MBL meets OPTIMESS 2019 lecture:
"Optical measurement techniques"
Camera based optical measurement systems such as Digital Image Correlation (DIC) are increasingly used in industrial environments to validate model simulations. Although DIC is a well-established technique for measuring displacement and strain fields, the estimation of its measurement uncertainty in an industrial environment is still being discussed. The calibration uncertainty for the DIC system represents the minimum achievable measurement uncertainty in a validation experiment, and a methodology for estimating the measurement uncertainty in a validation experiment will be discussed.
A recent guideline published by CEN details the comparison of simulation data with data from full-field measurements for the purpose of validating the numerical model. The guideline recommends the use of full-field data, e.g. obtained from calibrated DIC systems, and the application of image decomposition. While an inter-laboratory study demonstrated its usefulness in a laboratory environment on different representative test objects, the methodology is now being deployed in an advanced structural test in an industrial environment.
We will present a step-by-step procedure to the validation process in an industrial environment based on a novel flowchart with a focus on the data generation from experiment and simulation. We will present a novel flowchart for validation and relate it to the recommendations of the ASME V&V and CEN guidelines. Difficulties in the practical applicability, such as complex geometry, or lack of numerical or experimental data points (e.g. due to optical inaccessibility, or element erosion in damaged areas of the FE models) and their mitigation will be addressed.