Sensor selection in a reel control system

Abstract

A control system is provided for a combine header, which controls a position of a reel relative to a header to control a height of the reel relative to a crop canopy and maintain a predefined reel engagement therewith. The reel control system can automatically adjust the reel height during changes to the canopy height by instantaneously processing the sensor data, which can be averaged over a period of time. The control system determines whether stubble is being detected by any individual sensor, and if so, the sensor data for that sensor may be ignored, preferably for a defined period of time. If the crop height is measured to be less than or equal to the cut height, the sensor is measuring stubble and the sensor data is ignored.

Description

SENSOR SELECTION IN A REEL CONTROL SYSTEMFIELD OF THE INVENTION

[0001] The invention relates to a control system for an agricultural implement, and preferably, to a combine having a header with a reel wherein reel height is controlled in reliance upon sensors.BACKGROUND OF THE INVENTION

[0002] Combines for harvesting a variety of crops from a field are generally known in the art. Combines include headers mounted in front of a respective feeder house. The headers include a cutter bar assembly to cut crop material from the field, and a draper belt assembly positioned behind the cutter bar assembly to transport crop material into the feeder house. Further, a reel may be provided above the header and the cutter bar to help sweep crop into the header for cutting.

[0003] A variety of hydraulic cylinders may be used to adjust combine components such as the height of the cutter bar assembly. For example, a gauge wheel or contour wheel cylinder may extend or retract gauge 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.

[0004] In known header designs such as a flex header, the header may comprise header segments that can articulate and follow ground contours, wherein an operator may use the gauge wheels or contour wheels as a means 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 gauge wheels.

[0005] Some header configurations monitor the ground and the height of the cutter bar assembly above the ground to thereby define the constant stubble height. In one example disclosed in US20220279719A1, a header height control is provided for a harvesting head, wherein this known system controls the header relative to the ground using sensors and hydraulic lift and flex cylinders to control the cut height.

[0006] Further, such headers used for harvesting grains and oilseeds typically include the aforementioned reel. The purpose of the reel is to positively engage crop to direct crop flow over thecutter bar of a harvest header towards the side drapers or auger in order to be conveyed laterally towards the center feed area where the combine harvester receives crop material for further processing.

[0007] Typically, the reel height needs to be adjusted when the height of the crop being harvested changes, requiring frequent operator input. If the reel height is not adjusted properly it can result in poor crop flow, which can plug harvesters and delay or halt the harvest process. Adverse crop conditions such as downed (lodged) crop can influence the strategy required for adjusting the reel position.

[0008] As such, operation of a harvest header may require frequent adjustment of the height of the reel in order to ensure smooth and consistent crop flow during harvesting. Automated control of the reel height is a desirable feature in order to improve machine performance, and reduce operator fatigue. One way of controlling the reel automatically is to sense the crop height in front of the reel and adjust the height such that the reel engages the crop by a defined amount. The header may include multiple sensors located in front of and across the width of the reel, which can be used to better measure the crop canopy profile. However, some of these sensors may be located over previously cut crop and mistake the top of the stubble as the crop canopy. This error can negatively affect a reel height control system.

[0009] It is believed that known harvesters do not have the ability to determine previously cut stubble. As such, previously cut stubble would artificially bias any crop height averaging calculations towards lower values which will result in reel engagement values that are too high resulting in higher crop losses, poor crop flow, and longer harvest times.

[0010] It is an object of the invention to provide a header having an improved reel and methods for controlling the reel height to compensate for the presence of stubble during a harvesting operation.SUMMARY OF THE INVENTION

[0011] The improved header and header control system comprises a reel control system that allows for automatic adjustment of the height of the reel, which is configured to address the presence of stubble present in a field being harvested. In a typical header design, adjustment of the reel is the most frequently adjusted system of the header. Such adjustment typically can be made by the operator manually using system controls, but this can require frequent operator adjustments. Generally, the improved control system automates adjustment of the reel height,which reduces the need for operators to interact with the reel control system and therefore improves the usability of the reel during field operations.

[0012] In one aspect, the inventive control system includes at least one and preferably a series of sensors that are configured to sense the distance to the crop canopy to calculate the crop height, as well as sense the distance to the ground. Each single sensor preferably is a dualdetection sensor configured for detecting both crop canopy and ground distance such that no geometric model calculations are required to determine crop height as the crop height is a direct measurement.

[0013] An array of sensors may be located across the width of the header in front of the reel such that they can sense canopy distance and ground distance ahead of the reel as the combine moves through the field. Generally, the operator defines a target reel engagement with the crop (i.e., distance the reel protrudes below the top of the crop canopy) and the reel control system works to automatically maintain the reel height such that the reel engagement is equal to the operator defined setpoint. This provides for automatic control of the reel height, which reduces the need for operator input resulting in more optimal crop feeding performance and less down time.

[0014] These sensors attached to the header also permit determination of the crop height and the distance to the ground from the cutter bar assembly. In addition to controlling the reel height, the header control system may also be operated to vary the position of the gauge wheels and cutter bar assembly supported thereby to control the position of the cut height off of the ground, which may be based upon inputs from the operator. With the use of appropriate sensors, the header control system can operate to automatically adjust the gauge wheel position relative to the crop canopy as well as the ground wherein the reel control system can automatically adjust the reel height during these changes to the cut height.

[0015] The inventive control system is further configured to determine whether stubble is being detected by any individual sensor, and if so, the sensor data for that sensor may be ignored, preferably for a defined period of time. In order to determine whether a sensor is reading stubble that was previously cut, the approximate cut height is calculated based on header position sensors that sense various header parameters, such as reel height relative to the header frame, header pitch and harvester pitch relative to a gravity reference plane, and crop sensors measuring distance to the crop canopy and the ground. If the crop height is measured to be less than or equal to the calculated cut height plus a deadband value, then the algorithm assumes that the sensor is measuring stubble and excludes the sensor reading from any sensor averaging function being performed to calculate an operating parameter such as average canopy height. By ignoringthe presence of stubble, the reel height can be better controlled relative to the actual crop canopy, and the reel height would not be skewed by the presence of stubble intermixed with or adjacent to harvestable crop.

[0016] Other objects and purposes of the invention, and variations thereof, will be apparent upon reading the following specification and inspecting the accompanying drawings.BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure l is a front perspective view of an agricultural implement configured as a harvester combine having a header and reel.

[0018] Figure 2 is an enlarged perspective view of the header and reel thereof.

[0019] Figure 3 is a partial plan view of the combine with the header and reel.

[0020] Figure 4 is a diagrammatic side view of the inventive header and reel illustrating the reel at a first height, which is elevated for a higher crop canopy.

[0021] Figure 5 is a diagrammatic side view of the inventive header and reel illustrating the reel at a second height, which is dropped for a lower crop canopy.

