Freefall Sensor Technology on Hitachi 2.5'' Hard Drives?

I know Western Digital has Free Fall Sensors as well as Seagate for their 2.5''. Does Hitachi have such technology on say their 7K320 or any of their 2.5'' internal hard drives? Does it go under a different name?

 

Their is no point in having a freefall sensor. By the time the sensor engages, the damage is already done.
You must realize, that a harddrive is a mechanical drive. It has spinning platters and heads which move across the drive. The heads do not physically touch the disk under normal use. Their is a very small gap between the head and the platter(disk). When a harddrive is dropped, the head will scrape against the disk (if the fall generated more G's than the drive can take, while operating). Having a free fall sensor really does nothing, cause it takes less than a second for your laptop to fall and cause damage to the drive.
A free fall sensor, works off of electrical conductivity between the head and the platter. When they instantaneously touch, the actuator arm, which moves the heads are told to move off of the disk. Unfortunately that process of moving off of the disc takes much longer than it takes for the damage to be done.

In all regards, the free-fall sensor is just marketing, as was the flash memory based hybrid disk drives, which have no advantage at all.

I hope this helps,
Hitachi doesnt use these sensors cause they are not worth having. They having harddrive encryption technology on most drives, which is much more handy to have.

K-TRON

 

ktron,
That is very interesting, I always wondered about the drives that had them. How does this compare to the concept that is behind the thinkpad hardrive protection? I think the thinkpad has the technology built into the BIOS and not the drive, but is it any different/better?

 

How ironic for you to say "It's just marketing"

http://www.pc.ibm.com/us/think/thinkvantagetech/aps.html
The head parks itself with in 500ms. Just some simple thinking: 9.8m/s/s is acc. to gravity. Even if if your notebook only falls a distance of 1cm, the head will still park in time- but then it's only 1 cm fall. Bottom line: the engineers behind active protection or similar systems designed the system so it would stop the disc BEFORE impact in any fall distance. And I would rather have a stationary head crash into platter than a moving one.

and I think the correct term here is: accelerometer.

 

This is a very true statement ^^^
When I meant it was for marketing, I know it works for some instances, but it is not flawless, damage can still be done depending on the situation. Most people who read that, see that wow that means my data can never be lost, which is untrue. It is almost like a false sense of security.

The disc may not be damaged as much by having the sensor, but to my knowledge the discs are still rotating, only the head pivots away from the disc. So if the notebook falls, and the heads move out, what happens when the head is only half way to its parked position, when impact occurs. The disc will still be rotating, and now you have destroyed the entire outer part of teh disc. It is sure hard to describe, but the head will be moving to its parked position (which is outside of the disk area), As the head is trying to move off the platter, the discs are still spinning, and say the head comes in conact with the disc for 200ms. at 5400 or 7200rpm, you are still destroying a lot of data. Whether it is worth it or not, is up to you, but I have never seen a drive with free fall sensing withstand a fall. (without any data loss)

K-TRON

 

what about when you are moving ur laptop around while operating the drive? then there is some protection offered right?

I have a T61p with a hitachi 200gb 7200rpm drive with FDE... and I notice a small icon that indicates HD stopped when i move it slightly fast or place it on a surface a little hard. and it's nice to know i can't cause damage by moving it around... I wanna clarify if you think this offers no real advantage?

Thanks!

 

This is a very interesting discussion, is there anywhere were they have actually tested the effectiveness of the free fall sensor?

 

The Free Fall Sensor technology used by the Seagate Momentus 2.5'' hard drive explains that what happens is this.

Once the notebook falls a distance of 8 inches, the Free Fall Sensor causes the head of the hard drive to lock into place and stop spinning so despite the fall, the head of it doesnt scrape the disk. The time it takes for it to engage is 1/3rd of a second.

Sounds pretty effective to me.

