Work machine control device

Abstract

During excavation and dumping work, it processes soil that has accumulated close to the work machine. [Solution] A control device for a work machine comprises an operation determination unit that determines whether or not to perform a soil-pushing operation using the back surface of the bucket to push soil farther from the work machine based on terrain information, an operation planning unit that plans a bucket trajectory based on the determination of the operation determination unit, and an automatic operation control unit that operates the bucket based on the bucket trajectory planned by the operation planning unit. The operation determination unit determines whether or not to perform a soil-pushing operation to move soil from a first area set around the work machine to a second area that is farther from the work machine than the first area, based on terrain information, the operation planning unit plans a bucket trajectory for the soil-pushing operation if the operation determination unit determines that the soil-pushing operation is performable, and the automatic operation control unit controls the operation of the bucket to perform the soil-pushing operation according to the bucket trajectory planned by the operation planning unit.

Description

[Technical Field]

[0001] The present invention relates to a control device for a work machine that automatically performs excavation and earth dumping work, for example. [Background technology]

[0002] Excavation and dumping work involves excavating earth and sand using a work machine (e.g., a hydraulic excavator) equipped with a work implement (e.g., a front work implement) driven by a hydraulic actuator, and dumping the earth and sand onto a transport vehicle (e.g., a dump truck) equipped with a transporting device (e.g., a vessel).

[0003] Research is being conducted into how to automatically control such excavation and dumping operations. In order for a work machine to perform excavation work, it is necessary to determine the position on the object to be excavated and the trajectory to be excavated. In addition, it is also possible to shape the object into a shape that makes it easier to excavate in order to excavate efficiently.

[0004] Patent Document 1 discloses a technique for selecting an excavation position based on the volume of soil and sand. The technique in Patent Document 1 obtains a set of excavation points from the height of the soil and sand. The technique in Patent Document 1 determines whether there is an excavation trajectory of the bucket of the work machine that will not collide with obstacles while moving and whose excavation resistance is equal to or less than the excavation power of the work machine. The excavation trajectory is a set of excavation points. The technique in Patent Document 1 calculates the soil volume of candidate excavation points based on the parameters of the excavation trajectory, and selects a target excavation point based on the soil volume of the candidate excavation points.

[0005] Patent Document 2 discloses a technique for generating a bucket trajectory when a work machine excavates, based on information on the pile height of earth and the range of motion of the work machine during excavation. The technique in Patent Document 2 acquires information on the excavation site where earth and sand will be excavated, and generates a bucket trajectory when the work machine excavates earth and sand, based on information on the pile height of the object at the excavation site and the range of motion of the work machine during excavation.

[0006] Patent Document 3 discloses a technology for determining the destination of sediment based on the sediment accumulation status. The technology in Patent Document 3 evaluates the ease of excavation based on the sediment accumulation status and determines the destination of the sediment. In other words, the technology in Patent Document 3 shapes the sediment into a shape that is easy to excavate. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent No. 6926172 [Patent Document 2] Patent No. 7248122 [Patent Document 3] International Publication No. 2022 / 180843 Summary of the Invention [Problem to be solved by the invention]

[0008] However, none of the technologies in Patent Documents 1, 2, and 3 take into consideration the fact that earth and sand accumulates closer to the work machine as excavation and dumping operations are repeated. In an excavation operation using a work machine such as a typical backhoe, the bucket is moved from a position far from the work machine to a position close to the work machine to scoop up earth and sand, so earth and sand that does not enter the bucket accumulates closer to the work machine. If the earth and sand accumulates close to the body of the work machine, the bucket cannot scoop up the earth and sand.

[0009] An object of the present invention is to provide a control device for a work machine that is capable of disposing of earth and sand that has gathered in a position close to the work machine during excavation and dumping work. [Means for solving the problem]

[0010] The work machine control device of the present invention, which solves the above-mentioned problems, is a control device for a work machine equipped with a bucket, and comprises: a current terrain acquisition unit that acquires terrain information around the work machine; an operation determination unit that determines whether or not to perform a soil-pushing operation in which the back of the bucket is used to push soil away from the work machine based on the terrain information acquired by the current terrain acquisition unit; a operation planning unit that plans a bucket trajectory based on the determination of the operation determination unit; and an automatic operation control unit that operates the bucket based on the bucket trajectory planned by the operation planning unit, wherein the operation determination unit determines whether or not to perform a soil-pushing operation in which soil is moved from a first area set around the work machine to a second area that is farther from the work machine than the first area, based on the terrain information, and the operation planning unit plans a bucket trajectory for the soil-pushing operation when the operation determination unit determines that the soil-pushing operation can be performed, and the automatic operation control unit controls the operation of the bucket to perform the soil-pushing operation according to the bucket trajectory planned by the operation planning unit. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a control device for a work machine that is capable of disposing of soil that has gathered in a position close to the work machine during excavation and soil dumping work. Further features related to the present invention will become apparent from the description of the present specification and the accompanying drawings. In addition, the problems, configurations, and effects other than those described above will become apparent from the following description of the embodiments. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. [Figure 2] FIG. 2 is a diagram showing a control device for a work machine together with a hydraulic drive system. [Figure 3] FIG. 2 is a functional block diagram of a control device according to the first embodiment. [Figure 4] FIG. 4 is a functional block diagram of an operation determination unit in FIG. 3 according to the first embodiment. [Figure 5] 4 is a flowchart of the operation of the control device in the first embodiment. [Figure 6] 6 is a flowchart showing a process for determining whether or not pushing of earth is possible in FIG. 5 in the first embodiment. [Figure 7] FIG. 2 is a plan view of the first region and the second region. [Figure 8] FIG. 10 is a plan view of the earth-pushing operation of the first embodiment. [Figure 9] FIG. 10 is a functional block diagram of a control device according to a second embodiment. [Figure 10] FIG. 10 is a functional block diagram of an operation determination unit in FIG. 9 according to the second embodiment. [Figure 11] 10 is a flowchart of the operation of the control device in the second embodiment. [Figure 12] FIG. 10 is a plan view of the earth-pushing operation of the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. While the following will illustrate a hydraulic excavator equipped with a bucket as a working implement (attachment) at the tip of the working device, the present invention may also be applied to a working machine equipped with an attachment other than a bucket. Furthermore, the present invention may be applied to a working machine other than a hydraulic excavator, as long as it has an articulated working device configured by connecting multiple link members (attachments, arms, booms, etc.).

[0014] Furthermore, in this specification, with regard to the meaning of the words "on," "above," or "below" when used in conjunction with a term indicating a certain shape (e.g., target surface, design surface, etc.), "on" means the "surface" of the certain shape, "above" means a "position higher than the surface" of the certain shape, and "below" means a "position lower than the surface" of the certain shape.

[0015] First Embodiment <Basic configuration> Fig. 1 is a configuration diagram of a work machine 1 according to the first embodiment, and Fig. 2 is a diagram showing a control device 40A of the work machine 1 according to the first embodiment together with a hydraulic drive unit 50. As will be described later, the control device 40A of this embodiment determines whether to perform an excavation operation in which the bucket of the work machine 1 is used to scoop up earth and sand, or an earth-pushing operation in which the back surface of the bucket is used to push earth and sand away from the work machine 1. More specifically, the control device 40A determines whether to perform an earth-pushing operation in which earth and sand are moved from a first area, which includes an area that does not overlap with a second area, to a second area that is farther away from the work machine 1 than the first area, based on topographical information.

