WO2025164160A1 - Work machine control device, work machine, external device for work machine, work machine system, and position correction method - Google Patents

Abstract

A work machine (100) comprises: a machine body; a mobile unit (14) the relative position of which with respect to the machine body can be changed; and a site information acquisition unit (20) that is attached to the mobile unit (14) and that acquires information on a work site. A work machine control device (40) comprises a controller (50) that corrects the position of the site information acquisition unit (20) using: first position information correlated with the position of the site information acquisition unit (20) when the mobile unit (14) is disposed at a first position (Pa); and second position information correlated with the position of the site information acquisition unit (20) when the mobile unit (14) is disposed at a second position (Px) different from the first position (Pa).

Description

Work machine control device, work machine, external device for work machine, work machine system, and position correction method

This disclosure relates to technology for work machines such as hydraulic excavators.

Generally, work machines such as hydraulic excavators are equipped with a lower traveling body, an upper rotating body that is rotatably supported on the lower traveling body, and a work implement that is rotatably supported on the upper rotating body. The work implement includes, for example, a boom, an arm, and an end attachment such as a bucket. The upper rotating body includes a rotating frame and a cab that is supported on the rotating frame. Operating devices such as control levers are located in the cab, and the work machine performs operations in response to operations applied to the operating devices by the operator.

Incidentally, when assist control is performed to assist operators and other workers involved in the work, such as in the case of automatic driving control that automates the operation of a work machine, a site information acquirer such as LiDAR may be attached to the work machine to acquire information about the work target at the work site. However, when the site information acquirer is attached to a movable part whose relative position to the machine body can be changed, such as a cab that can be raised and lowered relative to the machine body (see, for example, Patent Documents 1 and 2), the controller may not be able to appropriately control the work machine using the work site information acquired by the site information acquirer.

JP 2014-141837 A JP 2016-176288 A

The purpose of this disclosure is to provide a work machine control device, work machine, external device for a work machine, work machine system, and position correction method that can appropriately control a work machine using work site information acquired by a site information acquirer, even when the site information acquirer is attached to a movable part whose relative position to the machine body can be changed.

The work machine control device according to the first aspect is a work machine control device for controlling a work machine that includes a machine main body, a movable part whose position relative to the machine main body can be changed, and a site information acquirer attached to the movable part and that acquires work site information, which is information about the work site. The work machine control device includes a controller that corrects the position of the site information acquirer using first position information that correlates with the position of the site information acquirer when the movable part is located at a first position, and second position information that correlates with the position of the site information acquirer when the movable part is located at a second position different from the first position.

1 is a side view showing a work machine according to a first embodiment. FIG. 1 is a block diagram showing components of a work machine according to a first embodiment. FIG. 5A to 5C are diagrams for explaining an example of a position correction method according to the first embodiment. FIG. 2 is a diagram for explaining a work target and a reference position at a work site. 3 is a flowchart showing a calculation process performed by a controller of the work machine control device according to the first embodiment. FIG. 2 is a diagram showing a work machine system including a work machine control device according to a modified example of the first embodiment. FIG. 10 is a diagram showing a work machine equipped with a work machine control device according to a second embodiment. 10 is a flowchart showing a calculation process performed by a controller of a work machine control device according to a second embodiment. FIG. 10 is a diagram showing a work machine according to a modified example. 1 is a diagram showing a work machine system equipped with a work machine control device according to a reference example.

Embodiments of the present disclosure will be described with reference to the drawings.

[First embodiment]
Figure 1 is a side view showing a work machine 100 according to the first embodiment. As shown in Figure 1, the work machine 100 comprises a lower running body 1 including a traveling device, an upper rotating body 2 supported on the lower running body 1 so as to be rotatable relative to the lower running body 1 about a rotation axis A extending vertically, a work device 3 supported on the upper rotating body 2, a plurality of actuators, and an attitude information acquirer 80 (see Figure 2).

The work machine 100 in this embodiment is a hydraulic excavator, but the work machine in this disclosure is not limited to hydraulic excavators and may be other work machines such as cranes or bulldozers. The travel device may be a crawler travel device as shown in FIG. 1, or a travel device with tires (not shown).

Note that the front-to-rear and left-to-right directions shown in the figures are directions based on the orientation of the upper rotating body 2. Specifically, the front-to-rear direction is a horizontal direction parallel to the longitudinal direction of the work device 3 in a plan view, and the left-to-right direction is a horizontal direction perpendicular to the front-to-rear direction.

The work device 3 includes a boom 4 that is attached to the upper rotating body 2 so that it can be raised and lowered, an arm 5 that is attached to the boom 4 so that it can rotate, and a tip attachment 6 that is attached to the arm 5 so that it can rotate. In this embodiment, the tip attachment 6 is a bucket, but the tip attachment may also be other tip attachments such as a grapple, fork, crusher, or lifting magnet.

Each of the multiple actuators operates by receiving a supply of hydraulic oil discharged from a hydraulic pump (not shown). The multiple actuators include a boom cylinder 7 for raising and lowering the boom 4, an arm cylinder 8 for rotating the arm 5, a tip attachment cylinder 9 for rotating the tip attachment 6, a swing motor (not shown) for rotating the upper swing body 2 relative to the lower running body 1, and a travel motor (not shown) for traveling the lower running body 1. The multiple actuators may also include a lifting actuator 10 for raising and lowering the cab 14.

The upper rotating body 2 comprises a rotating frame 11, a counterweight 12, a cab support 13, a cab 14, and a center section 15 (see Figure 3). In this embodiment, the rotating frame 11 and the cab support 13 are an example of the machine body. That is, in this embodiment, the machine body includes the rotating frame 11 and the cab support 13.

The swivel frame 11 is a frame that is rotatably supported on the lower running body 1 and forms the base portion of the upper swivel body 2. The counterweight 12 is located at the rear of the upper swivel body 2.

The counterweight 12 is a weight used to balance the work machine 100. The cab support 13 is supported on the swivel frame 11 forward of the counterweight 12.

The cab support portion 13 supports the cab 14. The cab 14 may be supported by the cab support portion 13 via a lifting actuator 10. The lifting actuator 10 may be, for example, a cylinder such as a hydraulic cylinder or an electric cylinder, or a motor such as a hydraulic motor or an electric motor.

The cab 14 is a so-called elevator cab. In response to the operation of the lifting actuator 10, the cab 14 rises and falls relative to the cab support 13 within a range between the lowest position Pa and the highest position Pb shown in FIG. 1. The cab 14 is an example of a movable part that can change its position relative to the machine body. The cab 14 is located in front of the cab support 13 and is supported by the revolving frame 11 via the lifting actuator 10 and the cab support 13. The cab 14 is located, for example, at the left front of the revolving frame 11.

The cab 14 may be configured to rise and fall along the vertical direction, or along a direction inclined at a predetermined angle relative to the vertical direction. The cab 14 may be configured to rise and fall along a linear track, a curved track, or a track that includes a linear track and a curved track.

The cab 14 is equipped with a driver's seat, an operating device 16, and other components. The operating device 16 includes controls that receive various operations from the operator, such as boom operation for raising and lowering the boom 4, arm operation for rotating the arm 5, tip attachment operation for rotating the tip attachment 6, rotation operation for rotating the upper rotating body 2 relative to the undercarriage 1, and travel operation for traveling the undercarriage 1. The operating device 16 may also include a control that receives a lifting operation for raising and lowering the cab 14. The control may be composed of at least one of an operating lever, an operating pedal, and an operating button.

The center section 15 has a portion that rises upward from the revolving frame 11, and this portion rotatably supports the boom 4. The center section 15 also rotatably supports the base end of the boom cylinder 7. Specifically, the base end of the boom cylinder 7 is rotatably attached to the center section 15, and the tip end of the boom cylinder 7 is rotatably attached to the boom 4.

The attitude information acquirer 80 (see Figure 2) acquires attitude information, which is information relating to the attitude of the work machine 100. As shown in Figure 1, the attitude information acquirer 80 may include multiple attitude detectors. The multiple attitude detectors may include a boom attitude detector 81, an arm attitude detector 82, and a tip attachment attitude detector 83. The multiple attitude detectors may further include a rotating body attitude detector 84.

