Waveguide for position measurement magnetic sensor for propagation velocity compensation

Abstract

A waveguide for a position measurement magnetic sensor for propagation velocity compensation is disclosed. Waveguide sensors and position sensing systems are provided. In some embodiments, a position sensing system can include a waveguide configured to receive and transmit a pulse and a magnet movable relative to the waveguide. The waveguide can include a first core layer and a second core layer; a magnetic layer between the first core layer and the second core layer; and a conductive winding around the first core layer, the second core layer, and the magnetic layer. The position sensing system can also include a first substrate layer above the conductive winding and a second substrate layer below the conductive winding.

Description

Technical Field

[0001] Embodiments of this disclosure generally relate to waveguide-based position sensors, and more specifically, to pulsed waveguides comprising PCB-based stacks. Background Technology

[0002] Figure 1 illustrates a conventional position measurement system 100. System 1 includes a sensor 10, a pulse generator 20, and a signal receiver 24. Sensor 10 includes a waveguide 12 and a magnet 14. Typically, magnet 14 is attached to a movable object. During operation, pulse generator 20 generates a pulse 21 that is transmitted to waveguide 12. Magnet 14 creates an impedance discontinuity 11 in a region of waveguide 12 near magnet 14. Reflection of pulse 21 occurs at the point of impedance discontinuity 11, resulting in a reflected pulse 23. Signal receiver 24 receives pulse 21 and reflected pulse 23. The position of magnet 14 relative to waveguide 12 can be determined based on the timing of pulse 21 relative to reflected pulse 23. More specifically, the difference between the time of receiving pulse 21 and the time of receiving reflected pulse 23 can be used to determine the position of magnet 14.

[0003] However, current methods for manufacturing pulsed waveguides require complex processes, leading to high capital investment, stringent manufacturing process control, and direct labor involvement. As a result, consistency in quality is often compromised.

[0004] This disclosure is made in connection with the above content. Summary of the Invention

[0005] In some embodiments, a position sensing system may include: a waveguide configured to receive and transmit pulses and a magnet movable relative to the waveguide. The waveguide may include: a first core layer and a second core layer; a magnetic layer between the first core layer and the second core layer; and a conductive winding surrounding the first core layer, the second core layer, and the magnetic layer. The position sensing system may also include a first substrate layer above the winding and a second substrate layer below the winding.

[0006] In some embodiments, a position sensing system may include: a waveguide configured to receive and transmit pulses, the waveguide being configured as a stacked layer; and a magnet movable relative to the waveguide. The stacked layer of the waveguide may include: a first core layer and a second core layer; a magnetic layer between the first core layer and the second core layer; and a conductive winding surrounding the first core layer, the second core layer, and the magnetic layer. The position sensing system may further include a first substrate layer above the winding and a second substrate layer below the winding.

[0007] In some embodiments, a waveguide for receiving and transmitting pulses may include: a first core layer and a second core layer; and a magnetic layer between the first core layer and the second core layer, the magnetic layer being embedded within an insulating material. The waveguide may also include conductive windings surrounding the first core layer, the second core layer, and the magnetic layer; and a first substrate layer above the windings and a second substrate layer below the windings. Attached Figure Description

[0008] The accompanying drawings illustrate exemplary methods of this disclosure, including practical applications of its principles, and in the drawings:

[0009] Figure 1 shows a block diagram of a prior art positioning sensing system;

[0010] Figure 2 This is a block diagram illustrating a position sensing system according to an embodiment of the present disclosure;

[0011] Figure 3 A more detailed illustration is shown according to embodiments of the present disclosure. Figure 2 A block diagram of a portion of a position sensing system;

[0012] Figures 4A-4C This is a top view of the waveguide of a position sensing system according to an embodiment of the present disclosure;

[0013] Figure 5 It is according to the embodiments of this disclosure along Figure 4A The side cross-sectional view of the waveguide stacked layers taken by the cutting line 5-5;

[0014] Figure 6 An unfolded view of a selected layer of a waveguide according to an embodiment of the present disclosure is shown;

[0015] Figures 7A-7C Various waveguide configurations according to embodiments of the present disclosure are shown.

[0016] The accompanying drawings are not necessarily to scale. The drawings are merely illustrative and not intended to depict specific parameters of this disclosure. The drawings are intended to depict typical embodiments of this disclosure and should therefore not be considered as limiting in scope. In the drawings, similar numbers represent similar elements.

