DESC:F O R M 2
THE PATENTS ACT, 1970
(39 of 1970)
The Patent Rule, 2003

COMPLETE SPECIFICATION
(See section 10 and rule 13)

“A ROV system for underwater data processing and method thereof”
By
Planys Technologies Private Limited
An Indian company
03 - A2, 3rd Floor, IITM Incubation cell, Madras Research Park,
Kanagam Road Tharamani, Chennai,
INDIA - 600113

The following specification particularly describes the invention and the manner in which it is to be performed
FIELD OF THE INVENTION
The present invention relates generally to remotely operated vehicles (ROV’s) and more particularly to a ROV system and method for processing data underwater.
BACKGROUND OF THE INVENTION
Inspection class underwater vehicles are used to inspect immersed structure under water which can either be autonomous underwater vehicle (AUV) or remotely operated underwater vehicle (ROV). An inspection vehicle performs inspection by recording video/photo and streams it to pilot and upon pilot’s instruction performs activities like visual inspection, ultrasonic thickness measurement (UT), marine growth removal, cathodic potential measurement, SONAR surveys etc.
Conventionally ROV system consists of commanding station, and ROV connected by tether for power and communication. ROV consist of thruster (electric motor driven propeller used to move vehicle), camera (for video recording and providing live feed), Lights (LED Illumination under sea in case of poor visibility). Videos/Photos, vehicle parameters are transmitted through tether to control station and control station command the ROV through the tether. Tether act as transmission of power and communication means.
ROV falls under inspection class vehicles which can able to operate up to 250 meters of tether length. Underwater, vehicle need to pull 250 meter of tether under high water current and rough sea weather condition. To achieve this electronics and communication system need to be extremely robust on top of power and propulsion system. To overcome the very rough sea condition electronics system need to receive command from the pilot on control station, process it and make necessary action without any delay. If there is any delay in receiving the command and processing it to make necessary action, the pilot will lose the current ROV position under sea.
The rough environment beneath the sea/ocean with heavy water currents, waves, pressure will make the significant disturbance to the pilot to maneuver/control the ROV, which leads to increased data handling, data processing for effective control. For example, figure 1 is block diagram showing electronics architecture of the ROVs according to the existing technology. In this method all the sensors (Cameras, Thickness measurement, Sonars, Illumination, Pressure sensor, Altimeter etc) will get directly connected to the control station. Thus configuration requires higher number of wires in umbilical which leads to cost and complexity of the system. Further, data processing is performed in control station which leads to higher data transfer rate and high reliable communication bandwidth to achieve desired result which ultimately increases equipment cost, increases system complexity, increased data to handle.
Thus current communication technology for ROVs suffers in the area of communication bandwidth, data storage, processing pilot command and converting it to physical movement in the ROV and getting back data from different module in the ROV to again back to the control station for the analysis. Hence there is need for a system which is able to perform much better than available systems in minimum communication bandwidth which ultimately reduces equipment cost and provide superior performance.
OBJECTIVE OF THE INVENTION
These objectives are provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This objective are not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
An important objective of the invention aims at providing a compact solution for the shortcomings of the above mentioned systems.
Another objective of the invention is to process all the data in the underwater unit (ROV).
Yet another objective of the current invention to achieve command/data processing at zero time lag for superior performance.
Another objective of the invention is to use domestic power supply for ROV for both power and communication.
Further objective of the current invention is to provide control using three core tether to transmit power and communication.
Objective of the present invention is not limited to the above mentioned problem. Other technical problems that are not mentioned will become apparent to those skilled in the art from the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described in greater detail with reference to an embodiment which is illustrated in the drawing figures:
Figure 1 is block diagram showing electronics architecture of the ROVs according to the existing technology;
Figure 2 is block diagram showing electronics architecture of the present invention according to first aspect of the present invention; and
Figure 3 is block diagram showing electronics architecture of the present invention according to second aspect of the present invention.
Throughout the drawings, it should be noted that like reference numbers are used to depict the same or similar elements, features, and structures.
DETAILED DESCRIPTION OF THE INVENTION
A typical remotely operated underwater vehicle (ROV) system has a command station, a communication means and a ROV. The ROV contains various parts including a frame for providing mechanical support, plurality of thrusters, lights for illumination, a camera unit, and a pressure hull to hold and safeguard electronics associated with thrusters, lights, camera, and other payloads. Further, the command/control station arrangement consists of a multimedia screen to display videos, photos and various vehicle parameters, a joystick to control the ROV, a processor for processing the data and a communication adaptor for establishing communication means between control station and ROV. Communication means connects the command station to ROV to transmit power, and establishes communication between the ROV and command station for easy controllability of underwater unit, providing live stream data to the pilot on command station. The communication means can be a tether which is capable of transferring both power and data.
Figure 2 is block diagram showing electronics architecture of the present invention according to first aspect of the present invention. A ROV system for underwater data processing, comprising a plurality of processor modules or central processing unit (CPU), each processor module including means for generating concurrent data packets, wherein the data packets comprise serial sequences of data and an communication means coupled to receive and transfer the data packets from and to the processor modules. Said processor modules comprising a plurality of inter connected active logic decision means each including at least means for assigning priority based on data content between contending data packets. The decision means also including means for transferring data packets to which priority has been granted through the network without interruption while blocking transfer of data packets that lose in priority. The communication means including means for coupling the decision means in a converging array such that all concurrent data packets from the processor modules are placed in contention during transfer through the communication means and final priority decision is made within the communication means so that a single or common data packet is transferred to the processor modules based on the offered bandwidth. The processor module receives or transfers data with main controller board, power conversion unit, sonar unit, thickness measurement unit, etc. wherein each unit performing unique set of functions as alone or collectively.