[0022] Figure 6A is a diagrammatic front view of the header and reel of the combine illustrating a variable crop height adjacent to or intermixed with cut stubble in a first scenario.

[0023] Figure 6B is a diagrammatic front view of the header and reel of the combine illustrating a variable crop height adjacent to or intermixed with cut stubble in a second scenario.

[0024] Figure 7 is a diagrammatic side view of the header and reel illustrating operational variables relative to the header and reel geometry.

[0025] Figure 8 is a side view of the header and reel on the combine in relation to a crop canopy and multiple geometric variables for the header and reel.

[0026] Figure 9 is an enlarged partial side view of the header attachment as shown in Figure 8 and the geometric variables in this region.

[0027] Figure 10 is an enlarged partial side view of the reel supported on the header as shown in Figure 8 and the geometric variables in this region.

[0028] Figure 11 is an enlarged partial side view of the reel and a sensor configuration as shown in Figure 8 and the geometric variables in this region.

[0029] Figure 12 is a flowchart showing the operational process for calculating an average cut height for use in operating the inventive header and reel to provide reel height control.

[0030] Figure 13 is a flowchart showing the operational process for filtering the sensors.

[0031] Figure 14 is a flowchart showing the operational process for sensor pitch correction.

[0032] Figure 15 is a flowchart showing the operational process for operating the inventive header and reel to provide automatic reel height control based upon filtered sensor data.

[0033] Certain terminology will be used in the following description for convenience and reference only, and will not be limiting. For example, the words "upwardly", "downwardly", "rightwardly" and "leftwardly" will refer to directions in the drawings to which reference is made. The words "inwardly" and "outwardly" will refer to directions toward and away from, respectively, the geometric center of the arrangement and designated parts thereof. Said terminology will include the words specifically mentioned, derivatives thereof, and words of similar import.DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0034] Figure 1 illustrates a combine harvester i.e., combine 10 according to embodiments of the present invention. The combine 10 includes a header 12 mounted on a feeder house 14. The header 12 includes a header frame 13 and a cutter bar assembly 16 operatively extending across a front portion of the header 12 to cut crop material from the field. A draper assembly typically is positioned behind the cutter bar assembly 16 to transport the crop material into the feeder house 14.

[0035] In the preferred configuration such as the embodiment of Figures 1-4, the header 12 is supported close to the ground 17 (see Figure 4) such that the height of the cutter bar assembly 16 can be varied to cut crop close to the ground 17 and to increase the cut height according to ground and crop conditions. The header 12 is attached to the feeder house 14 by an adapter 18, which attaches the header 12 to the feeder house 14. The adapter 18 is provided to control the feeding of material into the feeder house 14 and to provide a lifting force to the header 12 to carry it forwardly on the front of the feeder house 14. The adapter 18 includes a float suspension 20 using springs or a cylinder system allowing the header 12 to float upwardly and downwardly relative to the feeder house 14.

[0036] The header 12 may be of a conventional construction well known to a person skilled in this art and the major components include the cutter bar assembly 16 having a cutter bar 19 for cutting standing crop and a crop transport device defined by the draper assembly for transporting the standing crop inwardly from ends of the header 12 to a collection location for feeding to the combine harvester 10 through the feeder house 14. The connection between the adapter 18 and the header 12 may include the float or suspension system 20 for carrying the header 12 on theadapter 18. As is well known, the suspension arrangement allows pivotal movement of the header 12 relative to the adapter 18 as well as vertical floating movement of the header 12.

[0037] Referring to Figure 4, the header 12 can run in contact with the ground 17 so that part of the weight is carried on the float system 20 and part applies a ground force. In the preferred configuration, a gauge wheel or contour wheel 23 shown in Figure 4 is pivotably connected to the header 12 for ground following contact. A typical header 12 would have a plurality of such gauge wheels 23. The gauge wheel 23 includes a wheel 24 rotatably connected to a pivot arm 25. The pivot arm 25 is pivotably connected to the header 12 and a hydraulic gauge wheel cylinder may be used to extend and retract the gauge wheel 23. In the extended position, the gauge wheel 23 follows the ground 17 and supports the header 12 when cutting at a set cut height CT above ground 17. Extension or retraction of the gauge wheel 23 can be performed to raise and lower the cut height CT shown in Figure 4. The leading edge of the cutter bar assembly 16 includes the cutter bar 19 to perform cutting of the crop, wherein the cut portion of the crop moves through the header 12 to the feeder house 14, while the remaining crop portion from the cut height CT to ground 17 defines stubble that remains in the field after harvesting. The header 12 may also be adjustable to adjust the pitch thereof.

[0038] Further, the header 12 may be used for harvesting grains and oilseeds and other crops and the inventive header 12 further includes a reel assembly 27 having one or more crop pick-up reels 28. The purpose of a reel 28 is to positively engage crop to direct crop flow over the cutter bar 19 of the header 12, wherein the cut crop flows towards the side drapers or auger in order to be conveyed laterally towards the center feed area where the combine harvester 10 receives crop material for further feeding to the feeder house 14.

[0039] Referring further to Figures 2-3, one or more of the crop pick-up reels 28 are positioned generally above the front portion of the header 12 for engaging the crops to be harvested. The cutter bar assembly 16 operatively extends across the front portion of the header frame 12 between the ends thereof for cutting the crops as referenced above. During harvesting, the crop pickup reels 28 are typically positioned close to the cutter bar assembly 16 without contacting the cutter bar assembly 16 to facilitate optimal harvesting efficiency of the header 12.

[0040] In some embodiments, the cutter bar assembly 16 is correspondingly flexible with center and side wing sections of the header 12 for contouring to the field. One such configuration of the cutter bar assembly 16 and header 12 is described in U.S. Patent No. 10,462,968, the disclosure of which is hereby incorporated by reference in its entirety.

[0041] Referring again to Figures 1-3, the header 12 includes a plurality of reel arms 29 disposed adjacent to each end of the crop pick-up reels 28 for supporting these crop pick-up reels 28 on the header frame 13. Each crop pick-up reel 28 is rotatably supported by respective reel support arms 29. The reel support arms 29 are pivotable on the header frame 13 upwardly and downwardly via a hydraulic system to vertically position the crop pick-up reels 28 relative to the cutter bar assembly 16 for optimally engaging the crops, as is known in the art. It is to be appreciated that the header 12 may ultimately include any number or arrangement of reel support arms 29 and crop pickup reels 28 to correspond to the number of sections on the header 12 without varying the scope of the invention. While the following discussion will focus on one such reel 28, it will be understood the description is applicable to each reel 28.

