Videometric research on deformation measurement of large-scale wind turbine blades

Utilization of wind energy is a promising way to generate power, and wind turbine blades play a key role in collecting the wind energy effectively. This paper attempts to measure the deformation parameter of wind turbine blades in mechanics experiments using a videometric method. In view that the blades experience small buckling deformation and large integral deformation simultaneously, we proposed a parallel network measurement (PNM) method including the key techniques such as camera network construction, camera calibration, distortion correction, the semi-automatic high-precision extraction of targets, coordinate systems unification, and bundle adjustment, etc. The relatively convenient construction method of the measuring system can provide an abundant measuring content, a wide measuring range and post processing. The experimental results show that the accuracy of the integral deformation measurement is higher than 0.5mm and that of the buckling deformation measurement higher than 0.1 mm. (C) 2011 The Chinese Society of Theoretical and Applied Mechanics.