control device

Abstract

The attachment is precisely controlled so that it moves along the target shape. [Solution] The controller 70 corrects the target shape T to the position of the controlled part 15s at the start of the tracking control t2 based on the deviation Et2 at the start of the tracking control. Alternatively, the controller 70 corrects the target shape T to a position between the controlled part 15s and the target shape T at the start of the tracking control t2 based on the deviation Et2 at the start of the tracking control. The controller 70 corrects the target shape T so that the offset amount To approaches 0 as the operation of the attachment 15 in tracking control progresses. The offset amount To is the difference between the target shape T before correction and the corrected target shape T.

Description

Technical Field

[0006] , ,

[0001] The present invention relates to a control device for controlling a working machine.

Background Art

[0002] For example, Patent Document 1 describes a technique for controlling a working machine based on the distance between an attachment (a working tool in the same document) and a target shape (a target construction terrain in the same document) (see, for example, Claim 1 of the same document). In this technique, the attachment is controlled so that the attachment moves along the target shape (see, for example, FIGS. and of the same document).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, when the attachment approaches the target shape and when the attachment reaches the target shape, it may be necessary to abruptly change the movement of the attachment. However, it is difficult to accurately perform control to abruptly change the movement of the attachment. As a result, it is difficult to accurately control the attachment so that the attachment moves along the target shape. ​​​​​​​​​The control device includes a controller that performs follow-up control. The follow-up control is a control that automatically moves the attachment of the work machine so that a specific part of the attachment to be followed moves along a target shape. The controller acquires the deviation at the start of the follow-up control. The deviation at the start of the follow-up control is the deviation of the part to be followed with respect to the target shape at the start of the follow-up control. Based on the deviation at the start of the follow-up control, the controller corrects the target shape to the position of the part to be followed at the start of the follow-up control. Alternatively, based on the deviation at the start of the follow-up control, the controller corrects the target shape to a position between the part to be followed at the start of the follow-up control and the target shape. As the work of the attachment in the follow-up control progresses, the controller corrects the target shape so that the offset amount approaches 0. The offset amount is the difference between the target shape after correction and the target shape before correction. [Effects of the Invention]

[0007] The above control device allows for precise control of the attachment so that it moves along the target shape. [Brief explanation of the drawing]

[0008] [Figure 1] This is a side view of the work machine 10 of the control device 1. [Figure 2] Figure 1 is a block diagram of the control device 1. [Figure 3] Figure 1 shows a side view of the corrected target shape T2, etc., when the offset amount To approaches 0 as the movement distance of the controlled part 15s increases. [Figure 4] This is a side view of the corrected target shape T2, etc., when the offset amount To approaches 0 as the elapsed time of movement of the controlled part 15s shown in Figure 1 increases. [Figure 5] Figure 1 is a side view showing the movement of the attachment 15 as the controlled part 15s moves along the corrected target shape T2. [Figure 6] Figure 1 is a graph showing the time-dependent changes in the height of the controlled part 15s and the operation commands for the boom 15a. [Figure 7] Figure 2 is a flowchart of Example 1 of the processing of the controller 70. [Figure 8] Figure 2 shows a flowchart of example 2 of the processing of the controller 70. [Modes for carrying out the invention]

[0009] The control device 1 will be described with reference to Figures 1 to 8.

[0010] The control device 1 is a device that controls the movement of the work machine 10 shown in Figure 1. The control device 1 comprises the work machine 10, the detection unit 40 shown in Figure 2, the input unit 60, the controller 70, and the output unit 80.

[0011] As shown in Figure 1, the work machine 10 is a machine that performs work. The work machine 10 may be a construction machine that performs construction work, or a material handling machine that performs material handling work. The work machine 10 may be, for example, a shovel or a crane. The work machine 10 may be a bulldozer or a wheel loader. Below, we will mainly describe the case where the work machine 10 is a shovel. The work machine 10 is configured to be operable by automatic control. The automatic control may be fully automatic or semi-automatic (described later). The work machine 10 may also operate in response to the operation of a worker (operator) without the use of automatic control. For example, the work machine 10 may be operated (onboard operation) by a worker in the driver's cab 13c (described later), or it may be remotely controlled from outside the work machine 10. The work machine 10 comprises a machine body 10a, an attachment 15, a drive control unit 17 (see Figure 2), and an actuator 30.

[0012] The machine body 10a is the main body of the work machine 10. The machine body 10a comprises a lower body 11 and an upper rotating body 13.

[0013] The lower body 11 supports the upper revolving body 13 in a rotatable manner. The lower body 11 may be a lower traveling body capable of traveling on a traveling surface (such as the ground). When the lower body 11 is capable of traveling, the lower body 11 may be provided with crawlers or may be provided with wheels.

[0014] The upper revolving body 13 is mounted on the lower body 11 in a rotatable manner. A boom 15a or the like is attached to the upper revolving body 13. The upper revolving body 13 includes an operator's cab 13c. The operator's cab 13c is a part where an operator can operate (board and operate) the work machine 10.

[0015] (Direction) The direction in which the rotation axis of the upper revolving body 13 rotates with respect to the lower body 11 is defined as the vertical direction Z. In the vertical direction Z, the side (direction) from the lower body 11 toward the upper revolving body 13 is defined as the upper side Z1, and the side opposite to the upper side Z1 is defined as the lower side Z2. The direction in which the rotation axis of the boom 15a extends with respect to the upper revolving body 13 is defined as the "lateral direction". The direction orthogonal to each of the vertical direction Z and the lateral direction is defined as the front-rear direction X. In the front-rear direction X, the side where the attachment 15 protrudes with respect to the upper revolving body 13 is defined as the rear side X1, and the side opposite to the rear side X1 is defined as the front side X2. The vertical direction Z may coincide with the vertical direction, may not coincide with the vertical direction, and each of the front-rear direction X and the lateral direction does not necessarily coincide with the horizontal direction.

