Structural modal parameter identification system based on binocular stereo vision

Abstract

The invention discloses a structural modal parameter identification system based on binocular stereo vision. The method of the system comprises the following steps of building a binocular stereo vision system, calibrating two camera units, and acquiring internal and external parameters of the two camera units to carry out three-dimensional correction; establishing easily identifiable key points of a detected structure surface; loading impact force to enable the detected structure to move freely, obtaining a synchronic image sequence file, identifying the three-dimensional coordinates of all key points to each frame of image orderly, and obtaining the three-dimensional movement data of all key points in the whole test time finally; through the three-dimensional movement data of all key points, carrying out modal identification by using a characteristic system realization algorithm, obtaining the modal parameters of the detected structure, and outputting a result. Compared with the traditional technology, the structural modal parameter identification system can measure the modal parameters of the detected structure in a non-contact way or in a way that less impact is applied to the detected structure, and the system has the advantages of low cost, fast speed and high precision and is especially suitable for the modal parameter measurement of large lightweight structure with inconvenient layout of sensors.

Description

technical field [0001] The invention belongs to the intersecting field of image vision field and dynamic modal parameter identification, and relates to establishment of a binocular stereo vision system, identification of key points, calculation of three-dimensional motion data, and identification algorithm of structural modal parameters. Background technique [0002] Structural modal parameter identification is an important means for the design and analysis of structural dynamic performance. Online modal parameter identification has important application value for active control of structural vibration, damage identification, fault prediction and diagnosis, and structural health monitoring. The development of modern engineering structures tends to be lightweight and large-scale, and some structures even work in extreme environments, such as high temperature and outer space. The traditional vibration test based on contact measurement is no longer suitable for the identificati...

AI Technical Summary

Problems solved by technology

The traditional vibration test based on contact measurement is no longer suitable for the identification of modal parameters of some modern engineering structures due to problems such as affecting the modal parameters of lightweight structures, being difficult to measure in extreme environments, and requiring large-scale layout of data lines. Turbine blades working at high temperature and high speed, large-area solar wings on space stations

Images