Brainstorming for an Opensource Hardware portable backup device.

Spinning this off from discussions in another thread for a task I might try to tackle with some friends over the winter. (I'm Canadian and don't play hockey or own a snow mobile. I need lots of hobbies for a few months of the year.)

The goal of the project is to come up with a design using mostly off the shelf parts that can be ordered from any major supplier website, built, assembled, and programmed by anyone with a decent skill with small electronics. The idea for the product would be a simple, flexible, and reliable option for backing up photos without the use of a larger computer.

The purpose of this thread is to basically bounce ideas back and forth on how the user interface should work, what features such a device should need a minimum, and things that could be added on later.

In my mind the design should be simple, and consist of modular primary function components to offer flexibility in easily assembling a tool that will do the job you the user needs.

Things like having the memory input systems being apart from the main control system, memory storage being a general interface so you can use your choice of storage, (Direct mirrored removeable cards vs an array of small fixed CF/SD cards vs full sized hard drives), data input methods as their own modules, so you can easily build it with SD/CF, one or the other, multiple cards, etc.

The way I would want to configure mine would be a long narrow box, a little wider than a CF card. Include CF, SD, and a USB or ethernet connection (so the device can be connection to a computer later) at one end with a spring held waterproof silicone seal. Internal battery pack over the main board, and a custom built RAID controller over a bank of high capacity SD cards, fitted at an angle to reduce space. For controls, use water proof buttons and a simple multi-line LCD output to display things like file names, and general data to let me know how things are with the device and transfers.

Minimal, compact, and easily holding 256GB in less space than a full size drive would be for similar or less cash. (Not overly worried about overall speeds personally.)


So, if you were to have your own custom field backup device, what would be important to you? What features would you need, what things would be 'nice to have'?

With any luck this idea will catch on, and other people will jump on working on the project as open source. Possibly even getting this off the ground before I would get around to it.

You may want to consider which opensource license you want to use to cove the device. And technically you are designing opensource hardware (OSHW), which is fine under one of the existing opensource licenses. http://opensource.org/

I'd think the device could be standalone in that it would use a programmable chip like the Parallax Basic Stamp, or similar. Maybe use a form of imbedded Linux to run the operations. Storage options could be networked so they're reachable from any computer anywhere in the world. That was my job for many years, so I'm biased.

Interesting. For me, I'd prefer to have the ability to connect two external USB hard drives so I can move photos off my cards and duplicate them at the same time. I typically use a netbook and some software to perform this function for me. I point the software at the drives, set some rules for the files (naming, numbering, etc) then press a button and walk away.

For licensing I would prefer a fairly relaxed and open license, one that basically says "Here is some data, now go run off and play with it. Be nice and reuse this license if you want, or not." (I'm really not a fan of the hypocritical 'freedom' of GNU.) But that isn't something I really care too much about at this point, and will cross that bridge some time later if I ever get something that a license would matter for.

For now I'm happy with general concepts, ideas, and goals.

And Daphatty, thanks for that input. I hadn't really considered drives fully external to the device, but rather was thinking more of a single device containing the whole package. But I can really see where that could be valuable for work flow.

For naming rules and such, would it be important to be able to edit those in the field, needing a full keyboard layout, or would using your workstation back home to make predefined logs be good? How much control in the field is a major sticking point for me. Personally I would want something that will provide me clear feedback on data amounts, file sizes, counts, etc, where other users have commented that they merely want a button and a few LED indicators.

Basically take a long look at the HyperDrive ColorSpace UDMA and improve upon it in any/every way you can. Its pretty much the best option out there for this type of device to date. It even has a scripting language to lay out your own custom processes. Excellent battery life, small portable size and the ability to use any SATA laptop HDD or SSD all for $249 makes it a hard product to beat.

Luckless wrote in post #15035418
other users have commented that they merely want a button and a few LED indicators.

Although I'd have to agree that the Colorspace is the best of these devices, I think the Nexto ND2700 is a lot closer to the sort of device you're talking about here. No fancy screen, just a mono LCD. Only one control button.

throw in a nice, powerful wifi uploader, that will spool off the hard drive after the card has been removed....

oh yea...

