DE102020210661A1 - ATTACHMENT ARM SYSTEM WITH AUTOMATED FUNCTIONS FOR A WORK VEHICLE - Google Patents

Abstract

A work vehicle with a boom, work attachment, and linkage sensor system with automatic functions for moving the boom and work attachment. The work vehicle includes a frame, a boom actuator for the boom, a boom sensor for determining a boom position with respect to the frame, an attachment actuator and an attachment sensor for determining a work attachment position with respect to the boom. A controller receives boom position signals from the boom sensor and work attachment signals from the attachment sensor. The controller transmits a boom setting signal based on the boom position modified by calibration values of the boom sensor, and transmits an implement setting signal based on the implement position modified by calibration values of the implement sensor. The calibration values of the implement sensors are determined during a calibration process when the boom is moved from a lowest position to a highest position.

Description

FIELD OF REVELATION

The present invention relates generally to a work vehicle with a work attachment, in particular to a system and method of automated functions for the work attachment and a linkage coupled to the work attachment.

BACKGROUND

Work vehicles, such as For example, a four-wheel drive loader, tractor, or self-propelled combine harvester has a drive motor that generates power to do the job. Other work vehicles with drive motors include construction vehicles, forest vehicles, lawn maintenance vehicles and road vehicles such as. B. for snow plowing, spreading salt or vehicles with towing function.

For example, in the case of a four-wheel drive loader, the drive motor is often a diesel engine that uses diesel fuel to generate power. The diesel engine drives a transmission which has a ground-engaging traction device, such as. B. wheels or treads, moved to propel the loader over unpaved ground for use in construction in some situations. Such loaders incorporate a hydraulic machine that is driven either by the engine or by a generator that is in turn driven by the engine. The hydraulic machine is used, for example, a work attachment, such. B. a shovel or fork, raise or lower.

Many, if not all, of these work vehicles include a linkage attached to the work attachment that is moved from one position to another position by the linkage. The linkage is moved either by an operator actuating a user input device such as a rocker arm or switch, or automatically by a control system located in the work vehicle. In some of these work vehicles, the linkage is automatically moved to move the work attachment to one or more predetermined positions. Such predetermined positions are typically positions that are repeated over and over again during a work process. By automatically moving the work attachment to the predetermined position, machine operation is improved and operator fatigue is reduced. In some cases, however, due to manufacturing variances in the structure of the linkage and associated hardware, the predetermined positions may vary from machine to machine or over time in a particular machine. If there are deviations, operations become less efficient and any benefit gained from automatic positioning of the boom and / or work attachment is lost. Therefore, a positioning system is needed to move the linkage and attached work attachment from one position to the next that ensures consistent and accurate placement of the linkage and / or work attachment.

SUMMARY

In one embodiment, a method is provided for moving a work attachment and boom that are operatively connected to a work vehicle supported over a surface, the work vehicle having a work attachment sensor for determining the position of the work attachment and a boom sensor for determining the position of the boom contains. The method includes: calibrating the work attachment sensor; Calibrating the boom sensor; Raising the boom from a lowered position to a raised position; Determining a lowered position of the boom in the lowered position using the boom sensor; Determining a raised position of the boom in the raised position using the boom sensor; Determining a plurality of work attachment positions while moving the boom from the lowered position to the raised position; Determining a plurality of error values based on the determined plurality of work attachment positions; and moving the boom based on the plurality of error values during an operation.

In another embodiment, a work vehicle is provided with a frame, a boom actuator with a boom arm, the boom actuator operatively connected to the frame, and a work attachment operatively connected to the boom arm. A boom sensor is located on the boom actuator to determine a boom position of the boom arm with respect to the frame. An attachment sensor is located on the work attachment actuator to determine a work attachment position of the work attachment with respect to the boom arm. Both the boom control device and the attachment control device provide an attachment control signal. A control module is carried by the frame and is operatively connected to the boom sensor, the work attachment sensor, the boom actuator and the work attachment actuator, the control module having boom position signals from the boom sensor and Receives work attachment signals from work attachment sensor and transmits a boom setting signal to the boom actuator based on the boom position modified by a boom sensor calibration value and transmits an implement setting signal to the implement actuator based on the attachment position modified by an implement sensor calibration value.

In a further embodiment, a method for positioning a work attachment and a boom, which are operatively connected to a work vehicle, is provided, the work vehicle containing a work attachment sensor for determining a position of the work attachment and a boom sensor for determining the position of the boom. The method includes: calibrating the work attachment sensor and the boom sensor; Determining an initial work attachment position in a boom lowest position with the work attachment sensor; Determining a plurality of boom positions while moving the boom from a lowest position to a highest position using the boom sensor; Determining a plurality of work attachment positions with the work attachment sensor at each of the plurality of boom positions while moving the boom from the lowest position to the highest position and while maintaining a position of the work attachment with respect to the boom at the initial work attachment position; Comparing each of the determined plurality of work attachment positions to the initial work attachment position to arrive at a plurality of error values for the work attachment; and positioning the work attachment with the boom based on the error values for the work attachment during a work operation.

