High speed 3D air-fluid interface sensor

 

Our 3D sensor technology is based on a stereo-photogrammetry approach. It includes a pattern projector, two cameras, two cameras are directed onto the water surface. Because of fluorescent dye of average concentration, the projector light is converted at the surface of the water. The two cameras take pictures of the water surface with differing statistical patterns from the projector illuminating it.

 

After capturing a sequence of images with both cameras, correspondence assignment is applied to the images to achieve many, accurately located homologous image points. Afterwards, the corresponding image points are triangulated with a preliminary calibration of the camera parameters. The obtained 3D points can now be taken for manifold investigations, dispersion relation, amplitude magnification and so on. 

 

The University of Nottingham and EnShape have submitted a joint-pattent application to protect our invention. If you are interested in purchasing our sensor, please contact EnShape. The first Hight speed 3D air-fluid interface sensor has now arrived in Nottingham. On this website we will document the arrival, setup and first results obtained with the newest member of QG-Lab.

The Ripple Catcher in action

The Ripple Catcher arrived

The Ripple Catcher arrived

The Ripple Catcher and the EnShape team arrived at QG-Lab. After a long train ride from Jena (Germany) to Nottingham (UK) the sensor works without any problems.

A closeup on the Ripple Catcher

A closeup on the Ripple Catcher

Sometimes beauty and functionality goes together.

Marcus in the spotlight

Marcus in the spotlight

Marcus Grosse (one of the founding members of EnShape) walks by our sensor with a white shirt. The color indicates the depths.

Up in the air

Up in the air

Everything - the sensor and the computer - has to be mounted 3 meter above grounds. From the left to the right: Marcus (EnShape), Terry Right (Nottingham University) and Tommy Napier (Nottingham University). Without Terry and Tommy this would have been impossible.

Teamwork completed

Teamwork completed

From the left to the right: Tommy Napier (Nottingham University), Daniel Goodfellow (PhD student Nottingham University), Simon (EnShape), Terry Right (Nottingham University), and Marcus (EnShape).

The Ripple Catcher flies high.

The Ripple Catcher flies high.

We - Tommy, Terry and QG-Lab - have designed a special carriage that can be moved in all 3 spatial dimensions above the free surface in our experimental setup.

Marcus

Marcus

Marcus Grosse is one of the two founding members of EnShape. The other is Martin Schaffer.

Simon

Simon

Simon Willeke from EnShape is responsible for all IT aspects related to our sensor.

Ripples in a white sheet

Ripples in a white sheet

The first test is on a solid surface, the result can be seen on the next image.

Well captured!

Well captured!

The Ripple Capture has passed all tests on solid surfaces, and we are ready to move on capture ripples in the air-fluid interface.

The Ripple Catcher applied to air-liquid interface

Water Vortex

Water Vortex

The Ripple Catcher is applied to the air-water interface of a bathtub vortex.

Fluorescent dye

Fluorescent dye

In order to capture the free surface we added fluorescent sodium salt. The blue LED excites the fluorescent dye and gets converted to green light.

Blue light turns green

Blue light turns green

Most the light gets absorbed by at the surface, but some of the light also illuminates the water vortex below the surface.

The Ripple Catcher on fluids

The Ripple Catcher on fluids

In the background one can see the vortex flow. In the foreground we see the reconstructed image of the air-water interface.

The Ripple Catcher scanning skulls...

Giraffe skull

Giraffe skull

Hartman Thomas and Thomas Napier asked us to scan this giraffe skull. We placed the skull in our tank directly under our Ripple Catcher.

The scanning process

The scanning process

We shine a random pattern onto the giraffe skull and record the images.

The scanning process continues

The scanning process continues

We repeat this procedure for various different positions of the skull.

Scanned giraffe skull

Scanned giraffe skull

Marcus Grosse (EnShape) put the various scanned files together to obtain a 3D scan of the giraffe skull.

Water Vortex

The Ripple Catcher is applied to the air-water interface of a bathtub vortex.