System and method for header height control

Abstract

A harvesting header including a cutter bar and a gauge wheel configured to vary a crop cut height in a field. The gauge wheel is operable to move the cutter bar relative to the ground to adjust the cut height. The harvesting header may further include a control system, a ground position sensor, and a crop height sensor configured to measure a height of a crop canopy relative to the ground. The control system is further configured to determine a slope of the ground in front of the harvesting header, to predict a desired future height of the cutter bar based on the slope of the ground and the height of the crop canopy, and to move the gauge wheel to match the height of the cutter bar to the desired future height.

Description

Docket Xe: 159031-00939SYSTEM AND METHOD FOR HEADER HEIGHT CONTROLBACKGROUND

[0001] Crop harvesters cut and collect a variety of crop from a field and generally include a harvester, or tractor, and a header mounted to the front of the harvester. The header includes a cutter bar assembly to cut crop material from the field, and a draper belt assembly positioned behind the cutter bar assembly to transport the crop material into a feeder house of the harvester. A variety of hydraulic cylinders may be used to adjust harvester components such as the height of the cutter bar assembly relative to the field by moving the header. For example, a contour wheel or gauge wheel cylinder may extend or retract contour wheels on the header to adjust the height of the cutter bar assembly when cutting above the ground. Similarly, a skid shoe cylinder may be provided to extend or retract skid shoes on the header to adjust the height of the cutter bar assembly when cutting close to the ground. A header tilt cylinder and / or a faceplate cylinder also may control the pitch of the header relative to the ground during the cutting action.

[0002] Some header designs, such as a flex header, may have header segments that can articulate and follow ground contours, and an operator may use the contour wheels or gauge wheels to control the height of a flex header while allowing it to follow the field topography, similar to when it is cutting on the ground. When determining appropriate cut height, an operator determines the length of stubble desired and adjusts the height of the contour wheels. When a change in cut height is required, the operator must adjust the contour wheels to set the cut height and thereby generate a constant stubble height throughout the field being worked.

[0003] During operation, some header configurations monitor the ground in order to determine the height of the cutter bar assembly above the ground, which may be used by an operator who desires to cut the crop a certain height above the ground for a desired stubble height. However, deciding on a desired stubble height can be as simple as selecting a constant value for the entire field, or as complicated as manually changing the cut height throughout the field depending on field topography, crop material density, or other factors. Oftentimes a high level of skill and experience are required to adjust stubble height manually, which may further require familiarity with each field in which the harvester operates as some fields may have differing elevations within a field boundary. Furthermore, if an operator desires to vary the stubble height within the same field, manual systems would require the operator to adjust the inputs on the fly during harvesting.Docket Xe: 159031-00939SUMMARY

[0004] In one aspect, a harvesting header is configured to vary a cut height in a field, the harvesting header includes a header frame, a cutter bar assembly coupled to the header frame for cutting crops at a cut height, a gauge wheel assembly coupled to the header frame and operable to move the cutter bar assembly relative to the ground to adjust the cut height, a ground position sensor coupled to the header frame and configured to measure a height of the cutter bar above the ground, and a crop height sensor coupled to the header frame and arranged in front of the cutter bar, wherein the crop height sensor is configured to measure a height of a crop canopy relative to the ground. The harvesting header further includes a control system in communication with the crop height sensor and the ground position sensor and operable to control the cut height during operation of the harvesting header. The control system is configured to move the gauge wheel assembly to control the cut height based on the height of the crop canopy. The control system is further configured to determine a slope of the ground in front of the header frame, predict a desired future height of the cutter bar based on the slope of the ground and the height of the crop canopy, and move the gauge wheel assembly to match the height of the cutter bar to the desired future height.

[0005] In another aspect, a method for operating a control system for a harvesting header to control a cut height during operation of the harvesting header. The harvesting header includes a header frame, a cutter bar assembly coupled to the header frame for cutting crops at a cut height, a gauge wheel assembly coupled to the header frame and operable to move the cutter bar assembly relative to the ground to adjust the cut height, a ground position sensor coupled to the header frame and configured to measure a height of the cutter bar above the ground, and a crop height sensor coupled to the header frame and arranged in front of the cutter bar and configured to measure a height of a crop canopy relative to the ground. The control system is in communication with the crop height sensor and the ground position sensor. The method includes determining the cutter bar height with the ground position sensor, determining the height of the crop canopy relative to the ground with the crop height sensor, creating a header plane based on the cutter bar height and the height of the crop canopy, determining a difference between the header plane and a theoretical base plane and correcting the base plane based on the difference, and moving the gauge wheel assembly to control the cut height based on the height of the crop canopy.Docket Xe: 159031-00939

[0006] Any of the above aspects can be combined in full or in part. Any features of the above aspects can be combined in full or in part. Any of the above implementations for any aspect can be combined with any other aspect. Any of the above implementations can be combined with any other implementation whether for the same aspect or a different aspect.BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Advantages of the present disclosure will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings.

