Predicting grain tank levels when on slopes or hills

An embodiment includes a combine including a feeder housing for receiving harvested crop, a separating system for threshing the harvested crop to separate grain from residue, a grain tank for storing the separated grain, a grain tank level sensor for detecting a level of grain in the grain tank, an inclination sensor for detecting inclination of the combine, and a controller that controls the combine. The controller configured to receive the grain tank level from the grain tank level sensor, receive an inclination value from the inclination sensor, adjust the grain tank level based on the inclination value, and alert an operator of the adjusted grain tank level.

FIELD

The invention relates to grain tank measurement system and method for predicting grain tank levels when the combine is on slopes or hills.

BACKGROUND

Harvesters (e.g. combines) are used to harvest crops. Operations performed by conventional combines include chopping the crop and collecting grain in a grain tank. These conventional combines, however, utilize grain quantity measurement devices and methods that are susceptible to grain measurement inaccuracies and grain spillage, especially when the combine is harvesting on a slope or a hill.

SUMMARY

An embodiment includes a combine comprising a feeder housing for receiving harvested crop, a separating system for threshing the harvested crop to separate grain from residue, a grain tank for storing the separated grain, a grain tank level sensor for detecting a level of grain in the grain tank, an inclination sensor for detecting inclination of the combine, and a controller that controls the combine. The controller configured to receive the grain tank level from the grain tank level sensor, receive an inclination value from the inclination sensor, adjust the grain tank level based on the inclination value, and alert an operator of the adjusted grain tank level.

An embodiment includes a method for controlling a combine including a chassis, a feeder housing for receiving harvested crop, a separating system for threshing the harvested crop to separate grain from residue, a grain tank for storing the separated grain, a grain tank level sensor for detecting a grain level in the grain tank, an inclination sensor for detecting inclination of the combine, and a controller that controls the combine. The method comprising receiving, by the controller, the grain tank level from the grain tank level sensor, receiving, by the controller, an inclination value from the inclination sensor, adjusting, by the controller, the grain tank level based on the inclination value, and alerting, by the controller, an operator of the adjusted grain tank level.

DETAILED DESCRIPTION

Aspects of the invention provide methods and systems for operator adjustable tank level measurement for implementation in a harvester combine.

The terms “grain,” “straw,” and “tailings” are used principally throughout this specification for convenience but it is to be understood that these terms are not intended to be limiting. Thus “grain” refers to that part of the crop material which is threshed and separated from the discardable part of the crop material, which is referred to as non-grain crop material, material other than grain (MOG) or straw. Incompletely threshed crop material is referred to as “tailings.” Also the terms “forward,” “rearward,” “left,” and “right”, when used in connection with the agricultural harvester (e.g. combine) and/or components thereof are usually determined with reference to the direction of forward operative travel of the combine, but again, they should not be construed as limiting. The terms “longitudinal” and “transverse” are determined with reference to the fore-and-aft direction of the agricultural combine and are equally not to be construed as limiting.

Referring now to the drawings, and more particularly toFIG. 1A, there is shown one embodiment of an agricultural harvester in the form of a combine10, which generally includes a chassis12, ground engaging wheels14and16, a header18, a feeder housing20, an operator cab22, a threshing and separating system24, a cleaning system26, a grain tank28, and an unloading auger30.

Front wheels14are larger flotation type wheels, and rear wheels16are smaller steerable wheels. Motive force is selectively applied to front wheels14through a power plant in the form of a diesel engine32and a transmission (not shown). Although combine10is shown as including wheels, is also to be understood that combine10may include tracks, such as full tracks or half-tracks.

Header18is mounted to the front of combine10and includes a cutter bar34for severing crops from a field during forward motion of combine10. A rotatable reel36feeds the crop into header18, and a double auger38feeds the severed crop laterally inwardly from each side toward feeder housing20. Feeder housing20conveys the cut crop to threshing and separating system24, and is selectively vertically movable using appropriate actuators, such as hydraulic cylinders (not shown).

Threshing and separating system24is of the axial-flow type, and generally includes a rotor40at least partially enclosed by and rotatable within a corresponding perforated concave42. The cut crops are threshed and separated by the rotation of rotor40within concave42, and larger elements, such as stalks, leaves and the like are discharged from the rear of combine10. Smaller elements of crop material including grain and non-grain crop material, including particles lighter than grain, such as chaff, dust and straw, are discharged through perforations of concave42.

