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Cringely's Shameless Self-Promotion

Zonk posted more than 7 years ago | from the buy-the-cringely-t-shirt dept.

225

wild_berry writes "The latest edition of Bob Cringely's column at pbs.org, entitled Shameless Self-Promotion: Bob's Disk Drive is up. He's talking about replacing the glass or metal platters in present hard disk drives with foil platters in order to save energy." From the article: "The materials cost more but we use so much less of it (the disk is so incredibly thin) that the total material cost is substantially less. This 'floppy' material has the same kind of magnetic coatings used on standard disk drives and our drives live on the same technology growth curve as those others. The way we obtain greater storage density is simply by putting more platters in a drive (say 12-15 instead of 4-5 in an enterprise 3.5-inch drive) because they are much thinner and can be stacked closer together. The only parts of the drive that are significantly different are the platters and the heads and the heads vary only in having an extra slot."

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225 comments

Quick... (5, Funny)

Anonymous Coward | more than 7 years ago | (#16609340)

Get out the tin foil...umm.. okay, it's alrealdy in there

Too floppy (2, Insightful)

the_povinator (936048) | more than 7 years ago | (#16609342)

I should read the FA, but what's to stop his platters from flopping all over the place?

just spin them all the time (1)

krell (896769) | more than 7 years ago | (#16609410)

"I should read the FA, but what's to stop his platters from flopping all over the place?"

Just keep 'em spinning all the time to keep them in a nice flat disc.

Floppy films held rigid by spin have a fatal flaw. (0)

Anonymous Coward | more than 7 years ago | (#16609544)

Okay, now with them spinning, rotate the drive around an axis other than the spin axis of the discs...

The Gyroscope Effect (1)

krell (896769) | more than 7 years ago | (#16609580)

"Okay, now with them spinning, rotate the drive around an axis other than the spin axis of the discs..."

And???? Due to the significantly decreased mass of the platters, isn't this much less of a problem now?

Re:The Gyroscope Effect (2, Insightful)

jcr (53032) | more than 7 years ago | (#16609800)

The heads only have to touch the film a few times before the emulsion is history.

We use glass because it's dimensionally stable, easy to make extremely flat, and it's about as rigid as you could want it to be, regardless of whether the disk is spun up or not.

-jcr

Re:The Gyroscope Effect (2, Informative)

drakaan (688386) | more than 7 years ago | (#16610152)

Just read the article then...there are a few patents involved, and a few engineers who already have globally-used patents on things like drive heads. There was mention of the head setup maintaining an air cushion (which is a lot easier with a less-rigid platter) and of the design keeping dust away from the gap, meaning assembly doesn't require traditional clean-room techniques.

The article is admittedly short on specifics, but I imagine they'll be forthcoming, since he also mentioned that we'd actually be seeing the drives from numerous manufacturers next year.

If they managed to prove the tech to drive manufacturers, I'd imagine the dimensional stability of glass didn't trump the tech they're introducing.

Re:The Gyroscope Effect (1)

hcob$ (766699) | more than 7 years ago | (#16609946)

Yes, it's decreased mass. But also a loss of rigidity. When you twist a floppy gyroscope quickly on it's axis, it's going to deform and cause a head crash...

btw an answer to the sig: I was at Ardis Hall drinking wine with Noman.

Re:The Gyroscope Effect (4, Informative)

drakaan (688386) | more than 7 years ago | (#16610230)

two words from the article: "air cushion" apply deductive reasoning as to how much more those two words matter when coupled with a flexible platter. There's actually plenty to read in the article, and I have lots of specific questions, but shock scenarios were something that cringley specifically addressed (like not having to park the heads or use "uh-oh" sensors to detect imminent shock, etc).

Not sure who the multiple HDD vendors are that will be introducing it next year, but I'm sure they asked a lot of questions about that, too.

Re:just spin them all the time (1)

Hijacked Public (999535) | more than 7 years ago | (#16609648)

I would assume that means they have to be powered 100% of the time, which would keep them out of a whole lot of applications.

Re:just spin them all the time (1)

rHBa (976986) | more than 7 years ago | (#16609888)

Spinning all the time would add to the power consumption of the disk (although it may still offer an advantage over heavier materials) but what about when the unit is switched off (during shipping for example) wouldn't it be easy for the platters to touch the heads and damage themselves?

Re:just spin them all the time (4, Funny)

drinkypoo (153816) | more than 7 years ago | (#16610470)

You can assume whatever you want but the article repeatedly mentions that they can be spun down, and that their spin-up time is less than a half a second (at least for small drives) to be read. Making assumptions when the FA is there for you to R makes an ass out of you, and umption.

Centrifugal force (5, Informative)

Xocet_00 (635069) | more than 7 years ago | (#16609420)

Ideally, the disks would be spinning so quickly that the outward force would keep them almost perfectly flat. Assuming the disks were very smooth and the internal atmosphere of the drive is gas-only (no dust - a safe assumption) there would hopefully be very little turbulence within the drive to cause fluctuations in the flatness of each platter.

In my lab we coat floppy materials (like plastic) in a spin coater at several thousand RPM. At that speed the disk may aswell be rigid.

