共查询到20条相似文献,搜索用时 109 毫秒
1.
2.
3.
本文借助微机,探讨相互垂直不同频率的两个简谐振动合成中的几个问题:(1)在什么条件下合运动具有周期性,合运动轨迹是稳定的闭合曲线;(2)李萨如图由哪些因素决定;(3)李萨如图(包括绕行方向)重复出现的规律. 相似文献
4.
用Matlab研究李萨如图形及其讨论 总被引:2,自引:0,他引:2
本文用Matlab6.5软件模拟示波器中的李萨如图形实验,并讨论振动中的频率、相位和振幅等多重因素对于李萨如图形生成的影响,同时简要地介绍了利用垂直简谐振动合成测量频率的实际应用. 相似文献
5.
6.
7.
我们设计制作了一种振动综合演示仪 ,不仅可以用它演示简谐振动、拍现象 ,还可以用来演示李萨如图形 ,并介绍了此仪器的结构和原理。 相似文献
8.
9.
10.
关于李萨如图形的一点讨论 总被引:1,自引:0,他引:1
当一个质点同时参与相互垂直的两个简谐振动时,一般说来合成振动十分复杂,且轨迹是不稳定的。但是当二分振动的频率 (或周期)成整数比时,共合振动才是一稳定的、有规则的李萨如图形。当两个振动的频率比是 1: 1,即 的,情况比较简单,用消元法可直接得到轨迹方程:从上述方程分析知道,轨迹只是的函数。 确定,李萨如图形是唯一的,与 1(或 2)无关。如 ,有这说明无论 或 2取何值,只要面轨迹就是正椭圆。图(1)中给出了频率比为1:1, 为几个不同值时的李萨如图(1)。 当两相互垂直振动的频率为其它整数比时,用消元法很难得到简单的轨迹方程,所以一般教… 相似文献
11.
12.
基于MATLAB的振动合成及左旋与右旋的动态模拟演示 总被引:1,自引:0,他引:1
应用MATLAB的图形功能,进行了相互垂直、不同频率的振动合成演示实验,很方便地得到李萨育图形.应用MATLAB图形连续播放命令,演示了相互垂直同频率的振动合成轨迹与其相位差的对应关系,使左旋与右旋等抽象的概念得以直观显现. 相似文献
13.
Zhijun Li 《Optics Communications》2008,281(18):4744-4746
Based on Michelson interferometer and phase generated carrier (PGC) homodyne demodulation technique, an optical interferometer system is built, and a novel method using the central angles of Lissajous figures to measure micro-vibration displacement is proposed. The Lissajous figures are obtained by synthesizing two interferometric signals that their vibration directions are orthogonal and their intensities are equal. Through theoretical analysis, software simulation and experimental test, it is concluded that the central angles of Lissajous figures have a linear relationship with the phase modulation coefficients and the micro-vibration displacements when the phase modulation coefficients are small. So the micro-vibration displacements can be directly obtained by measuring the central angles of Lissajous figures. The method is simple and convenient. The experimental results indicate that the micro-vibration displacements measuring range can reach 5-775 nm, with a resolution of about 5 nm. 相似文献
14.
通过二阶分裂算符法数值求解了二维含时薛定谔方程,研究了双色反向旋转圆偏振激光场作用下氩原子的高次谐波的产生.研究表明,双色反向旋转圆偏振激光场的幅值比对高次谐波发射的效率有较大影响,当幅值比为1.4时高次谐波的发射效率最高,并应用时频分析方法、经典三步模型以及利萨茹图形等解释了高次谐波发射的物理机制.研究了不同幅值比情况下谐波场的旋转偏振特性,发现对不同频段的谐波谱的电场进行叠加,谐波场的偏振特性随幅值比的不同而发生变化,但谐波场的旋向性与入射激光脉冲的旋向性相同,不受幅值比变化的影响. 相似文献
15.
Shenglai Zhen Bo Chen Liang Yuan Min Li Jing Liang Benli Yu 《Optics & Laser Technology》2010,42(2):362-365
In-phase and quadrature-phase (I/Q) signals often need to be formed in the laser interferometric vibration measurement technique. To avoid the disadvantages of traditional I/Q signals forming methods such as effect of piezoelectric ceramic (PZT) for generating high frequency carrier, or optical configuration with complicated structure, a novel interferometric vibration measurement sensor with quadrature detection is proposed. The sensor utilizes simple optical configuration which contains 1/8 wave plate to generate two I/Q signals, then the signals were processed by arctangent algorithm which is compiled by Labview software through data acquisition card. Theoretical analysis and experimental Lissajous figures synthesis prove the phase orthogonality of the two signals. The experimental results indicate that the system can measure the vibration displacement accurately. 相似文献
16.
由于机械扫描振子在振动区间存有一共振峰,故提出了采用选频放大器驱动电路消除振子在振动区间的非线性的设计,并应用于演示弦线驻波、共振和李萨如图等实验中. 相似文献
17.
Except for the Lissajous singularities, the singular Lissajous line is shown to be in existence, which is emergent from the
incoherent addition of two uncorrelated vector electric fields at arbitrarily different frequencies. The free-space propagation
of the emergent Lissajous singularities and singular Lissajous line and their interaction are studied theoretically and illustrated
numerically. 相似文献
18.
B. Liu 《Journal of sound and vibration》2003,262(1):45-64
An adaptive harmonic wavelet transform is developed by taking advantage of the flexibility of the generalized harmonic wavelets. It first constructs a partition tree, which contains a great number of disjoint partitions of the frequency axis of a signal with each corresponding to an orthogonal harmonic wavelet basis. Then it searches the tree for the partition to represent the signal most sparsely. Since the corresponding basis is adapted to the composition of the signal, the transform can well reveal its characteristics. This is demonstrated with analysis examples of some simulated and vibration signals as well as comparisons with the conventional orthogonal harmonic wavelet transforms and wavelet packet transform. 相似文献
19.
借助GoeGebra软件对简谐运动的振动图像进行拟合,解决了中学物理教师难以根据振动图像(x-t图)利用拟合法获得振动规律的困境. 相似文献
20.
对称非线性弹簧振子的周期特性 总被引:6,自引:1,他引:5
通过计算机编程(Quick Basic)描绘对称非线性弹簧振子振动的特性曲线,使难懂的物理过程变得直观、形象。对称非线性弹簧振子的振动是一种周期性振动,但不是严格的简谐振动,其振动周期随非线性系数、振幅的变化而偏离简谐振动的周期。 相似文献