LiDAR-based displacement measurement and data decoupling method for biaxial fatigue testing of wind turbine blades

To improve the efficiency of wind turbine blade fatigue testing, a displacement measurement method for wind turbine blades based on LiDAR is proposed, which is suitable for biaxial fatigue testing of wind turbine blades. By utilizing the geometric characteristics of retroreflective targets captured by the LiDAR, the position of target points is determined, and the displacement of these points during testing is calculated. The feasibility of this method is verified through static and dynamic experiments, with experimental results showing that the distance measurement error is controlled within 5%. This method requires low point cloud density from the LiDAR and offers advantages such as minimal environmental impact and non-contact measurement. Additionally, an optimization-based vibration parameter calculation method is proposed, which can accurately compute vibration parameters such as frequency and phase. By decoupling the data using vibration parameters, this approach provides additional data support for the fatigue testing of wind turbine blades.