Control system for work machine

Abstract

Provided is a control system with which it is possible to suppress any deviation between a target route and the actual movement of a controlled object included in a work machine. This control system comprises an actuator that moves a controlled object, and a controller. The controller is configured to control the actuator so as to move the controlled object in accordance with a target trajectory including information pertaining to a target route and a target speed, calculate a required capacity required for the actuator to move the controlled object in accordance with the target trajectory, and change the target speed to a revised target speed without changing the target route in cases in which the required capacity is outside of an actuator capacity range. The revised target speed is a speed at which the capacity required for the actuator to move the controlled object at the revised target speed falls within the actuator capacity range.

Description

Control system for a work machine

[0001] The present invention relates to a control system for controlling the movement of a work machine.

[0002] Patent Document 1 describes a technique for controlling the movement of a work machine based on a work plan.

[0003] However, there is a risk that the capacity required of the actuator to execute the control will exceed the capacity range of the actuator (for example, a range below the maximum capacity that the actuator can output), which will cause a discrepancy between the target path, which is the target path along which the controlled object should move, and the actual movement of the controlled object moved by the actuator.

[0004] Japanese Patent Application Laid-Open No. 2022-118445

[0005] The present invention aims to provide a control system that performs control to move a controlled object included in a work machine along a target path, and that can suppress the deviation between the target path and the actual movement of the controlled object.

[0006] Provided is a control system for controlling the movement of a controlled object included in a work machine, the control system comprising an actuator that moves the controlled object and a controller. The controller is configured to: control the actuator to move the controlled object according to a target trajectory including information on a target path and a target speed of the controlled object; calculate a required capacity, which is a capacity required of the actuator to move the controlled object according to the target trajectory; and, if the required capacity falls outside an actuator capacity range defined for the actuator, change the target speed to a revised target speed without changing the target path. The revised target speed is a speed at which a revised required capacity, which is a capacity required of the actuator to move the controlled object at the revised target speed, falls within the actuator capacity range.

[0007] Fig. 1 is a side view of a work machine according to an embodiment of the present invention. Fig. 2 is a block diagram showing elements included in a control system, etc. according to the embodiment. Fig. 3 is a diagram showing a hydraulic circuit mounted on the work machine. Fig. 4 is a graph showing the relationship between a target point position and a target arrival time in a work plan set for the work machine. Fig. 5 is a graph showing an example of the relationship between an actuator capacity range set for an actuator in the work machine and a required capacity. Fig. 6 is a flowchart showing processing executed by the controller.

[0008] An embodiment of the present invention will be described with reference to FIGS.

[0009] FIG. 1 shows a work machine 10 according to the embodiment. The work machine 10 is a machine that performs work. The work machine 10 illustrated in FIG. 1 is a construction machine that performs construction work, specifically a hydraulic excavator. The work machine 10 may also be a work machine other than a hydraulic excavator, such as a crane. The work machine 10 is configured so that the operation of the work machine 10 can be automatically controlled. Specifically, the work machine 10 may be configured to be operated automatically, or may be configured to be operated semi-automatically. An example of the semi-automatic operation is machine control, which will be described later. The work machine 10 may have not only a mode in which its operation is automatically controlled, but also a mode in which it operates in response to operation by an operator, or a mode in which it is operated by remote control outside the work machine 10.

[0010] The work machine 10 illustrated in FIG. 1 includes a machine body 10 a , an attachment 15 , an actuator drive unit 17 shown in FIG. 2 , a plurality of actuators, and an engine 39 .

[0011] The machine body 10 a is the main body portion of the work machine 10 , and includes a lower body 11 and an upper rotating body 13 .

[0012] The lower body 11 rotatably supports the upper rotating body 13. The lower body 11 illustrated in Fig. 1 is a lower traveling body that can travel on a traveling surface (such as the ground) and includes a traveling device including a pair of left and right crawlers. The traveling device may include a plurality of wheels instead of the pair of crawlers.

[0013] The upper rotating body 13 is rotatably mounted on the lower body 11. The upper rotating body 13 includes a cab 13c, and the cab 13c allows an operator to ride in the cab 13c and operate the work machine 10.

[0014] The attachment 15 is a working device capable of performing a work operation. The attachment 15 is attached to the machine body 10a, or in this embodiment, the upper rotating body 13. The attachment 15 illustrated in Fig. 1 includes a boom 15a, an arm 15b, and a tip attachment 15c.

[0015] The boom 15a has a base end connected to the upper rotating body 13 so as to be able to rise and fall, i.e., to be able to rotate about an axis in the left-right direction, and a tip end on the opposite side. The arm 15b has a base end connected to the tip end of the boom 15a so as to be able to rotate about an axis in the left-right direction, and a tip end on the opposite side.

[0016] The tip attachment 15c constitutes the tip of the attachment 15. The tip attachment 15c is connected to the tip of the arm 15b so as to be rotatable about a left-right axis. The tip attachment 15c illustrated in FIG. 1 is a bucket capable of scooping captured material and digging. The tip attachment 15c may alternatively be a device for clamping captured material (such as a grapple or nibbler), a device for crushing captured material (such as a breaker), or a magnet for attracting captured material, including metal. The captured material captured by the tip attachment 15c is a work target that is the object of work performed by the work machine 10. The captured material may be soil, stone, wood, metal, resin, waste, or a structure (such as a block).

[0017] The attachment 15 includes a predetermined control object CT. The control object CT is a part that is to be controlled to move along a target path PA, which will be described later. The control object CT illustrated in FIG. 1 is the tip 15s of the bucket, which is the tip attachment 15c. However, the control object CT can be set arbitrarily, and may be the base end of the tip attachment 15c, in other words, the tip of the arm 15b.

[0018] The multiple actuators are arranged to move multiple movable members included in the work machine 10, respectively. Each of the multiple actuators is a hydraulic actuator. Alternatively, the multiple actuators may include electric actuators. The multiple actuators 30 shown in Figure 1 include a pair of travel motors 31, a swing motor 33, a boom cylinder 35a, an arm cylinder 35b, and a tip attachment cylinder 35c.

[0019] Each of the pair of travel motors 31 and the swing motor is a hydraulic motor. The pair of travel motors 31 respectively drive the pair of crawlers, thereby causing the lower body 11 to travel. The swing motor 33 causes the upper swing body 13 to swing relative to the lower body 11. Each of the pair of travel motors 31 and the swing motor may be an electric motor.

[0020] The boom cylinder 35a, the arm cylinder 35b, and the tip attachment cylinder 35c are each a hydraulic cylinder that extends and retracts. The boom cylinder 35a is arranged to raise and lower the boom 15a relative to the upper rotating body 13, i.e., to rotate it about an axis in the left-right direction. The arm cylinder 35b is arranged to rotate the arm 15b relative to the boom 15a about an axis in the left-right direction. The tip attachment cylinder 35c is arranged to rotate the tip attachment 15c relative to the arm 15b about an axis in the left-right direction. If the tip attachment 15c itself includes a movable member, such as a device for clamping an object, the multiple actuators may further include an actuator for moving the movable member included in the tip attachment 15c.

[0021] 2 drives each of the plurality of actuators. The actuator driving unit 17 includes a hydraulic circuit 20, which supplies hydraulic pressure to each of the plurality of actuators to drive the actuator.

[0022] As shown in FIG. 3, the hydraulic circuit 20 includes a hydraulic oil tank 20 t, a pump 21 , a pump displacement control unit 23 , and a plurality of control valves 25 .

[0023] The hydraulic oil tank 20t is a tank (container) for storing hydraulic oil.

