With investigations using realistic models of flowing waters, the river bed must be sampled as accurately as possible and without physical contact. To do this, the laser-based optical displacement measurement system, optoNCDT, is used which
features high accuracy with a large measuring range and is largely independent of the ground conditions. It is mounted together with the signal conditioning electronic unit on a measurement carriage movable in the X direction which is suspended from a traversing beam movable in the Y direction. The distance to the water surface is acquired simultaneously with a parallel-mounted ultrasonic displacement system.