Method for calibrating a height control system for an agricultural work vehicle implement and height control system for an agricultural work vehicle implement

Abstract

This is a method and system for calibrating a height control system for an implement on an agricultural work vehicle. It describes a method for calibrating a height control system for an implement on an agricultural work vehicle that may include providing an input signal to the height control system to adjust the implement height relative to the ground surface; monitoring the implement height relative to the ground surface; adjusting at least one gain of the height control system; and determining a maximum stability gain of the height control system based on at least one gain and the monitored height. The maximum stability gain may correspond to a stability point of the height control system at which the height control system transitions from stable to unstable. The method may include setting the gain (or gains) of the height control system based on the maximum stability gain.

Description

1 / 24 “METHOD FOR CALIBRATING A HEIGHT CONTROL SYSTEM FOR AN AGRICULTURAL WORK VEHICLE IMPLEMENT AND HEIGHT CONTROL SYSTEM FOR AN AGRICULTURAL WORK VEHICLE IMPLEMENT” FIELD OF THE INVENTION

[001] The present material relates, in general, to height control systems for agricultural implements and, more particularly, to a method and system for calibrating a height control system for an implement of an agricultural work vehicle. BACKGROUND OF THE INVENTION

[002] A combine harvester is an agricultural machine that is used to harvest and process crops. For example, a forage harvester can be used to cut and shred silage crops, such as grass and corn. Similarly, a combination harvester can be used to harvest grain crops, such as wheat, oats, rye, barley, corn, soybeans, and flax or linseed. In general, the goal is to complete several processes, which were traditionally distinct, in one pass of the machine through a particular part of the field. In this respect, most combine harvesters are equipped with a detachable harvesting implement, such as a platform, which cuts and collects the crop from the field and provides it to the base combine harvester for further processing.

[003] In conventional terms, the operation of most combine harvesters requires substantial control and operational involvement by the operator. For example, with reference to a combine harvester, the operator is typically required to control several operational parameters, such as the direction of the combine harvester, the speed of the combine harvester, the height of the combine harvester platform, the airflow through the combine harvester cleaning fan, and the amount of harvested crop stored in the combine harvester; Petition 870250084860, dated 09 / 19 / 2025, page 13 / 73 2 / 24 and / or similar. To address such issues, many current combine harvesters utilize an automatic platform height and tilt control system to maintain a constant cutting height above ground regardless of ground contour or ground position relative to the combine harvester base. For example, electronically controlled height and tilt cylinders are known to be used to automatically adjust the platform height and orientation, or lateral tilt, relative to the ground based on sensor measurements. However, such systems often exhibit significant lag and slow response times, particularly when the combine is operating at high ground speeds. The parameters of such systems can be selected to improve performance. Determining ideal parameters for such a control system, however, can be difficult.

[004] Consequently, an improved method and related system for calibrating a height control system for an implement of an agricultural work vehicle that addresses one or more of the problems identified above would be well received in the technology field. DESCRIPTION OF THE INVENTION

[005] Aspects and advantages of the invention will be presented in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.

[006] In one aspect, the present matter is directed to a method for calibrating a height control system for an implement of an agricultural work vehicle which may include providing an input signal to the height control system to adjust the implement height relative to the ground surface; monitoring the implement height relative to the ground surface; adjusting at least one gain of the height control system; and determining a maximum stability gain of the height control system based on at least one gain and the height. Petition 870250084860, dated 09 / 19 / 2025, p. 14 / 73 3 / 24 monitored. The maximum stability gain may correspond to a stability point of the height control system at which the height control system transitions from stable to unstable. The method may include defining the height control system gain (or gains) based on the maximum stability gain.

[007] In another aspect, the present material is directed to a height control system for an implement of an agricultural work vehicle. The height control system may include an implement and an implement height sensor configured to detect the implement height relative to a ground surface. The height control system may include an implement controller communicatively coupled to the implement height sensor. The implement controller may include a processor and associated memory. The memory may store instructions that, when executed by the processor, configure the implement controller to perform operations.Operations may include providing an input signal to the height control system to adjust the implement height relative to the ground surface; monitoring the implement height relative to the ground surface based on signals received from the implement height sensor; adjusting at least one gain of the height control system; and determining a maximum stability gain of the height control system based on at least one gain and the monitored height. The maximum stability gain may correspond to a stability point of the height control system at which the height control system transitions from stable to unstable. Operations may include setting the gain (or gains) of the height control system based on the maximum stability gain.

[008] In a further aspect, the present matter is directed to a height control system for an implement of an agricultural work vehicle. The height control system may include an implement and an implement height sensor configured to detect the implement height relative to a Petition 870250084860, dated 09 / 19 / 2025, p. 15 / 73 4 / 24 ground surface. The height control system may include an implement controller communicatively coupled to the implement height sensor. The implement controller may include a processor and associated memory. The memory may store instructions that, when executed by the processor, configure the implement controller to perform operations. Operations may include monitoring the implement height relative to the ground surface based on signals received from the implement height sensor; determining an implement height error by comparing the implement height to a predetermined target height; calculating an output signal based on the implement height using at least one gain from the implement controller; and adjusting the implement height based on the output signal.The implement controller gain (or gains) may have been calibrated by providing an input signal to the implement controller; monitoring the implement height relative to the ground surface; adjusting the implement controller gain (or gains); determining a maximum implement controller stability gain based on at least one gain; and setting the implement controller gain (or gains) based on the determined maximum stability gain.

