‘Sounds like something a robot the size of a vacuum cleaner could do. ‘
LOL! You tell me: The Unit would have to find the grave in one of hundreds of cemeteries up to 450 acres each, remove all obstructions to the stone including digging it out if it is buried as well as tilting, lifting or moving the up to 1200 lb stone, assess the free space on the stone with respect to the desired inscription, make any necessary changes to the order, lay out the inscription, cut the template, glue same to stone (first cleaning stone), patch the template then, with up to 150 lbs of media called staurolite sandblast the template @90lbs/185CFM (requires 3000lbs of compressor) while assessing the template surface for burning or lifting (one full second of which will blow a hole in the stone which will then require repair or a new stone), asses the depth of letters, remove template, remove glue from stone, place stone in original position if moved, replace any plantings previously removed, blow dust and staurolite from grave, grave stone, neighboring graves and stones. Repeat 8 to 10 times per day.
Sorry but all that’s pretty easy stuff. All the parts are already there, just nobody has put them together yet. And when they do the machine will be doing 20 to 30 cycles a day.