I've always fancied doing a little project with a min-itx board (see http://www.mini-itx.com).
Now that I'm sat here bored with a broken arm from last weekends race at Oulton Park I decided to go ahead and order one along with a small 7in touch screen.

While most people put computers in cars as media centres, my idea is to use the computer in my locost build instead of dials and warning lights, and give 0-60 times etc. (I could use digi-dash or similar but I like to do things the hard way!!) If I get that far I'll look at adding more interesting things such as camera's and on-board engine diagnostics etc.

I'll be using linux booted off compact flash and writing the display software in java (boot time will be an issue but I'll worry about that later!).

I now have one major problem, and that is that I know very little about electronics, and the IO boards I have found cost a fortune! I need to acquire data from:
- Speedo sensor (magnetic switch?)
- Voltage sensor for: revs, indicators etc
- Switch sensors for: warning switches (oil pressure/brake fluid etc)
- Resistance sensor for: fuel level etc

Can anyone help point me in the direction of a reasonably priced IO board that will give me what I need, or any electronic circuits I could build? (Or is this a daft idea and should I just build a juke box for the wife instead?)

Cheers,
Sam

I have also looked at that for some time.

The thing that i worry about is the hard drive. What happens when the car hits a bump??

Spanner in the works warning!

I'm guessing you've gone for something like a Lilliput 7" touchscreen?

It's totally unsuitable for use as dials etc, it's not waterproof and also not sunlight readable. I've tried using one in sunlight and it's just not possible, the display becomes too washed out.

This is something I've been giving serious consideration to for a while now. Maplin do a USB IO board which has useful things like analogue inputs etc:

http://www.maplin.co.uk/Module.aspx?ModuleNo=42857&criteria=EXPERIMENT/PROGRAMMER%20KITS&doy=4m11

And you can add a number of them together to get more ports.

One drawback, though, is a requirement to call a DLL, which may rule out the possibility of using Linux? Although there may be clever ways round that.

Chockymonster has a good point re sunlight, but it may be possible to recess the display into the scuttle a way to shade it and protect it from rain?

I'm not yet at a point in my build where I'm worrying out dials, but I'd be very interested to hear how you get on with this.


Micael, as sammy was saying, you can boot off a large flash drive. Provided you get the solid state drives (I think some have mini HDs in them) you'll have no moving parts.


[Edited on 4/11/06 by bilbo]

One of my colleagues at work was talking about a version of Windoze that is very very cut-down the other day. Trouble is I can't remember what he said it was used for. Something like public access info terminals and cash point machines I think but I'm still racking my brain to try to remember.

Anyway, the point is that it was so lightweight that it could reside in flash memory and you may be able to run standard Windoze applications. That way you'd have more scope with what you could interface with and the language chosen to write the user interface. I'll see if I can get a little more info about this version.

It would certainly be very cool to have a touch screen for control functions. Totally virtual switchgear and the like.

quote:

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Originally posted by bilbo
This is something I've been giving serious consideration to for a while now. Maplin do a USB IO board which has useful things like analogue inputs etc:

http://www.maplin.co.uk/Module.aspx?ModuleNo=42857&criteria=EXPERIMENT/PROGRAMMER%20KITS&doy=4m11

And you can add a number of them together to get more ports.

One drawback, though, is a requirement to call a DLL, which may rule out the possibility of using Linux? Although there may be clever ways round that.

Chockymonster has a good point re sunlight, but it may be possible to recess the display into the scuttle a way to shade it and protect it from rain?

I'm not yet at a point in my build where I'm worrying out dials, but I'd be very interested to hear how you get on with this.


Micael, as sammy was saying, you can boot off a large flash drive. Provided you get the solid state drives (I think some have mini HDs in them) you'll have no moving parts.


[Edited on 4/11/06 by bilbo]

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quote:

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Originally posted by chockymonster
Spanner in the works warning!

I'm guessing you've gone for something like a Lilliput 7" touchscreen?

It's totally unsuitable for use as dials etc, it's not waterproof and also not sunlight readable. I've tried using one in sunlight and it's just not possible, the display becomes too washed out.

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Just found out about the lightweight Windoze... It's Windows 98 Lite and it's basically an ultra cutdown Win98 without Internet Explorer v4. I've not looked into it fully but it may be able to be run from some kind of flash memory setup and because it's Windows you could write your own interface. It may be a step too far in terms of hardware interfacing though.

Just found a link... http://www.litepc.com/

[Edited on 4/11/2006 by andyd]

For your interface issues I recomend looking at the picaxe system....Im pretty sure you can use that to control a serial input to a PC....I have used it in the past but never to feed data back to a PC...