[0042] In more detail, the reel 28 is mounted over the cutter bar 19 on reel arms 29 by which the height of the reel 28 can be changed to change the spacing between reel bats of the reel 28 and the cutter bar 19. The reel 28 can also include a slide connection 30 (Figure 4) so that it can slide forwardly and rearwardly on the reel arms 29 so as to change the fore and aft position of the reel 28 relative to the cutter bar 19. These movements are actuated by control cylinders or by other means which allow them to be adjusted by a reel control system of the present invention.

[0043] As mentioned, the reel assembly 27 may comprise a plurality of reels 28 arranged side by side and carried on respective reel arms 29 that may be configured to allow independent adjustment of the plurality of reels 28. The independent adjustment can be in relation to one or more of height and forward and aft position including other known adjustment options as required. This independent adjustment can thus be used when the crop is in different conditions of height and / or lodgment across the width of the header 12.

[0044] For example, as shown in Figure 4, the combine 10 is shown relative to a standing crop extending along the expanse of ground 17 in front of combine 10. The top of the crop generally defines a crop canopy CC that is engaged by each reel 28. While the crop canopy CC may have a consistent height, more realistically, the crop canopy CC varies in height so that it has a crop height CH that is higher in some sections CHI and lower in other sections CH2. When the reel 28 engages the crop canopy CC with the higher crop height CHI, the reel 28 is in the elevated position shown in Figure 4. As noted, the elevation of the reel 28 can be raised or lowered, wherein the reel 28 is lowered to the elevation of Figure 5 when engaging the lower crop height CH2.

[0045] In Figures 4 and 5, the reel 28 engages the upper portion of the crop canopy CC and the extent of depth in the crop canopy CC is referenced as the reel engagement RE in these figures.As can be seen, the reel engagement RE is the vertical amount that a lower portion of the reel 28 engages or sweeps through the upper portion of the crop canopy CC. The reel height RH is shown in reference to an angle between the reel arm 29 and the header 12, which thereby defines the upward distance between the reel 28 and the ground 17. To adjust the reel height RH, the reel arm 29 is swingable upwardly and downwardly about a pivoted end through a pivot connection 31 between the reel arm 29 and the header frame 13 or other structure of the header 12. Where the reel height RH is defined in terms of the angular relation between the reel arm 29 and header frame 13, Figure 4 shows the reel 28 at a 70% reel height RH while Figure 5 shows the reel 28 at a 15% reel height RH with the reel height RH being adjustable through a reel height range of 0% and 100%. The total range of the reel height RH may vary depending upon the configuration of the header 12 and reel assembly 27.

[0046] Further as to Figures 1-4, the improved header 12 operates by a header control system that in many respects is known and does not require a detailed discussion herein. The invention relates to an improved header control system comprising a reel control system that allows for automatic adjustment of the height of the reel assembly 27 and the reels 28 thereof while compensating for the presence of stubble passing beneath the header 12 during harvesting. Generally, the improved reel control system automates adjustment of the reel height RH, which reduces the need for operators to interact with the reel control system, and therefore improves the usability of the reel assembly 27 during field operations. At the same time, the control system is able to detect and ignore stubble so as to prevent the stubble from skewing control algorithms and processes.

[0047] As seen in Figures 1-4, the reel control system of the present invention includes at least one and preferably a series or an array of sensors 35 that are configured to sense a canopy distance CD to the crop canopy CC to calculate the crop height CH, as well as sense the ground distance GD to the ground. The sensors 35 are mounted on sensor supports or arms 36, which may be extensions of the reel arms 29. As such, the sensors 35 may be located across the width of the header 12 in front of the reel 28 such that they can sense canopy distance CD and ground distance GD ahead of the reel 28 as the combine 10 moves through the field.

[0048] At least one and preferably the array of sensors 35 are provided and each individual sensor 35 is configured to sense the distance to the crop canopy CC to calculate the crop height CH, as well as sense the distance to the ground. Each single sensor 35 preferably is a dualdetection sensor 35 configured for directly detecting both crop canopy CC and distance toground GD such that no geometric model calculations are required to determine crop height CH away from the sensor 35 as it is a direct measurement.

[0049] In one aspect of the invention, the operator may define a target reel engagement with the crop (i.e., distance the reel 28 protrudes below the top of the crop canopy CC) and the inventive reel control system processes the sensor data and operates to maintain the reel height RH such that the reel engagement RE is equal to the operator defined setpoint. Figure 15 illustrates one embodiment of the reel height control system of the present invention. This provides for automatic control of the reel height RH, which reduces if not eliminates the need for operator input during combine operation and results in more optimal crop feeding performance and less down time.

[0050] The sensors 35 attached to the header 12 also permit determination of the crop height CH and the distance to the ground 17 from the cutter bar assembly 16. In addition to controlling the reel height RH, the header control system may also be operated in conjunction with the reel control system to vary the position of the gauge wheels 20 and cutter bar assembly 16 supported thereby to control the position of the cut height CT off of the ground (Figure 7 discussed below), which may be based upon inputs from the operator. With the use of appropriate types of sensors 35, the header control system and its reel control system can operate to automatically adjust the gauge wheel position relative to the crop canopy CC as well as the ground 17. The reel control system can automatically adjust the reel height RH during and in response to these changes to the cut height CT, and the reel height RH and cut height CT can be adjusted independent of each other. For example, in some conditions, the cut height CT may be raised as desired, and the reel height RH can be lowered to maintain or increase the reel engagement RE as the cut height CT is raised.

[0051] The sensors 35 may comprise radar sensors that continuously or intermittently sense and monitor the crop canopy CC and crop distance CD and the ground location and ground distance GD, which are typically sensed and monitored simultaneously so that the header and reel control systems can determine the crop height CH. The sensors 35 also may be LiDAR or ultrasonic sensors or other appropriate sensors or sensing means such as a vision system, which can sense or detect the ground elevation and crop height CH even when crops are fully developed. As described herein, the one or more sensors 35 would reference or detect the crop canopy CC and the ground 17 and determine the canopy distance CD and the ground distance GD from the sensors 35 to the ground 17, wherein these sensors 35 preferably have a single sensor module but also may have multiple sensing modules that define a single sensor 35.

[0052] In Figure 3, the header 12 is shown with three reels 28 supported by four reel arms 29. As noted, each reel arm 29 includes a sensor 35 on the sensor support 36 extending forwardly therefrom. In the illustrated configuration, four sensors 35 are provided although the number of sensors 35 can be increased or decreased depending upon the configuration of the header 12 and reel assembly. For example, in some headers 12, there may be two reels 28 and three reel arms 29 with three sensors 35.

