Automatic operation device and automatic operation method for work machine

Abstract

This automatic operation device comprises: a detection sensor that detects the height of a work target at a work starting position or a value related to the height; and a controller. The controller acquires the height of the work target on the basis of the value detected by the detection sensor and calculates, on the basis of the height, a target movement path of a specific part (SP) of a work device (3) when the work device (3) performs prescribed work. If the calculated target movement path is within a prescribed region, the controller drives the work device such that the specific part moves along the target movement path, and if at least a portion of the target movement path passes outside of the prescribed region, the controller changes a work region R of the work device or changes the target movement path so as to be within the prescribed region.

Description

Automatic Driving Device and Automatic Driving Method for a Working Machine

[0001] The present disclosure relates to an automatic driving device and an automatic driving method for a working machine.

[0002] Conventionally, an automatic driving device for a working machine has been known (see, for example, Patent Document 1). This working machine has a working device including a bucket. The automatic driving device includes a digging depth setting means for setting a target digging depth at a digging position, and a digging depth determination means for determining whether or not the cutting edge height of the bucket at the digging position has reached the target digging depth. The automatic driving device repeatedly executes the digging operation by the digging device at the same digging position until the digging depth determination means determines that the cutting edge height of the bucket is below the target digging depth.

[0003] However, in the automatic driving device of Patent Document 1, since the digging operation is executed by the digging device (working device) until the digging depth determination means determines that the height of the cutting edge of the bucket is below the target digging depth, the height of the cutting edge of the digging bucket may be below the target digging depth. Here, the target digging depth is set to a depth that can avoid contact between the bottom wall of the pit surrounding the earth and sand (the object to be dug) and the bucket, or a depth determined from design requirements when constructing a building foundation or the like. Therefore, the cutting edge (specific part) of the bucket being below the target digging depth is not preferable from the viewpoint of avoiding interference between the bucket and the bottom wall of the pit or from the viewpoint of meeting design requirements. The same applies not only in the depth direction but also in the horizontal direction and the like.

[0004] Japanese Patent Application Laid-Open No. 2001-123479

[0005] An object of the present disclosure is to provide an automatic driving device capable of keeping the movement path of a specific part of a working device within a predetermined area when causing the working device to execute a predetermined operation.

[0006] An automated driving device according to one aspect of the present disclosure is an automated driving device for controlling the automated driving of a work machine having a work device, comprising: a detection unit for detecting the height of a work object or a value related to said height at a work start position; and a controller for executing a predetermined control process, wherein the predetermined control process includes: the controller obtaining the height of the work object based on the value detected by the detection unit; calculating a target movement path of a specific part of the work device when the work device performs a predetermined work based on said height; and, if the calculated target movement path falls within a predetermined area, executing a normal control process to drive the work device so that the specific part moves along the target movement path; on the other hand, if at least a part of the target movement path passes outside the predetermined area, executing a change control process including a first process for changing the work area of ​​the work device or a second process for changing the target movement path so that it falls within the predetermined area and causing the work device to perform the predetermined work.

[0007] An automated driving method relating to another aspect of the present disclosure is an automated driving method for a work machine that sequentially performs a predetermined work by the work device for each of a plurality of work areas, comprising: a recognition step in which, when the controller performs the change control process while the work device of the work machine is performing the predetermined work in each of the plurality of work areas, the controller recognizes that the predetermined work has been completed at the time of completion of the change control process; a determination step in which the controller determines whether the shape of the surface of the work object in the work area recognized in the recognition step as having been completed has changed between the time of completion of the change control process and the present; and, if the determination step determines that the shape of the surface of the work object has changed, the controller performs the predetermined control process again in the work area in which the shape of the surface of the work object has changed.

[0008] Figure 1 is a side view showing a work machine equipped with an automatic driving device according to an embodiment. Figure 2 is a block diagram showing the schematic configuration of the automatic driving device. Figure 3 is an explanatory plan view for illustrating the schematic of the automatic driving operation of the work machine realized by the automatic driving device according to an embodiment. Figure 4A is an explanatory diagram for illustrating the operation parameters stored in the operation parameter storage unit, and shows the excavation start posture. Figure 4B is an explanatory diagram for illustrating the operation parameters stored in the operation parameter storage unit, and shows the excavation completion posture. Figure 5 is a flowchart showing the contents of the automatic driving control performed by the controller. Figure 6 is a schematic diagram showing a state in which a part of the target movement path passes through a region below the lower limit position. Figure 7 is a diagram corresponding to Figure 5 showing Embodiment 2. Figure 8 is an explanatory diagram for illustrating the schematic of the target movement path change process in Embodiment 2. Figure 9 is a schematic diagram showing an application example of the automatic driving device according to another embodiment. Figure 10 is an explanatory plan view for illustrating an example of automatic driving operation realized by the automatic driving device according to another embodiment.

[0009] The embodiments of this disclosure will be described below with reference to the drawings. Note that the following embodiments are merely examples of the embodiments of this disclosure and are not intended to limit the technical scope of this disclosure.

