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Shielding An HD From Excessive Vibrations?

Posted by Cliff on from the bass-fo'-yo'-face-but-not-fo'-yo'-platters dept.

schematic asks: "I'm planning on building an mp3 player for my car, but a few of my buddies brought up a good point yesterday. They asked how I'd planned to mount the hard drive to protect it from vibrations (bass) and bumps (crazy driving). I've heard of a few good ideas, but I dont know what I can do to shield it from the bass, since that seems to shake the daylights outta everything. Anyone have a similar setup or an idea that works?"

2 of 37 comments (clear)

  1. Vibrational modes by adipocere · · Score: 3
    Your first step is to identify your vibrational modes. For example:
    • Subwoofer: Assume that you will be protecting against 10 Hz to perhaps 100 Hz
    • Random shocks: No guess as to the frequency of these.
    • Figuring out the direction of these vibrations is important. Will they be going from side to side? Up and down? Front to back?
    Examine the materials that came with your hard drive. Many of them will talk about what kinds of vibrational modes they are rated for, what they can withstand, etc. Compare to the directions of your vibrational modes to find in which to mount your hard drive. That is, if your vibrations are mostly side-to-side, mount your hard drive such that your most vulnerable direction (for example, perpendicular to the platters) is not parallel to the side-to-side vibration.

    Now, another important part is that you want to damp the vibrations in multiple modes. That is, you want to guard against as many big modes as possible. If you have a contraption made from bungee cords, it will damp best against a specific frequency (and possibly some harmonics), but the damping will be less effective at other frequencies. Where the weak patches are, damp with a different material. So, perhaps bungee cords + silicone gel + foam could guard against many of them.

    Test. Test again. If I were you, I would construct a "cradle" for the drive or case. Then, put something in it susceptible to vibration (a covered bowl of water, perhaps, or a leaf). Crank the bass. Have someone else drive around while you look at it. See any ripples or shaking? If so, back to the drawing board! More high-tech solutions exist for testing, etc., but I doubt you want to go there.

    And, when all else fails, drivespace is cheap. Buy several replacement drives.

  2. Re:What about temperature extremes? by djweis · · Score: 3

    I don't worry too much about vibration for mine. I have it in a case in my trunk. Once my dsl comes back up, you can see it here.