JP7263287B2 - working machine - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a working machine equipped with a monitor capable of displaying information regarding the attitude of a bucket.

In a work machine equipped with a multi-joint type work device (front work device) represented by a hydraulic excavator, the work device is driven based on the operation of the operation lever by the operator, and the terrain to be constructed is shaped into a desired shape. be. As a technique for supporting such work, there is machine guidance (MG). The MG displays target plane data indicating the desired shape (target plane) of the work surface to be finally realized, and posture information of the bucket, which is the front member positioned at the tip of the working device, on the monitor in the operator's cab. This is a technology that realizes operational support for the operator. In the MG, the bucket attitude information displayed on the monitor includes, for example, an icon that schematically represents the shape of the bucket, the difference in the inclination angle between the bottom surface of the bucket and the target plane (that is, the angle difference between the bucket and the target plane), and the like. .

In Patent Document 1, an image of a target construction surface (target surface) is displayed on a screen, and a linear image generated by extracting a portion corresponding to the bottom surface when the bucket is viewed from the side is displayed together with the image of the target construction surface. An excavating machine display system for displaying is disclosed.

WO2015/030266

The technique described in Patent Literature 1 emphasizes and displays the bottom surface of the bucket with a straight line image, so that the operator can easily understand the positional relationship and angle between the bottom surface of the bucket and the construction target surface.

However, when the actual bucket is viewed from the side, the shape of the bottom surface is often complicated rather than straight. For example, the bottom surface near the claw and the bottom surface behind the claw often have different inclination angles. In addition, the surface on the bottom surface of the bucket that the operator wants to use as a reference when proceeding with the excavation work differs from operator to operator. Therefore, for example, if the surface predetermined by the manufacturer as the surface indicating the bottom surface of the bucket on the monitor differs from the surface intended by the operator, it may be difficult for the operator to accurately grasp the positional relationship between the bucket and the target surface. .

When displaying information about the attitude of the bucket (orientation information) on the monitor, in addition to displaying a linear image as in Patent Document 1, the bottom surface of the bucket is simply expressed in a shape different from the actual one (for example, linear). There are methods that display an image (icon) of a bucket that has been drawn, and methods that display the difference value of the inclination angle between a certain reference plane and a target plane on the bottom surface of the bucket. can occur.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a working machine capable of displaying on a monitor information about the attitude of the bottom surface of the bucket intended by the operator.

The present application includes a plurality of means for solving the above problems. To give one example, a working device in which a plurality of front members including buckets are connected, and a plurality of attitude sensors for detecting the attitudes of the plurality of front members. a storage device storing terrain data defining the shape of the terrain surface for work using the work device; and a reference line , which is a line displayed as the bottom surface of the bucket when the bucket is viewed from the side. a monitor on which the two-dimensional shape of the terrain surface is displayed; posture data of the plurality of front members detected by the plurality of posture sensors; and rotation center and toe of the bucket calculated from the posture data . and a controller that calculates the positional relationship between the reference line and the terrain surface on the monitor based on the position data of and the terrain data, and displays the calculated positional relationship on the monitor. , the reference line is a straight line having one end located at the toe position of the bucket when the bucket is viewed from the side on the monitor, and the center of rotation of the bucket and the toe of the bucket are aligned. A switch is stored in the controller as a straight line forming an angle φ with a connecting first straight line and is operated when setting the angle φ , and the controller changes the posture when the switch is operated. calculating the distance between the toe of the bucket and the terrain surface based on the data and the terrain data, and displaying on the monitor a second straight line having the same inclination angle as that of the portion of the terrain data used for computing the distance ; and the first straight line is stored as a new angle φ instead of the angle φ . A straight line forming the new angle φ with the first straight line is displayed on the monitor as a new reference line in place of the reference line .

According to the present invention, since the posture information of the bottom surface of the bucket intended by the operator can be displayed on the monitor, the operator can accurately grasp the positional relationship between the target surface and the bucket.

1 is a side view schematically showing the appearance of a hydraulic excavator that is an example of a working machine according to a first embodiment; FIG. 2 is a functional block diagram of the display system according to the first embodiment; FIG. FIG. 2 is a side view of the hydraulic excavator 100; 8 is an explanatory diagram of a process of displaying an image 85 of the bucket 35 on the display screen 81 of the monitor 69 using the actual posture of the bucket 35 and the reference line 72 set on the bucket 35. FIG. FIG. 10 is a view showing the shape measurement result by the shape measurement sensor 68 when the front work device 30 is in the vicinity of the current terrain; FIG. 7 is a diagram showing the shape measurement result by the shape measurement sensor 68 when there is no front working device 30 near the current terrain. 4 is a flowchart showing details of processing of a reference line setting unit 63 according to the first embodiment; FIG. 8 is a diagram showing a specific example in step S40 of FIG. 7; FIG. 8 is a diagram showing a specific example in step S50 of FIG. 7; FIG. 8 is a diagram showing a specific example in step S60 of FIG. 7; The functional block diagram of the display system which concerns on 2nd Embodiment. 9 is a flowchart showing details of processing of a reference line setting unit 63 according to the second embodiment;

<First embodiment>
A first embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a side view schematically showing the appearance of a hydraulic excavator, which is an example of a working machine according to the present embodiment. Although a hydraulic excavator having a bucket as an attachment located at the tip of the front working device will be described below, various attachments such as a grapple, a breaker, and a lifting magnet can be used in addition to the bucket.

In FIG. 1, a hydraulic excavator 100 includes a multi-joint type front working device (working device) 30 in which a plurality of front members (boom 31, arm 33, bucket 35) rotating in the vertical direction are connected in series, It has an upper revolving body 20 and a lower running body 10 that constitute a vehicle body. The upper revolving body 20 is provided so as to be able to revolve with respect to the lower traveling body 10 . The upper revolving body 20 is configured by arranging each member on a revolving frame 21 , and the revolving frame 21 constituting the upper revolving body 20 can revolve with respect to the lower traveling body 10 . The base end of the boom 31, which is the base end of the front working device 30, is attached to the front part of the upper revolving body 20 constituting the vehicle body so as to be capable of rotating in the vertical direction, and the base end of the arm 33 is the boom A bucket 35 is supported at the tip of the arm 33 so as to be vertically rotatable.