[0016] 1, the work machine 1, which is a hydraulic excavator, is made up of an articulated front working implement 1A and a vehicle body 1B. The vehicle body 1B is made up of a lower traveling body 11 that travels using a pair of left and right traveling hydraulic motors 3a and 3b, and an upper rotating body 12 that is attached to the lower traveling body 11 and rotates using a swing hydraulic motor 4.

[0017] The front working mechanism 1A is configured by connecting a plurality of driven members (a boom 8, an arm 9, and a bucket 10) that each rotate vertically. The base end of the boom 8 is rotatably supported via a boom pin at the front of the upper rotating body 12. An arm 9 is rotatably connected to the tip of the boom 8 via an arm pin, and a bucket 10 is rotatably connected to the tip of the arm 9 via a bucket pin. The boom 8 is driven by a boom cylinder 5, the arm 9 is driven by an arm cylinder 6, and the bucket 10 is driven by a bucket cylinder 7. In this embodiment, the back surface 10b of the bucket is also used to remove soil and sand.

[0018] An engine 18, which is a prime mover mounted on the upper rotating body 12, drives a hydraulic pump 2. As shown in Fig. 2, the hydraulic pump 2 is made up of hydraulic pumps 2a and 2b, which are variable displacement pumps. A hydraulic drive system 50 is made up of the engine 18, hydraulic pumps 2a and 2b, a pilot pump 48, an electromagnetic proportional valve unit 160, flow control valves 15a, 15b, 15c, 15d, 15e, and 15f, a traveling hydraulic motor 3a, a traveling hydraulic motor 3b, a swing hydraulic motor 4, a boom cylinder 5, an arm cylinder 6, and a bucket cylinder 7.

[0019] The capacities of hydraulic pumps 2a and 2b are controlled by regulators 2aa and 2ba. The pressure oil discharged from hydraulic pumps 2a and 2b is supplied via flow control valves 15a, 15b, 15c, 15d, 15e, and 15f to traveling hydraulic motor 3a, traveling hydraulic motor 3b, swing hydraulic motor 4, boom cylinder 5, arm cylinder 6, and bucket cylinder 7. Flow control valves 15a, 15b, 15c, 15d, 15e, and 15f are hydraulic pilot-type directional changeover valves.

[0020] The engine 18 drives the pilot pump 48. The pressurized oil discharged from the pilot pump 48 is supplied to the electromagnetic proportional valve unit 160 via the pump line 130 and the lock valve 39. The lock valve 39 shuts off the pump line 130 so that the work machine 1 will not operate even if the right operating lever 1a, the left operating lever 1b, the right traveling lever 23a, and the left traveling lever 23b in the operator's cab provided on the upper rotating body 12 shown in Figures 1 and 2 are operated by mistake when the work machine 1 is not performing work.

[0021] The electromagnetic proportional valve unit 160 shown in Figures 1 and 2 reduces the pressure of the pressure oil supplied from the pilot pump 48 using a plurality of electromagnetic proportional valves to generate pilot hydraulic pressure signals, and supplies the signals to pressure receiving sections 150a, 150b, 151a, 151b, 152a, 152b, 153a, 153b, 154a, 154b, 155a, 155b via pilot lines 140a, 140b, 141a, 141b, 142a, 142b, 143a, 143b, 144a, 144b, 145a, 145b.

[0022] The switching direction and opening of flow control valves 15a, 15b, and 15c are controlled by the pilot hydraulic signals supplied to pressure receiving sections 150a to 152b, and the direction and flow rate of pressurized oil flowing in and out of boom cylinder 5, arm cylinder 6, and bucket cylinder 7 are controlled. Boom cylinder 5, arm cylinder 6, and bucket cylinder 7 extend and contract in accordance with the direction and flow rate of pressurized oil flowing in and out, causing boom 8, arm 9, and bucket 10 to rotate, respectively, and changing the position and attitude of bucket 10.

[0023] Furthermore, the pilot hydraulic signal supplied to the pressure receiving parts 153a, 153b controls the switching direction and opening degree of the flow control valve 15d, thereby controlling the direction and flow rate of pressure oil flowing in and out of the swing hydraulic motor 4. The swing hydraulic motor 4 rotates in accordance with the direction and flow rate of pressure oil flowing in and out, causing the upper swing body 12 to swing relative to the lower traveling body 11. The pilot hydraulic signal supplied to the pressure receiving parts 154a to 155b controls the switching direction and opening degree of the flow control valves 15e, 15f, thereby controlling the direction and flow rate of pressure oil flowing in and out of the traveling hydraulic motor 3a and the traveling hydraulic motor 3b. The pressure oil supplied by the flow control valves 15e, 15f rotates the traveling hydraulic motor 3a and the traveling hydraulic motor 3b, causing the lower traveling body 11 to travel.

[0024] The swing hydraulic motor 4, boom cylinder 5, arm cylinder 6, and bucket cylinder 7 are provided with pressure sensors 16a, 16b, 16c, 16d, 16e, 16f, 16k, and 16l to detect their operating pressures. The pressure sensors 16a to 16f and 16k to 16l detect the pressures in the input and output lines of the swing hydraulic motor 4, and the pressures on the bottom and rod sides of the boom cylinder 5, arm cylinder 6, and bucket cylinder 7, respectively, and output these as electrical signals to the control device 40A. Note that in FIG. 2, the connection lines from the pressure sensors 16a to 16f and 16k to 16l to the control device 40A are not shown due to space limitations.

[0025] Pressure sensors 16g, 16h, 16i, and 16j are provided in the flow paths connecting the travel hydraulic motor 3a and the travel hydraulic motor 3b with the flow control valves 15e and 15f so that the operating pressures of the travel hydraulic motor 3a and the travel hydraulic motor 3b can be detected. The pressure sensors 16g to 16j detect the pressures in the input and output lines of the travel hydraulic motor 3a and the travel hydraulic motor 3b, and output the detected pressures as electrical signals to the control device 40A. Note that in FIG. 2, the connection lines from the pressure sensors 16g to 16j to the control device 40A are not shown due to space limitations.

[0026] In automatic operation control, flow control valves 15a, 15b, 15c, 15d, 15e, and 15f are driven by pilot hydraulic signals from a plurality of electromagnetic proportional valves in electromagnetic proportional valve unit 160, and operate traveling hydraulic motor 3a, traveling hydraulic motor 3b, swing hydraulic motor 4, boom cylinder 5, arm cylinder 6, and bucket cylinder 7. The electromagnetic proportional valves inside electromagnetic proportional valve unit 160 are controlled by control commands from control device 40A.

[0027] A boom angle sensor 30 is attached to the boom 8, an arm angle sensor 31 to the arm 9, and a bucket angle sensor 32 to the bucket link 13 so that the rotation angles of the boom 8, arm 9, and bucket 10 can be detected. A vehicle body inclination angle sensor 33 is attached to the upper rotating body 12 so that the inclination angle of the upper rotating body 12 (vehicle body 1B) with respect to a reference plane (e.g., a horizontal plane) can be detected. A vehicle body position detection device 36 is attached to the upper rotating body 12 so that the position of the vehicle body 1B can be detected. A swing angle sensor 34 is attached to the swing center axis of the upper rotating body 12 with respect to the lower running body 11 so that the relative angle θ between the upper rotating body 12 and the lower running body 11 can be detected.

