método e aparelho para perfuração automática de um furo de sondagem em uma formação de subsuperfície, e, mídia legível por computador

Apparatus and method for automated drilling of a borehole in a subsurface formation. In one embodiment, a method includes selecting at least one control variable. A drilling performance objective having a value that is influenced by drilling of the borehole using the at least one control variable is defined. A first interval of the borehole is drilled maintaining the at least one control variable at a first value. A second interval of the borehole is drilled maintaining the at least one control variable at a second value. A third interval of the borehole is drilled maintaining the at least one control variable at a third value. The third value is selected based on a comparison of the values of the drilling performance objective while drilling the first interval and second interval to a predetermined optimal value of the drilling performance objective.