Grain which has been separated by the threshing and separating assembly24falls onto a grain pan44and is conveyed toward cleaning system26. Cleaning system26may include an optional pre-cleaning sieve46, an upper sieve48(also known as a chaffer sieve), a lower sieve50(also known as a cleaning sieve), and a cleaning fan52. Grain on sieves46,48and50is subjected to a cleaning action by fan52which provides an airflow through the sieves to remove chaff and other impurities such as dust from the grain by making this material airborne for discharge from straw hood54of combine10. Grain pan44and pre-cleaning sieve46oscillate in a fore-to-aft manner to transport the grain and finer non-grain crop material to the upper surface of upper sieve48. Upper sieve48and lower sieve50are vertically arranged relative to each other, and likewise oscillate in a fore-to-aft manner to spread the grain across sieves48,50, while permitting the passage of cleaned grain by gravity through the openings of sieves48,50.

Clean grain falls to a clean grain auger56positioned crosswise below and in front of lower sieve50. Clean grain auger56receives clean grain from each sieve48,50and from bottom pan62of cleaning system26. Clean grain auger56conveys the clean grain laterally to a generally vertically arranged grain elevator60for transport to grain tank28.

Tailings from cleaning system26fall to a tailings auger trough64. The tailings are transported via tailings auger64and return auger66to the upstream end of cleaning system26for repeated cleaning action. A pair of grain tank augers68at the bottom of grain tank28convey the clean grain laterally within grain tank28to unloading auger30for discharge from combine10.

The non-grain crop material proceeds through a residue handling system70. Residue handling system70includes a chopper, counter knives, a windrow door and a residue spreader. When combine10operating in the chopping and spreading mode, the chopper is set to a relatively high speed (e.g. 3,000 RPM), the counter knives may be engaged, the windrow door is closed and the residue spreader is running (e.g. rotating). This causes the non-grain crop material to be chopped in to pieces of approximately 6 inches or less and spread on the ground in a fairly uniform manner. In contrast, when combine10is operating in the windrow mode, the chopper is at a relatively low speed (e.g. 800 RPM), the counter knives are disengaged and the windrow door is open. The residue spreader may continue operation to spread only the chaff, with the crop material passing through the passageway created by the open windrow door.

The grain that is collected is measured to determine if the grain tank is full or not. The level of grain in grain tank28may be measured by different methods using different types of sensors. These sensors are positioned within grain tank28at locations suitable to measure the grain tank level.

In one example, a grain tank level sensor29positioned within grain tank28. Grain tank level sensor29may be an acoustic sensor, radar sensor or the like that measures distance to the grain in the tank. Generally, tank level sensor29transmits a signal towards the bottom of grain tank28and receives a reflection signal from the grain. A controller uses the roundtrip travel time of the signal to compute the distance from the sensor to the pile of grain. The controller uses this distance to determine how much grain is in grain tank28at any given time. As the grain pile grows, the roundtrip travel time of the signal will decrease indicating that the grain is getting closer to the top of grain tank28.

In another example, grain tank level sensors31A and31B are positioned within grain tank28. Grain tank level sensors31A and31B may be pressure switches that are triggered when they come into contact with the grain pile. Sensor31B is placed lower in the tank than is sensor31A, so as to detect when the grain tank is partially full (e.g. 50%, 75%, etc.). Sensor31A is placed near the top of the grain tank so as to detect when the grain tank is almost completely full (e.g. 100%). When the grain pile triggers sensor31B, the controller determines that the grain tank is partially full to a certain level (e.g. 75% full). When the grain touches sensor31A, the controller determines that the grain tank is completely full. Notifications may be made to the operator when these levels are detected.

Although not shown, in yet another example, grain tank level sensors29,31A and/or31B may be positioned on a grain tank extension. The grain tank extension could be a metal arm that extends above the grain tank. This would allow grain tank level sensors29,31A and/or31B to be positioned a set distance above the top of the grain tank. The operation of grain tank level sensors29,31A and/or31B in this example would remain the same as described above.

The detection of sensors29or31A and31B is dependent on the slope of the ground that the combine is traveling on. On level ground, the detected levels are generally accurate due to a uniform grain pile in the tank. However, when the combine is harvesting on a slope or a hill, the levels detected by sensors29,31A and31B may not be accurate due to the slope of a non-uniform grain pile in the tank. This is problematic, because if the actual level of the grain in the tank is higher than the level indicated by sensors29,31A and31B, there is a chance that grain can overflow and spill out of the top of the grain tank. Such spillage results in lost revenue and should be avoided.

