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><channel><title>Prosig Noise &#38; Vibration Blog &#187; orders : Noise &amp; Vibration Blog : What You Need To Know About Noise &amp; Vibration Measurement</title> <atom:link href="http://blog.prosig.com/tag/orders/feed/" rel="self" type="application/rss+xml" /><link>http://blog.prosig.com</link> <description>Telling you what you need to know about noise &#38; vibration</description> <lastBuildDate>Wed, 25 Jan 2012 14:42:00 +0000</lastBuildDate> <language>en</language> <sy:updatePeriod>hourly</sy:updatePeriod> <sy:updateFrequency>1</sy:updateFrequency> <generator>http://wordpress.org/?v=3.3.1</generator> <item><title>What is Synchronous (Angular) Sampling?</title><link>http://blog.prosig.com/2011/11/09/what-is-synchronous-angular-sampling/</link> <comments>http://blog.prosig.com/2011/11/09/what-is-synchronous-angular-sampling/#comments</comments> <pubDate>Wed, 09 Nov 2011 10:22:14 +0000</pubDate> <dc:creator>Adrian Lincoln</dc:creator> <category><![CDATA[featured]]></category> <category><![CDATA[signal processing]]></category> <category><![CDATA[acoustic]]></category> <category><![CDATA[acoustic data]]></category> <category><![CDATA[acoustics]]></category> <category><![CDATA[angle domain]]></category> <category><![CDATA[angular motion]]></category> <category><![CDATA[FFT]]></category> <category><![CDATA[Fourier]]></category> <category><![CDATA[order domain]]></category> <category><![CDATA[orders]]></category> <category><![CDATA[revolution speed]]></category> <category><![CDATA[rotation angles]]></category> <category><![CDATA[shaft encoder]]></category> <category><![CDATA[synchronous]]></category> <category><![CDATA[synchronous data]]></category> <category><![CDATA[tachometer]]></category> <category><![CDATA[time domain]]></category> <category><![CDATA[vibration]]></category> <category><![CDATA[waterfall]]></category><guid
isPermaLink="false">http://blog.prosig.com/?p=2228</guid> <description><![CDATA[The term synchronous data is usually applied to vibration or acoustic data that is captured from an item of rotating equipment at regularly spaced angle intervals as distinct from regularly...]]></description> <wfw:commentRss>http://blog.prosig.com/2011/11/09/what-is-synchronous-angular-sampling/feed/</wfw:commentRss> <slash:comments>0</slash:comments> </item> <item><title>Video: Noise &amp; Vibration From Rotating Machines</title><link>http://blog.prosig.com/2011/10/04/video-how-to-analyze-noise-vibration-from-rotating-machinery/</link> <comments>http://blog.prosig.com/2011/10/04/video-how-to-analyze-noise-vibration-from-rotating-machinery/#comments</comments> <pubDate>Tue, 04 Oct 2011 08:25:33 +0000</pubDate> <dc:creator>Chris Mason</dc:creator> <category><![CDATA[signal processing]]></category> <category><![CDATA[videos]]></category> <category><![CDATA[FFT]]></category> <category><![CDATA[harmonics]]></category> <category><![CDATA[noise]]></category> <category><![CDATA[noise vibration]]></category> <category><![CDATA[orders]]></category> <category><![CDATA[rotating machinery]]></category> <category><![CDATA[speed]]></category> <category><![CDATA[tacho]]></category> <category><![CDATA[vibration]]></category> <category><![CDATA[waterfall]]></category><guid
isPermaLink="false">http://blog.prosig.com/?p=2514</guid> <description><![CDATA[This is complete version of the video illustrating my recent article How To Measure Noise &#38; Vibration In Rotating Machines. This video was previously published on the blog in 3 parts....]]