[0024] The pump 21 is driven by the engine 39 to suck hydraulic oil from the hydraulic oil tank 20t and supply it to each of the plurality of actuators. The hydraulic circuit 20 may include a plurality of pumps 21. The pump 21 shown in Figure 3 has a variable displacement.

[0025] The pump displacement control unit 23 controls the displacement of the pump 21 in accordance with a displacement command input to the pump displacement control unit 23. The displacement command may be a pilot oil pressure or an electric signal given to a regulator constituting the pump displacement control unit 23. The pump displacement control unit 23 controls the displacement of the pump 21 by, for example, changing the tilt angle of the pump 21.

[0026] The plurality of control valves 25 are respectively interposed between the pump 21 and the plurality of actuators, and operate to open and close so as to enable control of the movements of the plurality of actuators. Each of the control valves 25 switches the direction of movement (e.g., rotational direction or extension / contraction direction) of a corresponding actuator, which is an actuator among the plurality of actuators connected to that control valve 25, by switching the direction of flow of hydraulic oil supplied to that corresponding actuator. The control valve 25 changes the operating speed of that corresponding actuator by changing the flow rate of hydraulic oil supplied to that corresponding actuator.

[0027] Each of the control valves 25 is configured as a pilot-operated hydraulic change-over valve, and opens and closes in response to a pilot pressure input to the control valve 25 from a pilot hydraulic source (not shown). A solenoid valve (not shown) is interposed between each of the plurality of control valves 25 and the pilot hydraulic source. Each of the solenoid valves opens to an opening corresponding to an electrical signal, i.e., a pilot pressure command signal, input to the solenoid valve, thereby allowing a pilot pressure corresponding to the opening to be input to the control valve 25. In other words, the solenoid valve controls the opening operation of the control valve 25 by inputting the pilot pressure command signal to the solenoid valve, thereby enabling control of the movement of the corresponding actuator corresponding to the control valve 25.

[0028] When the plurality of actuators include an electric actuator, the actuator driving unit 17 may include an electric circuit for driving the electric actuator. The electric circuit is configured to supply the electric actuator with power corresponding to a target speed of the electric actuator.

[0029] The engine 39 is the power source of the work machine 10, and enables each of the plurality of actuators to be driven by driving the pump 21 and causing the pump 21 to discharge hydraulic oil. If the plurality of actuators includes an electric actuator, the engine 39 may drive a generator. The power source of the work machine 10 is not limited to the engine 39, and may be, for example, a combination of an electric motor for driving the pump 21 and a power source that serves as the power source for the electric motor.

[0030] The work machine 10 is equipped with a plurality of elements shown in FIG. 2, namely, a detection unit 40, an input unit 60, a controller 70, and an output unit 80.

[0031] The detection unit 40 includes a plurality of detectors for detecting the state of the work machine 10. The plurality of detectors may include a detector disposed outside the work machine 10. Specifically, the detection unit 40 includes a pump pressure detector 40p, a position detector 41, an imaging device 43, and an attitude detection unit 50.

[0032] The pump pressure detector 40p detects the pressure of the hydraulic oil discharged from the pump 21 shown in FIG. 3 , i.e., the pump pressure. The pump pressure detector 40p may be provided either inside or outside the pump 21. For example, the pump pressure detector 40p may be connected to an oil passage, such as a pipe, through which the hydraulic oil discharged from the pump 21 flows, or may be provided in a portion of the oil passage through which the hydraulic oil discharged from the pump 21 flows, where the hydraulic oil pressure is the same or approximately the same as the hydraulic oil pressure at the discharge port (outlet) of the pump 21. The pump pressure detector 40p may be provided between the pump 21 and the plurality of control valves 25. When the hydraulic circuit 20 includes a plurality of pumps 21, the pump pressure detector 40p is provided for each of the plurality of pumps 21.

[0033] The position detector 41 detects the position of a measurement target portion set on the work machine 10. The position detector 41 illustrated in FIG. 1 detects the position of a specific portion of the upper rotating body 13. Alternatively, the position detector 41 may detect the position of a specific portion of the attachment 15. The position detector 41 may detect the position using electromagnetic waves such as light or radio waves, or may use a satellite positioning system such as a global navigation satellite system (GNSS). The position detector 41 may also use a system including a (terrestrial) transmitter and receiver that does not use a satellite, such as a total station. The position detector 41 may further detect the direction (orientation) of the measurement target.

[0034] The detection unit 40 may include a direction detector in addition to the position detector 41. The direction detector may detect the orientation of the measurement object using geomagnetism. The position detector 41 may include a plurality of position detection sensors that acquire position information, and a calculator that calculates the position and direction of the measurement object based on the position information acquired by each of the plurality of position detection sensors.

[0035] The imaging device 43 captures an image of an object to be imaged. The object to be imaged may include the work machine 10, or the surroundings of the work machine 10. The imaging device 43 may include a device that generates a two-dimensional image, such as a monocular camera, or a device that generates a three-dimensional image (distance image) that further includes information about the position in the depth direction, such as a stereo camera. The imaging device 43 may be of a passive type or an active type. The imaging device 43 may acquire three-dimensional information about the object to be imaged by irradiating the object with waves, such as electromagnetic waves, and detecting the reflected waves. The imaging device 43 may include a time-of-flight (TOF) sensor that irradiates waves and detects the distance based on the time from the irradiation to the return of the reflected waves, or may include a sensor that detects the distance based on the frequency of the reflected waves. The imaging device 43 may include a device that acquires three-dimensional information using light such as laser light, such as a LiDAR (Light Detection and Ranging). The imaging device 43 may also include a device that acquires three-dimensional information using radio waves, such as a millimeter-wave radar. The imaging device 43 may also acquire three-dimensional information of an imaging target based on a combination of a three-dimensional image (distance image) and a two-dimensional image.

[0036] The attitude detection unit 50 detects the attitude of the work machine 10. The attitude detection unit 50 includes at least one detector. The attitude detection unit 50 may include a detector, such as a rotary encoder, that detects angle information of a second element relative to a first element among multiple elements included in the work machine 10. The attitude detection unit 50 may include a stroke sensor that detects the stroke of the hydraulic cylinder that moves the attachment 15, such as the boom cylinder 35a. The attitude detection unit 50 may include an inclination sensor that detects the angle of a specific element relative to the horizontal direction, i.e., the inclination angle. The attitude detection unit 50 may include an angular velocity sensor, such as a gyro sensor, that detects the angular velocity of a specific element relative to the work site, or an acceleration sensor that detects the acceleration of a specific element relative to the work site. The control attitude detection unit 50 may include a device that measures the inertia of a specific element. The attitude detection unit 50 may identify the attitude of the work machine 10 based on position information detected by the position detector 41. The attitude detection unit 50 may identify the attitude of the work machine 10 based on two-dimensional images and / or three-dimensional images acquired by the imaging device 43 .

[0037] The posture detection unit 50 according to this embodiment includes a plurality of detectors shown in FIG. 1, namely, a reference position detector 51, a tilt detector 52, a rotation detector 53, a boom detector 55 a, an arm detector 55 b, and a tip attachment detector 55 c.

[0038] The reference position detector 51 detects a reference position, which is the position of a reference part relative to the work site, and the orientation of the reference part. The reference part is a part that serves as a reference in the work machine 10, and for example, a specific part of the upper rotating body 13 or the lower body 11 is selected as the reference part. More specifically, the reference part may be a part of the boom 15a that is connected to the upper rotating body 13, i.e., a boom foot, or a specific part located on the central axis of rotation of the upper rotating body 13 relative to the lower body 11. The reference position detector 51 may identify the position and orientation of the reference part relative to the work site based on information acquired by at least one of the position detector 41 and the imaging device 43, for example. In the example shown in FIG. 1 , the reference position detector 51 and the position detector 41 use a positioning system including GNSS, and the positions of the GNSS antennas are representatively shown as the positions of the reference position detector 51 and the position detector 41.

