Patent Grant
10570582
The present disclosure relates generally to a material-handling machine and, more particularly, to a system and a method for operating a material-handling machine.
Material-handling machines, such as excavators, wheel loaders, forklifts, and the like, may be used to transport materials about a worksite. An operator may provide control inputs that cause an implement of the machine to perform a sequence of operations that complete a work cycle. The sequence of operations may include loading the implement with material, lifting the implement and material, transporting the material across the worksite via the implement, and unloading or dumping the material from the implement.
US Patent Application Publication Number 2015/0077557 (hereinafter “the '557 publication”), purports to describe a system which senses a target on a towed implement and automatically controls the steering and movement of a vehicle to align the vehicle with the towed implement which is to be coupled to the vehicle, such as a wagon or trailer. According to the '557 publication, a towing vehicle, such as an agricultural tractor, has a conventional hitch and/or a drawbar for coupling to an implement, and a pair of cameras that are mounted on a rear upper portion of the towing vehicle. A target is mounted on the towed implement so as to be viewable from the direction of the vehicle.
The vehicle of the '557 publication further includes and electronic control unit (ECU) that processes the images from the cameras and generates tractor movement commands that cause the vehicle to move to a position that permits the implement to be coupled to the tractor. However, the vehicle and implement alignment system of the '557 publication may not benefit other cycles performed by other machines, such as cycles of material-handling machines that benefit from movement of the machine relative to a worksite, coordinated with movement of a machine implement relative to the machine. Accordingly, there exists a need for improved material-handling machine operating systems and methods to address the aforementioned challenges and/or other problems in the art.
It will be appreciated that this background description has been created to aid the reader, and is not a concession that any of the indicated problems or challenges were themselves previously known in the art.
According to an aspect of the disclosure, a machine includes a power generation system, a propulsion system operatively coupled to the power generation system for transmission of power therebetween and configured to propel the machine over a work surface, and a work implement operatively coupled to the power generation system for transmission of power therebetween and coupled to a body of the machine via a linkage that includes at least one actuator; and a system for controlling the machine comprises a perception system configured to generate a signal that is indicative of a position of the machine relative to a material receptacle; and a controller operatively coupled to the perception system, the propulsion system, the power generation system, and the at least one actuator. The controller is configured to receive the signal from the perception system, determine a location of the work implement relative to the material receptacle based at least in part on the signal from the perception system, and actuate at least one of the propulsion system, the power generation system, and the at least one actuator based on the determined location of the work implement relative to the material receptacle to transfer a material from the work implement to the material receptacle while avoiding contact between the work implement and the material receptacle.
According to another aspect of the disclosure, a machine includes a power generation system, a propulsion system operatively coupled to the power generation system for transfer of power therebetween and configured to propel the machine over a work surface, a work implement operatively coupled to the power generation system for transfer of power therebetween and coupled to a body of the machine via a linkage that includes at least one actuator, and a perception system configured to generate a signal that is indicative of a position of the machine relative to a material receptacle; and a method for controlling the machine comprises receiving within a controller the signal from the perception system; determining, via the controller, a location of the work implement relative to the material receptacle based at least in part on the signal from the perception system, and actuating, via the controller, at least one of the propulsion system, the power generation system, and the at least one actuator based on the determined location of the work implement relative to the material receptacle to transfer a material from the work implement to the material receptacle while avoiding contact between the work implement and the material receptacle.
According to another aspect of the disclosure, a machine comprises a power generation system, a propulsion system operatively coupled to the power generation system for transfer of power therebetween and configured to propel the machine over a work surface; a work implement operatively coupled to the power generation system for transfer of power therebetween and coupled to a body of the machine via a linkage that includes at least one actuator; a perception system configured to generate a signal that is indicative of a position of the machine relative to a material receptacle; and a controller operatively coupled to the perception system, the propulsion system, and the at least one actuator. The controller is configured to receive the signal from the perception system, determine a location of the work implement relative to the material receptacle based at least in part on the signal from the perception system, and actuate at least one of the propulsion system, the power generation system and the at least one actuator based on the determined location of the work implement relative to the material receptacle to transfer a material from the work implement to the material receptacle while avoiding contact between the work implement and the material receptacle.
