Excavator

Abstract

To provide an excavator capable of evaluating the stability of the excavator regardless of the inclination of the excavator.SOLUTION: An excavator 100 in an embodiment of the disclosure includes: an undercarriage 1; an upper revolving body 3 that is mounted on the undercarriage 1 rotatably; an attachment AT that is attached to the upper revolving body 3, and includes a boom 4, an arm 5, and a bucket 6; and a controller 30 that estimates the volume of earth and sand lifted by the attachment AT using the bucket 6, and based on the estimated volume of earth and sand, evaluates the stability of the posture of the excavator including the undercarriage 1 and the upper revolving body 3.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a shovel. [Background technology]

[0002] For example, a technique is known that uses an inclination sensor to detect the inclination of the machine body forward (toward the boom) (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Unexamined Patent Publication No. 11722 / 1983 Summary of the Invention [Problem to be solved by the invention]

[0004] However, with the above-mentioned technology, it is not possible to evaluate whether the stability of the shovel's posture has decreased until the rear of the lower running body 1 has lifted off and the machine body has actually tilted.

[0005] In view of the above problems, an object of the present invention is to provide a technique capable of evaluating the stability of a shovel regardless of the inclination of the machine body. [Means for solving the problem]

[0006] In order to achieve the above object, in one embodiment of the present disclosure, A lower running body; An upper rotating body rotatably mounted on the lower traveling body; A work attachment attached to the upper rotating body and including a boom, an arm, and a bucket; a control device that estimates a volume of soil to be lifted by the working attachment using the bucket, and evaluates the stability of an attitude of a machine body including the lower traveling body and the upper rotating body based on the estimated volume of soil. 、 The stability of the attitude of the aircraft is an index showing the resistance of the aircraft to tipping over. R, Shovel provided. Effect of the Invention

[0007] According to the above-described embodiment, the stability of the shovel can be evaluated regardless of the inclination of the machine body. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is an external view showing an example of a shovel. [Diagram 2] FIG. 2 is a block diagram showing an example of a configuration of a shovel. [Diagram 3] 11A to 11C are diagrams illustrating an example of a method for evaluating the stability of the posture of a shovel. [Figure 4] 13A to 13C are diagrams illustrating another example of a method for evaluating the stability of the posture of a shovel. [Diagram 5] FIG. 13 is a block diagram showing another example of the configuration of the shovel. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment will be described with reference to the drawings.

[0010] [Outline of the excavator] First, an overview of the shovel according to this embodiment will be described with reference to FIG.

[0011] FIG. 1 is an external view showing an example of a shovel 100 according to this embodiment.

[0012] As shown in Fig. 1, an excavator 100 according to this embodiment includes a lower traveling body 1, an upper rotating body 3 mounted on the lower traveling body 1 so as to be rotatable via a rotating mechanism 2, an attachment AT for performing various tasks, and a cabin 10. Hereinafter, the front of the shovel 100 (upper rotating body 3) corresponds to the direction in which the attachment for the upper rotating body 3 extends when the shovel 100 is viewed in a plan view (top view) from directly above along the rotation axis of the upper rotating body 3. In addition, the left and right sides of the shovel 100 (upper rotating body 3) correspond to the left and right sides, respectively, as viewed from an operator seated in a driver's seat in the cabin 10.

[0013] The lower traveling body 1 includes, for example, a pair of left and right crawlers 1C. The lower traveling body 1 causes the excavator 100 to travel by hydraulically driving each of the crawlers 1C by a left traveling hydraulic motor 1ML and a right traveling hydraulic motor 1MR (see FIGS. 2 and 3).

[0014] The upper rotating body 3 rotates relative to the lower traveling body 1 as a result of the rotating mechanism 2 being hydraulically driven by the rotating hydraulic motor 2A.

[0015] The attachment AT (an example of a work attachment) includes a boom 4 , an arm 5 , and a bucket 6 .

[0016] A boom 4 is 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 attached to the tip of the boom 4 so as to be able to rotate up and down, and a bucket 6 is attached to the tip of the arm 5 so as to be able to rotate up and down.

[0017] The bucket 6 is an example of an end attachment. The bucket 6 is used, for example, for excavation work. In addition, instead of the bucket 6, another end attachment may be attached to the tip of the arm 5 depending on the work content, etc. The other end attachment may be, for example, another type of bucket, such as a large bucket, a slope bucket, or a dredging bucket. The other end attachment may be a type of end attachment other than a bucket, such as an agitator, a breaker, or a grapple.

[0018] The boom 4, the arm 5, and the bucket 6 are hydraulically driven by a boom cylinder 7, an arm cylinder 8, and a bucket cylinder 9, which serve as hydraulic actuators, respectively.

[0019] The shovel 100 may be configured such that some of the driven elements, such as the lower traveling body 1, the upper rotating body 3, the boom 4, the arm 5, and the bucket 6, are electrically driven. In other words, the shovel 100 may be a hybrid shovel, an electric shovel, or the like, in which some of the driven elements are driven by an electric actuator.

[0020] The cabin 10 is a cockpit where an operator sits, and is mounted on the front left side of the upper rotating body 3.

[0021] As described below, when the excavator 100 is remotely operated or operates fully automatically, the cabin 10 may be omitted.

[0022] Furthermore, the shovel 100 may be equipped with, for example, a communication device 60 and may be capable of communicating with an external device via a predetermined communication line.

[0023] The communication line includes, for example, a wide area network (WAN). The wide area network may include, for example, a mobile communication network with a base station as a terminal. The wide area network may also include, for example, a satellite communication network using a communication satellite above the shovel 100. The wide area network may also include, for example, the Internet network. The communication line may also include, for example, a local area network (LAN) of a facility in which the management device 200 is installed. The local network may be a wireless line, a wired line, or a line including both. The communication line NW may also include, for example, a short-distance communication line based on a predetermined wireless communication method such as WiFi or Bluetooth (registered trademark).

[0024] The external device is, for example, a management device that manages (monitors) the operating status and operational status of the shovel 100. This enables the shovel 100 to transmit (upload) various information to the management device and receive various signals (for example, information signals and control signals) from the management device.

[0025] The management device is, for example, a cloud server or an on-premise server installed in a remote location different from the work site of the shovel 100. The management device may also be, for example, an edge server installed inside the work site of the shovel 100 (for example, a management office for the work site) or in a location relatively close to the work site (for example, a communication facility such as a nearby base station). The management device may also be a management terminal device used at the work site.

[0026] Furthermore, the external device may be, for example, a terminal device (user terminal) used by a user of the shovel 100. The user of the shovel 100 includes, for example, an operator, a serviceman, a manager, an owner, and the like of the shovel 100. This enables the shovel 100 to transmit various information to the user terminal and provide information about the shovel 100 to the user of the shovel 100.

[0027] In response to the operation of an operator in the cabin 10, the shovel 100 operates actuators (e.g., hydraulic actuators) to drive operating elements (hereinafter referred to as "driven elements") such as the lower running body 1, upper rotating body 3, boom 4, arm 5, and bucket 6.

[0028] Further, instead of or in addition to being configured to be operable by an operator in the cabin 10, the shovel 100 may be configured to be remotely operable from outside the shovel 100. When the shovel 100 is remotely operated, the inside of the cabin 10 may be unmanned. In the following description, it is assumed that the operation of the operator includes at least one of the operation of the operating device 26 by the operator in the cabin 10 and the remote operation by an external operator.

[0029] The remote operation includes, for example, a mode in which the shovel 100 is operated by an input from a user (operator) regarding the actuator of the shovel 100 performed in a predetermined external device (for example, the above-mentioned management device). In this case, the shovel 100 transmits image information (hereinafter, "surrounding image") of the surroundings of the shovel 100 based on the output of the imaging device S6 described later to the external device, and the image information may be displayed on a display device (hereinafter, "display device for remote operation") provided in the external device. In addition, various information images (information screens) displayed on the output device 50 in the cabin 10 of the shovel 100 may also be displayed on the display device for remote operation of the external device. This allows the operator of the external device to remotely operate the shovel 100 while checking the display contents, such as the surrounding image showing the state of the surroundings of the shovel 100 and various information images displayed on the display device for remote operation. The shovel 100 may operate actuators and drive driven elements such as the lower traveling body 1, upper rotating body 3, boom 4, arm 5, and bucket 6 in response to a remote control signal indicating the content of the remote control received from an external device.