The boom position detector 81 may be a sensor that detects the position of the boom 4, or may be a sensor that detects the state of the boom cylinder 7 that correlates with the position of the boom 4. The arm position detector 82 may be a sensor that detects the position of the arm 5, or may be a sensor that detects the state of the arm cylinder 8 that correlates with the position of the arm 5. The tip attachment position detector 83 may be a sensor that detects the position of the tip attachment 6, or may be a sensor that detects the state of the tip attachment cylinder 9 that correlates with the position of the tip attachment 6. The rotating body position detector 84 may be a sensor that detects the position of the upper rotating body 2, or may be a sensor that detects the state of the rotating motor that correlates with the position of the upper rotating body 2.

Each of the multiple attitude detectors may include, for example, an inertial measurement unit (IMU), a sensor that detects the degree of extension and contraction of the cylinder (e.g., a stroke sensor), or other sensors. The rotating body attitude detector 84 may include a sensor that detects the rotation angle of the upper rotating body 2 relative to the lower running body 1, or a sensor that detects the inclination angle of the upper rotating body 2 relative to the horizontal plane.

The attitude information acquirer 80 inputs the acquired attitude information to the controller 50, which will be described later. The controller 50 can calculate the attitude of the work machine 100 using the attitude information input from the attitude information acquirer 80.

As shown in FIG. 2, the work machine 100 includes a site information acquirer 20 and a work machine control device 40. The work machine control device 40 includes a controller 50.

The site information acquirer 20 is a device for acquiring work site information, which is information about the work site. As shown in FIG. 2, the site information acquirer 20 inputs the acquired work site information (e.g., point cloud data) into the controller 50. In this embodiment, the site information acquirer 20 is attached to the cab 14 (an example of a movable part). Specifically, the site information acquirer 20 may be attached to the front part of the top surface of the cab 14.

The site information acquirer 20 may be a three-dimensional position information acquirer configured to acquire three-dimensional position information (e.g., point cloud data) of objects present at the work site, such as the ground, obstacles, and other work machines. Specific examples are as follows:

The site information acquirer 20 may be a distance measuring sensor that acquires distance information regarding the distance to an object by irradiating light such as laser light. The distance measuring sensor may be, for example, a LiDAR (Light Detection and Ranging). The site information acquirer 20 may also be a stereo camera, an ultrasonic sensor, a total station, or other sensor capable of acquiring three-dimensional position information. The site information acquirer 20 may also be a height detection device that can detect the height of the site information acquirer 20. The site information acquirer 20 may also be a combination of two or more of these devices.

The controller 50 is equipped with a computer including an arithmetic processing unit and memory. The controller 50 realizes the functions of the work machine control device 40, such as the assist control, by having the arithmetic processing unit execute programs stored in the memory.

The controller 50 controls the operation of the work machine 100. In this embodiment, the controller 50 performs assist control to assist those involved in the work, such as the operator, work manager, and assistant. The assist control may be, for example, control for automatic operation (automatic operation control) that automates the operation of the work machine 100, control for semi-automatic operation (semi-automatic operation control) that automates part of the operation of the work machine 100, control for the operator to remotely operate the work machine 100 using a remote operation device (not shown) located in a remote location away from the work machine 100 (remote operation control), or other control to assist the those involved in the work.

In the specific example shown in Figure 2, the controller 50 includes a correction controller 51 (periphery recognition controller), a driving control controller 52, and an assist data memory 53.

The correction controller 51 performs position correction control to correct the position of the site information acquirer 20. The position correction control may include not only correction of the position of the site information acquirer 20, but also correction of the orientation of the site information acquirer 20, as in the second embodiment described below.

The operation controller 52 controls the work machine 100, including the assist control, using the work site information input from the site information acquirer 20.

The assist data memory 53 stores assist data, which is data for the assist control. The assist data may be, for example, automatic driving data for the automatic driving or semi-automatic driving. The automatic driving data is used, for example, to calculate control commands that the controller 50 outputs to the controlled object 70 so that the work machine 100 performs a specified operation. The automatic driving data may be, for example, teaching data corresponding to operations given by the operator to the operating device in the cab 14 or the remote operating device, or may be data created using various information terminals.

The controller 50 performs the assist control using the work site information input from the site information acquirer 20 and the attitude information input from the attitude information acquirer 80. Specifically, for example, if the assist control is automatic driving control or semi-automatic driving control, the controller 50 outputs a control command to the controlled object 70 so that the work machine 100 performs an operation corresponding to the automatic driving data stored in advance in the assist data memory 53.

The controlled object 70 is an object controlled by the operation control controller 52 of the controller 50. The output of the controlled object 70 changes in accordance with a control operation amount (control input), which is an operation amount input from the controller 50. The controlled object 70 may include a flow regulator and at least one of the plurality of actuators. The flow regulator adjusts the direction and flow rate of hydraulic oil supplied to at least one of the plurality of actuators in accordance with the control operation amount input from the controller 50. In other words, when the controller 50 inputs a control operation amount to the flow regulator, the flow regulator operates in accordance with the control operation amount input from the controller 50, thereby supplying hydraulic oil from the hydraulic pump to at least one of the plurality of actuators and operating that actuator.

The flow rate regulator may include, for example, a plurality of proportional valves 71 and a control valve 72. The control valve 72 has a plurality of spools corresponding to the plurality of actuators. The control valve has a pair of pilot ports corresponding to each spool. Each of the plurality of spools is actuated by inputting pilot pressure to one of the pair of pilot ports corresponding to that spool, allowing hydraulic oil to be supplied to the actuator corresponding to that spool. Each of the plurality of proportional valves 71 is disposed in an oil passage connecting the pilot port of the spool corresponding to that proportional valve 71 to a pilot pump (not shown), and adjusts the pilot pressure input to the pilot port. In other words, each of the plurality of proportional valves 71 outputs a secondary pressure corresponding to the control operation amount (e.g., current value) input from the controller 50, and the secondary pressure is input as pilot pressure to the pilot port corresponding to that proportional valve 71. Each of the plurality of proportional valves 71 adjusts the pilot pressure input to the pilot port corresponding to that proportional valve 71 to a magnitude corresponding to the control operation amount input from the controller 50.

The multiple proportional valves 71 may include a pair of boom proportional valves 71 for controlling the operation of the boom cylinder 7, a pair of arm proportional valves 71 for controlling the operation of the arm cylinder 8, a pair of tip attachment proportional valves 71 for controlling the operation of the tip attachment cylinder 9, a pair of swing proportional valves 71 for controlling the operation of the swing motor, and a pair of travel proportional valves 71 for controlling the travel motor. Furthermore, if the lifting actuator 10 is a hydraulic actuator such as a hydraulic cylinder or hydraulic motor, the multiple proportional valves 71 may further include a pair of lifting proportional valves 71 for controlling the operation of the lifting actuator 10.

In this embodiment, the cab 14 is an elevator cab (an example of a movable part) that can be raised and lowered relative to the machine body (swivel frame 11 and cab support part 13), and since the site information acquirer 20 is attached to this cab 14, the controller 50 performs the following position correction control at least either before or during the execution of assist control.

In the position correction control, the controller 50 corrects the position of the site information acquirer 20 using first position information that correlates with the position of the site information acquirer 20 when the cab 14 is located at a first position (for example, the lowest position Pa shown in the upper diagram (A) of Figure 3), and second position information that correlates with the position of the site information acquirer 20 when the cab 14 is located at a second position different from the lowest position Pa (for example, the work position Px shown in the center diagram (B) of Figure 3).

Therefore, in this embodiment, even if the relative position between the site information acquirer 20 attached to the cab 14 and the work object at the work site changes as the cab 14 displaces relative to the machine body, the assist control of the work machine 100 is performed appropriately using the work site information acquired by the site information acquirer 20.

Each of the first position information and the second position information may be information represented by coordinates in a coordinate system based on the site information acquirer 20 (acquirer coordinate system), information represented by coordinates in a coordinate system based on the work machine 100 (machine coordinate system), information represented by coordinates in a coordinate system based on a specific position at the work site (site coordinate system), or information represented by coordinates in a global coordinate system. The controller 50 may be configured to be able to convert position information in any of these coordinate systems into position information in the other coordinate system.