Figure list

• 1 ist eine Seitenansicht eines Arbeitsfahrzeugs mit einem Arbeitsanbaugerät in einer ersten Position;
• 2 ist eine Seitenansicht eines Arbeitsfahrzeugs mit einem Arbeitsanbaugerät in einer zweiten Position;
• 3 ist eine Seitenansicht eines Arbeitsfahrzeugs mit einem Arbeitsanbaugerät in einer dritten Position;
• 4 ist ein Blockdiagramm eines Steuersystems des Arbeitsfahrzeugs; und
• 5 ist ein Blockdiagramm eines Prozesses zur Bestimmung von Positionsfehlern in einem Gestänge zwischen Ausleger und Arbeitsanbaugerät.

The above aspects of the present invention and the manner of obtaining them will become more apparent and the invention itself better understood by referring to the following description of the embodiments of the invention in conjunction with the accompanying drawings, in which:

• 1 Figure 3 is a side view of a work vehicle with a work attachment in a first position;
• 2 Figure 3 is a side view of a work vehicle with a work attachment in a second position;
• 3rd Figure 3 is a side view of a work vehicle with a work attachment in a third position;
• 4th Fig. 3 is a block diagram of a control system of the work vehicle; and
• 5 Figure 13 is a block diagram of a process for determining position errors in a linkage between the boom and work attachment.

DETAILED DESCRIPTION

In order to promote an understanding of the principles of the novel invention, reference will now be made to the embodiments described herein and illustrated in the drawings, and these will be described in a given language. It is understood, however, that this is not intended to be a limitation on the scope of the novel invention and such changes and other modifications to the apparatus and methods depicted, as well as such other applications of the principles of the novel invention set forth herein, are contemplated in such manner would normally be considered by one skilled in the art of the novel invention.

1 Fig. 3 is a side view of a work vehicle 10 . The work vehicle 10 is a four-wheel drive (4WD) loader with: a cab 12th ; a rear body section 14th with rear wheels 16 ; a front body section 20th with front wheels 22nd , a work attachment, such as B. a shovel 24 , a linkage 26th for adjusting a position of the bucket 24 , a hydraulic cylinder 28 and a hydraulic cylinder 30th (please refer 2 and 3rd ) to the linkage 26th to drive. The shovel 24 is rotatable with a cantilever arm 31 at a fulcrum 32 coupled. A second cantilever arm, which is essentially the cantilever arm 31 is not shown, but is on an opposite side of the bucket 24 operationally with the shovel 24 connected, as it would be understood by a person skilled in the art. The cylinder 30th and the cantilever arm 31 provide a boom actuator that raises and lowers the attachment with respect to the frame of the vehicle.

An articulated joint 33 allows an angular fit of the rear body area 14th with the front body area 20th . The hydraulic cylinders 34 , 35 and 36 allow angle changes between the rear and front body sections 14th and 20th using the hydraulic power derived from conventional hydraulic pumps (not shown).

An accelerator pedal 38 and a user interface 40 are located inside the cabin, which is operated by an operator of the vehicle 10 can be used. Using the accelerator 38 the driver can regulate the speed of the vehicle. In In other embodiments, a hand lever takes over this function.

The user interface 40 includes a steering wheel 42 , a variety of operator selectable buttons configured to allow the operator to control the operation and function of the vehicle 10, as well as any accessory or attachment powered by the vehicle's driveline, including the bucket 24 . The user interface 40 in one embodiment includes a screen having a plurality of user selectable buttons for selecting from a plurality of commands or menus, each of which is selectable via a touch screen with a screen. In a further embodiment, the user interface comprises a multiplicity of mechanical pushbuttons and a touch screen. In a further embodiment, the user interface comprises a screen and exclusively mechanical pushbuttons.

As in 1 shown, is the linkage 26th in a fully lowered position with respect to the ground 27 . In this position the shovel is 24 in one to the ground 27 brought into a horizontal position so that a plane defined by a lower part of the bucket is substantially flush with the ground and substantially horizontal. For purposes of this disclosure, the position of the linkage 26th and the shovel 24 in 1 considered a fully lowered position. The linkage 26th can be lowered further than the shown position of under certain conditions 1 provided there is the surface of the soil under the shovel 24 is lower than the surface of the wheels on which the vehicle is standing.