[009] These and other features, aspects and advantages of the present invention will become better understood with reference to the description and claims appended below. The accompanying drawings, which are incorporated into and form part of this descriptive report, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[010] A complete and enabling description of the present invention, which includes the best embodiment thereof, directed to a common skill element in the art, is presented in the descriptive report, which refers to the attached figures, in which: Petition 870250084860, dated 09 / 19 / 2025, page 16 / 73 5 / 24

[011] Figure 1 illustrates a simplified partial side cutaway view of an embodiment of an agricultural vehicle, in accordance with aspects of the present matter;

[012] Figure 2 illustrates a simplified schematic view of an embodiment of a hydraulic system for an agricultural harvester in accordance with aspects of the present matter;

[013] Figure 3 illustrates a schematic view of an embodiment of a system for calibrating a height control system for an implement of an agricultural work vehicle in accordance with aspects of the present matter;

[014] Figure 4 illustrates a flowchart showing an embodiment of a method for calibrating a height control system for an implement of an agricultural work vehicle in accordance with aspects of the present matter;

[015] Figure 5 provides a simplified illustrative plot of an input signal, a first monitored implement height for a first gain that is less than the maximum stability gain, and a second monitored implement height for a second gain that is greater than a maximum stability gain determined according to aspects of the present matter; and

[016] Figure 6 provides a simplified example plot of an input signal and a third monitored implement height for a third gain that is approximately equal to a maximum stability gain determined according to aspects of the present subject matter. DESCRIPTION OF THE INVENTION'S EMPHASIS

[017] Reference will now be made in detail to the embodiments of the invention, one or more examples thereof being illustrated in the drawings. Each example is given by way of explanation of the invention, and not as a limitation of the invention. Indeed, it will be evident to those skilled in the art that various modifications and variations can be made to the present invention without departing from the scope and spirit of the invention. For example, the functions illustrated or described Petition 870250084860, dated 09 / 19 / 2025, page 17 / 73 6 / 24 as part of an embodiment can be used with another embodiment to produce a still more advanced embodiment. Thus, the present invention is intended to cover such modifications and variations, as included in the scope of the appended claims and their equivalents.

[018] In general, the present material is directed to a method for calibrating a height control system for an implement of an agricultural work vehicle. The calibration method can be performed between agricultural operations (e.g., harvesting operations), for example, while the work vehicle is stationary. The height control system can be configured to implement a proportional-integral (“PI”) or proportional-integral-derivative (“PID”) control loop to adjust the implement height during an agricultural operation. An input signal (e.g., a slope input) can be entered into the height control system to adjust an implement height relative to the ground surface. The response of the height control system to the input signal can be measured. More specifically, the method may include monitoring the implement height relative to the ground surface.An implement height sensor can detect the implement height as the vehicle control system adjusts the implement height in response to the input signal. One or more height control system gains can be automatically set based on a maximum stability gain of the height control system. The maximum stability gain can correspond to a stability point of the height control system at which the height control system transitions from stable to unstable, for example as described below with reference to Figures 5 and 6. The height control system gain(s) can be selected to provide desirable response characteristics for particular properties and / or dynamics of the height control system, such as platform height. As an example, the gain(s) can include one or more of a proportional signal gain, an integral signal gain, etc. Petition 870250084860, dated 09 / 19 / 2025, page 18 / 73 7 / 24 and a derived signal gain.

[019] In one embodiment, one or more system gains can be determined by increasing the gain (or gains) until it is approximately equal to the maximum stability gain. An operational gain (or gains) of the height control system can then be calculated based on the maximum stability gain, for example, using predetermined relationships, equations, lookup tables, etc. Some or all of the steps can be performed automatically by the height control system. In this way, a desirable and / or ideal gain (or gains) for the height control system can be quickly and / or automatically determined according to aspects of the present disclosure.

[020] Referring now to the drawings, Figure 1 illustrates a simplified partial cutaway side view of an embodiment of a work vehicle, a combine harvester 10. The combine harvester 10 can be configured as a combined axial flow type combine harvester, in which crop material is threshed and separated as it advances through and along a longitudinally arranged rotor 12. The combine harvester 10 may include a chassis or main frame 14 having a pair of front ground-engaging drive wheels 16 and a pair of rear steerable wheels 18. The wheels 16, 18 can be configured to support the combine harvester 10 relative to a ground surface 19 and move the combine harvester 10 in a forward direction of movement 21 relative to the ground surface 19.Additionally, an operator platform 20 with an operator cab 22, a threshing and separation assembly 24, a grain cleaning assembly 26, and a holding tank 28 can be supported by the frame 14. Furthermore, as is generally understood, the combine harvester 10 may include an engine and a transmission mounted on the frame 14. The transmission may be operationally coupled to the engine and may provide variably adjusted gear ratios to transfer engine power to the wheels via a set of geometric drive shafts for transfer. Petition 870250084860, dated 09 / 19 / 2025, p. 19 / 73 8 / 24 power to wheels 16, 18 via a set of geometric drive shafts (or via geometric shafts if multiple drives are used).

