Question regarding HDD motor

[fezder]

Right, i'm doing that project some of you must have seen, clock/similar on computer HDD. Right now problem is quite simple: that HDD won't run all the time, shuts down after a while. I have a feeling it is meant to be that way if no data is read/attempted to read, as i took that reading-arm totally off just because it would get in way in project

What i do know of that HDD motor is that it's now even stepper motor, but 3-phase BLDC, so if i must design that controller for it, well, it must be done but if you guys would know any easier way to fool to keep it spinning, thanks a bunch! or even better learning wise, point me in right direction/give hint

 

[alec_t]

that project some of you must have seen

If you provide a link we might have a clue as to which project .

 

[fezder]

i was quite sure i placed that link! seems i didnt....there are many variations but here's one
**broken link removed**

As far as i can see and read, he didn't make anything on HDD motherboard/controller

 

[fezder]

ehh, i possibly placed wrong link, but this i based on earlier link i provided
http://www.ian.org/HD-Clock/

 

[ronv]

Right, i'm doing that project some of you must have seen, clock/similar on computer HDD. Right now problem is quite simple: that HDD won't run all the time, shuts down after a while. I have a feeling it is meant to be that way if no data is read/attempted to read, as i took that reading-arm totally off just because it would get in way in project

What i do know of that HDD motor is that it's now even stepper motor, but 3-phase BLDC, so if i must design that controller for it, well, it must be done but if you guys would know any easier way to fool to keep it spinning, thanks a bunch! or even better learning wise, point me in right direction/give hint

If I remember correctly most drives want to lock to the sector data on the disk. So they spin up then lock to data.

 

[fezder]

I'm getting an rc-controller today from my buddy, it should spin that motor just fine.....BUT, i'm still interested whether it's possible to hack hdd motor without external controller

 

[jpanhalt]

BUT, i'm still interested whether it's possible to hack hdd motor without external controller

Here's an instructable using a HDD: https://www.instructables.com/id/BLDC-Motor-Control-with-Arduino-salvaged-HD-motor/step4/The-Motor/

Given the cost of low-power BLDC controllers for models, I think that approach will not only be the easiest, but it will be the cheapest too. That instructable as well as many other sources describe what is required.

John

 

[fezder]

and due the fact i've never builded 3-phase bridge, who knows how many fets/transistors i'll blow up before actually getting the hang of building BLDC controllers? so yeah, perhaps this time would be better to stick at ready-made models which start from around 5€ (20amp versions)

 

[large_ghostman]

Older HDD seem better for this, some of the newer ones I have tried seem to have a cut out like you described. I tend to just cut the connections to the control board and use a dedicated chip or whatever is at hand

 

[fezder]

I borrowed an RC-brushless controller from buddy, it does the trick well enough. Now i need ''only'' to write more code for arduino and place sensor (either hall effect or ir sensor) to call it home...and i should get this project up'n running till friday, but at least somewhat ready! luckily i have basic stuff understood: arduin calculates angles from rpm and lights LED's in correct timing and refreshes at each ''home''

 

[large_ghostman]

long time since I did mine but from memory I went with a small black bit of tape on the back of the HDD plate and just reflected IR, so every time the plate past the black tape it would trigger an interrupt. I used a pic, I was given a large arduino kit for Christmas and its still unpacked. I have used sil labs 8051 and there 32 bit range and pics, the thought of learning yet another platform dosnt do it for me .
I have a few old drives I might look at the boards and see where the differences are, I know the very very old HDD are really easy to spin up.

 

[fezder]

Video of suceess thanks ETO guys!

 

[large_ghostman]

Nice one, I am glad you got it running ok.

 

[fezder]

hehe, now i just need to figure out how do i automatize it....not for full speed but say 70hz

 

[jpanhalt]

What speed (rpm) is the drive rated for?

John

 

[dr pepper]

Ron mentioned the disk, later drives have servo data on the disk, without it, as in you have pulled the whole thing apart the drive wont run for long, either that or it was some power saving thingy.
The rc esc was agood idea.
Watch out for the disk exploding at that speed, I think thats what jp was eluding too.

 

[fezder]

What speed (rpm) is the drive rated for?

hmm, i have sadly no idea but it was either 5k or 7k

Watch out for the disk exploding at that speed, I think thats what jp was eluding too

yeah, i read that too after i tested it for 12k....luckily it didn't shatter, but i never even thought these could explode
but for illusion even around 4k is enough, won't be that noisy either

 

[jpanhalt]

Yes, I would definitely "elude" an exploding anything.

And yes, 70 Hz being 4200 rpm is why I asked the question. Even 60 Hz will probably suffice for POV. Some people will be able to see the flicker, particularly in their peripheral vision.

John

 

[fezder]

i already had interesting moment when i placed 4mm nut as balance when i earlier used hall-sensor to detect rounds....well of course that nut went nuts so to say....and i do use satefy glasses just in case!