The lower traveling body 10 includes a pair of crawlers 11a (11b) respectively wound around a pair of left and right crawler frames 12a (12b), and traveling hydraulic motors 13a (13b) (not shown) for driving the crawlers 11a (11b), respectively. mechanism). As for each structure of the lower traveling body 10, only one of the pair of left and right structures is illustrated and denoted by reference numerals, and the other structure is shown only by parenthesized reference numerals in the figure and omitted from illustration. .

The boom 31, the arm 33, the bucket 35, and the lower traveling body 10 are driven by hydraulic actuators such as a boom cylinder 32, an arm cylinder 34, a bucket cylinder 36, and left and right traveling hydraulic motors 13a (13b), respectively. In addition, the upper rotating body 20 is similarly driven by a rotating hydraulic motor 23, which is a hydraulic actuator, through a speed reduction mechanism 24, and performs a rotating operation in either the left or right direction with respect to the lower traveling body 10. As shown in FIG.

On the revolving frame 21 constituting the upper revolving body 20, operation levers for operating objects including the front working device 30 (a plurality of front members 31, 32, 35), the upper revolving body 20 and the lower traveling body 10 are provided. A cab (operator's cab) 25 in which (operating device) is mounted is arranged, along with an engine 22 which is a prime mover, a boom cylinder 32, an arm cylinder 34, a bucket cylinder 36, a turning hydraulic motor 23, and left and right traveling hydraulic motors. A hydraulic circuit system 41 including a hydraulic pump that supplies hydraulic fluid to a plurality of hydraulic actuators such as 13a (13b) is mounted.

(IMU50 (attitude sensor))
The revolving frame 21 (vehicle main body) that constitutes the upper revolving body 20 and the plurality of front members (the boom 31, the arm 33, and the bucket 35) that constitute the front working device 30 store data on their attitudes (hereinafter referred to as "orientation IMUs (Inertial Measurement Units) 50a to 50d are attached as attitude sensors for detecting data). Although the IMU 50d is attached to the revolving frame 21 in this embodiment, it may be attached anywhere on the upper revolving body 20 (vehicle body). Also, the attitude sensor is not limited to the IMU. For example, an inclination sensor may be used as the attitude sensor to detect the attitude data of each member (vehicle body and front member). In the following description, the four IMUs 50a, 50b, 50c, and 50d may be collectively referred to as IMU 50. Unique identification information is assigned to each of the IMUs 50a to 50d, and each IMU 50 adds the identification information to the detection result of the posture data and outputs it to the vehicle network, whereby a plurality of data transmitted over the vehicle network are output. It is possible to identify which IMU 50 is the detection result of each posture data.

The IMU 50 is capable of measuring angular velocity and acceleration. For example, if the mounted members such as the front members 31, 33, and 35 on which the IMUs 50 are arranged and the upper rotating body 20 are stationary, the direction of gravitational acceleration in the IMU coordinate system set for each IMU 50 (that is, , vertically downward direction) and the mounting state of the IMU 50 (that is, the relative positional relationship between the IMU 50 and the mounted member), the orientation (orientation) of each mounted member can be detected as orientation data. . Note that FIG. 1 illustrates the case where the IMU 50c for acquiring the attitude data of the bucket 35 is arranged in the component (bucket link member) of the link mechanism that connects the bucket 35 to the tip of the arm 33. Since the attitude data of the bucket 35 is obtained indirectly based on the hydraulic excavator design data, etc., the IMU 50 c can be treated as being mounted on the bucket 35 .

(Shape measurement sensor 68)
The shape measurement sensor 68 is a sensor capable of measuring the shape of an object to be excavated in front of or around the excavator 100 . As the shape measurement sensor 68, for example, a LiDAR (Light Detection and Ranging or Laser Imaging Detection and Ranging) that is mounted on the upper part of the cab 25 as shown in FIG. 1 and can measure the shape of an object in front of the hydraulic excavator 100 can be used. . LiDAR can measure the distance to the object by irradiating the object with scanning laser light and observing the scattered light and the reflected light, thereby measuring the shape of the object. The LiDAR of this embodiment measures the two-dimensional shape of the current topography (see FIGS. 3 and 4) by scanning laser light in the vertical direction.

In addition to the LiDAR, the shape measurement sensor 68 may be a sensor (for example, a stereo camera or an ultrasonic distance sensor) that can two-dimensionally or three-dimensionally measure the shape of about 10 m in front of the hydraulic excavator 100. Any method is acceptable.

Inside the cab 25, there is a monitor 69 that displays positional relationship information (for example, relative position and angle difference between the two) between the bucket 35 and the terrain surface (current terrain and target surface), and a monitor 69 that calculates the positional relationship information. and a controller 60 that performs processing such as displaying the calculated positional relationship information on a monitor 69 .

FIG. 2 is a functional block diagram schematically showing the configuration of the display system according to this embodiment extracted from the control system of the hydraulic excavator 100. As shown in FIG.

The display system shown in FIG. 2 includes a controller 60, IMUs 50a to 50d, a switch 67, a shape measurement sensor 68, and a monitor 69. The IMUs 50a to 50d, the switch 67, the shape measurement sensor 68, A monitor 69 is connected to the controller 60 .

The IMUs 50a to 50d output the detection results (orientation data) to the controller 60 via an in-vehicle network such as CAN communication.

