Patents by Inventor Douglas R. Earnest

Douglas R. Earnest has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20240280424
    Abstract: A method for detecting residual stress induced by cold expansion (Cx) (Cx stress) at a hole in a structure. Two transducer pairs transmit and receive ultrasonic waves into the structure in a pitch-catch configuration along two first paths parallel to a tangent of the hole. The two paths are at different distances from the hole. Both transducer pairs are arranged such that their incident angle into the structure provides longitudinal critically refracted (LCR) waves within the structure. Time-of-flight (ToF) measurements of the LCR waves along the first path and the second path are the basis of acoustoelasticity calculations that determine if Cx stress is present at the hole.
    Type: Application
    Filed: February 19, 2024
    Publication date: August 22, 2024
    Inventors: Xin Chen, Adam C. Cobb, Douglas R. Earnest, Clint J. Thwing, Nikolay Akimov
  • Publication number: 20230393098
    Abstract: A method of in situ measurement of an acoustoelastic constant (L) of a railway rail, using an ultrasonic wedge sensor to measure a stress-free (unloaded) time-of-flight (t0) in the vertical direction of the rail. Next, a vertical load of known load value is applied to the rail. While the vertical load is applied, the ultrasonic wedge sensor is used to measure a stressed time-of-flight value. The difference between the stress-free and the stressed time-of-flight is calculated to obtain a time-of-flight difference value (?t). Based on the load value, the stress-free time-of-flight value, and the time-of-flight difference value, the acoustoelastic constant, L, may be calculated. The wedge sensor may be further used to measure the (stressed) horizontal time of flight, and a time-of-flight difference value in the horizontal direction may be used to measure longitudinal stress.
    Type: Application
    Filed: May 31, 2023
    Publication date: December 7, 2023
    Inventors: Xin Chen, Adam C. Cobb, Douglas R. Earnest, Keith A. Bartels
  • Patent number: 10739314
    Abstract: A guided wave probe for use in guided wave testing of plate structures. The probe comprises a cup having a flat or nearly flat bottom, and a guided wave sensor, such as a magnetostrictive sensor, placed in the bottom of the cup. The sensor and/or cup are coupled to the plate structure, such that ultrasonic energy from the sensor is transmitted to the cup and the plate surface. The sensor is incrementally rotated in the cup, and sensor data is acquired at each incremental position.
    Type: Grant
    Filed: December 18, 2017
    Date of Patent: August 11, 2020
    Assignee: Southwest Research Institute
    Inventors: Sergey A. Vinogradov, Adam C. Cobb, Jonathan D. Bartlett, Greg A. Bustamante, Douglas R. Earnest, Clinton J. Thwing
  • Publication number: 20190187104
    Abstract: A guided wave probe for use in guided wave testing of plate structures. The probe comprises a cup having a flat or nearly flat bottom, and a guided wave sensor, such as a magnetostrictive sensor, placed in the bottom of the cup. The sensor and/or cup are coupled to the plate structure, such that ultrasonic energy from the sensor is transmitted to the cup and the plate surface. The sensor is incrementally rotated in the cup, and sensor data is acquired at each incremental position.
    Type: Application
    Filed: December 18, 2017
    Publication date: June 20, 2019
    Inventors: Sergey A. VINOGRADOV, Adam C. COBB, Jonathan D. BARTLETT, Greg A. BUSTAMANTE, Douglas R. Earnest, Clinton J. THWING