[021] Furthermore, as shown in Figure 1, a harvesting implement (e.g., a platform 32) and an associated feeder 34 may extend forward from the main frame 14 and may be pivotally attached to it for generally vertical movement. In general, the feeder 34 may be configured to serve as a support structure for the platform 32. As shown in Figure 1, the feeder 34 may extend between a front end 36 coupled to the platform 32 and a rear end 38 positioned adjacent to the threshing and separation assembly 24. As is generally understood, the rear end 38 of the feeder 34 may be pivotally coupled to a portion of the combine harvester 10 to allow the front end 36 of the feeder 34, and thus the platform 32, to be moved up and down relative to the ground 19 to set the desired harvesting and cutting height for the platform 32.

[022] As the combine harvester 10 is driven forward over a field where the crop is located, the crop material is cut from the stubble by a cutter bar 42 in front of the platform 32 and delivered by a drill platform 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, so that the grain, seed or similar is loosened and separated from the straw.

[023] The culture material that has been separated by the threshing and separation assembly 24 falls into a series of trays 48 and associated sieves 50, where the separated culture material is spread by means of oscillation of the trays 48 Petition 870250084860, dated 09 / 19 / 2025, p. 20 / 73 9 / 24 and / or sieves 50 and eventually falls through the openings 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 airflow through the sieves 50 that removes straw and other impurities from the crop material. For example, the fan 52 may blow the impurities out of the crop material to discharge from the combine harvester 10 through the outlet of a straw hood 54 positioned at the rear of the combine harvester 10.

[024] The clean crop material that passes through the sieves 50 can then fall into a channel of an auger 56, which can be configured to transfer the crop material to an elevator 58 to deliver to the associated holding tank 28. Additionally, a pair of tank augers 60 at the bottom of the holding tank 28 can be used to propel the clean crop material laterally to a discharge tube 62 to discharge from the combine harvester 10.

[025] In addition, in several embodiments, the combine harvester 10 may also include a hydraulic system 100 that is configured to adjust a platform height 32 relative to the ground 19 in order to maintain the desired cutting height between the platform 32 and the ground 19. The hydraulic system 100 may include a height control cylinder 101 configured to adjust the platform height 32 relative to the ground. For example, in some embodiments, the height control cylinder 101 may be coupled between the feeder 34 and the frame 14 so that the height control cylinder 101 can pivot the feeder 34 to raise the platform 32 relative to the ground 19. In some embodiments, the hydraulic system 100 may include first and second tilt cylinders 102, 104 coupled between the platform 32 and the feeder 34 to allow the platform 32 to be tilted relative to the ground 19 or pivoted laterally or side-to-side relative to the feeder 34.

[026] Now with reference to Figure 2, a simplified schematic view of an embodiment of the hydraulic system 100 described above with reference to Figure 1 is Petition 870250084860, dated 09 / 19 / 2025, page 21 / 73 Figure 10 / 24 illustrates aspects of the present matter. As shown, the platform 32 can generally extend side-by-side or in a lengthwise direction (indicated by arrow 105 in Figure 2) between a first lateral end 106 and a second lateral end 108. Additionally, the platform 32 can be coupled to the feeder 34 at a location between its first and second lateral ends 106, 108 to allow the platform 32 to tilt laterally relative to the feeder 34 (for example, as indicated by arrows 112, 114 in Figure 2). For example, the platform 32 can be coupled to the feeder 34 approximately at a center 110 of the platform 32. The height control cylinder 101 can be configured to raise and lower the end of the feeder 34 relative to the combine frame 14 (for example, as indicated by arrow 115).The side tilt cylinders 102, 104 can be configured to tilt the platform 32 laterally relative to the ground 19 (for example, as indicated by arrows 112, 114). In some embodiments, the tilt cylinders 102, 104 can also be configured to raise and lower the platform 32 relative to the feeder 34 (for example, as indicated by arrow 113).

