Automatic control system for work machines

Abstract

Provided is an automated control system for a work machine with which it is possible to prevent deterioration in the workability of automated work due to instability of ground for the work machine. The automated control system for the work machine comprises an automated traveling control unit 703 that performs automated traveling of the work machine, an automated work control unit (automated excavation control unit 704) that performs automated work of the work machine, and a stability determination unit 702 that determines the stability of ground for the work machine. In a case where the execution of automated traveling control with the automated traveling control unit 703 is followed by the execution of automated work control with the automated work control unit (automated excavation control unit 704), stability determination with the stability determination unit 702 is executed before the automated work control is executed, and the automated control of the work machine is executed on the basis of the determination result from the stability determination unit 702.

Description

[Technical Field]

[0001] The present invention relates to an automatic control system for a work machine. [Background technology]

[0002] 2. Description of the Related Art Generally, there are working machines such as hydraulic excavators that have a traveling body and an upper rotating body that is rotatably provided above the traveling body.

[0003] Patent Document 1 describes a technique for automating the work of such a work machine. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2020-020153 Summary of the Invention [Problem to be solved by the invention]

[0005] In Patent Document 1, for example, the excavation start position for a work device is determined based on topographical data indicating the topography measured by a topographical sensor that measures the topography, and the work device is moved from its current position to the excavation start position. Technology for automating work machines such as that disclosed in Patent Document 1 is premised on stable footing.

[0006] However, work machines such as excavators sometimes travel on uneven ground. For example, if you try to automate the operation of an excavator, including its travel, if the footing it travels to is unstable, the subsequent automated work will be unstable, which could affect workability.

[0007] The present invention has been made in view of the above-mentioned circumstances and aims to solve these problems, and has as its object to provide an automatic control system for a work machine that can suppress deterioration of the workability of automated work due to instability in the footing of the work machine. [Means for solving the problem]

[0008] In order to solve the above problems, the automatic control system for a work machine of the present invention is an automatic control system for a work machine comprising a work machine having a plurality of driven members driven by a plurality of actuators, and a control device that controls the work machine, wherein the control device comprises an automatic driving control unit that performs automatic driving of the work machine, an automatic work control unit that performs automatic work of the work machine, and a stability judgment unit that judges the stability of the scaffolding of the work machine, and is characterized in that when automatic work control is performed by the automatic driving control unit after automatic driving control is performed by the automatic work control unit, a stability judgment is performed by the stability judgment unit before performing the automatic work control, and automatic control of the work machine is performed based on the judgment result of the stability judgment unit. [Effects of the Invention]

[0009] The present invention can prevent automatic control from being initiated on unstable scaffolding, thereby preventing workability from being impaired.

[0010] Problems, configurations, and effects other than those described above will become apparent from the following description of the embodiments. [Brief explanation of the drawings]

[0011] [Figure 1] Diagram of a hydraulic excavator. [Figure 2] FIG. 2 is a diagram showing a controller for controlling a hydraulic excavator together with a hydraulic drive unit. [Figure 3] Detailed view of the solenoid valve unit. [Figure 4A] FIG. 2 is a side view showing a coordinate system in the hydraulic excavator of FIG. 1. [Figure 4B] FIG. 2 is a top view showing a coordinate system in the hydraulic excavator of FIG. 1. [Figure 5] FIG. 2 is a hardware configuration diagram of a controller according to the first embodiment. [Figure 6] FIG. 2 is a functional block diagram of a controller according to the first embodiment (during boarding operation); [Figure 7] FIG. 2 is a functional block diagram of a controller according to the first embodiment (in automatic control mode). [Figure 8] FIG. 4 is a diagram showing the relationship between the target control pressure and the operation signal of the electromagnetic proportional valve. [Figure 9] 7 is a control flowchart of an automatic control execution management unit 701 according to the first embodiment. [Figure 10] 7 is a control flowchart of a stability determination unit 702 in the first embodiment. [Figure 11] FIG. 3 is a diagram showing an example of operation of the first embodiment. [Figure 12] FIG. 10 is a diagram showing a first example of the measurement result of the vehicle body tilt angle φ when S500 of the first embodiment is executed. [Figure 13] FIG. 10 is a diagram showing a second example of the measurement result of the vehicle body tilt angle φ when S500 of the first embodiment is executed. [Figure 14] FIG. 10 is a functional block diagram of a controller according to a second embodiment (in automatic control mode). [Figure 15] 10 is a control flowchart of a stability determination unit 702 according to the second embodiment. [Figure 16] FIG. 10 is a diagram showing an operation example of the second embodiment. [Figure 17] FIG. 10 is a diagram showing an example of the measurement result of Zl when S501 of the second embodiment is executed. [Figure 18] FIG. 10 is a diagram showing a controller for a hydraulic excavator according to a third embodiment together with a hydraulic drive system. [Figure 19] FIG. 10 is a detailed view of a solenoid valve unit according to a third embodiment. [Figure 20] FIG. 10 is a functional block diagram of a controller according to a third embodiment (in automatic control mode). [Figure 21] 10 is a control flowchart of a stability determination unit 702 according to the third embodiment. [Figure 22] 10 is a control flowchart of a stability determination unit 702 according to the fourth embodiment. [Figure 23] 10 is a diagram showing an example of measurement results of a vehicle body tilt angle φ, used to explain a first modification of the stability determination method. FIG. [Figure 24] 10 is a diagram showing an example of measurement results of angle φr (vehicle body tilt angle φ−vehicle body tilt angle φ0 at the time of executing the determination operation) provided for explaining Modification 2 of the stability determination method. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In each drawing, parts having the same function are given the same reference numerals, and repeated description may be omitted. Note that, although the following describes an example of a hydraulic excavator equipped with a bucket 10 as a working implement (attachment) at the tip of a working device, the present invention can also be applied to hydraulic excavators equipped with working implements other than buckets, and to work machines other than hydraulic excavators.

[0013] In the following explanation of this paper, when there are multiple identical components, an alphabet may be added to the end of the reference number (number), but the alphabet may be omitted to refer to the multiple components collectively. For example, when there are two pumps 2a and 2b, they may be collectively referred to as pump 2.

[0014] [First embodiment] <Basic configuration> FIG. 1 is a configuration diagram of a hydraulic excavator according to a first embodiment of the present invention, FIG. 2 is a diagram showing a controller for the hydraulic excavator according to the first embodiment of the present invention together with a hydraulic drive system, and FIG. 3 is a detailed diagram of a solenoid valve unit 160 in FIG. 2.

[0015] 1, the hydraulic excavator 1 is made up of an articulated front working implement 1A and a vehicle body 1B. The vehicle body 1B comprises a lower traveling body 11 that travels using left and right traveling hydraulic motors 3a (FIGS. 2 and 3), 3b (right traveling hydraulic motor 3a, left traveling hydraulic motor 3b), and an upper rotating body 12 that is attached to the lower traveling body 11 and rotates using a swing hydraulic motor 4.

[0016] The front working mechanism 1A is configured by connecting a plurality of driven members (a boom 8, an arm 9, and a bucket 10) that each rotate in the vertical direction. The base end of the boom 8 is rotatably supported via a boom pin at the front of the upper rotating body 12. An arm 9 is rotatably connected to the tip of the boom 8 via an arm pin, and a bucket 10 is rotatably connected to the tip of the arm 9 via a bucket pin. The boom 8 is driven by a boom cylinder 5, the arm 9 is driven by an arm cylinder 6, and the bucket 10 is driven by a bucket cylinder 7.

