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:
Aug. 10, 1999
Filed:
Feb. 06, 1997
Chadwick J Cox, Chattanooga, TN (US);
Carl E Lewis, Chattanooga, TN (US);
Accurate Automation Corporation, Chattanooga, TN (US);
Abstract
The apparatus of this invention includes a pilot-induced oscillation (PIO) detector, a PIO compensator and a pilot input modifier. The PIO detector is coupled to receive aircraft state signal including the aircraft's pitch, roll and yaw attitudes. The PIO detector is also coupled to receive pilot control signal generated by the aircraft's pilot by manipulation of flight control instruments. Preferably, the PIO detector includes a feature calculator and a discriminator. Based on the aircraft state signal and the pilot control signal, the feature calculator generates at least one feature signal indicative of whether a PIO or non-PIO condition exists in the aircraft. The feature calculator supplies the feature signal to the discriminator, that uses the feature signal to determine whether or not a PIO condition exists. The discriminator preferably uses a discrimination function determined by a neural network trained to discriminate PIO and non-PIO conditions, to generate the PIO indicator signal based on the feature signal(s). The discriminator generates the PIO indicator signal that indicates the likelihood of the existence of a PIO condition in the aircraft. The PIO indicator signal can be coupled to an audio and/or visual alarm to warn the pilot that the pilot's control actions are driving the PIO condition. The PIO compensator is coupled to receive the PIO indicator signal, and generates the compensation signal using the PIO indicator signal. The PIO compensator is coupled to output the PIO compensation signal to a pilot input modifier. In addition to the compensation signal, the pilot input modifier receives and modifies the pilot control signal, based on the compensation signal. The pilot input modifier can accomplish appropriate modification through gain attenuation or phase shift of the pilot control signal. The modified pilot control signal is used to control the aircraft's flight control actuators to eliminate the PIO condition. Accordingly, the invented apparatus prevents aircraft damage or pilot injury or death, that could otherwise result from a PIO condition. The invention also includes a related method.