Description:FORM 2

THE PATENTS ACT 1970
(Act 39 of 70)
&
The Patent Rules, 2003

COMPLETE SPECIFICATION

(See Section 10 and rule 13)

TITLE OF INVENTION:

SYSTEM AND METHOD FOR DETERMINING A GAUGE LENGTH OF A WAVEGUIDE IN REAL-TIME

APPLICANT:

1. (A) Name: XYMA Analytics Private Limited
(B) Nationality: India
(C) Address: B4-01, 4th Floor, B Block, IITM Research Park,
Kanagam, Tharamani, Chennai,
Tamil Nadu 600113

The following specification particularly describes the invention and the manner in which it is to be performed.

SYSTEM AND METHOD FOR DETERMINING A GAUGE LENGTH OF A WAVEGUIDE IN REAL-TIME

[0001] The present disclosure generally relates to waveguides, and more particularly, relates to a system and method for determining a gauge length of a waveguide in real-time.

BACKGROUND

[0002] Waveguide Ultrasonics is widely used for a range of measurements and sensing applications. The ability of waveguides includes multi-modal nature allowing for measurement of multiple parameters and multi-point measurements on the same waveguide leaving a smaller footprint. The measurement of critical parameters such as temperature, density, viscosity and the fluid level of the surrounding media can be accomplished using several embodiments on the waveguides. One known form of application of waveguide is distributed temperature sensor, in which ultrasonic waveguide is intended to be strung out around the area to be monitored. The waveguide is provided with a number of longitudinally distributed special reflecting means, e.g., notches or bends, which divide it into zones defining corresponding zones of the area whose temperature is to be monitored.

[0003] Ultrasonic pulses launched into one end of the waveguide are partially reflected at each reflecting means to form echo pulses, and the respective time intervals between the receipt of successive echo pulses resulting from a given launched pulse are measured in a counter/timer. Since the propagation speed of the ultrasonic pulses in the waveguide is a function of the temperature of the waveguide, the time interval between two successive echo pulses resulting from a given launched pulse is a measure of the average temperature of the zone defined by the two successive reflecting means which gave rise to those echo pulses. For successive reflection of pulse, measuring a distance between successive notches is crucial, which is otherwise called as Gauge-length. Gauge length is the distance between two notches on the waveguide. It is very difficult to measure a Gauge-length of the waveguide with naked eyes and even with some linear scales the measurement resolution is not accurate. Thus, there is a need for a system and method for automatically determining a gauge length of a waveguide in real-time.

SUMMARY
[0004] In an aspect of the present disclosure, a system for determining a gauge length of a waveguide in real-time is disclosed. The system comprises a base comprising an optical bread board, a linear stage unit mounted on the base comprising a support, a dual linear guide rail fixed on the support between a first end plate and a second end plate, a linear lead screw mounted on the support at an axis “X” between the guide rail and the end plates, a driving unit coupled with the linear lead screw at the second end plate, and a working platform coupled with the linear lead screw.

[0005] The system further comprises a linear encoder unit comprising a linear encoder scale and a head mounted on the guide rail, and the head of the linear encoder scale is attached to the working platform and configured to move on the linear encoder scale and a clamping unit comprising two clamps mounted on the base. The waveguide is fixed between two clamps in the axis parallel to the linear lead screw. A digital microscope is further mounted on the working platform. A lens of the digital microscope is configured to focus on the waveguide fixed with the clamping unit and slide along the axis “X” from the first end plate to the second end plate when the linear lead screw is driven by the driving unit. A computing device is communicably connected with the linear encoder unit and the digital microscope. The computing device comprises at least one processor and at least one memory unit.

[0006] In another aspect of the present disclosure, a method for determining a gauge length of a waveguide in real-time is disclosed. The method comprises driving a linear lead screw of a linear stage unit along an axis, moving a digital microscope mounted on a working platform along the axis from a first end plate to the second end plate of the linear stage unit, enabling a linear encoder unit to start measuring linear distance along a path when the digital microscope moves along the axis, focussing the lens of the digital microscope on the waveguide fixed with a clamping unit, and capturing a plurality of real-time images of the waveguide fixed between the two clamps by the digital microscope. A head of the linear encoder unit moves on a linear encoder scale when the digital microscope moves along the axis.

