Patents by Inventor Michel J. Pettigrew

Michel J. Pettigrew 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).

  • Loose rock detector
    Patent number: 5024090
    Abstract: A loose rock detector comprises an impact tool for hitting the rock face, sensors for detecting acoustic, rock motion and/or impact force signals generated by movement of the impact tool against the face of the rock, a data processor responsive to the sensors for correlating the above signals in the time and/or frequency domain against predetermined relationships to detect loose rocks and to assess mass and degree of looseness of the rock, and a display unit for displaying the results of the correlation.
    Type: Grant
    Filed: September 15, 1989
    Date of Patent: June 18, 1991
    Assignee: HDRK Mining Research Limited
    Inventors: Michel J. Pettigrew, David B. Rhodes, Eric G. Lux, Victor A. Mason