Learn how to fit a Personal Computer (PC) into a car or other vehicle.
Not only looks cool, but a CarPC can allow you to play your favorite music and videos, navigate to your destination, view live engine data, and lots more!Okay I admit it, I'm a geek! Having been brought up on way too much science fiction, a fond memory of my childhood was a fictional speaking computerized car named K.I.T.T. from the television series Knight Rider. It was with this spectacle in mind that I decided to fit a CarPC into my Mk1 MX5.
So what could be the benefits of fitting a PC (Personal Computer) into your car (or other vehicle)? Well the possibilities are endless; you could play your favorite music while on the go, hook up a GPS and use navigation software to get you to your destination, connect an OBDII reader into your car and get live engine information, tether to your mobile internet on your phone and surf the web, connect a USB FM radio dongle for digital radio on the go, the list goes on and on. A list of things I have tried appears at the end of this article, but I will leave it up to you what you want your own custom CarPC to do for you.
The image above shows my own CarPC as installed in my 1990 Mk1 MX5 (Eunos Roadster). It is running my own software (see the section below on Car Software to get your copy FREE), custom written to perform the various operations I needed in the car, but other software solutions are available to buy.
CarPC Initial Considerations
Some things to consider before we start building our installation are; desktop or laptop based, powering the system, viewing output and providing some kind of user input. There are multiple options to deal with each of these issues, the methods you employ yourself will depend on your own needs, available spaces in your vehicle and the desired use of your CarPC. My own requirements were met using the hardware shown below, where space in my little MX5 is seriously limited, and my intention was to see just how cheaply this task could be accomplished, E.g. a fairly strict budget and recycling as many parts as I had laying around..My CarPC Parts
Here is a list of the parts used in my CarPC installation, with more important parts explained in more detail afterwards.Lilliput 7" VGA Touch Screen
M2-ATX 12v PC Power Supply
EPIA-EK 8000EC Motherboard
40 Gb Tandata SSD ATA Hard Drive
USB Bluetooth Adapter
USB GPS Receiver
USB Wireless Network Adapter
USB IR Remote Control
200w Power Amplifier (with matched speakers!)
Various Extensions, USB Hubs and Audio Leads
Installation Summary: The 7" touch screen is mounted into a 2 DIN aperture in the dashboard, providing input and output for the motherboard (PC) located in the boot. When the ignition key is turned to the ACC position, the PC and screen are powered up and the CarPC boots (restores from hibernation for quick boot). Sound from the PC is routed into an amplifier before being routed to the car speakers. An IR remote control is used when the touch screen does not suffice (when entering text for example) and provides both keyboard and mouse functionality. A wireless Network adapter allows the PC to be tethered to a mobile phone in order to access the internet, and a GPS adapter provides real-time location data to navigation and mapping software. When the key is turned to the Off position, the PC gracefully hibernates, with all power to the system being removed around 30 seconds later to prevent battery discharge.
Power Supply
While researching these concepts I have tried laptops with car chargers, along with an inverter with a standard desktop power supply, neither of which are recommended. For the final build I chose an M2-ATX Automotive PC Power Supply to power a low powered motherboard. This power supply is wired, via a fuse, directly to the battery, with a third wire going to the ACC wire on the ignition switch. In addition to supplying the required power for my motherboard, it has a feature that essentially presses the power button for you, when you start the car, and again when the car is turned off. To speed up start-up times you can set your power button to initiate a hibernate state rather than a complete shut-down. After around 30 seconds the power is completely removed from the system to prevent battery discharge. The unit itself requires no fan, and was screwed to a piece of wood, alongside the motherboard and other components located in my boot.Display & Input
The 7" touch screen fits nicely into a 2 DIN hole in the dashboard and is fairly legible at 800x600 resolution. The touch screen provides simulated mouse inputs, and an Infra-Red Remote Control allows access to most other keyboard and mouse functions. A variety of mini-keyboards and other input devices are readily available, mi IR remote cost less than £10 from china and arrived within 2 weeks. There are even adapters available for a variety cars to allow some PC features to be controlled from your steering wheel or stalk mounted stereo controls.
Motherboard Etc.
The Car PC itself is made up of the power supply detailed above (left side of picture), an EIPA-EK motherboard (center of picture) containing a 800mhz Fan-less CPU and 2 Gb Ram. Has a MPEG decoder, 4 USB 2.0 ports, integrated sound and graphics, with a very small foot-print. Data is stored is a small 40Gb SSD hard drive, located under the ribbon cable in the top of the picture. In my opinion a Solid State Drive (SSD) type disk is essential as traditional "moving part" hard drives do not last very long with all the bumps that come along with the road, trust me on this!
Extra Parts
The sound output from a standard PC does not have sufficient power to drive a set of car speakers, and so it is necessary to pipe out output through an amplifier before sending it to the speakers. How powerful this amp is depends on how loud you want to hear your music, and the maximum power rating of your car speakers. I use a 200 watt power amplifier with a pair of 150 watt speakers mounted in my doors. The automotive power supply mentioned above contains an amplifier signal wire to turn the amp on, a few seconds after the system is powered up, to avoid any annoying audible "thump" in your speakers when you turn the system on.
Other hardware added to the system include wireless and Bluetooth networking adapters to allow for file access across devices, and a GPS receiver (shown above) to retrieve real-time location data for navigation software.