[0017] A boom angle sensor 30 is attached to the boom pin, an arm angle sensor 31 to the arm pin, and a bucket angle sensor 32 to the bucket link 13 so that the rotation angles α, β, and γ (see FIG. 4A) of the boom 8, arm 9, and bucket 10 can be measured, and a vehicle body inclination angle sensor 33 is attached to the upper rotating body 12 to detect the inclination angle φ (see FIG. 4A) of the upper rotating body 12 (vehicle body 1B) relative to a reference plane (e.g., a horizontal plane). Note that angle sensors 30, 31, and 32 can each be replaced with an angle sensor relative to a reference plane (e.g., a horizontal plane).

[0018] A swing angle sensor 34 is attached to the swing center axis (also referred to as the swing axis) so that the relative angle θ (see FIGS. 4A and 4B) between the upper swing body 12 and the lower travel body 11 can be measured.

[0019] Installed within the operator's cab 120 provided in the upper rotating body 12 are a right travel lever 23a for operating the right travel hydraulic motor 3a (lower traveling body 11), a left travel lever 23b for operating the left travel hydraulic motor 3b (lower traveling body 11), a right operating lever 22a for operating the boom cylinder 5 (boom 8) and the bucket cylinder 7 (bucket 10), and a left operating lever 22b for operating the arm cylinder 6 (arm 9) and the swing hydraulic motor 4 (upper rotating body 12). Hereinafter, the right travel lever 23a, the left travel lever 23b, the right operating lever 22a, and the left operating lever 22b may be collectively referred to as operating devices 22, 23.

[0020] An engine speed setting device 480 for setting the engine speed is also installed in the operator's cab 120.

[0021] As shown in FIG. 2, an engine 18, which is a prime mover mounted on the upper rotating body 12, drives hydraulic pumps 2a, 2b and a pilot pump 48. The hydraulic pumps 2a, 2b are variable displacement pumps whose displacements are controlled by regulators 2aa, 2ba, and the pilot pump 48 is a fixed displacement pump. The hydraulic pumps 2a, 2b and the pilot pump 48 draw hydraulic oil from a tank 200. In this embodiment, as shown in FIG. 2, a control signal output from a controller 40 is input to the regulators 2aa, 2ba. Although a detailed configuration of the regulators 2aa, 2ba is omitted, the discharge flow rates of the hydraulic pumps 2a, 2b are controlled in response to the control signal.

[0022] The pump line 130, which is the discharge pipe of the pilot pump 48, passes through the lock valve 39 and is then connected to each electromagnetic proportional valve in the solenoid valve unit 160. In this example, the lock valve 39 is a solenoid-operated directional control valve, and its electromagnetic driver is electrically connected to a position detector of a gate lock lever (not shown) located in the operator's cab 120 (FIG. 1). The position of the gate lock lever is detected by the position detector, and a signal corresponding to the position of the gate lock lever is input from the position detector to the lock valve 39. When the gate lock lever is in the locked position, the lock valve 39 closes and the pump line 130 is cut off, and when the gate lock lever is in the unlocked position, the lock valve 39 opens and the pump line 130 is open. In other words, when the pump line 130 is cut off, operation by the operating devices 22 and 23 is disabled, and operations such as traveling, swinging, and excavation are prohibited.

[0023] The operating devices 22, 23 are of an electric lever type, and generate an electric signal corresponding to the amount and direction of operation by the operator. The electric signal thus generated is input to the control controller 40, which then outputs an electric signal to the solenoid valve unit 160 to drive the solenoid proportional valves 50-55 (see FIG. 3) corresponding to the operation input to the operating devices 22, 23. The solenoid proportional valves 50-55 supply the input electric signal to hydraulic actuators 150a-155b of the corresponding flow control valves 15a-15f via pilot lines 140a-145b, and the signal is used as a control signal to drive these flow control valves 15a-15f.

[0024] The pressure oil discharged from the hydraulic pump 2 is supplied via flow control valves 15a, 15b, 15c, 15d, 15e, and 15f to the right traveling hydraulic motor 3a, the left traveling hydraulic motor 3b, the swing hydraulic motor 4, the boom cylinder 5, the arm cylinder 6, and the bucket cylinder 7. The supplied pressure oil causes the boom cylinder 5, the arm cylinder 6, and the bucket cylinder 7 to extend and retract, thereby rotating the boom 8, the arm 9, and the bucket 10, respectively, changing the position and attitude of the bucket 10. The supplied pressure oil also rotates the swing hydraulic motor 4, causing the upper swing structure 12 to swing relative to the lower traveling structure 11. The supplied pressure oil then rotates the right traveling hydraulic motor 3a and the left traveling hydraulic motor 3b, causing the lower traveling structure 11 to travel.

[0025] Pressure sensors 16a to 16f and 16k to 16l are provided to the swing hydraulic motor 4, boom cylinder 5, arm cylinder 6, and bucket cylinder 7 so as to detect the actuator pressures. The pressure sensors 16a to 16f and 16k to 16l detect the pressures in the input and output lines of the swing hydraulic motor 4, and the pressures on the bottom and rod sides of the boom cylinder 5, arm cylinder 6, and bucket cylinder 7, respectively, and output them as electrical signals to the controller 40 (in FIG. 2, the connection lines from the pressure sensors 16a to 16f and 16k to 16l to the controller 40 are not shown due to space limitations).

[0026] Pressure sensors 16g to 16j are provided in the flow paths connecting the travel hydraulic motors 3a, 3b and the flow control valves 15e, 15f so that the actuator pressure of the travel hydraulic motors 3a, 3b can be detected. The pressure sensors 16g to 16j detect the pressure in the input / output lines of the travel hydraulic motors 3a, 3b, and output the result as an electric signal to the controller 40 (in FIG. 2, the connection lines from the pressure sensors 16g to 16j to the controller 40 are not shown due to space limitations).

[0027] The engine 18 is provided with an engine control controller 470 that controls the rotation speed and other parameters of the engine 18 in response to a control signal from the control controller 40. The engine 18 is provided with an engine rotation speed detection device 490, which is a rotation sensor for detecting the engine rotation speed.

[0028] <Solenoid valve unit 160> As shown in FIG. 3, the solenoid valve unit 160 has a primary port side connected to the pilot pump 48 via the pump line 130, and includes solenoid proportional valves 50a to 55b that reduce the pilot pressure from the pilot pump 48 and output it to pilot lines 140a to 145b.

[0029] The pilot lines 140a to 145b are provided with pressure sensors 17a to 17l so as to detect the output pressures of the electromagnetic proportional valves 50a to 55b.

[0030] The electromagnetic proportional valves 50a to 55b have a minimum opening when not energized, and the opening increases as the current, which is the control signal from the controller 40, increases. In this way, the opening of each of the electromagnetic proportional valves 50a to 55b corresponds to the control signal from the controller 40.

[0031] The electromagnetic proportional valves 54a and 55a drive the traveling hydraulic motor 3 in the direction in which the undercarriage 11 moves forward, and the electromagnetic proportional valves 54b and 55b drive the traveling hydraulic motor 3 in the direction in which the undercarriage 11 moves backward.

[0032] In the solenoid valve unit 160 configured as described above, when a control signal is output from the control controller 40 to drive the solenoid proportional valves 50a to 55b, pilot pressure can be generated even when the corresponding operating devices 22, 23 are not operated by an operator, so that the operation of each actuator (3 to 7) can be forcibly generated.