></description> <wfw:commentRss>http://blog.prosig.com/2011/10/04/video-how-to-analyze-noise-vibration-from-rotating-machinery/feed/</wfw:commentRss> <slash:comments>0</slash:comments> </item> <item><title>How To Analyze Noise &amp; Vibration In Rotating Machines</title><link>http://blog.prosig.com/2011/08/09/how-to-measure-noise-vibration-in-rotating-machines/</link> <comments>http://blog.prosig.com/2011/08/09/how-to-measure-noise-vibration-in-rotating-machines/#comments</comments> <pubDate>Tue, 09 Aug 2011 09:07:54 +0000</pubDate> <dc:creator>Chris Mason</dc:creator> <category><![CDATA[popular]]></category> <category><![CDATA[signal processing]]></category> <category><![CDATA[acceleration]]></category> <category><![CDATA[bearings]]></category> <category><![CDATA[DATS]]></category> <category><![CDATA[excitation]]></category> <category><![CDATA[fatigue]]></category> <category><![CDATA[natural frequencies]]></category> <category><![CDATA[noise]]></category> <category><![CDATA[orders]]></category> <category><![CDATA[P8000]]></category> <category><![CDATA[refinement]]></category> <category><![CDATA[rotating machinery]]></category> <category><![CDATA[tacho]]></category> <category><![CDATA[tachometer]]></category> <category><![CDATA[torsional vibration]]></category> <category><![CDATA[transmission systems]]></category> <category><![CDATA[variable speed]]></category> <category><![CDATA[vibration]]></category> <category><![CDATA[vibration analysis]]></category> <category><![CDATA[waterfall]]></category><guid
isPermaLink="false">http://blog.prosig.com/?p=2170</guid> <description><![CDATA[In this article we will look at the basic steps behind a simple rotating machinery study. We won&#8217;t look in great detail at some of the techniques involved &#8211; we deal with...]]></description> <wfw:commentRss>http://blog.prosig.com/2011/08/09/how-to-measure-noise-vibration-in-rotating-machines/feed/</wfw:commentRss> <slash:comments>3</slash:comments> <enclosure
url="http://blog.prosig.com/wp-content/uploads/2011/07/noiseSignal.mp3" length="91844" type="audio/mpeg" /> </item> <item><title>Measurement And Analysis Of Torsional Vibration</title><link>http://blog.prosig.com/2008/10/17/measurement-and-analysis-of-torsional-vibration/</link> <comments>http://blog.prosig.com/2008/10/17/measurement-and-analysis-of-torsional-vibration/#comments</comments> <pubDate>Fri, 17 Oct 2008 07:44:13 +0000</pubDate> <dc:creator>Adrian Lincoln</dc:creator> <category><![CDATA[signal processing]]></category> <category><![CDATA[angle domain]]></category> <category><![CDATA[crankshaft]]></category> <category><![CDATA[gearbox]]></category> <category><![CDATA[nvh]]></category> <category><![CDATA[orders]]></category> <category><![CDATA[P8000]]></category> <category><![CDATA[powertrain]]></category> <category><![CDATA[pulse edge]]></category> <category><![CDATA[rotating machinery]]></category> <category><![CDATA[tacho]]></category> <category><![CDATA[tachometer]]></category> <category><![CDATA[torsional vibration]]></category> <category><![CDATA[vibration]]></category> <category><![CDATA[waterfall]]></category><guid
isPermaLink="false">http://blog.prosig.com/?p=103</guid> <description><![CDATA[Torsional vibration is of key importance in the area of vehicle development and refinement. The main contributory source is the engine where periodically occurring combustion cycles cause variation in the...]]></description> <wfw:commentRss>http://blog.prosig.com/2008/10/17/measurement-and-analysis-of-torsional-vibration/feed/</wfw:commentRss> <slash:comments>13</slash:comments> </item> <item><title>Vibration Monitoring Phase Measurement And The Tacho Signal</title><link>http://blog.prosig.com/2008/03/04/vibration-monitoring-phase-measurement-and-the-tacho-signal/</link> <comments>http://blog.prosig.com/2008/03/04/vibration-monitoring-phase-measurement-and-the-tacho-signal/#comments</comments> <pubDate>Tue, 04 Mar 2008 09:52:09 +0000</pubDate> <dc:creator>Dr Colin Mercer</dc:creator> <category><![CDATA[signal processing]]></category> <category><![CDATA[Fourier]]></category> <category><![CDATA[modulus]]></category> <category><![CDATA[orders]]></category> <category><![CDATA[phase]]></category> <category><![CDATA[rotating machinery]]></category> <category><![CDATA[speed signal]]></category> <category><![CDATA[tacho]]></category> <category><![CDATA[vibration]]></category><guid