Re:Centrifugal force (2, Interesting)

91degrees (207121) | more than 7 years ago | (#16609604)

Assuming the disks were very smooth and the internal atmosphere of the drive is gas-only (no dust - a safe assumption)

From the article: "the nature of our flying heads is such that dust is sucked away from the head-disk interface, meaning the drives do not have to be assembled in a clean room.". So presumably any dust that does drift onto the platter simply doesn't cause enough of a turbulance problem.

Re:Centrifugal force (2, Interesting)

attonitus (533238) | more than 7 years ago | (#16610008)

Turbulence isn't created by dust, it's a feature of the non-linearity of the Navier Stokes equations.

The arm holding the read/write head sits in the middle of what would otherwise be a nicely rotating flow between the platters. The Reynolds number for flow between platters in a disk drive is going to be something like 30 m/s * 0.001 m / 2E-5 m^2/s = 1500 >> 1, so vortices will be shed off the back of the arm. Which basically means turbulence.

Incidentally, this is currently one of the limits to increasing disk drive performance per watt. The arm also creates drag, which you'd like to minimise. To do that, you make the arm as thin as possible. However, the thinner you make it, the less stiff it is. Too thin and it will deform too much because of the vortex shedding and get too close to the platters.

Re:Centrifugal force (1)

attonitus (533238) | more than 7 years ago | (#16610254)

... and, now that I've read the article more carefully, it seems like what Cringely's talking about solves that problem in a novel way. Rather than fighting the fluid dynamics (by making the arm stiffer), it seems that they exploit it:

"...the flexible metal foil yields to the head, pushed away by a layer of compressed air, rather than being struck by it."

My guess is that, at least for data centre applications, the power saving he claims for this design does not come from the lower mass of the platters (which would only matter if you're spinning up and down a lot), but from the decreased drag due to smaller arms.

Re:Centrifugal force (2, Informative)

drinkypoo (153816) | more than 7 years ago | (#16610512)

Assuming the disks were very smooth and the internal atmosphere of the drive is gas-only (no dust - a safe assumption)

Uh no, not a safe assumption. Unless you can protect it from all corrosion - clearly not possible - then the interior of the device will actually produce dust... especially since there's a bunch of moving parts.

Re:Too floppy (2, Informative)

AKAImBatman (238306) | more than 7 years ago | (#16609452)

I should read the FA, but what's to stop his platters from flopping all over the place?

According to TFA, they'd use extremely strong materials like Stainless Steel or Titanium to ensure the rigidity of the disks. They claim that this would be just as shock resistant as a Flash drive, but with faster seek time. (i.e. the lighter weight would mean less inertia to fight against)

Re:Too floppy (2, Interesting)

ePhil_One (634771) | more than 7 years ago | (#16609494)

What about gyroscopic forces? turn the drive 90 degrees and teh spinning disks will want to turn a different way. Light weight helps reduce this, but it sstill must be strong enough not to shear itself off the spindle....

Re:Too floppy (3, Funny)

AKAImBatman (238306) | more than 7 years ago | (#16609612)

it sstill must be strong enough not to shear itself off the spindle....

*ahem*

According to TFA, they'd use extremely strong materials like Stainless Steel or Titanium to ensure the rigidity of the disks. They claim that this would be just as shock resistant as a Flash drive, but with faster seek time. (i.e. the lighter weight would mean less inertia to fight against)

Re:Too floppy (1)

gEvil (beta) (945888) | more than 7 years ago | (#16609630)

Yes, but what about gyroscopic forces? :-p

Re:Too floppy (3, Funny)

AKAImBatman (238306) | more than 7 years ago | (#16609674)

Yes, but what about gyroscopic forces?

I'm not sure. Did I mention that they'll use the strength of Titanium or Stainless Steel to ensure rigidity similar to that of thicker aluminum or glass platters?

*snap*

I knew I forget something. :P

Re:Too floppy (1)

Hoi Polloi (522990) | more than 7 years ago | (#16610386)

According to TFA they actually exploit the fact that the foil is NOT as rigid as current platters to actually decrease head crashes. The foil would flex away from the air cushioning created by the head.

Re:Too floppy (1)

AKAImBatman (238306) | more than 7 years ago | (#16610514)

According to TFA they actually exploit the fact that the foil is NOT as rigid as current platters to actually decrease head crashes.

Indeed. The idea is that it will be able to "give" a little to prevent crashes, while still being strong/rigid enough not to shear off from gyroscopic forces. If one platter were to actually fold into another (or worse, the casing) at >10,000 RPM, then lots of bad things would happen to the poor drive.

Re:Too floppy (1)

Dun Malg (230075) | more than 7 years ago | (#16609692)

According to TFA, they'd use extremely strong materials like Stainless Steel or Titanium to ensure the rigidity of the disks.

Re:Too floppy (1)

daBass (56811) | more than 7 years ago | (#16609756)

Ever taken apart a 3.5" floppy? How "floppy" is that disk really? I assume this will be much the same...

Flimsier disks & MTBF? (4, Insightful)

Orange Crush (934731) | more than 7 years ago | (#16609362)

The materials cost more but we use so much less of it (the disk is so incredibly thin) that the total material cost is substantially less.

And what do these thinner materials and more closely-spaced heads do for the MTBF and error rate in such drives?

Re:Flimsier disks & MTBF? (1)

Mr Pippin (659094) | more than 7 years ago | (#16609450)

And don't these extra heads cost money, too? Hmmmmm. Wait, All those extra heads need transceivers, etc. No, I don't see this costing less.

