The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 19, 2002
Filed:
Jul. 12, 2001
Ralph Pringle, Jr., Albuquerque, NM (US);
Felix E. Morgan, Albuquerque, NM (US);
The B. F. Goodrich Co., Charlotte, NC (US);
Abstract
A method for determining a resonant frequency of a mechanical device having a first mass and at least one second mass mechanically coupled to the first mass comprises the steps of: providing a control signal to a voltage-controlled oscillator (VCO) to control the frequency of an output thereof; translating a phase shifted output of the VCO into an oscillatory force which is applied to one of the first and second masses to cause the mechanical device to respond; measuring the response of the mechanical device and generating a response signal representative thereof in frequency and amplitude; generating an error signal proportional to the phase difference between a signal representative of the output of the VCO and the measured response signal; adjusting the control signal to cause the oscillatory force applied to the one mass to sweep within a calculated frequency range rendering the amplitude of the response signal to approach and exceed a calculated threshold value; and when the calculated threshold is exceeded by the amplitude of the response signal, finely adjusting the control signal to the VCO until the value of the measured error signal is equal substantially to a calculated final error value, whereupon the frequency of the response signal is the resonant frequency of the mechanical device.