[0039] The inclination detector 52 detects the inclination of the work machine 10 with respect to the horizontal direction. The inclination detector 52 may identify the inclination of the work machine 10 based on information acquired by at least one inclination sensor, such as a gyro sensor, an acceleration sensor, or an inertial measurement unit, or may detect the inclination of the work machine 10 with respect to the horizontal direction based on information acquired by at least one of the position detector 41 and the imaging device 43.

[0040] The rotation detector 53 detects rotation information, which is information related to the rotation of the upper rotating body 13 relative to the lower body 11, such as at least one of a rotation angle, a rotation angular velocity, and a rotation angular acceleration. The rotation detector 53 may include, for example, an angle sensor attached to a rotation central axis that is the center of rotation of the upper rotating body 13 relative to the lower body 11 or a member supporting the axis, such as a rotation bearing, and may identify the rotation information based on information about the angle detected by the angle sensor. The rotation detector 53 may identify the rotation information based on information acquired by at least one of the position detector 41 and the imaging device 43.

[0041] The boom detector 55a detects the attitude of the boom 15a. The boom detector 55a detects at least one of a boom angle, a boom angular velocity, and a boom angular acceleration. The boom angle is the angle of the boom 15a with respect to the horizontal direction, i.e., the tilt angle, or the angle of the boom 15a with respect to the upper rotating structure 13, i.e., the hoisting angle. The boom angular velocity is the angular velocity of the boom 15a with respect to the upper rotating structure 13, and the boom angular acceleration is the angular acceleration of the boom 15a with respect to the upper rotating structure 13. The boom detector 55a may be configured to identify the attitude of the boom 15a based on information acquired by at least one of the position detector 41 and the imaging device 43.

[0042] The arm detector 55b detects the posture of the arm 15b. The arm detector 55b detects at least one of an arm angle, an arm angular velocity, and an arm angular acceleration. The arm angle is the angle of the arm 15b with respect to the horizontal direction, i.e., the tilt angle, or the angle of the arm 15b with respect to the boom 15a, the arm angular velocity is the angular velocity of the arm 15b with respect to the boom 15a, and the arm angular acceleration is the angular acceleration of the arm 15b with respect to the boom 15a. The arm detector 55b may be configured to identify the posture of the arm 15b based on information acquired by at least one of the position detector 41 and the imaging device 43.

[0043] The end attachment detector 55c detects the attitude of the end attachment 15c. The end attachment detector 55c detects at least one of a end attachment angle, a end attachment angular velocity, and a end attachment angular acceleration. The end attachment angle is the angle of the end attachment 15c with respect to the horizontal direction, i.e., the tilt angle, or the angle of the end attachment 15c with respect to the arm 15b. The end attachment angular velocity is the angular velocity of the end attachment 15c with respect to the arm 15b, and the end attachment angular acceleration is the angular acceleration of the end attachment 15c with respect to the arm 15b. The end attachment detector 55c may identify the attitude of the end attachment 15c based on information acquired by at least one of the position detector 41 and the imaging device 43.

[0044] The input unit 60 is an input device for inputting necessary information to the controller 70. The input unit 60 is configured to allow an operator to operate the input unit 60, and to generate and output a signal corresponding to the operation. The input unit 60 includes, for example, at least a part of a touch panel, a mouse, a keyboard, and a switch. The input unit 60 is included, for example, in at least a part of a tablet, a smartphone, and a personal computer. The input unit 60 may be provided in an appropriate location on the work machine 10, for example, in the operator's cab 13c, or may be provided in a remote control device for remotely operating the work machine 10.

[0045] As shown in Fig. 2, the input unit 60 includes the operation unit 61 and the automatic control switch 63. The operation unit 61 allows an operation to be applied to the operation unit 61 to move the work machine 10. The operation unit 61 includes, for example, at least one of an operation lever and an operation pedal. The automatic control switch 63 allows an automatic control selection operation to be applied to the automatic control switch 63. The automatic control selection operation is an operation by which the operator selects whether or not to perform automatic control of the work machine 10. Details of automatic control will be described later.

[0046] The controller 70 is configured by a computer and includes an interface that enables input and output of signals, a calculation unit that performs necessary calculation processing, and a storage unit that stores information. The functions of the controller 70 are realized by the calculation unit executing a program stored in the storage unit. The controller 70 may be connected to other devices via wireless or wired communication. Multiple components included in the controller 70 may be connected to each other via wireless or wired communication. Information is input to the controller 70 illustrated in FIG. 2 from the detection unit 40 and the input unit 60.

[0047] The controller 70 controls each of the plurality of actuators. Specifically, the controller 70 generates commands (signals) for operating each of the plurality of actuators and inputs the commands (signals) to the actuator driving unit 17. The controller 70 may be mounted on the work machine 10 or may be arranged externally to the work machine 10. The controller 70 may be arranged in a distributed manner in a plurality of parts, i.e., may form a distributed system.

[0048] The controller 70 constitutes a control system together with at least one target actuator included in the plurality of actuators. The target actuator is an actuator among the plurality of actuators that contributes to the movement of the control target CT.

[0049] The controller 70 illustrated in FIG. 2 includes an automatic control controller 71 and a vehicle body controller 73 .

[0050] The automatic control controller 71 is an automatic driving controller that performs processing related to automatic driving. The automatic control controller 71 automatically controls the drive of the multiple actuators so as to move the work machine 10 in accordance with a work plan, which will be described later. Specifically, the automatic control controller 71 inputs commands to the actuator drive unit 17 via the vehicle controller 73 so as to move the work machine 10 in accordance with the work plan. The automatic control controller 71 controls the movement of the work machine 10 based on the attitude detected by the attitude detection unit 50.

[0051] Specifically, the automatic controller 71 includes a plurality of functions shown in FIG. 2, namely, a detected information processing section 71a, a work plan setting section 71b, a work plan changing section 71c, and a target command calculation section 71d.

[0052] The detected information processing section 71a takes in information input from the detecting section 40 and the automatic control switch 63 of the input section 60 and processes the information.

[0053] The work plan setting unit 71b sets the work plan based on the information processed by the detected information processing unit 71a.

[0054] The work plan change unit 71c changes the work plan as necessary. The work plan change unit 71c functions as a work plan change processing unit based on equipment capacity. In other words, the work plan change unit 71c has the function of changing the work plan based on the capacity of the equipment included in the work machine 10. The change to the work plan made by the work plan change unit 71c includes a target speed change that changes the target speed V shown in FIG. 1 and described below to a revised target speed Vrv.

[0055] The target command calculation unit 71d calculates a target command to be input to the vehicle body controller 73, and inputs the target command to the vehicle body controller 73. The target command includes a command regarding the target speed V. That is, the target command calculation unit 71d functions as a target speed command calculation unit.

[0056] The vehicle body controller 73 controls the movement of the work machine 10 based on commands input from the operation unit 61 and the automatic control controller 71. Specifically, the vehicle body controller 73 includes a plurality of functions shown in Fig. 2, namely, a target command processing unit 73a, a drive command calculation unit 73b, and an output limitation processing unit 73c.

[0057] The target command processing unit 73a receives and processes the target command input from the automatic controller 71. The target command processing unit 73a functions as a target speed command processing unit that processes a command regarding the target speed V.

