SHOVEL

Abstract

A shovel may include a lower traveling body; an upper turning body turnably mounted on the lower traveling body; and a control device disposed in the upper turning body, wherein the control device includes a processor, and a memory storing a computer-readable program, which when executed, causes the processor to execute a process including recognizing a position subject to a backfilling operation, and generating a target position relating to the backfilling operation.

Description

BACKGROUND

Technical Field

The present disclosure relates to a shovel.

Description of Related Art

Hydraulic excavators known in the related art are typically equipped with a semi-autonomous excavation control system. The excavation control system is configured to perform an autonomous boom-raising turning operation when a predetermined condition is met.

SUMMARY

According to an aspect of the present disclosure, a shovel includes a lower traveling body; an upper turning body turnably mounted on the lower traveling body; and a control device disposed in the upper turning body, wherein the control device includes a processor, and a memory storing a computer-readable program, which when executed, causes the processor to execute a process including recognizing a position subject to a backfilling operation, and generating a target position relating to the backfilling operation.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a side view illustrating a shovel according to an embodiment of the present disclosure.

FIG. 1B is a top view illustrating the shovel according to the embodiment of the present disclosure.

FIG. 2 is a diagram illustrating an example of a configuration of a hydraulic system mounted on a shovel.

FIG. 3A is a diagram illustrating a part of the hydraulic system relating to an operation of an arm cylinder.

FIG. 3B is a diagram illustrating a part of the hydraulic system relating to an operation of a turning hydraulic motor.

FIG. 3C is a diagram illustrating a part of the hydraulic system relating to an operation of a boom cylinder.

FIG. 3D is a diagram illustrating a part of the hydraulic system relating to an operation of a bucket cylinder.

FIG. 4 is a functional block diagram illustrating a controller.

FIG. 5 is a block diagram illustrating an autonomous control function.

FIG. 6 is a block diagram illustrating an autonomous control function.

FIG. 7A is a top view illustrating the shovel performing a backfilling operation.

FIG. 7B is a top view illustrating the shovel performing a backfilling operation.

FIG. 7C is a top view illustrating the shovel performing a backfilling operation.

FIG. 8A is a cross-sectional view illustrating a hole subjected to a backfilling operation.

FIG. 8B is a cross-sectional view illustrating the hole subjected to a backfilling operation.

FIG. 8C is a cross-sectional view illustrating the hole subjected to a backfilling operation.

FIG. 9A is a cross-sectional view illustrating the backfilled hole.

FIG. 9B is a cross-sectional view illustrating the backfilled hole.

FIG. 10A is a top view illustrating the shovel performing another backfilling operation.

FIG. 10B is a cross-sectional view illustrating a hole subject to another backfilling operation.

FIG. 11 is a top view illustrating the shovel performing still another backfilling operation.

FIG. 12A is a cross-sectional view of a hole subjected to yet another backfilling operation.

FIG. 12B is a cross-sectional view illustrating the hole subject to yet another backfilling operation.

FIG. 12C is a cross-sectional view illustrating the hole subject to yet another backfilling operation.

EMBODIMENT OF THE INVENTION

According to an embodiment of the present disclosure, a technique capable of enhancing the efficiency of the backfilling operation can be provided.

First, a shovel 100 as an excavator according to an embodiment of the present disclosure will be described with reference to FIGS. 1A and 1B. FIG. 1A is a side view illustrating the shovel 100, and FIG. 1B is a top view illustrating the shovel 100.

In the present embodiment, a lower traveling body 1 of the shovel 100 includes a crawler 1C. The crawler 1C is driven by a traveling hydraulic motor 2M mounted on the lower traveling body 1. Specifically, the crawler 1C includes a left crawler 1CL and a right crawler 1CR. The left crawler 1CL is driven by a left traveling hydraulic motor 2ML, and the right crawler 1CR is driven by a right traveling hydraulic motor 2MR.

An upper turning body 3 is mounted on the lower traveling body 1 so as to be able to turn through a turning mechanism 2. The turning mechanism 2 is driven by a turning hydraulic motor 2A mounted on the upper turning body 3. However, the turning hydraulic motor 2A may be a turning electric generator as an electric actuator.

A boom 4 is attached to the upper turning body 3. An arm 5 is attached to the tip of the boom 4, and a bucket 6 as an end attachment is attached to the tip of the arm 5. The boom 4, the arm 5, and the bucket 6 constitute an excavation attachment AT which is an example of an attachment. The boom 4 is driven by a boom cylinder 7, the arm 5 is driven by an arm cylinder 8, and the bucket 6 is driven by a bucket cylinder 9.

The boom 4 is supported in a vertically rotatable manner with respect to the upper turning body 3. A boom angle sensor S1 is attached to the boom 4. The boom angle sensor S1 can detect a boom angle β₁ which is a rotation angle of the boom 4. The boom angle β₁ is, for example, a rising angle from a state in which the boom 4 is lowered most. Therefore, the boom angle β₁ is maximum when the boom 4 is raised most.

The arm 5 is rotatably supported with respect to the boom 4. An arm angle sensor S2 is attached to the arm 5. The arm angle sensor S2 can detect an arm angle β₂ which is a rotation angle of the arm 5. The arm angle β₂ is, for example, an opening angle from the state where the arm 5 is most closed. Therefore, the arm angle β₂ is maximum when the arm 5 is most opened.

The bucket 6 is rotatably supported with respect to the arm 5. A bucket angle sensor S3 is attached to the bucket 6. The bucket angle sensor S3 can detect a bucket angle β₃ which is a rotation angle of the bucket 6. The bucket angle β₃ is an opening angle from the state where the bucket 6 is closed most. Therefore, the bucket angle β₃ is maximum when the bucket 6 is opened most.

In the embodiment illustrated in FIGS. 1A and 1B, the boom angle sensor S1, the arm angle sensor S2, and the bucket angle sensor S3 each include a combination of an acceleration sensor and a gyro sensor. However, the boom angle sensor S1, the arm angle sensor S2, and the bucket angle sensor S3 may each be configured to include an acceleration sensor alone. The boom angle sensor S1 may be a stroke sensor attached to the boom cylinder 7, or may be a rotary encoder, a potentiometer, or an inertial measurement device. The same applies to the arm angle sensor S2 and the bucket angle sensor S3.

The upper turning body 3 is provided with a cabin as a driver's compartment, and one or a plurality of power sources are mounted on the upper turning body 3. In the present embodiment, the upper turning body 3 is mounted with an engine 11 as a power source. The upper turning body 3 is mounted with an object detection device 70, an imaging device a body inclination sensor S4, a turning angular velocity sensor S5, and the like. An operation device 26, a controller a display device D1, and a sound output device D2 are provided inside the cabin 10. In this specification, for convenience, the side to which the excavation attachment AT is attached is designated as a front side, and the side to which a counterweight is attached is designated as a back side.

The object detection device 70 is configured to detect an object existing around the shovel 100. The object may be, for example, a person, an animal, a vehicle, a construction machine, a structure, a wall, a fence, or a hole. The object detection device 70 may be, for example, an ultrasonic sensor, a millimeter-wave radar, a stereo camera, a LIDAR, a range image sensor, or an infrared sensor. In the present embodiment, the object detection device 70 includes a front sensor 70F attached to a front end of an upper surface of the cabin 10, a rear sensor 70B attached to a rear end of an upper surface of the upper turning body 3, a left sensor attached to a left end of the upper surface of the upper turning body 3, and a right sensor 70R attached to a right end of the upper surface of the upper turning body 3. Each sensor includes a LIDAR.

The object detection device 70 may be independent of the shovel 100. In this case, the controller 30 may acquire an image of a work site around the shovel output by the object detection device 70 through a communication device. Specifically, the object detection device 70 may be attached to a multicopter for aerial photography, or may be attached to a steel tower, an electric pole, or the like installed at the work site. Then, the controller 30 may acquire information on the work site based on the captured image viewed from above.

The object detection device 70 may be configured to detect a predetermined object within a predetermined area set around the shovel 100. That is, the object detection device 70 may be configured to identify the type of object. For example, the object detection device 70 may be configured to distinguish between a person and an object other than the person (dump trucks, utility poles, fences, holes, or landforms such as sediment piles, etc.). The object detection device 70 may be configured to calculate a distance from the object detection device 70 or the shovel 100 to a recognized object. Thus, when the object to be recognized is a landform, the object detection device 70 can recognize a distance from the object detection device 70 or the shovel 100 to each measuring position of the landform to be measured, and can also recognize an uneven shape of the landform to be measured. When a hole exists in the landform to be measured, the object detection device 70 can also recognize a shape (area, depth, etc.) and a position of the hole.

The imaging device 80 is configured to image an area around the shovel 100. In the present embodiment, the imaging device 80 includes a rear camera 80B attached to the upper rear end of the upper turning body 3, a front camera 80F attached to the upper front end of the cabin 10, a left camera 80L attached to the upper left end of the upper turning body 3, and a right camera 80R attached to the upper right end of the upper turning body 3.

The rear camera 80B is disposed adjacent to the rear sensor 70B, the front camera 80F is disposed adjacent to the front sensor 70F, the left camera 80L is disposed adjacent to the left sensor 70L, and the right camera 80R is disposed adjacent to the right sensor 70R.

The image captured by the imaging device 80 is displayed on the display device D1. The imaging device 80 may be configured to display a viewpoint conversion image such as an overhead view image on the display device D1. The overhead view image is generated by combining images output by the rear camera 80B, the left camera 80L, and the right camera 80R, for example.

The imaging device 80 may be used as the object detection device 70. In this case, the object detection device 70 may be omitted.

The body inclination sensor S4 is configured to detect an inclination of the upper turning body 3 with respect to a predetermined plane. In the present embodiment, the body inclination sensor S4 is an acceleration sensor configured to detect an inclination angle of the upper turning body 3 around the longitudinal axis and an inclination angle around the lateral axis, with respect to a virtual horizontal plane. The longitudinal (front-back) axis and the lateral (left-right) axis of the upper turning body 3 are, for example, orthogonal to each other, and pass through the center point of the shovel, which is one point on the turning axis of the shovel 100.

The turning angular velocity sensor S5 is configured to detect the turning angular velocity of the upper turning body 3. In the present embodiment, the turning angular velocity sensor S5 is a gyro sensor. The turning angular velocity sensor S5 may be a resolver or a rotary encoder. The turning angular velocity sensor S5 may detect rotational velocity. The rotational velocity may be calculated from the turning angular velocity.

Hereinafter, the boom angle sensor S1, the arm angle sensor S2, the bucket angle sensor S3, the body inclination sensor S4, and the turning angular velocity sensor S5 are each also referred to as an attitude detection device.

The display device D1 is a device for displaying information. The sound output device D2 is a device for outputting sound. The operation device 26 is a device used by an operator for operating an actuator.