One end of the arm 31 is operational with the shovel 24 at the fulcrum 32 connected and another end of the arm 31 is operational with a fulcrum 50 a frame construction 52 connected. As in the 2 and 3rd seen is one end of the cylinder 30th operational with the cantilever arm 31 and another end of the cylinder 30th operational with the frame 52 connected. The extension and retraction of the cylinder 30th adjusts the position of the arm 31 in terms of the frame 52 on to the shovel 24 raise and lower. By using the extension arm 31 becomes the shovel 24 from the fully lowered position of 1 to a partially raised position from 2 and to a fully raised position from 3rd emotional. The fully raised position of 3rd is controlled by one or more mechanical stops between the cantilever arm 31 , the cylinder 30th and the frame 52 certainly.

The shovel 24 is in relation to the cantilever arm 31 by actuating the cylinder 28 adjustable. One end of the cylinder 28 is with part of the vehicle 10 connected as one skilled in the art understands, and the other end of the cylinder is operative with an implement link 54 connected. The attachment link 54 is rotatable with one end of the cylinder 28 at a fulcrum 56 connected. Another end of the implement link 54 is rotatable with part of the shovel 24 connected at a pivot point. An intermediate section 60 of the link 54 is rotatable with a flange 62 coupled that is firmly attached to the arm 31 connected is. By extending and retracting the cylinder 28 becomes the shovel 24 around the fulcrum 32 turned. The cylinder 28 and the connecting link 54 provide an attachment actuator to the bucket 24 in relation to the cantilever arm 31 to move.

One sensor 64 is at or near the pivot point 50 arranged to a rotation angle of the arm 31 in terms of the frame 52 to determine. In one embodiment, the sensor is 64 surgically with the arm 31 connected by a four-bar linkage, as understood by a person skilled in the art. In another embodiment, the sensor is 64 at the fulcrum 50 arranged. When extending and retracting the cylinder 30th becomes the arm 31 in relation to the ground 27 raised and lowered. A second sensor 66 is at or near the axis of rotation of the link 54 in relation to the flange 62 arranged. When extending and retracting the cylinder 28 the shovel turns 24 around the axis of rotation 32 . An output from the sensor 64 is used to measure a height of the shovel 24 in relation to the ground, and an output of the second sensor 66 is used to indicate the slope of the shovel 24 in relation to the arm 31 to determine.

FIG. Figure 11 illustrates a block diagram of an implement control system 100 for setting a linkage system for positioning the extension arm 31 and the attachment 24 in relation to the vehicle 10 based on either manual position commands, automatic position commands, or a combination of manual and automatic position commands. The implement control system 100 includes a controller 102 such as B. an electronic control unit (ECU) connected to a Controller Area Network (CAN) bus (not shown), but in 4th is shown as double arrow lines indicating a communication link via the bus to and from the controller 102 and to the various devices and components of the vehicle 10 Show. The CAN bus is configured to transmit electrical control signals for controlling various devices connected to the bus, as well as status signals that identify the status of the connected devices.

The control 102 In various embodiments, comprises a computer, a computer system or other programmable device. In other embodiments, the controller includes 102 one or more processors 104 (e.g. microprocessors) and an associated memory 106 that can reside both inside and outside of the processor. The memory 106 In various embodiments, it comprises RAM modules (Random Access Memory) that hold the memory of the controller 102 include, as well as all other types of storage, e.g. B. cache memory, non-volatile or backup memory, programmable memory or flash memory and write-protected memory. Additionally, in other embodiments, the memory includes memory that is physically in a different location than the computing devices, and may include any cache memory in a computing device, as well as any storage capacity used as virtual memory, e.g. B. as on a mass storage device or another with the controller 102 paired computer is stored. The mass storage device can contain a cache or other data space that can contain databases. In other embodiments, the memory is located in the “cloud”, in which the memory is located at a remote location, from which the stored information can be transmitted wirelessly to the controller 102 be transmitted. When referring to the controller 102 and the memory 106 Other types of controls and other types of memories are contemplated in this disclosure.

The control 102 executes or otherwise relies on computer software applications, components, programs, objects, modules or data structures, etc. Software routines that are located in the integrated memory of the controller 102 or in another storage medium, are executed in response to the signals received from sensors as well as to signals received from other controllers or ECUs, such as e.g. An engine ECU and a transmission ECU. The control 102 , in one or more embodiments, also relies on one or more computer software applications residing in the “cloud,” where the “cloud” generally refers to a network of stored data and / or computer software programs which is accessed over the Internet. The executed software contains one or more specific applications, components, programs, objects, modules or sequences of instructions, which are typically referred to as "program code". The program code includes one or more in-memory instructions and other storage devices which execute the in-memory instructions, which are responsive to other system-generated instructions, or which have a user-operated interface.

