Am. Crawford et Ae. Hay, A SIMPLE SYSTEM FOR LASER-ILLUMINATED VIDEO IMAGING OF SEDIMENT SUSPENSION AND BED TOPOGRAPHY, IEEE journal of oceanic engineering, 23(1), 1998, pp. 12-19
A simple underwater video system has been developed for simultaneously
imaging sediment suspension and monitoring bed profiles under waves a
nd combined wave-current hows, This consists of a diode-laser-generate
d light plane and a a black-and-white underwater video camera, The las
er light illuminates suspended material in section and also provides a
bed profile at the bottom, Orthogonal laser/camera pairs are used to
obtain both cross-shore and alongshore views. During deployments, the
system has been augmented by acoustic backscatter devices for measurem
ent of sediment concentration, As with all video techniques, visibilit
y is a limiting factor, but where turbidity is low to moderate, the re
sults are encouraging, Results on cross-shore and alongshore bed eleva
tion variations and suspension event scales obtained with the video/la
ser system are presented for two experiments: one at the National Rese
arch Council wave Research Flume in Ottawa, Canada, and the other in t
he field at Queensland Beach, N.S., Canada.