JP7462710B2 - Work machine image display system and work machine image display method - Google Patents

Description

The present invention relates to an image display system for a work machine, a remote control system for a work machine, a work machine, and an image display method for a work machine.

As described in Patent Document 1, technology is known for remotely controlling work machines such as hydraulic excavators.

JP 2004-294067 A

When remotely operating a work machine, if an image from the operator's viewpoint is used, the displayed image is two-dimensional, resulting in a lack of perspective. This makes it difficult to grasp the distance between the work object and the work machine, which can lead to reduced work efficiency. Also, when an operator on board the work machine operates the work machine, depending on the operator's level of skill, it can be difficult to grasp the distance between the work machine and the work object, which can lead to reduced work efficiency.

The present invention aims to prevent a decrease in work efficiency when working with a work machine equipped with a work implement having a working tool.

The present invention is an image display system for a work machine, including an imaging device attached to a work machine equipped with a work implement having a working tool, an attitude detection device that detects the attitude of the work implement, a distance detection device that obtains information on the distance to a work object of the work machine, and a processing device that uses information on the position of the work implement obtained using the attitude of the work implement and information on the position of the work object obtained from the distance information obtained by the distance detection device to generate an image of a portion of the work object facing the work implement that corresponds to the work implement, combines the image with an image of the work object captured by the imaging device, and displays the image on a display device. It is preferable that the processing device generates the image of the portion corresponding to the work implement using the imaging device as a reference.

It is preferable that the line image is a grid having a plurality of first line images and a plurality of second line images that intersect with the plurality of first line images.

It is preferable that the processing device uses the posture of the work tool to determine the area that the work tool occupies in the image of the work object, and removes the obtained area from the information on the shape of the work object.

It is preferable that the work tool is a bucket, and the processing device generates a line image of a portion of the work object that corresponds to the cutting edge of the bucket as an image of the portion of the work object that faces the work tool.

It is preferable that the processing device generates an image of a straight line connecting one end side of the bucket blade tip in the width direction to the work object and an image of a straight line connecting the other end side of the bucket blade tip in the width direction to the work object, combines the images with the image of the work object captured by the imaging device, and displays the images on a display device.

It is preferable that the processing device obtains spatial position information relating to the work tool or the work object and displays it on the display device.

It is preferable that the processing device obtains at least one of the position of the work tool, the orientation of the work tool, the position of the work object, the relative orientation of the work object, the relative distance between the work tool and the work object, and the relative orientation between the work tool and the work object, and displays it on the display device.

It is preferable that the processing device uses information on the position of the work object to generate a line image along the surface of the work object, combine it with the image of the work object, and display it on the display device.

It is preferable that the imaging device, the attitude detection device, and the distance detection device are provided on the work machine, and the processing device and the display device are provided in a facility equipped with an operating device for remotely operating the work machine.

The present invention is an image display system for a work machine that includes a display device and a processing device that, when remotely operating a work machine equipped with a work implement having a work tool, generates an image of a portion of the work object facing the work implement that corresponds to the work implement using the imaging device as a reference, and combines the image with an image of the work object captured by the imaging device and displays the image on the display device, using information on the position of the work implement obtained using the attitude of the work implement and information on the position of the work object obtained from information on the distance to the work implement by a distance detection device equipped on the work machine.

The present invention is a remote control system for a work machine, which includes the image display system for the work machine described above and an operating device for operating the work implement provided on the work machine.

The present invention is a work machine equipped with the image display system for the work vehicle described above.

The present invention can suppress a decrease in work efficiency when working with a work machine equipped with a work implement having a working tool.

FIG. 1 is a diagram showing a work machine image display system and a work machine remote control system according to an embodiment. FIG. 2 is a perspective view showing a hydraulic excavator, which is a work machine according to the embodiment. FIG. 3 is a diagram showing a control system of a hydraulic excavator, which is a work machine according to the embodiment. FIG. 4 is a diagram for explaining a coordinate system in the image display system and the remote control system according to the embodiment. FIG. 5 is a rear view of the hydraulic excavator. FIG. 6 is a diagram for explaining the coordinate systems of the imaging device and the distance detection device. FIG. 7 is a flowchart of an example of control executed by the image display system and the remote control system. FIG. 8 is a diagram showing an imaging device, a distance detection device, and a work target. FIG. 9 is a diagram for explaining an occupied region. FIG. 10 is a diagram showing information on the shape of the work object from which the occupied area has been removed. FIG. 11 is a diagram for explaining an image showing the position of the bucket on the work target. FIG. 12 is a diagram for explaining an image showing the position of the bucket on the work target. FIG. 13 is a diagram for explaining an image showing the position of the bucket on the work target. FIG. 14 is a diagram showing a grid image that is a reference image. FIG. 15 is a diagram showing a grid image that is a reference image. FIG. 16 shows a working image. FIG. 17 is a diagram for explaining a cutting edge position image when a loading shovel type work machine is used. FIG. 18 is a diagram showing a first modified example of the process for obtaining a cutting edge position image. FIG. 19 is a diagram for explaining a second modified example of the process for obtaining a cutting edge position image. FIG. 20 is a diagram for explaining a second modified example of the process for obtaining a cutting edge position image. FIG. 21 is a diagram showing a control system of a hydraulic excavator according to a modified example.

The following describes in detail the form (embodiment) for carrying out the present invention with reference to the drawings.

<Outline of the work machine image display system and the work machine remote control system>
1 is a diagram showing a work machine image display system 100 and a work machine remote control system 101 according to the embodiment. When an operator remotely controls a hydraulic excavator 1, which is a work machine, the work machine image display system 100 (hereinafter referred to as the image display system 100) captures an image of a work target of the hydraulic excavator 1, more specifically, a topographical surface that is the target of work by a work implement 2 provided on the hydraulic excavator 1, that is, a work target WA and a bucket 8 that is a working tool, using an imaging device 19, and displays the obtained image on a display device 52. At this time, the image display system 100 displays, on the display device 52, a work image 69 including an image 68 of the work target WA captured by the imaging device 19, a grid image 65, and an image 60 for indicating the position of the bucket 8 on the work target WA.

The image display system 100 includes an imaging device 19, a posture detection device 32, a distance detection device 20, and a processing device 51. The remote operation system 101 for a work machine (hereinafter referred to as the remote operation system 101 as appropriate) includes an imaging device 19, a posture detection device 32, a distance detection device 20, a work machine control device 27, a display device 52, a processing device 51, and an operation device 53. In the embodiment, the imaging device 19, the posture detection device 32, and the distance detection device 20 of the image display system 100 are provided in the hydraulic excavator 1, and the processing device 51 is provided in the facility 50. The facility 50 is a facility for remotely operating the hydraulic excavator 1 and managing the hydraulic excavator 1. In the embodiment, the imaging device 19, the posture detection device 32, the distance detection device 20, and the work machine control device 27 of the remote operation system 101 are provided in the hydraulic excavator 1, and the display device 52, the processing device 51, and the operation device 53 are provided in the facility 50.

The processing device 51 of the image display system 100 includes a processing unit 51P, a memory unit 51M, and an input/output unit 51IO. The processing unit 51P is a processor such as a CPU (Central Processing Unit). The memory unit 51M is, for example, a RAM (Random Access Memory), a ROM (Read Only Memory), a hard disk drive, a storage device, or a combination of these. The input/output unit 51IO is an interface circuit for connecting the processing device 51 to an external device. In the embodiment, the input/output unit 51IO is connected to a display device 52, an operation device 53, and a communication device 54 as external devices. The external devices connected to the input/output unit 51IO are not limited to these.