(switch 67)
The switch 67 is operated by an operator (user) on the hydraulic excavator 100 when setting a reference line 72 (see FIG. 4 etc.) set on the bottom side of the bucket 35 . is installed in An ON/OFF signal (electrical signal) indicating the ON/OFF state of the switch 67 is output to the controller 60 (reference line setting unit 63), and the controller 60 grasps the ON/OFF state of the switch 67 from the signal. The switch 67 may be a push-button physical switch, or may be a virtual switch that is displayed on the monitor 69 and can be operated by touch panel operation, for example.

(controller 60)
The controller 60 executes a program stored in a storage device (eg, hard disk drive or flash memory) in the controller 60 by means of a processing device (eg, CPU), thereby obtaining a dimension/angle information storage unit 61, an attitude calculation unit 62, a reference It functions as a line setting unit 63 , a shape measuring unit 64 , a display screen generating unit 65 and a target surface generating unit 66 .

(Dimension/angle information storage unit 61)
The dimension/angle information storage unit 61 is a storage area allocated to a storage device within the controller 60 to store dimension/angle information (vehicle body information) of the hydraulic excavator 100 .

FIG. 3 is a side view of the excavator 100. FIG. As shown in FIG. 3, the length of the boom 31, that is, the length from the boom pin P1 to the arm pin P2 is L1. Also, the length of the arm 33, that is, the length from the arm pin P2 to the bucket pin P3 is L2. Also, the length of the bucket 35, that is, the length from the bucket pin P3 to the tip of the bucket (toe of the bucket 35) P4 is L3. Numerical values of these lengths L1, L2, and L3 are stored in the dimension/angle information storage unit 61 in advance.

A point P0 in FIG. 3 is the origin of the vehicle body coordinate system (local coordinate system) set in the upper swing structure 20 (hydraulic excavator 100), and ground plane). The dimension/angle information storage unit 61 stores in advance the coordinates of the boom pin P1 in the vehicle body coordinate system.

(Posture calculation unit 62)
The attitude calculation unit 62 calculates the attitude of the hydraulic excavator 100 (for example, , the inclination of the vehicle body, and the positions and inclinations of the front members 31, 33, and 35 in a coordinate system preset in the excavator 100 (the vehicle body coordinate system).

The boom angle .theta.1, arm angle .theta.2, bucket angle .theta.3, and vehicle body tilt angle .theta.4 calculated using the four IMUs 50 will now be described with reference to FIG. In FIG. 3, the inclination of the upper revolving structure 20 with respect to a coordinate system (for example, a global coordinate system) set on the ground, that is, the vertical direction of the horizontal plane (the direction perpendicular to the horizontal plane) and the vertical direction of the vehicle body (the direction of the turning center axis of the revolving structure 20) ) is defined as the angle (pitch angle) θ4, which is defined as the vehicle body tilt angle θ4. The vehicle body tilt angle θ4 can be calculated from data detected by the IMU 50d. In addition to the pitch angle, the tilt angle of the upper revolving body 20 also includes the roll angle, but here the roll angle is assumed to be zero for the sake of simplicity of explanation.

Also, let θ1 be the angle formed by the line segment connecting the boom pin P1 and the arm pin P2 and the vertical direction of the vehicle body, and let this be the boom angle θ1. The boom angle θ1 can be calculated, for example, from data detected by the IMU 50d and the IMU 50a. The angle between the line segment connecting the arm pin P2 and the bucket pin P3 and the straight line formed by the boom pin P1 and the arm pin P2 is defined as θ2, which is defined as the arm angle θ2. The arm angle θ2 can be calculated from detection data of the IMU 50d, IMU 50a and IMU 50b, for example. The angle between the line segment connecting the bucket pin P3 and the bucket tip P4 and the straight line formed by the arm pin P2 and the bucket pin P3 is defined as θ3, and this is defined as the bucket angle θ3. Bucket angle θ3 can be calculated, for example, from detection data of IMU 50d, IMU 50a, IMU 50b, and IMU 50c.

As described above, the attitude calculation unit 62 calculates the coordinates of the bucket toe P4 (see FIG. 3) and the attitude of the bucket 35 in the vehicle body coordinate system with the boom angle θ1, the arm angle θ2, and the bucket angle θ3 calculated from the detection data of the IMU 50. , and lengths L1, L2, and L3 stored in advance.

(Target plane generator 66)
The target surface generation unit 66 generates a target surface 70 from design data that three-dimensionally defines the target shape of the object to be constructed. The design data is pre-stored in the storage device within the controller 60 . The target plane generation unit 66 defines a line of intersection between a plane passing through the centers of the three front members 31, 33, and 35 constituting the front work device 30 (operation plane of the front work device 30) and the design data as a target plane 70. In the present embodiment, the target plane 70 is arranged in the vehicle body coordinate system and used as target plane data.

(Display screen generator 65)
The display screen generation unit 65 generates attitude data of the IMU 50 (attitude sensor), data indicating the position of the reference line 72 set on the bucket 35 (for example, the positions of points P3 and P4 and a bucket bottom angle φ described later), Based on topographical data (for example, target surface data and current topographical data) that define the shape of the topographical surface (for example, target surface 70 and current topographical data) related to work using the front work device 30, the reference line 72 and the target surface are determined. 70 is calculated, and the calculated positional relation information is displayed on the monitor 69 .

The reference line 72 and positional relationship information will be described with reference to FIG. 4 shows an image (bucket icon) of the bucket 35 on the display screen 81 of the monitor 69 using the actual attitude of the bucket 35 (see FIG. 4(a)) and the reference line 72 set on the bucket 35. 85 is an explanatory diagram of the process of displaying 85. FIG.

(reference line)
FIG. 4(a) is a view of the bucket 35 extracted from FIG. 3 (however, the posture of the bucket 35 is different from that in FIG. 3). A reference line 72 is set.

