"When the computer is stable, the drive operates normally again."
So unless you install a drive that has its own motion detection on board the computer will simply quickly 'park' the drive and will allow it to resume operation without any issues when it has landed.
I used it to add X11 autorotation to an X61 tablet. No spin animation, but it was a cool one-day hack nonetheless.
The fun part was that the orientation analyses was done from a shell script, and actually worked 100% of the time (unlike so many phones)! \o/
The insane part was that DRM/KMS on Linux is 1000% crazy and I had to patch the kernel to stop poking the backlight on every. rotation. event, grr. (I had to do it in the kernel - I basically killed DPMS - because X11 libdrm is utterly incomprehensible.)
Could built-in protections like this in harddrives be a sufficient protection in an earthquake? What other moving parts are that at risk here? Assuming the servers themselves are locked in cages, I wouldn't expect them to crash to the floor.
Although the big difference here is it's not a sudden drop but a prolonged forceful shaking.