Functional testing using rapid prototyped components and optical measurement

Rapid prototyping manufacturing methods such as stereo-lithography, fused deposition modelling, enable real parts to be produced very quickly from CAD models but because the parts are produced in materials which are different from the final component, these cannot readily be used for assessing structural integrity. Electronic speckle pattern interferometry (ESPI) enables full-field measurement of surface displacements, both static and dynamic to be made rapidly. This paper proposes the use of these two techniques together to enable the response of parts to static and dynamic loading to be assessed early on in the design process. It should be possible to make a qualitative assessment by observing the form of the deformation or vibration pattern produced and it may also be possible to make quantitative measurement by developing suitable scaling methods. Some initial experiments have been made looking at the vibration of flat plates and further proposed work is outlined.

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