In the following specific example, the controller 50 is configured to convert point cloud data in the acquirer coordinate system input from the site information acquirer 20 into point cloud data in a predefined reference coordinate system. The reference coordinate system may be the machine coordinate system, the site coordinate system, the global coordinate system, or another coordinate system.

The origin O of the reference coordinate system may be set at a specific position relative to the work machine 100, for example. Specifically, the origin O of the reference coordinate system may be, for example, any position on the rotation axis A. More specifically, the origin O of the reference coordinate system may be the intersection of the rotation axis A and the ground. Furthermore, the origin O of the reference coordinate system may be, for example, a position on the rotation axis A between the lower traveling body 1 and the upper rotating body 2 (specific position SP in Figure 1).

In this embodiment, the reference coordinate system is a three-dimensional coordinate system. In this case, the reference coordinate system may be, for example, a Cartesian coordinate system defined using an x-axis parallel to the left-right direction, a y-axis parallel to the front-back direction, and a z-axis parallel to the vertical direction. However, the reference coordinate system is not limited to the above specific example, and various other aspects can be adopted.

The controller 50 may pre-store an initial setting position for the cab 14. The initial setting position is a position of the cab 14 that is pre-set as a reference position when correcting the position of the site information acquirer 20. The initial setting position may be, for example, the lowest position Pa. The initial setting position (lowest position Pa) is an example of the first position.

The controller 50 may pre-store information (initial relative position information) regarding the relative position of the site information acquirer 20 with respect to the specific position SP when the cab 14 is positioned at the initial setting position (first position). Specifically, for example, the controller 50 may store, as the initial relative position information, acquirer initial coordinates C0, which are coordinates in the reference coordinate system with the specific position SP as the origin and are the coordinates of the site information acquirer 20 when the cab 14 is positioned at the lowest position Pa. The coordinates of the site information acquirer 20 may be, for example, the coordinates of the viewpoint of the site information acquirer 20, or the coordinates of another part of the site information acquirer 20.

If the cab 14 moves up or down from the initial setting position (first position) to the second position, changing the relative position of the site information acquirer 20 with respect to the machine body (swivel frame 11 and cab support portion 13), the controller 50 may correct the position of the site information acquirer 20 as follows:

In other words, the controller 50 may acquire, as the first position information, a first coordinate C1, which is the coordinate of a reference position RP described below when the cab 14 is positioned at the initial setting position (first position), and may acquire, as the second position information, a second coordinate C2, which is the coordinate of the reference position RP when the cab 14 is positioned at the second position (e.g., the work position Px in Figure 3).

The first coordinate C1 may be the coordinate of the reference position RP identified by the controller 50 based on point cloud data input from the site information acquirer 20 to the controller 50 when the cab 14 is placed at the first position. Similarly, the second coordinate C2 may be the coordinate of the reference position RP identified by the controller 50 based on point cloud data input from the site information acquirer 20 to the controller 50 when the cab 14 is placed at the second position.

The reference position RP does not fluctuate, at least during the time period when position correction control is performed. Meanwhile, the first coordinate C1 and second coordinate C2 are each calculated using the initial relative position information (e.g., the acquirer initial coordinate C0). Therefore, even though the reference position RP does not fluctuate, the first coordinate C1 and the second coordinate C2 have different values. The difference ΔC between the first coordinate C1 and the second coordinate C2 corresponds to the change in the coordinate of the site information acquirer 20 that occurs as the cab 14 rises and falls from the first position (the initial setting position) to the second position.

Therefore, the controller 50 may correct the position of the on-site information acquirer 20 using the difference ΔC between the first coordinate C1 and the second coordinate C2. Specifically, the controller 50 may calculate the acquirer corrected coordinate C0' by substituting the acquirer initial coordinate C0 and the difference ΔC into a predetermined relational expression set to correct the position of the on-site information acquirer 20.

The calculated corrected acquirer coordinates C0' are coordinates in the reference coordinate system with the specific position SP as the origin, and are the coordinates of the site information acquirer 20 when the cab 14 is located at a second position (e.g., work position Px). Therefore, the controller 50 can appropriately perform the assist control after the position correction control using the corrected acquirer coordinates C0' corrected in the position correction control and the point cloud data acquired by the site information acquirer 20. In other words, the assist control is appropriately performed for the specified work performed when the cab 14 is located at the second position (e.g., work position Px).

Here, an example of the reference position RP will be described. In this embodiment, as shown in Figures 3 and 4, a reference object 60 is placed at the work site WS. The reference object 60 is an object that serves as a reference for correcting the position of the site information acquirer 20 in position correction control by the controller 50. The relative position of the reference object 60 with respect to the work target WT at the work site WS does not change, at least during the time period when position correction control is performed.

It is preferable that the reference object 60 is placed at the work site WS in a manner that makes it easy to distinguish from objects surrounding the reference object 60. Specifically, for example, it is preferable that the reference object 60 is placed at a position higher than the ground around the reference object 60 at the work site WS. The reference object 60 may be placed at a position higher than the surrounding ground by being supported, for example, by a rod-shaped support member. It is preferable that the reference object 60 has a highly reflective surface so that it can be easily detected by a ranging sensor such as LiDAR. It is preferable that the reference object 60 has a color (e.g., white, yellow, etc.) that is easily detected by a ranging sensor such as LiDAR. The reference object 60 may be, for example, a sphere, or may have another shape.

The reference object 60 is placed at a position that is included in the field of view of the site information acquirer 20 when the work machine 100 is placed near the work target WT, as shown in Figures 3 and 4, for example. In the specific example shown in Figure 4, the reference object 60 is placed next to the work target WT, but the placement of the reference object 60 is not limited to the specific example shown in Figure 4.

When a reference object 60 is placed at the work site WS, the controller 50 may use point cloud data input from the site information acquirer 20 to identify a reference position RP (reference point), which is the position of the reference object 60. The controller 50 may calculate the coordinates of the reference position RP using the point cloud data input from the site information acquirer 20. The coordinates of the reference position RP may be, for example, coordinates corresponding to the center of the reference object 60, coordinates corresponding to the top end of the reference object 60, or coordinates corresponding to another part of the reference object 60.

Specifically, for example, the controller 50 may identify the coordinates of the reference position RP using point cloud data input from the site information acquirer 20 (e.g., LiDAR) and characteristic information related to the characteristics of the reference object 60. The characteristic information may include, for example, at least one of information related to the size (e.g., outer diameter) of the reference object 60, information related to the shape (e.g., spherical) of the reference object 60, information related to the installation height (height from the ground) of the reference object 60, and information related to the reflectance or color of the reference object 60. The characteristic information may be stored in advance in the controller 50 before the start of position correction control.

Next, an example of the assist control will be described. In the specific example shown in Figures 3 and 4, the work machine 100 is placed at a work site WS and performs a predetermined task on a work target WT set at the work site WS. The predetermined task may be, for example, loading work, ground leveling work, or some other task. The controller 50 performs the assist control so that the work machine 100 performs the predetermined task.

Specifically, for example, the controller 50 performs automatic driving control or semi-automatic driving control using the point cloud data input from the site information acquirer 20 and the attitude information input from the attitude information acquirer 80. The controller 50 outputs a control command to the control target 70 so that the work machine 100 performs an operation corresponding to the automatic driving data stored in advance in the assist data memory 53.

Loading operations include an excavation step, a lifting and swinging step, a soil discharge step, and a return swinging step. The excavation step, lifting and swinging step, soil discharge step, and return swinging step are performed in this order. The excavation step is an operational step for excavating the work object WT, such as the ground. The work object WT may be, for example, the target excavation area indicated by the dashed-dotted line frame in Figure 4. The lifting and swinging step is an operational step for moving the bucket 6 holding the excavated soil from the work object WT to directly above the soil discharge area. The soil discharge area may be, for example, the bed of a dump truck (not shown), or an area for soil discharge formed at the work site WS. The soil discharge step is an operational step for discharging soil from the bucket 6 to the soil discharge area. The return swinging step is an operational step for returning the bucket 6 from directly above the soil discharge area to the work object WT.

