7.4 - Optical Rotor-Blade Deformation Measurements using a Rotating Camera

ettc2018 - European Test and Telemetry Conference
2018-06-26 - 2018-06-28
Nürnberg, Germany
7. AIM 2018
F. Boden, B. Stasicki - German Aerospace Center, Institute of Aerodynamics and Flow Technology, Göttingen (Germany), K. Ludwikowski - HARDsoft Microprocessor Systems, Krakow (Poland)
147 - 154


For the design of rotors for helicopters or wind turbines, the knowledge of movements and deformations of the rotor blades is important. Measuring these parameters in the rotating system is difficult, because the number of sensors is limited due to their impact on the aerodynamics and the modification of the structure. Strain gauge measurements furthermore can be affected e.g. by the sensor location or temperature effects. To avoid those problems and in addition enable direct shape measurements, optical methods have been applied to rotor deformation measurements in the past. These attempts have been done out of the rotating frame observing either only small rotors or the blade passing the field of view. DLR and Hardsoft developed a rotating 3D imaging system for helicopter rotors and performed tests on the whirltower of Airbus Helicopters in Donauwörth (GER).
The system is mounted on the hub and co-rotates with the rotor. It is able to record images of the whole blade at each azimuth angle. Those images later are processed with an Image Pattern Correlation Technique (IPCT) software tool and deliver the 3D surface shape and location of the observed blade. The paper briefly describes the rotating camera system, the non-intrusive deformation measurement method IPCT and the measuring setup, as well as the obtained data and a discussion of the measurement results.