刚体转动惯量虚拟仿真测量方法

提出了一种测量复杂形状刚体转动惯量的新方法。借助Pro/E软件建立三维模型,导入ADAMS中添加约束和载荷进行仿真,在后处理模块测量物体的角速度和振荡周期,得出物体的转动惯量。以均质圆柱为例,运用仿真分析测量法求得均质圆柱的转动惯量,其结果与理论值十分吻合,证明该方法是可行的。     

一种考虑三线摆摆线质量的转动惯量计算方法及虚拟验证

刚体（航空发动机、汽车动力总成等）转动惯量与系统振动、耐久、稳定性等动力学性能紧密相关，提升刚体转动惯量测量精度对系统动力学分析具有重要意义。考虑摆线质量影响，基于能量守恒定律改进三线摆刚体转动惯量计算方法，建立三线摆测量系统的虚拟样机模型并进行验证，对比分析了改进方法与不考虑摆线质量的三线摆转动惯量计算方法的测量精度，进一步研究了匀质摆线的线密度和长度对转动惯量测量精度的影响规律。通过虚拟样机技术验证了改进计算方法比改进前测量误差降低了50%左右，可显著提高三线摆法测量精度。     

伺服系统速度环参数整定技术的研究

为解决伺服系统速度环参数整定这一难题,文中首先提出了一种精确易实现的转动惯量辨识算法;然后根据伺服系统数学模型,利用辨识的转动惯量得到速度环控制器的初步PI参数。考虑到实际系统中不可避免的存在非线性和各种干扰,接着利用遗传算法对计算的PI参数近一步优化,最终得到最优速度控制器参数。理论分析和实验验证了方法的正确性和实用性。     

洁净机器人手臂的转动惯量分析及运动控制

针对洁净机器人手臂的转动惯量对系统动态性能的影响,在利用动能公式分析得到其转动惯量与位置关系的基础上,提出了一种位置PI闭环加前馈参数整定的控制方法。该控制方法是由位置值实时得到转动惯量,再由转动惯量来实时整定PI参数。仿真结果表明了该控制方法能有效抑制转动惯量的变化对系统动态性能的影响,且简单可行。     

永磁同步电机转动惯量在线辨识关键技术研究

针对工程实践中电机转动惯量在线辨识方法中输入参数的异步性和噪声干扰,采用基于模型参考自适应的转动惯量辨识方法,并使用跟踪微分器对输入参数进行预处理来解决以上问题。对模型参考自适应和跟踪微分器这两种关键技术进行研究,为工程应用中普遍得不到理想转动惯量辨识结果的在线辨识方法提供了一个比较好的解决思路。实验表明:经过跟踪微分器预处理后,基于模型参考自适应的转动惯量在线辨识方法能获得比较理想的辨识效果。     

数控机床体积误差激光分步体对角线测量的优化方法

高精度数控机床已经在市场中广泛应用。为了保证机床在三维空间中的定位精度,需要对机床的体积误差进行测量。文章在传统的激光分步体对角线测量法的基础上,提出了一种简化的辨识方法,通过3条机床工作空间体对角线定位误差的测量数据,即可辨识获得与传统方法(测量4条体对角线)相同的结果,减少了测量时间。针对分步体对角线测量的安装误差,提出了一种优化的测量辨识方法,通过增加3个平动轴定位误差的测量,可以去除安装误差对测量结果的影响,提高了测量辨识精度,同时也不失高效性。运用上述测量方法在机床上实施体积误差测量实验,实验结果证实了文中提出的激光分步体对角线测量的简化方法和优化方法的有效性。     

基于体视显微镜的细观材料应变检测方法研究

提出了一种基于双目体视显微镜和数字图像相关技术来解决细观材料三维全场应变测量的方法,举例说明了传统的校准技术在校正立体显微镜畸变过程中存在的问题,进而提出了一种新颖的校准方法来对显微镜进行标定,从而获得较高的三维位移场和应变场测量精度。液压胀形实验的应变测量结果表明,该细观应变测量系统在测量细观材料表面全场应变时具有可行性,同时有限元模拟的结果与实验结果比较吻合,最大主应变的偏差在10%之内,证明了该系统可以准确地测量微小尺寸的材料应变。     