In order to avoid spillage on slopes and hills, the combine also includes an inclination sensor33that may be mounted anywhere on the combine, including in the operator cabin as shown inFIG. 1A. Inclination sensor33is a dual axis sensor that detects inclination magnitude and direction over a 360° operating range. This information is then used to determine the actual grain level in the tank which may be different than the level indicated by sensors29,31A and31B. This process is described in more detail with references to later figures.

The combine inFIG. 1Ais one configuration of a combine setup for performing harvesting. However, other configurations are possible. For example.FIG. 1Billustrates a perspective view of a combine that utilizes a grain cart110for storing the harvested grain. As shown atFIG. 1B, combine100includes grain tank102for storing grain and unload tube108for carrying grain from grain tank102to grain cart110when tank level sensor29detects that the grain has reached a certain level. Combine100includes a controller104in cab106and transceiver116. Grain cart110may also include a transceiver114for communicating with combine transceiver116, tank level sensor112and load cell sensor118. In some embodiments, exemplary controllers may be placed at different locations within the cab or other locations on the combine.

In the example ofFIG. 1B, the level of grain in grain tank102is detected by tank level sensor29or by sensors31A and31B depending on the configuration, while the level of grain in grain cart110is detected by tank level sensor112(e.g. similar to sensor29or sensors31A and31B). The controller may control the combine to send grain from grain tank102to grain cart110, and measure both levels to ensure that grain does not spill either from grain tank102or grain cart110.

FIG. 2Ashows a close-up view of the sensors for the grain tank28fromFIG. 1A, where the combine is harvesting on level ground. During operation, grain is harvested and stored in grain tank28. As shown by the dashed line inFIG. 2A, the grain pile is fairly uniform (e.g. level with respect to the top of the grain tank) due to the level ground.

In one example, tank level sensor29transmits a signal that is reflected by the pile of grain. The round trip time of this signal is then used along with the known velocity (e.g. speed of light or speed of sound) of the transmitted signal to determine a distance from tank level sensor29to the pile of grain. This distance correlates to distance D1from the grain pile to the top opening of the grain tank.

In another example, pressure switch31B transmits a signal to the controller in response to being contacted by the grain pile. This indicates to the controller, that the grain has reached sensor31B located at a predetermined location (e.g. 75% up the wall of the grain tank). The controller therefore determines that the grain tank is partially (e.g. 75%) full.

In the example shown inFIG. 2A, the highest point (closest to the top of the tank) of the grain pile is denoted as D2. Distance D1detected by sensor29and distance D3detected by sensor31B therefore represent an accurate distance from the top (e.g. highest point) of the grain pile to the top opening of the grain tank so that the operator can determine if grain spillage might occur (e.g. D1and D3=actual distance D2). If the grain is not near the top of grain tank28, then the operator can continue harvesting. If, however, the grain is near the top of grain tank28, then the operator would stop harvesting and unload the collected grain to avoid spillage.

The distances D1and D2from the sensors29and31B to the grain pile, however, does not always directly correlate to the distance from the top of the grain pile to the top opening of the grain tank. In some scenarios (e.g. in sloped terrain), the grain pile tends to shift in a non-uniform manner where the highest portion of the grain pile is not oriented in the center of the grain tank under the sensor, but rather towards the tank walls.

In one example,FIG. 2Bshows a grain pile where the highest point of the pile is oriented towards the back portion of the grain tank. This may occur when the combine is traveling uphill during harvesting. In one example, sensor29may incorrectly determine that larger distance D1is the distance from the top (e.g. highest point) of the grain pile to the top of the grain tank, when the actual distance is only D2which is smaller than D1. In another example, sensor31B does not even detect the grain pile yet, even though the grain pile is only a small distance D2from the top of the grain tank. In this example, the controller will incorrectly determine that the grain tank is not even partially (e.g. 75%) full yet. Such errors in grain level detection may result in grain spillage if D2becomes zero.