Teaching data corresponding to loading operations that include multiple operational steps may be stored in the assist data storage device 53, or may be stored in an external device that is separate from the work machine 100.

Figure 5 is a flowchart showing the calculation process for position correction control performed by the controller 50 of the work machine control device 40.

As shown in the upper diagram (A) of Figure 3, when the work machine 100 is positioned near the work object WT and the cab 14 is positioned in the initial setting position, the controller 50 acquires the coordinates of the reference position RP (first coordinates C1) (step S11 of Figure 5).

Specifically, in step S11, with the cab 14 positioned at the lowest position Pa as the initial setting position, the controller 50 calculates the first coordinate C1 of the reference position RP using point cloud data input from the site information acquirer 20 (e.g., LiDAR). The controller 50 then stores the calculated first coordinate C1 (step S12).

Next, the controller 50 controls the operation of the lifting actuator 10 so that the cab 14 is raised or lowered (step S13). Specifically, if the initial setting position is the lowest position Pa, the controller 50 controls the operation of the lifting actuator 10 so that the cab 14 is raised from the lowest position Pa to the target height position.

The target height position may be, for example, a working position Px as shown in the center diagram (B) of Figure 3. The working position Px is the position of the cab 14 when the work machine 100 is performing work at the work site. The working position Px is determined appropriately depending on various conditions, such as the type of work to be performed at the work site and the specifications of the work machine 100. In the specific example shown in the center diagram (B) of Figure 3, the working position Px is above the lowest position Pa and below the highest position Pb. However, the working position Px may be either the highest position Pb or the lowest position Pa.

The target height position (e.g., work position Px) may be set based on an input operation by a person involved in the work. The input operation may be, for example, an operation on an input device inside the cab 14, or an operation on an external device that is separate from the work machine 100. The input operation may include, for example, an input to specify the target height position, which is any height position between the lowest position Pa and the highest position Pb. In this case, the cab 14 continues to rise and fall from the lowest position Pa, which is the initial setting position, to the work position Px, which is the target height position.

Furthermore, the target height position (e.g., working position Px) may be a position determined in response to a lifting/lowering operation given by a worker to the operating device 16 inside the cab 14, or a position determined in response to a lifting/lowering operation given by a worker to the remote operating device. In this case, the cab 14 continues to lift/lower while a lifting/lowering operation is given to the operating device 16 or the remote operating device.

Once the cab 14 has been raised or lowered and is positioned at the target height (e.g., work position Px), the controller 50 acquires the coordinates of the reference position RP (second coordinates C2) (step S14). Specifically, in step S14, with the cab 14 positioned at the work position Px, the controller 50 calculates the second coordinates C2 of the reference position RP using the point cloud data input from the site information acquirer 20.

Next, the controller 50 compares the first coordinate C1 and the second coordinate C2 to determine whether a predetermined condition for determining whether position correction is necessary is met (step S15). The condition for determining whether position correction is necessary may be, for example, the condition that the first coordinate C1 and the second coordinate C2 do not match (ΔC = C1 - C2 ≠ 0), as described in step S15 of FIG. 5, or the condition that the difference ΔC between the first coordinate C1 and the second coordinate C2 is not included in a predetermined tolerance range Th (|C1 - C2| > Th).

If the condition for determining whether position correction is necessary is met (YES in step S15), the controller 50 corrects the position of the on-site information acquirer 20 using the difference ΔC between the first coordinate C1 and the second coordinate C2 as a correction value (step S16). Specifically, if the first coordinate C1 is (x1, y1, z1) and the second coordinate C2 is (x2, y2, z2), the difference ΔC can be expressed, for example, by the following relational expression (1):

ΔC=(Δx, Δy, Δz) ...(1)
(Δx=x1-x2, Δy=y1-y2, Δz=z1-z2)

The controller 50 pre-stores the initial coordinates C0 (x0, y0, z0) of the site information acquirer 20 when the cab 14 is positioned at the lowest position Pa (the initial setting position).

In step S16, the controller 50 obtains the corrected coordinates C0' of the acquirer by correcting the initial coordinates C0 of the acquirer using the difference ΔC. Specifically, for example, the controller 50 may calculate the corrected coordinates C0' (x0', y0', z0') of the acquirer by substituting the initial coordinates C0 and the difference ΔC into the following relational expression (2):

C0'=C0+ΔC...(2)
(x0'=x0+Δx, y0'=y0+Δy, z0'=z0+Δz)

Next, the controller 50 performs the process of step S14 again. That is, the controller 50 acquires the coordinates of the reference position RP (second coordinates C2) again (step S14). Specifically, in the second execution of step S14, the controller 50 calculates the second coordinates C2 of the reference position RP using the point cloud data input from the site information acquirer 20, with the cab 14 positioned at the work position Px.

Next, the controller 50 compares the first coordinate C1 with the second coordinate C2 to determine whether the position correction necessity determination condition is met (step S15). The first coordinate C1 is calculated using the coordinates stored in step S12, i.e., the acquirer initial coordinate C0 (the initial relative position information), and the second coordinate C2 is calculated using the coordinates calculated in the second step S14, i.e., the acquirer corrected coordinate C0'. Therefore, in the comparison between the first coordinate C1 and the second coordinate C2 in the second step S15, the difference ΔC between the first coordinate C1 and the second coordinate C2 is smaller than in the first step S15.

Next, if the condition for determining whether position correction is necessary is not met (NO in step S15), the controller 50 terminates the position correction control. Specifically, for example, the controller 50 may terminate the position correction control if the first coordinate C1 and the second coordinate C2 match (ΔC = 0), or if the difference ΔC is within the allowable range Th (|C1 - C2| ≦ Th).

On the other hand, if the position correction necessity determination condition is also satisfied in the second iteration of step S15 (YES in step S15), the controller 50 again corrects the position of the on-site information acquirer 20 using the difference ΔC between the first coordinate C1 and the second coordinate C2 (step S16). That is, specifically, in the second iteration of step S16, for example, the controller 50 may again calculate the acquirer corrected coordinates C0' (x0', y0', z0') by substituting the acquirer initial coordinates C0 and the difference ΔC into the above relational expression (2). This further improves the accuracy of the position correction of the on-site information acquirer 20.

The controller 50 repeats the processing from step S14 onwards until the condition for determining whether position correction is necessary is no longer met in step S15.

[Modification of the first embodiment]
FIG. 6 is a diagram showing a work machine system 300 including a work machine control device 40 according to a modification of the first embodiment.

The work machine system 300 according to the modified example shown in Figure 6 includes a work machine 100 and an external device 200 (external device for a work machine). In this modified example, the work machine 100 includes a communication device 91, and the external device 200 includes a communication device 92, so that the work machine 100 and the external device 200 can send and receive data to and from each other via wireless or wired communication.

The work machine control device 40 in this modified example has the same configuration and functions as the work machine control device 40 according to the embodiment described with reference to Figures 1 to 5. In this modified example, the work machine control device 40 may be included in the work machine 100 or the external device 200.

Furthermore, in this modified example, the work machine 100 may include part of the configuration of the work machine control device 40, and the external device 200 may include the remaining configuration of the work machine control device 40. In this case, one of the correction controller 51 and the operation control controller 52 of the controller 50 shown in FIG. 3 may be mounted on the work machine 100, and the other on the external device 200. Furthermore, the assist data memory 53 of the controller 50 shown in FIG. 3 may be mounted on either the work machine 100 or the external device 200.

The external device 200 may be, for example, a remote control device for remotely controlling the work machine 100 at a remote location away from the work machine 100. The external device 200 may also be a management device such as a server for managing work performed by the work machine 100. The external device 200 may also be an external storage device that stores data such as the teaching data. The external device 200 may also be a computer in a cloud service provided as a service over a network such as the Internet.

In the work machine system 300 according to this modified example, the controller 50 of the work machine control device 40 may perform position correction control, for example, as shown in the flowchart of Figure 5.

Note that the cab 14 of the work machine 100 in the work machine system 300 according to the modified example shown in Figure 6 does not have to be an elevator cab that can be raised and lowered relative to the machine body, but may be a cab that can rotate relative to the machine body as in the second embodiment described below. In this case, the controller 50 in the work machine system 300 may perform position correction control, for example, as shown in the flowchart of Figure 8, as in the second embodiment described below.

