Stereoscopic measurement of free surface flows

Abstract

The present paper adresses the problem of combined three-dimensionnal measurements of shape and velocity of moving free surfaces. A measurement method based on the cross-correlation of image pairs obtained from a calibrated stereoscopic vision system is presented. The underlying concept of the method consists in the generation of parametric shape and displacement forms which are directly projected on the camera models. This procedure is then integrated in an iterative optimization process so that elevation, orientation, curvature and displacement of each surface subset are accurately estimated. Application is made on inclined plane flows of complex non-Newtonian fluids as an alternative to conventionnal rheometric devices.