In another example,FIG. 2Cshows a grain pile where the highest point of the pile is oriented towards the front portion of the grain tank. This may occur when the combine is traveling downhill during harvesting. In one example, sensor29may incorrectly determine that larger distance D1is the distance from the top (e.g. highest point) of the grain pile to the top of the grain tank, when the actual distance is only D2which is smaller than D1. In another example, sensor31B detects the grain pile, but sensor31A does not yet detect the grain pile. In this example, the controller will incorrectly determine that the grain tank is partially (e.g. 75%) full at distance D3. Such errors in grain level detection may again result in grain spillage if D2becomes zero.

AlthoughFIGS. 2B and 2Cshow examples where the grain pile is slanted towards the back and the front of the grain tank, the grain pile may be sloped in any direction within the grain tank, including to the sides and the corners of the tank (e.g. in any 360° direction). In addition, the slope of the grain may shift during operation of the combine on rough or non-flat terrain. When the grain is sloped as shown inFIGS. 2B and 2C, the sensors may incorrectly indicate the level of grain in the grain tank. This can lead to spillage of grain in certain circumstances. For example, if the sensor determines that the distance from the grain to the tank opening is D1or D3when it is actually only D2, the operator may continue harvesting and spill grain (e.g. grain spills out of the top of the grain tank and revenue is lost).

In order to avoid such spillage, the combine of the present system adjusts the grain tank level detected by the sensors to reflect a more accurate representation of the grain tank level. Determining the adjustment may be based on the various factors (e.g. inclination, crop type, etc.), and may can be performed by a controller in the combine, or via a personal computer (PC) remote from the combine. This adjusted grain tank level is then used to alert the operator to avoid spillage.

FIG. 3shows an example of a system300for controlling the combine. The system300includes an interconnection between a control system310of combine10, a remote PC306and a remote server302through network304(e.g. Internet). It should be noted that combine10does not have to be connected to other devices through a network. The controller of combine10can be a standalone system that receives operating instructions (e.g. tank level instructions such as alert levels, shifted operating ranges, etc.) through a user interface, through a removable memory device (e.g. Flash Drive) or from a server302via transceiver317(e.g. Wi-Fi, Bluetooth, Cellular, etc.).

Prior to operating combine10, an operator may designate the tank level alerts and other tank level related instructions (e.g. tank level alerts, shifted operating ranges, terrain, etc.). In one example, the operator uses interface311of the combine control system or PC306located at a remote location. Interface311and PC306allow the operator to view locally stored parameters from memory device315and/or download parameters from server302through network304. The operator may select (via Interface311or PC306) appropriate tank level related instructions based on various factors including, among others, the type of crop to be harvested by the combine, and the terrain. Once the tank level related instructions are selected, the operator can begin harvesting. Combine controller312then controls actuators314(e.g. thresher, chopper, etc.) based on the instructions. For example, sensors316(e.g. tank level sensor and inclination sensor) may be used during harvesting to more accurately determine the grain level to avoid spillage. Harvesting may also be tracked and aided by GPS receiver313to monitor terrain.

For example, if the terrain includes slopes and/or hills, the direction and magnitude of the slope is measured by inclinometer33. Controller312may use this inclination information along with other information (e.g. crop type) to estimate a more accurate grain tank level that more accurately represents the actual distance D2from the highest point of the grain pile to the top opening of the grain tank as shown inFIGS. 2B and 2C.

FIG. 4Ashows a data plot of inclination angle (e.g. slope) detected by inclination sensor33versus the actual angle (e.g. slope) of the grain pile in the grain tank for three different types of grain. Naturally, the grain pile angle increases as the inclination angle of the combine increases. This is true for most grains. However, some grains, due to oils and other physical properties may pile at a steeper slope than other grains for a given combine angle. For example, as shown inFIG. 4A, grain type 1 exhibits a relatively low grain pile slope as long as the inclination slope of the combine is below 4°. The same is true of grain types 2 and 3 as long as the inclination slope of the combine is below 6° and 8° respectively. However, when the inclination slope of the combine reaches certain levels (e.g. 4°, 6° and 8°) the grain pile slopes increase significantly. In general, grain slope for different grain types may exhibit linear or non-linear behaviour in response to inclination slope of the combine. Thus, it is beneficial for controller312to know the type of grain being harvested, to more accurately determine the highest point of the grain pile.