Aspects of the disclosure will now be described in detail with reference to the drawings, wherein like reference numbers refer to like elements throughout, unless specified otherwise.
The machine 102 illustrated in
The at least one transmission mechanism 124 is operatively coupled to the power source 122 and configured to convert shaft power from the power source 122 into another form of power, such as hydraulic power, pneumatic power, or electric power; modify an attribute of shaft power from the power source 122, such as rotational speed or torque of the shaft power; or combinations thereof. The at least one transmission mechanism 124 may include a gear train, a torque converter, a drive shaft, a clutch, a belt-and-pulley system, a chain-and-sprocket system, a hydraulic pump, a pneumatic compressor, an electric generator, combinations thereof, or any other transmission mechanism known in the art.
The propulsion system 116 includes at least one propulsion device 126 and at least one braking device 128. The at least one propulsion device 126 is operatively coupled to the power source 122 via the at least one transmission mechanism 124 for transmission of shaft power therebetween, and configured to effect movement of the body 112 of the machine 102 relative to the work surface 104. For example, the at least one propulsion device 126 may be operatively coupled to the power source 122 via a gear box for transmission of shaft power therebetween, or the at least one propulsion device 126 may be operatively coupled to an electric motor that receives electric power from the power source 122. The at least one propulsion device 126 may include a wheel, a track belt, combinations thereof, or any other propulsion device known in the art.
The at least one braking device 128 is configured to absorb kinetic energy from the at least one propulsion device 126, thereby retarding motion of the body 112 of the machine 102 over the work surface 104. The at least one braking device 128 may store or dissipate the kinetic energy absorbed from the at least one propulsion device 126. For example, the at least one braking device 128 may absorb and dissipate kinetic energy from the at least one propulsion device 126 as heat generated by friction between two surfaces; absorb kinetic energy from the at least one propulsion device 126, convert the kinetic energy to electrical energy through an electric generator, and store the electrical energy in a battery; or combinations thereof.
The implement system 118 includes a work implement 130 that is coupled to the body 112 via a linkage 132, and at least one actuator 134 coupled to the linkage 132 that is configured to effect relative motion between the work implement 130 and the body 112. The work implement may be a loader bucket, an excavator bucket, a forklift fork, a log grappler, or any other work implement known in the art of material handling. The work implement 130 illustrated in
The linkage 132 illustrated in
According to an aspect of the disclosure, the lift actuator 138, the tilt actuator 142, or both, may be linear hydraulic cylinders that are coupled to the power source 122 via one or more hydraulic pumps in the at least one transmission mechanism 124. However, it will be appreciated that the lift actuator 138 and the tilt actuator 142 may comprise other types of actuators know in the art to suit a particular application.
According to an aspect of the disclosure, the vertical direction 150 is substantially perpendicular to the work surface 104, and the forward direction 152 is perpendicular to the vertical direction 150 along a direction of forward travel of the machine 102. “Substantially perpendicular” may include deviations of +/−3 degrees from perpendicular, for example. It will be appreciated that the vertical direction 150, the forward direction 152, or both, may alternatively be defined with respect to a gravity direction 154. It will be further appreciated that the work surface 104 may include portions with different inclines or slopes with respect to the gravity direction 154, and that the vertical direction 150 may be determined relative to a portion of the work surface that is occupied by the machine 102, a portion of the work surface that is occupied by the material receptacle 106, combinations thereof, or another portion of the work surface.
The perception system 120 may include at least one perception device 158, such as a monocular camera, a stereo camera, a Light Detection and Ranging (LiDAR) system, a Global Positioning System (GPS) unit, combinations thereof, or any other perception device known in the art. It will be appreciated that the perception system 120 may be mounted on the machine 102, or alternatively be mounted remotely from the machine 102 but in data communication with the machine 102. According to an aspect of the disclosure, the at least one perception device 158 does not include a GPS unit.
