A system for mining material in a seam under an overburden layer using a geological model map of a geological formation, including a desired drilling end point at a predefined position relative to a geological boundary between the overburden layer and seam. A drill controller controls operation of a drill drilling a blast hole. A sensor pack senses, while drilling the blast hole, blast hole drilling operation parameters; and feeds the sensed parameters in real time to the drill controller. A data storage module stores a geological model of the geological formation and sensed parameters data. A processor module generates a geological model map including the desired drilling end point and locates the drill bit position relative to the geological boundary and such end point. The drill controller drills to the desired drilling end point and causes the drill to stop drilling upon reaching such end point.

A system for mining material in a seam under an overburden layer using a geological model map of a geological formation, including a desired drilling end point at a predefined position relative to a geological boundary between the overburden layer and seam. A drill controller controls operation of a drill drilling a blast hole. A sensor pack senses, while drilling the blast hole, blast hole drilling operation parameters; and feeds the sensed parameters in real time to the drill controller. A data storage module stores a geological model of the geological formation and sensed parameters data. A processor module generates a geological model map including the desired drilling end point and locates the drill bit position relative to the geological boundary and such end point. The drill controller drills to the desired drilling end point and causes the drill to stop drilling upon reaching such end point.

A system and method for controlling a drilling tool inside a wellbore makes use of Bayesian optimization with range constraints. A computing device samples observed values for controllable drilling parameters such as weight-on-bit (WOB) and drill bit rotational speed in RPM and evaluates a selected drilling parameter such a rate-of-penetration (ROP) for the observed values using an objective function. Range constraints can be continuously learned by the computing device as the range constraints change. A Bayesian optimization, subject to the range constraints and the observed values, can produce an optimized value for the controllable drilling parameter to achieve a predicted value for the selected drilling parameter. The system can then control the drilling tool using the optimized value to achieve the predicted value for the selected drilling parameter.

A system and method for controlling a drilling tool inside a wellbore makes use of Bayesian optimization with range constraints. A computing device samples observed values for controllable drilling parameters such as weight-on-bit (WOB) and drill bit rotational speed in RPM and evaluates a selected drilling parameter such a rate-of-penetration (ROP) for the observed values using an objective function. Range constraints can be continuously learned by the computing device as the range constraints change. A Bayesian optimization, subject to the range constraints and the observed values, can produce an optimized value for the controllable drilling parameter to achieve a predicted value for the selected drilling parameter. The system can then control the drilling tool using the optimized value to achieve the predicted value for the selected drilling parameter.

Embodiments of a downhole drilling assembly generally include a rotatable lower drilling assembly, a rotatable upper drilling assembly, and a drill bit, wherein the upper drilling assembly contains a mud motor adapted for clockwise rotation of its stator and counter-clockwise rotation of its rotor, whereby the lower drilling assembly is rotatable in the opposite direction of the upper drilling assembly or maintainable in a non-rotating state. The apparatus further includes sensors adapted to continuously measure physical properties and/or drilling parameters and a mechanism for continuously transmitting information relating thereto to the surface.

Embodiments of a method for operating a downhole drilling assembly generally include continuously measuring physical properties and/or drilling parameters proximate the drill bit, continuously transmitting information relating thereto to the surface, and controlling rotation of a lower drilling assembly in a non-rotating state or in the opposite direction of an upper drilling assembly by varying drill string rotation.

Embodiments of a downhole drilling assembly generally include a rotatable lower drilling assembly, a rotatable upper drilling assembly, and a drill bit, wherein the upper drilling assembly contains a mud motor adapted for clockwise rotation of its stator and counter-clockwise rotation of its rotor, whereby the lower drilling assembly is rotatable in the opposite direction of the upper drilling assembly or maintainable in a non-rotating state. The apparatus further includes sensors adapted to continuously measure physical properties and/or drilling parameters and a mechanism for continuously transmitting information relating thereto to the surface.

Embodiments of a method for operating a downhole drilling assembly generally include continuously measuring physical properties and/or drilling parameters proximate the drill bit, continuously transmitting information relating thereto to the surface, and controlling rotation of a lower drilling assembly in a non-rotating state or in the opposite direction of an upper drilling assembly by varying drill string rotation.

A device for limiting the flow of drilling fluid through a section of drill string includes a body with a hole in the periphery. Flow enters the device through one axial end, at least a portion of the flow exits through the other axial end. Some of the fluid flow can be diverted through the peripheral hole. A spring-biased axial piston may have an approximately constant force throughout its range of travel. The piston moves axially in response to the changing fluid flow rate to enable a constant amount of flow exiting the axial end of the tool to be achieved while diverting away excess flow through the side.

A device for limiting the flow of drilling fluid through a section of drill string includes a body with a hole in the periphery. Flow enters the device through one axial end, at least a portion of the flow exits through the other axial end. Some of the fluid flow can be diverted through the peripheral hole. A spring-biased axial piston may have an approximately constant force throughout its range of travel. The piston moves axially in response to the changing fluid flow rate to enable a constant amount of flow exiting the axial end of the tool to be achieved while diverting away excess flow through the side.

Disclosed are methods, systems, and computer-readable medium to perform operations including: receiving real-time drilling data of a drilling operation of drilling a wellbore; using the drilling data to calculate at least one indicator of a tripping operation performed during the drilling operation; detecting, based on the least one indicator of the tripping operation, a drilling problem with the drilling operation; determining a corrective action to avoid or mitigate the drilling problem; and performing the corrective action to avoid or mitigate the drilling problem.

Disclosed are methods, systems, and computer-readable medium to perform operations including: receiving real-time drilling data of a drilling operation of drilling a wellbore; using the drilling data to calculate at least one indicator of a tripping operation performed during the drilling operation; detecting, based on the least one indicator of the tripping operation, a drilling problem with the drilling operation; determining a corrective action to avoid or mitigate the drilling problem; and performing the corrective action to avoid or mitigate the drilling problem.