Patent ID: 8690260

Claim:
An improved automated coal mining system, comprising: a rotating cutterhead drum fitted with bit blocks and replaceable bit picks; a set of strain gauges configured to measure a series of mechanical forces experienced by at least one replaceable bit pick mounted to a bit block on a cutterhead drum for operation during coal cutting; and a resonant microwave patch antenna (RMPA) mounted on a top surface shoulder of the bit block and configured to take impedance measurements of a coal face having a boundary layer of rock; the improvement comprising: a smart coal cutting drum processor connected to the RMPA and set of strain gauges, and configured to calibrate said impedance measurements according to strain gauge indications that a replaceable bit pick has encountered a boundary layer of rock, wherein the rotating cutterhead drum is thereafter enabled to automatically avoid encountering boundary layer of rock again because calibrated impedance measurements are available to provide a warning signal.