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 system and method for real-time ultrasonic thickness measurement of immersed structures”
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 a system and method for ultrasonic thickness measurement and more particularly to a real-time ultrasonic thickness measurement system for measuring thickness of immersed structures without making contact with target specimen, developed to support inspection by means of submersible ROVs.
BACKGROUND OF THE INVENTION
Immersed structures include oil and gas rigs, underwater pipelines, columns for rigs, or any kind of offshore structures. It is necessary to inspect these immersed metallic structures in order to access its current structural health to avoid any catastrophic failures and raise alerts for repair or replacement of damaged elements. Determining the structure’s thickness is crucial for analyzing structural deterioration which helps in determining further usable lifespan. Inspection of such structures can be done by non-destructive evaluation (NDE) methods.
Typically submersible ultrasonic thickness measurement units require contact with the target metal surface to obtain measurement, improper contact of probe with surface of structure leads to no measurement. For a ROV to perform such measurements is difficult and highly challenging to make a proper contact with the target material due to environmental conditions like high currents, slippery surface, etc.
Further, the modules are available for signal processing of ultrasonic thickness measurement are primarily for contact type methods. Real-time contactless ultrasonic thickness measurement from a finite stand-off distance from target material lacks data processing modules to obtain real-time, reliable measurements.
Thus there is need for a system and method for real-time contactless ultrasonic thickness measurement of immersed structures to address the aforementioned issues and to ease the UT measurement by using sophisticated module which analyses and processes the data to obtain reliable results.
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. These objectives 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 provide a novel data processing module for real-time contactless thickness measurement of immersed structures.
Further objective of the current invention is to provide a customisable control and scalable module which can support vast range of probes, signal processing unit configurations and environmental conditions like turbidity and murkiness to produce reliable measurement under any working conditions.
Yet another objective of the invention is to reduce the time and effort required for the ultrasonic inspection of structure surface by using ROVs.
These objectives are achieved according to the invention, an ultrasonic thickness measurement system for measuring thickness of immersed structures comprising of an ultrasonic probe encased in a casing capable of withstanding high-pressures. Immersed, ultrasonic probe is not in contact with the structure. The probe is designed to operate in a liquid environment and all connections are leak proof. The probe is connected to a pulser receiver also known as signal processing unit which is integrated to data processing module. The data processing module includes signal filtering, algorithms for signal smoothing, peak detection algorithms, heuristic algorithms for thickness measurement and data selection algorithms for data processing and thickness 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 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 shows real-time contactless ultrasonic thickness measurement system, according to an embodiment of the present invention; and
Figure 2 shows data processing flow in a processing module, 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 shows real-time ultrasonic thickness measurement system, according to an embodiment of the present invention. Accordingly an ultrasonic thickness measurement system 100 for thickness measurement of immersed structures consists of ultrasonic probe 102 encased in a casing 104 capable of withstanding high-pressures. Immersed ultrasonic probe 102 is not in contact with the structure 106. The probe 102 is designed to operate in a liquid environment and all connections are watertight. Immersed probe 102 usually have an impedance matching layer that helps to get more sound energy into the water and, in turn, into the structure being inspected. Further, the focused probe 102 can improve the sensitivity and axial resolution by concentrating sound energy to a smaller area. The probe is capable of transmitting and receiving signals in the proximity of 4mm to 1000mm from the structure 106. The probe 102 is connected to a pulser receiver also known as signal processing unit 110 which is integrated to data processing module 112. The data processing module 112 includes the data processing module includes a signal filtering, a signal smoothing algorithm, a peak detection algorithm, a thickness measurement algorithm and a data selection algorithm for processing and measurement of structure thickness. The present module 112 is flexible to perform contact based measurements without any hardware change. The processed data can be accessed through application programming interface (API).
In a preferred embodiment the data processing module 112 can include signal filtering, algorithms for signal smoothing, a heuristic peak detection algorithm (HPDA), a heuristic thickness measurement algorithm (HTMA) and data selection algorithms for processing data and thickness measurement of immersed structures.
