Abstract: A drill string device configured to operate at a down hole location in a well bore toward a location proximate the surface of an earthen formation includes one or more motors and/or a capacitor bank. The drill string device may be in fluidic communication with a drilling fluid. A first motor of the one or more motors may be operated as part of processing the drilling fluid. A first electrical energy may be provided to the first motor at least as the first motor is operating. A signal to stop the first motor may be received and/or the first motor may be stopped. A second electrical energy may be received from the first motor at least as the first motor is stopping. At least some of the second electrical energy may be directed to the capacitor bank.

Abstract: A rotary pulser and method is disclosed that includes a housing, a stator supported by the housing, a rotor adjacent to the downhole end of the stator, and a motor assembly coupled to the rotor. A controller may receive a signal that includes drilling information. In response to receiving the signal, the controller causes the motor assembly to rotate the rotor in a first rotational direction through a rotation cycle. The rotation cycle a) rotates the rotor from a first position, where the rotor does not obstruct the at least one passage, into a second position, where the rotor obstructs the at least one passage, and b) rotates the rotor from the second position to a third position in the first rotational direction. Rotation of the rotor generates a pressure pulse in the drilling fluid.

Abstract: A system for damping vibration in a drill string can include a magnetorheological fluid valve assembly having a supply of a magnetorheological fluid. A remanent magnetic field is induced in the valve during operation that can be used to provide the magnetic field for operating the valve so as to eliminate the need to energize the coils except temporarily when changing the amount of damping required. The current to be supplied to the coil for inducing a desired magnetic field in the valve is determined based on the limiting hysteresis curve of the valve and the history of the magnetization of the value using a binary search methodology. The history of the magnetization of the valve is expressed as a series of sets of current and it resulting magnetization at which the current experienced a reversal compared to prior values of the current.

Abstract: A rotary pulser and method is disclosed that includes a housing, a stator supported by the housing, a rotor adjacent to the downhole end of the stator, and a motor assembly coupled to the rotor. A controller may receive a signal that includes drilling information. In response to receiving the signal, the controller causes the motor assembly to rotate the rotor in a first rotational direction through a rotation cycle. The rotation cycle a) rotates the rotor from a first position, where the rotor does not obstruct the at least one passage, into a second position, where the rotor obstructs the at least one passage, and b) rotates the rotor from the second position to a third position in the first rotational direction. Rotation of the rotor generates a pressure pulse in the drilling fluid.

Abstract: A system for damping vibration in a drill string can include a magnetorheological fluid valve assembly having a supply of a magnetorheological fluid. A remanent magnetic field is induced in the valve during operation that can be used to provide the magnetic field for operating the valve so as to eliminate the need to energize the coils except temporarily when changing the amount of damping required The current to be supplied to the coil for inducing a desired magnetic field in the valve is determined based on the limiting hysteresis curve of the valve and the history of the magnetization of the value using a binary search methodology. The history of the magnetization of the valve is expressed as a series of sets of current and it resulting magnetization at which the current experienced a reversal compared to prior values of the current.

Abstract: A system for damping vibration in a drill string can include a magnetorheological fluid valve assembly having a supply of a magnetorheological fluid, a first member, and a second member capable of moving in relation to first member in response to vibration of the drill bit. The first and second members define a first and a second chamber for holding the fluid. Fluid can flow between the first and second chambers in response to the movement of the second member in relation to the first member. The valve assembly can also include a coil for inducing a magnetic field that alters the resistance of the magnetorheological fluid to flow between the first and second chambers, thereby increasing the damping provided by the valve.

Abstract: A system for damping vibration in a drill string can include a magnetorheological fluid valve assembly having a supply of a magnetorheological fluid, a first member, and a second member capable of moving in relation to first member in response to vibration of the drill bit. The first and second members define a first and a second chamber for holding the fluid. Fluid can flow between the first and second chambers in response to the movement of the second member in relation to the first member. The valve assembly can also include a coil for inducing a magnetic field that alters the resistance of the magnetorheological fluid to flow between the first and second chambers, thereby increasing the damping provided by the valve.

Abstract: A preferred embodiment of a system for rotating and guiding a drill bit in an underground bore includes a drilling motor and a drive shaft coupled to drilling motor so that drill bit can be rotated by the drilling motor. The system further includes a guidance module having an actuating arm movable between an extended position wherein the actuating arm can contact a surface of the bore and thereby exert a force on the housing of the guidance module, and a retracted position.

Abstract: A preferred embodiment of a system for rotating and guiding a drill bit in an underground bore includes a drilling motor and a drive shaft coupled to drilling motor so that drill bit can be rotated by the drilling motor. The system further includes a guidance module having an actuating arm movable between an extended position wherein the actuating arm can contact a surface of the bore and thereby exert a force on the housing of the guidance module, and a retracted position.

Abstract: A preferred embodiment of a system for rotating and guiding a drill bit in an underground bore includes a drilling motor and a drive shaft coupled to drilling motor so that drill bit can be rotated by the drilling motor. The system further includes a guidance module having an actuating arm movable between an extended position wherein the actuating arm can contact a surface of the bore and thereby exert a force on the housing of the guidance module, and a retracted position.