[0010] (Embodiment 1) Figure 1 is a side view showing a work machine 100 equipped with an automatic driving device 101 according to Embodiment 1 of the present disclosure. The work machine 100 shown in Figure 1 is a hydraulic excavator.

[0011] The work machine 100 comprises a lower traveling body 1, an upper rotating body 2 attached to the lower traveling body 1 so as to be able to rotate relative to the lower traveling body 1 around a vertically extending pivot axis Z, and a work device 3 attached to the upper rotating body 2.

[0012] The working device 3 includes a boom 4 rotatably attached to the upper slewing body 2, an arm 5 rotatably attached to the boom 4, and a bucket 6 rotatably attached to the arm 5.

[0013] The work machine 100 further comprises a boom cylinder 7, which is a hydraulic cylinder for rotating the boom 4; an arm cylinder 8, which is a hydraulic cylinder for rotating the arm 5; a bucket cylinder 9, which is a hydraulic cylinder for rotating the bucket 6; and a slewing motor 11, which is a hydraulic motor for slewing the upper slewing body 2.

[0014] The work machine 100 includes a posture detector 130 for detecting the posture of the work device 3 and a LIDAR (Light Detection and Ranging) 120.

[0015] The attitude detector 130 includes a boom sensor 131 for detecting the attitude of the boom 4, an arm sensor 132 for detecting the attitude of the arm 5, and a bucket sensor 133 for detecting the attitude of the bucket 6. The attitude detector 130 may further include a sensor for detecting the attitude of the upper slewing body 2.

[0016] The boom sensor 131 may be a sensor that detects the angle of the boom 4 with respect to the upper slewing body 2 or the angle of the boom 4 with respect to the horizontal plane, or it may be a sensor that detects the extension or retraction state of the boom cylinder 7.

[0017] The arm sensor 132 may be a sensor that detects the angle of the arm 5 with respect to the boom 4 or the angle of the arm 5 with respect to the horizontal plane, or it may be a sensor that detects the extension or retraction state of the arm cylinder 8.

[0018] The bucket sensor 133 may be a sensor that detects the angle of the bucket 6 with respect to the arm 5 or the angle of the bucket 6 with respect to the horizontal plane, or it may be a sensor that detects the extension and retraction state of the bucket cylinder 9. The sensor that detects the posture of the upper slewing body 2 may be a sensor that detects the posture of the upper slewing body 2 with respect to the horizontal plane, or it may be a sensor that detects the slewing angle of the upper slewing body 2 with respect to the lower traveling body 1.

[0019] The LIDAR 120 (an example of a detection unit) detects values ​​related to the height of the object to be measured that are within its measurement range (in this example, point cloud data including three-dimensional coordinate position information). The LIDAR 120 is positioned so that the entire pit 200 is included within the measurement range during the automatic operation of the work machine 100. The LIDAR 120 obtains the distance from the light emission point to a number of reflection points (i.e., each point in the point cloud that defines the surface shape of the object to be measured) by measuring the time from when the laser light is emitted until the reflected light is received, and obtains point cloud data including the coordinate position of each point based on the obtained distance. The LIDAR 120 inputs the obtained point cloud data to the controller 110 (see Figure 2 described later).

[0020] [Outline of Automatic Operation] The work machine 100 is further equipped with an automatic operation device 101. Figure 2 is a block diagram showing the schematic configuration of the automatic operation device 101. The automatic operation device 101 is a device for automatically operating the work machine 100. Figure 3 is an explanatory plan view illustrating the schematic of the automatic operation of the work machine 100 realized by this automatic operation device 101.

[0021] First, the general outline of the automated operation will be explained with reference to Figure 3. In this automated operation, the work machine 100 automatically excavates soil E (an example of the target object) in a pit 200 embedded in the ground G (an example of the installation surface) and discharges the soil to a predetermined discharge position P0. In the following explanation, the front-to-back and left-to-right directions of the pit 200 are defined as shown by the direction axis in Figure 3.

[0022] The pit 200 is formed in the shape of a rectangular box that opens to the top. The pit 200 stores soil E in its internal space. Specifically, the pit 200 has a first side wall 201 and a second side wall 202 that face each other in the front-rear direction, a third side wall 203 and a fourth side wall 204 that face each other in the left-right direction, and a rectangular plate-shaped bottom wall 205.

[0023] The space inside the pit 200 is the area to be excavated by the work machine 100. Multiple (seven in this example) work areas R1 to R7 are set within the excavation area. The multiple work areas R1 to R7 are not physically separated but are virtual areas. The multiple work areas R are arranged in this order from left to right in the pit 200. In the example in Figure 3, the multiple work areas R1 to R7 are lined up without gaps between them, but this is not limited to this arrangement, and they may be adjacent to each other with gaps in between. In the following explanation, the symbol R will be used when it is not necessary to distinguish between the multiple work areas R1 to R7.

[0024] The work machine 100 repeatedly performs basic operations consisting of excavation and soil removal for each of the work areas R1 to R7 until a predetermined excavation completion condition (the condition of step SA5 described later) is met. In this example, the work machine 100 starts excavation from the leftmost work area R1, and moves the work area in which excavation is performed one by one to the right each time the excavation completion condition is met. After the excavation completion condition in the rightmost work area R7 is met, the work machine 100 returns to a predetermined standby posture (for example, the posture in Figure 1) and ends its automatic operation.