Dunc

My Subaru Forester 2.5xt has a good touchscreen in it. Maybe you could find one of these off a crashed one?

quote:

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Originally posted by sammy
Yes it is a lilliput screen, but as bilbo says I'll try recessing it to give some shade/protection. If can I get the project to work as intended I'll look at getting a better screen, although it seems near impossible to find an industrial quality one at a sensible price! (especially considering how cheap lcd telly's are)

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http://tomshardware.co.uk/2005/09/09/windows_in_your_pocket/

Flash drive will be fine, according to this you can run windows off a 256mb drive, as for programming java. you really do like doing things the hard way(God i have working with java i would do it in VB but thats just me).

good idea though, always fancied building a small PC with an ITX.... but i could never find a reason to need a small PC

Oh ya if u want a quicker boot look in to the SD cards photographers use, cant remeber the brand name but they have the quickest access time so should speed boot up a bit

John
[Edited on 4/11/06 by JackNco]

[Edited on 4/11/06 by JackNco]

If you get it working, you could also install a cheap Infra-Red Webcam and have a really cheap night vision system of the type that's only just getting put into very expensive production cars.

im going to be using megajolt for ignition, always thought it might be possible to have the laptop in the car for datalogging as it reads revs, etc
your idea is a step further but sounds top.....if i ever get the build to theat point!!

les

I built a car PC for my Alfa last year with a 7" Lilliput. It all worked well but to be honest my brother set up all the gubbins for me, (I don't understand what you lot are talking about above) I just built the thing and incorporated it into the car. The Lilliput does really need shading as said already because of the glare on the screen and to be totally honest, having experienced it myself and spoke to loads of others on the forum I frequented, I'd steer away from Lilliput. Very unreliable and kinda fragile inside. This site helped me no ends when I was building. Hope it helps you.

For an OS that will support DLL's why not use windows PE, its been popular for years as a DR boot disc OS, try googling "Windows PE" or "Bart PE" and as long as you have an XP CD to hand its FOC!!....but maybe not strictly legal........

For an OS that will support DLL's why not use windows PE, its been popular for years as a DR boot disc OS, try googling "Windows PE" or "Bart PE" and as long as you have an XP CD to hand its FOC!!....but maybe not strictly legal........

wandered about this as well but maybe pda route (widows mobile 2003 ) and visual basic. Not so much for dials but taking the output from my vems ecu.

The vems has a nice output to 4 line 20 chr lcd display (temp, rpm, lambda, ect) but thinking more for logging the data and possibly feed a bullet cam in to play back vidio and overlay the data.

early days yet but i am sure its possible.

regards

Agriv8

How's your German? Some good info here

Also a good little touch screen here

[Edited on 4-11-06 by RazMan]

Wikipedia is my friend...
http://en.wikipedia.org/wiki/Carputer
Look at the bottom of the page for links and forums.

Via Nano....

quote:

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Approximately the same size as a penny and less than half the size of the IntelŪ PentiumŪ M processor, the VIA Eden-N significantly reduces required board real estate, enabling smaller, more highly integrated platforms such as the 12cm x 12cm VIA EPIA N Nano-ITX mainboard.

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I am building one for my tin top that I use for work all the time. Mostly setting it up for navigation and obd11 diags. Tiny xp or xp beast work very well and beast is very very fast compared to regular xp-- its been cut down for gamers basically - the fact that it does not need activation does not hurt either.. I am running a ibm p3 800mhz and it boots to i guidance in around 40 seconds from a cold start. If just a reboot it only takes about 20 secs.
Still trying to decide on a 7-8 inch touch screen or try and find a 10 -12 lcd with vga in and use a track ball.
Dale

Win 98 lite is not what is used in Kiosks etc. they wouldn't be up for more than about 30 seconds if they did!

XP embedded (AKA Win Xpe) is generaly used for these kind of applications. There are embedded versions of linux available as well.

That said, I don't think runing instrumentation and media/GPS on a single heavyweight operating system is a good idea. Apart from the frustration of waiting 20 seconds or so for the system to boot everytime you start your car, there is always the risk of the system crashing due to a badly behaved application and bringing the system to a standstill. Despite what Linux advocates may say, I have seen Linux brought to it's knees just as often as XP.

IMO important stuff like instruments should be on a separate embedded system using a proper real time operating system (RTOS) or preferably no operating at all.

I'm slowly working around to putting a gumstix http://www.gumstix.com into mine, primarily to talk to accelerometers. It'll then use bluetooth to talk to the UI which will run on a Nokia 770.

in fact there should be the option.. to standby...
(allot faster boot) or to only shutdown the video / TFT.. and just let the system oen..

also IBM does hDD wich are realy shock proof...

saying that its still fragile..

Tks