[0016] The attachment 15 is a part for performing work. The attachment 15 is attached to the machine body 10a. For example, the attachment 15 includes a boom 15a, an arm 15b, a tip attachment 15c, and a control target part 15s (a follow-up control target part, a stop control target part).

[0017] The boom 15a is attached to the upper revolving body 13 so as to be rotatable (rotatable in the front-rear direction X and the vertical direction Z). The arm 15b is attached to the boom 15a so as to be rotatable (rotatable in the front-rear direction X and the vertical direction Z).

[0018] The tip attachment 15c is provided at the tip of the attachment 15. The tip attachment 15c is rotatably attached to the arm 15b (rotatable in the front-rear direction X and the up-down direction Z). The tip attachment 15c may be a bucket capable of performing operations such as scooping up the work object G and excavation. The tip attachment 15c may be provided with a device for clamping the work object G (such as a grapple, nibbler, rotary fork, etc.), may be provided with a device for crushing the work object G (such as a breaker, etc.), or may be provided with a magnet for adsorbing a metallic work object G. The work object G (construction object) is an object to be worked on by the working machine 10. The work object G may be in the form of soil, granular, chip-like, powdery, etc. The work object G may be earth and sand, rock, a magnetic body (such as metal), resin, waste, wood (such as a log), or a structure (such as a block).

[0019] The control target part 15s (tracking control target part, stop control target part) is a specific part of the attachment 15. For example, the control target part 15s is a specific part of the tip attachment 15c. For example, the control target part 15s may be the tip of the tip attachment 15c. The tip of the tip attachment 15c is the end of the tip attachment 15c on the opposite side to the attachment part (base end part) to the arm 15b. The tip of the tip attachment 15c is, for example, the tip of the bucket. Incidentally, the control target part 15s may be a specific part (such as the tip) of the arm 15b, or may be a specific part of the boom 15a.

[0020] This control target part 15s is a part to be the target of the tracking control described later (tracking control target part), and is a part that is controlled to move along the target shape T. The controller 70 described later controls the attachment 15 so that the control target part 15s moves along the target shape T in the tracking control.

[0021] This controlled part 15s is the part that is subject to the stop control described later (stop control target part), and is the part that is controlled to stop at the target stop position P1 (see Figure 3). The controller 70, described later, controls the attachment 15 in the stop control so that the controlled part 15s stops at the target stop position P1. Note that the follow control target part and the stop control target part may be the same part or different parts.

[0022] The drive control unit 17 (see Figure 2) controls the actuator 30. The drive control unit 17 may include a hydraulic circuit to control a hydraulic actuator that operates by hydraulic pressure. The drive control unit 17 may also include an electrical circuit to control an electric actuator that operates by electric power. The drive control unit 17 controls the travel motor 31, slewing motor 33, boom cylinder 35a, arm cylinder 35b, and tip attachment cylinder 35c, which will be described later.

[0023] The actuator 30 is a device that moves the work machine 10. The actuator 30 may be a hydraulic actuator that is driven by hydraulics, or an electric actuator that is driven by electricity. The actuator 30 may be a motor that rotates, or a cylinder that extends and retracts (extendable cylinder). The actuator 30 comprises a travel motor 31, a slewing motor 33, a boom cylinder 35a, an arm cylinder 35b, and a tip attachment cylinder 35c.

[0024] The travel motor 31 moves the lower body 11. The travel motor 31 may be a hydraulic motor or an electric motor (the same applies to the slewing motor 33). The slewing motor 33 slewing the upper slewing body 13 relative to the lower body 11. The boom cylinder 35a rotates the boom 15a relative to the upper slewing body 13. The boom cylinder 35a is, for example, a hydraulic cylinder (the same applies to the arm cylinder 35b and the tip attachment cylinder 35c). The arm cylinder 35b rotates the arm 15b relative to the boom 15a. The tip attachment cylinder 35c rotates the tip attachment 15c relative to the arm 15b. If the tip attachment 15c itself is drivable, for example, as a device for gripping objects, an actuator 30 for driving the tip attachment 15c may be provided. In the following, the work machine 10 and its components will be described with reference to Figure 1 (however, the drive control unit 17 will be described with reference to Figure 2).

[0025] The detection unit 40 (see Figure 2) detects various states. Part or all of the detection unit 40 shown in Figure 2 may be mounted on the work machine 10 or located outside the work machine 10. The same applies to the input unit 60, controller 70, and output unit 80, which will be described later, in that they may be mounted on the work machine 10 or located outside the work machine 10. The detection unit 40 may detect the state of the work machine 10 or the state of the environment outside the work machine 10 (surrounding conditions). The detection unit 40 includes a posture detection unit 50.

[0026] The posture detection unit 50 detects the posture of the work machine 10. The posture detection unit 50 may also detect the position and orientation of the work machine 10 relative to the work site. The posture detection unit 50 may also detect the position and orientation of the reference position of the work machine 10 relative to the work site. The reference position of the work machine 10 may be, for example, a specific position on the upper slewing body 13 or the lower body 11. The reference position of the work machine 10 may be the attachment point (boom foot) of the boom 15a to the upper slewing body 13, or a specific position on the pivot axis of the upper slewing body 13 relative to the lower body 11. The posture detection unit 50 may also detect the inclination of the work machine 10 with respect to the horizontal plane. The posture detection unit 50 may also detect information (angle, angular velocity, angular acceleration, etc.) about the rotation of the upper slewing body 13 relative to the lower body 11. The posture detection unit 50 may also detect information (angle, angular velocity, angular acceleration, etc.) about the rotation of the boom 15a relative to the upper slewing body 13. The attitude detection unit 50 may detect information about the rotation of the arm 15b relative to the boom 15a. The attitude detection unit 50 may also detect information about the rotation of the bucket relative to the arm 15b.