Re:Flimsier disks & MTBF? (2, Funny)

TopShelf (92521) | more than 7 years ago | (#16609704)

Don't forget the benefits from recycling all those old floppy disk jokes, though - the comedic savings to society as a whole would be huge...

Re:Flimsier disks & MTBF? (2, Insightful)

Jeff DeMaagd (2015) | more than 7 years ago | (#16609730)

Part of the reasons the current material is as thick as it is, is so it doesn't wobble under speed, which can be disasterous. The reason that 10k and 15k drives use smaller diameter platters is because of the wobble issue. As such, I really wouldn't put that much faith in the Cringely column yet because I don't see where in the article that this was addressed.

Re:Flimsier disks & MTBF? (2, Insightful)

ChrisMaple (607946) | more than 7 years ago | (#16609984)

Young's modulus:

aluminum: 69

common glass: 70 to 95

stainless steel: 190 to 200

titanium: 406

So, titanium is almost 6 times stiffer than aluminum. I'm guessing that stainless steel has fair internal damping, which might reduce wobble propagation. (I'm not a mechanical engineer.)

Disk stretch? (1)

Hoi Polloi (522990) | more than 7 years ago | (#16610082)

I think he talks about how the foil disks are very flexible and therefore can avoid head collisions and return to their previous state very quickly. I assume this flexibility and very low mass would also take care of wobbling.

I'd like to know how resistant the disks are to stretching over time due to the very high RPMS.

Re:Disk stretch? (1)

honkycat (249849) | more than 7 years ago | (#16610340)

Stretch is an interesting concern. As long as it's relatively uniform (so the disk remains nearly circular), you could probably cope with fairly large size changes by encoding tracking information either as additional data or in the modulation scheme. You've already got to deal with the varying linear velocity as you slew in and out, in addition to variability in the motor's spin rate. It'd be similar to dealing with Doppler in radio communications, albeit on a somewhat faster time scale. Since the data rate is also much higher, there'd be more bandwidth for tracking data, so I suspect that you could just run similar methods faster.

What about shock? (1)

mastropiero (258677) | more than 7 years ago | (#16609370)

Hey, I'm as much concerned about the environment as the next guy, but I would think foil platters, similar to floppies would make the disk much more vulnerable to head crashes. The disk would be cheaper and more env-friendly, but would crash fatally much more often...

Nothing new.... (1)

krell (896769) | more than 7 years ago | (#16609444)

Some guy shows up all paranoid about some problem, and wants to solve it using tinfoil. It's not like we've never seen this before.

I think he can use the same arguments to justify making automobiles out of tinfoil instead of all that nasty costs-too-much-energy-to-move heavy metal.

Re:What about shock? (1, Insightful)

Anonymous Coward | more than 7 years ago | (#16609476)

You didn't RTFA before posting did you. It discusses head crashes.

Re:What about shock? (1)

mspohr (589790) | more than 7 years ago | (#16609498)

If you had RTFA, you would have learned that these drives are much more resistant to shock since the head design creates a cushion of air that (combined with the low mass of the platter) keeps the platter away from the head.

Re:What about shock? (2, Informative)

DJCacophony (832334) | more than 7 years ago | (#16609808)

All hard drives do that. In fact, if you suddenly cut off a normal hard drives power, the momentum of the disk will keep it spinning long enough to maintain said cushion of air while the head returns to the parking position.

My first concern... (4, Insightful)

AKAImBatman (238306) | more than 7 years ago | (#16609380)

...would be the shock resistence of the material. Glass and metal platters aren't going to fold over or have the head rip through them because you hit a nasty pothole. In reading the article, however, I found this statement:

Our 10-gigabyte 0.85-inch drive can spin up, read or write data, then shut down again, all in less time than it takes to perform the same task using flash while being just as resistant to shock damage and more resistant to heat.

That's quite a bold claim! If his claims are accurate, then we may be looking at the future of hard disk drives. Micro-disk drives would become the latest hotness, and Flash would disappear entirely from our memory. IF the technology works, that is.

Time and speculative investors will tell if it's really everything it's cracked up to be. I certainly hope it is, but extraordinary claims require extraordinary evidence.

Re:My first concern... (2, Interesting)

daBass (56811) | more than 7 years ago | (#16609688)

Uhm, did you read the entire article? It seems you missed the part where he says:

The nature of our drives is such that they are very resistant -- almost immune -- to shock damage, making head crashes a non-event because the flexible metal foil yields to the head, pushed away by a layer of compressed air, rather than being struck by it.

Re:My first concern... (1)

peragrin (659227) | more than 7 years ago | (#16609734)

And depending on the head position when it is pushed away means that it could hit the next platter in line relatively easily. What we need to do is get away from spinning media. though that will take many advancements that haven't even been though of yet.

Re:My first concern... (1)

daBass (56811) | more than 7 years ago | (#16609854)

Yeah, I though about that too. But it all hinges in how much movement these heads can make in the case of a drop and how far away the next platter/head is. Obviously, the distance between different two sets of platters and disks can be greater than the distance between a head the disk it is reading/writing.

I hate spinning disks too, but they are the fastest, cheapest and most durable thing we have for big storage right now, unfortunately.

