Patent Description:
Many work machines have implements, headers, or the like that are capable of being repositioned relative to the work machine and, in turn, relative to the underlying surface. Work machines often have hydraulic systems that raise and lower the implement relative to the work machine and the underlying surface. Some work machines can further adjust the pitch, roll, yaw, and height of the implement with a hydraulic system. Adjusting the height, pitch, roll, and yaw of the implement allows the user to execute a work function, such as mowing, by orienting the implement in an ideal orientation for the conditions of the underlying surface.

Many work machines have visual indicators that identify the position of the implement relative to the work machine. These work machines have one or more linkage assembly that couple the implement to the work machine. Further, the visual indicator is often positioned on a portion of the linkage assembly that identifies the position of the implement relative to the work machine. In some cases, the user must exit the work machine or otherwise be positioned to observe the visual indicator to determine the orientation of the implement. The visual indicators can be difficult to use and require the user to stop the work machine and exit a cab to determine whether the implement is positioned in the proper orientation.

Other work machines have a sensor on a tilt cylinder of the implement. The sensor identifies the axial displacement of the tilt cylinder to further communicate to the user the tilt orientation of the implement. The tilt cylinder sensor is often coupled to an external part of the tilt cylinder and thus prone to being contacted or otherwise damaged during a work operation. Further, the tilt cylinder sensor typically only identifies the displacement of the tilt cylinder and not the attitude of the implement along multiple axes. <CIT> Al relates generally to control of an implement operably coupled to a body of a vehicle, and more particularly to the estimation of the attitude and position of the implement relative to the body of the vehicle. <CIT> and <CIT> are additional prior art examples of work machines.

One embodiment of the present disclosure is a work machine that has an implement coupled to the work machine and a first sensor coupled to the implement. The implement comprising a draper head or a rotary head. Wherein, the first sensor identifies the orientation of the implement along more than one axis. The work machine comprises a second sensor coupled to the work machine, wherein the orientation of the implement is identified by comparing the values of the first sensor with the values of the second sensor. The work machine further comprises a controller and an implement position system that couples the implement to the work machine. The controller manipulates the implement position system to reposition the implement relative to the work machine by comparing orientation date from the first sensor to orientation data from the second sensor (<NUM>). According to the invention, the controller manipulates the implement position system to follow a contour of an underlying surface when the first sensor identifies a prolonged movement of the implement and the second sensor does not identify a corresponding prolonged movement of the work machine.

In one example of this embodiment, the first sensor identifies the orientation of the implement relative to a calibrated position.

In another example of this embodiment, the first sensor identifies the position of the implement along both a pitch axis and a roll axis and is configured to identify the height of the implement above an underlying surface.

Yet another example has a calibration process wherein the first sensor establishes a desired position relative to an underlying surface.

In an embodiment, this example has a calibration process wherein the second sensor establishes a level position relative to an underlying surface.

Another example of this embodiment has a calibration process wherein the first sensor establishes a lowered position and a raised position and can identify a plurality of positions there between.

A non-claimed example discloses a method for identifying the orientation of an implement that includes providing a first sensor coupled to the implement, a controller, and a work machine, communicating, to the controller with the first sensor, an implement pitch position, an implement roll position, especially also an implement height position. In a further embodiment, the method further comprising providing a second sensor in communication with the controller and coupled to the work machine, wherein the second sensor communicates to the controller a work machine pitch position and a work machine roll position relative to an underlying surface. In another embodiment, the controller determines the position of the implement relative to the underlying surface by identifying the pitch position and the roll position of the work machine relative to the underlying surface and by identifying the pitch position and the roll position of the implement relative to the work machine. In yet another embodiment, the controller repositions the implement to follow a ground contour when the first sensor identifies a prolonged movement of the implement and the second sensor does not identify a prolonged movement of the work machine.

One example of this embodiment includes providing an implement position system that receives signals from the controller to reposition the implement, and storing a first position in the controller that corresponds with a first pitch position and a first roll position. Wherein the controller communicates with the first sensor to identify the implement pitch position and the implement roll position to selectively reposition the implement with the implement position system into the first position. In an embodiment, this example includes providing a second sensor in communication with the controller and coupled to the work machine, wherein the second sensor communicates to the controller a work machine pitch position and a work machine roll position relative to an underlying surface. In an embodiment, this example, the controller determines the position of the implement relative to the underlying surface by identifying the pitch position and the roll position of the work machine relative to the underlying surface and by identifying the pitch position and the roll position of the implement relative to the work machine.

In another example of this embodiment, the first sensor communicates a yaw position of the implement to the controller.

In yet another example of this embodiment, the first sensor communicates an acceleration of the implement to the controller. In an embodiment, this example includes storing an acceleration threshold in the controller, wherein when the acceleration of the implement exceeds the acceleration threshold the controller sends a command to disengage the implement.

A non-claimed example discloses an implement orientation system for a work machine that includes a work machine, an implement coupled to the work machine, a controller, a first sensor coupled to the work machine and communicating a work machine position to the controller, and a second sensor coupled to the implement and communicating an implement position to the controller. Wherein, the controller compares the implement position to the work machine position to identify the orientation of the implement with the underlying surface.

In an embodiment, the second sensor communicates a work machine pitch to the controller and the first sensor communicates an implement pitch to the controller. In a further embodiment, the controller compares the work machine pitch to the implement pitch to determine the position of the implement relative to the work machine. In a further embodiment, the implement orientation system further comprising an implement position system communicating with the controller to alter the orientation of the implement relative to the work machine to a desired position, wherein the desired position is input through a user interface. In a further embodiment, the controller positions the implement in the desired position with the implement position system by comparing the work machine position to the implement position. In another example of this embodiment, the first sensor can communicate a work machine pitch to the controller and the second sensor can communicate an implement pitch to the controller. In an embodiment, this example, the controller can compare the work machine pitch to the implement pitch to determine the position of the implement relative to the work machine.