The controller 30 is a control device configured to control the shovel 100. In the present embodiment, the controller 30 includes a computer having a CPU, a volatile storage device, a nonvolatile storage device, and the like. The controller 30 reads a program corresponding to each function from the nonvolatile storage device, loads the program into the volatile storage device, and causes the CPU to execute a corresponding process. Each function includes, for example, a machine guidance function that guides a manual operation of the shovel 100 by the operator, and a machine control function that automatically supports the manual operation of the shovel 100 by the operator.

Next, an example of a configuration of a hydraulic system mounted on the shovel 100 will be described with reference to FIG. 2. FIG. 2 is a diagram illustrating the example of the configuration of a hydraulic system mounted on the shovel 100. FIG. 2 illustrates a mechanical power transmission line, a hydraulic fluid line, a pilot line, and an electrical control line by double, solid, dashed, and dotted lines, respectively.

The hydraulic system of the shovel 100 mainly includes an engine 11, a regulator 13, a main pump 14, a pilot pump 15, a control valve unit 17, an operation device 26, a discharge pressure sensor 28, an operation pressure sensor 29, a controller 30, and the like.

In FIG. 2, the hydraulic system circulates hydraulic fluid from the main pump 14 driven by the engine 11 through a center bypass conduit line 40 or a parallel conduit line 42 to a hydraulic fluid tank.

The engine 11 is a driving source for the shovel 100. In the present embodiment, the engine 11 is, for example, a diesel engine that operates to maintain a predetermined speed. An output shaft of the engine 11 is coupled to respective input shafts of the main pump 14 and the pilot pump 15.

The main pump 14 is configured to supply hydraulic fluid to the control valve unit 17 via the hydraulic fluid line. In the present embodiment, the main pump 14 is a swashplate type variable displacement hydraulic pump.

The regulator 13 is configured to control a discharge amount (push-off volume volume) of the main pump 14. In the present embodiment, the regulator 13 controls the discharge amount (push-off volume volume) of the main pump 14 by adjusting a swash plate tilt angle of the main pump 14 in response to a control instruction from the controller 30.

The pilot pump 15 is configured to supply hydraulic fluid to hydraulic control device including the operation device 26 via a pilot line. In the present embodiment, the pilot pump 15 is a fixed displacement hydraulic pump. However, the pilot pump 15 may be omitted. In this case, the function of the pilot pump 15 may be implemented by the main pump 14. That is, the main pump 14 may have, apart from a function of supplying hydraulic fluid to the control valve unit 17, a function of supplying hydraulic fluid to the operation device 26 or the like after lowering the pressure of the hydraulic fluid by a restrictor, or the like.

The control valve unit 17 is configured to control a flow of hydraulic fluid in the hydraulic system. In the present embodiment, the control valve unit 17 includes control valves 171 to 176. The control valve 175 includes a control valve 175L and a control valve 175R, and the control valve 176 includes a control valve 176L and a control valve 176R. The control valve unit 17 can selectively supply hydraulic fluid discharged by the main pump 14 to one or more hydraulic actuators through the control valves 171 to 176. The control valves 171 to 176 control flow rates of hydraulic fluid flowing from the main pump 14 to the hydraulic actuators and flow rates of hydraulic fluid flowing from the hydraulic actuators to the hydraulic fluid tank. The hydraulic actuators include a boom cylinder 7, an arm cylinder 8, a bucket cylinder 9, a left traveling hydraulic motor 2ML, a right traveling hydraulic motor 2MR, and a turning hydraulic motor 2A.

The operation device 26 is a device used by an operator for operating an actuator. The actuator includes at least one of a hydraulic actuator and an electric actuator. In the present embodiment, the operation device 26 supplies hydraulic fluid delivered by the pilot pump 15 to a pilot port of the corresponding control valve in the control valve unit 17 via the pilot line. The pressure of the hydraulic fluid supplied to each of the pilot ports (pilot pressure) is a pressure corresponding to an operating direction and an operating amount of a lever or a pedal (not illustrated) of the operation device 26 with respect to a corresponding one of the hydraulic actuators; however, the operation device 26 may be an electric operation device rather than the hydraulic operation device as described above. In this case, the control valve in the control valve unit 17 may be an electromagnetic spool valve.

The discharge pressure sensor 28 is configured to detect a discharge pressure of the main pump 14. In the present embodiment, the discharge pressure sensor 28 outputs a detected value to the controller 30.

The operation pressure sensor 29 is configured to detect an operation of the operation device 26 performed by the operator. In the present embodiment, the operation pressure sensor 29 detects the operation direction and the operation amount of the operation device 26 corresponding to each actuator in the form of pressure (operation pressure), and outputs the detected value to the controller 30 as operation data. The operation content of the operation device 26 may be detected using other sensors other than the operation pressure sensor.

The main pump 14 includes a left main pump 14L and a right main pump 14R. The left main pump 14L is configured to circulate hydraulic fluid to the hydraulic fluid tank via a left center bypass conduit line 40L or a left parallel conduit line 42L. The right main pump 14R is configured to circulate hydraulic fluid to the hydraulic fluid tank via a right center bypass conduit line 40R or a right parallel conduit line 42R.

The left center bypass conduit line 40L is a hydraulic fluid line passing through the control valves 171, 173, 175L, and 176L located within the control valve unit 17. The right center bypass conduit line 40R is a hydraulic fluid line passing through the control valves 172, 174, 175R, and 176R located within the control valve unit 17.

The control valve 171 is a spool valve that supplies hydraulic fluid discharged by the left main pump 14L to the left traveling hydraulic motor 2ML, and switches a flow of hydraulic fluid to discharge the hydraulic fluid discharged by the left traveling hydraulic motor 2ML to the hydraulic fluid tank.

The control valve 172 is a spool valve that supplies the hydraulic fluid discharged by the right main pump 14R to the right traveling hydraulic motor 2MR, and switches the flow of hydraulic fluid to discharge the hydraulic fluid discharged by the right traveling hydraulic motor 2MR to the hydraulic fluid tank.

The control valve 173 is a spool valve that supplies the hydraulic fluid discharged by the left main pump 14L to the turning hydraulic motor 2A, and switches the flow of hydraulic fluid to discharge the hydraulic fluid discharged by the turning hydraulic motor 2A to the hydraulic fluid tank.

The control valve 174 is a spool valve that supplies the hydraulic fluid discharged by the right main pump 14R to the bucket cylinder 9, and switches the flow of hydraulic fluid to discharge the hydraulic fluid in the bucket cylinder 9 to the hydraulic fluid tank.

The control valve 175L is a spool valve that switches the flow of the hydraulic fluid to supply the hydraulic fluid discharged from the left main pump 14L to the boom cylinder 7. The control valve 175R is a spool valve that switches the flow of the hydraulic fluid to supply the hydraulic fluid discharged from the right main pump 14R to the boom cylinder 7, and discharges the hydraulic fluid in the boom cylinder 7 to the hydraulic fluid tank.

The control valve 176L is a spool valve that switches the flow of the hydraulic fluid to supply the hydraulic fluid discharged from the left main pump 14L to the arm cylinder 8, and discharges the hydraulic fluid in the arm cylinder 8 to the hydraulic fluid tank.

The control valve 176R is a spool valve that switches the flow of the hydraulic fluid to supply the hydraulic fluid discharged from the right main pump 14R to the arm cylinder 8, and discharges the hydraulic fluid in the arm cylinder 8 to the hydraulic fluid tank.

The left parallel conduit line 42L is a hydraulic fluid line parallel to the left center bypass conduit line 40L. The left parallel conduit line 42L may supply hydraulic fluid to a further downstream control valve when hydraulic fluid flowing through the left center bypass conduit line is restricted or blocked by either the control valves 171, 173, or 175L. The right parallel conduit line 42R is a hydraulic fluid line parallel to the right center bypass conduit line 40R. The right parallel conduit line 42R may supply hydraulic fluid to a further downstream control valve when hydraulic fluid flowing through the right center bypass conduit line 40R is restricted or blocked by either the control valves 172, 174, or 175R.

The regulator 13 includes a left regulator 13L and a right regulator 13R. The left regulator 13L controls the discharge amount of the left main pump 14L by adjusting a swash plate inclination angle of the left main pump 14L according to the discharge pressure of the left main pump 14L. Specifically, the left regulator 13L reduces the discharge amount by adjusting the swash plate inclination angle of the left main pump 14L according to an increase in the discharge pressure of the left main pump 14L, for example. The same applies to the right regulator 13R. This is because the absorbed power (e.g., absorbed horsepower) of the main pump 14, which is represented by the product of the discharge pressure and the discharge amount, does not exceed the output power (e.g., output horsepower) of the engine 11.

The operation device 26 includes a left operation lever 26L, a right operation lever 26R, and a traveling lever 26D. The traveling lever 26D includes a left traveling lever 26DL and a right traveling lever 26DR.

The left operation lever 26L is one of the operation levers, and is used for turning operation and operation of the arm 5. When the left operation lever 26L is operated in the front-back direction, the hydraulic fluid discharged from the pilot pump 15 is utilized to operate the control pressure corresponding to the lever operation amount on the pilot port of the control valve 176. When the left operation lever 26L is operated in the left-right direction, the hydraulic fluid discharged from the pilot pump is utilized to operate the control pressure corresponding to the lever operation amount on the pilot port of the control valve 173.

Specifically, when the left operation lever 26L is operated in the arm closing direction, the hydraulic fluid is introduced into the right pilot port of the control valve 176L, and the hydraulic fluid is introduced into the left pilot port of the control valve 176R. When the left operation lever 26L is operated in an arm opening direction, the hydraulic fluid is introduced into the left pilot port of the control valve 176L, and the hydraulic fluid is introduced into the right pilot port of the control valve 176R. When the left operation lever 26L is operated in a left turning direction, the hydraulic fluid is introduced into the left pilot port of the control valve 173, and when the left operation lever 26L is operated in a right turning direction, the hydraulic fluid is introduced into the right pilot port of the control valve 173.

The right operation lever 26R is one of the operation levers, and is used for operation of the boom 4 and operation of the bucket 6. When the right operation lever 26R is operated in the front-back direction, the hydraulic fluid discharged from the pilot pump 15 is utilized to operate the control pressure corresponding to the lever operation amount on the pilot port of the control valve 175. When the right operation lever 26R is operated in the left-right direction, the hydraulic fluid discharged from the pilot pump is utilized to operate the control pressure corresponding to the lever operation amount on the pilot port of the control valve 174.

Specifically, when the right operation lever 26R is operated in the boom lowering direction, the hydraulic fluid is introduced into the right pilot port of the control valve 175R. When the right operation lever 26R is operated in the boom raising direction, the hydraulic fluid is introduced into the right pilot port of the control valve 175L, and the hydraulic fluid is introduced into the left pilot port of the control valve 175R. When the right operation lever 26R is operated in the bucket closing direction, the hydraulic fluid is introduced into the left pilot port of the control valve 174, and when the right operation lever 26R is operated in the bucket opening direction, the hydraulic fluid is introduced into the right pilot port of the control valve 174.