[0053] As mentioned, the sensors 35 detect two values, namely the canopy distance CD and ground distance GD. Referring to Figures 4 and 5, the sensor 35 generally projects a sensor beam or signal in a sensor cone SC of about 6 degrees of angular width along a cone axis CA. The cone axis CA preferably projects or cants forwardly and downwardly at an angle and the sensor cone SC generates return signals from the crop canopy CC and ground 17 that are used to determine the crop distance CD and ground distance GD. The crop canopy CC may generate return signals through a first cone width defined by the area of the sensor cone SC at the crop canopy CC while the ground 17 may generate return signals through a second cone width defined by the area of the sensor cone SC at the ground 17, wherein the second cone width would be wider than the first cone width. The angle of projection of the sensor cone SC based upon the cone axis CA may be at a first angle relative to a vertical reference line (Figure 4) and at a second angle when the reel 28 is lowered (Figure 5). As described below, the changes in the angle or projection might be compensated for through an algorithm performed by the sensor pitch correction process of Figure 14 or might be compensated for mechanically by adjustment of the angle of the sensors 35 as the reel position is adjusted.

[0054] Preferably, the sensors 35 are spread across the width of the header 12 as seen in Figures 6 A and 6B with at least one sensor 35 on each opposite header end 38 and one or more sensors 35 located intermediately between the header ends 38. As such, the sensors 35 can generate sensor data indicating crop distance CD and ground distance GD at laterally spaced locations along the lateral width of the header 12. Preferably, the sensors 35 provide respective streams of sensor data that can indicate crop conditions at selected, spaced-apart locations along the lateral width of the header 12. Typically, it is not necessary to detect the crop conditions along the entire width of the header 12 although this might be implemented if desired through the use of additional sensors or use of different types of sensors having a wider sensor cone or sensing zone that spans a greater lateral width in front of the header 12.

[0055] In more detail as to Figure 6A, Figure 6A illustrates a first example of a crop scenario or situation wherein the crop canopy CC is diagrammatically shown as having varying heights. Inone respect, the crop canopy CC may primarily have a fully grown crop height CHI in the majority of the field wherein the crop height CHI is relatively consistent and spans most of the field being harvested. However, in portions of the field, the crop may become lodged or at least partially lodged so that the height of the crop canopy CC is reduced or downed. For example, there may be a first section of a partially lodged crop canopy CC having a crop height CH2 and a second section of lodged crop having a different crop height CH3. The field crop may be intermixed or adjacent to sections or areas of crop that have been previously cut and harvested, wherein these sections would be left with cut stubble CS having a stubble height SH.

[0056] Generally, as to the present invention, the sensors 35 may detect any of these different areas with different heights. As will be described further herein, the areas of cut stubble CS with stubble height SH typically are lower than the remainder of field with a crop canopy CC, wherein detection of the stubble height SH by any of the sensors 35 may skew the engagement of the reels 28 with the crop canopy CC. As such, the present invention preferably ignores data streams detecting cut stubble CS by ignoring stubble-detecting sensors designated as ignored sensors 351. In other areas where crop canopy is present and detected, the present invention treats these as active sensors designated as sensors 35 A. As such, the sections of full and downed crop canopy having crop heights CHI, CH2 and CH3 may be detected by any of the sensors which remain active and designated herein as sensors 35 A. In Figure 6 A, the endmost sensor 351 may detect the stubble height SH and consequently be ignored by the operating system as described below.

[0057] In a second exemplary situation shown in Figure 6B, the expanse or extent of the crop stubble CS is greater and detected by the two endmost sensors 351 at one header end, such that the operating system ignores these sensors 351 for a defined period of time. The other two sensors 35 A remain active since the operating system determines that full crop height CHI or substantially full crop height CHI-1 are present below the header 12. Therefore, the sensors 35A can be treated as active by the operating system when both full crop heights CHI are detected as well as lodged crop heights CH2 and CH3. So long as the lodged crop height such as CH3 is greater than the cut height CT indicted by stubble height SH, the sensors 35 A remain active. If the operating system determines that a sensor 35 is detecting crop material at a height equal to or less than the stubble height SH, or in other words, the cut height CT at that location, the operating system will then ignore each such sensor 351.

[0058] The reel engagement RE can then be controlled based upon the crop height CH of actual crop that is present. Simultaneously, the sensor data from ignored sensors 351 is not used in the control algorithm, which prevents cut stubble CT from skewing the reel engagement RE.

[0059] The operating system may in turn determine an average crop height CH from the active sensors 35 A, which can then be used by the reel control system to automatically adjust the height of the reels 28 based upon the average crop height CH being detected in order to maintain a target reel engagement RE input by the operator. The reel control system then works to maintain the reel height RH such that the reel engagement RE is equal to the operator defined setpoint. This provides for automatic control of the reel height RH, which reduces the need for operator input resulting in more optimal crop feeding performance and less down time.

[0060] To operate the header 12 to automatically adjust the reel height RH, the header 12 may include adjustment mechanisms that may vary and adjust the geometry of the mechanisms on the header 12. Figure 7 illustrates the general configuration of the combine 10 with the header 12 supported on the gauge wheel 23. The header 12 includes the reel arm 29 pivotally connected to the header 12 at pivot connection 31, wherein the reel 28 is rotatably mounted on the reel arm 29 and is slidable fore and aft by slide connection 30. As noted above, the sensor support 36 extends forwardly and upwardly from the reel arm 29 and has one or more sensors 35 mounted thereon. The sensors 35 detect the crop canopy CC and ground 17 through an emitted sensor beam having the beam axis CA. As these various components move during combine operation and reel adjustment, the geometric positions change and the header control system may monitor the geometric variables to compensate for operational movement and accurately use the sensor data indicating the crop distance CD and ground distance GD to thereby determine and monitor the crop height CH.

[0061] In this regard, Figure 7 diagrammatically shows some of the different variables for the operating geometry. As generally shown in Figure 7, the header 12 may use the sensors 35 on the sensor support arm 29 to detect the crop canopy CC and ground 17 to determine and monitor the vertical crop height CH. The sensor support arms 29 are configured to extend forwardly of the reel 28 to detect the crop canopy CC and ground 17 ahead of the combine 10 as it travels over a field. The reel support arm 29 is typically adjustable such that the combine control system may monitor the reel arm pitch RAP relative to a horizontally extending reference plane such as reference line RL, which generally extends parallel to the ground plane even in the presence of ground contours. The sensor support arm 29 may be maintained parallel to the ground 17 so that the perpendicular ground distance GDP can be monitored as well as the perpendicular cropdistance CDP. However, the sensor support arm 30 might not be parallel wherein this can optionally be corrected for in an algorithm implemented in the control system.

[0062] Since the cutter bar assembly 16 and header 12 can be raised and lowered by the gauge wheels 23, the cutter bar 19 can be raised and lowered accordingly. As mentioned, the cutter bar assembly 16 and header 12 may be formed as a single unit or from multiple articulating sections. The control system may monitor the header pitch HP relative to a gravity reference plane GRP as well as the perpendicular cutter bar distance CBDP below the sensor 35. The operating system may also monitor the pitch of the combine / harvester or cab thereof. Monitoring of these variables allows calculation of the stubble height SH. Further, the control system may monitor the reel arm pitch RAP and use the angle to calculate a reel arm pitch RAP-Z that determines the ground distance at this angle, which angles rearwardly of the perpendicular ground distance GDP.

