Route creation device for work machine and work machine

Abstract

To provide a route creation device for a work machine and the work machine capable of optimizing an excavation route correspondingly to geographic changes during excavation even after creating an excavation route to start excavation motion.SOLUTION: A route creation device for a work machine performs: detecting a large rock with large volume and the like potentially affecting an excavation amount in front of a vehicle with an imaging device 12 before starting or before excavation (heavy object detection section 23); measuring topographical information and creating an excavation route where a target excavation amount is allowed to be excavated (route creation section 21); defining a detecting area as an excavation affected area at any height right above an excavation surface of an excavation objective area on the basis of the excavation route (detecting area creating section 22); when detecting intrusion or discharge of specific volume or more rocks and the like in the defined detecting area while excavating along the created excavation route (the heavy object detection section 23), recreating the excavation route such that the excavation amount becomes the target excavation amount (volume change detection section 24→the route creation section 21) to stabilize the excavation amount.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a path generation device for a work machine equipped with a work implement that performs excavation work, and to the work machine. [Background technology]

[0002] Excavating machines, such as hydraulic excavators, are used for purposes such as road and building construction and mineral resource mining. When used in resource mining, which involves excavating natural ground or the ground, it is important to perform the excavation work so that the planned amount of excavation is achieved. For example, unplanned work or events, such as overloading a dump truck with resources, which requires reloading, or underloading a dump truck, which reduces the amount of resources extracted, can contribute to a decrease in the amount of resources extracted.

[0003] Various technologies have been developed for stably excavating an appropriate amount of resources. For example, Patent Document 1 describes a method for determining an excavation start position and a method for generating an excavation trajectory for excavating a target volume from imaged topographical information. Patent Document 2 describes a system for automatically excavating at any excavation depth and curvature of the excavation trajectory. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2020-118017 [Patent Document 2] Japanese Patent Publication No. 2020-041354 Summary of the Invention [Problem to be solved by the invention]

[0005] However, Patent Documents 1 and 2 do not disclose how to deal with changes in the topography during excavation when topographical information is measured before excavation to generate an excavation start position and an excavation path.

[0006] In particular, if there are large objects such as rocks around the excavation route, there is a high possibility that the position of the rocks will change due to changes in the terrain during excavation. For example, if a rock enters the range of the excavation route generated before the excavation, the amount of excavation may be excessive. Also, for example, if a rock that was within the range of the excavation route moves out of that range, the amount of excavation may be insufficient. In this way, changes in the terrain during excavation are thought to have a significant impact on the amount of excavation when performing resource mining work.

[0007] The present invention has been made with this in mind, and aims to provide a path generation device for a work machine and a work machine that are capable of optimizing an excavation path in accordance with changes in the terrain during excavation, even after an excavation path has been generated and excavation operations have begun. [Means for solving the problem]

[0008] In order to solve the above problem, the path generation device for a work machine of the present invention is a path generation device for a work machine equipped with a work implement that performs excavation work, and comprises: a path generation unit that generates an excavation path for moving the work implement to excavate a target excavation volume of an object in the excavation target area based on three-dimensional shape information of the excavation target area of ​​the work machine and attitude information and dimensional information of the work implement; an operation amount generation unit that generates an operation amount for controlling the movement of the work implement along the excavation path; a heavy object detection unit that detects the displacement of a heavy object of a predetermined volume or more that is present in the excavation target area when the work implement is moved along the excavation path based on the three-dimensional shape information of the excavation target area to excavate; and a volume change detection unit that generates a regeneration signal for the excavation path to send to the path generation unit when a volume change caused by the displacement of the heavy object is detected in the estimated excavation volume of the object estimated by the path generation unit based on the excavation path, and is characterized in that the path generation unit regenerates the excavation path based on the volume change caused by the displacement of the heavy object when it receives the regeneration signal for the excavation path from the volume change detection unit. [Effects of the Invention]

