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12-volt Plexiglass Computer
zootjeff writes: "I am in the process of designing and redesigning a computer for my car. This machine is based on the Shuttle FV24 motherboard. I built a box that is 8 inches by 7.5 inches by 3 inches. I also designed and built my own custom power supply. This could be useful to people who want to take linux into their car. It is also useful for solar powered battery operations." He sent some pictures, too, of what the 2nd case looks like, an
overview, including (!) police report number (the 2nd revision was stolen), more on
the power supply,
and the third iteration.
It's already been done...
I don't use a DC powersupply though.
Just hook it up to the car radiator :D
;D
The ultimate in liquid cooling for AMD's
----- Whats wrong with this picture? http://www.revoh.org:1234/whatswrong
One potential concern I see, especially with a car-bound computer, is impact resistance (potholes shake the unit around) and short-circuit fire safety. If you try using Lexan or Calibre sheet (polycarbonate) you'll improve the impact resistance of your case dramatically, and, the fire-resistance.
Plexiglass is notorious for getting brittle with heat and light exposure, both of which will happen if they sit in your car every day under the hot sun. One good summer could really do a number to the unit.
-When going for broke, go for Ithaca!
Conceptual Art like this is a fine way of improving the drudgery of the commute, where millions in their identikit Fords and Fiestas wander soulessly to and fro' employment in cubicles, some of us are free, free to make our wild imaginations reality.
Is playing with an in car computer really the same tho? I'm all a-quiver at the talents of these techy types, but what actual difference does this in car computer make? None, really, it won't inflame the mind or create beauty, and this is the problem with modern tinkering. 1950's mobiles had flaming jet burners on the back, and we are adding little bits of silicon? Yuk.
Thankfully, when I moved to America I noticed that there is an even bigger car scene, and I would go to my local car improvement rally were it not for all the guns held by the police and contestants at such events, quite barbarous, in many respects.
I urge the modifiers of the utilitarian not to invent even more utility, but to improve and create an original aesthetic. Art is what is missing from our lives, in the modern age, not linux computers.
Maybe some sensors jammed into every nook and cranny of your engine, too, for data acquisition and observation.
Tie it into a GPS, put some big servos on your steering column and have it drive you back home when you're too drunk %-)
A feeling of having made the same mistake before: Deja Foobar
Thumbnails won't work, but you didn't need to see them.
If I actually owned CDs made in the past four years, I might just get a CD player for my car. But with Napster, Gnutella, and now kza (a Kazaa client for Linux), I've stopped buying MP3s. The more I thought about it, the more I realized that this idea had a ton of benefits:
Skip-proof - RAM's pretty cheap... Take a cheap computer and throw a gig of RAM in, and set a lot of it up as a ramdisk. Go over a bump with a CD, and you'll start skipping. (A hard drive would probably be worse...) But if your next ten songs, and the apps the system's using are all in RAM, unless the RAM physically pops out, you're all set.
Tons of space - I have less than a gig of MP3s... I know some nuts who have 10+ GB, but you can get a 40 GB drive for like $100 if you shop around. Access speed isn't too important if it's just being thrown into ramdisk.
Configurable - Can your CD player do Ogg Vorbis? Play other formats? Probably not. Nor could you, say, hack up a Perl script pull the MP3s out of a MySQL database and read the song title with Festival.
Again, I haven't actually tried this, but I'd really like to...
________________________________________________
suwain_2
Without being overly negative, and putting this fellow down for his ingenuity, I just like to say that if something's going to appear on /., maybe it should be a little more original. Dont get me wrong, its a well done project, however I've read countless articles resembling this... i.e. normal computer, HD, modified case, inverter(cough), etc.
/cdrom -name *.mp3 | mpeg123 blah blah, etc). This would help with the stability/mechanical robustness of the system.
Putting it practically, a whole motherboard and 32 meg ram, etc is all overkill just to decode mpegs, however I guess most people wouldnt know how to program a DSP chip, or implement an mpeg decoder.