[0007] The method further comprises receiving the plurality of real-time images of the waveguide for analysis from the digital microscope, monitoring at least one dimension of the waveguide from the plurality of real-time images of the waveguide, storing a first digital value of the linear encoder scale being a linear movement of the head on the linear encoder scale and the working platform when a first drop in the dimension of the waveguide is detected, storing a second digital value of the linear encoder scale when a second drop in the dimension of the waveguide is detected, and determining a gauge length of the waveguide by determining a difference between the second digital value and first digital value and converting the difference into an actual value being a linear distance between the first drop and the second drop in dimension on the waveguide. The gauge length of the waveguide is further displayed on an electronic display unit.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The specification refers to the following appended figures, in which the use of like reference numerals in different figures is intended to illustrate like or analogous components.
[0009] Figure 1 illustrates a schematic of a waveguide in accordance with the present disclosure
[0010] Figure 2 illustrates a schematic of the waveguide having a length (L) with a plurality of holes in accordance with the embodiment of the present disclosure.
[0011] Figure 3 illustrates a schematic of the waveguide (200) in accordance with another embodiment of the present disclosure.
[0012] Figure 4 illustrates a schematic of the waveguide (300) in accordance with yet another embodiment of the present disclosure.
[0013] Figure 5 illustrates a schematic of a system for determining a gauge length of a waveguide in real-time in accordance with an exemplary embodiment of the present disclosure.
[0014] Figure 6 illustrates a schematic of a linear stage unit in accordance with the present disclosure.
[0015] Figure 7 illustrates a flow chart for determining the gauge length of a waveguide in real-time in accordance with another embodiment of the present disclosure.

DETAILED DESCRIPTION
[0016] In the present disclosure, a system, and a method for determining a gauge length of a waveguide in real-time are disclosed. The system determines the gauge length of the waveguide with micron resolution when compared to existing prior arts. To measure at such resolution, a very important step is to set a measuring point. In the system, the measuring point is set based on a determination of change in the dimension of the waveguide. The waveguide may be made of metals, special alloys, and ceramics.

[0017] Referring to Figure 1, illustrated is a schematic of a waveguide (100) in accordance with the present disclosure. The waveguide has a head end (110) and a free end (120). The waveguide (100) comprises a plurality of special notches (130a, 130b) along a length of the waveguide. The gauge length (GL) of the waveguide is a linear distance between two notches as shown in Figure 1. The measuring point (150) on the waveguide for the gauge length (GL) measurement is set at an edge of a notch. In the present embodiment of the present disclosure, the diameter of the notch (100) starts from 0.3 mm. In the present embodiment of the present disclosure, the diameter of the waveguide (100) starts from 1 mm.

[0018] In one embodiment of the present disclosure, a system for determining a gauge length of a waveguide in real-time is disclosed. The system comprises a base and a linear stage unit mounted on the base, wherein the linear stage unit comprises: a) a support, b) a dual linear guide rail fixed on the support between a first end plate and a second end plate, c) a linear lead screw mounted on the support at an axis “X” between the guide rail and the end plates, d) a driving unit coupled with the linear lead screw at the second end plate, and e) a working platform coupled with the linear lead screw. The system further comprises a linear encoder unit mounted on the guide rail, the linear encoder unit comprises a head and a linear encoder scale attached on a side surface of the guide rail. The head of the linear encoder unit is attached to the working platform and moves on the linear encoder scale attached on the guide rail.

[0019] The system further comprises a clamping unit comprising two clamps mounted on the base for fixing the waveguide in the axis parallel to the linear lead screw, and a digital microscope mounted on the working platform. A lens of the digital microscope focuses on the waveguide fixed with the clamping unit and slides along the axis “X” from the first end plate to the second end plate when the linear lead screw is driven by the driving unit and a computing device communicably connected with the linear encoder unit and the digital microscope, wherein the computing device comprises at least one processor and at least one memory unit. The digital microscope captures real-time images of the waveguide fixed between the two clamps.