The method for real-time contactless ultrasonic thickness measurement of immersed structures, involves transmitting data 108A through a structure 106 from first subsurface to the opposite surface of said structure, and receiving reflected data 108B from said structure surface. Transmitting of data to and receiving the reflected data from the surface being conducted by operation of a probe 102, triggered by a pulser receiver 110. The data transmitted and received during the process is usually ultrasonic signals. Further, the received data 108B which is reflected from the targeted structure 106 is sent to data processing module 112, where the received reflected data 108B is processed over different steps. Initially data or digital signal from signal processing unit 110 is considered as raw signal data (RSD) 124. This data is passed to thickness measurement API (TM-API) developed to process the RSD 124 to obtain desired metal thickness. TM-API configuration setting is controlled using graphical user interface (GUI) 122 or can be done by API calls.
Based on API configuration settings RSD 124 is processed through noise filter or set of noise filters 126. This filtered signal data (F-SD) is further processed over set of smoothing algorithms 128 to obtain a smooth signal data (S-SD). S-SD is passed through optimized Hilbert transformations 130 to produce Hilbert signal data (H-SD). On H-SD, the heuristic peak detection algorithm (HPDA) 132 is applied to detect peaks. Based on the type of measurement viz. non-contact or contact, the output of HPDA is processed through heuristic thickness measurement algorithm (HTMA) 134 to obtain thickness of the targeted structure 106. The HPDA 132 also calculates the length of water column present between the probe 102 and the structure 106. The thickness values are collected over a particular period and validated using pseudo thickness validation algorithm (PTVA) 136 based on liquid column length between probe 102 and structure surface obtained through HPDA output. The validated thickness and output data at each algorithmic module can be accessed through API 140 and plotted as a graph based on GUI configurations 144. Alternatively, based on API configuration signal data can be acquired 138 and the thickness value can be called using API 142 for displaying on the GUI 144. Processing of the received signal data plays a crucial role in obtaining reliable measurements. The corresponding figure 2 shows data processing flow in a processing module, according to an embodiment of the present invention.
Aforesaid ultrasonic thickness measurement system is suitable for any kind of submersed thickness measurement surveys or inspections of metallic structures in oil and gas industries, shipping industries, marine and offshore industries. The immersion ultrasonic thickness measurement system can be used for ultrasonic A-scan and B-scan inspections with the support of external localization equipment’s.
The measurement system is compact, portable and eases the metal thickness measurement operations for ROVs as compare to similar systems in the same field. And also the system is robust, customisable and has novel scalable data processing module support. Further the invention reduces the probe damage caused due to contact and increases the probe life-time.
Further, the measurement system has customisable control and scalable module which can support vast range of probes, signal processing unit configurations and environmental conditions like turbidity and murkiness to produce reliable measurement under any working conditions. And also reduces the time and effort required for the ultrasonic inspection of structure surface by using ROVs.
While the preferred embodiment of the invention has been illustrated and described herein, it is to be understood that the invention is not limited to the precise construction herein disclosed, and the right is reserved to all changes and modifications coming within the scope of the invention.

I/we claim,
1. A real-time contactless ultrasonic thickness measurement system for immersed structures, comprising: an ultrasonic probe encased in a casing withstanding high-pressure; the probe connected to a pulser receiver integrated to a data processing module, wherein the data processing module includes a signal filtering, a signal smoothing algorithm, a peak detection algorithm, a thickness measurement algorithm and a data selection algorithm which are controlled in an application programming interface (API) for processing and measurement of structure thickness.
2. A real-time contactless ultrasonic thickness measurement system according to claim 1, wherein the probe adapted to be capable of transmitting and receiving signals in the proximity of 4mm to 1000mm from the structure.
3. A real-time contactless ultrasonic thickness measurement system measurement system according to claim 1, wherein the peak detection algorithm is a heuristic peak detection algorithm (HPDA).
4. A real-time contactless ultrasonic thickness measurement system according to claim 1, wherein the thickness measurement algorithm is a heuristic thickness measurement algorithm (HTMA).
5. A real-time contactless ultrasonic thickness measurement system according to claim 1, is capable of measuring water column length between the probe and the structure.
6. A real-time contactless ultrasonic thickness measurement system according to claim 1, wherein the structure is made of metal.
