Non-contact vibration detecting method of tower crane structure

Abstract

The invention relates to a non-contact vibration detecting method of a tower crane structure and belongs to the technical field of detecting. The method is non-contact measurement. A multipoint and on-line test can be achieved by arranging a plurality of cameras without arranging a sensor on a detected object. The non-contact vibration detecting method of the tower crane structure has no load effect and is easy to implement. Image information is directly digitalized to form a full-automation and full-digitalization vibration measurement disposing and recording system. Amount of information is larger than that of a traditional method. Regions of interest (ROI)technology is used in the method to reduce an image tracking area and calculated amount. Speeded-up robust features (SURF) method is used to accelerate extraction rate of feature points. The PauTa criterion is used to reject'outlier' and improve accuracy of the SURF method. Reliability of a crane safety monitoring system in prior art is improved.

Description

technical field [0001] The invention relates to a non-contact vibration detection method for a tower crane structure, belonging to the technical field of detection. Background technique [0002] The most commonly used method for vibration detection of metal structures of cranes is to measure the strain and stress of the tower crane structure by electrical measurement. The strain electric measurement method is an experimental stress analysis method that uses the resistance strain gauge to measure the strain of the component, and then determines the stress state of the component according to the relationship between stress and strain. Its measurement system usually consists of four parts: strain gauges, strain gauges, recorders, and computing and analysis equipment. This experimental method requires multiple strain gauges to be pasted on the crane. Since the crane is moving and has a huge external dimension, it is impossible to completely use wires to gather the signals of th...

AI Technical Summary

Problems solved by technology

[0024] In the existing vibration detection technology of cranes, strain gauges and acceleration sensors are mostly used as signal acquisition units; a large number of wires must be laid to conduct signals or wireless signals are used; of course, wireless transmission methods are also used to transmit signals. The installation and use of the device are relatively complicated; it is also prone to failure; due to the special lifting conditions, troubleshooting is still very troublesome; the price of this structure is also very expensive; the number of measurement points is also very limited; and it affects the production of the crane

Therefore, the use of this technology is very limited

[0025] In addition, using the finite element method to simulate the crane has certain significance for theoretical research. Even if the simplification and establishment of the model can be consistent with the actual crane, this method is powerless for the measurement of the vibration of the crane used in reality.

Images