[0025] [Details of the Automatic Driving System] Returning to Figure 2, the details of the automatic driving system 101 will be explained. The automatic driving system 101 comprises a controller 110, the LIDAR 120, an attitude detector 130, an input device 140, a work device drive unit 150, and a driving mechanism unit 160. The controller 110 is connected to the LIDAR 120, the attitude detector 130, the input device 140, the work device drive unit 150, and the driving mechanism unit 160 so as to be able to send and receive signals.

[0026] The controller 110 controls the operation of the work machine 100 to enable automatic operation by the work machine 100. The controller 110 includes a computer that includes a processing unit and memory.

[0027] The controller 110 includes a work start position storage unit 111, an operation parameter storage unit 112, a height calculation unit 113, a target path calculation unit 114, and a control command unit 115. Each of the work start position storage unit 111, the operation parameter storage unit 112, the height calculation unit 113, the target path calculation unit 114, and the control command unit 115 is realized by the computer executing a control program stored in memory.

[0028] The work start position storage unit 111 stores the positions of each work start position P1 to P7 and the soil discharge position P0 in advance. In this example, as shown in Figure 3, each work start position P1 to P7 is located in the center in the left-right direction of the rear end of each work area R1 to R7. The soil discharge position P0 is located on the front side of the pit 200. Each work start position P1 to P7 and the soil discharge position P0 are stored as coordinate positions with respect to a predetermined reference position in a plan view, for example. The reference position can be any position of an object fixed to the ground G. As an example of a reference position, the coordinate positions of the vertices of the four corners of the pit 200 in a plan view can be used.

[0029] The operation parameter storage unit 112 stores various operation parameters necessary for the automatic operation of the work device 3. Figures 4A and 4B are explanatory diagrams for explaining these operation parameters. The operation parameters include, for example, the penetration angle θ and penetration amount δ (see Figure 4A) when the bucket tip SP penetrates the soil E at the start of excavation work by the work device 3. The penetration angle θ is the angle at which the bucket tip SP enters the upper surface of the soil E. The penetration amount δ is the distance from the upper surface of the soil E to the bucket tip SP. The operation parameters further include information related to the target completion posture (see Figure 4B), which is the target posture that the work device 3 should take when the excavation work is completed (for example, angle information of the boom 4, arm 5, and bucket 6). In the target completion posture, the bucket 6 is facing diagonally upward and the soil E is held in the bucket 6. The information related to the target completion posture may include, for example, the amount of the bucket 6 pulled in the front-rear direction from the excavation start posture.

[0030] The height calculation unit 113 calculates the height of the upper end of the soil E relative to the ground G at each work start position P1 to P7 based on the three-dimensional point cloud data (point cloud data defining the surface of the soil E, which is the object to be measured, and including three-dimensional coordinate position information) received from the LIDAR 120. The height calculated by the height calculation unit 113 is a positive value if the upper end of the soil E is located above the ground G, and a negative value if it is located below the ground G.

[0031] The target path calculation unit 114 calculates the target movement path T (see Figure 1) of the bucket tip SP when the work device 3 performs excavation work in each work area R1 to R7. As an example, the target path calculation unit 114 calculates the target movement path T based on the height of the upper end position of the soil E at each work start position P1 to P7 calculated by the height calculation unit 113, the penetration angle θ and penetration amount δ stored in the operation parameter storage unit 112, and the target completion posture of the work device 3 stored in the operation parameter storage unit 112.

[0032] The control command unit 115 acquires the minimum excavation depth L of the soil E (an example of a predetermined minimum depth) input from the input device 140. Then, when the control command unit 115 receives an automatic operation start signal from the input device 140, it executes automatic operation control. When executing automatic operation control, the control command unit 115 outputs command signals to the work device drive unit 150 and the travel mechanism unit 160 so that the bucket tip SP does not pass below the position of the minimum excavation depth L from the ground G (a position separated downward by the minimum excavation depth L from the ground G). Specific details of the control content will be described later.

[0033] The input device 140 is configured to allow the operator to input the minimum excavation depth L. Here, the minimum excavation depth L may be, for example, the distance from the ground G to the top surface of the bottom wall 205 of the pit 200. The input device 140 inputs the information of the input minimum excavation depth L to the controller 110. The input device 140 is also configured to allow the operator to input a start command for automatic operation control. When a start command for automatic operation control is input, the input device 140 inputs a start signal to the controller 110 to indicate this. The input device 140 may be mounted on the work machine 100, or it may be installed in a location away from the work machine 100 and configured to communicate with the work machine 100 wirelessly or via wired connection.

[0034] The work device drive unit 150 includes a boom flow regulator for adjusting the flow rate and direction of hydraulic fluid supplied to the boom cylinder 7, an arm flow regulator for adjusting the flow rate and direction of hydraulic fluid supplied to the arm cylinder 8, a bucket flow regulator for adjusting the flow rate and direction of hydraulic fluid supplied to the bucket cylinder 9, and a slewing flow regulator (none of which are shown) for adjusting the flow rate and direction of hydraulic fluid supplied to the slewing motor 11. Each flow regulator includes, for example, a control valve and an electromagnetic proportional valve for adjusting the pilot pressure supplied to the pilot port of the control valve. The work device drive unit 150 drives the electromagnetic proportional valve in response to a command signal input from the control command unit 115.