The reference line 72 is set on a coordinate system (bucket coordinate system) set for the bucket 35 and rotates as the bucket 35 rotates due to expansion and contraction of the bucket cylinder 36 . The bucket coordinate system of this embodiment shown in FIG. 4(a) is a two-dimensional coordinate system with the bucket pin P3 as the origin, the straight line extending from P3 to P4 as the x-axis, and the straight line orthogonal to this as the z-axis. is.

The reference line 72 is obtained by rotating a straight line P3P4 of length L3 connecting the bucket pin P3 and the bucket tip (bucket toe) P4 counterclockwise (counterclockwise) in FIG. is a straight line. In other words, the reference line 72 is a straight line that passes through the bucket tip P4 and forms an angle φ with the straight line P3P4. The numerical value of the angle φ is stored in a storage device within the controller 60, and φ is sometimes referred to as the bucket bottom angle in this specification.

The reference line 72 can be set (changed) by the operator operating the switch 67, and the procedure will be described later.

(location information)
The positional relationship information displayed on the monitor 69 includes, for example, the positional relationship between the terrain surface (for example, the target plane 70 and the current terrain 90) and the reference line 72 regarding the work using the front working device 30, the terrain surface and the reference line. There are 72 angle differences (differences between the tilt angles of the two) ψ. In the example of FIG. 4B, the positional relationship between the target plane 70 and the reference line 72 is indicated by an icon 85, and the angle difference ψ between the target plane 70 and the reference line 72 is indicated by a numerical value.

(Positional relationship information 1 (bucket icon display))
In FIG. 4B, a bucket icon (bucket image) 85 that schematically shows the bucket 35 is used to display the positional relationship between the target plane 70 and the reference line 72 . In the bucket icon 85, the bottom surface of the bucket is simply represented by a straight line 86 passing through the toe 87 of the bucket.

When displaying the bucket icon 85 on the monitor screen 81, the display screen generation unit 65 acquires the positions of the bucket pin P3 and the bucket tip P4 in the vehicle body coordinate system calculated by the posture calculation unit 62, and further calculates the bucket bottom surface angle φ to get A bucket icon 85 stored in advance in the controller 60 is appropriately enlarged or reduced in accordance with the scale of the monitor screen 81, the bucket icon 85 is displayed so that the toe 87 of the bucket icon 85 is positioned at the point P4, and the bucket icon 85 is displayed. The bucket icon 85 is rotated about the point P4 so that the bottom surface 86 of the line forms an angle φ with the straight line P3P4. Note that when the actual bucket 35 is rotated, the bucket icon 85 on the screen 81 is also rotated around the coordinates of the bucket pin P3.

The display screen generator 65 also scales the target plane 70 generated by the target plane generator 66 appropriately according to the scale of the monitor screen 81, and displays the target plane 70 in the vehicle body coordinate system. .

As a result, the bucket 35 in the posture shown in FIG. 4(a) is displayed as a bucket icon 85 on the screen 81 of the monitor 69 as shown in FIG. 4(b). At this time, the bucket icon 85 is displayed on the screen 81 so that the reference line 72 set on the bucket 35 matches the bucket bottom surface 86 of the bucket icon 85 .

The scale of the monitor screen 81 may be changed according to the distance between the bucket 35 and the target plane 70 closest thereto, so that the bucket icon 85 and the target plane 70 are always displayed on the screen 81 .

(Positional relationship information 2 (angular difference))
The display screen generation unit 65 calculates the position of the reference line 72 in the vehicle body coordinate system based on the positions of the bucket pin P3 and the bucket tip P4 in the vehicle body coordinate system calculated by the posture calculation unit 62 and the bucket bottom surface angle φ. do. Next, the display screen generator 65 calculates the angle difference ψ based on the calculated position of the reference line 72 and the position of the target plane 70 generated on the vehicle body coordinate system by the target plane generator 66, and It is displayed on the angle difference display section 82 on the 81 . In the example of FIG. 4B, 22 degrees is calculated as the angle difference ψ and displayed on the angle difference display section 82 .

Next, while describing the shape measuring unit 64 and the reference line setting unit 63, the procedure for setting the reference line 72 will be touched upon.

(Shape measurement unit 64)
The shape measurement unit 64 stores data on the shape of the object measured by the shape measurement sensor 68 as current terrain data (topography data) in the storage device within the controller 60 . However, the shape measurement unit 64 determines whether or not the front work device 30 is included in the measurement range of the shape measurement sensor 68. When it is determined that the front work device 30 is included, the shape measurement sensor 68 Shape data obtained by excluding the shape of the front working device 30 from the measured shape of the object can be stored in the storage device in the controller 60 as current terrain data (topography data). The determination of whether or not the front work device 30 is included in the measurement range of the shape measurement sensor 68 is based on, for example, the attitude of the front work device 30 calculated from the attitude data of a plurality of IMUs 50 (the attitude of the bucket 35 in the example described later). ) and the laser beam scanning range (measurement range) of the shape measurement sensor 68, it is possible to determine whether or not the front working device 30 is positioned within the laser beam scanning range (measurement range).

Details of the processing by the shape measuring unit 64 will be described with reference to FIGS. 5 and 6. FIG. FIG. 5 shows the case where the front work device 30 is present near the current topography, and FIG. 6 shows the case where the front work device 30 is not present near the current topography.

A current topography 90 in FIG. 5 is formed by a flat ground 91 on which the hydraulic excavator 100 is grounded and a sloped surface (inclined surface) 92 in front of the excavator. For example, the scanning range of the laser beam is defined by the shape measuring sensor 68, which is the range sandwiched between the uppermost line and the lowermost line among the plurality of single-dot chain lines shown in FIG. 5(a). and the shape of the object can be measured within this range. In this paper, this range is sometimes referred to as the measurement range.