[0009] According to the present invention, even after generating an excavation path and starting an excavation operation, the excavation path can be optimized in response to changes in the terrain during excavation. Therefore, for example, by preventing underloading, it is possible to provide a stable excavation volume as planned. In addition, by preventing overloading of dump trucks, etc., it is possible to reduce the time required for reloading. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a side view of an excavation machine according to an embodiment of the present invention. [Figure 2] 1 is a block diagram of a route generation device according to an embodiment of the present invention. [Figure 3] FIG. 10 is a perspective view showing a schematic representation of an estimated excavation volume. [Figure 4] FIG. 10 is a perspective view showing a schematic representation of a detection range. [Figure 5] 3 is a flowchart showing an operation flow of the excavating machine according to the embodiment of the present invention. [Figure 6] 3 is a flowchart showing an excavation flow (automatic excavation control method) of the excavating machine according to the embodiment of the present invention. [Figure 7] FIG. 7 is a diagram showing a schematic representation of the posture of the excavator at step S12 in FIG. 6. [Figure 8] FIG. 7 is a diagram showing a schematic representation of the posture of the excavator at the time of step S16 in FIG. 6. [Figure 9] FIG. 7 is a diagram showing a schematic representation of the posture of the excavator at the time of step S20 in FIG. 6. [Figure 10] FIG. 7 is a diagram showing a schematic representation of the posture of the excavator at the time of step S21 in FIG. 6. [Figure 11] FIG. 7 is a diagram showing a schematic representation of the posture of the excavator at step S24 in FIG. 6 (when a heavy object enters the detection range). [Figure 12] FIG. 7 is a diagram showing a schematic representation of the posture of the excavator at step S24 in FIG. 6 (when a heavy object leaves the detection range). DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each drawing, parts having the same function are designated by the same reference numerals, and repeated description may be omitted.

[0012] [Machine configuration] 1 is a side view of an excavation machine 1 according to this embodiment. The configuration of the excavation machine 1 will be described with reference to FIG.

[0013] The excavation machine 1 is a work machine that excavates earth and sand as an excavation target. The excavation machine 1 according to this embodiment is a hydraulic excavator having a backhoe-type front configuration. Hereinafter, the excavation machine 1 will be referred to as a hydraulic excavator.

[0014] More specifically, the hydraulic excavator 1 includes a self-propelled traveling body 2 and a rotating body 3 that is supported by the traveling body 2 and is rotatable relative to the traveling body 2. The hydraulic excavator 1 includes a front attachment 4 that is rotatably supported on the rotating body 3 and serves as a working device for performing excavation work. The front attachment 4 has a multi-joint structure. The front attachment 4 includes a boom 5 rotatably mounted on the rotating body 3, an arm 6 rotatably mounted relative to the boom 5, a bucket 7 rotatably mounted relative to the arm 6, and a bucket link 43 rotatably mounted between the bucket 7 and the arm 6. The bucket 7 has a box-like shape that forms a space inside for storing soil and sand to be excavated.

[0015] The front device 4 also includes a boom cylinder 45 connected to the revolving unit 3 and the boom 5 and changing the rotation angle of the boom 5 relative to the revolving unit 3, an arm cylinder 46 connected to the boom 5 and the arm 6 and changing the rotation angle of the arm 6 relative to the boom 5, and a bucket cylinder 47 connected to the arm 6 and the bucket link 43 and changing the rotation angle of the bucket 7 relative to the arm 6 via the bucket link 43. The boom cylinder 45, arm cylinder 46, and bucket cylinder 47, which are hydraulic actuators, extend and contract with the supply of hydraulic oil, thereby changing the rotation angle of the boom 5 relative to the revolving unit 3, the rotation angle of the arm 6 relative to the boom 5, and the rotation angle of the bucket 7 relative to the arm 6, respectively.

[0016] The hydraulic excavator 1 also includes a boom angle and angular velocity measuring device 8 that measures the rotation angle and angular velocity of the boom 5. The hydraulic excavator 1 also includes an arm angle and angular velocity measuring device 9 that measures the rotation angle and angular velocity of the arm 6. The hydraulic excavator 1 also includes a bucket angle and angular velocity measuring device 10 that measures the rotation angle and angular velocity of the bucket 7.

[0017] For example, boom angle / angular velocity measuring device 8, arm angle / angular velocity measuring device 9, and bucket angle / angular velocity measuring device 10 each include a gyroscope attached to boom 5, arm 6, and bucket 7. Note that although the angle / angular velocity measuring device is assumed to be an IMU (Inertial Measurement Unit) and is described as an angle / angular velocity measuring device, the form is not important as long as it can measure and calculate angle and angular velocity, and it may be a device that directly measures angle / angular velocity such as a potentiometer / gyro device, or a device that performs numerical differentiation / integration calculations on the measured angular velocity, or a combination of these.

[0018] The boom angle / angular velocity measuring device 8, the arm angle / angular velocity measuring device 9, and the bucket angle / angular velocity measuring device 10 constitute a front angle / angular velocity measuring device 44 (Figure 2) that measures the rotation angle and angular velocity of the front equipment 4, which is a work equipment used for excavation work.

