A drilling assembly assembly includes a hammer motor, a shaft, a driver, and a hammer (218). The shaft is operatively connectable to the hammer motor and rotated thereby. The driver is operatively connectable to the shaft, and includes a cam (such as guide channel 232) rotatable with the shaft and a fixed guide (such as guide pins 230) having a guide surface thereon. The cam is engageable with the guide surface and axially movable thereabout during rotation thereof. The hammer is operatively connectable to the driver and axially movable therewith, axially movable within the housing (215) independently from axial movement of the housing, and engageable with the bit to impart an impact thereto whereby the bit is hammered.

A drilling assembly assembly includes a hammer motor, a shaft, a driver, and a hammer (218). The shaft is operatively connectable to the hammer motor and rotated thereby. The driver is operatively connectable to the shaft, and includes a cam (such as guide channel 232) rotatable with the shaft and a fixed guide (such as guide pins 230) having a guide surface thereon. The cam is engageable with the guide surface and axially movable thereabout during rotation thereof. The hammer is operatively connectable to the driver and axially movable therewith, axially movable within the housing (215) independently from axial movement of the housing, and engageable with the bit to impart an impact thereto whereby the bit is hammered.

A downhole system includes a drill string having a drilling fluid flow channel and at least one turbine alternator deployed in the flow channel. The turbine alternator is configured to convert flowing drilling fluid to electrical power. A voltage bus is configured to receive electrical power from the turbine alternator and at least one electrical motor is configured to receive electrical power from the voltage bus. An electronic controller is configured to provide active control of the turbine alternator via processing a desired speed of the electrical motor to generate a desired torque current and feeding the desired torque current forward to the turbine alternator. The turbine alternator is responsive to the desired torque current such that it modifies the electrical power provided to the voltage bus in response to the desired torque.

A downhole system includes a drill string having a drilling fluid flow channel and at least one turbine alternator deployed in the flow channel. The turbine alternator is configured to convert flowing drilling fluid to electrical power. A voltage bus is configured to receive electrical power from the turbine alternator and at least one electrical motor is configured to receive electrical power from the voltage bus. An electronic controller is configured to provide active control of the turbine alternator via processing a desired speed of the electrical motor to generate a desired torque current and feeding the desired torque current forward to the turbine alternator. The turbine alternator is responsive to the desired torque current such that it modifies the electrical power provided to the voltage bus in response to the desired torque.

A electrical conveyance for downhole tools is disclosed. The electrical conveyance system may include an electrical power manifold, a drill string coupled to the electrical power manifold, a multi-conductor conduit extending through an interior of the drill string, and a stinger assembly extending from an exterior of the electrical power manifold to an interior of the electrical power manifold to couple the multi-conductor conduit to an electrical power source.

A method may include communicating a command into a wellbore from the surface. The method may include determining a command to be sent to a downhole tool, and translating the command into a message, the message including a sequence of codes. The method may include rotating the drill string substantially at the set point RPM for a predetermined duration and measuring the rotation rate of the drill string. The method may include identifying the received set point RPM and rotating the drill string consistent with a first code value of a first code of the message as encoded. The method may also include decoding the first code and rotating the drill string consistent with a second code value of a second code of the message as encoded. The method may also include decoding the second code, identifying the command from at least one of the decoded first and second code and executing the command.

A method may include communicating a command into a wellbore from the surface. The method may include determining a command to be sent to a downhole tool, and translating the command into a message, the message including a sequence of codes. The method may include rotating the drill string substantially at the set point RPM for a predetermined duration and measuring the rotation rate of the drill string. The method may include identifying the received set point RPM and rotating the drill string consistent with a first code value of a first code of the message as encoded. The method may also include decoding the first code and rotating the drill string consistent with a second code value of a second code of the message as encoded. The method may also include decoding the second code, identifying the command from at least one of the decoded first and second code and executing the command.

The present disclosure provides a drilling machine configuration and related method that avoids drilling mud from contaminating hydraulic fluid that flows through the drive system of the machine. The disclosed system and method provides a drilling mud anti-contamination system that requires infrequent service and a system wherein the service can be quickly and easily performed.

The present disclosure provides a drilling machine configuration and related method that avoids drilling mud from contaminating hydraulic fluid that flows through the drive system of the machine. The disclosed system and method provides a drilling mud anti-contamination system that requires infrequent service and a system wherein the service can be quickly and easily performed.

A downhole communication device includes a downhole tool implemented in a wellbore. A magnetic component is connected to the downhole tool and configured to generate a polarized magnetic field. The downhole communication device includes a means for modulating the polarized magnetic field of the magnetic component to encode a bit sequence into the polarized magnetic field.