[0017] Furthermore, for clarity, certain elements in some figures may be omitted or not shown to scale. For clarity, cross-sectional views may be in the form of "slices" or "near-view" cross-sections, omitting certain background lines that would otherwise be visible in a "true" cross-sectional view. Additionally, for clarity, some reference numerals may be omitted in certain figures. Detailed Implementation

[0018] The position sensing system and waveguide according to this disclosure will now be described more fully below with reference to the accompanying drawings, in which embodiments of the position sensing system and waveguide are illustrated. However, the position sensing system and waveguide may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the systems and methods to those skilled in the art.

[0019] This disclosure describes several example embodiments of position system sensors including PCB-based pulsed waveguide (PWG) propagation velocity compensation. Typically, these examples are PWG position sensors comprising a waveguide and a magnet. In some embodiments, this disclosure provides compensation by measuring both one end of the reflected pulse and the traveling pulse. Note that the example sensors detailed herein can be implemented in a variety of different systems, such as level systems, gearboxes, welding machines, robotic systems, etc. However, the examples are not limited to these aspects. Additionally, this disclosure can be implemented to compensate for changes in propagation velocity due to temperature, external magnetic fields, manufacturing tolerances, changes in waveguide characteristic response due to waveguide aging, etc. However, this is not intended to be limiting.

[0020] Figure 2 A block diagram of a position sensing system 200 arranged according to at least some embodiments of the present disclosure is shown. System 200 includes a position sensor 210 (sometimes referred to herein as a “sensor”), which includes a waveguide 212 and a magnet 214. In some embodiments, the waveguide 212 is a PWG (Polymer Gauge Frame). In other embodiments, the waveguide 212 may be, for example, a microstrip waveguide, a stripline waveguide, a rectangular waveguide, etc. Additionally, the magnet 214 may be any of various types of magnets (e.g., a permanent magnet, an electromagnet, etc.). The magnet 214 is movable relative to the waveguide 212. Typically, the magnet 214 creates a point of impedance discontinuity 211 in the waveguide 212. The impedance discontinuity 211 is created at the position of the magnet 214 relative to the waveguide 212. The position of the waveguide 212 relative to the magnet 214 may be determined based on one end of an initial pulse (e.g., 221), a reflected pulse (e.g., 223), and a traveling pulse (e.g., 225). Specifically, the location can be determined without considering the wave propagation speed within waveguide 212.

[0021] In practice, magnet 214 or waveguide 212 can be attached to a movable object whose position is to be determined. For example, in some embodiments, magnet 214 can be fixed to a movable object (e.g., a sewing head, laser, welding nozzle, liquid float, etc.). Waveguide 212 can be fixed to a cooperative structure that can be positioned along the path of the movable object. As another example, in some embodiments, waveguide 212 can be fixed to the movable object, while magnet 214 is fixed to the cooperative structure. Accordingly, during operation, as the movable object moves, its position relative to the cooperative structure can be determined based on determining the position of waveguide 212 relative to magnet 214.

[0022] To determine the position of waveguide 212 relative to magnet 214, system 200 may include compensator 202 having pulse generator 220 and position determination module 230. Pulse generator 220 and position determination module 230 are operatively connected to waveguide 212 (e.g., via electrical connection, etc.). Pulse generator 220 may be configured to generate signal pulses (e.g., pulse 221), wherein pulse 221 is transmitted to waveguide 212 and reflected at a point of impedance discontinuity 211, resulting in reflected pulse 223. Additionally, pulse 221 is transmitted through the waveguide and exits waveguide 212 as one end of traveling pulse 225. Compensator 202 is configured to determine the position of waveguide 212 relative to magnet 214 based on pulse 221, reflected pulse 223, and said end of traveling pulse 225. In some examples, the compensator 202 may be configured to determine the position of the waveguide 212 relative to the magnet 214 based at least in part on controlling the timing of the pulse 221 (e.g., by controlling the period for a series of pulses 221). In some examples, the compensator 202 may be configured to determine the position of the waveguide 212 relative to the magnet 214 at least in part by comparing the time between the pulse 221 and one end of the traveling pulse 225 with the reflected pulse 223.

[0023] In some examples, system 200 can be configured to determine the position of waveguide 212 relative to magnet 214 in part by controlling the timing of pulses 221. For example, the period between pulses 221 can be controlled to compensate for the temperature dependence of the time between the pulse 221 delivered to waveguide 212 and the reflected pulse 223 leaving waveguide 212.