[0019] The hydraulic excavator 1 also has an inclination angle measuring device 11 that measures the inclination of the hydraulic excavator 1 from the horizontal direction.

[0020] The hydraulic excavator 1 is equipped with an imaging device 12 that captures images of the area around the hydraulic excavator 1. From the images captured by the imaging device 12, the hydraulic excavator 1 can acquire (detect) topographical information of the area (excavation target area) around the hydraulic excavator 1 that contains earth and sand to be excavated. The imaging device 12 is, for example, a stereo camera, but the type of imaging device is not important as long as it can acquire topographical information of the excavation target area, and it may be a LiDAR or other 3D measurement device, or a combination of these. The imaging device 12 does not necessarily have to be mounted on the hydraulic excavator 1, but may be installed in the work site environment or mounted on another machine. The hydraulic excavator 1 may have multiple imaging devices 12.

[0021] The hydraulic excavator 1 also includes a path generation device 13 that generates control parameters for automatic control of the front device 4 for excavating an object to be excavated, such as earth and sand, based on information from the imaging device 12, the boom angle / angular velocity measurement device 8, the arm angle / angular velocity measurement device 9, and the bucket angle / angular velocity measurement device 10.

[0022] The hydraulic excavator 1 also includes a vehicle body control device 14 that automatically controls the operation of the front device 4 based on the control parameters generated by the path generation device 13.

[0023] More specifically, the path generating device 13 generates a path (excavation path) along which the bucket 7 of the front device 4 moves in order to excavate a target excavation amount (for example, weight). Then, the path generating device 13 calculates the operation amounts of the boom 5, the arm 6, and the bucket 7 for the bucket 7 to move along the movement path (excavation path), and transmits the calculated values ​​to the vehicle body control device 14.

[0024] Furthermore, the path generating device 13 starts its operation when it receives an automatic excavation instruction signal. For example, the automatic excavation instruction signal is generated by operating a switch, button, or the like for controlling automatic excavation. For example, when a switch, button, or the like is turned ON, the automatic excavation instruction signal is output to the path generating device 13.

[0025] The vehicle control device 14 controls the amount of hydraulic oil supplied to the boom cylinder 45, arm cylinder 46, and bucket cylinder 47 based on the operation amounts of the boom 5, arm 6, and bucket 7 received from the path generation device 13, and controls the extension and contraction amounts of the boom cylinder 45, arm cylinder 46, and bucket cylinder, thereby automatically controlling the movement of the bucket 7 along the movement path (excavation path).

[0026] Although the hydraulic excavator 1 according to this embodiment operates in accordance with the operation of an operator seated in the driver's seat, other embodiments are not limited to this. For example, the hydraulic excavator 1 according to other embodiments may operate in response to an operation signal or an automatic excavation instruction signal transmitted by remote control from an operator operating the hydraulic excavator 1 outside the hydraulic excavator 1.

[0027] [Configuration of the route generation device] FIG. 2 is a block diagram of the path generation device according to this embodiment.

[0028] The path generation device 13 includes a common processing unit 15 that calculates posture information of the front device 4 and three-dimensional shape information of the topography of the excavation target area around the hydraulic excavator 1 (hereinafter simply referred to as three-dimensional information, and this three-dimensional information indicates the three-dimensional information of the excavation target area) based on information from the imaging device 12, the boom angle / angular velocity measuring device 8, the arm angle / angular velocity measuring device 9, and the bucket angle / angular velocity measuring device 10 (front angle / angular velocity measuring device 44).

[0029] The common processing unit 15 includes an attitude calculation unit 16 that calculates attitude information of the front device 4 based on information from the boom angle / angular velocity measurement unit 8, the arm angle / angular velocity measurement unit 9, and the bucket angle / angular velocity measurement unit 10 (front angle / angular velocity measurement unit 44). The common processing unit 15 includes a shape detection unit 17 that detects topographical information of the area to be excavated based on information from the imaging device 12. The attitude calculation unit 16 calculates the angle of the boom 5 relative to the revolving unit 3 around the joint between the boom 5 and the revolving unit 3 based on information from the boom angle / angular velocity measurement unit 8. The attitude calculation unit 16 calculates the angle of the arm 6 relative to the boom 5 around the joint between the boom 5 and the arm 6 based on information from the boom angle / angular velocity measurement unit 8 and the arm angle / angular velocity measurement unit 9. The attitude calculation unit 16 calculates the angle of the bucket 7 relative to the arm 6 around the joint between the arm 6 and the bucket 7 based on information from the boom angle / angular velocity measurement unit 8, the arm angle / angular velocity measurement unit 9, and the bucket angle / angular velocity measurement unit 10. The posture calculation unit 16 calculates three-dimensional position information of each joint and the tip of the bucket 7, etc., as posture information of the front device 4, from the angle information and dimensional information of the front device 4. The shape detection unit 17 generates and updates the three-dimensional information based on information from the imaging device 12.