The traveling lever 26D is used to operate the crawler 1C. Specifically, the left traveling lever 26DL is used to operate the left crawler 1CL. The left traveling lever 26DL may be configured to be interlocked with the left traveling pedal. When the left traveling lever 26DL is operated in the front-back direction, the hydraulic fluid discharged from the pilot pump 15 is utilized to operate the control pressure corresponding to the lever operation amount on the pilot port of the control valve 171. The right traveling lever 26DR is used to operate the right crawler 1CR. The right traveling lever 26DR may be configured to be interlocked with the right traveling pedal. When operated in the front-back direction, the right traveling lever 26DR utilizes hydraulic fluid discharged from the pilot pump 15 to exert a control pressure corresponding to the lever operation amount on the pilot port of the control valve 172.

The discharge pressure sensor 28 includes a discharge pressure sensor 28L and a discharge pressure sensor 28R. The discharge pressure sensor 28L detects the discharge pressure of the left main pump 14L and outputs the detected value to the controller 30. The same applies to the discharge pressure sensor 28R.

The operation pressure sensor 29 includes operation pressure sensors 29LA, 29LB, 29RA, 29RB, 29DL, and 29DR. The operation pressure sensor 29LA detects the contents of the operator's operation of the left operation lever 26L in the front-back direction in the form of pressure, and outputs the detected value to the controller 30. The contents of the operation are, for example, the lever operation direction and the lever operation amount (lever operation angle).

Similarly, the operation pressure sensor 29LB detects the contents of the operator's operation in the left-right direction with respect to the left operation lever 26L in the form of pressure, and outputs the detected value to the controller 30. The operation pressure sensor 29RA detects the contents of the operator's operation in the front-back direction with respect to the right operation lever 26R in the form of pressure, and outputs the detected value to the controller 30. The operation pressure sensor 29RB detects the contents of the operator's operation in the left-right direction with respect to the right operation lever 26R in the form of pressure, and outputs the detected value to the controller 30. The operation pressure sensor 29DL detects the contents of the operator's operation in the front-back direction with respect to the left traveling lever 26DL in the form of pressure, and outputs the detected value to the controller 30. The operation pressure sensor 29DR detects the contents of the operator's operation in the front-back direction with respect to the right traveling lever 26DR in the form of pressure, and outputs the detected value to the controller 30.

The controller 30 receives the output of the operation pressure sensor 29 and, if necessary, outputs a control instruction to the regulator 13 to change the discharge amount of the main pump 14. The controller 30 receives the output of the control pressure sensor 19 provided upstream of the restrictor 18 and, if necessary, outputs a control instruction to the regulator 13 to change the discharge amount of the main pump 14. The restrictor 18 includes a left restrictor 18L and a right restrictor 18R, and the control pressure sensor 19 includes a left control pressure sensor 19L and a right control pressure sensor 19R. In the left center bypass conduit line 40L, a left restrictor 18L is disposed between the control valve 176L located at the most downstream and the hydraulic fluid tank. Therefore, the flow of hydraulic fluid discharged from the left main pump 14L is restricted by the left restrictor 18L. The left restrictor 18L generates a control pressure for controlling the left regulator 13L. The left control pressure sensor 19L is a sensor configured to detect the control pressure and output the detected value to the controller 30. The controller 30 controls the discharge amount of the left main pump 14L by adjusting the swash plate inclination angle of the left main pump 14L according to the control pressure. The controller 30 decreases the discharge amount of the left main pump 14L as the control pressure is larger, and increases the discharge amount of the left main pump 14L as the control pressure is smaller. The discharge amount of the right main pump 14R is similarly controlled.

Specifically, as illustrated in FIG. 2, when the hydraulic actuators in the shovel 100 are in a standby state in which none of the hydraulic actuators are operated, the hydraulic fluid discharged from the left main pump 14L passes through the left center bypass conduit line 40L to the left restrictor 18L. The flow of hydraulic fluid discharged from the left main pump 14L increases the control pressure generated upstream of the left restrictor 18L. As a result, the controller 30 reduces the discharge amount of the left main pump 14L to the minimum allowable discharge amount, and prevents the pressure loss (pumping loss) when the hydraulic fluid discharged from the left main pump 14L passes through the left center bypass conduit line 40L. On the other hand, when any hydraulic actuator is operated, the hydraulic fluid discharged from the left main pump 14L flows into the hydraulic actuator to be operated via the control valve corresponding to the hydraulic actuator to be operated. Thus, the amount reaching the left restrictor 18L of the flow of the hydraulic fluid discharged from the left main pump 14L is reduced or eliminated, which reduces the control pressure generated upstream of the left restrictor 18L. As a result, the controller 30 increases the discharge amount of the left main pump 14L, allows sufficient hydraulic fluid to flow into the hydraulic actuator to be operated, and ensures the operation of the hydraulic actuator to be operated. The controller 30 also controls the discharge amount of the right main pump 14R in the same manner.

With the above-described configuration, the hydraulic system of FIG. 2 can prevent wasteful energy consumption with respect to the main pump 14 in the standby state. The wasteful energy consumption includes pumping losses caused by hydraulic fluid discharged by the main pump 14 in the center bypass conduit line 40. In addition, the hydraulic system of FIG. 2 can reliably supply necessary and sufficient hydraulic fluid from the main pump 14 to the hydraulic actuator to be operated when the hydraulic actuator is operated.

Next, with reference to FIGS. 3A to 3D, a configuration for operating the actuator by the machine control function of the controller 30 will be described. FIGS. 3A to 3D are views in which a part of the hydraulic system is extracted. Specifically, FIG. 3A is a view in which a part of the hydraulic system relating to the operation of the arm cylinder 8 is extracted, and FIG. 3B is a view in which a part of the hydraulic system relating to the operation of the boom cylinder 7 is extracted. FIG. 3C is a view in which a part of the hydraulic system relating to the operation of the bucket cylinder 9 is extracted, and FIG. 3D is a view in which a part of the hydraulic system relating to the operation of the turning hydraulic motor 2A is extracted.

As illustrated in FIGS. 3A to 3D, the hydraulic system includes a proportional valve 31. The proportional valve 31 includes proportional valves 31AL to 31DL, and proportional valves 31AR to 31DR.

The proportional valve 31 functions as a control valve for machine control. The proportional valve 31 is disposed in a conduit line connecting the pilot pump 15 and a pilot port of a corresponding control valve in the control valve unit 17, and is configured to change the flow path area of that conduit line. In the present embodiment, the proportional valve 31 operates in response to a control instruction output by the controller 30. Therefore, the controller 30 can supply hydraulic fluid delivered by the pilot pump 15 to the pilot port of the corresponding control valve in the control valve unit 17 via the proportional valve 31, independent of the operator's operation of the operation device 26. The controller 30 can then apply the pilot pressure generated by the proportional valve 31 to the pilot port of the corresponding control valve.

With this configuration, the controller 30 can operate the hydraulic actuator corresponding to the specific operation device 26 even when no operation is performed on the specific operation device 26. The controller 30 can forcibly stop operation of hydraulic actuators corresponding to the specific operation device 26 even when an operation is performed on the specific operation device 26.

For example, as illustrated in FIG. 3A, the left operation lever 26L is used to operate the arm 5. Specifically, the left operation lever 26L uses hydraulic fluid discharged from the pilot pump 15 to act on the pilot port of the control valve 176 with pilot pressure corresponding to the operation in the front-back direction. More specifically, the left operation lever 26L acts on the right pilot port of the control valve 176L and the left pilot port of the control valve 176R with pilot pressures corresponding to the operation amounts when operated in the arm closing direction (backward direction). Further, the left operation lever 26L acts on the left pilot port of the control valve 176L and the right pilot port of the control valve 176R with pilot pressures corresponding to the operation amounts when operated in the arm opening direction (forward direction).

The left operation lever 26L is provided with a switch NS. In the present embodiment, the switch NS is a push button switch provided at the tip of the left operation lever 26L. The operator can operate the left operation lever 26L while pressing the switch NS. The switch NS may be disposed on the right operation lever 26R or at another position in the cabin 10.

The operation pressure sensor 29LA detects the contents of the operation in the front-back direction with respect to the left operation lever 26L by the operator, and outputs the detected value to the controller 30.

A proportional valve 31AL operates in response to a control instruction (current instruction) output by the controller 30. The pilot pressure of the hydraulic fluid introduced from the pilot pump 15 to the right pilot port of the control valve 176L and the left pilot port of the control valve 176R is adjusted via the proportional valve 31AL. A proportional valve 31AR operates in response to a control instruction (current instruction) output by the controller 30. Then, the pilot pressure of the hydraulic fluid introduced into the left pilot port of the control valve 176L and the right pilot port of the control valve 176R is adjusted from the pilot pump 15 via the proportional valve 31AR. The proportional valve 31AL can adjust the pilot pressure so that the control valve 176L and the control valve 176R can be stopped at any valve position. Similarly, the proportional valve 31AR can adjust the pilot pressure so that the control valve 176L and the control valve 176R can be stopped at any valve position.

With this configuration, the controller 30 can supply the hydraulic fluid discharged from the pilot pump 15 to the right pilot port of the control valve 176L and the left pilot port of the control valve 176R via the proportional valve 31AL in response to the operator's arm closing operation. The controller 30 can also supply the hydraulic fluid discharged from the pilot pump 15 to the right pilot port of the control valve 176L and the left pilot port of the control valve 176R via the proportional valve 31AL, independently of the operator's arm closing operation. That is, the controller 30 can close the arm 5 in response to the operator's arm closing operation or independently of the operator's arm closing operation.

In response to the operator's arm opening operation, the controller 30 can supply the hydraulic fluid discharged from the pilot pump 15 to the left pilot port of the control valve 176L and the right pilot port of the control valve 176R via the proportional valve 31AR. Regardless of the operator's arm opening operation, the controller 30 can supply the hydraulic fluid discharged from the pilot pump 15 to the left pilot port of the control valve 176L and the right pilot port of the control valve 176R via the proportional valve 31AR. That is, the controller 30 can open the arm 5 in response to the operator's arm opening operation or independently of the operator's arm opening operation.

With this configuration, the controller 30 can reduce the pilot pressure acting on the closed pilot port of the control valve 176 (the left pilot port of the control valve 176L and the right pilot port of the control valve 176R), and forcibly stop the closing operation of the arm 5, if necessary, even when the operator is performing the arm closing operation. The same applies to the case of forcibly stopping the opening operation of the arm 5 when the operator is performing the arm opening operation.

Alternatively, the controller 30 may, if necessary, control the proportional valve 31AR, increase the pilot pressure acting on the open pilot port of the control valve 176 (the right pilot port of the control valve 176L and the left pilot port of the control valve 176R) opposite the closed pilot port of the control valve 176, and forcibly return the control valve 176 to the neutral position to forcibly stop the closing operation of the arm 5, even when an operator is performing an arm closing operation. The same applies to a case of forcibly stopping the opening operation of the arm 5 when an operator is performing an arm opening operation.