[0063] As shown in more detail in Figures 8 and 9, the combine 10 typically has a combine pitch CP relative to ground 17 that may be monitored. The operating system may monitor this pitch CP of the combine / harvester or the cab thereof. Since the header 12 can be raised and lowered by the gauge wheels 23, the cutter bar 19 can be raised and lowered accordingly. As mentioned, the cutter bar assembly 16 and header 12 may be formed as a single unit or from multiple articulating sections.

[0064] Referring further to Figures 8 and 10, the sensor supports 36 are configured to extend forwardly of the reel 28 and reel supports 29 to detect the crop canopy CC and ground 17 ahead of the combine 10 as it travels over a field. Since the reel support arm 29 is typically adjustable, the combine control system may monitor the reel arm pitch RAP.

[0065] Next as to Figures 8 and 11, the header 12 uses the sensors 35 on the sensor supports 36 to detect the crop canopy CC and ground 17 to determine and monitor the crop distance CD and ground distance GD, wherein the angle of the sensor cone axis CA of sensors 35 as well as the sensor supports 36 vary as the reel 28 is raised and lowered. The control system may use the reel arm pitch RAP relative to a horizontal canopy reference and a constant sensor angle SAC to determine the angle of the cone axis CA relative to a vertically extending reference line VRL. This reference line VRL preferably is perpendicular to the ground plane and may vary to a degree depending upon ground contours over which the combine 10 travels. Using the above variables and any others as needed, the control system can monitor the perpendicular ground distance GDP as well as the perpendicular crop distance CDP.

[0066] Monitoring of these variables allows calculation of the cut height CT and stubble height SH. The header control system and its reel control system can therefore process the data for the variables as well as the sensor data from the sensors 35 to automatically vary the reel height of the reels 28 during field operations. As mentioned, this control of the reel height RH can be based upon the active sensors 35 A while ignoring sensors 351.

[0067] Generally, Figure 12 illustrates a control routine performed by the system CPU in reliance upon the manual inputs and the sensor-based inputs to determine an average cut height CT or stubble height SH for use in controlling the sensors 35 and determine whether such sensors will be ignored sensors 351 or active sensors 35 A, which are then used to control the height of the reels 28 and the reel engagement RE. When determining an average canopy height CHavg, only the sensor data from the active sensors 35 A would be used while the ignored sensors 351 are ignored.

[0068] The operating system may comprise a computing device on the combine 10 or remote therefrom, which includes the CPU and other computer-based devices operating a control program and configured to receive inputs, process data, and generate outputs. A detailed discussion of the computing environment is not required for an understanding of the present invention. For purposes of discussion, Figure 12 may be referenced as a routine but also may be characterized as a process of the operating program to process data, receive inputs and generate outputs for use by other routines or processes that automatically raise and lower the reels 28 or for use by the operators of the operating system.

[0069] In more detail as to Figure 12, this figure illustrates a cut height averaging routine or process of the control system and an operating method of the control system for determining the average cut height CTavg indicative of the average stubble height SH. As mentioned, the routine is performed by the combine operating or control system which comprises a computing device with a central processing unit (CPU) configured to communicate inputs and outputs for data and commands, data storage, and a display device for use by an operator.

[0070] Referring to Figure 12, the routine starts at step 40 and monitors header position sensors at step 41 to determine and monitor the header pitch HP, a harvester or combine pitch, and a reel height position, which may be calculated based upon the gravity reference plane GRP (Figure 6) or other reference points. In some cases, the reel height position might be sensed based upon the reel arm pitch RAP. At step 42, crop sensor data generated by the sensors 35 is monitored to determine the ground range from which the perpendicular ground distance GDP and the ground distance average are calculated. The perpendicular ground distance GDP may also be referencedas a corrected ground distance GD since the cone axis CA of the sensor 35 may be canted at an angle relative to a vertical axis perpendicular to the ground plane. This correction may be made using the reel arm pitch RAP or other known positional variables of the header.

[0071] With respect to the ground distance GD, the sensors 35 may detect both the crop canopy CC and the ground 17. In use, the ground may be uneven and vary to a degree such that the average ground distance GD preferably is used. In step 44, the distance A (Figure 7) is calculated, which is the distance between the vertical elevation of each sensor 35 and a horizontally extending reference line RL (Figure 7), which may extend through a reel support arm pivot 31 or other reference point and be parallel to the ground plane. The orientation of the reference line RL may vary to a degree as the ground contour varies but essentially stays fixed relative to the combine 10 and the combine hardware.

[0072] In step 45, the distance B is calculated (Figure 7), which is the distance between the reference line RL and the stubble height SH defined by the engagement of the cutter bar 19 with the crop. In step 46, the output is calculated as the average cut height CT which indicates the stubble height SH generated by the cutter bar 19, and the cut height calculation process can end in step 47. Notably, this cut height averaging process may consider the sensor data from all of the sensors 35 to provide a broader picture of the average cut height CT being generated by the cutter bar 19 across the lateral width of the header 12 as the header 12 moves over the field.

[0073] Next, Figure 13 is a flowchart showing the operational process for filtering the sensors to determine if crop is present, and further, to determine whether sensed canopy distance is so low as to indicate that stubble is present and being sensed instead of standing crop. As referenced above relative to the description of the ignored sensor(s) 351 and active sensor(s) 35 A, the sensor data from all of the sensors 35 may be filtered to compensate for the absence of growing crop and the presence of stubble. When a stubble condition is identified by a particular sensor 35, the inventive operating system preferably ignores the sensor data, for example, when averaging the crop height in other system processes such as the reel height control process of Figure 15 described below. As will be described further, the sensor data from sensors 351 can be ignored or omitted from crop height averaging calculations or other sensor-based calculations based upon a preset parameter, such as a set period of time. At the end of this set period, the sensor data from each ignored sensor 351 and active sensor 35 A may be checked again relative to canopy height by the sensor filtering process of Figure 13, and either be included in any crop height averaging algorithm or other sensor-based calculations or else be ignored until the next successive time period.

[0074] Referring in more detail, Figure 13 illustrates the flowchart for this sensor filtering process for filtering the data streams from each of the sensors 35. Similar to the above description, this process or routine is performed by the system CPU in reliance upon the data streams input from all of the sensors 35, wherein these sensors 35 preferably detect the canopy distance CD and the ground distance GD along the sensor cone axis CA. The operating system may comprise a computing device located on the combine 10 or remote therefrom, which includes the CPU and other computer-based devices operating a control program and configured to receive inputs, process data, and generate outputs. Here again, a detailed discussion of the computing environment is not required for an understanding of the present invention. The sensor filtering process of Figure 13 may be performed as a part of any operating process of the control system that relies upon detection of the crop height CH to control other header mechanisms and variables such as the reel height and the reel engagement RE.