But what is more interesting, and is a bit more ingenius, is having a mobo/cpu/ram/etc, but a custom power supply. Why convert 12 volts to 110/240(australia, etc) and then back down to 12? Also, running such a high-level os such as window$ is also overkill. I would suggest either a really small linux distro booting off a floppy, or maybe DOS. A linux distro (i.e. tinylinux) booting off a floppy would eradicate the need for a hard drive if you played cd's off cd's (which is possible, using automount and find
But again, well done to the author of this project.
-foxxz
Could you please pass the word to the rest of your auto-sculpture friends that you need to use a better water-resistant glue in attaching all that crap? Our first good rain happened a couple weeks ago and I ended up following one of those trash-heaps on wheels. The freaking doll heads were tumbling off of the top of that POS car that they were once attached to and hitting my windshield.
Talk about disturbing.
I can't get to the site right now.
It amazes me that you woudl 'build a custom power supply' and use an inverter. What a waste.
Does plexiglas have alot of static? Would need to be careful not to fry components. Also...cars tend to create alot of nasty electronic noise..in a plexi case there would be little shielding from this noise (or shielding of the noise generated by the computer) which can cause all sorts of problems.
-
Since its slashdotted, I can't see all the details, but folks have added quite a bit to the base mp3-carputer. If you get a full screen, and a GPS receiver, you can do in dash GPS, others have added movies, wireless internet, games, etc. All available on the fly. However, this is FAR from original as another poster pointed out. Check out MP3Car.com. There's a bulletin board and examples. These guys have been making DC-DC power supplies and plexiglass cases for a long time.
Has anyone actually put together a PC that will control fuel injection, ignition and/or ABS/traction control or what not? PCs are so cheap these days that it would be very cost effective to put together a real time Linux (perhaps BIOS-based?) box with a bunch of RAM for data logging... There would be extra CPU cycles for playing MP3s and what not as well. Hell, maybe hook up a GPS sensor and record mileage. While that GPS sensor is in there, you could interface with suspension components and plot pot holes for people. ABS goes off? Why not create a system that would find redundant ABS occurances and warn drivers of slippery road conditions? Air bag? Call the ambulance!
I'm sorry... Have I wandered?
Life is the leading cause of death in America.
Any alternative products to that X-10 remote? I don't want to contribute any money to them knowing it will just fund more of those annoying pop-up ads.
you're forgetting about the + and - 12v lines and all the + and - 5v lines. nothing a visit to mouser.com can't solve, but don't go hooking up ALL those lines to 12v negative ground..
Intelligent Life on Earth
But man, have you ever got to lose the Def Leppard!
:-)
Curb CO2 emissions: Kill yourself today!
Around the middle of the article he mentions why he chose windows, and at the bottom he lists what the system costs, but said nothing about Windows licence.
Wondering what the thiefs that stole his first stereo were thinking though, and how good they were at writing bat files?
-- Another senseless waste of fine bytes.
Most of us have seen nifty hardware setups with nice looking cases. However, I am much more interested in custom software to make a car computer more customized.
/., of a Macintosh based system like that - pretty darned cool. Combined with a wireless access card (too bad Ricochet went under) of some sort, it could be somewhat useful for an internet connection. GPS would be simple. Add a wireless ethernet card so when you park in your garage you can access your wireless hub/network (if you have the money to put a computer in your car you can afford a wireless hub). This would make transferring mp3s and other files nice. Perhaps download some web pages for offline reading, a bunch of cool games (and emulated games), and a few joysticks and you'd have a pretty cool entertainment center for the car.
Anyone who has owned or used a power inverter or more demanding electronics in a car knows that you really can't run it (for long) when the engine is off. An inverter will automatically shut itself off and turn itself on when the input voltage fluctuates (a sign that the engine has been turned off).
Since the input voltage is only 12 volts, a easy battery backup could be implemented to allow the computer to run while the car is off. When the battery gets low, the computer automatically suspends or hibernates.
Obviously, these things are already present in every laptop. If I were to construct such a device for my car, I would probably use the laptop as the CPU and connect an LCD screen and monitor/mouse combo (wireless, probably) to it externally. Since laptops have one input voltage, you only need to build a single car adapter (or buy one).
