Research Of The Key Technology And System Development Based On Binocular Stereo Vision In Wind Tunnel Experiment

The main task of wind tunnel experiment is simulating the situation when air flow through the model and providing accurate data, because the accurate measurement of model's attitude and key points' trail can help us better understand the aircraft flight attitude and all parts that might change. So whether the data is accurate directly related to the choice of aircraft design plan and the success of development. How to obtain the high accurate data has been the problem to all wind tunnel workers, aircraft designers and aerodynamics researchers.According to the requirement of tracking model's key points and measuring model's attitude, the key technology that vision measurement need in wind tunnel experiment has been researched. The system based on binocular stereo vision principle is developed by using VC++ and MATLAB software development platform combined with the hardware device. The precision examine equipment is used to check the system's precision and the results are acceptable. Then the system is applied into wind tunnel experiment, the structure and installation plan of the system are well designed according to the wind tunnel's situation and experiment conditions. The experiment data are well obtained and displayed by the system.Here are the main work this article include:1) The Study of the measurement system's three coordinate system and the conversion among them, the principle of pinhole imaging, the distortion of camera lens and the measurement principle of the system.2) The Study of the design and recognition of marked targets, the technology of center extraction and encoding marked targets.3) The Study of the calibration of internal parameters, the calibration of external parameters and the adjustment of beam method.4) The measurement system's hardware structure, software function and the design of shooting process are completed according to the wind tunnel's environment and the data that experiment need.5) The precision examine experiment is designed and finished. When the measurement space is 2000 mm *1800mm * 1500 mm, the displacement accuracy is better than 0.5mm, and the angle accuracy is better than 0.05, which is good for the wind tunnel experiment.6) According to the actual situation of the wind tunnel field, the experiment is designed and completed in the wind tunnel and the measure effect is good.