Another example of this embodiment includes an implement position system communicating with the controller to alter the orientation of the implement relative to the work machine to a desired position, wherein the controller stores a work position, a raised position, and the desired position and the desired position is an operator input. In an embodiment, this example, the controller transitions the implement between the work position and the raised position with the implement position system by comparing the work machine position to the implement position.

With reference to <FIG>, an elevated perspective view of a work machine <NUM> with no head or implement coupled thereto is illustrated. The work machine <NUM> may have at least one power unit that provides mechanical, electrical, and hydraulic power to the work machine <NUM>. In one embodiment, the power unit provides power to rotate a pair of drive wheels <NUM> coupled to a frame <NUM> of the work machine <NUM>. The drive wheels <NUM> may rotate relative to the work machine <NUM> to allow the work machine <NUM> to traverse an underlying surface <NUM>. The work machine <NUM> may also define an axis of travel <NUM> disposed lengthwise through a central portion of the work machine <NUM>.

In addition to drive wheels <NUM>, the embodiment shown in <FIG> has a pair of swivel caster wheels <NUM>. The caster wheels <NUM> may pivot freely about a mount to allow the work machine <NUM> to rotate as directed by the powered drive wheels <NUM>. However, the particular configuration of the drive wheels <NUM> and caster wheels <NUM> should not be limiting. In a different embodiment, there may be no wheels at all. Rather, the power unit may provide power to a pair of tracks to allow the work machine to traverse the underlying surface. In yet another embodiment, the caster wheels <NUM> may not be swivel caster wheels but rather be wheels coupled to an axle and configured to be mechanically coupled to the power unit.

Regardless of how the work machine moves, the work machine <NUM> may also have a cabin <NUM> coupled to the frame <NUM>. The cabin <NUM> may house a plurality of controls that allow a user to control the various systems of the work machine <NUM>. In one non-exclusive embodiment, the plurality of controls allow the user to control mechanical, electrical, and hydraulic systems of the work machine <NUM>. Further, one non-exclusive example of the controls may be a user interface <NUM> (See <FIG>). The user interface <NUM> may be positioned in the cabin <NUM> and be a touch screen, one or more knobs or buttons, a lever, or any other known device capable of identifying a user input.

<FIG> more clearly illustrates mounting locations for a head or implement (head or implement not shown in <FIG> or <FIG>). More particularly, a first lift arm <NUM>, a second lift arm <NUM>, an upper bracket <NUM>, and an upper actuator <NUM> are shown in <FIG>. The first and second lift arm <NUM>, <NUM>, along with the upper bracket <NUM>, may be coupled to the implement to control both a height <NUM> (see <FIG>) of the head relative to the underlying surface <NUM> as well as the angle of the head relative to the work machine <NUM>.

In one embodiment, each lift arm <NUM>, <NUM> may be pivotally coupled to the work machine <NUM> at a first pivot <NUM>. The first pivot <NUM> may be located at a proximal portion of each lift arm <NUM>, <NUM> relative to the frame <NUM>. Further, each lift arm <NUM>, <NUM> may extend away from the first pivot <NUM> towards a front end <NUM> of the work machine <NUM>. Each lift arm <NUM>, <NUM> may have a first coupler <NUM> defined at a distal end of the respective lift arm <NUM>, <NUM>. Each lift arm <NUM>, <NUM> may also have a second coupler <NUM> coupled to the respective lift arm <NUM>, <NUM> at a location between the first pivot <NUM> and the first coupler <NUM>. In one embodiment, the second coupler <NUM> may have a latching mechanism <NUM> coupled thereto that can be disposed in either a latch position or a release position.

A first and second float cylinder <NUM>, <NUM> may be coupled between the frame <NUM> and the first and second lift arms <NUM>, <NUM> respectively. More specifically, at least one link arm <NUM> may be pivotally coupled to each lift arm <NUM>, <NUM> on one end and to a cam pivot arm <NUM> on the other. The cam pivot arm <NUM> may be coupled to a lift arm axle <NUM> that may be rotated by a lift cylinder <NUM>. When the lift cylinder <NUM> rotates the lift arm axle <NUM>, the pivot arm <NUM> may rotate therewith and adjust the position of the respective lift arm <NUM>, <NUM>, with the respective link arm <NUM>. In one aspect of this disclosure, the orientation of the lift cylinder <NUM> may control, in part, the height <NUM> of the implement relative to the underlying surface <NUM>.

While one example of a lift cylinder <NUM> is illustrated, this disclosure considers any known method of manipulating the position of an implement relative to a work machine. More specifically, in other embodiments the float cylinders <NUM>, <NUM> may be actuators that are selectively repositioned by a controller <NUM> (see <FIG>) independent of one another. In this configuration, the float cylinders <NUM>, <NUM> can raise each of the lift arms <NUM>, <NUM> at the same time or selectively raise each of the lift arms <NUM>, <NUM> independently of one another. Accordingly, the orientation of the implement may be varied through at least the float cylinders <NUM>, <NUM> and the lift cylinder <NUM>.

In one embodiment, the lift cylinder <NUM> pivots the lift arms <NUM>, <NUM> between a raised position and a lowered position. The lift cylinder <NUM> may also allow for adjusting the height <NUM> of the head when the head is in the lowered position. In this embodiment, the lift cylinder <NUM> may control the height <NUM> of the head relative to the underlying surface <NUM> while the float cylinders <NUM>, <NUM> may be coupled to each lift arm <NUM>, <NUM> to provide dampened resistance when the head encounters a movement force. More specifically, the float cylinders <NUM>, <NUM> may provide a biasing force on the lift arms <NUM>, <NUM> away from the underlying surface <NUM>. When the lift arms <NUM>, <NUM> are coupled to the head, the lift cylinder <NUM> may position the head the desired height away from the underlying surface. The float cylinders <NUM>, <NUM> may provide the biasing force on the lift arms <NUM>, <NUM> so the head may more easily rise relative to the underlying surface <NUM> if it contacts an obstacle thereon. Further, the float cylinders <NUM>, <NUM> may allow the user to adjust the biasing force of the head relative to the underlying surface by increasing or decreasing a float cylinder force of the respective lift arms <NUM>, <NUM>.