[0020] Referring to Figure 2, illustrated is a schematic of the waveguide (100) having a length (L) with a plurality of holes in accordance with the embodiment of the present disclosure. The waveguide (100) is configured as a cylindrical rod and the plurality of notches may comprise a plurality of holes on the length (L) of the waveguide. Each hole has a predefined diameter (d). The diameter of the hole ranges from 0.3 mm to 1 mm, on waveguides with a diameter in the range of 1 mm to 20 mm, preferably in the range of 1 mm to 8 mm. The measuring point (150) from a head end (110) on the waveguide for the gauge length (GL) measurement is set at an edge of a hole as shown in Figure 2. The gauge length is the linear distance between the edges of the two holes. Further, a remaining length of the waveguide may also be determined using the system in the present invention. The linear distance between the edge of the hole and the free end (120) of the waveguide is called as remaining length (RL) of the waveguide. The length of the waveguide ranges from 400 mm to 8000 mm. In a preferred embodiment of the present disclosure, the length of the waveguide is 1000 mm.

[0021] Referring to Figure 3, illustrated is a schematic of the waveguide (200) in accordance with another embodiment of the present disclosure. The waveguide (200) is configured as a cylindrical rod and the plurality of notches may comprise a plurality of slots on the length (L) of the waveguide. The measuring point (250) from a head end (210) on the waveguide for the gauge length (GL) measurement is set at an edge of a slot as shown in Figure 3. The Edge of the slot is determined when a change or drop in diameter of the rod is determined from a head end (210), and the measuring point (250) for the gauge length (GL) measurement is set. The gauge length is the linear distance between the edges of the two slots. Further, the remaining length of the waveguide may also be determined using the system/method in the present invention. The linear distance between the edge of the slot and the free end (220) of the waveguide is called as remaining length (RL) of the waveguide.

[0022] Referring to Figure 4, illustrated is a schematic of the waveguide (300) in accordance with yet another embodiment of the present disclosure. The waveguide (300) is configured as a rectangular rod and the plurality of notches may comprise a plurality of slots on the length (L) of the waveguide. The rectangular rod may have a flat section. As similar to the previous embodiment, the gauge length (GL) and remaining length (RL) of the waveguide are determined using the system/method in the present invention. The measuring point (350) from a head end (310) on the waveguide for the gauge length (GL) measurement is set at an edge of a slot as shown in Figure 4. The Edge of the slot is determined when a change/drop in thickness of the rod is determined from a head end (310).

[0023] In embodiments of the present disclosure, the waveguide is made in multiple configurations selected from a cylindrical rod, a rectangular rod /bar, a strip, and a wire. As disclosed in the previous embodiment, the length of the rod-type waveguide is preferably in the range of 400 mm to 8000 mm. The strip type may have a thickness ranging from 0.3 mm to 1 mm, a length ranging from 20 mm to 1000 mm, and a width ranging from 5 mm to 10 mm. The waveguide is made of a material selected from ceramic, metal, and metal alloys. In the embodiment of the present disclosure, the metal is selected from, not only limited to steel, aluminium, steel alloy, super alloys or a combination thereof.

[0024] Referring to Figure 5, illustrated is a schematic of a system for determining the gauge length of a waveguide in real-time in accordance with an exemplary embodiment of the present disclosure. The system (500) comprises a base (510) comprising an optical breadboard, a linear stage unit (520) mounted on the base (510), a linear encoder scale (550) mounted on the linear stage unit (520), a clamping unit (560) mounted on the base (510), a digital microscope (570) mounted on the linear stage unit (520) and a computing device (580) communicably connected with the linear encoder unit and the digital microscope (570). The waveguide (100) may comprise a plurality of notches (130a, 130b) along a length of the waveguide as shown in Figures 1-2. The waveguides as shown in Figures 3-4 may also be used in the exemplary embodiment of the present disclosure.

[0025] Referring to Figure 6, illustrated is a schematic of the linear stage unit in accordance with the present disclosure. The linear stage unit (520) comprises a support (525) and a dual linear guide rail (530) fixed on the support (525) between a first end plate (522) and a second end plate (524). The linear stage unit (520) further comprises a linear lead screw (534) mounted on the support at an axis “X” between the guide rail (530) and the end plates (522, 524), a driving unit (536) coupled with the linear lead screw at the second end plate, and a working platform (537) coupled with the linear lead screw (534).

