The present subject matter relates generally to harvesting implements for agricultural vehicles, and, more particularly, to systems and methods for controlling the height of a harvesting implement relative to a ground surface.
A harvester is an agricultural machine that is used to harvest and process crops. For instance, a forage harvester may be used to cut and comminute silage crops, such as grass and corn. Similarly, a combine harvester may be used to harvest grain crops, such as wheat, oats, rye, barely, corn, soybeans, and flax or linseed. In general, the objective is to complete several processes, which traditionally were distinct, in one pass of the machine over a particular part of the field. In this regard, most harvesters are equipped with a detachable harvesting implement, such as a header, which cuts and collects the crop from the field and feeds it to the base harvester for further processing.
Conventionally, the operation of most harvesters requires substantial operational involvement and control by the operator. For example, with reference to a combine, the operator is typically required to control various operating parameters, such as the direction of the combine, the speed of the combine, the height and tilt of the combine header, the air flow through the combine cleaning fan, the amount of harvested crop stored on the combine, and/or the like. To address such issues, many current combines utilize an automatic header height control system that attempts to maintain a constant cutting height above the ground regardless of the ground contour or ground position relative to the base combine. For instance, it is known to utilize electronically controlled height and tilt cylinders to automatically adjust the height and lateral orientation, or tilt, of the header relative to the ground based on sensor measurements received from a plurality of sensors mounted on the header. These header-based sensor arrangements typically rely on detecting a distance between each sensor and the ground surface for subsequent use as the basis for header height control. However, the position of the header, itself, (and, thus, any sensors coupled thereto) is constantly changing relative to the ground surface as, for example, the wheels of the harvester encounter terrain variations. As a result, variations in the distance measurements provided by the header-based sensors are due to changes in the position of the header relative to the ground surface as opposed to actual changes in the profile of the ground surface, thereby leading to issues with accurately maintaining a desired header height.
Accordingly, improved systems and methods for controlling the height of a harvesting implement relative to the ground that addresses one or more of the issues in the prior art would be welcomed in the technology.
Aspects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.
In one aspect, the present subject matter is directed to a method for automatically controlling a height of a harvesting implement of an agricultural work vehicle relative to a ground surface, with the harvesting implement being provided in operative association with an actuator configured to adjust a vertical height of at least a portion of the harvesting implement relative to the ground surface. The method includes receiving, with a computing system, distance data from a distance sensor supported relative to the harvesting implement that is indicative of a measured distance from the distance sensor to a location on the ground surface positioned forward of the harvesting implement, and receiving, with the computing system, pose data indicative of both an absolute pose and a relative pose of the distance sensor. The method also includes determining, with the computing system, a pose of the distance sensor based on the pose data, and determining, with the computing system, a compensation value for adjusting the measured distance based on the pose of the distance sensor. Additionally, the method includes calculating, with the computing system, a compensated distance value as a function of the measured distance and the compensation value, and controlling, with the computing system, an operation of the actuator based at least in part on the compensated distance value to adjust the vertical height of the at least a portion of the harvesting implement relative to the ground surface.
In another aspect, the present subject matter is directed to a height control system for an agricultural work vehicle. The system includes a harvesting implement and an actuator configured to adjust a vertical height of at least a portion of the harvesting implement relative to a ground surface. The system also includes a distance sensor supported relative to the harvesting implement, with the distance sensor configured to generate distance data indicative of a distance from the distance sensor to a location on the ground surface positioned forward of the harvesting implement. Additionally, the system includes a sensor positioning assembly comprising first and second pose measurement devices. The first pose measurement device is configured to generate pose data indicative of an absolute pose of the distance sensor, and the second pose measurement device is configured to generate pose data indicative of a relative pose of the distance sensor. Moreover, the system includes a computing system communicatively coupled to the distance sensor and the sensor positioning assembly. The computing system is configured to determine an initial distance value associated with the distance from the distance sensor to the ground surface based on the distance data received from the distance sensor, and determine a pose of the distance sensor based on the pose data received from the first and second pose measurement devices. Additionally, the computing system is configured to determine a compensation value for adjusting the initial distance value based on the pose of the distance sensor, calculate a compensated distance value as a function of the initial distance value and the compensation value, and control an operation of the actuator based at least in part on the compensated distance value to adjust the vertical height of the at least a portion of the harvesting implement relative to the ground surface.
