1. TMR4225 Marine Operations, 2004.03.11 ROV systems:
Umbilical
Control system
MINERVA drag characteristics
STEALTH hydrodynamic characteristics
ROV simulators
Future challenges

2. ROV umbilicals
Vessel motion and induced motion at upper end of umbilical
Umbilical geometry resulting from depth varying current
Use of buoyance and weight elements to obtain a S-form to reduce umbilical forces on the ROV
Induced transverse vibrations of umbilical
Forces and motions at lower end of umbilical

3. MINERVA tests Drag tests,varying speed
Drag test, varying angle of attack
Full scale tests
Use of vehicle to generate input to parametric identification of mathematical model characteristics
A possible project involving NTNU, Marine Cybernetics and Sperre?
Exercise no.5 includes comparison of own calculations with model test results for MINERVA

4. STEALTH 3000 characteristics
Dimensions
Length: m
Breadth: m
Depth: m
7 horizontal and 3 vertical thrusters
Thruster pull and speed values:
1200kgf forward/aft, 5 knots forward, 3 knots reverse
500 kgf lateral, knots lateral
1000 kgf vertical, knots vertical

5. Hydrodynamic analysis of STEALTH
MSc thesis on ”Manoeuvrability for ROV in a deep water tie-in operation”
Simplified geometries used when estimating added mass coefficients based on work by Faltinsen and Øritsland for various shapes of rectangular bodies
Quadratic damping coefficients used, corrections made for rounding of corners based on Hoerner curves
Maximum speed as a function of heading angle has been calculated using simplified thruster model

6. ROV operational challenges
Surface vessel motion
Crane tip motion
Umbilical geometry and forces
ROV hydrodynamic characteristics
Influence of sea bottom
Interference from subsea structures
ROV control systems

7. ROV simulator – systems requirements
System requirements give DESIGN IMPLICATIONS with respect to:
Simulation software
Computer hardware architecture
Mechanical packaging
See article by Smallwood et. al. for more information
A New Remotely Operated Underwater Vehicle for Dynamics and Control Research

8. System requirement - Example
Simulate a variety of ROV design configurations for both military and commercial mission applications
DESIGN IMPLICATIONS for simulation software:
Sensor databases must include a wide range of underwater objects
Modular model for ROV hydrodynamics
Standard protocols for information exchange between modules
DESIGN IMPLICATIONS for mechanical packaging
System must be reconfigurable to replicate a wide range of control/operator console layouts.

9. Buzz group question no. 1:
List functional requirements for a ROV simulator to be used for accessability studies
Student responses:
Easy integration of different kinds of underwater structures
Easy implementation of different ROVs
Easy implementation of different types of sensors
Realistic model of umbilical
Catalogue of error modes and related what –if statements
Ability to simulate realistic environmental conditions, such as reduced visability and varying sonar conditions

10. Buzz group question no. 1 (cont):
Realistic simulation of different navigation systems
Obstacle recognition and handling
Easy input interface for parametres related to ROV geometry, environment, navigation systems and different work tools
Realistic model for calculation of ROV motion
Good interface for presentation of ROV position and motion, including available control forces (Graphical User Interface, GUI)

11. Simulator design
A modular design will make it easy to change modules for different subsystems of a ROV, subsea structures etc
The simulator should allow both real time and fast time simulation
High Level Architecture (HLA) is used for defence simulators to allow different modules to communicate through predefined protocols
Marine Cybernetics uses:
SH**2iL as their structure for simulators (Software-Hardware-Human-in-the-Loop)

12. Simulator design (cont.)
Check
for their modular simulator concept or

13. Necessary improvements for advanced ROV operations
3D navigational tools
3D based planning tools
Digital, visual ”online” reporting
Realistic simulator training for pilots
Access verification using simulator during the engineering phase of a subsea operation involving ROVs
Central placed special control room

14. Challenges for future ROV operations
Better visualization for pilot situational awareness
Better planning of operations, for instance through use of simulator in the engineering design and development of operational procedures
Better reporting system, including automatic functions to reduce the workload of the ROV pilot
Closer co-operation between ROV pilot and subsea system experts in a central on shore operations control centre

15. Oceaneering - ongoing work
MIMIC
Modular Integrated Man-Machine Interaction and Control
VSIS
Virtual Subsea Intervention Solution