isPermaLink="false">http://blog.prosig.com/2008/03/04/vibration-monitoring-phase-measurement-and-the-tacho-signal/</guid> <description><![CDATA[Any vibration signal may be analyzed into amplitude and phase as a function of frequency. The phase represents fifty percent of the information so it is most important to measure...]]></description> <wfw:commentRss>http://blog.prosig.com/2008/03/04/vibration-monitoring-phase-measurement-and-the-tacho-signal/feed/</wfw:commentRss> <slash:comments>5</slash:comments> </item> <item><title>Orders v Time – Comparing Overall Levels</title><link>http://blog.prosig.com/2007/10/23/orders-v-time-comparing-overall-levels/</link> <comments>http://blog.prosig.com/2007/10/23/orders-v-time-comparing-overall-levels/#comments</comments> <pubDate>Tue, 23 Oct 2007 13:33:06 +0000</pubDate> <dc:creator>Dr Colin Mercer</dc:creator> <category><![CDATA[signal processing]]></category> <category><![CDATA[Hanning]]></category> <category><![CDATA[hopping FFT]]></category> <category><![CDATA[nvh]]></category> <category><![CDATA[orders]]></category> <category><![CDATA[rotating machinery]]></category> <category><![CDATA[rundown]]></category> <category><![CDATA[runup]]></category><guid
isPermaLink="false">http://blog.prosig.com/2007/10/23/orders-v-time-comparing-overall-levels/</guid> <description><![CDATA[By combining a speed signal with a data signal and using the Short Time FFT algorithm (Hopping FFT), it is possible to extract order data directly as a function of...]]></description> <wfw:commentRss>http://blog.prosig.com/2007/10/23/orders-v-time-comparing-overall-levels/feed/</wfw:commentRss> <slash:comments>4</slash:comments> </item> <item><title>Sound Steering</title><link>http://blog.prosig.com/2007/09/12/sound-steering/</link> <comments>http://blog.prosig.com/2007/09/12/sound-steering/#comments</comments> <pubDate>Wed, 12 Sep 2007 09:54:20 +0000</pubDate> <dc:creator>Dr Colin Mercer</dc:creator> <category><![CDATA[applications]]></category> <category><![CDATA[signal processing]]></category> <category><![CDATA[acoustic]]></category> <category><![CDATA[automotive]]></category> <category><![CDATA[FFT]]></category> <category><![CDATA[microphone]]></category> <category><![CDATA[noise]]></category> <category><![CDATA[nvh]]></category> <category><![CDATA[orders]]></category> <category><![CDATA[pump]]></category> <category><![CDATA[Richard O'Sullivan]]></category> <category><![CDATA[runup]]></category> <category><![CDATA[steering pump]]></category> <category><![CDATA[waterfalls]]></category><guid
isPermaLink="false">http://prosig.com/blog/?p=3</guid> <description><![CDATA[The requirement was to develop a ‘standard’ test for assessing the sound quality of power steering pumps in vehicles. Measurements needed to be objective so that the method would be...]]></description> <wfw:commentRss>http://blog.prosig.com/2007/09/12/sound-steering/feed/</wfw:commentRss> <slash:comments>0</slash:comments> </item> <item><title>Measuring Torsional Crank Shaft Jitter</title><link>http://blog.prosig.com/2007/06/24/measuring-torsional-crank-shaft-jitter/</link> <comments>http://blog.prosig.com/2007/06/24/measuring-torsional-crank-shaft-jitter/#comments</comments> <pubDate>Sun, 24 Jun 2007 07:43:54 +0000</pubDate> <dc:creator>Chris Mason</dc:creator> <category><![CDATA[applications]]></category> <category><![CDATA[signal processing]]></category> <category><![CDATA[crankshaft]]></category> <category><![CDATA[jitter]]></category> <category><![CDATA[nvh]]></category> <category><![CDATA[orders]]></category> <category><![CDATA[rotating machinery]]></category> <category><![CDATA[tachometer]]></category> <category><![CDATA[torsional vibration]]></category> <category><![CDATA[vibration]]></category><guid
