Excavator
The excavator's spatial recognition system allows for precise volume measurement of earth and sand in the bucket, addressing the volume measurement gap in existing technologies and improving loading accuracy.
Patent Information
- Application Number
- JP2020090944
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2020-05-25
- Publication Date
- 2024-12-19
- Estimated Expiration
- 2040-05-25
AI Technical Summary
Existing devices fail to measure the volume of sediment captured within the bucket of an excavator, limiting the recognition of earth and sand loaded on a dump truck.
An excavator equipped with a first and second spatial recognition device, a bucket, and a control device that calculates the volume of the object taken into the bucket based on the output of these devices, allowing for accurate measurement of the volume.
Enables the excavator to accurately determine the volume of earth and sand loaded into the bucket, enhancing operational efficiency and precision in loading operations.
Smart Images

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Abstract
Description
[Technical field]
[0001] The present disclosure relates to a shovel. [Background technology]
[0002] 2. Description of the Related Art There is known a device that accumulates and displays the weight of earth and sand that an excavator has loaded onto the bed of a dump truck (see Patent Document 1).
[0003] This device detects the start and completion of the loading operation based on whether or not a specific operation is being performed. Then, the device calculates the amount of soil and sand loaded onto the dump truck as an integrated value of a plurality of excavation weights calculated from the start to the completion of the loading operation on the dump truck. The soil discharge operation is an operation that includes a bucket opening operation. [Prior art documents] [Patent documents]
[0004] [Patent Document 1] International Publication No. 2019 / 031551 Summary of the Invention [Problem to be solved by the invention]
[0005] However, the above-mentioned device does not measure the volume of soil that has been taken into the bucket, and therefore cannot recognize the volume of soil that has been loaded onto the bed of the dump truck.
[0006] Therefore, it is desirable to provide a shovel that can obtain the volume of soil and other materials that have been taken into the bucket. [Means for solving the problem]
[0007] A shovel according to an embodiment of the present invention includes a lower traveling body, an upper rotating body rotatably mounted on the lower traveling body, an attachment attached to the upper rotating body, a bucket constituting the attachment, a first spatial recognition device attached to the attachment, a second spatial recognition device attached to the upper rotating body, and the bucket. When an object is taken into the bucket, the upper surface of the object taken into the bucket The output of the first spatial recognition device, which includes the above in a monitoring range; , no measurement is performed by the first spatial recognition device The bucket The exterior and a control device that calculates the shape of the object taken into the bucket based on the output of the second spatial recognition device, which includes the object within its monitoring range. Effect of the Invention
[0008] The above-mentioned shovel can obtain the volume of an object held in the bucket. [Brief description of the drawings]
[0009] [Figure 1] FIG. [Diagram 2] FIG. 1 is a diagram illustrating an example of a configuration of a shovel. [Diagram 3] FIG. 1 is a diagram illustrating an example of a configuration of a hydraulic system of a shovel. [Figure 4] FIG. 2 is a diagram illustrating an example of components related to an operation system in a hydraulic system of a shovel. [Diagram 5] FIG. 2 is a diagram illustrating an example of a configuration of a controller. [Figure 6] FIG. [Figure 7] FIG. 1 is a conceptual diagram of voxelization. [Figure 8] FIG. 1 is a side view of a shovel equipped with a plurality of shape estimation devices. [Figure 9] FIG. 13 is a diagram illustrating another example of the configuration of the controller. [Figure 10] FIG. 4 is a diagram showing an example of the configuration of a main screen. [Figure 11]FIG. 13 is a schematic diagram illustrating parameters related to calculation of soil weight. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0010] Hereinafter, an embodiment of the invention will be described with reference to the drawings.
[0011] [Outline of the excavator] First, an overview of a shovel 100 according to one embodiment of the present invention will be described with reference to Fig. 1. Fig. 1 is a side view of the shovel 100. In Fig. 1, the shovel 100 is located on a horizontal plane adjacent to an upward slope ES to be worked on, and an upward slope BS (i.e., the slope shape after work on the upward slope ES) which is an example of a target work surface to be described later is also shown. Note that a stake (not shown) is provided on the upward slope ES to be worked on, indicating the normal direction of the upward slope BS which is the target work surface.
[0012] The shovel 100 comprises a lower running body 1, an upper rotating body 3 mounted on the lower running body 1 so as to be freely rotatable via a rotating mechanism 2, a boom 4, an arm 5, and a bucket 6 that constitute an excavation attachment which is an example of an attachment (work machine), and a cabin 10.
[0013] The lower traveling body 1 has a pair of left and right crawlers that are hydraulically driven by traveling hydraulic motors 1L, 1R (see FIG. 2), respectively, to travel the excavator 100. That is, the pair of traveling hydraulic motors 1L, 1R (an example of a traveling motor) drive the lower traveling body 1 (crawlers) as a driven part.
[0014] The upper rotating body 3 is driven by a swing hydraulic motor 2A (see FIG. 2) to swing relative to the lower traveling body 1. In other words, the swing hydraulic motor 2A is a swing drive part that drives the upper rotating body 3 as a driven part, and can change the orientation of the upper rotating body 3.
[0015] The upper rotating body 3 may be electrically driven by an electric motor (hereinafter, "electric motor for rotation") instead of the hydraulic motor for rotation 2A. In other words, the electric motor for rotation is a rotation drive part that drives the upper rotating body 3 as a non-driven part, similar to the hydraulic motor for rotation 2A, and can change the orientation of the upper rotating body 3.
[0016] The boom 4 is pivotally attached to the front center of the upper rotating body 3 so as to be able to tilt up and down, an arm 5 is pivotally attached to the tip of the boom 4 so as to be able to rotate up and down, and a bucket 6 as an end attachment is pivotally attached to the tip of the arm 5 so as to be able to rotate up and down. The boom 4, arm 5, and bucket 6 are hydraulically driven by a boom cylinder 7, an arm cylinder 8, and a bucket cylinder 9, each of which serves as a hydraulic actuator.
[0017] Incidentally, the bucket 6 is an example of an end attachment, and other end attachments, such as a slope bucket, a dredging bucket, a breaker, etc., may be attached to the tip of the arm 5 instead of the bucket 6 depending on the work content, etc.
[0018] The cabin 10 is a cab in which an operator sits, and is mounted on the front left side of the upper rotating body 3.
[0019] [Excavator configuration] Next, a specific configuration of the shovel 100 will be described with reference to Fig. 2 in addition to Fig. 1. Fig. 2 is a diagram that shows a schematic example of the configuration of the shovel 100. In Fig. 2, a mechanical power system, a hydraulic oil line, a pilot line, and an electric control system are indicated by double lines, solid lines, dashed lines, and dotted lines, respectively.
[0020] The drive system of the excavator 100 includes the engine 11, a regulator 13, a main pump 14, and a control valve 17. In addition, the hydraulic drive system of the excavator 100 includes hydraulic actuators such as the traveling hydraulic motors 1L, 1R, the swing hydraulic motor 2A, the boom cylinder 7, the arm cylinder 8, and the bucket cylinder 9, which hydraulically drive the lower traveling structure 1, the upper rotating structure 3, the boom 4, the arm 5, and the bucket 6, respectively, as described above.
[0021] The engine 11 is a main power source in the hydraulic drive system, and is mounted, for example, on the rear of the upper rotating body 3. Specifically, the engine 11 rotates at a constant speed at a preset target speed under direct or indirect control by a controller 30 (described later), and drives the main pump 14 and the pilot pump 15. The engine 11 is, for example, a diesel engine that uses diesel as fuel.
[0022] The regulator 13 controls the discharge amount of the main pump 14. For example, the regulator 13 adjusts the angle (tilt angle) of the swash plate of the main pump 14 in response to a control command from the controller 30. The regulator 13 includes, for example, regulators 13L and 13R, as described below.
[0023] The main pump 14 is mounted on the rear of the upper rotating body 3, for example, like the engine 11, and supplies hydraulic oil to the control valve 17 through a high-pressure hydraulic line. The main pump 14 is driven by the engine 11 as described above. The main pump 14 is, for example, a variable displacement hydraulic pump, and as described above, under the control of the controller 30, the tilt angle of the swash plate is adjusted by the regulator 13 to adjust the stroke length of the piston, thereby controlling the discharge flow rate (discharge pressure). The main pump 14 includes, for example, main pumps 14L and 14R, as described below.
[0024] The control valve 17 is a hydraulic control device mounted, for example, at the center of the upper rotating body 3, and controls the hydraulic drive system in response to an operation of the operating device 26 by an operator. As described above, the control valve 17 is connected to the main pump 14 via a high-pressure hydraulic line, and selectively supplies hydraulic oil supplied from the main pump 14 to the hydraulic actuators (travel hydraulic motors 1L, 1R, swing hydraulic motor 2A, boom cylinder 7, arm cylinder 8, and bucket cylinder 9) in response to the operating state of the operating device 26. Specifically, the control valve 17 includes control valves 171 to 176 that control the flow rate and flow direction of hydraulic oil supplied from the main pump 14 to each of the hydraulic actuators. More specifically, the control valve 171 corresponds to the travel hydraulic motor 1L, the control valve 172 corresponds to the travel hydraulic motor 1R, and the control valve 173 corresponds to the swing hydraulic motor 2A. In addition, the control valve 174 corresponds to the bucket cylinder 9, the control valve 175 corresponds to the boom cylinder 7, and the control valve 176 corresponds to the arm cylinder 8. Further, the control valve 175 includes, for example, control valves 175L and 175R as described later, and the control valve 176 includes, for example, control valves 176L and 176R as described later. The control valves 171 to 176 will be described in detail later.
[0025] The operation system of the shovel 100 includes the pilot pump 15 and an operation device 26. The operation system of the shovel 100 also includes a shuttle valve 32 as a component related to a machine control function by a controller 30, which will be described later.
[0026] The pilot pump 15 is mounted, for example, on the rear of the upper rotating body 3 and supplies pilot pressure to the operating device 26 via a pilot line. The pilot pump 15 is, for example, a fixed displacement hydraulic pump, and is driven by the engine 11 as described above.
[0027] The operation device 26 is provided near the cockpit of the cabin 10, and is an operation input means for the operator to operate various operation elements (such as the lower traveling body 1, the upper rotating body 3, the boom 4, the arm 5, or the bucket 6). In other words, the operation device 26 is an operation input means for the operator to operate hydraulic actuators (i.e., the traveling hydraulic motors 1L and 1R, the swing hydraulic motor 2A, the boom cylinder 7, the arm cylinder 8, the bucket cylinder 9, or the like) that drive the respective operation elements. The operation devices 26 are connected to the control valves 17 directly through their secondary pilot lines, or indirectly through shuttle valves 32 (described later) provided in the secondary pilot lines. This allows pilot pressures corresponding to the operation states of the lower traveling body 1, the upper rotating body 3, the boom 4, the arm 5, and the bucket 6 in the operation device 26 to be input to the control valve 17. Therefore, the control valve 17 can drive the respective hydraulic actuators in accordance with the operation states in the operation device 26. The operation device 26 includes, for example, a lever device that operates the arm 5 (arm cylinder 8). The operation device 26 also includes, for example, lever devices 26A to 26C that operate the boom 4 (boom cylinder 7), bucket 6 (bucket cylinder 9), and upper rotating body 3 (swing hydraulic motor 2A) (see FIG. 4). The operation device 26 also includes, for example, lever devices and pedal devices that operate the pair of left and right crawlers (travel hydraulic motors 1L, 1R) of the lower traveling body 1.
[0028] The shuttle valve 32 has two inlet ports and one outlet port, and outputs hydraulic oil having a higher pilot pressure of the two pilot pressures input to the two inlet ports to the outlet port. One of the two inlet ports of the shuttle valve 32 is connected to the operating device 26, and the other is connected to the proportional valve 31. The outlet port of the shuttle valve 32 is connected to the pilot port of the corresponding control valve in the control valve 17 through a pilot line (see FIG. 4 for details). Therefore, the shuttle valve 32 can apply the higher of the pilot pressure generated by the operating device 26 and the pilot pressure generated by the proportional valve 31 to the pilot port of the corresponding control valve. In other words, the controller 30, which will be described later, can control the corresponding control valve and control the operation of various operating elements without depending on the operation of the operating device 26 by the operator by outputting a pilot pressure higher than the secondary pilot pressure output from the operating device 26 from the proportional valve 31. The shuttle valve 32 includes, for example, shuttle valves 32AL, 32AR, 32BL, 32BR, 32CL, and 32CR, as will be described later.
[0029] The operating device 26 (left operating lever, right operating lever, left travel lever, and right travel lever) may be an electric type that outputs an electric signal, instead of a hydraulic pilot type that outputs a pilot pressure. In this case, the electric signal from the operating device 26 is input to the controller 30, and the controller 30 controls each of the control valves 171 to 176 in the control valve 17 in response to the input electric signal, thereby realizing the operation of various hydraulic actuators in response to the operation content of the operating device 26. For example, the control valves 171 to 176 in the control valve 17 may be electromagnetic solenoid type spool valves that are driven by commands from the controller 30. Also, for example, solenoid valves that operate in response to electric signals from the controller 30 may be disposed between the pilot pump 15 and the pilot ports of each of the control valves 171 to 176. In this case, when manual operation is performed using the electric operating device 26, the controller 30 controls the solenoid valve and increases or decreases the pilot pressure using an electric signal corresponding to the amount of operation (e.g., the amount of lever operation), thereby operating each of the control valves 171 to 176 in accordance with the operation content of the operating device 26.
[0030] The control system of the excavator 100 includes a controller 30, a discharge pressure sensor 28, an operating pressure sensor 29, a proportional valve 31, a display device 40, an input device 42, an audio output device 43, a memory device 47, a boom angle sensor S1, an arm angle sensor S2, a bucket angle sensor S3, a machine body inclination sensor S4, a turning state sensor S5, an imaging device S6, a shape estimation device S10, a positioning device PS, and a communication device T1.
[0031] The controller 30 (an example of a control device) is provided, for example, in the cabin 10 and controls the driving of the excavator 100. The functions of the controller 30 may be realized by any hardware, software, or a combination thereof. For example, the controller 30 is mainly configured with a microcomputer including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), a non-volatile auxiliary storage device, various input / output interfaces, etc. The controller 30 realizes various functions by, for example, executing various programs stored in the ROM or the non-volatile auxiliary storage device on the CPU.