The same applies to a case of forcibly stopping the operation of the boom 4 when a boom raising operation or a boom lowering operation is performed by the operator, a case of forcibly stopping the operation of the bucket 6 when a bucket closing operation or a bucket opening operation is performed by the operator, and a case of forcibly stopping the turning operation of the upper turning body 3 when the turning operation is performed by the operator, although the illustration with reference to FIGS. 3B to 3D below is omitted. The same applies to a case of forcibly stopping a traveling operation of the lower traveling body 1 when the traveling operation is performed by the operator.

As illustrated in FIG. 3B, the right operation lever 26R is used to operate the boom 4. Specifically, the right operation lever 26R utilizes the hydraulic fluid discharged from the pilot pump 15, and causes the pilot pressure corresponding to the operation in the front-back direction to act on the pilot port of the control valve 175. More specifically, the right operation lever 26R causes the pilot pressure corresponding to the operation amount to act on the right pilot port of the control valve 175L and the left pilot port of the control valve 175R when operated in the boom raising direction (backward direction). When the right operation lever 26R is operated in the boom lowering direction (forward direction), the pilot pressure corresponding to the operation amount acts on the right pilot port of the control valve 175R.

The operation pressure sensor 29RA detects the contents of the operation in the front-back direction of the right operation lever 26R by the operator, and outputs the detected value to the controller 30.

A proportional valve 31BL operates in response to a control instruction (current instruction) output by the controller 30. Then, the pilot pressure by the hydraulic fluid introduced into the right pilot port of the control valve 175L and the left pilot port of the control valve 175R is adjusted from the pilot pump 15 via the proportional valve 31BL. A proportional valve 31BR operates in response to a control instruction (current instruction) output by the controller 30. Then, the pilot pressure due to hydraulic fluid introduced from the pilot pump 15 to the right pilot port of the control valve 175R via the proportional valve 31BR is adjusted. The proportional valve 31BL can adjust the pilot pressure so that the control valve 175L and the control valve 175R can be stopped at any valve position. The proportional valve 31BR can adjust the pilot pressure so that the control valve 175R can be stopped at any valve position.

With this configuration, the controller 30 can supply the hydraulic fluid discharged from the pilot pump 15 to the right pilot port of the control valve 175L and the left pilot port of the control valve 175R via the proportional valve 31BL in response to the boom raising operation by the operator. The controller 30 can also supply the hydraulic fluid discharged from the pilot pump 15 to the right pilot port of the control valve 175L and the left pilot port of the control valve 175R via the proportional valve 31BL independently of the boom raising operation by the operator. That is, the controller 30 can raise the boom 4 in response to the boom raising operation by the operator or independently of the boom raising operation by the operator.

In addition, the controller 30 can supply the hydraulic fluid discharged from the pilot pump 15 to the right pilot port of the control valve 175R via the proportional valve 31BR in response to the operator's boom lowering operation. In addition, the controller 30 can supply the hydraulic fluid discharged from the pilot pump 15 to the right pilot port of the control valve 175R via the proportional valve 31BR independently of the operator's boom lowering operation. That is, the controller 30 can lower the boom 4 in response to the operator's boom lowering operation or independently of the operator's boom lowering operation.

As illustrated in FIG. 3C, the right operation lever 26R is also used to operate the bucket 6. Specifically, the right operation lever 26R utilizes the hydraulic fluid discharged from the pilot pump 15 to cause the pilot pressure corresponding to the operation in the left-right direction to act on the pilot port of the control valve 174. More specifically, when operated in the bucket closing direction (left direction), the right operation lever 26R causes the pilot pressure corresponding to the operation amount to act on the left pilot port of the control valve 174. When operated in the bucket opening direction (right direction), the right operation lever 26R causes the pilot pressure corresponding to the operation amount to act on the right pilot port of the control valve 174.

The operation pressure sensor 29RB detects the contents of the operation by the operator in the right-left direction with respect to the right operation lever 26R, and outputs the detected value to the controller 30.

A proportional valve 31CL operates in response to a control instruction (current instruction) output by the controller 30. Then, the pilot pressure by the hydraulic fluid introduced from the pilot pump 15 to the left pilot port of the control valve 174 via the proportional valve 31CL is adjusted. A proportional valve 31CR operates in response to a control instruction (current instruction) output by the controller 30. The pilot pressure due to hydraulic fluid introduced from the pilot pump 15 to the right pilot port of the control valve 174 via the proportional valve 31CR is adjusted. The proportional valve 31CL can adjust the pilot pressure to stop the control valve 174 at any valve position. Similarly, the proportional valve 31CR can adjust the pilot pressure to stop the control valve 174 at any valve position.

With this configuration, the controller 30 can supply the hydraulic fluid discharged by the pilot pump 15 to the left pilot port of the control valve 174 via the proportional valve 31CL in response to the operator's bucket closing operation. The controller 30 can also supply the hydraulic fluid discharged by the pilot pump 15 to the left pilot port of the control valve 174 via the proportional valve 31CL independently of the operator's bucket closing operation. That is, the controller 30 can close the bucket 6 in response to the operator's bucket closing operation or independently of the operator's bucket closing operation.

The controller 30 can also supply the hydraulic fluid discharged by the pilot pump 15 to the right pilot port of the control valve 174 via the proportional valve 31CR in response to the operator's bucket opening operation. The controller 30 can also supply the hydraulic fluid discharged by the pilot pump 15 to the right pilot port of the control valve 174 via the proportional valve 31CR independently of the operator's bucket opening operation. That is, the controller 30 can open the bucket 6 in response to the operator's bucket opening operation or independently of the operator's bucket opening operation.

As illustrated in FIG. 3D, the left operation lever 26L is also used to operate the turning mechanism 2. Specifically, the left operation lever 26L uses hydraulic fluid discharged from the pilot pump 15 to act on the pilot port of the control valve 173 with pilot pressure corresponding to operation in the left-right direction. More specifically, when operated in the left turning direction (left direction), the left operation lever 26L acts on the left pilot port of the control valve 173 with pilot pressure corresponding to the operation amount. When operated in the right turning direction (right direction), the left operation lever 26L acts on the right pilot port of the control valve 173 with pilot pressure corresponding to the operation amount.

The operation pressure sensor 29LB detects the contents of the operation in the left-right direction with respect to the left operation lever 26L by the operator, and outputs the detected value to the controller 30.

A proportional valve 31DL operates in response to a control instruction (current instruction) output by the controller 30. Then, the pilot pressure by the hydraulic fluid introduced from the pilot pump 15 to the left pilot port of the control valve 173 via the proportional valve 31DL is adjusted. A proportional valve 31DR operates in response to a control instruction (current instruction) output by the controller 30. The pilot pressure due to hydraulic fluid introduced from the pilot pump 15 to the right pilot port of the control valve 173 via the proportional valve 31DR is adjusted. The proportional valve 31DL can adjust the pilot pressure so that the control valve 173 can be stopped at any valve position. Similarly, the proportional valve 31DR can adjust the pilot pressure so that the control valve 173 can be stopped at any valve position.

With this configuration, the controller 30 can supply the hydraulic fluid discharged by the pilot pump 15 to the left pilot port of the control valve 173 via the proportional valve 31DL in response to the operator's left turning operation. The controller 30 can also supply the hydraulic fluid discharged by the pilot pump 15 to the left pilot port of the control valve 173 via the proportional valve 31DL independently of the operator's left turning operation. That is, the controller 30 can make the turning mechanism 2 turn left in response to the operator's left turning operation or independently of the operator's left turning operation.

In addition, the controller 30 can supply the hydraulic fluid discharged from the pilot pump 15 to the right pilot port of the control valve 173 via the proportional valve 31DR in response to the operator's right turning operation. Also, the controller 30 can supply the hydraulic fluid discharged by the pilot pump 15 to the right pilot port of the control valve 173 via the proportional valve 31DR independently of the operator's right turning operation. That is, the controller 30 can make the turning mechanism 2 turn right in response to the operator's right turning operation or independently of the operator's right turning operation.

The shovel 100 may be configured to automatically move the lower traveling body 1 forward and backward. In this case, the hydraulic system portion relating to the operation of the left traveling hydraulic motor 2ML and the hydraulic system portion relating to the operation of the right traveling hydraulic motor 2MR may be configured in the same manner as the hydraulic system portion relating to the operation of the boom cylinder 7.

Although the description of the electric operation lever has been described as a form of the operation device 26, a hydraulic operation lever may be used instead of the electric operation lever. In such a case, the lever operation amount of the hydraulic operation lever may be detected in the form of pressure by a pressure sensor and input to the controller 30. A solenoid valve may be disposed between the operation device 26 as the hydraulic operation lever and the pilot port of each control valve. The solenoid valve is configured to operate in response to an electrical signal from the controller 30. With this configuration, when a manual operation using the operation device 26 as a hydraulic operation lever is performed, the operation device 26 can move each control valve by increasing or decreasing the pilot pressure according to the lever operation amount. Further, each control valve may be composed of a solenoid spool valve. In this case, the solenoid spool valve operates in response to an electric signal from the controller 30 corresponding to the lever operation amount of the electric operation lever. Next, the functions of the controller 30 will be described with reference to FIG. 4. FIG. 4 is a functional block diagram of the controller 30. In the example of FIG. 4, the controller 30 is configured to receive signals output from an attitude detection device, the operation device 26, the object detection device 70, the imaging device 80, the switch NS, etc., perform various operations, and output control instructions to the proportional valve 31, the display device D1, the sound output device D2, etc. The attitude detection device includes, for example, a boom angle sensor S1, an arm angle sensor S2, a bucket angle sensor S3, a body inclination sensor S4, and a turning angular velocity sensor S5. The controller 30 has a trajectory generation part and an autonomous control part 30B as functional blocks. Each functional block may be composed of hardware or software.

The trajectory generation part 30A is configured to generate a target trajectory which is a trajectory plotted by a predetermined part of the shovel 100 when the shovel 100 is operated autonomously. The predetermined part is, for example, a claw end of the bucket 6 or a predetermined point on the back surface of the bucket 6. In the present embodiment, the trajectory generation part 30A generates a target trajectory that the autonomous control part 30B uses to autonomously operate the shovel 100. Specifically, the trajectory generation part 30A generates a target trajectory based on an output of at least one of the object detection device 70 and the imaging device 80.