The processing device 51 uses information on the position of the bucket 8, which is a working tool, obtained using the attitude of the working machine 2, and information on the position of the work object WA obtained from the distance information determined by the distance detection device 20 to generate an image of the portion of the work object WA facing the bucket 8 that corresponds to the bucket 8, using the imaging device 19 as a reference. The processing device 51 then combines this with the image of the work object WA captured by the imaging device 19 and displays it on the display device 52. The work object WA is the surface on which the working machine 2 of the hydraulic excavator 1 performs work such as excavation or leveling.

The display device 52 may be, for example, a liquid crystal display or a projector, but is not limited to these. The communication device 54 includes an antenna 54A. The communication device 54 communicates with the communication device 25 provided in the hydraulic excavator 1 to obtain information about the hydraulic excavator 1 and transmit information to the hydraulic excavator 1.

The operating device 53 has a left operating lever 53L installed on the operator's left side and a right operating lever 53R located on the operator's right side. The left operating lever 53L and the right operating lever 53R correspond to two-axis operations in forward/backward and left/right directions. For example, forward/backward operation of the right operating lever 53R corresponds to operation of the boom 6 of the work machine 2 provided in the hydraulic excavator 1. Left/right operation of the right operating lever 53R corresponds to operation of the bucket 8 of the work machine 2. Forward/backward operation of the left operating lever 53L corresponds to operation of the arm 7 of the work machine 2. Left/right operation of the left operating lever 53L corresponds to rotation of the upper rotating body 3 of the hydraulic excavator 1.

The amount of operation of the left operating lever 53L and the right operating lever 53R is detected, for example, by a potentiometer and a Hall IC, and the processing device 51 generates a control signal for controlling the solenoid control valve based on these detected values. This signal is sent to the work machine control device 27 via the communication device 54 of the facility 50 and the communication device 25 of the hydraulic excavator 1. The work machine control device 27 controls the solenoid control valve based on the control signal, thereby controlling the work machine 2. The solenoid control valve will be described later.

The processing device 51 acquires input to at least one of the left operating lever 53L and the right operating lever 53R, and generates a command for operating at least one of the work machine 2 and the upper rotating body 3. The processing device 51 transmits the generated command to the communication device 25 of the hydraulic excavator 1 via the communication device 54. The work machine control device 27 provided in the hydraulic excavator 1 acquires the command from the processing device 51 via the communication device 25, and operates at least one of the work machine 2 and the upper rotating body 3 in accordance with the command.

The hydraulic excavator 1 includes a communication device 25, a work machine control device 27, a posture detection device 32, an image capture device 19, a distance detection device 20, antennas 21 and 22, and a global position calculation device 23. The work machine control device 27 controls the work machine 2. The communication device 25 is connected to the antenna 24 and communicates with a communication device 54 provided in the facility 50. The work machine control device 27 controls the work machine 2 and the upper rotating body 3. The posture detection device 32 detects the posture of at least one of the work machine 2 and the hydraulic excavator 1. The image capture device 19 is attached to the hydraulic excavator 1 and captures an image of the work object WA. The distance detection device 20 obtains information on the distance from a predetermined position of the hydraulic excavator 1 to the work object WA. The antennas 21 and 22 receive radio waves from a positioning satellite 200. The global position calculation device 23 obtains the global positions of the antennas 21 and 22, i.e., the positions in the global coordinate system, using the radio waves received by the antennas 21 and 22.

<Overall configuration of hydraulic excavator 1>
FIG. 2 is a perspective view showing a hydraulic excavator 1 which is a work machine according to the embodiment. The hydraulic excavator 1 has a vehicle body 1B as a main body and a working machine 2. The vehicle body 1B has an upper rotating body 3 which is a rotating body and a traveling device 5 which is a traveling body. The upper rotating body 3 accommodates devices such as an engine and a hydraulic pump which are a power generating device inside an engine room 3EG. In the embodiment, the hydraulic excavator 1 uses an internal combustion engine such as a diesel engine as the engine which is the power generating device, but the power generating device is not limited to an internal combustion engine. The power generating device of the hydraulic excavator 1 may be, for example, a so-called hybrid type device which combines an internal combustion engine, a generator motor, and an electricity storage device. Moreover, the power generating device of the hydraulic excavator 1 may be a device which does not have an internal combustion engine and which combines an electricity storage device and a generator motor.

The upper rotating body 3 has a cab 4. The cab 4 is installed at the other end of the upper rotating body 3. In other words, the cab 4 is installed on the opposite side to the side where the engine room 3EG is located. A handrail 9 is attached above the upper rotating body 3.

The traveling device 5 carries the upper rotating body 3. The traveling device 5 has tracks 5a, 5b. The traveling device 5 is driven by one or both of hydraulic motors 5c provided on the left and right. The hydraulic excavator 1 travels as the tracks 5a, 5b of the traveling device 5 rotate. The work machine 2 is attached to the side of the driver's cab 4 of the upper rotating body 3.

The hydraulic excavator 1 may be equipped with tires instead of the tracks 5a, 5b, and may be equipped with a travel device that can travel by transmitting the driving force of the engine to the tires via a transmission. An example of a hydraulic excavator 1 of this type is a wheeled hydraulic excavator. The hydraulic excavator 1 may also be equipped with a travel device having such tires, and may further be equipped with a working machine attached to the vehicle body (main body), and may be, for example, a backhoe loader having a structure that does not include the upper rotating body 3 and its rotating mechanism as shown in FIG. 1. In other words, a backhoe loader is equipped with a working machine attached to the vehicle body, and is equipped with a travel device that constitutes part of the vehicle body.

The side of the upper rotating body 3 where the work machine 2 and the driver's cab 4 are located is the front, and the side where the engine room 3EG is located is the rear. The fore-and-aft direction of the upper rotating body 3 is the x-direction. The left side facing the front is the left of the upper rotating body 3, and the right side facing the front is the right of the upper rotating body 3. The left-right direction of the upper rotating body 3 is also called the width direction or y-direction. In the hydraulic excavator 1 or vehicle body 1B, the traveling gear 5 side is the bottom relative to the upper rotating body 3, and the upper rotating body 3 side is the top relative to the traveling gear 5. The up-down direction of the upper rotating body 3 is the z-direction. When the hydraulic excavator 1 is installed on a horizontal plane, the bottom is the vertical direction, i.e., the side in the direction of gravity, and the top is the opposite side to the vertical direction.

The work machine 2 has a boom 6, an arm 7, a bucket 8 as a working tool, a boom cylinder 10, an arm cylinder 11, and a bucket cylinder 12. The base end of the boom 6 is rotatably attached to the front of the vehicle body 1B via a boom pin 13. The base end of the arm 7 is rotatably attached to the tip of the boom 6 via an arm pin 14. A bucket 8 is attached to the tip of the arm 7 via a bucket pin 15. The bucket 8 rotates around the bucket pin 15. The bucket 8 has multiple blades 8B attached to the side opposite the bucket pin 15. The blade tip 8T is the tip of the blade 8B.

The bucket 8 does not have to have multiple blades 8B. In other words, it may be a bucket that does not have the blade 8B as shown in FIG. 2, and the cutting edge is formed in a straight shape by a steel plate. The work machine 2 may be equipped with, for example, a tilt bucket with a single blade. A tilt bucket is a bucket that is equipped with a bucket tilt cylinder and tilts left and right, so that even if the hydraulic excavator is on a slope, the bucket can be shaped into a free shape on a slope or flat ground, and the ground can be leveled, and it can also perform compaction work using a bottom plate. In addition, the work machine 2 may be equipped with a slope bucket or a rock-cutting attachment equipped with a rock-cutting tip as a working tool instead of the bucket 8.