[0024] Figure 3 A block diagram of an example implementation of the compensator 302 is shown. While not limiting, the compensator 302 can be implemented as follows: Figure 2The compensator 202 in system 200. The compensator 302 may include a pulse generator 320 and a position determination module 330. As shown, the pulse generator 320 is operatively connected to one end of the waveguide 212 to both transmit pulse 221 to the waveguide and receive a horizontal pulse 225 from the waveguide 212. Additionally, the position determination module 330 is operatively connected to both the pulse generator 320 and the waveguide 212 to receive pulse 221 and reflected pulse 223.

[0025] The pulse generator 320 can be configured to generate a series of pulses 221, wherein the period (e.g., the time between pulses 221) corresponds to the time between one end of pulse 221 and line pulse 225. As will be understood, this period can be varied during operation and can be dynamically updated by the pulse generator 320. Accordingly, the time and the corresponding period will change with changes in temperature and / or the wave speed propagating through waveguide 212 (e.g., due to temperature, etc.).

[0026] Figures 4A-4C A waveguide 412 according to an embodiment of the present disclosure is shown. Waveguide 412 may be as described herein and... Figure 2 A portion of the position sensor 210 shown in the figure, wherein waveguide 412 can be configured as a PCB layer stack. Figure 4A The exterior of waveguide 412 is shown, including substrate layer 414 (e.g., PCB layer). Figure 4B-4C A waveguide 412 with substrate layer 414 removed is shown to better observe the conductive winding 415 (e.g., copper) surrounding magnetic layer 418. While not limiting, magnetic layer 418 could be present at the first and second ends 420, 422 of waveguide 412. Figure 4A Ferrite strips extending between the magnetic layers 418. In some embodiments, more than one magnetic layer 418 may be present. Multiple traces 426 are aligned along the outer edge of the conductive winding 415.

[0027] While not limiting, substrate 414 may be made of epoxy resin or polyimide resin. In some cases, the resin may be reinforced with glass fabric or other matrices such as chopped fibers. Substrate 414 may alternately be composed of ceramic or rigid polymer. This list of acceptable substrate materials is not exhaustive, and other materials may also be successfully used. Materials and manufacturing techniques used to form substrates (such as PCBs) are well known to those skilled in the art.

[0028] Now go to Figure 5-6The waveguide 412 will be described in more detail below. As shown, the waveguide 412 can be arranged as a stack of interconnected / coupled layers (e.g., L1-L6). In some embodiments, the waveguide 412 can be surrounded by a first substrate layer 414A and a second substrate layer 414B, wherein the first substrate layer 414A is disposed on top of the first plating layer (L1) 431. In some embodiments, the first plating layer 431 can be a reference plane made of copper. As noted above, the first and second substrate layers 414A, 414B can be made of PCB-type material.

[0029] As further shown, waveguide 412 may include a first core layer 441 and a second core layer 442 surrounding magnetic layer 418. In some embodiments, the first and second core layers 441, 442 are made of FR-4 copper foil laminate. It will be understood that although only two core layers are shown, more than two core layers are possible in other embodiments. Conductive windings 415 (L2 and L5) may be disposed around the first core layer 441, the second core layer 442, and magnetic layer 418. In some embodiments, waveguide 412 may include an insulating layer 432, wherein magnetic layer 418 is embedded within or otherwise surrounded by insulating layer 432. While not limiting, insulating layer 432 may be epoxy resin, such as reinforcing fabric pre-impregnated with epoxy resin. As further shown, waveguide 412 may include a second magnetic layer 419 between the first core layer 441 and the first substrate layer 414A, wherein the second magnetic layer 419 is embedded in or otherwise surrounded by a second insulating layer 433 (e.g., epoxy resin). The second insulating layer 433 may be located below the first plating layer 431.

[0030] As further shown, a second plating layer 444 (L6) may be disposed above the second substrate layer 414B, a third plating layer 445 (L3) may be disposed above the insulating layer 432, and a fourth plating layer 446 (L4) may be disposed above the second core layer 442. While not limiting, the second plating layer 444 may be a reference plane including a copper layer 449. In some embodiments, the fourth plating layer 446 includes a ground connection 453 for the waveguide 412. A third insulating layer (e.g., epoxy resin) 447 may be disposed between the winding 415 and the second plating layer 444.