The autonomous control part 30B is configured to operate the shovel 100 autonomously. In the present embodiment, the autonomous control part 30B is configured to move a predetermined part of the shovel 100 along a target trajectory generated by the trajectory generation part 30A when a predetermined start condition is satisfied. Specifically, the autonomous control part 30B autonomously operates the shovel 100 so that the predetermined part of the shovel 100 moves along the target trajectory when the operation device 26 is operated while the switch NS is pressed. For example, the autonomous control part 30B autonomously operates the excavation attachment AT so that the claw end of the bucket 6 moves along the target trajectory when the left operation lever 26L is operated in the arm opening direction while the switch NS is pressed. The autonomous control part 30B may operate the shovel 100 autonomously so that the predetermined part of the shovel 100 moves along the target trajectory when the switch NS is pressed, regardless of whether the operation device 26 is operated.

Next, with reference to FIGS. 5 and 6, an example of a function (hereinafter referred to as “autonomous control function”) in which the controller 30 autonomously controls the movement of the attachment will be described. FIGS. 5 and 6 are block diagrams illustrating the autonomous control function.

First, as illustrated in FIG. 5, the controller 30 determines the target movement speed and the target movement direction based on the operation inclination. The operation inclination is determined based on, for example, the lever operation amount. A target moving velocity is a target value of the moving velocity of a control reference point, and a target moving direction is a target value of a moving direction of the control reference point. The control reference point is, for example, a claw end of the bucket 6 or a predetermined point on the back surface of the bucket 6. The control reference point is calculated based on, for example, the boom angle β₁, the arm angle the bucket angle β₃, and the turning angle α₁.

Thereafter, the controller 30 calculates three-dimensional coordinates (Xer, Yer, Zer) of the control reference point after the unit time has elapsed, based on the target moving velocity, the target moving direction, and three-dimensional coordinates (Xe, Ye, Ze) of the control reference point. The three-dimensional coordinates (Xer, Yer, Zer) of the control reference point after the unit time has elapsed are, for example, coordinates on the target trajectory. The unit time is, for example, the time equivalent to an integer multiple of the control period. The target trajectory may be, for example, target trajectory relating to a backfilling operation performed for a backfilling work, which is a work for backfilling a hole. The backfilling operation includes an operation of releasing a sediment as an example of a mass of earth and sand put in the bucket 6 into the hole, and an operation of pushing a sediment placed around the hole with the bucket 6 into the hole. Typically, the backfilling operation is a combined operation including the bucket opening operation and the arm opening operation. In this case, the target trajectory may be calculated based on at least one of, for example, the shape of the hole opening, the depth of the hole, the volume of the sediment already released into the hole, and the volume of the sediment put into the bucket 6. The shape of the hole, the depth of the hole, the volume of sediment already released into the hole, and the volume of the sediment put into the bucket 6 may be derived based on, for example, an output of at least one of the object detection device 70 and the imaging device 80. For example, the target trajectory may be set so that the variation in depth of each part of the hole is not significantly large. That is, the target trajectory may be set so that only a part of the hole is not intensively backfilled. Conversely, the target trajectory may be set so that only a part of the hole is intensively backfilled.

The target trajectory is typically calculated before the backfilling operation starts, and is not changed until the backfilling operation ends. However, the target trajectory may be changed during the execution of the backfilling operation. That is, a content of the backfilling operation may be changed.

Thereafter, the controller 30 generates instruction values β_1r, β_2r, and β_3r relating to the rotations of the boom 4, the arm 5, and the bucket 6, and an instruction value air relating to the turning of the upper turning body 3, based on the calculated three-dimensional coordinates (Xer, Yer, Zer). The instruction value β_1r represents, for example, the boom angle β₁ when the control reference point can be adjusted to the three-dimensional coordinates (Xer, Yer, Zer). Similarly, the instruction value β_2r represents an arm angle β₂ when the control reference point can be adjusted to the three-dimensional coordinates (Xer, Yer, Zer), the instruction value β_3r represents a bucket angle β₃ when the control reference point can be adjusted to the three-dimensional coordinates (Xer, Yer, Zer), and the instruction value air represents a turning angle α₁ when the control reference point can be adjusted to the three-dimensional coordinates (Xer, Yer, Zer).

The instruction value β_3r for the rotation of the bucket 6 may be changed during the execution of the backfilling operation. For example, the instruction value β_3r may be adjusted smaller when the depth of the hole in the backfilled portion becomes shallower than the desired depth. That is, the instruction value β_3r is typically controlled by open-loop control, but may be feedback controlled according to the depth of the hole in the backfilled portion. Thereafter, as illustrated in FIG. 6, the controller 30 operates the boom cylinder 7, the arm cylinder 8, the bucket cylinder 9, and the turning hydraulic motor 2A so that the boom angle β₁, the arm angle β₂, the bucket angle β₃, and the turning angle α₁ have the generated instruction values β_1r, β_2r, β_3r, and α_1r, respectively. The turning angle α₁ is calculated based on an output of the turning angular velocity sensor S5, for example.

Specifically, the controller 30 generates a boom cylinder pilot pressure instruction corresponding to the difference Δβ₁ between a current value and the instruction value β_1r of the boom angle β₁. A control current corresponding to the boom cylinder pilot pressure instruction is output to a boom control mechanism 31B. The boom control mechanism 31B is configured so that a pilot pressure in response to a control current corresponding to the boom cylinder pilot pressure instruction can be applied to the control valve 175 as a boom control valve. The boom control mechanism 31B may be, for example, the proportional valve 31BL and the proportional valve 31BR in FIG. 3B.

Thereafter, the control valve 175 that has received the pilot pressure generated by the boom control mechanism 31B causes the hydraulic fluid discharged from the main pump 14 to flow into the boom cylinder 7 in the flow direction and flow rate corresponding to the pilot pressure.

At this time, the controller 30 may generate a boom spool control instruction based on a displacement amount of the spool of the control valve 175 detected by the boom spool displacement sensor S7. The boom spool displacement sensor S7 is a sensor configured to detect the displacement amount of a spool constituting the control valve 175. The controller 30 may output a control current corresponding to the boom spool control instruction to the boom control mechanism 31B. In this case, the boom control mechanism 31B applies a pilot pressure in response to the control current corresponding to the boom spool control instruction to the control valve 175.

The boom cylinder 7 extends and retracts by hydraulic fluid supplied via the control valve 175. The boom angle sensor S1 detects the boom angle β₁ of the boom 4 moved by extending and retracting the boom cylinder 7.

Thereafter, the controller 30 feeds back the boom angle β₁ detected by the boom angle sensor S1 as a current value of the boom angle β₁ used in generating the boom cylinder pilot pressure instruction.

Although the above description relates to the operation of the boom 4 based on the instruction value β_1r, the same applies to the operation of the arm 5 based on the instruction value β_2r, the operation of the bucket 6 based on the instruction value β_3r, and the turning operation of the upper turning body 3 based on the instruction value air. An arm control mechanism 31A is configured so that a pilot pressure in response to a control current corresponding to an arm cylinder pilot pressure instruction can be applied to the control valve 176 as an arm control valve. The arm control mechanism 31A may be, for example, the proportional valve 31AL and the proportional valve 31AR in FIG. 3A. A bucket control mechanism 31C is configured so that a pilot pressure in response to a control current corresponding to a bucket cylinder pilot pressure instruction can be applied to the control valve 174 as a bucket control valve. The bucket control mechanism 31C may be, for example, the proportional valve 31CL and the proportional valve 31CR in FIG. 3C. A turning control mechanism 31D is configured so that a pilot pressure in response to a control current corresponding to a turning hydraulic motor pilot pressure instruction can be applied to the control valve 173 as a turning control valve. The turning control mechanism 31D may be, for example, the proportional valve 31DL and the proportional valve 31DR in FIG. 3D. An arm spool displacement sensor S8 is a sensor configured to detect the displacement amount of a spool constituting the control valve 176, a bucket spool displacement sensor S9 is a sensor configured to detect a displacement amount of a spool constituting the control valve 174, and a turning spool displacement sensor S6 is a sensor configured to detect a displacement amount of a spool constituting the control valve 173.

As illustrated in FIG. 5, the controller 30 may derive pump discharge amounts from the instruction values β_1r, β_2r, β_3r, and air using the pump discharge amount deriving parts CP1, CP2, CP3, and CP4. In the present embodiment, the pump discharge amount deriving parts CP1, CP2, CP3, and CP4 derive the pump discharge amounts from the instruction values β_1r, β_2r, β_3r, and air using a pre-registered reference table or the like. The pump discharge amounts derived by the pump discharge amount deriving parts CP1, CP2, CP3, and CP4 are summed and input to a pump flow calculation part as a total pump discharge amount. The pump flow calculation part controls the discharge amount of the main pump 14 based on the input total pump discharge amount. In the present embodiment, the pump flow calculation part controls the discharge amount of the main pump 14 by changing a swash plate inclination angle of the main pump 14 according to the total pump discharge amount.

Thus, the controller 30 can perform control of respective openings of the control valve 175 as the boom control valve, the control valve 176 as the arm control valve, the control valve 174 as the bucket control valve, and the control valve 173 as the turning control valve, simultaneously with performing control of the discharge amount of the main pump 14. Therefore, the controller 30 can supply an appropriate amount of hydraulic fluid to each of the boom cylinder 7, the arm cylinder 8, the bucket cylinder 9, and the turning hydraulic motor 2A.

The controller 30 calculates three-dimensional coordinates (Xer, Yer, Zer), generates instruction values β_1r, β_2r, β_3r, and α_1r, and determines a discharge amount of the main pump 14 as one control cycle, and repeats this control cycle to execute autonomous control. The controller can improve the accuracy of autonomous control by feedback controlling the control reference point based on the respective outputs of the boom angle sensor S1, the arm angle sensor S2, the bucket angle sensor S3, and the turning angular velocity sensor S5. Specifically, the controller 30 can improve the accuracy of autonomous control by feedback controlling the flow rates of hydraulic fluid flowing into the boom cylinder 7, the arm cylinder 8, the bucket cylinder 9, and the turning hydraulic motor 2A.

Further, the controller 30 may be configured to monitor the distance between the bucket 6 and the surrounding obstacles so that the bucket 6 does not come into contact with the surrounding obstacles when performing autonomous control for the backfilling operation. For example, the controller 30 may stop the movement of the excavation attachment AT when determining that the distance between one or each of a plurality of predetermined points in the bucket 6 and the surrounding obstacles falls below a predetermined value based on the outputs of the attitude detection device and the object detection device 70.

Next, with reference to FIGS. 7A to 7C and FIGS. 8A to 8C, an example of autonomous control for the backfilling operation will be described. FIGS. 7A to 7C are top views illustrating the shovel 100 performing the backfilling operation and a hole HL subject to the backfilling operation. FIGS. 8A to 8C are cross-sectional views illustrating the hole HL. The controller 30 recognizes a position of the hole HL as an object subject to the backfilling operation (the position to be backfilled) and generates a target trajectory from the sediment pile (an excavation completion position) to the hole HL.

The excavation completion position may be set to the position of the bucket 6 when the sediment is put into the bucket 6. Alternatively, the excavation completion position may be set to the position of the bucket 6 when the bucket 6 is lifted by a predetermined height from the position of the bucket 6 when the sediment is put into the bucket 6.