The boom cylinder 10, arm cylinder 11, and bucket cylinder 12 shown in FIG. 2 are hydraulic cylinders that are each driven by the pressure of hydraulic oil discharged from a hydraulic pump. The boom cylinder 10 drives the boom 6 to raise and lower it. The arm cylinder 11 drives the arm 7 to rotate it around the arm pin 14. The bucket cylinder 12 drives the bucket 8 to rotate it around the bucket pin 15.

Antennas 21, 22 and antenna 24 are attached to the upper part of the upper rotating body 3. The antennas 21, 22 are used to detect the current position of the hydraulic excavator 1. The antennas 21, 22 are electrically connected to a global position calculation device 23 shown in FIG. 3. The global position calculation device 23 is a position detection device that detects the position of the hydraulic excavator 1. The global position calculation device 23 detects the current position of the hydraulic excavator 1 using RTK-GNSS (Real Time Kinematic - Global Navigation Satellite Systems, GNSS stands for Global Navigation Satellite System). In the following description, the antennas 21, 22 are appropriately referred to as GNSS antennas 21, 22. Signals corresponding to the GNSS radio waves received by the GNSS antennas 21, 22 are input to the global position calculation device 23. The global position calculation device 23 determines the installation positions of the GNSS antennas 21, 22 in the global coordinate system. An example of a global navigation satellite system is the Global Positioning System (GPS), but the global navigation satellite system is not limited to this.

As shown in FIG. 2, the GNSS antennas 21, 22 are preferably installed on the upper rotating body 3, at both ends separated in the left-right direction, i.e., in the width direction, of the hydraulic excavator 1. In the embodiment, the GNSS antennas 21, 22 are attached to handrails 9 attached to both sides in the width direction of the upper rotating body 3. The position at which the GNSS antennas 21, 22 are attached to the upper rotating body 3 is not limited to the handrails 9, but it is preferable to install the GNSS antennas 21, 22 as far apart as possible, as this improves the detection accuracy of the current position of the hydraulic excavator 1. In addition, the GNSS antennas 21, 22 are preferably installed in positions that do not obstruct the operator's view as much as possible.

The imaging device 19 captures an image of the work object WA shown in FIG. 1, and the distance detection device 20 determines the distance from itself (a predetermined position of the hydraulic excavator 1) to the work object WA, so it is preferable to obtain information from as wide an area of the work object WA as possible. For this reason, in the embodiment, the antenna 24, imaging device 19, and distance detection device 20 are installed above the driver's cab 4 of the upper rotating body 3. The location where the imaging device 19 and distance detection device 20 are installed is not limited to above the driver's seat 4. For example, the imaging device 19 and distance detection device 20 may be installed inside and above the driver's cab 4.

The imaging device 19 has an imaging surface 19L facing forward of the upper rotating body 3. The distance detection device 20 has a detection surface 20L facing forward of the upper rotating body 3. In the embodiment, the imaging device 19 is a monocular camera equipped with an image sensor such as a CCD (Charge Coupled Device) image sensor or a CMOS (Complementary Metal Oxide Semiconductor) image sensor. In the embodiment, the distance detection device 20 is a three-dimensional laser range finder or a distance sensor. The imaging device 19 and the distance detection device 20 are not limited to these. For example, instead of the imaging device 19 and the distance detection device 20, a device having both a function of acquiring an image of the work object WA and a function of determining the distance to the work object WA may be used. An example of such a device is a stereo camera.

<Control system of hydraulic excavator 1>
3 is a diagram showing a control system 1S of a hydraulic excavator 1 which is a work machine according to the embodiment. The control system 1S includes a communication device 25, a sensor controller 26, a work machine control device 27, an imaging device 19, a distance detection device 20, a global position calculation device 23, an attitude detection device 32, an IMU (Inertial Measurement Unit) 33, and a hydraulic system 36. The communication device 25, the sensor controller 26, and the work machine control device 27 are connected by a signal line 35. With this structure, the communication device 25, the sensor controller 26, and the work machine control device 27 can exchange information with each other via the signal line 35. An example of the signal line that transmits information within the control system 1S is an in-vehicle signal line such as a CAN (Controller Area Network).

The sensor controller 26 has a processor such as a CPU (Central Processing Unit) and storage devices such as RAM and ROM. The sensor controller 26 receives the detection values of the global position calculation device 23, information on the image captured by the imaging device 19, the detection values of the distance detection device 20, the detection values of the attitude detection device 32, and the detection values of the IMU 33. The sensor controller 26 transmits the input detection values and image information to a processing device 51 of the facility 50 shown in FIG. 1 via a signal line 35 and a communication device 25.

The work machine control device 27 has a processor such as a CPU (Central Processing Unit) and storage devices such as a RAM (Random Access Memory) and a ROM (Read Only Memory). The work machine control device 27 acquires commands for operating at least one of the work machine 2 and the upper rotating body 3, generated by the processing device 51 of the facility 50, via the communication device 25. The work machine control device 27 controls the solenoid control valve 28 of the hydraulic system 36 based on the acquired commands.

The hydraulic system 36 includes an electromagnetic control valve 28, a hydraulic pump 29, and hydraulic actuators such as the boom cylinder 10, the arm cylinder 11, the bucket cylinder 12, and the swing motor 30. The hydraulic pump 29 is driven by an engine 31 and discharges hydraulic oil for operating the hydraulic actuators. The work machine control device 27 controls the flow rate of hydraulic oil supplied to the boom cylinder 10, the arm cylinder 11, the bucket cylinder 12, and the swing motor 30 by controlling the electromagnetic control valve 28. In this way, the work machine control device 27 controls the operation of the boom cylinder 10, the arm cylinder 11, the bucket cylinder 12, and the swing motor 30.

The sensor controller 26 acquires the detection values of the first stroke sensor 16, the second stroke sensor 17, and the third stroke sensor 18. The first stroke sensor 16 is provided on the boom cylinder 10, the second stroke sensor 17 on the arm cylinder 11, and the third stroke sensor 18 on the bucket cylinder 12.

The first stroke sensor 16 detects the boom cylinder length, which is the length of the boom cylinder 10, and outputs it to the sensor controller 26. The second stroke sensor 17 detects the arm cylinder length, which is the length of the arm cylinder 11, and outputs it to the sensor controller 26. The third stroke sensor 18 detects the bucket cylinder length, which is the length of the bucket cylinder 12, and outputs it to the sensor controller 26.

Once the boom cylinder length, arm cylinder length, and bucket cylinder length are determined, the posture of the work machine 2 is determined. Therefore, the first stroke sensor 16, second stroke sensor 17, and third stroke sensor 18 that detect these correspond to the posture detection device 32 that detects the posture of the work machine 2. The posture detection device 32 is not limited to the first stroke sensor 16, second stroke sensor 17, and third stroke sensor 18, and may be an angle detector.

The sensor controller 26 calculates the inclination angle of the boom 6 in the direction perpendicular to the horizontal plane (z-axis direction) in the local coordinate system, which is the coordinate system of the hydraulic excavator 1, from the boom cylinder length detected by the first stroke sensor 16. The work machine control device 27 calculates the inclination angle of the arm 7 relative to the boom 6 from the arm cylinder length detected by the second stroke sensor 17. The work machine control device 27 calculates the inclination angle of the bucket 8 relative to the arm 7 from the bucket cylinder length detected by the third stroke sensor 18. The inclination angles of the boom 6, arm 7, and bucket 8 are information indicating the posture of the work machine 2. That is, the sensor controller 26 obtains information indicating the posture of the work machine 2. The sensor controller 26 transmits the calculated inclination angle to the processing device 51 of the facility 50 shown in FIG. 1 via the signal line 35 and the communication device 25.

