Write up of notes from summer 2013 about locating unmarked graves with ground-penetrating radar. There might be some other uses for this, including amateur archaeology.
Why is this interesting?
For a long time, Quakers were buried without headstones. Which means that many Quaker meeting houses doesn't know which areas around the building have people in them, and which don't... which becomes an issue every time Quakers want to expand buildings.
What's the research question?
How do you detect the potential presence of underground objects (hopefully objects that are 6 feet underground) or ground disturbances with DIY equipment? The UK TV series "Time Team" uses ground-penetrating radar for this: could we DIY-build similar equipment?
What's the discussion
Existing work includes http://minibnzreprap.blogspot.com/2012/09/ground-penetrating-radar.html
Mathew Lippincott suggested "The normal route would be to use a "knocker" and a series of geophones to get a picture of the ground using reflection seismology. I have no idea if there is accessible software to help with this. the hardware isn't too expensive though: https://www.sparkfun.com/products/11744"
Spike suggested using aerial photography: disturbed ground affects surface vegetation (http://en.wikipedia.org/wiki/Cropmark) in UV and IR imagery (he also noted that these effects are seasonal).
Shannon linked to http://publiclab.org/notes/eymund-diegel/11-9-2012/raising-dead-grassroots-mapping-helps-look-america-s-first-veteran-s-c and http://publiclab.org/notes/christenmcnamara/2-26-2013/balloon-mapping-test-flight-riverside-cemetary-22513
Jeff Warren suggested Eric Wolf's thesis on necrogeography with balloons http://www.nwmissouri.edu/library/theses/WolfEricB/WolfThesis.pdf but noted that the thesis focused on spatial accuracy, not identifying sites.
MIT's Open CourseWare has a tutorial on homemade radar http://ocw.mit.edu/resources/res-ll-003-build-a-small-radar-system-capable-of-sensing-range-doppler-and-synthetic-aperture-radar-imaging-january-iap-2011/, and some success has been achieved using cheap USB TV-receiver dongles as software defined radios http://sdr.osmocom.org/trac/wiki/rtl-sdr which may be suitable.
There is a project on hackaday where they launched a collaborative project to create a $500 ground radar system which looks promising. https://hackaday.io/project/4440-open-ground-penetrating-radar One of the concerns about sand mines in Wisconsin is that there are many Native American burials, especially along the Mississippi. No good mapping of the graves and mounds exists.