[0027] The attitude detection unit 50 may be equipped with one or more types of detection devices. The attitude detection unit 50 may be equipped with a detection device (e.g., a rotary encoder) that detects information about the angle of one element of the work machine 10 relative to another element. The attitude detection unit 50 may be equipped with a stroke sensor that detects the stroke of the cylinder (e.g., a boom cylinder 35a) that moves the attachment 15. The attitude detection unit 50 may be equipped with a tilt sensor that detects the angle (tilt) with respect to the horizontal direction. The attitude detection unit 50 may be equipped with a sensor (e.g., a gyro sensor) that detects the angular velocity relative to the work site, and may be equipped with a sensor that detects the acceleration relative to the work site. The attitude detection unit 50 may be equipped with an inertial measuring device or the like.

[0028] The posture detection unit 50 may include a position detection unit that detects the position of a specific part (one or more parts) of the work machine 10 at the work site. In this case, the posture detection unit 50 may detect the posture of the "specific part of the work machine 10" based on the position information detected by the position detection unit. The posture detection unit 50 may include a direction detection unit that detects the direction of the specific part of the work machine 10. The posture detection unit 50 may include an imaging device that detects images. The posture detection unit 50 may detect the posture of the work machine 10 based on image recognition of a two-dimensional image. The posture detection unit 50 may detect the posture of the work machine 10 based on a three-dimensional image (distance image). The posture detection unit 50 may detect the posture of the work machine 10 based on a three-dimensional image (distance image) and a two-dimensional image.

[0029] The input unit 60 is for inputting information (input device). The input unit 60 is operated by an operator and outputs a signal corresponding to the operation. The input unit 60 outputs information to the controller 70. The input unit 60 may be equipped with a touch panel, a mouse, a keyboard, or switches. The input unit 60 may be installed on a tablet, a smartphone, or a personal computer. The input unit 60 may be installed on the work machine 10, for example, in the operator's cab 13c. The input unit 60 may be installed on a remote control device for remotely operating the work machine 10. The input unit 60 may be equipped with switches installed on the operation unit 61 (for example, an operation lever), or with switches installed on a display unit (for example, a cluster gauge) that displays information about the work machine 10. The input unit 60 is equipped with the operation unit 61.

[0030] The control unit 61 is operated by a worker (operator) who operates the work machine 10. The control unit 61 receives input for operations to move the work machine 10. The control unit 61 may be located in the driver's cab 13c or it may be located in a remote control device for remotely controlling the work machine 10. The control unit 61 may be equipped with a lever (operating lever) or a pedal (operating pedal). The control unit 61 outputs a command corresponding to the operation input to the control unit 61. The control unit 61 may output a command corresponding to the amount of operation input to the control unit 61. The control unit 61 may receive input for operations to move the lower body 11 (traveling operation). The control unit 61 may receive input for operations to rotate the upper slewing body 13 relative to the lower body 11 (slewing operation). The control unit 61 may receive input for operations to move the attachment 15 (attachment operation). The control unit 61 may receive input for an operation to rotate the boom 15a relative to the upper slewing body 13 (boom operation). The control unit 61 may receive input for an operation to rotate the arm 15b relative to the boom 15a (arm operation). The control unit 61 may receive input for an operation to rotate the tip attachment 15c relative to the arm 15b (tip attachment operation).

[0031] The controller 70 is a computer that performs signal input / output, calculations (processing), and information storage. The functions of the controller 70 are realized by the execution of a program stored in the storage unit 70b of the controller 70 by the calculation unit 70a. The controller 70 may be connected to other devices by wireless communication or by wired communication. The components of the controller 70 may be connected to each other by wireless communication or by wired communication. For example, communication may be performed by means of communication such as a mobile phone line, optical line, wireless LAN (Local Area Network), or wired LAN. For example, information is input to the controller 70 from the detection unit 40 and the input unit 60. For example, the controller 70 outputs a command (signal) to the drive control unit 17 to move the work machine 10. For example, the controller 70 outputs information to the output unit 80. The controller 70 may be mounted on the work machine 10 or located outside the work machine 10. The controller 70 may be distributed and located in multiple parts (it may constitute a distributed system). The controller 70 comprises a calculation unit 70a and a storage unit 70b. Focusing on the functions of the controller 70, it comprises a work plan setting unit 71 and an automatic control unit 73. The controller 70 will be described below with reference to Figure 2.

[0032] The arithmetic unit 70a performs calculations (processing) of information. The storage unit 70b stores the information.

[0033] The work plan setting unit 71 sets the work plan for the work machine 10. The work plan is information about the objective of the work of the work machine 10. For example, the work plan includes information about the target shape T (see Figure 3) for the follow control described later. The work plan may also include information about the follow control start position P2 (see Figure 3) described later. The work plan may also include information about the target stop position P1 (see Figure 3) for the stop control described later.

[0034] The automatic control unit 73 automatically controls the movement (including stopping) of the work machine 10. The automatic control unit 73 may control the movement of the work machine 10 in fully automatic operation or in semi-automatic operation. The automatic control unit 73 outputs commands to the drive control unit 17 so that the work machine 10 moves automatically or semi-automatically according to the work plan. The automatic control unit 73 controls the movement of the work machine 10 based on the posture detected by the posture detection unit 50. The automatic control unit 73 performs follow-up control, which will be described later. The automatic control unit 73 may also perform stop control (including deceleration control), which will be described later.

