A Model Deformation Measurement Method and its Application on PSP Measurements

A method has been developed to correct the effects of model deformation on PSP images. This method is based upon grid tracking instead of marker tracking. The grid is deformed according to a deformation law which is designed by using mechanical and aerodynamic knowledge about the model behavior . The deformation law parameters are identified with the markers used for PSP registration. The identification algorithm is an extended version of the algorithm that identifies the position of the camera. The method has been applied on images obtained in a n Onera’s pressurized wind tunnel. The achieved accuracy is 0.1 pixel. The method has been extended so that it can handle several views and cameras. This enables to calibrate the internal camera parameters and to measure the model deformation, not only to correct its effect. One planed application is to measure the world coordinates of markers placed on the model by combining images taken around the model.

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