[027] As indicated above, the hydraulic system 100 may include the height control cylinder 101 and one or more tilt cylinders 102, 104. For example, as shown in the illustrated embodiment, a first tilt cylinder 102 may be coupled between the platform 32 and the feeder 34 along one side of the connection between the platform 32 and the feeder 34, and a second tilt cylinder 104 may be coupled between the platform 32 and the feeder 34 along the opposite side of the connection between the platform 32 and the feeder 34. In general, the operation of the height control cylinder 101 and the tilt cylinders 102, 104 may be controlled (for example, by means of an associated controller) to adjust the height and angle of the platform 32 relative to the ground 19. For example, one or more Petition 870250084860, dated 09 / 19 / 2025, page 22 / 73 11 / 24 height sensors 116, 118, 119 can be provided on platform 32 to monitor one or more respective local distances or heights 120 defined between platform 32 and the ground 19. Specifically, as shown in Figure 2, a first height sensor 116 can be provided at or adjacent to the first lateral end 106 of platform 32, and a second height sensor 118 can be provided at or adjacent to the second lateral end 108 of platform 32. In some embodiments, a third height sensor 119 can be provided at or adjacent to the center 110 of platform 32.In such an embodiment, when one of the height sensors 116, 118, 119 detects that the local height 120 defined between the platform 32 and the ground 19 differs from a desired height (or is outside a desired height range), the height control cylinder 101 and / or the tilt cylinders 102, 104 can be actively controlled to adjust the height and / or tilt of the platform 33 so as to keep the platform 32 at the desired height (or within the desired height range) relative to the ground 19. In some embodiments, the desired height may be an average, weighted average, or other suitable mathematical combination of the local heights 120 measured by one or more of the height sensors 116, 118, 119.

[028] Referring now to Figure 3, a schematic view of an embodiment of a control system 200 is provided for automatically controlling the height of an agricultural implement (such as the platform 32 of the combine harvester 10 described above) relative to the ground 19 according to aspects of the present matter. In general, the control system 200 will be described in the present document with reference to the combine harvester 10 and platform 32 illustrated in Figure 1. However, it should be noted that the disclosed control system 200 can be implemented to control the height of any suitable agricultural implement associated with a work vehicle having any other suitable configuration.

[029] As shown, the 200 control system can generally include Petition 870250084860, dated 09 / 19 / 2025, page 23 / 73 12 / 24 a controller 202 installed on the combine harvester 10 and / or on the implement (e.g., platform 32) and / or otherwise provided in operational association therewith. In general, the controller 202 of the described system 200 may correspond to any suitable processor-based device (or devices), such as a computing device or any combination of computing devices. Therefore, in various embodiments, the controller 202 may include one or more processors 206 and associated memory device (or associated memory devices) 208 configured to perform a variety of computer-implemented functions.As used in this document, the term "processor" refers not only to integrated circuits referred to in the art as being included in a computer, but also to a controller, a microcontroller, a microcomputer, a programmable logic controller (PLC), an application-specific integrated circuit, and other programmable circuits. Additionally, the memory device (or devices) 208 of the controller 202 may generally comprise the memory element (or elements) which includes, but is not limited to, a computer-readable medium (e.g., random access memory (RAM)), a computer-readable non-volatile medium (e.g., flash memory), a compact read-only memory disk (CD-ROM), an optical-magnetic disk (MOD), a digital versatile disk (DVD), and / or other suitable memory elements.Such memory device (or memory devices) 208 can generally be configured to store suitable computer-readable instructions which, when implemented by the processor (or processors) 206, configure the controller 202 to perform various computer-implemented functions, such as one or more aspects of a method 400 for controlling the height of the implement described below with reference to Figure 4.

[030] Additionally, controller 202 may also include several other Petition 870250084860, dated 09 / 19 / 2025, page 24 / 73 13 / 24 suitable components, such as a communications circuit or module, a network interface, one or more input / output channels, a control / data bus and / or the like, to enable the controller 202 to be communicatively coupled to any of the various other system components described herein. In some embodiments, the controller 202 may be configured to monitor and / or control the engine 210 and the transmission 212 of the combine harvester 10.

[031] Referring again to Figure 3, the controller 202 can generally be configured to control the operation of one or more components of the combine harvester 10. For example, in several embodiments, the controller 202 can be configured to control the operation of one or more components that regulate the height of the platform 32 relative to the ground 19. For example, the controller 202 can be communicatively coupled to one or more control valves 218 configured to regulate the supply of fluid (e.g., air or hydraulic fluid) to one or more corresponding actuators 220. In some embodiments, the actuators 220 may correspond to the height control cylinder 101, first tilt cylinder 102, and / or second tilt cylinder 104. The control valve (or valves) 218 ​​may correspond to one or more valves associated with cylinder (or cylinders) 101, 102, 104.

[032] Furthermore, as shown in the illustrated embodiment, the vehicle controller 202 can be communicatively coupled to a user interface 222 of the combine harvester 10. In general, the user interface 222 can correspond to any suitable input device (or devices) configured to allow the operator to provide operator inputs to the vehicle controller 202, such as a touch screen display, a keyboard, joystick, buttons, grips, switches, and / or combinations thereof located within the combine harvester cab 22. The operator can provide various inputs to the system 200 through the user interface 222. In one embodiment, suitable operator inputs may include, however, Petition 870250084860, dated 09 / 19 / 2025, page 25 / 73 14 / 24 without limitation, a target height for the implement, a crop type and / or characteristic indicative of a suitable target platform height, and / or any other parameter associated with implement height control.