[0030] The common processing unit 15 is equipped with a coordinate conversion unit 18 that converts the attitude information calculated by the attitude calculation unit 16 and the three-dimensional coordinate information calculated by the shape detection unit 17 into the same coordinate system. The origin of the coordinate system is the intersection of the contact surface of the running unit 2 with the ground and the rotation center line of the rotating unit 3. In the coordinate system, the forward direction of the running unit 2 is set as the positive direction for the x-axis. The direction perpendicular to the ground is set as the positive direction for the z-axis. The direction of the y-axis is set as the positive direction when the x-axis is rotated 90° clockwise around the z-axis. The coordinate conversion unit 18 transmits the attitude information and three-dimensional information (i.e., information regarding the relative position of the front equipment 4 with respect to the excavation work area) that have been converted into the same coordinate system to the path planning unit 20.

[0031] The common processing unit 15 includes an object information acquisition unit 19 that receives density information of excavation objects. For example, the density information may be input by an operator. For example, the density information may be transmitted from another device and received by the object information acquisition unit 19. The object information acquisition unit 19 transmits the received density information to the path planning unit 20.

[0032] The path generation device 13 includes a path planning unit 20 that generates an excavation path before the start of automatic excavation. The path planning unit 20 generates an excavation path when it receives a predetermined automatic excavation instruction signal. In the case of human operation (on-board or remote), the automatic excavation instruction signal is a signal such as a switch or button other than a lever operation signal. In the case of automatic / autonomous control, it is when some kind of automatic excavation instruction signal is received.

[0033] The path planning unit 20 includes a path generation unit 21 that generates an excavation path capable of excavating a target excavation volume. The path generation unit 21 generates an excavation path capable of excavating a target excavation volume based on three-dimensional information and the width dimension information and posture information of the bucket 7. The excavation path can be expressed as a curve function, and various excavation paths can be generated by changing the coefficient parameters of the curve function. The excavation path is determined by optimizing the coefficient parameters of the curve function so that the difference between the estimated excavation volume and the target excavation volume is within a tolerance. The estimated excavation volume is the volume enclosed by the excavation surface and a surface created by extending the excavation path in both lateral directions of the hydraulic excavator 1 from the center of both sides of the bucket 7 to the side of the bucket 7 (see Figure 3). The excavation path is composed of the excavation start point, the excavation end point, and a set of points between them. The excavation path is generated within the range in which the toe of the bucket 7 can operate. The target excavation volume is set for each excavation. The target excavation volume may be set as a constant value in advance, or a value transmitted from another device may be used. The target excavation volume can be set from the density and the target excavation weight, assuming that the density of the excavation target is known (transmitted from the target information acquisition unit 19).

[0034] The path planning unit 20 includes a detection range generation unit 22 that generates a range (detection range) for detecting an increase or decrease in the excavation volume estimated by the path generation unit 21 (in other words, an effect on the estimated excavation volume) due to the entry or exit of a heavy object. The detection range generation unit 22 generates the detection range based on the excavation path generated by the path generation unit 21, the three-dimensional information, and the width dimension information and attitude information of the bucket 7. The detection range generation unit 22 sets the detection range as a range extended by a predetermined dimension (for example, 2 m) in the vertical direction of the excavation surface from an excavation surface that is closed by a surface that can be created by extending from the excavation path in both lateral directions of the hydraulic excavator 1 by the length from the center plane of both sides of the bucket 7 to the side of the bucket 7 (see FIG. 4).