Second Embodiment
FIG. 7 is a diagram showing a work machine 100 equipped with a work machine control device 40 according to the second embodiment.

The work machine 100 according to the second embodiment differs from the work machine 100 according to the first embodiment in that a movable part (e.g., the cab 14) rotates relative to the machine body rather than moving up and down relative to the machine body. The basic configuration of the work machine 100 according to the second embodiment is similar to the basic configuration of the work machine 100 according to the first embodiment. Therefore, the main features of the second embodiment that differ from the first embodiment will be described below, and a detailed description of the configuration of the second embodiment that is similar to the first embodiment will be omitted.

The work machine 100 according to the second embodiment shown in Figure 7 comprises a lower traveling body 1, an upper rotating body 2, a work implement 3, multiple actuators, an attitude information acquirer 80, a site information acquirer 20, and a work machine control device 40.

The upper rotating body 2 includes a rotating frame 11 and a cab 14. The cab 14 is rotatably supported on the rotating frame 11. The rotating frame 11 in the second embodiment is an example of the machine body. That is, in this second embodiment, the machine body includes the rotating frame 11.

In the second embodiment, the multiple actuators include a rotation actuator 17 instead of the lifting actuator 10 in the first embodiment. The rotation actuator 17 operates to rotate the cab 14 around the rotation axis A1 shown in FIG. 7. The rotation axis A1 may be located, for example, at the rear of the cab 14. Specifically, the rotation axis A1 may be located at the rear and lower part of the cab 14, as shown in FIG. 7. In this case, when the cab 14, which is in the first position indicated by the solid line in FIG. 7, rotates around the rotation axis A1, the height of the front of the cab 14 gradually increases, reaching, for example, a second position indicated by the two-dot chain line in FIG. 7. The first position may be, for example, a position when the rotation angle of the cab 14 relative to the machine body (swivel frame 11) is zero degrees; specifically, a position where the floor of the cab 14 is approximately horizontal. The second position may be, for example, a position where the rotation angle of the cab 14 relative to the machine body (swivel frame 11) is greater than zero (e.g., an acute angle).

The rotary actuator 17 may be, for example, a cylinder such as a hydraulic cylinder or an electric cylinder, or a motor such as a hydraulic motor or an electric motor. If the rotary actuator 17 is, for example, a hydraulic actuator such as a hydraulic cylinder or a hydraulic motor, the plurality of proportional valves 71 of the flow regulator may further include a pair of rotary proportional valves 71 for controlling the operation of the rotary actuator 17.

The attitude information acquirer 80, site information acquirer 20, and work machine control device 40 in the second embodiment are similar to the attitude information acquirer 80, site information acquirer 20, and work machine control device 40 in the first embodiment described with reference to Figures 1 to 5. In the second embodiment, the attitude information acquirer 80 also includes multiple attitude detectors 81 to 84, similar to the attitude information acquirer 80 in the first embodiment, the site information acquirer 20 is attached to the cab 14 (an example of a movable part), and the work machine control device 40 includes a controller 50 similar to the controller 50 shown in Figure 2.

In the second embodiment, the controller 50 may also store in advance an initial setting position for the cab 14. This initial setting position is a position of the cab 14 that is set in advance as a reference position when correcting the position of the site information acquirer 20. The initial setting position may be, for example, the first position shown in FIG. 7.

The controller 50 may pre-store information (initial relative position information) regarding the relative position of the site information acquirer 20 with respect to the specific position SP when the cab 14 is located at the initial setting position (first position). Specifically, for example, the controller 50 may store, as the initial relative position information, the acquirer initial coordinates C0, which are coordinates in the reference coordinate system with the specific position SP as the origin and are the coordinates of the site information acquirer 20 when the cab 14 is located at the first position.

If the cab 14 rotates from the first position (the initial setting position) shown by the solid line in Figure 7 to the second position shown by the two-dot chain line in Figure 7, changing the relative position of the site information acquirer 20 with respect to the machine body (swivel frame 11), the controller 50 may correct the position of the site information acquirer 20 as follows.

In other words, the controller 50 may identify a first coordinate C1, which is the coordinate of the reference position RP, as the first position information using work site information acquired by the work site information acquirer 20 when the cab 14 is located at the first position, and may identify a second coordinate C2, which is the coordinate of the reference position RP, as the second position information using work site information acquired by the work site information acquirer 20 when the cab 14 is located at the second position. The controller 50 may also acquire first reference plane information, which is information about the ground surface of the work site WS when the cab 14 is located at the first position, and acquire second reference plane information, which is information about the ground surface of the work site WS when the cab 14 is located at the second position.

The first coordinate C1 may be the coordinate of the reference position RP identified by the controller 50 based on point cloud data input from the site information acquirer 20 to the controller 50 when the cab 14 is placed at the first position. Similarly, the second coordinate C2 may be the coordinate of the reference position RP identified by the controller 50 based on point cloud data input from the site information acquirer 20 to the controller 50 when the cab 14 is placed at the second position.

The first reference plane information may be information about the ground of the work site WS (e.g., information about the ground of the work target WT) identified by the controller 50 based on point cloud data input from the site information acquirer 20 to the controller 50 when the cab 14 is placed at the first position. Specifically, for example, the first reference plane information may include information about the first reference plane S1 as follows: The controller 50 may identify a plane corresponding to the ground as the first reference plane S1 based on the point cloud data input from the site information acquirer 20 when the cab 14 is placed at the first position. It is preferable that the first reference plane S1 is a horizontal plane.

The second reference plane information may be information about the ground of the work site WS (e.g., information about the ground of the work target WT) identified by the controller 50 based on point cloud data input from the site information acquirer 20 to the controller 50 when the cab 14 is placed at the second position. Specifically, for example, the second reference plane information may include information about the second reference plane S2 as follows: The controller 50 may identify a plane corresponding to the ground as the second reference plane S2 based on the point cloud data input from the site information acquirer 20 when the cab 14 is placed at the second position.

Furthermore, the first reference plane information may include information on the angle θ1 of the first reference plane S1 (e.g., the angle θ1 of the first reference plane S1 relative to the horizontal plane), and the second reference plane information may include information on the angle θ2 of the second reference plane S2 (e.g., the angle θ2 of the second reference plane S2 relative to the horizontal plane).

The controller 50 may identify the first reference surface S1 and the second reference surface S2 from the point cloud data using a shape fitting algorithm such as RANSAC (Random sample consensus) or MSAC (M-estimator sample consensus).

The reference position RP does not fluctuate, at least during the time period when position correction control is performed. On the other hand, the first coordinate C1 and the second coordinate C2 are each calculated using the initial relative position information (e.g., the acquirer initial coordinate C0). Therefore, even though the reference position RP does not fluctuate, the first coordinate C1 and the second coordinate C2 have different values. The difference ΔC between the first coordinate C1 and the second coordinate C2 corresponds to the change in the coordinate of the site information acquirer 20 that occurs as the cab 14 rotates from the first position (the initial setting position) to the second position. Furthermore, in the second embodiment, because the cab 14 rotates around the rotation axis A1, the angle θ1 of the first reference plane S1 and the angle θ2 of the second reference plane S2 have different values.

Therefore, the controller 50 may correct the angle of the site information acquirer 20 using the angle θ1 of the first reference plane S1 and the angle θ2 of the second reference plane S2 (or the difference Δθ between them), and may also correct the position of the site information acquirer 20 using the difference ΔC between the first coordinate C1 and the second coordinate C2. Specifically, the controller 50 may calculate the acquirer corrected coordinate C0' by substituting the acquirer initial coordinate C0 and the difference ΔC into a predetermined relational expression set to correct the position of the site information acquirer 20.

The calculated corrected acquirer coordinates C0' are coordinates in the reference coordinate system with the specific position SP as the origin, and are the coordinates of the site information acquirer 20 when the cab 14 is located at the second position. Therefore, the controller 50 can appropriately perform the assist control after the position correction control using the corrected acquirer coordinates C0' in the position correction control, the difference Δθ, and the point cloud data acquired by the site information acquirer 20. In other words, the assist control is appropriately performed for the specified work to be performed when the cab 14 is located at the second position.