In addition, plexiglass isn't shielded like the average metal case - you'll get more interference, especially noticable in a sound system.
I'd like to see setups of a small LCD touch screen that allows the user (preferably the passenger - drivers shouldn't be messing with computers while driving) to easily navigate through things. I think I have seen one such example, perhaps from
So, in conclusion, a laptop is an easier (if less creative) choice that is superior to most home-built CPUs, and the peripherals and software is the real place to be creative and innovative.
"The universe seems neither benign nor hostile, merely indifferent." --Carl Sagan
Every automobile manufactured since 1990 or so has a computer in it. Your gas pedal really does not control gas flow directly; instead it is a potentiometer that sends a signal to a computer. Some cars even use specialized PowerPC chips. The operating systems cars use are highly stable; blue screens of death in vehicles really could mean death. I know someone who had a car computer failure while on the highway; trust me, it isn't something you want to go through.
Anyways, IANAL, but note claims #1-7 all relate to claim #1, which requires the device in question to "control operation of components in the vehicle." As long as your device does not do anything that could be considered controlling how the vehicle directly operates (speed direction, etc.), you likely are fine. #8 describes many vehicles with multiple processors interconnected. The "client" could be as simple as the warning lights on your dashboard.
#9-#19 all point to #9, which matches what existing vehicles do. A "support" module could be a sensor, a "faceplate" module could again be warning lights on the dashboard, and the "computer" module could be the car engine controlling processor. #20 again requires a "vehicle related" application; I again read this as needing to be something critical to the operation of the vehicle that it could not function without.
If MS can prove to a court that MP3 players, radios, etc., are "vehicle related" just because they *might* be used in a vehicle, I'd just appeal by asking the judge if celluar phones are "vehicle related." These devices often are multi-function, etc., need to be made cheap, and if MS went after the cell phone manufactuers, we might actually see a good legal fight.
Quick overview: uses a DSP to decode at up to 256kbps in 18-bit. Has 4MB RAM, of which 1.1MB is used for the OS and software. Has a remote control interface. Takes 8 seconds to boot. Uses 35W of power. Has a custom power supply.
I think that this is much more interesting that the standard PC based one described above!
a) CAJUN - Linux-based car (or rack stereo) MP3 player. Includes plans for powering remote LCD panel from serial port. Replace a 5.25" bay cover on a 1U case with an LCD panel, and put 802.11 in the PCI slot, and it's great in a stereo system. Some people do IR input with LIRC for album/song/genre selection and start/stop. Someone gave me a RaQ4 which is a great case, but no PCI slot for sound or PC Card slot for the 802.11.
:)
b) get another StarTAC to share my minutes with as a rolling dial-up for things like checking movie times or raising/lowering the thermastat, setting the vcr, and feeding the cat via Misterhouse
c) I'd use a 12v power supply in the car, but be sure to power it through a special adapter that powers up the computer after 8 seconds (to avoid that weird power fluctuation between first turning the key and starting the car) and sends a "ups shutting down" signal but continues to power the PC for 30 seconds after the car is powered off.
d) can't forget the 802.11. I've also considered putting a crossover RJ45 on or near the dash for my laptop, but with the 802.11, I can do some "war driving" every time I get in the car not to mention the typical remote updating.
Intelligent Life on Earth
$5 / month hosted VPS on linux = awesome!
On my fv24 XFree86-4.1.0 locks the machine up tight as soon as I start it. Maybe I'm doing something stupid (besides running X, that is.)
Is it just me, or does this box remind anyone else of the computer "Orac" from Blake's 7
;-)
Ok, so it is just me then
crazy dynamite monkey
"but for many people, and even in aisle signs in hardware stores, Plexiglass = Lexan"
.40cal round at it. If you survive, try it again with Lexan. You will see the difference, trust me.