[0026] The linear encoder scale unit (550) is mounted on the guide rail (530) of the stage unit. The linear encoder unit (550) comprises a head and a linear encoder scale (552). The linear encoder scale is a magnetic tape (552), attached to a side surface of the guide rail (530).The head of the linear encoder scale (550) is attached to the working platform (537) and configured to move/slide on the magnetic tape (532) along the axis “X”. The clamping unit (560) comprises two clamps (562, 564) mounted on the base (510). The waveguide (100) is clamped between two clamps (562, 564) in the clamping unit in the axis parallel to the linear lead screw (534).

[0027] In one embodiment of the present disclosure, the driving unit may comprise a rotating knob used for manually driving or rotating the linear lead screw of the linear stage unit. In another embodiment of the present disclosure, the driving unit may comprise a motor driven by a power supply. The motor may be a stepper motor actuated or driven based on a requirement of rotation of the linear lead screw.

[0028] The digital microscope (570) is mounted on the working platform (537) of the linear stage unit (520). A lens of the digital microscope is configured to focus on the waveguide fixed with the clamping unit (560) and slide along the axis “X” from the first end plate (522) to the second end plate (524) when the linear lead screw (534) is driven by the driving unit (536). The computing device (580) may be connected with the linear encoder unit and the digital microscope (570) through a wired/wireless medium. The computing device (580) comprises at least one processor and at least one memory unit. In one embodiment, the computing device comprises an electronic display unit for displaying the gauge length of the waveguide.

[0029] In another embodiment, a separate display unit is mounted on the base (510) and connected with the linear encoder unit and the digital microscope (570) through a wired/wireless medium. The separate display unit may comprise a digital display unit (590) used for displaying a linear distance and the gauge length of the waveguide. The separate display unit displays the digital values of the linear movement/distance of the head on the linear encoder scale and the working platform. The separate display unit displays the first digital value when a first drop in the dimension of the waveguide is detected. The first digital value may be noted down by a user or stored automatically in a memory of a computing device. Further, the separate display unit may be reset to show a second digital value when a second drop in the dimension of the waveguide is detected. The second digital value may also be noted down by a user or stored automatically in the memory of the computing device.

[0030] In the present embodiments of the disclosure, the gauge length of the waveguide is automatically determined by using the system. The determination/ measurement of the gauge length of the waveguide is based on a linear encoder unit. The linear encoder scale uses a reader head for analysing displacement. The linear motion of the reader is achieved by a 200mm linear screw translation stage and the reader’s head is connected to the linear stage in such a way the measurement is independent of backlash in the linear stage screw. The clamping is crucial, in some cases the waveguide won’t be straight. To overcome this constraint the clamping mechanism is enabled with a straightening mechanism in the measuring region.

[0031] The system of the present invention is able to measure gauge length with micron resolution. It is very difficult to set up starting and ending points with naked eyes since the resolution is in microns, setting up a measuring point is very important. The microscope and the computing device of the system aid in setting up measuring points for gauge length resolving 1-micron resolution. The initial step of the measurement is placing/fixing the waveguide in the clamping unit. After the waveguide is fixed, the liner stage screw may start measuring linear distance when the linear lead screw is rotated by the driving unit along the axis. The focus of the starting point can be done with a linear stage screw and the microscope, in horizontal and vertical directions respectively. Once the microscope is focused on the start point, the distance to the endpoint is measured by the linear movement of the stage. The distance measured by the encoder is processed and visualized by the digital display unit. The digital display unit displays the measurement in millimetres with a resolution of 1 micron. The maximum distance/gauge length of the waveguide that can be measured using the system is 150mm.

[0032] In an example of the present invention, a motor coupled with a driving unit drives the linear lead screw of the linear stage unit along an axis. Due to the rotation of the linear lead screw, the digital microscope moves or slides along the axis from the first end plate to the second end plate of the linear stage unit. The linear encoder unit is triggered to start measuring a linear distance along a path when the digital microscope slides along the axis. The head of the linear encoder unit moves on the linear encoder magnetic scale and a digital value for each movement of a head may be stored in a computing device.

