Gain control for steering downhole tool

Abstract

Methods and systems for identifying a gain value for a steering operation are described. In one embodiment, a processor identifies a rate of penetration value for a downhole drilling tool, identifies a gain value based on the rate of penetration, implements the gain value in a steering operation of the downhole drilling tool, measures at least one of inclination angle and azimuth; and adjusts gain settings for future steering operations using an error feedback loop that considers the identified gain value and the measured at least one of inclination angle and azimuth.

What is claimed is: 
     
         1 . A method comprising:
 a processor identifying a rate of penetration value for a downhole drilling tool;   the processor identifying a gain value based on the rate of penetration;   the processor implementing the gain value in a steering operation of the downhole drilling tool;   the processor measuring at least one of inclination angle and azimuth based on readings from one or more sensors in the downhole drilling tool; and   the processor adjusting gain settings for future steering operations using an error feedback loop that considers the identified gain value and the at least one of the inclination angle and the azimuth.   
     
     
         2 . The method of  claim 1 , wherein identifying the rate of penetration value comprises receiving the rate of penetration value via downlinking. 
     
     
         3 . The method of  claim 2 , wherein the processor receives the rate of penetration with a pre-nudge command or with a steering command. 
     
     
         4 . The method of  claim 1 , wherein identifying the rate of penetration value comprises calculating the rate of penetration value based on data received from the one or more sensors. 
     
     
         5 . The method of  claim 1 , wherein identifying the gain value comprises calculating the gain value based on the rate of penetration. 
     
     
         6 . The method of  claim 5 , wherein calculating the gain value based on the rate of penetration further comprises:
 the processor receiving data from the one or more sensors to measure a trajectory of the downhole drilling tool;   the processor determining a difference in the measured trajectory of the downhole drilling tool from a desired trajectory; and   the processor transforming the difference into a steering force ratio necessary to correct the trajectory of the downhole drilling tool so that the downhole drilling tool implements the steering controls and follows the desired trajectory.   
     
     
         7 . The method of  claim 1 , wherein identifying the gain value comprises referencing a look up table to determine the gain value associated with the rate of penetration. 
     
     
         8 . The method of  claim 1 , wherein the steering command comprises a hold inclination and azimuth steering command, an automated inclination hold steering command, or another autonomous control feature steering command. 
     
     
         9 . The method of  claim 1 , further comprising receiving a tolerance value identifying an allowed deviation from a desired drill path via downlinking. 
     
     
         10 . The method of  claim 1 , wherein the error feedback loop comprises a proportional-integral-derivative controller configured to mitigate undershoot or overshoot in at least one of a desired inclination angle and a desired azimuth when implementing the adjusted gain settings for the future steering operations. 
     
     
         11 . A system comprising:
 a downhole drilling tool comprising one or more sensors; and   a processor in communication with the downhole drilling tool to steer the downhole drilling tool through a drilling path, the processor further configured to:   identify a rate of penetration value for a downhole drilling tool;   identify a gain value based on the rate of penetration;   implement the gain value in a steering operation of the downhole drilling tool;   measure at least one of inclination angle and azimuth based on readings from the one or more sensors; and   adjust gain settings for future steering operations using an error feedback loop that considers the identified gain value and the at least one of the inclination angle and the azimuth.   
     
     
         12 . The system of  claim 11 , wherein the processor is further configured to receive the rate of penetration value via downlinking to identify the rate of penetration value. 
     
     
         13 . The system of  claim 12 , wherein the processor is further configured to receive the rate of penetration with a pre-nudge command or with a steering command. 
     
     
         14 . The system of  claim 11 , wherein the processor is further configured to calculate the rate of penetration value based on data received from the one or more sensors to identify the rate of penetration value. 
     
     
         15 . The system of  claim 11 , wherein the processor is further configured to calculate the gain value based on the rate of penetration to identify the gain value. 
     
     
         16 . The system of  claim 15 , wherein the processor is further configured to:
 receive data from the one or more sensors to measure a trajectory of the downhole drilling tool;   determine a difference in the measured trajectory of the downhole drilling tool from a desired trajectory; and   transform the difference into a steering force ratio necessary to correct the trajectory of the downhole drilling tool so that the downhole drilling tool implements the steering controls and follows the desired trajectory.   
     
     
         17 . The system of  claim 11 , wherein the processor is further configured to reference a look up table to determine the gain value associated with the rate of penetration. 
     
     
         18 . The system of  claim 11 , wherein the steering command comprises a hold inclination and azimuth steering command, an automated inclination hold steering command, or another autonomous control feature steering command. 
     
     
         19 . The system of  claim 11 , wherein the processor is further configured to receive a tolerance value identifying an allowed deviation from a desired drill path via downlinking. 
     
     
         20 . The system of  claim 11 , wherein the error feedback loop comprises a proportional-integral-derivative controller configured to mitigate undershoot or overshoot in at least one of a desired inclination angle and a desired azimuth when implementing the adjusted gain settings for the future steering operations. 
     
     
         21 . A non-transitory machine-readable medium comprising instructions, which, when executed by one or more processors, cause the one or more processors to perform the following operations:
 identify a rate of penetration value for a downhole drilling tool;   identify a gain value based on the rate of penetration;   implement the gain value in a steering operation of the downhole drilling tool;   measure at least one of inclination angle and azimuth based on readings from one or more sensors in the downhole drilling tool; and   adjusting gain settings for future steering operations using an error feedback loop that considers the identified gain value and the at least one of the inclination angle and the azimuth.