[0008] FIG. 1 is a schematic side view of a harvesting header attached to a harvester on a ground surface and showing a measured header plane and an estimated header plane based on readings from a crop sensor.

[0009] FIG. 2 is a schematic rear view of the header and harvester of FIG. 1 showing a single header plane based on the crop sensor readings.

[0010] FIG. 3 is a schematic rear view of the header and harvester of FIG. 1 showing multiple header planes based on the crop sensor readings.

[0011] FIG. 4 is a schematic top view of the header and harvester of FIG. 1 showing a single header plane based on the crop sensor readings.

[0012] FIG. 5 is a schematic top view of the header and harvester of FIG. 1 showing multiple header planes based on the crop sensor readings.

[0013] FIG. 6 is a schematic side view of the header and harvester of FIG. 1 showing the header plane overshooting and undershooting the ground surface.

[0014] FIG. 7 is a schematic side view of the header and harvester of FIG. 1 showing multiple header planes smoothing the header plane.

[0015] FIG. 8 is a schematic side view of the header and harvester of FIG. 1 harvesting crops growing on a ground surface and showing a desired cut height path and an actual cut height path.

[0016] FIG. 9 is a diagrammatic side view of the header of FIG. 1 showing operational variables relative to the header geometry.

[0017] FIG. 10 is a flowchart of a method for controlling the header height.DETAILED DESCRIPTION

[0018] FIG. 1 illustrates a combine harvester 50 e.g., combine, which includes a header 100 mounted on a feeder house 52. The header 100 includes a header frame 102 and a cutter barDocket Xe: 159031-00939assembly 106 (FIG. 9) operatively extending across a front portion of the header 100 to cut crop material from the field. A draper assembly typically is positioned behind the cutter bar assembly 106 to transport the crop material into the feeder house 52 of the harvester 50.

[0019] As illustrated herein, the header 100 is supported close to the ground 56 such that the height of the cutter bar assembly 106 can be varied to cut crop close to the ground 56 and to increase the cut height. In this configuration, a contour wheel or gauge wheel 108 is pivotably connected to the header 100 for ground following contact. The gauge wheel 108 includes a wheel 110 rotatably connected to a pivot arm 112. The pivot arm 112 is pivotably connected to the header 100 and a hydraulic gauge wheel cylinder (not shown) may be used to extend and retract the gauge wheel 108. In the extended position, the gauge wheel 108 follows the ground 56 and supports the header 100 when cutting at a set cut height above the ground 56. Extension or retraction of the gauge wheel 108 raises and lowers the cut height. The leading edge of the cutter bar assembly 106 includes a cutter bar 114 (FIG. 9) to perform cutting of the crop, wherein the cut portion of the crop moves through the header 100 to the feeder house 52, while the remaining portion defines stubble that remains in the field after harvesting. Generally, the cut height corresponds to the stubble height SH referenced in FIGS. 8 and 9. The header 100 may also be adjustable to adjust the pitch thereof.

[0020] Referring further to FIG. 1 , one or more crop pick-up reels 118 are positioned generally above the front portion of the header 100 for engaging the crops to be harvested. The cutter bar assembly 106 operatively extends across the front portion of the header frame 102 between the ends thereof for cutting the crops to be harvested as referenced above. During harvesting, the crop pick-up reels 118 are typically positioned close to the cutter bar assembly 106 without contacting the cutter bar assembly 106 to facilitate optimal harvesting efficiency of the header 100.

[0021] In some embodiments, the cutter bar assembly 106 is correspondingly flexible with center and side wing sections of the header 100 for contouring to the field. One such configuration of the cutter bar assembly 106 and the header 100 is described in U.S. Patent No. 10,462,968, the disclosure of which is hereby incorporated by reference in its entirety.