In one embodiment, the link arm <NUM> may be pivotally coupled to the cam pivot arm <NUM> by a pin disposed in a slot of the link arm <NUM>. The slotted engagement allows the lift cylinder <NUM> to transition the lift arms <NUM>, <NUM> to a lowered position (where the pin is at an uppermost portion of the slot) and allow the float cylinders <NUM>, <NUM> to provide the biasing force to the head to allow the head to move away from the underlying surface should it contact an obstacle thereon. More specifically, when the pin is in the upper portion of the slot, and the head contacts an obstacle along the underlying surface, the float cylinders <NUM>, <NUM> can provide the biasing force to assist raising the head over the underlying obstacle. Further, as the head is raised over the underlying obstacle, the pin may transition towards a lower portion of the slot. Once the obstacle has been fully traversed, the pin may return to the top portion of the slot and the height <NUM> of the head may be maintained by the cylinder <NUM>.

Referring now to <FIG>, the work machine <NUM> is illustrated with an implement <NUM> such as a draper head coupled thereto. The implement <NUM> may be coupled to the work machine <NUM> by the second coupler <NUM> of the respective first and second lift arm <NUM>, <NUM>. Further, the implement <NUM> may also be coupled to the upper bracket <NUM> through the upper link <NUM>. In one embodiment, the upper link <NUM> may be a hydraulic cylinder that may be selectively actuated by the user through the plurality of controls. The upper link <NUM> may be pivotally coupled to the upper bracket <NUM> on a base end and pivotally coupled to a head mount of the implement <NUM> on a head end.

In one embodiment, the controller <NUM> may selectively actuate the upper link <NUM> to alter the orientation of the implement <NUM>. In this embodiment, if the upper link <NUM> is actuated to become longer, the implement <NUM> may change a pitch <NUM> as it rotates away from the work machine <NUM> about a pitch axis <NUM>. More specifically, as the upper link <NUM> extends, a portion of the implement <NUM> towards the front end <NUM> is moved towards the underlying surface. Alternatively, if the upper link <NUM> is actuated to become shorter, the implement <NUM> may rotate in an upward direction towards the work machine <NUM>. Further, as the upper link <NUM> contracts, a front end <NUM> portion of the implement <NUM> is pivoted away from the underlying surface <NUM>.

Referring now to <FIG>, the work machine <NUM> is illustrated with a rotary head <NUM> implement coupled thereto. The rotary head <NUM> may be coupled to the work machine <NUM> through the lift arms <NUM>, <NUM> and the upper link <NUM> similarly to the implement <NUM>. Further, the term implement used herein may be referring to any type of implement or header known in the art and the examples presented are not meant to be exhaustive.

<FIG> more clearly shows how the rotary head <NUM> is coupled to the work machine <NUM>. More specifically, the upper link <NUM> may pivotally couple the upper bracket <NUM> to a rotary bracket <NUM>. The upper link <NUM> may control the angular orientation of the rotary head <NUM> relative to the underlying surface in a similar manner as described in more detail above for the implement <NUM>. Accordingly, the features described above for the upper link <NUM> are equally applicable here and are considered incorporated herein for the rotary head <NUM> as well.

Referring now to <FIG>, the first coupler <NUM> is shown pivotally coupled to the rotary head <NUM>. In one embodiment, the first coupler <NUM> can couple to the rotary head <NUM> without contacting the second coupler <NUM>.

In one aspect of this disclosure, a single implement sensor <NUM> (or first sensor <NUM>) may be coupled to the implement <NUM> to identify the orientation of, and forces experienced by, the implement <NUM>, <NUM>. The implement sensor <NUM> may be an inertial measuring unit that has a three axis microelectromechanical system accelerometer and a three axis microelectromechanical gyroscope. The implement sensor <NUM> may be configured to identify the orientation of the implement <NUM> such as the pitch <NUM> about the pitch axis <NUM>, a roll <NUM> about a roll axis <NUM>, and a yaw <NUM> about a yaw axis <NUM>. Further, the first sensor <NUM> may identify acceleration values experienced by the implement <NUM>. The single implement sensor <NUM> may be positioned at a location on the implement that is substantially protected from exposure to harmful debris.

In one aspect of this disclosure, the pitch <NUM>, yaw <NUM>, and roll <NUM> of the implement <NUM> may all be controlled by an implement position system <NUM>. The implement position system <NUM> may be controlled by one or more controller <NUM> to manipulate one or more of the float cylinders <NUM>, <NUM>, the upper link <NUM>, and the lift cylinder <NUM> to reposition an implement coupled thereto. More specifically, one embodiment considered herein allows the roll of the implement <NUM> to be modified by raising the first lift arm <NUM> with the first float cylinder <NUM> while maintaining the position of the second lift arm <NUM> with the second float cylinder <NUM> or vice versa. Similarly, the pitch of the implement <NUM> may be manipulated by the implement position system <NUM> by modifying the length of the upper link <NUM> with the controller <NUM>. In yet another example, the first and second lift arms <NUM>, <NUM> may be a first lift arm length cylinder <NUM> and a second lift arm length cylinder <NUM> that are actuators in communication with the controller <NUM> and configured to change orientation to modify the yaw <NUM> of the implement <NUM> among other things.

While a particular type of implement position system <NUM> is shown and described herein, this disclosure considers any type of implement position system known in the art. More specifically, a common three-point hitch assembly may implement the teachings of this disclosure. For example, the three-point hitch assembly may have three actuators in communication with a controller to reposition the height <NUM> of the implement relative to the underlying surface <NUM>. Further, the three-point hitch may utilize three actuators to reorient an implement coupled thereto in any one or more of the yaw <NUM>, pitch <NUM>, or roll <NUM> directions.