[0030] Further, the remote operation may include, for example, a mode in which the shovel 100 is operated by an external voice input or gesture input to the shovel 100 by a person (e.g., a worker) around the shovel 100. Specifically, the shovel 100 recognizes voices uttered by surrounding workers or gestures made by the workers through a voice input device (e.g., a microphone) or an imaging device mounted on the shovel 100 (the shovel's own machine). Then, the shovel 100 may operate actuators according to the contents of the recognized voices or gestures, and drive driven elements such as the lower traveling body 1, the upper rotating body 3, the boom 4, the arm 5, and the bucket 6.

[0031] The shovel 100 may automatically operate the actuators regardless of the contents of the operation by the operator. This allows the shovel 100 to realize a function of automatically operating at least some of the driven elements such as the lower traveling body 1, the upper rotating body 3, the boom 4, the arm 5, and the bucket 6, i.e., a so-called "automatic driving function" or "machine control (MC) function."

[0032] The automatic operation function may include a function of automatically operating a driven element (actuator) other than the driven element (actuator) to be operated in response to an operator's operation of the operating device 26 or remote operation, i.e., a so-called "semi-automatic operation function" or "operation support type MC function". The automatic operation function may also include a function of automatically operating at least a part of a plurality of driven elements (hydraulic actuators) on the premise that there is no operation or remote operation of the operating device 26 by the operator, i.e., a so-called "fully automatic operation function" or "fully automatic type MC function". In the excavator 100, when the fully automatic operation function is enabled, the inside of the cabin 10 may be unmanned. The semi-automatic operation function, the fully automatic operation function, etc. may also include a mode in which the operation content of the driven element (actuator) to be the target of automatic operation is automatically determined according to a rule defined in advance. In addition, the semi-automatic driving function and the fully automatic driving function may include a mode in which the shovel 100 autonomously makes various decisions and autonomously determines the operation content of the driven element (hydraulic actuator) that is the target of the automatic driving based on the results of those decisions (so-called "autonomous driving function").

[0033] [An example of a shovel configuration] Next, an example of the configuration of the shovel 100 according to this embodiment will be described with reference to FIG.

[0034] Fig. 2 is a block diagram showing an example of the configuration of the excavator 100 according to this embodiment. In Fig. 2, paths through which mechanical power is transmitted are indicated by double lines, paths through which high-pressure hydraulic oil for driving the hydraulic actuator flows are indicated by solid lines, paths through which pilot pressure is transmitted are indicated by dashed lines, and paths through which electrical signals are transmitted are indicated by dotted lines. The same applies to Fig. 5 described below.

[0035] The shovel 100 includes various components, such as a hydraulic drive system for hydraulically driving the driven elements, an operation system for operating the driven elements, a user interface system for exchanging information with the user, a communication system for communicating with the outside world, and a control system for various controls.

[0036] <Hydraulic drive system> 2, the hydraulic drive system of the excavator 100 according to this embodiment includes hydraulic actuators that hydraulically drive each of the driven elements, such as the lower traveling body 1 (left and right crawlers 1C), upper rotating body 3, boom 4, arm 5, and bucket 6, as described above. The hydraulic actuators include traveling hydraulic motors 1ML, 1MR, swing hydraulic motor 2A, boom cylinder 7, arm cylinder 8, and bucket cylinder 9. The hydraulic drive system of the excavator 100 according to this embodiment also includes an engine 11, a regulator 13, a main pump 14, and a control valve 17.

[0037] The engine 11 is a prime mover and a main power source in the hydraulic drive system. The engine 11 is, for example, a diesel engine that uses light oil as fuel. The engine 11 is mounted, for example, on the rear of the upper rotating body 3. 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.

[0038] The excavator 100 may be equipped with another prime mover instead of or in addition to the engine 11. The other prime mover is, for example, an electric motor capable of driving the main pump 14 and the pilot pump 15.

[0039] The regulator 13 controls (adjusts) the discharge amount of the main pump 14 under the control of the controller 30. For example, the regulator 13 adjusts the angle of the swash plate of the main pump 14 (hereinafter, the “tilt angle”) in response to a control command from the controller 30.

[0040] The main pump 14 supplies hydraulic oil to the control valve 17 through a high-pressure hydraulic line. The main pump 14 is mounted, for example, on the rear of the upper rotating body 3, similar to the engine 11. As described above, the main pump 14 is driven by the engine 11. 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).

[0041] The control valve 17 is a hydraulic control device that controls the hydraulic actuators in response to the contents of the operator's operation on the operating device 26 or remote operation, or operation commands related to the automatic operation function output from the controller 30. The control valve 17 is mounted, for example, in the center of the upper rotating body 3. 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 each hydraulic actuator in response to the operator's operation or operation commands output from the controller 30. Specifically, the control valve 17 includes a plurality of control valves (also referred to as "directional control valves") 17A to 17F that control the flow rate and flow direction of the hydraulic oil supplied from the main pump 14 to each hydraulic actuator.

[0042] The control valve 17A is configured to supply hydraulic oil to the traveling hydraulic motor 1ML and to discharge the hydraulic oil from the traveling hydraulic motor 1ML and return it to the tank. This allows the control valve 17B to drive the traveling hydraulic motor 1ML by pilot pressure supplied from the operating device 26 or the hydraulic control valve 31.

[0043] The control valve 17B is configured to supply hydraulic oil to the traveling hydraulic motor 1MR and to discharge the hydraulic oil from the traveling hydraulic motor 1MR and return it to the tank. This allows the control valve 17B to drive the traveling hydraulic motor 1MR by pilot pressure supplied from the operating device 26 or the hydraulic control valve 31.

[0044] The control valve 17C is configured to be able to supply hydraulic oil to the swing hydraulic motor 2A, and to discharge the hydraulic oil from the swing hydraulic motor 2A and return it to the tank. This allows the control valve 17C to drive the swing hydraulic motor 2A by pilot pressure supplied from the operating device 26 or the hydraulic control valve 31.

[0045] The control valve 17D is configured to be able to supply hydraulic oil to the boom cylinder 7, and to discharge the hydraulic oil from the boom cylinder 7 and return it to the tank. This allows the control valve 17D to drive the boom cylinder 7 in response to the pilot pressure supplied from the operating device 26 or the hydraulic control valve 31.

[0046] The control valve 17E is configured to be able to supply hydraulic oil to the arm cylinder 8, and to discharge the hydraulic oil from the arm cylinder 8 and return it to the tank. This allows the control valve 17E to drive the arm cylinder 8 by pilot pressure supplied from the operation device 26 or the hydraulic control valve 31.

[0047] The control valve 17F is configured to be able to supply hydraulic oil to the bucket cylinder 9, and to discharge the hydraulic oil from the bucket cylinder 9 and return it to the tank. This allows the control valve 17F to drive the bucket cylinder 9 in response to the pilot pressure supplied from the operating device 26 or the hydraulic control valve 31.

[0048] <Operation system> As shown in FIG. 2, the operating system of the shovel 100 according to this embodiment includes a pilot pump 15, an operating device 26, a hydraulic control valve 31, a shuttle valve 32, and a hydraulic control valve 33.

[0049] The pilot pump 15 supplies pilot pressure to various hydraulic devices via a pilot line 25. The pilot pump 15 is mounted on the rear of the upper rotating body 3, for example, similar to the engine 11. The pilot pump 15 is, for example, a fixed displacement hydraulic pump, and is driven by the engine 11 as described above.

[0050] The pilot pump 15 may be omitted. In this case, the relatively high pressure hydraulic oil discharged from the main pump 14 is reduced in pressure by a predetermined pressure reducing valve, and the resulting relatively low pressure hydraulic oil is supplied to various hydraulic devices as pilot pressure.