FIG. 8 is a flowchart showing the calculation process performed by the controller 50 of the work machine control device 40 according to the second embodiment.

As shown in Figure 7, when the work machine 100 is positioned near the work object WT and the cab 14 is positioned in the initial setting position (first position), the controller 50 acquires the coordinates of the reference position RP (first coordinates C1) and the first reference plane S1 (step S21 in Figure 8).

Specifically, in step S21, with the cab 14 positioned at the first position as the initial setting position, the controller 50 uses the point cloud data input from the site information acquirer 20 to calculate the first coordinate C1 of the reference position RP and the angle θ1 of the first reference plane S1, which is a plane corresponding to the ground surface of the work site WS. The controller 50 then stores the calculated first coordinate C1 and the angle θ1 of the first reference plane S1 (step S22).

Next, the controller 50 controls the operation of the rotation actuator 17 so that the cab 14 rotates (step S23). Specifically, if the initial setting position is the first position, the controller 50 controls the operation of the rotation actuator 17 so that the cab 14 rotates from the first position to the second position.

The second position is the position of the cab 14 when the work machine 100 is performing work at the work site. The second position is determined appropriately depending on various conditions, such as the type of work to be performed at the work site and the specifications of the work machine 100. The second position may be set, for example, based on an input operation by a person involved in the work. The input operation may be, for example, an operation on an input device inside the cab 14, or an operation on an external device that is separate from the work machine 100. The second position may also be a position determined in response to a rotation operation applied by a person involved in the work to the operating device 16 inside the cab 14, or a position determined in response to a rotation operation applied by a person involved in the work to the remote operating device. In this case, the cab 14 continues to rotate while a rotation operation is applied to the operating device 16 or the remote operating device.

Once the rotation of the cab 14 is complete and the cab 14 is positioned at the second position, the controller 50 acquires the coordinates of the reference position RP (second coordinates C2) and the second reference plane S2 (step S24). Specifically, in step S24, with the cab 14 positioned at the second position, the controller 50 uses the point cloud data input from the site information acquirer 20 to calculate the second coordinates C2 of the reference position RP and the angle θ2 of the second reference plane S2, which is a plane corresponding to the ground surface of the work site WS.

Next, the controller 50 compares the angle θ1 of the first reference surface S1 with the angle θ2 of the second reference surface S2 to determine whether a predetermined condition for determining whether angle correction is necessary is met (step S25). The condition for determining whether angle correction is necessary may be, for example, the condition that the angle θ1 of the first reference surface S1 and the angle θ2 of the second reference surface S2 do not match (Δθ = θ1 - θ2 ≠ 0), as described in step S25 of FIG. 8, or the condition that the difference Δθ between the angles θ1 and θ2 is not included in the predetermined allowable range Thθ (|θ1 - θ2| > Thθ).

If the angle correction necessity determination condition is met (YES in step S25), the controller 50 corrects the angle of the site information acquirer 20 using the difference Δθ between angle θ1 and angle θ2 as a correction value (step S26). Specifically, the controller 50 may correct the angle of the site information acquirer 20 by, for example, transforming the point cloud data in the acquirer coordinate system input from the site information acquirer 20 to rotate it by the difference Δθ around the origin of the acquirer coordinate system.

Next, the controller 50 performs the process of step S24 again. That is, the controller 50 acquires the coordinates of the reference position RP (second coordinates C2) and the second reference plane S2 again (step S24). Specifically, in the second execution of step S24, with the cab 14 positioned at the second position, the controller 50 uses the point cloud data input from the site information acquirer 20 to calculate the second coordinates C2 of the reference position RP and the angle θ2' of the second reference plane S2, which is a plane corresponding to the ground surface of the work site WS.

Next, the controller 50 compares the angle θ1 with the angle θ2' and determines whether the angle correction necessity determination condition is met (step S25). The angle θ1 is the angle of the first reference plane S1 stored in step S22, and the angle θ2' is the angle calculated in the second step S24. Therefore, when the angles θ1 and θ2 are compared in the second step S25, the difference Δθ between the angles θ1 and θ2 is smaller than in the first step S25.

Next, if the angle correction necessity determination condition is not met (NO in step S25), the controller 50 performs the process of step S27. Specifically, for example, the controller 50 performs the process of step S27 if the angle θ1 and the angle θ2 are the same (Δθ = 0), or if the difference Δθ is within the allowable range Thθ (|θ1 - θ2| ≦ Thθ).

In step S27, the controller 50 compares the first coordinate C1 and the second coordinate C2 to determine whether the position correction necessity determination condition is met. The position correction necessity determination condition may be, for example, the condition that the first coordinate C1 and the second coordinate C2 do not match (ΔC = C1 - C2 ≠ 0), as shown in step S27 of FIG. 8, or the condition that the difference ΔC between the first coordinate C1 and the second coordinate C2 is not included in a predetermined tolerance range Th (|C1 - C2| > Th).

If the condition for determining whether position correction is necessary is met (YES in step S27), the controller 50 corrects the position of the on-site information acquirer 20 using the difference ΔC between the first coordinate C1 and the second coordinate C2 as a correction value (step S28). Specifically, if the first coordinate C1 is (x1, y1, z1) and the second coordinate C2 is (x2, y2, z2), the difference ΔC is expressed, for example, by the above relational expression (1).

The controller 50 pre-stores the initial coordinates C0 (x0, y0, z0) of the site information acquirer 20 when the cab 14 is positioned at the first position (the initial setting position).

In step S28, the controller 50 obtains the corrected coordinates C0' of the acquirer by correcting the initial coordinates C0 of the acquirer using the difference ΔC. Specifically, for example, the controller 50 may calculate the corrected coordinates C0' (x0', y0', z0') of the acquirer by substituting the initial coordinates C0 and the difference ΔC into the above relational expression (2).

Next, the controller 50 again performs the processing from step S24 onwards. When the controller 50 reaches step S27, it compares the first coordinate C1 with the second coordinate C2 to determine whether the position correction necessity determination condition is met. The first coordinate C1 is calculated using the coordinates stored in step S22, i.e., the acquirer initial coordinate C0 (the initial relative position information), and the second coordinate C2 is calculated using the acquirer corrected coordinate C0'. Therefore, in the comparison between the first coordinate C1 and the second coordinate C2 in the second step S27, the difference ΔC between the first coordinate C1 and the second coordinate C2 is smaller than in the first step S27.

Next, if the condition for determining whether position correction is necessary is not met (NO in step S27), the controller 50 terminates the position correction control. Specifically, for example, the controller 50 may terminate the position correction control if the first coordinate C1 and the second coordinate C2 match (ΔC = 0), or if the difference ΔC is within the allowable range Th (|C1 - C2| ≦ Th).

On the other hand, if the position correction necessity determination condition is also satisfied in the second step S27 (YES in step S27), the controller 50 again corrects the position of the site information acquirer 20 using the difference ΔC between the first coordinate C1 and the second coordinate C2 (step S28). That is, specifically, in the second step S28, for example, the controller 50 may again calculate the acquirer corrected coordinates C0' (x0', y0', z0') by substituting the acquirer initial coordinates C0 and the difference ΔC into the above relational expression (2). This further improves the accuracy of the position correction of the site information acquirer 20.

The controller 50 repeats the processing from step S24 onwards until the condition for determining whether position correction is necessary is no longer met in step S27.

[Modification of the second embodiment]
In the second embodiment shown in Fig. 7, the site information acquirer 20 is attached to the cab 14 that rotates about a rotation axis A1 relative to the machine body, but the site information acquirer 20 may also be attached to a working device 3 (an example of a movable part) that is rotatably supported relative to the machine body. In the specific example of Fig. 7, the site information acquirer 20 is attached to the boom 4 (for example, the underside of the boom 4) that is rotatably supported on the machine body (the swivel frame 11 and the center section 15), as indicated by the dashed-dotted square in Fig. 7.

The controller 50 of the work machine control device 40 according to this modified example of the second embodiment may perform the same control as the controller 50 according to the second embodiment described with reference to Figures 7 and 8, specifically, for example, the position correction control shown in the flowchart of Figure 8.

