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)

“REAL TIME DATA PROCESSING SYSTEM FOR UNDERWATER MEASUREMENT AND A METHOD THEREOF”
By
Planys Technologies Private Limited
An Indian company
03 - A2, 3rd Floor, IITM Incubation cell, Madras Research Park, Kanagam Road Tharamani, Chennai 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 data processing system and more particularly to real time data processing system for observational class remotely operated vehicles (ROVs) intended to measure subject of interest in an underwater structure.
BACKGROUND OF THE INVENTION
In general every immersed structure over the time gets damaged or deteriorated either because of natural environmental factors or unusual loading conditions which leads to overstress which eventually leads to cracks on the structure. To avoid any kind of catastrophic damages, these issues needed to be visually monitored and requires regular maintenance. So, it is very important that methods used in measuring the scale of damage should follow standards and verified by experts.
Traditional methods of inspection include divers capturing the videos of the immersed structures and all the measurements are done by the divers. As these are manually inspected and measured there is always space for manual errors and the precision of measurements are constraints by technical expertise of the divers.
Even though ROVs are more commonly used for underwater measurement they remain impeded by difficult in viewing the objects when the camera in the shallow deep or lights are scattered due to particles such as silt. Thus, viewing in underwater is completely impeded and makes difficult for ROV operator to control and completion of the task.
Further, any visual survey done in shallow waters especially below 20 meters from the water surface will be affected by the sunlight. Most of the light spectrum is absorbed in this region of 20 meters which makes captured images or videos single hue layers. To get the original images or videos filters should be added and needs calibration of white balance.
Other drawback includes, when two lasers are projected on a surface, finding the real/original distance between the projected points of laser is also complex, and one has to consider the angle of projection in 3D space, which is not so easy to perform.
Thus, the current innovation is focused on addressing the above mentioned drawbacks by providing a real time visual feed of immersed structures with added filters to counter the visual imbalances induced by the liquid in which structures are immersed. And also to measure, and analysis the diameter of immersed structures or the thickness of a crack in concrete structures without physically contacting any objects underwater.
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 present invention is to display as well as record the underwater visuals in the real time.
Yet another objective of the present invention is to enhancement of visionary for underwater objects in shallow depth and low light environment.
Further objective of the invention is to eliminate the possibility of any human errors in measurements and analysis.
Yet another objective of the present invention is to measure and analysis the crack in the immersed objects and structures without physically contacting any objects in underwater.
Another objective of the present invention is to counter the visual imbalances induced by the liquid in which structures are immersed.
Yet another objective of the present invention is to eliminate the impact of roll angle in the measurements.
These objectives are achieved according to the invention a real time data processing system for measurement of an underwater structure, comprising of a platform for supporting and conveying the imaging system, an imaging system coupled to said platform and adapted to disposed between plurality of light source such that said light source are positioned at measured distance imaging frames of said underwater structure, a data processing system in communication with the imaging system processing and measuring the frames, a tether connecting and transmitting data between the data processing system and a pilot computer, and a graphic display means in the pilot computer converting said digital representation into a visual representation of said structure for analysing underwater measurement of immersed structures.
Object 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 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 a pictorial illustration of real time data processing system, according to an embodiment of the present invention;
Figure 2 shows schematic setup of LASER assisted measurement system, according to an embodiment of the present invention;
Figure 3 shows position of ROV with LASERs against a subject of interest in different embodiments (i) shows LASERs projected perpendicular to subject surface, (ii) shows LASERs projected at an inclined angle ? with subject surface; and
Figure 4 shows trigonometry of LASER beams projected on subject surface with visual angle, according to an embodiment 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
The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the invention as defined by the claims and their equivalents. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the invention. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness.
In the claims, all transitional phrases such as "comprising," "including," "carrying," "having," "containing," "involving," and the like are to be understood to be open- ended, i.e., to mean including but not limited to. Only the transitional phrases "consisting of and "consisting essentially of," respectively, shall be closed or semi-closed transitional phrases.
To facilitate the understanding of this invention, a number of terms may be defined below. Terms defined herein have meanings as commonly understood by a person of ordinary skill in the areas relevant to the present invention. Terms such as "a", "an", and "the" are not intended to refer to only a singular entity, but include the general class of which a specific example may be used for illustration. The terminology herein is used to describe specific embodiments of the invention, but their usage does not delimit the disclosed system or method, except as may be outlined in the claims.
Figure 1 is a pictorial illustration of real time data processing system, according to a preferred embodiment of the present invention. A real time data processing system 100 for measurement of an underwater structure comprises a platform 102 for supporting and conveying the imaging system 108. The platform 102 can be selected from the group consisting of AUV’s and ROV’s for the operation. Further the system 100 has an imaging system 108 coupled to said platform 102 and adapted to disposed between plurality of light source 128 such that said light source 128 are positioned at measured distance imaging frames of said underwater structure 132. The imaging system 108 consists of an optical lens 108A for capturing the images and a frame grabber 108B for grabbing frames from the optical lens 108A. The imaging system 108 is coupled to a data processing system attached to the platform 102 for processing and measuring the frames. The data processing system according to the system 100 comprises a camera programmable circuit 110, and a ROV processor 112 and/or a distance measuring processor 126 which are operatively connected with a memory 114. The corresponding figure 2 shows the schematic setup of LASER assisted measurement system, according to an embodiment of the present invention.