[0032] For example, the controller 30 sets a target rotation speed based on a work mode or the like that is set in advance by a predetermined operation by an operator or the like, and performs drive control to rotate the engine 11 at a constant speed.
[0033] Furthermore, for example, the controller 30 outputs a control command to the regulator 13 as necessary to change the discharge amount of the main pump 14.
[0034] Furthermore, for example, the controller 30 performs control related to a machine guidance function that guides (guides) the manual operation of the shovel 100 by an operator through the operation device 26. Furthermore, the controller 30 performs control related to a machine control function that automatically assists the manual operation of the shovel 100 by an operator through the operation device 26. That is, the controller 30 includes a machine guidance unit 50 as a functional unit related to the machine guidance function and the machine control function. Furthermore, the controller 30 includes a shape estimation unit 60, which will be described later.
[0035] Note that some of the functions of the controller 30 may be realized by another controller (control device). That is, the functions of the controller 30 may be realized in a distributed manner by a plurality of controllers. For example, the machine guidance function and the machine control function may be realized by a dedicated controller (control device).
[0036] The discharge pressure sensor 28 detects the discharge pressure of the main pump 14. A detection signal corresponding to the discharge pressure detected by the discharge pressure sensor 28 is input to the controller 30. The discharge pressure sensor 28 includes, for example, discharge pressure sensors 28L and 28R, as described later.
[0037] As described above, the operating pressure sensor 29 detects the secondary pilot pressure of the operating device 26, that is, the pilot pressure corresponding to the operating state (for example, the operating content such as the operating direction and the operating amount) of each operating element (i.e., the hydraulic actuator) in the operating device 26. A detection signal of the pilot pressure by the operating pressure sensor 29 corresponding to the operating states of the lower traveling body 1, the upper rotating body 3, the boom 4, the arm 5, the bucket 6, etc. in the operating device 26 is taken into the controller 30. The operating pressure sensor 29 includes, for example, operating pressure sensors 29A to 29C, as described later.
[0038] In addition, instead of the operating pressure sensor 29, other sensors capable of detecting the operating state of each operating element in the operating device 26, such as an encoder or potentiometer capable of detecting the operating amount (tilt amount) and tilt direction of the lever devices 26A to 26C, etc., may be provided.
[0039] The proportional valve 31 is provided in a pilot line connecting the pilot pump 15 and the shuttle valve 32, and is configured so that its flow path area (cross-sectional area through which hydraulic oil can flow) can be changed. The proportional valve 31 operates in response to a control command input from the controller 30. As a result, even if the operating device 26 (specifically, the lever devices 26A to 26C) is not operated by the operator, the controller 30 can supply the hydraulic oil discharged from the pilot pump 15 to the pilot port of the corresponding control valve in the control valve 17 via the proportional valve 31 and the shuttle valve 32. The proportional valve 31 includes, for example, proportional valves 31AL, 31AR, 31BL, 31BR, 31CL, and 31CR, as described later.
[0040] The display device 40 is provided in a location that is easily visible to an operator seated in the cabin 10, and displays various information images under the control of the controller 30. The display device 40 may be connected to the controller 30 via an in-vehicle communication network such as a Controller Area Network (CAN), or may be connected to the controller 30 via a one-to-one dedicated line.
[0041] The input device 42 is provided within reach of an operator seated in the cabin 10, accepts various operational inputs by the operator, and outputs signals corresponding to the operational inputs to the controller 30. The input device 42 includes a touch panel mounted on a display of a display device that displays various information images, knob switches provided at the tips of the lever portions of the lever devices 26A to 26C, button switches, levers, toggles, rotary dials, etc., provided around the display device 40. A signal corresponding to the content of an operation performed on the input device 42 is taken into the controller 30.
[0042] The audio output device 43 is provided, for example, in the cabin 10, connected to the controller 30, and outputs audio under the control of the controller 30. The audio output device 43 is, for example, a speaker or a buzzer. The audio output device 43 outputs various information by audio in response to an audio output command from the controller 30.
[0043] The storage device 47 is provided, for example, in the cabin 10, and stores various information under the control of the controller 30. The storage device 47 is, for example, a non-volatile storage medium such as a semiconductor memory. The storage device 47 may store information output by various devices during the operation of the shovel 100, or may store information acquired via various devices before the operation of the shovel 100 is started. The storage device 47 may store, for example, data related to a target construction surface acquired via the communication device T1 or the like, or set via the input device 42 or the like. The target construction surface may be set (saved) by the operator of the shovel 100, or may be set by a construction manager or the like.
[0044] The boom angle sensor S1 is attached to the boom 4 and detects the elevation angle of the boom 4 relative to the upper rotating body 3 (hereinafter referred to as the "boom angle"), for example, the angle formed by a straight line connecting the fulcrums at both ends of the boom 4 relative to the rotation plane of the upper rotating body 3 in a side view. The boom angle sensor S1 may include, for example, a rotary encoder, an acceleration sensor, a six-axis sensor, an IMU (Inertial Measurement Unit), etc. The boom angle sensor S1 may also include a potentiometer using a variable resistor, a cylinder sensor that detects the stroke amount of a hydraulic cylinder (boom cylinder 7) corresponding to the boom angle, etc. The same applies to the arm angle sensor S2 and bucket angle sensor S3 below. A detection signal corresponding to the boom angle by the boom angle sensor S1 is taken into the controller 30.
[0045] The arm angle sensor S2 is attached to the arm 5 and detects the rotation angle of the arm 5 relative to the boom 4 (hereinafter referred to as the “arm angle”), for example, the angle formed by a line connecting the fulcrums at both ends of the arm 5 with respect to a line connecting the fulcrums at both ends of the boom 4 in a side view. A detection signal corresponding to the arm angle by the arm angle sensor S2 is input to the controller 30.
[0046] The bucket angle sensor S3 is attached to the bucket 6 and detects the rotation angle of the bucket 6 with respect to the arm 5 (hereinafter referred to as the “bucket angle”), for example, the angle formed by a line connecting the fulcrum of the bucket 6 and the tip (blade tip) with respect to a line connecting the fulcrums of both ends of the arm 5 in a side view. A detection signal corresponding to the bucket angle by the bucket angle sensor S3 is input to the controller 30.
[0047] The machine body inclination sensor S4 detects the inclination state of the machine body (upper rotating body 3 or lower running body 1) with respect to a horizontal plane. The machine body inclination sensor S4 is attached to, for example, the upper rotating body 3, and detects the inclination angles around two axes in the forward / backward and left / right directions (hereinafter, "fore / aft inclination angle" and "left / right inclination angle") of the shovel 100 (i.e., upper rotating body 3). The machine body inclination sensor S4 may include, for example, a rotary encoder, an acceleration sensor, a six-axis sensor, an IMU, etc. A detection signal corresponding to the inclination angle (fore / aft inclination angle and left / right inclination angle) by the machine body inclination sensor S4 is input to the controller 30.
[0048] The turning state sensor S5 outputs detection information related to the turning state of the upper rotating body 3. The turning state sensor S5 detects, for example, the turning angular velocity and turning angle of the upper rotating body 3. The turning state sensor S5 may include, for example, a gyro sensor, a resolver, a rotary encoder, etc. A detection signal corresponding to the turning angle and turning angular velocity of the upper rotating body 3 detected by the turning state sensor S5 is input to the controller 30.
[0049] The imaging device S6 as a first spatial recognition device captures an image of the periphery of the shovel 100. The imaging device S6 is, for example, a monocular camera having an imaging element such as a CCD or a CMOS, and outputs the captured image to the display device 40. In this embodiment, the imaging device S6 includes a camera S6F that captures an image in front of the shovel 100, a camera S6L that captures an image to the left of the shovel 100, a camera S6R that captures an image to the right of the shovel 100, and a camera S6B that captures an image behind the shovel 100. The imaging device S6 may include an attachment camera attached to an attachment.
[0050] Camera S6F is attached, for example, to the ceiling of the cabin 10, i.e., inside the cabin 10. Camera S6F may also be attached to the outside of the cabin 10, such as to the roof of the cabin 10 or the side of the boom 4. Camera S6L is attached to the left end of the upper surface of the upper rotating body 3, camera S6R is attached to the right end of the upper surface of the upper rotating body 3, and camera S6B is attached to the rear end of the upper surface of the upper rotating body 3.
[0051] The imaging device S6 (cameras S6F, S6B, S6L, and S6R) is, for example, a monocular wide-angle camera having a wide angle of view. The imaging device S6 may also be a stereo camera or a distance imaging camera. Images captured by the imaging device S6 are input to the controller 30 via the display device 40. The imaging device S6 may also be directly connected to the controller 30 so as to be able to communicate with it.
[0052] The imaging device S6 as the first spatial recognition device may function as an object detection device. In this case, the imaging device S6 may detect an object present around the shovel 100. The detected object may include, for example, a person, an animal, a vehicle, a construction machine, a building, a hole, and the like. The imaging device S6 may also calculate the distance from the imaging device S6 or the shovel 100 to the recognized object and determine the type of the object. Therefore, the imaging device S6 as the object detection device may include, for example, a stereo camera, a distance image sensor, and the like.
[0053] The first spatial recognition device may be configured to calculate the distance from the first spatial recognition device or the shovel 100 to the recognized object. In addition to the imaging device S6, other object detection devices such as an RGB-D sensor, an ultrasonic sensor, a millimeter wave radar, a LIDAR, or an infrared sensor may be provided as the first spatial recognition device. When an RGB-D sensor, a LIDAR, a millimeter wave radar, an ultrasonic sensor, a laser radar, or the like is used as the first spatial recognition device, a number of signals (laser light, etc.) may be emitted toward the object and the reflected signals may be received to detect the distance and direction of the object from the reflected signals. When these object detection devices are provided, the imaging device S6 may be omitted.
[0054] The shape estimation device S10 as the second spatial recognition device is configured to estimate the shape of an object taken into the bucket 6. The shape estimation device S10 is configured to be configured, for example, with one or more LIDARs, and is configured to be able to transmit acquired information to the controller 30. However, the shape estimation device S10 may be configured with an RGB-D sensor, a stereo camera, a distance image sensor, a three-dimensional laser scanner, or the like. When an RGB-D sensor, LIDAR, millimeter wave radar, ultrasonic sensor, laser radar, or the like is used as the second spatial recognition device, a number of signals (laser light, etc.) may be emitted toward an object, and the reflected signals may be received to detect the distance and direction of the object from the reflected signals. In this embodiment, the shape estimation device S10 is configured with one LIDAR attached to the ventral surface of the arm 5. However, the shape estimation device S10 may be attached to other parts of the excavation attachment AT, such as the back or side of the arm 5, or the ventral surface, side, or back of the boom 4.
[0055] A boom rod pressure sensor S7R and a boom bottom pressure sensor S7B are attached to the boom cylinder 7. An arm rod pressure sensor S8R and an arm bottom pressure sensor S8B are attached to the arm cylinder 8. A bucket rod pressure sensor S9R and a bucket bottom pressure sensor S9B are attached to the bucket cylinder 9. The boom rod pressure sensor S7R, the boom bottom pressure sensor S7B, the arm rod pressure sensor S8R, the arm bottom pressure sensor S8B, the bucket rod pressure sensor S9R and the bucket bottom pressure sensor S9B are collectively referred to as "cylinder pressure sensors."
[0056] The boom rod pressure sensor S7R detects the pressure in the rod side oil chamber of the boom cylinder 7 (hereinafter referred to as the "boom rod pressure"), and the boom bottom pressure sensor S7B detects the pressure in the bottom side oil chamber of the boom cylinder 7 (hereinafter referred to as the "boom bottom pressure"). The arm rod pressure sensor S8R detects the pressure in the rod side oil chamber of the arm cylinder 8 (hereinafter referred to as the "arm rod pressure"), and the arm bottom pressure sensor S8B detects the pressure in the bottom side oil chamber of the arm cylinder 8 (hereinafter referred to as the "arm bottom pressure"). The bucket rod pressure sensor S9R detects the pressure in the rod side oil chamber of the bucket cylinder 9 (hereinafter referred to as the "bucket rod pressure"), and the bucket bottom pressure sensor S9B detects the pressure in the bottom side oil chamber of the bucket cylinder 9 (hereinafter referred to as the "bucket bottom pressure").
[0057] The positioning device PS measures the position and orientation of the upper rotating body 3. The positioning device PS is, for example, a Global Navigation Satellite System (GNSS) compass, and detects the position and orientation of the upper rotating body 3, and a detection signal corresponding to the position and orientation of the upper rotating body 3 is input to the controller 30. Furthermore, among the functions of the positioning device PS, the function of detecting the orientation of the upper rotating body 3 may be substituted by a direction sensor attached to the upper rotating body 3.
[0058] The communication device T1 communicates with external devices through a predetermined network including a mobile communication network with a base station as a terminal, a satellite communication network, the Internet, etc. The communication device T1 is, for example, a mobile communication module compatible with mobile communication standards such as LTE (Long Term Evolution), 4G (4th Generation), and 5G (5th Generation), or a satellite communication module for connecting to a satellite communication network.
[0059] The machine guidance unit 50 executes, for example, control of the shovel 100 related to the machine guidance function. The machine guidance unit 50 conveys, for example, work information such as the distance between the target construction surface and the tip of the attachment, specifically, the working part of the end attachment, to the operator through the display device 40, the audio output device 43, etc. Data related to the target construction surface is, for example, stored in advance in the storage device 47 as described above. Data related to the target construction surface is, for example, expressed in a reference coordinate system. The reference coordinate system is, for example, the World Geodetic System. The World Geodetic System is a three-dimensional orthogonal XYZ coordinate system with the origin at the center of gravity of the earth, the X axis in the direction of the intersection of the Greenwich meridian and the equator, the Y axis in the direction of 90 degrees east longitude, and the Z axis in the direction of the North Pole. The operator may determine an arbitrary point on the construction site as a reference point, and set the target construction surface through the input device 42 based on the relative positional relationship with the reference point. The working part of the bucket 6 is, for example, the tip of the bucket 6, the back surface of the bucket 6, etc. Furthermore, when, for example, a breaker is adopted as the end attachment instead of the bucket 6, the tip of the breaker corresponds to the working part. The machine guidance unit 50 notifies the operator of work information via the display device 40, the audio output device 43, etc., and guides the operator in operating the excavator 100 via the operating device 26.
