Abstract: A drill control system includes an uphole control device and a downhole control device. The uphole control device is configured to transmit a reference trajectory to the downhole control device and receive information about an actual trajectory from the downhole control device. The downhole control device is configured to receive the reference trajectory from the uphole control device, measure the actual trajectory, correct deviations between the reference trajectory and the actual trajectory, and transmit information about the actual trajectory to the uphole control device.

Abstract: The instant invention provides apparatus and methods for directional drilling. One embodiment of the invention provides a drill control system including an uphole control device and a downhole control device. The uphole control device is configured to: transmit a reference trajectory to the downhole control device and receive information about an actual trajectory from the downhole control device. The downhole control device is configured to: receive the reference trajectory from the uphole control device, measure the actual trajectory, correct deviations between the reference trajectory and the actual trajectory, and transmit information about the actual trajectory to the uphole control device.

Abstract: Steering behavior model can include build rate and/or turn rate equations to model bottom-hole assembly behavior. Build and/or turn rate equations can be calibrated by adjusting model parameters thereof to minimize any variance between actual response 118 and estimated response produced for an interval of the well. Estimated position and orientation 104 of a bottom-hole assembly along a subsequent interval can be generated by inputting subsequent tool settings into the calibrated steering behavior model. Estimated position and orientation 104 can be compared to a well plan 106 with a controller 108 which determines a corrective action 110. Corrective action 110 can be converted from a build and/or turn rate to a set of recommended tool settings 114 by using an inverse application 112 of the steering behavior model. As additional data 118 becomes available, steering behavior model can be further calibrated 102 through iteration.

Abstract: Steering behavior model can include build rate and/or turn rate equations to modal bottom-hole assembly behavior. Build and/or turn rate equations can be calibrated by adjusting model parameters thereof to minimize any variance between actual response 118 and estimated response produced for an interval of the well. Estimated position and orientation 104 of a bottom-hole assembly along a subsequent interval can be generated by inputting subsequent tool settings into the calibrated steering behavior model. Estimated position and orientation 104 can be compared to a well plan 106 with a controller 108 which determines a corrective action 110. Corrective action 110 can be converted from a build and/or turn rate to a set of recommended tool settings 114 by using an inverse application 112 of the steering behavior model. As additional data 118 becomes available, steering behavior model can be further calibrated 102 through iteration.

Abstract: Steering behavior model can include build rate and/or turn rate equations to modal bottom-hole assembly behavior. Build and/or turn rate equations can be calibrated by adjusting model parameters thereof to minimize any variance between actual response 118 and estimated response produced for an interval of the well. Estimated position and orientation 104 of a bottom-hole assembly along a subsequent interval can be generated by inputting subsequent tool settings into the calibrated steering behavior model. Estimated position and orientation 104 can be compared to a well plan 106 with a controller 108 which determines a corrective action 110. Corrective action 110 can be converted from a build and/or turn rate to a set of recommended tool settings 114 by using an inverse application 112 of the steering behavior model. As additional data 118 becomes available, steering behavior model can be further calibrated 102 through iteration.

Abstract: A method for drilling a borehole, comprising transmitting a directional signal to a downhole processor, and maintaining the desired drill bit azimuthal direction by using the downhole processor to evaluate an actual drill bit azimuthal direction relative to the desired drill bit azimuthal direction, and using the downhole processor to adjust the actual drill bit azimuthal direction by controlling the directional drilling device.

Abstract: An actively controlled rotary steerable drilling system for directional drilling of wells having a tool collar rotated by a drill string during well drilling. A bit shaft has an upper portion within the tool collar and a lower end extending from the collar and supporting a drill bit. The bit shaft is omni-directionally pivotally supported intermediate its upper and lower ends by a universal joint within the collar and is rotatably driven by the collar. To achieve controlled steering of the rotating drill bit, orientation of the bit shaft relative to the tool collar is sensed and the bit shaft is maintained geostationary and selectively axially inclined relative to the tool collar during drill string rotation by rotating it about the universal joint by an offsetting mandrel that is rotated counter to collar rotation and at the same frequency of rotation.