8/22/08
Data Logger Thoughts...
Just saw a picture of a Wii Nunchuck (I think this is a wired accessory to the wireless (bluetooth) Wii game controller to allow two handed game play). I assume this part has a three axis accelerometer inside, which could make a very inexpensive G-force sensor for a data logger. This could easily be modified to work with my current data logging system.

Of course, this leads me to looking at updating my current logger system. The accelerometer that I built 5 years ago is still working well, though only single axis and just the chip cost was about $70 back then. I am guessing the newer chips are more accurate, and surely cheaper.

I noticed there are a few simple to use GPS chips as well, which could be used to plot time, location and speed. This would require a logger interface that would accept a data input rather than just a voltage level input as my current logger does.

I also now know how to use both SD cards and USB sticks for reading/writing data. This would be much more elegant than connecting serially to the logger for start / download of data as I do now.

This is just a reminder to myself to draw a few of these things up and make a board for such things. Code to do this is extremely easy and the cost is acceptable for the increased ease of use and increased functionality. If making a board, using the Wii thing makes no sense... as I'd just put a new accel. chip on the board.

*Remember to be sure to include an adc so I can still receive analog signals from 0-5v sensors....
*Add Push button start... and or start when data is constantly changing...
*Update every .0625 seconds... would be nice to be able to switch between fast log (1/16 sec) or slow log (.25 or .5 sec).
*Log for at least one hour, when 6 channels of data is being recorded.

Another Thought:
The wireless Wii handset should be able to be connected to a PC for logging of the accelerometer data wirelessly. This is of course very range limited, but if someone wanted to strap an old laptop into their car this could be made to work very cheaply as a G-force data logger.

On this same direction... why not (someone likely already has...) build an app for the Iphone to log forces and GPS (the iphone does have gps receiver right...?) data. The Ipod touch may also have both gps and accelerometers - which would be cheaper. Not something I would use, as I'd rather make my own allowing me to input analog signals as well... but nifty for someone that already has the Ipod or phone.