 

hey, btw looks like my hitachi drive might not have a free fall sensor. My thinkpad has something called an active protection system, which is probably an accelorometer on the motherboard... IF any movement/shock is detected, it "stops" the hard drive... i'm quoting them now -

"When the Active Protection system is enabled, it protects your hard drive when the shock sensor inside your ThinkPad computer detects a situation that could potentially damage the hard drive. The protection system stops your hard drive by moving the read/write heads of the hard drive to areas that do not contain data, and may also stop spinning the disks of the hard drive. The hard drive is less vulnerable to damage when it is not in operation. The protection system turns the hard drive on again once the shock sensor detects a stable environment (minimal change in system tilt, vibration, or shock). When the protection system detects system motion and stops your hard drive, the following message is displayed."

 

Yes judging by that it sounds effective. But it may be just a marketing story giving a false sense of security. At least that's what I K-Tron seems to say.

I would like to see someone who has actually tested this.

 

I'd say carth's post below mine is a marketing story as it doesnt actually state the conditions in which the thing actually activates.

Samsung provides actual specifics on what it does, when it does it, why it does it. Free Fall Sensors have to be there if they mention it. Take Western Digital, their Scorpios got Free Fall Sensor drives and non. Free Fall ones are more expensive than non-Free Fall. Its definitely not simply a marketing ploy.

What we have to consider is whether the technology is actually beneficial or not judging by what it does.

 

More expensive and 'not a marketing ploy' doesnt sound right (Not that im saying the FFS is a gimmick). Sounds like good stuff to me, any real tests done to this? I can imagine it would be hard since they will need to open up the hd to check the platters

 

FFS is an additional feature, its like HDTV is more expensive than SDTV. Is HD a marketing ploy since it costs more and offers "high definition" when you can watch TV normally? Yes, but it works.

Like I mentioned, the specifications of Seagate Momentus FFS is drops 8 inches, locks head in a third of a second.

Though I highly doubt anyone would be willing to drop their hard drives on the floor just to test it out. lol.

 

Noone doubts that the head will lock. The question is: is the locking of the head enough to protect your data when your laptop actually falls. Or is it a false sense of security and is your data destroyed anyway.

For some people it is a real benefit, for some people it's just marketing.

For example: Some people buy a 1080p tv while they're sitting at a distance where they can not see the difference between 1080p and 720p. Still they are proud of their Full HD TV.

 

Or if your hard drive data is still protected despite dropping a hard drive without a FFS. So even if it hits the floor, it won't matter.

I noticed the Hitachi 7k320 does have impact resistance, maybe the impact resistance does enough to protect the hard drive. Who knows.

 

If you drop your laptop then you deserve what ever happens to your data.

The way Forte explains it it sounds effective.

 

Wasn't the main question here if the Hitachi's have a free fall sensor ? Besides non of the HD manufacturers market their free fall technology as being 100% effective in falls. Their mechanisms simply engage to minimize potential damages from falls. So needless to say it can prove useful in short range falls and it can hardly be seen as a gimmick. Besides, catastrophic falls or falls from great distance would more than likely damage more than just the harddrive.
Bottom line, always have a redundancy plan whether it be one of the iterations of Raid or just simple spare backup drive and regardless of any spills, thrills and falls you would be able to recover from any data loss.

 

The question is whether your assumption is correct. Not to say that it isn't.

Some people believe the claims of storage companies. Others, including me, are more sceptical.

But then again, if it did not work, they may get claims of people who lost their data I guess. At least that's the idea we have here in the Netherlands about Americans; they sue everyone for everything they can sue for.

Still I find it hard to believe that no one has actually tested this. I mean they do crash tests with expensive cars, why wouldn't they with harddrives.

 

Well I think of it this way: If the head is going to crash into platter, It's better to have JUST the platter moving than to have both head and platter moving on impact.

 

I was thinking about this on the train to work today. It would be more effective to stop the disk than the heads. If the harddrive standard height was 12-15mm, this would be very plausible. All the manufacturers would need is a solenoid, which would press a brake pad against either the shaft of the motor or a flywheel, solenoids are very strong and can easily stop even a 7200rpm motor in less time than the heads can be parked. The solenoid would have to click and move about 0.5mm, while for the heads to be parked, the actuator arm may have to move 30mm or so.
Including a free fall sensor should not increase the price of the drive by much, you can buy free fall sensors from Mouser electronics or other huge electronic warehouses for less than a quarter.

