VAMAS TWA26: First Questionnaire

VAMAS TWA26: First QUESTIONNAIRE about the use of optical strain measurement in industry

Results presented on SEM conference 2000, June 5-8 , Orlando (Florida, USA)

Project title :

The industrial requirement of standards for the use of

full field optical methods of stress and strain analysis

Sample statistics :

Users of optical NDI methods: 23 answers

Non-users of optical methods: 5 answers

NOTE about diagrams : %-values mean part of all answers , simple values mean nr. of answers

Optical Methods for Strain Measurement (Details) :

Photoelasticity, manual (reflection and transmission; stress frozen and 2-D)

Photoelasticity, automated (reflection and transmission; stress frozen and 2-D)

Gratings, low resolution (video based observation of prepared gratings, or similar)

Gratings, high resolution (spectral observation of diffractive gratings, or similar)

Moiré Methods (interferometric and geometric; shadow, reflection)

Image Correlation (video based observation of a surface structure)

Laser speckle or correlation methods (single or multiple focussed laser spots)

Laser speckle and interferometric methods, holography-like (ESPI, DSPI)

Laser speckle and interferometric methods, shearography-like (DSSPI)

Laser scanning methods (laser beam scanning over markings)

Thermoelasticity, scanning beam (S.P.A.T.E.)

Thermoelasticity, full field (using camera with focal plane array, FPA)

Different comments from users or non-users:

Computer based testing is insufficient to satisfy FAA/CAA

We would like to use optical methods, but the lack of generally accepted guidelines make it difficult to get regulatory authorities to accept results

Serious problem on educational level (lack of specialised training at most universities; only a few exceptions)

There are some here that would claim that they could use computer methods only, since "politically correct" answer, but not in my lifetime !

This is my opinion, but not necessarily fully supported by management (use of full field methods is essential to ensure the technical capability of our company) ...

All details of the outcome of this questionnaire remain anonymous.

Evaluation done by Michel Honlet and Richard Burguete. Last updated on 29.06.2000

For any further questions related to this first or future questionnaires please contact :

Michel Honlet
mail@honlet.com
phone: +49-7302-919056
fax: +49-7302-919057

For any further questions related to the standardisation of full-field optical methods for strain and stress analysis, especially in the scope of the technical work area (TWA) 26 of VAMAS, please look at :