[033] Additionally, the controller 202 can also be communicatively coupled to the various sensors associated with the platform 32. For example, as shown in Figure 3, the controller 202 can be coupled to one or more platform height sensors 224 configured to monitor the height of the platform 32 relative to the ground 19. In one embodiment, the platform height sensor (or sensors) 224 can correspond to one or more of the one or more height sensors 116, 118, 119 configured to monitor local distance (or distances) or defined height (or heights) 120 between the platform 32 and the ground 19.

[034] Now with reference to Figure 4, a flowchart of an embodiment of a method 400 for calibrating a height control system for an implement of an agricultural work vehicle is illustrated according to aspects of the present matter; Although Figure 4 depicts steps performed in a particular order for purposes of illustration and discussion, the methods discussed in the present document are not limited to any particular order or arrangement. A person skilled in the art, who uses the disclosures provided in the present document, will recognize that various steps of the methods disclosed in the present document may be omitted, rearranged, combined and / or adapted in various ways without departing from the scope of the present disclosure. Furthermore, method 400 will generally be described in the present document with reference to the combine harvester 10 and the platform 32 shown in Figure 1, as well as the various system components shown in Figure 3.However, it should be verified that the disclosed method 400 can be implemented to control the height of any suitable agricultural implement associated with a work vehicle that has any other suitable configuration and can be used in connection with any system that has any suitable system configuration. Petition 870250084860, dated 09 / 19 / 2025, page 26 / 73 15 / 24

[035] With reference to Figure 4, method 400 may include, in (402), providing an input signal to the height control system 200 (e.g., controller 202) to adjust a height 120 of the implement (e.g., platform 32) relative to the ground surface 19. The input signal may include a signal that commands the controller 202 to increase or decrease the height 120 of the platform 32 by a predetermined distance. For example, the input signal may include a step input signal, a ramp input signal, or other suitable input signal that causes the platform 32 to be moved from a first height relative to the ground surface 19 to a second, different height relative to the ground surface 19. In some implementations, the input signal may include a repetitive pattern, such as a sinusoidal pattern.

[036] Method 400 may include, in (404), monitoring the height of the implement (e.g., platform 32) relative to the ground surface 19. For example, controller 202 may receive signals from platform height sensor(s) 224 (e.g., height sensors 116, 118, 119 configured to monitor local distance(s) or height(s) 120 defined between platform 32 and the ground 19). Controller 202 may be configured to receive signals from height sensor(2) 224 and convert the signals into a measurement.

[037] In some implementations, the input signal can be provided to the height control system 200 and / or the height 120 of the implement (e.g., platform 32) relative to the ground surface 19 can be monitored while the agricultural work vehicle 10 is stationary. For example, method 400 can be performed on a promontory or area adjacent to a field where an agricultural operation (e.g., harvesting) is to be performed. Method 400 can be performed after changing the implement on the work vehicle or otherwise adjusting the configuration or settings of the work vehicle or height control system 200. In general, method 400 is performed while the vehicle 10 is stationary. In Petition 870250084860, dated 09 / 19 / 2025, page 27 / 73 16 / 24 However, in alternative embodiments, method 400 can be performed while vehicle 10 is in motion.

[038] Method 400 may include, in (406), adjusting (e.g., increasing) at least one gain of the height control system (e.g., controller 202). Exemplary gains that may be adjusted (e.g., increased) include a proportional signal gain associated with a proportional signal, an integral signal gain associated with an integral signal, and a derivative signal gain associated with a derivative signal of the height control system 200 (e.g., controller 202). As an example, the proportional signal gain may be increased while the integral and / or derivative signal gains are held constant (e.g., are set to zero). As further examples, the integral and / or derivative signal gains may be increased, and / or the proportional signal gain may be held constant (e.g., set to zero).

[039] Method 400 may include, in (408), determining a maximum stability gain of the height control system 200 based on the adjusted gain and the monitored height. The maximum stability gain may correspond to a stability point of the height control system 200 at which the height control system 200 transitions from stable to unstable, for example as described below with reference to Figures 5 and 6. In some embodiments, the height control system 200 may automatically increase the gain (or gains) of the height control system 200 and automatically determine when the maximum stability gain has been achieved, for example, by analyzing the time-varying implement height (for example, as described below with reference to Figures 5 and 6). In other embodiments, however, the operator may manually control one or more aspects of the calibration procedure.For example, the operator can observe the procedure and perform an input action when they observe that maximum stability gain has been achieved. This approach can allow the operator... Petition 870250084860, dated 09 / 19 / 2025, page 28 / 73 17 / 24 adjust system performance.

[040] For example, the operator can cause the calibration procedure to result in slightly lower gains for a slightly more stable and less responsive response. The operator can indicate that the maximum stability gain was achieved at a slightly lower gain level (e.g., earlier in the process of increasing the gain (or gains) until the maximum stability gain is achieved). This can allow the operator to calibrate the 200 height control system to be slightly more stable and less responsive or aggressive (e.g., slower). Conversely, the operator can indicate that the maximum stability gain was achieved at a gain closer to the actual maximum stability gain, resulting in the 200 height control system being more responsive or aggressive (e.g., faster) but less stable.