[0058] The drive command calculation unit 73b calculates a drive command to be input to the actuator drive unit 17. Specifically, since each of the multiple actuators according to this embodiment is a hydraulic actuator, the drive command calculation unit 73b calculates, as the drive command, a command to be input to the hydraulic circuit 20 that drives each of the multiple actuators. More specifically, the drive command calculation unit 73b functions as a solenoid valve command calculation unit that calculates commands to be input to the multiple solenoid valves included in the hydraulic circuit 20. The hydraulic circuit 20 is configured to be able to change the distribution of the flow rate of hydraulic oil discharged from the pump 21 to the multiple actuators in accordance with the target speed V of each of the multiple actuators. If each of the multiple actuators is an electric actuator operated by electricity, the drive command calculation unit 73b calculates a command to control an electric circuit that drives the multiple actuators, i.e., a circuit included in the actuator drive unit 17.

[0059] The output limiting processing unit 73c performs output limiting control, which is control for limiting the output of each of the plurality of actuators. The output limiting control will be described in detail later.

[0060] The output unit 80 is a device that outputs information. The output unit 80 outputs information based on a signal input from the controller 70. The output unit 80 outputs information to an operator, specifically, notifies or instructs the operator. The output unit 80 may output any of light, sound, and vibration for display. When outputting light, the output unit 80 may include a display unit that performs display, such as a monitor. The output unit 80 may be provided in, for example, a tablet, a smartphone, or a personal computer. The output unit 80 may be provided in, for example, the operator's cab 13c, or in a remote control device that remotely controls the work machine 10. For example, the output unit 80 may output the details of work performed by automatic control of the work machine 10. The output unit 80 may output information about the target speed change.

[0061] The work machine 10 is a machine that utilizes information and communication technology (ICT), for example, an ICT construction machine.

[0062] The controller 70 performs machine control (MC) to control the movement of the work machine 10. In other words, it enables the work machine 10 to be operated semi-automatically. Specifically, the controller 70 stores a work plan. When the operator inputs a command for an element to be operated (e.g., the boom 15a) included in the attachment 15 to the operation unit 61, the controller 70 automatically controls the operation of elements of the attachment 15 other than the element to be operated (e.g., the arm 15b and the tip attachment 15c) so that the work machine 10 moves in accordance with the work plan. In the machine control, the controller 70 controls the operation of the work machine 10 based on information detected by the attitude detection unit 50, thereby performing semi-automatic operation so that the work machine 10 moves in accordance with the work plan.

[0063] Alternatively, the work machine 10 may be operated by automatic driving. Specifically, the controller 70 may control the operation of the work machine 10 based on the information detected by the attitude detection unit 50 so that the work machine 10 moves automatically in accordance with a work plan.

[0064] The work plan setting unit 71b of the controller 70 shown in Figure 2 sets the work plan. The work plan is information related to the goals of the work to be performed by the work machine 10. The work plan includes information related to the goals of the movement of the attachment 15. The work plan may also include information related to the goals of the traveling operation of the work machine 10.

[0065] The work plan setting unit 71b sets a target trajectory, which is an example of the work plan. The target trajectory includes information on a target path PA shown in FIG.

[0066] The target route PA is a route along which the control target CT is to be moved. Alternatively, the target route PA may be a portion determined for the work machine 10 when the work machine 10 is traveling, i.e., a route along which the control target should move. The target route PA includes, for example, information (coordinates) relating to target point positions, which are the respective positions of a plurality of target points P1 to PN (N is a natural number of 2 or greater) lined up along the target route PA, and information relating to the order of the plurality of target points P1 to PN.

[0067] The target trajectory includes time information in addition to information about the target path PA. The time information may be information about a time between two points, or information about a target arrival time. The time between two points is a target value for the time it takes for the control target CT to move between two adjacent (sequential) target points among the plurality of target points P1 to PN. The target arrival times are target values ​​for the time it takes for the control target CT to arrive at each of the plurality of target points P1 to PN.

[0068] In this way, the target trajectory includes information about the target point position and the time information, and thereby substantially includes information about the target velocity V of the control target CT. As shown in FIG. 4, the target velocity V can be adjusted by adjusting the time information. The target trajectory is not limited to one that indirectly includes information about the target velocity V by including information about the target point position and the time information, but may also directly include information about the target velocity V. Furthermore, the target velocity V may be a target value for the velocity of the control target CT itself, or a target value for the operating velocity of an actuator that moves the control target CT among the multiple actuators.

[0069] Parameters representing positions related to the work plan, specifically position parameters representing the target point positions, can be set in various ways. Parameter coordinates, which are coordinates indicating the position parameters, can be set arbitrarily. Specifically, the parameter coordinates may be absolute coordinates based on the work site, or machine coordinates based on the work machine 10. For example, the origin of the machine coordinates may be set to a portion of the boom 15a connected to the upper rotating body 13, such as a boom foot pin, or may be set to a position on the central axis of rotation of the upper rotating body 13 relative to the lower main body 11. Specifically, the work plan may include information on at least one of the upper rotating body fore-and-aft direction, which is the fore-and-aft direction of the upper rotating body 13, the up-and-down direction, the rotation angle of the upper rotating body 13 relative to the lower main body 11, and the tilt angle (attitude) of the tip attachment 15c. The position parameters may include the positions of the multiple actuators for moving the work machine 10, such as the stroke position of a hydraulic cylinder or the rotation angle of a hydraulic motor.

[0070] The work plan may be set by an operator operating the work machine 10 and performing teaching, or may be set manually by the operator providing appropriate operations to the input unit 60. Alternatively, the work plan may be set automatically by the controller 70. For example, the work plan may be set automatically by the work plan setting unit 71b of the controller 70 based on information detected by the detection unit 40 (such as information about obstacles). Alternatively, the work plan may be stored in the controller 70 before the work machine 10 is shipped.

[0071] The work plan may be corrected before the target speed is changed. For example, the work plan may be corrected manually by an operator providing an appropriate operation to the input unit 60, or may be automatically corrected by, for example, the work plan change unit 71 c of the controller 70 based on information detected by the detection unit 40, such as information about an obstacle.

[0072] FIG. 4 is a graph showing an example of information related to the work plan, illustrating the relationship between the target point positions and time in the work plan. Specifically, the vertical axis of the graph represents coordinates corresponding to multiple coordinate axes (e.g., X-axis, Y-axis, Z-axis, etc.) of the multiple target points P1 to PN of the control target CT of the attachment 15 shown in FIG. 1 . The horizontal axis of the graph represents the time in the work plan. Each of multiple times t1, t2, t3, and t4 arranged along the horizontal axis represents a target value, i.e., a target arrival time, for the time at which the control target CT should reach each of the target points P1, P2, P3, and P4 included in the multiple target points. Time t4a, which is later than time t4, represents the post-change time of time t4 corresponding to the change of the target speed V of the control target CT from time t3 to time t4 to the revised target speed Vrv due to the target speed change, i.e., a revised target arrival time corresponding to the target arrival time t4.

[0073] The target speed change is performed by the controller 70. The target speed change is performed by changing only the target speed V to a revised target speed Vrv without changing the target path PA, out of the target path PA and the target speed V included in the target trajectory. In this embodiment, the target speed change includes a target speed change based on equipment capability and a target speed change corresponding to output limit control.

[0074] The target speed change based on the equipment capability is a change in the target speed V to bring the required capacity Ar shown in FIG. 5 into the actuator capacity range Ra. The required capacity Ar is the capacity required of the target actuator to move the control target CT along the target trajectory, and as described above, the target actuator is one of the multiple actuators that contributes to the movement of the control target CT. The actuator capacity range Ra is the range of capacity of the target actuator. The target speed change based on the equipment capability is performed when the required capacity Ar falls outside the actuator capacity range Ra. If the required capacity Ar falls outside the actuator capacity range Ra, the target actuator cannot move the control target CT along the target trajectory, i.e., the target trajectory cannot be realized. For example, if the required capacity Ar exceeds the maximum capacity of the target actuator, the control target CT cannot follow the target trajectory. Conversely, if the required capacity Ar falls below the minimum capacity of the target actuator, the target trajectory cannot be realized. Furthermore, even if the required capacity Ar is greater than the minimum capacity and less than the maximum capacity of the target actuator, if it is smaller than the capacity range in which the capacity of the target actuator can be fully utilized, the efficiency of work by the work machine 10 will be reduced.