[0033] Here, the hydraulic excavator coordinate system set in the hydraulic excavator will be described. Figures 4A and 4B are diagrams for explaining the excavator coordinate system, with Figure 4A showing a side view and Figure 4B showing a top view.

[0034] 4A and 4B, in this embodiment, an excavator coordinate system is defined for the hydraulic excavator 1. The excavator coordinate system is an XYZ coordinate system fixed with respect to the lower traveling structure 11, and a vehicle body coordinate system is set having a Z axis that extends in a direction along the central axis of rotation of the upper rotating structure 12, passes through the center point of rotation, and has its positive direction pointing upward; an X axis that extends in a direction along the plane on which the front working implement 1A operates, perpendicular to the Z axis, passes through the base end of the boom, and has its positive direction pointing forward when the upper rotating structure 12 is in a position facing forward with respect to the lower traveling structure 11; and a Y axis that passes through the intersection of the Z axis and X axis, and has its positive direction pointing forward in the plane of the page in FIG. 4A so as to form a right-handed coordinate system.

[0035] Furthermore, the distance from the intersection of the X-axis and Z-axis (origin O) to the base end of the boom is defined as L0, the length of boom 8 (the linear distance between the connecting parts at both ends) as L1, the length of arm 9 (the linear distance between the connecting parts at both ends) as L2, and the length of bucket 10 (the linear distance between the connecting part with the arm and the tip of the bucket) as L3. The angle formed by boom 8 and the XY plane (the relative angle between the straight line in the length direction and the XY plane) is defined as rotation angle α, the angle formed by arm 9 and boom 8 (the relative angle of the straight line in the length direction) as rotation angle β, the angle formed by bucket 10 and arm 9 (the relative angle of the straight line in the length direction) as rotation angle γ, and the angle formed by lower running body 11 and upper rotating body 12 (the relative angle between the center line of front device 1A and the X-axis when looking down on the XY plane from above the Z-axis; see FIG. 4A) as rotation angle (relative angle) θ. As a result, the coordinates of the bucket toe position in the excavator coordinate system and the posture of the front working implement 1A can be expressed by L0, L1, L2, L3, α, β, γ, and θ.

[0036] Furthermore, the inclination of the vehicle body 1B of the hydraulic excavator 1 in the front-rear direction relative to the horizontal plane is defined as an angle (inclination angle) φ (see FIG. 4A).

[0037] <Controller 40> FIG. 5 is a configuration diagram of a system provided in a hydraulic excavator according to the first embodiment of the present invention.

[0038] The system of Figure 5 includes an attitude detection device 60, operating devices 22, 23, an engine speed setting device 480 provided in the driver's cab 120 for setting the engine speed, a control controller (control device) 40 which is a computer that manages control, an engine control controller 470 that controls the speed of the engine 18 and the like in response to control signals from the control controller 40, and electromagnetic proportional valves 50 to 55 that cause the operation of each actuator (3 to 7) in response to control signals from the control controller 40.

[0039] The posture detection device 60 is made up of a boom angle sensor 30, an arm angle sensor 31, a bucket angle sensor 32, a vehicle body inclination angle sensor 33, and a swing angle sensor 34. These angle sensors 30, 31, 32, 34 and the inclination angle sensor 33 function as posture sensors that detect the posture of the front working implement 1A.

[0040] The hydraulic excavator 1 is equipped with a control switching device 650 that switches the operation state of the hydraulic excavator 1 between an on-board operation state and an automatic control state. The control switching device 650 is provided, for example, in the operator's cab 120. When the on-board operation state is selected, the hydraulic excavator 1 operates the operation devices 22, 23 by an operator on board in the operator's cab 12, and operates based on signals output from these operation devices 22, 23, and when the automatic control state is selected, the hydraulic excavator 1 operates based on signals received by a communication device 670, which will be described later, regardless of the operation of the operation devices 22, 23 by the operator.

[0041] Furthermore, automatic control includes automatic travel control, which automates travel operations, and automatic work control (automatic excavation control), which automates excavation work, as will be described later.

[0042] The hydraulic excavator 1 is equipped with a self-location detection device 660 that detects the position and orientation of the hydraulic excavator 1. The self-location detection device 660 may be configured, for example, with a Global Navigation Satellite System (GNSS), or may be configured to detect its own position using Simultaneous Localization and Mapping (SLAM) with a LiDAR or a stereo camera.

[0043] The hydraulic excavator 1 is equipped with communication devices 670, 671 that communicate with an external system (in other words, that connect the hydraulic excavator 1 to the external system so that they can communicate with each other). The communication devices 670, 671 may be installed in the hydraulic excavator 1 or may be installed outside the hydraulic excavator 1. Furthermore, the communication device (receiving unit) 670 and the communication device (transmitting unit) 671 may be configured as a single component or may be configured as separate components. The communication device (receiving unit) 670 receives signals related to automatic control of the hydraulic excavator 1 from the external system. The communication device (transmitting unit) 671 transmits the status (vehicle information) of the hydraulic excavator 1 to the external system.

[0044] 5, the controller 40 has an input unit 91, a central processing unit (CPU) 92 which is a processor, a read-only memory (ROM) 93 and a random access memory (RAM) 94 which are storage devices, and an output unit 95. The input unit 91 receives signals from the angle sensors 30-32, 34 and the tilt angle sensor 33 which are the attitude detection device 60, signals indicating the amount of operation from the operation devices 22, 23, a signal from the engine speed setting device 480, a signal from the control switching device 650, a signal from the self-position detection device 660, and a signal from the communication device 670, and converts them so that the CPU 92 can perform calculations. The ROM 93 is a recording medium that stores a control program for executing control content including processing according to flowcharts described below, and various information necessary for executing the flowcharts, and the like. The CPU 92 performs predetermined calculations on the signals received from the input unit 91 and the memories (93, 94) in accordance with the control program stored in the ROM 93. The output unit 95 creates an output signal according to the calculation result in the CPU 92, and drives and controls the engine 18 and the hydraulic actuators (3 to 7) by outputting the signal to the engine control controller 470 and the electromagnetic proportional valves 50 to 55. The output unit 95 transmits the calculation result in the CPU 92 to a communication device 671, thereby transmitting the state of the hydraulic excavator 1 to the outside of the hydraulic excavator 1 (external system).

[0045] Although the controller 40 in FIG. 5 includes semiconductor memories such as a ROM 93 and a RAM 94 as storage devices, any other storage device can be substituted, and for example, a magnetic storage device such as a hard disk drive may be included.

[0046] 6 and 7 are functional block diagrams of the control controller 40. Fig. 6 shows a functional block diagram executed when the control switching device 650 is in an on-board operation state (when manually operated by an on-board operator), and Fig. 7 shows a functional block diagram executed when the control switching device 650 is in an automatic control state (when the vehicle is operating automatically without operator operation).

[0047] The controller 40 includes an electromagnetic proportional valve control unit 44 , an automatic control calculation unit 700 , a target operation calculation unit 710 , and an engine rotation speed setting unit 740 .

[0048] The engine speed setting unit 740 (FIG. 6) sets a target engine speed based on a signal from the engine speed setting device 480, and outputs a signal corresponding to the set target engine speed to the engine controller 470.

[0049] The target operation calculation unit 710 (Fig. 6) calculates and outputs target control pressures for the electromagnetic proportional valves 50 to 55 corresponding to the operation of the operation devices 22, 23, based on the operation signals output from the operation devices 22, 23 and the signal from the attitude detection device 60. Specifically, the calculation contents are set in advance as a table of target control pressures for the electromagnetic proportional valves corresponding to operation signals as shown in Fig. 8, and the target control pressures for the electromagnetic proportional valves 50 to 55 are output in accordance with this.