[0035] The running mechanism 160 includes a pair of left and right crawlers provided on the lower running body 1, a hydraulic drive motor that rotationally drives the pair of crawlers, a hydraulic pump driven by an engine, and a motor flow regulator for adjusting the flow rate and direction of the hydraulic fluid supplied from the hydraulic pump to the hydraulic drive motor. The motor flow regulator includes, for example, a control valve and an electromagnetic proportional valve that adjusts the pilot pressure supplied to the pilot port of the control valve. The running mechanism 160 drives the electromagnetic proportional valve in response to a command signal input from the control command unit 115.

[0036] Next, we will explain the details of the automatic driving control performed by the controller 110 with reference to the flowchart in Figure 5.

[0037] In step SA1, the control command unit 115 inputs command signals to the work device drive unit 150 and the travel mechanism unit 160 in order to position the work machine 100 in front of the work area R (in this example, the leftmost work area R1 in Figure 3) which is scheduled to be excavated first among the multiple work areas R1 to R7, and to ensure that the center position of the bucket 6 in the width direction coincides with the center position of the work area R in the left-right direction (the state in Figure 3).

[0038] In step SA2, the height calculation unit 113 obtains position information of the work start position P in the work area R where excavation is to be performed from the work start position storage unit 111. Then, the height calculation unit 113 calculates (obtains) the height of the upper end position of the soil E at the work start position P based on the point cloud data of the surrounding work machine 100 input from the LIDAR 120.

[0039] In step SA3, the control command unit 115 inputs a command signal to the work device drive unit 150 in order to penetrate the upper end of the soil E located at the work start position P with a penetration angle θ and a penetration amount δ (see Figure 4A).

[0040] In step SA4, the target path calculation unit 114 calculates the target movement path T of the bucket tip SP. The details of the target movement path calculation process are as described above, so an explanation is omitted here.

[0041] In step SA5, the control command unit 115 determines whether at least a portion of the target movement path T passes through an area below a lower position separated from the ground G by the lower excavation limit depth L. Figure 6 is a schematic diagram showing an example of a state in which a portion of the target movement path T passes below the lower limit position LP. If the determination in step SA5 is NO, the process proceeds to step SA8; if YES, the process proceeds to step SA6. The lower excavation limit depth L is a depth set by the operator via the input device 140 as described above, and in this example, it is set to the depth of the upper surface of the bottom wall 205 of the pit 200.

[0042] In step SA6, the control command unit 115 determines whether the work area R where excavation is to be performed is an area other than the work area R (in this example, the work area R7 located on the rightmost side in FIG. 3) that is scheduled to be excavated last. If this determination is NO (that is, when the work area R where excavation is to be performed is the work area R that is scheduled to be excavated last), this automatic driving control is terminated. On the other hand, if this determination is YES, the process proceeds to step SA7.

[0043] In step SA7, the control command unit 115 moves the work machine 100 to the front side of the work area R adjacent to the right side so as to change the work area R where excavation is to be performed to the work area R adjacent to the right side of the current work area R, and then returns to step SA2.

[0044] In step SA8, which proceeds when the determination in step SA5 is NO, the control command unit 115 inputs a command signal to the work device drive unit 150 to cause the work device 3 to perform an excavation operation. Specifically, the control command unit 115 inputs a command signal to the work device drive unit 150 so as to change the work device 3 from the excavation start posture to the excavation completion posture. In other words, the control command unit 115 causes the work device 3 to perform an excavation operation so that the trajectory of the bucket tip SP follows the target movement path T.

[0045] In step SA9, the control command unit 115 inputs a command signal to the work device drive unit 150 to cause the work device 3 to perform a soil discharge operation. Specifically, the control command unit 115 inputs a command signal to the work device drive unit 150 so as to rotate the work device 3 by a predetermined angle around the swivel axis Z from the excavation completion posture to move the bucket 6 to the soil discharge position P0 (see FIG. 3) and rotate the bucket 6 downward at the soil discharge position P0. After the processing of this step SA9 is completed, the process returns to step SA2.

[0046] In the automated driving device 101 configured as described above, when automated driving control is performed by the controller 110, basic operations consisting of excavation work (step SA8) and soil discharge work (step SA9) are repeatedly performed for each of the work areas R1 to R7 until a predetermined excavation completion condition is met. Here, the predetermined excavation completion condition is the condition of step SA5, that is, the condition that the target movement path T of the bucket tip SP calculated by the controller 110 passes below the lower limit position LP, which is located below the height position of the ground G (an example of a predetermined reference height position) by the lower limit depth L of the excavation. When this condition is met, the excavation work and soil discharge work by the work device 3 are not performed, and the work area R in which excavation is performed is changed to a work area R adjacent to the right of the current work area R. Therefore, the excavation path of the bucket tip SP can be contained within a predetermined area located above the lower limit position LP. Thus, interference between the bucket 6 and the bottom wall 205 of the pit 200 located at the lower limit depth L of the excavation can be prevented.

