Every structure has a ?fundamental or natural frequency that it vibrates at in the absence of an outside force, which is just an everyday property of that particular physical system. 

The motion of non-motion is pretty hard to detect, however. Usually, engineers hunt out structural deformations and vibrations using lasers and accelerometers. Both of these methods are expensive and time-consuming: a single high-precision accelerometer can go for $1,000 and it takes a whole lot of them to do the job.

It'd be nice to be able to monitor these movements with just a camera, which is what a recent algorithm developed by engineers at MIT offers. The technique, which is described in ?a recent paper published in the Journal of Sound and Vibration, takes high-speed video of a given structure and decomposes it frame by frame, assigning each one a different frequency of motion. The effect of this is to greatly exaggerate subpixel motions within a target region of pixels. The results can be seen above.