Harddisk motion detection?

Is it possible that inside certain harddisks motion detectors are placed?
I have a harddsk which works fine but as soon you move the drive (powered on
and connected to pc)
the head sounds as it wants to go in park, if i leave the drive alone it
just works fine.
IDE and power cable are ok.
Not relevant for a repair but plain curiosity, i would expect it on a laptop
disk but not a desktop.

Bart Bervoets

On Tue, 03 Oct 2006 15:05:22 +0200, Bart Bervoets Has Frothed:

> Is it possible that inside certain harddisks motion detectors are placed?
> I have a harddsk which works fine but as soon you move the drive (powered
> on and connected to pc)
> the head sounds as it wants to go in park, if i leave the drive alone it
> just works fine.
> IDE and power cable are ok.
> Not relevant for a repair but plain curiosity, i would expect it on a
> laptop disk but not a desktop.
>
> Bart Bervoets

I can safely say that no modern drive has any such thing.


--
Pierre Salinger Memorial Hook, Line & Sinker, June 2004

COOSN-266-06-25794

Meat Plow <(E-Mail Removed)> writes:

> On Tue, 03 Oct 2006 15:05:22 +0200, Bart Bervoets Has Frothed:
>
> > Is it possible that inside certain harddisks motion detectors are placed?
> > I have a harddsk which works fine but as soon you move the drive (powered
> > on and connected to pc)
> > the head sounds as it wants to go in park, if i leave the drive alone it
> > just works fine.
> > IDE and power cable are ok.
> > Not relevant for a repair but plain curiosity, i would expect it on a
> > laptop disk but not a desktop.
> >
> > Bart Bervoets
>
> I can safely say that no modern drive has any such thing.

Some laptops and external harddrives for laptops do have shock detectors but
I don't know if they are inside the drives.

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Bart Bervoets wrote:
> Is it possible that inside certain harddisks motion detectors are placed?
> I have a harddsk which works fine but as soon you move the drive (powered on
> and connected to pc)
> the head sounds as it wants to go in park, if i leave the drive alone it
> just works fine.
> IDE and power cable are ok.
> Not relevant for a repair but plain curiosity, i would expect it on a laptop
> disk but not a desktop.
>
> Bart Bervoets
>
>
You should never move a running drive. It could crash.

--

50% of all statistics are wrong. The rest don't matter.


Clyde Crashcup

On Tue, 03 Oct 2006 15:24:23 +0000, Clyde Crashcup Has Frothed:

> Bart Bervoets wrote:
>> Is it possible that inside certain harddisks motion detectors are
>> placed? I have a harddsk which works fine but as soon you move the drive
>> (powered on and connected to pc)
>> the head sounds as it wants to go in park, if i leave the drive alone it
>> just works fine.
>> IDE and power cable are ok.
>> Not relevant for a repair but plain curiosity, i would expect it on a
>> laptop disk but not a desktop.
>>
>> Bart Bervoets
>>
>>
> You should never move a running drive. It could crash.

LOL that made me laugh.


--
Pierre Salinger Memorial Hook, Line & Sinker, June 2004

COOSN-266-06-25794

Meat Plow spake thus:

> On Tue, 03 Oct 2006 15:24:23 +0000, Clyde Crashcup Has Frothed:
>
>>Bart Bervoets wrote:
>>
>>>Is it possible that inside certain harddisks motion detectors are
>>>placed? I have a harddsk which works fine but as soon you move the drive
>>>(powered on and connected to pc)
>>>the head sounds as it wants to go in park, if i leave the drive alone it
>>>just works fine.
>>>IDE and power cable are ok.
>>>Not relevant for a repair but plain curiosity, i would expect it on a
>>>laptop disk but not a desktop.
>>
>>You should never move a running drive. It could crash.
>
> LOL that made me laugh.

Yeah, I guess all those people using laptops must just *imagine* they're
moving their computer while it's on.


--
Save the Planet
Kill Yourself

- motto of the Church of Euthanasia (http://www.churchofeuthanasia.org/)

Bart Bervoets wrote:
> Is it possible that inside certain harddisks motion detectors are placed?
> I have a harddsk which works fine but as soon you move the drive (powered on
> and connected to pc)
> the head sounds as it wants to go in park, if i leave the drive alone it
> just works fine.
> IDE and power cable are ok.
> Not relevant for a repair but plain curiosity, i would expect it on a laptop
> disk but not a desktop.
>
> Bart Bervoets
>
>


Most microdrives have this feature, but these are the tiny drives the
size of CF cards used in many portable music players. Just moving it
should not trigger it though, it takes a fair bit of shock.

Hi!

> Is it possible that inside certain harddisks motion detectors are placed?

Anything is always possible. But I doubt that there is any such thing in a
desktop hard drive. Laptop drives may have such circuitry in place.

Based on some drives that I've worked with over time, I'd say what you're
seeing is likely a result of the spindle motor somehow changing speed
slightly as you move it. The drive's controlling electronics can monitor the
RPM of this motor and may shut the drive down if enough of a change is
detected. The motor may be getting ready to fail or it may have worn
bearings that allow a significant RPM change when you move it.

You can get most desktop drives to reinitialize themselves with a mild tap.
I don't suggest trying that on a drive you depend upon. And while it
generally does no harm to move a running hard drive, you should be careful
not to drop, jar, shake or abuse it while it is running. If any one of those
things were to happen while the drive was running, a head crash or other
drive failure is possible.

William

"William R. Walsh" <(E-Mail Removed) m>
wrote in message news:ceIUg.89757$aJ.137@attbi_s21...

> You can get most desktop drives to reinitialize themselves with a mild
> tap.
> I don't suggest trying that on a drive you depend upon. And while it
> generally does no harm to move a running hard drive, you should be careful
> not to drop, jar, shake or abuse it while it is running. If any one of
> those
> things were to happen while the drive was running, a head crash or other
> drive failure is possible.

One notorious 10 Mb hard drive Radio Shack sold would only start after a
weekend if you first dropped it about a foot onto a desk!

"Homer J Simpson" <(E-Mail Removed)> wrote in message
news:JCIUg.50909$E67.45445@clgrps13...

> One notorious 10 Mb hard drive Radio Shack sold would only start after a
> weekend if you first dropped it about a foot onto a desk!

I've seen many, many drives like that- it's called 'stiction'. The heads and
platters are so perfectly formed and smooth that they can bond together
preventing the drive motor spinning up the platters. Usually the motor can
be heard pulsing and giving up after a few tries. The best way to release
the heads from the platters is IME to hold the drive and quickly flick it in
a rotational plane to spin the internal platters breaking the bond. Freezing
the drive overnight can also do the trick, but the drive must be put in a
completely sealed bag beforehand. Warming with a hairdryer can also help.
Thumping the drive onto a hard surface should be a last resort.

Stiction is not usually an issue on modern drives, but it was common on the
old MFM/RLL/ESDI style drives.

Dave