When the front work device 30 is in the posture shown in FIG. 5(a), the shape measurement sensor 68 recognizes the shapes of thick solid lines 91a, 92a, 92c, and 93 in FIG. 5(a). In this case, since the bucket 35 is positioned in front of the shape measurement sensor 68, a part 93 of the shape of the bucket 35 is also recognized. Although the bucket 35 is positioned in front of the shape measurement sensor 68, the boom 31 and the arm 33 are not positioned (the boom 31 and the arm 33 are positioned on the right side of the front of the shape measurement sensor 68). Therefore, the shapes of the boom 31 and arm 33 are not recognized.

The shape measurement unit 64 determines whether the bucket 35 is positioned within the measurement range of the shape measurement sensor 68 based on the attitude of the bucket 35 calculated by the attitude calculation unit 62 . When it is determined that the bucket 35 is positioned within the measurement range, the measurement results 93 of the bucket 35 (see dotted line in FIG. 5B) are excluded from the overall measurement results.

The shape 93 of the bucket 35 may be excluded from the overall shape measured by the shape measurement sensor 68, and the shape after the exclusion may be stored in the storage device within the controller 60 as the current terrain data. However, it is preferable to complement the shape of the portion where the measurement result of the shape measurement sensor 68 is missing by one due to the exclusion based on the shape of the portion from which the measurement result was obtained. Therefore, in the example of FIG. 5C, the shape measurement unit 64 complements the measurement result of the shape measurement sensor 68 with a straight line portion 94 connecting both ends of the missing portion (that is, the end of the thick solid line 92a and the end of the thick solid line 92c). It is carried out. The scene where the reference line 72 is reset as in the present embodiment is predicted to be immediately before the start of the finishing work after the current topography 90 has been brought closer to the shape of the target surface 70, and the bucket 35 is shown in FIG. As shown in (a), it is presumed that they are often located near the current topography 90 . In addition, since the current topography 90 is approaching the flat target surface 70 immediately before the finishing work, there is little problem even if it is supplemented with a straight line as described above. Therefore, the portion where the current topography 90 cannot be measured by the bucket 35 can be supplemented as described above, and the operation of the front work device 30 only for moving the bucket 35 out of the measurement range of the shape measurement sensor 68 is unnecessary. so that finishing work can be started immediately.

By the way, as shown in FIG. 6 , when the bucket 35 is outside the measurement range of the shape measurement sensor 68 , that is, when the position and orientation information of the bucket 35 calculated by the orientation calculation unit 62 , the bucket 35 is measured by the shape measurement sensor 68 . If it is determined to be out of range, the shape measuring unit 64 recognizes that the shape measured by the shape measuring sensor 68 (thick solid line in FIG. 6) is the current terrain 90, and stores the current terrain data in the storage device as it is. remember as

(Reference line setting unit 63)
The reference line setting part 63 is a straight line passing through the toe position P4 of the bucket 35 in the attitude of the bucket 35 when the switch 67 is pressed (when switched from the OFF state to the ON state). A straight line having the same slope angle as the terrain surface of the existing terrain 90 measured and stored in the controller 60 is set as the reference line 72 .

However, the reference line 72 is set based on the terrain surface of the current terrain 90 in this way only when the distance D between the toe P4 of the bucket 35 and the current terrain 90 is less than or equal to the predetermined distance threshold value d0, and the switch The angle difference Δα between the reference line 72 and the current terrain 90 when 67 is pressed may be limited to a predetermined angle threshold value δ0 or less. The distance between the toe P4 of the bucket 35 and the current landform 90 can be calculated based on the posture data of the plurality of IMUs 50 and the current landform data stored by the shape measurement unit 64 . Further, the angle difference Δα between the reference line 72 and the current topography 90 when the switch 67 is pressed is obtained from the attitude data of the plurality of IMUs 50, the position data of the reference line 72, and the current topography data stored by the shape measuring unit 64. can be calculated based on

Details of the processing of the reference line setting unit 63 will be described using a flowchart. FIG. 7 is a flow chart showing the details of the processing of the reference line setting section 63. As shown in FIG. The reference line setting unit 63 executes the flowchart of FIG. 7 at a predetermined control period (for example, 10 milliseconds).

First, in step S10, the reference line setting unit 63 (controller 60) takes in the shape of the current terrain 90 (shape of the terrain surface) stored by the shape measuring unit 64. FIG.

Subsequently, in step S20, the reference line setting section 63 (controller 60) determines whether or not the switch 67 has been pressed based on the ON/OFF signal input from the switch 67. FIG. If it is determined that the switch 67 has not been pressed, the process is terminated. On the other hand, if it is determined in step S20 that the switch has been pushed, the process proceeds to step S40.

In step S40, the reference line setting unit 63 (controller 60) sets the distance D between the position of the bucket tip (bucket toe) P4 calculated by the attitude calculation unit 62 and the current terrain 90 captured in step S10 to a predetermined distance. It is determined whether it is equal to or less than the threshold value d0. That is, it is determined whether or not the distance D when the switch 67 is pressed is equal to or less than the distance threshold value d0.

For example, as shown in FIG. 8, the distance D can be calculated as the length of a vertical line drawn from the bucket tip P4 toward the current landform 90. As shown in FIG. It is also possible to extend a straight line vertically downward from the bucket tip P4, find the intersection of the straight line and the current topography 90, and set the distance D as the distance between the intersection and the bucket tip P4.

For example, 5 cm can be selected as the distance threshold d0, but the user may change the distance threshold d0 within a certain range.

If it is determined in step S40 that the distance D between the bucket tip P4 and the current topography 90 exceeds the distance threshold d0 (not equal to or less than the distance threshold d0), the process ends. On the other hand, if it is determined that the distance D between the bucket tip P4 and the current terrain 90 is equal to or less than the distance threshold d0, the process proceeds to step S50.