[0075] In order to solve the above-mentioned problems, the work plan change unit 71c of the controller 70 shown in FIG. 2 changes the target speed V to a revised target speed Vrv so that the required capacity Ar shown in FIG. 5 falls within the actuator capacity range Ra.

[0076] The controller 70 sets the actuator capability range Ra. The capability of the target actuator depends not only on the capability of the target actuator itself, but also on the capability of the actuator driving device that drives the target actuator. Therefore, the controller 70 sets the actuator capability range Ra based on both the capability of the target actuator itself and the capability of the actuator driving device. The actuator capability range Ra may be stored in the controller 70 in advance before the work machine 10 is shipped.

[0077] When the target actuator is a hydraulic actuator as in this embodiment, the capacity of the actuator driving device includes the capacity of the pump 21 for supplying hydraulic oil to the target actuator and the capacity of the engine 39 for driving the pump 21. The capacity of the pump 21 is defined, for example, by the minimum flow rate, maximum flow rate, or preferred flow rate range of the pump 21. The capacity of the engine 39 is defined, for example, by the minimum output, maximum output, or preferred output range of the engine 39. When the target actuator is an electric actuator, the capacity of the actuator driving device includes, for example, the capacity of a power source (minimum output, maximum output, preferred output range, etc.).

[0078] The factors that determine the capacity related to the actuator capacity range Ra may include any of the capacity of the target actuator itself, the output (e.g., torque, thrust, etc.) of the actuator driving device, acceleration, speed, and required time, as will be described in detail later.

[0079] The actuator capability range Ra may be the maximum range of capability in which the target actuator can be used, i.e., the range from the minimum capability to the maximum capability of the target actuator, or it may be a more limited range, for example, a preferred range in which it is preferable to use the target actuator. The "preferable range" can be determined from various perspectives. For example, the preferred range may be set taking into consideration the workability of the work machine 10, or the energy consumed by the work machine 10.

[0080] The actuator capability range Ra may be stored in advance in a storage unit (not shown) of the controller 70, or may be determined based on information input to the controller 70 via the input unit 60, i.e., information manually input by an operator. Alternatively, the actuator capability range Ra may be calculated by the controller 70 based on information relating to the capability of the actuator driving device or other information, as will be described later.

[0081] The actuator capability range Ra may include a range of output of the target actuator, for example, a range of torque or thrust. In this case, the minimum value of the actuator capability range Ra may be 0 or a value greater than 0. If the target actuator is a hydraulic actuator as in this embodiment, the minimum value of the actuator capability range Ra may be set based on the output of the target actuator when hydraulic oil is supplied from the pump 21 to the target actuator at a minimum flow rate. Conversely, the maximum value of the actuator capability range Ra may be set based on the maximum output (for example, maximum torque or maximum thrust) that the target actuator can output, or may be the upper limit of a preferred range of the output of the target actuator.

[0082] The actuator capability range Ra may include a range of accelerations. For example, the actuator capability range Ra may include a range of accelerations of the control target CT moved by the target actuator. In this case, the minimum value of the actuator capability range Ra may be 0 or a value greater than 0. Conversely, the maximum value of the actuator capability range Ra may be an output maximum acceleration, which is the maximum acceleration at which the control target CT can be moved by the target actuator. Alternatively, the actuator capability range Ra may be a preferred range of accelerations of the control target CT moved by the target actuator.

[0083] For example, the controller 70 may calculate the actuator capability range Ra (e.g., maximum output acceleration) regarding the acceleration based on inertia information, which is information regarding the inertia of the target movable member, which is a movable member including the control object CT, and information regarding the maximum output of the target actuator.

[0084] When the target movable member is rotatable, the inertia information includes, for example, information about the moment of inertia of the target movable member. When the target movable member is translatory, the inertia information includes, for example, information about the inertial mass of the movable member. When the target actuator is the rotation motor 33 and the target movable member is the upper rotating body 13 and the attachment 15, the inertia information includes, for example, the moment of inertia of the upper rotating body 13 and the attachment 15, based on the rotation center of the upper rotating body 13 relative to the lower body 11.

[0085] When at least a part of the target movable member is included in the mechanical body 10a and the mechanical body 10a is tilted relative to the horizontal direction, the inertial information preferably includes tilt information about the tilt of the mechanical body 10a, the tilt information including information about the direction of the tilt and information about the angle of the tilt.

[0086] When at least a portion of the target movable member is included in the attachment 15, it is preferable that the inertia information is information that takes into account information about the inertia of the object captured by the attachment 15.

[0087] The actuator capability range Ra may include a range of speeds. Specifically, the actuator capability range Ra may include a range of speeds of the control target CT moved by the target actuator 30. For example, the controller 70 may calculate the actuator capability range Ra for the speed based on the output of the target actuator and inertia information of the target movable member, similar to the actuator capability range Ra for the acceleration.

[0088] The actuator capability range Ra may include a range of required time. Specifically, the actuator capability range Ra may include a range of the length of time required for the target actuator to move the control target CT to a specific position. The actuator capability range Ra may also include a range of the length of time required for the target actuator to change the velocity of the control target CT to a predetermined velocity, or a range of the length of time required for the target actuator to change the velocity of the control target CT to a predetermined acceleration. The controller 70 may calculate the actuator capability range Ra for the required time based on the output of the target actuator and inertia information of the target movable member, similar to the actuator capability range Ra for the acceleration.

[0089] The controller 70 calculates the required capacity Ar to change the target velocity V so that the required capacity Ar falls within the actuator capacity range Ra. As described above, the required capacity Ar is the capacity required of the target actuator 30 to move the controlled object CT according to the target trajectory. In other words, it is the capacity of the target actuator that is expected to be exerted when the target actuator moves the controlled object CT according to the target trajectory. The required capacity Ar may be any of the output of the target actuator, the acceleration of the controlled object CT, the velocity of the controlled object CT, and the required time, similar to the capacity related to the actuator capacity range Ra. For example, the required capacity Ar may be the acceleration of the controlled object CT that is required for the target actuator to move the controlled object CT according to the target trajectory, i.e., the required acceleration. The required acceleration is the acceleration of the controlled object CT that is expected when the target actuator moves the controlled object CT according to the target trajectory. The actuator capacity range Ra and the required capacity Ar need to be able to be compared with each other. For example, if the actuator capacity range Ra is the range of acceleration, the required capacity Ar also needs to be expressed in terms of acceleration.

[0090] The manner in which the controller 70 calculates the required capacity Ar is not limited. The controller 70 may calculate the required capacity Ar based on information included in the target trajectory. For example, the controller 70 may calculate the required capacity Ar based on information about the target velocity V, such as information about the relationship between the target point positions and the time information, or may calculate the required capacity Ar based on information about the target path PA, more specifically, information about the positions of the target points. Alternatively, the controller 70 may calculate the required capacity Ar based on both information about the target trajectory and inertia information about the control target CT.

[0091] As described above, when the required capacity Ar is outside the actuator capacity range Ra, the controller 70 performs the target speed change to change the target speed V to a revised target speed Vrv without changing the target path PA. The revised target speed is determined so that the revised required capacity Arv, which is the required capacity Ar corresponding to the revised target speed Vrv, falls within the actuator capacity range Ra.

