The Wire-Driven Parallel Robot (WDPR) provides a new supporting method for wind tunnel tests, and it can be used for complex and dynamic multi/six-DoF motion in wind tunnel tests. Aiming at the large-scale dynamic motion of aircraft model suspended by WDPR, a position and attitude dynamic measurement method for aircraft model based on binocular vision technique is developed. First, a type of encoded round marker is designed to be affixed on the model surface. Following the reconstruction of markers' 3D coordinates, the interference of cables to markers imaging is eliminated by image processing. Second, the initial value of relative pose is estimated by the absolute orientation algorithm, and a theoretical error analysis is given. Then the optimal result is achieved through building an unconstrained least squares optimization problem in Lie Algebra based on re-projection error, which is solved by the L-M optimization algorithm. Finally, the static and dynamic test validations and three typical dynamic single/multi-DoF motions for aircraft model such as heave/pitch oscillation are conducted. The results indicate that the precision of static angle and displacement measurement is better than 0.02°/0.02 mm respectively, and that of dynamic angle measurement can achieve the 0.1° order, and the absolute error of the dynamic displacement is 0.4 mm. The research conducted shows that the proposed binocular vision measurement system is effective and feasible, and it could provide sufficient support for the practical application in the follow-up wind tunnel tests.
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