CDOC..CodaOctopus Echoscope Article Terra Et A

CDOC..CodaOctopus Echoscope Article

Terra Et Aqua
Number 131 - June 2013

INNOVATIVE DESIGN, TECHNIQUES AND EQUIPMENT AT MAASVLAKTE 2, PORT OF ROTTERDAM
ERIC PEETERS

Exerpt…Below the water surface, where the majority
of the blocks are located, the operators had
no visual information which made it extremely
difficult to position the ripper tool correctly
around the block. In particular the danger was
that the ripper tool would be damaged by
moving blocks. From the start it was clear that
a normal underwater camera system would
not be a solution in the murky waters that
surround the breakwater and that an acoustic
viewing system would be necessary. At the
Ras Laffan Northern Breakwater project both
Boskalis and Van Oord had gained experience
in safely and accurately placing 37,000 single
layer armour protection units, called
AccropodesTM, with help of a Coda Octopus
3D Echoscope system. This innovative solution
resulted in increased production efficiency
while at the same time safety was improved.
The same technique was adopted on the
Maasvlakte 2 project.
The Echoscope generates over 16,000 beams
and has an opening angle of 50º (375 kHz) in
both horizontal and vertical directions producing
instantaneous three-dimensional sonar images
of both moving and stationary objects. The
Echoscope is mounted in a frame that is attached
to the front of the pontoon of the backhoe .
The frame is equipped with two electrical
servo motors which can follow the position of
the ripper tool in the horizontal plane (yaw)
and vertical plane (pitch). The automated
tracking of the ripper tool is controlled from
the Crane Monitoring System (CMS).
Within the system certain parameters can be
set to prevent the frame tracking the ripper
tool when it only moves a few degrees or is
lifted out of the water. For this specific job a
new feature was added – the Echoscope-UISTM
software – to present the stick and ripper tool
as 3D models with information from the CMS.
This additional information was especially
useful to the operators of the backhoe as it
gives a clear picture of the position of the
ripper tool with reference to the acoustic
presentation of underwater objects (Figure 25).