Automated drilling optimization

An apparatus for drilling a borehole penetrating the earth, the apparatus comprising:

• a processor configured to:
• receive (i) drilling parameters as a function of depth used to drill one or more offset boreholes, (ii) rate of penetration using the drilling parameters for the one or more offset boreholes, (iii) any drilling dysfunctions that occurred using the drilling parameters for the one or more offset boreholes, and (iv) one or more lithologies as a function of depth for the one or more offset boreholes;
• identify those drilling parameters that correspond to at least one of (v) a rate of penetration (ROP) that meets or exceeds a selected ROP threshold for each input lithology and (vi) a minimum number of drilling dysfunctions or minimum magnitude of a drilling dysfunction to provide identified drilling parameters;
• correlate a borehole plan comprising a borehole path to be drilled and one or more assumed lithologies as a function of depth to the one or more lithologies of the one or more offset boreholes;
• a borehole survey sensor disposed at the drill string and configured to sense a location of the borehole being drilled including depth of the borehole, wherein the processor is further configured to update the borehole plan with as-drilled borehole location information sensed by the borehole survey sensor;
• and
• a drill rig configured to operate a drill string to drill the borehole according to the borehole path using the identified drilling parameters that provide at least one of the ROP that meets or exceeds the selected ROP threshold for each of the one or more assumed lithologies in the borehole plan and the minimum number of drilling dysfunctions or the minimum magnitude of a drilling dysfunction.