[0033] The digital microscope focuses and captures a plurality of real-time images of the waveguide fixed between the two clamps and sends the captured images to the computing device. The plurality of real-time images may be analysed by the computing device connected with the digital microscope for determining the gauge length of the waveguide. The computing device analyses the plurality of real-time images and monitors a dimension of the waveguide from the plurality of real-time images of the waveguide. For example, the diameter of the waveguide in the images is monitored by the computing device. The computing device particularly, monitors dimension of the waveguide for detecting an edge of the notch on the waveguide. A change/drop in the dimension of the waveguide is determined for detecting the edge of the notch on the waveguide.

[0034] The head of linear encoder unit continues to move on the linear encoder magnetic scale when the digital microscope captures a plurality of real-time images and the computing device analyses the plurality of real-time images. Thus, the movement of the head, images capturing and analysis happen simultaneously at real-time. The images are analysed for detecting an edge of the notch on the waveguide. A first digital value of the linear encoder scale is marked or noted when an edge of a first notch is detected through a first drop in the dimension of the waveguide. The first digital value of the linear encoder scale is a linear distance of the head moved on the linear encoder scale.

[0035] In other words, the first digital value of the linear encoder scale is stored in the computing device, when a first drop in the dimension of the waveguide is detected. Similarly, an edge of a second notch of the waveguide is detected through a second drop in the dimension of the waveguide and a second digital value of the linear encoder scale is stored in the computing device.

[0036] In another embodiment of the present disclosure, a method for automatically determining a gauge length of a waveguide in real-time is disclosed. The method comprises rotating a linear lead screw of a linear stage unit along an axis by a driving unit either manually or automatically, moving a digital microscope along the axis from a first end plate to the second a plate of the linear stage unit, enabling a linear encoder unit to start measuring linear distance along a path when the digital microscope moves along the axis, focussing the lens of the digital microscope on the waveguide fixed with a clamping unit, and capturing a plurality of real-time images of the waveguide fixed between the two clamps.

[0037] The method further comprises receiving the plurality of real-time images of the waveguide for analysis from the digital microscope, monitoring at least one dimension of the waveguide from the plurality of real-time images of the waveguide, and storing a first digital value of the linear encoder scale storing a first digital value of the linear encoder scale being a linear movement of the head on the linear encoder scale and the working platform when a first drop in the dimension of the waveguide is detected, storing a second digital value of the linear encoder scale when a second drop in the dimension of the waveguide is detected, determining a gauge length of the waveguide by determining a difference between the second digital value and first digital value and converting the difference into an actual value being a distance between the first drop and the second drop in dimension, and displaying the gauge length of the waveguide on an electronic display unit. Referring to Figure 7, illustrated is a flow chart for determining the gauge length of a waveguide in real-time in accordance with another embodiment of the present disclosure.

[0038] In the embodiment of the present disclosure, the method is implemented by the system of the present invention. The drop in the dimension of the waveguide is determined for detecting a notch on the waveguide. The drop in dimension of the waveguide comprises a decrease in diameter of the waveguide. In some other embodiments, the drop in dimension of the waveguide comprises a drop in thickness of the waveguide. Alternatively, the drop in dimension of the waveguide comprises a drop in length or width of the waveguide.

[0039] In an alternate embodiment of the present disclosure, the method comprises simultaneously analysing the plurality of real-time images of the waveguide fixed between the two clamps for determining a drop in dimension of the waveguide and storing digital values of the linear encoder scale to measure a linear distance between the first drop and the second drop in the dimension of the waveguide being a gauge length of the waveguide. The waveguide gauge length measurement is critical for the accuracy of our sensors. In the present invention, the gauge length of the waveguide is determined either automatically or by manually using a driving unit rotated by a user.