The GNSS antenna 21 receives position P1, which indicates its own position, from the positioning satellite. The GNSS antenna 22 receives position P2, which indicates its own position, from the positioning satellite. The GNSS antennas 21 and 22 receive positions P1 and P2 at a frequency of, for example, 10 Hz. Positions P1 and P2 are information on the positions where the GNSS antennas are installed in the global coordinate system. Signals corresponding to the GNSS radio waves received by the GNSS antennas 21 and 22, i.e., positions P1 and P2, are input to the global position calculation device 23. The GNSS antennas 21 and 22 output positions P1 and P2 to the global position calculation device 23 each time they receive them.

The global position calculation device 23 has a processor such as a CPU and storage devices such as a RAM and a ROM. The global position calculation device 23 detects the positions P1 and P2 of the GNSS antennas 21 and 22 in the global coordinate system at a frequency of, for example, 10 Hz, and outputs the positions P1 and P2 to the sensor controller 26 as reference position information Pga1 and Pga2. In the embodiment, the global position calculation device 23 obtains the azimuth angle of the hydraulic excavator 1, more specifically the yaw angle which is the azimuth angle of the upper rotating body 3, from the two acquired positions P1 and P2, and outputs the obtained yaw angle to the sensor controller 26. The sensor controller 26 transmits the acquired reference position information Pga1 and Pga2 and the yaw angle to the processing device 51 of the facility 50 shown in FIG. 1 via the signal line 35 and the communication device 25.

The IMU 33 detects the movement and attitude of the hydraulic excavator 1. The movement of the hydraulic excavator 1 includes at least one of the movement of the upper rotating body 3 and the movement of the traveling gear 5. The attitude of the hydraulic excavator 1 can be represented by the roll angle, pitch angle, and yaw angle of the hydraulic excavator 1. In the embodiment, the IMU 33 detects and outputs the angular velocity and acceleration of the hydraulic excavator 1.

<About the coordinate system>
FIG. 4 is a diagram for explaining the coordinate systems in the image display system 100 and the remote operation system 101 according to the embodiment. FIG. 5 is a rear view of the hydraulic excavator 1. FIG. 6 is a diagram for explaining the coordinate systems of the imaging device and the distance detection device. In the image display system 100 and the remote operation system 101, there are a global coordinate system, a local coordinate system, a coordinate system of the imaging device 19, and a coordinate system of the distance detection device 20. In the embodiment, the global coordinate system is, for example, a coordinate system in the GNSS. The global coordinate system is a three-dimensional coordinate system represented by (X, Y, Z) based on a reference position PG of, for example, a reference pile 80 that is installed in the work area GA of the hydraulic excavator 1. As shown in FIG. 5, the reference position PG is located at, for example, the tip 80T of the reference pile 80 installed in the work area GA.

The local coordinate system is a three-dimensional coordinate system represented by (x, y, z) with the hydraulic excavator 1 as the reference. In the embodiment, the origin position PL of the local coordinate system is the intersection of the z axis, which is the central axis of rotation of the upper rotating body 3, and a plane perpendicular to the z axis within the swing circle of the upper rotating body 3, but is not limited to this. The plane perpendicular to the z axis within the swing circle can be a plane passing through the center of the swing circle in the z-axis direction.

In the embodiment, the coordinate system of the imaging device 19 is a three-dimensional coordinate system represented by (Xc, Yc, Zc) with the center of the light receiving surface 19P of the imaging element 19RC as the origin PC, as shown in Figure 6. In the embodiment, the coordinate system of the distance detection device 20 is a three-dimensional coordinate system represented by (Xd, Yd, Zd) with the center of the light receiving surface 20P of the distance detection element 20RC as the origin PD, as shown in Figure 6.

<Posture of hydraulic excavator 1>
As shown in Fig. 5, the inclination angle θ4 of the upper rotating body 3 in the left-right direction, i.e., the width direction, is the roll angle of the hydraulic excavator 1, the inclination angle θ5 of the upper rotating body 3 in the front-rear direction is the pitch angle of the hydraulic excavator 1, and the angle of the upper rotating body 3 around the z-axis is the yaw angle of the hydraulic excavator 1. The roll angle is obtained by integrating the angular velocity around the x-axis detected by the IMU 33 over time, the pitch angle is obtained by integrating the angular velocity around the y-axis detected by the IMU 33 over time, and the yaw angle is obtained by integrating the angular velocity around the z-axis detected by the IMU 33 over time. The angular velocity around the z-axis is the swing angular velocity ω of the hydraulic excavator 1. That is, the yaw angle of the hydraulic excavator 1, more specifically, of the upper rotating body 3, is obtained by integrating the swing angular velocity ω over time.

The acceleration and angular velocity detected by the IMU 33 are output to the sensor controller 26 as operation information. The sensor controller 26 performs processing such as filtering and integration on the operation information acquired from the IMU 33 to obtain the inclination angle θ4, which is the roll angle, the inclination angle θ5, which is the pitch angle, and the yaw angle. The sensor controller 26 transmits the obtained inclination angle θ4, inclination angle θ5, and yaw angle as information related to the attitude of the hydraulic excavator 1 to the processing device 51 of the facility 50 shown in FIG. 1 via the signal line 35 and communication device 25 shown in FIG. 3.

As described above, the sensor controller 26 obtains information indicating the attitude of the work machine 2. Specifically, the information indicating the attitude of the work machine 2 is the inclination angle θ1 of the boom 6 in the direction perpendicular to the horizontal plane in the local coordinate system (z-axis direction), the inclination angle θ2 of the arm 7 relative to the boom 6, and the inclination angle θ3 of the bucket 8 relative to the arm 7. The processing device 51 of the facility 50 shown in FIG. 1 calculates the position P4 of the blade tip 8T of the bucket 8 (hereinafter referred to as the blade tip position) from the information indicating the attitude of the work machine 2 obtained from the sensor controller 26 of the hydraulic excavator 1, i.e., the inclination angles θ1, θ2, and θ3.

The memory unit 51M of the processing device 51 stores data of the working machine 2 (hereinafter, appropriately referred to as working machine data). The working machine data includes the length L1 of the boom 6, the length L2 of the arm 7, and the length L3 of the bucket 8. As shown in FIG. 4, the length L1 of the boom 6 corresponds to the length from the boom pin 13 to the arm pin 14. The length L2 of the arm 7 corresponds to the length from the arm pin 14 to the bucket pin 15. The length L3 of the bucket 8 corresponds to the length from the bucket pin 15 to the blade tip 8T of the bucket 8. The blade tip 8T is the tip of the blade 8B shown in FIG. 2. The working machine data also includes information on the position up to the boom pin 13 relative to the origin position PL of the local coordinate system. The processing device 51 can determine the blade tip position P4 relative to the origin position PL using the lengths L1, L2, L3, the inclination angles θ1, θ2, θ3, and the origin position PL. In the embodiment, the processing device 51 of the facility 50 determines the cutting edge position P4, but the sensor controller 26 of the hydraulic excavator 1 may determine the cutting edge position P4 and transmit it to the processing device 51 of the facility 50.

<Example of Control Executed by Image Display System 100 and Remote Control System 101>
Fig. 7 is a flowchart of an example of control executed by the image display system 100 and the remote control system 101. Fig. 8 is a diagram showing the image capturing device 19, the distance detecting device 20, and the work object WA.

In step S101, the sensor controller 26 shown in FIG. 3 acquires information about the hydraulic excavator 1. The information about the hydraulic excavator 1 is information obtained from the imaging device 19, the distance detection device 20, the global position calculation device 23, the attitude detection device 32, and the IMU 33. As shown in FIG. 8, the imaging device 19 captures an image of the work object WA within the imaging range TA to obtain an image of the work object WA. The distance detection device 20 detects the distance Ld from the distance detection device 20 to the work object WA and other objects present within the detection range MA. The global position calculation device 23 obtains reference position information Pga1, Pga2 corresponding to the positions P1, P2 of the GNSS antennas 21, 22 in the global coordinate system. The attitude detection device 32 detects the boom cylinder length, the arm cylinder length, and the bucket cylinder length. The IMU 33 detects the attitude of the hydraulic excavator 1, more specifically, the roll angle θ4, the pitch angle θ5, and the yaw angle of the upper rotating body 3.