isPermaLink="false">http://blog.prosig.com/2007/11/19/measuring-torsional-crank-shaft-jitter/</guid> <description><![CDATA[Using Prosig’s P8000 series data acquisition system with DATS signal analysis software, torsional analysis (crank jitter) was performed on an automotive engine attached to an engine dynamometer. The significance of...]]></description> <wfw:commentRss>http://blog.prosig.com/2007/06/24/measuring-torsional-crank-shaft-jitter/feed/</wfw:commentRss> <slash:comments>0</slash:comments> </item> <item><title>Order Cuts And Overall Level</title><link>http://blog.prosig.com/2007/02/25/order-cuts-and-overall-level/</link> <comments>http://blog.prosig.com/2007/02/25/order-cuts-and-overall-level/#comments</comments> <pubDate>Sun, 25 Feb 2007 14:38:43 +0000</pubDate> <dc:creator>Dr Colin Mercer</dc:creator> <category><![CDATA[signal processing]]></category> <category><![CDATA[FFT]]></category> <category><![CDATA[nvh]]></category> <category><![CDATA[orders]]></category> <category><![CDATA[overall level]]></category> <category><![CDATA[rms]]></category> <category><![CDATA[waterfall]]></category><guid
isPermaLink="false">http://blog.prosig.com/2007/02/25/order-cuts-and-overall-level/</guid> <description><![CDATA[Order cuts are taken from a set of FFTs, each one at a different rpm. The rms level is then found as the Square root of the Sum of the...]]></description> <wfw:commentRss>http://blog.prosig.com/2007/02/25/order-cuts-and-overall-level/feed/</wfw:commentRss> <slash:comments>0</slash:comments> </item> <item><title>Exhaust Development Using A Prosig P8000 System</title><link>http://blog.prosig.com/2006/02/20/exhaust-development-using-a-prosig-p8000-system/</link> <comments>http://blog.prosig.com/2006/02/20/exhaust-development-using-a-prosig-p8000-system/#comments</comments> <pubDate>Mon, 20 Feb 2006 11:17:48 +0000</pubDate> <dc:creator>James Wren</dc:creator> <category><![CDATA[applications]]></category> <category><![CDATA[signal processing]]></category> <category><![CDATA[acoustic]]></category> <category><![CDATA[dynamometer]]></category> <category><![CDATA[exhaust]]></category> <category><![CDATA[microphone]]></category> <category><![CDATA[muffler]]></category> <category><![CDATA[noise]]></category> <category><![CDATA[nvh]]></category> <category><![CDATA[orders]]></category> <category><![CDATA[waterfall]]></category><guid
isPermaLink="false">http://blog.prosig.com/2006/02/20/exhaust-development-using-a-prosig-p8000-system/</guid> <description><![CDATA[The following note describes an application of the Prosig P8000/DATS system in the refinement of an automotive exhaust muffler design for a major after-market exhaust manufacturer in Europe. The particular...]]></description> <wfw:commentRss>http://blog.prosig.com/2006/02/20/exhaust-development-using-a-prosig-p8000-system/feed/</wfw:commentRss> <slash:comments>2</slash:comments> </item> <item><title>Torsional Vibration, Tacho Pulses And Aliasing</title><link>http://blog.prosig.com/2006/01/12/torsional-vibration-tacho-pulses-and-aliasing/</link> <comments>http://blog.prosig.com/2006/01/12/torsional-vibration-tacho-pulses-and-aliasing/#comments</comments> <pubDate>Thu, 12 Jan 2006 15:44:34 +0000</pubDate> <dc:creator>Dr Colin Mercer</dc:creator> <category><![CDATA[signal processing]]></category> <category><![CDATA[gears]]></category> <category><![CDATA[nvh]]></category> <category><![CDATA[orders]]></category> <category><![CDATA[rotating machinery]]></category> <category><![CDATA[runup]]></category> <category><![CDATA[shaft encoder]]></category> <category><![CDATA[shafts]]></category> <category><![CDATA[tachometer]]></category> <category><![CDATA[torsional vibration]]></category> <category><![CDATA[vibration]]></category> <category><![CDATA[waterfalls]]></category><guid
