Additive manufactured strain gauge on component surfaces for predictive failure monitoring

Abstract

An additively manufactured strain gauge resides on the surface of a component to monitor component fatigue. The strain gauge is additively manufactured, and applied to the curvature of the component surface through either a flexible substrate or through direct printing.

1 . An assembly comprising:
 a component having a surface;   a strain gauge additively manufactured thereon, the strain gauge comprising:
 an additively manufactured portion comprising:
 a conductive ink defining a sensing portion and one or more terminals; and 
 an encapsulating material; and 
 
 one or more flex leads connected to the one or more terminals; and 
   a controller electrically connected to the additively manufactured portion through the one or more flex leads.   
     
     
         2 . The assembly of  claim 1 , wherein the component is selected from the group consisting of a rotor blade, a floor panel, a wing leading edge, a horizontal stabilizer, a vertical stabilizer, and a heated inlet. 
     
     
         3 . The assembly of  claim 1 , wherein the conductive ink selected from the group consisting of carbon loaded, nano-carbon load, and nano-silver loaded inks. 
     
     
         4 . The assembly of  claim 1 , wherein the additively manufactured portion comprises a plurality of lines, each of the plurality of lines having a thickness between 20 and 300 microns. 
     
     
         5 . The assembly of  claim 4 , wherein each of the plurality of lines has a thickness between 50 and 100 microns. 
     
     
         6 . The assembly of  claim 1 , wherein the additively manufactured portion has a resistance of between 0.01 and 20 ohms per square per MIL. 
     
     
         7 . The assembly of  claim 6 , wherein the additively manufactured portion has a resistance of between 1 and 15 ohms per square per MIL. 
     
     
         8 . The assembly of  claim 1 , wherein the additively manufactured strain gauge is printed directly on the surface of the component. 
     
     
         9 . The assembly of  claim 1 , wherein the additively manufactured strain gauge is printed on a flexible substrate that is attached to the surface of the component. 
     
     
         10 . The assembly of  claim 1 , wherein the additively manufactured strain gauge is printed on a dielectric layer residing on the surface of the component. 
     
     
         11 . A system for monitoring fatigue of a component comprising:
 an additively manufactured strain gauge on a first surface of a component;   a controller for reading and analyzing data produced by the additively manufactured strain gauge;   an electrical connection between the additively manufactured strain gauge and the controller; and   a predictive program on the controller for predicting when the component will fail based on data from the additively manufactured strain gauge.   
     
     
         12 . A method of making a strain gauge on a component comprising:
 additively manufacturing a gauge onto a first surface;   applying the gauge onto the component; and   electrically connecting the gauge to an external controller.   
     
     
         13 . The method of  claim 12 , wherein the first surface comprises a surface on the component. 
     
     
         14 . The method of  claim 12 , wherein the first surface comprises a flexible substrate, and wherein applying the gauge onto the component comprises adhering the flexible substrate to the component. 
     
     
         15 . The method of  claim 12 , wherein additively manufacturing the gauge comprises printing the gauge during manufacture of the component. 
     
     
         16 . The method of  claim 12 , wherein electrically connecting the gauge comprises attaching one or more leads between the gauge and the external controller. 
     
     
         17 . The method of  claim 12 , further comprising encapsulating the gauge. 
     
     
         18 . The method of  claim 17 , wherein additively manufacturing the gauge comprises screen printing, ink-jet printing, or aerosol printing the gauge. 
     
     
         19 . The method of  claim 17 , wherein additively manufacturing the gauge comprises printing with a carbon loaded or silver loaded ink.