K-TRON

 

that thing i quoted was just the first paragarph of that page... and i think the reason it doesn't describe the conditions in which it works is cos it allows the user to change it's sensitivity and stuff like that.

i don't think it's really a marketing gimmick... i mean, ibm came up with the idea first if i'm not mistaken and it was only supposed to act like an 'air bag'... just to add a layer of protection... it's foolish to keep saying these are just marketing tactics without having any basis of argument, just because we aren't sure how it works! of course it might not work all the time! but i'm sure it works a lot of the time... and like someone said if you drop ur laptop while using it, you deserve to lose all ur data! lol... and like ktron pointed out, its very possible to stop the platter even at 7200 rpm in a split second - especially cos the platter is so small. this is probably done when a fall is detected, slight movement might only need the head to be parked before the comp is stable again... the companies we are talking about have spent a lot of stuff engineering them and it's just sad to brush it off saying without any evidence that it's 'just marketing'!

 

Well you know each has his own opinion. I personally am a lot more sceptical of claims made by manufacturers than you are. I am not saying it's all marketing, I just want to see it proven.

If you look at the promised transfer rates and latency on the same specsheet, you know where I am coming from. That's why I would not buy a drive based on spesheets, I want real benchmarks.

 

yea to be honest I don't take manufacturers claims very seriously either, i mean they tend to find loopholes and try and just exaggerate a certain value or feature and really distort the capabilities of the product for real...

but about the free fall sensors or active protection system, I think it's a case where they offer a layer of protection, but only till a certain point... of course i'm not going to shake the laptop hard enough or drop it till it fails, but it certainly offers more protection if i want to move my laptop from one place to another, it's possible with any laptop, but it's just more secure when the laptop can detect a sudden movement and take preventive action... and it's potentially protecting priceless property!

 

I agree with that. And it would very interesting to know what that certain point is.

 

haha... well yea that would be nice. I have a feeling there might be some evidence hidden somewhere on the net. it's been around for quite sometime so there has to be a comparision or something.

 

Yeah that's what I thought too. I searched briefly but did not find anything.

 

I am not familiar with Hitachi's implementation of the FFS, but if it is anything like the Thinkpad APS system it is far from just a marketing ploy. I recommend to the people who've expressed that opinion to read a little about how a HDD works instead of saying nonsense.
When a HDD falls while the head is not parked (i.e. during use), the head, which hovers only nanometers above the disk, can 'crash' into the desk, gouging it beyond repair or recovery. When a HDD falls while the head is parked, yet the disks are still technically moving (such as with APS, and as I understand, the FFS) the disks don't actually hit anything. Yes, if drop a HDD from very, very far the disks may get impacted nonetheless, but it should be safe with it falling off your table. And if it's not, you can be sure it's in much better shape than it would be without the sensor.

EDIT: Although probably no one would sacrifice their laptop to prove that the FFS works, here's a video showing the APS in action: http://www.youtube.com/watch?v=cYjAgMcU-ow

 

Guys, how do you know if the HDD comes with free-fall sensor? I ordered a Dell Vostro 1310 2 weeks ago and the HDD was a Hitachi 7200rpm 160GB free-fall (HTS722016K9A300). I don't want to try shaking the entire laptop but how would I know if the free-fall sensor kicks in?

Besides, I have downloaded Hitachi 7k200's datasheet; never even mention anything about free-fall sensor.

 

Since I haven't found any actual field testing of the FFS/GFP technology (WD calls it "Free-Fall Sensor", Seagate calls it "G-Force Protection"), I tried to check out their data sheets. This is what I've come up with so far — please feel free to check out the respective HDD data sheets and correct me where needed (plus always keep in mind what PhilFlow has said regarding the Company-specs-vs-Reality-checks).

WD's Free-fall sensor: As an added layer of protection, if the drive (or the system it’s in) is dropped while in use, WD’s free-fall sensor detects that the drive is falling and, in less than 200 milliseconds, parks the head to help prevent damage and data loss. (Taken from here and here.)