[0050] The automatic control calculation unit 700 (Figure 7) performs various calculations to execute automatic control based on signals received from the communication device 670, signals from the attitude detection device 60, and signals from the self-position detection device 660, and outputs the calculation results (target control pressures of the electromagnetic proportional valves 50 to 55, the state of the hydraulic excavator 1, etc.).

[0051] The automatic control calculation unit 700 includes an automatic control execution management unit 701, a stability determination unit 702, an automatic travel control unit 703, and an automatic excavation control unit (automatic work control unit) 704.

[0052] An automatic control execution management unit 701 manages which control to execute among the stability determination unit 702, the automatic travel control unit 703, and the automatic excavation control unit 704. Details will be explained later in the control flowchart.

[0053] The stability determination unit 702 determines whether the footing is stable (footing stability) when executing automatic control to be executed later (for example, automatic excavation control 704). Details will be explained later in the control flowchart.

[0054] The automatic traveling control unit 703 calculates target control pressures for the electromagnetic proportional valves 54, 55 for automatic traveling to the target position, based on the target position received from the communication device 670 and a signal from the self-position detection device 660. Specifically, for example, the right traveling hydraulic motor 3a and the left traveling hydraulic motor 3b are first operated in different directions so that the current orientation of the lower traveling body 11 matches the orientation to the target position, and after the orientation of the lower traveling body 11 matches the direction to the target position, the traveling hydraulic motors 3a, 3b are operated in the forward direction to travel to the target position.

[0055] The automatic excavation control unit (automatic work control unit) 704 calculates target control pressures for the electromagnetic proportional valves 50 to 53 for performing automatic excavation, based on the target position received from the communication device 670 and the signal from the attitude detection device 60. Specifically, for example, it calculates the bucket tip (toe) position P (see FIGS. 4A and 4B) using the result from the attitude detection device 60, and calculates the direction for heading toward the target position. It then calculates how the actuators of the hydraulic excavator 1 should be operated to move the hydraulic excavator 1 in that direction, calculates target control pressures for the electromagnetic proportional valves 50 to 53 to achieve this, and operates the hydraulic excavator 1.

[0056] The electromagnetic proportional valve control unit 44 (Figures 6 and 7) outputs control command values ​​for the corresponding electromagnetic proportional valves 50 to 55 in accordance with the target control pressure output by the target operation calculation unit 710 or the automatic control calculation unit 700 (the automatic travel control unit 703 and the automatic excavation control unit 704).

[0057] <Control flowchart> 9 and 10 show control flowcharts of the automatic control execution management unit 701 and the stability determination unit 702 of the first embodiment.

[0058] The control flowchart of the automatic control execution management unit 710 in FIG. 9 will be described.

[0059] In S400, the execution order and control parameters of the automatic control are received from an external system via the communication device 670 (see the upper diagram of FIG. 11 for a specific example).

[0060] In S410, the received execution order of automatic control is referenced to determine whether there is a location where automatic excavation control follows automatic travel control. If there is a location where automatic excavation control follows automatic travel control (YES), proceed to S420, and if there is no location where automatic excavation control follows automatic travel control (NO), proceed to S430.

[0061] In S420, a stability determination is inserted (execution registered) between the automatic driving control and the automatic excavation control (that is, after the automatic driving control and before the automatic excavation control) (see the lower diagram of FIG. 11 as a specific example).

[0062] In S430, the execution order and control parameters of the automatic control are determined, and are transmitted to the external system by the communication device 671, and the process transitions to a state of waiting for reception of an automatic control start command from the external system.

[0063] In S440, it is checked periodically whether an automatic control start command has been received from an external system via the communication device 670. If it has been received (YES), the process proceeds to S450; if it has not been received (NO), the process returns to S430.

[0064] In S450, the automatic control (stability determination unit 702, automatic driving control unit 703, automatic excavation control unit 704) is executed according to the execution order determined in S430. If the execution order of the automatic control received from the external system in S400 includes a location where automatic excavation control follows automatic driving control, the stability determination unit 702 will be executed after the automatic driving control unit 703 is executed and before the automatic excavation control unit 704 is executed.

[0065] The control flow chart of the stability determining unit 702 in FIG. 10 will be described.

[0066] In S500, a determination operation for evaluating stability is executed. The determination operation is a preset operation, such as an operation of raising and lowering the boom 8 in a predetermined posture or an operation of rotating the upper rotating body 12 one revolution in a predetermined posture. During this operation (while the operation preset for stability determination is being performed), data (vehicle body information) to be used for the determination is measured. Specifically, for example, the tilt angle φ of the upper rotating body 12 (vehicle body 1B) is measured.

[0067] In S510, a stability determination threshold is acquired according to the content of automatic control to be executed after the stability determination. The stability determination threshold is set in advance for each content of automatic control to be executed after the stability determination is executed. For example, when automatic control requiring precision is executed, a small (strict) value is set as the threshold, and when automatic control not requiring precision is executed, a large (lenient) value is set as the threshold.

[0068] In S520, it is determined whether the stability is within an acceptable range based on the data acquired in S500 and the stability determination threshold of S510. If the stability is acceptable, that is, the data acquired in S500 is within the stability determination threshold of S510 (YES), the process ends. If the stability is not acceptable, that is, the data acquired in S500 exceeds the stability determination threshold of S510 (NO), the process proceeds to S530.

[0069] In S530, the process that was scheduled to be executed after the stability determination (in this example, automatic control of automatic excavation control) is interrupted, and the process proceeds to S540.

[0070] In S540, a message is sent to the external system via the communication device 671 that the process (in this example, automatic control of automatic excavation control) has been interrupted.

[0071] <Actions and Effects> An example of the operation of the first embodiment will be described below with reference to FIGS.

[0072] The upper diagram in Fig. 11 shows an example of the content that the external system transmits to the hydraulic excavator 1. In this operation example, the external system issues a command to the hydraulic excavator 1 to perform automatic travel to point (Tx1, Ty1), then automatic travel to point (Tx2, Ty2), and then perform automatic excavation control so as to pass through points (Dx1, Dy1, Dz1) to (Dx3, Dy3, Dz3).

[0073] In S400, the automatic control execution management unit 701 receives the command shown in the upper diagram of FIG. 11 from an external system.

[0074] In S410, since No. 3 automatic excavation follows No. 2 automatic driving in the upper diagram of Figure 11, the process proceeds to S420, inserts a stability judgment into No. 3 (execution registration) as shown in the lower diagram of Figure 11, and in S430, the process waits for an automatic control start command from the external system.

[0075] When an automatic control start command is issued from an external system, the determination in S440 becomes YES, and in S450, automatic control is executed in the order of Nos. 1 to 6 in the lower diagram of FIG.

[0076] For Nos. 1 and 2, automatic driving control (automatic driving control unit 703) is executed so that the vehicles head towards their respective target positions.

[0077] At No. 3, a stability determination (stability determination unit 702) is performed.

[0078] An example of the stability determination operation will be described below.

[0079] In S500, a determination operation is executed, and the tilt angle φ of the upper rotating body 12 (vehicle body 1B) is measured during the execution.

[0080] In S510, a stability determination threshold value is acquired. Here, it is assumed that the threshold value TH is acquired.

