A method for determining the wear on a linkage of a ground drilling device includes detecting a bending load of the linkage. The bending load is used to carry out a service life calculation.

A method for determining the wear on a linkage of a ground drilling device includes detecting a bending load of the linkage. The bending load is used to carry out a service life calculation.

A wellbore assembly can include a completion string having a side pocket. A downhole device can be positioned within the side pocket of the completion string. The downhole device can have a first end sized and shaped for coupling to a tool for inserting and removing the downhole device in the side pocket while the completion string is positioned downhole in a wellbore. The downhole device can be an electronic device.

A wellbore assembly can include a completion string having a side pocket. A downhole device can be positioned within the side pocket of the completion string. The downhole device can have a first end sized and shaped for coupling to a tool for inserting and removing the downhole device in the side pocket while the completion string is positioned downhole in a wellbore. The downhole device can be an electronic device.

A downhole sensor system includes a first sensor package having a substrate, an integrated circuit chip mounted to the substrate, the integrated circuit chip including a processor, a transducer chip mounted to the integrated circuit chip, and a plurality of sensors configured to measure at least shock, pressure, temperature, and humidity. At least one of the plurality of sensors is mounted to the transducer chip such that a stack is formed at least from the substrate, the integrated circuit, the transducer chip, and the sensor. The plurality of sensors are in communication with the processor.

A downhole sensor system includes a first sensor package having a substrate, an integrated circuit chip mounted to the substrate, the integrated circuit chip including a processor, a transducer chip mounted to the integrated circuit chip, and a plurality of sensors configured to measure at least shock, pressure, temperature, and humidity. At least one of the plurality of sensors is mounted to the transducer chip such that a stack is formed at least from the substrate, the integrated circuit, the transducer chip, and the sensor. The plurality of sensors are in communication with the processor.

A downhole tool may include a high-voltage power supply disposed within a housing to transform input power to the downhole tool from a first voltage to a second voltage greater than the first voltage. The high-voltage power supply may include an array of capacitors, which may include multiple rows of capacitors. The rows of capacitors may be parallel with a symmetric cross section as viewed from an end of the array of capacitors. The high-voltage power supply may also include diodes electrically coupled to the array of capacitors.

A sensor element for a cutting tool, the sensor element having a hard portion having a working surface and at least one diamond crystal at least partially embedded in the hard portion, the at least one diamond crystal being arranged to generate a piezoresistive signal in response to the working surface engaging external material in use.

A system, such as a bottom hole assembly, having a central body (18), at least one hydrostatically-actuatable assembly (50) configured to extend radially outward from the central body (18), the hydrostatically-actuatable assembly (50) having at least one N piston body (76) exposed to hydrostatic pressure; a plurality of passive structures (54), each of which is: configured to extend radially outward from the central body (18); and circumferentially spaced from the at least one hydrostatically-actuatable assembly (50) and another one of the plurality of passive structures.

A system, such as a bottom hole assembly, having a central body (18), at least one hydrostatically-actuatable assembly (50) configured to extend radially outward from the central body (18), the hydrostatically-actuatable assembly (50) having at least one N piston body (76) exposed to hydrostatic pressure; a plurality of passive structures (54), each of which is: configured to extend radially outward from the central body (18); and circumferentially spaced from the at least one hydrostatically-actuatable assembly (50) and another one of the plurality of passive structures.