Furthermore, in a modified example of the second embodiment, instead of correcting the position of the site information acquirer 20 using the difference ΔC between the first coordinate C1 and the second coordinate C2 of the reference position RP, the controller 50 may correct the position of the site information acquirer 20 using the attitude information of the work device 3 input to the controller 50 from the attitude information acquirer 80.

[Other Modifications]
Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments and further includes, for example, the following modified examples.

(A) Modification 1
In the above embodiment, the controller 50 corrects the position of the site information acquirer 20 using the difference ΔC between the first coordinate C1 and the second coordinate C2 of the reference position RP, but the work machine 100 may be equipped with a lifting sensor that detects the degree of elevation of the cab 14 (elevator cab), and the controller 50 may correct the position of the site information acquirer 20 based on the detection results input from the lifting sensor.

The lifting sensor may be, for example, a sensor that detects the attitude (e.g., the angle of the link member) of a link member (not shown) that moves in conjunction with the lifting and lowering of the cab 14 (elevator cab). In this case, the attitude of the link member (the angle of the link member) is a parameter correlated with the position of the site information acquirer 20, the first position information includes a first attitude value (e.g., a first link angle) related to the attitude of the link member input from the sensor when the cab 14 is located at a first position (e.g., the lowest position Pa), and the second position information includes a second attitude value (e.g., a second link angle) related to the attitude of the link member input from the sensor when the cab 14 is located at a second position (e.g., the work position Px). The controller 50 may then correct the coordinates of the site information acquirer 20 using the difference between the first attitude value and the second attitude value.

Furthermore, the elevation sensor may be, for example, a surveying instrument. The surveying instrument can acquire position information correlated to the position of the site information acquirer 20. It is preferable that a reflective member such as a prism is attached to the site information acquirer 20. In this case, the first position information includes position information (e.g., height information) of the site information acquirer 20 input from the surveying instrument when the cab 14 is positioned at a first position (e.g., the lowest position Pa), and the second position information includes position information (e.g., height information) of the site information acquirer 20 input from the surveying instrument when the cab 14 is positioned at a second position (e.g., the work position Px). The controller 50 may then correct the coordinates of the site information acquirer 20 using the difference between the first position information and the second position information.

(B) Modification 2
In the first embodiment, the work machine control device 40 is provided on the work machine 100, but the work machine control device in the present disclosure may also be provided on an external device other than a work machine. Furthermore, in the specific example shown in Fig. 2, the controller 50 of the work machine control device 40 includes a correction controller 51, an operation control controller 52, and an assist data storage device 53, and the work machine 100 is provided with the controller 50, but the work machine 100 may also be provided with some of the functions of the controller 50 of the work machine control device 40 (for example, the functions of the correction controller 51), and the external device 200 may be provided with other parts of the functions of the controller 50 of the work machine control device 40 (for example, the functions of the operation control controller 52). Furthermore, the controller 50 of the work machine control device 40 may be provided with the correction controller 51, and may not be provided with at least one of the operation control controller 52 and the assist data storage device 53.

(C) Modification 3
The automatic driving data does not necessarily have to be stored in the assist data storage device 53, but may be stored in an external device separate from the work machine 100. In this case, the controller 50 may acquire the automatic driving data stored in the external device by wireless or wired communication via a communication device, and perform the assist control using the acquired automatic driving data.

(D) Modification 4
In the above embodiment, the reference position RP is the position of the reference object 60 placed at the work site WS, but is not limited to this. The reference position RP may be, for example, a predetermined position on the machine body. In this case, the machine body is a part that is not linked to the raising/lowering or rotation of the cab 14. Specifically, the machine body may be the undercarriage 1 or a part of the upper rotating body 2 other than the cab 14. The predetermined position may be a position that is set in advance on the undercarriage 1 or a position that is set in advance on a part of the upper rotating body 2 other than the cab 14. For example, a reflective material may be placed at the predetermined position.

Furthermore, the reference position RP may be the position of a reference object 60 supported by the machine body, for example, as shown in FIG. 9. Specifically, the machine body may be the lower traveling body 1, or a part of the upper rotating body 2 other than the cab 14. As in the specific example of FIG. 9, the reference object 60 may be supported by an unillustrated frame of the lower traveling body 1, or may be supported at the rear of the upper rotating body 2 (for example, an outer wall defining the machine room). The reference object 60 may be supported by the machine body via, for example, a rod-shaped support member.

(E) Modification 5
5, step S15 may be omitted. That is, after calculating the second coordinate C2 of the reference position RP in step S14, the controller 50 may correct the position of the site information acquirer 20 using the difference ΔC between the first coordinate C1 and the second coordinate C2 as a correction value in step S16 without performing the process of step S15, and then end the position correction control.

(F) Modification 6
In the above embodiment, the reference coordinate system used when correcting the position of the site information acquirer 20 is a three-dimensional coordinate system, but if, for example, only information regarding coordinates on vertical coordinate axes and information regarding coordinates on front-rear coordinate axes is required for the correction, the reference coordinate system may be a two-dimensional coordinate system (for example, a two-dimensional coordinate system including vertical coordinate axes and front-rear coordinate axes).Furthermore, if, for example, only information regarding coordinates on vertical coordinate axes (height direction) is required for the correction, the reference coordinate system may be a one-dimensional coordinate system (for example, a one-dimensional coordinate system including vertical coordinate axes).

(G) Modification 7
In the above embodiment, the site information acquirer 20 is a three-dimensional position information acquirer configured to acquire three-dimensional position information (e.g., point cloud data) of objects present at a work site, but is not limited to this. The site information acquirer in the present disclosure may be any device that is attached to a movable part that can change its position relative to the machine body and acquires work site information, which is information about the work site, and may be, for example, an imaging device such as a camera that is attached to a movable part such as a cab and captures images of the periphery of the work machine.

[Reference example]
10 is a diagram showing a work machine system equipped with a work machine control device according to a reference example. In this reference example, the work machine system includes a work machine 100 and a site information acquirer 20, and this site information acquirer 20 is not attached to a movable part such as the cab 14 or work implement 3 of the work machine 100, but is located at the work site WS.

In this reference example, for example, when the work machine 100 travels through the work site WS, the relative position between the work machine 100 and the site information acquirer 20 (specifically, the relative position between the specific position SP of the work machine 100 and the site information acquirer 20) changes. In this case, the controller 50 of the work machine control device 40 may correct the position of the site information acquirer 20 using first position information that correlates with the position of the site information acquirer 20 when the work machine 100 is located at its initial position (first position) at the work site WS, and second position information that correlates with the position of the site information acquirer 20 when the work machine 100 is located at a second position (different from the first position) at the work site WS.

In this reference example, each of the first position information and the second position information may be, for example, position information of the work machine 100 included in point cloud data input from the site information acquirer 20 to the controller 50, or may be position information of the work machine 100 included in measurement results input from a measuring device other than the site information acquirer 20 to the controller 50.

As described above, a work machine control device, work machine, external device for a work machine, work machine system, and position correction method are provided that can appropriately control a work machine using work site information acquired by a site information acquisition device.

The work machine control device according to the first aspect is a work machine control device for controlling a work machine that includes a machine main body, a movable part whose position relative to the machine main body can be changed, and a site information acquirer attached to the movable part and that acquires work site information, which is information about the work site. The work machine control device includes a controller that corrects the position of the site information acquirer using first position information that correlates with the position of the site information acquirer when the movable part is located at a first position, and second position information that correlates with the position of the site information acquirer when the movable part is located at a second position different from the first position.

In the work machine control device according to this first aspect, even if the relative position between the site information acquirer attached to the movable part and the work object at the work site changes as the movable part displaces relative to the machine body, the controller corrects the position of the site information acquirer using the first position information and the second position information, thereby appropriately controlling the work machine using the work site information acquired by the site information acquirer.

In a second aspect, it is preferable that the work machine control device according to the first aspect further comprises the following configuration. That is, in the work machine control device according to the second aspect, it is preferable that the controller is configured to identify, as the first position information, first coordinates that are coordinates of a reference position using the work site information acquired by the work site information acquirer when the movable part is placed at the first position, and to identify, as the second position information, second coordinates that are coordinates of the reference position using the work site information acquired by the work site information acquirer when the movable part is placed at the second position. In this second aspect, it is possible to acquire the first position information and the second position information using the work site information acquired by the work site information acquirer when the movable part is placed at the first position and the second position, respectively.

