Current status in development of averaging laser strainometer and testing system

The advent of a new method of sweeping a laser beam to accurately measure a shadow image offers unique applications to mechanical testing. A new commercial low power continuous wave laser system designed for metrological applications is being applied to the testing of a delicate, brittle, notch sensitive, hygroscopic material requiring dry box enclosure. An integrated testing system is being developed to provide remote strain sensing of minimum, maximum, and average surface strains on the cylindrical portion of a compression specimen. The system additionally provides the means to compensate for bending strains observed in pretest alignment evaulation. The results of the development of the testing fixture to date are discussed.