In step S50, the reference line setting unit 63 (controller 60) sets the ground angle (inclination angle with respect to the horizontal plane) α1 of the reference line 72 in the bucket attitude calculated by the attitude calculation unit 62 when the switch 67 is pressed, and the shape It is determined whether or not the difference (angle difference) between the inclination angle α2 with respect to the horizontal plane of the current landform 90 stored by the measurement unit 64 and the angle threshold value δ0 is less than or equal to the predetermined angle threshold value δ0. As the inclination angle α2 of the current terrain 90, for example, the inclination angle at the point closest to the bucket tip P4 in the current terrain can be used. The angle threshold δ0 may vary depending on the shape and size of the bucket 35, but an angle of around 10 degrees can be selected, for example. Note that the angle threshold value δ0 may be changed by the user as long as the value is within a certain range.

FIG. 9 is a diagram showing a specific example in step S50. The reference line 72 is set as a straight line passing through the bucket tip P4. In step S50, the angle formed by the reference line 72 with the horizontal plane, that is, the angle α1 of the reference line 72 with respect to the ground, is compared with the angle α2 formed with the horizontal plane by the current landform 90 stored in the shape measuring section 64, and both angles α1 and α2 are compared. is equal to or less than the angle threshold value δ0.

If it is determined in step S50 that the angle difference exceeds the angle threshold value δ0, the process ends. On the other hand, if it is determined in step S50 that the angle difference is equal to or less than the angle threshold value δ0, the process proceeds to step S60.

In step S60, the reference line setting unit 63 (controller 60) newly establishes a straight line that passes through the bucket tip P4 in the attitude of the bucket 35 when the switch 67 is pressed and that has the same inclination angle as the current terrain. set as a reference line 72.

FIG. 10 is a diagram showing a specific example in step S60. The current topography 90a and the current topography 90b in the figure show the current topography with different inclination angles (gradients) measured by the shape measuring unit 64 at different times (it means that two current topography with different inclination angles are measured at the same time). not shown). For example, if the process proceeds to step S60 after the current topography 90a is acquired in step S10, the reference line setting unit 63 (controller 60) sets the reference line 72a having the same inclination angle as the current topography 90a . On the other hand, when the current landform 90b is acquired in step S10, the reference line setting unit 63 (controller 60) sets the reference line 72b having the same inclination angle as the current landform 90b .

Storing the position of the reference line 72 in the controller 60 can be done in terms of the bucket bottom angle φ. The bucket bottom angle is φa when the reference line 72a is set in FIG. 10, and the bucket bottom angle is φb when the reference line 72b is set.

Through the above processing, a straight line passing through the bucket tip P4 in the attitude of the bucket 35 at the timing when the switch 67 is pressed and having the same inclination angle as the current terrain is set as the new reference line 72 . As a result, the monitor 69 displays a bucket icon 85 in which the new reference line 72 is aligned with the bottom surface 86 of the bucket.

If the determination in step S40 or step S50 is negative even though the switch 67 is pressed in step S20, and the reference line 72 is not changed, a message to that effect is displayed on the monitor 69. You may Also, when the determination in step S50 is affirmative and the reference line 72 is changed, the effect may be displayed on the monitor 69. FIG.

(Situation and effect of resetting the reference line)
A typical scene assumed as a scene for resetting the reference line 72 in the present embodiment is a timing after the shape of the current topography 90 is approximated to the shape of the target surface 70 and before the start of the finishing work. It's timing. The current topography 90 immediately before the finishing work is slightly deviated from the target surface 70, but is generally flat and has a uniform inclination angle. When the operator resets the reference line 72 before starting the finishing work, the operator uses an operation lever (not shown) in the cab 25 so that the bottom surface of the bucket, which he uses as a reference, is substantially parallel to the current topography. to operate the front work device 30. At this time, it is not necessary that the bottom surface of the bucket and the current topography are actually parallel, and it is sufficient for the operator to make the bucket 35 take the attitude that the bottom surface of the bucket is parallel to the current topography. At this time, the operator may bring the portion of the bottom of the bucket that the operator himself/herself thinks to be the bottom of the bucket into contact with the current topography.

When the operator presses the switch 67 after recognizing that the bottom surface of the bucket and the current topography are parallel, the controller 60 acquires the shape of the current topography 90 measured by the shape measurement sensor 68, and calculates the distance between the toe of the bucket and the current topography. When D is equal to or less than the threshold d0 and the angle difference between the reference line 72 and the current terrain is equal to or less than the threshold δ0, a straight line passing through the bucket toe P4 in the attitude of the bucket 35 at that time and having the same inclination angle as the current terrain 90 , is set as a new reference line 72 . As a result, a bucket icon 85 whose bottom surface is the bucket bottom surface intended by the operator is displayed on the screen 81 of the monitor 69 . That is, since the positional relationship information (the positional relationship and angle difference ψ between the bucket 35 and the target surface 70) with respect to the bottom surface of the bucket intended by the operator is displayed on the monitor 69, the operator can positional relationship can be accurately grasped.

However, in the above embodiment, the processing of the reference line setting unit 63 includes steps S40 and S50. The condition for resetting the reference line 72 is that it is small (threshold δ0 or less). By adding such a condition, it is possible to prevent the reference line 72 from being erroneously set again, and to prevent the setting of the reference line 72 that greatly deviates from the actual current terrain. Note that these conditions can be omitted.

In the above embodiment, it is determined whether or not the bucket 35 is included in the measurement range of the shape measurement sensor 68. If it is determined that the bucket 35 is included, It was decided to complement the shape of Since this eliminates the need for an operation only to move the bucket 35 out of the measurement range of the shape measurement sensor 68, the work of resetting the reference line 72 can be started quickly, and the finishing work can be started after the reset work is completed. You will be able to start quickly. As described above, when the reference line 72 is reset, the current terrain 90 is often flat. has little effect on the setting accuracy of

It should be noted that the scene in which this embodiment can be used is not limited to just before the start of the finishing work mentioned above. For example, a plate member such as an iron plate may be placed on top of the current landform, and the reference line 72 may be reset with reference to the plate member. In this way, since it is not necessary to flatten the current topography, the reference line 72 can be reset even when the operator's skill is not high or when the finishing work is not just started.

