Control System and Control Method

Abstract

To provide an automatic exhaust soil control system suppressed in lowering of a lowest point of a bucket.SOLUTION: An automatic control determining part determines whether or not to start automatic exhaust soil control. An exhaust soil control part, when determining to start the automatic exhaust soil control, forms a first command to rotate a bucket in the exhaust soil direction, until an inclination of the bucket becomes a prescribed exhaust soil completion angle. The exhaust soil control part forms a second command for rotating a boom in a rising direction, while the bucket inclination becomes an exhaust soil completion angle from the inclination of the start of the automatic exhaust soil control to exhaust soil completion angle.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] The present disclosure relates to a control device and a control method for a work system.

Background Art

[0002] Patent Document 1 discloses a technique related to automatic loading control of a working machine. The working machine described in Patent Document 1 automatically performs hoist swing control while preventing the bucket from contacting the transport vehicle, and then discharges the excavated material.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The working machine described in Patent Document 1 discharges the excavated material by rotating the bucket in the soil discharge direction. Generally, since the point farthest from the bucket pin in the outer shell of the bucket is the cutting edge of the bucket, when the bucket is rotated in the soil discharge direction, the lowest point of the bucket drops. Therefore, the working machine described in Patent Document 1 needs to discharge the excavated material from a high position in consideration of the locus of the lowest point due to the rotation of the bucket. On the other hand, the higher the soil discharge position, the higher the possibility that the excavated material spills from the transport vehicle. If there is a lot of spilled excavated material, the scaffold around the target parking position of the transport vehicle will be damaged and it will be difficult to stop. An object of the present disclosure is to provide a control system and a control method capable of realizing soil discharge at a low position in automatic soil discharge control.

Means for Solving the Problems

[0005] According to one aspect, a control system is a control device for a work machine including a work machine main body, a boom rotatably attached to the work machine main body, an arm rotatably attached to the tip of the boom, and a bucket rotatably attached to the tip of the arm, the control device including an automatic control determination unit that determines whether to start automatic dumping control, and a bucket control unit that, when it is determined to start the automatic dumping control, generates a first command to rotate the bucket in the dumping direction until the inclination of the bucket reaches a predetermined dumping completion angle, and a boom control unit that, based on the bucket command, generates a second command to rotate the boom in the upward direction while the inclination of the bucket changes from the inclination at the start of the automatic dumping control to the dumping completion angle.

Effect of the Invention

[0006] According to the above aspect, the control system can suppress the lowering of the lowest point of the bucket in automatic dumping control.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

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Figure 8

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Figure 12

[0008] <First Embodiment> <<Working System 1>> FIG. 1 is a schematic diagram showing the configuration of a working system according to the first embodiment. The working system 1 includes a working machine 100, one or more transport vehicles 200, and a control device 300. The working system 1 is an unmanned transport system that automatically controls the working machine 100 and the transport vehicle 200 by the control device 300.

[0009] The transport vehicle 200 travels unmanned based on course data (for example, speed data, coordinates where the transport vehicle 200 should travel) received from the control device 300. The transport vehicle 200 and the control device 300 are connected by communication via an access point 400. The control device 300 acquires the position and orientation from the transport vehicle 200, and generates course data used for the travel of the transport vehicle 200 based on these. The control device 300 transmits the course data to the transport vehicle 200. The transport vehicle 200 travels unmanned based on the received course data. Note that although the working system 1 according to the first embodiment includes an unmanned transport system, in other embodiments, some or all of the transport vehicles 200 may be manned. In this case, the control device 300 does not need to transmit course data and instructions regarding loading, but acquires the position and orientation of the transport vehicle 200.

[0010] The working machine 100 is unmannedly controlled according to instructions received from the control device 300. The working machine 100 and the control device 300 are connected by communication via the access point 400.

[0011] The working machine 100 and the transport vehicle 200 are provided at a work site (for example, a mine, a quarry). On the other hand, the control device 300 may be provided at any location. For example, the control device 300 may be provided at a location away from the working machine 100 and the transport vehicle 200 (for example, in a city, within the work site).

[0012] 《Transport Vehicle 200》 The transport vehicle 200 according to the first embodiment is a dump truck including a vessel 201. Note that the transport vehicle 200 according to other embodiments may be a transport vehicle other than a dump truck. The transport vehicle 200 includes a vessel 201, a position and orientation calculator 210, and a control device 220. The position and orientation calculator 210 calculates the position and orientation of the transport vehicle 200. The position and orientation calculator 210 includes two receivers that receive positioning signals from artificial satellites constituting GNSS (Global Navigation Satellite System). An example of GNSS is GPS (Global Positioning System). The two receivers are installed at different positions of the transport vehicle 200, respectively. The position and orientation calculator 210 detects the position of the transport vehicle 200 in the local coordinate system based on the positioning signals received by the receivers. The position and orientation calculator 210 calculates the orientation of the transport vehicle 200 as the relationship between the installation positions of the two receivers with respect to the installation position of one of the receivers using the positioning signals received by the two receivers. Note that the present invention is not limited to this in other embodiments. For example, the transport vehicle 200 may include an inertial measurement unit (IMU), and the orientation may be calculated based on the measurement results of the inertial measurement unit. In this case, the drift of the inertial measurement unit may be corrected based on the travel trajectory of the transport vehicle 200.