[0035] The path planning unit 20 also includes a heavy object detection unit 23 that detects heavy objects and transmits the detection information to the volume change detection unit 24. The detected heavy objects are objects that exist in the excavation target area and have a volume equal to or greater than a predetermined volume, which affects the estimated excavation volume, for example, a heavy object with a volume equal to or greater than one-tenth of the bucket capacity. The volume of the detected object may be estimated from the maximum width of the detected object. The detection information includes the volume and three-dimensional position information of the heavy object. The object is detected using an object determination device that uses machine learning, which inputs the image and three-dimensional information from the imaging device 12 and outputs the three-dimensional position information of the object. The three-dimensional position information of the detected object is a point cloud of the object's surface. Assuming that the detected object does not have any cavities inside, the volume of the object is calculated from the point cloud of the object's surface. The heavy object detection unit 23 determines (tracks) whether the heavy object detected by the heavy object detection unit 23 is within or outside the detection range generated by the detection range generation unit 22, or more specifically, whether the heavy object has displaced and entered or exited the detection range, and adds information about whether the heavy object is within or outside the detection range to the heavy object.

[0036] The path planning unit 20 regenerates the excavation path when a difference occurs between the estimated excavation volume and the target excavation volume during excavation. To this end, the path planning unit 20 includes a volume change detection unit 24 that determines (detects) a change in the estimated excavation volume. The volume change detection unit 24 detects a volume change in the estimated excavation volume caused by the displacement of the heavy object causing the heavy object to enter or exit the detection range, and generates an excavation path regeneration signal. The volume change detection unit 24 determines that a volume change requiring excavation path regeneration occurs, for example, when an increase or decrease (deviation) occurs between the estimated excavation volume at the time of excavation path generation and the target excavation volume exceeds 10% (tolerance value). Furthermore, the volume change detection unit 24 generates an excavation path switching signal when a volume change state requiring excavation path regeneration continues for a predetermined time (e.g., 1 second) or more. The volume change detection unit 24 adds the volume of the heavy object to the estimated excavation volume, for example, when 60% or more of the volume of the heavy object enters or leaves the detection range. The volume change detection unit 24 transmits the generated regeneration signal, the excavation path switching signal, and the calculated estimated excavation volume to the path generation unit 21.

[0037] When the path generation unit 21 receives an excavation path switching signal from the volume change detection unit 24, it switches the excavation path from the current path to a regenerated path (explained later). There is a discrepancy between the time when the hydraulic excavator 1 generates an operation signal and the time when the signal is reflected in actual operation. Therefore, the path generation unit 21 switches the excavation path so that the excavation path changes between the current excavation path and the regenerated excavation path (explained later) from a point several steps ahead from the point where the excavation path switching signal was received. The volume change detection unit 24 determines, from the posture information, how far along the excavation path the toe of the bucket 7 has moved during excavation. During excavation, the volume change detection unit 24 estimates the estimated excavation volume currently inside the bucket 7 according to the position of the toe of the bucket 7 on the excavation path.

[0038] When the path generation unit 21 receives a regeneration signal from the volume change detection unit 24, it regenerates the excavation path. The path generation unit 21 calculates a corrected target excavation volume from the difference between the initial target excavation volume and the estimated excavation volume received from the volume change detection unit 24. The path generation unit 21 regenerates the excavation path based on the corrected target excavation volume. When a heavy object enters the detection range (the estimated excavation volume increases), the path generation unit 21 generates an excavation path that is shallower from the excavation surface in order to reduce the excavation volume compared to the original excavation path. When a heavy object leaves the detection range (the estimated excavation volume decreases), the path generation unit 21 generates an excavation path that is deeper from the excavation surface in order to increase the excavation volume compared to the original excavation path.

[0039] When the excavation path is regenerated by the path generation unit 21, the detection range generation unit 22 regenerates the detection range based on the excavation path regenerated by the path generation unit 21, the three-dimensional information, the dimensional information up to the width of the bucket 7, and the posture information.

[0040] The path generation device 13 includes an operation amount generation unit 25 that generates an operation amount for controlling the movement of the toe of the bucket 7 along the excavation path generated by (the path generation unit 21 of) the path planning unit 20. The operation amount generation unit 25 generates an operation amount for moving the toe of the bucket 7 along the excavation path from the excavation start position to the excavation completion position. If the position of the toe of the bucket 7 is not near the excavation start position before excavation starts, the operation amount generation unit 25 generates an operation amount for moving the toe of the bucket 7 to the excavation start point of the excavation path.

[0041] [Operation] 5 is a flowchart showing the excavation and loading operation flow of the excavation machine according to this embodiment. The excavation and loading operation of the excavation machine is made up of the operations of excavation (S1), loading (S2), dumping (S3), and leaching (S4), and this embodiment will describe the operation of excavation (S1).

[0042] FIG. 6 is a flowchart showing the automatic excavation control method for the excavating machine according to this embodiment.