[0051] The operation device 26 is provided near the cockpit of the cabin 10, and is used by the operator to operate various driven elements (lower traveling body 1, upper rotating body 3, boom 4, arm 5, bucket 6, etc.). In other words, the operation device 26 is used by the operator to operate hydraulic actuators (i.e., traveling hydraulic motors 1ML, 1MR, swing hydraulic motor 2A, boom cylinder 7, arm cylinder 8, bucket cylinder 9, etc.) that drive the respective driven elements. The operation device 26 includes, for example, lever devices that operate each of the boom 4 (boom cylinder 7), arm 5 (arm cylinder 8), bucket 6 (bucket cylinder 9), and upper rotating body 3 (swing hydraulic motor 2A). The operation device 26 also includes, for example, pedal devices or lever devices that operate each of the left and right crawlers (traveling hydraulic motors 1ML, 1MR) of the lower traveling body 1.

[0052] For example, as shown in FIG. 2, the operating device 26 is of a hydraulic pilot type. Specifically, the operating device 26 uses hydraulic oil supplied from the pilot pump 15 through a pilot line 25 and a pilot line 25A branched therefrom, and outputs a pilot pressure corresponding to the operation content to a secondary pilot line 27A. The pilot line 27A is connected to one inlet port of a shuttle valve 32, and is connected to the control valve 17 through a pilot line 27 connected to an outlet port of the shuttle valve 32. Thus, pilot pressure corresponding to the operation content related to various driven elements (hydraulic actuators) in the operating device 26 can be input to the control valve 17 through the shuttle valve 32. Therefore, the control valve 17 can drive each hydraulic actuator according to the operation content of the operating device 26 by an operator or the like.

[0053] The operating device 26 may be of an electric type. In this case, the operating device 26 outputs an electric signal (hereinafter, "operation signal") according to the operation content, and the operation signal is taken in by the controller 30. The controller 30 then outputs a control command according to the operation signal, that is, a control signal according to the operation content for the operating device 26, to the hydraulic control valve 31. As a result, a pilot pressure according to the operation content of the operating device 26 is input from the hydraulic control valve 31 to the control valve 17, and the control valve 17 can drive each hydraulic actuator according to the operation content of the operating device 26. In addition, the control valves 17A to 17F (directional control valves) built into the control valve 17 and driving each hydraulic actuator may be of an electromagnetic solenoid type. In this case, the operation signal output from the operating device 26 may be directly input to the control valve 17, that is, to each of the electromagnetic solenoid type control valves 17A to 17F.

[0054] The hydraulic control valve 31 is provided for each driven element (hydraulic actuator) to be operated by the operating device 26. That is, the hydraulic control valve 31 is provided for each of the left crawler (traveling hydraulic motor 1ML), the right crawler (traveling hydraulic motor 1MR), the upper swing body 3 (swing hydraulic motor 2A), the boom 4 (boom cylinder 7), the arm 5 (arm cylinder 8), and the bucket 6 (bucket cylinder 9). The hydraulic control valve 31 may be provided, for example, in the pilot line 25B between the pilot pump 15 and the control valve 17, and configured to be changeable in its flow path area (i.e., a cross-sectional area through which the hydraulic oil can flow). This allows the hydraulic control valve 31 to output a predetermined pilot pressure to the secondary pilot line 27B by using the hydraulic oil of the pilot pump 15 supplied through the pilot line 25B. Therefore, as shown in FIG. 2, the hydraulic control valve 31 can indirectly apply a predetermined pilot pressure corresponding to a control signal from the controller 30 to the control valve 17 through the shuttle valve 32 between the pilot line 27B and the pilot line 27.

[0055] The controller 30 may, for example, control the hydraulic control valve 31 to realize the automatic driving function. Specifically, the controller 30 outputs a control signal corresponding to an operation command related to the automatic driving function to the hydraulic control valve 31, regardless of whether the operating device 26 is operated or not. In this way, the controller 30 causes the hydraulic control valve 31 to supply a pilot pressure corresponding to the operation command related to the automatic driving function to the control valve 17, thereby realizing the operation of the excavator 100 based on the automatic driving function.

[0056] Furthermore, the controller 30 may, for example, control the hydraulic control valve 31 to realize remote operation of the shovel 100. Specifically, the controller 30 outputs a control signal corresponding to the content of remote operation specified by a remote operation signal received from an external device via the communication device 60 to the hydraulic control valve 31. As a result, the controller 30 can supply a pilot pressure corresponding to the content of the remote operation from the hydraulic control valve 31 to the control valve 17, thereby realizing the operation of the shovel 100 based on the remote operation by the operator.

[0057] As described above, when the electric operating device 26 is employed, the shuttle valve 32 described below is omitted. Therefore, the hydraulic control valve 31 can directly apply a predetermined pilot pressure corresponding to a control signal from the controller 30 to the control valve 17 through the pilot line 27B and the pilot line 27. Therefore, the controller 30 can supply a pilot pressure corresponding to the operation of the electric operating device 26 from the hydraulic control valve 31 to the control valve 17, thereby realizing the operation of the excavator 100 based on the operation of the operator.

[0058] 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. The shuttle valve 32 is provided for each driven element (hydraulic actuator) to be operated by the operation device 26. That is, the shuttle valve 32 is provided for each of the left crawler (travel hydraulic motor 1ML), the right crawler (travel hydraulic motor 1MR), the upper rotating body 3 (swing hydraulic motor 2A), the boom 4 (boom cylinder 7), the arm 5 (arm cylinder 8), and the bucket 6 (bucket cylinder 9). One of the two inlet ports of the shuttle valve 32 is connected to a pilot line 27A on the secondary side of the operation device 26 (specifically, the above-mentioned lever device or pedal device included in the operation device 26), and the other is connected to a pilot line 27B on the secondary side of the hydraulic control valve 31. The outlet port of the shuttle valve 32 is connected to the pilot port of the corresponding control valve of the control valve 17 through the pilot line 27. The corresponding control valve is a control valve that drives a hydraulic actuator that is the object of operation of the above-mentioned lever device or pedal device connected to one inlet port of the shuttle valve 32. Therefore, each of these shuttle valves 32 can apply the higher of the pilot pressure of the pilot line 27A on the secondary side of the operating device 26 and the pilot pressure of the pilot line 27B on the secondary side of the hydraulic control valve 31 to the pilot port of the corresponding control valve. In other words, the controller 30 can control the corresponding control valve regardless of the operation of the operating device 26 by the operator by outputting a pilot pressure higher than the pilot pressure on the secondary side of the operating device 26 from the hydraulic control valve 31. Therefore, the controller 30 can control the operation of the driven elements (the lower traveling body 1, the upper rotating body 3, and the attachment AT) regardless of the operating state of the operating device 26 by the operator, thereby realizing an automatic driving function.

[0059] The hydraulic control valve 33 is provided in the pilot line 27A that connects the operating device 26 and the shuttle valve 32. The hydraulic control valve 33 is configured to be able to change its flow path area, for example. The hydraulic control valve 33 operates in response to a control signal input from the controller 30. As a result, the controller 30 can forcibly reduce the pilot pressure output from the operating device 26 when the operating device 26 is operated by the operator. Therefore, even when the operating device 26 is being operated, the controller 30 can forcibly suppress or stop the operation of the hydraulic actuator corresponding to the operation of the operating device 26. In addition, for example, even when the operating device 26 is being operated, the controller 30 can reduce the pilot pressure output from the operating device 26 to make it lower than the pilot pressure output from the hydraulic control valve 31. Therefore, the controller 30 can reliably apply a desired pilot pressure to the pilot port of the control valve in the control valve 17, for example, regardless of the operation content of the operating device 26, by controlling the hydraulic control valve 31 and the hydraulic control valve 33. Therefore, the controller 30 can more appropriately realize the automatic operation function and remote control function of the shovel 100 by controlling the hydraulic control valve 33 in addition to the hydraulic control valve 31, for example.

[0060] Furthermore, if the shovel 100 is not equipped with a remote control function or an automatic operation function, the pilot line 27B, the hydraulic control valve 31, and the shuttle valve 32 may be omitted, and the pilot lines 27, 27A may be connected one-to-one and consolidated into a single pilot line.

[0061] <User interface> As shown in FIG. 2, the user interface system of the shovel 100 according to this embodiment includes an operation device 26, an output device 50, and an input device 52.