These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.
A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:
Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.
In general, the present subject matter is directed to systems and methods for controlling the height of a harvesting implement relative to a ground surface. Specifically, in several embodiments, the disclosed system includes one or more distance sensors supported relative to a harvesting implement, with the distance sensor(s) being configured to detect a distance between the sensor(s) and one or more points along the ground surface at a location(s) forward of the harvesting implement. Additionally, the system includes one or more sensor positioning assemblies for generating pose data associated with a position and angular orientation of the distance sensor(s). In several embodiments, each sensor positioning assembly may include both a first pose measurement device for generating pose data associated with an absolute pose of the distance sensor(s) relative to a world coordinate system and a second pose measurement device for generating pose data associated with a relative pose of the sensor(s).
In accordance with aspects of the present subject matter, the pose data provided by the sensor positioning assembly may be used to calculate a distance compensation value that can be applied to the distance measurements provided by the distance sensor(s) to generate a more accurate profile/map of the ground surface. Specifically, in embodiments in which the distance sensor(s) is supported on the harvesting implement, the sensor(s) will move relative to the ground surface with, for example, movement of the implement together with the harvester's chassis (e.g., when the chassis shifts up/down as the wheels encounter terrain variations along the ground surface). As a result, with such movement of the distance sensor(s), variations in the distance detected by the sensor(s) are not necessarily due to variations in the ground profile itself, but rather are often due to changes in the pose of the sensor(s) relative to the ground surface. Accordingly, the pose data provided by the sensor positioning assembly may be used to correct the distance data to compensate for movement of the distance sensor(s) within a world or global frame of reference, thereby providing compensated distance data that is indicative of an absolute profile of the ground surface. The estimated ground profile (e.g., as determined via the compensated distance data) may then, for example, be used to actively control the height of the harvesting implement and/or to generate a terrain map of the field in which the harvester is operating.
Referring now to the drawings,
Moreover, as shown in
As the harvester 10 is propelled forwardly over a field with standing crop, the crop material is severed from the stubble by a sickle bar 42 at the front of the header 32 and delivered by a header auger 44 to the front end 36 of the feeder 34, which supplies the cut crop to the threshing and separating assembly 24. As is generally understood, the threshing and separating assembly 24 may include a cylindrical chamber 46 in which the rotor 12 is rotated to thresh and separate the crop received therein. That is, the crop is rubbed and beaten between the rotor 12 and the inner surfaces of the chamber 46, whereby the grain, seed, or the like, is loosened and separated from the straw.
Crop material which has been separated by the threshing and separating assembly 24 falls onto a series of pans 48 and associated sieves 50, with the separated crop material being spread out via oscillation of the pans 48 and/or sieves 50 and eventually falling through apertures defined in the sieves 50. Additionally, a cleaning fan 52 may be positioned adjacent to one or more of the sieves 50 to provide an air flow through the sieves 50 that removes chaff and other impurities from the crop material. For instance, the fan 52 may blow the impurities off of the crop material for discharge from the harvester 10 through the outlet of a straw hood 54 positioned at the back end of the harvester 10.
The cleaned crop material passing through the sieves 50 may then fall into a trough of an auger 56, which may be configured to transfer the crop material to an elevator 58 for delivery to the associated holding tank 28. Additionally, a pair of tank augers 60 at the bottom of the holding tank 28 may be used to urge the cleaned crop material sideways to an unloading tube 62 for discharge from the harvester 10.