The controller 30 may recognize the shape (opening area, depth, etc.) of the hole HL or a position of the hole HL based on the output of the object detection device 70, and set a target position relating to the backfilling operation. The controller 30 may recognize the uneven shape of a landform based on the output of the object detection device 70, and display the recognized uneven shape on the display device D1. In this case, the controller 30 may display a frame or marker or the like on the image of the hole HL or the uneven shape or the like (hereinafter referred to as “hole HL or the like”) displayed on the display device D1 so that the operator of the shovel 100 can recognize the hole HL or the like. The image of the hole HL or the like is included in the captured image output from the imaging device (object detection device 70). Then, the controller 30 can set a target position for the hole HL or the like by setting input (selection) of the hole HL or the like to be recognized by the operator. The operator may select an image of the hole HL or the like to be backfilled from the captured image displayed on the display device D1, and set the selected image as a target position. In this case, the actual position in a landform region displayed on the display device D1 is associated with the position of the image in a display region of the display device D1. Therefore, by the operator selecting a predetermined position in the display region of the display device D1, the controller 30 can recognize the actual position of the hole HL relative to the shovel 100 and set the target position for backfilling.

In this manner, the controller 30 generates a trajectory up to the set target position as the target trajectory. Typically, the target position is set above the bottom of the hole HL. The target position is also typically set inside the contour of the hole HL.

Specifically, FIGS. 7A and 8A illustrate a state when a first backfilling operation by autonomous control is completed. A shovel figure represented by the broken line in FIG. 7A illustrates a state of the shovel 100 after the first excavation operation by manual operation is completed and before the first backfilling operation is started. A sediment R1 represents a sediment released into the hole HL by the first backfilling operation. The sediment R1 is released into a portion of the hole HL farthest from the shovel 100, for example. In the state illustrated in FIGS. 7A and 8A, the controller 30 generates a target trajectory between the positions of the sediment pile and the farthest portion of the hole HL. The controller 30 may change the target position at each backfilling operation. As a result, the target position and the target trajectory at the second or third backfilling operation are changed. The target position and the timing for the change of the target trajectory may be changed according to the shape (size or depth, etc.) of the hole HL.

FIGS. 7B and 8B illustrate a state when a second backfilling operation by autonomous control is completed. The shovel figure represented by the broken line in FIG. 7B represents a state of the shovel 100 after the second excavation operation by manual operation is completed and before the second backfilling operation is started. A sediment R2 represents a sediment released into the hole HL by the second backfilling operation. The sediment R2 is released into a portion of the hole HL closer to the shovel 100 than the sediment R1, for example, so as to be adjacent to the sediment R1. In the state illustrated in FIGS. 7B and 8B, the controller 30 updates the target trajectory generated in the state illustrated in FIGS. 7A and 8A.

FIGS. 7C and 8C illustrate the state when a third backfilling operation by autonomous control is completed. The shovel figure represented by the broken line in FIG. 7C represents a state of the shovel 100 after a third excavation operation by manual operation is completed and before the third backfilling operation is started. A sediment R3 represents a sediment released into the hole HL by the third backfilling operation. The sediment R3 is, for example, released to a portion of the hole HL closer to the shovel 100 than the sediment R2 so as to be adjacent to the sediment R2. In the state illustrated in FIGS. 7C and 8C, the controller 30 updates the target trajectory that has been updated in the state illustrated in FIGS. 7B and 8B. Note that the controller 30 may recognize the shape of the sediment dropped into the hole HL based on the output from the imaging device 80 (object detection device 70). For example, the controller 30 may estimate the shape of the sediment dropped into the hole HL based on the shape of the hole HL, the sediment characteristics, the dropped position, and the like. Thus, the controller 30 can change the target position in the next backfilling operation by identifying the shape of the sediment dropped into the hole HL.

The operator of the shovel 100 executes the first backfilling operation by autonomous control by pressing the switch NS at the time before starting the first backfilling operation, i.e., when the state of the shovel 100 is set to the state indicated by the broken line in FIG. 7A. In the example illustrated in FIGS. 7A to 7C and FIGS. 8A to 8C, the shovel 100 is configured to execute the backfilling operation when the switch NS is pressed, but the shovel 100 may be configured to execute the backfilling operation when the left operation lever 26L is operated in the right turning direction while the switch NS is pressed.

In the example illustrated in FIG. 7A, the target trajectory for the first backfilling operation is generated based on a current claw end position AP1 of the bucket 6 and a claw end position BP1 of the bucket 6 when the first backfilling operation is completed. The position BP1 is set such that, for example, the claw end of the bucket 6 is positioned directly above the center point of the sediment R1. The sediment R1 is a sediment to be put into the hole HL by the first backfilling operation.

Thereafter, the controller 30 executes the first backfilling operation by autonomous control using the calculated target trajectory. Specifically, the controller automatically turns the upper turning body 3 to the right to automatically expand and contract the excavation attachment AT so that the trajectory plotted by the claw end of the bucket 6 follows the target trajectory.

After the first backfilling operation by autonomous control is completed, the operator of the shovel 100 performs an intermediate operation including a manually operated left-turning operation to bring the bucket 6 closer to a sediment pile F1 illustrated in FIG. 7A. This intermediate operation for moving the claw end of the bucket 6 from the position when the backfilling operation is completed to the position when the next excavation operation is started may be performed autonomously without the operator's manual operation and may be performed semi-autonomously to assist the operator's manual operation. When this intermediate operation is performed autonomously, a target trajectory for this intermediate operation is generated based on a current claw end position BP1 of the bucket 6 and a claw end position DP1 of the bucket 6 at the start of the second excavation operation. For example, the position DP1 is set to be located directly above the center point of the sediment pile F1. The semi-autonomous operation differs from the autonomous operation in that the semi-autonomous operation is executed in response to the manual operation of the operation lever by the operator, but the semi-autonomous operation is common to the autonomous operation in that the claw end of the bucket 6 is moved along the target trajectory.

Thereafter, the operator puts the sediment constituting the sediment pile F1 into the bucket 6 by a manually operated excavation operation. Thereafter, the operator executes the second backfilling operation by autonomous control by pressing the switch NS at a time after the excavation operation is finished, that is, when the state of the shovel 100 is set to the state indicated by the broken line in FIG. 7B.

In the example illustrated in FIG. 7B, the target trajectory for the second backfilling operation is generated based on a current claw end position AP2 of the bucket 6 and a claw end position BP2 of the bucket 6 when the second backfilling operation is completed. The position BP2 is set such that, for example, the claw end of the bucket 6 is positioned directly above the center point of the sediment R2. The sediment R2 is a sediment to be put into the hole HL by the second backfilling operation.

Thereafter, the controller 30 executes the second backfilling operation by autonomous control using the calculated target trajectory. Specifically, the controller automatically right-turns the upper turning body 3 and automatically extends and retracts the excavation attachment AT so that the trajectory plotted by the claw end of the bucket 6 follows the target trajectory.

After the second backfilling operation by autonomous control is completed, the operator of the shovel 100 performs an intermediate operation including a manually operated left-turning operation to bring the bucket 6 closer to a sediment pile F2 illustrated in FIG. 7B. This intermediate operation may be performed autonomously without the operator's manual operation and may be performed semi-autonomously to assist the operator's manual operation. When this intermediate operation is performed autonomously, a target trajectory for this intermediate operation is generated based on a current claw end position BP2 of the bucket 6 and a claw end position DP2 of the bucket 6 at the start of the third excavation operation. The position DP2 is set to be located directly above the center point of the sediment pile F2, for example.

Then, the operator puts a sediment constituting the sediment pile F2 into the bucket 6 by manually operated excavation operation. Then, the operator executes the third backfilling operation by autonomous control by pressing the switch NS at a time after the excavation operation is finished, that is, when the state of the shovel 100 is set to the state indicated by the broken line in FIG. 7C.

In this manner, the controller 30 can reduce the operator's burden on the manual backfilling operation by executing the backfilling operation autonomously. In the above-described embodiment, the intermediate operation and the excavation operation are executed in response to the operator's manual operation; however, at least one of the intermediate operation and the excavation operation may be executed autonomously or semi-autonomously by the controller in the same manner as the backfilling operation.

Referring to FIGS. 9A and 9B, an example of a leveling operation performed after the hole HL is backfilled will be described. FIGS. 9A and 9B are cross-sectional views illustrating the backfilled hole HL, which correspond to FIGS. 8A to 8C. Specifically, FIGS. 9A and 9B illustrate a state of the sediment backfilled into the hole HL by a plurality of backfilling operations. More specifically, FIG. 9A illustrates a state of the sediment in the hole HL before the leveling operation is performed, and FIG. 9B illustrates a state of the sediment in the hole HL after the leveling operation is performed. In FIGS. 9A and 9B, for clarity, the ground around the hole HL is marked with a shaded pattern, and the sediment backfilled in the hole HL is marked with a dot pattern.

In the present embodiment, the controller 30 is configured to set the height of a target surface TS before the backfilling operation is performed. The target surface TS is a virtual surface corresponding to the ground formed when a hole HL to be backfilled is backfilled with a sediment, and is typically a virtual horizontal plane. The controller detects, for example, the hole HL and a surrounding surface CS, which is the ground around the hole HL, based on the output of the object detection device 70. The controller sets a height of the target surface TS based on a height of the detected surrounding surface CS. The height of the target surface TS is typically set to be the same as the height of the surrounding surface CS. Respective dashed one-dotted lines illustrated in FIGS. 9A and 9B represent the target surface TS.

The controller 30 then determines, for example, whether the hole HL has been backfilled with the sediment based on the output of the object detection device 70. In the example illustrated in FIGS. 9A and 9B, the controller determines that the hole HL has been backfilled with the sediment when the entire target surface TS has been backfilled with the sediment. The controller 30 then executes an autonomous leveling operation when determining that the hole HL has been backfilled with the sediment. The backfilling operation executed prior to the leveling operation is executed so that the height of the sediment backfilled in the hole HL is slightly higher than the height of the target surface TS.

When determining that the hole HL has been backfilled with the sediment, the controller 30 generates a target trajectory along the target surface TS, and performs a leveling operation by automatically moving the claw end of the bucket 6 in a direction away from the shovel 100 along the target trajectory. In this case, the leveling operation is a combined operation including an arm opening operation. FIG. 9A illustrates a position of the bucket 6 when the leveling operation is started, and FIG. 9B illustrates a position of the bucket 6 when the leveling operation is completed. The controller 30 may set the target surface TS based on the height of the landform adjacent to the hole HL. Alternatively, the controller 30 may set the target surface TS based on the height of the sediment backfilled in the hole HL or the sediment shape. Alternatively, the controller may set the target surface TS based on the construction plan (design data).

