Train spotting (or tank spotting) how hard can that be?
Turns out, it's complicated: weight, space, power and processing capacity all effect accuracy and price.
Seems IBM is on to something with its' neuromorphic chip:

https://www.technologyreview.com/s/6...-tank-spotter/

They seem to need the contract in order to get the scale to production to make the chip economical. Cart? Horse?