Abstract: A computer-implemented method for drilling a curve section of a wellbore in a subsurface formation. The method comprises obtaining a curvature setpoint. The method comprises obtaining drilling process feedback from a drilling assembly drilling the curve section of the wellbore. The method comprises updating a scheduling parameter vector based on the drilling process feedback. The method comprises updating a controller, wherein the controller is configured with the scheduling parameter vector. The method comprises determining an error based on the curvature setpoint and the drilling process feedback. The method comprises inputting the error into the controller. The method comprises determining, via the controller, steering decisions based on the error and the scheduling parameter vector.

Abstract: A curvature cruise controller has been designed to maintain a desired curvature when drilling a curve section of a wellbore. The curvature cruise controller utilizes a model-based controller (such as an LQR controller) to generate steering inputs based on the desired curvature and attitude setpoints and real time measurements. The model-based controller is configured with a wellbore propagation model that characterizes the tool's response dynamics. The curvature cruise controller utilizes real time drilling operation parameters measurements to tune the model-based controller.

Abstract: A variety of methods, systems, and apparatus are disclosed, including, in one embodiment a method of steering a drilling bit including: determining at least one control command to a drilling system, wherein the control command includes a combination of one or more nominal control commands output from a feedforward controller and one or more control command error values output from a feedback controller operating in an error space; and directing the drill bit of the drilling system in the wellbore based on at least the control command to extend the wellbore towards a planned depth-based wellbore trajectory.

Abstract: A method and system for estimating a wellbore curvature. The method may include disposing a rotary steerable system (RSS) into a borehole, storing a real-time curvature estimation for the borehole in an information handling system, wherein the information handling system is disposed on the RSS, taking a first attitude measurement at a first sensor, and taking a second attitude measurement at a second sensor. The method may further include applying a filter to at least the first attitude measurement and the second attitude measurement to form a filtered measurement set, performing a curvature estimation with the filtered measurement set to form an estimated curvature signal, comparing the estimated curvature signal to a curvature set point to find a difference, and adjusting at least one operating parameter of the RSS based on the difference.

Abstract: A variety of methods, systems, and apparatus are disclosed, including, in one embodiment a method of steering a drilling bit including: determining at least one control command to a drilling system, wherein the control command includes a combination of one or more nominal control commands output from a feedforward controller and one or more control command error values output from a feedback controller operating in an error space; and directing the drill bit of the drilling system in the wellbore based on at least the control command to extend the wellbore towards a planned depth-based wellbore trajectory.