Furthermore, while the invention is described in the context of controls, those skilled in the art will understand that the various embodiments of the invention may be distributed as a program product in a variety of forms and that regardless of the particular nature, the invention computer readable media used to actually perform the distribution is equally applicable. Examples of computer readable media include physical writable media such as volatile and non-volatile storage devices, floppy disks and other removable media, hard disk drives, optical media (e.g. CD-ROMs, DVDs, etc.), and transmission media such as electronic media. B. digital and analog communication links.

In addition, it must be understood that the process or processes described here can be implemented in various program codes and need not be limited to certain types of program code or certain organizations of such program code. In view of the typically endlessly large number of ways in which computer programs can be organized into routines, procedures, methods, modules, objects and the like, as well as the different ways in which program functionality can be distributed to different software levels that can be found within a controller or of a computer, if any are used (e.g., operating systems, libraries, APIs, applications, applets, etc.), it should be understood that the invention is not limited to any particular organization.

The vehicle 10 comprises a multiplicity of sensors, each of which determines the vehicle device status in different embodiments and sends sensor information to the controller 102 transfers that from the controller 102 run to the position of the cantilever arm 31 and the implement 24 adapt. When moving the boom 31 adjusts the control 102 the position of the cylinder (s) 30. The controller 102 adjusts the position of the cylinder (s) 30 to the attachment 24 in terms of the boom 31 to move.

The control 102 generates commands to adjust the position of the arm 31 based on sensor information received from the arm sensor 64 received and adjusts the position of the implement 24 based on sensor information from the implement sensor 66 at.

The control 102 is also operational with the operator interface 40 connected to a screen 110 , a boom control 112 , an implement controller 114 and control for returning to trench function control 116 includes. The boom control 112 is a user-controlled actuator such as B. a rocker arm, for moving the boom 31 . The implement control 114 is a user-controlled actuator for moving the attachment 24 such as B. another rocker arm. The return to the trench 116 is an actuator such as B. a push button that, if activated, is used to open the shovel 24 and the arm 31 to a return to the trench position, as in 1 shown moving. The screen 110 provides a display screen for displaying vehicle status information including real-time identification of boom height and attachment tilt. The screen 110 also includes user input buttons of one or more different types, including touchscreen buttons, contact buttons, or buttons that can be physically manipulated. In one or more embodiments, the operator user interface includes user input to identify the attachment 111 that displays a number of different types of attachments used by the vehicle 10 can be used. In some embodiments, the results of the calibration routine depend on the type of work attachment used. For example, in one example, the determined calibration values for the calibration routine of a shovel differ from the calibration values for the calibration routine of a fork. The work attachment identification user input is used to determine what type of work attachment is being used so that different calibration values are determined for different types of work attachments. In some embodiments, the kinematic model used in the calibration routine depends on the type of work attachment used. Consequently, the choice of work attachment type gives to the control module 102 the instruction which kinematic model should be used.

The memory 106 is organized as an addressable memory so that sensor information is stored as data for both the boom and the attachments in the addressable memory 108 get saved. The ones in memory 108 Stored data contain position data of the boom 31 while moving from a lowest position to a highest position. The ones in memory 108 Stored data also contain the actual position data of the implement 24 while moving between a fully extended position and a fully retracted position. The memory 106 also contains kinematic data in memory 110 for the entire kinematic chain, both the driven and the driving components, to which the boom 31 and the attachment 24 belong. The kinematic data are based on a kinematic model of the boom 31 and its actuator as well as the attachment 24 and its actuator. The kinematic data uses a mathematical formulation that takes into account the structures of the actuators and lever arms that the boom uses 31 and the attachment 24 moved as intended, as opposed to those in memory 108 stored actual position data resulting from the operation of the vehicle. The kinematic data is based on design parameters for the physical actuators and lever arms. Since physical devices are subject to manufacturing tolerances, the kinematic data do not always match the recorded data directly. The difference between the captured data and the kinematic data, also known as error data, is stored in memory 112 saved. As used here, "kinematic" refers to theoretical distances / angles of the linkage.

Automated control functions of the boom are often implemented on a material loading vehicle (such as the 4WD loader). One of these functions, commonly known as "return to dig", uses position sensors on the loader linkage to automatically return the front attachment to an operator or manufacturer specified position. If the position of the cylinder that drives the front-end equipment is not known (via an in-cylinder position detection), a system of at least two sensors, e.g. B. the boom sensor 64 and the implement sensor 66 , used to determine the location of the front end implement. A model of the linkage kinematics is used along with these two sensors to determine the position of all linkage elements. However, any inaccuracy in these two or more sensors potentially adds up the inaccuracies (also known as errors) and often results in a significant error in aligning the angular position of the front end implement. Depending on the tolerances for the various components built into the linkage systems and the sensor system, it may not be enough to use manufacturing methods to minimize the error to meet customer requirements for the automated function. So are z. B. for reaching an exact position of the boom and the work attachment extremely tight manufacturing tolerances are required, but due to the number of linkages and sensors, the tight tolerances require, are practically unattainable. In other situations, such tolerances are achievable but costly. As a result, minimizing the error in the hardware structures may not be possible or practicable.

