A system includes an inspection robot having a plurality of input sensors comprising a plurality of magnetic induction sensors and configured to provide inspection data of an inspection surface, wherein the inspection data comprises electromagnetic (EM) induction data, and wherein the plurality of input sensors are distributed horizontally relative to the inspection surface; wherein at least a portion of the inspection surface comprises a ferrous substrate having a non-ferrous coating thereupon; a controller, comprising: an EM data circuit structured to interpret the EM induction data, and to determine a substrate distance value in response to the EM induction data; and a thickness processing circuit structured to determine a thickness value in response to the EM induction data, the thickness value comprising a thickness of the non-ferrous coating.