The perception system 120 is configured to determine the locations of one or more points on the machine 102 relative to points on the material receptacle 106, angular alignment of a plane defined by the machine 102 relative to a plane defined by the material receptacle 106, or combinations thereof. For example, the perception system 120 may be configured to identify a top edge 160 of the material receptacle 106, and determine a vertical distance 162 along the vertical direction 150 and a horizontal distance 164 along the forward direction 152 from the top edge 160 of the material receptacle 106 to a leading edge 166 of the work implement 130.
Alternatively or additionally, as shown in the plan view of a worksite 100 illustrated in
Furthermore, the perception system 120 may be configured to identify a proximate wall 180 of the material receptacle 106, and determine an angle 182 defined between a plane of the proximate wall 180 and a reference plane 184 of the machine 102 defined by the forward direction 152 and the vertical direction 150. Alternatively or additionally, the perception system 120 may be configured to identify a reference plane 186 of the material receptacle 106 defined by a longitudinal axis 188 of the material receptacle 106 and the vertical direction 150, and determine an angle 190 defined by the reference plane 186 of the material receptacle 106 and the reference plane 184 of the machine 102. Moreover, it will be appreciated that the perception system 120 may be configured to determine the location of the machine 102 relative to the material receptacle 106 according to other spatial metrics.
Returning to
The at least one operator input device 194 may include a joystick, a button, a touchscreen, a keyboard, a mouse, a dial, a slider, a microphone, a valve, a lever, combinations thereof, or any other user input device known in the art. It will be appreciated that the at least one operator input device 194 may receive control inputs from onboard the machine 102, off-board the machine 102 via wired or wireless telemetry, or both. Further, it will be appreciated that the at least one operator input device 194 may generate an actuating signal to control operation of an aspect of any one of the power source 122, the at least one transmission mechanism 124, the at least one braking device 128, the perception system 120, the propulsion system 116, the work implement system 118, or combinations thereof.
The machine 102 further includes a controller 196 that is operatively coupled to the at least one operator input device 194, the power generation system 114, the propulsion system 116, the implement system 118, the perception system 120, combinations thereof, or any other system of the machine 102 that could benefit from receipt of control signals. Thus, the controller 196 may be any purpose-built processor for effecting control of any operational aspect of the machine 102.
It will be appreciated that the controller 196 may be embodied in a single housing, or a plurality of housings distributed onboard the machine 102, off-board the machine 102, or both. Further, the controller 196 may include power electronics, preprogrammed logic circuits, data processing circuits, volatile memory, non-volatile memory, software, firmware, input/output processing circuits, combinations thereof, or any other controller structures known in the art.
The communication from the perception system 120 to the controller 196 may include encoded signals that are indicative of a position of the machine 102 relative to the material receptacle 106, a position of the machine 102 relative to the work surface 104, or both. Furthermore, the controller 196 may send actuating signals to the perception system 120 to trigger a scan or data collection, or otherwise tailor operation of the perception system 120.
The material receptacle 106 may optionally have a GPS unit 206 associated therewith, that is operatively coupled to the controller 196 for transmitting a signal that is indicative of a location of the material receptacle 106 relative to the work surface 104. Accordingly, the controller 196 may determine a location of the machine 102 relative to the material receptacle 106 based on a difference between a location of the machine 102 relative to the work surface 104 and a location of the material receptacle 106 relative to the work surface 104. Such an alternate determination of the location of the machine 102 relative to the material receptacle 106 may be useful, for example, when the material receptacle 106 is outside of a zone of detection 208 of other perception devices 158, such as cameras or LiDAR.
The communication from the power source 122 to the controller 196 may include signals indicative of a rotational speed of the power source 122, or any other operational state of the power source 122 known in the art. The communication from the controller 196 to the power source 122 may include actuating signals for setting a target rotational speed, effecting a target fuel injection schedule, combinations thereof, or any other engine actuation signal known in the art.