isPermaLink="false">http://blog.prosig.com/2006/01/12/torsional-vibration-tacho-pulses-and-aliasing/</guid> <description><![CDATA[With shafts, gears and the like, the general method of determining the rotational speed is to use some form of tachometer or shaft encoder. These give out a pulse at...]]></description> <wfw:commentRss>http://blog.prosig.com/2006/01/12/torsional-vibration-tacho-pulses-and-aliasing/feed/</wfw:commentRss> <slash:comments>3</slash:comments> </item> <item><title>Analyzing Shaft Twist And Repairing Damaged Tachos</title><link>http://blog.prosig.com/2005/10/19/analyzing-shaft-twist-and-repairing-damaged-tachos/</link> <comments>http://blog.prosig.com/2005/10/19/analyzing-shaft-twist-and-repairing-damaged-tachos/#comments</comments> <pubDate>Wed, 19 Oct 2005 09:22:40 +0000</pubDate> <dc:creator>Dr Colin Mercer</dc:creator> <category><![CDATA[applications]]></category> <category><![CDATA[signal processing]]></category> <category><![CDATA[Butterworth]]></category> <category><![CDATA[orders]]></category> <category><![CDATA[phaseless]]></category> <category><![CDATA[rotating machinery]]></category> <category><![CDATA[runup]]></category> <category><![CDATA[shaft]]></category> <category><![CDATA[shaft encoder]]></category> <category><![CDATA[tachometer]]></category> <category><![CDATA[torsional vibration]]></category> <category><![CDATA[vibration]]></category><guid
isPermaLink="false">http://blog.prosig.com/2005/10/19/analyzing-shaft-twist-and-repairing-damaged-tachos/</guid> <description><![CDATA[A shaft has been instrumented with two shaft encoders, one at each end. Each shaft encoder gives out a once/rev pulse and a 720 pulses/rev signal. Each signal was digitised...]]></description> <wfw:commentRss>http://blog.prosig.com/2005/10/19/analyzing-shaft-twist-and-repairing-damaged-tachos/feed/</wfw:commentRss> <slash:comments>1</slash:comments> </item> <item><title>A Simple Noise Test</title><link>http://blog.prosig.com/2005/08/26/a-simple-noise-test/</link> <comments>http://blog.prosig.com/2005/08/26/a-simple-noise-test/#comments</comments> <pubDate>Fri, 26 Aug 2005 19:53:35 +0000</pubDate> <dc:creator>James Wren</dc:creator> <category><![CDATA[applications]]></category> <category><![CDATA[accelerometer]]></category> <category><![CDATA[acoustic]]></category> <category><![CDATA[exhaust]]></category> <category><![CDATA[Formula Ford]]></category> <category><![CDATA[microphone]]></category> <category><![CDATA[muffler]]></category> <category><![CDATA[noise]]></category> <category><![CDATA[nvh]]></category> <category><![CDATA[orders]]></category> <category><![CDATA[runup]]></category> <category><![CDATA[tachometer]]></category> <category><![CDATA[vibration]]></category> <category><![CDATA[waterfall]]></category><guid
isPermaLink="false">http://blog.prosig.com/2005/08/26/a-simple-noise-test/</guid> <description><![CDATA[In a recent article we described how the Prosig P8000 hardware and DATS software had been used to help Dalmeny Racing diagnose a problem with an exhaust bracket on their...]]></description> <wfw:commentRss>http://blog.prosig.com/2005/08/26/a-simple-noise-test/feed/</wfw:commentRss> <slash:comments>2</slash:comments> </item> <item><title>Average Waterfalls Or Average Orders?</title><link>http://blog.prosig.com/2005/06/14/average-waterfalls-or-average-orders/</link> <comments>http://blog.prosig.com/2005/06/14/average-waterfalls-or-average-orders/#comments</comments> <pubDate>Tue, 14 Jun 2005 20:51:52 +0000</pubDate> <dc:creator>Dr Colin Mercer</dc:creator> <category><![CDATA[signal processing]]></category> <category><![CDATA[FFT]]></category> <category><![CDATA[Hanning]]></category> <category><![CDATA[nvh]]></category> <category><![CDATA[orders]]></category> <category><![CDATA[rotating machinery]]></category><guid