[0062] The output device 50 outputs various types of information to a user (operator) of the shovel 100 inside the cabin 10. The output device 50 includes a display device 50A and a sound output device 50B.

[0063] The display device 50A is provided at a location that is easily visible to an operator seated in the cabin 10, displays various information images, and outputs various information in a visual manner. The display device 50A is, for example, a liquid crystal display or an organic EL (Electroluminescence) display.

[0064] The output device 50 may include a lighting device capable of visually outputting various information, such as a warning light.

[0065] The sound output device 50B outputs various information by an auditory method, and includes, for example, a buzzer, an alarm, a speaker, and the like.

[0066] The output device 50 may include a device that outputs various information by a method other than a visual method or an auditory method, for example, a tactile method such as vibration of the cockpit.

[0067] The input device 52 is provided within a range close to an operator seated inside the cabin 10 and receives various inputs from the operator. Signals corresponding to the received inputs are taken into the controller 30.

[0068] For example, the input device 52 is an operation input device that accepts operation input. The operation input device may include a touch panel mounted on the display device 50A, a touch pad installed around the display device 50A, a button switch, a lever, a toggle, a knob switch provided on the operation device 26 (lever device), and the like.

[0069] Furthermore, for example, the input device 52 may be a voice input device that accepts voice input from an operator. The voice input device includes, for example, a microphone.

[0070] Furthermore, for example, the input device 52 may be a gesture input device that accepts a gesture input by an operator. The gesture input device includes, for example, an imaging device (an interior camera) installed in the cabin 10.

[0071] <Communications> As shown in FIG. 2, the communication system of the shovel 100 according to this embodiment includes a communication device 60.

[0072] The communication device 60 connects to a predetermined communication line and communicates with a device (e.g., a management device) provided separately from the shovel 100. The device provided separately from the shovel 100 may include a device outside the shovel 100, as well as a portable terminal device brought into the cabin 10 by the user of the shovel 100. The communication device 60 may be, for example, a 4G (4 th Generation) and 5G (5 th The communication device 60 may include a mobile communication module conforming to a standard such as IEEE 802.11 Generation. The communication device 60 may also include, for example, a satellite communication module. The communication device 60 may also include, for example, a WiFi communication module or a Bluetooth (registered trademark) communication module. The communication device 60 may also include, for example, a communication module capable of wired communication with a terminal device or the like connected via a cable connected to a predetermined connector.

[0073] <Control system> 2, the control system of the shovel 100 according to this embodiment includes a controller 30 and a storage device 47. The control system of the shovel 100 according to this embodiment also includes an operating pressure sensor 29, a boom angle sensor S1, an arm angle sensor S2, a bucket angle sensor S3, a machine attitude sensor S4, a swing angle sensor S5, and an imaging device S6.

[0074] The controller 30 (an example of a control device) performs various controls related to the shovel 100. The functions of the controller 30 may be realized by any hardware or any combination of hardware and software. For example, the controller 30 is configured mainly with a computer including a central processing unit (CPU), a memory device such as a random access memory (RAM), a non-volatile auxiliary storage device such as a read only memory (ROM), and various interface devices for input and output. The controller 30 realizes various functions by, for example, loading a program installed in the auxiliary storage device into the memory device and executing the program on the CPU.

[0075] The controller 30 performs control related to the operation of a hydraulic actuator (driven element) of the shovel 100, for example, with a hydraulic control valve 31 as a control object.

[0076] Specifically, the controller 30 may control the operation of a hydraulic actuator (driven element) of the shovel 100 based on the operation of the operating device 26, with the hydraulic control valve 31 as the control target.

[0077] Furthermore, the controller 30 may perform control related to remote operation of a hydraulic actuator (driven element) of the shovel 100, with the hydraulic control valve 31 as a control target. That is, the operation of the hydraulic actuator (driven element) of the shovel 100 may include remote operation of the hydraulic actuator from outside the shovel 100.

[0078] Furthermore, the controller 30 may control the automatic operation function of the shovel 100 by controlling the hydraulic control valve 31. That is, the operation of the hydraulic actuator of the shovel 100 may include an operation command for the hydraulic actuator of the shovel 100 that is output based on the automatic operation function.

[0079] Furthermore, the controller 30 performs control to prevent the shovel 100 from tipping forward (hereinafter, "anti-tip control"). The controller 30 includes, as functional units related to the anti-tip control, an attitude measurement unit 301, a soil volume estimation unit 302, a stability evaluation unit 303, and an anti-tip control unit 304. The functions of the attitude measurement unit 301, the soil volume estimation unit 302, the stability evaluation unit 303, and the anti-tip control unit 304 are realized, for example, by loading a program installed in an auxiliary storage device into a memory device and executing the program on a CPU.

[0080] 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.

[0081] Various data are stored in the storage device 47. The various data include data used in the processing of the controller 30. The various data may be stored in advance when the shovel 100 is shipped from a factory, or may be registered (stored) in the storage device 47 via the communication device 60 afterwards.

[0082] The storage device 47 stores, for example, survey data (an example of information related to the topography) of the work site of the shovel 100. The survey data is three-dimensional data that represents the topography of the work site of the shovel 100 before construction, and is generated, for example, based on the output of a drone equipped with a camera, a distance sensor (for example, LIDAR), or the like. The survey data is generated, for example, by a management device and received from the management device via the communication device 60 (an example of a first acquisition device).

[0083] Incidentally, some or all of the functions of the storage device 47 may be realized by an internal memory of the controller 30 (for example, an auxiliary storage device).

[0084] The operating pressure sensor 29 detects the pilot pressure on the secondary side (pilot line 27A) of the hydraulic pilot type operating device 26, i.e., the pilot pressure corresponding to the operating state of each driven element (hydraulic actuator) in the operating device 26. A detection signal of the pilot pressure by the operating pressure sensor 29, which corresponds to the operating state of the lower traveling body 1, upper rotating body 3, boom 4, arm 5, bucket 6, etc. in the operating device 26, is input to the controller 30.

[0085] When the electric operating device 26 is used, the operating pressure sensor 29 is omitted. In this case, the controller 30 can grasp the operating state of each driven element (hydraulic actuator) based on the operation signal received from the electric operating device 26.

[0086] The boom angle sensor S1 (an example of a second acquisition device) acquires detection information related to the attitude angle of the boom 4 (hereinafter, "boom angle") with respect to a predetermined reference (for example, a horizontal plane or a state at either end of the movable angle range of the boom 4, etc.). The boom angle sensor S1 may include, for example, a rotary encoder, an acceleration sensor, an angular velocity sensor, a six-axis sensor, an IMU (Inertial Measurement Unit), etc. The boom angle sensor S1 may also include a cylinder sensor capable of detecting the extension / retraction position of the boom cylinder 7.

[0087] The arm angle sensor S2 (an example of a second acquisition device) acquires detection information related to the attitude angle of the arm 5 (hereinafter, "arm angle") with respect to a predetermined reference (for example, a straight line connecting the connection points at both ends of the boom 4 or a state at either end of the movable angle range of the arm 5). The arm angle sensor S2 may include, for example, a rotary encoder, an acceleration sensor, an angular velocity sensor, a six-axis sensor, an IMU, etc. The arm angle sensor S2 may also include a cylinder sensor capable of detecting the extension / retraction position of the arm cylinder 8.

[0088] The bucket angle sensor S3 (an example of a second acquisition device) acquires detection information related to the attitude angle of the bucket 6 (hereinafter, "bucket angle") with respect to a predetermined reference (for example, a straight line connecting the connection points at both ends of the arm 5 or a state at either end of the movable angle range of the bucket 6). The bucket angle sensor S3 may include, for example, a rotary encoder, an acceleration sensor, an angular velocity sensor, a six-axis sensor, an IMU, etc. The bucket angle sensor S3 may also include a cylinder sensor capable of detecting the extension / retraction position of the bucket cylinder 9.