The communication from the at least one transmission mechanism 124 to the controller 196 may include signals indicative of output shaft speeds, hydraulic supply pressures, electric supply voltages, or combinations thereof. Furthermore, the controller 196 may send actuating signals to the at least one transmission mechanism 124 to engage or disengage a clutch, change a gear ratio, vary a hydraulic pump displacement, combinations thereof, or any other transmission actuation signal known in the art. The controller 196 may be configured to determine a land speed of the body 112 of the machine 102 relative to the work surface 104 based on signals indicative of output shaft speeds from the at least one transmission mechanism 124 and information regarding gear ratios, tire diameters, and the like, for the machine 102.
The communication from the work implement system 118 to the controller 196 may include signals indicative of hydraulic pressure, hydraulic flow rate, linear hydraulic cylinder velocity, work implement 130 velocity state, work implement 130 system positional state, or combinations thereof, associated with the lift actuator 138, the tilt actuator 142, or both. In turn, the controller 196 may be configured to determine a position, orientation, velocity, or combinations thereof, associated with points on the work implement 130, the lift arm 136, the tilt linkage 140, or combinations thereof, based on sensor signals from the work implement system 118 and information regarding the geometry of the work implement system 118. Furthermore, the controller 196 may send actuating signals to the work implement system 118 to effect a desired direction of motion, velocity of motion, force, or combination thereof, associated with the lift actuator 138, the tilt actuator 142, or both.
The controller 196 may send actuating signals to the at least one braking device 128 to modulate the retarding force applied by the at least one braking device 128 to elements of the propulsion system 116, including disengagement of the at least one braking device 128 from applying any substantial retarding force to an element of the propulsion system 116. According to an aspect of the disclosure, the at least one braking device 128 is a service brake of the machine 102.
Control signals output from the controller 196 to various actuators of the machine 102 may be based on control command signals generated by the at least one operator input device 194; logic encoded in a memory 200 and executed in a processor 202 of the controller 196, or combinations thereof. Thus, operation of the machine 102 may be effected by completely manual control inputs from the at least one operator input device 194; completely automatic control inputs from the processor 202; manual control inputs from the at least one operator input device 194 that are modified by logical instructions executed within the processor 202; or combinations thereof.
The controller 196 may include a cycle counter unit 204, which may detect loading and unloading cycles of the implement 130, and index a counter in response to detection of completing a loading and unloading cycle of the implement 130. The loading and unloading cycles may be detected, at least in part, by pattern recognition from operating data obtained from the work implement system 118, the at least one transmission mechanism 124, the propulsion system 116, or combinations thereof.
According to an aspect of the disclosure, the controller 196 may estimate the amount of material 108 delivered by the machine 102 according to a number of loading and unloading cycles. According to another aspect of the disclosure, the controller 196 may estimate the remaining capacity in a material receptacle 106 to receive more material 108 based on a number of loading and unloading cycles performed with that material receptacle 106 and the overall capacity (weight or volume, for example) of the material receptacle 106.
The present disclosure is generally applicable to material-handling machines and operation of material-handling machines for loading a material into a material receptacle.
Operations for unloading a material 108 from an implement 130 of a material-handling machine 102 pose challenges with respect to operator skill, fatigue, and visibility of the unloading zone. Indeed, unloading operations may require the operator to maintain precise control of the implement in close proximity to other worksite structures, such as a material receptacle 106, throughout repetitive unloading cycles.
Less experienced operators may cause unintended contact between the material-handling machine 102 and the material receptacle 106, which may cause damage to the material-handling machine 102 or the material receptacle 106, and which may result in less than optimum productivity. Furthermore, the repetitive nature of the loading and unloading cycles may cause operator fatigue, which may also cause less than optimum productivity.
Situations where the operator has limited visibility of the unloading zone adjacent the material receptacle 106 may also be prone to unintended contact between the material-handling machine 102 and the material receptacle 106, reduced productivity, or both. Although assistance from a second operator, located outside the operator cab 192, may promote accuracy of unloading operations by conveying instructions to an operator within the operator cab 192, employing a second operator to aid the unloading operations may unduly burden the cost of the operation.
Systems and methods according to aspects of the present disclosure alleviate the aforementioned challenges with unloading operations by determining the location of the implement 130 of the material-handling machine 102 relative to a material receptacle 106, and then by having a controller 196 fully automate the unloading operation, or intervene to override or modify manual control inputs from an operator during the unloading operation.