Similarly, a single work machine sensor <NUM> (or second sensor <NUM>) may be coupled to the work machine <NUM> to identify the orientation and forces experienced by the work machine <NUM>. The work machine sensor <NUM> may also be an inertial measuring unit that has a three axis microelectromechanical system accelerometer and a three axis microelectromechanical gyroscope. The work machine sensor <NUM> may be configured to identify a pitch <NUM> about a pitch axis <NUM>, a roll <NUM> about a roll axis <NUM>, and a yaw <NUM> about a yaw axis <NUM>. Further, the work machine sensor <NUM> may identify acceleration values experienced by the work machine <NUM>. In one non-exclusive example, the work machine sensor <NUM> is coupled to the frame <NUM> of the work machine <NUM>.

Referring now to <FIG>, a schematic view of several components described herein is illustrated. More specifically, the orientation of the components of the implement position system <NUM> may be selectively altered by one or more controller <NUM>. The controller <NUM> may be a single controller that has a processor and a memory unit stored thereon or the controller may access a memory unit or processor located remotely therefrom. Further still, in another embodiment considered herein multiple controllers implement the teachings of this disclosure. Further still, in one embodiment a remote user interface <NUM> may act as the controller <NUM> to execute the functions described herein.

Regardless of the type or location of the controller <NUM>, the controller <NUM> may selectively alter the orientation of the implement <NUM> with the implement position system <NUM>. More specifically, an electro-hydraulic system, electro-pneumatic system, or an electrical system may selectively reposition corresponding actuators. For example, the electro-hydraulic and electro-pneumatic systems may have a plurality of hydraulic or pneumatic valves that are repositionable by the controller <NUM> via an electrical system to provide varying fluid flows and pressures to the actuators. Similarly, electrical systems may have electrical actuators that are repositioned by the controller <NUM> to alter the orientation of the implement <NUM>. Accordingly, this disclosure considers using any known method for manipulating the implement <NUM> with the implement position system <NUM>.

Whether the implement position system <NUM> uses hydraulic, pneumatic, or electrical power to reposition the implement <NUM>, the implement <NUM> may be movable in each of the pitch <NUM>, roll <NUM>, and yaw <NUM> directions via the implement position system <NUM>. In one non-exclusive example, the controller <NUM> may move the implement in the roll position by altering the length of only one of the float cylinders <NUM>, <NUM>. Similarly, the controller <NUM> can move the implement in the pitch direction <NUM> by altering the length of the upper link <NUM>. Further still, the controller <NUM> can move the implement in the yaw direction <NUM> by altering the length of the first lift arm <NUM> with the first lift arm length cylinder <NUM> or by altering the length of the second lift arm <NUM> with the second lift arm length cylinder <NUM>.

While one particular implement position system <NUM> is shown and described herein, this disclosure considers using other embodiments as well. More specifically, in one embodiment the implement position system may be a three linkage coupler that couples the implement to the work machine. Each of the three linkages may be an actuator that has a variable length controlled by the controller <NUM>. In this configuration, the controller <NUM> can alter the lengths of the three linkages to manipulate the implement in the pitch, roll, and yaw directions <NUM>, <NUM>, <NUM>. Accordingly, any known implement positioning system is considered herein as being movable by the controller <NUM> as described herein.

Referring now to <FIG>, one non-exclusive example of an implement position logic <NUM> is illustrated. The implement position logic <NUM> may utilize the implement sensor <NUM>, the implement position system <NUM>, and the controller <NUM> to selectively control the position of the implement <NUM>, <NUM>. More specifically, the implement position logic <NUM> may be selectively initiated in box <NUM>. The implement initiation box <NUM> may be selectively initiated by a user via the user interface <NUM> or automatically initiated by the controller <NUM> based on the conditions of the work machine. For example, the user interface <NUM> may have an option for the user to start the implement orientation process such as a push button, an icon on a touch screen, a voice command, or any other known user interface selection method. Alternatively, the controller <NUM> may initiate box <NUM> when the work machine <NUM> is turned to a run position or the like.

Regardless of the method used to start the implement orientation process of box <NUM>, in box <NUM> the user may be instructed or otherwise prompted to position the implement on a calibration surface. In one non-exclusive example, the user interface <NUM> may be used to instruct the user to position the implement on a calibration surface. Alternatively, in one embodiment box <NUM> may be an assumed condition when the start implement orientation process <NUM> is initiated. Accordingly, in at least one embodiment box <NUM> may be part of box <NUM>.

In box <NUM> the controller <NUM> may establish at least one calibrated or reference position of the implement. In one non-exclusive example, the calibrated position may be the position in which the implement is resting on the underlying surface. In another example, the reference position may be determined relative to an external source such as a base station sensor or the like. Further, in one aspect of this disclosure the user interface <NUM> may continue to instruct the user to position the implement on a level surface during box <NUM>. In one example of this disclosure, box <NUM> may include storing multiple calibrated positions. More specifically, in addition to storing the position data from the implement sensor <NUM> when the implement is resting on the underlying surface, the controller <NUM> may also move the implement to a fully raised position and store position data from the implement sensor <NUM> in the fully raised position as well. Further still, the controller <NUM> may move the implement to any orientation and store the position data therein as part of box <NUM>.

A level, flat surface may be recommended during box <NUM>, but this disclosure may implement the teachings described herein regardless of the orientation of the underlying surface as long as the work machine and implement are oriented in substantially the same way relative to the underlying surface. That is to say, as long is the underlying surface is relatively planar, the box <NUM> may be effectively executed even if the surface is not level.

The controller <NUM> may establish the calibrated position or positions in box <NUM> by allowing the implement position system <NUM> to be positioned in a neutral state wherein any actuators or the like are not powered. In the neutral state, the implement <NUM>, <NUM> may fall to the underlying surface responsive to the gravitational force acting on the implement. More specifically, if the implement position system is hydraulic or pneumatic, any cylinders utilized therein may not be pressurized and allowed to reposition as the implement falls to the underlying surface. Similarly, if the implement position system <NUM> utilizes electrical actuators they may not be powered in box <NUM> to allow the implement to become positioned along the underlying surface. Alternatively, the actuators of the implement position system <NUM> may be powered to direct the implement to a ground position in box <NUM>, <NUM>.

