Research status and application of videogrammetric measurement techniques for wind tunnel testing.

Videogrammetric measurement (VM) becomes a focus technique at home and abroad because of its no special requirements on the test model and its non-contact way for wind tunnel testing. VM techniques and their applications for wind tunnel testing in highly developed institutes abroad are firstly introduced in detail, and some problems about the VM used in high speed intermittent wind tunnels at home are analyzed. Dynamic calibration for multi-cameras and sequential images matching technique for the mark points based on motion evaluation are developed in CARDC in order to achieve the high precision pose measurement in noise (about 130dB)/vibration environment. The potential application prospects of VM have been demonstrated by several preliminary testing cases in a 2 meter supersonic tunnel tests and a 2.4 meter transonic tunnel, including angles of attack and sideslip measurement of test model, deformation of full size embedded door and a static aero-elastic test model, which shows the precision of VM is high. On the other hand, VM can be used to determine the optical path difference (OPD) by measuring the deviation displacement field induced by the beams from center of camera to the background points crossing the flow field, provides a new way to research and measure aero-optic effects and flow display at the surface of the testing model, which is simple and needs no expensive coherent sources. [ABSTRACT FROM AUTHOR]