Self-powered sensors for detecting downhole parameters

A self-powered sensor array for sensing environmental parameters along a drillstring, the self-powered sensor arrays comprising:

• an outer collar having a plurality of moveable member retainers formed therein;
• a plurality of moveable members movably disposed in the plurality of moveable member retainers;
• an inner ring rotatably supported within the outer collar;
• a plurality of bearing elements retained on an outer surface of the inner ring, each bearing element positioned to displace the moveable members relative to the moveable member retainers in response to relative rotation between the inner ring and the outer collar;
• a plurality of shape memory material elements, each shape memory material element arranged in a respective moveable member retainer of a first fraction of the plurality of moveable member retainers;
• a plurality of distance sensors, each distance sensor disposed in the respective moveable member retainer and between the shape memory material element in the respective moveable member retainer and a respective moveable member movably disposed in the respective moveable member retainer, each distance sensor comprising a first sensing element and a second sensing element arranged in opposing relation, the first sensing element and the second sensing element separated by a gap that is responsive to a shape change of the respective shape memory material element and a displacement of the respective moveable member;
• and
• a plurality of power generation components, each power generation component arranged in relation to one of a second fraction of the plurality of moveable member retainers, the power generation component configured such that, in response to the relative rotation, the plurality of bearing elements displace a particular moveable member into a particular moveable member retainer, generating an electric charge.

A sensing system for sensing environmental parameters along a drillstring, the system comprising:

• a plurality of self-powered sensor arrays, each of the plurality of self-powered sensor arrays comprising:
• an outer collar having a plurality of moveable member retainers formed therein;
• a plurality of moveable members movably disposed in the plurality of moveable member retainers;
• an inner ring rotatably supported within the outer collar;
• a plurality of bearing elements retained on an outer surface of the inner ring, each bearing element positioned to displace the moveable members relative to the moveable member retainers in response to relative rotation between the inner ring and the outer collar;
• a plurality of shape memory material elements, each shape memory material element arranged in a respective moveable member retainer of a first fraction of the plurality of moveable member retainers;
• a plurality of distance sensors, each distance sensor disposed in the respective moveable member retainer and between the shape memory material element in the respective moveable member retainer and a respective moveable member movably disposed in the respective moveable member retainer, each distance sensor comprising a first sensing element and a second sensing element arranged in opposing relation, the first sensing element and the second sensing element separated by a gap that is responsive to a shape change of the respective shape memory material element and a displacement of the respective moveable member;
• a plurality of power generation components, each power generation component arranged in relation to one of a second fraction of the plurality of moveable member retainers, the power generation component configured such that, in response to the relative rotation, the plurality of bearing elements displace a particular moveable member into a particular moveable member retainer, generating an electric charge;
• and
• a communications device that transmits a signal that includes the gap of each distance sensor;
• and a receiver that receives the signal from the communications device within each of the plurality of sensor arrays.

A method for sensing of environmental parameters, the method comprising:

• disposing a plurality of self-powered sensor arrays on a drillstring, wherein each of the self-powered sensor arrays comprise an outer collar and an inner ring;
• disposing the drillstring with the plurality of self-powered sensor arrays in a wellbore;
• rotating the outer collar with respect to the inner ring of each of the plurality of self-powered sensor arrays;
• producing mechanical energy in each of the plurality of self-powered sensor arrays by bearing elements of each of the plurality of self-powered sensor arrays that physically interact with movable members of the self-powered sensor array as a result of the relative rotation between the outer collar and the inner ring of each of the plurality of self-powered sensor arrays;
• and
• generating an output reflecting gaps probed by distance sensors in each of the plurality of self-powered sensor arrays, where the gaps are responsive to shape changes of shape memory material elements resulting from environmental parameters within the wellbore and displacements of moveable members resulting from the relative rotation between the outer collar and the inner ring of each of the plurality of self-powered sensor arrays.