[0075] This sensor filtering process starts at step 60, and next in step 61, the header position sensors detect the position of various header components, wherein header position sensors may provide data inputs for the reel height position, the header pitch HP and a cab pitch for the combine 10 itself, which may be represented by the combine pitch CP or calculated therefrom.

[0076] In step 62, the operating system determines the canopy distance CD and ground distance GD referenced as the canopy range and ground range. In step 63, a sensor pitch correction may be performed as described below relative to Figure 14. In step 64, a cut height average is calculated based upon sensor data indicating the position of the cutter bar assembly 16 relative to the ground. This calculation step 64 may be performed by the process of Figure 12 described above wherein the average cut height CT may be averaged across the length of the header 12 by processing the sensor data from all of the sensors 35.

[0077] In step 65, the crop height is determined for a particular sensor 35, wherein this sensor filtering routine would be performed for each of the sensors 35 separately from the other sensors 35. As such, the crop height CH (See Figure 11) is determined at each one of the sensors 35 for further processing relative to the cut height average of step 64.

[0078] In step 66, the actual crop height CH at a particular sensor 35 is compared with the cut height average CTavg indicated by a stubble height average SHavg to determine whether the actual crop height CH is less than the cut height average CTavg less the deadband value therefor. The deadband is the permissible variance between a set value and an actual value. If NO, the actual crop height CH is not less than the cut height average CTavg less deadband, then the actual crop height CH is higher than cut height CT and the routine moves to step 67 to determinethat the sensor data is valid and the routine treats that particular sensor 35 as an active sensor 35 A. As such, the data from this particular sensor 35 A is considered in other control routines such as those controlling the reel height (Figure 15). The routine then ends at 69 for that active sensor 35 A.

[0079] If YES, the actual crop height CH is less than the cut height average less deadband, then the actual crop height CH is lower than the cut height CT and the routine moves to step 68 to determine that the sensor data is not valid and the routine treats that particular sensor 35 as an ignored sensor 351 such the data from this particular sensor 351 is omitted in other control routines such as those controlling the reel height (Figure 15). The routine then ends at 69 for that ignored sensor 351.

[0080] The sensor data for active sensors 35 A may be used in other operating processes such as when calculating a crop height average (canopy range average) or an actual reel engagement RE. Conversely, the sensor data for any ignored sensor 351 may not be used in other operating processes, such as to calculate the canopy range average and the reel engagement actual, for a period or interval of time. Once the sensor filtering process of Figure 13 is again performed, the sensors 35 are again reevaluated to determine if they will be treated as active or ignored sensors 35A or 35I.

[0081] In view of the foregoing, the presence of crop stubble CS is not able to skew operating processes that relay upon the crop height data, such as reel engagement calculations. Rather, each sensor 35 is evaluated to ensure it is not detecting stubble CS and if any one or more sensor(s) 35 are passing over stubble CS, the sensor data for each said sensor 351 is ignored by other operating processes, such as the reel height control process of Figure 15. Conversely, each sensor 351 is ignored through each iteration of the process when the crop height CH is less than the stubble height SH, but may become an active sensor 35 A once it indicates that crop canopy CC is being detected thereby rather than stubble CS.

[0082] A sensor filtering process may be performed simultaneously for each sensor 35 to thereby process and evaluate the data stream for each sensor 35, with only the sensor data streams for the active sensors 35 A being input or fed to other operating system processes. Notably, the sensor readings or data are generated continuously by the sensors 35 in the preferred configuration. To reduce the processing time or processor loads for handling this sensor data, testing by the sensor filtering process of Figure 13 may be performed intermittently, for example, at the end of predefined time periods or intervals. In the preferred embodiment, the testing interval may be a four second window so that the sensors 35 are determined to be active or ignored every fourseconds in this example. In effect, header adjustments would occur at the end of each time interval or every four seconds, which is still more frequently than if an operator were manually entering header adjustments into the processing system based upon observed field conditions. The processing system may further include an optional input through which the operator sets the testing interval in the combine display screen to make the interval longer or shorter.

[0083] Since the combine 10 is moving during the harvesting operation, the length of the time period would reflect a distance travelled by the combine 10 during that time interval. The distance travelled would vary depending upon the speed of the combine 10, which typically can travel 1-6 mph, which would then translate into a travelled distance of several feet. In some configurations, the processing system may determine the time interval by defining or setting the number of feet that the combine 10 travels before the next iteration of sensor data testing. In this regard, the time interval can be adjusted based upon the combine speed.

[0084] At the ended of each time interval, the sensor filtering process of Figure 13 would deem each sensor to be either an active sensor 35 A or an inactive sensor 351 and the sensors 35 A and 351 would remain as active or ignored for the duration of the time interval. At the end of such time interval, the next iteration of sensor data testing could be performed by the sensor filtering process of Figure 13 to reassign the sensors 35 as either being active sensors 35 A or ignored or inactive sensors 351.

[0085] Next, Figure 14 is a flowchart showing the operational process for sensor pitch correction of step 63 in the sensor filtering routine of Figure 13. Generally, the support arm 29 for the reels 28 is raised and lowered during conventional operation to maintain a desired reel engagement RE with the crop. In some configurations, the operator may adjust the reel engagement RE through manual commands input into the control system, and in other configurations, the control system may automatically raise and lower the reel engagement RE in response to the sensor data and the actual reel engagement RE calculated from the sensor data. In either case, as the reels 28 are raised and lowered, the reel arm pitch RAP adjusts angularly, and the angular orientation of the cone axis CA varies relative to a line perpendicular to the ground plane. As seen in Figure 8, the cone axis CA preferably is canted forwardly to avoid the detection of header structures, which would interfere with the sensor signals and sensor data derived thereby. However, the forwardly angled aiming of the sensors 35 will sense the ground 17 at a distance large than the perpendicular ground distance GDP. Further, this detection distance varies as the reel arm pitch RAP varies. Hence, the sensor pitch correction process compensates and corrects for thisphenomenon by correcting the actual sensor data to determine the perpendicular ground distance GDP and perpendicular canopy distance CDP as described further below.

[0086] The sensor pitch correction routine of Figure 14 is performed by the combine operating or control system which comprises a computing device with a central processing unit (CPU) configured to communicate inputs and outputs for data and commands, data storage, and a display device for use by an operator. This CPU or another CPU may be configured to perform the processes of Figures 12-15.