This configuration enables the controller 30 to level a surface of the sediment backfilled in the hole HL so that the surface of the sediment backfilled in the hole HL has no irregularities. Also, this configuration enables the controller 30 to make the height of the surface of the sediment backfilled in the hole HL and the height of the surrounding surface CS substantially the same.

Next, referring now to FIGS. 10A and 10B, another example of autonomous control for the backfilling operation will be described. FIG. 10A is a top view illustrating the shovel 100 when the backfilling operation is performed and the hole HL subject to the backfilling operation, which corresponds to FIGS. 7A to 7C. FIG. 10B is a cross-sectional view illustrating the hole HL, which corresponds to FIGS. 8A to 8C.

In the example illustrated in FIGS. 10A and 10B, the controller 30 is configured to push a sediment into the hole HL by pushing it off with the bucket 6 without lifting the sediment with the bucket 6 when the sediment to be backfilled into the hole HL is within a predetermined distance range from the hole HL. In the example illustrated in FIGS. 10A and 10B, the controller 30 uses a back face BF of the bucket 6 to autonomously perform a push-off operation to push off a sediment constituting a sediment pile F10 within the predetermined distance range from the hole HL into the hole HL. In FIG. 10A, the predetermined distance range is a range Z1 surrounded by a broken line.

Specifically, as illustrated in FIG. 10B, the controller 30 autonomously operates the excavation attachment AT so as to push the sediment constituting the sediment pile F10 into the hole HL by two backfilling operations (push-off operations).

For example, the controller 30 recognizes a position and a shape of the sediment pile F10 based on the output of the object detection device 70. Based on the recognized position and shape of the sediment pile F10, the controller 30 generates a target trajectory TL for pushing the sediment constituting the sediment pile F10 into the hole HL. At this time, the controller 30 may calculate the volume or weight of the sediment constituting the sediment pile F10. There is a limit on the volume or weight of the sediment that can be pushed off by a single push-off operation, so that the target trajectory can be generated so as not to exceed this limit.

FIG. 10B illustrates a target trajectory TL1, which is a part of the target trajectory TL for the first push-off operation, as a dashed one-dotted line, and a target trajectory TL2, which is a part of the target trajectory TL for the second push-off operation, as a dashed-two dotted line. FIGS. 10A and 10B illustrate a state of the bucket 6 when the first push-off operation is completed as a solid line, and a state of the bucket 6 when the first push-off operation is started as a bucket FIG. 6A plotted with a broken line. Further, FIG. 10B illustrates a sediment F10T pushed into the hole HL by the first push-off operation out of the sediment pile F10 as a solid line, and a portion F10T1 corresponding to the sediment F10T of the sediment pile F10 before the first push-off operation is started as a broken line.

A sediment F10B, which remains even after the first push-off operation among the sediments constituting the sediment pile F10, is pushed into the hole HL by the second push-off operation, that is, by moving the claw end of the bucket 6 from the side close to the shovel 100 to the far side along the target trajectory TL2.

By executing the push-off operation as described above, the controller 30 can push the sediment relatively close to the hole HL into the hole HL. In the example described above, the controller 30 is configured to execute the push-off operation for dropping a sediment into the hole HL using the back face BF of the bucket 6, but may be configured to execute a push-off operation for dropping a sediment into the hole HL using a front face or a side face of the bucket 6. For example, the controller 30 may be configured to execute the push-off operation for dropping a sediment into the hole HL using the front face of the bucket 6 when dropping the sediment constituting a sediment pile F11 on the +X side (side far from the shovel 100) of the hole HL in the range Z1.

The controller 30 may also be configured to release a sediment, which has been put into the bucket 6 and lifted by the excavation operation, into the hole HL as described with reference to FIGS. 7A to 7C and FIGS. 8A to 8C when the sediment to be backfilled into the hole HL is outside the predetermined distance range from the hole HL. Specifically, with respect to a sediment pile F12 outside the range Z1, the controller 30 may be configured to release a sediment constituting the sediment pile F12, which has been put into the bucket 6 and lifted by the excavation operation, into the hole HL by an autonomous backfilling operation.

In the example illustrated in FIGS. 10A and 10B, the controller 30 may be configured to perform the push-off operation when the switch NS is pressed, but may be configured to perform the push-off operation when the left operation lever 26L is operated in the arm opening direction while the switch NS is pressed.

Next, with reference to FIG. 11, a backfilling operation (push-off operation) for dropping the sediment into the hole HL using the side face of the bucket 6 will be described. FIG. 11 is a top view illustrating the shovel 100 when the backfilling operation (push-off operation) is performed and the hole HL subject to the backfilling operation (push-off operation), which corresponds to FIG.

In the example illustrated in FIG. 11, the controller 30 is configured to push the sediment into the hole HL by pushing off the sediment with the bucket 6, without lifting the sediment with the bucket 6, when the sediment to be backfilled in the hole HL is within a predetermined distance range from the hole HL, as in the example illustrated in FIGS. 10A and 10B. When the sediment to be backfilled in the hole HL is outside the predetermined distance range from the hole HL, the controller 30 is configured to put the sediment into the bucket 6 and lift the sediment in the bucket 6 by the excavation operation, and then release the sediment put in the bucket 6 into the hole HL, as described with reference to FIGS. 7A to 7C and FIGS. 8A to 8C.

In the example illustrated in FIG. 11, the controller 30 uses a side face SF (left-side face LSF) of the bucket 6 to autonomously execute a push-off operation to push a sediment constituting a sediment pile F13 within a predetermined distance range from the hole HL into the hole HL. In FIG. 11, the predetermined distance range is a range Z1 surrounded by a broken line.

Specifically, as illustrated in FIG. 11, the controller 30 is configured to autonomously turn the upper turning body 3 to the left so as to push the sediment constituting the sediment pile F13 into the hole HL by two backfilling operations (push-off operations).

For example, the controller 30 recognizes a position and a shape of the sediment pile F13 based on the output of the object detection device 70. Then, the controller 30 generates a target trajectory TL for pushing the sediment constituting the sediment pile F13 into the hole HL based on the recognized position and shape of the sediment pile F13. At this time, the controller 30 may calculate the volume or weight of the sediment constituting the sediment pile F13. There is a limit on the volume or weight of the sediment that can be pushed off by a single push-off operation, so that the target trajectory TL can be generated so as not to exceed this limit.

FIG. 11 illustrates a target trajectory TL3, which is a part of the target trajectory TL for the first push-off operation, as a dashed one-dotted line. FIG. 11 illustrates a state of the bucket 6 when the first push-off operation is completed as a solid line, and the position of the bucket 6 when the first push-off operation is started as a bucket FIG. 6B plotted as a broken line. Further, FIG. 11 illustrates a sediment F13T which has been pushed into the hole HL by the first push-off operation among the sediment constituting the sediment pile F13, and a sediment F13B which remains after the first push-off operation among the sediment constituting the sediment pile F10 with solid lines.

The sediment F13T is pushed into the hole HL by the first push-off operation, that is, by moving the claw end of the bucket 6 from right to left along the target trajectory TL3.

The sediment F13B is pushed into the hole HL by the second push-off operation, that is, by moving the claw end of the bucket 6 from right to left along a target trajectory (not illustrated) for the second push-off operation.

By performing the push-off operation including the turning operation described above, the controller 30 can push the sediment relatively close to the hole HL into the hole HL. In the example described above, the controller 30 is configured to perform the push-off operation for dropping the sediment into the hole HL using the left-side face LSF of the bucket 6, but the controller 30 may be configured to perform the push-off operation for dropping the sediment into the hole HL using a right-side face of the bucket 6. For example, the controller 30 may be configured to perform the push-off operation for dropping the sediment into the hole HL using the right-side face of the bucket 6 when the sediment constituting the sediment pile on the +Y side of the hole HL in the range Z1 is dropped into the hole HL.

Next, referring to FIGS. 12A to 12C, yet another example of autonomous control for the backfilling operation will be described. FIGS. 12A to 12C are cross-sectional views illustrating the hole HL, which correspond to FIGS. 9A and 9B. Specifically, FIGS. 12A to 12C illustrate states of a sediment GR backfilled in the hole HL by a plurality of backfilling operations. More specifically, FIG. 12A illustrates a state of the sediment GR in the hole HL before a second-to-last backfilling operation (push-off operation) is performed, FIG. 12B illustrates a state of the sediment in the hole HL after the second-to-last backfilling operation (push-off operation) is performed, and FIG. 12C illustrates a state of the sediment in the hole HL after the last backfilling operation (push-off operation) is performed.

In the example illustrated in FIGS. 12A to 12C, the controller 30 is configured to set the height of the target surface TS before the backfilling operation is performed. The target surface TS is a virtual surface, typically a virtual horizontal plane, which corresponds to the ground formed when the hole HL to be backfilled is backfilled with sediment. The controller 30 detects, for example, the hole HL and the surrounding surface CS, which is the ground around the hole HL, based on the output of the object detection device 70. The controller 30 sets the height of the target surface TS based on the height of the detected surrounding surface CS. The height of the target surface TS is typically set to be the same as the height of the surrounding surface CS. The lower dashed one-dotted line illustrated in FIG. 12A represents the target surface TS.

The controller 30 determines, for example, based on the output of the object detection device 70, whether or not a sediment pile exists within a predetermined distance range from the hole HL. When the sediment pile exists within the predetermined distance range from the hole HL, the controller 30 calculates a volume of a sediment constituting the sediment pile, for example, based on the output of the object detection device 70. The sediment pile that exists within the predetermined distance range from the hole HL is a pile of sediment to be pushed into the hole HL by a push-off operation, and is hereinafter referred to as an “adjacent sediment pile”. In the example illustrated in FIGS. 12A to 12C, the controller 30 recognizes that a sediment pile F14 exists as an adjacent sediment pile on the −X side of the hole HL (the side close to the shovel 100). Therefore, the controller 30 calculates the volume of the sediment constituting the sediment pile F14.

For example, every time the backfilling operation is completed, the controller 30 calculates a volume (required volume) of the sediment required to completely backfill the hole HL based on the output of the object detection device 70. The required volume corresponds to a volume (excluding the volume of the part already backfilled with the sediment) of the space located below the target surface TS in the hole HL. Then, the controller 30 determines whether the volume of the sediment constituting the adjacent sediment pile (sediment pile F14) is equal to or greater than the required volume. It should be noted that the controller 30 is typically configured to adjust the volume of the sediment to be backfilled into the hole HL by the preceding backfilling operation so that the required volume is approximately equal to the volume of the adjacent sediment pile.

When determining that the volume of sediment constituting the adjacent sediment pile (sediment pile F14) is equal to or greater than the required volume, the controller 30 executes an autonomous push-off operation as an autonomous backfilling operation.

Specifically, the controller 30 generates a target trajectory TL for pushing the sediment constituting the sediment pile F14 into the hole HL based on the position and shape of the sediment pile F14. In this case, the controller may set a target position with respect to the hole HL, and generate a target trajectory TL.

