Here, aiming at limitations of vision-based structural displacement measurement method, such as, insufficient resolution of camera or difficulty in selecting location of measurement base station, a structural dynamic displacement measurement method combining machine vision and unmanned aerial vehicle (UAV) was proposed. Taking laser spot projected by static laser lamp on structure surface as a reference, an algorithm was designed to automatically detect target measurement point and laser spot position, calculate and update scale factor frame by frame, estimate and eliminate motion of UAV itself, and then calculate absolute displacement of target measurement point. In order to verify the accuracy of the proposed method, a small frame model test was designed, and then this method was applied in large-scale earthquake simulation shaking table tests. The results showed that displacement responses obtained using the proposed method agree well with the reference data measured using laser displacement meter and accelerometer; the proposed method can better be applied in structural dynamic displacement measurement and modal parametric identification.
Key words
displacement measurement /
modal parametric identification /
unmanned aerial vehicle (UAV) /
machine vision /
camera motion correction
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