[0022] Referring to FIGS. 2-5, the header 100 includes a plurality of reel support arms 120 disposed adjacent to each end of the crop pick-up reels 118 for supporting these crop pick-up reels 118 on the header frame 102. Each reel 118 is rotatably supported by the reel support arms 120. The reel support arms 120 are pivotable on the header frame 102 upwardly and downwardly via aDocket Xe: 159031-00939hydraulic system to vertically position the crop pick-up reels 118 relative to the cutter bar assembly 106 for optimally engaging the crops, as is known in the art. It is to be appreciated that the header 100 may ultimately include any number or arrangement of the reel support arms 120 and the crop pick-up reels 118 to correspond to the number of sections on the header 100 without varying the scope of the disclosure.

[0023] The header 100 may be used to cut crops in an auto header height control mode ("AHHC"), which uses a sensor (e.g., a wheel, dongle, lever position, etc.) to determine the height of the header 100 relative to the ground 56 and adjusts the height thereof to achieve that height target and thereby adjust the cut height of the cutter bar assembly 106 and the resultant stubble height SH. The header 100 has a control system 116 that includes monitoring devices, a processor, memory and one or more control units to adjust the cut height. The monitoring devices may include position sensors for the header and other sensors. FIG. 8 generally illustrates the header 100 operated according to this operating mode wherein the stubble height is identified as SH, wherein the stubble height is constant throughout the field as a result of the operator preselecting a constant stubble height, and the cutter bar assembly 106 is operated to cut crops at this predefined stubble height.

[0024] In this operating configuration of FIG. 8, the height of the cutter bar assembly 106 (FIG. 9) can be monitored relative to ground and the operator can input the cut height so as to generate a fixed stubble height SH. The crop canopy height is diagrammatically shown by the dashed line CH. Realistically in a field, the actual crop height CH is generally similar throughout the field. However, this may not be true for all field areas wherein the canopy or crop height CH may be shorter and, in some cases, substantially shorter than the majority of the crop height. FIG.8 shows a depressed crop area designated with a crop height CHI. These aberrations in the crop height CHI can be caused by various environmental reasons during a growing season or different ground conditions in the field. In the operating mode depicted in FIG. 8, the shorter crop height CHI may actually fall below the set stubble height SH. As a result, all or some of the harvestable top portion of the crop is missed. While an operator might attempt to monitor the canopy height as the harvester 50 is moving, it can be difficult for the operator to judge whether the crop height CHI looks lower than the set cut height and difficult to manually adjust the cut height as the harvester 50 operates. As such, manual adjustment of the cut height based on ground sensing during use may be difficult and undesirable and still may not avoid missing of harvestable crop.Docket Xe: 159031-00939

[0025] Referring to inventive operating modes of FIGS. 6-10, the improved header 100 and control system therefore is a header height control system 116 (shown schematically in FIG. 1) that allows a header 100 to control its cutting height off of the ground 56 automatically using an initial input by the operator for a target cut height resulting in a desired stubble height SH and then automatic adjustment in response to sensing of the crop height CH of the crops being harvested.

[0026] As seen in FIGS. 1-9, the header 100 includes one or more sensor support arms 122 with one or more sensors 124 attached to the header frame 102 that would reference or detect the distance CDP to the crop canopy CC and the distance GDP to the ground 56. Using the distance CDP to the crop canopy CC and the distance GDP to the ground 56, the control system can calculate the crop height CH. The ground 56 and crop or crop height CH may be sensed by a sensor 124 having a single sensor module or multiple sensing modules. The control system 116 is operated to vary the position of the gauge wheels 108 and the cutter bar assembly 106 supported thereby to control the position of the cutter bar assembly 106 and cut height off of the ground 56 relative to the desired input from the operator. The control system 116 is operable in at least one of two possible operating modes wherein possible inputs would be height of the header 100 or the cutter bar assembly 106 off of the ground 56 or its height below the crop height CH.

[0027] With the use of appropriate sensors 124, the control system 116 can be utilized to automatically adjust the gauge wheel position relative to the crop canopy CC as well as the ground 56. The sensors 124 may comprise radar sensors that continuously or intermittently sense and monitor the crop height CH and ground position, which are typically sensed and monitored simultaneously. The sensors 124 also may be radar, LiDAR, or ultrasonic sensors or other appropriate sensors or sensing systems such as a vision system, which can sense or detect the ground elevation and crop height CH even when crops are fully developed. As shown in FIGS. 2-5, the header 100 includes four sensors 124, with each sensor 124 supported on a corresponding sensor support arm 122. Each of the sensors 124 has an exemplary field of view 126, which illustrates the approximate region area that the respective sensor 124 is measuring. The sensors 124 are spaced along the width of the header 100 to measure the distance to the ground GDP and to the crop canopy CDP at four positions along the header 100.