[0089] The vehicle attitude sensor S4 (an example of a second acquisition device) acquires detection information regarding the attitude state of the vehicle including the lower running body 1 and the upper rotating body 3. The attitude state of the vehicle includes the inclination state of the vehicle. The inclination state of the vehicle includes, for example, a tilt state in the front-rear direction corresponding to the attitude state about the left-right axis of the upper rotating body 3, and a tilt state in the left-right direction corresponding to the attitude state about the front-rear axis of the upper rotating body 3. The attitude state of the vehicle may also include a rotation state of the upper rotating body 3 corresponding to the attitude state about the rotation axis of the upper rotating body 3. The vehicle attitude sensor S4 is mounted on, for example, the upper rotating body 3, and acquires (outputs) detection data regarding the attitude angles about the front-rear axis and left-right axis of the upper rotating body 3 (hereinafter, "front-rear tilt angle" and "left-right tilt angle"). It may also acquire (output) detection data regarding the attitude angle about the rotation axis. This allows the vehicle attitude sensor S4 to acquire detection information regarding the orientation of the upper rotating body 3 with respect to the ground (rotation attitude around the rotation axis). The orientation of the upper rotating body 3 means, for example, the direction in which the attachment AT extends when viewed from above, that is, the forward direction as seen from the upper rotating body 3. The vehicle attitude sensor S4 may include, for example, an acceleration sensor (tilt sensor), an angular velocity sensor, a six-axis sensor, an IMU, etc.

[0090] The information on the orientation of the upper rotating body 3 with respect to the ground as a reference may be acquired from another device instead of or in addition to the aircraft attitude sensor S4. For example, a geomagnetic sensor may be mounted on the upper rotating body 3. In this case, the controller 30 can acquire information on the orientation of the upper rotating body 3 with respect to the ground as a reference from the geomagnetic sensor. Also, for example, the controller 30 may determine the orientation of the upper rotating body 3 with respect to the ground as a reference by determining the direction of the surrounding objects (particularly, fixed objects such as utility poles and trees) that are captured based on the output (captured image) of the imaging device S6. In other words, the information on the orientation of the upper rotating body 3 with respect to the ground as a reference may be acquired from the imaging device S6.

[0091] The swing angle sensor S5 acquires detection information on the relative swing angle of the upper swing body 3 with respect to the lower running body 1 as a reference. In this way, the swing angle sensor S5 acquires detection information on the swing angle of the upper swing body 3 with respect to, for example, a predetermined reference (for example, a state in which the forward direction of the lower running body 1 and the front of the upper swing body 3 coincide with each other). The swing angle sensor S5 includes, for example, a potentiometer, a rotary encoder, a resolver, etc.

[0092] For simplicity, it may be assumed that the orientation of the upper rotating body 3 with respect to the ground and the orientation of the upper rotating body 3 with respect to the lower traveling body 1 are substantially the same. In this case, the rotation angle sensor S5 may be omitted.

[0093] Furthermore, for example, the shovel 100 may further be equipped with a positioning device capable of measuring the absolute position of the shovel 100 itself. The positioning device is, for example, a Global Navigation Satellite System (GNSS) sensor. This can improve the estimation accuracy of the attitude state of the shovel 100. The GNSS sensor may also be used to obtain information regarding the orientation of the upper rotating body 3 with the ground as a reference. In this case, the controller 30 can obtain information regarding the orientation of the upper rotating body 3 with the ground as a reference from two or more GNSS sensors installed at different positions on the upper rotating body 3.

[0094] The imaging device S6 (an example of a first acquisition device) captures and outputs the captured image of the periphery of the shovel 100. The captured image output from the imaging device S6 is taken into the controller 30.

[0095] The imaging device S6 includes, for example, a monocular camera, a stereo camera, a depth camera, etc. Furthermore, the imaging device S6 may acquire three-dimensional data (for example, point cloud data or surface data) representing the positions and shapes of objects around the shovel 100 within a predetermined imaging range (angle of view) based on the captured image.

[0096] Furthermore, instead of or in addition to the imaging device S6, a distance sensor such as a LIDAR (Light Detecting and Ranging), a millimeter wave radar, an ultrasonic sensor, an infrared sensor, or a distance image sensor may be mounted on the shovel 100. The distance sensor may acquire three-dimensional data (e.g., point cloud data) that indicates the positions and shapes of objects around the shovel 100 within a predetermined detection range.

[0097] As shown in FIG. 1, the imaging device S6 is attached to, for example, the front end of the upper surface of the cabin 10, and acquires an image of the front of the upper rotating body 3 including the working range of the end attachment (bucket 6). This allows the controller 30 to recognize the situation in front of the shovel 100 based on the output of the imaging device S6. The controller 30 can also recognize the position of the shovel 100 and the rotation state of the upper rotating body 3 based on the positions and changes in appearance of objects around the shovel 100 recognized from the output (captured image) of the imaging device S6. The imaging range of the imaging device S6 includes the boom 4, the arm 5, and the end attachment (bucket 6), that is, the attachment AT. This allows the controller 30 to recognize the attitude state of the attachment (for example, at least one attitude angle of the boom 4, the arm 5, and the bucket 6) based on the output of the imaging device S6. Therefore, when the shovel 100 is remotely operated, the controller 30 transmits information on the surrounding image based on the imaging device S6 and various recognition results to an external device, and can provide an external operator with information on the shovel 100 (own machine) and its surrounding conditions. Also, when the shovel 100 operates with a fully automatic driving function, a control device (for example, the controller 30) related to the fully automatic driving function can output an operation command related to the hydraulic actuator while grasping the surrounding conditions of the shovel 100 and the attitude state of the own machine. Also, when the shovel 100 operates with a fully automatic driving function, the controller 30 transmits information on the surrounding image based on the imaging device S6 and various recognition results to an external device, and can provide a user (monitor) who monitors the work from the outside with information on the shovel 100 (own machine) and its surrounding conditions.

[0098] Furthermore, the imaging device S6 may be further configured to be capable of acquiring an image relating to at least one of the left, right, and rear of the upper rotating body 3. Specifically, the imaging device S6 may include at least one of a camera capable of imaging the left, right, and rear of the upper rotating body 3, in addition to a camera capable of imaging the front of the upper rotating body 3. This allows the controller 30 to recognize the situation not only in front of the shovel 100 (upper rotating body 3) but also to the left, right, and rear of the shovel 100 (upper rotating body 3).

[0099] In this example, the imaging device S6 and the distance sensor may be omitted.

[0100] The attitude measurement unit 301 measures the attitude of the machine body and attachment AT of the shovel 100. The attitude measurement unit 301 measures the attitude of the machine body and attachment AT of the shovel 100 in real time for each predetermined control period (hereinafter simply referred to as "control period"), for example, between the completion of the startup process of the controller 30 after the startup of the shovel 100 and the start of the termination process when the shovel 100 is stopped. "Real time" means that the attitude of the machine body and attachment AT is measured during a target control period based on the latest outputs of the boom angle sensor S1, arm angle sensor S2, bucket angle sensor S3, and machine body attitude sensor S4 at the start of that control period.

[0101] The attitude measurement unit 301 measures (calculates) the attitude angle of the boom 4 based on, for example, the output of the boom angle sensor S1. Similarly, the attitude measurement unit 301 measures (calculates) the attitude angle of the arm 5 based on, for example, the output of the arm angle sensor S2. Similarly, the attitude measurement unit 301 measures (calculates) the attitude angle of the bucket 6 based on, for example, the output of the bucket angle sensor S3. In addition, the attitude measurement unit 301 measures (calculates) the attitude angles (front-rear tilt angle, left-right tilt angle, and rotation angle) of the upper rotating body 3 based on, for example, the output of the machine body attitude sensor S4.

[0102] The soil volume estimation unit 302 estimates the volume of soil that acts as a load on the bucket 6 from above when the shovel 100 is excavating. The soil volume estimation unit 302 estimates the volume of soil that acts as a load on the bucket 6 from above in real time for each control cycle, for example, based on the attitude of the attachment AT of the shovel 100 and the machine body measured by the attitude measurement unit 301. "Real time" means that the volume of soil is estimated during a target control cycle based on the measurement results of the attitude measurement unit 301 in that control cycle. Details will be described later (see FIG. 3).

