Multichannel fiber laser Doppler vibrometer studies of low momentum and hypervelocity impacts

Abstract

A multichannel optical fiber laser Doppler vibrometer was demonstrated with the capability of making simultaneous non-contact measurements of impacts at 3 different locations. Two sets of measurements were performed, firstly using small ball bearings (1 mm-5.5 mm) falling under gravity and secondly using small projectiles (1 mm) fired from an extremely high velocity light gas gun (LGG) with speeds in the range 1 km/s-8 km/s. Determination of impact damage is important for industries such as aerospace, military and rail, where the effect of an impact on the structure can result in a major structural damage. To our knowledge the research reported here demonstrates the first trials of a multichannel fiber laser Doppler vibrometer being used to detect hypervelocity impacts. (J.E. Posada-Roman), d.a.jackson@kent.ac.uk (D.A. Jackson), m.j.cole@kent.ac.uk (M.J. Cole), jsouto@ing.uc3m.es (J.A. Garcia-Souto). Optics and Lasers in Engineering xxx (xxxx) xxx-xxx 0143-8166/

Development of a High-Resolution All-Fiber Homodyne Laser Doppler Vibrometer

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Six-beam homodyne laser Doppler vibrometry based on silicon photonics technology

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