Seeing is believeing, so Mr. Cringely better be showing in that promised year from now!

Re:My first concern... (1, Informative)

AKAImBatman (238306) | more than 7 years ago | (#16609822)

I don't follow your point. I said that my first concern would be that the technology would be prone to breakage. My next point, however, was that TFA is claiming that the disks would be more reliable than current disks. I said that it is a bold claim, and that I hope it works out for them.

How you got from there to "you should have read the whole article" is beyond me. I'm not going to quote every point they make just to say that they're claiming greater reliability.

Re:My first concern... (1)

daBass (56811) | more than 7 years ago | (#16610062)

Two things: first of all, while they do not break, glass/metal platters do stop working after a head strike. In the case of rigid disks, some specialist company might be more able to recover (some of) your data for hundreds or thousands of units of your favourite currency, but the drive is still dead. So that makes the drives not folding or having heads rip through the completely irrelevant. Floppy or hard, the disk would die.

Secondly, the quote you chose - while stating that they believe it is more restantant to shock - misses the all important "how". While the quote isn't wrong, I believe the one I used is so much better at taking away fears of head crashes by explaing how they are dealt with that I couldn't help but wonder if you stopped reading after the first quote about reliability you could find.

I hope you can see both these things as constructive criticism!

Re:My first concern... (1)

AKAImBatman (238306) | more than 7 years ago | (#16610264)

first of all, while they do not break, glass/metal platters do stop working after a head strike.

This is true. However, my specific concern was in the foil bending. We've already got fairly good technology to prevent head crashes on a rigid disk. The question is one of seemingly flimsy foil bending toward a destructive end. According to TFA, they're going to use very rigid materials like Titanium or Stainless Steel to prevent it from being too flexible.

Secondly, the quote you chose - while stating that they believe it is more restantant to shock - misses the all important "how".

No, not really. It is sufficient for my comment that they made a claim directly in opposition of the commonly held beliefs about floppy platters. The "how" can be perfectly reasonable and yet still be *wrong*. It's of interest for those who wish to understand more about the technology, but it's no guarantee that the technology will work.

I hope you can see both these things as constructive criticism!

No, I do not. If you wish to add more info, be my guest. There's nothing wrong with building on each other's comments. Just don't insinuate that I'm wrong and/or missing a key piece of information when neither assertion is correct.

Re:My first concern... (1)

ultranova (717540) | more than 7 years ago | (#16610310)

Two things: first of all, while they do not break, glass/metal platters do stop working after a head strike. In the case of rigid disks, some specialist company might be more able to recover (some of) your data for hundreds or thousands of units of your favourite currency, but the drive is still dead. So that makes the drives not folding or having heads rip through the completely irrelevant. Floppy or hard, the disk would die.

Would it ? Or would it simply develop bad sectors where the head struck, with the rest of the platter still working just fine ?

Re:My first concern... (1)

daBass (56811) | more than 7 years ago | (#16610440)

Not in my experience; I have seen a fair few laptop drives die from drops and all of them died pretty good.

Re:My first concern... (1)

inca34 (954872) | more than 7 years ago | (#16609856)

Wow... this is the first comment that looks like someone actually RTFA. Good job!

And no, that wasn't sarcasm.

Reliable? (0)

Anonymous Coward | more than 7 years ago | (#16609398)

Wouldn't that make it extremely prone to head crashes, worse yet if the media flexes even just a little bit it would drastically sharpen the impact angle and possibly even rip the foil right off the spindle. Sounds like a terrible idea for anything that isn't seismically secured.

WTF? (1)

Ancient_Hacker (751168) | more than 7 years ago | (#16609406)

Aluminum goes for about 60 cents a pound, glass much less. A typical disk drive is gonna use under a nickel of raw material in the platters.

Re:WTF? (3, Interesting)

mspohr (589790) | more than 7 years ago | (#16609566)

If you had RTFA, you would have learned that the savings in the cost of the platters comes from lower manufacturing / fabrication costs, not the cost of the material. In fact, the foil platters use a more expensive material (stainless steel or titanium).

The real savings comes from the fact that the coating/finishing of the platters can be done on a big roll of foil and the platters can then be just stamped out. Standard platters must be finished individually.

He just gave a talk on this... (3, Informative)

Rhys (96510) | more than 7 years ago | (#16609438)

At the UIUC Reflections|Projects ACM conference. It was actually a fairly interesting talk (http://www.acm.uiuc.edu/conference/2006/webcast.p hp) about the same topic, maybe a little more in-depth than the article. At least more pretty pictures than the article.

Sounds like a non-starter in a desktop/server... (1, Interesting)

Anonymous Coward | more than 7 years ago | (#16609460)

The only time you'd see a difference in energy consumption would be during spin-up. Not worth optimizing such a rare case (except possibly in a laptop drive where it does happen a lot and would contribute to battery life.)

Failed physics? (2, Informative)

Rhys (96510) | more than 7 years ago | (#16609926)

The platters have (per platter) a much smaller edge, so they're going to get less friction from the air. Less friction means less heat AND less power required to keep the disk spinning at the same velocity. The area isn't that big compared to the surface of the disk, but I'd guess (assuming the heads were at the outer tracks of the disk) that the air near the spindle spins with the disks and probably causes very little if any friction, so the majority source of air friction is going to be the edge (where it moves air around the "interesting" interior shape of the enclosure).

