The car makers use two kinds of active noise reduction. One is the injection of inverse waves into the car's stereo, to reduce road noise and body panel vibration. This is controlled by a microphone in the cabin (probably the same one used for hands-free phone calls).
The other one is in the engine mounts, where they have a liquid inside the rubber mount that can stiffen up on command (maybe magnetorheological[1], maybe some other kind), and this is used to counteract the vibrations the engine would transmit to the body/chassis. This is controlled by the ECU because it knows when the engine is on a power stroke and can thus apply correction on a timing basis.
I would think the latter would be what the MRI makers would want to investigate -- they've got a huge spinning mass[2] with components that vibrate. Much like an engine. :)
The other one is in the engine mounts, where they have a liquid inside the rubber mount that can stiffen up on command (maybe magnetorheological[1], maybe some other kind), and this is used to counteract the vibrations the engine would transmit to the body/chassis. This is controlled by the ECU because it knows when the engine is on a power stroke and can thus apply correction on a timing basis.
I would think the latter would be what the MRI makers would want to investigate -- they've got a huge spinning mass[2] with components that vibrate. Much like an engine. :)
[1] http://en.wikipedia.org/wiki/Magnetorheological_damper
[2] At work, so can't post a video link, but if you look for "cover off mri" it's really scary/impressive how they work.