[0028] A right travel lever 23a for operating the travel hydraulic motor 3a and a left travel lever 23b for operating the travel hydraulic motor 3b are provided in a cab provided on the upper rotating body 12. A right operating lever 1a for operating the boom cylinder 5 (boom 8) and the bucket cylinder 7 (bucket 10) and a left operating lever 1b for operating the arm cylinder 6 (arm 9) and the swing hydraulic motor 4 (upper rotating body 12) are provided in a cab provided on the upper rotating body 12.

[0029] The right operating lever 1a, the left operating lever 1b, the right traveling lever 23a, and the left traveling lever 23b are electric levers that generate electric signals according to the amount and direction of operation by the operator. The electric signals thus generated are input to the control device 40A, and the control device 40A outputs electric signals to the solenoid proportional valve unit 160 to drive the solenoid proportional valves of the solenoid proportional valve unit 160 in accordance with the operation input to the right operating lever 1a, the left operating lever 1b, the right traveling lever 23a, and the left traveling lever 23b. The pilot pressure oil generated by the solenoid proportional valves of the solenoid proportional valve unit 160 is supplied to the pressure receiving portions 150a to 155b of the corresponding flow control valves 15a to 15f via pilot lines 140a to 145b in accordance with the input electric signals, and is used as a control signal to drive these flow control valves 15a to 15f.

[0030] Fig. 3 is a functional block diagram of the control device 40A in the first embodiment. The work implement attitude detection device 60 shown in Fig. 3 is composed of a boom angle sensor 30, an arm angle sensor 31, a bucket angle sensor 32, and a vehicle body inclination angle sensor 33. The boom angle sensor 30, the arm angle sensor 31, the bucket angle sensor 32, and the vehicle body inclination angle sensor 33 function as attitude sensors for the front work implement 1A.

[0031] The terrain detection device 70 is made up of distance measurement sensors 70a and 70b shown in Figure 1. The terrain detection device 70 detects the terrain around the work machine 1 by measuring the distance to the ground around the work machine 1 using these distance measurement sensors 70a and 70b. In this embodiment, the terrain detection device 70 is mounted on the work machine 1, but the terrain detection device 70 may also be installed at a construction site or on another machine such as a drone. Furthermore, the types of sensors that make up the terrain detection device 70 may be sensors other than distance measurement sensors, such as LiDAR and stereo cameras, and the number of sensors is not limited to the above.

[0032] <Solenoid proportional valve unit> The electromagnetic proportional valve unit 160 is composed of electromagnetic proportional valves. When not energized, the electromagnetic proportional valves have a minimum opening, and the opening increases as the current, which is a control signal from the control device 40A, increases. In this way, the opening of each electromagnetic proportional valve in the electromagnetic proportional valve unit 160 corresponds to the control signal from the control device 40A.

[0033] In the electromagnetic proportional valve unit 160 configured as described above, when the electromagnetic proportional valve is driven by a control signal from the control device 40A, pilot pressure can be generated even when the operator does not operate the corresponding right operating lever 1a, left operating lever 1b, right traveling lever 23a, and left traveling lever 23b, so that the operation of the traveling hydraulic motor 3a, the traveling hydraulic motor 3b, the swing hydraulic motor 4, the boom cylinder 5, the arm cylinder 6, and the bucket cylinder 7 can be forcibly generated.

[0034] <External system> The external system 200 shown in Figure 3 is made up of a user interface device used by the manager of the work machine 1, a management system server, etc. Note that the term "server" refers to a processing device that can send and receive information to and from a communication device via a communication line, etc., and does not refer to hardware such as a personal computer or embedded information device. The manager issues task information, which will be described later, to the work machine 1 via the user interface device. Alternatively, task information may be issued directly from the management system server, etc. to the work machine 1. The user interface device, management system server, etc. are equipped with a monitor, and can display information related to the automatic operation of the work machine 1.

[0035] <Control device> As described above, Figure 3 is a functional block diagram of the control device 40A. The control device 40A includes a position and attitude calculation unit 43b, an electromagnetic proportional valve control unit 44, an actuator control unit 81, a motion planning unit 90, an automatic motion control unit 91, an input unit 100, a current topography acquisition unit 102, and a motion determination unit 111A. The control device 40A of the work machine 1 controls the excavation operation of scooping up earth and sand using the bucket 10 of the work machine 1.

[0036] Task information is input to the input unit 100 from the external system 200. Task information is information that indicates the content of the work to be performed by the work machine 1. In this embodiment, the task to be performed is an excavation and soil dumping task, and the task information includes information on the position and size of a third area, which is an area where the excavation operation is to be performed. Furthermore, the task information may include, for example, information on whether, in the excavation operation, the work machine 1 will perform the excavation operation while proceeding toward the excavation position (for example, while moving forward), or while proceeding toward the opposite side of the excavation position (for example, while moving backward).

[0037] In this embodiment, the fourth area, which is an area where earth-pushing operations described below are performed, is also provided as task information from the external system 200, just like the third area. However, the fourth area may be automatically set by the control device 40A based on the positional relationship between the third area and the range within which the bucket 10 can move due to the rotational operation of the front working implement 1A and the swinging operation of the upper swing body 12.

[0038] The position and attitude calculation unit 43b calculates the position coordinates of the work machine 1, the attitude of the front work implement 1A, and the position of the toe of the bucket 10 based on information from the work implement attitude detection device 60 and the vehicle body position detection device .

[0039] The current terrain acquisition unit 102 acquires and calculates terrain information around the work machine 1 based on information from the terrain detection device 70.

[0040] The operation determination unit 111A determines whether to perform an excavation operation or an earth-pushing operation in which the bucket back surface 10b of the bucket 10 is used to push earth away from the work machine 1, based on the topography information acquired by the current topography acquisition unit 102. The operation determination unit 111A determines whether to perform an earth-pushing operation or an excavation operation based on information from the input unit 100 and the current topography acquisition unit 102, and outputs the result to the operation planning unit 90.

[0041] The motion planning unit 90 plans the trajectory of the bucket 10 during the earth-pushing operation and the excavation operation based on the judgment of the operation judgment unit 111A. Based on the task information acquired from the input unit 100 and the excavation start position and excavation end position set by the operation judgment unit 111A, the motion planning unit 90 calculates the position coordinates of the work machine 1 at each time of the operation of moving the bucket 10 to the earth-discharging position, the attitude of the front working implement 1A, and the trajectory of the position of the toe of the bucket 10, and outputs these to the automatic operation control unit 91.

[0042] The automatic movement control unit 91 operates the bucket 10 based on the trajectory of the bucket 10 planned by the movement planning unit 90. The automatic movement control unit 91 calculates target movement speeds for the traveling hydraulic motor 3a, traveling hydraulic motor 3b, swing hydraulic motor 4, boom cylinder 5, arm cylinder 6 and bucket cylinder 7 based on information relating to the planned trajectory of the bucket 10 from the movement planning unit 90, and information relating to the position coordinates of the work machine 1, the attitude of the front working implement 1A and the position of the toe of the bucket 10 from the position and attitude calculation unit 43b, and outputs the calculated speeds to the actuator control unit 81.

[0043] The actuator control unit 81 calculates target pilot pressures for the flow control valves 15a, 15b, 15c, 15d, 15e, and 15f of the traveling hydraulic motor 3a, traveling hydraulic motor 3b, swing hydraulic motor 4, boom cylinder 5, arm cylinder 6, and bucket cylinder 7 based on the target operation speeds of the traveling hydraulic motor 3a, traveling hydraulic motor 3b, swing hydraulic motor 4, boom cylinder 5, arm cylinder 6, and bucket cylinder 7 output from the automatic operation control unit 91.