The present disclosure includes a system having a calibration routine and process for determining existing faults in a boom / implement system. However, the routine is not limited to one type of device, such as B. a shovel, and is also used for other devices such. B. for a fork, used, but is not limited to. By determining errors, each automatic function control is compensated for by the errors determined, whereby the boom and the attachment can be positioned more precisely. In a loader linkage, for example, the angular position error of the front end equipment is, in various embodiments, a function of boom height. Different boom positions produce different error stacks, with the errors in the two or more sensors added together that are used to calculate the front end attachment position . To overcome the faults present in the loader linkage, in one or more embodiments, the present system and method provides a fault calibration routine to compute a fault table based on boom position.

5 Figure 11 illustrates a block diagram of a method 200 to determine angular position errors in a linkage for a boom / work attachment and to use the detected errors to position the boom and / or work attachment over the entire range of motion in either an automatic function or manual control. The block diagram 200 discloses a process that calculates an error in the position of the front end equipment (work attachment), the calculation being based on or a function of boom height. The work attachment position is calibrated following a position sensor calibration routine. By first calibrating the position sensors, the determination of a fault in the front end equipment is made more precise. During a typical position sensor calibration routine, the boom is actuated between its fully lowered position and its fully raised position. The data recorded at both ends of the travel path are interpolated between the two end positions to determine a real-time position of the boom as it moves from one end of the range of motion to the other end of the range of motion. A similar calibration routine is performed for the front attachment. The positions of the boom and the front part attachment can be determined in real time on the basis of these determined calibration points.

The process of 5 starts at a start position 202 after starting the work vehicle 10 begins by the operator. As soon as the vehicle is running, the operator raises the boom 31 in a highest position so that the boom 31 at block 204 is fully raised. (Please refer 3rd ) In one embodiment, the screen shows 110 the user interface 40 a process start button that is pressed by the operator to start the routine. When pressed, the screen displays a series of steps that the operator must take. In a first step 204 the screen instructs the operator, the boom 31 with one of the controls, such as B. the rocker arm to lift completely. Once the boom is fully raised, the operator makes a selection on the user interface to see if the boom is in the fully raised position. In another embodiment, the controller determines 102 the fully raised position of the boom. As soon as the fully raised position has been determined, the control saves 102 this position as a fully raised calibration point in memory 106 including one from the sensor 64 generated sensor value. Once saved, the screen instructs the operator to use the boom 31 using one of the controls at Block 206 lower completely. Once the boom is fully lowered, the operator makes a selection on the user interface to see if the boom is in the fully lowered position. (Please refer 1 ) In a further embodiment, the controller determines 102 the position of the boom in its lowest position. In further embodiments, the order of raising and then lowering is reversed.

As soon as the fully lowered position has been determined, the control saves 102 this position as a fully lowered calibration point, including one from the sensor 64 generated sensor value, in memory 106 . To fully lower the boom, the operator will tip the work attachment under most conditions 24 towards the cabin 12th so that the boom can be fully lowered.

As soon as the highest and lowest position values of the boom have been determined and saved, the screen instructs the operator to use the work attachment 24 using one of the controls, such as B. the rocker arm to tilt completely in a first direction. In most cases the operator will raise the boom 31 enough off the ground to allow full rotation of the work attachment 24 to allow in both directions. (Please refer 2 ) As soon as the work attachment is at Block 208 has been tilted completely in the first direction, the operator determines the first directional position using the user interface and the value of the sensor 64 is stored in memory as the first calibration point for a first fully flipped value. In another embodiment, the controller determines 102 the position of the work attachment and saves this value of the first direction position as the calibration point at block 210 In the storage room 106 . Once saved, the screen instructs the operator to use the work attachment 24 using the controls at Block 210 to tilt completely in a second direction. After the attachment has been fully tilted (or rotated) in the second direction, the operator determines the position in the second direction using the user interface and the value of the sensor 64 is determined using the value of the sensor 64 stored in memory as a second calibration point. In another embodiment, the controller determines 102 the position of the work attachment and saves this second direction position as a calibration point at block 210 In the storage room 106 . In one or more further embodiments, the steps 204 , 206 , 208 and 210 either partially or completely by the controller 102 automated. In the embodiment of 5 the screen provides a calibration input device such as B. a button, ready, the control after selection by the operator 102 instructs to move the boom from its lowest position to its highest position and to move the work attachment from its fully tilted first position to its fully tilted second position.