In box <NUM>, the controller <NUM> may utilize the implement sensor <NUM> to identify and store calibrated position values of the implement. More specifically, if the implement sensor <NUM> is an inertial measuring unit described above, the controller <NUM> may identify a pitch position about the pitch axis <NUM>, a roll position about the roll axis <NUM>, and a yaw position about a yaw axis <NUM> in box <NUM>. The controller <NUM> may gather and store the corresponding position utilizing the three axis microelectromechanical system accelerometer and the three axis microelectromechanical gyroscope of the implement sensor <NUM>. The stored positions may be utilized by the controller <NUM> to identify the orientation of the implement <NUM>, <NUM> when it is contacting the underlying surface.

Further, the controller <NUM> may store a plurality of position data points for each orientation of the implement. For example, the controller <NUM> may store data points for each of the pitch, roll, yaw, and height when the implement is on the underlying surface and also store data points for the pitch, roll, yaw, and height when the implement is in a fully raised position. Further still, the controller <NUM> may store data points for any other orientation of the implement <NUM>, <NUM>.

Next, in box <NUM>, the controller <NUM> may identify the desired implement position from the user interface <NUM>. More specifically, the user interface <NUM> may have selections for the height of the implement above the underlying surface, yaw of the implement, pitch of the implement, and roll of the implement among other things. Alternatively, the user interface <NUM> may have preset implement orientations stored therein where the height, yaw, pitch, and roll are all established based on a preset selection. In one non-exclusive example, the desired implement position may be any position between the position identified when the implement is on the ground and the fully raised position identified in box <NUM>.

In one non-exclusive example of this disclosure, the controller <NUM> may establish threshold values based on the desired implement position in box <NUM>. For example, the controller <NUM> may have preset tolerances above and below the desired implement position selected by the user. More specifically, if the user identifies a desired height of five inches, the controller may set a lower threshold height of about four inches and an upper threshold of about six inches as one non-exclusive example. Similarly, the desired implement position may correspond with a pitch angle, a roll angle, and a yaw angle. The controller <NUM> may also establish upper and lower thresholds that correspond with the pitch, roll, and yaw angles identified. For example, the upper angle threshold may be one degree greater than the desired angle and the lower angle threshold may be one degree less than the desired angle.

While some specific threshold values are described herein, this disclosure considers utilizing threshold values that are greater than, and less than, those described. Further still, in one embodiment the user may select the threshold values with the user interface <NUM> instead of automatically deriving the threshold values from the desired implement position. Accordingly, this disclosure considers utilizing many different threshold values in box <NUM>.

In box <NUM>, the controller <NUM> may engage the implement position system <NUM> to reposition the implement to the desired implement position identified in box <NUM>. In this box, the controller <NUM> may utilize any one or more of the first lift arm float cylinder <NUM>, the second lift arm float cylinder <NUM>, the first lift arm length cylinder <NUM>, the second lift arm length cylinder <NUM>, the upper link <NUM>, or the lift cylinder <NUM> to reposition the implement to become oriented within the threshold values of the desired implement position. More specifically, in box <NUM> the controller <NUM> may continually monitor the implement sensor <NUM> as it manipulates the implement position system <NUM> towards the desired implement position established in box <NUM>.

In box <NUM>, the controller <NUM> determines whether the implement position is within the implement position threshold established in box <NUM>. More specifically, the controller <NUM> identifies the height, yaw angle, roll angle, and pitch angle with the implement sensor <NUM> by comparing the current sensor <NUM> readings to the calibrated position values of box <NUM>. In other words, in box <NUM> the controller <NUM> compares the identified values with the implement position threshold values. If the identified values are not within the threshold values compared to the calibrated position values, the controller <NUM> may repeats boxes <NUM>, <NUM>, and <NUM> until the identified values are within the threshold values. Once the identified values are within the threshold values in box <NUM>, the controller <NUM> may maintain the implement position with the implement position system <NUM> in box <NUM>.

Referring now to <FIG>, one non-exclusive example of an implement and work machine position logic <NUM> is illustrated. The implement and work machine position logic <NUM> may utilize the implement sensor <NUM>, the implement position system <NUM>, the work machine sensor <NUM>, and the controller <NUM> to selectively control the position of the implement <NUM>. More specifically, the implement and work machine position logic <NUM> may be selectively initiated in box <NUM>. The implement orientation box <NUM> may be selectively initiated by a user via the user interface <NUM> or automatically initiated by the controller <NUM> based on the conditions of the work machine as describe above for box <NUM>.

Regardless of the method used to start the implement orientation process of box <NUM>, in box <NUM> the user may be instructed or otherwise prompted to position the implement <NUM>, <NUM> and the work machine on a calibration surface. In one non-exclusive example, the user interface <NUM> may be used to instruct the user to position the implement on a calibration surface. Alternatively, in one embodiment box <NUM> may be assumed when the start implement orientation process <NUM> is initiated. Accordingly, in at least one embodiment box <NUM> may be part of box <NUM>. In one non-exclusive example, the calibration surface may be an underlying surface that is substantially level and flat.

In box <NUM> the controller <NUM> may establish one or more calibrated positions of the implement using the implement sensor <NUM> similar to box <NUM> described above. In one non-exclusive example, a first calibrated position may be the position in which the implement <NUM>, <NUM> is resting on the underlying surface <NUM> and a second calibrated position may be the position in which the implement is in a fully raised position. Further, in one aspect of this disclosure the user interface <NUM> may continue to instruct the user to position the implement on a level surface during box <NUM>. A level, flat surface may be recommended during box <NUM>, but this disclosure may implement the teachings described herein regardless of the orientation of the underlying surface as long as the work machine and implement are oriented in substantially the same way relative to the underlying surface. That is to say, as long is the underlying surface is relatively planar, the box <NUM> may be effectively executed even if the surface is not level.

Similarly, in box <NUM> the controller <NUM> may utilize the work machine sensor <NUM> to establish a calibrated position of the work machine. In one non-exclusive example, the calibrated position may be the position in which the work machine <NUM> is sitting on a flat surface. While a level underlying surface may be preferred, boxes <NUM> and <NUM> can be performed on a plane offset from level as well. In one aspect of this disclosure, the controller <NUM> uses the work machine sensor <NUM> to establish the planar orientation of the underlying surface.