[0013] The control device 220 transmits the position detected by the position and orientation calculator 210 and the calculated orientation to the control device 300. The control device 220 receives course data, a dumping instruction, an instruction to enter the loading point P3, and an instruction to start from the loading point P3 from the control device 300. The control device 220 runs the transport vehicle 200 according to the received course data, or raises and lowers the body 201 of the transport vehicle 200 according to the dumping instruction. When the transport vehicle reaches and stops at the destination based on the instruction, the control device 220 transmits a reach notification indicating the arrival at the destination (for example, the loading point P3 shown in FIG. 4) to the control device 300.

[0014] 《Working Machine 100》 FIG. 2 is an external view of the working machine 100 according to the first embodiment. The working machine 100 according to the first embodiment is a hydraulic excavator. Note that the working machine 100 according to other embodiments may be a work vehicle other than a hydraulic excavator. The working machine 100 includes a working device 110 that operates hydraulically, a revolving body 120 that supports the working device 110, and a traveling body 130 that supports the revolving body 120.

[0015] The working device 110 includes a boom 111, an arm 112, a bucket 113, a boom cylinder 114, an arm cylinder 115, a bucket cylinder 116, a boom angle sensor 117, an arm angle sensor 118, and a bucket angle sensor 119.

[0016] The base end portion of the boom 111 is attached to the front portion of the revolving body 120 via a pin. The arm 112 connects the boom 111 and the bucket 113. The base end portion of the arm 112 is attached to the tip end portion of the boom 111 via a pin. The bucket 113 includes a blade for excavating excavated materials such as earth and sand and a container for transporting the excavated materials. The base end portion of the bucket 113 is attached to the tip end portion of the arm 112 via a pin. Examples of the excavated materials include earth and sand, ore, crushed stone, coal, and the like.

[0017] The boom cylinder 114 is a hydraulic cylinder for operating the boom 111. The base end portion of the boom cylinder 114 is attached to the slewing body 120. The tip end portion of the boom cylinder 114 is attached to the boom 111. The arm cylinder 115 is a hydraulic cylinder for driving the arm 112. The base end portion of the arm cylinder 115 is attached to the boom 111. The tip end portion of the arm cylinder 115 is attached to the arm 112. The bucket cylinder 116 is a hydraulic cylinder for driving the bucket 113. The base end portion of the bucket cylinder 116 is attached to the arm 112. The tip end portion of the bucket cylinder 116 is attached to the bucket 113.

[0018] The boom angle sensor 117 is attached to the boom 111 and detects the inclination angle of the boom 111. The arm angle sensor 118 is attached to the arm 112 and detects the inclination angle of the arm 112. The bucket angle sensor 119 is attached to the bucket 113 and detects the inclination angle of the bucket 113. The boom angle sensor 117, the arm angle sensor 118, and the bucket angle sensor 119 according to the first embodiment detect the inclination angle with respect to the ground plane. Note that the angle sensors according to other embodiments are not limited to this, and may detect the inclination angle with respect to other reference planes. For example, in other embodiments, the angle sensor may detect the relative angle with respect to the attachment portion, or may detect the inclination angle by measuring the stroke of each cylinder and converting the stroke of the cylinder into an angle.

[0019] The working machine 100 includes a position and orientation calculator 123, an inclination measuring device 124, and a control device 125.

[0020] The position and orientation calculator 123 calculates the position of the revolving body 120 and the orientation in which the revolving body 120 faces. The position and orientation calculator 123 includes two receivers that receive positioning signals from artificial satellites constituting GNSS. The two receivers are installed at different positions of the revolving body 120 respectively. The position and orientation calculator 123 detects the position of the representative point (for example, the center of rotation of the revolving body 120) of the revolving body 120 in the field coordinate system based on the positioning signal received by one of the receivers. The position and orientation calculator 123 calculates the orientation in which the revolving body 120 faces as the relationship between the installation positions of the two receivers with respect to the installation position of one of the receivers, using the positioning signals received by the two receivers. Note that the control device 125 can convert the position in the field coordinate system and the position in the machine coordinate system with respect to each other by using the position of the representative point of the revolving body 120 in the field coordinate system. The machine coordinate system is an orthogonal coordinate system based on the representative point of the revolving body 120.

[0021] The inclination measuring device 124 measures the acceleration and angular velocity of the revolving body 120, and detects the attitude (for example, roll angle, pitch angle, yaw angle) of the revolving body 120 based on the measurement results. The inclination measuring device 124 is installed, for example, on the lower surface of the revolving body 120. The inclination measuring device 124 can use, for example, an inertial measurement unit (IMU).

[0022] The control device 125 transmits the turning speed, position and orientation of the revolving body 120, the tilt angles of the boom 111, arm 112 and bucket 113, the traveling speed of the traveling body 130, and the attitude of the revolving body 120 to the control device 300. Hereinafter, the data collected by the working machine 100 or the transport vehicle 200 from various sensors is also referred to as vehicle data. Note that the vehicle data according to other embodiments is not limited to this. For example, the vehicle data according to other embodiments may not include any of the turning speed, position, orientation, tilt angle, traveling speed, and attitude, or may include values detected by other sensors, or may include values calculated from the detected values. The control device 125 receives a control instruction from the supervision device 300. The control device 125 drives the working machine 110, the revolving body 120, or the traveling body 130 according to the received control instruction. When the driving based on the control instruction is completed, the control device 125 transmits a completion notice of the automatic excavation loading control to the supervision device 300. The detailed configuration of the control device 125 will be described later.