[041] Method 400 may include, in (410), defining the gain (or gains) of the height control system 200 based on the maximum stability gain. In some implementations, a period of oscillation of the height control system 200 at the maximum stability gain may be measured and / or stored, for example, as described below with reference to Figure 6. The gain (or gains) of the height control system 200 may be calculated based on the maximum stability gain. For example, the gain (or gains) of the height control system 200 may be queried and / or calculated using a lookup table based on the maximum stability gain. For example, Table 1 shows values ​​for proportional signal gain, Kp, integral signal gain, Ki, and derivative signal gain, Kd, ​​based on the maximum stability gain, Kms, and oscillation period, Tu, at the maximum stability gain.

[042] In some implementations, the gain (or gains) of the height control system 200 can be iteratively increased to determine the maximum stability gain. For example, step input signals can be provided. Petition 870250084860, dated 09 / 19 / 2025, page 29 / 73 18 / 24 iteratively to the height control system 200 and the gain (or gains) of the height control system 200 can be iteratively increased simultaneously. For example, a first input signal can be provided while the gain (or gains) (e.g., proportional signal gain) of the height control system 200 is set to a first gain value or values. The height 120 of the implement (e.g., platform 32) can be monitored as the height control system 200 adjusts the height 120 of platform 32 in response to the first input signal. The gain (or gains) of the height control system 200 can be increased to a second gain value or values. A second input signal can be provided while the gain (or gains) of the height control system 200 is at the second gain value (or values).The implement height 120 (e.g., platform 32) can be monitored again as the height control system 200 adjusts the height 120 of platform 32 in response to the second input signal. This process can be repeated until the gain (or gains) of the height control system 200 is approximately equal to the maximum stability gain (or gains) of the height control system. For example, the proportional signal gain can be increased until maximum stability is achieved while other gains are set to zero. At this point, the current gain (or gains) of the height control system 200 can be stored in memory 208 of the height control system 200 and / or communicated for storage on another non-transient computer-readable media.

[043] In several embodiments, the 200 height control system can be configured as a PID controller in which one or more of the PID controller gains is determined based on the maximum stability gain of the 200 height control system. The following equation shows the output signal, u(t), of a PID controller according to aspects of the present disclosure, where e(t) represents an implement height error as a function of time, t; and Kp, Ki, and Petition 870250084860, dated 09 / 19 / 2025, p. 30 / 73 19 / 24 Kd represent the respective constant gains for each of the proportional, integral, and derivative signal components: u(t) = Kpe(t) + K fe(t)dt + Kdd^(1)

[044] Implement height error is a difference between a monitored implement height and an input signal that instructs the PID controller circuit to set the implement height to a specific height. In other implementations, the controller may be a proportional (P) or proportional-integral (PI) or proportional-derivative (PD) controller. In other words, one or more of the proportional gain, integral gain, and / or derivative gain may be set equal to zero.

[045] Figure 5 provides a simplified example plot 500 of an input signal 502 and a first monitored implement height 504 for a first gain that is less than the maximum stability gain and a second monitored implement height 506 for a second gain that is greater than the maximum stability gain. The input signal 502 may include a slope from a first implement height 508 to a second implement height 510. In response to the input signal 502, the first monitored implement height 504 overshoots the second implement height 510 and oscillates around the second implement height 510. Since the first gain is less than the maximum stability gain, the first monitored height 506 eventually converges at the second implement height 510 (illustrated by dashed lines 512).

[046] Conversely, the second implement height 506 corresponds to a second gain that is greater than the maximum stability gain. Thus, oscillations of the second implement height 506 increase in magnitude over time (illustrated by dashed lines 514), resulting in instability of the height control system 200. In other words, the second implement height 506 diverges, illustrating that the height control system 200 is unstable. Such instability can cause damage to the height control system 200, for example, Petition 870250084860, dated 09 / 19 / 2025, page 31 / 73 20 / 24 damaging the actuators used to control the implement height.

[047] Figure 6 provides a simplified example plot 600 of an input signal 602 and a monitored third implement height 604 for a third gain that is approximately equal to the maximum stability gain. The input signal 502 may include a slope from a first implement height 608 to a second implement height 610. As illustrated, the monitored third implement height 604 may oscillate around the second implement height 610. The monitored third implement height 604, however, neither converges nor diverges. Instead, as illustrated by the dashed lines 612, the monitored third implement height 604 may oscillate in an immediate state condition (e.g., as a sinusoidal signal).

[048] A period of oscillation 616 of the monitored third implement height 604 can be determined by timing the oscillations (e.g., peak-to-peak). As indicated above, the gain (or gains) of the control system 200 can be increased to approximately equal to the maximum stability gain (e.g., equal to the third gain). The gain and oscillation period 616 can be stored. The operating gain (or gains) of the control system 200 can be defined based on the third gain.

