Autonomous downhole control methods and devices

摘要

Autonomous control of a wellbore tool is provided by programming a memory module of a processor with a database having data relating to a selected parameter of interest; conveying a sensor and the processor along the wellbore; and activating the wellbore tool if the processor determines that a measurement provided by the sensor correlates with the database data. The processor may correlate the sensor measurements with a predetermined pattern associated with the data, a preset value, and/or a preset range of values. Well tool activation may occur when the processor finds: a substantial match between a predetermined pattern and at least one measured value; a present value and at least one measured value, and/or a preset range of values and at least one measured range of values. Also, activating the well tool may occur only if a measurement from a second sensor meets a preset criteria.

主权项

1. A method for activating a tool at a selected location in a wellbore drilled in a subterranean formation, comprising:
measuring a parameter of interest using a formation evaluation tool that investigates the formation surrounding the wellbore, wherein the measured parameter of interest characterizes the selected location in the drilled wellbore; programming a memory module of a processor with a database having pre-existing data relating to the parameter of interest; conveying a sensor and the processor to the selected location along the drilled wellbore, the sensor configured to measure a parameter of interest relating to the pre-existing data by investigating the formation surrounding the wellbore; monitoring a measurement output of the sensor using the processor in the wellbore while the sensor is being conveyed along the wellbore; determining whether the location in the drilled wellbore has been reached by using the processor in the wellbore to correlate the measurement output of the sensor with the pre-existing data in the database; and transmitting a signal to a wellbore tool using the processor in the wellbore if the processor determines that the location has been reached.