[0060] Further, the machine guidance unit 50 executes control of the shovel 100 regarding, for example, a machine control function. The machine guidance unit 50 may automatically operate at least one of the boom 4, the arm 5, and the bucket 6 so that the tip position of the bucket 6 coincides with the target construction surface while, for example, an operator is manually performing an excavation operation.
[0061] The machine guidance unit 50 acquires information from the boom angle sensor S1, the arm angle sensor S2, the bucket angle sensor S3, the machine body inclination sensor S4, the turning state sensor S5, the imaging device S6, the positioning device PS, the communication device T1, the input device 42, and the like. Then, the machine guidance unit 50, for example, calculates the distance between the bucket 6 and the target construction surface based on the acquired information, notifies the operator of the degree of the distance between the bucket 6 and the target construction surface by the voice from the voice output device 43 and the image displayed on the display device 40, and automatically controls the operation of the attachment so that the tip of the attachment (specifically, the working part such as the tip or back of the bucket 6) coincides with the target construction surface. The machine guidance unit 50 includes a position calculation unit 51, a distance calculation unit 52, an information transmission unit 53, an automatic control unit 54, a turning angle calculation unit 55, and a relative angle calculation unit 56 as detailed functional configurations related to the machine guidance function and the machine control function.
[0062] The position calculation unit 51 calculates the position of a predetermined positioning target. For example, the position calculation unit 51 calculates the coordinate point in a reference coordinate system of a working part such as the tip of an attachment, specifically, the tip or back of the bucket 6. Specifically, the position calculation unit 51 calculates the coordinate point of the working part of the bucket 6 from the respective elevation and depression angles of the boom 4, arm 5, and bucket 6 (boom angle, arm angle, and bucket angle).
[0063] The distance calculation unit 52 calculates the distance between two positioning targets. For example, the distance calculation unit 52 calculates the distance between a working part such as the tip of the attachment, specifically, the tip or back of the bucket 6, and a target construction surface. The distance calculation unit 52 may also calculate the angle (relative angle) between the back of the bucket 6 as a working part and the target construction surface.
[0064] The information transmission unit 53 transmits (notifies) various pieces of information to the operator of the shovel 100 through a predetermined notification means such as the display device 40 or the audio output device 43. The information transmission unit 53 notifies the operator of the shovel 100 of the magnitude (degree) of various distances, etc. calculated by the distance calculation unit 52. For example, the information transmission unit 53 notifies the operator of the distance (the magnitude) between the tip of the bucket 6 and the target construction surface using at least one of the visual information from the display device 40 and the audio information from the audio output device 43. The information transmission unit 53 may also notify the operator of the relative angle (the magnitude) between the back surface of the bucket 6 as the working part and the target construction surface using at least one of the visual information from the display device 40 and the audio information from the audio output device 43.
[0065] Specifically, the information transmission unit 53 uses an intermittent sound from the audio output device 43 to inform the operator of the distance (e.g., vertical distance) between the working portion of the bucket 6 and the target construction surface. In this case, the information transmission unit 53 may shorten the interval of the intermittent sound as the vertical distance decreases, and may lengthen the interval of the intermittent sound as the vertical distance increases. The information transmission unit 53 may also use a continuous sound, or may express differences in the magnitude of the vertical distance by changing the pitch, strength, etc. of the sound. The information transmission unit 53 may also issue an alarm through the audio output device 43 when the tip of the bucket 6 is lower than the target construction surface, that is, when it has exceeded the target construction surface. The alarm is, for example, a continuous sound that is significantly louder than the intermittent sound.
[0066] Furthermore, the information transmission unit 53 may cause the display device 40 to display, as work information, the distance between the tip of the attachment, specifically the working portion of the bucket 6, and the target construction surface, the relative angle between the back surface of the bucket 6 and the target construction surface, etc. The display device 40 displays, under the control of the controller 30, the work information received from the information transmission unit 53 together with, for example, image data received from the imaging device S6. The information transmission unit 53 may convey the vertical distance to the operator using, for example, an image of an analog meter or an image of a bar graph indicator.
[0067] The automatic control unit 54 automatically assists the operator in manually operating the excavator 100 through the operation device 26 by automatically operating the actuators. Specifically, the automatic control unit 54 can individually and automatically adjust pilot pressures acting on control valves (specifically, the control valve 173, the control valves 175L, 175R, and the control valve 174) corresponding to a plurality of hydraulic actuators (specifically, the swing hydraulic motor 2A, the boom cylinder 7, and the bucket cylinder 9) as described later. This allows the automatic control unit 54 to automatically operate each hydraulic actuator. The control of the machine control function by the automatic control unit 54 may be executed, for example, when a predetermined switch included in the input device 42 is pressed. The predetermined switch may be, for example, a machine control switch (hereinafter, "MC (Machine Control) switch") and may be disposed as a knob switch at the tip of a portion of the operation device 26 (for example, a lever device corresponding to the operation of the arm 5) that is held by the operator. The following description will be given on the assumption that the machine control function is enabled when the MC switch is pressed.
[0068] For example, when an MC switch or the like is pressed, the automatic control unit 54 automatically extends and retracts at least one of the boom cylinder 7 and the bucket cylinder 9 in accordance with the operation of the arm cylinder 8 in order to support excavation work and shaping work. Specifically, when an operator manually performs a closing operation of the arm 5 (hereinafter, "arm closing operation"), the automatic control unit 54 automatically extends and retracts at least one of the boom cylinder 7 and the bucket cylinder 9 so that the target construction surface coincides with the position of a work part such as the tip or back surface of the bucket 6. In this case, the operator can close the arm 5 while aligning the tip, etc. of the bucket 6 with the target construction surface, simply by performing an arm closing operation on a lever device corresponding to the operation of the arm 5, for example.
[0069] Furthermore, when an MC switch or the like is pressed, the automatic control unit 54 may automatically rotate the swing hydraulic motor 2A (an example of an actuator) to make the upper swing body 3 face the target construction surface. Hereinafter, the control by the controller 30 (automatic control unit 54) to make the upper swing body 3 face the target construction surface is referred to as "facing control". As a result, an operator or the like can make the upper swing body 3 face the target construction surface simply by pressing a predetermined switch, or by operating a lever device 26C (described later) corresponding to a swing operation while the switch is pressed. Furthermore, an operator can make the upper swing body 3 face the target construction surface and start a machine control function related to the above-mentioned excavation work on the target construction surface, or the like, simply by pressing an MC switch.
[0070] For example, a state in which the upper rotating body 3 of the shovel 100 faces a target construction surface is a state in which the tip of the attachment (for example, the tip or back as a working part of the bucket 6) can be moved along the inclination direction of the target construction surface (upward slope BS) in accordance with the operation of the attachment. Specifically, a state in which the upper rotating body 3 of the shovel 100 faces a target construction surface is a state in which the working surface of the attachment (attachment working surface) perpendicular to the rotation plane of the shovel 100 includes the normal line of the target construction surface corresponding to the staking (in other words, a state along the normal line).
[0071] If the attachment operating surface of the shovel 100 does not include the normal line of the target construction surface corresponding to the stakeout, the tip of the attachment cannot move the target construction surface in the inclined direction. As a result, the shovel 100 cannot properly construct the target construction surface. In response to this, the automatic control unit 54 can orient the upper rotating body 3 by automatically rotating the swing hydraulic motor 2A. This allows the shovel 100 to properly construct the target construction surface.
[0072] In the facing control, the automatic control unit 54 determines that the shovel is facing the target construction surface, for example, when the left end vertical distance between the coordinate point of the left end of the tip of the bucket 6 and the target construction surface (hereinafter simply referred to as the "left end vertical distance") and the right end vertical distance between the coordinate point of the right end of the tip of the bucket 6 and the target construction surface (hereinafter simply referred to as the "right end vertical distance") become equal. Also, the automatic control unit 54 may determine that the shovel 100 is facing the target construction surface not when the left end vertical distance and the right end vertical distance become equal (i.e., when the difference between the left end vertical distance and the right end vertical distance becomes zero), but when the difference becomes equal to or less than a predetermined value.
[0073] In addition, the automatic control unit 54 may operate the swing hydraulic motor 2A in the facing control, for example, based on the difference between the left end vertical distance and the right end vertical distance. Specifically, when the lever device 26C corresponding to the swing operation is operated with a predetermined switch such as an MC switch pressed, the automatic control unit 54 judges whether the lever device 26C is operated in a direction to face the upper swing body 3 to the target construction surface. For example, when the lever device 26C is operated in a direction to increase the vertical distance between the tip of the bucket 6 and the target construction surface (upward slope BS), the automatic control unit 54 does not execute the facing control. On the other hand, when the swing operation lever is operated in a direction to decrease the vertical distance between the tip of the bucket 6 and the target construction surface (upward slope BS), the automatic control unit 54 executes the facing control. As a result, the automatic control unit 54 can operate the swing hydraulic motor 2A so that the difference between the left end vertical distance and the right end vertical distance becomes smaller. After that, when the difference becomes equal to or less than a predetermined value or becomes zero, the automatic control unit 54 stops the swing hydraulic motor 2A. The automatic control unit 54 may also set a swing angle at which the difference is equal to or less than a predetermined value or zero as a target angle, and control the operation of the swing hydraulic motor 2A so that the angle difference between the target angle and the current swing angle (specifically, the detection value based on the detection signal of the swing state sensor S5) becomes zero. In this case, the swing angle is, for example, the angle of the front-rear axis of the upper swing body 3 with respect to the reference direction.
[0074] As described above, when a swing electric motor is mounted on the excavator 100 instead of the swing hydraulic motor 2A, the automatic control unit 54 performs facing control with the swing electric motor (an example of an actuator) as the control target.
[0075] The slewing angle calculation unit 55 calculates the slewing angle of the upper rotating body 3. This allows the controller 30 to identify the current orientation of the upper rotating body 3. The slewing angle calculation unit 55 calculates the angle of the front-rear axis of the upper rotating body 3 with respect to a reference direction as the slewing angle based on, for example, an output signal of a GNSS compass included in the positioning device PS. The slewing angle calculation unit 55 may also calculate the slewing angle based on a detection signal of the turning state sensor S5. In addition, when a reference point is set at the construction site, the slewing angle calculation unit 55 may set the direction of the reference point as viewed from the turning axis as the reference direction.
[0076] The rotation angle indicates the direction in which the attachment working surface extends relative to the reference direction. The attachment working surface is, for example, a virtual plane that cuts the attachment longitudinally and is positioned so as to be perpendicular to the rotation plane. The rotation plane is, for example, a virtual plane that includes the bottom surface of the rotating frame that is perpendicular to the rotation axis. The controller 30 (machine guidance unit 50) determines that the upper rotating body 3 is directly facing the target construction surface when it determines, for example, that the attachment working surface includes the normal to the target construction surface.
[0077] The relative angle calculation unit 56 calculates a rotation angle (relative angle) required to make the upper rotating body 3 face the target construction surface. The relative angle is, for example, a relative angle formed between the direction of the front-rear axis of the upper rotating body 3 when the upper rotating body 3 is faced directly with the target construction surface and the current direction of the front-rear axis of the upper rotating body 3. The relative angle calculation unit 56 calculates the relative angle based on, for example, data related to the target construction surface stored in the storage device 47 and the rotation angle calculated by the rotation angle calculation unit 55.
[0078] When the lever device 26C corresponding to the rotation operation is operated with a predetermined switch such as an MC switch being pressed, the automatic control unit 54 judges whether the upper rotating body 3 has been rotated in a direction to face the target construction surface. When the automatic control unit 54 judges that the upper rotating body 3 has been rotated in a direction to face the target construction surface, the automatic control unit 54 sets the relative angle calculated by the relative angle calculation unit 56 as the target angle. When the change in the rotation angle after the lever device 26C is operated reaches the target angle, the automatic control unit 54 may judge that the upper rotating body 3 faces the target construction surface and stop the movement of the rotation hydraulic motor 2A. As a result, the automatic control unit 54 can make the upper rotating body 3 face the target construction surface on the premise of the configuration shown in FIG. 2. Although the above embodiment of the facing control has shown an example of the facing control to the target construction surface, the present invention is not limited to this. For example, even in the scooping operation when loading temporary soil and sand into a dump truck, a target excavation trajectory corresponding to the target volume may be generated, and the turning operation may be controlled so that the attachment faces the target excavation trajectory. In this case, the target excavation trajectory is changed every time a scooping operation is performed. Therefore, after the soil is discharged into the dump truck, the attachment is controlled to face the newly changed target excavation trajectory.
[0079] In addition, the swing hydraulic motor 2A has a first port 2A1 and a second port 2A2. The hydraulic sensor 21 detects the pressure of the hydraulic oil at the first port 2A1 of the swing hydraulic motor 2A. The hydraulic sensor 22 detects the pressure of the hydraulic oil at the second port 2A2 of the swing hydraulic motor 2A. Detection signals corresponding to the discharge pressures detected by the hydraulic sensors 21 and 22 are input to the controller 30.
[0080] In addition, the first port 2A1 is connected to a hydraulic oil tank via a relief valve 23. The relief valve 23 opens when the pressure on the first port 2A1 side reaches a predetermined relief pressure, and discharges the hydraulic oil on the first port 2A1 side to the hydraulic oil tank. Similarly, the second port 2A2 is connected to a hydraulic oil tank via a relief valve 24. The relief valve 24 opens when the pressure on the second port 2A2 side reaches a predetermined relief pressure, and discharges the hydraulic oil on the second port 2A2 side to the hydraulic oil tank.
[0081] [Excavator hydraulic system] Next, a hydraulic system of the shovel 100 will be described with reference to Fig. 3. Fig. 3 is a diagram showing an example of the configuration of the hydraulic system of the shovel 100.
[0082] In FIG. 3, the mechanical power system, hydraulic oil lines, pilot lines, and electrical control system are indicated by double lines, solid lines, dashed lines, and dotted lines, respectively, as in FIG. 2 and other figures.
[0083] The hydraulic system realized by the hydraulic circuit circulates hydraulic oil from each of the main pumps 14L, 14R driven by the engine 11 through center bypass oil passages C1L, C1R and parallel oil passages C2L, C2R to a hydraulic oil tank.
[0084] The center bypass oil passage C1L starts from the main pump 14L, passes through the control valves 171, 173, 175L, and 176L arranged in the control valve 17 in this order, and reaches the hydraulic oil tank.