[049] Aspects of the present disclosure are also directed to the height control system 200 which has been calibrated in accordance with aspects of the present disclosure. The height control system 200 can be configured to adjust the implement height using a PI or PID circuit that has one or more gains determined based on the maximum stability gain.

[050] Additionally, the 200 height control system can be configured to adjust the implement angle relative to the ground (e.g., side tilt and / or front / rear tilt) to account for ground unevenness. By Petition 870250084860, dated 09 / 19 / 2025, page 32 / 73 21 / 24 For example, the height control system 200 can be configured to adjust the implement height (e.g., platform 32) based on the height sensor(s) inputs 116, 118, 119. As indicated above, in some embodiments, the tilt cylinders 102, 104 may have the capability to adjust the angle of the combine harvester platform 32. For example, the controller 202 of the height control system 200 can be configured to adjust the local height(s) 120 measured at the center 110 of the platform 32, using the height control cylinder 101. Additionally, in some embodiments, the controller 202 can be configured to adjust the local height(s) 120 of the platform 32 at each end 106, 108 of the platform 32 using the tilt cylinders 102, 104.Furthermore, in some embodiments, the controller 202 can be configured to perform discrete or linked control circuits for each of the local heights 120 of the platform 32 using any suitable technique or combination of techniques described herein to adjust the lateral tilt and / or forward / backward tilt of the platform 32. For example, distinct respective gains for the discrete control circuits can be determined using the techniques described herein.

[051] The maximum stability gain of the 200 height control system may vary depending on the system properties and dynamics, which may include implement height (e.g., platform 32), implement center of gravity, and / or other implement, combine 10, or 200 height control system characteristics. Thus, the gain (or gains) that is determined based on the maximum stability gain may similarly vary based on implement characteristics, among other variables.

[052] In some embodiments, the 200 height control system can be configured to extrapolate appropriate gains to a replacement implement, for example, based on the height, center of gravity, etc. of the original implement and the Petition 870250084860, dated 09 / 19 / 2025, page 33 / 73 22 / 24 height, center of gravity, etc. of the replacement implement. The operator can perform the calibration procedure with the first original implement connected to the work vehicle. Subsequently, if the operator wishes to switch from the original implement to a replacement implement, the operator can avoid performing some or all steps of the calibration procedure again for the replacement implement. Instead, the operator can enter properties (e.g., weight, center of gravity, etc.) of the original implement and properties of the replacement implement. Alternatively, the operator can enter model information about one or both implements, and the 200 height control system can determine the relevant properties of the implement (or implements), for example from a lookup table, via an internet interface, etc.The 200 height control system can extrapolate the appropriate gain (or gains) to replacement implements based on their characteristics so that the replacement implement can be used without performing a completely new calibration procedure for the replacement implement.

[053] It should be understood that, in various embodiments, the steps of method 300 are performed by controller 202 by loading and executing code or software instructions that are tangibly stored on tangible computer-readable media, such as magnetic media, for example, a computer hard disk, optical media, for example, an optical disc, solid-state memory, for example, flash memory, or other storage media known in the art. Thus, in various embodiments, any of the functionalities performed by controller 202 described herein, such as method 300, are implemented in code or software instructions that are tangibly stored on tangible computer-readable media. Controller 202 loads the code or software instructions through a direct interface with the media. Petition 870250084860, dated 09 / 19 / 2025, page 34 / 73 23 / 24 computer-readable or via a wired and / or wireless network. By loading and executing such code or software instructions by controller 202, controller 202 can perform any of the controller 202 functionalities described herein, including any steps of method 300 described herein.

[054] The term software code or code used in this document refers to any instructions or set of instructions that influence the operation of a computer or controller. These may exist in a computer-executable form, such as machine code, which is the group 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 in this document, the term "software code" or "code" also includes any human-understandable computer instructions or group of instructions, for example, a script, that can be executed in real time with the aid of an interpreter run by a computer's central processing unit or by a controller.

[055] This written description uses examples to disclose the invention, including the improved manner, and also to enable any person skilled in the art to practice the invention, including creating and using any devices or systems and carrying out any methods incorporated therein. The patentable scope of the invention is defined by the claims and may include other examples that may have occurred to persons skilled in the art. Such other examples are intended to be covered by the scope of the claims if they include structural elements that are not different from the literal language of the claims or if they include structural elements Petition 870250084860, dated 09 / 19 / 2025, p. 35 / 73 24 / 24 equivalents with non-substantial differences from the literal language of the claims. Petition 870250084860, dated 09 / 19 / 2025, p. 36 / 73