Moreover, in several embodiments, the harvester 10 may also include a hydraulic system 70 which is configured to adjust a height of the header 32 relative to the ground surface 19 so as to maintain the desired cutting height between the header 32 and the ground surface 19. The hydraulic system 70 may include a height actuator 72 (e.g., a fluid-actuated cylinder) configured to adjust the height or vertical positioning of the header 32 relative to the ground. For example, in some embodiments, the height actuator 72 may be coupled between the feeder 34 and the frame 14 such that the height actuator 72 may pivot the feeder 34 to raise and lower the header 32 relative to the ground 19. In addition, the hydraulic system 70 may include a tilt actuator(s) 74 (e.g., a fluid-actuated cylinder) coupled between the header 32 and the feeder 34 to allow the header 32 to be tilted relative to the ground surface 19 or pivoted laterally or side-to-side relative to the feeder 34.
Additionally, in accordance with aspects of the present subject matter, the harvester 10 may include one or more distance sensors 102 (one of which is shown in
In general, the distance sensor(s) 102 may correspond to any suitable sensor device or assembly that is capable of detecting the distance 104 between the sensor(s) 102 and the ground surface 19. In several embodiments, the distance sensor(s) 102 may correspond to one or more non-contact sensors. For instance, in one embodiment, the distance sensor(s) 102 may correspond to one or more radar devices. In another embodiment, the distance sensor(s) 102 may correspond to one or more light detection and ranging (LIDAR) devices and/or one or more imaging devices (e.g., one or more cameras, such as stereo cameras). In other embodiments, the distance sensor(s) 102 may correspond to any other suitable non-contact-based sensor devices and/or assemblies (e.g., ultrasound sensors) or any suitable contact-based sensor devices and/or assemblies. Additionally, in one embodiment, the distance sensor(s) 102 may include a combination of different sensor types, such as a combination of radar devices and LIDAR devices.
Moreover, as shown in
As will be described below, the pose data provided by the sensor positioning assembly 106 may be used to calculate a distance compensation value that can be applied to the distance measurements provided by the distance sensor(s) 102 to generate a more accurate profile/map of the ground surface 19. Specifically, since the distance sensor(s) 102 is supported on the header 32 in the illustrated embodiment, the sensor(s) 102 moves relative to the ground surface 19 with movement of the header 32 relative to the chassis 14 (e.g., via operation of the lift/tilt actuators 72, 74) and with movement of the header 32 with the chassis 14 (e.g., when the chassis 14 shifts up/down as the wheels 16, 18 encounter terrain variations along the ground surface 19). As a result, with such movement of the distance sensor(s) 102, variations in the distance 104 detected by the sensor(s) 102 are not necessarily due to variations in the ground profile itself, but rather due simply to changes in the position/pose of the sensor(s) 102 relative to the ground surface 19. Accordingly, the pose data provided by the sensor positioning assembly 106 may be used to correct the distance data to compensate for movement of the distance sensor(s) 102 within a world or global frame of reference, thereby providing compensated distance data that is indicative of an absolute profile of the ground surface 19. The estimated ground profile (e.g., as determined via the compensated distance data) may then, for example, be used to actively control the header height, such as by implementing a closed-loop control algorithm.
Referring now to
In one embodiment, the hydraulic system 70 may include a pair of tilt actuators 74. For instance, as shown in
In general, the operation of the height actuator 72 and tilt actuator(s) 74 may be controlled (e.g., via an associated controller or computing system) to adjust the vertical positioning and tilt angle of the header 32 relative to the ground surface 19. For instance, as indicated above, one or more distance sensors 102 may be supported on the header 32 to generate distance data associated with the distance 104 defined between the sensor(s) 102 and the ground surface 19, which may, in turn, be indicative of a corresponding distance 112 between the header 32 and the ground surface 19 at each measurement location (only one distance 112 being labeled in
As indicated above with reference to
As described above with reference to
It should be appreciated that, in other embodiments, the sensor positioning assemblies 106 may, instead, be spaced apart or positioned distal relative to their respective distance sensors 102. In such embodiments, any changes in the pose detected by each sensor positioning assembly 106 at the installed location thereof may be correlated to the relative pose of the respective distance sensor 102 based on the known spacing/mounting relationship between such devices and the kinematics of the harvester 10. Additionally, in one embodiment, a single sensor positioning assembly 106 may be used to generate pose data for each of the distance sensors 102. In such an embodiment, any changes in the pose detected by such positioning assembly 106 at the installed location thereof may be correlated to the relative pose of each of the distance sensors 102 based on the known spacing/mounting relationship between such devices and the kinematics of the harvester 10.