isPermaLink="false">http://blog.prosig.com/2005/06/14/average-waterfalls-or-average-orders/</guid> <description><![CDATA[One would expect that averaging waterfalls and then extracting orders would give the same result as extracting orders from individual waterfalls and then averaging them. This is not the case....]]></description> <wfw:commentRss>http://blog.prosig.com/2005/06/14/average-waterfalls-or-average-orders/feed/</wfw:commentRss> <slash:comments>0</slash:comments> </item> <item><title>Audio Equalisation Filter &amp; Parametric Filtering</title><link>http://blog.prosig.com/2005/05/17/audio-equalisation-filter-parametric-filtering/</link> <comments>http://blog.prosig.com/2005/05/17/audio-equalisation-filter-parametric-filtering/#comments</comments> <pubDate>Tue, 17 May 2005 14:14:20 +0000</pubDate> <dc:creator>Dr Colin Mercer</dc:creator> <category><![CDATA[signal processing]]></category> <category><![CDATA[acoustic]]></category> <category><![CDATA[Butterworth]]></category> <category><![CDATA[Chebyshev]]></category> <category><![CDATA[filter]]></category> <category><![CDATA[noise]]></category> <category><![CDATA[orders]]></category> <category><![CDATA[tachometer]]></category><guid
isPermaLink="false">http://blog.prosig.com/2005/05/17/audio-equalisation-filter-parametric-filtering/</guid> <description><![CDATA[When working with audio signals a common requirement is to be able to equalise, cut or boost various frequency bands. A large number of hardware devices on the market provide...]]></description> <wfw:commentRss>http://blog.prosig.com/2005/05/17/audio-equalisation-filter-parametric-filtering/feed/</wfw:commentRss> <slash:comments>0</slash:comments> </item> <item><title>Measuring Torsional Twist &amp; Vibration Along a Shaft or Through a Geartrain</title><link>http://blog.prosig.com/2002/05/15/torsional-vibration-example/</link> <comments>http://blog.prosig.com/2002/05/15/torsional-vibration-example/#comments</comments> <pubDate>Wed, 15 May 2002 10:10:09 +0000</pubDate> <dc:creator>Dr Colin Mercer</dc:creator> <category><![CDATA[applications]]></category> <category><![CDATA[signal processing]]></category> <category><![CDATA[engine]]></category> <category><![CDATA[gear]]></category> <category><![CDATA[nvh]]></category> <category><![CDATA[orders]]></category> <category><![CDATA[rotating machinery]]></category> <category><![CDATA[shaft]]></category> <category><![CDATA[shaft encoder]]></category> <category><![CDATA[tachometer]]></category> <category><![CDATA[torsional vibration]]></category> <category><![CDATA[twist]]></category> <category><![CDATA[vibration]]></category><guid
isPermaLink="false">http://blog.prosig.com/2002/05/15/torsional-vibration-example/</guid> <description><![CDATA[The measurement of the twist angle between two points along a shaft or through a gear train may be derived from a pair of tacho signals, one at each end...]]></description> <wfw:commentRss>http://blog.prosig.com/2002/05/15/torsional-vibration-example/feed/</wfw:commentRss> <slash:comments>3</slash:comments> </item> <item><title>Frequency, Hertz &amp; Orders</title><link>http://blog.prosig.com/2002/02/03/frequency-hertz-orders/</link> <comments>http://blog.prosig.com/2002/02/03/frequency-hertz-orders/#comments</comments> <pubDate>Sun, 03 Feb 2002 17:09:46 +0000</pubDate> <dc:creator>Dr Colin Mercer</dc:creator> <category><![CDATA[signal processing]]></category> <category><![CDATA[FFT]]></category> <category><![CDATA[Nyquist]]></category> <category><![CDATA[orders]]></category> <category><![CDATA[rotating machinery]]></category><guid
isPermaLink="false">http://blog.prosig.com/2002/02/03/frequency-hertz-orders/</guid> <description><![CDATA[The most common form of digitising data is to use a regular time based method. That is data is sampled at a constant rate specified as a number of samples/second....]]></description> <wfw:commentRss>http://blog.prosig.com/2002/02/03/frequency-hertz-orders/feed/</wfw:commentRss> <slash:comments>0</slash:comments> </item> </channel> </rss>
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