[0044] The actuator control section 81 outputs the calculated target pilot pressure to the electromagnetic proportional valve control section 44. The electromagnetic proportional valve control section 44 outputs currents that are control signals to the electromagnetic proportional valves (not shown) of the electromagnetic proportional valve unit 160, based on the target pilot pressures for the flow control valves 15a, 15b, 15c, 15d, 15e, and 15f output from the actuator control section 81.

[0045] Fig. 4 is a functional block diagram of the operation determination unit 111A in Fig. 3 in the first embodiment. The operation determination unit 111A includes a temporary earth-pushing start position setting unit 117, an earth-pushing start position calculation unit 118, a determination unit 119A including an earth-pushing start position determination unit 119a and a provisional start position determination unit 119b, and an earth-pushing start position setting unit 120.

[0046] The earth-pushing start position temporary setter 117 temporarily sets the earth-pushing start position in a first region within a fourth region, which is the region where the earth-pushing operation is performed, based on information from the input unit 100. The first region is determined based on the range (movable range) within which the bucket 10 can move due to the rotational movement of the front working implement 1A and the swinging movement of the upper rotating body 12, and the trajectory that the bucket 10 can take during the earth-pushing operation. Furthermore, the earth-pushing start position temporary setter 117 temporarily sets the earth-pushing end position in a second region within a third region, which is the region where the excavation operation is performed, based on information from the input unit 100 and information related to the temporarily set earth-pushing start position.

[0047] The sediment volume calculation unit 118 calculates the volume of sediment being pushed at the landslide start position and the volume of sediment being pushed from the landslide start position to the landslide end position based on the topography information from the current topography acquisition unit 102 and information about the provisionally set landslide start position from the landslide start position provisional setting unit 117.

[0048] The sediment volume determination unit 119a determines whether the volume of sediment of the sediment pushing target at the sediment pushing start position and the volume of sediment of the sediment pushing target from the sediment pushing start position to the sediment pushing end position in the second region satisfy the conditions for determining that the sediment pushing operation is executable, based on information from the sediment volume calculation unit 118. The second region is determined based on the movable range of the bucket 10 and the excavation trajectory that the bucket 10 can take during the excavation operation.

[0049] As will be described later, the provisional start position determination unit 119b repeatedly calculates the earthdriving start position while changing the earthdriving start position held as a temporarily set provisional start position, and determines whether or not to update the earthdriving start position held as a provisional start position based on the distance of the earthdriving start position from the work machine 1, the volume of earthdriving target at the earthdriving start position, and the volume of earthdriving target from the earthdriving start position to the earthdriving end position. The earthdriving start position setting unit 120 sets the earthdriving start position based on information from the determination unit 119A.

[0050] <Action decision flow> Fig. 5 is a flowchart of the operation of the control device 40A in the first embodiment. As shown in Fig. 5, in S100, the input unit 100 acquires task information input from the external system 200, the task information including information on a third area where an excavation operation is performed and a fourth area where an earth-pushing operation is performed.

[0051] In S110, the current terrain acquisition unit 102 acquires terrain information about the surrounding area of ​​the work machine 1 from the terrain detection device 70. In this embodiment, the work machine 1 measures the surrounding terrain using the distance measuring sensors 70a, 70b of the terrain detection device 70, but terrain information measured by another measurement system may also be acquired from a server or the like. In S120, the operation determination unit 111A determines whether or not to perform earth-pushing based on the terrain information from the current terrain acquisition unit 102 and the task information from the input unit 100, and determines the next operation to be performed. In other words, the operation determination unit 111A determines whether or not to perform an earth-pushing operation that moves earth from a close area to a far area from the work machine 1, based on the terrain information.

[0052] In S160, the action determination unit 111A determines whether or not the start position of pushing the earth, which is determined to be executable in S120, exists within the first area included in the fourth area. If the determination in S160 is YES, the action determination unit 111A proceeds to S170, and if the determination is NO, the action determination unit 111A proceeds to S180.

[0053] In S170, if the determination in S160 is YES, the motion planning unit 90 plans a trajectory of the bucket 10 for the earth-pushing operation, regardless of whether the excavation operation can be performed. The automatic operation control unit 91 operates the bucket 10 to perform the earth-pushing operation. In S180, if the determination in S160 is NO, the motion planning unit 90 plans a trajectory of the bucket 10 for the excavation operation. The automatic operation control unit 91 operates the bucket 10 to perform the excavation operation.

[0054] The above operations from S100 to S180 are performed each time task information is acquired by the input unit 100. Therefore, the operation determination unit 111A determines whether or not the earth-pushing operation can be performed after the series of operations from the excavation operation to the release of soil, for which the operation planning unit 90 has planned the trajectory of the bucket 10, or the earth-pushing operation, has been completed, but before the operation planning unit 90 plans the next trajectory of the bucket 10.

[0055] <Flow of determining whether to push sand> Fig. 6 is a flowchart of the determination S120 of whether or not to perform pushing of earth in Fig. 5 in the first embodiment. Fig. 7 is a plan view of the first and second regions. Fig. 8 is a plan view of the pushing operation of the first embodiment. First, the first region R1, the second region R2, the third region R3, and the fourth region R4 will be described.

[0056] 7, the first region R1 is determined based on the movable range R0 of the bucket 10 and the trajectory that the bucket 10 can take during earth-pushing operation. The second region R2 is determined based on the movable range R0 of the bucket 10 and the trajectory that the bucket 10 can take during excavation operation. Both the first region R1 and the second region R2 are circular with a smaller maximum radius and a larger minimum radius than the circular range R0 of the bucket 10.

[0057] The first region R1 and the second region R2 have overlapping areas. Furthermore, the first region R1 has areas that do not overlap with the second region. The second region R2 is farther away from the work machine 1 than the first region R1. Furthermore, the first region R1 has a circular shape with smaller maximum and minimum radii than the second region R2.

[0058] This is because the earth-pushing operation moves the bucket 10 from the front to the back as seen from the work machine 1, so the earth-pushing operation can be started from further forward. For this reason, the first region R1 is a circle with a smaller minimum radius than the second region R2. On the other hand, if an earth-pushing operation is to be started from further back, it is not possible to ensure the distance required for the earth-pushing operation to push the bucket 10 back within the movable range R0. For this reason, the first region R1 is a circle with a smaller maximum radius than the second region R2.

[0059] As shown in Figure 8, the third area R3 is an area where excavation operations are performed, including part of the second area R2. The task information input to the input unit 100 includes information on the position and size of the third area R3. In other words, the task information provides information on what kind of excavation operation will be performed by the work machine 1. When excavating the third area R3 input as task information to the input unit 100, a determination is made as to whether or not an earth-pushing operation can be performed and an earth-pushing start position is set. The operation determination unit 111A determines whether or not an earth-pushing operation can be performed, which pushes earth from the first area R1 into the second area R2 within the third area R3.

[0060] When the operation determination unit 111A determines that the earth-pushing operation of pushing earth and sand from the first area R1 to the second area R2 within the third area R3 is executable, the operation planning unit 90 plans a trajectory of the bucket 10 for the earth-pushing operation of pushing earth and sand from the first area R1 to the second area R2 within the third area R3. The automatic operation control unit 91 operates the bucket 10 to perform the earth-pushing operation of pushing earth and sand from the first area R1 to the second area R2 within the third area R3.

