Blade-mounted sensor apparatus, systems, and methods

Abstract

In some embodiments, an apparatus and a system may include a tubular member; at least two interchangeable blades attached to the tubular member, the blades extendible radially outward to an extended position and retractable radially inward to a retracted position, wherein an outer surface of the blades is disposed at or below an outer surface of the tubular member when the blades are in the retracted position; and a plurality of sensors attached to the blades, the sensors to engage a circumferential portion of a borehole wall along the outer surface of the blades in an azimuthal direction when the blades are disposed downhole in the extended position, and to refrain from engaging the borehole wall when the blades are disposed downhole in the retracted position. Additional apparatus and systems, as well as methods, are disclosed.

What is claimed is: 
     
         1 . An apparatus, comprising:
 a tubular member;   at least two interchangeable blades attached to the tubular member, the blades extendible radially outward to an extended position and retractable radially inward to a retracted position, wherein an outer surface of the blades is disposed at or below an outer surface of the tubular member when the blades are in the retracted position; and   a plurality of sensors attached to the blades, the sensors to engage a circumferential portion of a borehole wall along the outer surface of the blades in an azimuthal direction when the blades are disposed downhole in the extended position, and to refrain from engaging the borehole wall when the blades are disposed downhole in the retracted position.   
     
     
         2 . The apparatus of  claim 1 , wherein the tubular member comprises one of a drilling collar or a crossover sub. 
     
     
         3 . The apparatus of  claim 1 , wherein the at least two interchangeable blades comprise identical blades. 
     
     
         4 . The apparatus of  claim 1 , wherein the at least two interchangeable blades comprise three or four interchangeable blades, each of the blades occupying a substantially similar portion of a circumference of the tubular member when the blades are in the retracted position. 
     
     
         5 . The apparatus of  claim 1 , wherein each of the blades overlap at least one other one of the blades along the circumference of the tubular member when the blades are in the retracted position. 
     
     
         6 . The apparatus of  claim 1 , further comprising:
 gears, electromagnetic, piezoelectric, shape memory alloy, or hydraulic actuators to couple the tubular member to the blades.   
     
     
         7 . The apparatus of  claim 1 , wherein the plurality of sensors comprise at least two different sensor types arranged on one of the blades. 
     
     
         8 . The apparatus of  claim 1 , wherein each of the blades includes end pieces that engage end pieces of other blades in a mirrored fashion when the blades are in the retracted position. 
     
     
         9 . The apparatus of  claim 1 , wherein the outer surface of the blades substantially conforms to the outer surface of the tubular member, to form a substantially continuous outer surface, when the blades are in the retracted position. 
     
     
         10 . The apparatus of  claim 1 , wherein each of the blades is attached to the tubular member at a single point of rotation. 
     
     
         11 . The apparatus of  claim 10 , wherein the single point of rotation comprises an aperture in the blade extending in a longitudinal direction of the tubular member and located on an interlocking portion of the blade. 
     
     
         12 . The apparatus of  claim 1 , wherein the sensors comprise at least one transducer. 
     
     
         13 . The apparatus of  claim 1 , wherein each of the blades is formed in a crescent shape. 
     
     
         14 . The apparatus of  claim 1 , further comprising:
 multiple sets of the at least two interchangeable blades, each of the sets attached to the tubular member at a different longitudinal location.   
     
     
         15 . The apparatus of  claim 1 , wherein at least some of the plurality of sensors form a portion of the outer surface of the blades. 
     
     
         16 . A system, comprising:
 a controller; and   an apparatus operatively coupled to the controller, the apparatus comprising a tubular member attached to at least two interchangeable blades, the blades extendible radially outward responsive to receiving an extend command issued by the controller, to an extended position, and retractable radially inward responsive to receiving a retract command issued by the controller, to a retracted position, wherein an outer surface of the blades is disposed at or below an outer surface of the tubular member when the blades are in the retracted position; and   a plurality of sensors attached to the blades, the sensors to engage a circumferential portion of a borehole wall along the outer surface of the blades in an azimuthal direction when the blades are disposed downhole in the extended position, and to refrain from engaging the borehole wall when the blades are disposed downhole in the retracted position.   
     
     
         17 . The system of  claim 16 , wherein the tubular member comprises a portion of a drill string, and wherein the apparatus operates as a passive stabilizer to centralize the drill string when the blades are in the extended position. 
     
     
         18 . The system of  claim 16 , wherein the outer surface of the blades operate to complete the outer surface of the tubular member when the blades are in the retracted position. 
     
     
         19 . A method, comprising:
 lowering a tubular member into a borehole while at least two interchangeable blades attached to the tubular member are in a retracted position, the blades retractable radially inward from an extended position to the retracted position, wherein an outer surface of each of the blades is disposed at or below an outer surface of the tubular member when the blades are in the retracted position; and   extending the blades radially outward into the extended position to engage, by the outer surface of each one of the blades and a plurality of sensors attached to the blades in an azimuthal direction, a circumferential portion of a wall of the borehole.   
     
     
         20 . The method of  claim 19 , wherein extending the blades further comprises:
 rotating a geared mechanism or activating an electromagnetic, piezoelectric, shape memory alloy, or hydraulic actuator attached to the blades.   
     
     
         21 . The method of  claim 19 , further comprising:
 measuring a resistance force encountered by one or more of the blades; and   ceasing to extend the blades when a preselected amount of the resistance force is measured.   
     
     
         22 . The method of  claim 19 , further comprising:
 acquiring sensor data from the plurality of sensors, wherein at least two different sensor types are located on at least one of the blades.   
     
     
         23 . The method of  claim 19 , further comprising:
 retracting the blades radially inward into the retracted position;   drilling into a geological formation surrounding the borehole, to extend a length of the borehole, using a drill string that includes the tubular member; and   extending the blades radially outward into the extended position to stabilize the drill string within the borehole.