[0031] The PCB-based stacked design of the waveguide 412 allows for a variety of configurations. For example, such as... Figure 7AAs shown in the top view, waveguide 412 may be configured with one or more bell-shaped portions. More specifically, waveguide 412 may include a first bell-shaped portion 461 at a first end 420 and a second bell-shaped portion 462 at a second end 422. Between the first and second bell-shaped portions 461, 462 is a relatively narrow central portion 463. The first and second bell-shaped portions 461, 462 represent delay regions at the beginning and end of the sensing process as the magnet 417 moves relative to waveguide 412 (e.g., from the first end 420 toward the second end 422). While not limiting, the dimensions of the first and second bell-shaped portions 461, 462 may be the same or different.

[0032] In other embodiments, such as Figure 7B As shown in the side perspective view, waveguide 412 can be configured to be semi-circular or horseshoe-shaped. More specifically, waveguide 412 may include a first end 420 facing the second end 422 and separated from each other by a gap 466. The intermediate portion 463 between the first and second ends 420, 422 may be curved or annular. Each of the first and second ends 420, 422 may represent a “dead zone” during sensing as the magnet 417 moves relative to waveguide 412 (e.g., from the first end 420 toward the second end 422). Figure 7C In some embodiments, waveguide 412 may be configured to include one or more raised and recessed segments between the first end 420 and the second end 422. It will be understood that a wide variety of shapes and configurations are possible within the scope of this disclosure.

[0033] The foregoing discussion is for illustrative and descriptive purposes and is not intended to limit this disclosure to the one or more forms disclosed herein. For example, various features of this disclosure may be combined in one or more aspects, embodiments, or configurations for the purpose of simplifying this disclosure. However, it should be understood that various features of certain aspects, embodiments, or configurations of this disclosure may be combined in alternative aspects, embodiments, or configurations. Furthermore, the following claims are hereby incorporated by reference into this detailed description, wherein each claim itself is a separate embodiment of this disclosure.

[0034] As used herein, elements or steps described in the singular and beginning with the word "a" or "an" should be understood to not exclude plural elements or steps unless such exclusion is explicitly stated. Furthermore, references to "one embodiment" in this disclosure are not intended to exclude the existence of additional embodiments that also incorporate the described features.

[0035] In this document, the terms “including,” “comprising,” or “having,” and their variations, are used to mean encompassing the items listed thereafter, their equivalents, and additional items. Therefore, the terms “including,” “comprising,” or “having,” and their variations, are open-ended expressions and may be used interchangeably throughout this document.

[0036] The phrases “at least one,” “one or more,” and “and / or” used in this article are open-ended expressions that function as both conjunctions and antonymous conjunctions. For example, each of the expressions “at least one of A, B, and C,” “at least one of A, B, or C,” “one or more of A, B, and C,” “one or more of A, B, or C,” and “A, B, and / or C” refers to A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B, and C together.

[0037] All directional references (e.g., proximal, distal, upper, lower, upward, downward, left, right, lateral, longitudinal, front, rear, top, bottom, above, below, vertical, horizontal, radial, axial, clockwise, and counterclockwise) are used for identification purposes only to assist the reader in understanding this disclosure and are not intended to be limiting, particularly regarding location, orientation, or the purpose of this disclosure. Unless otherwise stated, connection references (e.g., attachment, coupling, connection, and engagement) should be interpreted broadly and may include intermediate members between sets of elements and relative movement between elements. Thus, a connection reference does not necessarily imply that two elements are directly connected and fixed to each other.

[0038] Furthermore, reference numerals (e.g., primary, secondary, first, second, third, fourth, etc.) are not intended to suggest importance or priority, but rather to distinguish one feature from another. The accompanying drawings are for illustrative purposes only, and the dimensions, positions, orders, and relative sizes reflected in the drawings may vary.

[0039] Furthermore, the terms "substantial" or "substantially" and "approximately" may be used interchangeably in some embodiments and may be described using any relative measure acceptable to those skilled in the art. For example, these terms may be used as comparisons with reference parameters to indicate deviations from the intended functionality. While not limiting, deviations from reference parameters may be, for example, in amounts less than 1%, less than 3%, less than 5%, less than 10%, less than 15%, less than 20%, etc.

[0040] The scope of this disclosure is not limited to the specific embodiments described herein. In fact, various other embodiments and modifications of this disclosure, besides those described herein, will be apparent to those skilled in the art from the foregoing description and drawings. Therefore, such other embodiments and modifications are intended to fall within the scope of this disclosure. Furthermore, this disclosure has been described herein in the context of specific implementations in specific environments for specific purposes. Those skilled in the art will recognize that its usefulness is not limited thereto, and that this disclosure can be advantageously practiced in any number of environments for any number of purposes. Therefore, the claims set forth below are to be interpreted in accordance with the full scope and spirit of this disclosure as described herein.