Seagate's G-Force Protection: When a laptop is dropped, the most catastrophic damage to the hard drive occurs when the head scrapes across the surface of the disk, causing potential data loss. G-Force Protection protects the hard drive against shock by sensing when the system is in a free-fall state, moving the heads off the platter and locking them in place. All this happens within three-tenths of a second when a change in acceleration equal to the force of gravity is sensed. G-Force Protection results in added durability and reliability during accidental drops. (Taken from here and here.) A free-fall sensor technology, to help prevent drive damage and data loss upon impact if a laptop PC is dropped. The sensor works by detecting any changes in acceleration equal to the force of gravity, then parking the head off the disc to prevent contact with the platter in a free fall of as little as eight inches. (Taken from here.)

So, the FFS/GFP feature is a head-parking mechanism that applies only when the HDD is in use, and (WD claims that it) works faster in Scorpios Black than in 7200.2/7200.3's. It doesn't expand the hard disk's nonoperating shock resistance — and I don't see how it might expand the operating shock resistance, either, since both FFS/GFP-enabled and normal HDDs in the same series share the exact same impact specs.

The impact resistance specifications for the 7200rpm 2.5" HDDs are the following:
Hitachi 7K320 — 400G operating shock / 1000G nonoperating shock (spec)
Seagate 7200.3 — 350G operating shock / 1000G nonoperating shock (spec)
Seagate 7200.2 — 300G operating shock / 900G nonoperating shock (spec)
WD Scorpio Black — 275G operating shock / 900G nonoperating shock (spec)

 

That's interesting because according to the specsheet and Zazula's post in the other thread 7K200 does not have FFS.

If that is true you would be able to claim from Dell what you paid for. But then again you may get a slower drive in return, as the 7k200 is pretty fast.

 

I think there is a misunderstanding here, so I will try and describe the system.

1. A normal harddrive has heads that hover on the sides of the disks, it is a tiny gap something like 1/40th the width of a human hair. Because of this, when a harddrive drops (and is operating) inertia can cause those flimsily little heads are going to impact the disks. Example of this floating idea:
http://www.logicsmith.com/hddes4-2.gif

2. There are different versions of FFS. The thinkpad system is based on an accelerometer independent of the harddrive. When it detects acceleration that could damage the drive (how anal the program is can be set on the user). When it decides there is danger, it parks the heads. Other drives are built in so that any computer can have this protection, using different types of sensors, an accelerometer can be much faster then one relying on sensing the electromagnetic changes as the heads collide. (1CM vs 8 inch).
Example of old drives, or current drives running:
http://www.networkingaudiovideo.com/pictures/harddrive-thumb.jpg

3. The most important thing to understand here is that parking the heads means removing them from the drive platters.
Notice where the heads are now:
http://64.202.120.86/upload/image/a...-hard-drive-exposed/samsung-hhd-on-laptop.jpg

I would tell you that these systems do in general work being harddrives can survive short falls without them. The shorter the delay the better it is. After they are parked the drives have much better ratings since they are effectively turned off, and only damage to the unit (rather than the platters) is an issue. Some are better than others, but most of them do work rather well.

 

According to Dell's site it comes with free-fall sensor:
Hitachi Travelstar 7K200 (SATA) Hard Disk Drive User's Guide

But it is not shown on Hitachi's datasheet:
Travelstar 7k200

I guess I should ask Dell about this

 

Maybe Dell got a special version that's not being offered for retail.

Yeah ask Dell.

 

Are there any reviews for those 2.5" HDs with free fall sensor?

 

I accidentally did a couple test. WD Scorpio blue 160GB. I dropped my netbook at least 10 times from table height accidentally. I haven't had a bad sector on the hdd yet.

 

I dropped a 3.5" 1TB HD without fall sensor a couple of times by accident but after the last time it's sort of dead. It sounds okay but you can't read or write data anymore.

 

Hopefully the Free fall sensor will be able to do what it was intended to do and be more of a preventive solution to HD issues.. Nice thread, I hope they apply this sensor to all of their future HDs and improve the technology from time to time..