[0081] (1) If the measurement result of S500 is as shown in Figure 12 As shown in Figure 12, since the magnitude of the tilt angle φ of the upper rotating body 12 is less than the threshold value TH throughout the entire judgment operation execution section, it is determined to be stable in S520, and the processing of No. 3 stability judgment (stability judgment unit 702) is terminated.

[0082] Thereafter (that is, following the stability determination of No. 3), the automatic excavation control of Nos. 4 to 6 (automatic excavation control unit 704) is executed.

[0083] (2) If the measurement result of S500 is as shown in Figure 13 As shown in FIG. 13, the magnitude of the tilt angle φ of the upper swing structure 12 exceeds the threshold value TH in the section t1 to t2 within the determination operation execution section, so it is determined in S520 that the system is not stable, and the process proceeds to S530.

[0084] In S530, the execution of the automatic excavation control (automatic excavation control unit 704) of Nos. 4 to 6 that was scheduled to be executed (after the stability determination of No. 3) is interrupted, and in S540, the fact that the execution of the automatic excavation control (automatic excavation control unit 704) of Nos. 4 to 6 has been interrupted is notified to the external system via the communication device 671.

[0085] As described above, the automatic control system for a hydraulic excavator (work machine) 1 of this embodiment is an automatic control system for a work machine comprising a work machine having a plurality of driven members driven by a plurality of actuators (3 to 7), and a control device that controls the work machine, wherein the control device comprises an automatic travel control unit 703 that controls the automatic travel of the work machine, an automatic work control unit (automatic excavation control unit 704) that controls the automatic work of the work machine, and a stability determination unit 702 that determines the stability of the footing of the work machine, and when automatic work control is to be performed by the automatic work control unit (automatic excavation control unit 704) after automatic travel control is performed by the automatic travel control unit 703, a stability determination is performed by the stability determination unit 702 before the automatic work control is performed, and automatic control of the work machine is performed (by at least one of the automatic work control unit (automatic excavation control unit 704) or the automatic travel control unit 703) based on the determination result of the stability determination unit 702.

[0086] Furthermore, when automatic work control is performed after automatic driving control in the execution order of the automatic control of the work machine, the control device performs a stability determination by the stability determination unit 702 after the automatic driving control and before the automatic work control, so that after the automatic driving control unit 703 performs the automatic driving control, the stability determination by the stability determination unit 702 is performed before the automatic work control unit (automatic excavation control unit 704) performs the automatic work control.

[0087] Furthermore, the stability determination unit 702 determines the stability based on (dynamic) vehicle body information (for example, tilt angle φ) acquired when the work machine performs a predetermined determination operation.

[0088] Furthermore, the stability determination unit 702 determines the stability based on the inclination angle φ of the work machine measured by a measuring device (vehicle body inclination angle sensor 33) that measures the inclination angle φ of the work machine when the work machine performs a predetermined determination operation (for example, while the work machine is performing a predetermined determination operation).

[0089] Furthermore, if the stability determination unit 702 determines that the system is not stable, it suspends automatic control (after the scheduled stability determination) and notifies the external system of the suspension via the communication device 671 that communicates with the external system.

[0090] In the automatic control system for the hydraulic excavator 1 configured as described above, it is possible to prevent the automatic control from being started on unstable footing, thereby preventing workability from being impaired.

[0091] [Second embodiment] The second embodiment will be described with reference to FIGS.

[0092] FIG. 14 is a functional block diagram of the controller 40, and shows a functional block diagram executed when the control switching device 650 is in an automatic control state (during automatic operation without operator operation).

[0093] As shown in FIG. 14, the second embodiment differs from the first embodiment in that it includes a topographical measuring device 680 .

[0094] The topography measuring device 680 measures the topography around (near) the hydraulic excavator 1 and outputs the measurement data to the automatic control calculation unit 700 of the controller 40, and is composed of a LiDAR, a stereo camera, a millimeter wave radar, an ultrasonic sensor, etc. The topography measuring device 680 may be installed on the hydraulic excavator 1, or may be installed outside the hydraulic excavator 1 so that it can measure the area around the hydraulic excavator 1.

[0095] The automatic control calculation unit 700 also includes an automatic leveling control unit (automatic ground leveling control unit) 705.

[0096] The automatic leveling control unit (automatic ground leveling control unit) 705 performs the operation of leveling the ground around the hydraulic excavator 1 using the bucket 10, and is configured to output target control pressures for the electromagnetic proportional valves 50 to 55 so as to perform, for example, a pre-programmed leveling operation (ground leveling operation).

[0097] In the second embodiment, stability is determined using the results of terrain measurement by the terrain measurement device 680 as a method for evaluating stability. Unlike the first embodiment, in the second embodiment, before the final target position (also referred to as the final destination position) of automatic driving is reached, the terrain measurement device 680 is used to measure the terrain near the final destination position. Therefore, in S420 of FIG. 9, the automatic control execution management unit 710 of the second embodiment executes the stability determination unit 702 to perform terrain measurement using the terrain measurement device 680 when the vehicle reaches a position (Tx2', Ty2') that is a predetermined distance Ls away from (before) the target position of automatic driving control (see FIG. 16).

[0098] Details of the stability determination unit 702 of the second embodiment will be described below with reference to the control flowchart of FIG.

[0099] In S501, the terrain measurement device 680 is used to measure the terrain of the final target position of the automatic driving or the terrain in the vicinity thereof.

[0100] In S511, the stability determination threshold value TH is acquired in the same manner as in the first embodiment.

[0101] In S521, it is determined whether the distance from the reference value in the height direction is equal to or less than the threshold value TH as a result of the terrain measurement. If the distance from the reference value in the height direction is equal to or less than the threshold value TH as a result of the terrain measurement, that is, if the stability is acceptable (YES), the process ends. If the distance from the reference value in the height direction is greater than the threshold value TH as a result of the terrain measurement, that is, if the stability is not acceptable (NO), the process proceeds to S531.

[0102] In S531, the automatic leveling control unit 705 executes automatic leveling control, thereby leveling (leveling) the ground at or near the final target position of automatic traveling.

[0103] <Actions and Effects> An example of the operation of the second embodiment will be described with reference to FIGS.

[0104] As in the first embodiment, the automatic control execution management unit 701 receives the command shown in the upper diagram of FIG. 11 from an external system.

[0105] As in the first embodiment, the automatic control execution management unit 701 makes an execution plan for automatic control as shown in the right diagram of Fig. 16. Unlike the first embodiment, the second embodiment inserts (execution registered) a stability assessment into No. 3 so that the automatic driving of No. 2 can be temporarily stopped at point (Tx2', Ty2') to perform a stability assessment, and executes automatic driving so that No. 4 can travel the remaining section (Ls).

[0106] When an automatic control start command is issued from an external system, automatic driving control (automatic driving control unit 703) is executed to move toward each of the target positions No. 1 and No. 2, and then stability determination (stability determination unit 702) is executed No. 3.

[0107] In S501, the terrain measurement device 680 is used to measure the terrain at or near the travel target position.

[0108] In S511, the stability determination threshold TH is acquired in the same manner as in the first embodiment.

[0109] In S521, stability is determined. The measurement results of S501 are shown in Figure 17. The measurement results are shown in a site coordinate system XlYlZl linked to the work site (for example, a reference point at the work site is the origin, with Xl pointing east, Yl pointing north, and Zl pointing vertically upward). In the second embodiment, the absolute values ​​of the Zl values ​​from these measurement results are calculated, and it is determined whether all of the absolute values ​​of these Zl values ​​are equal to or less than the threshold value TH.

