applying the self-tuning fuzzy control to have a Cartesian manipulator implement contour tracking on unknown contours. A data fitting method is also developed to reduce the noise errors of the measurement. Moreover, the radius compensating method is used to correct the measured data. The Cartesian manipulator is tested and calibrated beforehand. Results in this study demonstrate the feasibility of the control strategy proposed herein.     

基于微信小程序的人体尺寸测量系统

针对传统人体尺寸测量方法不能够实现远程、便捷式测量的问题,提出了一种基于微信小程序的人体尺寸测量系统应用于远程服装定制,设计开发微信小程序设置特定的轮廓获取含有3种姿态的人体图像数据集,采用u-net网络框架进行训练,提取人体轮廓特征图,经过openpose人体姿态估计算法定位人体骨节关键点,提取人体关键部位提取特征点,利用身高比例法、双椭圆模型拟合人体尺寸信息通过微信小程序反馈给用户.以手工测量为标准,人体尺寸测量中二维尺寸测量准确率达97.8％,三维尺寸准确率达89.5％,最终平均总误差为3.19％.实验表明,基于微信小程序的人体尺寸测量系统能够实现便捷式的人体尺寸测量及远程服装定制.     

目标电磁散射极点的不变性特征分析

对频域磁场积分方程在离散化的基础上进行了矢量分析，发现离散化后的矩阵方程中含有频率因子的算子矩阵仅包含了反映散射体形状的矢量信息，从而得出极点的分布只依赖于目标的外部形状信息这一结论；然后利用FDTD进行了仿真研究，从不同姿态角(散射方向)的后时响应数据中提取了极点，结果保持了较好的一致，进一步证实了目标姿态角的改变不会影响极点的分布这一特征。     

用UBET模拟塑性金属流动

本文以简单形状零件的模锻为例,论述了用上限单元技术(UBET)对塑性成形中金属流动过程进行模拟的方法步骤,探讨了UBET的应用。     

Optimized feed scheduling in three axes machining: Part II: Experimental validation

The optimized feed scheduling strategy, developed in part I of this paper, considers an optimal use of the feed drive systems. The low frequency dynamics of the different feed drive systems of the machine tool are identified. The resulting transfer functions are transformed into FIR filter and integrated with the planning of the tool trajectory. The effectiveness of the proposed feed scheduling strategy is demonstrated using ball end milling of a workpiece that provides variable cutting conditions along a nonlinear tool path. The performance of this strategy in terms of productivity, machining safety, and machining accuracy, is compared to a feed scheduling strategy based on control points. The proposed strategy has significantly improved the tracking and trajectory following characteristics. It achieves a good prediction of the feed rate of the different axes and consequently a better regulation of the cutting force. In addition, by increasing the feed rate, while respecting the different constraints, it improves the tool path accuracy and enhances the productivity.     

Wavelet modeling of contour deformations in Sobolev spaces for fitting and tracking applications

This paper proposes a new model for contour deformations using wavelets. This model uses Sobolev spaces to control the smoothness of the contour deformation. This formulation defines a probabilistic model that induces a prior distribution for contour deformation. Based on this distribution, the fitting problem is solved in Bayesian terms. The deformation model is also used to generate a prior dynamic model for contour evolution in time. This probabilistic model is then applied to solve the tracking problem. Computational results for several real-image problems are given for both the Kalman and condensation filters.