In box <NUM>, the controller <NUM> may utilize the implement sensor <NUM> and the work machine sensor <NUM> to identify and store calibrated position values of the implement <NUM>, <NUM> and the work machine <NUM>. More specifically, if the implement sensor <NUM> is an inertial measuring unit described above, the controller <NUM> may identify a pitch position about the pitch axis <NUM>, roll position about the roll axis <NUM>, and yaw position about a yaw axis <NUM> in box <NUM>. The work machine sensor <NUM> may similarly be an inertial measuring unit described above and coupled to the chassis of the work machine <NUM>. In this configuration, the controller <NUM> may identify a pitch position about the pitch axis <NUM>, a roll position about the roll axis <NUM>, and a yaw position about a yaw axis <NUM> in box <NUM>. The controller <NUM> may gather and store the corresponding position data utilizing the three axis microelectromechanical system accelerometer and the three axis microelectromechanical gyroscope of the implement sensor <NUM> and the work machine sensor <NUM>. The stored positions may be utilized by the controller <NUM> to identify the orientation of the implement <NUM>, <NUM> and the work machine <NUM> when the implement is contacting the underlying surface, in the fully raised position, and in any other calibration position.

Next, in box <NUM>, the controller <NUM> may identify the desired implement position from the user interface <NUM> similar to box <NUM>. More specifically, the user interface <NUM> may have selections for the height of the implement above the underlying surface, yaw of the implement, pitch of the implement, and roll of the implement among other things. Alternatively, the user interface may have preset implement orientations stored therein where the height, yaw, pitch, and roll are all established based on a preset selection. In one aspect of this embodiment, the desired implement position may be determined by establishing offset values of the implement sensor <NUM> relative to the work machine sensor <NUM>.

In one non-exclusive example of this disclosure, the controller <NUM> may establish threshold values based on the desired implement position in box <NUM>. For example, the controller <NUM> may have preset tolerances above and below the desired implement position selected by the user as described above for box <NUM>.

Further, in one example of this embodiment the desired implement position may be an offset of the current work machine position. More specifically, the work machine sensor <NUM> may establish the current orientation of the underlying surface by communicating the roll <NUM>, pitch <NUM>, and yaw <NUM> of the work machine <NUM> to the controller <NUM>. Then the controller <NUM> can utilize the implement sensor <NUM> to ensure that the implement <NUM> remains in the desired implement position relative to the underlying surface. For example, if the user desires the implement to have an offset pitch angle relative to the underlying surface, the controller <NUM> may first determine the pitch angle of the underlying surface utilizing the work machine sensor <NUM> and then manipulate the implement with the implement position system <NUM> so that the pitch angle of the implement <NUM>, <NUM> relative to the underlying surface <NUM> is the offset pitch angle selected by the user. While pitch angle has been specifically described herein, this disclosure considers comparing the implement sensor <NUM> values to the work machine sensor <NUM> values for any of the pitch, yaw, roll, and height orientations.

In box <NUM>, the controller <NUM> may engage the implement position system <NUM> to reposition the implement to the desired implement position identified in box <NUM>. In this box, the controller <NUM> may utilize any one or more of the first lift arm float cylinder <NUM>, the second lift arm float cylinder <NUM>, the first lift arm length cylinder <NUM>, the second lift arm length cylinder <NUM>, the upper link <NUM>, or the lift cylinder <NUM> to reposition the implement <NUM>, <NUM> to become oriented within the threshold values of the desired implement position established in box <NUM>. Further, in box <NUM> the controller <NUM> may determine the current work machine attitude or orientation relative to the calibrated orientation with the work machine sensor <NUM>. Similarly, in box <NUM> the controller <NUM> may determine correction values of the current work machine attitude or orientation relative to the calibrated orientation of the work machine <NUM>. In other words, in box <NUM> the controller <NUM> may determine how much the orientation of the work machine <NUM> has changed relative to the calibrated position and assign attitude correction values thereto. The attitude correction values may be the difference between the calibrated position values and the work machine attitude identified in box <NUM>. Accordingly, in box <NUM> the controller <NUM> may continually monitor the work machine sensor <NUM> and the implement sensor <NUM> as it manipulates the implement position system <NUM> towards the desired implement position established in box <NUM>.

In box <NUM>, the controller <NUM> determines whether the implement position is within the implement position threshold established in box <NUM>. More specifically, the controller <NUM> identifies the height, yaw angle, roll angle, and pitch angle with the work machine sensor <NUM> and the implement sensor <NUM> and compares the identified values with the implement position threshold values. If the identified values are not within the threshold values, the controller <NUM> may repeat boxes <NUM>, <NUM>, <NUM>, <NUM>, and <NUM> until the identified values are within the threshold values. Once the identified values are within the threshold values in box <NUM>, the controller <NUM> may maintain the implement position with the implement position system <NUM> in box <NUM>.

Referring now to <FIG> one embodiment of a float pressure logic <NUM> is disclosed. In one embodiment of the implement position system <NUM>, the pressure provided to the float cylinders <NUM>, <NUM> may be altered by the controller <NUM> to provide a variable springed force to the lift arms <NUM>, <NUM> and thereby to any implement coupled thereto. The springe force provided by the float cylinders <NUM>, <NUM> may help the implement <NUM>, <NUM> pass over any obstacles it contacts on the underlying surface as described above. In one aspect of this disclosure, the float pressure logic <NUM> may utilize the implement sensor <NUM> to modify the float pressure and thereby the springed force applied by the float cylinders <NUM>, <NUM>.

Box <NUM> may initiate the implement acceleration monitoring process. Box <NUM> may be automatically initiated when the work machine is in an on state or it may be initiated by the user via the user interface <NUM>. Regardless of how the float pressure logic is initiated, once it is initiated the controller <NUM> may monitor the implement sensor <NUM> to determine the acceleration values experienced by the implement <NUM>, <NUM> in box <NUM>. More specifically, the controller <NUM> may utilize the three axis microelectromechanical system accelerometer of the implement sensor <NUM> to determine the acceleration values experienced by the implement <NUM>, <NUM>.