CarPC Hardware Installation
It is highly recommended that you fully test your in-car PC system "on the bench" to ensure everything, both hardware and software, is working as it should, before you attempt installation into your vehicle. Use a suitably high powered 12v power supply for indoor use. Once tested, create a wiring plan so that you know what cables need routing to what locations. Check that all leads will reach its final destination and obtain extension leads where cables are too short. When adding extension leads, try to use the shortest possible lead required to reach the final destination. Placing some insulating tape around extension "joins" can help prevent corrosion and stop them coming apart during installation.After installing the touch screen into the dashboard, and removing the center console, I had to run the following cables under the carpet and through a hole into the boot area; Display Power Lead, VGA Lead, Touch Screen USB Lead, Ignition ACC Power Lead, 2 x Stereo Speaker Leads (connected to speakers in dashboard harness).
The display power leads were connected to the 12v output of the automotive power supply, supply power only when the PC is on. The ACC wire connects to the power supply to indicate when the system should start-up/shutdown. The VGA lead and USB connector for the touch screen are plugged into the motherboard, in my case attached to a piece of wood that stands upright in a space towards the rear of the boot space next to my spare wheel. The speaker cables are attached to the stereo outputs on the amplifier (attached to the other side of my wood, facing outwards). The speaker output from the motherboards 3.5mm jack is connected, using the appropriate cable, to the amplifier stereo input sockets (usually Stereo Phono type sockets).
The GPS module in my installation has a magnetic base. I mounted it discreetly behind my seat-belt pillar, giving it a fair all-round view of the sky. Its USB connector was passed through the same hole in my parcel shelf as used by the other cables, and connected to a USB socket on the motherboard. The Wireless and Bluetooth dongles were placed directly into remaining USB sockets. You may need to add a USB hub if you run out of available sockets.
Finally, after checking all wiring and connections are secure, the power leads for the amplifier and the CarPC power supply are connected to the battery, via an inline fuse. Ensure any controls on your amplifier are set to minimum, and then start the car. The car PC should boot after 5 seconds of the engine running, turning it off before this time "aborts" the power up. Once booted the system can be shut down by turning off the engine and removing the key. Shortly after receiving a power-on signal the power supply will turn on the amplifier. Any sound output on the PC will now be heard through the car speakers (you may need to make adjustments to both the CarPCs output and the amplifiers out levels for best sound quality). Not quite K.I.T.T but we have a PC fitted into our car!
CarPC Software & Configuration
The first software item to consider is operating system. I have opted for Windows XP Pro as this will not kill off my 800 Mhz CPU or munch away at my 2 Gb RAM. This leaves my resources free for playing some music and a bit of navigation, it wont be landing and space shuttles. It was trimmed down, removing unnecessary programs and services, screen saver disabled, and its default shut-down set to hibernate for faster power-up times.For navigation I use Autoroute by Microsoft. It has some nice features including voice directions. It reads real time location data from a GPS device, sent via a virtual COM port created by the USB device.
For playing music you could opt for Windows Media Player or one of a number of alternative audio players. There are also CarPC "front-end" programs available that make access to your media files and other controls more touch screen friendly. These are often quite expensive and often a bit over-kill, wanting to take over your entire system. These systems also tend to be Database driven, leading to confusion if you wish to play a lot of media from removable storage such as flash drives or memory cards. For this reason, and because I wanted to make my CarPC truly custom, I wrote my own front-end program; AutoFi.
AutoFi was written based on my own needs, but I offer it FREE to anyone that may be able to make good use of it. Please feel free to Download AutoFi and use it in your own CarPC installation. Please note that I am unable to support this software, although I will try to answer any questions posted into the comments box at the bottom of this article.
Once installed this software will;
- Allow you to quickly play music files, and create playlists from any media located on an accessible drive.
- Large touch screen friendly media buttons for volume, play, skip, mute etc.
- Onscreen Analogue & Digital GPS Speedometer and Compass (GPS module required).
- System Controls; Shutdown / Restart / Run Program etc.
Things I Have Tried
Voice control sounds like a neat idea. Its available in Windows, just a quick training session to introduce it to your voice, associate some verbal commands with system commands and off you go. Until you say "Play". As my car computer spends most of its time "Playing" this feature seems broken and not very practical.Speed Camera Warnings: A program monitoring my GPS location against a database of known speed and traffic cameras. When a camera is within range an audible reminder of the speed limit is played. Very effective in keeping my licence clean. Search Google for Gatso Hunter to get started.
Connect a TV / FM card and watch TV or listen to FM radio while out and about. A great way to add "car radio" functionality to your CarPC.
Add a 3G or 4G Wireless Dongle for constant access to the internet, or use a Wireless Network adapter to tether to your mobile phone.
A Serial Switch Controller allows you to send commands down a serial port and activate a number of relays (switches). Useful for operating electronic devices right from your CarPC screen, such as mood lighting etc.
XPort is a software program that allows your CarPC to share your GPS data with multiple GPS enabled programs. This is basically a COM Port Replicator that allows me to map my GPS port to an additional 3 COM Ports, one for my GPS Speedometer, another for the Speed Camera Warning system, and a third for my navigation software.
An OBDII Reader can be connected between your cars OBDII Port and your CarPC to provide real-time data on engine performance, examine and reset engine fault codes and more.