[0047] As described above, in this embodiment, the automatic driving device 101 includes a LIDAR 120 that detects a value related to the height of the soil E at the work start position P, and a controller 110 that executes a predetermined control process. In the predetermined control process, the height of the soil E at the work start position P is obtained based on the value detected by the LIDAR 120 (in this example, the coordinate value of three-dimensional point cloud data), and based on this height, the target movement path T of the bucket tip SP of the work device 3 when the work device 3 performs excavation work is calculated. If the calculated target movement path T falls within a region (predetermined region) above the lower limit position LP, which is the position of the lower limit depth L of the excavation, a normal control process is executed to drive the work device 3 so that the bucket tip SP moves along the target movement path T. On the other hand, if at least a part of the target movement path T passes below the lower limit position LP, a change control process (first process) is executed to change the work area R of the work device 3.

[0048] According to this configuration, when causing the working device 3 to perform excavation work, the movement path of the working device 3 can be contained within a region above the lower limit position LP which is the position of the excavation lower limit depth L. That is, according to the said configuration, when it is predicted that the bucket tip SP of the working device 3 will pass through a region below the lower limit position LP which is the position of the excavation lower limit depth L, the working area R itself by the working device 3 is changed. Therefore, it is avoided that the bucket tip SP of the working device 3 passes through a region below the lower limit position LP. Therefore, it is possible to avoid the excavation work by the working device 3 reaching a depth exceeding the lower limit position LP. Consequently, problems such as the bucket tip SP interfering with the bottom wall 205 and being damaged can be avoided.

[0049] In the said embodiment, the automatic driving device 101 further includes an input device 140 (an example of a setting unit) by which an operator can set the excavation lower limit depth L.

[0050] According to this configuration, since the operator can set the excavation lower limit depth L, various excavation lower limit depths L can be easily set according to the on-site situation.

[0051] (Embodiment 2) Fig. 7 is a diagram corresponding to Fig. 5 showing Embodiment 2. In this embodiment, the content of the automatic driving control executed by the controller 110 is different from that of Embodiment 1.

[0052] The processing of steps SB1 to SB5, SB7 to SB10 in Fig. 7 is the same as steps SA1 to SA5 and SA6 to SA9 of Embodiment 1 respectively, and only the processing of step SB6 is different from that of Embodiment 1. Therefore, hereinafter, only the details of step SB6 will be described, and the description of other processing will be omitted.

[0053] That is, in step SB6, the target path calculation unit 114 changes the target movement path T calculated in step SB4 so that a part thereof follows the lower limit position LP. Then, the control command unit 115 causes the working device 3 to perform excavation work based on this changed target movement path T'. Specifically, the control command unit 115 inputs a command signal to the working device drive unit 150 so that the bucket tip SP moves along the changed target movement path T'.

[0054] Figure 8 is an explanatory diagram illustrating the overview of the process for changing the target movement path T in the target path calculation unit 114. In Figure 8, the dashed line shows the target movement path T before the change, and the dashed line shows the target movement path T' after the change. The target path calculation unit 114 calculates the target movement path T' after the change by replacing the portion of the target movement path T before the change that passes below the lower limit position LP (a position separated from the ground G by the lower limit excavation depth L) with a horizontal straight path along the lower limit position LP. It is preferable that this horizontal straight path is located slightly above the lower limit position LP.

[0055] As described above, the automatic driving device 101 of this embodiment includes a LIDAR 120 that detects a value related to the height of the soil E at the work start position P, and a controller 110 that executes a predetermined control process. In the predetermined control process, the height of the soil E at the work start position P is obtained based on the value detected by the LIDAR 120, and based on this height, the target movement path T of the bucket tip SP of the work device 3 when the work device 3 performs excavation work is calculated. If the calculated target movement path T falls within a region (predetermined region) above the lower limit position LP (a position separated by a minimum excavation depth L below the height position of the ground G), a normal control process is executed to drive the work device 3 so that the bucket tip SP moves along the target movement path T. On the other hand, if at least a part of the target movement path T passes below the lower limit position LP (an example outside the predetermined region), a change control process (second process) is executed to change the target movement path T of the bucket tip SP so that it falls within a region above the lower limit position LP, and to cause the work device 3 to perform excavation work.

[0056] With this configuration, if it is predicted that the bucket tip SP of the work device 3 will pass through an area below the lower limit position LP, the target movement path T of the bucket tip SP is changed so that it falls within an area above the lower limit position LP. Therefore, it is possible to avoid the excavation work by the work device 3 extending to a depth beyond the lower limit position LP. Consequently, problems such as the bucket tip SP interfering with the bottom wall 205 and being damaged can be avoided.

[0057] In this embodiment, the controller 110 replaces the portion of the target movement path T that passes below the lower limit depth L with a path that aligns with the lower limit position LP.

[0058] With this configuration, the excavation depth by the bucket 6 can be secured up to near the lower limit position LP, while the movement path of the bucket tip SP of the work machine 100 can be contained within a region above the lower limit position LP.