[0035] The output unit 80 is an information output device. The output unit 80 outputs information based on the signal output from the controller 70. The output unit 80 may output light (such as a display), sound (such as voice), or vibration. The output unit 80 may be provided in a tablet, a smartphone, or a personal computer. The output unit 80 may be provided in the driver's cab 13c. The output unit 80 may be provided in a remote control device for remotely operating the work machine 10. The output unit 80 may be equipped with a display device (monitor).

[0036] (Operation of work machine 10) As described above, the work machine 10 shown in Figure 1 may be operated by an operator in the operator's cab 13c (onboard operation), remotely operated by an operator from outside the work machine 10 (remote control device), or operated automatically. The work machine 10 is a machine that utilizes information and communication technology (ICT; for example, ICT construction machinery). For example, the work machine 10 may be operated by machine control system (MC; semi-automatic operation). Specifically, a work plan (for example, target shape T) is set in the controller 70. Then, the operator operates only some elements of the attachment 15 (for example, only the arm 15b). At this time, the controller 70 automatically controls the elements not operated by the operator (for example, the boom 15a and the tip attachment 15c) so that the work machine 10 moves according to the work plan (specific examples will be described later). At this time, the controller 70 controls the movement of the work machine 10 based on the information detected by the attitude detection unit 50 (the same applies in the case of automatic operation). As a result, the work machine 10 moves according to the work plan.

[0037] Alternatively, for example, the work machine 10 may operate automatically. In this case, the controller 70 controls the movement of the work machine 10 so that it moves automatically according to the work plan.

[0038] (Follow-up control) The controller 70 performs tracking control. As shown in Figure 3, tracking control is a control that automatically moves the attachment 15 so that the controlled part 15s (more specifically, the part subject to tracking control) moves along the target shape T (approaches the target shape T).

[0039] The target shape T is information about the shape of the target movement path (target path) of the controlled part 15s. For example, the target shape T may be a surface (surface information). The target shape T, which is a surface, may also be a target construction surface. For example, the target construction surface is the target shape of the surface (e.g., the ground) of the work object G (e.g., soil) after the work is performed by the work machine 10 in follow control, when the work is an excavation operation to excavate the work object G (e.g., soil) (hereinafter also referred to as "when excavation work is performed in follow control"). The target shape T may include one or more planes (flat surfaces). This plane may be a horizontal surface, a vertical surface, or a surface inclined with respect to the horizontal direction (inclined surface). The target shape T may include one or more curved surfaces. The target shape T may also be a surface that combines a plane and a curved surface. The target shape T may also be a line (line information). The target shape T may include one or more straight lines, one or more curves, or a line that combines a straight line and a curve. The target shape T may also include information that includes the positions (coordinates) of multiple target points and information that includes the order of each target point.

[0040] The target shape T may be set by various methods (the same applies to the method of setting information other than the target shape T). For example, information such as the target shape T may be set based on manual operation (manual input) by the operator of the input unit 60 (see Figure 2), or it may be information (initial value, initial information) that has been set in advance in the controller 70. Information such as the target shape T may also be set automatically by the controller 70 based on some condition (for example, the detection result of the detection unit 40 (see Figure 2)). Information such as the target shape T may also be stored in an external storage device of the controller 70 and set in the controller 70 by being read by the controller 70.

[0041] (Specific example of follow-up control) Follow-up control may be performed in semi-automatic or automatic operation. A specific example of follow-up control being performed in semi-automatic operation is as follows. Here, we will explain an example in which follow-up control is performed in semi-automatic operation by arm operation. In this example, the operator performs arm operation on the control unit 61 (see Figure 2) to rotate the arm 15b relative to the boom 15a shown in Figure 1. Arm operation includes an arm push operation that moves the tip of the arm 15b towards the back X1, and an arm pull operation that moves the tip of the arm 15b towards the front X2. The arm 15b moves in the forward / backward direction X in response to the arm operation performed on the control unit 61 (manual operation). In semi-automatic follow-up control, when the operation involves moving the tip attachment 15c in the forward / backward direction X, the operator can intuitively operate the system by performing semi-automatic operation by moving the arm 15b in the forward / backward direction X (arm operation). Furthermore, the operation of the control unit 61 during semi-automatic operation does not necessarily have to be arm operation; for example, it could be boom operation or slewing operation.

[0042] When operation is performed in semi-automatic mode (for example, arm operation), the controller 70 automatically controls the movement of the boom 15a. More specifically, the controller 70 automatically controls the boom 15a so that it rotates in the vertical direction Z relative to the upper slewing body 13. More specifically, the controller 70 calculates the position of the controlled part 15s from the attitude information detected by the attitude detection unit 50 (see Figure 2). The controller 70 calculates the deviation E of the position of the controlled part 15s relative to the target shape T shown in Figure 3. Then, the controller 70 automatically controls the boom 15a shown in Figure 1 (for example, proportional control) so that the deviation E approaches 0. Through this control, the controlled part 15s moves along the target shape T. For example, when excavation work is performed with follow control, it is assumed that the tip of the bucket (cutting edge) is set as the controlled part 15s. In this case, the tip of the bucket moves along the target shape T with follow control and excavates the work object G. As a result, the position and shape of the surface of the work object G (e.g., the ground) will be the same as, or approximately the same as, the position and shape of the target shape T (target construction surface).