In a third aspect, it is preferable that the work machine control device according to the second aspect further comprises the following configuration. That is, in the work machine control device according to the third aspect, it is preferable that the controller corrects the position of the site information acquirer using the difference between the first coordinates and the second coordinates.

In a fourth aspect, it is preferable that the work machine control device according to the second or third aspect further comprises the following configuration. That is, in the work machine control device according to the fourth aspect, it is preferable that the reference position is the position of a reference object that is an object placed at the work site, a predetermined position on the machine body, or the position of a reference object that is an object supported by the machine body. When the reference object is placed at the work site, it is more preferable that the reference object is placed at a position higher than the ground at the work site. In this fourth aspect, it is possible to easily set the reference position for correcting the position of the work site information acquirer.

In a fifth aspect, it is preferable that the work machine control device according to any one of the second to fourth aspects further comprises the following configuration. That is, in the work machine control device according to the fifth aspect, it is preferable that the site information acquirer is a three-dimensional position information acquirer capable of acquiring three-dimensional position information of the work site, and the controller uses the three-dimensional position information input from the three-dimensional position information acquirer to control the operation of the work machine and perform assist control to assist those involved in the work. In this fifth aspect, the work site information (the three-dimensional position information) acquired by the site information acquirer (the three-dimensional position information acquirer) is used both to identify the first position information and the second position information, and for the assist control. This makes it possible to prevent an increase in devices such as sensors.

In a sixth aspect, it is preferable that the work machine control device according to any one of the first to fifth aspects further comprises the following configuration. That is, in the work machine control device according to the sixth aspect, it is preferable that the movable part is a cab that can be raised and lowered relative to the machine body. In this sixth aspect, even if the cab is a so-called elevator cab, it is possible to attach the site information acquirer to the cab.

A seventh aspect may further include the following configuration in the construction machine control device according to any one of the first to fifth aspects. That is, in the construction machine control device according to the seventh aspect, the movable part may be a cab that is rotatable relative to the machine body. In this seventh aspect, even if the cab is rotatable relative to the machine body, it is possible to attach the site information acquirer to the cab.

In an eighth aspect, it is preferable that the work machine control device according to the seventh aspect further comprises the following configuration. That is, in the work machine control device according to the eighth aspect, it is preferable that the controller corrects the angle of the site information acquirer using first reference plane information, which is information about the ground surface of the work site when the movable part is positioned at the first position, and second reference plane information, which is information about the ground surface of the work site when the movable part is positioned at the second position. In this eighth aspect, since the angle of the site information acquirer can also be corrected, when the site information acquirer is attached to a cab that is rotatable relative to the machine body, the work machine can be controlled more appropriately using the work site information acquired by the site information acquirer.

A ninth aspect may further include the following configuration in the construction machine control device according to any one of the first to fifth aspects. That is, in the construction machine control device according to the ninth aspect, the movable part may be a work device that is rotatable relative to the machine body. In this ninth aspect, it becomes possible to attach the site information acquirer to a work device that is rotatable relative to the machine body.

A work machine according to a tenth aspect comprises a machine body, a movable part whose relative position with respect to the machine body can be changed, a site information acquirer attached to the movable part, and a work machine control device according to any one of the first to ninth aspects. In this work machine according to the tenth aspect, even if the relative position between the site information acquirer attached to the movable part and the work target at the work site changes as the movable part displaces with respect to the machine body, the controller corrects the position of the site information acquirer using the first position information and the second position information, thereby appropriately controlling the work machine using the work site information acquired by the site information acquirer.

An external device for a work machine according to an eleventh aspect includes a work machine control device according to any one of the first to ninth aspects. Even if the relative position between the site information acquirer attached to the movable part and the work target at the work site changes as the movable part displaces relative to the machine body, in the external device for a work machine according to this eleventh aspect, the controller corrects the position of the site information acquirer using the first position information and the second position information, so that the work machine is appropriately controlled using the work site information acquired by the site information acquirer.

A twelfth aspect is a work machine system comprising a work machine and an external device, the work machine system including a work machine control device according to any one of the first to ninth aspects. In the work machine system according to this twelfth aspect, even if the relative position between the site information acquirer attached to the movable part and the work target at the work site changes as the movable part displaces relative to the machine body, the controller corrects the position of the site information acquirer using the first position information and the second position information, thereby appropriately controlling the work machine using the work site information acquired by the site information acquirer.

A position correction method according to a thirteenth aspect is a position correction method for a work machine comprising a machine body, a movable unit capable of changing its position relative to the machine body, and a site information acquirer attached to the movable unit and acquiring work site information, which is information about the work site. The position correction method includes a controller correcting the position of the site information acquirer using first position information that correlates with the position of the site information acquirer when the movable unit is located at a first position, and second position information that correlates with the position of the site information acquirer when the movable unit is located at a second position different from the first position. In this position correction method according to the thirteenth aspect, even if the relative position of the site information acquirer attached to the movable unit and the work object at the work site changes as the movable unit displaces relative to the machine body, the controller corrects the position of the site information acquirer using the first position information and the second position information, thereby allowing the work machine to be appropriately controlled using the work site information acquired by the site information acquirer.

Claims (13)

A work machine control device for controlling a work machine, the work machine control device comprising: a machine main body; a movable part whose position relative to the machine main body can be changed; and a site information acquirer attached to the movable part and which acquires work site information that is information about a work site,
A work machine control device comprising: a controller that makes corrections to the position of the site information acquirer using first position information that correlates with the position of the site information acquirer when the movable part is positioned at a first position, and second position information that correlates with the position of the site information acquirer when the movable part is positioned at a second position different from the first position. The work machine control device according to claim 1, wherein the controller is configured to identify, as the first position information, first coordinates that are coordinates of a reference position using the work site information acquired by the work site information acquirer when the movable part is placed at the first position, and to identify, as the second position information, second coordinates that are coordinates of the reference position using the work site information acquired by the work site information acquirer when the movable part is placed at the second position. The work machine control device described in claim 2, wherein the controller corrects the position of the site information acquisition device using the difference between the first coordinates and the second coordinates. The work machine control device according to claim 2 or 3, wherein the reference position is the position of a reference object that is an object placed at the work site, a predetermined position on the machine body, or the position of a reference object that is an object supported by the machine body. the site information acquirer is a three-dimensional position information acquirer capable of acquiring three-dimensional position information of the work site,
The work machine control device according to any one of claims 2 to 4, wherein the controller uses the three-dimensional position information input from the three-dimensional position information acquirer to control the operation of the work machine and perform assist control to assist people involved in the work. The work machine control device described in any one of claims 1 to 5, wherein the movable part is a cab that can be raised and lowered relative to the machine body. The work machine control device described in any one of claims 1 to 5, wherein the movable part is a cab that is rotatable relative to the machine body. The work machine control device described in claim 7, wherein the controller corrects the angle of the site information acquirer using first reference plane information, which is information about the ground surface of the work site when the movable part is positioned at the first position, and second reference plane information, which is information about the ground surface of the work site when the movable part is positioned at the second position. The work machine control device according to any one of claims 1 to 5, wherein the movable part is a work device that is rotatable relative to the machine body. The machine body,
a movable part whose relative position with respect to the machine body can be changed;
a site information acquirer attached to the movable part;
A work machine comprising: a work machine control device according to any one of claims 1 to 9. An external device for a work machine equipped with the work machine control device described in any one of claims 1 to 9. A work machine system including a work machine and an external device,
The work machine system includes the work machine control device according to any one of claims 1 to 9. A position correction method for a work machine including a machine body, a movable part whose relative position with respect to the machine body can be changed, and a site information acquirer attached to the movable part and which acquires work site information that is information about a work site, the method comprising:
A position correction method including a controller making a correction for the position of the site information acquirer using first position information correlating with the position of the site information acquirer when the movable unit is positioned at a first position, and second position information correlating with the position of the site information acquirer when the movable unit is positioned at a second position different from the first position.