Next, in step 406, the machine 102 is located in a staging area in preparation for unloading material 108 from its implement 130 into a material receptacle 106. In the case of a material receptacle 106 that is stationary with respect to the work surface 104, the staging area may be an area that locates the implement 130 relative to the material receptacle 106 within less than about an overall length of the machine 102 along the forward direction 152. Alternatively, the staging area may be an area that locates the material receptacle 106 within the zone of detection 208 of the perception system 120.
In the case of a mobile material receptacle 106, such as the bed of a dump truck 110, that has not yet reached its loading location, the staging area may be an area that locates the implement 130 within less than about an overall length of the machine 102, along the forward direction 152, within an anticipated loading location for the material receptacle 106. The implement 130 may be raised from a carrying height to an approximate unloading height by actuating the lift actuator 138, while the operator of the machine 102 waits for the material receptacle 106 to travel to the loading location.
In step 408 the material receptacle 106 is located within the zone of detection 208 of the perception system 120, and the controller 196 may proceed to locate features of the material receptacle 106 relative to the implement 130 or other portion of the machine 102 based on input from the perception system 120.
In step 410, relative motion between the machine 102 and the material receptacle is effected to align the machine 102 with the material receptacle 106 in a way that facilitates transfer of the material 108 from the implement 130 to the material receptacle. The relative motion between the machine 102 and the material receptacle 106 may be effected by moving the machine 102 relative to the work surface 104, moving the receptacle 106 relative to the work surface 104, or combinations thereof.
According to an aspect of the disclosure, the machine 102 may be a wheel loader, and the relative motion between the wheel loader and the material receptacle 106 may be effected by operating the propulsion system 116 of the wheel loader, the implement system 118 of the wheel loader, or both, to move the implement 130 relative to the work surface 104. According to another aspect of the disclosure, the machine 102 may be an excavator having a body 112 that is fixed stationary with respect to the work surface, perhaps fixed by outriggers engaged with the work surface 104, and the relative motion between the excavator and the material receptacle 106 may be effected by operating the implement system 118 of the excavator (perhaps including boom, stick, and swing actuators) to move the implement 130 relative to the work surface 104.
Next, in step 412, the material receptacle 106 is loaded with material 108 by transferring the material 108 from the implement 130 of the machine 102 to the material receptacle 106.
Optionally, in step 414, the operator or the controller 196 determines whether the material receptacle 106 is full. If the material receptacle 106 is full, then the method 400 may proceed to the end at step 416. Else, if the material receptacle 106 is not full, then the method 400 may return to step 412 for additional material 108 loading. The controller 196 may determine whether the material receptacle 106 is full by counting a number material loading and unloading cycles performed with that particular receptacle 106 via the cycle counter unit 204, and by comparing the number of material loading and unloading cycles to a capacity of the material receptacle 106.
From the start 502, the method 500 proceeds to step 504, where the controller 196 determines a distance between a reference point of the material receptacle 106 and a reference point of the machine 102 based on input from the perception system 120. Non-limiting examples of the reference point on the material receptacle 106 include a point on the left edge 168 of the material receptacle 106 or a point on the right edge 174 of the material receptacle 106. Non-limiting examples of the reference point of the machine 102 include the left edge 172 of the implement 130 and the right edge 178 of the implement 130 (see
Next, in step 506, the controller 196 determines whether the distance between the reference point on the material receptacle 106 and the machine 102 is less than a threshold distance. The threshold distance may be selected to ensure sufficient alignment along the transverse direction 156 to avoid spilling material 108 from the implement 130 to outside the material receptacle 106, thereby diminishing productivity of the material transfer. Alternatively or additionally, the reference distance may be selected to promote a desired material 108 distribution within the material receptacle 106.
