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Shaking Hard Drives Instead of Spinning?

Twyko64 writes "A UK startup called Dataslide aims to develop 'hard drives' made of oscillating sheets of LCD-screen-like material with piezo-electronic actuators and many, many read:write heads. A 'hard drive' could be the same size and shape as an LCD screen. I wrote a this piece on Techworld about it."

7 of 252 comments (clear)

  1. Piezoelectric by JaxWeb · · Score: 5, Informative

    I've recently being doing a report for Physics on the Piezoelectric effect, and it is really interesting thing.

    When you put a current through a piezoelectric material (e.g. Quartz), it vibrates. The oscillations are used to create sound in Ultrasound Transducers, and they are used in watches as a time measurement.

    Conversely, if you mechanically compress a piezoelectric crystal, a charge will occur at the edges. This is used in Ultrasound to detect sound waves, in guitar pickups, and even in those cigarette lighters in cars.

    You can read more about it at Wikipedia: http://en.wikipedia.org/wiki/Piezoelectric

    Just thought this might interest someone.

    --
    - Jax
    1. Re:Piezoelectric by ajlitt · · Score: 5, Informative

      Right. Except the bit about the car lighters. Car lighters have a spiral of bimetal (a clad strip of two metals with dissimilar thermal expansion characteristics, see inside an old mechanical thermostat) that heats up as a circuit is completed between the center pin (12V) and the housing of the lighter socket. When the bimetal reaches a certain temperature, the bimetal spring twists and releases the pushbutton mechanism of the lighter, breaking contact with the 12V pin.

      Piezoelectrics are used in grill ignitors and 'electronic' lighters. They all use the same principle: Basically a piezoelectric material is put at the business end of a small hammer mechanism (much like a center punch) that strikes after a certain amount of pressure is applied at the button. Since the voltage at the edges of a piezoelectric material is proportional to the change in pressure, the quick blow produces a high voltage spike. That spike is fairly low current, but above the breakdown voltage of the air between the two contacts in the igniter.

      Interestingly, these lighter modules are great fun for zapping people. Since it's a low current, there's really no danger to using these. It's much like a static shock.

      One nifty application is in electronic buzzers. While that in itself may not be very inspirational, the actual design is pretty slick. Many fixed-frequency buzzers use a piezo elememt that has a small 'island' in the conductor along one pole. That island of conductive material is connected to a third wire. This wire is used as feedback to the oscillator driving the buzzer. What happens here is that you have the speaker (the majority of the element) and a separate microphone in the same substrate, enabling you to get a consistent tone by forcing feedback through the element itself! Since the peak volume of the buzzer is achieved at the resonating frequency of the element, this scheme locks the buzzer to the loudest tone it is designed to emit without any tuning of any sort.



      Also, check out some info on the 'net on the use of piezoelectrics in: SAW filters (surface acoustic wave), fuel injectors, crystal oscillators (not just for your Timex!), angular rate gyros, and micromanipulators such as scanning tunneling microscope heads.

  2. Bubble memory by Anonymous Coward · · Score: 1, Informative

    So, if I can take a guess here, they're moving the data instead of the heads? Like bubble memory from ~25 years ago?
    (Ouch, I feel old now. I still have an Intel eval kit lying around)

  3. An engineer by flowerp · · Score: 5, Informative


    The signal processing done to the analog signal from one read/write head is tremendous. The performance of modern hard drive comes from the signal detection algorithms and advanced error correction that is performed.

    You simply cannot do this at low cost when you have got several thousand or million r/w heads.

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    --- Eat my sig.
  4. Not so crazy by Anonymous Coward · · Score: 2, Informative

    The idea isn't that crazy but don't hold your breath waiting to see it actually work either. This idea is a lot closer to pure research than it is to technical implementation.

    If you can change the vibration of individual molecules, you could end up with very high storage densities. I can think of lots of reasons why this wouldn't work but the promise is immense.

    While I appreciate the reference to "The Innovator's Dilemma", I think it is a complete red herring. This isn't going to be a 'disruptive technology' for a long time if ever.

  5. Re:It's interesting, but won't improve anything. by HidingMyName · · Score: 2, Informative

    Greg Ganger and the folks at CMU have worked on sled based MEMS storage devices which use nanotechnology combined with improved materials for higher density electromagnetic storage (like how hard disks work, except the media is on a moving sled). In Ganger's case they explored head motion but decided against it as the area required for equipment to move the heads exceeded the heads range of motion, resulting in reduced storage capacity.

  6. first MEMS-based drive? by sloth+jr · · Score: 2, Informative

    For a background on the technology, check out:
    http://yogi.pdl.cmu.edu/research/MEMS/

    quote: "storage capacity of 1-10 GB of data in under 1 cm^2 area with access times of under a millisecond and streaming bandwidths of over 50 Mbytes per second."

    The research is about 5 years old. Because of constant seek times (the surface agitates in both x and y axes) and a kajillion heads, this is technology really designed to bridge EEPROM versus hard drive access times/throughput.

    Think 50 Mbytes per second isn't any great shakes? Keep in mind that this is a chip less than a square centimeter in area, and start thinking of replacing RAID drives with these.

    sloth jr