[0110] (1) When the absolute values ​​of Zl are all less than the threshold value TH The process of the stability determination (stability determination unit 702) of No. 3 is ended, and automatic traveling toward the target position of No. 4 is resumed. That is, automatic traveling is performed from the determination execution position (Tx2', Ty2') to the traveling target position (Tx2, Ty2).

[0111] (2) If there is a point where the absolute value of Zl is greater than the threshold value TH In S531, the automatic leveling control (automatic leveling control unit 705) is executed to perform pre-programmed operations and level the ground. After that, automatic travel toward the target position No. 4 is resumed. In other words, after the ground at the travel target position (Tx2, Ty2) is leveled (leveled) at the judgment execution position (Tx2', Ty2'), automatic travel is executed from the judgment execution position (Tx2', Ty2') to the travel target position (Tx2, Ty2).

[0112] As described above, in the automatic control system for the hydraulic excavator 1 of this embodiment, the stability determination unit 702 determines the stability based on the results of terrain measurement by the terrain measurement device 680 that measures the terrain around the work machine.

[0113] Furthermore, if the stability determination unit 702 determines that the work machine is not stable, it executes an automatic ground leveling control unit (automatic leveling control unit 705) that levels (levels) the ground around the work machine.

[0114] In this case, even if it is determined that the footing is unstable, the ground of the footing can be leveled (made smooth) to ensure stability, and then automatic control can be continued (without interrupting automatic control).

[0115] In the automatic control system for the shovel 1 configured as described above, similarly to the first embodiment, it is possible to prevent the automatic control from being started on unstable footing, thereby preventing the workability from being impaired.

[0116] [Third embodiment] The third embodiment will be described with reference to FIGS.

[0117] The third embodiment differs from the first and second embodiments in that the hydraulic excavator 1 is equipped with a blade (blade) (not shown), and is configured to automatically control the excavator to level the footing using the blade when the footing at the work site is determined to be unstable. The hydraulic excavator 1 is equipped with an operating device 22c for operating the blade.

[0118] The operating device 22c (see FIG. 18) is an electric lever type that generates an electric signal corresponding to the amount and direction of operation by the operator. The electric signal thus generated is input to the control controller 40, which then outputs an electric signal to the solenoid valve unit 160 to drive the solenoid proportional valves 56a, 56b (see FIG. 19) corresponding to the operation input to the operating device 22c. The solenoid proportional valves 56a, 56b supply the input electric signal to hydraulic actuators 156a, 156b of the corresponding flow control valves 15g via pilot lines 146a, 146b, and the signal is used as a control signal to drive these flow control valves 15g.

[0119] The pressure oil discharged from the hydraulic pump 2 is supplied to the blade cylinder 19 via the flow control valve 15g. The supplied pressure oil causes the blade cylinder 19 to expand and contract, thereby rotating the blade and changing the position and attitude of the blade.

[0120] The blade cylinder 19 is provided with pressure sensors 16m and 16n to detect its actuator pressure. The pressure sensors 16m and 16n detect the pressure on the bottom side and the pressure on the rod side of the blade cylinder 19, respectively, and output the results as electrical signals to the controller 40 (in FIG. 18, the connection lines from the pressure sensors 16m and 16n to the controller 40 are not shown due to space limitations).

[0121] As shown in FIG. 19, the solenoid valve unit 160 has a primary port side connected to the pilot pump 48 via the pump line 130, and is equipped with solenoid proportional valves 56a and 56b that reduce the pilot pressure from the pilot pump 48 and output it to pilot lines 146a and 146b.

[0122] The pilot lines 146a and 146b are provided with pressure sensors 17m and 17n so as to detect the output pressures of the electromagnetic proportional valves 56a and 56b.

[0123] FIG. 20 is a functional block diagram of the controller 40, and shows a functional block diagram executed when the control switching device 650 is in an automatic control state (during automatic operation without operator operation).

[0124] In the third embodiment, unlike the second embodiment, the automatic control calculation unit 700 is equipped with an automatic finishing control unit (automatic work control unit) 706 and an automatic earth removal travel control unit (automatic leveling control unit) 707 (instead of the automatic excavation control unit 704 and the automatic leveling control unit 705).

[0125] The automatic finishing control unit (automatic work control unit) 706 has the same function as the automatic excavation control unit 704, but is a control unit that places more emphasis on accuracy than the automatic excavation control unit 704, and a stricter stability determination threshold value THl (<threshold value TH) is set.

[0126] The automatic earth removal travel control unit (automatic ground leveling control unit) 707 uses a blade (instead of the bucket 10) to level the ground around the hydraulic excavator 1, and is configured to output target control pressures for the electromagnetic proportional valves 54 to 56 so as to perform, for example, a pre-programmed leveling operation (ground leveling operation).

[0127] The third embodiment is similar to the second embodiment in that a stability evaluation method uses the results of terrain measurement by the terrain measurement device 680 to determine stability. In the third embodiment, because terrain measurement is performed using the terrain measurement device 680, the automatic driving control is divided as in the second embodiment, and stability determination is performed in between (see FIG. 16).

[0128] Details of the stability determination unit 702 of the third embodiment will be described below with reference to the control flowchart of FIG.

[0129] In S502, the terrain measurement device 680 is used to measure the terrain at or near the travel target position (final target position).

[0130] In S512, unlike the first and second embodiments, the stability determination threshold THl (<threshold TH) is acquired.

[0131] In S522, a variable for counting the number of times stability determination is made is initialized (set to 0).

[0132] In S532, the stability is determined in the same manner as in the second embodiment (S521). If the stability is acceptable as a result of the stability determination (YES), the process ends. If the stability is not acceptable (NO), the process proceeds to S542.

[0133] In S542, the automatic earth unloading travel control is executed by the automatic earth unloading travel control unit 707. As a result, the ground at or near the travel target position (final target position) is leveled (leveled).

[0134] In S552, the stability is determined in the same manner as in S532. If the stability determination result indicates that the stability is acceptable (YES), the process ends. If the stability is not acceptable (NO), the process proceeds to S562.

[0135] In S562, it is determined whether the number of stability determinations (corresponding to the number of times the automatic earth unloading travel control of the automatic earth unloading travel control unit 707 has been executed) is equal to or greater than a predetermined number. If it is equal to or greater than the predetermined number (YES), the process proceeds to S582, and if it is less than the predetermined number (NO), the process proceeds to S572.

[0136] In S572, the number of stability determination determinations is incremented by 1, and the process proceeds to S542, where the automatic earth unloading travel control is executed by the automatic earth unloading travel control unit 707. As a result, the automatic earth unloading travel control by the automatic earth unloading travel control unit 707 is repeatedly executed until it is determined that the stability is acceptable, or until the number of stability determination determinations (corresponding to the number of times the automatic earth unloading travel control by the automatic earth unloading travel control unit 707 is executed) exceeds a predetermined number of times.

[0137] In S582, the automatic control that has been registered since the stability determination is suspended, and the process proceeds to S592.

[0138] In S592, the external system is notified via the communication device 671 that the automatic control has been suspended.

[0139] <Actions and Effects> As described above, in the automatic control system for the hydraulic excavator 1 of this embodiment, the stability determination unit 702 determines the stability based on the results of terrain measurement by the terrain measurement device 680 that measures the terrain around the work machine.

[0140] Furthermore, if the stability determination unit 702 determines that the work machine is not stable, it executes an automatic ground leveling control unit (automatic earth removal travel control unit 707) that levels (levels) the ground around the work machine.