基于离散傅里叶变换的永磁同步电机驱动系统电流测量偏置误差在线补偿方法

电流反馈信息的准确测量是永磁同步电机驱动系统高性能运行的重要前提。对于实际控制系统,由于器件温漂、老化和非线性等各种因素,电流传感器和相关调理电路会出现电流测量误差,其中电流测量偏置误差将引起频率为一倍电频的转矩与转速脉动,降低永磁同步电机控制性能。在详细分析电流测量偏置影响的基础上,探究闭环控制对电流谐波幅值的影响,指出闭环控制系统将影响电流谐波幅值,传统分析结果不再成立。针对这一问题,提出一种基于离散傅里叶变换的永磁同步电机驱动系统电流测量偏置误差在线补偿方法。在电机运行过程中实时提取电流脉动并有针对性地进行电流测量误差补偿,以消除由于测量偏置误差导致的转矩与转速脉动。与传统方法相比,所提方法无需定子电阻或转动惯量等电机参数。最后,通过数控机床用交流永磁同步电机验证了所提算法的有效性。     

高温钢板边缘位置的图像测量方法

文章提出了一种钢板热膨胀率测量中的图像边缘检测方法.该方法对钢板降温过程中的收缩量进行测量,首先通过成像系统采集图像,然后采用一种基于灰度突变的区域边缘检测方法检测钢板的边缘,最后将边缘位置的像素坐标通过标定参数转换为物理坐标值,从而得到最终结果.实验表明,图像测量的方法能实现对高温钢板边缘位置的高精度实时非接触式测量.     

高温转向节锻件自动化三维测量与精度检测技术

阐释了一种高温锻件自动化三维测量与精度检测技术,通过工业机器人驱动面结构光三维测量设备从多个视角对高温转向节锻件进行测量,并将不同视角测量的数据统一到同一坐标系下,形成完整数据,提取关键尺寸,最终进行趋势分析。提出了一种双重滤波方法解决了高温物体表面图像高质量获取和相机热防护的问题;通过一种模型分区的可行域筛选方法解决了复杂零部件的测量视点规划问题;通过基于机器人重复性的无标志点数据拼合方法解决了高温物体测量数据的拼合问题。提出的关键技术在转向节锻造工厂实现了实施应用,并通过实验验证了相关方法的可行性和可靠性。     

A new method and device for motion accuracy measurement of NC machine tools. Part 2: device error identification and trajectory measurement of general planar motions

This paper describes in two parts a new method and device for measuring motion accuracy of NC machine tools. In the first part, the measurement principle and the characteristics of the prototype device have been presented and discussed. In the second part, an efficient and practical approach to identifying the errors of the proposed device after assembly is developed and evaluated. The approach ensures realising the aim of the investigation, i.e. to measure the most items of the motion accuracy, especially, to measure and assess the trajectory accuracy of a general planar motion of NC machine tools. The result of the identification experiment by using the prototype device on a machining centre for the prototype device is presented and it well verifies the validity and practicality of the approach. Some measurement results for the general planar motions of the machining centre are also shown, which sufficiently demonstrate the desirable capability of the proposed method and device.     

Radial error measuring device based on auto-collimation for miniature ultra-high-speed spindles

This study has developed a radial error measuring device for miniature ultra-high-speed spindles because it is very difficult to measure the radial error motion of miniature ultra-high-speed spindles by the conventional measurement method using capacitive-type displacement sensors. The authors have proposed an optical measurement method based on auto-collimation, which evaluates the radial error motion according to the movements of a laser beam reflected from a target sphere attached to the spindle end. This optical measurement method is suitable for radial error measurements of miniature ultra-high-speed spindles because of its applicability to a small target sphere, high-speed response and minor susceptibility to electric noise. In this paper, the measurement principle, and basic characteristics of the optical measurement method in addition to an approximate analysis are shown. The radial error motion of a miniature ultra-high-speed spindle with a steel ball 1 mm in diameter are measured by an optical measuring device designed and manufactured to implement the proposed method. The measurement results show that the optical measuring device is able to measure the radial error motion of ultra-high-speed spindles with a maximum rotational speed of 200 krpm.     