[0103] The stability evaluation unit 303 evaluates (estimates) the stability of the attitude of the shovel 100. For example, the stability evaluation unit 303 evaluates the stability of the attitude of the shovel 100 in real time for each control cycle, based on the attitude of the attachment AT and the machine body of the shovel 100 measured by the attitude measurement unit 301 and the volume of soil estimated by the soil volume estimation unit 302. "Real time" means that the stability of the shovel 100 is evaluated during a target control cycle based on the measurement results of the attitude measurement unit 301 and the estimation results of the soil volume estimation unit 302.

[0104] The stability of the posture of the shovel 100 is an index representing the difficulty of the shovel 100 to transition to a predetermined unstable state. Specifically, it is an index representing the difficulty of the shovel 100 toppling over. For example, when the possibility of the shovel 100 toppling over is relatively low, the stability evaluation unit 303 may determine (evaluate) that the stability of the posture of the shovel 100 is relatively high and that the posture of the shovel 100 is in a stable state. On the other hand, when the possibility of the shovel 100 toppling over is relatively high, the stability evaluation unit 303 may determine (evaluate) that the stability of the posture of the shovel 100 is relatively low and that the posture of the shovel 100 is in an unstable state. In addition, when the stability of the shovel 100 is decreasing at a relatively high speed, the stability evaluation unit 303 may determine (evaluate) that the posture of the shovel 100 is likely to transition to an unstable state and that the posture of the shovel 100 is likely to transition to an unstable state. Details of the stability evaluation method will be described later (see FIG. 3 and FIG. 4).

[0105] The overturn prevention control unit 304 performs control (overturn prevention control) for preventing overturning of the shovel 100, based on the evaluation result of the stability of the posture of the shovel 100 by the stability evaluation unit 303. Specifically, the overturn prevention control unit 304 may perform overturn prevention control when the stability evaluation unit 303 evaluates that the posture of the shovel 100 is in an unstable state or that there is a high possibility of it transitioning to an unstable state.

[0106] The overturn prevention control unit 304 may, for example, use the output device 50 to warn the operator that there is a possibility that the shovel 100 may overturn. Specifically, the overturn prevention control unit 304 may output a control command to the display device 50A to cause the display device 50A to display image information (for example, text information or a specific icon image, etc.) representing a warning that the shovel 100 may overturn. The overturn prevention control unit 304 may also output a control command to the sound output device 50B to cause the sound output device 50B to output a warning sound or audio information representing the possibility that the shovel 100 may overturn. In this way, the controller 30 can warn the operator that there is a possibility that the shovel 100 may overturn, and urge the operator to stop operating the attachment AT of the shovel 100.

[0107] Furthermore, when the shovel 100 is remotely operated or remotely monitored, the overturn prevention control unit 304 may transmit, for example, a signal to an external device (for example, a management device, etc.) indicating that there is a possibility that the shovel 100 may overturn. This allows the controller 30 to warn an operator or a supervisor of the possibility that the shovel 100 may overturn, via a display device or a sound output device in the external device. Therefore, the controller 30 can urge the remotely operated operator to stop the shovel 100, or urge the remotely monitored supervisor to perform an emergency stop operation for the shovel 100.

[0108] Furthermore, the tip-over prevention control unit 304 may restrict the operation of the attachment AT of the excavator 100, for example, by using the hydraulic control valve 31. Restrictions on the operation of the attachment AT include a control mode in which the attachment AT is not operated in response to the operation of the attachment AT, that is, the attachment AT is forcibly stopped. Restrictions on the operation of the attachment AT also include a control mode in which the operating speed of the attachment AT is reduced relatively in response to the operation of the attachment AT.

[0109] In addition, the anti-tip-over control unit 304 may change the manner (specifications) of the anti-tip-over control depending on whether the stability evaluation unit 303 evaluates that the shovel 100 is in an unstable state or whether it evaluates that there is a possibility that the shovel 100 will transition to an unstable state.

[0110] For example, when the stability evaluation unit 303 evaluates that there is a possibility that the shovel 100 will transition to an unstable state, the overturn prevention control unit 304 may only issue a warning to the operator or restrict the operation of the attachment AT. This allows the controller 30 to alert the operator that the posture of the shovel 100 is not unstable but is in a state where there is a high possibility that the shovel 100 will transition to an unstable state. On the other hand, when the stability evaluation unit 303 evaluates that the shovel 100 is in an unstable state, the overturn prevention control unit 304 may restrict the operation of the attachment AT instead of or in addition to issuing a warning to the operator. This allows the controller 30 to forcibly restrict the operation of the attachment AT when the posture of the shovel 100 is unstable, thereby increasing the possibility of preventing the shovel 100 from tipping forward.

[0111] Also, for example, when the stability evaluation unit 303 evaluates that there is a possibility that the shovel 100 will transition to an unstable state, the tip-over prevention control unit 304 may slow down the movement of the attachment AT in response to the operation of the attachment AT. This allows the controller 30 to suppress the posture of the shovel 100 from transitioning to an unstable state while minimizing the decrease in the work efficiency of the shovel 100. On the other hand, when the stability evaluation unit 303 evaluates that there is a possibility that the shovel 100 will transition to an unstable state, the tip-over prevention control unit 304 may stop the operation of the attachment AT regardless of whether or not the attachment AT is being operated. This allows the controller 30 to forcibly restrict the movement of the attachment AT in a situation where the posture of the shovel 100 has transitioned to an unstable state, thereby increasing the possibility of preventing the shovel 100 from tipping forward.

[0112] When the operation of the attachment AT is stopped, the tip-over prevention control unit 304 may permit the attachment AT to move in a direction that relatively increases the stability of the posture of the shovel 100. This allows an operator or the like to operate the attachment AT so as to return the posture of the shovel 100 from an unstable state to a stable state.

[0113] Furthermore, the overturn prevention control unit 304 may release (stop) the overturn prevention control when a predetermined operation for releasing the overturn prevention control (a warning to an operator or a restriction on the operation of the shovel 100) is performed through the input device 52. The overturn prevention control unit 304 may release (stop) the overturn prevention control when the stability evaluation unit 303 evaluates that the unstable state of the posture of the shovel 100 is resolved and that the posture of the shovel 100 is in a stable state.

[0114] [An example of a method for evaluating the stability of a shovel's posture] Next, an example of a method for evaluating the stability of the posture of the shovel 100 will be described with reference to Fig. 3. In this example, the stability evaluation unit 303 evaluates the stability of the posture of the shovel 100 based on the possibility of the shovel 100 tipping over due to a load (gravity) statically acting on the shovel 100.

[0115] Fig. 3 is a diagram for explaining an example of a method for evaluating the stability of the posture of the shovel 100. Specifically, Fig. 3 is a diagram showing the operation of lifting earth and sand by the attachment AT during the excavation process of the shovel 100.

[0116] As shown in FIGS. 3(a) and 3(b), when the shovel 100 uses the bucket 6 to lift up soil in the latter half of the excavation process, a load F corresponding to the weight of the soil on the bucket 6 is applied. s acts on the bucket 6. Therefore, when the excavator 100 lifts the bucket 6, a load F of soil and sand is applied from above to the bucket 6. s The moment (hereinafter, "tipping assist moment") M acts in a direction that tips the shovel 100 forward based on the front end (tipping fulcrum FL) of the ground contact portion of the lower running body 1 of the shovel 100. s The tipping-promoting moment M s is the tipping support FL and the load of soil F s The horizontal distance L between the point of action of the bucket 6 s , and the load F s (M s =F s L s ).

[0117] The controller 30 (stability evaluation unit 303) multiplies the volume of the soil estimated by the soil volume estimation unit 302 by the density of the soil to obtain the load F s The information on the density of the soil at the work site may be received from the management device via the communication device 60, for example, and stored in the storage device 47. In this way, the stability evaluation unit 303 can obtain (calculate) the load F s can be obtained (calculated).

[0118] As shown in Fig. 3(a), the sediment volume estimation unit 302 may estimate the volume of sediment located directly above the bucket 6. Also, as shown in Fig. 3(b), the sediment volume estimation unit 302 may estimate the volume of sediment located in the moving direction of the bucket 6 (indicated by the white arrow pointing diagonally upward to the left in the figure). The same may be true for other examples described below.