7. A method for real-time contactless ultrasonic thickness measurement of immersed structure, comprising:
transmitting data through a structure from said first subsurface to the opposite surface of said structure, receiving reflected data from said structure surface, the transmitting of data to, and receiving the reflected data from the surface being conducted by operation of a probe triggered by a pulser receiver;
processing received data, wherein processing includes:
transforming data to hilbert data for determining peaks, wherein the peaks are detected by means of heuristic peak detection algorithm (HPDA); and
measuring thickness of the targeted structure by applying heuristic thickness measurement algorithm (HTMA);
validating thickness values collected over a period by means of pseudo thickness validation algorithm (PTVA) and displaying validated thickness on a graphical user interface (GUI).
8. The method for real-time contactless ultrasonic thickness measurement according to claim 7, further includes filtering, and smoothing of data before transforming.
9. The method for real-time contactless ultrasonic thickness measurement, according to claim 8, wherein the validated thickness and output data at each algorithmic module is accessed through an application programming interface (API) and plotted as a graph based on the GUI configurations.

Dated this the 31st day of October, 2017

ABSTRACT
Title: A system and method for real-time ultrasonic thickness measurement of immersed structures
The present invention relates to a system and method for real-time contactless ultrasonic thickness measurement of immersed structures, developed to support inspection by means of submersible ROVs. Accordingly, an ultrasonic thickness measurement system for measuring thickness of immersed structures consisting of ultrasonic probe encased in a casing capable of withstanding high-pressures. Immersed ultrasonic probe is not in contact with the structure. The probe is designed to operate in a liquid environment and all connections are leak proof. Further, the probe is connected to a pulser receiver also known as signal processing unit which is integrated to data processing module. The data processing module includes signal filtering, algorithms for signal smoothing, peak detection algorithms, heuristic algorithms for thickness measurement and data selection algorithms for data processing and thickness measurement of immersed structures.
Figure 1 (for publication)
,CLAIMS:I/we claim,
1. A real-time contactless ultrasonic thickness measurement system for immersed structures, comprising: an ultrasonic probe encased in a casing withstanding high-pressure; the probe connected to a pulser receiver integrated to a data processing module, wherein the data processing module includes a signal filtering, a signal smoothing algorithm, a peak detection algorithm, a thickness measurement algorithm and a data selection algorithm which are controlled in an application programming interface (API) for processing and measurement of structure thickness.
2. A real-time contactless ultrasonic thickness measurement system according to claim 1, wherein the probe adapted to be capable of transmitting and receiving signals in the proximity of 4mm to 1000mm from the structure.
3. A real-time contactless ultrasonic thickness measurement system measurement system according to claim 1, wherein the peak detection algorithm is a heuristic peak detection algorithm (HPDA).
4. A real-time contactless ultrasonic thickness measurement system according to claim 1, wherein the thickness measurement algorithm is a heuristic thickness measurement algorithm (HTMA).
5. A real-time contactless ultrasonic thickness measurement system according to claim 1, is capable of measuring water column length between the probe and the structure.
6. A real-time contactless ultrasonic thickness measurement system according to claim 1, wherein the structure is made of metal.
7. A method for real-time contactless ultrasonic thickness measurement of immersed structure, comprising:
transmitting data through a structure from said first subsurface to the opposite surface of said structure, receiving reflected data from said structure surface, the transmitting of data to, and receiving the reflected data from the surface being conducted by operation of a probe triggered by a pulser receiver;
processing received data, wherein processing includes:
transforming data to hilbert data for determining peaks, wherein the peaks are detected by means of heuristic peak detection algorithm (HPDA); and
measuring thickness of the targeted structure by applying heuristic thickness measurement algorithm (HTMA);
validating thickness values collected over a period by means of pseudo thickness validation algorithm (PTVA) and displaying validated thickness on a graphical user interface (GUI).
8. The method for real-time contactless ultrasonic thickness measurement according to claim 7, further includes filtering, and smoothing of data before transforming.
9. The method for real-time contactless ultrasonic thickness measurement, according to claim 8, wherein the validated thickness and output data at each algorithmic module is accessed through an application programming interface (API) and plotted as a graph based on the GUI configurations.

Dated this the 31st day of October, 2017