[0092] Specifically, when the required capacity Ar is greater than the actuator capacity range Ra, the controller 70 changes the target speed V to the revised target speed Vrv which is lower than the target speed V so that the revised required capacity Arv falls within the actuator capacity range Ra. For example, the work plan change unit 71c of the controller 70 reduces the target speed V so that the revised required capacity Arv becomes a maximum allowable value set based on the maximum value of the actuator capacity range Ra. The maximum allowable value may be a value equal to the maximum value or a value smaller than the maximum value.

[0093] When the required capacity Ar is smaller than the actuator capacity range Ra, the controller 70 changes the target speed V to a revised target speed Vrv that is higher than the target speed V so that the revised required capacity Arv falls within the actuator capacity range Ra. For example, the controller 70 increases the target speed V so that the revised required capacity Ar becomes a minimum allowable value set based on the minimum value of the actuator capacity range Ra. The minimum allowable value may be a value equal to the minimum value or a value greater than the minimum value.

[0094] When the required capacity Ar is specified by the required acceleration and the maximum value of the actuator capacity range Ra is the maximum output acceleration, if the required acceleration is greater than the maximum output acceleration, the capacity of the target actuator is insufficient to move the control target CT along the target trajectory, i.e., the target trajectory cannot be realized. To enable such movement of the control target CT along the target trajectory, the controller 70 changes the target velocity V to the revised target velocity Vrv so that the revised required acceleration is equal to or less than the maximum output acceleration. The revised required acceleration is the acceleration required to realize the revised target velocity Vrv. The controller 70 calculates the revised acceleration, which is the acceleration after the target velocity change, based on, for example, output information of the target actuator. The controller 70 may further calculate the revised acceleration based on inertia information of the control target CT. The controller 70 calculates the revised target velocity Vrv based on the revised acceleration. Such a change in the target speed makes it possible to move the control object TC along the target path PA of the target trajectory using the capabilities of the equipment of the work machine 10.

[0095] In this embodiment, the controller 70 changes the target speed in accordance with the output limit control in addition to changing the target speed based on the equipment capability.

[0096] The output limiting control is performed by an output limiting processing unit 73c of the vehicle body controller 73 in the controller 70. The output limiting control is control that limits the output of the target actuator. The output limiting control is control that limits the output of the target actuator in accordance with the capacity of the actuator driving device, and is control that performs output limiting due to the influence of disturbances. The output limiting control is performed immediately (in real time) in accordance with the status of the working machine 10 during operation.

[0097] In this embodiment, the target actuator, which is a hydraulic actuator, is driven by hydraulic fluid supplied from the pump 21, and the pump 21 is driven by the engine 39. Therefore, as the output limiting control, the output limiting processing unit 73c performs control to limit the output of the pump 21 so as to prevent the output of the pump 21 from exceeding a set value (e.g., maximum output) of the output of the engine 39. Specifically, the output limiting processing unit 73c performs PQ control, which is an example of the output limiting control. The PQ control is control to limit the flow rate of hydraulic fluid discharged from the pump 21, i.e., the pump flow rate, in accordance with the pressure of the hydraulic fluid discharged from the pump 21, i.e., the pump pressure. The pump pressure is detected by the pump pressure detector 40p. The pump flow rate is controlled by the pump displacement control unit 23. The output limiting processing unit 73c limits the flow rate of hydraulic fluid supplied from the pump 21 to the target actuator through the PQ control, thereby limiting the speed (output) of the target actuator. When the target actuator is an electric actuator, the output limiting processing unit 73c performs the output limiting control by limiting the output of the target actuator in accordance with the output (electric power) of a power source or the like.

[0098] The work plan change unit 71c of the controller 70 changes the target speed V based on the output of the target actuator that is changed in response to the output limit control. In this case, as with the target speed change based on equipment capability described above, the controller 70 changes only the target speed V to a revised target speed Vc without changing the target path PA on the target trajectory. Because the output limit control is performed immediately (in real time) in response to the status of the working machine 10 during operation (for example, pump pressure, etc.) as described above, the target speed change corresponding to the output limit control is also performed immediately in response to the output limit control.

[0099] For example, the output limiting processing unit 73c of the vehicle body controller 73 generates a revised target speed command for changing the target speed corresponding to the output limiting control and inputs the revised target speed command to the work plan changing unit 71c of the automatic control controller 71. Specifically, the vehicle body controller 73 immediately performs output limiting control in accordance with the status of the target actuator that is moving the control target CT according to the target trajectory. Specifically, the vehicle body controller 73 inputs (feeds back) the revised target speed command for changing the target speed corresponding to the output limiting control to the work plan changing unit 71c. The work plan changing unit 71c changes the target speed V of the target actuator to a revised target speed Vc based on the revised target speed command. Specifically, the work plan changing unit 71c reduces the target speed V.

[0100] As described above, the controller 70 changes the target speed based on the equipment capabilities and in response to output limit control. Specifically, as shown in FIG. 4 , the controller 70 changes the target speed V by changing the time information on the target trajectory. More specifically, the controller 70 may change the target speed V by lengthening or shortening the time between two adjacent target points among the plurality of target points P1 to PN. Alternatively, the controller 70 may change the target speed V by delaying or advancing the target time at which the control object CT passes through each target point, i.e., the target arrival time. In other words, the controller 70 may calculate a revised target arrival time. If the target trajectory includes information on the target speed V itself, the controller 70 may directly change the target speed V. If the target speed V is expressed by multiple coordinates, such as an X coordinate, a Y coordinate, and a Z coordinate, the controller 70 calculates each coordinate of the revised target speed Vc.

[0101] The controller 70 can maintain the target path PA appropriately by changing the target velocity V to the revised target velocity Vc without changing the target path PA on the target trajectory. That is, if the target path PA before the target velocity change is set appropriately, the path of the target CT moved by the target actuator according to the target trajectory after the target velocity change will also be an appropriate path. For example, if the target path PA before the target velocity change is set so as to prevent the control target CT from interfering with an obstacle or the like, the control target TC moved by the target actuator according to the target trajectory after the target velocity change will also be prevented from interfering with an obstacle or the like.

[0102] A specific example of the target speed change is shown below.

[0103] When the control target CT is moved by only a single target actuator, the controller 70 can change the target trajectory without changing the target path PA by changing only the operating speed of the single target actuator.

[0104] When the control target CT is moved by multiple target actuators, for example, when the control target CT is moved by the pair of travel motors 31, or when the control target CT moves in conjunction with the movement of two or more elements among the upper rotating body 13, the boom 15a, the arm 15b, and the end attachment 15c, the controller 70 performs the following process to change the target speed. That is, the controller 70 calculates, for each of the multiple target actuators, a required speed change amount, which is the amount of change in the target speed required to bring the required capacity Ar into the actuator capacity range Ra. The controller 70 changes the target speeds V of all of the multiple target actuators 30 according to the largest required speed change amount among the required speed change amounts of the multiple target actuators 30. More preferably, the controller 70 changes the target speeds while maintaining the ratio between the speeds of the multiple target actuators. This target speed change allows the target speed V to be appropriately revised without changing the target path PA.

[0105] More specifically, the controller 70 calculates, for example, the following required change ratio for each of the plurality of target actuators: The required change ratio is the ratio (=Vrvt / Vo) of a pre-revised target speed Vo, which is the target speed V before the target speed change, to a provisional revised target speed Vrvt calculated based on the required speed revision amount.

[0106] In a target speed change that reduces the target speed V, the controller 70 determines a minimum required change ratio, which is the smallest value among the required change ratios (=Vrvt / Vo) of the multiple target actuators, and changes (in this example, reduces) the target speeds V of all of the multiple target actuators based on this minimum required change ratio. Specifically, the controller 70 sets the product of the pre-revised target speed Vo and the minimum required change ratio for each of the multiple target actuators as the revised target speed Vrv for each target actuator.