[0119] Specifically, first, the soil volume estimation unit 302 may acquire (calculate) position information of the bucket 6 based on the measurement results of the attitude measurement unit 301 and information on the specifications of the boom 4, the arm 5, and the bucket 6. The information on the specifications of the boom 4, the arm 5, and the bucket 6 is registered (stored) in advance in, for example, the storage device 47. The information on the specifications of the boom 4, the arm 5, and the bucket 6 includes, for example, the center distance between the base end and the tip of the boom 4, the center distance between the base end and the tip of the arm 5, information on the shape of the bucket 6, etc.

[0120] The soil volume estimation unit 302 may grasp the shape (topography) of the ground in front of the shovel 100 based on the survey data in the storage device 47, and estimate the volume of soil to be loaded from above the shovel 100 based on the relationship between the acquired position information of the bucket 6 and the topography. .Ma Furthermore, when taking into consideration the moving direction of the bucket 6, the soil volume estimation unit 302 may acquire (calculate) the moving direction of the bucket 6 based on the position information of the bucket 6 in the current control cycle and the position information of the bucket 6 in the previous control cycle. This allows the soil volume estimation unit 302 to estimate the volume of soil located in the moving direction of the bucket 6.

[0121] The stability evaluation unit 303 may also acquire position information of the bucket 6 relative to the machine body based on the intermediate calculation results of the soil volume estimation unit 302. s It is possible to obtain position information of the point of action relative to the bucket 6.

[0122] The stability evaluation unit 303 may grasp the orientation of the lower running body 1 relative to the upper rotating body 3 based on the output of the vehicle attitude sensor S4 or the turning angle sensor S5, and information on the specifications of the lower running body 1, and obtain (calculate) position information of the front end (tipping support FL) of the ground contact portion of the lower running body 1. Information on the specifications of the lower running body 1 is stored in advance in, for example, the storage device 47. Information on the specifications of the lower running body 1 includes, for example, information on various dimensions between the turning center and the outer edge of the ground contact portion when the lower running body 1 is viewed from above. In this way, the stability evaluation unit 303 can determine the position of the tipping support FL and the load of soil and sand F. s The horizontal distance L between the point of action of the bucket 6 s Therefore, the stability evaluation unit 303 can obtain (calculate) the load F s and distance L s Based on the calculation result, the tipping promotion moment M s can be obtained (calculated).

[0123] On the other hand, the center of gravity G of the shovel 100 is located behind the front end (tipping fulcrum FL) of the ground contact portion of the lower running structure 1 of the shovel 100. exc is the moment M in the direction that prevents the excavator 100 from tipping forward. exc (hereinafter, the "overturning suppression moment") is applied to the excavator 100. The overturning suppression moment M exc is the horizontal distance L between the tipping fulcrum FL and the center of gravity G. exc , and a load F equivalent to the weight of the shovel 100 exc (M exc =F exc L exc ).

[0124] The stability evaluation unit 303 may acquire (calculate) the position of the center of gravity of each of the machine body, the boom 4, the arm 5, and the bucket 6 based on the attitude of each of them measured by the attitude measurement unit 301. Then, the stability evaluation unit 303 may acquire position information of the center of gravity G of the shovel 100 based on the weight and center of gravity position of each of the machine body, the boom 4, the arm 5, and the bucket 6. Information regarding the weight of the shovel 100 is registered (stored) in advance in the storage device 47, for example. Thereby, the horizontal distance L between the position of the tipping fulcrum FL and the center of gravity G can be calculated using the position information of the tipping fulcrum FL and the center of gravity G. exc Therefore, the stability evaluation unit 303 can obtain (calculate) the load F corresponding to the weight of the shovel 100. exc , and distance L exc Based on the calculation result, the fall prevention moment M exc can be obtained (calculated).

[0125] The stability evaluation unit 303 calculates the tipping-promoting moment M s and the fall prevention moment M exc The stability of the excavator 100 is evaluated based on the relationship between the

[0126] The stability evaluation unit 303 evaluates, for example, the fall prevention moment M exc is the tipping assist moment M s If it is greater than 1, that is, if the following formula (1) is established, it is evaluated that the shovel 100 is in a stable state.

[0127]

number

[0128] On the other hand, the stability evaluation unit 303, for example, calculates the fall prevention moment M exc is the tipping assist moment M s If the above is true, that is, if the following formula (2) is established, the shovel 100 is evaluated to be in an unstable state.

[0129]

number

[0130] In addition, for example, when the posture of the shovel 100 is stable and the stability of the posture of the shovel 100 is decreasing at a relatively high rate, that is, when the above-mentioned formula (1) and the following formula (3) using a predetermined threshold value Th (<0) are satisfied, the stability evaluation unit 303 may evaluate that there is a high possibility that the shovel 100 will transition to an unstable state.

[0131]

number

[0132] Thus, in this example, the controller 30 estimates the volume of soil that the attachment AT lifts using the bucket 6, and evaluates the stability of the attitude of the vehicle body including the lower running body 1 and the upper rotating body 3 based on the estimated volume of soil.

[0133] This allows the controller 30 to evaluate the stability of the posture of the shovel 100 even before the machine body actually tilts. Therefore, the controller 30 can grasp the unstable state of the shovel 100, for example, before the rear part of the undercarriage 1 of the shovel 100 lifts up, and can perform anti-tipping control of the shovel 100 in advance.

[0134] In this example, the controller 30 estimates the volume of earth and sand to be loaded onto the bucket 6 from above, based on the outputs of the sensors S1 to S4 and survey data acquired (taken in) from the outside by the communication device 60.

[0135] This enables the controller 30 to specifically estimate the volume of soil and sand that will be loaded onto the bucket 6 from above.

[0136] Moreover, in this example, the controller 30 estimates the volume of soil to be loaded from above the bucket 6 based on the moving direction of the bucket 6.

[0137] This enables the controller 30 to more appropriately estimate the volume of soil and sand onto which the load is applied from above the bucket 6.

[0138] [Another example of how to evaluate the stability of a shovel's posture] Next, another example of the method for evaluating the stability of the shovel 100 will be described with reference to Fig. 4. In this example, the stability evaluation unit 303 evaluates the stability of the posture of the shovel 100 based on the possibility of the shovel 100 tipping over, taking into account both the load acting statically on the shovel 100 (gravity) and the load acting dynamically on the shovel 100 (inertia force).

[0139] Fig. 4 is a diagram for explaining another example of a method for evaluating the stability of the posture of the shovel 100. Specifically, Fig. 4(a) is a diagram showing an example of a zero moment point (ZMP) of the shovel 100. Also, Fig. 4(b) is a diagram showing an example of gravity and inertial forces acting on the shovel 100 when the attachment AT lifts up earth and sand in the excavation process of the shovel 100.

[0140] In this example, the zero moment point is treated on an xyz coordinate system in which the intersection of the rotation axis of the upper rotating body 3 of the shovel 100 and the ground is set as the origin, and the front-to-rear axis, left-to-right axis, and rotation axis of the upper rotating body 3 are set as the x-axis, y-axis, and z-axis, respectively.

[0141] In this example, the controller 30 (stability evaluation unit 303) calculates the zero moment point of the shovel 100, and evaluates the stability of the posture of the shovel 100 based on the calculated zero moment point. The zero moment point refers to a point where the direction of the resultant force of gravity and inertia force acting on the shovel 100 intersects with the ground.

[0142] As shown in Fig. 4(a), when the zero moment point (point 401 in the figure) is within the range of the ground contact area 402 of the lower traveling body 1, the shovel 100 will not tip over due to the moment caused by the resultant force of gravity and inertia acting on the shovel 100. On the other hand, when the zero moment point is outside the ground contact area 402, the shovel 100 may tip over due to the moment caused by the resultant force of gravity and inertia acting on the shovel 100. The ground contact area 402 is a substantially rectangular area defined by both end positions in the width direction of the lower traveling body 1, specifically, the left end position of the left crawler 1C and the right end position of the right crawler 1C, and both end positions of the ground contact portion in the traveling direction of the lower traveling body 1.

