US Patent 8672055 Automated directional drilling apparatus and methods

Methods and systems for drilling to a target location include a control system that receives an input comprising a planned drilling path to a target location and determines a projected location of a bottom hole assembly of a drilling system. The projected location of the bottom hole assembly is compared to the planned drilling path to determine a deviation amount. A modified drilling path is created to the target location as selected based on the amount of deviation from the planned drilling path, and drilling rig control signals that steer the bottom hole assembly of the drilling system to the target location along the modified drilling path are generated.