[0043] At the start of excavation operation, the operator presses a predetermined switch or button to send an automatic excavation command signal to the path generation device 13. When the path generation device 13 receives the automatic excavation command signal, automatic control begins (step S11). The shape detection unit 17 detects three-dimensional information of the area to be excavated from the information received from the imaging device 12 (step S12). FIG. 7 is a diagram schematically illustrating the posture of the excavator 1 in step S12. The area 26 in FIG. 7 indicates the detection range (imaging range) of the imaging device 12. The object 27 in FIG. 7 indicates an object detected by the imaging device 12. The operator sets the target excavation volume in the path generation unit 21 (step S13). The path generation unit 21 generates an excavation path 28 from the target excavation volume, the three-dimensional information, and the dimensional information and posture information of the bucket 7 (step S14). The excavation path is composed of an excavation start position (point) 29, an excavation completion position (point) 30, and a set of points between them. The detection range generation unit 22 generates a detection range 31 from the excavation path and the three-dimensional information (step S15). The heavy object detection unit 23 detects heavy objects (32, 33) using an object classifier with a machine learning model based on the image and three-dimensional information acquired from the imaging device 12. The detected heavy objects are recognized as heavy object 32 within the detection range and heavy object 33 outside the detection range (step S16). Figure 8 is a diagram showing a schematic representation of the posture of the excavation machine 1 in step S16 (including steps S13 to S16).

[0044] The attitude calculation unit 16 calculates attitude information of the front device 4 from information from the boom angle / angular velocity measurement device 8, the arm angle / angular velocity measurement device 9, and the bucket angle / angular velocity measurement device 10 (front angle / angular velocity measurement device 44). The operation amount generation unit 25 generates an operation amount for moving the tip of the bucket 7 along the excavation path 28 from the excavation start position 29 to the excavation completion position 30 based on the excavation start position and attitude information, and transmits the operation amount to the vehicle body control device 14. The vehicle body control device 14 moves the tip of the bucket 7 to the excavation start position 29 (step S17). The vehicle body control device 14 controls the front device 4 (tracking control along the excavation path) based on the received operation amount (step S18). The operation amount generation unit 25 compares the current position of the tip of the bucket 7 with the excavation completion position 30 to determine whether excavation is complete (whether the current position of the tip of the bucket 7 has reached the excavation completion position) (step S19). When the operation amount generating unit 25 determines that the position of the toe of the bucket 7 is near the excavation completion position 30, it ends the automatic excavation control (step S20). Fig. 9 is a diagram that schematically shows the posture of the excavation machine 1 in step S20.

[0045] If the position of the toe of the bucket 7 is not near the excavation completion position 30, the volume change detection unit 24 determines whether there has been a change in the estimated excavation volume due to a heavy object entering or leaving the detection range 31 (step S21). If there has been no change in the estimated excavation volume in step S21, the process returns to step S18. FIG. 10 is a diagram schematically illustrating the posture of the excavator 1 when a heavy object 33 outside the detection range enters the detection range 31 from the position of a heavy object 33' outside the detection range. If there has been a change in the estimated excavation volume in step S21, the volume change detection unit 24 estimates the excavation volume 35 currently inside the bucket 7 in accordance with the position 34 of the toe of the bucket 7 on the excavation path 28 (step S22).

[0046] FIG. 11 is a diagram showing a schematic representation of the posture of the excavator 1 in step S24 (including steps S23 and S24) when a heavy object enters the detection range 31 and the estimated excavation volume increases. The path generation unit 21 regenerates an excavation path 36 from the current estimated excavation volume 35, the estimated excavation volume at the time of generating the excavation path, the 3D information, and the posture information (step S23). The regenerated excavation path 36 is composed of a start position (point) 34, a completion position (point) 38, and the points between them. Point 34 is the point where the deviation between the target excavation volume and the estimated excavation volume exceeds 10% (the tolerance value) for one second or more. Point 37 indicates the point several steps ahead from point 34 where the excavation path actually changes (switches). The detection range generation unit 22 regenerates a detection range 39 from the regenerated excavation path 36 and the 3D information (step S24). After regenerating the detection range 39, the process returns to step S18.

