Digital image correlation measurements of jaw bending in living stag beetles

Male stag beetles have extremely long jaws that they use as weapon gear in aggressive battles over mating rights. We performed Digital Image Correlation (DIC) measurements on living stag beetles. Only recently, DIC is being used for in vivo measurements. The challenge was to capture the very fast, transient deformations of the jaws during voluntary bites of the beetles (only 0.133s +/- 0.045s from bite onset until maximal bite force). The deformations of the male jaws were recorded by two high speed video cameras (250 frames s(-1)) while the beetle bit the bite plates of a force transducer. The strain calculations were too noisy to be interpretable. This was caused by the limitations of recording at a high frame rate (a lower resolution and a small depth of field owing to the wide aperture because of the limited light) and the jaw shape (small strain window because of the elongated jaw shape). We suggest technical improvements to the bite set-up and the image capturing to circumvent this problem by using a triggered setup. Nevertheless, our DIC measurements were very suitable to calculate jaw bending from the displacement data and we successfully validated a Finite Element model of a male jaw with these repeatable measurements. Therefore, we conclude that DIC is a valuable technique for in vivo deformation measurements and validation of Finite Element models. The implementation of high speed cameras or event triggered image capturing make DIC suitable to measure fast and transient phenomena.

Jaar van publicatie:2016

Trefwoorden:P1 Proceeding

BOF-keylabel:ja

Authors from:Higher Education

Toegankelijkheid:Closed