In box <NUM>, the controller <NUM> may compare the acceleration values identified in box <NUM> with acceleration threshold stored in the controller <NUM> or input therein through the user interface <NUM>. In one example of this embodiment, the acceleration thresholds may be ideal acceleration values that the implement would apply in an ideal work environment. Alternatively, the user may input the ideal acceleration values they would like applied to the implement via the float cylinders <NUM>, <NUM> by inputting the acceleration values through the user interface <NUM>.

Whether the threshold value is pre-set in the controller <NUM> or input by a user through the user interface <NUM> in box <NUM> the controller <NUM> may compare active acceleration values measured by the implement sensor <NUM> to the acceleration thresholds identified in box <NUM>. If the acceleration values are not within the threshold range, the controller <NUM> may adjust the float pressure in box <NUM>. More specifically, the controller <NUM> may increase or decrease the float pressure applied to the float cylinders <NUM>, <NUM> based on the acceleration values identified by the implement sensor <NUM>. However, if the acceleration values are within the threshold values in box <NUM>, the controller <NUM> may end this logic sequence or continue to compare the acceleration values to the threshold values in box <NUM>.

In yet another aspect of this disclosure, the acceleration values identified by the implement sensor <NUM> may be monitored by the controller <NUM> to determine when the implement has an extreme contact in box <NUM>. An extreme contact may occur when the implement hits a large rock, stump, or other obstruction on the underlying surface. In this example, when the implement sensor <NUM> identifies an extreme contact in box <NUM>, the controller <NUM> may adjust the working conditions of the implement in box <NUM>. In one non-exclusive example, this may include reducing power to the implement <NUM>, <NUM>, stopping the work machine <NUM>, or executing any other function to minimize the risk of damaging the work machine <NUM> or implement <NUM>, <NUM>.

Referring now to <FIG>, a side schematic view of a ground contour change is illustrated. In <FIG>, the work machine <NUM> is illustrated travelling in a forward direction <NUM> towards a grade change <NUM>. In the example of <FIG>, the grade change <NUM> may be an incline in the underlying surface <NUM>. However, the teachings of this disclosure may also be applied to declines and lateral changes in the underlying surface <NUM> as well. In the schematic view of <FIG>, the underlying surface is divided into a planar section <NUM>, a partial incline section <NUM>, and a full incline section <NUM>.

The planar section <NUM> may be representative of portions of a field or the like wherein the underlying surface <NUM> is substantially planar. In the planar section <NUM>, the implement <NUM>, <NUM> may be positioned as instructed by the implement position system <NUM>. That is to say, the underlying surface <NUM> is not altering the position of the implement <NUM>, <NUM> relative to the work machine <NUM> because both the implement <NUM>, <NUM> and the work machine <NUM> are positioned on the planar underlying surface <NUM>.

However, as the work machine travels in the forward direction towards the grade change <NUM>, the implement <NUM>, <NUM> moves into the partial incline section <NUM> before wheels <NUM> of the work machine <NUM>. In this situation, the implement <NUM>, <NUM> may have skids, wheels, or other ground contacting mechanisms that cause the implement <NUM>, <NUM> to move relative to the work machine <NUM> as the implement <NUM>, <NUM> travels along the partial incline section <NUM> while the work machine <NUM> remains on the planar section <NUM>.

As described herein, the implement <NUM>, <NUM> may be coupled to the work machine <NUM> with a plurality of linkages or the like that allow the implement <NUM>, <NUM> to move relative to the work machine <NUM>. In the embodiments illustrated herein, the lift arms <NUM>, <NUM> and upper link <NUM> are pivotally coupled to the work machine <NUM> to allow the implement <NUM>, <NUM> to raise and lower while substantially maintaining the tilt orientation or pitch <NUM> of the implement <NUM>, <NUM>. In the scenario illustrated in <FIG>, maintaining the pitch orientation of the implement <NUM>, <NUM> as it enters the partial incline section <NUM> may cause any cutting mechanisms or the like of the implement <NUM>, <NUM> to cut into the underlying surface <NUM>. In other words, when the implement <NUM>, <NUM> is in the partial incline section <NUM>, the implement <NUM>, <NUM> and the work machine <NUM> are no longer occupying a coplanar surface and the pitch <NUM> of the implement <NUM>, <NUM> may drive the implement <NUM>, <NUM> into the underlying surface <NUM> unless the pitch <NUM> is adjusted.

Referring now to <FIG>, one exemplary logic flowchart is illustrated that allows the controller <NUM> to adjust the implement position system <NUM> to address changes in the contour of the underlying surface <NUM>. More specifically, the controller <NUM> may monitor the implement sensor <NUM> and the work machine sensor <NUM> in box <NUM>. In the example of <FIG>, the controller <NUM> may compare the implement sensor <NUM> position to the work machine sensor <NUM> to identify the orientation of the work machine <NUM> and the implement <NUM>, <NUM>. As the implement <NUM>, <NUM> enters the partial incline section <NUM>, the controller <NUM> may identify a height change in the implement <NUM>, <NUM> relative to the work machine <NUM> as the implement <NUM>, <NUM> travels up the incline of the underlying surface <NUM>.

In one aspect of this disclosure, the controller <NUM> may utilize a filter or the like to manage readings from the work machine sensor <NUM> and implement sensor <NUM>. More specifically, the controller <NUM> may be filtering out signals that are indicative of short changes to the work machine <NUM> or implement <NUM>, <NUM> that are not caused by a substantial change in grade of the underlying surface <NUM>. As one non-exclusive example, the controller <NUM> may monitor the sensors <NUM>, <NUM> for prolonged changes and disregard short changes that may be caused by debris on the underlying surface <NUM> or the like. In box <NUM>, the controller <NUM> may monitor the implement sensor <NUM> to identify any prolonged movements of the implement <NUM>, <NUM>. A prolonged movement may be any movement that is sustained for a sufficient amount of time to be indicative of a grade change in the underlying surface <NUM> rather than debris.