Referring now to
In one embodiment, the terrain map 90 generated in accordance with aspects of the present subject matter may be continuously stored within an associated controller or computing system (described below with reference to
Referring now to
As shown, the control system 100 may include any combination of components of the harvester 10 and header 32 described above with reference to
Additionally, as shown in
By using the combination of and the first and second pose measurement devices 108, 110, a more accurate estimate of the pose of the distance sensor(s) 102 may be provided relative to a global reference frame. For example, while the first pose measurement device 108 (e.g., a satellite-based positioning device) is equipped to provide accurate pose data over time, the low frequency pose data generated by such device 108 is often not capable of accurately detecting quick changes in the pose of the distance sensor(s) 102. Similarly, while the second pose measurement device 110 (e.g., an IMU) is equipped to detect quick changes in the pose of the distance sensor(s) 102, such high frequency pose data will often drift over time. Thus, by combining the pose data provided by both measurement devices 108110, a highly accurate estimate of the pose of the distance sensor(s) 102 relative to a global reference frame can be provided. In several embodiments, the data generated by the measurement devices 108, 110 may be combined via sensor fusion to provide an accurate estimate of the current pose of the distance sensor(s) 102 (e.g., including a current absolute position of the distance sensor(s) 102 and a current angular orientation of the distance sensor(s) 102. For instance, in one embodiment, the current pose of the distance sensor(s) 102 may be calculated as a weighted sum of a low-pass filtered value of the absolute pose estimate determined via the first pose measurement device 108 and a high-pass filtered value of the relative pose estimate determined via the second pose measurement device 110.
Referring still to
In one embodiment, the memory 124 of the computing system 120 may include one or more databases for storing information associated with the operation of the harvester 10, including data associated with controlling the height of the header 32. For instance, as shown in
Additionally, the memory 124 may include a pose database 126 for storing data associated with the pose data provided by each sensor positioning assembly 106, including initial pose data provided by each of the pose measurement devices 108, 110 and final pose data for each distance sensor(s) 102 as determined based on the initial pose data. Specifically, the computing system 120 may be commutatively coupled to both the first pose measurement device 108 and the second pose measurement device 110 of each sensor positioning assembly 106 to allow the pose-related data generated by such devices 108, 110 to be transmitted to the computing system 120. As such, the computing system 120 may be configured to continuously determine/monitor the pose of each distance sensor 102 to allow the computing system 120 to detect changes in the absolute position and/or angular orientation of such sensor 102.
Moreover, as shown in
Referring still to
For instance, if the distance correction module 132 determines that the absolute position of the distance sensor(s) 102 has increased six inches (6″) from a baseline sensor position set for such sensor(s) 102, a corresponding compensation value of negative 6 inches (−6″) may be used to adjust the distance measurement provided by the distance sensor(s) 102 (e.g., by subtracting six inches from the distance measurement) to account for such an increase in the vertical height of the sensor(s) 102. Similarly, if the distance correction module 132 determines that the absolute position of the distance sensor(s) 102 has decreased 4 inches (4″) from the baseline sensor position set for the sensor(s) 102, a corresponding compensation value of positive 4 inches (+4″) may be used to adjust the distance measurement provided by the distance sensor(s) 102 (e.g., by adding four inches to the distance measurement) to account for such a decrease in the vertical height of the sensor(s) 102.
Additionally, if the distance correction module 132 determines that the angular orientation of the distance sensor(s) 102 has changed relative to a baseline angular orientation set for the distance sensor(s) 102, a corresponding compensation value may be selected to adjust the distance measurement provided by the distance sensor(s) 102 to account for such a change in angular orientation of the sensor(s) 102. For instance, in one embodiment, one or more look-up tables or mathematical expressions may be developed and stored within the memory 124 of the computing system 120 that correlate distance-related compensation values to changes in the pitch angle, roll angle, and/or tilt angle of the distance sensor(s) 102 relative to the baseline angular orientation set for the sensor(s) 102. In such an embodiment, when it is determined that the angular orientation of the distance sensor(s) 102 has changed relative to the baseline angular orientation along one or more axes, the look-up table(s) and/or mathematical expression(s) may be used to select an appropriate compensation value for correcting the distance measurement provided by the distance sensor(s) 102.