A tether 104 connects and transmits the data between the data processing system and a pilot computer 120. Tether 104 carries AC power along with the network data on a single line tether 104. The data transmission between the data processing system and the pilot computer 120 involves a ROV PLC 116 having an ROV adaptor converting said data in digital representation to analog signals and encoding the signals for transmitting the signals over tether 104, and a pilot adaptor of a pilot PLC 118 receiving and decoding said analog signals to digital representation of said structure. And a graphic display means in the pilot computer 120 for converting said data in digital representation into a visual representation of said structure 132. The pilot computer 120 according to the present system 100 is employed offshore for receiving or sending the command signal from/to ROV 102. Command to the pilot computer 120 can be given by ROV operator or pilot through any input modes 122 viz. mouse, keyboard etc.
According to the present invention, real time data processing method for measurement of subject of interest in an underwater structure is a mixture of image processing and trigonometry concepts.
The real time data processing method for measurement of an underwater structure comprises the steps of emitting from a light source viz. LASERs a beam of collimated light on the subject surface of underwater structure to be measured, and imaging the subject surface with at least one imaging system. The imaging system generates a continuous data frame of subject surface. The generated data includes images and/or video frames captured underwater. Underwater structure can be anything but not limited to the group consisting of a sea floor, objects resting on the sea floor, tethered objects, ship’s hulls, seawalls, and floating objects, etc. And the imaging system can be a camera, or camcorder, or mobile, or any known device capable of capturing videos.
Further steps includes identifying the region of interest (RoI) in the generated data frame and applying color space for enhancing the visibility of the LASERs on the frame. The enhanced data is converted to produce a digital representation of data of said underwater structure, wherein the digital representation is a low voltage differential signal (LVDS). Further, the digital representation data is enhanced in real time through a camera programmable circuit, wherein the step of enhancing and optimizing the parameters of digital representation includes applying morphing techniques for enhancing the LASERs image location on the data. The morphing techniques include dilation for removing the left out unwanted pixels remaining on the digital representation data and erosion for filling the color and enhance the visibility of LASERs on the digital representation data. Applying morphing techniques enhances LASERs image location on data such that LASERs on data is represented as plurality of blobs.
Further, said data is processed in a ROV processor and transmitted to the memory for storing and streaming for real time visualizing the signal for ROV operator, wherein the data is transmitted to display monitor through a pair of power line communication’s (PLC’s) viz ROV PLC and pilot PLC, where data is decoded and displayed for analyzing the underwater structures. Alternatively, the data in digital representation is employed for measuring and analyzing the dimension parameters of subject surface by a distance measuring processor. The step of measuring dimension parameters of underwater structure by a distance measuring processor includes detecting blob and identifying center point location on the digital representation and calculating the pixel value between the center point location and converting the pixel value to real time distance measurement.
From the figure 2, two solid parallel lines represent view of LASERs projected and two thin lines represent the camera view of the same LASER beams. The solid lines are parallel and thin lines appear to be merging at some point. The merging of lines is because of the visual angle which brings the principle of linear perspective into consideration.
If ‘z’ is the true dimension of the subject of interest, ‘a’ is the distance between the light source, ‘d’ is the apparent dimension of the subject of interest / distance between the light source measured in pixels, ‘h’ is the perpendicular distance between the imaging system and the underwater structure, and ‘?’ is the angle between the imaging system with the underwater structure. Then the true dimension of the subject of interest is calculated according to the linear perspective principle in accordance with the following formulae:
a=h*d
a = z when (? = 90°)
Figure 3 shows position of ROV with LASERs against a subject of interest in different embodiments (i) shows LASERs projected perpendicular to subject surface, (ii) shows LASERs projected at an inclined angle ? with subject surface.
In embodiment (i) LASER beams are projected perpendicular to the subject surface and from the captured data number of pixels between pointed LASER beams is calculated. Further, from the calibration data of lasers with known distance and respective pixel numbers correlated the extracted number of pixels to the true scale of measurements to find the true dimension of subject of interest. The true dimension of the subject of interest is calculated in accordance with the following formulae is:
a=h*d
In embodiment (ii) LASERs beams are projected at an inclined angle ? against the subject surface, to find the true dimension of the subject of interest. Accordingly figure 6 shows trigonometry of LASER beams projected on subject surface with visual angle, according to an embodiment of the present invention. Where, projection length of AB on the wall at angle ? follows sine curve this implies that the length FE also follows the sine curve. So, when trying to measure the length of a crack at a distance ‘h’ from the camera lens, extracting few sample d values using the image processing and number of pixels with varying angle in XY plane that is varying yaw angle ?. These samples are extrapolated to get the value of d at the angle 90 degrees which gives the true distance. The true dimension of the subject of interest is calculated in accordance with the following formulae is:
a=h*d
and the true length is z = (a/sin?)
a = z when sin? is 90°
The present invention can be employed for measurement of subject of interest including but not limited to crack length, pile diameter analysis and various assessments on targeted underwater structures under varying working conditions including different water colors, water temperature, lighting environment, distance, depth and varying density.