[0023] 《Supervision Device 300》 FIG. 3 is a schematic block diagram showing the configuration of the supervision device 300 according to the first embodiment. The supervision device 300 manages the operation of the working machine 100 and the traveling of the transport vehicle 200. The supervision device 300 is a computer including a processor 310, a main memory 330, a storage 350, and an interface 370. The storage 350 stores programs. The processor 310 reads a program from the storage 350, expands it in the main memory 330, and executes processing according to the program. The supervision device 300 is connected to a network via the interface 370. Examples of the processor 310 include a CPU (Central Processing Unit), a GPU (Graphic Processing Unit), and a microprocessor.

[0024] The program may be for realizing a part of the functions to be exerted by the computer of the control device 300. For example, the program may exert functions by combination with other programs already stored in the storage, or by combination with other programs implemented in other devices. In other embodiments, in addition to or instead of the above configuration, the control device 300 may include a custom LSI (Large Scale Integrated Circuit) such as a PLD (Programmable Logic Device). Examples of PLDs include PAL (Programmable Array Logic), GAL (Generic Array Logic), CPLD (Complex Programmable Logic Device), and FPGA (Field Programmable Gate Array). In this case, part or all of the functions realized by the processor 310 may be realized by the integrated circuit. Such an integrated circuit is also included as an example of a processor.

[0025] The storage 350 has storage areas as the control position storage unit 351 and the travel route storage unit 352. Examples of the storage 350 include a magnetic disk, a magneto-optical disk, an optical disk, a semiconductor memory, and the like. The storage 350 may be an internal medium directly connected to the common communication line of the control device 300, or may be an external medium connected to the control device 300 via the interface 370. The storage 350 is a non-temporary tangible storage medium.

[0026] The control position storage unit 351 stores the position data of the excavation point P22 (see FIG. 6) and the loading point P3. The excavation point P22 and the loading point P3 are points set, for example, in advance by the operation of an administrator or the like at the work site. Note that the position data of the excavation point P22 and the loading point P3 stored in the control position storage unit 351 may be updated by an administrator or the like according to the progress of the work or the like.

[0027] FIG. 4 is a diagram showing an example of a travel route. The travel route memory unit 352 stores the travel route R for each transport vehicle 200. The travel route R includes a predetermined connection route R1 that connects two areas A (for example, the loading area A1 and the dumping area A2), and the approach route R2, the approach route R3, and the exit route R4 that are routes within the area A. The approach route R2 is a route that connects the standby point P1, which is one end of the connection route R1 within the area A, and a predetermined turning point P2. The approach route R3 is a route that connects the turning point P2 within the area A and the loading point P3 or the dumping point P4. The exit route R4 is a route that connects the loading point P3 or the dumping point P4 within the area A and the exit point P5, which is the other end of the connection route R1. The turning point P2 is a point set by the control device 300 according to the position of the loading point P3. The control device 300 calculates the approach route R2, the approach route R3, and the exit route R4 each time the loading point P3 is changed.

[0028] The processor 310 includes, by executing a program, a collection unit 311, a transport vehicle identification unit 312, a travel course generation unit 313, a notification reception unit 314, a vessel identification unit 315, and an automatic excavation and loading instruction unit 316.

[0029] The collection unit 311 collects vehicle data from the work machine 100 and the transport vehicle 200 via the access point 400.

[0030] The transport vehicle identification unit 312 identifies the transport vehicle 200 to be loaded with the excavated material based on the vehicle data of the transport vehicle 200 collected by the collection unit 311. The travel course generation unit 313 generates course data indicating an area where the movement of the transport vehicle 200 is permitted based on the travel route stored in the travel route memory unit 352 and the vehicle data collected by the collection unit 311, and transmits the course data to the transport vehicle 200. The course data is, for example, data representing an area where the transport vehicle 200 can travel at a predetermined speed within a certain time and does not overlap with the travel routes of other transport vehicles 200.

[0031] The notification receiving unit 314 receives a completion notification of the automatic excavation loading control from the working machine 100 and a notification of arrival at the loading point P3 from the transport vehicle 200.

[0032] When the vessel specifying unit 315 receives a notification of arrival at the loading point P3 from the transport vehicle 200, it specifies the position of the vessel 201 in the site coordinate system based on the vehicle data of the transport vehicle 200. For example, the vessel specifying unit 315 specifies the center position of the bottom surface of the vessel 201. The vessel specifying unit 315 specifies the position of the vessel 201, for example, according to the following procedure. The vessel specifying unit 315 arranges the three-dimensional data representing the shape of the transport vehicle 200 including the vessel 201 at the position indicated by the position data of the transport vehicle 200 such that the bottom surface of the vessel 201 faces upward. Then, the vessel specifying unit 315 rotates the three-dimensional data in the direction indicated by the azimuth data of the transport vehicle 200 to specify the position of the vessel 201 in the site coordinate system. The vessel specifying unit 315 transmits the specified position of the vessel 201 to the working machine 100.

[0033] The automatic excavation loading instruction unit 316 transmits an automatic excavation loading instruction including the position of the excavation point P22 and the position of the loading point P3 stored in the control position storage unit 351 to the working machine 100.

[0034] 《Control Device 125 of the Working Machine》 FIG. 5 is a schematic block diagram showing the configuration of the control device 125 of the working machine according to the first embodiment. The control device 125 controls the actuator of the working machine 100 based on the instruction of the control device 300. The control device 125 is a computer including a processor 1210, a main memory 1230, a storage 1250, and an interface 1270. The storage 1250 stores programs. The processor 1210 reads a program from the storage 1250, expands it in the main memory 1230, and executes processing according to the program. The control device 125 is connected to a network via the interface 1270. Examples of the processor 1210 include a CPU (Central Processing Unit), a GPU (Graphic Processing Unit), and a microprocessor.