In step S102, the image display system 100 and the processing device 51 of the remote operation system 101 acquire information about the hydraulic excavator 1 from the sensor controller 26 of the hydraulic excavator 1 via the communication device 25 of the hydraulic excavator 1 and the communication device 54 connected to the processing device 51.

The information of the hydraulic excavator 1 that the processing device 51 acquires from the sensor controller 26 includes an image of the work object WA captured by the imaging device 19, information on the distance from the distance detection device 20 to the work object WA detected by the distance detection device 20, information on the attitude of the work machine 2 equipped on the hydraulic excavator 1 detected by the attitude detection device 32, reference position information Pga1, Pga2, and information on the attitude of the hydraulic excavator 1.

The information on the distance from the distance detection device 20 to the work object WA includes the distance Ld to the work object WA or object OB present within the detection range MA, and the information on the orientation of the position Pd corresponding to the distance Ld. In FIG. 8, the distance Ld is shown as the distance to the work object WA. The information on the orientation of the position Pd is the orientation of the position Pd when the distance detection device 20 is used as the reference, and is the angle with respect to each axis Xd, Yd, Zd of the coordinate system of the distance detection device 20. The information on the attitude of the work machine 2 acquired by the processing device 51 is the inclination angles θ1, θ2, θ3 of the work machine 2 calculated by the sensor controller 26 using the boom cylinder length, arm cylinder length, and bucket cylinder length. The information on the attitude of the hydraulic excavator 1 is the roll angle θ4, pitch angle θ5, and yaw angle of the hydraulic excavator 1, more specifically, the upper rotating body 3.

The processing device 51 determines the blade tip position P4 of the bucket 8 using the tilt angles θ1, θ2, and θ3 of the work machine 2 acquired from the sensor controller 26, and the length L1 of the boom 6, the length L2 of the arm 7, and the length L3 of the bucket 8 stored in the memory unit 51M. The blade tip position P4 of the bucket 8 is a set of coordinates in the local coordinate system (x, y, z) of the hydraulic excavator 1.

Proceeding to step S103, the processing device 51 converts the distance Ld to the work object WA into position information using the information on the distance to the work object WA. The position information is the coordinates of the position Pd in the coordinate system (Xd, Yd, Zd) of the distance detection device 20. In step S103, all distances Ld detected by the distance detection device 20 within the detection range MA are converted into position information. The processing device 51 converts the distance Ld into position information using the distance Ld and the information on the direction of the position Pd corresponding to the distance Ld. In step S103, the distance to the object OB present within the detection range MA is also converted into position information, similar to the distance Ld to the work object WA. By the processing of step S103, information on the position information of the work object WA within the detection range MA is obtained. Information on the shape of the work object WA can be obtained from the information on the position information of the work object WA.

The position information and shape information of the work object WA are a set of coordinates of the position Pd in the coordinate system (Xd, Yd, Zd) of the distance detection device 20. The processing device 51 converts the shape information of the work object WA into values in the coordinate system (Xc, Yc, Zc) of the imaging device 19, and then converts it into values in the local coordinate system (x, y, z) of the hydraulic excavator 1.

In step S104, the processing device 51 converts the information on the position of the work object WA, the blade tip position P4 of the bucket 8, and the reference position information Pga1, Pga2 acquired from the sensor controller 26 of the hydraulic excavator 1 into a global coordinate system (X, Y, Z). In converting to the global coordinate system (X, Y, Z), the processing device 51 generates a rotation matrix using the roll angle θ4, pitch angle θ5, and yaw angle of the hydraulic excavator 1 acquired from the sensor controller 26. Using the generated rotation matrix, the processing device 51 converts the information on the position of the work object WA, the blade tip position P4 of the bucket 8, and the reference position information Pga1, Pga2 into the global coordinate system (X, Y, Z). Next, the process proceeds to step S105, where the processing device 51 determines the occupied area.

Figure 9 is a diagram illustrating the occupied area SA. The occupied area SA is the area that the work machine 2 occupies within the information on the shape of the work object WA. In the example shown in Figure 9, a part of the bucket 8 of the work machine 2 is within the detection range MA of the distance detection device 20, and is between the distance detection device 20 and the work object WA. For this reason, the distance detection device 20 detects the distance to the bucket 8, not the distance to the work object WA, for the part of the occupied area SA. In the embodiment, the processing device 51 removes the part of the occupied area SA from the information on the shape of the work object WA obtained in step S103.

The processing device 51 stores, for example, in the memory unit 51M, at least one of the position and posture information detected by the distance detection device 20 according to at least one of the position and posture of the bucket 8. In this embodiment, such information is included in the posture of the working machine 2 of the hydraulic excavator 1. The posture of the working machine 2 can be obtained using the inclination angles θ1, θ2, θ3 of the working machine 2, the length L1 of the boom 6, the length L2 of the arm 7, and the length L3 of the bucket 8, and, if necessary, the posture of the hydraulic excavator 1. The processing device 51 compares the data detected by the distance detection device 20 with the information stored in the memory unit 51M, and if the two match, it can determine that the bucket 8 has been detected. By performing such processing using the posture of the working machine 2, the processing device 51 does not use information on the bucket 8 of the occupied area SA when generating the grid image 65 shown in FIG. 1, so that the grid image 65 can be generated accurately.

Processing using the attitude of the work machine 2 to remove portions of the occupied area SA may be performed by the following method. Information on at least one of the position and attitude of the bucket 8 in the global coordinate system, which is included in the attitude of the work machine 2, can be obtained from the tilt angles θ1, θ2, θ3 of the work machine 2, the length L1 of the boom 6, the length L2 of the arm 7, and the length L3 of the bucket 8. In steps S103 and S104, information on the shape of the work object WA in the global coordinate system is obtained. In step S106, the processing device 51 removes the area obtained by projecting the position of the bucket 8 onto the information on the shape of the work object WA as the occupied area SA from the shape of the work object WA.

Figure 10 is a diagram showing information on the shape of the work object WA with the occupied area removed. The information on the shape of the work object WA, IMWA, is a set of coordinates Pgd (X, Y, Z) in the global coordinate system (X, Y, Z). The occupied area IMBA has no coordinate information due to the processing in step S106. Next, the process proceeds to step S107, where the processing device 51 generates an image showing the position of the bucket 8. The image showing the position of the bucket 8 is an image of the part of the work object WA that corresponds to the bucket 8.

Figures 11 to 13 are diagrams for explaining an image showing the position of the bucket 8 on the work object WA. In the embodiment, the image showing the position of the bucket 8 is an image showing the position of the cutting edge 8T of the bucket 8 on the work object WA. Hereinafter, the image showing the position of the cutting edge 8T of the bucket 8 is appropriately referred to as a cutting edge position image. As shown in Figure 11, the cutting edge position image is an image defined by the position Pgt (X, Y, Z) of the surface WAP of the work object WA when the cutting edge 8T is projected onto the work object WA in the vertical direction, i.e., the direction in which gravity acts. The vertical direction is the Z direction in the global coordinate system (X, Y, Z), which is perpendicular to the X and Y directions.

