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Building my Own Laptop

bunniestudios.com

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Re: Building my Own Laptop

#31

Post by beambot »

3amOpsGuy wrote: post #25

I'd be conscious about the LIPO battery choice & potential fire risk. They're absolutely fine when treated with care (i've had many for years for RC planes & helis and never had more than minor issues), but i'd be concerned people are used to not having to care about their batteries. If you discharge them below ~ 1.1v per cell (higher for cheaper ones) they don't quite explode but it's not a slow burn either: http://…

Nah, just use lithium iron phosphate (LiFePO4) batteries. They're not quite as energy dense as LiPO, but they have longer lifetimes, better power density, and are WAY safer.

You'll see a lot of roboticists using these already (for safety reasons). For example, you can grab some nice Turnigy LiFePO4's at most hobby shops.

Re: Building my Own Laptop

#32

Post by andrewflnr »

dfox wrote: post #30
semisight wrote: post #4

Earlier quoted context omitted.

If not more ambitious, considering the small, unfriendly nature of laptop hardware. Good luck to OP!

I would assume that building your own lightsaber, given it's form factor, would involve significant amount of laptop-like small, unfriendly electronics (not to mention fiddling with force fields and other advanced physics) :)

You would think, but based on the literature they don't actually seem to be that finicky. Just stick some kind of crystal in some kind of case, with a couple other off-the-shelf components, and that's it.

Re: Building my Own Laptop

#33

Post by pasbesoin »

Don't know whether this fits, but here's something I'd like from the power system: Automated battery maintenance. I'm plugged in, a lot, and I forget to / blow off periodically cycling my battery. (Admittedly, maybe I'm unusual / an edge case, in this, and my thoughts here are of little general value.)

I'd like a power system that can be made to periodically and contextually select to run from battery, even while plugged in, so that the battery can be cycled in a manner that maintains its capacity.

So, when, every some weeks, I do need to run from battery, it's still in decent shape. Without my having to manually ensure this on an ongoing basis.

I doubt its' a priority for Bunnie, but what the heck, I'll throw the idea out there. When else do I have even a chance of having any input into a laptop's design?

Oh, and thank goodness for an(other) open alternative to "secure boot" (maybe nice in principle, but very potentially malicious in current execution).

Re: Building my Own Laptop

#34

Post by caycep »

beambot wrote: post #7

Incidentally, the guy creating this is Bunnie Huang -- the guy who designed the Chumby, was famous for Xbox hardware hacking, and did an awesome (open-hardware) MITM attack on HDCP at CCC [1,2]. [1] http://events.ccc.de/congress/2011/Fahrplan/events/4686.en.h... [2] video: http://www.youtube.com/watch?v=37SBMyGoCAU

I was wondering this - I 've been following this blog but have been lazy at reading up on his background. I found his posts on the manufacturing/electronics culture/subculture around Shenzhen fascinating...

not to mention the regular posts on odd circuit boards....

Re: Building my Own Laptop

#36

Post by Ives »

pasbesoin wrote: post #33

Don't know whether this fits, but here's something I'd like from the power system: Automated battery maintenance. I'm plugged in, a lot, and I forget to / blow off periodically cycling my battery. (Admittedly, maybe I'm unusual / an edge case, in this, and my thoughts here are of little general value.) I'd like a power system that can be made to periodically and contextually select to run from battery, even while plu…

Only what you're suggesting isn't actually battery maintenance. In fact, it will decrease the capacity of your battery (by as much as a normal drain-recharge cycle of course).

Cycling the battery will however appear to improve the capacity by recalibrating the internal circuitry. That's still somewhat useful to a user, but much less than battery maintenance would be.

PS: From what I understand this only applies to modern Li-Ion batteries, if you're using different battery technology your mileage may vary. Some battery technologies do benefit from being periodically cycled.

Re: Building my Own Laptop

#37

Post by TerraHertz »

JDuMond wrote: post #20

It's great to see that dedicated hackers can get their hands on the hardware and data-sheets needed to design and manufacture these kind of high performance projects. There still remains one huge barrier before we'll see a large number of projects like this: the costs of the equipment used to validate the signal integrity on high speed digital systems like this immense. I'm hoping that soon enough Moore's law will wo…

Actually it's been easily possible for years. Just forget about buying new equipment and buy older Tektronix or HP sampling scopes on ebay. For eg the HP 54121T, a 20GHz scope with TDR, able to characterize trace impedance absolutely workably for modern motherboard applications. I got a perfectly functioning one on ebay for $600. Also you can get the service manuals, which you can't for more recent equipment.

Re: Building my Own Laptop

#38

Post by pasbesoin »

Ives wrote: post #36
pasbesoin wrote: post #33

Don't know whether this fits, but here's something I'd like from the power system: Automated battery maintenance. I'm plugged in, a lot, and I forget to / blow off periodically cycling my battery. (Admittedly, maybe I'm unusual / an edge case, in this, and my thoughts here are of little general value.) I'd like a power system that can be made to periodically and contextually select to run from battery, even while plu…

Only what you're suggesting isn't actually battery maintenance. In fact, it will decrease the capacity of your battery (by as much as a normal drain-recharge cycle of course). Cycling the battery will however appear to improve the capacity by recalibrating the internal circuitry. That's still somewhat useful to a user, but much less than battery maintenance would be. PS: From what I understand this only applies to mo…

Maybe I'm not up to speed on the latest developments, but I currently have two laptops whose batteries have essentially been reduced to short duration UPS's.

I should be more pro-active, but I forget, or I worry that I'll discharge right before I need to be charged up. And one sits on a spare table, doing its thing all by itself, much of the time.

They tend to stay plugged in and on overnight. It would be nice if, e.g. once a week or so -- whatever's best for the battery at hand -- the power system could run a discharge /recharge cycle "in the middle of the night" or similar.

In my experience, batteries still have memories (that shrink over time and with lack of cycling), and from what I read periodic cycling is the solution.

If Bunnie can find an acceptable fuel cell option, of course I'm all for that. ;-)

P.S. I think I do at least partway understand what you're saying, that being that rechargeable batteries have a limited number of cycles and tend to loss capacity with increasing cycle count.

However, in my case, it appears to be a lack of cycling that is catching up with me well before the above does.

Re: Building my Own Laptop

#39

Post by caublestone »

This is incredible. In a time where it seems the big pc designers are shifting appeal to the facebook heavy consumer market, developers need a new source. Id love to see this snow ball into open source phones, tablets, glass etc. and an open ubiquitous wireless network.

Re: Building my Own Laptop

#40

Post by revelation »

dshep wrote: post #26
jacquesm wrote: post #24

This is an absolutely awesome project, mad props to the guy for envisioning it and pulling through. The cost must work out to something terrible but I can totally see why someone would do this. Having an FGPA on there is a very clever idea, it adds flexibility to the design in a way that a prototyping area would but much cleaner. The one corner with all the PWM and other connectors is the most interesting part, I rea…

Kind of old but there is one, http://andrew.huang.usesthis.com/

What a refreshing attitude. Someone with no emotional connection to his operating system.
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