[0061] The fourth region R4 is a region including a part of the first region R1 where the earth-pushing operation is performed. The operation determination unit 111A determines whether or not the earth-pushing operation of pushing earth from the first region R1 in the fourth region R4 to the second region R2 in the third region R3 can be performed.

[0062] When the operation determination unit 111A determines that the earth-pushing operation of pushing earth and sand from the first area R1 in the fourth area R4 to the second area R2 in the third area R3 is executable, the operation planning unit 90 plans a trajectory of the bucket 10 for the earth-pushing operation of pushing earth and sand from the first area R1 in the fourth area R4 to the second area R2 in the third area R3. The automatic operation control unit 91 operates the bucket 10 to perform the earth-pushing operation of pushing earth and sand from the first area R1 in the fourth area R4 to the second area R2 in the third area R3.

[0063] The earth-pushing start position PS is the position in the first region R1 where the earth-pushing operation starts. For example, the earth-pushing start position PS can be determined to be the farthest end of the bucket 10 when the bucket 10 is positioned at the frontmost side of the first region as seen from the work machine 1. The volume of earth being pushed at the earth-pushing start position PS is determined by the volume of earth that exists above the contact surface of the undercarriage 11 of the work machine 1 in a rectangular region defined in a plan view by the width of the bucket 10 and an arbitrary length from the earth-pushing start position PS in the direction away from the work machine 1.

[0064] The given length from the earth-pushing start position PS in the direction away from the work machine 1 can be, for example, the same as the width of the bucket 10. However, the given length from the earth-pushing start position PS in the direction away from the work machine 1 may be smaller or larger than the width of the bucket 10. The volume of earth that is being pushed out by the earth-pushing operation at the earth-pushing start position PS is an index that indicates the volume of earth that will be pushed out by the earth-pushing operation. The volume of earth that is being pushed out by the earth-pushing operation at the earth-pushing start position PS is also an index that is used to determine whether or not it is necessary to perform earth-pushing operation.

[0065] The earth-pushing end position PE is the position where the earth-pushing operation ends. The earth-pushing end position PE can be determined, for example, to be the farthest end of the second area as seen from the work machine 1. The volume of earth that is the object of earth-pushing from the earth-pushing start position PS to the earth-pushing end position PE is determined by the volume of earth that exists above the contact surface of the undercarriage 11 of the work machine 1 in a rectangular area defined in a plan view by the width of the bucket 10 and the length from the earth-pushing start position PS to the earth-pushing end position PE.

[0066] The rectangular area defined by the width of the bucket 10 and the length from the earth-pushing start position PS to the earth-pushing end position PE is the range PSE from the earth-pushing start position PS to the earth-pushing end position PE. The range PSE is the range from the farthest end of the bucket 10 at the earth-pushing start position PS as seen from the work machine 1 to the farthest end of the bucket 10 at the earth-pushing end position PE as seen from the work machine 1. The volume of earth that is the object of earth-pushing from the earth-pushing start position PS to the earth-pushing end position PE is an index used to determine whether earth-pushing operation is possible.

[0067] The operation for determining whether or not to execute earth-pushing is described below. As shown in Fig. 6, in S200, the earth-pushing start position temporary setting unit 117 temporarily sets the earth-pushing start position PS in the first region R1 contained within the fourth region R4. The earth-pushing start position temporary setting unit 117 temporarily sets the earth-pushing end position PE in the second region R2 contained within the third region R3. In S210, the earth-pushing volume calculation unit 118 calculates the volume of earth-pushing target at the earth-pushing start position PS temporarily set in S200 based on the topography information from the current topography acquisition unit 102 and information related to the temporarily set earth-pushing start position PS from the earth-pushing start position temporary setting unit 117. The dimensions of the range for calculating the earth-pushing volume are determined based on the width dimension of the bucket 10, as described above.

[0068] In S220, the sediment volume calculation unit 118 calculates the volume of sediment that is subject to sediment pushing from the sediment pushing start position PS provisionally set in S200 to the sediment pushing end position PE based on the topography information from the current topography acquisition unit 102 and information about the provisionally set sediment pushing start position PS from the provisional sediment pushing start position setting unit 117.

[0069] In S230, the earth moving volume determination unit 119a determines whether the earth moving volume of the earth moving target at the earth moving start position PS calculated in S210 is equal to or greater than the first threshold. If the determination in S230 is YES, the operation determination unit 111A proceeds to S240, and if the determination is NO, the operation determination unit 111A proceeds to S320. In S230, it is determined whether the earth moving volume of the earth moving target at the earth moving start position PS is large enough to require earth moving operation.

[0070] The first threshold value is determined by experiment or simulation. The smaller the first threshold value, the more likely it is to be set at the earth-pushing start position PS even if the volume of earth being pushed at the earth-pushing start position PS is small. However, if the first threshold value is set too small, the time spent by the work machine 1 in earth-pushing operation will be longer and the time spent in excavation operation will be shorter, resulting in a decrease in the efficiency of excavation operation. Therefore, the first threshold value is determined from the perspective of the necessity for earth-pushing operation and the efficiency of excavation operation.

[0071] In S240, if the determination in S230 is YES, the earth and sand volume determination unit 119a determines whether the earth and sand volume of the earth and sand pushing target from the earth and sand pushing start position PS to the earth and sand pushing end position PE calculated in S220 is equal to or less than the second threshold value. If the determination in S240 is YES, the operation determination unit 111A proceeds to S250, and if the determination is NO, the operation determination unit 111A proceeds to S320.

[0072] In S240, it is determined whether the volume of the earth moving target from the earth moving start position PS to the earth moving end position PE is large enough to allow the earth moving operation. In other words, even if it is determined in S230 that the volume of the earth moving target at the earth moving start position PS is large enough to require the earth moving operation, if the volume of the earth moving target from the earth moving start position PS to the earth moving end position PE is large enough to make the earth moving operation impossible, the earth moving operation is impossible.

[0073] The second threshold value is determined by the output of the work machine 1 and the soil quality from the earth-pushing start position PS to the earth-pushing end position PE. This is because even if the force of the work machine 1 to push out earth and sand is sufficiently large, if the soil is soft, for example, the work machine 1 will slip due to the reaction force during the earth-pushing operation. Note that even if it is determined in S240 that the volume of earth being pushed from the earth-pushing start position PS to the earth-pushing end position PE is so large that earth-pushing operation is impossible, if the volume of earth in the second region R2 decreases due to subsequent excavation operation, it may still be determined that earth-pushing operation from that earth-pushing start position PS is executable.

[0074] In S250, if the determination in S240 is YES, the temporary start position determination unit 119b calculates the distance from the work machine 1 to the earth-pushing start position PS set in S200. In S260, the temporary start position determination unit 119b determines whether the distance from the work machine 1 to the earth-pushing start position PS calculated in S250 is equal to or less than the temporary minimum distance.

[0075] The provisional minimum distance means the shortest distance from the work machine 1 to each of the single or multiple provisional start positions that have been previously temporarily set. When the earth-pushing start position PS is provisionally set for the first time, the distance from the work machine 1 to the initially provisionally set earth-pushing start position PS becomes the provisional minimum distance. If the determination in S260 is YES, the operation determination unit 111A proceeds to S270, and if the determination is NO, the operation determination unit 111A proceeds to S320.