As shown in FIG. 12, the line image formed along the surface WAP of the work object WA between the first position Pgt1 (X1, Y1, Z1) and the second position Pgt2 (X2, Y2, Z2) of the surface WAP of the work object WA is the cutting edge position image 61. The first position Pgt1 (X1, Y1, Z1) is the intersection point between the surface WAP of the work object WA and a straight line LV1 extending vertically from the outer position Pgb1 of the blade 8B at one end 8Wt1 side of the width direction Wb of the bucket 8. The second position Pgt2 (X2, Y2, Z2) is the intersection point between the surface WAP of the work object WA and a straight line LV2 extending vertically from the outer position Pgb2 of the blade 8B at the other end 8Wt2 side of the width direction Wb of the bucket 8. The width direction Wb of the bucket 8 is the direction in which the multiple blades 8B are arranged.

The processing device 51 obtains straight lines LV1 and LV2 extending vertically from positions Pgb1 and Pgb2 of the bucket 8. Next, the processing device 51 obtains a first position Pgt1 (X1, Y1, Z1) and a second position Pgt2 (X2, Y2, Z2) from the obtained straight lines LV1 and LV2 and information on the shape of the work object WA. The processing device 51 then determines the set of positions Pgt of the surface WAP of the work object WA when the straight line connecting the first position Pgt1 and the second position Pgt2 is projected onto the surface WAP of the work object WA as the cutting edge position image 61.

In the embodiment, the processing device 51 generates a first straight line image 62, which is an image of a straight line LV1 connecting the position Pgb1 and the first position Pgt1 (X1, Y1, Z1), and a second straight line image 63, which is an image of a straight line LV2 connecting the position Pgb2 and the second position Pgt2 (X2, Y2, Z2). Next, the processing device 51 converts the cutting edge position image 61, the first straight line image 62, and the second straight line image 63 into images based on the imaging device 19, i.e., images from the viewpoint of the imaging device 19.

As shown in FIG. 13, the image at the viewpoint of the imaging device 19 is an image of the blade tip position image 61, the first straight line image 62, and the second straight line image 63 when viewed from the origin Pgc (Xc, Yc, Zc) of the imaging device in the global coordinate system (X, Y, Z). The origin Pgc (Xc, Yc, Zc) of the imaging device is the coordinate obtained by converting the center of the light receiving surface 19P of the imaging element 19RC of the imaging device 19, i.e., the origin PC, into the global coordinate system (X, Y, Z).

The cutting edge position image 61, the first straight line image 62, and the second straight line image 63 are images in a three-dimensional space, but the image from the viewpoint of the imaging device 19 is a two-dimensional image. Therefore, the processing device 51 executes a perspective projection transformation to project the cutting edge position image 61, the first straight line image 62, and the second straight line image 63 defined in three-dimensional space, i.e., the global coordinate system (X, Y, Z), onto a two-dimensional surface. The cutting edge position image 61, the first straight line image 62, and the second straight line image 63 converted into images from the viewpoint of the imaging device 19 will be referred to as the tool guide image 60 below as appropriate.

14 and 15 are diagrams showing a lattice image 65, which is a reference image. After the work tool guide image 60 is generated, the process proceeds to step S108, where the processing device 51 generates a lattice image 65, which is a reference image. The lattice image 65 is a line image along the surface WAP of the work object WA using information on the position of the work object WA. The lattice image 65 is a lattice including a plurality of first line images 66 and a plurality of second line images 67 intersecting with the plurality of first line images 66. In the embodiment, the first line image 66 is, for example, a line image that extends parallel to the X direction in the global coordinate system (X, Y, Z) and is arranged in the Y direction. The first line image 66 may be a line image that extends parallel to the front-rear direction of the upper rotating body 3 of the hydraulic excavator 1 in the global coordinate system (X, Y, Z) and is arranged in the width direction of the upper rotating body 3.

The grid image 65 is generated using information on the position of the work object WA, more specifically, the position Pgg (X, Y, Z) of the surface WAP. The intersection of the first line image 66 and the second line image 67 is the position Pgg (X, Y, Z). As shown in FIG. 15, the first line image 66 and the second line image 67 are defined in the global coordinate system (X, Y, Z), and therefore contain three-dimensional information. In the embodiment, the multiple first line images 66 are arranged at equal intervals, and the multiple second line images 67 are arranged at equal intervals. The interval between adjacent first line images 66 and the interval between adjacent second line images 67 are equal.

The lattice image 65 is an image in which the first line image 66 and the second line image 67 generated using the position Pgg (X, Y, Z) of the surface WAP are converted into an image from the viewpoint of the imaging device 19. After generating the first line image 66 and the second line image 67, the processing device 51 converts these into an image from the viewpoint of the imaging device 19 to generate the lattice image 65. By converting the first line image 66 and the second line image 67 into an image from the viewpoint of the imaging device 19, the lattice image 65, which is equally spaced in the horizontal plane, can be displayed by being deformed to match the shape of the work object WA in order to assist with the absolute distance of the work object WA.

Next, in step S109, the processing device 51 removes the above-mentioned occupancy area SA from the generated tool guide image 60 and the grid image 65, which is the reference image. In step S109, the processing device 51 converts the occupancy area SA into an image from the viewpoint of the imaging device 19, and removes it from the tool guide image 60 and the grid image 65, which is the reference image. In an embodiment, the processing device 51 may remove the occupancy area SA before being converted into the image from the viewpoint of the imaging device 19 from the cutting edge position image 61, the first straight line image 62, and the second straight line image 63 before being converted into the image from the viewpoint of the imaging device 19, and from the first line image 66 and the second line image 67 before being converted into the image from the viewpoint of the imaging device 19.

Figure 16 is a diagram showing a work image 69. In step S110, the processing device 51 generates a work image 69 by combining the work tool guide image 60 from which the occupied area SA has been removed, the lattice image 65, and an image 68 of the work object WA captured by the imaging device 19. In step S111, the processing device 51 displays the generated work image 68 on the display device 52. The work image 69 is an image in which the lattice image 65 and the work tool guide image 60 are displayed on the image 68 of the work object WA.

Since the lattice image 65 is a lattice that follows the surface WAP of the work object WA, the operator of the hydraulic excavator 1 can grasp the position of the work object WA by referring to the lattice image 65. For example, the operator can grasp the depth, i.e., the front-to-rear position of the upper rotating body 3 equipped to the hydraulic excavator 1, by using the second line image 67, and can grasp the widthwise position of the bucket 8 by using the first line image 66.

In the tool guide image 60, the cutting edge position image 61 is displayed along the surface WAP of the work object WA and the grid image 65. Therefore, the operator can grasp the positional relationship between the bucket 8 and the work object WA from the grid image 65 and the cutting edge position image 61, improving work efficiency and work accuracy. In the embodiment, the first straight line image 62 and the second straight line image 63 connect both ends of the cutting edge position image 61 from both sides of the width direction Wb of the bucket 8. The operator can more easily grasp the positional relationship between the bucket 8 and the work object WA from the first straight line image 62 and the second straight line image 63. Since the grid image 65 and the cutting edge position image 61 are displayed along the shape of the terrain (work object WA) to be worked on, the relative positional relationship between the two on the terrain surface (two-dimensionally) can be easily grasped. Furthermore, the first line image 66 and the second line image 67 constituting the grid image 65 are arranged at equal intervals in the global coordinate system, making it easy to grasp the sense of distance on the terrain surface and to grasp the sense of perspective.

In the embodiment, the work image 69 includes information 64 indicating the distance between the cutting edge 8T of the bucket 8 and the work object WA. This has the advantage that the operator can grasp the actual distance between the cutting edge 8T of the bucket 8 and the work object WA. The distance between the cutting edge 8T of the bucket 8 and the work object WA can be the distance from the cutting edge 8T at the center of the width direction Wb of the bucket 8 to the surface WAP of the work object WA.

