Optical measurement of dynamic stress and strain

Understanding the origin of the stress and strain distribution is crucial to increasing the durability of components under dynamic load. Numerical simulations based on finite element (FE) models help with this understanding but must be validated by real component data. Polytec’s 3D Scanning Laser-Doppler Vibrometer with Strain Processor provides an advanced, non-contact optical test solution.

The package of Strain Processor in combination with a PSV-3D Scanning Vibrometers allow a non-contact, optical measuring alternative for dynamic stress and strain distribution and Finite Element model updates.

The Scanning Vibrometer makes a series of non-contact deflection measurements on a predefined grid using the laser probe to characterize strain at each point instead of attaching individual strain gauges. Thus, the test set-up is fast and very repeatable with no mass loading from an attached transducer. Tests are fast and avoid the high cost of preparing and instrumenting the sample with strain gauges.