|
Seaeye ROVs
The navigation bar opposite lists the full range
of standard Seaeye ROVs that are available to choose from
to meet your particular operational requirements.
Having selected the most appropriate system your
next consideration will be how it is to be deployed and operated.
In principle there are two choices:
- To Free Swim the ROV or
- To deploy the ROV from a Tether Management System (TMS)
FREE SWIMMING SEAEYE ROVs
The following sketch illustrates the simplicity
of the lowest cost method of operating a Seaeye ROV - 'Free
Swimming' - and the minimum equipment needed to make up a
complete free swimming Seaeye system.
The External Power Supply required for
all Seaeye systems, (except for the Seaeye Falcon that uses
single phase AC) is 3 Phase AC of between 380 to 480 vac.
The Surface Power Supply Unit is connected
to the external power supply and provides the system with
the various supplies required as well as line insulation monitors
for safety.
The Surface Control Unit is connected
to the Surface Power Supply Unit and contains all of the control
electronics for the system. This unit can be free standing
and located on a convenient desk top or can be fitted into
a 19 inch rack mount system in more permanent installations.
This unit also provides the outputs from video, sonar and
other sensors that may be fitted to the ROV. The comprehensive
Seaeye video overlay is incorporated in the Surface Control
Unit as standard for all Seaeye ROVs.
A Video Monitor or video suite including
a video switcher, video recorders and monitors are connected
to the Surface Control Unit. The ROV's camera(s) are routed
to the monitor(s).
The Hand Controller used by the ROV pilot
to 'fly' the ROV as he views the video monitor and other sensor
information displayed on the video overlay, is connected to
the Surface Control Unit by a 5 metre lead. All of the vehicle's
control functions are incorporated in the Hand Control Unit.
These include camera pan and/or tilt, autopilot functions,
thruster trim controls, speed, direction, dive, surface and
lighting intensity. Spare capacity for additional control
functions is included.
An Umbilical connects between the Surface
Control Unit and the ROV. For free swimming applications a
tough, flexible, polyurethane sheathed umbilical is used.
The umbilical contains power conductors to the ROV as well
as control signal and video conductors. Spare conductors are
provided for accessories such as sonar, survey sensors, CP
probes and tools.
Launch and Recovery. The umbilical cable
is designed to lift the ROV during the launch or recovery
stages. It can be stored on a winch fitted with a slip ring
for this purpose. However some operators save the cost of
a dedicated winch and use a warping drum to take the weight
of the vehicle during this process. The umbilical is coiled
in a figure of eight to avoid any kinking and is then led
to the warping drum from which it passes over an umbilical
sheave to the ROV. When the ROV has been launched and sufficient
umbilical has been deployed, the umbilical can be 'stopped'
by taking a reverse turn on the warping drum.
The Umbilical Sheave can be fitted to
a conveniently located ship's crane, davit or 'A' frame. In
order to avoid damage to the umbilical, the sheave wheel must
have a greater radius than the minimum bend radius of the
umbilical.
TMS DEPLOYED SEAEYE ROV SYSTEMS
The following sketch illustrates a Seaeye ROV
system deployed using a Tether Management System (TMS) and
the additional equipment required. (A TMS is not available
for the Seaeye Falcon ROV that is normally hand launched and
operated free swimming):
A Tether Management System (TMS) comprises
a remotely controlled tether cable spooling mechanism fitted
into the top section of a side entry garage containing the
ROV. The TMS is lowered to the required working depth where
the ROV can be flown out of its garage to the extent of its
tether cable.
A ROV Lift Winch, capable of lifting and
deploying the combined weight of the ROV in the TMS as well
as recovering the weight of the armoured umbilical is needed
for these systems.
The Armoured Lift Umbilical replaces the
soft umbilical used for free swimming operations and is designed
to lift and deploy the combined weights of the TMS and ROV.
This cable carries an increased number of power conductors
to minimise the voltage drop between the surface and the ROV
allowing the vehicle to be operated to greater depths.
An 'A' Frame can be provided with the
ROV Lift Winch as a combined Launch and Recovery System (LARS),
package. Alternatively the ship's 'A' Frame or suitable crane
can be used with the addition of an Umbilical Sheave to deploy
the TMS.
The benefits of a TMS system include:
- Operations to greater depths
- Elimination of the effect of considerable drag forces
on the umbilical at greater depths
- Protection of the ROV during launch and recovery through
the splash zone
- Faster deployment to the working depth governed only by
the speed of the winch rather that the rate at which a free
swimming ROV could dive using its vertical thruster(s).
- A safe haven at depth for the ROV between tasks.
Full Specifications of Seaeye TMS Systems are provided
at the Seaeye TMS systems section.
|