In addition, the information 64 may be, instead of or in addition to the distance between the cutting edge 8T of the bucket 8 and the work object WA, any information related to the position of the work tool or the work object W, including information related to the posture, such as the angle of the bucket 8, information indicating the relative distance between the bucket 8 and the work object WA, information indicating the relationship between the orientation of, for example, the cutting edge 8T of the bucket 8 and the orientation of the surface of the work object WA, information indicating the position of the bucket 8 in coordinates, information indicating the orientation of the surface of the work object WA, and information indicating the distance in the x direction in the local coordinate system from the imaging device 19 to the cutting edge 8T of the bucket 8.

That is, the processing device 51 may determine at least one of the position of the bucket 8, which is a work tool, the attitude of the bucket 8, the position of the work object WA, the relative attitude of the work object WA, the relative distance between the bucket 8 and the work object WA, and the relative attitude between the bucket 8 and the work object WA, and display it on the display device 52.

As described above, the image display system 100 and the remote operation system 101 superimpose the work tool guide image 60 and the grid image 65 generated from the viewpoint of the imaging device 19 on the image 68 of the actual work object WA captured by the imaging device 19 and display them on the display device 52. Through such processing, the image display system 100 and the remote operation system 101 can make it easier for the operator who remotely operates the hydraulic excavator 1 to understand the positional relationship between the bucket 8 and the work object WA using the image of the work object WA displayed on the display device 52, thereby improving work efficiency and work accuracy. Even an inexperienced operator can easily understand the positional relationship between the bucket 8 and the work object WA by using the image display system 100 and the remote operation system 101. As a result, the decrease in work efficiency and work accuracy is suppressed. In addition, the image display system 100 and the remote operation system 101 superimpose the work tool guide image 60, the grid image 65, and the image 68 of the actual work object WA on the display device 52, thereby making it possible to improve work efficiency by making the screen that the operator focuses on during work a single screen.

In the lattice image 65, the spacing between adjacent first line images 66 is equal to the spacing between adjacent second line images 67. Therefore, by superimposing the lattice image 65 on an image 68 of the actual work object WA captured by the imaging device 19, the work point on the work object WA can be easily grasped. In addition, by superimposing the cutting edge position image 61 of the work tool guide image 60 on the lattice image 65, the operator can easily grasp the distance traveled by the bucket 8, improving work efficiency.

The tool guide image 60 and the grid image 65 are free of the occupied area SA, which is the area of the work machine 2, so that the tool guide image 60 and the grid image 65 can be prevented from being distorted by the occupied area SA and from being superimposed on the work machine 2. As a result, the image display system 100 and the remote control system 101 can display the work image 69 on the display device 52 in a form that is easy for the operator to see.

In the embodiment, the work implement guide image 60 may include at least the cutting edge position image 61. The grid image 65 may include at least a plurality of second line images 67, i.e., a plurality of line images indicating a direction perpendicular to the fore-aft direction of the upper rotating body 3 equipped on the hydraulic excavator 1. In addition, the processing device 51 may change the color of, for example, the cutting edge position image 61 in the work implement guide image 60 depending on the distance between the cutting edge 8T of the bucket 8 and the work object WA. In this way, it becomes easier for the operator to grasp the distance between the position of the bucket 8 and the work object WA.

In the embodiment, the processing device 51 converts the shape information of the work object WA into the global coordinate system (X, Y, Z) to generate the tool guide image 60 and the grid image 65, but the shape information of the work object WA does not have to be converted into the global coordinate system (X, Y, Z). In this case, the processing device 51 handles the shape information of the work object WA in the local coordinate system (x, y, z) of the hydraulic excavator 1 and generates the tool guide image 60 and the grid image 65. When the shape information of the work object WA is handled in the local coordinate system (x, y, z) of the hydraulic excavator 1, the GNSS antennas 21, 22 and the global position calculation device 23 are not required.

In the above embodiment, a part of the hydraulic excavator 1 detected by the distance detection device 20 (e.g., the bucket 8 as described above) is removed, and the shape information of the work object WA (three-dimensional terrain data) is obtained. However, three-dimensional terrain data acquired in the past (e.g., several seconds ago) may be stored in the memory unit 51M of the processing device 51, and the processing unit 51P of the processing device 51 may determine whether the current work object WA and the stored three-dimensional terrain data are in the same position, and if they are in the same position, the grid image 65 may be displayed using the past three-dimensional terrain data. In other words, even if there is terrain hidden by part of the hydraulic excavator 1 as viewed from the imaging device 19, the processing device 51 may be able to display the grid image 65 as long as there is past three-dimensional terrain data.

In addition, instead of displaying the grid image 65 using a grid, the grid image 65 may be displayed, for example, with the local coordinate system as a polar coordinate system. Specifically, concentric circles may be drawn as line images (second line images) at equal intervals according to the distance from the center of the hydraulic excavator 1 (for example, the rotation center of the upper rotating body 3), and radial line images (first line images) may be drawn at equal intervals from the rotation center according to the rotation angle of the upper rotating body 3. In this case, the second line image, which is a line image of concentric circles, intersects with the first line image, which is a line image of radial lines from the rotation center. By displaying such a grid image, the positional relationship between the bucket 8 and the work object WA during rotation or excavation can be easily grasped.

<Image 61 of cutting edge position of loading shovel type work machine 2a>
FIG. 17 is a diagram for explaining a cutting edge position image 61 in the case where a loading shovel type working machine 2a is used. In the loading shovel, the bucket 8 rotates from the rear to the front of the hydraulic excavator 1, so that it can scoop up soil and sand. In the loading shovel type working machine 2a, the cutting edge 8T of the bucket 8 faces the front of the upper rotating body 3, and excavates the work object WA, which is the work object in front of the upper rotating body 3. In this case, as shown in FIG. 17, the cutting edge position image 61 is an image defined by the position Pgt (X, Y, Z) of the surface WAP of the work object WA when the cutting edge 8T is projected on the work object WA in the horizontal direction, that is, in the direction perpendicular to the direction in which gravity acts. The horizontal direction is the X direction or Y direction in the global coordinate system (X, Y, Z), and is perpendicular to Z. The processing device 51 uses information on the position Pgt (X, Y, Z) of the surface WAP of the work object WA to generate a cutting edge position image 61, a first straight line image 62, and a second straight line image 63 using a method similar to the above-mentioned method. The processing device 51 converts the generated cutting edge position image 61, the first straight line image 62, and the second straight line image 63 into images from the viewpoint of the imaging device 19, and obtains a work tool guide image 60.

<Process for Obtaining Blade Tip Position Image 61>
Figure 18 is a diagram showing a first modified example of the process for obtaining a cutting edge position image. In the first modified example, the processing device 51 obtains a straight line 72 that is perpendicular to an intersection line 71 between an imaginary plane 70 and the work object WA and passes through the cutting edge 8T of the bucket 8. The imaginary plane 70 is the xz plane in the local coordinate system (x, y, z) of the hydraulic excavator 1 shown in Figures 5 and 6. The xz plane passes through the center of the bucket 8 in the width direction Wb.

Next, the processing device 51 determines a straight line LV1 that passes through an outer position Pgb1 of the blade 8B at one end 8Wt1 side of the width direction Wb of the bucket 8 and is parallel to the straight line 72, and a straight line LV2 that passes through an outer position Pgb2 of the blade 8B at the other end 8Wt2 side of the width direction Wb and is parallel to the straight line 72. The intersection of the straight line LV1 and the surface WAP of the work object WA is the first position Pgt1, and the intersection of the straight line LV2 and the surface WAP of the work object WA is the second position Pgt2. The processing device 51 determines the first position Pgt1 and the second position Pgt2, and the set of positions Pgt of the surface WAP when the straight line connecting the first position Pgt1 and the second position Pgt2 is projected onto the surface WAP of the work object WA is the cutting edge position image 61.

