ASDEC uses the latest state-of-the-art laser vibrometry equipment and technology manufactured by Polytec in Germany. The 3D laser measurement heads are mounted on a Kuka industrial robot which in turn mounts on a traversing platform to enable large objects to be measured and extensive data sets to be captured quickly.
A series of shaker units enable different excitation regimes to be generated to mimic test or usage conditions, and the system is supported on an isolating floor to ensure maximum precision. The entire system is housed within a dedicated facility with sound proofing and confidentiality barriers.
As part of the process we study an object or an environment’s attribute of Noise and Vibration performance (most commonly abbreviated to Noise, Vibration & Harshness (NVH) in the automotive industry) using two software packages from Leuven Measurement Systems (LMS) now part of Siemens. We use LMS Test.Lab to analyse data obtained from the Polytec system for a structure and create a mathematical model of its dynamic or vibrational behaviour; and LMS Virtual.Lab is used as a bridge between the virtual and experimental world, where we can compare and correlate Finite Element (FE) models with experimental data.
The laser Doppler vibrometry system is able to sense to within 0.02 µm/s
Spatial resolution of data points depends on the distance of the measurement laser heads. Maximum resolution is 8 microns under certain conditions, with 50-100 microns achievable in normal use
The laser uses eye safe He-Ne lasers with a (visible) wavelength of 632.8nm. Because the system uses an interferometric Doppler shifted configuration it is able to resolve beyond the wavelength of light.
Near D.C – 1MHz