Abstract: A system and method that include receiving a drilling trajectory plan to drill an intended trajectory. The system and method also include analyzing the drilling trajectory plan and identifying a tool face orientation to drill the intended trajectory based on the drilling trajectory plan. The system and method additionally include identifying an uncertainly level associated with the tool face orientation based on a data structure storing uncertainty levels at different tool face orientations. The system and method further include determining a drilling plan based on the uncertainty level associated with the tool face orientation.

Abstract: A method can include receiving real-time data during a drilling operation performed by a drillstring that includes a mud motor and a bit characterized by an expected performance profile; determining actual performance of the drillstring based at least in part on the real-time data; predicting degraded performance of the drillstring based at least in part on the real-time data and a mud motor degradation model; and updating the expected performance profile based on a comparison of the actual performance and the degraded performance.

Abstract: A method includes receiving at least one drilling condition input from at least one sensor of a drilling rig, obtaining a first slide mode determination based at least partially on a rotational speed of a drill string, obtaining a second slide mode determination based at least partially on torque applied to the drill string, selecting one of the first or second slide mode determinations based on the at least one drilling condition input, determining that the drilling rig is in slide mode based on the selected one of the first or second slide mode determinations, calculating at least one steering parameter based at least in part on determining that the drilling rig is in slide mode, and executing at least one drilling operation based in part on the at least one steering parameter.

Abstract: A method for controlling a drilling trajectory of a downhole tool includes receiving a drilling plan for a downhole tool to drill a wellbore toward a target in a subterranean formation. The method also includes receiving a measured drilling trajectory of the downhole tool after the downhole tool drills a first portion of the wellbore using the planned drilling trajectory. The method also includes determining a state of the downhole tool based at least partially upon the planned drilling trajectory and the measured drilling trajectory. The state includes a difference between the planned drilling trajectory and the measured drilling trajectory, a level of control of a steering capability of the downhole tool, and a location of an end of the wellbore. The method also includes generating a working plan trajectory based at least partially upon the state of the downhole tool and the drilling plan.

Abstract: A computer-implemented method including receiving a steering command identifying a tool face orientation in which the steering command is expected to produce an intended steering response of an intended drilling trajectory. The method further includes receiving an actual steering response result of the steering command in which the actual steering response result identifies an actual drilling trajectory. The method further includes storing a dataset comparing the actual steering response result in relation to the intended steering response, determining an uncertainty level of the tool face orientation based on the stored dataset, and outputting a visual representation of steering response with the uncertainty level.

Abstract: A method for determining a total torque output at a drill bit includes receiving an on-bottom pressure and an off-bottom pressure. The method also includes determining a differential pressure based upon the on-bottom pressure and the off-bottom pressure. The method also includes receiving a surface torque. The method also includes determining a torque transmission coefficient based at least partially upon the differential pressure and the surface torque. The method also includes determining the total torque output at the drill bit based at least partially upon the differential pressure, the surface torque, and the torque transmission coefficient.

Abstract: A mud motor includes a rotor and a stator. Drilling fluid received by cavities of the mud motor drives the rotor to rotate within the stator. The rotor includes one or more rotor lobes extending helically and defining a rotor pitch. The stator includes two or more stator lobes extending helically and defining a stator pitch. The rotor and the stator together define a tapered profile of the mud motor that varies proceeding from a top end of the mud motor to a bottom end of the mud motor. At least one of the rotor pitch or the stator pitch vary as proceeding from the top end of the mud motor to the bottom end of the mud motor.

Abstract: A method, system, and computer-readable medium related to control of mud motors in drilling systems, of which the method includes measuring an eccentricity of rotation of a rotor in a stator of a mud motor using a rotor-position sensor, determining a torque of the mud motor based in part on the eccentricity, and selecting a fluid flow rate, a pressure, or both of fluid delivered downhole, through the mud motor, based in part on the determined torque.

Abstract: A computer-implemented method including receiving a steering command identifying a tool face orientation in which the steering command is expected to produce an intended steering response of an intended drilling trajectory. The method further includes receiving an actual steering response result of the steering command in which the actual steering response result identifies an actual drilling trajectory. The method further includes storing a dataset comparing the actual steering response result in relation to the intended steering response, determining an uncertainty level of the tool face orientation based on the stored dataset, and outputting a visual representation of steering response with the uncertainty level.

Abstract: A method can include receiving data for a bottom hole assembly of a drillstring and a drill plan; generating candidate trajectories using at least a portion of the data; generating drill command schedules for the candidate trajectories; ranking the candidate trajectories based at least in part on the drill command schedules; and outputting at least a top ranked candidate trajectory and its corresponding drill command schedule.