振动筛侧板强度分析及试验研究

按照有限元结构原理建立了直线惯性振动筛侧板强度分析模型，采用ＳＡＰ５软件，应用振型叠加法求侧板的动力响应。     

热线法在导热系数测量中的应用

在分析热线法测量原理的基础上，以建筑保温材料为例对其导热系数(不同温度下)进行了测量。并用Origin7．0对测量结果进行了数据分析，可快捷、精确地获得测量结果。     

A new method and device for motion accuracy measurement of NC machine tools. Part 1: principle and equipment

This paper describes in two parts a new method and device for measuring motion accuracy of numerical control (NC) machine tools. In the first part, the measurement principle and the characteristics of the prototype device are proposed. The device consists of a double-bar linkage with two rotary encoders. The working range of the device is disc-shaped with a radius of almost the double the link length, except a small area around the centre of the disc and an outer area both around the change points of the linkage at the centre and the circumference of the disc. Because the method has high resolution for any measuring point within the working range, it can be applied to measure most items of motion accuracy of NC machine tools. The method is particularly suitable to measure the trajectory accuracy of circular motions. The device has a compact structure and its installation on a machine tool to be measured is simple and quick. The experimental results show that the prototype device has very good response to small displacement and good repeatability with high precision to the measurement of circular motion trajectories. The influence of measurement noise is hardly observed in the experimental results.     

基于轮廓法测试镍基高温合金惯性摩擦焊接头内部残余应力

采用轮廓法(contour method)测试小直径FGH96镍基高温合金惯性摩擦焊接接头的内部环向应力。详细介绍了轮廓法测试步骤,包括试样切割、切割面轮廓测试、数据处理和有限元分析;获得了FGH96镍基高温合金惯性摩擦焊接接头内部环向应力分布全貌并分析其分布特征。测试结果表明:镍基高温合金惯性摩擦焊接接头的焊缝中心位置环向应力为非常大的拉应力,峰值拉应力为1200 MPa,达到材料室温时的屈服强度;焊缝区域(距焊缝中心±5 mm区域)近内壁区域的环向应力大于外壁区域环向应力,垂直焊缝方向的环向应力变化梯度非常大;远离焊缝区域,焊缝两侧的环向应力不对称。     

曲轴复合车床随动刀架动平衡分析及优化

曲轴复合车床采用随动刀架对连杆颈进行随动车削加工具有诸多优点,由于刀架在随动车削时随工件高速转动,若设计不当或平衡不好时会产生较大的惯性力与惯性力矩,严重影响加工效率和加工精度。提出针对随动刀架的一种新的动平衡配重方法,将刀架三维模型导入ADAMS仿真,并对平衡块质量进行优化,取得了良好的动平衡效果,为刀架的动平衡设计提供了一种新方法。     

A new approach to identifying the dynamic behavior of CNC machine tools with respect to different worktable feed speeds

The dynamics of the machine tool structure are important in high precision machining. Some researchers have studied that the dynamics are expected to change under different machining conditions. However, the dynamic behaviors of the machine tool at different worktable feed speeds are rarely studied. In this paper, an output-only modal identification available to predict the dynamics of the machine tool at different feed speeds is proposed. The excitation of this method uses the inertia force sequence caused by random idle running of the worktable. The first six modes of the entire machine tool structure are estimated using the proposed method. The results indicate that the running state of the worktable can influence the modes in which the worktable vibrates. The estimated natural frequencies and damping ratios decrease obviously as the feed speed increases. Furthermore, because this method enable to determine modal parameters by measuring the response of machine tool structure without using any artificial excitation, it can be used to predict the dynamic behaviors of the machine tool in entire working space effectively.     

基于XRD的薄膜界面结合强度试验研究

利用X射线衍射技术（XRD）分析了薄膜结合界面应力及其变化规律，通过对薄膜界面结合状态的检测，建立了X衍射法测量薄膜界面结合强度的原理、方法与过程。其检测界面结合强度方法可对薄膜试样进行非接触检测，适用于晶体或多晶体薄膜的界面结合强度测量，是一种研究无损检测薄膜结合强度的试验新方法。