After step 210 become the boom sensor 64 and the implement sensor 66 calibrated for the travel end positions of the boom and the travel end positions of the implement. These values are in memory 106 saved. In one or more embodiments, the sensor generate 64 and the sensor 66 an output signal with a voltage representative of the position of the boom 31 and the work attachment 24 is. For example, in one embodiment, each of the sensors generates 64 and 66 a signal with a voltage range of 0.5 to 4.5 volts. The value at 0.5 volts corresponds to one extreme and the value at 4.5 volts to the opposite extreme. A point in the middle between the two voltages, around 2.5 volts, indicates that the boom is in the middle 31 and the work attachment 24 down. Other types of sensors are also contemplated.

After the sensor calibration for the sensors 64 and 66 an error (resulting from the hardware tolerance stack) is detected by the boom 31 is moved from the fully lowered position to the fully raised position, with the front attachment part remaining in a stationary position. The attachment angle of the front part attachment (calculated as a function of the system by one or more sensors for measuring the boom positions) is kept constant over the entire travel path of the boom. Consequently, any deviation of the work attachment from the starting position is considered to be traceable to an error that results from the detection system and / or the hardware. While the boom is being raised, a memory table is created in order to store one or more deviations from the starting position of the work attachment with the detected position of the work attachment when the boom is raised. This deviation is determined as an error and stored as a function of the boom height. The stored error is used by an automatic function control routine to "compensate" for the front attachment setpoint based on the current boom position.

The operator will after calibrating the sensors 64 and 66 through one on the screen 110 prompt will be instructed by the system to determine the errors. The prompt instructs the operator to use the boom 31 fully lower and the work attachment 24 at the level of the floor 27 at block 212 to turn off. This point is considered the "starting position". After lowering and correctly positioning the work attachment, the operator confirms an entry on the screen 110 that the specified position of the boom 31 and the work attachment 24 was achieved. In one embodiment, the screen includes 110 a user input selected by the operator to confirm the correct position. After confirmation, the home position for the work attachment will be determined by the controller based on that of the sensors 64 and 66 input received is determined based on or depending on the after the blocks 204 , 206 , 208 and 210 calculated calibration points. The calculated starting position is determined and stored in memory 106 at block 214 saved. The home position of the work attachment, in one or more embodiments, corresponds to the angle of the attachment passed by the cylinder 28 is determined. The stroke of the cylinder rod 28 is set to a certain extent so that the cylinder rod protrudes from the cylinder body in order to position the attachment in the starting position. In one example, the implement angle in the home position is 52 degrees.

As soon as the stroke of the cylinder has been determined and saved, the operator will be informed by the Screen instructed the boom 31 from its lowered position at Block 212 to a fully raised position at block 216 to raise. When lifting the boom 31 (while the cylinder stroke position of the cylinder 28 is kept constant), the values of the work attachment sensor 66 and the values of the cantilever arm sensor 64 from the controller 102 receive. When lifting (or in another embodiment when lowering the boom from the highest position to the lowest position) the control stores 102 those from the implement sensor 66 and from the boom sensor 64 received values at predetermined locations on the cantilever arm as it moves from its lowest position to its highest position. At each of these predetermined positions, the recorded values of the implement angle and the boom angle that are generated by the sensors 64 and 66 to the controller 102 are provided, determined and used to calculate an implement cylinder lift value that is an angle of the work attachment with respect to the boom arm 31 represents.

When the boom is moved from the lowest position to the highest position, the angle of the attachment changes due to the kinematics of the linkage. The value that depends on the sensors 64 and 66 is determined in the home position corresponds to the implement cylinder lift value or position that does not change when the boom is raised or lowered. This cylinder position value, which is also the starting angle of the work attachment, is used as a baseline to determine an error value in the movement of the boom.

In one embodiment, the attachment and boom angles determined by the sensors are used together with kinematic data that are provided by a kinematic model of the boom and the attachment. These values are in memory 110 saved to the error between the stroke value of the home position of the implement cylinder 28 (ie, 52 degree implement angle in this example) and a calculated value of cylinder position using the boom and implement sensor readings. Due to deviations from machine to machine due to manufacturing tolerances, the calculated value of the cylinder position can and will vary compared to the original cylinder position. This error is calculated at each given position and stored as a calibration value in memory 112 saved. In one embodiment, the predetermined positions are increased every 10% increment of movement of the boom 31 from its lowest position to its highest position on block 218 determined.