[0028] As mentioned above, the header 100 shown here is flexible along the width to facilitate following the ground 56 when the height of the ground 56 varies across the width of the header 100. Measuring the distance to the ground and to the crop canopy CC at one or more positionsDocket Xe: 159031-00939along the header 100 allows the control system 116 to adjust the left and right sides of the header 100 independently of one another in accordance with ground and crop conditions. Said differently, the gauge wheel assembly 108 can be operated to raise and lower one of the side wings of the header 100 to a desired cutter bar height to accommodate a crest or depression in the field or variations in crop height CH during operation. As will be discussed below, the control system 116 is capable of calculating an estimated ground plane EGP using measurements combined from each of the sensors 124, such as shown in FIGS. 2 and 4. Additionally, the control system 116 is capable of calculating separate estimated ground planes EGP for each of the four sensors 124, such as shown in FIGS. 3 and 5. A single estimated ground plane EGP may be used when the header 100 is less wide, when the header 100 is not flexible along its width, or when the flex system is disabled.

[0029] In one advantageous aspect, the control system 116 incorporates the ground following benefits resulting from adjustable gauge wheels 108 and also includes additional control options for the operator. By measuring the height of the header 100 or the cutter bar assembly 106 relative to both the ground 56 and the canopy or crop height CH, the operator may have the option to set the header and cutter bar heights relative to the ground position or relative to the crop height CH. This allows the operator to maintain stubble height SH at a desired height or allow the operator to maximize the stubble height SH based on crop height CH.

[0030] In a further beneficial aspect, the operator could also set a target cut height and the resultant stubble height SH associated therewith, but if the crop height CH falls below the target cut height, the header 100 will automatically adjust the cut height below the desired target cut height. As a result, no harvestable crop is missed, and an operator does not need to attempt to monitor the crop height CH and judge whether the crop height CH appears to be lower than the cut height.

[0031] In another aspect, the operating mode where the cut height is determined based upon crop height CH can be operated so that the stubble height can also be maximized. In some conditions, an operator or field manager may prefer to maximize stubble height SH for various environmental programs and soil conservation strategies.

[0032] The control system 116 is operable in at least one of several operating modes, wherein possible inputs could be the height of the header 100 or the cutter bar assembly 106 off of the ground to generate a target cut height and constant stubble height SH and could be the height thereof below the canopy height as defined by a target intake fraction that governs the percentageDocket Xe: 159031-00939of canopy top that is harvested. With the use of appropriate sensors 124, the control system 116 can be utilized to automatically adjust the gauge wheel position relative to the crop canopy CC as well as the ground 56.

[0033] More particularly as to the first operating mode, the operator inputs a preferred stubble height SH that preferably is intended to remain constant as the field is harvested. However, the crop height CH is monitored during combine operation and when a depressed or shorter crop height CH is detected that falls below the set stubble height SH, the header 100 or the cutter bar assembly 106 is automatically lowered by the control system 116 so that a reduced or adjusted stubble height SH is applied that is at least as low as the shorter crop height CH. Preferably, the adjusted stubble height SH is able to maintain a minimum intake fraction that recovers the harvestable portion of the shorter crop. The adjusted stubble height SH may be a single value less than the reduced crop height CH or may be continuously variable or adjusted to react to further variations in the reduced crop height CH. In this operating mode, no harvestable crop is missed even when the crop height CH drops substantially or abruptly. This adjusted stubble height SH may even be lowered to ground level to ensure no harvestable crop is missed. Once an increase in the harvestable crop height CH is detected by the sensors 124, the control system 116 raises the cut height after the crop canopy CC is again detected by the sensors 124. Eventually, the target cut height is reached to leave the target stubble height SH.

[0034] As to the second operating mode, this operating mode provides a maximum stubble height relative to the canopy or crop height CH while still maximizing the amount of the crop that is desired to be removed or in other words, minimizing the intake fraction. In this second operating mode, the operator inputs a desired target intake fraction, and the cut height is determined relative to this target intake fraction. This may result in a variable stubble height SH. In this operating mode, the stubble height SH is defined in reference to the canopy or crop height CH and use of the target intake fraction. In this configuration, the stubble height may be defined by an intake fraction or in other words, the ratio of harvestable top portion of the crop relative to the total crop height CH being detected by the sensors 124 and monitored by the control system 116. For example, it may be desirable to harvest the top of the crop of some set quantity such as 25% of the total crop height CH. This percentage-based quantity is referenced as the intake fraction and may vary depending upon the type of crop and the amount of the crop that is harvestable. For example, it may be desirable to harvest the top 25% of wheat and the top 40% of canola. This intake fractionDocket Xe: 159031-00939may also be a desired height from canopy. For example, a cut of some value, such as a cut of 20 cm, may be removed from the crop canopy in standing crop, but if harvesting lodged or down crop, the harvester may cut on the ground and then return to 20 cm of removal when the harvester is back in standing crop.