While imaging the data multiple illuminations can be generated through the programmed electronic camera circuit on real time. A ROV operator can choose the better and appropriate view. Simultaneous actions of displaying data of the subject surface through display monitor and recording on memory also takes the illumination effects.
View from the imaging system can be enhanced by applying various enhancement tools available for pilot through selecting from the various available views which is selected by operating pilot. The parameters that can be enhanced include color gain, image brightness, camera exposure, defog, color enhance of (Y, Cr and Cb), Hue settings, IR Correction etc. Different views are generated by the various filters applied through the computer programs as well as in the circuits of the camera. Thus filtered video signals are incorporated in the display monitor in real time.
The present invention described displays as well as records the underwater visuals in the real time. This invention also enhances the visionary for underwater objects in shallow depth and low light environment. The real time data processing system is specifically created for underwater environment for capturing high quality frames at optimum fps devised in a way that the customer can view the data in any computer/mobile/any personal device.
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,
A real time data processing system for measurement of an underwater structure, comprising:
a platform for supporting and conveying the imaging system;
an imaging system coupled to said platform and adapted to disposed between plurality of light source such that said light source are positioned at measured distance imaging frames of said underwater structure;
a data processing system in communication with the imaging system processing and measuring the frames;
a tether connecting and transmitting data between the data processing system and a pilot computer; and
a graphic display means in the pilot computer converting said digital representation into a visual representation of said structure.
The real time data processing system according to claim 1, wherein the data processing system comprising a camera programmable circuit, and a ROV processor operatively connected with a memory.
The real time data processing system according to claim 1, wherein the data transmission between the data processing system and the pilot computer involves a ROV PLC having an ROV adaptor converting the data in digital representation to analog signals and encoding the signals for transmitting the signals over tether and a pilot adaptor of a pilot PLC receiving and decoding the analog signals to digital representation to display visual representation of said structure.
The real time data processing system according to any of the above claim, wherein said data processing system is attached to the platform.
The real time data processing system according to claim 1, wherein the platform is selected from the group consisting of AUV’s and ROV’s.
The real time data processing system according to claim 1, wherein said imaging system comprising an optical lens and a frame grabber.
The real time data processing system according to claim 1, wherein the light source is a LASER.
The real time data processing system according to claim 1, wherein underwater structure is selected from the group comprising of a sea floor, objects resting on the sea floor, tethered objects, ship’s hulls, seawalls, and floating objects.
The real time data processing system according to claim 1, wherein data including images and/or video frames.
A real time data processing method for measurement of subject of interest in an underwater structure, comprising the steps of:
emitting from a light source a beam of collimated light that is projected on the subject surface to be measured, and imaging the subject surface with at least one imaging system mounted on ROV for continuous data frame;
identifying the region of interest (RoI) in the captured data frame and applying color space for enhancing the visibility of the light source on the frame;
producing a digital representation of data frame of said underwater structure, wherein the digital representation is a low voltage differential signal(LVDS);
enhancing and optimizing the parameters of digital representation data through a camera programmable circuit;
transferring said data of said underwater structure to a memory;
storing said digital representation of said data in said memory;
measuring dimension parameters of underwater structure by a distance measuring processor;
transmitting said digital representation of said subject surface to display monitor through a pair of power line communication’s (PLC’s); and
decoding and displaying the digital representation for analysing the underwater structures.
The method of claim 10, wherein the step of enhancing and optimizing the parameters of digital representation includes applying morphing techniques for enhancing the light source image location on the data.
The method of claim 11, wherein the morphing techniques includes dilation and erosion.
The method of claim 10, wherein the step of measuring dimension parameters of underwater structure by a distance measuring processor includes detecting blob and identifying center point location on the digital representation and calculating the pixel value between the center point location and converting the pixel value to real time distance measurement.
The method of claim 10 wherein the step of measuring dimension parameters of subject of interest in a underwater structure further includes a calculation step conducted in accordance with the following formulae:
a=h*d
and the true length is z = (a/sin?)
and wherein:
‘a’ is the true dimension of the subject of interest,
‘d’ is the apparent dimension of the subject of interest,
‘h’ is the perpendicular distance between the imaging system and the subject of interest, and
‘?’ is the angle between the imaging system with the underwater structure, wherein a = z when sin? is 90°
Dated this the 14th day of December, 2017