A Method for Helicopter Blade Mass Unbalance Detection Based on Fiber Bragg Grating Vibration Sensing System

Abstract

The invention provides a method for detecting the mass imbalance of a helicopter blade based on a fiber grating vibration sensing system. The fiber grating sensor is arranged on the surface of the blade (1) and the surface (2) of the blade base of the helicopter. The ring and the optical cable are connected to the demodulator and the host computer at the rear. When the blade rotates, the strain on the surface of the blade and the vibration of the base of the blade are sensed (3) and the data is collected (4). When the data processing system at the rear passes through Domain analysis (5) and frequency domain analysis (6), extract data features, and compare with the data of normal blades, so as to judge whether the quality of helicopter blades is unbalanced and the degree of unbalance (7). The invention overcomes the time-consuming, labor-intensive, low-accuracy, and certain dangers of the artificial paper tube-type benchmarking method, and the disadvantages of the stroboscope target method relying on human eyes being unobjective and taking a long time to calibrate, and can objectively measure the mass imbalance of helicopter blades. , accurate detection and quantitative analysis.

Description

technical field [0001] The invention belongs to the field of structural health monitoring, in particular to a method for detecting the mass imbalance of a helicopter blade based on a fiber grating vibration sensing system. Background technique [0002] Helicopter rotor, as the core component that provides lift and control force for helicopter flight, is directly related to the safety of helicopter and the pros and cons of other important performances. The cone produced by the high-speed rotation of the helicopter rotor is a comprehensive reflection of the technical state of the helicopter rotor system, including changes in the quality of the blades, blade installation and fixing, etc., which are reflected in the changes in the cones of the rotor. Among them, the mass imbalance of the blades will cause the vibration of the aircraft fuselage, which will affect the flight safety. problem is detected. [0003] There are two traditional methods for measuring blade mass imbalanc...

AI Technical Summary

Problems solved by technology

Compared with the artificial paper tube target method, this method has made some progress, but it still has disadvantages: 1. It cannot record data, relies on human judgment, and is not objective enough and cannot perform quantitative analysis; 2. It takes a long time to lock the target for the first time, and it may Helicopter body structure poses a hazard

At present, there are no examples and patents of applying fiber grating sensors to the unbalance detection of helicopter blades, but the advantages of fiber grating sensors make them have good application prospects, and the invention content of this patent is also rich. Practical

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