In his talk I referenced above, he specifically stated that they were using smaller/lower power motors because they didn't need as much power as a conventional disk. Also remember that conventional disk motors may have to be "overspecced" to be able to spin the disks up to speed in a reasonable amount of time, and that may make them less efficient when they're just trying to maintain speed rather than spin up. You'd have to ask an EE on that one though, 'cuz I'm not. Just another stab that occurs to me for why it may cost a lot less power.

He also referenced making higher-RPM drives than current methods. I want to say 30k sticks in my head, but I'm not sure on that you'd have to watch the talk to verify my tylenol cold muddled memory.

Re:Failed physics? (1)

imsabbel (611519) | more than 7 years ago | (#16610064)

Who cares about the _edge_ of a thin disk, if you have the while top and bottom?
Sure, the relative speeds are highest at the end, but >90% of the friction does NOT happen on the outer edge.

Re:Failed physics? (1)

Rhys (96510) | more than 7 years ago | (#16610490)

You assume the air between platters is stationary. I assert you're wrong on your initial assumption. Air between platters should tend to rotate with the platters. Similar to making a hollow, capped tube out of the cyl's and spinning it. The air inside isn't going stay motionless, it will speed up and eventually reach a steady state with the rotation.

The read/write heads will disrupt that air flow, but I did note I was assuming they were out of the way.

This must be that New Physics (0)

Anonymous Coward | more than 7 years ago | (#16610182)

... stuff I keep hearing about. Just how much drag do you think is incurred by a rotating cylinder of almost-perfect smoothness? Reducing platter thickness will make almost no difference at any achievable rate of spin.

Oh, and try spinning a foil platter at 30K RPM sometime and see how that works out for you. I don't normally think of confetti as a deadly weapon, but like you say, we're talking some interesting physics here.

Cringely's time machine (2, Informative)

itwerx (165526) | more than 7 years ago | (#16609502)

Cringley must be old enough to remember Bernoulli disks [wikipedia.org] . (They used a plastic film but same concept applies.)

Re:Cringely's time machine (5, Informative)

itwerx (165526) | more than 7 years ago | (#16609558)

Forgot to mention, the reason film isn't used is the coefficient of expansion. There's no temperature regulation in drives (yet) and there isn't a film material in existence that doesn't expand and contract with the temperature. That's actually one of the reasons glass was introduced awhile back, data densities were getting so high that even the rigid metal platters were moving enough to become a factor.

Re:Cringely's time machine (1)

Hoi Polloi (522990) | more than 7 years ago | (#16610140)

Not to mention stretching of the material over time. Especially at very high rpms (he mentioned 30K RPMs!)

Re:Cringely's time machine (1)

Graff (532189) | more than 7 years ago | (#16610168)

Forgot to mention, the reason film isn't used is the coefficient of expansion. There's no temperature regulation in drives (yet) and there isn't a film material in existence that doesn't expand and contract with the temperature.

That's not so hard to deal with actually. Have a few marker bits at the start of each track which tell you what track you are currently on and provide you with rotational timing and have a bit of code which compensates for being off a little bit because of temperature effects. Temperatures will tend to stabilize fairly quickly and adjustments will probably be infrequent. You'll lose a little bit of speed when there is a sudden temperature shift but I'd only expect that on a cold start, something that will happen once a session on a computer usually.

They could also include a temperature sensor and just adjust their tracking based on the temperature but this kind of dead reckoning could be dangerous if your measurements are not in calibration and you are dealing with close tolerances.

Re:Cringely's time machine (1)

jmyers (208878) | more than 7 years ago | (#16609742)

He mentioned Iomega (creator of the Bernoulli Box) in the in the Article. One of the developers of this product worked for a competitor...

"Anil co-founded SyQuest, an early competitor to Iomega."

Re:Cringely's time machine (1, Funny)

itwerx (165526) | more than 7 years ago | (#16609866)

...in the Article.

Are you suggesting I RTFA?!? Egads man, are you insane? Just imagine the implications if we all RTFA! There would be no threads like this, Slashdot would shrink to a mere story-posting site, moderators would be begging in the streets, we'd all have lives - the horror...!! [sob]

:)

Scanning/Tunneling Magnetic Drive (1)

Doc Ruby (173196) | more than 7 years ago | (#16609534)

How about a stack of "foil" platters read by a single head outside the stack, that can "focus" its read-sensitive probe electromagnetically inside the stack? Maybe they wouldn't even need an airgap, just some intervening film to help "address" the different layers. Perhaps a pair of heads reading a "stereoscopic" view. Maybe that could read a whole track at once. Multiple heads around the radii could read simultaneous tracks.

This kind of tech has a lot of problems in signal/noise, permissivity/permeability, etc. But the benefit could be a drive the size of a mini-CD-single case, with dozens of microlayer platters and octets of read heads, offering terabytes for milliwatts.

Re:Scanning/Tunneling Magnetic Drive (1)

miller701 (525024) | more than 7 years ago | (#16609996)

In TFA, he says it's a 0.85 diameter disk, so it's about the size of a nickle

Re:Scanning/Tunneling Magnetic Drive (1)

Doc Ruby (173196) | more than 7 years ago | (#16610174)

That's his version. I'm not sure that scanning/tunneling magnetics are that accurate/precise in the "Z" axis. Or maybe they are, and we're looking at mm, not cm, and uW, not mW.