If the distance is less than the threshold distance in step 506, the method 500 may proceed to step 508, where the controller 196 determines an angle between a reference plane of the material receptacle 106 and a reference plane of the machine 102. Referring to
Next, in step 510, the controller 196 may determine whether the angle determined in step 508 is within a target range. The angle target range may be defined based on geometries of the machine 102, the material receptacle 106, or both, to ensure that the implement 130 may be able to unload material 108 into the material receptacle 106 without having unintended contact between the machine 102 and the material receptacle 106. For the reference planes 184 and 186 illustrated in
If the angle is within the target range in step 510, the method 500 may proceed to step 512 where the controller 196 generates and transmits a control command signal to notify the operator of the machine 102, an operator of the material receptacle 106, or both, that the machine 102 and the material receptacle 106 are sufficiently aligned to proceed with unloading material 108 from the implement 130 to the material receptacle 106. As discussed in more detail below, given sufficient alignment of the machine 102 with the material receptacle 106, unloading of material 108 from the implement 130 to the material receptacle may proceed under manual control of the machine 102 operator, manual control inputs from the operator of the machine 102 that are either overridden or modified by the controller 196, or under completely automatic control of the controller 196.
If the distance is not less than a threshold distance in step 506, or if the angle is not within the target range in step 510, the method 500 may proceed to step 514 where the controller 196 generates and transmits a control command signal to notify the operator of the machine 102, an operator of the material receptacle 106, or both, that the machine 102 and the material receptacle 106 are not sufficiently aligned to proceed with unloading material 108 from the implement 130 to the material receptacle 106. If the machine 102 and the material receptacle 106 are not sufficiently aligned, then the operator of the material receptacle 106 may move the material receptacle 106 relative to the work surface 104 to attempt to effect sufficient alignment with the machine 102. Alternatively or additionally, the material receptacle 106 may remain stationary with respect to the work surface 104, and the operator of the machine 102 may operate the propulsion system 116, the implement system 118, or both of the machine 102 to manually align the machine 102 with the material receptacle 106 and then unload material 108 from the implement 130 to the material receptacle 106.
The notification in either of steps 512 or 514 may be an audible notification, a visual notification, combinations thereof, or any other notification form known in the art. For example, the controller 196 may cause a horn of the machine 102 to honk to notify an operator of the material receptacle 106 of alignment in step 512. Alternatively or additionally, a visual or audible indicator may be triggered within an operator cab of the machine 102, the material receptacle 106, or both, as part of steps 512 or 514.
From either step 512 or step 514, the method 500 ends at step 516. However, it will be appreciated that other methods or functions may precede, follow, or be interspersed with the steps expressly outlined in method 500.
As shown in
According to an aspect of the disclosure, the width 552 of the autoload trigger zone 550 is less than an overall length of the machine 102 along the forward direction 152. According to another aspect of the disclosure, the height of the autoload trigger zone 550 extends from below the material receptacle 106 to above the material receptacle 106 along the vertical direction 150.
Upon detecting that the implement 130 is disposed within the autoload trigger zone 550, the controller 196 may generate and transmit a control signal that notifies the operator of the machine 102 that the implement 130 is disposed within the autoload trigger zone 550. The notification of the operator may take the form of a visual notification on a display of the machine 102, an audible notification generated within the operator cab 192, combinations thereof, or any other form of operator notification known in the art.
According to an aspect of the disclosure, the controller 196 may wait for an additional command control signal from the operator, after identifying that the implement 130 is located within the autoload trigger zone 550, before initiating an automatic procedure to unload material 108 from the implement 130 that begins with step 522. According to another aspect of the disclosure, the controller 196 may automatically initiate an automatic unloading procedure, which begins with step 522, upon identifying that the implement 130 is located within the autoload trigger zone 550, without further input from the operator.
In step 522, the controller automatically actuates the propulsion system 116, the implement system 118, or both, to locate the implement 130 at a target unloading location above the material receptacle 106. It will be appreciated that the alignment verification method 500 (see
As shown in
The target unloading location 210 may be disposed a vertical distance 556 above the top edge 160 of the material receptacle along the vertical direction 150, and a horizontal distance 558 from the proximate wall 180 (see
According to an aspect of the disclosure, selection of the vertical distance 556 may be based at least in part upon a variance or roughness of the work surface 104 along the vertical direction 150, to provide sufficient margin to avoid unintended contact between the machine 102 and the material receptacle 106. For example, an operator may want more vertical margin between the target unloading location 210 and the material receptacle 106 for rougher work surface 104 conditions. According to another aspect of the disclosure, the controller 196 may be configured to determine a variance or roughness of the work surface 104 along the vertical direction 150 from data collected from the perception system 120, and then use the variance or roughness of the work surface 104 as part of an algorithm for determining the vertical distance 556.