[0107] In a target speed change that increases the target speed V, the controller 70 determines a maximum required change ratio, which is the largest value among the required change ratios (=Vrvt / Vo) of the multiple target actuators, and changes (here, increases) the target speeds V of the multiple target actuators based on this maximum required change ratio. Specifically, the controller 70 sets the product of the pre-revision target speed V1 of each of the multiple target actuators and the maximum required revision ratio as the revised target speed Vrv of each target actuator.

[0108] It is preferable that the controller 70, for example the automatic control controller 71, outputs information about the change in the target speed to the output unit 80. Specifically, it is preferable that the output unit 80 notifies an operator of the information about the change in the target speed.

[0109] When the target speed change has not been performed, the output unit 80 may output information indicating that the target speed has not been changed. The output unit 80 may output information regarding whether the target speed has been changed.

[0110] The output unit 80 preferably outputs a message that the target speed V has been changed as a result of the target speed change to notify an operator. This is to prevent the operator from recognizing that a malfunction of the target actuator has occurred because the target actuator and the control target CT move at a speed different from the speed before the target speed change due to the target speed change. By notifying the operator of the target speed change, the output unit 80 can prevent the operator from erroneously recognizing that a malfunction of the target actuator has occurred because the movement (behavior) of the target actuator and the control target CT is different from the movement set in the work plan before the target speed change.

[0111] The output unit 80 may output a reason for the target speed change. Specifically, the output unit 80 may output whether the target speed change being performed is a target speed change based on the device capability or a target speed change corresponding to output limit control.

[0112] The output unit 80 may output the details of the change of the target speed V from the pre-revised target speed Vo to the revised target speed Vrv. Specifically, the output unit 80 may output whether the change of the target speed is an increase or a decrease of the target speed V.

[0113] The output unit 80 may output the amount of change in the target speed V. For example, the output unit 80 may output the difference between the target speed Vo before the target speed change and the revised target speed Vrv, or may output the ratio between the two. The output unit 80 may output information about the time required for the control object CT to move from a position before the movement, for example, a current position, to a position after the movement, i.e., the required movement time. For example, the output unit 80 may output the difference between the required movement time before the target speed change and the required movement time after the target speed change, or may output the ratio between the two.

[0114] The timing at which the output unit 80 outputs information about the change in target speed can be set in various ways. For example, a change in target speed based on equipment capability can be made before the work machine 10 is moved by automatic control. If the target speed V is changed before the work machine 10 is moved, the output unit 80 may output information about the change in target speed before the work machine 10 is moved, or may output information while the work machine 10 is in operation. Furthermore, if the target speed V is changed while the work machine 10 is in operation, the output unit 80 outputs information about the change in target speed while the work machine 10 is in operation.

[0115] The output unit 80 may output a signal to prompt the operator to select whether or not to change the target speed V. For example, if automatic execution of a change to increase the target speed V is not desirable, it is preferable to execute the target speed change after confirming the operator's intention regarding whether or not to change the target speed V. For the confirmation, the output unit 80 preferably outputs a signal to prompt the operator to select whether or not to increase the target speed V, for example, by displaying a confirmation button to be operated by the operator. The controller 70 changes the target speed only when a selection to allow the target speed increase is input, for example, via the input unit 60, thereby preventing the target speed V from increasing against the operator's will. Conversely, the output unit 80 may output a signal to prompt the operator to select whether or not to decrease the target speed V.

[0116] The controller 70 may be configured to automatically determine whether to increase the target velocity V. For example, if the target velocity V before the change is excessively low and it is impossible to realize the movement of the control object CT along the target trajectory, the controller 70 may be configured to automatically determine whether to change the target velocity to increase the target velocity V.

[0117] Next, a specific example of the processing performed by the controller 70 will be described with reference to the flowchart shown in FIG.

[0118] In step S11, the work plan setting unit 71b of the controller 70 sets the work plan including the target trajectory. At this time, the work machine 10 shown in Fig. 1 is in an idling state, and in this idling state, the drive source (the engine 39 in this embodiment) is in a state where it can be driven, but the multiple actuators are stationary. If the drive source is a power source, the power source is turned on.

[0119] In step S12, the work plan change unit 71c of the controller 70 determines whether or not the work plan needs to be changed. The change in the work plan is specifically a change in the target speed based on the equipment capacity, and does not correspond to a change in the target speed corresponding to output limit control.

[0120] If it is determined that the work plan needs to be changed (YES in step S12), the work plan change unit 71c of the controller 70 changes the target speed based on the equipment capacity (step S13), and the automatic control controller 71 of the controller 70 finalizes the work plan including the target trajectory and notifies the output unit 80 of information on the finalized work plan (step S14). Specifically, the output unit 80 notifies the worker of the information by outputting information on the finalized work plan. If it is determined that the work plan does not need to be changed (NO in step S12), the controller 70 finalizes the current work plan and notifies the output unit 80 of information on the work plan.

[0121] In step S21, the automatic control controller 71 of the controller 70 determines whether or not to perform automatic control based on the state of the automatic control switch 63 shown in Fig. 2. Specifically, the automatic control controller 71 suspends the start of automatic control of the work machine 10 until the automatic control switch 63 is switched on (NO in step S21), and starts automatic control of the work machine 10 at the point in time when the automatic control switch 63 is switched on (YES in step S21). During the period from when the work machine 10 is operated by the automatic control until the automatic control switch 63 is switched off (NO in step S25), the controller 70 repeats the processing of the following steps S22 to S25 at every predetermined control cycle.

[0122] In step S22, the work plan change unit 71c of the controller 70 changes the target speed corresponding to output limit control. The work plan change unit 71c calculates the operating speed of the target actuator corresponding to the revised target speed Vrv. The target speed change is performed immediately (in real time) in accordance with the status of the working machine 10 during operation (e.g., pump pressure, etc.).

[0123] In step S23, the operation plan change unit 71c of the controller 70 calculates time information of the revised target trajectory based on the revised target speed Vrv. The time information may be, for example, the time between the two points or the target arrival time.

[0124] In step S24, the controller 70 calculates time information (for example, the target arrival time shown in FIG. 4) for each coordinate (for example, the X coordinate, the Y coordinate, and the Z coordinate). For example, the controller 70 replaces the time information (for example, the target arrival time) for each coordinate (for example, the X coordinate, the Y coordinate, and the Z coordinate) of a plurality of target points P1 to PN on the target route PA with revised time information (for example, the revised target arrival time).

[0125] The controller 70 repeats the processing of steps S22 to S25 until the automatic control switch 63 is switched off (NO in step S25), and ends the automatic control (step S31) when the automatic control switch 63 is switched on (YES in step S25). As a result, the working machine 10 stops operation under the automatic control and enters an idling state, for example. After the automatic control has ended, the controller 70 may resume the processing shown in Figure 6, or may completely end the processing.

[0126] According to the control system described above, when the required capacity Ar is outside the actuator capacity range Ra, the controller 70 changes the target speed V to the revised target speed Vrv without changing the target path PA so that the revised required capacity Arv falls within the actuator capacity range Ra. As a result, even when the target trajectory is set such that the required capacity Ar is outside the actuator capacity range Ra, the controller 70 can move the control object CT along the target path PA by moving it within the actuator capacity range Ra without changing the target path PA. This makes it possible to suppress deviation between the target path PA set before the target speed change and the actual movement of the control object CT while maintaining the target path PA. Therefore, if the target path PA before the target speed change is appropriately set, the control object CT can be moved along an appropriate path within the actuator capacity range Ra. For example, if the target path PA is set before the target speed is changed so as to prevent the control object TC from interfering with an obstacle, the target actuator can move the control object CT according to the target trajectory even after the target speed is changed, thereby preventing the control object CT from interfering with the obstacle.