God no, dont waste time with Wifi. Itll only add expense, GUI complexity, battery life sucking, etc. And upload to what? A nice slow public hotspot? Yuck. Waste of time and design.

OP, it would be great to see another such device. Consider removable batteries and backing up to a USN hard drive.

thedge wrote in post #15044559
Consider removable batteries

Removable batteries are a PITA that do nothing but add bulk (because you always need to carry a spare set around). Again, Colorspace and ND2700 has it right - a non-replaceable internal battery that gives 12 hours usage and uses a USB-mini port for recharging. USB charging from mains or car or solar is, nowadays, near-ubiquitous.

thedge wrote in post #15044559
God no, dont waste time with Wifi. Itll only add expense, GUI complexity, battery life sucking, etc. And upload to what? A nice slow public hotspot? Yuck. Waste of time and design.

OP, it would be great to see another such device. Consider removable batteries and backing up to a USN hard drive.

Oh def agree with you here! They put Wifi Support in the new UDMA 2 via an external adapter. Why on earth would I need/want that in a device that Im just using to dump my memory cards into so i can keep shooting?!

hollis_f wrote in post #15044615
Removable batteries are a PITA that do nothing but add bulk (because you always need to carry a spare set around). Again, Colorspace and ND2700 has it right - a non-replaceable internal battery that gives 12 hours usage and uses a USB-mini port for recharging. USB charging from mains or car or solar is, nowadays, near-ubiquitous.

Uh, user replaceable is a pretty important thing. You do know the ColorSpace has a user replaceable LiIon battery and they sell spares and an external charger for them as well? Pretty cheap too for the spares.

Personally I was planning to use a battery of AA cells, but very much open to suggestions on other battery options.

Why do I like AA? Because they are everywhere. That, and I already have a growing collection of eneloops anyway.

However, as an open source project, this means that you would be able to pick your own details like the actual battery pack. Anything that conforms to the device's required input on voltage and minimum amps and a suitable capacity can be wired in as you please. If I develop a design that works, and I am happy with the build quality I can do, I may be willing to produce a few extra to sell to non-technical types, but it will be up to someone else to produce something that is actually up for sale.


Designing it as a device that will appear on a general network, like a printer or NAS box, etc, is easy enough, and that means a wifi option is also easy to add or leave out. I do know there are several options on a basic network card with options for wifi or standard ethernet, and the cost difference between the two didn't seem that high. So designing the option of wifi at a high level is easy enough, and then most of us can just happily ignore it and never touch the thing again.

And honestly I can see how wifi could be useful for such a device. Get back home from a shoot after a long drive, during which you have had all your cards backed up to the single drive, then you just pull the thing out, hit the power switch, press the wifi-sync button, and leave it on your kitchen table while you go deal with other things. Come back after a shower and some food, and your files have all been synced with your main home system without you having to enter your office or find where the cat has dragged your cable to.


Other thing to consider. For those with existing solutions to this problem, are there any aspects about current designs that annoy you, or that you feel are lacking?

Here is what the ColorSpace is using for power: LINK and LINK

That looks a lot like a Li-Ion AA cell.

ben_r_ wrote in post #15045240
Uh, user replaceable is a pretty important thing. You do know the ColorSpace has a user replaceable LiIon battery and they sell spares and an external charger for them as well? Pretty cheap too for the spares.

OK, the Colorspace uses a battery that can be replaced, not a battery that must be replaced for recharging. To recharge the Colorspace I need a USB cable and a mains-USB or car-USB charging device, which I'll have anyway for phone charging. With AA batteries I'll need a spare set of batteries plus a charging unit.

Luckless wrote in post #15045417
That looks a lot like a Li-Ion AA cell.

Its about twice the size of an AA. Apparently it is a very common model 18650 LiIon battery. A size comparison with a standard AA can be seen here: LINK

hollis_f wrote in post #15045420
OK, the Colorspace uses a battery that can be replaced, not a battery that must be replaced for recharging. To recharge the Colorspace I need a USB cable and a mains-USB or car-USB charging device, which I'll have anyway for phone charging. With AA batteries I'll need a spare set of batteries plus a charging unit.

True true.