[0035] The harvest percentage or intake fraction may continue to be used throughout the field. As long as the crop height CH is detected and monitored, the gauge wheels 108 can be automatically adjusted to maintain the desired maximum stubble height SH in areas of higher crop height CH and a reduced stubble height SH in areas of reduced or shorter crop height CH. The actual stubble height therefore can vary between full height stubble areas having desired maximum stubble height SH and shorter areas having a reduced stubble height SH.

[0036] In most cases, it is desirable to use a constant intake fraction or ratio of harvestable portion versus total crop height throughout the field. However, it is possible to vary the intake fraction, wherein the intake fraction may be set for full height crop and adjusted for shorter or stunted crop.

[0037] In addition to the above, the control system 116 may provide the operator with an adjustable parameter for how closely or aggressively the header 100 should attempt to follow the preferred stubble height SH. In other words, whether the control system 116 may favor a cut height that prevents the stubble height SH from exceeding the preferred stubble height SH or a cut height that prevents the stubble height SH from being less than the preferred stubble height SH. For example, in a high aggressiveness setting, the control system 116 may aggressively attempt to follow the preferred stubble height SH and prevent any stubble from being too tall. Alternatively, in a low aggressiveness setting, the control system 116 less aggressively attempts to follow the preferred stubble height SH and instead tries to prevent stubble from being too short, which may allow a greater variance for stubble that is taller than desired (i.e., harvests the crop less completely and may leave some unharvested crop). In a middle aggressiveness setting the cut height may be set using an average of the ground planes EGP determined by the control system 116, as is discussed below.

[0038] To operate the header 100 in these different operating modes, the header 100 may include adjustment mechanisms that may vary and adjust the geometry of the mechanisms on the header 100. FIG. 9 diagrammatically shows some of the different variables for the operating geometry. As shown in FIG. 9, the header 100 may use the sensors 124 on a sensor support armDocket Xe: 159031-00939122 to detect the crop canopy CC and the ground 56 to determine and monitor the crop height CH. The sensor support arms 122 are configured to extend forwardly of the reel 118 to detect the crop canopy CC and the ground 56 ahead of the harvester 50 as it travels over a field. The reel support arm 120 is typically adjustable such that the combine control system 116 may monitor the reel arm pitch. The sensor support arm 122 may be maintained parallel to the ground 56 so that the perpendicular ground distance GDP can be monitored as well as the perpendicular crop distance CDP. However, the sensor support arm 122 might not be parallel wherein this can optionally be corrected for in an algorithm implemented in the control system 116.

[0039] Since the cutter bar assembly 106 and the header 100 can be raised and lowered by the gauge wheels 108, the cutter bar 114 can be raised and lowered accordingly. As mentioned, the cutter bar assembly 106 and the header 100 may be formed as a single unit or from multiple articulating sections. The control system 116 may monitor the header pitch relative to a gravity reference plane as well as a vertical distance below the sensor 124 to the cutter bar 114. The control system 116 may also monitor the pitch of the combine / harvester 50 or cab thereof. Monitoring of these variables allows calculation of the stubble height SH. Further, the control system 116 may monitor the reel arm pitch and use the angle to calculate a reel arm pitch that determines the ground distance at this angle, which angles rearwardly of the perpendicular ground distance GDP.

[0040] In addition to the above, the control system 116 may be configured to determine a slope of the ground 56 over which the harvester 50 and header 100 are operated. The control system 116 estimates the estimated ground plane EGP using two points, such as a contact point Pl between the gauge wheel 108 and the ground 56, and the intersection point P2 between the ground 56 and a radar signal from one of the sensors 124. The slope of the estimated ground plane EGP is calculated relative to a level header 100 and the slope is further used to estimate the cut height. The cut height may further be refined or corrected for the direction of gravity using a sensor such as an inclinometer. When operating in the modes described above, the cut height is varied to adjust the stubble height SH according to the crop height CH of the crop canopy CC. For example, in this mode, as the harvester 50 is operated in a field the stubble height SH may increase as the crop height increases in order to maximize the stubble height SH without leaving behind harvestable portions of the crop. Said differently, the stubble height SH may increase as the crop height increases in order to cut the crop a predetermined distance below the crop canopy CC.Docket Xe: 159031-00939