[0040] The waveguide measurements are required in high & low temperature sensor(μTMapS), Level measurement sensor (Ztar), Viscosity and temperature (PoRTS) sensor.
, Claims:CLAIMS
We claim:

1. A system (500) for determining a gauge length of a waveguide (100) in real-time, the system (500) comprising:
a base (510) comprising an optical breadboard;
a linear stage unit (520) mounted on the base (510), wherein the linear stage unit (520) comprises:
a) a support (525),
b) a dual linear guide rail (530) fixed on the support (525) between a first end plate (522) and a second end plate (524).,
c) a linear lead screw (534) mounted on the support at an axis “X” between the guide rail (130) and the end plates (522, 524),
d) a driving unit (536) coupled with the linear lead screw at the rear end plate, and
e) a working platform (537) coupled with the linear lead screw (534);
a linear encoder unit (550) comprising a linear encoder scale (552) and a head, mounted on the guide rail (530), wherein the linear encoder scale (552) is attached on a side surface of the guide rail (525) and the head of the linear encoder (550) is attached to the working platform (537) and configured to move on the linear encoder scale (552);
a clamping unit (560) comprising two clamps (562, 564) mounted on the base (510), wherein the waveguide (100) is fixed between two clamps (562, 564) in the axis parallel to the linear lead screw (534), and
a digital microscope (570) mounted on the working platform (537), wherein a lens of the digital microscope is configured to focus on the waveguide fixed with the clamping unit (560) and slide along the axis “X” from the first end plate (522) to the second end plate (524) when the linear lead screw (534) is driven by the driving unit (536); and
a computing device (580) communicably connected with the linear encoder unit (550) and the digital microscope (570), wherein the computing device (580) comprises at least one processor and at least one memory unit.

2. The system as claimed in claim 1, wherein the system comprises an electronic display unit (590) for displaying the gauge length of the waveguide.

3. The system as claimed in claim 1, wherein the waveguide (100) is made in a configuration selected from a rod, a strip, and a wire.

4. The system as claimed in claim 1, wherein the waveguide (100) is made of a material selected from a ceramic, a metal, and metal alloys.

5. The system as claimed in claim 4, wherein the metal comprises at least one of steel, aluminium, steel alloy, and superalloys.

6. The system as claimed in claim 1, wherein the waveguide (100) comprises a plurality of holes (130a, 130b) along a length of the waveguide.

7. The system as claimed in claim 1, wherein the waveguide (100) comprises a plurality of slots along a length of the waveguide.

8. A method for determining a gauge length of a waveguide in real-time, the method comprising:
driving a linear lead screw of a linear stage unit along an axis by rotating a driving unit;
moving a digital microscope mounted on a working platform along the axis from a first end plate to a second plate of the linear stage unit;
enabling a linear encoder unit to start measuring a linear distance along a path when the digital microscope slides along the axis, wherein a head of the linear encoder unit moves on a linear encoder scale when the digital microscope moves along the axis;
focussing the lens of the digital microscope on the waveguide fixed between two clamps of a clamping unit;
capturing a plurality of real-time images of the waveguide fixed between the two clamps by the digital microscope;
receiving the plurality of real-time images of the waveguide for analysis from the digital microscope;
monitoring at least one dimension of the waveguide from the plurality of real-time images of the waveguide;
storing a first digital value of the linear encoder unit being a linear movement of the head on the linear encoder scale, when a first drop in the dimension of the waveguide is detected;
storing a second digital value of the linear encoder unit when a second drop in the dimension of the waveguide is detected;
determining a gauge length of the waveguide by determining a difference between the second digital value and first digital value and converting the difference into an actual value being a linear distance between the first drop and the second drop in dimension; and
displaying the gauge length of the waveguide on an electronic display unit.

9. The method as claimed in claim 8, wherein a drop in the dimension of the waveguide is determined for detecting an edge of a notch on the waveguide.

10. The method as claimed in claim 8, wherein the drop in dimension of the waveguide comprises a decrease in at least one of diameter, length, and thickness of the waveguide.

11. The method as claimed in claim 8, wherein the waveguide is fixed between two clamps of the clamp unit in an axis parallel to the linear lead screw.

12. The method as claimed in claim 8, wherein the method comprises:
simultaneously analysing the plurality of real-time images of the waveguide fixed between the two clamps for determining a change or drop in dimension of the waveguide; and
storing digital values of the linear encoder scale to measure a linear distance between the first drop and the second drop in the dimension of the waveguide being a gauge length of the waveguide.

13. The method as claimed in claim 8, wherein the method comprises automatically determining the gauge length of a waveguide in real-time.