[0043] In the example above, the controller 70 automatically controlled the boom 15a, but the controller 70 may also automatically control the movement of the tip attachment 15c. Furthermore, when follow control is performed in automatic operation, the controller 70 also automatically controls the elements that move in response to the operation of the control unit 61 in semi-automatic operation (the arm 15b in the example above).

[0044] As shown in Figure 3, the deviation E is the difference (deviation) in the position of the controlled part 15s relative to the target shape T. The deviation E may be a distance deviation E or an angle deviation E (see Figure 5). The distance deviation E is the difference in distance of the controlled part 15s relative to the target shape T in a certain direction (for example, the tracking crossing direction W described later). For example, if the above "certain direction" is the vertical direction Z, the distance deviation E is the distance deviation E (height deviation) in the vertical direction Z (height direction). As shown in Figure 5, the angle deviation E is defined, for example, as follows: A reference center point O is set. The center point O may be, for example, a position on the target shape T, or a specific position on the machine body 10a (lower body 11 or upper rotating body 13) shown in Figure 1. As shown in Figure 5, the line segment connecting the center point O and the controlled part 15s is called line segment L1. The arc with center point O as the center and radius equal to the length of line segment L is called arc C. Let L2 be the line segment connecting the intersection point of arc C and target shape T to the center point O. In this case, let E be the angle between line segments L1 and L2. Figure 5 shows the angle deviation E when the target shape T extends in the front-to-back direction X, and a point on the target shape T is the center point O.

[0045] (Directions regarding automatic control) As shown in Figure 3, the directions of automatic control by the controller 70 include a tracking direction U and a tracking intersection direction W. The tracking direction U is the direction along the target shape T (the pre-correction target shape T1, which will be described in more detail later) (the direction in which the target shape T extends). In the tracking direction U, the direction of movement of the controlled part 15s in tracking control (the direction of travel, the direction in which the attachment 15 performs the work) is defined as the work travel side U2. The tracking intersection direction W is the direction that intersects (for example, orthogonal to) the tracking direction U. The tracking intersection direction W may also be, for example, the direction of the distance deviation E. In the tracking intersection direction W, the side (direction) from the controlled part 15s towards the pre-correction target shape T1 before the start of tracking control is defined as the approach side W2, and the side opposite to the approach side W2 is defined as the anti-approach side W1.

[0046] In the example shown in Figure 3, the direction along the pre-correction target shape T1 is the front-rear direction X, so the tracking direction U is the front-rear direction X. The tracking direction U may also be the up-down direction Z, the side-to-side direction, or a direction that intersects these directions. In the example shown in Figure 3, the pre-correction target shape T1 is linear, but if the pre-correction target shape T1 is curved, the tracking direction U will be the direction along the curved pre-correction target shape T1. In the example shown in Figure 3, the work progress side U2 is the near side X2. Which side of the tracking direction U becomes the work progress side U2 may be determined by the direction of operation of the operator's control unit 61 (see Figure 2), or it may be set in advance in the controller 70. In the example shown in Figure 3, the tracking intersection direction W (direction of deviation E) is the up-down direction Z (height direction). In the example shown in Figure 3, the approaching side W2 is the lower side Z2, and the anti-approaching side W1 is the upper side Z1. The following section will primarily describe the case where the tracking direction U is the forward / backward direction X, the work progress side U2 is the forward side X2, the tracking crossing direction W is the up / down direction Z, the approaching side W2 is the downward side Z2, and the anti-approaching side W1 is the upward side Z1.

[0047] (Timing of the start of follow-up control) The timing for starting the follow control (also called the start time t2 of follow control) can be set in various ways. Follow control may be started by manual operation, or it may be started automatically by the controller 70.

[0048] The controller 70 may start follow control when an operation to start follow control is performed on the input unit 60 (see Figure 2). Specifically, the "operation to start follow control" is, for example, an operation to turn on a switch that commands to start semi-automatic operation (MC switch, MC start switch, etc. (an example of the input unit 60)).

[0049] The controller 70 may automatically start tracking control when predetermined conditions are met. The "predetermined conditions" may be, for example, when a specific part of the attachment 15 (e.g., the controlled part 15s) reaches the tracking control start position P2. The tracking control start position P2 (e.g., MC start position, MC start height) is set in advance in the controller 70 (before tracking control starts). The tracking control start position P2 is set to a position different from the target shape T (specifically, the pre-correction target shape T1). The tracking control start position P2 is set to a position a predetermined distance away from the target shape T on the anti-approach side W1 (e.g., the upper side Z1). This "predetermined distance" is set in advance in the controller 70 (before tracking control starts). The tracking control start position P2 may be the same position as the target stop position P1 described later (details will be described later).

[0050] (Correction of target shape T) The controller 70 corrects the target shape T at the start of follow-up control t2. The outline of the correction of the target shape T is as follows: The controller 70 acquires the deviation Et2 at the start of follow-up control. Based on the deviation Et2 at the start of follow-up control, the controller 70 corrects the target shape T to the position of the controlled part 15s at the start of follow-up control t2. Alternatively, the controller 70 corrects the target shape T to a position between the controlled part 15s and the target shape T at the start of follow-up control t2, based on the deviation Et2 at the start of follow-up control. The controller 70 corrects the target shape T so that the offset amount To approaches 0 (zero) as the operation of the attachment 15 in follow-up control progresses. Here, the target shape T before correction is called the pre-correction target shape T1. The target shape T after correction is called the post-correction target shape T2. The details of the correction of the target shape T are as follows.

[0051] (Correction of target shape T at the start of tracking control) The controller 70 acquires the tracking control start deviation Et2. The tracking control start deviation Et2 is the deviation E of the position of the controlled part 15s at the start of tracking control t2 with respect to the target shape T (specifically, the pre-correction target shape T1).