FIGS. 12A and 12B illustrate a target trajectory TL4, which is a part of the target trajectory TL for a second-to-final push-off operation, as a dashed one-dotted line. FIGS. 12B and 12C illustrate a target trajectory TL5, which is a part of the target trajectory TL for a final push-off operation, as a dashed two-dotted line.

FIG. 12A illustrates a state of the bucket 6 as a solid line when the second-to-final push-off operation is started. FIG. 12B illustrates a state of the bucket 6 as a solid line when the final push-off operation is started, and illustrates the sediment F14T pushed into the hole HL by the second-to-final push-off operation from among the sediments constituting the sediment pile F14 as a coarse dot pattern. FIG. 12C illustrates a state of the bucket 6 as a solid line when the final push-off operation is completed. In FIGS. 12A to 12C, for clarity, a fine dot pattern is attached to the sediment GR and the sediment pile F14 (excluding sediment F14T), and a shaded pattern is attached to the ground around the hole HL.

As illustrated in FIG. 12B, a sediment F14B, which has remained after the second-to-final push-off operation of the sediment pile F14, is pushed into the hole HL by the final push-off operation, that is, by moving the claw end of the bucket 6 along the target trajectory TL5 from the side close to the shovel 100 to the side away from the shovel, as illustrated in FIG. 12C.

By executing the push-off operation as described above, the controller 30 is able to push the sediment relatively close to the hole HL into the hole HL at the same time as leveling the surface of the sediment backfilled into the hole HL, so that the surface of the sediment backfilled into the hole HL has no irregularities. In addition, the controller 30 can make the height of the surface of the sediment backfilled into the hole HL and the height of the surrounding surface CS substantially the same. Note that, in the example illustrated in FIGS. 12A to 12C, the controller is configured to perform the push-off operation for dropping the sediment into the hole HL and the leveling operation simultaneously by using the back face BF of the bucket 6, but may be configured to perform the push-off operation for dropping the sediment into the hole HL and the leveling operation simultaneously by using the front face or the side face of the bucket 6.

Thus, the controller 30 autonomously and simultaneously performs the backfilling operation and the leveling operation, thereby reducing the operator's burden on the backfilling operation and the leveling operation by manual operation. In addition, the controller 30 can enhance the efficiency of the backfilling operation compared with the case where the backfilling operation and the leveling operation are performed separately.

As described above, the shovel 100 according to the embodiment of the present disclosure includes a lower traveling body 1, an upper turning body 3 turnably mounted on the lower traveling body 1, and the controller 30 as a control device disposed in the upper turning body 3. The controller 30 is configured to start an autonomous backfilling operation by the shovel 100 when a predetermined condition is met.

The predetermined condition is, for example, a condition in which a predetermined switch has been operated, or a condition in which the operation lever has been operated in a predetermined direction in a predetermined operation mode.

The predetermined switch is, for example, a switch NS disposed on the operation lever. The predetermined operation mode is, for example, a backfilling mode. The operator of the shovel 100 can switch an operation mode of the shovel 100 between a normal mode and the backfilling mode by, for example, operating the switch NS. When the operation mode of the shovel 100 is the backfilling mode, the operator can perform an autonomous backfilling operation as illustrated in FIGS. 7A to 7C by, for example, operating the left operation lever 26L in the left turning direction, or can perform an autonomous backfilling operation (push-off operation) as illustrated in FIGS. 10A and 10B by operating the left operation lever 26L in the arm opening direction.

This configuration can enhance the efficiency of the backfilling operation compared with the backfilling operation performed in response to the manual operation of the operation lever. In addition, this configuration can reduce the burden on the operator of the shovel 100 for the backfilling operation.

The backfilling operation may include at least one of an operation of the excavation attachment AT attached to the upper turning body 3 and a turning operation of the upper turning body 3. Specifically, the backfilling operation may include at least one of the boom raising operation, the boom lowering operation, the arm opening operation, the arm closing operation, the bucket opening operation, the bucket closing operation, the left turning operation, and the right turning operation, as illustrated in FIGS. 7A to 7C. Alternatively, the backfilling operation may not include the turning operation, as illustrated in FIGS. 10A and 10B. Alternatively, the backfilling operation may not include the operation of the excavation attachment AT. In addition, the backfilling operation may include at least one of an operation of pushing a sediment with the front face of the bucket 6, an operation of pushing a sediment with the side face SF of the bucket 6, and an operation of pushing a sediment with the back face BF of the bucket 6.

This configuration can further enhance the efficiency of the backfilling operation, for example, by enabling the autonomous execution of an appropriate backfilling operation according to a positional relationship between a hole subject to a backfilling work and a sediment pile subject to the backfilling work.

The controller 30 may be configured to specify a position of a landscape feature subject to backfilling based on an output of the object detection device 70. The landscape feature subject to backfilling may be, for example, a hole subject to backfilling and a sediment pile subject to backfilling. For example, the controller 30 may be configured to specify a position of a landscape feature subject to backfilling based on an image captured by the imaging device 80. Alternatively, the controller 30 may be configured to specify a position of a landscape feature subject to backfilling based on distance information measured by LIDAR. In this case, the controller 30 may be configured to recognize at least one of a shape, a depth, and a volume of the hole subject to backfilling; a shape, a height, and a volume of the sediment pile subject to backfilling; and a progress of the backfilling work based on an output of the object detection device 70.

The preferred embodiment of the present disclosure has been described in detail. However, the present invention is not limited to the embodiment described above, nor is it limited to what is exemplified below. The embodiment described above may be subject to various modifications, substitutions, and the like without departing from the scope of the present invention In addition, the features described separately may be combined, provided that no technical inconsistencies arise.

For example, according to the embodiment described above, the controller 30 is configured to perform the backfilling operation or the like autonomously or semi-autonomously, thereby reducing the burden on the operator sitting on a driver's seat inside the cabin 10. However, the autonomous or semi-autonomous operation by the controller 30 may be applied to a remotely operated shovel. In this case, the controller 30 can perform the backfilling operation or the like autonomously or semi-autonomously, thereby reducing the burden on a remote operator sitting on a driver's seat inside a remotely controlled room connected to the shovel 100 via wireless communication.

The controller 30 may also be configured to recognize a positional relationship between the shovel 100 and the hole HL based on the output of the object detection device 70. In this case, the controller 30 may specify the position of the hole HL based on the output of a positioning device (such as GNSS) mounted on the shovel 100. The controller 30 may be configured to recognize the positional relationship between the shovel 100 and a sediment pile based on the output of the object detection device 70. In this case, the controller 30 may specify the position of the sediment pile based on the output of the positioning device mounted on the shovel 100.

In addition, the controller 30 may be configured to recognize the position of the hole HL based on the construction plan inputted by communication, etc., when the position or shape of the hole subject to the backfilling operation is set in advance in the construction plan (design data). Similarly, the controller 30 may be configured to recognize the position of the sediment pile based on the construction plan inputted by communication, etc., when the position or the like of the sediment pile subject to the backfilling operation is set in advance in the construction plan (design data). Thus, the controller 30 can control the position of the bucket 6 by comparing the control reference point calculated based on the output of the positioning device (GNSS, etc.) or the attitude sensor, etc. mounted on the shovel 100 with the position (target position) of the sediment pile, the hole HL, or the like on the construction plan.

It should be understood that the invention is not limited to the above-described embodiment, but may be modified into various forms on the basis of the spirit of the invention. Additionally, the modifications are included in the scope of the invention.

Claims

1. A shovel comprising: a lower traveling body;an upper turning body turnably mounted on the lower traveling body; anda control device disposed in the upper turning body, wherein the control device includes a processor, and a memory storing a computer-readable program, which when executed, causes the processor to execute a process includingrecognizing a position subject to a backfilling operation, andgenerating a target position relating to the backfilling operation.

2. The shovel according to claim 1, wherein the process includes changing the target position according to a shape of a sediment at the position subject to the backfilling operation.

3. The shovel according to claim 1, wherein the process includes changing an operation content according to a height of a sediment at the position subject to the backfilling operation.

4. The shovel according to claim 1, wherein the process includes starting an autonomous backfilling operation by the shovel when a predetermined condition is met, andwherein the predetermined condition is a condition in which a predetermined switch has been operated, or a condition in which an operation lever has been operated in a predetermined direction in a predetermined operation mode.

5. The shovel according to claim 1, wherein the backfilling operation includes a push-off operation of pushing off a sediment with a bucket without lifting the sediment with the bucket, andwherein the push-off operation includes at least one of a push-off operation of pushing off the sediment with a front face of the bucket, a push-off operation of pushing off the sediment with a side face of the bucket, and a push-off operation of pushing off the sediment with a back face of the bucket.

6. The shovel according to claim 1, further comprising: an object detection device attached to the upper turning body, whereinthe process includes specifying a position of a landscape feature subject to the backfilling operation based on an output of the object detection device.

7. The shovel according to claim 1, wherein the process includes performing a leveling operation to level a surface of a sediment when a hole has been backfilled.

8. The shovel according to claim 5, wherein the process includes performing a leveling operation at a same time as performing the push-off operation.

9. The shovel according to claim 1, wherein the process includes setting, as a target surface, a virtual surface corresponding to a ground formed when a hole is backfilled,generating a target trajectory along the target surface, andperforming a leveling operation by moving a bucket along the target trajectory.

10. The shovel according to claim 9, wherein a height of the target surface is set based on a height of the ground around the hole.

11. The shovel according to claim 5, wherein the process includes performing the push-off operation when an object subject to the backfilling operation is within a predetermined distance range from a hole to be backfilled, andperforming the backfilling operation including an excavation operation when the object subject to the backfilling operation is outside the predetermined distance range from the hole to be backfilled.

12. The shovel according to claim 5, wherein when an object subject to the backfilling operation is within a predetermined distance range from a hole to be backfilled, the process includes backfilling the object subject to the backfilling operation into the hole by a plurality of the push-off operations s, the plurality of push-off operations being the push-off operation of pushing off the sediment with the bucket.

13. The shovel according to claim 5, wherein the process includes generating a target trajectory for the push-off operation based on a limit on a volume or a weight of the sediment that can be pushed off by a single push-off operation.

14. The shovel according to claim 5, further comprising: an object detection device attached to the upper turning body, wherein the process includescalculating, based on an output of the object detection device, a volume of an object subject to the backfilling operation within a predetermined distance range from a hole, and a volume of a sediment required to backfill the hole as a required volume,performing the backfilling operation including an excavation operation when the volume of the object subject to the backfilling operation is less than the required volume, andperforming the push-off operation when the volume of the object subject to the backfilling operation is equal to or greater than the required volume.

15. The shovel according to claim 1, further comprising: an object detection device attached to the upper turning body, wherein the process includesrecognizing an opening area or a depth of a hole to be backfilled based on an output of the object detection device, andsetting the target position based on the opening area or the depth.