Re:Scanning/Tunneling Magnetic Drive (1)

freeze128 (544774) | more than 7 years ago | (#16610056)

How about a stack of "foil" platters read by a single head outside the stack, that can "focus" its read-sensitive probe electromagnetically inside the stack? Maybe they wouldn't even need an airgap, just some intervening film to help "address" the different layers.
That's an ingenious idea. Technology like that would make existing hard disks last a lot longer, because the only moving part would be the spinning of the disks. That would prevent a lot of head crashes, and also increase the operating temperature range.

I wonder if it's feasible.

Re:Scanning/Tunneling Magnetic Drive (1)

Doc Ruby (173196) | more than 7 years ago | (#16610412)

Well, only if the "stereo magnetic sensor" can work, without moving the heads.

I'm still waiting for HD makers to "invert" their tiny feature-size manufacturing from platter surfaces to read/write heads. Why not a top layer disc that is covered with sensors/probes the same scale as the data domains on the discs below them? Addressing the probe layer with/for data as a RAM page, with a "layer index" for the target disc layer on which the proble layer "focuses". Maybe a single layer at a time, with the probe scanning through the stack, read/writing as it passes. Or, if each probe layer cell can focus independently, one cell in a column per cycle. Throw "asynchronous clock" tech, and each probe cell could have its own cycle. The density and performance of such a device would put TBs on cm^3 at mW (or uW). And since the "discs" no longer rotate (saving latency, power, and mechanical wear/complexity), they can fill cubic volumes, instead of cylindrical ones, for (4-pi)r^2 extra storage volume.

I had expected all this kind of "volumetric" tech to be superceded by holographic optics. But that industry has been very slow. And photons are much bigger than we can make magnetic domains, so this stuff we're speculating about has better (imaginary, but plausible) specs.

Speed control (2, Interesting)

MightyYar (622222) | more than 7 years ago | (#16609538)

Speed control of the rotating disk is going to be harder if the disk has less mass. You basically loose a nice dampener that you had in the system.

The only real power savings would come during spin-up. Once the disk is spinning, there's no additional power used to rotate a heavy vs. a light flywheel. (Well, a little bit because of increased bearing friction, but it's probably negligible.)

Finally, if you lighten up the parts in a hard drive, most companies are just going to use the energy savings to drive the parts FASTER.

IANADDEBIAAME*

*I Am Not A Disk Drive Engineer But I Am A Mechanical Engineer

Re:Speed control (4, Informative)

Svartalf (2997) | more than 7 years ago | (#16609616)

Uhm... That's NOT quite true... Cut the power off, the disc eventually stops spinning because of friction, etc.

You need to supply a constant input of angular momentum to keep the discs spinning. Spinning a
smaller mass will ALWAYS mean a lower power input, from start to finish and everything in betweeen.

Re:Speed control (1)

MightyYar (622222) | more than 7 years ago | (#16609840)

I agree - lower, but I still don't thing "significant". Plus, as I mentioned and as they mention in the article, they will eat up a lot of the power savings by spinning up the drive faster. It's also possible, though I don't have the right kind of information, that maintaining the speed of such little mass will prove to be energy-intensive. It will be very sensitive to changes in power input, so oscillations in velocity are going to be harder to control - it's like increasing the gain in the system.

All I'm saying is that the article makes a lot of claims. All of them are possible on their own, but there is no way that there will be this "super drive" that has more platters, spins up faster than flash can be accessed, is bump-resistant, is cheaper, AND consumes significantly less energy. Rarely does it work that way in engineering :)

Re:Speed control (1)

Orange Crush (934731) | more than 7 years ago | (#16609994)

Uhm... That's NOT quite true... Cut the power off, the disc eventually stops spinning because of friction, etc.

Parent said: "Once the disk is spinning, there's no additional power used to rotate a heavy vs. a light flywheel."

Mass is irrelevant when maintaining a constant angular momentum, all else (like coefficient of friction) equal. Once spinning, aerodynamics and friction are running the show.

Re:Speed control (1)

Vellmont (569020) | more than 7 years ago | (#16610208)


Mass is irrelevant when maintaining a constant angular momentum, all else (like coefficient of friction) equal. Once spinning, aerodynamics and friction are running the show.

Except mass is related to the frictional force stopping it. Directly proportional in fact. The only question is how much drag is created by friction, and how much is created by the air resistance? I don't know, but if most of the drag is created by friction than a much lighter platter is going to have a lot less drag on it, and thus use less power.

Re:Speed control (2, Informative)

Graff (532189) | more than 7 years ago | (#16610400)

Mass is irrelevant when maintaining a constant angular momentum, all else (like coefficient of friction) equal.

Not exactly true. Remember that the coefficient of friction is just a imensionless scalar value, it is not the actual force of friction. You need to multiply the coefficient of friction by the normal force between the two objects that are moving past each other. In this case we are talking about the mass of the flywheel acting upon its pivot point. I believe the relationship of friction to the mass of the flywheel is linear so a flywheel that is twice as massive as a ligher flywheel will take twice as much energy to maintain the same angular momentum.