[0052] The controller 70 corrects the target shape T at the start of tracking control t2. At this time, the controller 70 corrects the target shape T according to the deviation Et2 at the start of tracking control (setting the corrected target shape T2). Specifically, the controller 70 determines the offset amount To according to the deviation Et2 at the start of tracking control. The offset amount To is the difference between the corrected target shape T2 and the target shape T1 before correction. For example, if the deviation E is a distance deviation E, the offset amount To is also expressed as distance (distance in the direction of the deviation E (tracking crossing direction W)). For example, if the deviation E is an angle deviation E (see Figure 5), the offset amount To is also expressed as an angle. Note that if the deviation E is a distance deviation E, the offset amount To may be expressed as an angle, and if the deviation E is an angle deviation E, the offset amount To may be expressed as distance.

[0053] [Setting Example A1] For example, the controller 70 may correct the target shape T to the position of the controlled part 15s at the start of tracking control t2 (e.g., the MC start coordinate) (set the corrected target shape T2). More specifically, the controller 70 may set the position of the controlled part 15s at the start of tracking control t2 as the position of the controlled part 15s at the start of tracking control t2. In this case, the controller 70 sets the deviation Et2 at the start of tracking control as the offset amount To. The controller 70 sets the position (e.g., height) of the corrected target shape T2 in the tracking intersection direction W as the position (e.g., height) of the controlled part 15s at the start of tracking control t2 in the tracking intersection direction W.

[0054] [Setting Example A2] For example, the controller 70 may correct the target shape T (set the corrected target shape T2) to a position between the position of the controlled part 15s at the start of tracking control t2 and the target shape T (specifically, the pre-correction target shape T1). Specifically, the controller 70 may set the position of the corrected target shape T2 that the controlled part 15s targets at the start of tracking control t2 to a position between the position of the controlled part 15s at the start of tracking control t2 and the pre-correction target shape T1. In this case, the controller 70 sets the offset amount To to be smaller than the deviation Et2 at the start of tracking control and greater than 0. The controller 70 sets the position (e.g., height) of the corrected target shape T2 in the tracking intersection direction W to be closer to the controlled part 15s at the start of tracking control t2 W2 (e.g., lower Z2) and away from the pre-correction target shape T1 W1 (e.g., upper Z1).

[0055] (Corrected target shape T2 after the start of tracking control (time t3)) The controller 70 corrects the target shape T so that the offset amount To approaches 0 (gradually decreases) as the attachment 15's work progresses in follow-up control. The controller 70 sets the offset amount To to 0 when the progress of the attachment 15's work reaches a predetermined level (at time t4). At this time, the controller 70 makes the corrected target shape T2 match the pre-correction target shape T1. The "progress of work" of the attachment 15 in follow-up control may be the distance traveled or the time traveled.

[0056] [Setting Example B1] The details of the case where the "work progress" of attachment 15 in follow-up control is the distance moved by attachment 15 are as follows: The controller 70 corrects the target shape T so that the offset amount To approaches 0 according to the distance moved by the controlled part 15s (more specifically, the distance moved in the follow-up direction U) in follow-up control (from the start of follow-up control t2). The controller 70 decreases the offset amount To as the distance moved by the controlled part 15s (from the start of follow-up control t2) increases in follow-up control.

[0057] [Setting Example B2] The details of the case where the "progress of work" of attachment 15 in follow control is the movement time of attachment 15 are as follows. As shown in Figure 4, the controller 70 corrects the target shape T so that the offset amount To approaches 0 according to the elapsed time of movement of the controlled part 15s in follow control. The "elapsed time of movement of the controlled part 15s in follow control" is the total time (cumulative time) that the controlled part 15s has been moving since the start of follow control t2. The controller 70 reduces the offset amount To as the elapsed time of movement of the controlled part 15s in follow control increases. In this case, the slower the movement speed of the controlled part 15s (for example, a very slow operation), the smaller the distance that the controlled part 15s moves in the follow direction U from the start of follow control until the offset amount To becomes 0. When the movement speed of attachment 15 is slow, the offset amount To becomes 0 with only a small movement (immediately) of the controlled part 15s in the tracking direction U. The corrected target shape T2-2 shown in Figure 4 is the corrected target shape T2 when the movement speed of the controlled part 15s is fast, and the corrected target shape T2-1 is the corrected target shape T2 when the movement speed of the controlled part 15s is slow.

[0058] In this case, when excavation work is performed using follow-up operation, there is a process (finishing work) to finish the work object G (see Figure 1) to a shape that conforms to the target shape T with as much accuracy as possible. In finishing work, the accuracy of the position of the attachment 15 is important, so the movement speed of the attachment 15 is often slowed down. When finishing work is performed in semi-automatic operation, the attachment 15 is often operated at a very slow speed. If the above "progress of work" refers to the passage of time, then slowing down the movement speed of the attachment 15 in the finishing work reduces the distance the attachment 15 moves in the follow-up direction U from the start of follow-up control until the offset amount To becomes 0. Therefore, in finishing work, the work object G (see Figure 1) can be brought closer to a shape that conforms to the pre-correction target shape T1 (the original target shape T) (the work (construction) can be performed as intended).

[0059] [Setting Example C1] As shown in Figure 3, the controller 70 may set the shape of the corrected target shape T2 to be different from the shape of the pre-correction target shape T1. Specifically, the controller 70 sets the position of the corrected target shape T2 that the controlled part 15s targets at the start of the tracking control t2 (the starting position of the tracking control) according to the deviation Et2 at the start of the tracking control (as described above). After the start of the tracking control (time t3), the controller 70 may set the shape of the corrected target shape T2 such that the offset amount To approaches 0 as the corrected target shape T2 shifts from the starting position of the tracking control in the tracking direction U.