[0076] In S270, if the determination in S260 is YES, the temporary start position determination unit 119b determines whether the distance from the work machine 1 to the earth-pushing start position PS calculated in S250 is equal to the temporary minimum distance. If the determination in S270 is YES, the operation determination unit 111A proceeds to S280, and if the determination is NO, the operation determination unit 111A proceeds to S310. In other words, in S260 and S270, the operation determination unit 111A searches for the earth-pushing start position PS that is closest to the work machine 1 from among the earth-pushing start positions PS in the first region R1 where it is determined that the earth-pushing operation can be executed.

[0077] In S280, if the determination in S270 is YES, the temporary start position determination unit 119b determines whether the volume of the earth pushing target at the earth pushing start position PS calculated in S210 is equal to or greater than the temporary maximum volume.

[0078] The provisional maximum volume means the largest volume of the sediment volume of the earth-pushing target at each of the single or multiple provisional start positions that have been previously provisionally set. When the earth-pushing start position PS is provisionally set for the first time, the volume of the earth-pushing target at the initially set earth-pushing start position PS becomes the provisional maximum volume. If the determination in S280 is YES, the operation determination unit 111A proceeds to S290, and if the determination is NO, the operation determination unit 111A proceeds to S320.

[0079] In S290, if the determination in S280 is YES, the temporary start position determination unit 119b determines whether the volume of the earth moving target at the earth moving start position calculated in S210 is equal to the temporary maximum volume. If the determination in S290 is YES, the operation determination unit 111A proceeds to S300, and if the determination is NO, the operation determination unit 111A proceeds to S310.

[0080] In other words, in S280 and S290, if there are multiple earth-pushing start positions PS at the same distance from the work machine 1 among the earth-pushing start positions PS at which it is determined that the earth-pushing operation can be performed in the first region R1, the operation judgment unit 111A searches for the earth-pushing start position PS at the same distance from the work machine 1 that has the largest volume of earth being pushed by the earth-pushing target at the earth-pushing start position PS.

[0081] In S300, if the answer to S290 is YES, the provisional start position determination unit 119b determines whether the volume of the soil pushing target from the soil pushing start position PS to the soil pushing end position PE calculated in S220 is smaller than the volume of the soil pushing target from the provisional start position to the provisional end position.

[0082] The provisional end position refers to the landslide end position PE of one or more provisional start positions that were previously provisionally set. When the landslide start position PS is provisionally set for the first time, the landslide end position PE provisionally set for the initially provisionally set landslide start position PS becomes the provisional end position. If the determination in S300 is YES, the operation determination unit 111A proceeds to S310, and if the determination is NO, the operation determination unit 111A proceeds to S320.

[0083] In other words, in S300, if there are multiple soil pushing start positions PS at which the soil pushing operation in the first region R1 is judged to be executable and the soil volume of the soil pushing target at the soil pushing start position PS is the same, the operation judgment unit 111A searches for the soil pushing start position PS from the soil pushing start position PS to the soil pushing end position PE where the soil volume of the soil pushing target from the soil pushing start position PS to the soil pushing end position PE is the smallest, from among the soil pushing start positions PS at which the soil pushing target has the same soil volume at the soil pushing start position PS.

[0084] If the determination in S270 is NO, if the determination in S290 is NO, or if the determination in S300 is YES, the operation determination unit 111A proceeds to S310. These cases are when there is a soil-pushing start position PS that is closer to the work machine 1 than the provisional minimum distance, when there is a soil-pushing start position PS where the volume of soil that is the soil-pushing target is greater than the provisional maximum volume, or when there is a soil-pushing start position PS where the volume of soil that is the soil-pushing target from the soil-pushing start position PS to the soil-pushing end position PE is less than the volume of soil that is the soil-pushing target from the provisional start position to the provisional end position.

[0085] In S310, the provisional start position determination unit 119b updates the provisional start position to the earth-pushing start position PS that was temporarily set in S200. If the determination in S270 is NO, the provisional start position determination unit 119b updates the provisional minimum distance to the distance from the work machine 1 to the earth-pushing start position PS calculated in S250. If the determination in S290 is NO, the provisional start position determination unit 119b updates the provisional maximum volume to the volume of earth-pushing target at the earth-pushing start position PS calculated in S210. If the determination in S300 is YES, the provisional start position determination unit 119b updates the volume up to the provisional end position to the volume of earth-pushing target from the earth-pushing start position PS to the earth-pushing end position PE calculated in S220.

[0086] That is, in S260, S270, S280, S290, and S300, the operation determination unit 111A searches for the earth-pushing start position PS at which the earth-pushing operation can be performed most efficiently. If a new earth-pushing start position PS at which the earth-pushing operation can be performed more efficiently is discovered, in S310 the operation determination unit 111A updates the information provisionally set to the newly discovered earth-pushing start position PS, the provisional minimum distance, etc.

[0087] In S310, if the provisional start position, provisional minimum distance, provisional maximum volume, and volume of the soil to be pushed from the provisional start position to the provisional end position are updated at least once (including when the provisional start position is provisionally set for the first time), this means that there is a soil pushing start position PS in the first area R1 included in the fourth area R4 that is determined to be capable of pushing soil.

[0088] In S320, the provisional start position determination unit 119b determines whether the determination of whether pushing of earth is possible has been completed for all positions in the first region R1 included in the fourth region R4. If the determination in S320 is YES, the operation determination unit 111A proceeds to S330. If the determination is NO, the operation determination unit 111A proceeds to S200 and provisionally sets a new pushing of earth start position PS.

[0089] In S330, if the determination in S320 is YES, the earth-pushing start position setting unit 120 finally sets the provisional start position set in S310 as the earth-pushing start position PS. If the earth-pushing start position PS has been set, it means that the next operation to be performed is an earth-pushing operation. However, if the provisional start position has not been updated even once in S310, it means that there is no earth-pushing start position PS in the first region R1 included in the fourth region that is determined to be able to perform earth-pushing, so the earth-pushing start position setting unit 120 does not set the earth-pushing start position PS. If the earth-pushing start position PS has not been set, it means that the next operation to be performed is an excavation operation.

[0090] <Effects> In this embodiment, the operation determination unit 111A determines whether or not to perform an earth-pushing operation to move earth from a first region R1, which includes an area that does not overlap with a second region R2, to a second region R2 that is farther away from the work machine 1 than the first region R1, based on the terrain information. If the operation determination unit 111A determines that the earth-pushing operation is executable, the operation planner 90 plans a trajectory of the bucket 10 for the earth-pushing operation, regardless of whether an excavation operation is executable. The automatic operation control unit 91 controls the operation of the bucket 10 so that the earth-pushing operation is performed.

[0091] When the work machine 1 repeatedly performs excavation and dumping operations, if the soil gets too close to the work machine 1, it will be unable to excavate the soil. Furthermore, the soil may get inside the movable range of the bucket 10 of the work machine 1, making it impossible to perform any work on the soil using the bucket 10. It may also become an obstacle to the travel of the work machine 1. Therefore, during automatic excavation and dumping operations, it is desirable to perform an auxiliary operation to prevent the soil from getting inside the movable range. In this embodiment, the soil pushing operation is performed as appropriate, making it possible to process soil that has gotten too close to the work machine 1. In this embodiment, for example, during automatic excavation and dumping operations, it is possible to prevent the soil from getting too close to the vehicle body so that it is impossible for the bucket 10 to move it.