[0085] The center bypass oil passage C1R starts at the main pump 14R, passes through the control valves 172, 174, 175R, and 176R arranged in the control valve 17 in this order, and reaches the hydraulic oil tank.
[0086] The control valve 171 is a spool valve that supplies the hydraulic oil discharged from the main pump 14L to the traveling hydraulic motor 1L, and discharges the hydraulic oil discharged from the traveling hydraulic motor 1L to a hydraulic oil tank.
[0087] The control valve 172 is a spool valve that supplies the hydraulic oil discharged from the main pump 14R to the traveling hydraulic motor 1R, and discharges the hydraulic oil discharged from the traveling hydraulic motor 1R to a hydraulic oil tank.
[0088] The control valve 173 is a spool valve that supplies the hydraulic oil discharged from the main pump 14L to the swing hydraulic motor 2A and discharges the hydraulic oil discharged from the swing hydraulic motor 2A to a hydraulic oil tank.
[0089] The control valve 174 is a spool valve that supplies the hydraulic oil discharged from the main pump 14R to the bucket cylinder 9 and also discharges the hydraulic oil in the bucket cylinder 9 to a hydraulic oil tank.
[0090] The control valves 175L and 175R are spool valves that supply the hydraulic oil discharged from the main pumps 14L and 14R to the boom cylinder 7 and discharge the hydraulic oil in the boom cylinder 7 to a hydraulic oil tank.
[0091] The control valves 176L, 176R supply the hydraulic oil discharged by the main pumps 14L, 14R to the arm cylinder 8, and discharge the hydraulic oil in the arm cylinder 8 to a hydraulic oil tank.
[0092] The control valves 171, 172, 173, 174, 175L, 175R, 176L, and 176R adjust the flow rate of hydraulic oil supplied to or discharged from the hydraulic actuator and switch the flow direction according to the pilot pressure acting on the pilot port.
[0093] The parallel oil passage C2L supplies hydraulic oil of the main pump 14L to the control valves 171, 173, 175L, and 176L in parallel with the center bypass oil passage C1L. Specifically, the parallel oil passage C2L branches off from the center bypass oil passage C1L on the upstream side of the control valve 171, and is configured to be able to supply hydraulic oil of the main pump 14L in parallel to each of the control valves 171, 173, 175L, and 176R. This allows the parallel oil passage C2L to supply hydraulic oil to a more downstream control valve when the flow of hydraulic oil through the center bypass oil passage C1L is restricted or blocked by any of the control valves 171, 173, and 175L.
[0094] The parallel oil passage C2R supplies hydraulic oil of the main pump 14R to the control valves 172, 174, 175R, and 176R in parallel with the center bypass oil passage C1R. Specifically, the parallel oil passage C2R branches off from the center bypass oil passage C1R on the upstream side of the control valve 172, and is configured to be able to supply hydraulic oil of the main pump 14R in parallel to each of the control valves 172, 174, 175R, and 176R. When the flow of hydraulic oil through the center bypass oil passage C1R is restricted or blocked by any of the control valves 172, 174, and 175R, the parallel oil passage C2R can supply hydraulic oil to a more downstream control valve.
[0095] Under the control of the controller 30, the regulators 13L and 13R adjust the tilt angles of the swash plates of the main pumps 14L and 14R, thereby adjusting the discharge amounts of the main pumps 14L and 14R.
[0096] The discharge pressure sensor 28L detects the discharge pressure of the main pump 14L, and a detection signal corresponding to the detected discharge pressure is input to the controller 30. The same is true for the discharge pressure sensor 28R. This allows the controller 30 to control the regulators 13L, 13R in accordance with the discharge pressures of the main pumps 14L, 14R.
[0097] The center bypass oil passages C1L, C1R are provided with throttles 18L, 18R between the hydraulic oil tank and the most downstream control valves 176L, 176R, respectively. As a result, the flow of hydraulic oil discharged by the main pumps 14L, 14R is restricted by the throttles 18L, 18R. The throttles 18L, 18R generate control pressures for controlling the regulators 13L, 13R.
[0098] The control pressure sensors 19L, 19R detect the control pressures, and the controller 30 receives detection signals corresponding to the detected control pressures.
[0099] The controller 30 may control the regulators 13L, 13R in response to the discharge pressure of the main pumps 14L, 14R detected by the discharge pressure sensors 28L, 28R to adjust the discharge volume of the main pumps 14L, 14R. For example, the controller 30 may control the regulator 13L in response to an increase in the discharge pressure of the main pump 14L to adjust the swash plate tilt angle of the main pump 14L to reduce the discharge volume. The same applies to the regulator 13R. This allows the controller 30 to perform total horsepower control of the main pumps 14L, 14R so that the absorption horsepower of the main pumps 14L, 14R, which is expressed by the product of the discharge pressure and the discharge volume, does not exceed the output horsepower of the engine 11.
[0100] Furthermore, the controller 30 may adjust the discharge rates of the main pumps 14L, 14R by controlling the regulators 13L, 13R in accordance with the control pressures detected by the control pressure sensors 19L, 19R. For example, the controller 30 decreases the discharge rates of the main pumps 14L, 14R as the control pressure increases, and increases the discharge rates of the main pumps 14L, 14R as the control pressure decreases.
[0101] Specifically, in the case of a standby state (state shown in FIG. 3) in which none of the hydraulic actuators in the excavator 100 are operated, the hydraulic oil discharged from the main pumps 14L, 14R passes through the center bypass oil passages C1L, C1R and reaches the throttles 18L, 18R. Then, the flow of the hydraulic oil discharged from the main pumps 14L, 14R increases the control pressure generated upstream of the throttles 18L, 18R. As a result, the controller 30 reduces the discharge amount of the main pumps 14L, 14R to the allowable minimum discharge amount, suppressing the pressure loss (pumping loss) that occurs when the discharged hydraulic oil passes through the center bypass oil passages C1L, C1R.
[0102] On the other hand, when any of the hydraulic actuators is operated through the operating device 26, the hydraulic oil discharged from the main pumps 14L, 14R flows into the hydraulic actuator to be operated through the control valve corresponding to the hydraulic actuator to be operated. The flow of hydraulic oil discharged from the main pumps 14L, 14R reduces or eliminates the amount of hydraulic oil reaching the throttles 18L, 18R, lowering the control pressure generated upstream of the throttles 18L, 18R. As a result, the controller 30 increases the discharge amount of the main pumps 14L, 14R, circulates sufficient hydraulic oil to the hydraulic actuator to be operated, and can reliably drive the hydraulic actuator to be operated.
[0103] [Configuration details for excavator machine control functions] Next, with reference to FIG. 4, a detailed configuration regarding the machine control function of the shovel 100 will be described.
[0104] Fig. 4 is a diagram that shows an example of a configuration part related to an operation system in the hydraulic system of the excavator 100. Specifically, Fig. 4(A) shows an example of a pilot circuit that applies pilot pressure to control valves 175L, 175R that hydraulically control the boom cylinder 7. Fig. 4(B) shows an example of a pilot circuit that applies pilot pressure to a control valve 174 that hydraulically controls the bucket cylinder 9. Fig. 4(C) shows an example of a pilot circuit that applies pilot pressure to a control valve 173 that hydraulically controls the swing hydraulic motor 2A.
[0105] 4(A), for example, lever device 26A is used by an operator or the like to operate boom cylinder 7 corresponding to boom 4. Lever device 26A utilizes hydraulic oil discharged from pilot pump 15 to output pilot pressure to the secondary side according to the operation content.
[0106] The shuttle valve 32AL has two inlet ports connected to the secondary pilot line of the lever device 26A corresponding to the operation of the boom 4 in the lifting direction (hereinafter referred to as the "boom lifting operation") and the secondary pilot line of the proportional valve 31AL, and an outlet port connected to the right pilot port of the control valve 175L and the left pilot port of the control valve 175R.
[0107] The shuttle valve 32AR has two inlet ports connected to the secondary pilot line of the lever device 26A corresponding to the operation of the boom 4 in the lowering direction (hereinafter referred to as the "boom lowering operation") and the secondary pilot line of the proportional valve 31AR, and an outlet port connected to the right pilot port of the control valve 175R.
[0108] That is, the lever device 26A applies a pilot pressure corresponding to the operation content (e.g., the operation direction and the operation amount) to the pilot ports of the control valves 175L and 175R via the shuttle valves 32AL and 32AR. Specifically, when the boom is raised, the lever device 26A outputs a pilot pressure corresponding to the operation amount to one inlet port of the shuttle valve 32AL, and applies the pilot pressure to the right pilot port of the control valve 175L and the left pilot port of the control valve 175R via the shuttle valve 32AL. Also, when the boom is lowered, the lever device 26A outputs a pilot pressure corresponding to the operation amount to one inlet port of the shuttle valve 32AR, and applies the pilot pressure to the right pilot port of the control valve 175R via the shuttle valve 32AR.
[0109] The proportional valve 31AL operates in response to a control current input from the controller 30. Specifically, the proportional valve 31AL uses the hydraulic oil discharged from the pilot pump 15 to output a pilot pressure corresponding to the control current input from the controller 30 to the other inlet port of the shuttle valve 32AL. This allows the proportional valve 31AL to adjust the pilot pressure acting on the right pilot port of the control valve 175L and the left pilot port of the control valve 175R via the shuttle valve 32AL.
[0110] The proportional valve 31AR operates in response to a control current input from the controller 30. Specifically, the proportional valve 31AR uses the hydraulic oil discharged from the pilot pump 15 to output a pilot pressure corresponding to the control current input from the controller 30 to the other inlet port of the shuttle valve 32AR. This allows the proportional valve 31AR to adjust the pilot pressure acting on the right pilot port of the control valve 175R via the shuttle valve 32AR.
[0111] In other words, the proportional valves 31AL, 31AR can adjust the pilot pressure output to the secondary side so that the control valves 175L, 175R can be stopped at any valve position, regardless of the operating state of the lever device 26A.
[0112] The proportional valve 33AL functions as a control valve for machine control, similar to the proportional valve 31AL. The proportional valve 33AL is disposed in a pipe connecting the operating device 26 and the shuttle valve 32AL, and is configured to be able to change the flow passage area of the pipe. In this embodiment, the proportional valve 33AL operates in response to a control command output by the controller 30. Therefore, the controller 30 can reduce the pressure of the hydraulic oil discharged by the operating device 26 and supply it to the pilot port of the corresponding control valve in the control valve 17 via the shuttle valve 32AL, regardless of the operation of the operating device 26 by the operator.
[0113] Similarly, the proportional valve 33AR functions as a control valve for machine control. The proportional valve 33AR is disposed in a pipe connecting the operating device 26 and the shuttle valve 32AR, and is configured to be able to change the flow passage area of the pipe. In this embodiment, the proportional valve 33AR operates in response to a control command output by the controller 30. Therefore, the controller 30 can reduce the pressure of the hydraulic oil discharged by the operating device 26 and supply it to the pilot port of the corresponding control valve in the control valve 17 via the shuttle valve 32AR, regardless of the operation of the operating device 26 by the operator.
[0114] The operation pressure sensor 29A detects the operation of the lever device 26A by the operator in the form of pressure (operation pressure), and a detection signal corresponding to the detected pressure is input to the controller 30. This allows the controller 30 to grasp the operation of the lever device 26A.
[0115] The controller 30 can supply the hydraulic oil discharged from the pilot pump 15 to the right pilot port of the control valve 175L and the left pilot port of the control valve 175R via the proportional valve 31AL and the shuttle valve 32AL, regardless of the boom-up operation of the lever device 26A by the operator. Furthermore, the controller 30 can supply the hydraulic oil discharged from the pilot pump 15 to the right pilot port of the control valve 175R via the proportional valve 31AR and the shuttle valve 32AR, regardless of the boom-down operation of the lever device 26A by the operator. That is, the controller 30 can automatically control the raising and lowering operation of the boom 4. Furthermore, the controller 30 can forcibly stop the operation of the hydraulic actuator corresponding to a specific operating device 26, even if the specific operating device 26 is being operated.
[0116] The proportional valve 33AL operates in response to a control command (current command) output by the controller 30. Then, it reduces the pilot pressure by the hydraulic oil introduced from the pilot pump 15 to the right pilot port of the control valve 175L and the left pilot port of the control valve 175R via the lever device 26A, the proportional valve 33AL, and the shuttle valve 32AL. The proportional valve 33AR operates in response to a control command (current command) output by the controller 30. Then, it reduces the pilot pressure by the hydraulic oil introduced from the pilot pump 15 to the right pilot port of the control valve 175R via the lever device 26A, the proportional valve 33AR, and the shuttle valve 32AR. The proportional valves 33AL and 33AR are capable of adjusting the pilot pressure so that the control valves 175L and 175R can be stopped at any valve position.
[0117] With this configuration, even when the operator is performing a boom-raising operation, the controller 30 can, as necessary, reduce the pilot pressure acting on the raising side pilot ports of the control valve 175 (the left pilot port of the control valve 175L and the right pilot port of the control valve 175R) to forcibly stop the closing operation of the boom 4. The same applies to the case where the lowering operation of the boom 4 is forcibly stopped when the operator is performing a boom-lowering operation.
[0118] Alternatively, even when the operator is performing a boom-raising operation, the controller 30 may control the proportional valve 31AR as necessary to increase the pilot pressure acting on the lowering pilot port of the control valve 175 (the right pilot port of the control valve 175R) opposite the raising pilot port of the control valve 175, and forcibly return the control valve 175 to the neutral position, thereby forcibly stopping the raising operation of the boom 4. In this case, the proportional valve 33AL may be omitted. The same applies to the case where the lowering operation of the boom 4 is forcibly stopped when the operator is performing a boom-lowering operation. In other words, the proportional valves 33AL and 33AR may be omitted.
[0119] As shown in Fig. 4(B), the lever device 26B is used by an operator or the like to operate the bucket cylinder 9 corresponding to the bucket 6. The lever device 26B uses the hydraulic oil discharged from the pilot pump 15 to output a pilot pressure to the secondary side according to the operation content.
[0120] The shuttle valve 32BL has two inlet ports connected to the secondary pilot line of the lever device 26B corresponding to the operation in the closing direction of the bucket 6 (hereinafter referred to as the "bucket closing operation") and the secondary pilot line of the proportional valve 31BL, and an outlet port connected to the left pilot port of the control valve 174.
