Figure 7 : A typical Dive Support Vessel deck layout .
Figure 8 : An example of a vessel deck layout .
It is important that the ROV engineers study the deck layout so that the intended work can be performed in a safe and effective manner . In some cases , ROV engineers are required to perform a deck calculation to check the strength and stiffness of the vessel ’ s deck . In the event , the ROV engineers find that the deck strength is not sufficient , the client will be required to find a replacement vessel .
The most important thing in the calculation is the deck loading ( in kg per sq m ) and the reaction forces from LARS mounting brackets .
When the deck of the vessel / oil rig is surrounded with a safety fence , the ROV engineers must design a raised platform to lift the ROV to an operable height .
When the client requires additional sensors or tooling equipment , the ROV contractor has to engage a tool rental company and the ROV engineer in charge must carefully check if the ROV is capable of taking on the additional equipment . He has to study the electrical schematic of the ROV whether there are sufficient connector outlets and electrical power to take the new tools and sensors . Examples of often requested additional sensors are a 3D sonar , an anode probe , a laser probe , a USBL , a fibre optical multiplexer and a multi beam sonar .
In most cases , the additional sensor can be interfaced with the existing ROV main control pod ( MCP ) by diverting the existing fibre optical signal cable , which acts as a primary telemetry signal from the control cabin to the ROV , to the new fibre optical multiplexer . The multiplexer is able to
Figure 9 : Reaction forces analysis on x , y and z directions of a LARS .
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