[0060] [Setting Example C2] The controller 70 may set the shape of the corrected target shape T2 to be the same as the shape of the pre-correction target shape T1 (not shown). Specifically, for example, if the pre-correction target shape T1 is a plane (flat surface), the controller 70 may set the corrected target shape T2 to a plane. More specifically, at the start of tracking control t2, the controller 70 may set the corrected target shape T2 to a position shifted by an offset amount To from the pre-correction target shape T1 without changing the shape of the pre-correction target shape T1. Alternatively, after the start of tracking control (time t3), the controller 70 may set the shape of the corrected target shape T2 to be the same as the shape of the pre-correction target shape T1, and gradually reduce the offset amount To as the work of the attachment 15 progresses.

[0061] [Setting Example D] The controller 70 may set the corrected target shape T2 on both sides of the tracking direction U (for example, the far side X1 and the near side X2) with respect to the position of the controlled part 15s at the start of tracking control t2. Specifically, for example, the controller 70 may set the corrected target shape T2 for each operation, such as the operation performed by pulling the arm and the operation performed by pushing the arm. If the direction of the work progress side U2 in tracking control is predetermined (for example, if it is set in the controller 70 in advance), the controller 70 may set the corrected target shape T2 only on the work progress side U2. Also, if the controller 70 corrects the target shape T so that the offset amount To approaches 0 according to the elapsed time of movement of the controlled part 15s in tracking control (in the case of [Setting Example B2] above), the corrected target shape T2 is set only on the work progress side U2.

[0062] (Path shape of the controlled part 15s along the corrected target shape T2) The path shape T2p is defined as the shape of the path (movement path) of the controlled part 15s when it moves along the corrected target shape T2. Here, the path shape T2p is assumed to be the shape of the (ideal) path of the controlled part 15s, assuming that the controlled part 15s moves precisely along the corrected target shape T2 (see [Example E1 of path shape T2p] described later). Note that if the corrected target shape T2 is set as in [Setting Example A1] and [Setting Example C1] above, the path shape T2p will be the shape of the corrected target shape T2 itself.

[0063] The path shape T2p may include one or more straight lines. These straight lines may be inclined with respect to the pre-correction target shape T1. The inclination (gradient) of these straight lines with respect to the pre-correction target shape T1 can be set in various ways. The path shape T2p may include one or more curves. These curves may be arc-shaped (e.g., circular arcs), S-shaped, etc. These curves may be curves that smoothly (without bending) continue (connect) to the pre-correction target shape T1. The path shape T2p may also be a shape that combines straight lines and curves. In the example shown in Figure 3, the path shape T2p is a straight line from the position of the controlled part 15s at the start of follow-up control t2 (more precisely, near this position) to a predetermined position, and beyond this "predetermined position" U2, it is a curve that smoothly continues to the pre-correction target shape T1.

[0064] (Control to track the corrected target shape T2) After correcting the target shape T, the controller 70 automatically moves the attachment 15 so that the controlled part 15s approaches the corrected target shape T2. More specifically, the controller 70 automatically controls the attachment 15 (for example, proportional control) so that the actual deviation E_real approaches 0. The actual deviation E_real is the difference in position of the controlled part 15s relative to the corrected target shape T2. Further details of the tracking control are as described in "(Specific Example of Tracking Control)" above.

[0065] (Comparison of cases where the target shape T is corrected versus cases where it is not corrected) The following are specific examples of the operation of the work machine 10 when the target shape T is corrected and when it is not corrected.

[0066] Before the start of follow control (time t1), the controlled part 15s is moved from a position W1 (e.g., upper Z1) on the opposite side of the follow control start position P2 to a position W2 (e.g., lower Z2) on the approaching side. Before the start of follow control (time t1), the work machine 10 may be operated by an operator (onboard operation, remote operation), may be moved by semi-automatic operation, or may be moved by automatic operation. In the example shown in Figure 6, from time t1 to the start of follow control t2, the boom operation command is "down". At this time, the boom 15a (see Figure 1) is lowered (moved to lower Z2), which lowers the controlled part 15s. When the controlled part 15s shown in Figure 3 moves to the approaching side W2 (for example, the lower side Z2) and reaches the follow control start position P2 (see Figure 3) (for example, the follow control start height P2z (see Figure 6)) (when follow control starts t2), the controller 70 starts follow control.

[0067] (Example of a problem when the target shape T is not corrected) A specific example of the operation of the work machine 10 when follow-up control is performed without correction of the target shape T is as follows. In this case, the controller 70 automatically controls the attachment 15 so that the controlled part 15s moves toward the target shape T (towards the approaching side W2) by follow-up control. In the example shown in Figure 6, even after the start of follow-up control t2, the controller 70 controls the boom operation command to be "down" from time t1, just as at the start of follow-up control t2 (see the comparative example shown in Figure 6), and controls the boom 15a to be lowered.

[0068] Then, the controlled part 15s reaches the target shape T (the position of the pre-correction target shape T1 in this embodiment). This time is denoted as time t4. At the moment the controlled part 15s reaches the target shape T (at time t4), the controller 70 abruptly changes the movement of the components of the attachment 15 (see Figure 1). For example, the controller 70 abruptly stops the components of the attachment 15. Depending on the conditions, the controller 70 may also move the components of the attachment 15 in opposite directions before and after time t4 (causing a sharp reversal (switching) operation). In the comparative example shown in Figure 6, the controller 70 controls the boom 15a to be lowered before time t4, and controls the boom 15a to be raised after time t4. Thus, in the comparative example shown in Figure 6, the controller 70 attempts to control a sharp reversal operation of the boom 15a at the moment of time t4.