[0121] The shuttle valve 32BR has two inlet ports connected to the secondary pilot line of the lever device 26B corresponding to the operation of the opening direction of the bucket 6 (hereinafter referred to as the "bucket opening operation") and the secondary pilot line of the proportional valve 31BR, and an outlet port connected to the right pilot port of the control valve 174.
[0122] That is, lever device 26B applies a pilot pressure corresponding to the operation content to the pilot port of control valve 174 via shuttle valves 32BL, 32BR. Specifically, when a bucket closing operation is performed, lever device 26B outputs a pilot pressure corresponding to the operation amount to one inlet port of shuttle valve 32BL, and applies the pilot pressure to the left pilot port of control valve 174 via shuttle valve 32BL. In addition, when a bucket opening operation is performed, lever device 26B outputs a pilot pressure corresponding to the operation amount to one inlet port of shuttle valve 32BR, and applies the pilot pressure to the right pilot port of control valve 174 via shuttle valve 32BR.
[0123] The proportional valve 31BL operates in response to a control current input from the controller 30. Specifically, the proportional valve 31BL uses the hydraulic oil discharged from the pilot pump 15 to output a pilot pressure corresponding to the control current input from the controller 30 to the other pilot port of the shuttle valve 32BL. In this way, the proportional valve 31BL can adjust the pilot pressure acting on the left pilot port of the control valve 174 via the shuttle valve 32BL.
[0124] The proportional valve 31BR operates in response to a control current output by the controller 30. Specifically, the proportional valve 31BR uses the hydraulic oil discharged from the pilot pump 15 to output a pilot pressure corresponding to the control current input from the controller 30 to the other pilot port of the shuttle valve 32BR. This allows the proportional valve 31BR to adjust the pilot pressure acting on the right pilot port of the control valve 174 via the shuttle valve 32BR.
[0125] In other words, the proportional valves 31BL, 31BR can adjust the pilot pressure output to the secondary side so that the control valve 174 can be stopped at any valve position, regardless of the operation state of the lever device 26B.
[0126] The proportional valve 33BL functions as a control valve for machine control, similar to the proportional valve 31BL. The proportional valve 33BL is disposed in a pipe connecting the operating device 26 and the shuttle valve 32BL, and is configured to be able to change the flow passage area of the pipe. In this embodiment, the proportional valve 33BL operates in response to a control command output by the controller 30. Therefore, the controller 30 can reduce the pressure of the hydraulic oil discharged by the operating device 26 and supply it to the pilot port of the corresponding control valve in the control valve 17 via the shuttle valve 32BL, regardless of the operation of the operating device 26 by the operator.
[0127] Similarly, the proportional valve 33BR functions as a control valve for machine control. The proportional valve 33BR is disposed in a pipe connecting the operating device 26 and the shuttle valve 32BR, and is configured to be able to change the flow passage area of the pipe. In this embodiment, the proportional valve 33BR operates in response to a control command output by the controller 30. Therefore, the controller 30 can reduce the pressure of the hydraulic oil discharged by the operating device 26 and supply it to the pilot port of the corresponding control valve in the control valve 17 via the shuttle valve 32BR, regardless of the operation of the operating device 26 by the operator.
[0128] The operation pressure sensor 29B detects the operation of the lever device 26B by the operator in the form of pressure (operation pressure), and a detection signal corresponding to the detected pressure is input to the controller 30. This allows the controller 30 to grasp the operation of the lever device 26B.
[0129] The controller 30 can supply the hydraulic oil discharged from the pilot pump 15 to the left pilot port of the control valve 174 via the proportional valve 31BL and the shuttle valve 32BL, regardless of the bucket closing operation of the lever device 26B by the operator. Furthermore, the controller 30 can supply the hydraulic oil discharged from the pilot pump 15 to the right pilot port of the control valve 174 via the proportional valve 31BR and the shuttle valve 32BR, regardless of the bucket opening operation of the lever device 26B by the operator. In other words, the controller 30 can automatically control the opening and closing operation of the bucket 6. Furthermore, the controller 30 can forcibly stop the operation of the hydraulic actuator corresponding to a specific operating device 26, even when the specific operating device 26 is being operated.
[0130] Incidentally, the operation of the proportional valves 33BL, 33BR that forcibly stop the movement of the bucket 6 when the operator is performing a bucket closing operation or a bucket opening operation is similar to the operation of the proportional valves 33AL, 33AR that forcibly stop the movement of the boom 4 when the operator is performing a boom raising operation or a boom lowering operation, and therefore a duplicated explanation will be omitted. Also, the proportional valves 33BL, 33BR may be omitted, similar to the proportional valves 33AL, 33AR.
[0131] 4(C), the lever device 26C is used by an operator or the like to operate the swing hydraulic motor 2A corresponding to the upper swing body 3 (swing mechanism 2). The lever device 26C uses the hydraulic oil discharged from the pilot pump 15 to output a pilot pressure to the secondary side according to the operation content.
[0132] The shuttle valve 32CL has two inlet ports connected to the secondary pilot line of the lever device 26C corresponding to the leftward rotation operation of the upper rotating body 3 (hereinafter referred to as "left rotation operation") and the secondary pilot line of the proportional valve 31CL, and an outlet port connected to the left pilot port of the control valve 173.
[0133] The shuttle valve 32CR has two inlet ports connected to the secondary pilot line of the lever device 26C corresponding to the rightward rotation operation of the upper rotating body 3 (hereinafter referred to as "right rotation operation") and the secondary pilot line of the proportional valve 31CR, and an outlet port connected to the right pilot port of the control valve 173.
[0134] That is, lever device 26C applies a pilot pressure corresponding to the operation in the left or right direction to a pilot port of control valve 173 via shuttle valves 32CL, 32CR. Specifically, when lever device 26C is operated to turn left, it outputs a pilot pressure corresponding to the operation amount to one inlet port of shuttle valve 32CL, and applies the pilot pressure to the left pilot port of control valve 173 via shuttle valve 32CL. Also, when lever device 26C is operated to turn right, it outputs a pilot pressure corresponding to the operation amount to one inlet port of shuttle valve 32CR, and applies the pilot pressure to the right pilot port of control valve 173 via shuttle valve 32CR.
[0135] The proportional valve 31CL operates in response to a control current input from the controller 30. Specifically, the proportional valve 31CL uses the hydraulic oil discharged from the pilot pump 15 to output a pilot pressure corresponding to the control current input from the controller 30 to the other pilot port of the shuttle valve 32CL. This allows the proportional valve 31CL to adjust the pilot pressure acting on the left pilot port of the control valve 173 via the shuttle valve 32CL.
[0136] The proportional valve 31CR operates in response to a control current output by the controller 30. Specifically, the proportional valve 31CR uses the hydraulic oil discharged from the pilot pump 15 to output a pilot pressure corresponding to the control current input from the controller 30 to the other pilot port of the shuttle valve 32CR. This allows the proportional valve 31CR to adjust the pilot pressure acting on the right pilot port of the control valve 173 via the shuttle valve 32CR.
[0137] In other words, the proportional valves 31CL, 31CR can adjust the pilot pressure to be output to the secondary side so that the control valve 173 can be stopped at any valve position, regardless of the operation state of the lever device 26C.
[0138] The proportional valve 33CL functions as a control valve for machine control, similar to the proportional valve 31CL. The proportional valve 33CL is disposed in a pipe connecting the operating device 26 and the shuttle valve 32CL, and is configured to be able to change the flow passage area of the pipe. In this embodiment, the proportional valve 33CL operates in response to a control command output by the controller 30. Therefore, the controller 30 can reduce the pressure of the hydraulic oil discharged by the operating device 26 and supply it to the pilot port of the corresponding control valve in the control valve 17 via the shuttle valve 32CL, regardless of the operation of the operating device 26 by the operator.
[0139] Similarly, the proportional valve 33CR functions as a control valve for machine control. The proportional valve 33CR is disposed in a pipe connecting the operating device 26 and the shuttle valve 32CR, and is configured to be able to change the flow passage area of the pipe. In this embodiment, the proportional valve 33CR operates in response to a control command output by the controller 30. Therefore, the controller 30 can reduce the pressure of the hydraulic oil discharged by the operating device 26 and supply it to the pilot port of the corresponding control valve in the control valve 17 via the shuttle valve 32CR, regardless of the operation of the operating device 26 by the operator.
[0140] The operation pressure sensor 29C detects the operation state of the lever device 26C by the operator as pressure, and a detection signal corresponding to the detected pressure is input to the controller 30. This allows the controller 30 to grasp the operation content of the lever device 26C in the left and right directions.
[0141] The controller 30 can supply the hydraulic oil discharged from the pilot pump 15 to the left pilot port of the control valve 173 via the proportional valve 31CL and the shuttle valve 32CL, regardless of the left rotation operation of the lever device 26C by the operator. In addition, the controller 30 can supply the hydraulic oil discharged from the pilot pump 15 to the right pilot port of the control valve 173 via the proportional valve 31CR and the shuttle valve 32CR, regardless of the right rotation operation of the lever device 26C by the operator. That is, the controller 30 can automatically control the left-right rotation operation of the upper rotating body 3. In addition, the controller 30 can forcibly stop the operation of the hydraulic actuator corresponding to a specific operating device 26, even if the specific operating device 26 is being operated.
[0142] Incidentally, the operation of the proportional valves 33CL, 33CR that forcibly stop the movement of the upper rotating body 3 when the operator is performing a swing operation is similar to the operation of the proportional valves 33AL, 33AR that forcibly stop the movement of the boom 4 when the operator is performing a boom-raising or boom-lowering operation, and therefore a duplicated explanation will be omitted. Also, the proportional valves 33CL, 33CR may be omitted, similar to the proportional valves 33AL, 33AR.
[0143] The excavator 100 may further include a configuration for automatically opening and closing the arm 5, and a configuration for automatically moving the lower traveling structure 1 forward and backward. In this case, in the hydraulic system, components related to the operation system of the arm cylinder 8, components related to the operation system of the traveling hydraulic motor 1L, and components related to the operation of the traveling hydraulic motor 1R may be configured similarly to the components related to the operation system of the boom cylinder 7, etc. (FIGS. 4(A) to 4(C)).
[0144] [Configuration details for excavator shape estimation function] Next, an example of the configuration related to the shape estimation function of the shovel 100 will be described with reference to Fig. 5 and Fig. 6. Fig. 5 is a diagram showing an example of the configuration related to the shape estimation function. Fig. 6 is a side view of the arm 5 and the bucket 6 when the shape estimation function is executed.
[0145] The shape estimation function is a function for estimating the shape of an object. In this embodiment, the shape estimation function is configured to estimate the shape of the earth and sand taken into the bucket 6.
[0146] 3, the controller 30 includes, as a functional unit related to the shape estimation function, the shape estimation unit 60. The shape estimation unit 60 has a bucket state estimation unit 61, a soil shape estimation unit 62, and a volume estimation unit 63.
[0147] The bucket state estimation unit 61 is configured to estimate the state of the bucket 6. The state of the bucket 6 is estimated, for example, by recognizing the shape of the bucket 6 and the current position and attitude of the bucket 6. In this embodiment, information on the shape of the bucket 6 is pre-stored in a storage device as design data such as a CAD model. Information on the current position and attitude of the bucket 6 is derived from the output of the attitude sensor. That is, the bucket state estimation unit 61 can derive the current position and attitude of the bucket 6 based on the output of the attitude sensor. The attitude sensor is, for example, at least one of a boom angle sensor S1, an arm angle sensor S2, a bucket angle sensor S3, a machine body inclination sensor S4, and a turning state sensor S5.
[0148] Estimating the state of the bucket 6 means, for example, determining the coordinates of a point cloud related to the outer surface of the bucket 6 in a predetermined coordinate system. The predetermined coordinate system is, for example, a three-dimensional orthogonal coordinate system Σarm with the position of the shape estimation device S10 as its origin. In this manner, the bucket state estimation unit 61 calculates the coordinates related to the outer surface of the bucket 6 using the angle of the bucket 6 with respect to the arm 5 and the CAD model.
[0149] The bucket state estimation unit 61 may be configured to derive the current attitude of the bucket 6 without using the output of the attitude sensor. For example, the bucket state estimation unit 61 may be configured to derive the current attitude of the bucket 6 based on a CAD model of the bucket 6 stored in advance in a storage device and the output of a LIDAR as the shape estimation device S10. Specifically, the bucket state estimation unit 61 may be configured to derive the current attitude of the bucket 6 based on the CAD model of the bucket 6 and point cloud data related to the tip of the bucket 6, the right side, left side, front side, or rear side edge of the opening of the bucket 6, or a bucket link, etc., acquired by the shape estimation device S10. Alternatively, the bucket state estimation unit 61 may be configured to estimate the state of the bucket 6 based only on the output of a LIDAR as the shape estimation device S10. For example, the bucket state estimation unit 61 can acquire information on the shape of the bucket 6 by measuring the bucket 6 when no object such as soil or sand is taken in by a LIDAR as the shape estimation device S10. That is, the bucket state estimation unit 61 can generate a CAD model of the bucket 6 based on the output of the LIDAR serving as the shape estimation device S10.
[0150] The soil shape estimation unit 62 is configured to estimate the shape of an object taken into the bucket 6. In this embodiment, the soil shape estimation unit 62 estimates the surface shape of an object (e.g., soil, etc.) in the bucket 6 based on the output of the LIDAR serving as the shape estimation device S10.
[0151] Estimating the shape of the surface of the object contained in the bucket 6 means, for example, determining the coordinates of a group of points related to the surface of the object in a predetermined coordinate system. The predetermined coordinate system is, for example, a three-dimensional orthogonal coordinate system Σarm with the position of the shape estimation device S10 as the origin.
[0152] Fig. 6 shows an example of a cross section of monitoring range R1 of shape estimation device S10 by a dot pattern. As shown in Fig. 6, the LIDAR as shape estimation device S10 is attached to the ventral surface of arm 5 so as to acquire point cloud data related to the surface of the soil taken into bucket 6. Specifically, the LIDAR as shape estimation device S10 is attached to the ventral surface of arm 5 so as to acquire point cloud data related to the surface of the soil taken into bucket 6, which is closer to pin P7 connecting arm 5 and bucket 6.