And yes, it is actually a bit more complicated than this depending on how the flywheel is supported on its axis but the fact remains that the mass of the flywheel does have some bearing on the energy needed to maintain its angular momentum.

Re:Speed control (1)

Khabok (940349) | more than 7 years ago | (#16610020)

Sounds fine. That means I get to have a crazy-fast hard-drive for my swap / page-file / scratch disc, and server farms get to have 10,000rpm drives that save scads of energy.

Just because most companies spin the discs faster doesn't mean that everyone will, or that it's a bad thing. The upshot is more options, with far higher peak performance on the chosen primary parametre.

Also, isn't speed controller more or less free pie when you're using steppers?

IANAE.

Re:Speed control (1)

MightyYar (622222) | more than 7 years ago | (#16610446)

Steppers have some serious performance issues, and I don't think that hard drives have used them for years. Floppy drives used them.

I have no doubt that hard drives will get lighter, faster, and maybe even cheaper. They will also use less energy in certain configurations. However, a data center is still going to buy the biggest, meanest, most dense hard drive that they can buy. The companies that make these will exploit the lighter materials to make the drive FASTER, not to use less energy. I suspect that they will also cost about the same as today's drives, but will have much better performance and capacity.

In your iPod, you will see this technology. They will have a configuration that is just an improvement on today's micro drives. Higher capacity, better speeds, etc. But you can't get everything all at once, and that was my issue with this article - it was making it sound like you can get everything all at once, when in reality this is just an incremental step.

Re:Speed control (1)

Hoi Polloi (522990) | more than 7 years ago | (#16610244)

I think you mean that the greater rotational inertia in the glass disk system tends to dampen noise in it (vibrations, etc) while a very light mass would be more susceptable to it.

"Finally, if you lighten up the parts in a hard drive, most companies are just going to use the energy savings to drive the parts FASTER."

If they drive the parts faster then you have greater performance. Energy costs vs performance, an old decision.

Old technology new again? (2, Insightful)

tlhIngan (30335) | more than 7 years ago | (#16609570)

I seem to recall in the late 80's and through the 90's a removable cartridge drive system known as Bernoulli drives. They had "floppy" media (mylar, though, not foil), The drive would spin up the disk, then insert the heads, which were like hard drive heads - floating over the surface rather than the more standard pressed against the surface (a la Zip/Floppy drives).

Ah, Wikipedia - http://en.wikipedia.org/wiki/Bernoulli_drive [wikipedia.org]

Basically, this drive is similar, just in a self-contained format rather than a removable cartridge solution?

Though, bumping the drive while spinning could do a lot of damage from precession of the platters causing the material to warp. Fast spinning disks are miniature gyroscopes.

Re:Old technology new again? (2, Informative)

Svartalf (2997) | more than 7 years ago | (#16609670)

Actually, they have a thin metal version of this technology in a removable cartridge form
that's the size and thickness of a credit card with a smartcard contact point on it for
the crypto control on the disc. 100Mbytes to over 5Gbytes in a device allegedly more durable
than Flash (it's got the same vibration, etc. characteristics supposedly, but it's write
endurance vastly exceeds Flash right at the moment...)- in a credit card's space. What Bob
did was suggest that they apply the tech to fixed disc devices- and the article talks to the
potential results thereof.

NerdTV? (0)

Anonymous Coward | more than 7 years ago | (#16609596)

A little off topic, but where the hell is season 2 of NerdTV? It was promised at the beginning of the summer and it's almost the end of the year and still nothing? Not even an update as to what's going on with it :-(

less energy consumption ? (0)

Anonymous Coward | more than 7 years ago | (#16609608)

i dont get it.

Datacenter disks spin 24/7. The energy used by the inital spin-up is null compared to the runtime.

Energy-wise it does not matter if if keep a 100gr or an 1 gr platter spinning. Its all just "wind" resistance. That gets higher the more platter you add.

So why will this 12-platter-design use less energy ?

Re:less energy consumption ? (1)

IckySplat (218140) | more than 7 years ago | (#16609746)

Because a you need a much bigger motor to drive a 100gr platter
Lighter platter = smaller motor = lower power usage
Less to do with platter friction than with the number/length
of windings in the motor itself.

Re:less energy consumption ? (3, Funny)

trongey (21550) | more than 7 years ago | (#16609802)

Think nothing is impossible? Try slamming a revolving door

Actually, modern revolving doors have a breakaway feature so traffic can go straight through in emergencies. If you try hard enough it is quite possible to slam one.
Just thought you would like to know.

Re:less energy consumption ? (1)

IckySplat (218140) | more than 7 years ago | (#16610508)

But technically, if the door is in "straight through" mode
It is no longer a revolving door... No? :)

I was always under the impression... (1)

Aphrika (756248) | more than 7 years ago | (#16609622)

...that having a heavy disk in the drive would make it more stable, easier to keep and a constant speed and generally a lot better for wear and tear on bearings and heads.

I also seem to remember that glass and ceramic platters don't expand as much as metals do during thermal change which happens a lot as drives are turned on and shuts down, so I'd wager that his idea of using tin foil, aluminium or any other metal is flawed. Seriously.

Re:I was always under the impression... (0)

Anonymous Coward | more than 7 years ago | (#16609884)

so basically what you're saying is you didn't read the article and are thus talking out of your ass?