It should be appreciated that the look-up table(s) or mathematical expression(s) used to correlate distance-related compensation values to changes in the angular orientation of the distance sensor(s) 102 may be developed experimentally or may be developed mathematically and/or via modeling. It should also be appreciated that, in one embodiment, a suitable look-up table(s) or mathematical expression(s) may be developed that correlates distance-related compensation values to changes in both the angular orientation and absolute position of the distance sensor(s) 102. Alternatively, individual compensation values accounting for changes in the angular orientation and absolute position of the distance sensor(s) 102 may be calculated separately and subsequently combined (e.g., by summing the compensation values) to determine a final compensation value for adjusting the initial distance measurement provided via the distance sensor(s) 102.
Moreover, it should be appreciated that, in addition to compensating the measured distance provided by the distance sensor(s) 102, the computing system 120 may also be configured to compensate or correct the coordinates of the location at which the distance sensor(s) 102 is sensing the ground profile. For instance, changes in the angular orientation of the distance sensor(s) 102 may result in the sensor(s) 102 detecting the ground at a location further out in front of or closer towards the header 32. As such, the computing system 120 may be configured to take into account changes in the pose of the distance sensor(s) 102 when determining the location at which the ground is being sensed relative to a known reference point (e.g., a known reference point on the harvester 10, such as the front axle, or a known reference point on the header 32).
Referring still to
Moreover, as shown in
In accordance with aspects of the present subject matter, the height control module 136 may be configured to control the operation of the height actuator 72 and/or the tilt actuator 74 to maintain the height of the header 32 at a desired or predetermined height setting value(s), such as an operator selected target height or target height range. In doing so, the height control module 136 may, in several embodiments, be configured to execute a closed-loop control algorithm for generating control outputs for controlling the operation of the height actuator 72 and/or the tilt actuator 74 via the associated control valve(s) 140, 142. For instance, as will be described below, the computing system 120 may be configured to execute feedback control to maintain the height of the header 32 at the target height setting.
It should be appreciated that the computing system 120 may also include various other suitable components, such as a communications circuit or module 150, a network interface, one or more input/output channels, a data/control bus and/or the like, to allow the computing system 120 to be communicatively coupled with any of the various other system components described herein.
Moreover, as shown in the illustrated embodiment, the computing system 120 may also be communicatively coupled to a user interface 152 of the harvester 10. In general, the user interface 152 may correspond to any suitable input device(s) configured to allow the operator to provide operator inputs to the computing system 120, such as a touch screen display, a keyboard, joystick, buttons, knobs, switches, and/or combinations thereof located within the cab 22 of the harvester 10. The operator may provide various inputs into the system 100 via the user interface 152. In one embodiment, suitable operator inputs may include, but are not limited to, a target height for the header 32, a target height range for the header 32, and/or any other parameter associated with controlling the height of the header 32. In addition, the user interface 152 may also be configured to provide feedback (e.g., feedback associated with an operator selected target height and/or height range of the header 32) to the operator. As such, the user interface 152 may include one or more output devices (not shown), such as display screens, speakers, warning lights, and/or the like, which are configured to provide feedback from the computing system 120 to the operator.