[0153] The point cloud data acquired by the LIDAR as the shape estimation device S10 includes point cloud data related to the ground as well as the bucket 6 and objects (such as soil and sand) contained in the bucket 6, and also includes point cloud data caused by noise. Therefore, in this embodiment, the sediment shape estimation unit 62 uses a filter such as a pass-through filter to remove these unnecessary point cloud data. Specifically, the sediment shape estimation unit 62 roughly removes point cloud data related to objects (hereinafter referred to as "non-target objects") other than the soil contained in the bucket 6 and the bucket 6 itself (hereinafter referred to as "target object") by setting a threshold value used in the pass-through filter based on the positional relationship between the shape estimation device S10 and the bucket 6. Then, the sediment shape estimation unit 62 clusters the remaining point cloud data that has not been removed, i.e., the point cloud data related to the target object, and extracts the maximum cluster, thereby extracting the point cloud data related to the target object.
[0154] The volume estimation unit 63 is configured to estimate the volume of an object taken into the bucket 6. In this embodiment, the volume estimation unit 63 is configured to estimate the volume of an object taken into the bucket 6 by combining point cloud data (first point cloud data) related to the outer surface of the bucket 6 derived by the bucket state estimation unit 61 and point cloud data (second point cloud data) related to a non-target object derived by the soil shape estimation unit 62. This is because it can be determined that the volume of a space surrounded by the first point cloud data and the second point cloud data corresponds to the volume of an object taken into the bucket 6. Note that the combination of the first point cloud data and the second point cloud data means, for example, integrating the two point cloud data into a set of point cloud data, that is, third point cloud data.
[0155] Specifically, the volume estimation unit 63 normalizes the three-dimensional shape represented by the third point cloud data by voxelizing the three-dimensional shape.
[0156] Then, as shown in FIG. 7, the volume estimation unit 63 calculates the three-dimensional distance h in the Z-axis direction between a voxel V1 (with a diagonal line pattern) generated from the CAD model of the bucket 6 and a voxel V2 (with a dot pattern) generated from the point cloud data representing the surface (upper surface) of the soil and sand taken into the bucket 6. i(i is an integer from 0 to N), the volume V of the soil taken into the bucket 6 is calculated. FIG. 7 shows a cross section in the XZ plane of the three-dimensional shape represented by the third point cloud data. This three-dimensional shape includes the three-dimensional shape of the bucket 6 and the three-dimensional shape of the soil taken into the bucket 6. The Z axis is one of the three axes constituting the three-dimensional orthogonal coordinate system Σarm, for example, an axis extending parallel to the central axis of the arm 5. The X axis is another of the three axes constituting the three-dimensional orthogonal coordinate system Σarm, for example, an axis extending in the front-rear direction of the upper rotating body 3 in a top view. The Y axis (not shown) is another of the three axes constituting the three-dimensional orthogonal coordinate system Σarm, for example, an axis extending in the width direction of the upper rotating body 3. N is the number of voxels V1 in the XY plane. The number of voxels V1 in the XY plane is counted as one when multiple voxels V1 overlap in the Z axis direction.
[0157] In general terms, the volume estimation unit 63 estimates the entire volume of the object including the bucket 6 and the soil and sand contained in the bucket 6, then calculates the volume of the bucket 6, and then estimates the volume of the soil and sand by subtracting the volume of the bucket 6 from the volume of the entire object.
[0158] Specifically, the volume estimation unit 63 calculates the volume V using the following formula (1): In formula (1), S represents the base area of the voxel (unit area in the XY plane).
[0159]
number
[0160] Incidentally, the controller 30 (shape estimation unit 60) can estimate the volume V at any timing, but may be configured to estimate the volume V at a predetermined timing. For example, the controller 30 may be configured to continuously derive the attitude of the bucket 6 based on the output of the attitude sensor, and estimate the volume V when the attitude of the bucket 6 becomes a predetermined attitude.
[0161] Furthermore, the controller 30 (shape estimation unit 60) may automatically operate the excavation attachment so that the bucket 6 assumes a predetermined posture. For example, the shape estimation unit 60 may extend and retract at least one of the boom cylinder 7, the arm cylinder 8, and the bucket cylinder 9, regardless of whether or not the operator of the shovel 100 operates the operation device 26, so that the posture of the bucket 6 assumes a predetermined posture.
[0162] Furthermore, the controller 30 (shape estimation unit 60) may set the volume V to a statistical value calculated based on multiple estimation results. The statistical value is, for example, an average value, a maximum value, a minimum value, a mode, or a median. For example, the shape estimation unit 60 may set the final volume V to an average value of the volume V estimated when the bucket 6 is in a predetermined first posture and the volume V estimated when the bucket 6 is in a predetermined second posture. Alternatively, the shape estimation unit 60 may set the final volume V to a maximum value among the volume V estimated when the bucket 6 is in a predetermined first posture, the volume V estimated when the bucket 6 is in a predetermined second posture, and the volume V estimated when the bucket 6 is in a predetermined third posture.
[0163] Alternatively, the controller 30 (shape estimation unit 60) may be configured to estimate the surface shape of the object in the bucket 6 multiple times based on the output of the LIDAR as the shape estimation device S10. For example, the shape estimation unit 60 may estimate the surface shape of the soil in the bucket 6 repeatedly at a predetermined time interval while the boom raising rotation is being performed. The shape estimation unit 60 may be configured to recalculate the volume V of the soil when it is determined that the surface shape of the soil has changed. Specifically, the shape estimation unit 60 may be configured to estimate the volume V of the soil when it estimates the surface shape of the soil for the first time after the boom raising rotation is started. The shape estimation unit 60 determines whether the surface shape has changed each time it estimates the surface shape of the soil thereafter, and when it determines that the surface shape has not changed, that is, when it is determined that the soil has not spilled out of the bucket 6, it omits recalculation of the volume V of the soil. On the other hand, when the shape estimation unit 60 determines that the shape of the surface has changed, that is, when it is determined that some of the soil has spilled out of the bucket 6, the shape estimation unit 60 recalculates the volume V of the soil based on the newly estimated shape of the surface of the soil. With this configuration, the shape estimation unit 60 can efficiently and accurately estimate the volume V of the soil to be loaded into the dump truck, for example, even if the soil spills out of the bucket 6 during boom raising and swinging. In other words, the shape estimation unit 60 can prevent the volume of the soil that has spilled out of the bucket 6 during boom raising and swinging from being included in the volume V of the soil to be loaded into the dump truck.
[0164] Next, another example of the configuration related to the shape estimation function of the shovel 100 will be described with reference to Fig. 8. Fig. 8 is a side view of the shovel 100. A first shape estimation device S10A and a second shape estimation device S10C are attached to the shovel 100 shown in Fig. 8 as the shape estimation device S10.
[0165] Specifically, the first shape estimation device S10A is configured to estimate the shape of an object taken into the bucket 6. In the example shown in FIG. 8, the first shape estimation device S10A is configured to include three RGB-D sensors attached to the ventral surface of the arm 5, and is configured to transmit acquired information to the controller 30. In FIG. 8, the dashed arrow extending from the first shape estimation device S10A toward the bucket 6 indicates that the first shape estimation device S10A is irradiating infrared rays for distance measurement in the direction of the bucket 6. The first shape estimation device S10A may be attached to other parts of the excavation attachment AT, such as the back or side of the arm 5, or the ventral surface, side, or back of the boom 4. Alternatively, the first shape estimation device S10A may be attached to the boom cylinder 7, the arm cylinder 8, the bucket cylinder 9, or the like.
[0166] Further, the first shape estimation device S10A is configured so that a specific part of the excavator 100, such as the front of the cabin 10, is included in the monitoring range. In the example shown in Fig. 8, the first shape estimation device S10A is configured so as to be able to recognize an AR (Augmented Reality) marker MK affixed to the front of the cabin 10. The first shape estimation device S10A can derive its own (the first shape estimation device S10A) current posture by recognizing the AR marker MK. In Fig. 8, the dashed arrow extending from the first shape estimation device S10A toward the cabin 10 indicates that the first shape estimation device S10A is capturing an image of the AR marker MK.
[0167] 8, the first shape estimation device S10A includes an RGB-D sensor for measuring the shape of the object taken in the bucket 6, and an RGB-D sensor for capturing an image of the AR marker MK. However, the first shape estimation device S10A may include an RGB-D sensor that can measure the shape of the object taken in the bucket 6 and capture an image of the AR marker MK. Alternatively, the RGB-D sensor for capturing an image of the AR marker MK may be replaced with a monocular camera. Alternatively, the RGB-D sensor for measuring the shape of the object taken in the bucket 6 may be replaced with a LIDAR, a stereo camera, or the like.
[0168] The first shape assumption device S10A may be configured to recognize a characteristic three-dimensional shape of a part of the shovel 100, instead of recognizing the AR marker MK. The characteristic three-dimensional shape of the part of the shovel 100 is, for example, a protrusion or recess at the front end of the lower part of the cabin 10, or a protrusion or recess at the front end of the revolving frame. Moreover, the first shape assumption device S10A may be configured to recognize a two-dimensional code such as a QR code (registered trademark) attached to the upper revolving body 3, instead of recognizing the AR marker MK. That is, the first shape assumption device S10A may be configured to recognize any information as long as it can derive its own position and attitude from the information acquired by itself.
[0169] The second shape estimation device S10C is configured to estimate the shape of the bucket 6. In the example shown in Fig. 8, the second shape estimation device S10C is configured with three RGB-D sensors attached to the lower front end of the cabin 10, and is configured to transmit acquired information to the controller 30. However, the second shape estimation device S10C may be attached to other parts of the upper rotating body 3, such as the upper front end of the cabin 10. In addition, the second shape estimation device S10C may be configured with one RGB-D sensor, or may be configured with one or more LIDARs or stereo cameras, etc.
[0170] In the example shown in FIG. 8, the bucket state estimation unit 61 is configured to be able to estimate the state of the bucket 6, that is, the shape of the bucket 6 and the current attitude of the bucket 6, based on the output of the second shape estimation device S10C.
[0171] Specifically, the bucket state estimation unit 61 estimates the state of the bucket 6 based on point cloud data regarding the front surface FS (see the thick dotted line in FIG. 8) of the bucket 6 acquired by an RGB-D sensor serving as the second shape estimation device S10C. Note that in FIG. 8, the dashed-dotted arrow extending from the second shape estimation device S10C toward the bucket 6 indicates that the second shape estimation device S10C is irradiating infrared rays for distance measurement in the direction of the bucket 6.
[0172] More specifically, the bucket state estimation unit 61 applies a RANSAC (Random sample consensus) algorithm to the point cloud data related to the bucket 6 to detect the front surface FS of the bucket 6. Then, the bucket state estimation unit 61 estimates the position and posture of the bucket 6 from the position and posture of the detected front surface FS. Then, the bucket state estimation unit 61 derives point cloud data (first point cloud data) related to the outer surface of the bucket 6 based on the estimated position and posture of the bucket 6 and a CAD model of the bucket 6.
[0173] The soil shape estimation unit 62 estimates the surface shape of the object (e.g., soil) contained in the bucket 6 based on the output of the RGB-D sensor serving as the first shape estimation device S10A. Specifically, the soil shape estimation unit 62 derives point cloud data (second point cloud data) relating to non-target objects other than the bucket 6 and the soil contained in the bucket 6 (i.e., the target object) based on the output of the RGB-D sensor serving as the first shape estimation device S10A.
[0174] The volume estimation unit 63 is configured to estimate the volume of an object taken into the bucket 6 by combining point cloud data (first point cloud data) regarding the outer surface of the bucket 6 derived by the bucket state estimation unit 61 and point cloud data (second point cloud data) regarding a non-target object derived by the soil shape estimation unit 62.
[0175] With the above-mentioned configuration, the controller 30 (shape estimation unit 60) can accurately estimate the volume V of the soil taken into the bucket 6.
[0176] Incidentally, the controller 30 (shape estimation unit 60) can estimate the volume V at any timing, but may be configured to estimate the volume V at a predetermined timing. For example, the controller 30 may be configured to continuously derive the attitude of the bucket 6 based on the output of the second shape estimation device S10C, and estimate the volume V when the attitude of the bucket 6 becomes a predetermined attitude.
[0177] Furthermore, the controller 30 (shape estimation unit 60) may set a statistical value calculated based on multiple estimation results as the volume V. The statistical value is, for example, an average value, a maximum value, a minimum value, a mode, or a median value.
[0178] 8, the attitude sensors (boom angle sensor S1, arm angle sensor S2, and bucket angle sensor S3) related to the excavation attachment may be omitted. This is because the controller 30 can derive the position and attitude of the arm 5 to which the first shape estimation device S10A is attached based on the output of the first shape estimation device S10A, and can derive the position and attitude of the boom 4 from the position and attitude of the arm 5. This is also because the controller 30 can derive the position and attitude of the bucket 6 based on the output of at least one of the first shape estimation device S10A and the second shape estimation device S10C. In other words, this is because the controller 30 can derive the attitude of the excavation attachment without using the output of the attitude sensors related to the excavation attachment.
[0179] However, the controller 30 (shape estimation unit 60) may be configured to estimate the state of the bucket 6 using the output of the attitude sensor related to the excavation attachment and the output of the shape estimation device S10. This is because the accuracy of estimating the state of the bucket 6 is improved by using two types of output.
[0180] [Configuration details for excavator soil weight detection function] Next, a detailed configuration of a soil weight detection function of a shovel 100 according to yet another embodiment of the present invention will be described with reference to Fig. 9. Fig. 9 is a diagram illustrating an example of a configuration part of the shovel 100 that is related to the soil weight detection function.
[0181] In the example shown in Figure 9, the shape estimation unit 60 has, in addition to a bucket state estimation unit 61, a soil shape estimation unit 62, and a volume estimation unit 63, a weight calculation unit 64, a maximum load capacity detection unit 65, a load capacity calculation unit 66, a remaining load capacity calculation unit 67, and a center of gravity calculation unit 68 as functional units related to the function of detecting the weight of the soil excavated by the bucket 6 (soil weight).
[0182] Here, an example of the operation of the excavator 100 for loading earth and sand (cargo) onto a dump truck will be described.