Abstract: A computer-implemented method including receiving a steering command identifying a tool face orientation in which the steering command is expected to produce an intended steering response of an intended drilling trajectory. The method further includes receiving an actual steering response result of the steering command in which the actual steering response result identifies an actual drilling trajectory. The method further includes storing a dataset comparing the actual steering response result in relation to the intended steering response, determining an uncertainty level of the tool face orientation based on the stored dataset, and outputting a visual representation of steering response with the uncertainty level.

Abstract: A method for conducting wellsite activities includes receiving measured sensor data collected by one or more sensors in a wellsite construction rig, determining a data quality of the measured sensor data based on a plurality of data quality dimensions, predicting predicted sensor data using a model, comparing the measured sensor data with the predicted sensor data, determining an uncertainty of the measured sensor data based at least in part on the data quality and the comparison, and selecting one or more workflows for implementation using the one or more sensors, the wellsite construction rig, or both.

Abstract: A rotor and/or stator dampening system includes a stator and/or rotor with a liner selected of one or more materials to achieve a desired dampening effect. In one implementation, a progressive cavity motor or pump includes a stator with an internal axial bore therethrough. The stator has a liner along an axial length thereof with an inwardly facing surface defining the internal axial bore therethrough. The liner has a plurality of axial sections with at least two of the plurality of axial sections being constructed of different materials. A compression resistant mechanism, such as a spring or spring-like device, is disposed within at least one of the axial sections of the liner. The progressive cavity motor or pump also includes a rotor that is disposed and is rotatable within the internal axial bore of the stator to form a moving chamber between the rotor and the stator.

Abstract: A system and method for operating a mud motor in a wellbore. The method includes running the mud motor into the wellbore. A threshold rate of a pressure increase over time is selected. A rate of a pressure increase over time is measured across the mud motor in the wellbore. A flow rate of a fluid being pumped into the wellbore is varied when the measured rate is greater than or equal to the threshold rate.

Abstract: A computer-implemented method including receiving a steering command identifying a tool face orientation in which the steering command is expected to produce an intended steering response of an intended drilling trajectory. The method further includes receiving an actual steering response result of the steering command in which the actual steering response result identifies an actual drilling trajectory. The method further includes storing a dataset comparing the actual steering response result in relation to the intended steering response, determining an uncertainty level of the tool face orientation based on the stored dataset, and outputting a visual representation of steering response with the uncertainty level.

Abstract: Rotor and/or stator designs and methods thereof to improve progressive cavity motor or pump durability. In one or more implementations, the rotor may have a variable outer diameter or variable stiffness along an axial length thereof. The stator may similarly have a variable inner diameter or variable stiffness, which may compliment or diverge from the variable outer diameter or variable stiffness of the rotor.

Abstract: A method, system, and computer-readable medium related to control of mud motors in drilling systems, of which the method includes measuring an eccentricity of rotation of a rotor in a stator of a mud motor using a rotor-position sensor, determining a torque of the mud motor based in part on the eccentricity, and selecting a fluid flow rate, a pressure, or both of fluid delivered downhole, through the mud motor, based in part on the determined torque.

Abstract: A method for determining a remaining life span of an elastomer in a motor. The method includes running a downhole tool into a wellbore. The downhole tool includes a mud motor having a rotor and a stator. At least one of the rotor or the stator includes, or is at least partially made from, an elastomer. A number of cycles before the elastomer fails may be predicted. A number of cycles during a time period may be determined. A change in a remaining life span of the elastomer over the time period may be determined, based upon the number of cycles before the elastomer fails and the number of cycles during the time period.

Abstract: A system and method for operating a mud motor in a wellbore. The method includes running the mud motor into the wellbore. A threshold rate of a pressure increase over time is selected. A rate of a pressure increase over time is measured across the mud motor in the wellbore. A flow rate of a fluid being pumped into the wellbore is varied when the measured rate is greater than or equal to the threshold rate.

Abstract: A rotor and/or stator dampening system includes a stator and/or rotor with a liner selected of one or more materials to achieve a desired dampening effect. In one implementation, a progressive cavity motor or pump includes a stator with an internal axial bore therethrough. The stator has a liner along an axial length thereof with an inwardly facing surface defining the internal axial bore therethrough. The liner has a plurality of axial sections with at least two of the plurality of axial sections being constructed of different materials. A compression resistant mechanism, such as a spring or spring-like device, is disposed within at least one of the axial sections of the liner. The progressive cavity motor or pump also includes a rotor that is disposed and is rotatable within the internal axial bore of the stator to form a moving chamber between the rotor and the stator.