[0035] The program may be for realizing a part of the functions to be exerted on the computer of the control device 125. For example, the program may exert functions in combination with other programs already stored in the storage or in combination with other programs implemented in other devices. In other embodiments, the control device 125 may include a custom LSI such as a PLD in addition to or instead of the above configuration. In this case, part or all of the functions realized by the processor 1210 may be realized by the integrated circuit. Such an integrated circuit is also included as an example of a processor.

[0036] Examples of the storage 1250 include a magnetic disk, a magneto-optical disk, an optical disk, and a semiconductor memory. The storage 1250 may be an internal medium directly connected to the common communication line of the control device 125, or may be an external medium connected to the control device 125 via the interface 1270. The storage 1250 is a non-transitory tangible storage medium.

[0037] The processor 1210 includes, when executing a program, a vehicle data acquisition unit 1211, a bucket identification unit 1212, an instruction reception unit 1213, a coordinate conversion unit 1214, an avoidance position identification unit 1215, an excavation position identification unit 1216, a lowering stop determination unit 1217, a start position determination unit 1218, a down swing control unit 1219, an excavation control unit 1220, a hoist swing control unit 1221, a soil discharge control unit 1222, an avoidance control unit 1223, and a command output unit 1224.

[0038] The vehicle data acquisition unit 1211 acquires vehicle data from various sensors provided in the working machine 100 and transmits the acquired vehicle data to the control device 300.

[0039] The bucket identification unit 1212 identifies the position of the bucket 113 in the machine coordinate system with respect to the working machine 100 based on the vehicle data acquired by the vehicle data acquisition unit 1211. The bucket identification unit 1212 identifies the positions of a plurality of points on the contour of the bucket 113 including the cutting edge and the bottom. The contour of the bucket 113 refers to a line that divides different surfaces (for example, a side surface and a bottom surface, etc.) of the shape of the bucket 113. The bucket identification unit 1212 identifies the positions of at least a plurality of points on the contour when the bucket 113 is viewed from the side. Specifically, the bucket identification unit 1212 identifies the positions of a plurality of points on the contour of the bucket 113 according to the following procedure. The bucket identification unit 1212 obtains the position of the tip of the boom 111 based on the absolute angle of the boom 111 obtained from the inclination angle of the boom 111 and the known length of the boom 111 (the distance from the pin at the base end to the pin at the tip). The bucket identification unit 1212 obtains the absolute angle of the arm 112 based on the absolute angle of the boom 111 and the inclination angle of the arm 112. The bucket identification unit 1212 obtains the position of the tip of the arm 112 based on the position of the tip of the boom 111, the absolute angle of the arm 112, and the known length of the arm 112 (the distance from the pin at the base end to the pin at the tip). The bucket specifying unit 1212 obtains the absolute angle of the bucket 113 based on the absolute angle of the arm 112 and the tilt angle of the bucket 113. The bucket specifying unit 1212 obtains the positions of a plurality of points on the contour of the bucket 113 based on the position of the tip of the arm 112, the absolute angle of the bucket 113, and the distances from the pins of the bucket 113 to the plurality of points on the contour of the bucket 113.

[0040] The instruction receiving unit 1213 receives an automatic excavation loading instruction from the control device 300. The instruction receiving unit 1213 determines that the automatic excavation loading control is started upon receiving the automatic excavation loading instruction. The automatic excavation loading control includes automatic soil discharge control. That is, the instruction receiving unit 1213 is an example of an automatic control determination unit that determines whether to start the automatic soil discharge control.

[0041] The coordinate conversion unit 1214 receives the position of the vessel 201 of the transport vehicle 200 from the control device 300, and converts the position of the vessel 201 from the field coordinate system to the machine coordinate system based on the vehicle data acquired by the vehicle data acquisition unit 1211. The coordinate conversion unit 1214 is an example of a loading container specifying unit that specifies the position of the vessel 201 in the machine coordinate system.

[0042] FIG. 6 is a diagram showing an example of the trajectory of the bucket before excavation in the automatic excavation loading control according to the first embodiment. The avoidance position specifying unit 1215 specifies an interference avoidance position P02, which is a point where the working machine 110 and the transport vehicle 200 do not interfere in a plan view from above, based on the position of the working machine 100, the position of the vessel 201, and the position of the pin of the bucket 113 at the start of control (the no-load swing start position P01). The interference avoidance position P02 has the same height as the no-load swing start position P01, the distance from the swing center of the swing body 120 is equal to the distance from the swing center to the soil discharge start position P07, and there is no transport vehicle 200 below. Note that the pin of the bucket 113 moves to the no-load swing start position P01, which is higher than the soil discharge start position P07, by the soil discharge control described later. The avoidance position specifying unit 1215 specifies, for example, a circle centered on the swing center of the swing body 120 and having a radius equal to the distance between the swing center and the no-load swing start position P01, and among the positions on the circle, the position closest to the no-load swing start position P01 where the outer shape of the bucket 113 does not interfere with the transport vehicle 200 in a plan view from above is specified as the interference avoidance position P02. The avoidance position specifying unit 1215 can determine whether the transport vehicle 200 and the bucket 113 interfere based on the position of the transport vehicle 200 and the positions of a plurality of points on the contour of the bucket 113. Here, "the same height" and "equal distance" do not necessarily mean that the height or distance is exactly the same, and some error or margin is allowed.