[0059] (Other Embodiments) Although an automated driving device 101 according to an embodiment of the present disclosure has been described above, the present disclosure is not limited thereto.

[0060] (1) In Embodiment 2, if the target movement path T passes below the lower limit position LP, the process of step SB6 (the process of changing the target movement path T and performing the excavation operation based on the changed target movement path T') is always executed, but this is not the only option. That is, for example, if it is predicted that a sufficient amount of soil cannot be secured if the excavation operation is performed based on the changed target movement path T', the process of step SB7 and later may be executed without performing the process of step SB6 (by skipping step SB6). Specifically, the controller 110 calculates the area (shaded area in Figure 8) of the portion of the target movement path T located below the lower limit position LP, viewed from the lateral direction (the direction parallel to the swing axis of the bucket 6). The controller 110 then skips the process of step SB6 if the area ratio, which is the value obtained by dividing the calculated area by the area of ​​the inner region of the target movement path T, is equal to or greater than a predetermined ratio, as it is assumed that a sufficient amount of soil cannot be secured by the excavation operation. Furthermore, instead of calculating the area ratio, the volume ratio may be calculated, or the weight ratio may be calculated taking into account the density of the soil, etc. Also, instead of calculating a ratio compared to when such a normal excavation operation is performed, the judgment may be made based on the absolute amount of soil. That is, the controller 110 may skip the processing of step SB6 if the amount of soil captured in the bucket 6 by the excavation operation based on the changed target movement path T' is less than or equal to a predetermined amount. This predetermined amount may be determined by multiplying the average value of each excavation operation up to now by a predetermined ratio.

[0061] (2) In each of the above embodiments, an example was described in which the predetermined operation performed by the work device 3 is excavation work and the work object is soil E. However, the invention is not limited to this, and the predetermined operation may be metal scrap recovery work and the work object may be metal scrap. Figure 9 is a schematic diagram showing an example of metal scrap recovery work. In this example, a magnet 15 is attached to the tip of the arm 5, and the magnet 15 is moved diagonally back and forth along the slope of the pile of metal scrap to attract the metal scrap to the magnet 15, after which the arm 5 is pulled up and moved to the side. In Figure 9, three work areas Q1 to Q3 and work start positions P10 to P12 are set in advance for each of the work areas Q1 to Q3. The controller sets the lower end MP of the magnet 15 as a specific part, and if at least a part of the target movement trajectory of this specific part passes below the lower excavation depth L, it performs a first process to change the work area to Q2 or Q3. Alternatively, the controller may perform a second process instead of the first process, which involves changing the target movement path so that the lower end MP of the magnet 15 is within the area above the lower limit depth L of the excavation, and then driving the work device 3 based on the changed target movement path.

[0062] (3) In each of the above embodiments, the automatic operation control is terminated after the excavation work of the work device 3 is completed in the rightmost work area R7, but this is not limited to this. For example, after the excavation work of the work device 3 is completed in the rightmost work area R7, the work machine 100 is moved to the leftmost work area R1, and during this movement, it is determined whether or not there is a work area R in which the surface shape of the soil E has changed based on the value detected by the LIDAR 120, and if there is, the processing of steps SA2 to SA9 or steps SB2 to SB10 is executed again in the work area R in which the surface shape of the soil E has changed. With this configuration, the following automatic operation method is realized. In other words, the automated driving method includes a recognition step in which, when the controller 110 executes a change control (step SA7 or step SB6) while the work device 3 of the work machine 100 is performing an excavation operation (predetermined operation) in each of the multiple work areas R, the controller recognizes that the predetermined operation has been completed at the time the change control is completed; a determination step in which the controller 110 determines whether the shape of the surface of the soil E (work object) in the work area R in which the excavation operation (predetermined operation) was recognized as completed in the recognition step has changed between the time the change control was completed and the present time; and an execution step in which, if the determination step determines that the shape of the surface of the soil E has changed, the controller 110 executes a predetermined control process (processing of steps SA2 to SA9 or processing of steps SB2 to SB10) in order to have the work device 3 perform an excavation operation again in the work area R in which the shape of the surface of the soil E has changed.

[0063] According to this automated operation method, even in areas of the multiple work areas R where excavation work by the work device 3 has been completed, the controller 110 will re-execute predetermined control processing for work areas R where the surface shape of the soil E has changed thereafter. This ensures that excavation work by the work device 3 is fully and completely performed for each of the multiple work areas R.

[0064] (4) In each of the above embodiments, the detection sensor is composed of a LIDAR 120 that acquires values ​​related to the height of the soil E, which is the work object (point cloud data including 3D coordinate position), but is not limited to this. The detection sensor may be a sensor that detects the height of the soil E, which is the work object, itself. Other examples of detection sensors include, for example, a millimeter-wave radar or a stereo camera.

[0065] (5) In each of the above embodiments, one controller 110 is configured to function as a work start position storage unit 111, an operation parameter storage unit 112, a height calculation unit 113, a target path calculation unit 114, and a control command unit 115, but is not limited to this. For example, a separate controller having the function of the height calculation unit 113 may be provided. That is, the functions of the controller of this disclosure may be realized by one controller or by multiple controllers.

