Abstract: The method for drilling includes extending a borehole from a surface location to a borehole end with a drill string having a bottom hole assembly with a drill bit. A surface sensor and a downhole sensor take measurements used to project borehole features, like the borehole end. The measurements are used to project the borehole end so that the drill bit can be steered through the rock formation. The downhole sensor is separated from the bit location by a plurality of segments. The method includes corrections when the measurements at the downhole location are not the measurements at the bit location. As the drill bit travels, the types of corrections change, including applying an initial Kalman filter, a first adjusted Kalman filter, a second adjusted Kalman filter, and a third adjusted Kalman filter, according to the plurality of segments between the downhole sensor and the bit location.

Abstract: The method for drilling includes extending a borehole from a surface location to a borehole end with a drill string having a bottom hole assembly with a drill bit. A surface sensor and a downhole sensor take measurements used to project borehole features, like the borehole end. The measurements are used to project the borehole end so that the drill bit can be steered through the rock formation. The downhole sensor is separated from the bit location by a plurality of segments. The method includes corrections when the measurements at the downhole location are not the measurements at the bit location. As the drill bit travels, the types of corrections change, including applying an initial Kalman filter, a first adjusted Kalman filter, a second adjusted Kalman filter, and a third adjusted Kalman filter, according to the plurality of segments between the downhole sensor and the bit location.

Abstract: The method and system for determining position with improved calibration allows a device to initiate activity at the proper location, such as navigating a drill bit through a rock formation. A pair of position sensors in opposite orientations generates position data signals. A temperature sensor detects temperature and duration of the temperature. An adjusted plastic bias value is determined by a processor module based on the temperature data signal, the duration of the temperature, and the position data signals so as to account for bias and hysteresis errors and error correction based on the opposing orientations of the pair of position sensors. A position value is set according to the adjusted plastic bias value so that the position value is more accurate. The activity of the terminal device is initiated or maintained according to the position value calibrated by the adjusted plastic bias value.

Abstract: The method and system for determining position with improved calibration allows a device to initiate activity at the proper location, such as navigating a drill bit through a rock formation. A pair of position sensors in opposite orientations generates position data signals. A temperature sensor detects temperature and duration of the temperature. An adjusted plastic bias value is determined by a processor module based on the temperature data signal, the duration of the temperature, and the position data signals so as to account for bias and hysteresis errors and error correction based on the opposing orientations of the pair of position sensors. A position value is set according to the adjusted plastic bias value so that the position value is more accurate. The activity of the terminal device is initiated or maintained according to the position value calibrated by the adjusted plastic bias value.

Abstract: The method and system for determining position with improved calibration allows a device to initiate activity at the proper location, such as navigating a drill bit through a rock formation. A position sensor having an oscillation element with a range of displacement in a set direction according to gravity generates a position data signal based on an amount of displacement in the set direction. A temperature sensor detects temperature and duration of the temperature. A plastic bias value is determined by a processor module based on the temperature data signal, the duration of the temperature, and the position data signal so as to account for bias and hysteresis errors. A position value is set according to the plastic bias value so that the position value is more accurate. The activity of the terminal device is initiated or maintained according to the position value calibrated by the plastic bias value.

Abstract: A method and apparatus for encoding and synchronizing and sequencing pulse encoded data in a pulse telemetry system. The time intervals between successive pulses in a pulse train are representative of the magnitude of the data parameters. Redundant pulses are included in the pulse trains at predetermined time locations with respect to the pulses so as to enhance the ability to recognize or distinguish data pulses over noise signals. Synchronization pulses are employed to enable identification of the particular data parameters even though one or more of the data pulses is obscured by noise. The sequence of the production of the pulse code signals is continuously monitored to enable the telemetering system to be activated promptly after a shutdown at the place in the train of data where it would be if the shutdown had not occurred.