[0043] The excavation position specifying unit 1216 specifies, as the excavation position P05, a point that is separated from the excavation point P22 included in the automatic excavation loading instruction by the distance from the pin of the bucket 113 to the cutting edge. That is, when the bucket 113 is in a predetermined excavation posture with the cutting edge facing the soil discharge direction, when the cutting edge of the bucket 113 is located at the excavation point P22, the pin of the bucket 113 is located at the excavation position P05. Further, the excavation position specifying unit 1216 determines, as the swing end position P04, a position that is a predetermined height above the excavation position P05.

[0044] When the lowering stop determination unit 1217 is performing the lowering operation of the work implement 110 simultaneously with the no-load turning of the revolving body 120, it determines whether or not the height of the pin of the bucket 113 has reached the same height as the turning end position P04. The position of the tip of the arm 112 at this time is referred to as the lowering stop position P03.

[0045] FIG. 7 is a diagram showing an example of the trajectory of the bucket after excavation in the automatic excavation loading control according to the first embodiment. The start position determination unit 1218 determines the dump start position P07 based on the position of the vessel 201. Specifically, the start position determination unit 1218 determines the height of the dump start position P07 to be the height of the vessel 201 plus the amount of change in the height of the bucket 113 by the automatic dumping control, the height of the bucket 113, and the height of the control margin of the bucket 113, which are obtained in advance. The height of the bucket 113 is, for example, the height from the ground surface to the lowest point of the bucket 113. The height of the control margin is a margin determined according to the variation in the height error of the bucket 113 caused by sensor error or control delay. The moving distance of the lowest point of the bucket 113 by the automatic dumping control will be described later. In addition, the start position determination unit 1218 changes the longitudinal component of the vessel 201 at the dump start position P07 according to the number of loading times into the same transport vehicle 200. Specifically, the start position determination unit 1218 determines the initial dump start position P07 at a position on the back side (front side of the transport vehicle 200) of the vessel 201, and moves the dump start position P07 to a position on the front side (rear side of the transport vehicle 200) of the vessel 201 as the number of loading times increases.

[0046] When the instruction receiving unit 1213 receives a digging loading instruction, the down swing control unit 1219 generates commands for controlling the swing body 120, the boom 111, the arm 112, and the bucket 113 to move the bucket 113 to the digging position P05 based on the digging position P05 and the interference avoidance position P02. That is, the down swing control unit 1219 generates each command so as to reach the digging position P05 via the no-load swing start position P01, the interference avoidance position P02, the lowering stop position P03, and the swing end position P04. Note that the down swing means rotating the swing body 120 while lowering the boom 111 to move the bucket 113 from above the vessel 201 to the digging position.

[0047] When the bucket 113 reaches the digging position P05, the digging control unit 1220 generates commands for rotating and moving the bucket 113 in the digging direction.

[0048] Based on the dumping start position P07 and the interference avoidance position P02, the hoist slewing control unit 1221 generates commands for controlling the slewing body 120, the boom 111, the arm 112, and the bucket 113 to move the bucket 113 to the dumping start position P07. That is, the hoist slewing control unit 1221 generates each command so as to reach the dumping start position P07 from the excavation completion position P05' via the loading slewing start position P06 and the interference avoidance position P02. At this time, the hoist slewing control unit 1221 generates a command to rotate the bucket 113 so that the height of the bucket 113 does not change even when the boom 111 and the arm 112 are driven. When the dumping start position P07 is lower than the interference avoidance position P02, the hoist slewing control unit 1221 outputs only a command to slew the slewing body 120 from the interference avoidance position P02, and after the pin of the bucket 113 reaches the dumping start position P07, outputs a command to lower the boom 111 to move the pin of the bucket 113 to the dumping start position P07. The hoist slewing control unit 1221 is an example of a dumping position adjustment unit that generates a command to rotate the boom 111 so that the bucket 113 moves to the dumping start position P07. Note that hoist slewing means slewing the slewing body 120 while raising the boom 111 to move the bucket 113 holding the earth and sand onto the vessel 201.

[0049] When the bucket 113 reaches the dumping start position P07, the dumping control unit 1222 generates commands for controlling the boom 111, the arm 112, and the bucket 113 to rotate the bucket 113 in the dumping direction. FIG. 8 is a diagram showing an example of the trajectory of the bucket during dumping in the automatic excavation loading control according to the first embodiment. The dumping control unit 1222 generates each command according to the following procedure to suppress fluctuations in the height of the bucket 113. The dumping control unit 1222 generates a command to rotate the bucket 113 in the dumping direction until the inclination of the bucket 113 reaches a predetermined dumping completion angle. During the rotation of the bucket 113, the dumping control unit 1222 generates a command for driving the boom 111 and the arm 112 so that the bucket 113 rotates about the geometric center of gravity G on the side surface of the bucket 113, for example. The locus Lp of the pin of the bucket 113 during automatic dumping control by the dumping control unit 1222 is obtained in advance by calculation. The dumping control unit 1222 generates a command for driving the boom 111 and the arm 112 so that the pin of the bucket 113 moves along the locus Lp.

