A sister organization run by friends of Open_Sailing is doing this kit. Might be useful for us at some point :) ?
This kit was created as a means to improve the georeferencing of images captured using balloon mapping. This kit is based around the open-source Arduino mircocontroller. Utilizing a GPS receiver, barometric sensor, three-axis accelerometer and data logger, this module allows for the synchronization of data with images captured from a Canon camera running the CHDK. By utilizing the USB remote function of the CHDK software the camera can be triggered in sync with the logging of the sensor data.
Along with the georeferencing capabilities, this kit captures the position of the camera in relation to the ground plane. This is done by capturing the x/y rotation of the camera with the accelerometer.
Sample log data:
Arduino code available here
Here is a quick test of image rectification using the accelerometer data.
We are considering using this method to write this information into the EXIF for each image.