[0183] First, the shovel 100 excavates soil and sand with the bucket 6 by controlling the excavation attachment at the excavation position (excavation operation). Next, the shovel 100 rotates the upper rotating body 3 to move the bucket 6 from the excavation position to the soil discharge position (swing operation). The bed of the dump truck is disposed below the soil discharge position. Next, the shovel 100 controls the attachment at the soil discharge position to discharge the soil in the bucket 6, thereby loading the soil in the bucket 6 onto the bed of the dump truck (soil discharge operation). Next, the shovel 100 rotates the upper rotating body 3 to move the bucket 6 from the soil discharge position to the excavation position (swing operation). By repeating these operations, the shovel 100 loads the excavated soil and sand onto the bed of the dump truck.
[0184] The weight calculation unit 64 is configured to calculate the weight of the soil (cargo) in the bucket 6. In the example shown in Fig. 9, the weight calculation unit 64 calculates the weight of the soil based on the thrust of the boom cylinder 7. For example, the weight calculation unit 64 calculates the weight of the soil based on the thrust of the boom cylinder 7, the distance from the pin connecting the upper rotating body 3 and the boom 4 to the center of gravity of the soil, and an equation for the moment around the pin connecting the upper rotating body 3 and the boom 4.
[0185] The maximum load detection unit 65 is configured to detect the maximum load of the dump truck to be loaded with soil and sand. For example, the maximum load detection unit 65 identifies the dump truck to be loaded with soil and sand based on an image captured by the imaging device S6. "Based on an image captured by the imaging device S6" means, for example, using information obtained by performing one or more image processing operations on the image captured by the imaging device S6. Next, the maximum load detection unit 65 detects the maximum load of the dump truck based on the image of the identified dump truck. For example, the maximum load detection unit 65 determines the vehicle type (size, etc.) of the dump truck based on the image of the identified dump truck. The maximum load detection unit 65 has a table in which vehicle types and maximum loads are associated with each other, and determines the maximum load of the dump truck based on the vehicle type determined from the image and the table. The maximum load capacity and vehicle type of the dump truck may be inputted by the input device 42, and the maximum load capacity detection unit 65 may obtain the maximum load capacity of the dump truck based on the input information of the input device 42.
[0186] The load amount calculation unit 66 is configured to calculate the weight of the soil loaded on the dump truck. That is, every time the soil in the bucket 6 is discharged onto the bed of the dump truck, the load amount calculation unit 66 adds the weight of the soil in the bucket 6 calculated by the weight calculation unit 64 to the load amount (total weight) which is the total weight of the soil loaded onto the bed of the dump truck, to update the load amount. Note that when the target dump truck to load the soil is a new dump truck, the load amount is reset.
[0187] The remaining load calculation unit 67 is configured to calculate the difference between the maximum load of the dump truck detected by the maximum load detection unit 65 and the current load calculated by the load calculation unit 66 as the remaining load. The remaining load is the remaining weight of earth and sand that can be loaded onto the dump truck.
[0188] The center of gravity calculation unit 68 is configured to calculate the center of gravity of the soil and sand (cargo) in the bucket 6. The method of calculating the center of gravity of the soil and sand will be described later.
[0189] The display device 40 may display at least one of the weight of the soil in the bucket 6 calculated by the weight calculation unit 64, the maximum load capacity of the dump truck detected by the maximum load capacity detection unit 65, the load capacity of the dump truck (the total weight of soil loaded on the bed) calculated by the load capacity calculation unit 66, and the remaining load capacity of the dump truck (the remaining weight of soil that can be loaded) calculated by the remaining load capacity calculation unit 67.
[0190] In addition, the display device 40 may display at least one of the volume of the soil in the bucket 6 estimated by the volume estimation unit 63 and the density of the soil derived from the weight and volume of the soil in the bucket 6.
[0191] The shovel 100 may be configured to issue a warning on the display device 40 when the load exceeds the maximum load. The shovel 100 may be configured to issue a warning on the display device 40 when the calculated weight of earth and sand in the bucket 6 exceeds the remaining load. The warning does not necessarily have to be displayed on the display device 40, but may be output as sound by the sound output device 43. This allows the shovel 100 to prevent earth and sand from being loaded onto the dump truck in excess of the maximum load of the dump truck.
[0192] Here, a configuration example of the main screen 41V displayed on the display device 40 will be described with reference to Fig. 10. Information displayed on the main screen 41V in Fig. 10 includes, for example, the weight of soil and sand in the bucket 6 (current weight), the load of the dump truck (accumulated weight), the remaining load of the dump truck (remaining weight), the maximum load (maximum load weight), and information on the volume and density of the objects taken into the bucket 6.
[0193] The main screen 41V includes a date and time display area 41a, a driving mode display area 41b, an attachment display area 41c, a fuel efficiency display area 41d, an engine control status display area 41e, an engine operating time display area 41f, a coolant temperature display area 41g, a remaining fuel amount display area 41h, a rotation speed mode display area 41i, a remaining urea water amount display area 41j, a hydraulic oil temperature display area 41k, a camera image display area 41m, a current weight display area 41p, a cumulative weight display area 41q, a remaining weight display area 41s, a maximum load weight display area 41t, a volume display area 41u, and a density display area 41w.
[0194] The travel mode display area 41b, the attachment display area 41c, the engine control state display area 41e, and the rotation speed mode display area 41i are areas that display setting state information, which is information about the setting state of the shovel 100. The fuel consumption display area 41d, the engine operation time display area 41f, the coolant temperature display area 41g, the remaining fuel amount display area 41h, the remaining urea water amount display area 41j, the hydraulic oil temperature display area 41k, the current weight display area 41p, and the accumulated weight display area 41q are areas that display operating state information, which is information about the operating state of the shovel 100.
[0195] Specifically, the date and time display area 41a is an area for displaying the current date and time. The travel mode display area 41b is an area for displaying the current travel mode. The attachment display area 41c is an area for displaying an image representing the currently mounted end attachment. Fig. 10 shows a state in which an image representing the bucket 6 is displayed.
[0196] The fuel efficiency display area 41d is an area that displays fuel efficiency information calculated by the controller 30. The fuel efficiency display area 41d includes an average fuel efficiency display area 41d1 that displays a lifetime average fuel efficiency or an interval average fuel efficiency, and an instantaneous fuel efficiency display area 41d2 that displays an instantaneous fuel efficiency.
[0197] The engine control status display area 41e is an area that displays the control status of the engine 11. The engine operating time display area 41f is an area that displays the accumulated operating time of the engine 11. The coolant temperature display area 41g is an area that displays the current temperature state of the engine coolant. The remaining fuel amount display area 41h is an area that displays the remaining amount of fuel stored in the fuel tank. The rotation speed mode display area 41i is an area that displays the current rotation speed mode set by the engine rotation speed adjustment dial. The urea water remaining amount display area 41j is an area that displays the remaining amount of urea water stored in the urea water tank. The hydraulic oil temperature display area 41k is an area that displays the temperature state of the hydraulic oil in the hydraulic oil tank.
[0198] The camera image display area 41m is an area for displaying an image captured by the imaging device S6 as the first spatial recognition device. In the example of Fig. 10, the camera image display area 41m displays an image captured by the camera S6B. The image captured by the camera S6B is a rear image showing the space behind the excavator 100, and includes the image 3a of the counterweight.
[0199] The current weight display area 41p is an area for displaying the weight (current weight) of the soil in the bucket 6. Fig. 10 shows that the current weight is 550 kg.
[0200] The accumulated weight display area 41q is an area for displaying the load (accumulated weight) of the dump truck. Fig. 10 shows that the accumulated weight is 9500 kg.
[0201] The accumulated weight is reset every time the dump truck to be loaded is replaced. In this embodiment, the controller 30 is configured to automatically recognize the replacement of the dump truck and automatically reset the accumulated weight to zero. Specifically, the controller 30 recognizes the replacement of the dump truck by using an image captured by the imaging device S6. The controller 30 may recognize the replacement of the dump truck by using a communication device. Alternatively, the controller 30 may reset the accumulated weight when a reset button is pressed. The reset button may be a software button or a hardware button arranged on the input device 42, the left operation lever, the right operation lever, or the like.
[0202] With this configuration, the shovel 100 can prevent the loading of loads such as soil and sand onto the bed of the dump truck in excess of the maximum load weight of the dump truck. When the load exceeding the maximum load weight is detected by weight measurement at the platform, the driver of the dump truck must return to the loading yard and unload some of the load from the bed. The shovel 100 can prevent such load weight adjustment work from occurring.
[0203] The display device 40 may be configured to display the total weight of the cargo loaded onto the beds of one or more dump trucks during a predetermined period. The predetermined period may be, for example, the period from the start of a day's work to the end of a day's work, in order to allow an operator or manager to easily recognize the total weight of the cargo carried away from the work site by the day's work.
[0204] The controller 30 may be configured to recognize that the soil in the bucket 6 has been loaded onto the bed of the dump truck based on the image captured by the imaging device S6, and then calculate the current weight. This is to prevent soil that has been moved to a location other than the bed of the dump truck from being calculated as soil that has been loaded onto the dump truck.
[0205] The controller 30 may determine whether or not the soil in the bucket 6 has been loaded onto the bed of the dump truck based on the posture of the attachment. Specifically, the controller 30 may determine that the soil has been loaded onto the bed of the dump truck when, for example, the height of the bucket 6 exceeds a predetermined value (for example, the height of the bed of the dump truck) and the bucket 6 is opened.
[0206] The remaining weight display area 41s is an area for displaying the remaining weight. The maximum load weight display area 41t is an area for displaying the maximum load weight. Fig. 10 shows that the accumulated weight is 9500 kg, the remaining weight is 500 kg, and the maximum load weight is 10000 kg. However, the display device 40 may display the maximum load weight without displaying the remaining weight.
[0207] The volume display area 41u is an area for displaying the volume of soil and sand in the bucket 6. FIG. 3 The density display area 41w is an area for displaying the density of the soil in the bucket 6. FIG. 10 shows that the volume is 550 kg / m 3 This shows that.
[0208] A message is displayed in the message display area 41m1. For example, a message is displayed when the accumulated weight exceeds the maximum load weight. This allows the controller 30 to prompt the operator to perform loading and unloading work, and prevents overloading of the dump truck.
[0209] [Method of calculating soil weight in weight calculation unit 64] Next, a method for calculating the weight of earth and sand (cargo) in the bucket 6 by the weight calculation unit 64 of the shovel 100 will be described with reference to FIG. 9 and FIG.
[0210] Fig. 11 is a schematic diagram for explaining parameters related to calculation of soil weight. Fig. 11(a) shows the shovel 100, and Fig. 11(b) shows the vicinity of the bucket 6. In the following explanation, it is assumed that a pin P1, a bucket center of gravity G3, and a soil center of gravity Gs, which will be described later, are located on a horizontal line L1.
[0211] Here, the pin connecting the upper rotating body 3 and the boom 4 is defined as P1. The pin connecting the upper rotating body 3 and the boom cylinder 7 is defined as P2. The pin connecting the boom 4 and the boom cylinder 7 is defined as P3. The pin connecting the boom 4 and the arm cylinder 8 is defined as P4. The pin connecting the arm 5 and the arm cylinder 8 is defined as P5. The pin connecting the boom 4 and the arm 5 is defined as P6. The pin connecting the arm 5 and the bucket 6 is defined as P7. Furthermore, the center of gravity of the boom 4 is defined as G1. The center of gravity of the arm 5 is defined as G2. The center of gravity of the bucket 6 is defined as G3. The center of gravity of the soil (load) loaded in the bucket 6 is defined as Gs. The reference line L2 is a line that passes through the pin P7 and is parallel to the opening surface of the bucket 6. Furthermore, the distance between the pin P1 and the center of gravity G1 of the boom 4 is defined as D1. The distance between the pin P1 and the center of gravity G2 of the arm 5 is defined as D2. The distance between pin P1 and the center of gravity G3 of bucket 6 is defined as D3. The distance between pin P1 and the center of gravity Gs of the soil is defined as Ds. The distance between pin P1 and the line (dashed line) connecting pins P2 and P3 and pin P1 is defined as Dc. Furthermore, the force due to the cylinder pressure of boom cylinder 7 is defined as Fb (see arrow). Furthermore, the vertical component of the boom weight (gravity due to the weight of boom 4) perpendicular to the line connecting pin P1 and the boom center of gravity G1 is defined as W1a (see arrow). The vertical component of the arm weight (gravity due to the weight of arm 5) perpendicular to the line connecting pin P1 and the arm center of gravity G2 is defined as W2a. The weight of bucket 6 is defined as W6, and the weight of the soil (load) loaded on bucket 6 is defined as Ws (see arrow).
[0212] 11(a), the position of the pin P7 is calculated from the boom angle and the arm angle. That is, the position of the pin P7 is calculated based on the detection values of the boom angle sensor S1 and the arm angle sensor S2.
[0213] 11(b), the positional relationship between the pin P7 and the bucket center of gravity G3 (angle θ4 between the reference line L2 of the bucket 6 and the line connecting the pin P7 and the bucket center of gravity G3; distance D4 between the pin P7 and the bucket center of gravity G3) is a preset value. The positional relationship between the pin P7 and the soil center of gravity Gs (angle θ5 between the reference line L2 of the bucket 6 and the line connecting the pin P7 and the soil center of gravity Gs; distance D5 between the pin P7 and the soil center of gravity Gs) may be determined in advance, for example, experimentally and stored in the controller 30. That is, the controller 30 can estimate the positions of the soil center of gravity Gs and the bucket center of gravity G3 based on the output of the bucket angle sensor S3.
[0214] That is, the center of gravity calculation unit 68 can estimate the position of the soil center of gravity Gs in a predetermined coordinate system based on the detection values of the boom angle sensor S1, the arm angle sensor S2, and the bucket angle sensor S3. The predetermined coordinate system is, for example, a three-dimensional orthogonal coordinate system Σarm with the position of the shape estimation device S10 as the origin.
[0215] However, the center of gravity calculation unit 68 may estimate the center of gravity Gs of the soil based on the detection value of the LIDAR as the shape estimation device S10, or based on the detection value of the LIDAR as the shape estimation device S10 and the detection values of the boom angle sensor S1, the arm angle sensor S2, and the bucket angle sensor S3.
[0216] Next, the equation for the balance of each moment around pin P1 can be expressed by the following equation (A1).
[0217] Ws×Ds+W1a×D1+W2a×D2+W3×D3=Fb×Dc...(A1) When equation (A1) is expanded in terms of the soil weight Ws, it can be expressed as the following equation (A2).