These "people" you refer to must be pretty dense. Lexan is nothing like plexiglass. Wanna test that theory? just sit behind a 1" thick piece of plexi and have a friend fire a
I am become Troll, destroyer of threads
an afternoon of experimenting, a halfway decent multimeter and a few trips to Radio Shack you can make a quality power supply for just about anything
This used to be true back when all power supplies were the linear "big brick of iron + 4 diodes" variety. However a proper switch-mode supply is not that easy to build (and Radio Shack is unlikely to sell the specialty transformers, high-frequency FETs, low-ESR capacitors, and inductor cores that you need; heck, they hardly even sell transistors these days).
You could do it with a few next-day deliveries from Digi-Key, an oscilloscope, an AC isolation transformer (to limit the damage when something fails on the "hot side" of the circuit), etc. However you might just end up paying the $$ for a nice Omron or similar industrial power supply. One with a UL/CSA rating too, so it doesn't start a fire that your insurance won't cover.
Note that I'm not saying you shouldn't build a power supply if you're interested in that sort of thing (and the ARRL handbook does have some good examples). Just make sure you're doing it because you want to do it, not just because you want to have a power supply.
Nonsense. We cut the stuff with band saws and dremel tools. They only cut things with a10" skil saw. Sheesh.
The standard solvent adhesive for "plexiglas" acrylic is methylene chloride. $10 a pint if I remember. It's water-thin and you need to have a good seal between the pieces, but a little practice and it works well. You can also wick it onto a set joint and capillary action will fill the voids in a second coat (keep it positioned exactly - enough of a second try can loosen the first). It's nasty stuff - comes in metal cans.
Not surprised Homer doesn't have this stuff - small hardware stores might - I seem to rememer seeing it in a Sears Hardware specialty store. We have a plastics specialty warehouse in CT.
I used to build custom rodent cages for our lab the same way. Do some dry runs - if you can boil water, you'll find the shortcuts and get good at this. I have a see-thru laser that's lasted nearly 30 years made like this.
"Win treats sysadmins better than users. Mac treats users better than sysadmins. Linux treats everyone like sysadmins."
I've done small projects with plexiglass before, and had great success cutting the stuff with a Dremel tool. I use a cutting wheel and very patiently cut along a line which I have previously drawn on the plexiglass. It's cumbersome, and very hard to make straight cuts longer than a couple inches, but it works. You might have success using the Dremel's jigsaw adapter. Using a couple C clamps and some scrap lumber, you may even be able to fashion yourself a mill which you can use to make straight cuts.
Be VERY careful about clamping the Dremel tool to a table, however. Make sure it's secure as hell and there's no possible way for it to slip. Zip ties might be useful for this.
As far as bonding plexiglass goes, I've never done it with glue, but aquarium glue works pretty darned well. If you're not too picky about how the finished product looks, epoxy should work well too.
I wonder if this could be related to my Humanities professor's comments?
"Reading the Odyssey translated is like making love through plexiglass. You can see what you're doing but it just doesn't feel right!"
** "You can compute through plexiglass...**
Men believe what they want. - Caesar
Put this stuff into a metal box where it belongs. (You will notice that Apple puts their computers into shielded metal boxes, even when the outside is plexiglass.)
Leaving aside the lack of RF shielding, it's been my experience that getting near plexiglass makes my hair stand up... that stuff holds one hell of a static charge! Wouldn't it just get continually worse if you fill it with electronics? If I'm right, this guy's box doesn't have much of a shelf life...
Whatever happened to JonKatz?
I know that one thing that you can do would be to mount it on a support system with rubber mounts/straps to absorb any huge jars to the car, that might be an idea worth exploring.
I am ALL ABOUT trying to set up one of these in my car but I really don't know where to start. Anyone have any links/ideas to help?
If God gave us curiosity
That'd be a pretty horrible idea, since the liquid in your car's coolant system can hover around 80C, which is far in excess of the temperature your CPU puts out.
The better idea would be to put a bigass heatsink and route airflow from the outside over the heatsink... Pushing air at 60MPH over your heatsink will be sure to cool it down in a hurry!! =)
If God gave us curiosity
There are plenty of regulators out there that are in little 3 pin packages (voltage in, voltage out, ground). Their sole purpose is to convert on DC voltage to another. Now, I don't know much about the current capability of these things but I'm sure that with a proper heat sink they can drive a fairly large load.