Patents Assigned to The Modal Shop
  • Patent number: 8577641
    Abstract: An improved method for calibration of dynamic motion sensors. In one aspect, the method comprises sending a low frequency driving signal to an exciter to generate a harmonic movement in a shaker table, using an optical position sensor to produce an output representative of position, computing the acceleration of the shaker table and a dynamic motion sensor under test (SUT), and comparing the output of the SUT with the instantaneous acceleration of the shaker table at different frequencies sufficient to define the performance characteristics of the SUT within a selected frequency range, among other things. In another aspect, the method comprises calibration of a dynamic motion SUT by simultaneous direct measurement of position and time. In another aspect, the optical position sensor has an electrical output representative of position for attaining a desired degree of positional accuracy.
    Type: Grant
    Filed: September 3, 2012
    Date of Patent: November 5, 2013
    Assignee: The Modal Shop
    Inventors: Robert D Sill, Mark I Schiefer, Joshua B Moses
  • Publication number: 20130013241
    Abstract: An improved method for calibration of dynamic motion sensors. In one aspect, the method comprises sending a low frequency driving signal to an exciter to generate a harmonic movement in a shaker table, using an optical position sensor to produce an output representative of position, computing the acceleration of the shaker table and a dynamic motion sensor under test (SUT), and comparing the output of the SUT with the instantaneous acceleration of the shaker table at different frequencies sufficient to define the performance characteristics of the SUT within a selected frequency range, among other things. In another aspect, the method comprises calibration of a dynamic motion SUT by simultaneous direct measurement of position and time. In another aspect, the optical position sensor has an electrical output representative of position for attaining a desired degree of positional accuracy.
    Type: Application
    Filed: September 3, 2012
    Publication date: January 10, 2013
    Applicant: THE MODAL SHOP INC.
    Inventors: Robert D. Sill, Mark I. Schiefer, Joshua B. Moses
  • Patent number: 8280666
    Abstract: The invention disclosed includes a method for determining the magnitude and phase calibration of dynamic motion sensors (SUTs), such as accelerometers, velocimeters, and dynamically responding displacement transducers at low vibration frequencies, using an optical encoder as the reference. To calibrate the sensitivity, the dynamic motion sensor is mounted to a shaker mechanism which imparts harmonic linear motion in the axis of the sensitivity of the sensor. In the case of an accelerometer, the mechanism commonly includes another accelerometer as a reference sensor. However, the output of conventional reference accelerometers becomes inadequate at low frequencies. The subject of this patent is an optical encoder to measure the displacement, at frequencies at which the optical measurement is more accurate than that of an accelerometer or other dynamic motion sensor.
    Type: Grant
    Filed: November 20, 2008
    Date of Patent: October 2, 2012
    Assignee: The Modal Shop, Inc.
    Inventors: Robert D. Sill, Mark I. Schiefer, Joshua B. Moses
  • Publication number: 20090182521
    Abstract: The invention disclosed includes a method for determining the magnitude and phase calibration of dynamic motion sensors (SUTs), such as accelerometers, velocimeters, and dynamically responding displacement transducers at low vibration frequencies, using an optical encoder as the reference. To calibrate the sensitivity, the dynamic motion sensor is mounted to a shaker mechanism which imparts harmonic linear motion in the axis of the sensitivity of the sensor. In the case of an accelerometer, the mechanism commonly includes another accelerometer as a reference sensor. However, the output of conventional reference accelerometers becomes inadequate at low frequencies. The subject of this patent is an optical encoder to measure the displacement, at frequencies at which the optical measurement is more accurate than that of an accelerometer or other dynamic motion sensor.
    Type: Application
    Filed: November 20, 2008
    Publication date: July 16, 2009
    Applicant: The Modal Shop, Inc.
    Inventors: Robert D. Sill, Mark I. Schiefer, Joshua B. Moses