Downhole perforation tool

Abstract

A downhole perforation drone includes a body comprising a material configured to dissolve over time. The body includes a first portion and a second portion. The first portion includes one or more sensors to determine a depth and position of the drone within a wellbore, a communications system configured to exchange wireless signals with a surface device, a perforation charge circuit to cause perforation charges to ignite, and a microcontroller to perform operations, including causing the perforation charge circuit to ignite the perforation charges. The second portion includes a plurality of perforation charges, the plurality of perforation charges to ignite upon receiving an instruction from the perforation charge circuit. The microcontroller can determine the position of the drone within the wellbore from sensor information and automatically instruct the perforation charges to ignite based on the position of the downhole perforation drone within the wellbore.

1 . A downhole perforation drone comprising:
 a body comprising a material configured to dissolve over time, the body comprising:
 a first portion comprising:
 an on-board sensor suite to determine a depth and position of the downhole perforation drone within a wellbore, the on-board sensor suite comprising a global positioning system (GPS), a casing-collar locator (CCL), and a gamma ray tool, 
 a communications system configured to send wireless signals to and receive wireless signals from a surface device, 
 a perforation charge circuit to cause perforation charges to discharge, and 
 a microcontroller to perform operations, the microcontroller preprogrammed with a target perforation area for creating perforations in the wellbore, the operations comprising: 
 
   determining, based at least in part on information received from one or more of a data log and the on-board sensor suite, that the downhole perforation drone has reached the target area, wherein determining that the downhole perforation drone has reached the target area based on information detected by the GPS aided by the CCL and the gamma ray tool;   causing the perforation charge circuit to ignite the perforation charges after the downhole perforation drone reaches the target area; and
 a second portion comprising a plurality of perforation charges, the plurality of perforation charges to ignite upon receiving an instruction from the perforation charge circuit. 
   
     
     
         2 . The downhole perforation drone of  claim 1 , the operations further comprising:
 determining, based at least in part on information from one or more of the data log and the on-board sensor suite, that the downhole perforation drone has reached a target depth that corresponds to a depth of a target perforation area of the wellbore, and   causing the perforation charge circuit to ignite the perforation charges after the microcontroller has determined that the downhole perforation drone has reached the target depth.   
     
     
         3 . The downhole perforation drone of  claim 2 , further comprising extendable support structures, the operations further comprising:
 extending the support structures after determining that the downhole perforation drone has reached the target depth to support the downhole perforation drone in place in the wellbore; and   automatically cause the perforation charge circuit to ignite the perforation charges upon the determination that the downhole perforation drone has reached the depth of the target perforation area and after extending the support structures.   
     
     
         4 . The downhole perforation drone of  claim 2 , the microcontroller to:
 send, by the communications system, a wireless signal to the surface indicating that the depth of the downhole perforation drone corresponds to the depth of a target perforation area of the wellbore;   receive, by the communications system, a wireless signal an instruction to ignite the charges; and   cause the perforation charge circuit to ignite the perforation charges based on receiving the instruction.   
     
     
         5 - 6 . (canceled) 
     
     
         7 . The downhole perforation drone of the  claim 1 , wherein the one or more sensors comprise one or more of a gyroscope, a gamma ray detector, a pressure sensor, and a temperature sensors. 
     
     
         8 . The downhole perforation drone of  claim 1 , further comprising a hook loop rigidly affixed to a distal end of the body. 
     
     
         9 . The downhole perforation drone of  claim 1 , wherein the body comprises poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). 
     
     
         10 . The downhole perforation drone of  claim 1 , wherein the body comprises an aluminum alloy. 
     
     
         11 . A method of perforating a wellbore comprising:
 traversing a wellbore by a downhole perforation drone, the downhole perforation drone comprising a sensor suite comprising a global positioning system, a gamma ray tool, and a casing-collar locator, perforation charge circuitry, and a plurality of perforation charges;   determining, by the sensor suite, that the downhole perforation drone has reached a target position in the wellbore, the one or more sensors comprising;   extending a plurality of support structures to secure the downhole perforation drone in place in the wellbore;   igniting, by the perforation charge circuitry, the plurality of perforation charges;   retracting the plurality of support structures; and   causing the downhole perforation drone to reside at a rat hole in the wellbore.   
     
     
         12 . The method of  claim 11 , further comprising determining that the wellbore was perforated by comparing a pressure at depth with a surface pressure. 
     
     
         13 . The method of  claim 11 , further comprising:
 sending a wireless communications signal from the downhole perforation drone to a surface location of the wellbore indicating that the downhole perforation drone has reached the target position in the wellbore;   receiving a wireless communications signal from the surface location instructing the downhole perforation drone to ignite the plurality perforation charges; and   causing, by the perforation charge circuitry, the plurality of perforation charges to ignite.   
     
     
         14 . The method of  claim 11 , further comprising automatically igniting the plurality of perforation charges based on the determination that the downhole perforation drone has reached the target position in the wellbore. 
     
     
         15 . The method of  claim 11 , wherein determining, by the one or more sensors, that the downhole perforation drone has reached a target position in the wellbore comprises comparing sensor information from the one or more sensors against reference values stored in memory.