The first straight line image 62 and the second straight line image 63 are images of the straight lines LV1 and LV2. The processing device 51 converts the generated cutting edge position image 61, the first straight line image 62, and the second straight line image 63 into images from the viewpoint of the imaging device 19 to obtain the work tool guide image 60. Since the bucket 8 moves parallel to the virtual plane 70, the cutting edge position image 61 obtained by the processing of the first modified example indicates the position where the cutting edge 8T of the bucket 8 faces the work object WA.

Figures 19 and 20 are diagrams for explaining a second modified example of the process for obtaining a cutting edge position image. When the upper rotating body 3 of the hydraulic excavator 1 is tilted relative to the horizontal plane, i.e., the XY plane of the global coordinate system (X, Y, Z), as shown in Figure 19, the row of cutting edges 8T of the bucket 8 may be tilted relative to the surface WAP of the work object WA. Because the bucket 8 moves parallel to the virtual plane 70 described above, when the cutting edge 8T is projected onto the surface WAP of the work object WA that is in the vertical direction of the cutting edge 8T to obtain a cutting edge position image 61, there is a possibility that a misalignment will occur between the moving direction of the bucket 8 and the cutting edge position image 61.

In the second modified example, the processing device 51 obtains straight lines LV1 and LV2 extending vertically from the blade tip position P4 of the bucket 8. Next, the processing device 51 rotates the obtained straight lines LV1 and LV2 by the angle at which the upper rotating body 3 of the hydraulic excavator 1 is tilted with respect to the horizontal plane, that is, the roll angle θ4. The straight lines LV1 and LV2 are rotated in a direction in which they are parallel to the virtual plane 70. In this case, the processing device 51 rotates the straight lines LV1 and LV2 by θ4 on the plane PV12 formed by the straight lines LV1 and LV2, centered on the positions Pgb1 and Pgb2 of the bucket 8. In this way, the processing device 51 obtains the straight lines LV1a and LV2a after rotation.

Next, the processing device 51 obtains the intersections between the rotated straight lines LV1a and LV2a and the surface WAP of the work object WA, and sets the two intersections obtained as the first position Pgt1a and the second position Pgt2a, respectively. The processing device 51 then sets the set of positions Pgt of the surface WAP when a straight line connecting the first position Pgt1a and the second position Pgt2a is projected onto the surface WAP of the work object WA as the cutting edge position image 61. The first straight line image 62 and the second straight line image 63 are images of the straight lines LV1a and LV2a. The processing device 51 converts the generated cutting edge position image 61, the first straight line image 62, and the second straight line image 63 into images from the viewpoint of the imaging device 19 to obtain the work tool guide image 60. The cutting edge position image 61 obtained by the processing of the second modified example shows the position where the cutting edge 8T of the bucket 8 faces the work object WA.

<Modification of the control system of the hydraulic excavator 1>
Fig. 21 is a diagram showing a control system 1Sa of a hydraulic excavator 1 according to a modified example. The image display system 100 and remote operation system 101 described above remotely operate the hydraulic excavator 1 using the operation device 53 of the facility 50 shown in Fig. 1. In this modified example, a display device 52 is provided in the operator's cab 4 shown in Fig. 2, and a work image 69 is displayed on the display device 52 to assist the operator in performing work on the hydraulic excavator 1.

For this reason, in the control system 1Sa, the processing device 51 and the operation device 53a are connected to the signal line 35 of the control system 1S described above. The display device 52 is connected to the processing device 51. The processing device 51 provided in the control system 1Sa has the same functions as the processing device 51 provided in the facility 50 shown in FIG. 1 in the image display system 100 and the remote operation system 101 described above. The display device 52 of the control system 1Sa may be a dedicated display device for displaying the work image 69, or may be a display device provided in the hydraulic excavator 1. The operation device 53a is a device for operating the hydraulic excavator 1, and is provided with a left operation lever 53La and a right operation lever 53Ra. The operation device 53a may be a pilot hydraulic type or an electric type.

The hydraulic excavator 1 equipped with the control system 1Sa displays the work implement guide image 60 and the grid image 65 generated from the viewpoint of the imaging device 19 on the display device 52 in the cab 4 together with the image 68 of the actual work object WA captured by the imaging device 19. Through such processing, the hydraulic excavator 1 can make it easier for the operator operating the hydraulic excavator 1 to grasp the positional relationship between the bucket 8 and the work object WA using the image of the work object WA displayed on the display device 52. As a result, the work efficiency and the accuracy of the work can be improved. In addition, by using the hydraulic excavator 1 equipped with the control system 1Sa, even an inexperienced operator can easily grasp the positional relationship between the bucket 8 and the work object WA. As a result, the decrease in the work efficiency and the accuracy of the work is suppressed. Furthermore, in the case of night work, etc., even in a situation where it is difficult for the operator to visually see the actual work object WA, the operator can work while looking at the work implement guide image 60 and the grid image 65 displayed on the display device 52, so the decrease in the work efficiency is suppressed.

Although the embodiment has been described above, the embodiment is not limited to the above content. The above-mentioned components include those that a person skilled in the art can easily imagine, those that are substantially the same, and those that are within the scope of what is called equivalent. Furthermore, the above-mentioned components can be combined as appropriate. Furthermore, at least one of various omissions, substitutions, and modifications of the components can be made without departing from the gist of the embodiment. The work machine is not limited to the hydraulic excavator 1, and may be other work machines such as a wheel loader or a bulldozer.

1 Hydraulic excavator 1B Vehicle body 1S, 1Sa Control system 2, 2a Work machine 3 Upper rotating body 4 Driver's seat 6 Boom 7 Arm 8 Bucket 8B Blade 8T Blade tip 16 First stroke sensor 17 Second stroke sensor 18 Third stroke sensor 19 Imaging device 20 Distance detection device 21, 22 Antenna (GNSS antenna)
23 Global position calculation device 26 Sensor controller 27 Work machine control device 32 Attitude detection device 33 IMU
50 Facility 51 Processing device 52 Display device 53, 53a Operation device 60 Work tool guide image (image)
61: cutting edge position image 62: first straight line image 63: second straight line image 65: grid image 66: first line image 67: second line image 68: image 69: work image 100: image display system of work machine (image display system)
101 Remote control system for work machines (remote control system)

Claims (6)

an imaging device for capturing an image of a work target of a work machine including a rotating body that rotates around a rotation center and a work implement having a work tool;
a processing device that identifies an intersection point where a line extending vertically from both ends of the blade tip of the work tool intersects with a surface of the work object, generates a line image extending from the intersection point toward the blade tip of the work tool , synthesizes the line image with an image of the work object captured by the imaging device, and displays the synthesized image on a display device.
Image display system for work machines. The synthesized and displayed image includes an image in which a portion corresponding to the work tool is projected onto a work object.
2. The image display system for a work machine according to claim 1. The processing device changes a color of the projected image depending on a distance between the work tool and the work object.
3. The image display system for a work machine according to claim 2. The processing device displays spatial position information related to a work tool or a work target on the synthesized and displayed image.
The image display system for a work machine according to any one of claims 1 to 3. The processing device corrects the display of the image or the projected image corresponding to the intersection based on inclination information between the work tool and the surface of the work object.
The image display system for a work machine according to any one of claims 1 to 3. A step of acquiring an image of a work target of a work machine including a rotating body that rotates around a rotation center and a work implement having a work tool, by an imaging device;
Identifying points of intersection where lines extending vertically from both ends of the cutting edge of the work tool intersect with the surface of the work object, and generating line images extending from the points of intersection toward the cutting edge of the work tool ;
A step of synthesizing the line image and an image of the work object acquired by the imaging device;
and displaying the combined image on a display device.
A method for displaying an image of a work machine.

Images