In the above description, the shape measurement sensor 68 is mounted on the excavator 100 to acquire the current terrain data, but the current terrain data may be acquired from outside the excavator 100 . Specifically, the current topography data may be obtained by communication from a server storing the current topography, a total station equipped with the shape measurement sensor 68, or a drone. Another acquisition method is to calculate the movement trajectory of the toe P4 of the bucket 35 based on the detection data of the plurality of IMUs 50 and store the calculated movement trajectory in the storage device in the controller 60 as the current terrain data. According to this method, there is no need to prepare special hardware other than the hydraulic excavator, and the current terrain data can be acquired by the hydraulic excavator 100 alone.

If it is difficult to acquire the current terrain data, the reference line 72 can be reset based on the inclination angle of the target surface 70. FIG. Next, this method will be explained.

<Second embodiment>
A second embodiment of the present invention will be described with reference to FIG. FIG. 11 is a functional block diagram schematically showing the configuration of the display system according to the second embodiment extracted from the control system of the hydraulic excavator 100. As shown in FIG. In this embodiment, differences from the first embodiment will be mainly described, and in the drawings used in this embodiment, the same members as those in the first embodiment will be denoted by the same reference numerals, and description thereof will be omitted. The configuration is the same as the first embodiment except for the portion shown in FIG.

In this embodiment, the shape measurement sensor 68 and the shape measurement unit 64 in the controller 60 are omitted from the configuration of the first embodiment, and the reference line 72 is reset by the target surface generation unit 66 instead of the current terrain 90. It is characterized in that it utilizes the target surface 70 to be measured.

Details of the processing of the reference line setting unit 63 in the second embodiment will be described using a flowchart. FIG. 12 is a flow chart showing details of processing of the reference line setting unit 63 in the second embodiment. The reference line setting unit 63 executes the flowchart of FIG. 12 at a predetermined control period (for example, 10 milliseconds).

First, in step S11, the reference line setting unit 63 (controller 60) acquires the shape of the target surface 70 (the shape of the terrain surface) stored by the target surface generating unit 66. FIG.

Subsequently, in step S20, the reference line setting section 63 (controller 60) determines whether or not the switch 67 has been pressed based on the ON/OFF signal input from the switch 67. FIG. If it is determined that the switch 67 has not been pressed, the process is terminated. On the other hand, if it is determined in step S20 that the switch has been pressed, the process proceeds to step S41.

In step S41, the reference line setting unit 63 (controller 60) sets the distance Dt between the position of the bucket tip (bucket toe) P4 calculated by the posture calculation unit 62 and the target plane 70 acquired in step S11 to a predetermined distance. It is determined whether it is equal to or less than the threshold value dt0. That is, it is determined whether or not the distance D when the switch 67 is pressed is equal to or less than the distance threshold dt0. Note that the distance Dt can be calculated in the same manner as the distance D in the first embodiment. The distance threshold dt0 can also be set similarly to d0 in the first embodiment.

If it is determined in step S41 that the distance Dt between the bucket tip P4 and the target surface 70 exceeds the distance threshold dt0 (not equal to or less than the distance threshold dt0), the process ends. On the other hand, if it is determined that the distance Dt between the bucket tip P4 and the target surface 70 is equal to or less than the distance threshold dt0, the process proceeds to step S51.

In step S51, the reference line setting unit 63 (controller 60) sets the ground angle (inclination angle with respect to the horizontal plane) α1 of the reference line 72 in the bucket attitude calculated by the attitude calculation unit 62 when the switch 67 is pressed, and the target It is determined whether or not the difference (angle difference) between the target surface 70 generated by the surface generation unit 66 and the inclination angle α3 with respect to the horizontal plane is equal to or less than a predetermined angle threshold value δt0. As the tilt angle α3 of the target plane 70, for example, the tilt angle at the point closest to the bucket tip P4 on the target plane can be used. The angle threshold δt0 can be set similarly to δ0 in the first embodiment.

If it is determined in step S51 that the angle difference exceeds the angle threshold value δt0, the process ends. On the other hand, if it is determined in step S51 that the angle difference is equal to or less than the angle threshold δt0, the process proceeds to step S61.

In step S61, the reference line setting unit 63 (controller 60) selects a straight line that passes through the bucket tip P4 in the attitude of the bucket 35 when the switch 67 is pressed and that has the same inclination angle as the target plane 70. A new reference line 72 is set.

Through the above processing, a straight line passing through the bucket tip P4 in the attitude of the bucket 35 at the timing when the switch 67 is pressed and having the same inclination angle as the target plane 70 is set as a new reference line 72 . As a result, the monitor 69 displays a bucket icon 85 in which the new reference line 72 is aligned with the bottom surface 86 of the bucket.

In the present embodiment, it is assumed that the reference line 72 is reset at the timing before starting the finishing work, as in the first embodiment. The current topography 90 immediately before the finishing work roughly matches the target surface 70 although there is some deviation. Therefore, in the present embodiment, the operator's operation is to make the bottom surface of the bucket, which is his reference, substantially parallel to the current topography 90, as in the first embodiment, but the controller 60 performs the processing instead of the current topography 90. Using the target plane 70, a straight line passing through the bucket toe P4 in the attitude of the bucket 35 when the switch 67 is pressed and having the same inclination angle as the target plane 70 is set as a new reference line 72. As a result, even without using the shape measurement sensor 68, the positional relationship information (the positional relationship and the angle difference ψ between the bucket 35 and the target surface 70) with respect to the bottom surface of the bucket intended by the operator is displayed on the monitor 69. Since the operator can accurately grasp the positional relationship between the target surface 70 and the bucket 35, the cost can be kept lower than in the first embodiment.

