[Discuss] possible use case for hacked WiFi accessible SD cards/(Federico's talk on July 15th)

[Bill Bogstad]

I went home after Federico's talk yesterday and tried to come up with
some possible use cases for hacking the Linux running on the WiFi
accessible SD cards.   One issue with using these devices is that
there doesn't seem to be an easy way to add sensors/external controls
to the device.   There is an onboard serial port, but many sensors
don't do serial output.   On the other hand,
there ARE some rather cheap and interesting devices that do.   For
example, this hackable web page:

http://www.instructables.com/id/8-GPS-Receiver-Hack/

talks about using an $8 GPS receiver with an Arduino.   Normally, it
is used via a mini-PCI-e interface, but it turns out that
it also has a serial port to which an Arduino can communicate.   It
seems likely that this could be interfaced with the serial port
on a WiFi-SD card as well.   By combining the WiFi-SD card and the GPS
receiver, a cheap device could be created to log position
information which could then be retrieved via WiFi.   Plant it on some
one's car once and you never have to touch the vehicle again
to retrieve the logged tracking information.

For a more benign use case, add a rechargeable battery and solar cell
and it might be useful for naturalists who want to monitor the coming
and goings of animals in the wild.   Admittedly, there might be issues
of range on the WiFi connection here; but a directional antenna on the
data retrieval system might be sufficient.   If there are frequently
used game trails/watering holes, just set up your retrieval system
near one of them and retrieve the newest logs whenever the the animal
passes by that location.  In the local urban area, where "xfinitywifi"
SSIDs are common, you could let the device use your Comcast account to
upload the logs whenever it happens to see a strong WiFi signal.   If
you have it log whatever SSIDs it sees during its travels, you might
not even need a GPS
receiver.   I think Android devices can use the SSIDs they see to
retrieve coarse grained location information and if you can get access
to the same database, you might be able to do figure out location
information without the GPS.

Does anybody know of other cheap sensors which happen to have serial
ports included?  If a device is dealing with digital
data, having a serial port for testing seems to be a very common
practice; so I seems likely that others exist.

Of course once you add external devices, you are going to have higher
power requirements; but it still might be manageable...

Bill Bogstad