Re:I was always under the impression... (1)

ChrisMaple (607946) | more than 7 years ago | (#16610290)

Aluminum is already in common use. Thermal problems are handled somehow. I think stainless steel and titanium are less a problem than aluminum. As long as the thermal coefficient of expansion is isotropic, it can be handled.

More platters? (1)

Jim3535 (903233) | more than 7 years ago | (#16609790)

Adding more cheaper platters to reduce cost almost makes sense. That is until you consider that the read-write heads are one of the most expensive parts of a drive. Adding more of them would substantially increase the cost of a drive.

Who Died and Made Cringely Hari Seldon? (5, Interesting)

Cr0w T. Trollbot (848674) | more than 7 years ago | (#16609798)

Since Cringely isn't nearly as big an idiot as Rob Enderle or John C. Devorak, at least this doesn't seem like rank psuedoscience. But there seem to be an awful lot of unchallenged assumptions about the technology that need to be worked out for it to be commercially viable.

In particular, I'd like to see evidence for the following claims:

"They could design new families of disk drives that held up to three times as much data in the same space, were more reliable, actually cheaper to build, and used 70-95 percent less energy to run than the current state of the art."
I'd sure like to see the assumptions and numbers underlying that equation.

"The technology in question replaces the aluminum or glass platter in your hard disk drive with a "platter" made from stainless steel or titanium foil that is 22 microns or 25 microns thick, respectively. The materials cost more but we use so much less of it (the disk is so incredibly thin) that the total material cost is substantially less. This "floppy" material has the same kind of magnetic coatings used on standard disk drives and our drives live on the same technology growth curve as those others. The way we obtain greater storage density is simply by putting more platters in a drive (say 12-15 instead of 4-5 in an enterprise 3.5-inch drive) because they are much thinner and can be stacked closer together. The only parts of the drive that are significantly different are the platters and the heads and the heads vary only in having an extra slot. There is no rocket science here, but what science there is is patented."
Gee, Cringe, which do you think costs more: The raw platters themselves, or the read/write heads? I would say the latter. So you're going to drop the costs of hard drives by doubling the most expensive component? Huh?

The advantage of our drives goes beyond enterprise applications. We are able to build cheaper drives, for example, because our platters cost less to make and the nature of our flying heads is such that dust is sucked away from the head-disk interface, meaning the drives do not have to be assembled in a clean room.
Sorry, I'm not buying this at all. You don't think a non-cleanroom enclosure is going to result in data loss on the platters themselves? Even if you're not getting particles during the read/write phase itself, you're getting them on the platter. I'm not buying the logic here.

Who needs flash in general as a mass storage technology? Our 10-gigabyte 0.85-inch drive can spin up, read or write data, then shut down again, all in less time than it takes to perform the same task using flash.
Sorry, I'm not buying this at all. Until the advent of true Drexlarian nanotechnology, I doubt you're going to see a mechanical action (you still have to move the eread/write heads) beat an eletronic one (reading from Flash).

I'm not saying that the technology Cringely talks about is impossible, I'm saying: A.) There seem to be a lot of unwarrented assumptions underlying his logic, and B.) Implementation always has unforeseen hurldes and obstacles that will make these drives seem like far less of a slam-dunk vs. current technology (or more specifically, where regular drive technology will be 18 months from now) than it appears.

Finally, once it is ready, I'd like to see real-world tests for speed/electrical consumption metrics with existing technology. There might indeed be some savings, but I seriously doubt they are as dramatic as Cringely claims.

Crow T. Trollbot

Re:Who Died and Made Cringely Hari Seldon? (1)

NewWorldDan (899800) | more than 7 years ago | (#16610150)

Meh, I seem to read about an amazing new breakthrough on these pages every other week. I'll believe it when I see it, which seems to be about 10% of the time.

Put your money where your mouth is (1)

Stormcrow309 (590240) | more than 7 years ago | (#16609966)

I see this solution to be prone to data errors. Therefore, I suggest that the vendor puts their money where their mouth is. Put them in some dozen tablets at a college for students and test the fail rate. Stick them in a SAN for a large data center and test the mean-time to failure. Hell, run Slashdot on them. I want to see failure, power consumption, and shock test data.

if they want to sell this... (0)

Anonymous Coward | more than 7 years ago | (#16609968)

...they have to wiggle the term "nano" in there. It doesn't matter if it is nano or not, "nano" is the tech buzzword now, everything new and shiny has to be nano to excite the vulture capitalists.

related: heads (1)

mugnyte (203225) | more than 7 years ago | (#16610074)


  I've always been curious - why don't modern drive have a spiral array of heads per suface, instead of the slower mechanical heads? It seems like track-seek speeds would disappear in such a design. Is the cost of a drive head than great, and how much of that cost is due to the movement mechanism itself?

Idiot Proof (1)

TranscendentalAnarch (1005937) | more than 7 years ago | (#16610166)

I have enough problems with current hard drives (albeit cheap and old ones) dying when some dimwit in my office kicks the computer underneath the desk as he's trying to lean back. I can only imagine how fragile these drives will be compared to current technology.

eh? (1)

popisdead (594564) | more than 7 years ago | (#16610460)

Calling this selfless self promotion is like validating that MS 'had' to spend 1 million in the first week of Win 95 on advertising.
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