[0143] As shown in FIG. 4(b), the forces acting on the excavator 100 (gravity and inertia) are approximated by mass point approximation using the forces acting on the lower traveling body 1, the upper rotating body 3, the boom 4, the arm 5, the bucket 6, and the soil that applies a load to the bucket 6 from above. The stability evaluation unit 303 applies mass point approximation and calculates the x and y coordinates (x ZMP ,y ZMP ) can be calculated.

[0144]

number

[0145] The subscript i is an integer from 0 to 5, and each value corresponds to the lower traveling structure 1, the upper rotating structure 3, the boom 4, the arm 5, the bucket 6, and the soil that applies a load to the bucket 6 from above, respectively.

[0146] Information on the position and mass of the mass point (center of gravity) in each of the configurations of the lower traveling body 1, the upper rotating body 3, the boom 4, the arm 5, and the bucket 6 is registered (stored) in advance in, for example, the storage device 47. Since the upper rotating body 3 is assumed not to rotate during excavation, the mass points of the lower traveling body 1 and the upper rotating body 3 are uniquely determined based on the relative rotation angle between the lower traveling body 1 and the upper rotating body 3 measured by the attitude measurement unit 301. Since the acceleration of the lower traveling body 1 and the upper rotating body 3 is assumed to be zero during excavation. The positions of the mass points of the boom 4, the arm 5, and the bucket 6 relative to the machine body are acquired (calculated) based on the measurement results of the attitude measurement unit 301. The acceleration of the mass points of the boom 4, the arm 5, and the bucket 6 is acquired (calculated) based on, for example, the outputs of the acceleration sensor, the angular velocity sensor, the IMU, the six-axis sensor, and the like included in each of the sensors S1 to S3. Moreover, the mass of the soil that applies a load to the bucket 6 from above is acquired (calculated) based on the estimation result of the soil volume estimation unit 302, as in the above example. Moreover, the mass point of the soil that applies a load to the bucket 6 from above may be acquired by, for example, calculating a geometric centroid under the assumption that the density of the soil is constant. Moreover, the acceleration of the mass point of the soil that applies a load to the bucket 6 from above may be considered to be equivalent to the acceleration of the bucket 6. In this way, the stability evaluation unit 303 can acquire (calculate) the zero moment point of the excavator 100 using equation (4).

[0147] For example, when the zero moment point is within the ground contact area, the stability evaluation unit 303 evaluates (determines) that the possibility of the shovel 100 tipping forward is low and the attitude of the shovel 100 is stable.

[0148] On the other hand, for example, if the zero moment point is outside the installation area, the stability evaluation unit 303 evaluates (determines) that there is a high possibility that the shovel 100 will tip over forward and that the posture of the shovel 100 is unstable.

[0149] Also, as in the example described above, the stability evaluation unit 303 may evaluate that there is a high possibility that the posture of the shovel 100 will transition to an unstable state, for example, when the speed moving outside the ground contact area of ​​the zero moment point is relatively high (specifically, greater than or equal to a predetermined threshold value).

[0150] Thus, in this example, as in the first example described above, the controller 30 estimates the volume of soil that the attachment AT lifts using the bucket 6, and evaluates the stability of the attitude of the vehicle body including the lower running body 1 and the upper rotating body 3 based on the estimated volume of soil.

[0151] This allows the controller 30 to evaluate the stability of the posture of the shovel 100 even before the machine body actually tilts, as in the case of the above example. Therefore, the controller 30 can grasp the unstable state of the shovel 100, for example, before the rear part of the undercarriage 1 of the shovel 100 lifts up, and can perform anti-tipping control of the shovel 100 in advance.

[0152] Also, in this example, the controller 30 evaluates the stability of the posture of the body of the shovel 100 based on the acceleration of the boom 4, the arm 5, the bucket 6, and the soil that acts as a load on the bucket 6 from above.

[0153] This enables the controller 30 to evaluate the stability of the dynamic posture of the shovel 100's body by taking into account not only the gravity acting on the shovel 100 but also the inertial force acting on the shovel 100 due to the operation of the attachment AT.

[0154] The controller 30 (stability evaluation unit 303) may evaluate the stability of the attitude of the body of the shovel 100 by combining the evaluation method of the above example and this example.

[0155] [Other examples of excavator configurations] Next, another example of the configuration of the shovel 100 according to this embodiment will be described with reference to FIG.

[0156] 5 is a block diagram showing another example of the configuration of the shovel 100 according to this embodiment. The following will mainly explain the differences from the above example (FIG. 2).

[0157] The shovel 100 of this example differs from the above-mentioned example in that at least one of the imaging device S6 and the distance sensor is an essential component, and in that the survey data in the storage device 47 is omitted.

[0158] In this example, unlike the above example, the controller 30 (soil volume estimation unit 302) grasps the topography around the shovel 100 based on the output (one example of information related to the topography) of at least one of the imaging device S6 and the distance sensor instead of the survey data. This allows the soil volume estimation unit 302 to estimate the volume of soil that applies a load to the bucket 6 from above, based on the topography ahead of the shovel 100 and position information of the bucket 6 grasped from the output of the imaging device S6 and the distance sensor.

[0159] In this example, the stability evaluation unit 303 may employ any one of the example (FIG. 3) and other examples (FIG. 4) of the above-mentioned evaluation method to evaluate the stability of the attitude of the body of the shovel 100. Furthermore, the stability evaluation unit 303 may evaluate the stability of the attitude of the body of the shovel 100 by combining the example and other examples of the above-mentioned evaluation method.

[0160] Thus, in this example, the controller 30 estimates the volume of soil to be loaded onto the bucket 6 from above based on the outputs of the sensors S1 to S4 and the output of the imaging device S6 that images the area around the shovel 100, or the output of a distance sensor that measures the distance to objects around the shovel 100.

[0161] This enables the controller 30 to specifically estimate the volume of soil and sand that will be loaded onto the bucket 6 from above.

[0162] Although the embodiments have been described in detail above, the present disclosure is not limited to such specific embodiments, and various modifications and variations are possible within the scope of the gist described in the claims. [Explanation of symbols]

[0163] 1 Undercarriage 1C Crawler 1ML, 1MR Travel hydraulic motor 2A hydraulic slewing motor 3. Upper rotating body 4. Boom 5 Arm 6 Bucket 7 Boom cylinder 8 Arm Cylinder 9 Bucket Cylinder 11 Engine 14 Main pump 17 Control valve 30 Controller (control device) 50 Output Device 50A display device 50B Sound output device 52 Input Device 60 Communication device (first acquisition device) 100 Shovel AT attachment (work attachment) S1 Boom angle sensor (second acquisition device) S2 Arm angle sensor (second acquisition device) S3 Bucket angle sensor (second acquisition device) S4 Aircraft attitude sensor (second acquisition device) S5 Rotation Angle Sensor S6 Imaging device (first acquisition device)

Claims

1. A lower running body; An upper rotating body rotatably mounted on the lower traveling body; A work attachment attached to the upper rotating body and including a boom, an arm, and a bucket; a control device that estimates a volume of soil to be lifted by the work attachment using the bucket, and evaluates the stability of an attitude of a machine body including the lower traveling body and the upper rotating body based on the estimated volume of soil, The stability of the attitude of the aircraft is an index representing the resistance of the aircraft to tipping over. Shovel.

2. A first acquisition device that acquires information regarding the topography around the shovel; a second acquisition device that acquires information regarding the posture of the work attachment, The control device estimates the volume of the soil based on information about the topography and information about the attitude of the work attachment. The shovel according to claim 1.

3. The control device evaluates the stability of the attitude of the vehicle based on the acceleration of the boom, the arm, the bucket, and the soil that applies a load to the bucket. The shovel according to claim 1 or 2.

4. The control device estimates a volume of the soil that acts as a load on the bucket when the bucket is lifted from the ground based on a moving direction of the bucket during a lifting operation of the bucket. A shovel according to any one of claims 1 to 3.

5. The first acquisition device acquires survey data of a work site as information related to the topography from an external source. The shovel according to claim 2.

6. The first acquisition device is an imaging device that images the periphery of the shovel, or a distance sensor that measures the distance between the shovel and an object in the periphery of the shovel. The shovel according to claim 2.

Images