The horizontal distance 558 may be selected to avoid unintended contact between the implement 130 and the material receptacle 106 during the unloading of material 108 from the implement 130 to the material receptacle 106. According to an aspect of the disclosure, the horizontal distance 558 may be selected to locate the third pivot joint 148 above the aperture 554 of the material receptacle 106.
Returning to
Returning to
During any one of steps 520, 522, and 524, the controller 196 may be configured to store a location of the material receptacle 106, in the reference frame of the work surface 104, in memory 200 based on data input from the perception system 120. Additionally, the controller 196 may be configured to store the shape, the size, the three-dimensional geometry, or combinations thereof, of the material receptacle 106 in memory 200, which may help mitigate the effect of measurement variances with respect to the determined location of the material receptacle 106 relative to the work surface 104 or the machine 102.
Next, in step 528, the controller 196 may detect the end of a loading and unloading cycle and index the cycle counter unit 204 by one cycle. According to an aspect of the disclosure, the controller 196 may be configured to vary the vertical distance 556, the horizontal distance 558, or both, as a function of the number of unloading cycles delivered to the material receptacle 106 to achieve a target distribution of material 108 within the material receptacle 106, to compensate for increasing height of material 108 within the material receptacle 106 with successive cycles, or combinations thereof. For example, the controller 196 may be configured to increase the vertical distance 556 with increasing count value from the cycle counter unit 204 that is associated with an operation to fill a particular material receptacle 106 to avoid contact between the implement 130 and material 108 previously unloaded into the material receptacle 106. Alternatively or additionally, the controller 196 may be configured to alternate the horizontal distance 558 between a larger value and a smaller value with increasing count value from the cycle counter unit 204 to promote a desired distribution of material 108 within the material receptacle 106 along the forward direction 152.
If the material receptacle 106 is determined not to be full, then the method 412 may proceed to step 530, where the machine 102 travels to a source of material 108, and then loads material 108 from the source to the implement in step 532. During step 532, the controller 196 may store a location of the material source, in the reference frame of the work surface 104, in memory 200 using data collected from the perception system 120. Then, using stored locations for the material source and the material receptacle 106, the controller 196 may be configured to estimate a time of travel, a distance of travel, or both, between the material source and the material receptacle 106.
Next, in step 534, the machine 102 may return to the material receptacle 106 to begin unloading the material 108 from the implement 130 into the material receptacle 106 beginning with step 520. It will be appreciated that the steps 530, 532, and 534 may be performed with the machine 102 being operated in a purely manual mode, the machine 102 being operated in an automatic mode, the machine 102 being operated in a manual mode with override assistance from the controller 196, or combinations thereof.
After the start at step 602, the method 600 proceeds to step 604 where a horizontal velocity component of the implement 130 and a vertical velocity component of the implement 130 are determined in a reference frame of the work surface 104. For example, as shown in
Returning to
Returning to
In step 614, the vertical time of flight is compared to the horizontal time of flight. If the vertical time of flight is less than the horizontal time of flight, then there is no predicted or imminent contact between the implement 130 and the material receptacle 106, and the method 600 proceeds to the end at step 618 because no control signal intervention is required by the controller 196 to avoid contact between the implement 130 and the material receptacle 106.
However, if the vertical time of flight is not less than the horizontal time of flight, then there is predicted or imminent contact between the implement 130 and the material receptacle 106, and the method 600 proceeds to step 616, where the controller 196 overrides or modifies the operator's manual control command signals to better avoid contact between the implement 130 and the material receptacle 106. To avoid the predicted contact, the controller 196 may act to slow the horizontal velocity 650 of the implement 130, increase the vertical velocity component 652 of the implement 130, or combinations thereof.