Claims

1. A position sensing system, comprising: A waveguide, configured to receive and transmit pulses; and A magnet that is movable relative to the waveguide, wherein the waveguide comprises: First core layer and second core layer; The magnetic layer between the first core layer and the second core layer; Conductive windings surrounding the first core layer, the second core layer, and the magnetic layer; The first substrate layer above the winding and the second substrate layer below the winding; and A first plating layer above the first core layer, wherein the first substrate layer is formed directly on top of the first plating layer, wherein the first plating layer is a reference plane made of a conductive material, and wherein the first core layer and the second core layer are made of FR-4 copper foil laminate.

2. The position sensing system according to claim 1, wherein, The waveguide also includes an epoxy resin layer, and the magnetic layer is embedded within the epoxy resin layer.

3. The position sensing system according to claim 2, wherein, The waveguide also includes: A second magnetic layer is located between the first core layer and the first substrate layer, wherein the second magnetic layer is embedded within a second epoxy resin layer; and The second plating layer above the second substrate layer.

4. The position sensing system according to claim 3, wherein, The waveguide also includes a ground layer between the second core layer and the magnetic layer.

5. The position sensing system according to claim 3, wherein, The waveguide also includes a third epoxy resin layer between the winding and the second coating.

6. The position sensing system according to claim 1, wherein, Both the first substrate and the second substrate layer are printed circuit boards.

7. The position sensing system according to claim 1, wherein, The waveguides are arranged in a semi-circular or wavy shape.

8. The position sensing system according to claim 1, wherein, The waveguide is configured with one or more bell-shaped portions.

9. A position sensing system, comprising: A waveguide configured to receive and transmit pulses, the waveguide being configured as a stacked layer; and A magnet, which is movable relative to the waveguide, wherein the stacked layers of the waveguide comprise: First core layer and second core layer; The magnetic layer between the first core layer and the second core layer; Conductive windings surrounding the first core layer, the second core layer, and the magnetic layer; The first substrate layer above the conductive winding and the second substrate layer below the conductive winding; and A second magnetic layer between the first core layer and the first substrate layer.

10. The position sensing system according to claim 9, wherein, The stacked layers also include an epoxy resin layer, and the magnetic layer is embedded within the epoxy resin layer.

11. The position sensing system according to claim 10, wherein, The stacked layer further includes: A second magnetic layer between the first core layer and the first substrate layer, wherein the second magnetic layer is embedded within a second epoxy resin layer, wherein the epoxy resin layer and the second epoxy resin layer are made of a reinforcing fabric pre-impregnated with epoxy resin. The first coating layer above the second epoxy resin layer; and The second plating layer above the second substrate layer.

12. The position sensing system according to claim 11, wherein, The stacked layer also includes a ground layer between the second core layer and the magnetic layer.

13. The position sensing system according to claim 11, wherein, The stacked layer also includes a third epoxy resin layer between the conductive winding and the second plating layer.

14. The position sensing system according to claim 9, wherein, Both the first substrate layer and the second substrate layer are printed circuit boards.

15. The position sensing system according to claim 9, wherein, The first core layer and the second core layer are made of FR-4 copper foil laminate.

16. A waveguide for receiving and transmitting pulses, the waveguide comprising: First core layer and second core layer; A magnetic layer between the first core layer and the second core layer, the magnetic layer being embedded within a first insulating material; Conductive windings surrounding the first core layer, the second core layer, and the magnetic layer; The first substrate layer above the conductive winding and the second substrate layer below the conductive winding; as well as A first plating layer above the first core layer, wherein the first substrate layer is formed directly on top of the first plating layer, wherein the first plating layer is a reference plane made of a conductive material, and wherein the first core layer and the second core layer are made of FR-4 copper foil laminate.

17. The waveguide according to claim 16, further comprising: A second magnetic layer between the first core layer and the first substrate layer, wherein the second magnetic layer is embedded within a second insulating material, wherein the first insulating material and the second insulating material are reinforcing fabrics pre-impregnated with epoxy resin; and The second plating layer above the second substrate layer.

18. The waveguide of claim 17 further includes a ground layer between the second core layer and the magnetic layer.

19. The waveguide according to claim 17, further comprising a third epoxy resin layer between the conductive winding and the second coating.

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