Vibration correction algorithm for surface stress sensitive film technology
The unstable vibration of the surface stress sensitive film sensing system in the wind tunnel brings large er-rors to the measurement results.A self-calibration method is proposed to perform vibration correction on the sensing im-ages to eliminate the effect of unstable platform vibration and reduce the measurement errors.The initial displacement containing vibration and effective information is firstly obtained by cross-correlating the original sensing images,then the reference zone mask is obtained by Otsu thresholding method and morphology,and finally the whole vibration plane is re-stored and vibration corrected using the principle of perspective transformation and the least-squares method.The method involves the sub-zones of the sensitive membrane sensing image as feature points in the calculation,realizes the self-cali-bration correction of vibration,and enables the sensing system to perform high-precision measurement even on unstable platforms.The validity and practicability of the method are verified by high-speed train experiments,which show that the method has higher accuracy and better robustness than other traditional methods,produces good spatio-temporal resolu-tion images,and reduces the vibration average error by 98％in an incoming flow of 50m/s.
NETL
NSTL
万方数据
