[ESHOP launched] Trezor: Bitcoin hardware wallet

[molecular]

ok, gonna follow this for real ... I'm a sucker for hardware prototype pics.

yeah, hardware prototype porn... not even cable porn comes close

[slush]

First preview of the design. Dimensions are 60x40x10 mm.

[molecular]

First preview of the design.

cooool!

[slush]

First prototype of Raspberry Pi shield:

[slush]

Modified eyelet.

[chrisrico]

Oh wow, I had no idea it was going to be small enough to fit on a key chain... that's pretty fantastic.

I think I like the modified eyelet design better.

[2112]

Modified eyelet.

Both are very nice, but in the original design the eyelet was much stronger.

http://en.wikipedia.org/wiki/Stress_concentration

Perhaps you should consider moving the old eyelet to the new position, but maintaining the original shape that had smooth radius-of-curvature changes. It will be cheaper than the metal inlay reinforcement that companies like RSA (or car manufacturers) use in their keyfobs.

[slush]

Both are very nice, but in the original design the eyelet was much stronger.

RSA token you mentioned is from plastic where the stress on the material may be an issue. As far as our casing is from metal, I don't think we need to care about it. However we will have some casing prototypes soon, so we will see...

[Mushroomized]

Amazing work!

[2112]

RSA token you mentioned is from plastic where the stress on the material may be an issue. As far as our casing is from metal, I don't think we need to care about it.

Actually the RSA's design isn't tough. It is very resilient because of the eyelet attachment turns freely and completely avoids the shear stress.

If you are going to die-cast the metal ask the mold designer to optimize the eyelet for the manufacturability instead of just plainly making a bid for the existing design. As it is right now you'll have cracks in the left, narrowest portion of the eyelet and the possibility of voids in the bottom, widest portion. I'm pretty sure that your current design could be spin-molded properly (rotocasting). But for the standard die-casting the metal will have to flow to the widest, bottom, portion of the eyelet through the two much narrower branches. The eyelet will be under internal stress just from the uneven thermal shrinking of the metal after the casting is done.

The original design was obviously optimized for the best manufacturability: the narrowest portion is even and farthest away on the path of the metal flow. Although it does look weird to someone unfamiliar with the area rule.

Form follows function? Mind over matter?  

[molecular]

Both are very nice, but in the original design the eyelet was much stronger.

RSA token you mentioned is from plastic where the stress on the material may be an issue. As far as our casing is from metal, I don't think we need to care about it. However we will have some casing prototypes soon, so we will see...

!!! metal? how cool is that!

[slush]

!!! metal? how cool is that!

We rejected plastic because we believe that our valuable bitcoins need something more robust :-). So far colored eloxed aluminium and steel are in game. Aluminium looks better as steel has cold feeling (well, it's cold storage, but... :-) ).

Plus for the future, we also have an idea of super-robustness casing for limited edition ;-). But now back to work...

@2112: I edited the post above at the same time you sent the reply, so I repost it once again. Thanks for your feedback, I think this is valuable information and I'm not so experienced in building hardware stuff. We'll have physical prototype in next days, so I'll focus on the eyelet robustness. Nothing is set in stone yet, so if I'll see any possible issue with it, we'll redesign the casing.

[2112]

@2112: I edited the post above at the same time you sent the reply, so I repost it once again. Thanks for your feedback, I think this is valuable information and I'm not so experienced in building hardware stuff. We'll have physical prototype in next days, so I'll focus on the eyelet robustness. Nothing is set in stone yet, so if I'll see any possible issue with it, we'll redesign the casing.

I sincerely wish you good luck with this. Now that I had a moment to think, I realize that most of the short-run die-casting manufacturers are working in the toy industry. They may not have the required strength information available at all. The toy industry is strictly form over function: the products are almost exclusively for display only. They will talk about surface smoothness or detail fidelity, not about internal voids or ultrasonic inspection or measuring the residual stress by X-ray diffraction.

I'm not mech-eng myself, but we used the mech-eng labs as a subsitute during the construction in the el-eng building. One can learn a lot by just passively staring at the cool experiments they make.

[allten]

Slush,
    It's looking nice and coming along well.
your enthusiasm you bring is surely going to make this a reality.

I have the schematics for the OLED design, libraries, and BOM.
Since my purpose was to help push hardware wallet technology forward, I would hate to see it go in vain.

If you think it would help, let me know and I will post what I have available.

[slush]

I have the schematics for the OLED design, libraries, and BOM.
Since my purpose was to help push hardware wallet technology forward, I would hate to see it go in vain.

I'm starting to realize that this project is not about programming only, but also about logistic and management, so any help in programming part is highly welcome. We'll release everything under opensource license, so I believe this won't be about "stealing" from anyone's works....

[luicon]

hi

what could happen if someone steal your device? physical access to it means lost the money?
or there is a way to enter some kind of pin with the two buttons of the device?

[kalleguld]

hi

what could happen if someone steal your device? physical access to it means lost the money?
or there is a way to enter some kind of pin with the two buttons of the device?

The wallet in the device could be encrypted, and the password sent from the computer every time you send a transaction. That way, you'd need the device and the password to transfer money.

Haven't followed this thread, so I don't know if it's considered, but it's absolutely possible.

[luicon]

so i guess if you lost the password you are done right?

[ercolinux]

so i guess if you lost the password you are done right?

Actually you've to choose from high security of the system or simply of recovery of the data.
IMHO this is the best approach to security: one thing you have + one you know.
Only better way is to replace the password with the hash of a biometric scan (fingerprints maybe) but in this way cost are higher and not all devices can support it.

[slush]

what could happen if someone steal your device? physical access to it means lost the money?
or there is a way to enter some kind of pin with the two buttons of the device?

Device can be protected by password.

The seed (few words required to recover your coins on another device or on desktop wallet) is printed on the display during initial configuration (after you buy it). You should store this seed somewhere at safe place, so even if you lost the device or forgot the password, you can recover your coins.