[0141] In the third embodiment, unlike the second embodiment, a threshold value TH1 (<threshold value TH) is acquired as a stability determination threshold value in S512, and if the stability determination is determined to be unstable in S532, ground leveling is performed by automatic earth removal travel control (using a blade) in S542. This allows automatic control to be started on a more stable footing.

[0142] In the third embodiment, after leveling the ground with the automatic earth unloading travel control in S542, stability is determined again in S552, and the automatic earth unloading travel control is executed until it is determined to be stable.

[0143] Furthermore, if it is not determined that the automatic earth unloading travel control is stable even after performing it a predetermined number of times, the automatic control is interrupted and the external system is notified via the communication device 671 that the automatic control has been interrupted.

[0144] In the automatic control system for the shovel 1 configured as described above, similarly to the first and second embodiments, it is possible to prevent the automatic control from being started on unstable footing, thereby preventing workability from being impaired.

[0145] [Fourth embodiment] The fourth embodiment will be described with reference to Fig. 22. Unlike the second and third embodiments, the fourth embodiment is basically configured to ensure stability of the scaffolding without performing automatic ground leveling control such as automatic leveling control using the bucket 10 or automatic earth removal travel control using a blade.

[0146] Details of the stability determination unit 702 of the fourth embodiment will be described below with reference to the control flowchart of FIG.

[0147] In S503, the determination operation is performed in the same manner as in S500 in the first embodiment. The subsequent S513 is the same as in S510 in the first embodiment, and S533 and S553 are the same as in S520 in the first embodiment. In addition, S523, S563, S573, S583, and S593 are the same as in S522, S562, S572, S582, and S592 in the third embodiment.

[0148] Furthermore, in S543, instead of performing automatic earth unloading travel control (S542), automatic travel control (automatic travel control unit 703) is executed only in a predetermined direction and distance. In other words, in S543, the travel target position of the automatic travel control is changed from the initial position (by a predetermined direction and distance), and automatic travel control (automatic travel control unit 703) is executed. The predetermined direction and predetermined distance in S543 can be determined based on a position where post-processing automatic excavation control can be executed even if the location is moved, and can be calculated based on the bucket tip (toe) position P (see Figures 4A and 4B) and the coordinates of the target position (see Figure 11), etc. This makes it possible to ensure footing stability with just simple automatic control that performs automatic travel control only for a predetermined distance, without performing automatic ground leveling control such as automatic leveling control using the bucket 10 or automatic earth unloading travel control using a blade.

[0149] <Actions and Effects> As described above, in the automatic control system of the hydraulic excavator 1 of this embodiment, if the stability determination unit 702 determines that the system is not stable, the automatic driving control unit 703 changes the target driving position from the initial position and performs automatic driving control by the automatic driving control unit 703.

[0150] Furthermore, the amount of change in the travel target position of the automatic travel control unit 703 is set based on the dimensions of the plurality of driven members (such as bucket tip (toe) position P).

[0151] That is, as shown in FIG. 22, if it is determined in S533 that the vehicle is not stable, automatic travel control is performed for a predetermined distance in S543. Also, as in the third embodiment, the automatic travel control of the automatic travel control unit 703 is repeatedly performed until it is determined that the stability is acceptable, or until the number of stability determinations (corresponding to the number of times the automatic travel control of the automatic travel control unit 703 has executed the control) exceeds a predetermined number. If it is not determined that the vehicle is stable even after executing the automatic travel control a predetermined number of times (even when the number of times the automatic travel control unit 703 has executed the control exceeds a predetermined number), the automatic control is interrupted, and the fact that the automatic control has been interrupted is notified to an external system via the communication device 671. This makes it possible to start automatic control on a stable footing through simple automatic control (automatic travel control).

[0152] In the automatic control system for the shovel 1 configured as described above, similarly to the first to third embodiments, it is possible to prevent the automatic control from being started on unstable footing, thereby preventing the workability from being impaired.

[0153] In the first to fourth embodiments described above, angle sensors are used to detect the angles of the boom 8, arm 9, and bucket 10, but posture information of the hydraulic excavator 1 may be calculated using a cylinder stroke sensor instead of an angle sensor. Also, although an electric lever type hydraulic excavator 1 has been described as an example, in the case of a hydraulic pilot type excavator, a configuration may be adopted in which a command pilot pressure generated from the hydraulic pilot is controlled.

[0154] The components of the controller 40, as well as their functions and execution processes, may be partially or entirely implemented by hardware (for example, by designing logic for executing each function as an integrated circuit). The components of the controller 40 may also be implemented as a program (software) that is read and executed by an arithmetic processing device (for example, a CPU) to implement the functions of the controller 40. Information related to the program may be stored in, for example, a semiconductor memory (flash memory, SSD, etc.), a magnetic storage device (hard disk drive, etc.), or a recording medium (magnetic disk, optical disk, etc.).

[0155] In the above first to fourth embodiments, various examples have been shown for determining stability and for dealing with the situation when it is determined that stability is not established, but various other combinations may be used in addition to the combinations shown in the first to fourth embodiments.

[0156] In the first to fourth embodiments, the stability determination means determines whether the inclination angle φ of the upper rotating body 12 measured by the vehicle body inclination angle sensor 33 or the measurement value when measuring the terrain by the terrain measurement device 680 falls within a range of the threshold value TH (or threshold value THl) relative to the reference, but it may also be configured to compare the difference between the maximum and minimum values ​​within a certain section of the measurement data with the threshold value.

[0157] In the first embodiment, the stability determination means uses the inclination angle φ in the longitudinal direction of the upper rotating body 12, but the determination may also be made using the inclination angle in the lateral direction of the upper rotating body 12, or the inclination angle in the longitudinal direction or the lateral direction of the lower running body 11.

[0158] Here, a variation of the stability evaluation method using the tilt angle φ will be added. In the first embodiment described above, stability is determined directly using the value (absolute value) of the tilt angle φ, but stability may also be determined as follows.

[0159] <Modification 1 of Stability Determination Method> As shown in Figure 23, for the inclination angle φ within the judgment operation execution section, the largest deviation dφ from the inclination angle φ at the start of the judgment operation execution is found, and if this deviation dφ (absolute value) is greater than a predetermined threshold THm, it is determined that the stability is unacceptable, and if it is equal to or less than the threshold THm, it is determined that the stability is acceptable.

[0160] The method of determining stability based only on the absolute angle, as in the first embodiment, is considered to be capable of making a determination on flat ground, but the validity of the determination may decrease when the ground is inclined, such as on a slope. This first variation of the stability determination method is considered to improve the validity of determination on slopes because it is possible to determine the amount of excess tilt based on the tilt angle φ at the start of the determination operation. However, since the tilt angle changes significantly when turning on a slope, it is difficult to determine stability during a turning operation. This first variation of the stability determination method is considered to be preferable for determining the stability of, for example, a boom-raising or lowering operation.

[0161] <Modification 2 of Stability Determination Method> As shown in Figure 24, after the judgment operation execution section, the tilt angle φ is measured for a preset settling judgment time. The vertical axis in Figure 24 is the angle φr, which is the tilt angle φ minus the tilt angle φ0 at the time the judgment operation is executed. Within the settling judgment time, the time until the angle φr falls between the judgment threshold -THp and the judgment threshold THq is defined as the settling time, and stability is judged based on whether this settling time is longer than a predetermined time.

[0162] If the settling time is greater than a predetermined time, the stability is determined to be unacceptable, and if the settling time is equal to or less than the predetermined time, the stability is determined to be acceptable.

