In this paper, an effort is made to obtain a lissjous pattern using daq card and measure the phase difference between two signals acquire by daq. Labview provides the flexibility of integration of data acquisition softwarehardware with the process control. Create a suitable vi to simulate a frequency estimator using lissajous pattern technique. A quick sketch that generates a lissajous curve using two randomly selected numbers from 010. Indeed you can find an example in labview about lissajous curve. Nidigital pattern driver download national instruments.
Rms voltage for sine and square waves, and why your dmm might not work right. Two small dc motors with a round mirror glued to the shaft under an angle are hit by a 5v laserbeam. If the two waves do not start at the same instant we get different patterns for the same frequency ratio. A labview based simulation of lissajous pattern using daq card. On an oscilloscope, we suppose x is ch1 and y is ch2, a is amplitude of ch1 and b is amplitude of ch2, a is frequency of ch1 and b is frequency of ch2, so ab is a ratio of frequency of two channels, finally. This is an article about lissajous curves lissajous curves sometimes also known as lissajous figures or bowditch curves, are pretty shapes first investigated by nathaniel bowditch in 1815, and later and in much more detail by jules antoine lissajou in 1857. To download ni software, including the products shown below, visit. Download scientific diagram distorted waveforms and the lissajous diagram.
Another simple lissajous figure is the parabola ba 2. Exp 4 oscilloscope xy mode, function generator and lissajous polar. Lissajous pattern obtain in labview having frequency ratio 3. The visual form of these curves is often suggestive of a threedimensional knot, and indeed many kinds of knots, including those known as lissajous knots, project to the plane as lissajous figures. To use lissajous figures to take frequency measurements. When this condition is met and when the phase shift is 0, the display consists of a straight line sloping upward from the left side of the screen to the right side. Lissajous pattern generator for beginners by willemvd. To view this page, you need a plugin called shockwave that you can download free from the web. It enables you to call pin and channel map, specifications, levels, timing, pattern, and waveform files you create in the digital pattern editor in the nidigital pattern driver labview or. Ive also attached that example just in case you dont find it. Discrete lissajous figures and applications article pdf available in ieee transactions on instrumentation and measurement 6312. Visually, the ratio a b determines the number of lobes of the figure.
Liassajou curves are described by the parametric equations below. The lissajous patterns for other frequency ratios can be similarly drawn. Some of these patterns are shown in the below figure. Nidigital pattern driver is an ni instrument driver that you can use to configure and control digital pattern instruments. Virtual instrument is a computer instrument system. Latest version of lissajous figure analysis and automatic phase estimation. Instantaneous phase difference analysis between thoracic and. The study adopted software waveform process with labview tool. Lissajous curve oscilloscope dual channel ni community.
To use lissajous figures to take phase measurements. A labview based simulation of lissajous pattern using daq. The story of how the abc logo came to be, plus a shockwave simulator of lissajous patterns. Labview provides the flexibility of integration of data acquisition softwarehardware with the process control application software for automated test and measurement applications. If you go help find examples in search tab just type lissajous and you will see a simple example. Sound card based oscilloscope, with all of the features of a modern digital storage oscilloscope, providing four types of views.
The simplest lissajous patterns appear in the oscilloscope display when the frequencies of the signals are the same, i. These can be fed back to the oscillocope in order to generate lissajous figures in the xy mode. Press any key to stop the generation and save the curve as an image in your sketch folder. Generating lissajous curves using labview ni community. Lissajous figures in the application of microvibration measurement article in optics communications 28118.
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