[0050] The locus Lg of the geometric center of gravity G of the bucket 113 when the bucket 113 is rotated in the dumping direction until the absolute angle of the bucket 113 reaches the dumping completion angle can be obtained in advance by calculation. In FIG. 8, the position and inclination of the bucket 113 at the start of dumping are represented by the bucket 113 drawn with a solid line. Also, the position and inclination of the bucket 113 when the bucket 113 is rotated while maintaining the position of the pin of the bucket 113 are represented by the bucket 113 drawn with a broken line. Note that the absolute angle of the bucket 113 is, for example, the angle of the bucket 113 with respect to the axis in the vehicle body coordinate system or the site coordinate system. By rotating the locus Lg by 180 degrees and aligning the starting point with the pin of the bucket 113, the locus Lp of the pin of the bucket 113 for keeping the position of the geometric center of gravity G constant can be obtained. In FIG. 8, the position and inclination of the bucket 113 when the bucket 113 is rotated while moving the pin of the bucket 113 along the locus Lp are represented by the bucket 113 drawn with a one-dot chain line. Note that when the locus obtained by inverting the locus Lg has a maximum point M, that is, when the locus obtained by inverting the locus Lg descends from the middle, the locus Lp of the pin of the bucket 113 is determined to move horizontally from the maximum point M. The locus obtained by inverting the locus Lg is represented by a broken-line arrow in FIG. 8. This is to prevent the behavior of the working machine 110 from becoming unstable due to the driving direction of the boom 111 switching from the raising direction to the lowering direction at the maximum point. As shown in Fig. 8, the trajectory Lp of the pin heads upward and forward of the bucket 113. Therefore, the dump control unit 1222 outputs a command to rotate the boom 111 upward while the inclination of the bucket 113 changes from the inclination at the start of the automatic dump control to the dump completion angle. Further, the dump control unit 1222 outputs a command to rotate the arm in the pulling direction while the inclination of the bucket 113 changes from the inclination at the start of the automatic dump control to the dump completion angle. As shown in Fig. 8, when the bucket 113 is rotated while moving the pin of the bucket 113 along the trajectory Lp, the moving distance d1 of the lowest point of the bucket 113 is smaller than the moving distance d0 when the bucket 113 is rotated about the pin of the bucket 113. Thus, the moving distance d1 of the lowest point of the bucket 113 by the automatic dump control can be obtained in advance.

[0051] Figs. 9 and 10 are diagrams showing examples of avoidance control according to the first embodiment. When the distance between the bucket 113 and the vessel 201 is within a predetermined proximity threshold th, the avoidance control unit 1223 generates a command to rotate the boom 111 in the upward direction or a command to rotate the arm 112 in the retracting direction, and stops the output of the command for driving the bucket 113. Specifically, the avoidance control unit 1223 generates a command to drive the boom 111 or the arm 112 so as to move the bucket 113 in the extending direction of the line segment V that connects the vessel 201 and the bucket 113 at the shortest distance. For example, as shown in FIG. 9, when the distance between the bottom surface of the vessel 201 and the bucket 113 is the shortest, the avoidance control unit 1223 drives the boom 111 so that the bucket 113 moves upward in the extending direction of the line segment V that connects the vessel 201 and the bucket 113 at the shortest distance. On the other hand, as shown in FIG. 10, when the distance between the front panel portion of the vessel 201 and the bucket 113 is the shortest, the avoidance control unit 1223 drives the arm 112 so that the bucket 113 moves in the backward direction of the extending line segment V that connects the vessel 201 and the bucket 113 at the shortest distance. Note that the avoidance control unit 1223 may output a command to stop the driving of the bucket 113 instead of stopping the output of the command for driving the bucket 113. In other embodiments, the avoidance control unit 1223 may drive the boom 111 so that the bucket 113 moves upward when the distance between the side gate portion of the vessel 201 and the bucket 113 is the shortest.

[0052] The command output unit 1224 outputs various commands.

[0053] 《Automatic Excavation Loading Control》 FIG. 11 is a flowchart showing a method for outputting an automatic excavation loading instruction by the control device according to the first embodiment. When the notification receiving unit 314 of the control device 300 receives a notification of arrival from the transport vehicle 200 at the loading point P3 (step S1), the vessel identification unit 315 acquires vehicle data from the transport vehicle 200 (step S2). The vessel identification unit 315 identifies the position of the vessel 201 in the site coordinate system based on the acquired vehicle data (step S3). The vessel identification unit 315 transmits the identified position of the vessel 201 to the working machine 100. The automatic excavation loading instruction unit 316 reads the positions of the excavation point P22 and the loading point P3 from the control position storage unit 351 (step S4). The automatic excavation loading instruction unit 316 transmits an automatic excavation loading instruction including the read positions of the excavation point P22 and the loading point P3 to the working machine 100 (step S5).

[0054] FIG. 12 is a flowchart showing automatic excavation loading control by the working machine according to the first embodiment. When the instruction receiving unit 1213 of the control device 125 receives an input of an automatic excavation loading instruction from the control device 300, it executes the automatic excavation loading control shown in FIG. 12. During the automatic excavation loading control, the vehicle data acquisition unit 1211 acquires the position and orientation of the slewing body 120, the tilt angles of the boom 111, the arm 112, and the bucket 113, and the posture of the slewing body 120 at a predetermined cycle.

[0055] The coordinate conversion unit 1214 acquires the position of the vessel 201 in the site coordinate system from the control device 300 (step S101). The coordinate conversion unit 1214 converts the position of the vessel 201 from the site coordinate system to the machine coordinate system based on the position, orientation, and posture of the slewing body 120 acquired by the vehicle data acquisition unit 1211 (step S102).

[0056] The bucket identification unit 1212, the avoidance position identification unit 1215, the excavation position identification unit 1216, and the start position determination unit 1218 respectively determine the empty-load slewing start position P01, the interference avoidance position P02, the slewing end position P04, and the soil discharge start position P07 (step S103).

