In normal circumstances seeing vibration means one of X number of things: The machine is at a late stage of failure and you might want to take cover, the vibration is on a large structure, or you’re looking at an ODS wire frame animation. 

With the introduction of Motion Amplification technology – researched and developed by Jeff Hay of RDI Technologies while a PhD graduate at Kentucky State University – visualising vibration has taken a new turn. In fact I believe that, broadly speaking, vibration analysis for industrial applications has changed irreversibly for the better.

When a vibration analyst collects data from a machine and finds a low frequency fault, they immediately try to understand what the spectra and time waveform is telling them. In their mind’s eye, picturing or visualising how the vibration is acting upon the machine, how the vibration would look in slow motion and exaggerated form, particularly so when troubleshooting a known issue using phase analysis. 

Complex ideas it’s seems are better interpreted through the use of imagery, visually through pictures – ‘a picture paints a thousand words’ as they say. So, mankind’s first languages from over 5000 years ago conveyed their complex ideas, concepts, thoughts and spoken words in pictorial form and, with traditional Chinese remaining fundamentally unchanged for around 3000 years, you can easily see the benefit of a pictoral written language conveying a lot of information in a simple, succinct way.

How do we make things simple for a child to learn? Show them a picture, a photograph, a video, make a charade-like gesture and teach them from the simplest form of description – a visual aid. 

This simple visualisation is now being applied to complex vibration data. Operation Deflecting Shape or ODS studies aim to do just that, collecting as many vibration data points as feasibly possible and converting this numerical, graphical data into a wire-framed animation – why? To understand a complex machine issue in a simple, visual form. This has served industry well for many years and will continue to do so, but there are limiting factors to the technique – high cost per point, more vibration points equals more sensors equals more cost. The activity becomes more labour intensive and more time-consuming during setup, acquisition and processing. At the end of it what do you get? A wire-frame animation. So what if you could just see the real thing?

Hay’s Motion Amplification does just that. By engineering camera pixels to enable vibration data collection in much the same way as a traditional accelerometer does, Hay has successfully created a technology that can visualise vibration data in near real-time video format. The technique uses no physical contact to measure, it is purely optical making it usable on an ever-growing list of applications and materials. Packaged as RDI’s Iris M system the whole acquisition and analysis can be as short as 10 minutes.

Accurately measuring discrete frequencies and amplitudes over the course of a video acquisition, the system then allows the analyst to exaggerate or ‘amplify’ the measured motion. The algorithms amplify the measured values linearly across all the frame, so if there’s no vibration there is no motion in the video even when there is vibration elsewhere in the video. This means if you are looking at some pipework with 2mm/s and you amplify it to see the motion, a solid concrete floor doesn’t start moving too. Interestingly, the technique does enhance differentials of levels and/or frequencies particularly well such as very low levels of unbalance on rotating machines. 

RDI’s Iris M with Motion Amplification is available from UK distributor Reliability Maintenance Solutions which has a YouTube channel that is frequently updated with new videos: xxxxx