[0127] 5 , when the required capacity Ar is greater than the actuator capacity range Ra, the controller 70 reduces the target speed V so that the revised required capacity Arv falls within the actuator capacity range Ra. As a result, even when the target trajectory is set such that the required capacity Ar is greater than the actuator capacity range Ra, for example, when a target trajectory requiring a capacity exceeding the maximum capacity of the target actuator is set, the controller 70 can cause the control target CT to follow the target path PA within the actuator capacity range Ra without changing the target path PA.

[0128] Conversely, if the required capacity Ar is smaller than the actuator capacity range Ra, the controller 70 increases the target speed V so that the revised required capacity Arv falls within the actuator capacity range Ra, as shown in Example 2 of FIG. 5 . As a result, even if the target trajectory is set such that the required capacity Ar is smaller than the actuator capacity range Ra, for example, even if a target trajectory is set that does not fully utilize the capacity of the target actuator, the controller 70 can cause the control target CT to follow the target path PA while appropriately utilizing the capacity of the target actuator without changing the target path PA. Furthermore, even if a target trajectory is set that requires a capacity less than the minimum output of the target actuator, the controller 70 can cause the control target CT to follow the target path PA while normally moving the target actuator 30 within the actuator capacity range Ra without changing the target path PA.

[0129] The controller 70 can appropriately calculate the maximum output acceleration taking the inertia into consideration by calculating the maximum output acceleration based on inertia information, which is information about the inertia of the target movable member including the controlled object, and information about the maximum output of the target actuator. By setting the appropriately calculated maximum output acceleration as the maximum value of the actuator capability range Ra, the actuator capability range Ra can be set to an appropriate range. By changing the target speed V so that the revised required capacity Ar falls within the actuator capability range Ra determined in this manner (without changing the target path PA), the controller 70 can calculate an appropriate revised target speed Vrv, i.e., prevent the revised target speed Vrv from being too high or too low.

[0130] The control system is provided with a notification unit, which in the embodiment is the output unit 80, that notifies the operator of the change in target speed, thereby enabling the operator to understand that the change in target speed has been made, and thereby preventing the operator from mistakenly recognizing the change in movement of the target actuator resulting from the change in target speed as a malfunction of the target actuator.

[0131] The controller 70 changes the target speed based on the output of the target actuator that is changed by the output limiting control, thereby being able to change the target speed V to an appropriate revised target speed Vrv regardless of fluctuations in the output of the target actuator due to the output limiting control.

[0132] The above-described embodiment may be modified in various ways. For example, modifications of the above-described embodiment may be combined in various ways. For example, the number of components (including modifications) of the above-described embodiment may be changed, or some of the components may not be provided. For example, the connections of the components shown in FIG. 2 may be changed. For example, the arrangement of the components may be changed. For example, the inclusion relationships of the components may be changed in various ways. For example, a component described as a lower-level component included in a higher-level component may not be included in the higher-level component, but may be included in another component. For example, what is described as multiple different components or parts may be combined into a single component or part. For example, what is described as a single component or part may be provided as multiple different components or parts. For example, the order of the steps in the flowchart shown in FIG. 6 may be changed, or some steps may not be performed. For example, values ​​such as thresholds and setting values ​​may be preset in the controller 70 or may be directly set by an operator through manual operation (operation of the input unit 60). Values ​​such as thresholds and setting values ​​may be calculated by the controller 70 based on information manually set by the operator, or may be calculated by the controller 70 based on information detected by the detection unit 40. For example, values ​​such as thresholds and set values ​​may not be changed, may be changed manually, or may be automatically changed by the controller 70 in response to certain conditions. For example, the controller 70 may perform substantially the same processing (calculation, determination, etc.) as the processing (calculation, determination, etc.) of the above-described embodiment (including modified examples). Various processing may be combined in various ways. For example, each component may have only a part of each feature (function, arrangement, shape, operation, etc.).

[0133] As described above, there is provided a control system for controlling a controlled object included in a work machine to move along a target path, which can suppress deviation between the target path and the actual movement of the controlled object. The control system includes an actuator that moves the controlled object and a controller. The controller is configured to: control the actuator to move the controlled object according to a target trajectory including information on the target path and target speed of the controlled object; calculate a required capacity, which is the capacity required of the actuator to move the controlled object according to the target trajectory; and, if the required capacity falls outside an actuator capacity range defined for the actuator, change the target speed to a revised target speed without changing the target path. The revised target speed is a speed at which a revised required capacity, which is the capacity required of the actuator to move the controlled object at the revised target speed, falls within the actuator capacity range.

[0134] According to the control system, even if a target trajectory is set such that the required capacity of the actuator falls outside the actuator capacity range, the deviation between the target path and the actual movement of the controlled object can be suppressed without changing the target path in the target trajectory.

[0135] Specifically, the controller is preferably configured to, when the required capacity is greater than an upper limit of the actuator capacity range, reduce the target speed so that the revised required capacity falls within the actuator capacity range.

[0136] Conversely, when the required capacity is smaller than the lower limit of the actuator capacity range, the controller is preferably configured to increase the target speed so that the revised required capacity falls within the actuator capacity range.

[0137] The required capacity may be a required acceleration that is an acceleration of the controlled object that is required to move the controlled object according to the target trajectory, and the upper limit of the actuator capacity range may be a maximum output acceleration that is an acceleration of the controlled object moved by a maximum output of the actuator. In this case, it is preferable that the controller is configured to calculate the maximum output acceleration based on inertia information related to the inertia of a movable member including the controlled object and information related to the maximum output of the actuator.

[0138] It is preferable that the control system further includes a notification unit that notifies an operator that the target speed has been changed to the revised target speed.

[0139] The controller may be configured to perform output limiting control to limit the output of the actuator. In this case, the controller is preferably configured to change the target speed based on the output of the actuator limited by the output limiting control.

Claims

1. A control system for controlling the movement of a controlled object included in a work machine, comprising: an actuator that moves the controlled object; and a controller, wherein the controller is configured to: control the actuator to move the controlled object according to a target trajectory including information on a target path and a target speed of the controlled object; calculate a required capacity, which is the capacity required of the actuator to move the controlled object according to the target trajectory; and if the required capacity falls outside an actuator capacity range defined for the actuator, change the target speed to a revised target speed without changing the target path, wherein the revised target speed is a speed at which revised required capacity, which is the capacity required of the actuator to move the controlled object at the revised target speed, falls within the actuator capacity range.

2. A control system according to claim 1, wherein the controller is configured to, when the requested capacity is greater than an upper limit of the actuator capacity range, reduce the target speed so that the revised requested capacity falls within the actuator capacity range.

3. A control system according to claim 1, wherein the controller is configured to, when the requested capacity is smaller than a lower limit of the actuator capacity range, increase the target speed so that the revised requested capacity falls within the actuator capacity range.

4. A control system as described in claim 1, wherein the required capacity is a required acceleration, which is the acceleration of the controlled object required to move the controlled object according to the target trajectory, the upper limit of the actuator capacity range is a maximum output acceleration, which is the acceleration of the controlled object moved by the maximum output of the actuator, and the controller is configured to calculate the maximum output acceleration based on inertia information regarding the inertia of a movable member including the controlled object and information regarding the maximum output of the actuator.

5. A control system according to claim 1, further comprising a notification unit for notifying an operator that the target speed has been changed to the revised target speed.

6. A control system according to claim 1, wherein the controller is configured to be capable of performing output limiting control for limiting the output of the actuator, and is configured to change the target speed based on the output of the actuator limited by the output limiting control.

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