[0041] When the control system 116 is operated in a constant stubble height SH mode, as the header 100 traverses a crest or valley in the ground, the height of the cutter bar 106 will lag behind the height of the header as determined by the horizontal distance CBH between the cutter bar 114 and the gauge wheel 108. Because the height of the cutter bar 114 is controlled by the gauge wheel 108, the cutter bar 114 is dictated by the contours of the ground below the gauge wheel 108 and not the contours of the ground below the cutter bar 114. For example, when the header 100 approaches a crest (i.e., an area of increasing elevation), the cutter bar 114 encounters the crest before the gauge wheel 108. As the header 100 continues, the crest rises below the cutter bar 114 and the stubble height SH decreases until the gauge wheel 108 encounters the crest, which begins to raise the header 100. Similarly, when the header 100 approaches the end of the crest, the ground below the cutter bar 114 begins to fall while the gauge wheel 108 is still on the crest, which causes the stubble height SH to increase until the gauge wheel 108 reaches the end of the crest allowing the header 100 to move downward.

[0042] One way to mitigate the lag of the cutter bar height relative to the gauge wheel 108 is to use the estimated ground plane EGP, as described above to adjust the height of the header 100. FIG. 6 shows a single estimated ground plane EGP determined by the sensors 124 that is projected forward from the sensors 124. As the header 100 traverses a crest or depression in the ground, the dashed line of the estimated ground plane EGP shows how a single point estimation of the ground plane causes the cutter bar 114 to overshoot 130 and undershoot 132 the desired stubble height SHI. Best shown in FIG. 8, for example, when the header 100 approaches a crest, the sensor 124 is measuring the perpendicular ground distance GDP, which decreases as the sensor 124 encounters the crest. In response to the perpendicular ground distance GDP decreasing the control system 116 operates the gauge wheel 108 to increase the height of the header 100. However, because the sensor 124 encounters the crest before the cutter bar 114, the height of the header 100, and the stubble height SH, begin to increase prior to the cutter bar 114 encountering the crest causing the stubble height SH to overshoot 130 the desired stubble height SHI. Similarly, as the header 100 approaches the end of the crest, the ground below the sensor 124 begins to fall while the cutter bar 114 is still above the crest, which causes the stubble height SH to decrease until the cutter bar 114 is past the crest causing the stubble height SH to undershoot 132 the desired stubble height SHI.Docket Xe: 159031-00939

[0043] One method of following the contours of the ground more closely is achieved by measuring the slope of the ground. More particularly, the control system 116 is configured to determine the slope of the ground between two points over which the header 100 is operating. By determining the slope of the ground (i.e., rate of height change), the control system 116 can determine height adjustments necessary to accommodate the height of the cutter bar 114 and avoid the effects of the lag associated with the horizontal distance CBH between the cutter bar 114 and the gauge wheel 108. Multiple ground planes EGP are shown in FIG. 7, which represent the ground planes determined using two points, as described below. In contrast to the single point estimated ground plane EGP1 (FIG. 6), the two point ground planes EGP2 more closely match the contours of the ground. By combining the slope of the ground plane with the current cut height, as measured by the position of the gauge wheel 108, the control system 116 can assess whether the gauge wheel 108 will need to raise or lower the header 100 to achieve a future desired height.

[0044] As mentioned above, the control system 116 determines the ground plane using the measurements of the ground position at two points. The first point used to determine the ground plane is the perpendicular ground measurement GDP between the sensor 124 and the ground. The second point used by the control system 116 to determine the ground plane is a second ground position, which may be determined by the position of the gauge wheel 108, and which is generally proportional to the stubble height SH. The stubble height SH may be measured by a ground position sensor (not shown) attached to the gauge wheel 108 and configured to determine the relative position of the wheel 110 and the header frame 102. Alternatively, the ground position sensor may be a distance sensor such as a radar sensor or an ultrasonic sensor. The control system 116 combines these measurements with predetermined geometric data about the header 100 to estimate the slope of the ground plane. More specifically, the geometric relationships between the positions of the sensors 124, the positions of the gauge wheel 108, the position of the cutter bar 114, and other datums on the header frame 102 are stored in the control system 116 and referenced when calculating the slope of the ground plane.