[0047] FIG. 12 is a diagram showing a schematic representation of the posture of the excavator 1 in step S24 (including steps S23 and S24) when a heavy object within the detection range 31 moves out of the detection range, decreasing the estimated excavation volume. The path generation unit 21 regenerates an excavation path 40 from the current estimated excavation volume 35, the estimated excavation volume at the time of generating the excavation path, the 3D information, and the posture information (step S23). The regenerated excavation path 40 is composed of a start position (point) 34, a completion position (point) 41, and a point cloud between them. Point 34 is the point at which the deviation between the target excavation volume and the estimated excavation volume exceeds 10% (the tolerance value) for one second or more. Point 37 indicates the point several steps ahead from point 34 where the excavation path actually changes (switches). The detection range generation unit 22 regenerates a detection range 42 from the regenerated excavation path 40 and the 3D information (step S24). After regenerating the detection range 42, the process returns to step S18.

[0048] As described above, the path generation device 13 of this embodiment is a path generation device 13 for a work machine (hydraulic excavator 1) equipped with a work implement (front implement 4) for performing excavation work, and includes a path generation unit 21 that generates an excavation path for moving the work implement to excavate an object in the excavation target area by a target excavation volume, based on three-dimensional shape information of the excavation target area of ​​the work machine and attitude information and dimensional information of the work implement; an operation amount generation unit 25 that generates an operation amount for controlling the work implement to move along the excavation path; and a control unit 26 that excavates by moving the work implement along the excavation path, based on the three-dimensional shape information of the excavation target area. The excavation path generating unit 21 includes a heavy object detection unit 23 that detects (tracks) the displacement of a heavy object of a predetermined volume or more (for example, one-tenth or more of the bucket capacity) that exists in the excavation target area when the heavy object is being excavated, and a volume change detection unit 24 that generates a regeneration signal for the excavation path to send to the path generating unit 21 when a volume change caused by the displacement of the heavy object is detected in the estimated excavation volume of the object estimated by the path generating unit 21 based on the excavation path, and when the path generating unit 21 receives the regeneration signal for the excavation path from the volume change detection unit 24, it regenerates the excavation path based on the volume change caused by the displacement of the heavy object.

[0049] The path generation device 13 is equipped with a detection range generation unit 22 that generates a detection range that affects the estimated excavation volume when the heavy object enters or exits, based on the excavation path and three-dimensional shape information of the excavation area and posture information and dimensional information of the work device, and the heavy object detection unit 23 detects the entry or exit of the heavy object into the detection range (due to the displacement of the heavy object), and the volume change detection unit 24 detects the volume change in the estimated excavation volume that occurs when the heavy object enters or exits the detection range (due to the displacement of the heavy object).

[0050] In the path generation device 13, the detection range generation unit 22 sets the detection range to a range extended by a predetermined dimension (e.g., 2 m) in the vertical direction of the excavation surface of the excavation target area relative to the excavation path (see Figure 3).

[0051] In the path generation device 13, when the estimated excavation volume deviates from the target excavation volume by more than a predetermined allowable volume (for example, 10% of the target excavation volume), the volume change detection unit 24 determines that this is a volume change that requires the generation of a regeneration signal for the excavation path.

[0052] In addition, the work device of this embodiment is equipped with the path generation device 13 of the work machine and a vehicle control device 14 that automatically controls the operation of the work device (front device 4) along the excavation path based on the operation amount generated by the operation amount generation unit 25.

[0053] That is, the path generation device 13 of this embodiment uses the imaging device 12 to detect large rocks or other objects that may affect the excavation volume in front of the vehicle before and during excavation (heavy object detection unit 23). It measures topographical information and generates an excavation path that will allow the desired excavation volume to be excavated (path generation unit 21). Based on the excavation path, it defines a detection range as an excavation-affected area at any height perpendicular to the excavation surface of the excavation target area (detection range generation unit 22). While excavating along the generated excavation path, if it detects that a rock or other object of a certain volume or more has entered or been ejected from the defined detection range (heavy object detection unit 23), it regenerates the excavation path (volume change detection unit 24 → path generation unit 21) so that the excavation volume becomes the desired value, thereby stabilizing the excavation volume.

[0054] According to this embodiment, even after generating an excavation path and starting an excavation operation, the excavation path can be optimized in response to changes in the terrain during excavation. Therefore, for example, by preventing underloading, it is possible to provide a stable excavation amount as planned. In addition, by preventing overloading of dump trucks, etc., it is possible to reduce the time required for reloading.

[0055] It should be noted that the present invention is not limited to the above-described embodiment and includes various modifications. For example, the above-described embodiment has been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to an embodiment having all of the described configurations.

[0056] For example, in the above embodiment, the case where the excavating machine 1 is a hydraulic excavator having a backhoe-type front configuration has been described. However, the excavating machine 1 may also be a hydraulic excavator having a loader-type front configuration that is mainly used for upward excavation.

