Open Vehicle Monitoring System

The Car Module

The car module is the hard part. We require an extremely reliable and low-power module to fit in the car.
While it is relatively simple for a hobbyist to create one of these, the hard part is making a common
platform that a group of hobbyists can get behind, and to make it very high quality. Home-soldered
connections and US$100k electric cars don't go well together.

What we've done is take the foundational work done by fuzzy logic and others, to build a base platform module.
We've then negotiated with factories in China (we live just over the border in Hong Kong) to get this
professionally built.

The module plugs into the car DIAG port, which provides both power and a CAN bus connection that the module
can transmit/receive messages on.

The platform itself is based on a PIC18F2680 processor and SIMCOM GSM module. Factory built and assembled,
but based on an open source extendable architecture. You can either buy these modules pre-built, or build
your own. Any profits on the sale of hardware will got to charity.

The SIMCOM GSM module has the ability to send/receive SMS messages, as well as a built-in IP stack for
GPRS communication. It allows the module to talk both communication protocols with very little PIC software
required. We decided to use these modules (rather than USB modems) for reliability reasons, as well as
the SIMCOM built-in support for IP protocol.

The final version re-works the CPU+CAN board to be rectangular and fit as a plug-in piggy-back on the
SIMCOM module we've sourced. We've also re-worked the board layout to separate the CAN bus across a
cicuit-board divide (to keep the CAN signals very simple and physically separated from the rest of the
components). In the final version, we also extend the unused I/O pins of the CPU out on expansion pins
(to allow for such things as in-vehicle displays). It all fits in a small case, is extremely low power,
and has two LEDs for diagnostics and a windscreen / rear window stick-on GSM antenna for optimal
reception. Overall, the design is very elegant and extremely robust.

The in-car module can be configured to just be a passive listener on the CAN bus, but can also be an
active participant and transmit control messages onto the bus. It can even just relay CAN bus messages
over the Internet to the Server/App. It is very flexible and has enough RAM and ROM to do some interesting things.

Users can either follow the schematics to build their own compatible boards, or buy them pre-made from us.
We expect to be able to charge just US$99+shipping for pre-assembled in-car modules (the CPU+CAN controller
module, SIMCOM GSM module, car DIAG cable, housing box and GSM antenna). This is a non-profit endeavor,
with any profits inadvertently made being donated to charity.