[0092] In this embodiment, the first region R1 is determined based on the trajectory that the bucket 10 can take in the earth-pushing operation, and the second region R2 is determined based on the trajectory that the bucket 10 can take in the excavating operation. Therefore, the first region R1 and the second region R2 can be determined depending on the difference between the trajectory of the bucket 10 in the earth-pushing operation and the trajectory of the bucket 10 in the excavating operation.

[0093] In this embodiment, the operation determination unit 111A searches for a landslide start position in the first region R1 where the volume of the landslide target at the landslide start position PS is equal to or greater than a first threshold value based on the topographical information, and is therefore able to find a landslide start position PS where the volume of the landslide target is large and a landslide operation needs to be performed.

[0094] In this embodiment, the operation judgment unit 111A searches for a landslide start position PS where the volume of the landslide target from the landslide start position PS to the landslide end position PE is less than or equal to the second threshold value based on the terrain information, and can therefore find a landslide start position PS where the volume of the landslide target is such that the landslide operation is possible.

[0095] In this embodiment, the operation determination unit 111A searches for the earth-pushing start position PS that is closest to the work machine 1, among the earth-pushing start positions PS in the first region R1 at which it is determined that the earth-pushing operation can be performed. Therefore, it is possible to find the earth-pushing start position PS that is closest to the work machine 1 and that is most likely to require the earth-pushing operation to be performed.

[0096] In this embodiment, the operation determination unit 111A searches for the earth-pushing start position PS at which the volume of earth-pushing target at the earth-pushing start position PS is the largest among the earth-pushing start positions PS that are the same distance from the work machine 1. Therefore, it is possible to find the earth-pushing start position PS that is closest to the work machine 1, has the largest volume of earth-pushing target, and requires the most earth-pushing operation.

[0097] In this embodiment, the operation determination unit 111A searches for a soil-pushing start position PS that minimizes the soil volume of the soil-pushing target from the soil-pushing start position PS to the soil-pushing end position PE among the soil-pushing start positions PS that have the same soil volume of the soil-pushing target at the soil-pushing start position PS. This makes it possible to find a soil-pushing start position PS that minimizes the soil volume of the soil-pushing target from the soil-pushing start position PS to the soil-pushing end position PE and allows for efficient soil-pushing operation.

[0098] In this embodiment, the operation determination unit 111A determines whether or not an earth-pushing operation can be performed after the series of operations from the excavation operation to the release of soil, for which the operation planning unit 90 has planned the trajectory of the bucket 10, or the earth-pushing operation, has been completed, but before the operation planning unit 90 plans the next trajectory of the bucket 10. Therefore, the earth-pushing operation can be performed appropriately for each earth-pushing operation and excavation operation of the work machine 1.

[0099] In this embodiment, the operation determination unit 111A determines whether or not to perform an earth-pushing operation that pushes earth and sand from the first region R1 to the second region R2 within the third region R3, the operation planning unit 90 plans the trajectory of the bucket 10 for such earth-pushing operation, and the automatic operation control unit 91 controls the operation of the bucket 10 so that such earth-pushing operation is performed. As a result, earth that has gathered close to the work machine 1 can be pushed into the second region R2 where an excavation operation is performed.

[0100] In this embodiment, the operation determination unit 111A determines whether or not to perform an earth-pushing operation that pushes earth and sand from the first area R1 in the fourth area R4 to the second area R2 in the third area R3, the operation planning unit 90 plans the trajectory of the bucket 10 for such earth-pushing operation, and the automatic operation control unit 91 controls the operation of the bucket 10 so that such earth-pushing operation is performed. Therefore, earth that has gathered close to the work machine 1 can be pushed from the first area R1 where the earth-pushing operation is performed to the second area R2 where the excavation operation is performed.

[0101] Second Embodiment A second embodiment of the present invention will be described below with reference to Figures 9, 10, 11 and 12. Only the differences from the first embodiment will be described below.

[0102] <Control device> 9 is a functional block diagram of a control device 40B in the second embodiment. The control device 40B includes an operation determination unit 111B instead of the operation determination unit 111A in the first embodiment. The operation determination unit 111B determines whether to output a warning. If it is determined that a warning should be output, the operation determination unit 111B outputs the warning to the external system 200.

[0103] Fig. 10 is a functional block diagram of the operation determination unit 111B in Fig. 9 according to the second embodiment. The operation determination unit 111B includes a determination unit 119B instead of the determination unit 119A of the first embodiment. The determination unit 119B further includes a warning determination unit 119c.

[0104] In this embodiment, the sediment volume calculation unit 118 calculates the sediment volume of the fifth region, which is an area inside the first region R1, based on the topography information from the current topography acquisition unit 102 and information about the provisionally set sediment pushing start position PS from the provisional sediment pushing start position setting unit 117.

[0105] The warning determination unit 119c determines, based on information from the sediment volume calculation unit 118, whether or not the sediment volume of the fifth region satisfies the condition for outputting a warning to the external system 200. The warning determination unit 119c outputs a warning to the external system 200 when it determines that a warning is necessary.

[0106] <Action decision flow> FIG. 11 is a flowchart of the operation of the control device 40B in the second embodiment. FIG. 12 is a plan view of the earth-pushing operation in the second embodiment. As shown in FIG. 12, the fifth region R5 is an area inside the first region R1, and is an area where earth-pushing operation cannot be performed. As shown in FIG. 11, the processes of S100 to S130 are performed in the same way as in the first embodiment. In S130, the earth-volume calculation unit 118 calculates the earth-volume of the fifth region R5, which is an area inside the first region R1, based on the topography information from the current topography acquisition unit 102.

[0107] In S140, the warning determination unit 119c determines whether the volume of soil in the fifth region R5 calculated in S130 is equal to or greater than the third threshold value. The volume of soil in the fifth region R5 is determined by the volume of soil that exists above the contact surface of the undercarriage 11 of the work machine 1 in the fifth region R5.

[0108] The third threshold value, like the first threshold value, is determined by experiment or simulation. When the work machine 1 performs an excavation operation while proceeding toward the side of the excavation position, it is desirable that the volume of earth and sand near the work machine 1 is smaller than when the work machine 1 performs an excavation operation while proceeding toward the opposite side of the excavation position. This is because when the work machine 1 climbs over the earth and sand near the work machine 1 to move to a position where it will perform the next excavation operation, the posture of the work machine 1 may become unstable to the point where it is difficult to perform an accurate excavation operation.

[0109] Therefore, the third threshold value may be determined based on information included in the task information regarding whether the work machine 1 performs excavation operations while proceeding toward the excavation position, or whether the work machine 1 performs excavation operations while proceeding toward the opposite side of the excavation position.

[0110] If the determination in S140 is YES, the operation determination unit 111B proceeds to S150, and if the determination is NO, the operation determination unit 111B proceeds to S160. In S150, if the determination in S140 is YES, the warning determination unit 119c outputs a warning to the external system 200. If the determination in S150 is NO, the operation is the same as in the first embodiment.