[0057] Based on each control position determined in step S103, the downswing control unit 1219 generates commands to drive the swing body 120, the boom 111, the arm 112, and the bucket 113 so as to reach the excavation position P05. The command output unit 1224 outputs each generated command (step S104).

[0058] When the bucket 113 reaches the excavation position P05, the excavation control unit 1220 generates commands to drive the arm 112 and the bucket 113 in order to rotate the bucket 113 in the excavation direction and also move it. The command output unit 1224 outputs each generated command (step S105).

[0059] When the excavation control in step S105 ends, the hoist swing control unit 1221 generates commands for controlling the swing body 120, the boom 111, the arm 112, and the bucket 113 in order to move the bucket 113 to the soil discharge start position P07 based on each control position determined in step S103. The command output unit 1224 outputs each command generated in step S111 (step S106).

[0060] When the bucket 113 reaches the soil discharge start position P07, the avoidance control unit 1223 determines whether the distance between the bucket 113 and the vessel 201 is within a predetermined proximity threshold (step S107). When the distance between the bucket 113 and the vessel 201 is not within the predetermined proximity threshold (step S107: NO), the soil discharge control unit 1222 generates a command to rotate the bucket 113 in the soil discharge direction at a constant angular velocity (step S108). The soil discharge control unit 1222 generates commands to drive the boom 111 and the arm 112 by PID control based on the position of the pin of the bucket 113 and the locus Lp (step S109). That is, the soil discharge control unit 1222 generates a command to rotate the boom 111 in the upward direction and a command to rotate the arm 112 in the pulling direction. The command output unit 1224 outputs the command generated in step S108 and the commands generated in step S109 (step S110).

[0061] When the distance between the bucket 113 and the vessel 201 is within a predetermined proximity threshold (step S107: YES), the avoidance control unit 1223 determines whether the distance between the bucket 113 and the vessel 201 in the height direction is within the predetermined proximity threshold (step S111). When the distance between the bucket 113 and the vessel 201 is within the proximity threshold in the height direction (step S111: YES), the avoidance control unit 1223 generates a command to rotate the boom 111 in the upward direction (step S112). Further, the avoidance control unit 1223 determines whether the distance between the bucket 113 and the vessel 201 in the horizontal direction is within the predetermined proximity threshold (step S113). When the distance between the bucket 113 and the vessel 201 is within the proximity threshold in the horizontal direction (step S113: YES), the avoidance control unit 1223 generates a command to rotate the arm 112 in the retracting direction (step S114). The command output unit 1224 outputs at least one of the command generated in step S107 and the command generated in step S108 (step S115). At this time, the command output unit 1224 does not output a command to rotate the bucket 113.

[0062] The waste discharge control unit 1222 determines whether the inclination of the bucket 113 has reached the waste discharge completion angle (step S116). When the inclination of the bucket 113 has not reached the waste discharge completion angle (step S116: NO), the control device 125 returns the process to step S107 and continues the waste discharge control. On the other hand, when the inclination of the bucket 113 has reached the waste discharge completion angle (step S116: YES), the waste discharge control unit 1222 determines whether the number of loading times into the same transport vehicle 200 has reached a predetermined number of times (step S117). When the number of loading times into the same transport vehicle 200 has not reached the predetermined number of times (step S117: NO), it returns to step S101, and the control device 125 executes the automatic excavation and loading control again. On the other hand, when the number of loading times into the same transport vehicle 200 has reached the predetermined number of times (step S117: YES), the waste discharge control unit 1222 transmits a completion notification of the automatic excavation and loading control to the control device 300 (step S118) and ends the process.

[0063] 《Function and Effect》 Thus, when it is determined to start the automatic dumping control, the control device 125 of the working machine 100 according to the first embodiment generates a command to rotate the bucket 113 in the dumping direction until the inclination of the bucket 113 reaches the dumping completion angle, and generates a command to rotate the boom 111 in the upward direction while the inclination of the bucket 113 changes from the inclination at the start of the automatic dumping control to the dumping completion angle. That is, since the decrease in the height of the bucket 113 can be canceled by the upward movement of the boom 111, the variation in the height of the bucket 113 can be reduced. Note that the smaller the vessel 201 of the transport vehicle 200 is with respect to the bucket 113, the greater the effect of reducing the variation in the height of the bucket 113 because the locus of the bucket 113 can be made smaller.

[0064] Also, the control device 125 according to the first embodiment generates a command to rotate the arm 112 in the pulling direction while the inclination of the bucket 113 changes from the inclination at the start of the automatic dumping control to the dumping completion angle. Thereby, the variation in the dropping point of the excavated material can be reduced. When the bucket 113 is rotated in the dumping direction without moving the arm 112, the horizontal position of the cutting edge of the bucket 113 moves with the rotation. On the other hand, by rotating the arm 112 in the pulling direction while the bucket 113 is rotating in the dumping direction, the horizontal movement of the cutting edge of the bucket 113 can be canceled. Note that the control device 125 according to other embodiments may move the boom 111 in the upward direction and not move the arm 112.

[0065] In addition, the control device 125 according to the first embodiment generates a command so that the amount of movement of the geometric center of gravity G on the side surface of the bucket 113 is reduced as compared with the case where the boom 111 and the arm 112 are not controlled. Note that, in other embodiments, the present invention is not limited to this. For example, the control device 125 according to another embodiment may generate a command so that the amount of movement of the center point of the circumscribed circle in contact with the contour of the side surface of the bucket 113 is reduced. Note that if the control device 125 generates a command so that the amount of movement of a point inside the circle having a line segment connecting the cutting edge and the pin of the bucket 113 as the diameter is reduced, the amount of movement of the bucket 113 can be appropriately reduced.

