Single‑camera 3D PTV using
particle intensities and structured light

Andres A. Aguirre-Pablo, Abdulrahman B. Aljedaani, Jinhui Xiong, Ramzi Idoughi, Wolfgang Heidrich, Sigurdur T. Thoroddsen
Experiments in Fluids (2019)

Left: Experimental setup, showing the orientation of the camera and the illuminating projector. Note the intensity-gradient direction is in the depth direction with respect to the camera. Right: Reconstructed rotating flow pathlines of 960 unique particles, colored by the velocity magnitude in mm/s.


We use structured monochromatic volume illumination with spatially varying intensity profiles, to achieve 3D intensity particle tracking velocimetry using a single video camera. The video camera records the 2D motion of a 3D particle field within a fluid, which is perpendicularly illuminated with depth gradients of the illumination intensity. This allows us to encode the depth position perpendicular to the camera, in the intensity of each particle image. The light intensity field is calibrated using a 3D laser-engraved glass cube containing a known spatial distribution of 1100 defects. This is used to correct for the distortions and divergence of the projected light. We use a sequence of changing light patterns, with numerous sub-gradients in the intensity, to achieve a resolution of 200 depth levels.


paper          [Aguire-Pablo2019SingleCameraPTV.pdf (6.9MB)]