[0163] In the second variation of the present stability determination method, the determination is made based on the settling time of the angle φr, but the settling time may also be determined using the angular velocity obtained by differentiating the angle φr or the angular acceleration obtained by differentiating the angular velocity. Also, the angular velocity may be measured directly using, for example, a gyro sensor.

[0164] Further, instead of the angular acceleration, the acceleration obtained from an acceleration sensor may be measured and used to determine the settling time.

[0165] In the second variation of the stability determination method, stability is determined from dynamic behavior, and unlike the first variation of the stability determination method, stability can also be determined for turning operations.

[0166] <Modification 3 of Stability Determination Method> The stability may be evaluated by combining any of the first embodiment, Modification 1, Modification 2, and variations of Modification 2, which relate to the stability determination method. That is, the stability may be determined to be acceptable only when all determination results indicate that the stability is acceptable, and may be determined to be unacceptable when even one result indicates that the stability is unacceptable.

[0167] Furthermore, the determination operation may be associated in advance with one or more determination methods, and the determination may be made based on the determination results of the determination methods.

[0168] In the first to fourth embodiments described above, the control parameters for executing the automatic travel control, automatic excavation control, and automatic finishing control are received as target positions, and control is performed accordingly. However, the control parameters may be omitted and predetermined operations may be performed, or parameters required for operating the hydraulic excavator 1 may be received as control parameters, such as the target control pressure of each electromagnetic proportional valve, the target angular velocity of the actuator, the angular velocity of each rotating part, the bucket toe position P, and the velocity vector of the position of the connecting pin between the bucket 10 and the arm 9.

[0169] In the second and third embodiments, the automatic leveling control and automatic earth unloading travel control, which are automatic controls for leveling the ground, are configured to be executed immediately after it is determined that the ground is not stable, but the automatic ground leveling control may also be configured to communicate with an external system and perform the automatic ground leveling control based on commands from the external system.

[0170] In the fourth embodiment, if it is determined that the footing is not stable, the robot is configured to automatically travel a predetermined direction and distance. However, it may also be configured to use a topography measurement device 680 to estimate a location where the footing is stable, and automatically travel to that estimated location.

[0171] In the first to fourth embodiments, the automatic control calculation unit 700 that executes automatic control of the hydraulic excavator 1 is implemented in the control controller 40 mounted on the hydraulic excavator 1, but the location of implementation is not limited to this, and it may be implemented in an external system such as a cloud or a server, and configured to send a signal from the external system to the hydraulic excavator 1 via the communication device 670 to operate the hydraulic excavator 1.

[0172] The present invention is not limited to the above-described embodiments and includes various modifications. For example, the above-described embodiments have been described in detail to clearly explain the present invention, and are not necessarily limited to those including all of the described configurations. Furthermore, it is possible to replace part of the configuration of one embodiment with the configuration of another embodiment, or to add the configuration of another embodiment to the configuration of one embodiment. Furthermore, it is possible to add, delete, or replace part of the configuration of each embodiment with other configurations. [Explanation of symbols]

[0173] 1... Hydraulic excavator (work machine) 1A...Front work device 1B...Body 8...Boom 9...Arm 10...Bucket 11...Undercarriage 12...Upper rotating body 16a~16l...Pressure sensor 17a~17l...Pressure sensor 22, 23...Operating device 30...Boom angle sensor 31...Arm angle sensor 32...Bucket angle sensor 33...Vehicle body tilt angle sensor (measuring device) 34...Rotation angle sensor 40...Controller (control device) 44...Electromagnetic proportional valve control section 50, 51, 52, 53, 54, 55, 56...Solenoid proportional valve 60...Attitude detection device 470...Engine control controller 480...Engine RPM setting device 650...Control switching device 660...Self-position detection device 670...Communication device (receiving unit) 671...Communication device (transmitter) 680...Topographical measurement device 700...Automatic control calculation unit 701...Automatic Control Execution Management Department 702...Stability judgment section 703...Automatic driving control unit 704...Automatic excavation control unit (automatic work control unit) 705...Automatic leveling control unit (automatic ground leveling control unit) 706...Automatic finishing control unit (automatic work control unit) 707...Automatic earth removal travel control unit (automatic ground leveling control unit)

Claims

1. a work machine having a plurality of driven members driven by a plurality of actuators; a control device for controlling the work machine, The control device an automatic travel control unit that performs automatic travel of the work machine; an automatic operation control unit that performs automatic operations of the work machine; a stability determination unit that determines the stability of the scaffolding of the work machine, An automatic control system for a work machine, characterized in that when automatic work control is performed by the automatic work control unit after automatic travel control is performed by the automatic travel control unit, a stability determination is performed by the stability determination unit before the automatic work control is performed, and automatic control of the work machine is performed based on the determination result of the stability determination unit.

2. 2. The automatic control system for a work machine according to claim 1, An automatic control system for a work machine, characterized in that the stability determination unit determines the stability based on vehicle body information acquired when the work machine performs a predetermined determination operation.

3. 2. The automatic control system for a work machine according to claim 1, an automatic control system for a work machine, characterized in that the stability determination unit determines the stability based on a stability determination threshold that is set in advance depending on the content of automatic control that is executed after performing the stability determination.

4. 2. The automatic control system for a work machine according to claim 1, An automatic control system for a work machine, wherein the stability determination unit determines the stability based on an inclination angle of the work machine measured by a measuring device that measures the inclination angle of the work machine.

5. 2. The automatic control system for a work machine according to claim 1, The stability determination unit determines the stability based on the inclination angle of the work machine measured by a measuring device that measures the inclination angle of the work machine by having the work machine perform a predetermined determination operation.

6. 2. The automatic control system for a work machine according to claim 1, An automatic control system for a work machine, characterized in that, when the stability determination unit determines that the automatic control is not stable, it suspends the automatic control and notifies an external system of the suspension via a communication device that communicates with the external system.

7. 2. The automatic control system for a work machine according to claim 1, An automatic control system for a work machine, wherein the stability determination unit determines the stability based on a topographical measurement result obtained by a topographical measurement device that measures the topography around the work machine.

8. 8. The automatic control system for a work machine according to claim 7, The control device, when automatic work control occurs after automatic driving control in the execution order of the automatic control of the work machine, executes a stability determination by the stability determination unit after automatic driving control to a judgment execution position that is a predetermined distance away from the final target position of the automatic driving control, and before automatic driving control from the judgment execution position to the final target position, thereby executing a stability determination by the stability determination unit after automatic driving control is executed by the automatic driving control unit and before executing automatic work control by the automatic work control unit.

9. 8. The automatic control system for a work machine according to claim 7, When the stability determination unit determines that the terrain is not stable, it repeatedly executes the automatic ground leveling control unit until it determines that the terrain is stable or until the number of times that the automatic ground leveling control unit that levels the terrain around the work machine has been executed exceeds a predetermined number of times that has been set in advance, An automatic control system for a work machine, characterized in that if the automatic ground leveling control unit is not determined to be stable even after the number of times it has been executed exceeds a predetermined number of times, the automatic control is interrupted and an external system is notified of the interruption via a communication device that communicates with the external system.

10. 2. The automatic control system for a work machine according to claim 1, An automatic control system for a work machine, characterized in that, when the stability determination unit determines that the work machine is not stable, the automatic driving control unit changes the target driving position of the automatic driving control unit from its initial position and performs automatic driving control using the automatic driving control unit.

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