[0066] In addition, when the distance between the contour of the bucket and the vessel 201 is within the proximity threshold value, the control device 125 according to the first embodiment generates a command to rotate the boom 111 in the upward direction or a command to rotate the arm 112 in the pulling direction, and stops the output of the command for driving the bucket 113. Thereby, even when a disturbance such as rattling of the scaffold of the working machine 100 occurs, the possibility of contact between the bucket 113 and the vessel 201 can be reduced.

[0067] According to the first embodiment, the horizontal position of the soil discharge start position varies according to the number of times of automatic soil discharge control for the same transport vehicle 200. Thereby, it is possible to avoid concentration of the soil discharge position on the transport vehicle 200 and prevent the excavated material from spilling from the vessel 201.

[0068] <Other Embodiments> As described above, one embodiment has been described in detail with reference to the drawings. However, the specific configuration is not limited to the above, and various design changes and the like are possible. That is, in other embodiments, the order of the above-described processes may be appropriately changed. Also, some processes may be executed in parallel.

[0069] In the above-described embodiment, the construction machine 100 is automatically controlled by the control device 300, but the present invention is not limited thereto. For example, the construction machine 100 according to another embodiment may be operated by an operator. In this case, the operator may output an automatic excavation loading instruction to the control device 125 by pressing an automatic excavation loading button (not shown) provided in the driver's seat. Further, in another embodiment, the construction machine 100 may transmit and receive signals by vehicle-to-vehicle communication instead of communication via an access point.

[0070] The control device 125 according to the above-described embodiment may be configured by a single computer, or the configuration of the control device 125 may be divided and arranged in a plurality of computers, and the plurality of computers may function as the control device 125 by cooperating with each other. At this time, a part of the control device 125 may be realized by the control device 300.

Explanation of Reference Numerals

[0071] 100... Construction machine 110... Working machine 111... Boom 112... Arm 113... Bucket 120... Swing body 130... Traveling body 125... Control device 1211... Vehicle data acquisition unit 1212... Bucket identification unit 1213... Instruction reception unit 1214... Coordinate conversion unit 1215... Avoidance position identification unit 1216... Excavation position identification unit 1217... Lowering stop determination unit 1218... Start position determination unit 1219... Downward swing control unit 1220... Excavation control unit 1221... Hoist swing control unit 1222... Earth discharge control unit 1223... Avoidance control unit 1224... Command output unit 200... Transport vehicle 201... Vessel 300... Control device

Claims

1. A control system for a work machine including a work machine body including a rotating body, a traveling body supporting the rotating body, a boom rotatably attached to the work machine body, an arm rotatably attached to a tip of the boom, and a bucket rotatably attached to a tip of the arm, a soil discharge control unit that generates a first command to rotate the bucket in a soil discharge direction when starting automatic soil discharge control, and generates a second command to drive the boom and the arm so as to reduce the amount of movement of a side surface of the bucket; Equipped with The soil discharge control unit generates the second command to drive the boom and the arm so that the bucket rotates about a geometric center of gravity of a side surface of the bucket. Control system.

2. The soil discharge control unit generates the second command to drive the boom and the arm during a period from the inclination of the bucket at the start of the automatic soil discharge control to a predetermined soil discharge completion angle. The control system of claim 1 .

3. The soil discharge control unit generates the second command to drive the boom and the arm while the bucket is rotating. The control system of claim 2.

4. The earth removal control unit generates the second command to rotate the boom in a lifting direction so that the bucket reduces the amount of movement of the side surface of the bucket from the start of the automatic earth removal control. The control system of claim 1 .

5. The earth removal control unit generates the second command to rotate the arm in a pulling direction so that the bucket reduces the amount of movement of the side surface of the bucket from the start of the automatic earth removal control.

5. The control system of claim 4.

6. A vessel identification unit that identifies a position of the vessel; a bucket identification unit that identifies a position of a contour of the bucket when viewed from a side; an avoidance control unit that generates a third command to rotate the boom in a lifting direction or a fourth command to rotate the arm in a retracting direction and stops outputting the first command when a distance between an outline of the bucket when viewed from the side and the vessel is within a predetermined proximity threshold value; A control system according to any one of claims 1 to 5, comprising:

7. a soil discharge position adjustment unit that generates a fifth command to rotate the boom so that the bucket moves to a soil discharge start position that is higher than a height of a vessel by an amount equal to or greater than a change in height of the bucket due to the automatic soil discharge control when it is determined that the automatic soil discharge control is to be started Equipped with The earth discharge control unit generates the first command after the lowest point of the bucket has moved to the earth discharge start position. A control system according to any one of claims 1 to 6.

8. The soil discharge position adjustment unit varies a horizontal position of the vessel of the soil discharge start position according to the number of times the automatic soil discharge control is performed on the same vessel.

8. The control system of claim 7.

9. A control method for a work machine including a work machine body including a rotating body, a traveling body supporting the rotating body, a boom rotatably attached to the work machine body, an arm rotatably attached to a tip of the boom, and a bucket rotatably attached to a tip of the arm, comprising: generating a first command for rotating the bucket in a soil discharge direction when starting automatic soil discharge control; generating a second command for driving the boom and the arm in response to the first command so as to reduce a movement amount of a side surface of the bucket; Equipped with In the step of generating the second command, the second command is generated to drive the boom and the arm so that the bucket rotates about a geometric center of gravity of a side surface of the bucket. Control methods.

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