[0087] Next, a sensor pitch correction routine is referenced at step 63 in the routine of Figure 13 described above, wherein Figure 14 provides further details as to this process. As illustrated in Figure 14, this sensor pitch correction process starts at step 70, and next in step 71, the header position sensors provide the data for the position of various header components, wherein header position sensors may provide data inputs for the reel height position, the header pitch HP and a cab pitch for the combine 10 itself.

[0088] In step 72, the operating system determines the canopy distance CD and ground distance GD referenced as the canopy range and ground range. In step 73, a calculation step is performed to determine the perpendicular ground distance and perpendicular canopy distance based upon the reel arm pitch RAP as these variables are shown in Figures 7 and 11.

[0089] In particular, the canopy distance CD is multiplied by the cosign COS of the reel arm pitch RAP minus the sensor angle constant SAC to determine the perpendicular canopy distance CDP. Similarly, the ground distance GD is multiplied by the cosign COS of the reel arm pitch minus the sensor angle constant SAC to determine the perpendicular ground distance GDP. Preferably, the sensors 35 are aimed forwardly of the header 12 and the vertical reference line VRL so that the sensors 35 do not detect header 12 structure when the sensor support 36 is lowered. As such, the crop distance CD and ground distance GD are detected at an angle relative to the vertical reference line VRL. However, this calculation step 73 converts the crop distance CD and ground distance GD detected by the sensors 35 to the perpendicular canopy distance CDP and perpendicular ground distance GDP, which extend vertically, perpendicular to the ground plane. These values for the perpendicular canopy distance CDP and perpendicular ground distance GDP are then used in steps 64 and 65 of Figure 13 to determine the cut height average CTavg and the crop height CH and also are used in step 45 of Figure 12 to determine the canopy range average and the ground range average to compensate for differences in canopy height and ground contours, which may cause the reel arm pitch RAP to vary.

[0090] This routine ends at step 74 and then returns to step 64 wherein step 64 and the subsequent steps of the sensor filtering routine (Figure 13) are performed. This allows the calculation steps 64 and 65 to use the perpendicular ground distance values and perpendicular canopy distance values for the calculations performed for these steps.

[0091] The sensor filtering routine of Figure 13 thereby modifies the sensor data available for use by other operating process. In one example, Figure 15 illustrates a control routine performed by the system CPU in reliance upon the manual inputs and the sensor-based inputs to automatically control the height of the reels 28 and the reel engagement RE. For purposes of discussion, Figure 15 may be referenced as a routine but also may be characterized as a process of the operating program to process data, receive inputs and generate outputs for use by other routines or processes to automatically raise and lower the reels 28 or for use by the operators of the operating system.

[0092] In more detail as to Figure 15, this figure illustrates a reel height control routine or process of a control system and an operating method of the control system for controlling reel height. As mentioned, the routine is performed by the combine operating or control system which comprises a computing device with a central processing unit (CPU) configured to communicate inputs and outputs for data and commands, data storage, and a display device for use by an operator.

[0093] As illustrated, the routine starts at step 80, and in step 81, selected control settings are input into the control system, such as by an operator, wherein the control settings or inputs include a target value for reel engagement RE, which the reel control system will tend to maintain reel engagement RE during field operations. Further in step 81, the operator may input a preferred aggressiveness value, which generally relates to the aggressiveness that the reel engagement RE biases toward higher or lower crop canopies detected by any of the sensors 35. The operator may also input a numerical value for deadband, which is the permissible variance between a set value and an actual value before the operating system reacts to adjust the operation of the header 12 and the reel height RH thereof.

[0094] Next in step 82, the header position sensors detect the position of various header components, wherein header position sensors may provide data inputs for the reel height position, a fore-aft position for the reel 28, the header pitch HP and a cab pitch for the combine 10 itself, which may be represented by the combine pitch CP or calculated therefrom.

[0095] In step 83, the operating system determines or inputs the canopy distance CD and ground distance GD referenced as the canopy range and ground range. In step 84, the sensor data fromthe sensors 35 is filtered through the processes of Figures 13 and 14 to compensate for the absence of standing crop and the presence of stubble. The reference to standing crop may include both growing and ripe, harvestable crop material.

[0096] In step 85, a canopy range average and ground range average is calculated to compensate for differences in canopy height CH and ground contours. These calculations may solely rely upon the active sensors 35A while the sensor data for the ignored sensors 351 can be ignored in this processing step such that the presence of cut stubble CS does not skew the calculation of the average canopy height CHavg. For the most part, the presence of stubble CS would not affect the determination of the ground range average although the ignored sensors 351 are not necessary for this calculation and may be ignored for these purposes. Further, the actual reel engagement RE vcan be calculated from the sensor data from the active sensors 35 A such that the presence of stubble CS does not skew the calculation of actual reel engagement RE. The remaining process steps can then be performed in reliance upon the sensor data from the active sensors 35 A.

[0097] Generally, in step 86, the automated reel height control process calculates a reel engagement error, which is the difference between the actual reel engagement calculated in step 85 minus the reel engagement target input in step 81. In step 87, the reel engagement error is compared relative to the deadband value wherein this comparison step determines whether the reel 28 should be lowered in step 89, and then the routine returns to step 82. In step 83, the reel engagement error is further evaluated to determine whether to either hold the reel 28 at the set height in step 90 and end the process in step 91 and then return to the start 80 for continued and continuous monitoring of the actual reel engagement RE, or else raise the reel in step 92 and then return to step 82 for further processing iterations.

[0098] During each iteration of the sensor filtering step of Figure 84, the sensor data can again be evaluated in the sensor filtering process of Figure 13 to designate the sensors as either active sensors 35 A or ignored sensors 351. As described above, the sensor data can be ignored or omitted from the crop height averaging calculation performed in step 85 based upon a preset parameter, such as a set period of time. At the end of this set period, the sensor data may be checked again relative to crop height CH and stubble height SH in step 66 of Figure 13, and either be included in the crop height averaging algorithm or be ignored until the next successive time period.

[0099] With this control system, the header control system can operate to automatically adjust the reel height RH relative to the crop canopy CC as well as the ground 17. The reel control system can automatically adjust the reel height RH and reel engagement RE during changes tothe crop height CH by instantaneously processing the sensor data, which can be averaged over a period of time. Adjustments are made at the end of each of these periods of time or intervals.

[0100] Although particular preferred embodiments of the invention have been disclosed in detail for illustrative purposes, it will be recognized that variations or modifications of the disclosed apparatus, including the rearrangement of parts, lie within the scope of the present invention.

