Application of a line laser scanner for bed form tracking in a laboratory flume

In order to develop a measurement method that is fully non-invasive and able to capture the short timescale bed-form dynamics, tests have been performed with single-beam (Visconti et al., 2012) and multi-beam (Friedrichs and Graf, 2006; Peña González et al., 2007) laser scanners. However, these studies have only focused on a laser beam travelling vertically downward up till now. In the present study the full range of beams emitted by a multi-beam laser is taken into account, and corrections are quantified and performed in order to reduce the errors due to e.g. refraction. The applied corrections are used for measuring dunes and alternate bars under flowing water conditions.