PC in a car

[bigben2k]

I've been pondering adding a PC to a car (another one of those old projects that keeps getting put off) and I've listed these requirements:

-connect to the OBD or OBD 2 onboard computer, and log performance data
-have a wireless connection to upload the data logs (automatically) to the home PC

optionals:
-communicate (voice / music) to another similarly equipped car
-a network port for a laptop
-control various parts of the car automatically (i.e. lights)
-act as a security system
-GPS
-MP3

The PC hardware is actually the easy part of the project. The hard part is the power supply! Anyone have any *cheap* ideas?

I've looked into DC-DC converters from Vicor, and now I'm looking into automotive PSU converter designs by TI (i.e. TPS40100)
http://focus.ti.com/docs/prod/folder.../tps40100.html
a Buck converter

Linear Tech's LTC3780
http://www.linear.com/pc/productDeta...2,C1116,P10090
a buck-boost controller

and I haven't been over Atmel, yet. ( atmel.com )

Otherwise there's a dude on eBay selling these:
http://cgi.ebay.com/ws/eBayISAPI.dll...tem=6824180729

[Joe]

hehe Ben, this isnt really the forum for it... I guess I can make an Automotive PC forum if you would like.

HTPC's = Home Theater PC

[Slipknot]

The M1-ATX DC-DC on Ebay isn't bad, but these guys make the best:

http://www.opussolutions.com/

[JoeKamel]

MP3Car.com forums are your friend. TONS of info there. Been lurking for about a year and a half and I'm getting ready to start my build, it's my xmas present to myself.

http://www.mp3car.com/vbulletin/

O'Reilly makes a decent book on the subject. Not necessarily the greatest resource, but for $15, its decently informative.

Some things I would talk about ruling out right now though:

Security system - your battery will NOT like you. You're going to have the pc running almost the entire time. There's a guy on the MP3Car forum named shotgunefx, he has a security vcr in his trunk, you may want to talk to him about that.
Vehicle control - depending on your software skills (I don't know enough to comment) its possible, it also depends on the kind of car you have.

Some general thoughts: There are schematics out there for DIY carpc power supplies that you can hardwire onto your car's 12V line, you can go power inverter, many options. Suggest you find out what kind of amperage your alternator can supply. With a 150W opus, you're drawing almost another 13 amps, make sure you have the space to play with. Being in Texas, you have to give a very long thought to cooling. I'm in the same boat as about 3 months a year, its too cold around here for a HDD to spin up safely until the car warms up. You're looking at frying your CPU unless you look at something to keep the PC from automatically booting until the AC takes over.


Joe: is it possible to move this thread to say Random Nonsense?


What kind of car are you planning the install in?

[superart]

Originally Posted by Joe

HTPC's = Home Theater PC

Hooptie Teathered PC

[PaulDriver]

Heck, I'm thinking about adding one to my '54 Studebaker 3r6 Pickup

Now, that's a challenge :P

P.D.

[bigben2k]

Originally Posted by Joe

hehe Ben, this isnt really the forum for it... I guess I can make an Automotive PC forum if you would like.

HTPC's = Home Theater PC

Yeah, I know it's a bit out there, but I though that if we'd talk about micro ATX PCs, why not this one?

Thanks for the replies guys.

My alternator can put out ~95 to 100 amps.
I've explored adding a second alternator (easier to do on a Studebaker), but not sure if it's necessary; it certainly isn't practical. I can swap out the alternator for a slightly more powerful one (for my Grand Am) with one for the V6 version; a 10% boost. Alternatively, I pulled out the power steering pump on my car, and have room for "something", except the exact same alternator.

Then I thought about adding a second battery, mounted in the trunk. Of course it would be charged by the same alternator (assuming that I'm not overloading anything), but leave it disconnected, as far as turning the engine over is concerned. In other words, isolate it from the rest of the car; I would then have a steady power source, without the drop out from cranking (which solves a lot of issues).

Yeah, the PC would be running all the time; it has to be on to transfer the data logs to the house anyways. I'll be looking for something that has a sleep mode, to reduce power consumption. Yeah I know, these things can take a battery down-and-out in less than 24 hours.

I'm trying to stay away from HDDs; like JoeKamel said, it has specific environmental (temperature, shock) requirements that I don't care to deal with. A flash disk looks promising. It's hot in Texas; it'll be hard enough to cool the motherboard alone.

The cars involved are a 93 Pontiac Grand AM, and an 01 Nissan Sentra, but the application should be pretty much universal.

[TerraMex]

JoeKamel: good site.

why not a laptop and a docking station, install it under the glove compartment ?

[bigben2k]

Not a bad idea, but I believe I'll have a smaller footprint with a scratch built solution, albeit no screen, but with more options (i.e. diskless).

There's also an issue of theft prevention; there's no sense in having something desirable in plain sight (even under the glove compartment).

[JoeKamel]

BB2K: You may wanna check the hitachi endurastar drives if you do want an HDD, otherwise go with a normal notebook and a manual on/off switch perhaps? Limiting yourself to like 4 gigs, not really the best option in the world.

As far as where to put it, thre's a lot to be said for your trunk if you're willing to do some nutjob wiring. Probably the most popular place after in dash. Looking at your dash, you may want to consider an in trunk job. OBD is going to be hit or miss for you because OBD-II wasn't required until I think 1995 or 1996. Up until OBD-II, the comm. protocols were pretty proprietary and limited. Check out what your car is and what you can do with the OBD its running.

As far as the alternator issue, howmuch do you think you have to spare? Like I said, a 150W Opus is going to eat about 13 of those amps, and if you have an audio system in there, that's probably eating a good deal of it as we speak. I don't know how much a higher amp alternator will run you, I know for my strat, it's going to run about $400, but it'll be worth it because there's a lot more electronics I'll be able to do.

[TerraMex]

Ok, in the glove compartment then .
wiring a small 5 or 7 " LCD screen then, in the dashboard, should prove easier.
besides, with a docking station, you can simply remove the laptop in 5 secs.

[greenman100]

I have over 600 posts at MP3car forums.

PSU: look into the DSATX
Screen: Liliput or Xenarc. I have a couple myself, PM me if you're looking to buy one.
Power: a car battery will power a low power board like a Via for about a day. Sleep mode is key.

[greenman100]

oh, as far as alternator, you're 100% fine.

my AMD based system only pulls 6 amps at 12v. if you can turn on your headlights, you've got plenty of juice.

[JoeKamel]

Greenman - I figured the alternator wouldn't be a problem, but I'm also looking at putting in a much beefier audio system. Not sure how I'm going to fit all of this, but hopefully....... Anyway, thanks for the tip on the DSATX when I saw the threads on MP3car I didn't see anything about a low temp. cutoff, this rocks for me during winter.

[TerraMex]

http://www.travla.com/
interesting.

[bigben2k]

Oh here's the source of how I came to revive this project:
http://eetimes.com/news/latest/showA...leID=174400347

Note the details of the setup (2nd battery).