A system for steering a drilling device comprising a drill pipe, is provided therein, the system comprising: a hoop sleeved on the drill pipe of the drilling device and having an outer diameter substantially equal to an inner diameter of a hole to be drilled; and a steering driving mechanism provided between the hoop and the drill pipe, for controlling a radial displacement of the drill pipe relative to a center axis of the hole to be drilled while drilling. The steering driving mechanism comprises one or more sub-mechanisms for connecting the hoop and the drill pipe and driving the drill pipe to move inside the hole, wherein each of the sub-mechanisms comprises an actuator adjustable in length, and a link element with one end rotatably coupled to the actuator and the other end rotatably coupled to hoop.

An example apparatus for controlling the direction of drilling a borehole includes an outer housing having non-uniform stiffness and an inner housing at least partially within and rotationally independent from the outer housing and having non-uniform stiffness, A drive shaft may be at least partially within the inner housing. At least one of the outer housing and the inner housing may include a tubular structure with at least one of multiple materials with different stiffness, and a portion with less structural material than another portion.

Aspects of the disclosure relate to a system including an implement (e.g., a steering tool, a drill bit) tetherable to an equipment string (e.g., a drill string), where the implement includes a steering mechanism to steer the equipment string with respect to a wall of a tubular passage (e.g., a borehole). The system can also include a bearing housing for the equipment string (e.g., connectable to a drill pipe of the drill string), where the bearing housing is rotationally coupled with the implement and rotated. The system can further include an actuation mechanism coupleable between the bearing housing and the steering mechanism to actuate the steering mechanism based upon a rotational orientation of the bearing housing with respect to the steering mechanism.

A rotary tool for operation within an underground borehole or within tubing in a borehole has a tool body and at least one sensor-containing unit attached to the tool body and positioned to contact the conduit wall. The sensor-containing unit includes an exterior portion to contact the borehole or tubing wall and one or more sensors is located in a cavity between the exterior portion and the tool body. The sensor-containing unit may be formed from the exterior portion, an attachment portion for attachment to the tool body, and one or more connecting portions extending between the attachment and exterior portions, with the sensor-containing cavity between the attachment and exterior portions. Possible rotary tools include drill bits, reamers, mills, stabilizers, and rotary steerable systems.

A method for causing a desired drilling direction of a steerable subterranean drill in consideration of a contemporaneously detected formation tendency force acting on a drill bit of the steerable subterranean drill. The method includes detecting, utilizing a steering direction setting device, a direction and magnitude of a formation tendency force acting on the drill bit of the steerable subterranean drill. Further the steering direction setting device is configured to contemporaneously cause the drill bit of the steerable subterranean drill to drill in the desired direction, counteracting the formation tendency force based on the detected direction and magnitude of the formation tendency force acting on the drill bit.

A rotary steerable drilling system includes a housing, a drive shaft passing through the housing, a shaft/housing locking mechanism disposed to selectively engage the drive shaft and the housing, and an anti-rotation mechanism disposed to engage a wellbore wall. Shaft/housing locking mechanism includes a first configuration in which rotation of the drive shaft is independent of the housing, and a second configuration in which rotation of the drive shaft causes rotation of the housing. Anti-rotation mechanism includes a first configuration in which the anti-rotation mechanism extends radially relative to the drive shaft, and a second configuration in which the anti-rotation mechanism retracts from engagement with the wellbore wall. A timing mechanism may be employed to transition the anti-rotation mechanism from the first configuration to the second configuration before the shaft/housing locking mechanism transitions from the first configuration to the second configuration.

A dual member drill string having a plurality of dual member drill string sections for use in horizontal directional drilling operations. Each drill string section having an outer member and an inner member that is rotatable independently of the outer member. The outer member has a pin end and a box end. The inner member has a pin end disposed within the pin end of the outer member and a box end disposed within the box end of the outer member.

In accordance with some embodiments of the present disclosure, systems and methods for a gain scheduling based toolface control system for a rotary steerable drilling tool are disclosed. The method includes determining a desired toolface of a drilling tool, calculating a toolface error by determining a difference between a current toolface and the desired toolface, determining a plurality of operating points of the drilling tool, selecting one of the plurality of operating points based on a current operating point of the drilling tool, determining a model based on the selection, calculating a correction to correct the toolface error, the correction based on the model, transmitting a signal to the drilling tool such that the signal adjusts the current toolface based on the correction, and drilling a wellbore with a drill bit oriented at the desired toolface.

Systems and methods for optical communication in a downhole tool are disclosed. An optical communication system includes a rotation-varying outer housing that is at least partially rotationally decoupled from an inner member. The inner member is at least partially disposed within the rotation-varying outer housing. The optical communication system also includes one or more transceiver modules, one or more transmitting bulbs rotationally coupled to one of the outer housing or the inner member, and one or more optical sensors rotationally coupled to one of the outer housing or the inner member. The transmitting bulbs are configured to transmit light over at least a portion of a cavity between the transmitting bulbs and the optical sensors, and the optical sensors are configured to receive light over at least a portion of a cavity between the transmitting bulbs and the optical sensors.

A drilling system may include an outer sleeve, and a rotary steerable module including a shaft extending within the outer sleeve. The rotary steerable module may further include bearings disposed within the outer sleeve and through which the shaft extends, and cams positioned along the shaft between the bearings. Each cam may include an eccentric ring through which the shaft extends. Each extension of the shaft through one of the eccentric rings defines a bend in the shaft within the outer sleeve, the bend having a bend angle. A method of use and a drilling control apparatus are also provided.