[0045] The control system 116 can further control the rate of height adjustment during operation. For example, if the harvester 50 is approaching the slope more quickly (i.e., the harvester is driving faster), the control system 116 will actuate the hydraulics controlling the gauge wheel 108 more quickly. In this way, the control system 116 can adjust the height of the header 100 with increased accuracy and precision. The rate of height adjustment can be calculated byDocket Xe: 159031-00939taking consecutive measurements of the slope of the ground plane and calculating a speed dependent slope based on the desired future height. For example, if the harvester 50 is approaching a relatively small slope while traveling through the field at a relatively fast speed, the speed dependent slope would be similar to the harvester 50 approaching a relatively large slope while traveling through the field at a relatively slow speed.

[0046] Using the measurements from the sensors 124, the control system 116 can utilize a nonlinear algorithmic system to predict the desired future height at which the height or position of the header 100 will need to be in order to accommodate the future position relative to the ground or crop. Said differently, the desired future height is a function of the measurements from the sensors 124 as well as operator inputs for harvesting preferences. The control system 116 takes into account the desired intake fraction or distance below the canopy that the operator desires to harvest, the canopy height CC, and the geometry of the header 100, and uses the non-linear algorithmic system to predict the desired future height in order to control the adjustment of the gauge wheels 108.

[0047] Referring to FIG. 10, a flow chart 200 showing an exemplary method for adjusting the height of the header 100 is shown. In a first step 202, the control system 116 creates the header plane based on the sensors 124 and the ground position sensor coupled to the header 100. In step 202, the header plane created by the control system 116 may include a header plane based on the sensors 124 coupled to the sensor support arms 122 and arranged ahead of and above the header frame 102, as well as the sensors associated with the gauge wheel 108 for measuring the stubble height SH.

[0048] Concurrently with the first step 202, the control system 116 performs a second step 204. In the second step 204, the control system 116 creates a harvester and header plane, which is based on geometry of the harvester 50 and the header 100. As described above, the geometry of the header 100 may include the geometric relationships between the positions of the sensors 124, the positions of the gauge wheel 108, the position of the cutter bar 114, and other datums on the header frame 102. Additionally, the geometry of the harvester 50 may include the position and relationships of the header 100 relative to the harvester 50, the wheels of the harvester 50, and a lifting mechanism between the harvester 50 and the header 100.

[0049] Subsequent to the first step 202 and the second step 204, the control system 116 performs a third step 206. In the third step 206, the control system 116 determines the differenceDocket Xe: 159031-00939between the header plane and a theoretical flat base plane. The difference between the header plane and a theoretical flat base plane is used to create a relative error measurement to correct a local plane beneath the header 100 and the sensors 124. Subsequent to the third step 206, the control system 116 performs a fourth step 208. In the fourth step 208 the control system calculates the angle or slope of the local plane beneath the header 100 based on the error measurement identified in the third step 206.

[0050] Subsequent to the fourth step 208, the control system 116 performs a fifth step 210. In the fifth step 210 the control system 116 calculates a rate of change for the angle of the local plane beneath the header 100. A positive rate of change of the angle of the local plane indicates the angle, or slope, is increasing, such as when the header 100 approaches the base of a raised area of ground. A negative rate of change of the angle of the local plane indicates the angle is decreasing, such as when the header 100 approaches the edge of a depression in the ground. Similarly, a positive rate of change of the angle of the local plane may indicate the header 100 is exiting a depression in the ground, and a negative rate of change may indicate the header 100 has passed the crest of a raised area of ground.

[0051] Following the fifth step 210, the control system 116 performs a sixth step 212. In the sixth step 212 the control system 116 adjusts the position or height of the header 100 based on the rate of change of the angle of the local plane using a rate based model projection. Said differently, the control system 116 adjusts the position of height of the header 100 at rate corresponding to the rate of change of the angle calculated in the fifth step 210. When the value of the rate of change of the angle is relatively low, the control system 116 adjusts the position of the header 100 at a relatively slow speed (i.e., the hydraulic system is operated at a low rate) and when the value of the rate of change of the angle is relatively high, the control system 116 adjusts the position of the header 100 at a relatively high speed (i.e., the hydraulic system is operated at a high rate).

[0052] Several instances have been discussed in the foregoing description. However, the aspects discussed herein are not intended to be exhaustive or limit the disclosure to any particular form. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects without departing from the scope of the disclosure. The terminology that has been used is intended to be in the nature of words of description rather than of limitation. Many modifications and variations are possible inDocket Xe: 159031-00939light of the above teachings and the disclosure may be practiced otherwise than as specifically described.