The inclinometer may be a dual-axis inclinometer capable of detecting an angle of inclination in a 360° direction and its magnitude (e.g. how steep).FIG. 4Bshows a graphical representation of a 360° inclinometer output. As shown, the inclinometer may detect inclines in the directions of the fore, aft, left and right sides of the combine, and any direction in between. An example 400 is provided inFIG. 4Bfor clarity. Specifically, vector406represents an incline detected by the inclinometer as the combine is traveling downhill. Vector406has a direction and a magnitude. The direction is 40° to the left of the fore of the combine (i.e. the combine is tilted towards the front and left). The magnitude of the vector indicates that the slope of the incline is 8°, which is almost halfway in between the minimum slope402of 0°, and the maximum slope404of 20°. This inclination information, therefore indicates to the controller312that the combine is tilted at a slope of 8° in a 40° direction towards the front and left of the combine. This information may then be used by controller312to estimate the highest point of the grain in the tank, and adjust the level output by the sensor.

FIG. 5shows a flowchart500describing the controller operation for adjusting the detected grain tank level and alerting the operator to avoid spillage. In step501controller312uses inclination sensor33to determine the direction and magnitude of the combine inclination. In step502, controller312uses the grain tank sensor(s)316(e.g.31A,31B, or29) to determine the grain tank level (e.g. distance remaining to top of grain tank, percentage full, etc.).

Once the inclination and grain tank level values are determined, controller312then adjusts the grain tank level in step503to estimate a more accurate value of the grain tank level. This adjustment may be performed using a number of different methods using the inclination value, grain tank level and optionally the crop type.

A first example is now described when pressure sensors31A and31B are installed in the combine grain tank. During operation, controller312monitors the inclination of the combine using sensors316. When pressure sensor31B (e.g. 75% full sensor) is triggered by the grain, controller312estimates the slope of the grain in tank. This may be performed by a table lookup where the inclination value correlates to a predetermined slope of the grain pile. The slope of the grain pile and the measured grain tank level are used to determine a line (see the dotted line inFIG. 2C) that intersects the grain tank wall at two points. The highest intersection point is determined to be the highest point of the grain pile. After pressure sensor31B is triggered, the grain pile level is not known until pressure sensor31A is triggered. To deal with this “blind spot” throughput may be monitored over time to estimate growth of the grain pile. This estimated growth, along with the measured inclination may then be used to estimate the intersection points of the line representing the surface of the grain pile.

A second example is now described when ultrasonic sensor29is installed in the combine grain tank. During operation, controller312monitors the inclination of the combine, and sensor29determines the distance to the grain. Based on these values, controller312estimates the slope of the grain pile in tank. Similar to the first example, this may be performed by a table lookup where the inclination value correlates to a predetermined slope of the grain pile. The slope of the grain pile and the measured grain tank level are used to determine a line (see the dotted line inFIG. 2C) that intersects the grain tank wall at two points (high point and low point). The high intersection point is determined to be the highest point of the grain pile. As the grain pile grows, sensor29continues to detect the level of the pile, and inclination sensor continuously monitors the inclination of the combine. With this continuous measurement, the highest point of the pile can continuously be estimated.

After the grain tank level is adjusted based on inclination, it is determined if the grain is at risk of spilling out of the grain tank. In step504, controller312makes this determination. If the adjusted grain level is determined to be less than a predetermined spill level, the level is simply displayed to the operator and harvesting continues in step506. If, however, the adjusted grain level is determined to greater than or equal to the predetermined spill level, an alert (e.g. via interface311) is issued to the operator in step505.

Regardless of the method for performing the adjustment of the grain level, the operator is notified of the estimated grain level and alerted when there is a risk of spillage. This process helps avoid spillage when harvesting on uneven ground and therefore reducing lost revenue. The alert may be given by sounding an audible or visual alarm. This may be accomplished by interface311, a dedicated bell/buzzer (not shown), an indicator light (not shown), etc.

The steps of adjusting the grain tank level based on inclination shown in steps501-506ofFIG. 5are performed by control system310including controller312upon loading and executing software code or instructions which are tangibly stored on a tangible computer readable medium315, such as on a magnetic medium, e.g., a computer hard drive, an optical medium, e.g., an optical disc, solid-state memory, e.g., flash memory, or other storage media known in the art. Thus, any of the functionality performed by the controller312described herein, such as the steps shown inFIG. 5, are implemented in software code or instructions which are tangibly stored on a tangible computer readable medium. Upon loading and executing such software code or instructions by the controller312, the controller312may perform any of the functionality of the controller312described herein, including the steps shown inFIG. 5described herein.