It should be noted that the present invention is not limited to the above-described embodiments, and includes various modifications within a scope that does not depart from the spirit of the present invention. For example, the present invention is not limited to those having all the configurations described in the above embodiments, and includes those having some of the configurations omitted. Also, part of the configuration according to one embodiment can be added to or replaced with the configuration according to another embodiment.

In the above description, the case where the target surface 70 and the current topography 90 are set on the vehicle body coordinate system has been exemplified for the sake of simplicity of explanation. The target surface 70 and the current terrain 90 may be set in any coordinate system such as the set global coordinate system (geographical coordinate system). However, in this case, it is necessary to acquire the global coordinates of the hydraulic excavator 100 (upper revolving body 20 ), so it is necessary to mount the GNSS antenna and the receiver on the hydraulic excavator 100 .

In the above description, the target surface 70 is displayed on the monitor screen 81 as shown in FIG. 4, but the current terrain 90 may be displayed.

Further, each configuration related to the controller 60, the function and execution processing of each configuration, etc. are realized partially or entirely by hardware (for example, logic for executing each function is designed by an integrated circuit). can be Further, the configuration related to the controller 60 may be a program (software) that realizes each function related to the configuration of the controller 60 by being read and executed by an arithmetic processing device (for example, a CPU). Information related to the program can be stored, for example, in a semiconductor memory (flash memory, SSD, etc.), a magnetic storage device (hard disk drive, etc.), a recording medium (magnetic disk, optical disk, etc.), or the like.

In addition, in the description of each of the above embodiments, the control lines and information lines are understood to be necessary for the description of the embodiments. does not necessarily indicate In reality, it can be considered that almost all configurations are interconnected.

DESCRIPTION OF SYMBOLS 10... Lower traveling body 20... Upper revolving body 21... Revolving frame 25... Cab (cab) 30... Front working device (working device) 31... Boom 32... Boom cylinder 33... Arm 34... Arm cylinder 35 Bucket 36 Bucket cylinder 41 Hydraulic circuit system 60 Controller 61 Dimension/angle information storage unit 62 Attitude calculation unit 63 Reference line setting unit 64 Shape measurement unit 65 Display screen generator 66 Target surface generator 67 Switch 68 Shape measurement sensor 69 Monitor 70 Target surface 72 Reference line 81 Monitor screen 82 Angle difference display unit 85... Bucket image (bucket icon), 86... Bucket bottom in icon, 87... Bucket toe in icon, 90... Current topography, 100... Hydraulic excavator

Claims (8)

a working device connecting a plurality of front members including buckets;
a plurality of attitude sensors for detecting the attitudes of the plurality of front members;
a storage device storing topographical data defining a shape of a topographical surface related to work using the working device;
a monitor displaying a reference line, which is a line displayed as the bottom surface of the bucket when the bucket is viewed from the side , and a two-dimensional shape of the terrain surface;
Based on the posture data of the plurality of front members detected by the plurality of posture sensors, the position data of the rotation center and toe of the bucket calculated from the posture data , and the terrain data , A working machine comprising a controller that calculates the positional relationship between the reference line and the terrain surface in and displays the calculated positional relationship on the monitor,
The reference line is a straight line whose one end is located at the toe position of the bucket when the bucket is viewed from the side on the monitor, and which connects the center of rotation of the bucket and the toe of the bucket. is stored in the controller as a straight line forming an angle φ with the first straight line,
A switch operated when setting the angle φ is provided,
The controller is
calculating the distance between the toe of the bucket and the terrain surface based on the attitude data and the terrain data when the switch is operated;
storing, on the monitor, an angle between the first straight line and the second straight line having the same inclination angle as that of the portion of the terrain data used to calculate the distance , as a new angle φ in place of the angle φ;
On the monitor, a straight line having one end positioned at the toe position of the bucket when the bucket is viewed from the side and forming the new angle φ with the first straight line is used as a new reference line to replace the reference line. A working machine characterized by being displayed on the monitor. The work machine of claim 1,
the shape of the terrain surface defined by the terrain data is the shape of the existing terrain;
further comprising a shape measurement sensor capable of measuring the shape of an object around the working machine;
A working machine, wherein the controller stores shape data of the object measured by the shape measuring sensor as the terrain data in the storage device. The work machine of claim 2,
The controller is
determining whether or not the working device is included within the measurement range of the shape measuring sensor;
When it is determined that the working device is included in the measurement range, the shape data obtained by excluding the shape of the working device from the shape of the object measured by the shape measuring sensor is stored as the terrain data. A working machine characterized by memorizing in a device. The work machine of claim 3,
A working machine, wherein the controller determines whether or not the working device is included in the measuring range based on the attitude of the working device calculated from the attitude data and the measuring range. The work machine of claim 4,
When it is determined that the work device is included in the measurement range, the controller measures the shape data of the portion where the measurement result of the shape measurement sensor is missing due to the exclusion of the shape of the work device. A working machine characterized in that complementation is performed based on the shape of the portion from which the measurement result of the sensor is obtained. The work machine of claim 1,
the shape of the terrain surface defined by the terrain data is the shape of the existing terrain;
The working machine, wherein the controller calculates a movement trajectory of the toe of the bucket based on the attitude data, and stores the calculated movement trajectory in the storage device as the landform data. The work machine of claim 1,
A working machine, wherein the shape of the terrain surface defined by the terrain data is a shape of a target surface indicating a target shape of a construction target. The work machine of claim 1,
The controller further
calculating an angular difference between the reference line and the terrain surface when the switch is operated based on the attitude data, the position data of the reference line, and the terrain data;
storing the new angle φ instead of the angle φ when the distance is less than or equal to a predetermined distance threshold and the angle difference is less than or equal to the predetermined angle threshold;
causing the monitor to display the new reference line based on the stored new angle φ;
A working machine characterized by:

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