A method for directional drilling including defining, by a sliding mode controller, a sliding hypersurface for reducing a trajectory error in one or more error dimensions; determining a current trajectory error between a current trajectory of a directional drilling tool and a reference trajectory for a curved path, the current trajectory error corresponding to a current error position in the one or more error dimensions; calculating a sliding mode vector originating from the current error position and substantially conforming to the sliding hypersurface in the one or more error dimensions; determining a feedback control input for the directional drilling tool based on the sliding mode vector; instructing the directional drilling tool to generate a wellbore path according to the feedback control input; and updating the current trajectory error based on either a change in position or a change in attitude of the directional drilling tool.
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