When the boom is raised, the control receives 102 a boom position signal from the boom sensor 64 . The control 102 determined by block 220 whether the boom at block 220 has been increased by a 10% step. If it has not been increased by 10%, the control monitors 102 continue to raise the boom at block 218 . When it is increased by an increment of 10%, the controller logs and saves a cylinder position error related to the position of the work attachment 24 at block 222 is representative. This error value is determined on the basis of the previously stored starting position of the cylinder position, which is subtracted from the currently determined position of the cylinder. At block 224 determines the controls 102 whether the boom 31 has been raised completely. Otherwise, the monitoring of the boom position at Block 218 continued. When the boom is fully raised the calibration is at block 226 completed.

While the cylinder position error for every 10% movement of the boom height in 5 is stored, in other embodiments the cylinder position error is stored at different percentages of boom height. For example, in one embodiment, the cylinder position error is stored for every 5% movement in boom height using the determined position of the attachment with respect to the boom. Other percentages are contemplated.

In one or more embodiments, the cylinder position error, which correlates with an error in the front-end attachment, correlates with the cylinder position at the starting position. For example, in one example, the home position of a bucket is 52 degrees and the home position of a fork is 60 degrees, each of these positions having a different cylinder stroke value. Thus, in one embodiment, the calibration routine generates a two-dimensional error table that is dependent on both the boom height and the cylinder stroke value. While such a calibration routine potentially allows for a more accurate determination of errors, such a calibration routine requires additional time to perform a full calibration. However, using a single position (the home position in this example) of the cylinder stroke value, the calibration routine provides an error determination sufficient to accurately locate the work attachment. In other embodiments, the calibration routine is controlled automatically to ensure that the cylinder stroke value does not change (by overriding the operator's ability to move it) and to limit the speed of the boom (to ensure that the calibration points are timely recorded).

Determined once and in memory 112 Stored for each incremental boom height, these error values are used to position the work attachment on an operator directed return to digging operation. The "Return to Dig" user input 116 or the "Return to Dig" actuator located at the user interface 40 is operated by the operator if necessary. During a return to dig operation, the controller generates 102 a boom position command or a boom set signal to move the boom 31 and generates a work attachment command or boom set signal for movement of the work attachment 24 using the cylinder 28 . In one or more embodiments, these position commands are based on the kinematic model of the positioning system, which is generally identical for all work vehicles of a particular type. Each vehicle may and often does differ from another vehicle of the same type due to differences in the manufacturing tolerances of the parts. Once the calibration routine for a particular vehicle is complete, the controller will modify the return to ditch command for that vehicle based on the kinematic model based on the determined calibration values 112 . In this way, each vehicle is individually modified or adapted to accommodate the particular structures of the parts used in the assemblies of the booms and work attachments.

The calibration routine is not limited to returning to digging operations, rather it is applicable to other functions of the work vehicle where the calibrated errors are used to override ordinary operator commands. For example, in one embodiment, the calibrated errors are used for an automatic leveling function that automatically controls the leveling position of the work attachment as the boom moves up and down. In this embodiment for a shovel, the shovel is pivoted in and out on the boom in order to keep the shovel on the ground relative to the vehicle. The error compensation is used to compensate for the automatic leveling function, which improves the precision of the movement. Other functions are contemplated.

While exemplary embodiments incorporating the principles of the present invention have been disclosed above, the present invention is not limited to the disclosed embodiments. Rather, this application is intended to cover any variations, uses, or adaptations of the invention using its general principles. While z. B. the hybrid drive train control and the engine control device are shown as separate devices, the hybrid drive train control and the energy control device are designed as a single device in other embodiments. Likewise, in other embodiments, all of a vehicle's control functions, including speed control, are performed as a single device. Furthermore, this application is intended to cover such departures from the present disclosure that correspond to known or common practice in the art to which this invention pertains.

Claims (20)