[0111] <Effects> In this embodiment, when the volume of earth and sand in the fifth region R5, which is a region where earth-pushing operation cannot be performed, is equal to or greater than the third threshold value, the operation determination unit 111B outputs a warning to the external system 200 outside the work machine 1. Therefore, it is possible to respond to the earth and sand in the fifth region R5 based on the warning. [Explanation of symbols]

[0112] 1...Work machine 1A...Front work device 1B...Body 1a...Right operating lever 1b...Left operating lever 2...Hydraulic pump 2a, 2b...Hydraulic pump 2aa, 2ba...regulator 3a...Travel hydraulic motor 3b...Travel hydraulic motor 4...Slewing hydraulic motor 5...Boom cylinder 6...Arm cylinder 7...Bucket cylinder 8...Boom 9...Arm 10...Bucket 10b...Back of bucket 11...Undercarriage 12...Upper rotating body 13...Bucket Link 15a, 15b, 15c, 15d, 15e, 15f...Flow control valve 16a, 16b, 16c, 16d, 16e, 16f, 16g, 16h, 16i, 16j, 16k, 16l...Pressure sensors 18...Engine 23a…Right travel lever 23b...Left travel lever 30...Boom angle sensor 31...Arm angle sensor 32...Bucket angle sensor 33...Vehicle body tilt angle sensor 34...Rotation angle sensor 36...Vehicle position detection device 39...Lock valve 40A, 40B...Control device 43b…Position / orientation calculation unit 44...Electromagnetic proportional valve control section 48...Pilot pump 50...Hydraulic drive unit 60...Working device attitude detection device 70...Terrain detection device 70a, 70b...Distance measurement sensors 81...Actuator control section 90...Motion planning section 91...Automatic operation control unit 100...Input section 102…Current terrain acquisition department 111A, 111B...Operation judgment unit 117...Temporary setting of earth-push start position 118...Sediment volume calculation unit 119A, 119B…Judgment section 119a…Sediment volume determination section 119b...Temporary start position determination section 119c...Warning judgment section 120: Earth pushing start position setting section 130...Pump line 140a, 140b, 141a, 141b, 142a, 142b, 143a, 143b, 144a, 144b, 145a, 145b...Pilot line 150a,150b,151a,151b,152a,152b,153a,153b,154a,154b,155a,155b...Pressure receiving part 160...Solenoid proportional valve unit 200...External system 470...Engine controller 490...Engine RPM detector R0: Range of motion R1…first area R2…Second area R3...Third area R4…4th area R5…5th area PS: Starting position of earth pushing PE: End position of earth pushing PSE…Range

Claims

1. A control device for a work machine equipped with a bucket, a current terrain acquisition unit that acquires terrain information around the work machine; an operation determination unit that determines whether or not to perform an earth-pushing operation in which the back surface of the bucket is used to push earth and sand farther away from the work machine, based on the terrain information acquired by the current terrain acquisition unit; and a motion planning unit that plans a trajectory of the bucket based on the determination of the motion determination unit; an automatic operation control unit that operates the bucket based on the trajectory of the bucket planned by the operation planning unit; Equipped with the operation determination unit determines whether or not the earth-pushing operation for moving earth and sand from a first area set around the work machine to a second area that is farther away from the work machine than the first area, based on the terrain information; the operation planning unit plans a trajectory of the bucket in the earth-pushing operation when the operation determination unit determines that the earth-pushing operation is executable; The automatic operation control unit controls the operation of the bucket so as to perform the earth-pushing operation according to the trajectory of the bucket planned by the operation planning unit. A control device for a work machine.

2. The first area is determined based on a trajectory that the bucket can take during the earth-pushing operation, The second area is determined based on a trajectory that the bucket can take during an excavation operation of scooping up earth and sand using the bucket.

2. The control device for a work machine according to claim 1.

3. The operation determination unit Based on the topographical information, a search is made for a landslide start position in the first area where the landslide operation is started, where the landslide volume of the landslide target is equal to or greater than a first threshold value; determining that the earth-pushing operation is executable when there is a land-pushing start position where the volume of the earth-pushing target at the land-pushing start position is equal to or greater than a first threshold value; 3. The control device for a work machine according to claim 2.

4. The operation determination unit Based on the topographical information, a search is made for a landslide start position where the volume of the landslide target from the landslide start position to a landslide end position, which is a position where the landslide operation ends, is equal to or less than a second threshold value; The method determines that the earth-pushing operation can be performed when there exists a land-pushing start position where the volume of earth-pushing target at the land-pushing start position is equal to or greater than a first threshold value, and there exists a land-pushing start position where the volume of earth-pushing target from the land-pushing start position to the land-pushing end position is equal to or less than a second threshold value.

4. The control device for a work machine according to claim 3.

5. 5. The control device for a work machine according to claim 4, wherein the operation determination unit searches for the earth-pushing start position that is closest in distance from the work machine among the earth-pushing start positions at which it is determined that the earth-pushing operation can be performed.

6. 6. A work machine control device according to claim 5, wherein, when there are multiple earth-pushing start positions that are the same distance from the work machine among the earth-pushing start positions at which it is determined that the earth-pushing operation can be performed, the operation determination unit searches for the earth-pushing start position that has the largest volume of earth being pushed by the earth-pushing target at the earth-pushing start position from among the earth-pushing start positions that are the same distance from the work machine.

7. 5. The control device for a work machine according to claim 4, wherein, when there are multiple earthpushing start positions at which it is determined that the earthpushing operation can be performed and the multiple earthpushing start positions have the same volume of soil of the earthpushing target at the earthpushing start position, the operation determination unit searches for the earthpushing start position at which the volume of soil of the earthpushing target from the earthpushing start position to the earthpushing end position is the smallest from among the earthpushing start positions at which the volume of soil of the earthpushing target at the earthpushing start position is the same.

8. the motion planning unit plans a trajectory of the bucket in an excavation motion of scooping up earth and sand using the bucket; 2. The control device for a work machine according to claim 1, wherein the operation determination unit determines whether the earth-pushing operation can be performed after the excavation operation or the earth-pushing operation for which the operation planning unit has planned the trajectory of the bucket has been completed and before the operation planning unit plans the next trajectory of the bucket.

9. Task information is input to the control device, the task information includes information on the position and size of a third area, which is an area in which an excavation operation of scooping up earth and sand using the bucket is performed and which includes a part of the second area; the operation determination unit determines whether the earth-pushing operation of pushing earth and sand from the first area to the second area within the third area can be performed; when the operation determination unit determines that the earth-pushing operation of pushing earth and sand from the first area to the second area in the third area can be performed, the operation planning unit plans a trajectory of the bucket in the earth-pushing operation of pushing earth and sand from the first area to the second area in the third area; the automatic operation control unit operates the bucket to perform the earth-pushing operation of pushing earth and sand from the first area to the second area within the third area according to the trajectory of the bucket planned by the operation planning unit.

2. The control device for a work machine according to claim 1.

10. The task information includes information on the position and size of a fourth area, which is an area where the earth-pushing operation is performed and includes a part of the first area; the operation determination unit determines whether the earth-pushing operation of pushing earth from the first area in the fourth area to the second area in the third area is executable; when the operation determination unit determines that the earth-pushing operation of pushing earth and sand from the first area within the fourth area to the second area within the third area can be performed, the operation planning unit plans a trajectory of the bucket in the earth-pushing operation of pushing earth and sand from the first area within the fourth area to the second area within the third area; the automatic operation control unit operates the bucket to perform the earth-pushing operation of pushing earth and sand from the first area in the fourth area to the second area in the third area according to the trajectory of the bucket planned by the operation planning unit. The control device for a work machine according to claim 9.

11. 11. The control device for a work machine according to claim 10, wherein the operation determination unit outputs a warning to an external system outside the work machine when the volume of earth and sand in a fifth area, which is an area inside the first area and in which the earth-pushing operation cannot be performed, is equal to or greater than the third threshold value.

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