Referring now to
As shown in
Additionally, as shown in
Additionally, as indicated above, the target height setting selected by the first controller 202 may be input as a setpoint (e.g., as indicated by box 220) into the second controller 204 of the computing system 120, which may be configured to generate an error-based feedback control output for controlling the operation of the control valve(s) 140, 142. Specifically, in several embodiments, the second controller 204 may be configured to determine the error between target height setting and a measured height of the header 32, which may then be used to calculate a speed at which the header 32 needs to be made in order to maintain the header 32 at the target height setting relative to the ground surface 19. Thus, as shown in
It should be appreciated that the measured header height signal 222 may, in several embodiments, generally derive from any suitable header height data (e.g., as indicated by box 234). For instance, in several embodiments, a separate set of contact-based sensors (e.g., mechanical feelers) may be supported on the header 32 for providing data associated with the current header height relative to the ground surface 19. In such embodiments, the header height data 234 may correspond to or derive from the data provided by the contact-based sensors. In another embodiment, the header height data 234 may derive from the compensated distance values generated by the computing system 120. For instance, with the distance sensor(s) 102 mounted at a known location relative to the header 32 (including a known vertical offset from the bottom of the header 32), the actual header height relative to the ground surface 19 at each location across the lateral width of the header 32 may be calculated by subtracting the vertical offset distance defined between the bottom of the header 32 and the distance sensor(s) 102 from the corresponding compensated distance values.
Referring still to
Referring now to
As shown in
Additionally, at (304), the method 300 includes receiving pose data indicative of both an absolute pose and a relative pose of the distance sensor. Specifically, as indicated above, the computing system 120 may be communicatively coupled to a sensor positioning assembly 106 including a first pose measurement device 108 and a second pose measurement device 110. In such an embodiment, the computing system 120 may be configured to receive pose-related data from the first pose measurement device 108 that is indicative of the absolute pose of an associated distance sensor(s) 102 along with pose-related data from the second pose measurement device 110 that is indicative of the relative pose of such sensor(s) 102.
Moreover, at (306) and (308), the method 300 includes determining a pose of the distance sensor based on the pose data and determining a compensation value for adjusting the measured distance based on the pose of the distance sensor. For example, as indicated above, the computing system 120 may be configured to monitor the pose data received from the sensor positioning assembly 106 to detect changes in the absolute position and/or orientation of the distance sensor(s) 102. By detecting the change in the absolute position and/or orientation of the distance sensor(s) 102, the computing system 120 may then be configured to calculate a compensation value for adjusting the distance measurement(s) initially generated based on the distance data provided from the sensor(s) 102.
Referring still to
Additionally, at (312), the method 300 includes controlling an operation of an actuator based at least in part on the compensated distance value to adjust a vertical height of at least a portion of the harvesting implement relative to the ground surface. Specifically, as indicated above, the computing system 120 may be configured to control the operation of the height actuator 72 and/or the tilt actuator(s) 74 to adjust the vertical height of the header 32. For instance, in one embodiment, the computing system 120 may be configured to adjust the header height using a closed-loop control algorithm to maintain the header 32 at a predetermined target height setting (e.g., an operator-selected height setting).
It is to be understood that the steps of the method 300 are performed by the computing system 120 upon loading and executing software code or instructions which are tangibly stored on a tangible computer readable medium, such as on a magnetic medium, e.g., a computer hard drive, an optical medium, e.g., an optical disc, solid-state memory, e.g., flash memory, or other storage media known in the art. Thus, any of the functionality performed by the computing system 120 described herein, such as the method 300, is implemented in software code or instructions which are tangibly stored on a tangible computer readable medium. The computing system 120 loads the software code or instructions via a direct interface with the computer readable medium or via a wired and/or wireless network. Upon loading and executing such software code or instructions by the computing system 120, the computing system 120 may perform any of the functionality of the computing system 120 described herein, including any steps of the method 300 described herein.
The term “software code” or “code” used herein refers to any instructions or set of instructions that influence the operation of a computer or controller. They may exist in a computer-executable form, such as machine code, which is the set of instructions and data directly executed by a computer's central processing unit or by a controller, a human-understandable form, such as source code, which may be compiled in order to be executed by a computer's central processing unit or by a controller, or an intermediate form, such as object code, which is produced by a compiler. As used herein, the term “software code” or “code” also includes any human-understandable computer instructions or set of instructions, e.g., a script, that may be executed on the fly with the aid of an interpreter executed by a computer's central processing unit or by a controller.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
Filing Document | Filing Date | Country | Kind |
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PCT/US2022/035662 | 6/30/2022 | WO |
Number | Date | Country | |
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63216748 | Jun 2021 | US |