A method of moving a work attachment and boom operatively connected to a work vehicle supported over a surface, the work vehicle including a work attachment sensor for determining a position of the work attachment and a boom sensor for determining a position of the boom, the method including includes: Calibrating the work implement sensor; Calibrating the boom sensor; Raising the boom from a lowered position to a raised position; Determining a lowered position of the boom in the lowered position using the boom sensor; Determining a raised position of the boom in the raised position using the boom sensor; Determining a plurality of work attachment positions while moving the boom from the lowered position to the raised position; Determining a plurality of error values based on the determined plurality of work attachment positions; and Moving the boom based on the plurality of error values during an operation. Procedure according to Claim 1 wherein the step of raising the boom comprises raising the boom from a fully lowered position to a fully raised position. Procedure according to Claim 2 wherein the step of raising the boom further comprises raising the boom from the lowered position to the fully raised position while the work attachment remains stationary with respect to the boom. Procedure according to Claim 3 wherein calibrating the work attachment sensor includes: moving the work attachment to a fully tilted position in a first direction; Determine the position of the work attachment in the fully tilted position in the first direction. Procedure according to Claim 4 wherein calibrating the work attachment sensor includes: moving the work attachment to a fully tilted position in a second direction; and determining the position of the work attachment in the fully tilted position in the second direction. Procedure according to Claim 5 wherein the step of raising the boom includes lowering the boom fully to the fully lowered position and setting the work implement to a level ground position. Procedure according to Claim 6 wherein determining the plurality of boom positions includes determining each of the plurality of boom positions at regularly spaced boom positions between the fully lowered position and the fully raised position. Procedure according to Claim 7 wherein the regularly spaced boom positions are spaced approximately every ten percent of a distance between the fully lowered position and the fully raised position. Method according to one of the Claims 1 to 8th wherein moving the boom based on the plurality of error values includes moving the boom in response to a return to the digging operation. Procedure according to Claim 9 further comprising displaying a user accessible return to dig actuator on a user interface. Work vehicle, comprising: a frame, a boom actuator including a boom arm, the boom actuator being operatively connected to the frame, a work attachment operatively connected to the boom arm; a boom sensor disposed on the boom actuator to determine a boom position of the boom arm with respect to the frame; an attachment sensor disposed on the work attachment actuator to determine a work attachment position of the work attachment with respect to the boom arm; a boom controller to provide a boom control signal; an implement controller to provide an implement control signal; a control module supported by the frame and operatively connected to the boom sensor, work attachment sensor, boom actuator, work attachment actuator, boom controller, and attachment controller, the control module receiving and sending to the boom position signals from the boom sensor based on a boom position signal from the boom sensor on the boom position modified by a boom sensor calibration value and transmits to the implement actuator an implement setting signal based on the implement position modified by an implement sensor calibration value. Work vehicle after Claim 11 further comprising a user interface having a digging return actuator, wherein actuation of the digging return actuator adjusts a position of the work attachment with respect to the boom arm based on the boom sensor calibration value and the implement sensor calibration value. Work vehicle after Claim 12 wherein the control module includes a processor and memory, the memory having a plurality of program instructions and a memory table for storing error values based on a model of the boom actuator kinematics and a model of the implement actuator kinematics generated in response to execution by the processor of the control module causes the error values to be determined on the basis of the following: determining a fixed position of the work attachment in relation to the boom arm, the fixed position of the work attachment being determined by a position of the attachment actuator, determining a position of the boom arm in relation to the frame using the boom sensor at a A plurality of positions between a fully lowered boom position and a fully raised boom position while maintaining the position of the work attachment with respect to the frame, comparing the determined plurality of positions with the model of the boom actuator kinematics to arrive at the multitude of error values. Work vehicle after Claim 13 wherein the user interface includes the boom control, the implement control, and a user input key operatively connected to the control module, the user input key, when selected by the user, detecting and storing in memory a lowest boom position and a highest boom position. Work attachment according to Claim 14 wherein the processor causes the control module to display a user prompt to instruct the operator to move the work attachment to the fixed position if the boom is fully lowered. Work attachment according to Claim 15 wherein the trench return actuator adjusts the position of the work attachment using the plurality of error values. Work attachment according to Claim 16 , wherein the user interface contains a user input for determining the type of work attachment attached to the work vehicle. A method of positioning a work attachment and a boom operatively connected to a work vehicle, the work vehicle including a work attachment sensor for determining a position of the work device and a boom sensor for determining a position of the boom, the method comprising: Calibrating the work attachment sensor and the boom sensor; Determining an initial position of the work attachment at a boom lowest position using the work attachment sensor; Detecting a plurality of boom positions while moving the boom with the boom sensor from a lowest position to a highest position; Determining a plurality of work attachment positions using the work attachment sensor at each of the plurality of boom positions while moving the boom from the lowest position to the highest position and while maintaining a position of the work attachment with respect to the boom in the initial position of the work attachment; Comparing each of the determined plurality of work attachment positions using the initial work attachment position to achieve a plurality of work attachment error values; and Positioning the work attachment using the boom based on the error values of the work attachment during a job. Procedure according to Claim 18 wherein calibrating the work attachment sensor and the boom sensor comprises: i) determining a first boom position at the lowest position using the boom sensor; ii) determining a second boom position at the highest position using the boom sensor; iii) determining a first work attachment position at a first extreme position; and iv) determining a second work attachment position at a second extreme position opposite the first extreme position. Procedure according to Claim 19 wherein positioning the work attachment includes positioning the work attachment in response to a return to the digging operation.

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