| Significant research has been applied to developing and using stereophotogrammetry techniques for the measurement of static, quasi-static and non-rotating systems. Further development of this optical measurement technique has extended its capabilities to collect dynamic operating data on both small and large rotating structures including wind turbines and helicopter rotors and it has been found to be quite advantageous over conventional, accelerometer-data acquisition systems (DAQ) for several reasons. First, this is a non-contacting technique that doesn't require the use of mounted transducers minimizing the potential for mass loading error or changes to the aerodynamics of the structure and eliminates the need for physical wiring. Second, dynamic displacement data can be collected on many hundreds of points on a structure surface outnumbering the channel counts of typical data acquisition systems. Third, this measurement technique is capable of measuring extremely low frequency dynamics often below the frequency range of standard accelerometers. The work presented in this thesis extends prior research applying stereophotogrammetry to the measurement of rotating system dynamics with detailed rigid body correction studies and the measurement of the dynamics of a large, turbine-like structure and a full-scale Robinson R44 Raven helicopter to obtain operating deflection shapes. The optical measurement techniques presented in this work are shown to be viable approaches to measure and analyze the dynamics of large, rotating systems. |