[0066] (6) In each of the embodiments described above, the predetermined region is defined as the region above the lower limit position LP, but it is not limited to this and may include a boundary line along the lower limit position LP. In this case, the straight portion along the lower limit position LP in the modified target movement path T' in Embodiment 2 (see Figure 8) does not necessarily have to be located slightly above the lower limit position LP, and may be located at the same height as the lower limit position LP.

[0067] (7) In each of the above embodiments, in step SA5 or SB5, it is determined whether at least a part of the target movement path T passes below the lower limit position LP, and if this determination is YES, change control consisting of changing the work area R or changing the target movement path T is performed, but it is not limited to this. That is, the determination of whether the target movement path T passes outside the predetermined area is not limited to determining whether it passes outside in the depth direction, but may also include determining whether it passes outside in the front-to-back direction or the left-to-right direction, for example. In other words, any process that performs a determination of whether the target movement path T passes outside the predetermined area is acceptable. Furthermore, the predetermined area does not necessarily have to be a closed space, and its shape, size, or use is not limited in any way.

[0068] (8) In each of the above embodiments, the automatic driving device 101 may be attached to the work machine 100, or it may be installed in a location away from the work machine 100. In the latter case, the automatic driving device 101 may be configured to communicate with the work machine 100, for example, wirelessly or via a wired connection. Alternatively, for example, only the controller 110 of the automatic driving device 101 may be installed in a location away from the work machine 100.

[0069] (9) In each of the above embodiments, the lower limit position LP is set at a position separated by a predetermined lower limit depth from the height position (an example of a predetermined reference height position) of the installation surface (ground G) of the work machine 100, but is not limited to this. For example, if the work machine 100 performs excavation work at a position higher than its installation surface, the predetermined reference height position will be located above the installation surface of the work machine 100. As an example, the pit 200 may be positioned so as to protrude above the ground G. In this case, the upper end position of the pit 200 can be set as the predetermined reference height position. Alternatively, the predetermined reference height position may be lower than the installation surface of the work machine 100. As an example, the pit 200 may be embedded in the ground which is lower than the installation surface of the work machine 100 (for example, a surface one level lower than the ground G). In this case, the height position of the ground which is lower than the installation surface can be set as the predetermined reference height position.

[0070] (10) In each of the embodiments described above, the predetermined region is defined as the region between the reference height position (for example, the height position of the ground G) and the lower limit position LP (the boundary may or may not be included), but is not limited to this. In order to demarcate the predetermined region, (i) an upper limit position (not shown) located above the reference height position may be set instead of the lower limit position LP, or (ii) the upper limit position (not shown) may be set in addition to the lower limit position LP. In the former case (i), the predetermined region is defined as the region between the reference height position and the upper limit position (the boundary may or may not be included), and in the latter case (ii), the predetermined region is defined as the region between the lower limit position LP and the upper limit position (the boundary may or may not be included). The upper limit position may be set, for example, at the height of the lower surface of a ceiling wall if a ceiling wall exists above the reference height position. Alternatively, the upper limit position may be set as a design upper limit height position set from a safety standpoint (a height position set virtually, not a height position restricted by an actual existing object).

[0071] (11) The scope of the present disclosure includes any combination of the embodiments described above. For example, the control process of Embodiment 1 and the control process of Embodiment 2 may be combined. In this case, an operating unit (for example, a changeover switch that can be operated by an operator) for switching between the control process of Embodiment 1 and the control process of Embodiment 2 may be provided.

[0072] The specific embodiments described above mainly include the following configurations.

[0073] (1) An automatic driving device relating to one aspect of the present disclosure is an automatic driving device for controlling the automatic driving of a work machine having a work device, comprising: a detection unit for detecting the height of a work object or a value related to said height at a work start position; and a controller for executing a predetermined control process, wherein the predetermined control process includes: the controller obtaining the height of the work object based on the value detected by the detection unit; calculating a target movement path of a specific part of the work device when the work device performs a predetermined work based on said height; and, if the calculated target movement path falls within a predetermined area, executing a normal control process to drive the work device so that the specific part moves along the target movement path; on the other hand, if at least a part of the target movement path passes outside the predetermined area, executing a change control process including a first process for changing the work area of ​​the work device or a second process for changing the target movement path so that it falls within the predetermined area and causing the work device to perform the predetermined work.

[0074] This configuration allows the movement path of a work device to be contained within a predetermined area when the work device is made to perform a predetermined task. In other words, with this configuration, if at least a part of the target movement path passes outside the predetermined area, either a first process that changes the work area of ​​the work device or a second process that changes the target movement path to be contained within the predetermined area is executed. In the first process, if it is predicted that a specific part of the work device will pass outside the predetermined area (i.e., the target movement path will pass outside the predetermined area), the work area of ​​the work device itself is changed. In the second process, if it is predicted that a specific part of the work device will pass outside the predetermined area (i.e., the target movement path will pass outside the predetermined area), the target movement path of the specific part of the work device is changed to be contained within the predetermined area. In either process, it is avoided that a specific part of the work device will pass outside the predetermined area.