Method of data processing in a ROV system comprising the steps of generating data packets by a plurality of processor modules, each processor module including means for generating concurrent data packets, assigning priority based on data content between contending data packets by means of plurality of inter connected active logic decision means each including at least means for granting priority based on data content between contending data packets, and transferring data packets as per priority assigned between through the communication means, wherein the communication means including means for coupling the decision means in a converging array such that all concurrent packets from the processor modules are placed in contention during transfer through the communication means and final priority decision is made within the communication means so that a single or common data packet is transferred to the processor modules based on the offered bandwidth.
When there is drop in communication bandwidth, the ROV system for underwater data processing is capable of achieving the same performance by changing the data packet/protocol being sent to the control station. Once bandwidth drops below predefined threshold value, processor selects the most important data packet to be transferred to control station to compensate the bandwidth drop, and also the data packet will be reconfigured based on bandwidth available. When, operational environment changes processor reconfigures to transfer the data to the control station quickly adapting to the subsea environment. Different communication methods/protocols are used over different units of the system to achieve performance.
Figure 3 is block diagram showing electronics architecture of the present invention according to second aspect of the present invention. Accordingly the present invention allows ROVs to achieve zero time lag between control station and ROVs to perform necessary actions. To achieve this superior performance at reduced cost, complex data is always being processed, stored in the underwater unit (ROV) to reduce transmission delays.
ROVs according to the present invention has onboard processer module which interacts with each and every units in the system, wherein processer module receives data from different units, all the received data is analysed and prioritised to transfer important data to the pilot as feedback. Further, all the additional payloads are connected to processor module and processor module gets connected to control station processor module via communication means. This provides modularity in the system as simple as connection between two computers where pilot at control station can remotely access other processor module and modify it on the run to do different jobs.
Advantages of the present invention are zero dead time in pilot command and ROV response, data processing and storing in underwater unit (ROV) for achieving high efficiency in collecting data from various sensors. Further, proposed ROV system is very compact compared to other inspection class ROVs, providing better controllability and performance even in rough sea conditions. Other advantages include use of commercial power supply for both power and communication with ROVs and reduced number of core of umblical/tether.
The present invention finds application in underwater inspection of any immersed structure at ports, terminals, harbour’s for breakwater inspection, jetty inspection, wharf inspection, riser inspection, dredging support, pre-dredging obstacles survey, bathymetry, in shipping for inspection of paint loss, ultrasonic thickness mapping, bio-fouling inspection, ship propeller inspection. Further applications include in oil and gas (offshore) industry for platform structure inspection, single buoy mooring inspection, submerged cable inspection, submerged pipeline inspection, pipeline survey, offshore installation support, in power production units for dam inspection, inspection for radiation leak, thermal plant tank inspection, and, also in scientific institutions for oceanographic sampling, seismic survey & bathymetry, archaeological survey.
Although but one preferred embodiment of the invention has been illustrated, it will be obvious to those skilled in this art that other embodiments may be readily designed within the scope and teachings thereof.
,CLAIMS:I/we Claim,
1. A ROV system for underwater data processing, comprising: a plurality of processor modules, each processor module including means for generating concurrent data packets; and an communication means coupled to receive and transfer the data packets from and to the processor modules, said processor modules comprising a plurality of inter connected active logic decision means each including at least means for assigning priority based on data content between contending data packets, the decision means also including means for transferring data packets to which priority has been granted and the communication means including means for coupling the decision means in a converging array such that all concurrent data packets from the processor modules are placed in contention during transfer through the communication means and final priority decision is made within the communication means so that a single or common data packet is transferred to the processor modules based on the offered bandwidth.
2. The ROV system according to claim 1, wherein said communication means is tether.
3. The ROV system according to claim 1, wherein the decision means include means for transferring those data packets having priority through the network without interruption while blocking transfer of data packets that lose in priority.
4. The ROV system according to claim 1, wherein the data packets comprise serial sequences of data.
5. A method of data processing in a ROV, comprising the steps of:
generating data packets by a plurality of processor modules, each processor module including means for generating concurrent data packets;
assigning priority based on data content between contending data packets, by a plurality of inter connected active logic decision means each including at least means for granting priority based on data content between contending data packets; and
transferring data packets as per priority assigned between through the communication means., wherein the communication means including means for coupling the decision means in a converging array such that all concurrent data packets from the processor modules are placed in contention during transfer through the communication means and final priority decision is made within the communication means so that a single or common data packet is transferred to the processor modules based on the offered bandwidth.
6. The method according to claim 5, wherein said communication means coupled to receive and transfer the data packets from and to the processor modules.
7. The ROV system according to claim 1, wherein the decision means include means for transferring those data packets having priority through the network without interruption while blocking transfer of data packets that lose in priority.
8. The ROV system according to claim 1, wherein the data packets comprise serial sequences of data.