Claims

CLAIMS1. A method for processing sensor data in a header control system of a combine header comprising a cutter bar assembly configured to cut field crops at a cut height and at least one reel configured to engage a crop canopy by an amount of reel engagement therewith, said header control system further comprising a plurality of sensors for sensing a ground location and sensing said crop canopy as said combine header transits the field, said header control system configured to perform the steps of: operating said sensors so that each of said sensors senses said ground location and said crop canopy and generates respective sensor data; determining a canopy distance of said crop canopy away from each said sensor and a ground distance away from each said sensor wherein said respective sensor data generated by each of said sensors includes said canopy distance and said ground distance for each said sensor; monitoring said canopy distance and said ground distance for determining a crop height of said crop canopy being detected by each said sensor; calculating said cut height from said sensor data for each of said sensors; comparing said crop height detected by each said sensor relative to said cut height determined from said sensor data wherein said comparing of said crop height is performed for each said sensor and, if said crop height for a particular one of said sensors is greater than said cut height, said particular one of said sensors being an active sensor with said sensor data thereof being usable by said header control system for a defined time period, or if said crop height for said particular one of said sensors is less than said cut height so as to indicate that crop stubble is being detected by said particular sensor, said particular one of said sensors being an ignored sensor with said sensor data thereof being ignored by said header control system for said defined time period.

2. The method according to Claim 1, wherein said method further comprises the step of repeating said comparing of said crop height to determine whether said crop stubble is no longer present such that any said ignored sensor may be treated as an active sensor and determine whether crop stubble is now present such that any said active sensor may be treated as an ignored sensor.

3. The method according to Claim 2, wherein said repeating step is performed at the end of each said defined time period.

4. The method according to Claim 1, wherein said comparing step determines that said canopy distance is so low as to indicate that said stubble is present and being detected instead of standing crop.

5. The method according to Claim 1, wherein said cut height is defined by an average cut height for all of said sensors.

6. The method according to Claim 5, wherein said sensors are spaced apart from each other across a width of said header in front of said reel to detect said canopy distance and said ground distance ahead of said reel as said combine moves through the field.

7. The method according to Claim 1, wherein said header control system is a reel height control system controlling said reel engagement of said reel with said crop canopy.

8. The method according to Claim 1, wherein the method further comprises the step of automatically adjusting said reel engagement in response to detected changes in said crop height of said crop canopy to provide automatic control of said reel engagement, said active sensors being used to detect said changes in said crop height and said ignored sensors being ignored when calculating said crop height.

9. A method for processing sensor data in a header control system of a combine header comprising a cutter bar assembly configured to cut field crops at a cut height, said header control system further comprising a plurality of sensors for sensing a ground location and sensing a crop canopy as said combine header transits the field, said header control system comprising an operating process operated in reliance upon a crop height of said crop canopy, and said header control system configured to perform the steps of: operating said sensors so that each of said sensors senses said ground location and said crop canopy and generates respective sensor data;determining a canopy distance of said crop canopy away from each said sensor and a ground distance away from each said sensor wherein said respective sensor data generated by each of said sensors includes said canopy distance and said ground distance for each said sensor; monitoring said canopy distance and said ground distance for determining a crop height being detected by each said sensor; calculating said cut height from said sensor data for each of said sensors; filtering said sensor data to identify crop stubble in the field and ignore any said sensor data from any said sensors detecting said crop stubble when performing said operating process, said filtering of said sensor data comprising the steps of: comparing said crop height detected by each said sensor relative to said cut height determined from said sensor data, wherein said comparing of said crop height is performed for each said sensor and, if said crop height for a particular one of said sensors is greater than said cut height, said particular one of said sensors being an active sensor, or if said crop height for said particular one of said sensors is less than said cut height so as to indicate that crop stubble is being detected by said particular sensor, said particular one of said sensors being an ignored sensor; and operating said operating process in reliance upon only said sensor data of each said active sensor while ignoring said sensor data of each said ignored sensor.

10. The method according to Claim 9, wherein said sensor data of said active sensors being usable by said operating process for a defined time period, with said sensor data of said ignored sensors being ignored by said operating process for said defined time period.

11. The method according to Claim 10, wherein said method further comprises the step of repeating said comparing of said crop height to determine whether said crop stubble is no longer present such that any said ignored sensor may be treated as an active sensor and determine whether crop stubble is now present such that any said active sensor may be treated as an ignored sensor.

12. The method according to Claim 11, wherein said repeating step is performed at the end of each said defined time period.

13. The method according to Claim 9, wherein said comparing step determines that said canopy distance is so low as to indicate that said stubble is present and being detected instead of standing crop.

14. The method according to Claim 9, wherein said cut height is defined by an average cut height for all of said sensors.

15. The method according to Claim 14, wherein said sensors are spaced apart from each other across a width of said header in front of said reel to detect said canopy distance and said ground distance ahead of said reel as said combine moves through the field.

16. The method according to Claim 1, wherein said combine header comprises a reel engaging said crop canopy by a defined reel engagements, and said operating process is a reel height control system controlling said reel engagement of said reel with said crop canopy.

17. The method according to Claim 16, wherein the method further comprises the step of automatically adjusting said reel engagement in response to detected changes in said crop height of said crop canopy to provide automatic control of said reel engagement, said active sensors being used to detect said changes in said crop height and said ignored sensors being ignored when calculating said crop height.

18. A combine header configured to cut field crops as said header transits a field, said combine header comprising: a header frame: a cutter bar assembly mounted on said header frame for cutting field crops at a cut height; a plurality of sensors mounted on said header for sensing a ground location and sensing a crop canopy as said combine header transits the field; a header control system comprising an operating process operated in reliance upon a crop height of said crop canopy, said header control system configured to perform the steps of: operating said sensors so that each of said sensors senses said ground location and said crop canopy and generates respective sensor data;determining a canopy distance of said crop canopy away from each said sensor and a ground distance away from each said sensor wherein said respective sensor data generated by each of said sensors includes said canopy distance and said ground distance for each said sensor; determining said crop height at each said sensor based upon said canopy distance; calculating said cut height based upon said ground distance; filtering said sensor data to identify crop stubble in the field and ignore any said sensor data from any said sensors detecting said crop stubble when performing said operating process; said filtering of said sensor data comprising the steps of: comparing said crop height detected by each said sensor relative to said cut height determined from said sensor data generated from said sensors, wherein said comparing of said crop height is performed for each said sensor and, if said crop height for a particular one of said sensors is greater than said cut height, said particular one of said sensors being an active sensor, or if said crop height for said particular one of said sensors is less than said cut height so as to indicate that crop stubble is being detected by said particular sensor, said particular one of said sensors being an ignored sensor; and operating said operating process in reliance upon only said sensor data of each said active sensor while ignoring said sensor data of each said ignored sensor.:

19. The method according to Claim 18, wherein said sensor data of said active sensors being usable by said operating process for a defined time period, with said sensor data of said ignored sensors being ignored by said operating process for said defined time period.

20. The method according to Claim 18, wherein said method further comprises the step of repeating said comparing of said crop height to determine whether said crop stubble is no longer present such that any said ignored sensor may be treated as an active sensor and determine whether crop stubble is now present such that any said active sensor may be treated as an ignored sensor.