[0075] (2) In the automatic driving device described in (1) above, the predetermined operation is an excavation operation, the predetermined area is an area above a lower limit position that is separated from a predetermined reference height position by a predetermined lower limit depth, and in the predetermined control processing, if the calculated target movement path falls within the predetermined area, the normal control processing is executed, while if at least a part of the calculated target movement path passes below the predetermined area, the modification control processing is executed.

[0076] With this configuration, when the work device performs excavation work, if the target movement path of a specific part of the work device passes below a predetermined area, the change control is executed, thereby preventing the excavation work by the work device from extending to a depth exceeding the lower limit position (lower limit depth position). The predetermined reference height position is set, for example, at the height of the installation surface of the work machine, but is not limited to this.

[0077] (3) In the automatic operation device described in (2) above, it is preferable that the device further includes a setting unit that allows the operator to set the predetermined lower limit depth.

[0078] With this configuration, the worker can set the minimum depth, making it easy to set various minimum depths according to the site conditions.

[0079] (4) In the automatic driving device of (2) or (3) above, the second process is preferably a process in which the portion of the calculated target movement path that passes below the predetermined area is replaced with a path along the lower limit position, thereby changing the target movement path so that it fits within the predetermined area, and causing the work device to perform the predetermined work based on the changed target movement path.

[0080] With this configuration, by replacing the portion of the target movement path that passes below the predetermined area with a path along the lower limit position, it is possible to keep the movement path of a specific part of the work machine within the predetermined area while ensuring an excavation depth close to the lower limit depth.

[0081] (5) An automated driving method relating to another aspect of the present disclosure is an automated driving method for a work machine that sequentially performs the predetermined work by the work device for each of a plurality of work areas, comprising: a recognition step in which, when the controller performs the change control process while the work device of the work machine is performing the predetermined work in each of the plurality of work areas, the controller recognizes that the predetermined work has been completed at the time of completion of the change control process; a determination step in which the controller determines whether the shape of the surface of the work object in the work area in which the predetermined work was recognized as completed in the recognition step has changed between the time of completion of the change control process and the present; and an execution step in which, if the determination step determines that the shape of the surface of the work object has changed, the controller performs the predetermined control process again in the work area in which the shape of the surface of the work object has changed.

[0082] According to this automated driving method, even in areas where predetermined work has been completed by the work device among multiple work areas, the controller will re-execute predetermined control processing for work areas where the surface shape of the work object has changed, thereby ensuring that predetermined work by the work device is completed without any omissions in each of the multiple work areas. An example of a change in the surface shape of the work object is when excavation work is performed as a predetermined work, and surrounding soil collapses and enters the work area where the excavation work has been completed. The recognition step may be performed by the controller or by a person (operator). Similarly, the determination step may be performed by the controller or by a person (operator). When the determination step is performed by the controller, it is sufficient to determine whether or not the surface shape of the work object has changed based on the detected value from the detection sensor.

Claims

1. An automatic driving device for controlling the automatic operation of a work machine having a work device, comprising: a detection unit for detecting the height of a work object or a value related to said height at the work start position; and a controller for executing a predetermined control process, wherein the predetermined control process includes: the controller obtaining the height of the work object based on the value detected by the detection unit, calculating a target movement path of a specific part of the work device when the work device performs a predetermined work based on said height, and executing a normal control process to drive the work device so that the specific part moves along the target movement path if the calculated target movement path falls within a predetermined area, while executing a change control process including a first process for changing the work area of ​​the work device or a second process for changing the target movement path so that it falls within the predetermined area and causing the work device to perform the predetermined work, if at least a part of the target movement path passes outside the predetermined area.

2. An automatic driving device according to claim 1, wherein the predetermined operation is an excavation operation, the predetermined region is a region above a lower limit position separated by a predetermined lower limit depth from a predetermined reference height position, and in the predetermined control process, if the calculated target movement path falls within the predetermined region, the normal control process is executed, while if at least a part of the calculated target movement path passes below the predetermined region, the modified control process is executed.

3. An automatic driving device according to claim 2, further comprising a setting unit that allows an operator to set the predetermined lower limit depth.

4. An automatic driving device according to claim 2 or 3, wherein the second process is a process of changing the target movement path so that it fits within the predetermined area by replacing the portion of the calculated target movement path that passes below the predetermined area with a path along the lower limit position, and causing the work device to perform the predetermined work based on the changed target movement path.

5. An automatic operation method for a work machine, wherein the work machine sequentially performs a predetermined operation on each of a plurality of work areas using the automatic operation device described in claim 1, the method comprising: a recognition step in which, when the controller executes the change control process while the work machine's work device is performing the predetermined operation on each of the plurality of work areas, the controller recognizes that the predetermined operation has been completed at the time of completion of the change control process; a determination step in which the controller determines whether the shape of the surface of the work object in the work area recognized in the recognition step as having completed the predetermined operation has changed between the time of completion of the change control process and the present time; and, if the determination step determines that the shape of the surface of the work object has changed, the controller executes the predetermined control process to cause the work device to perform the predetermined operation again in the work area where the shape of the surface of the work object has changed.

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