In box <NUM>, if the movement identified by the implement sensor <NUM> is not prolonged, the controller <NUM> will determine that the movement was caused by debris or the like and return to box <NUM> to continue to monitor the sensors <NUM>, <NUM>. However, if the movement identified by the implement sensor <NUM> is prolonged, the controller <NUM> may check whether the work machine sensor <NUM> also experienced the movement in box <NUM>. In box <NUM>, the controller <NUM> may check whether the movement of the implement <NUM>, <NUM> was caused by movement of the work machine <NUM>. If the work machine sensor <NUM> indicates similar movement as the implement sensor <NUM>, the controller may conclude that no further action is required and continue to monitor the sensors <NUM>, <NUM> in box <NUM>.

However, if the controller <NUM> determines that the work machine <NUM> has not experienced similar movement in box <NUM>, the controller <NUM> may manipulate the position of the implement <NUM>, <NUM> with the implement position system <NUM> to address the movement of the implement <NUM>, <NUM>. More specifically, in the example of <FIG>, when the implement <NUM>, <NUM> is on the partial incline section <NUM> and the work machine <NUM> is on the planar section <NUM>, the controller <NUM> will have identified a prolonged change in the height of the implement <NUM>, <NUM> with the implement sensor <NUM> in box <NUM>. Further, the controller <NUM> will have checked the work machine sensor <NUM> and identified that the work machine <NUM> has not caused the movement of the implement <NUM>, <NUM> in box <NUM>. Accordingly, in this non-exclusive example of box <NUM>, the controller <NUM> may correlate the height increase of the implement <NUM>, <NUM> with an incline in the underlying surface <NUM>. Further, to avoid damaging the underlying surface and the implement <NUM>, <NUM>, the controller <NUM> may engage the upper link <NUM> to change the pitch <NUM> of the implement <NUM>, <NUM> to match the incline in the grade.

After the controller <NUM> has modified the orientation of the implement <NUM>, <NUM> in box <NUM>, the controller <NUM> may continue to monitor the work machine sensor <NUM> to determine when the work machine <NUM> has entered the grade change <NUM> in box <NUM>. More specifically, the controller <NUM> may repeatedly check the work machine sensor <NUM> to identify when the work machine <NUM> is on the grade change <NUM>. As the work machine <NUM> enters the grade change <NUM>, the work machine sensor <NUM> will indicate the prolonged movement of the work machine <NUM> as the wheels <NUM> enter the partial incline section <NUM>. Further, as the wheels <NUM> travel up the partial incline section <NUM>, the work machine <NUM> and the implement <NUM>, <NUM> may both occupy the grade change <NUM> and be on a substantially coplanar portion of the underlying surface <NUM>.

Once the controller <NUM> identifies that the work machine <NUM> has entered the grade change <NUM> in box <NUM>, the controller <NUM> may engage the implement position system <NUM> to return the implement to the desired implement position in box <NUM>. In other words, in box <NUM> the controller <NUM> may identify that the work machine <NUM> and implement <NUM>, <NUM> are occupying a substantially planar surface and will return the implement position to the desired implement position (i.e. the desired implement position established in <FIG>). After the implement <NUM>, <NUM> is returned to the desired position in box <NUM>, the controller <NUM> may return to box <NUM> and continue to monitor the sensors <NUM>, <NUM> for further grade changes.

While the embodiment shown and described herein for <FIG> and <FIG> refer to the work machine <NUM> approaching an incline in the underlying surface <NUM>, a person skilled in the art understands that the disclosed teachings can also be applied when the work machine <NUM> approaches a decline in the underlying surface <NUM>. More specifically, when a decline in the grade is approached the controller <NUM> may identify a drop in the height of the implement <NUM>, <NUM> relative to the work machine <NUM>. The drop in height may be addressed by tilting the pitch <NUM> of the implement <NUM>, <NUM> forward to more closely follow the decline contour of the underlying surface <NUM> until the work machine <NUM> enters the decline as well. Accordingly, this disclosure contemplates utilizing the teachings discussed herein to manipulate the orientation of the implement <NUM>, <NUM> to address any prolonged change in the underlying surface <NUM> to allow the implement <NUM>, <NUM> to remain in the desired position relative to the underlying surface <NUM>.

While two different implements <NUM>, <NUM> are shown and described herein, this disclosure is not limited to these particular-style implements. Draper or rotary style heads are only a couple of the many potential types of heads that can be coupled to the work machine <NUM>. Accordingly, this disclosure should not be limited to any particular type of head.

Claim 1:
A work machine, comprising:
an implement (<NUM>, <NUM>) coupled to the work machine (<NUM>);
a first sensor (<NUM>) coupled to the implement (<NUM>, <NUM>);
a second sensor (<NUM>) coupled to the work machine (<NUM>), wherein the orientation of the implement (<NUM>, <NUM>) is identified by comparing the values of the first sensor (<NUM>) with the values of the second sensor (<NUM>);
a controller (<NUM>); and
an implement position system (<NUM>) that couples the implement (<NUM>, <NUM>) to the work machine (<NUM>),
wherein, the first sensor (<NUM>) identifies the orientation of the implement (<NUM>, <NUM>) along more than one axis (<NUM>, <NUM>, <NUM>);
wherein the controller (<NUM>) manipulates the implement position system (<NUM>) to reposition the implement (<NUM>, <NUM>) relative to the work machine (<NUM>) by comparing orientation date from the first sensor (<NUM>) to orientation data from the second sensor (<NUM>);
characterized in that the controller (<NUM>) manipulates the implement position system (<NUM>) to follow a contour of an underlying surface when the first sensor (<NUM>) identifies a prolonged movement of the implement (<NUM>, <NUM>) and the second sensor (<NUM>) does not identify a corresponding prolonged movement of the work machine (<NUM>) the implement comprising a draper head or a rotary head.