>Now here's the big ask! I'd like to be able to miniaturize the logger
>such that it will fit into the insole (about 5 mm thick). Do you think
>that's possible? I'd also like to have some kind of short range RF link
>to download the data.


Technically possible.
You'll want Flash memory storage.
I'm not sure where technology is up to here in max size per IC (others here
will know) but certainly a few MB is not too hard to handle.
Power supply may be annoying. You could even consider piezo or other
generation of power from walking pressure but this is probably a development
task whereas the rest of what you describe is more a design and build - ie
the technology exists, it's just a matter of putting it together. You will
require TSOP or similar type packaging (ie almost invisibly small) and you
may have a challenge with breakage. maybe not.

It would probably be easier to connect the electronics in a small package
which eg is strapped to the lower leg and connected via a very light cable.
This would be less "natural" but may be a good way to start. Wireless links
twixt foot and leg are probably not feasible due to power constraints but
maybe so.

Wireless reading is easy once you've solved all the other engineering and
mechanical challenges.
Could be RF, IR, Capacitive or inductive (just for starters).

Sounds interesting. I'll be interested to hear more. If this thread
continues much longer than a better heading would help attract others who
may be interested. I only found it because it was the only new PICList
message at the time :-) (an unusual event).




regards



      Russell McMahon
_____________________________

>From other worlds - www.easttimor.com
                                www.sudan.com

What can one man* do?
Help the hungry at no cost to yourself!
at  http://www.thehungersite.com/

(* - or woman, child or internet enabled intelligent entity :-))