Claims

Docket Xe: 159031-00939CLAIMSWhat is claimed is:

1. A harvesting header configured to vary a cut height in a field, the harvesting header comprising:a header frame;a cutter bar assembly coupled to the header frame for cutting crops at a cut height;a gauge wheel assembly coupled to the header frame and operable to move the cutter bar assembly relative to the ground to adjust the cut height;a ground position sensor coupled to the header frame and configured to measure a height of the cutter bar above the ground;a crop height sensor coupled to the header frame and arranged in front of the cutter bar, wherein the crop height sensor is configured to measure a height of a crop canopy relative to the ground;a control system in communication with the crop height sensor and the ground position sensor and operable to control the cut height during operation of the harvesting header; wherein the control system is configured to move the gauge wheel assembly to control the cut height based on the height of the crop canopy; andwherein the control system is further configured to determine a slope of the ground in front of the header frame, predict a desired future height of the cutter bar based on the slope of the ground and the height of the crop canopy, and move the gauge wheel assembly to match the height of the cutter bar to the desired future height.

2. The harvesting header of claim 1, wherein the control system calculates a desired cut height based on a desired intake fraction chosen by an operator.

3. The harvesting header of claim 2, wherein the desired intake fraction is a ratio of a harvestable portion of a crop removed from a crop height relative to a total crop height.

4. The harvesting header of any of claims 1-3, wherein the control system calculates the desired future height of the cutter bar based on a desired stubble height chosen by an operator.Docket Xe: 159031-009395. The harvesting header of any of claims 1-4, wherein the crop height sensor is configured to measure a distance to the ground and a distance to the crop canopy, and wherein the height of the crop canopy is determined by subtracting the distance to the crop canopy from the distance to the ground.

6. The harvesting header of claim 5, wherein the slope of the ground in front of the header frame is determined based on the distance to the ground measured by the crop height sensor and predetermined geometric data about the harvesting header.

7. The harvesting header of claim 6, wherein the predetermined geometric data about the harvesting header includes geometric relationships between a position of the crop height sensor, a position of the cutter bar, and a position of the gauge wheel assembly.

8. The harvesting header of any of claims 5-7, wherein the crop height sensor is a radar sensor.

9. A method for operating a control system for a harvesting header to control a cut height during operation of the harvesting header, the harvesting header including a header frame, a cutter bar assembly coupled to the header frame for cutting crops at a cut height, a gauge wheel assembly coupled to the header frame and operable to move the cutter bar assembly relative to the ground to adjust the cut height, a ground position sensor coupled to the header frame and configured to measure a height of the cutter bar above the ground, a crop height sensor coupled to the header frame and arranged in front of the cutter bar and configured to measure a height of a crop canopy relative to the ground, wherein the control system in communication with the crop height sensor and the ground position sensor, the method comprising:determining the cutter bar height with the ground position sensor;determining the height of the crop canopy relative to the ground with the crop height sensor; creating a header plane based on the cutter bar height and the height of the crop canopy; determining a difference between the header plane and a theoretical base plane and correcting the base plane based on the difference; andmoving the gauge wheel assembly to control the cut height based on the height of the crop canopy.Docket Xe: 159031-0093910. The method of claim 9, further including a step of calculating a rate of change of an angle of the base plane and moving the gauge wheel assembly to control the cut height based on the rate of change of the angle of the base plane.

11. The method of any of claims 9- 10, further including a step of creating a harvester plane based on predetermined geometric relationships between the harvesting header and a harvester and combining the harvester plane and the header plane to create the base plane.

12. The method of claim 11, wherein the predetermined geometric relationships include geometric relationships between a position of the crop height sensor, a position of the cutter bar, and a position of the gauge wheel assembly.

13. The method of any of claims 9-12, further including a step of calculating a desired cut height based on a desired intake fraction chosen by an operator.

14. The method of claim 13, wherein the desired intake fraction is a ratio of a harvestable portion of a crop removed from a crop height relative to a total crop height.

15. The method of any of claims 13-14, further including a step of calculating the desired cut height based on a desired stubble height chosen by an operator.

16. The method of any of claims 9-15, wherein the crop height sensor is configured to measure a distance to the ground and a distance to the crop canopy, and wherein the step of determining the height of the crop canopy includes subtracting the distance to the crop canopy from the distance to the ground.

17. The method of any of claims 9-16, wherein the crop height sensor is a radar sensor.

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