Claims

1 / 5 CLAIMS 1. Method (400) for calibrating a height control system (200) for an implement (32) of an agricultural work vehicle (10), wherein the method (400) comprises: providing, with one or more computing devices (202), an input signal to the height control system (200) to adjust a height (120) of the implement (32) relative to the ground surface (19); monitoring, with one or more computing devices (202), the height (120) of the implement (32) relative to the ground surface (19); and adjusting, with one or more computing devices (202), at least one gain of the height control system (200);the method (400) being CHARACTERIZED by determining, with one or more computing devices (202), a maximum stability gain of the height control system (200) based on at least one gain and the monitored height (120), wherein the maximum stability gain corresponds to a stability point of the height control system (200) at which the height control system (200) transitions from stable to unstable; and defining, with one or more computing devices (202), at least one gain of the height control system (200) based on the maximum stability gain, wherein providing the input signal to the height control system (200) comprises iteratively providing step input signals to the height control system (200);adjusting at least one gain of the height control system (200) comprises iteratively increasing at least one gain of the height control system (200) simultaneously with the provision of step input signals to the height control system (200); Petition 870250084860, dated 09 / 19 / 2025, page 37 / 73 2 / 5 iteratively increasing at least one gain of the height control system (200) simultaneously with the provision of step input signals to the height control system (200) comprises increasing at least one gain of the height control system (200) until at least one gain of the height control system (200) is equal to the maximum stability gain of the height control system (200);and determine the maximum stability gain of the height control system (200) based on at least one gain comprises storing, on a non-transient computer-readable medium (208), at least one gain when at least one gain is equal to the maximum stability gain.; 2. Method (400), according to claim 1, CHARACTERIZED in that the input signal is provided to the height control system (200) and the height (120) of the implement (32) relative to the ground surface (19) is monitored while the agricultural work vehicle (10) is stationary.

3. Method (400), according to any of the preceding claims, CHARACTERIZED in that providing the input signal to the height control system (200) comprises providing a step input signal to the height control system (200).

4. Method (400), according to any of the preceding claims, CHARACTERIZED in that adjusting at least one gain of the height control system (200) comprises setting an integral signal gain and a derivative signal gain equal to zero and increasing a proportional signal gain.

5. Method (400), according to any of the preceding claims, CHARACTERIZED in that it further comprises determining an oscillation period of the height control system (200) for maximum stability gain.

6. Method (400), according to claim 5, CHARACTERIZED by Petition 870250084860, dated 09 / 19 / 2025, page 38 / 73 3 / 5 fact that determining the oscillation period of the height control system (200) for maximum stability gain comprises measuring a peak-to-peak time interval (616) of the monitored height of the implement (32) relative to the ground surface (19) when the height control system (200) is set at maximum stability gain.

7. Method (400), according to claim 6, CHARACTERIZED in that adjusting at least one gain of the height control system (200) based on the determined maximum stability gain comprises adjusting at least one gain of the height control system (200) based on each of the determined maximum stability gain and the determined oscillation period (616) of the height control system (200) for the maximum stability gain.

8. Method (400), according to any of the preceding claims, CHARACTERIZED in that adjusting at least one gain comprises adjusting each of a proportional signal gain, an integral signal gain and a derived signal gain of the height control system (200) based on the determined maximum stability gain.

9. Height control system (200) for an implement (32) of an agricultural work vehicle (10), wherein the height control system (200) comprises an implement (32), an implement height sensor (224) configured to detect a height (120) of the implement (32) relative to a ground surface (19), wherein the height control system (200) is CHARACTERIZED in that: an implement controller (202) is communicatively coupled to the implement height sensor (224), wherein the implement controller (202) includes a processor (206) and associated memory (208), wherein the memory (208) stores instructions which, when executed by the processor (206), configure the implement controller (202) to perform operations which include: Petition 870250084860, dated 19 / 09 / 2025, page. 39 / 73 4 / 5 provide an input signal to the height control system (200) to adjust the height (120) of the implement (32) relative to the ground surface (19);monitor the height (120) of the implement (32) relative to the ground surface (19) based on signals received from the implement height sensor (224); adjust at least one gain of the height control system (200); determine a maximum stability gain of the height control system (200) based on at least one gain and the monitored height (120), wherein the maximum stability gain corresponds to a stability point of the height control system (200) at which the height control system (200) transitions from stable to unstable; and define at least one gain of the height control system (200) based on the maximum stability gain, provide the input signal to the height control system (200) comprising iteratively providing step input signals to the height control system (200);adjusting at least one gain of the height control system (200) comprises iteratively increasing at least one gain of the height control system (200) simultaneously with the supply of step input signals to the height control system (200); iteratively increasing at least one gain of the height control system (200) simultaneously with the supply of step input signals to the height control system (200) comprises increasing at least one gain of the height control system (200) until at least one gain of the height control system (200) is equal to the maximum stability gain of the height control system (200);and determine the maximum stability gain of the height control system (200) based on at least one gain comprises storing, on a non-transient computer-readable medium (208), at least one gain when at least one gain is equal to the maximum stability gain.

10. System according to claim 9, CHARACTERIZED in that the input signal is provided to the height control system (200) and the height of the implement (32) relative to the ground surface (19) is monitored while the agricultural work vehicle (10) is stationary.

11. System, according to any one of claims 9 or 10, CHARACTERIZED in that providing the input signal to the height control system (200) comprises providing a step input signal to the height control system (200). Petition 870250084860, dated 09 / 19 / 2025, p. 41 / 73;

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