I am considering a recreational project to survey a fairly wide area. I have a magnetometer-type instrument whose output is a variable voltage, and I would like to automatically map that voltage as I walk around the area. to do this, I need to record the voltage, and the latitude and longitude every n seconds.
I am envisaging a device (rPi) which is connected to a GPS for simple position fixing, and my magnetometer. it will write a line of data on each cycle to as ascii file so that I end up with something like:
this (or something very like) must have been done before, please can anyone give any pointers?
whilst I am not averse to making this my own project, the main drive behind the idea is to give some treasure-hunting objective to a family camping expedition. (rather than spending some quality time in the workshop!)
on reflection it seems not unlikely that this may be achievable with a smartphone and some existing app. the GPS accuracy does not need to be great.
would be interested to read any comments.