[0057] Furthermore, the functions of the controllers of the above-described embodiments may be implemented in hardware, for example, by designing some or all of them as integrated circuits. Alternatively, the functions may be implemented in software, with a processor interpreting and executing a program that implements each function. Information such as the programs, tables, and files that implement each function can be stored in a storage device within the controller, a hard disk, a solid-state drive (SSD), or other storage media, such as an IC card, SD card, or DVD.

[0058] In addition, the control lines and information lines shown are those that are considered necessary for the explanation, and do not necessarily show all the control lines and information lines in the product. In reality, it can be assumed that almost all components are interconnected. [Explanation of symbols]

[0059] 1. Hydraulic excavator (digging machine, work machine) 2. Running body 3 Rotating body 4 Front equipment (work equipment) 5. Boom 6 Arm 7 Buckets 8. Boom angle and angular velocity measuring device 9. Arm angle and angular velocity measurement device 10. Bucket angle and angular velocity measuring device 11 Tilt angle measuring device 12 Imaging device 13 Route Generation Device 14 Vehicle control device 15 Common processing section 16 Posture calculation section 17 Shape detection unit 18 Coordinate conversion section 19 Object information acquisition unit 20 Route Planning Section 21 Route generation unit 22 Detection range generation unit 23 Heavy object detection unit 24 Volume change detection unit 25 Manipulated amount generation section 26 Detection range of the imaging device (imaging range) 27 Objects detected by imaging device 28 Excavation Path 29 Excavation start position 30 Excavation completed position 31 Heavy object detection range 32 Heavy objects within the detection range 33 Heavy objects outside the detection range 34 Toe position when determining digging path regeneration 35 Estimated excavation volume when determining excavation path regeneration 36 Regenerated excavation path (when a heavy object enters the detection range) 37 Location where the excavation path actually changes before and after regeneration 38 Excavation completion position of the regenerated excavation path (when a heavy object enters the detection range) 39 Heavy object detection range after regeneration of excavation path (when heavy object enters detection range) 40 Regenerated excavation path (if heavy object leaves detection range) 41 Excavation completion position of the regenerated excavation path (when the heavy object leaves the detection range) 42 Heavy object detection range after regeneration of excavation path (when heavy object leaves the detection range) 43 Bucket Link 44 Front angle and angular velocity measuring device 45 Boom cylinder 46 Arm cylinder 47 Bucket cylinder

Claims

1. A path generation device for a work machine equipped with a work implement that performs excavation work, a path generating unit that generates an excavation path for moving the work device to excavate an object in the excavation target area by a target excavation volume based on three-dimensional shape information of the excavation target area of ​​the work machine and attitude information and dimensional information of the work device; an operation amount generating unit that generates an operation amount for controlling the movement of the working device along the excavation path; a heavy object detection unit that detects the displacement of a heavy object having a predetermined volume or more that is present in the excavation target area when the work device is moved along the excavation path to excavate based on three-dimensional shape information of the excavation target area; a volume change detection unit that generates a reproduction signal of the excavation path to be transmitted to the path generation unit when a volume change caused by a displacement of the heavy object is detected in the estimated excavation volume of the object estimated by the path generation unit based on the excavation path, A path generation device for a work machine, characterized in that when the path generation unit receives the regeneration signal for the excavation path from the volume change detection unit, it regenerates the excavation path based on the volume change caused by the displacement of the heavy object.

2. The route generation device for a work machine according to claim 1, a detection range generation unit that generates a detection range that affects the estimated excavation volume when the heavy object enters or exits based on three-dimensional shape information of the excavation path and the excavation target area and attitude information and dimensional information of the work device; The heavy object detection unit detects that the heavy object enters or leaves the detection range, A path generation device for a work machine, characterized in that the volume change detection unit detects a volume change in the estimated excavation volume that occurs when the heavy object enters or leaves the detection range.

3. The route generation device for a work machine according to claim 2, A path generation device for a work machine, characterized in that the detection range generation unit sets the detection range to a range extended by a predetermined dimension in a vertical direction of the excavation surface of the excavation target area relative to the excavation path.

4. The route generation device for a work machine according to claim 1, A path generation device for a work machine, characterized in that the volume change detection unit determines that a volume change requires the generation of a regeneration signal for the excavation path when the estimated excavation volume deviates from the target excavation volume by more than a predetermined allowable volume.

5. The path generation device for a work machine according to claim 1; a vehicle control device that automatically controls the operation of the work device along the excavation path based on the operation amount generated by the operation amount generation unit.

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