[0218] Ws=(Fb×Dc-(W1a×D1+W2a×D2+W3×D3)) / Ds...(A2) Here, the force Fb due to the cylinder pressure of the boom cylinder 7 is calculated from at least one of the detection values of the boom rod pressure sensor S7R and the boom bottom pressure sensor S7B. The distance Dc and the vertical component W1a of the boom weight are calculated from the detection value of the boom angle sensor S1. The vertical component W2a of the arm weight and the distance D2 are calculated from the detection values of the boom angle sensor S1 and the arm angle sensor S2, respectively. The distance D1 and the bucket weight W3 (gravity due to the own weight of the bucket 6) are known values. Furthermore, the distance Ds and the distance D3 are also estimated by estimating the soil gravity center Gs and the bucket gravity center G3.
[0219] Therefore, the soil weight Ws can be calculated based on the detection value of the cylinder pressure of the boom cylinder 7 (the detection value of at least one of the boom rod pressure sensor S7R and the boom bottom pressure sensor S7B), the boom angle (the detection value of the boom angle sensor S1), and the arm angle (the detection value of the arm angle sensor S2). This allows the weight calculation unit 64 to calculate the soil weight Ws based on the soil gravity center Gs estimated by the gravity center calculation unit 68.
[0220] The weight calculation unit 64 preferably calculates the weight of soil and sand Ws when it is determined that the shovel 100 is performing a prescribed operation. Whether or not the shovel 100 is performing a prescribed operation can be determined by, for example, estimating the attitude of the bucket 6 based on the detected value of the pilot pressure of the bucket cylinder 9.
[0221] When the prescribed operation is being performed, the weight calculation unit 64 estimates the center of gravity of the soil and calculates the weight of the soil, assuming that the opening surface of the bucket 6 is horizontal. However, the weight calculation unit 64 may image the bucket 6 with the camera S6F that images the front, and estimate the attitude of the bucket 6 based on the image. The weight calculation unit 64 may also image the bucket 6 with the camera S6F, and estimate the center of gravity of the soil and calculate the weight of the soil when it is determined that the opening surface of the bucket 6 is horizontal based on the image.
[0222] 9 to 11, controller 30 is configured to calculate the center of gravity of the object (soil, sand, etc.) taken in bucket 6, and then calculate the weight of the object taken in bucket 6. Therefore, controller 30 can accurately derive the weight of the object taken in bucket 6. However, controller 30 may calculate the weight of the object taken in bucket 6 without calculating the center of gravity of the object (soil, sand, etc.) taken in bucket 6.
[0223] As described above, the excavator 100 according to the embodiment of the present invention includes the lower traveling body 1, the upper rotating body 3 rotatably mounted on the lower traveling body 1, an attachment attached to the upper rotating body 3, the bucket 6 constituting the attachment, a shape estimation device S10 as a spatial recognition device attached to the attachment, and the controller 30 as a control device that calculates the shape of an object taken into the bucket 6 based on the output of the shape estimation device S10. With this configuration, the excavator 100 can obtain the volume of the object taken into the bucket 6 from the shape of the object taken into the bucket 6.
[0224] The controller 30 may be configured to calculate the shape of the object taken into the bucket 6 based on the output of the shape estimation device S10 and the output of the attitude sensor. The attitude sensor is, for example, at least one of the boom angle sensor S1, the arm angle sensor S2, the bucket angle sensor S3, the machine body inclination sensor S4, and the turning state sensor S5. For example, the controller 30 can calculate the shape of the surface (upper surface) of the soil taken into the bucket 6 based on the output of the shape estimation device S10. The controller 30 can also derive the current position and attitude of the bucket 6 based on the output of the attitude sensor. That is, the controller 30 can derive the position and attitude of the inner surface of the bucket 6, which corresponds to the bottom surface (lower surface) of the soil taken into the bucket 6. As a result, the controller 30 can derive the shapes of the surface (upper surface) and bottom surface (lower surface) of the soil taken into the bucket 6, that is, the overall shape of the outer surface of the soil taken into the bucket 6. With this configuration, the shovel 100 can obtain the volume of the object taken into the bucket 6 from the overall shape of the outer surface of the object taken into the bucket 6. In this case, if the density of the soil in the bucket 6 has been input in advance to the controller 30, the shovel 100 can also calculate the weight of the soil in the bucket 6 based on the calculated volume.
[0225] The shape estimation device S10 may include a spatial recognition device attached to the attachment and a spatial recognition device attached to the upper rotating body 3. For example, as shown in FIG. 8, the shape estimation device S10 may include a first shape estimation device S10A attached to the ventral surface of the arm 5 and a second shape estimation device S10C attached to the lower front end of the cabin 10. With this configuration, the excavator 100 can measure the bucket 6 not only by the spatial recognition device attached to the attachment but also by the spatial recognition device attached to the upper rotating body 3, so that the position and shape of the bucket 6 can be estimated more accurately. In particular, since the spatial recognition device attached to the upper rotating body 3 can measure the front surface FS of the bucket 6, the excavator 100 can estimate the position and shape of the bucket 6 more accurately.
[0226] The shape estimation device S10 as a spatial recognition device attached to an attachment may include a first spatial recognition device including the bucket 6 in its monitoring range and a second spatial recognition device including the upper rotating body 3 in its monitoring range. Alternatively, the shape estimation device S10 may be one or more spatial recognition devices including the bucket 6 and the upper rotating body 3 in its monitoring range. For example, as shown in FIG. 8, the first shape estimation device S10A as a spatial recognition device may include an RGB-D sensor as a first spatial recognition device including the bucket 6 in its monitoring range and an RGB-D sensor as a second spatial recognition device including the upper rotating body 3 in its monitoring range. The RGB-D sensor including the bucket 6 in its monitoring range and the RGB-D sensor including the upper rotating body 3 in its monitoring range may be the same RGB-D sensor or may be separate RGB-D sensors. With this configuration, the shape estimation device S10 attached to an attachment can measure not only the state of the bucket 6 but also the state of the shape estimation device S10 itself. The state of the shape estimation device S10 itself is, for example, the position and attitude of the shape estimation device S10. Therefore, in this configuration, the attitude sensor may be omitted. This is because the shape estimation device S10 attached to the attachment can recognize the positions and attitudes of the boom 4, the arm 5, and the bucket 6 based on the information acquired by the shape estimation device S10 itself.
[0227] The controller 30 may be configured to estimate the volume of an object taken into the bucket 6 by using design data of the bucket 6. The design data of the bucket 6 includes, for example, the width and length of the bucket 6, the angle between the opening surface and the front surface FS, and the like. The design data of the bucket 6 may be stored, for example, as a CAD model in a storage device mounted on the excavator 100. With this configuration, the controller 30 can derive the overall position and attitude of the bucket 6 simply by acquiring information on the position and attitude of a part of the bucket 6, such as the front surface FS of the bucket 6. Then, the controller 30 can derive the shape of the object taken into the bucket 6 (particularly, the shape of a part not measured by the shape estimation device S10, such as the bottom surface of the object taken into the bucket 6) from the overall position and attitude of the bucket 6. As a result, the controller 30 can recognize the overall shape of the outer surface of the object taken into the bucket 6, and can derive the volume of the object from the overall shape.
[0228] The controller 30 may be configured to estimate the volume of the object taken into the bucket 6 based on the output of the shape estimation device S10 at a plurality of time points. In this case, the posture of the bucket 6 is different at each time point. For example, the controller 30 may determine the larger of the volume V estimated when the bucket 6 is in a predetermined first posture at a first time point and the volume V estimated when the bucket 6 is in a predetermined second posture at a second time point as the final volume V. Alternatively, the controller 30 may determine the final volume V as the minimum value of the volume V estimated when the bucket 6 is in a predetermined first posture at a first time point, the volume V estimated when the bucket 6 is in a predetermined second posture at a second time point, and the volume V estimated when the bucket 6 is in a predetermined third posture at a third time point. With this configuration, the controller 30 can improve the accuracy of the estimated volume V. This is because it is possible to suppress or prevent the value of the final volume V from being determined by an inappropriate value of the volume V estimated at one time point.
[0229] The controller 30 may be configured to calculate the weight of an object taken into the bucket 6 based on the pressure of hydraulic oil in a hydraulic actuator that drives the attachment, and to calculate the density of the object based on the weight and volume of the object taken into the bucket 6. For example, the controller 30 may calculate the weight of soil taken into the bucket 6 based on the boom bottom pressure, and calculate the density of the soil based on the weight of the soil and the volume of the soil derived by the above-mentioned processing. With this configuration, the controller 30 can derive the density of the object taken into the bucket 6. Then, for example, after the controller 30 has once derived the density of the object, it can calculate the weight of the object by simply deriving the volume of the object without deriving the weight of the object every time a boom raising operation is performed.
[0230] The controller 30 may be configured to derive characteristics of the soil taken into the bucket 6 based on the density of the soil. For example, the controller 30 may use the density of the soil derived in the above-mentioned process as a search key, and refer to a soil characteristics table pre-stored in a storage device mounted on the shovel 100 to derive soil characteristics corresponding to the density. With this configuration, the controller 30 can present, for example, information on the derived soil characteristics to the operator of the shovel 100. Alternatively, the controller 30 can adjust the movement of the shovel 100, which is realized by the machine guidance function or the machine control function, in accordance with the derived soil characteristics.
[0231] The present embodiment has been described above with reference to specific examples. However, the present invention is not limited to these specific examples. Design modifications made by a person skilled in the art to these specific examples are also included within the scope of the present invention as long as they have the characteristics of the present invention. The elements and their arrangements, conditions, shapes, etc. of each of the above-mentioned specific examples are not limited to those exemplified, and may be modified as appropriate. The elements of each of the above-mentioned specific examples may be combined as appropriate as long as no technical contradiction occurs. [Explanation of symbols]
[0232] 1···Lower traveling body 1L, 1R···Travel hydraulic motor 2···Slewing mechanism 2A···Slewing hydraulic motor 2A1···First port 2A2···Second port 3···Upper rotating body 4···Boom 5···Arm 6···Bucket 7···Boom cylinder 8···Arm cylinder 9···Bucket cylinder 10··Cabin 11··Engine 13···Regulator 14···Main pump 15···Pilot pump 18L, 18R···Throttle 19L, 19R··Control pressure sensor 21, 22··Hydraulic pressure sensor 23, 24··Relief valve 26···Operating device 28··Discharge pressure sensor 29, 29A to 29C··Operating pressure sensor 30··Controller 31AL, 31AR, 31BL, 31BR, 31CL, 31CR... Proportional valve 32AL, 32AR, 32BL, 32BR, 32CL, 32CR... Shuttle valve 33AL, 33AR, 33BL, 33BR, 33CL, 33CR... Proportional valve 40... Display device 42... Input device 43... Audio output device 47... Storage device 50... Machine guidance section 51... Position calculation section 52... Distance calculation section 53... Information transmission section 54... Automatic control section 55... Swing angle calculation section 56... Relative angle calculation section 60... Shape estimation section 61... Bucket state estimation section 62... Soil shape estimation section 63... Volume estimation section 64... Weight calculation section 64... Weight calculation section 65...Maximum load amount detection section 66...Load amount calculation section 67...Remaining load amount calculation section 68...Center of gravity calculation section 100...Shovel 171~176...Control valve PS...Positioning device S1...Boom angle sensor S2...Arm angle sensor S3...Bucket angle sensor S4...Machine body inclination sensor S5...Turning state sensor S6...Imaging device S6B, S6F, S6L, S6R...Camera S7B...Boom bottom pressure sensor S7R...Boom rod pressure sensor S8B...Arm bottom pressure sensor S8R...Arm rod pressure sensor S9B...Bucket bottom pressure sensor S9R...Bucket rod pressure sensor S10...Shape estimation device S10A...First shape estimation device S10C...Second shape estimation device T1...Communication device
Claims
1. a lower running body; an upper rotating body rotatably mounted on the lower traveling body; an attachment attached to the upper rotating body; a bucket constituting the attachment; and a first spatial recognition device attached to the attachment; A second spatial recognition device attached to the upper rotating body; and a control device that, when an object is taken into the bucket, calculates the shape of the object taken into the bucket based on the output of the first spatial recognition device, whose monitoring range includes the top surface of the object taken into the bucket, and the output of the second spatial recognition device, whose monitoring range includes the outer surface of the bucket, which is not measured by the first spatial recognition device. Shovel.
2. Equipped with a posture sensor, the control device calculates the shape of the object taken into the bucket based on the output of the first spatial recognition device, the output of the second spatial recognition device, and the output of the attitude sensor. The shovel according to claim 1.
3. a lower running body; an upper rotating body rotatably mounted on the lower traveling body; an attachment attached to the upper rotating body; a bucket constituting the attachment; and a first spatial recognition device attached to the attachment; A second spatial recognition device attached to the upper rotating body; and a control device that, when an object is taken into the bucket, determines sediment information based on the output of the first spatial recognition device, which includes within its monitoring range the top surface of the object taken into the bucket, and the output of the second spatial recognition device, which monitors the outer surface of the bucket that is not measured by the first spatial recognition device. Shovel.
4. The first spatial recognition device includes the upper rotating body within a monitoring range. The shovel according to any one of claims 1 to 3.
5. The first spatial recognition device is one or more spatial recognition devices that include the bucket and the upper rotating body in a monitoring range. A shovel according to any one of claims 1 to 4.
6. The control device estimates the state of the bucket based on point cloud data related to the front of the bucket acquired by the second spatial recognition device. A shovel according to any one of claims 1 to 5.
7. When estimating the volume of the object taken into the bucket by a single excavation operation, the control device estimates the volume of the object taken into the bucket based on the output of the first spatial recognition device and the output of the second spatial recognition device at multiple points in time before an earth-discharging operation is performed, The bucket attitude is different at each point in time. A shovel according to any one of claims 1 to 6.
8. The first spatial recognition device includes a spatial recognition device that includes the front of the cabin in its monitoring range, and is configured to derive the position and attitude of the first spatial recognition device from acquired information. A shovel according to any one of claims 1 to 7.
9. The information acquired by the first spatial recognition device is information that can be acquired by the first spatial recognition device recognizing an AR marker or a two-dimensional code attached to the front of the cabin, The shovel according to claim 8.
Citation Information
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