🚀 go-pugleaf

Hello, I've got a rather large project going and would like suggestions
from the net.  I have seen several postings related to automotive electronics,
but none are quite as in depth as what I would like.  My basic project is
a high tech system to control all the electric/onic functions of the car.

Note:  ALL ARTICLES ON THIS THREAD SHOULD CONTAIN "CARNET" IN THE SUBJECT
       LINE SO THAT UN-INTERESTED READERS CAN MAKE USE OF KILL FILES.

Please, no flames for how silly this may sound;  At this point I'm just
doing research and trying to learn some specifics about the idea.  The
basic scope of the idea is as follows:

To replace the entire wiring warness (control and sensing circuits) with
a network controlled by a central computer.  I've intentionally avoided
limiting information because I would like to see what the net can produce
that I would never have thought of.  The basic division of topics as
I see it are as follows:

1)  Central Computer:  Should be fault tolerant or at least able to fail
    in a graceful way.  I would like to see a multi-processor system.
    One processor is rather simple and runs all the time.  It would
    control the communications with the net and provide simply services
    like clock, alarm, diagnostics, and COPS (Computer Operation Properly
    System) to the primary computer.  The COPS computer should be as simple
    and reliable as possible.  The main CPU should be more powerful (say
    68000 class).  At the least, it should integrate the dashboard with the
    devices on the net.  At most, it could be a full computer with electronic
    maps and a GPS decoder (Global Positioning System).

2)  The network:  Should be very reliable in a noisy environment.  Optic
    Fiber would be nice, but perhaps not the best solution.  Topologies
    and protocols should be discussed.  I see a Star network with the
    Central computer having 8 point-to-point optic-fiber links.

3)  Power Supplies & Distribution:  Sort of speaks for itself.  The logic
    needs rock solid power, and the lamps and other electro-mechanical
    devices need a rough (raw battery?) supply.  Assume the cars alternator
    and battery is still used (no atomics please :-) though dual battery
    systems might make sense.  I assume that most people will be interested
    in 12 volt negative ground systems, though that isn't a restriction
    (make sure and say if you're writing about a different system)

4)  Network Devices:  These boxes would be mounted throughout the car and
    would act as the network terminals.  A basic system might consist of
    the optic fiber net discussed with each net device capable of driving
    8 or 16 devices.  One box in the trunk, one in the passenger compartment,
    and one or 2 in the engine compartment should do.  Note that most of
    the switching done in a car is simply for lights or other motor/coil
    type devices.  Switching technologies: SCR/BPT/MOSFET/Relay...  I
    would like some simple sensing on each driven line to determine if
    current is flowing (easy way to determine if a bulb is out).  The
    boxes might need a "power-down" mode in which everything is off, but
    sensing on a few contacts continues and can alert the COPS computer
    if the state changes (like for an alarm system).

5)  Audio Systems:  Perhaps the most important part (at least most likely
    to get implemented :-).   I would be interested in OEM type tuner
    modules that get fed +12vdc, a few digital signals (frequence, local/dx,
    and so on) and produce a left and right output (OK, an antenna input is
    needed).  I've got a portable (Sony) CD player to use, and it has a remote
    control jack so I can send it commands (other ideas welcome).  OEM type
    tape decks would be nice, but since they are rather mechanical, I doubt
    you could match the quality/functionality of an off-the-shelf Kenwood
    (pick your fav) with an affordable OEM unit (Again, I want something
    sort of like a floppy drive:  Give it signals and it starts/stops/and
    steps as you command, providing nice clean audio in return).  I want
    my big CPU to do all the stereo control.  

6)  Technologies:   CMOS/TTL...  linear/switching...  solid state/relay...

7)  Human Factors:  For the new dashboard layout.  Switch types, display
    types (LCD, LED, ELD, CRT).  Icons -vs- text labels...

7)  Legality:  How legal is it to drive a car on a public road with mods
    this extensive (Street Legal) ? - probably belongs in some other
    newsgroup, but interesting here anyway.

8)  Misc:  Neat new ideas for making this system useful, and not just a
    toy.  One idea is to have a short range (100 ft) transceiver attached
    to the antenna.  The system could monitor the signal until it got a
    'wake up' signal, then the xmitter would come alive.  This would allow
    a certain amount of easy info interchange to the car without a cable.
    (The car should keep a maintenance log, perhaps a database of names/
    addresses/phone numbers...)  I can come home after work, flip on my
    PC and update my car's databases with my PC's latest.  This might
    even go so far as to allow the car to warm itself up, if needed.

    What about cellular phones?  I've never even used one, but they could
    have a great deal of potential in such a system (again, anybody know
    of cellular phone modules with CPU type interfaces?)

References to related information or research will be gladly accepted.
Thanks for your time and attention - Dean Reece - deanr@sco.com