The controller 196 may act to slow the horizontal velocity 650 of the implement by applying the at least one braking device 128, opening a clutch in the at least one transmission mechanism 124, downshifting to a lower gear in the at least one transmission mechanism 124, reducing an output shaft speed of the power source 122, combinations thereof, or any other method known in the art for reducing the horizontal velocity component of an implement of a machine. Further, the controller 196 may act to increase the vertical velocity 652 of the implement 130 by increasing hydraulic power applied to the lift actuator 138, adjusting a position of the tilt linkage 140 via the tilt actuator 142, combinations thereof, or any other method known in the art for increasing the vertical velocity component of an implement of a machine.
For example, as shown in
It will be appreciated that the method 600 may be performed repetitively during an unloading cycle of the machine 102. For example, the method 600 may be performed during every clock cycle of the controller 196, or performed during integer multiples of the clock cycle of the controller 196. According to an aspect of the disclosure, the method 600 may be performed at a frequency that is greater than 1 Hertz. Thus, the controller 196 may be configured to continuously correct a predicted path 660 of the implement 130 to avoid unintended contact between the machine 102 and the material receptacle 106.
When the leading edge 166 of the implement 130 is disposed within the first control override zone 700, as shown in
When the leading edge 166 of the implement 130 is disposed within the second control override zone 702, as shown in
The first control override zone 700 may at least partially overlap with the autoload trigger zone 550 (see
The first control override zone 700 may extend a horizontal distance 704 from an external surface 706 of the material receptacle 106 along the forward direction 152, and may extend above and below the top edge 160 of the material receptacle 106 along the vertical direction 150. The second control override zone 702 may extend a horizontal distance 708 from an internal surface 710 of the material receptacle 106 along the forward direction 152, and may extend above and below the top edge 160 of the material receptacle 106 along the vertical direction 150.
The first control override zone 700, the second control override zone 702, or both may extend a vertical distance 712 above the top edge 160 of the material receptacle 106 to better avoid unintentional contact between the implement 130 and the material receptacle 106. The vertical distance 712 may be less than the vertical distance 556 from the top edge 160 of the material receptacle 106 to the target unloading location 210 (see
A width of the first control override zone 700, the second control override zone 702, or both, may taper down along the vertical direction 150. According to an aspect of the disclosure, a width of the first control override zone 700 may taper down from the horizontal distance 704 to a point 714, which is disposed above the top edge 160 of the material receptacle 106, along the vertical direction 150. According to another aspect of the disclosure, a width of the second control override zone 702 may taper down from the horizontal distance 708 to a point 716, which is disposed above the top edge 160 of the material receptacle 106, along the vertical direction. The first control override zone 700, the second control override zone 702, or both, may have a triangular shape in a plane defined by the vertical direction 150 and the forward direction 152.
It will be appreciated that the controller 196 logic pertaining to the first control override zone 700, the second control override zone 702, or both, may be combined with the method 400 (see
It will be appreciated that the foregoing description provides examples of the disclosed system and technique. However, it is contemplated that other implementations of the disclosure may differ in detail from the foregoing examples. All references to the disclosure or examples thereof are intended to reference the particular example being discussed at that point and are not intended to imply any limitation as to the scope of the disclosure more generally. All language of distinction and disparagement with respect to certain features is intended to indicate a lack of preference for those features, but not to exclude such from the scope of the disclosure entirely unless otherwise indicated.
Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context.
Any of the methods or functions described herein may be performed by or controlled by the controller 196. Further, any of the methods or functions described herein may be embodied in a computer-readable non-transitory medium for causing the controller 196 to perform the methods or functions described herein. Such computer-readable non-transitory media may include magnetic disks, optical discs, solid state disk drives, combinations thereof, or any other computer-readable non-transitory medium known in the art. Moreover, it will be appreciated that the methods and functions described herein may be incorporated into larger control schemes for an engine, a machine, or combinations thereof, including other methods and functions not described herein, and that any of the methods or method steps described may be combined, either in part or in their entireties, unless specified otherwise.
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