[0069] However, it is difficult for the controller 70 to accurately control the abrupt changes in the movement of the components of the attachment 15 (e.g., boom 15a) (sudden stops, reversing movements). Examples of the reasons for this are as follows: There is a delay between the time the controller 70 outputs a command to move the actuator 30 shown in Figure 1 and the time the actuator 30 actually moves according to the command (there is an effect of responsiveness). Also, the load on the actuator 30 changes as the force that the attachment 15 (specifically the tip attachment 15c) receives from the workpiece G changes, so the command value required to move the actuator 30 changes (there is an effect of load fluctuations). In addition, it is difficult to move the attachment 15 abruptly due to the inertial force caused by the attachment 15's own weight. For these reasons, it is difficult for the controller 70 to accurately control the abrupt changes in the movement of the components of the attachment 15. Therefore, it is difficult to make the controlled part 15s accurately follow the target shape T at the moment it reaches the target shape T (at time t4). Specifically, it is difficult to accurately bring the deviation E (see Figure 3) close to zero. As a result, as shown in the comparative example in Figure 6, the controlled part 15s may move toward the approaching side W2 (for example, the lower side Z2) toward the target shape T, and after reaching the target shape T, it may move beyond the target shape T (for example, move toward the lower side Z2).

[0070] For example, when excavation work is performed using follow-up control, if the target shape T is exceeded, the attachment 15 shown in Figure 1 will excavate the work object G beyond the target shape T (excavating too much). In this case, additional work (additional construction) will be required to replenish the work object G in the over-excavated position and perform the excavation work again using follow-up control along the target shape T. Furthermore, even when work other than excavation is performed using follow-up control, it is undesirable for the controlled part 15s to exceed the target shape T. Therefore, it is important to make the controlled part 15s accurately follow the target shape T (move along the target shape T).

[0071] (When correcting the target shape T) Therefore, in this embodiment, as shown in Figure 3, the controller 70 corrects the target shape T to the position of the controlled part 15s at the start of tracking control t2 (setting the corrected target shape T2) (as in [Setting Example A1] above). Alternatively, the controller 70 corrects the target shape T to a position between the controlled part 15s and the target shape T (pre-correction target shape T1) at the start of tracking control t2 (setting the corrected target shape T2) (as in [Setting Example A2] above). Thus, the controlled part 15s is more likely to reach the corrected target shape T2 before reaching the pre-correction target shape T1 (original target shape T) (before time t5). Specifically, in the case of [Setting Example A1] above, the controlled part 15s reaches the corrected target shape T2 at the start of tracking control t2. Furthermore, in the case of the above [Setting Example A2], the controlled part 15s is likely to reach the corrected target shape T2 before it reaches the pre-correction target shape T1 (early, before time t5).

[0072] Therefore, the controller 70 is likely to perform control that changes the movement (stop, reverse) of the components of the attachment 15 (e.g., boom 15a) before the controlled part 15s reaches the pre-correction target shape T1. Therefore, when the controlled part 15s reaches the pre-correction target shape T1 (time t5), the need to abruptly change the movement of the components of the attachment 15 (sudden stop, sharp reverse) can be suppressed. As a result, as shown in Figure 6, from the moment the controlled part 15s reaches the pre-correction target shape T1 (time t5), it becomes possible to make the controlled part 15s accurately follow the pre-correction target shape T1 (move along the target shape T). For example, when excavation work is performed with follow control, the attachment 15 shown in Figure 1 is prevented from digging beyond the target shape T into the work object G (over-digging is suppressed).

[0073] In the example shown in Figure 6, when the controlled part 15s reaches the corrected target shape T2 (time t2 when follow-up control starts), the controller 70 starts follow-up control, sets the boom operation command to "raise", and controls the boom 15a to rise (see Figure 5). The controller 70 then continues to control the boom 15a to rise even after the start of follow-up control t2 (without stopping or reversing). In the example shown in Figure 6, the controller 70 also controls the boom 15a to rise when the controlled part 15s reaches the pre-correction target shape T1 (time t5) (without stopping or reversing).

[0074] (Information output) The controller 70 may output (for example, display) information regarding the corrected target shape T2 to the output unit 80 (see Figure 2 (the same applies to the output unit 80 below)).

[0075] (Display of path shape T2p) The controller 70 may also display the path shape T2p of the controlled part 15s along the corrected target shape T2 shown in Figure 3 on the output unit 80. In this case, the operator looking at the output unit 80 can grasp the information (position, shape, etc.) of the path shape T2p. The path shape T2p is the shape of the path of the controlled part 15s when the controlled part 15s moves along the corrected target shape T2, as described above.

[0076] [Example of path shape T2p E1] The path shape T2p displayed by the output unit 80 may also be the shape of the path of the controlled part 15s assuming that the controlled part 15s moved precisely (ideally, with an actual deviation E_real of 0) along the corrected target shape T2.

[0077] [Example of path shape T2p E2] The path shape T2p displayed by the output unit 80 may be the shape of the path (trajectory) of the controlled part 15s as it actually moved along the corrected target shape T2. For example, as in the above [Setting Example B2], the controller 70 may correct the target shape T so that the offset amount To approaches 0 according to the elapsed time of movement of the controlled part 15s in follow control. In this case, if the movement speed of the controlled part 15s is not predetermined (for example, if it is determined according to manual operation of the operation unit 61), the path of the controlled part 15s cannot be determined until after the controlled part 15s has actually moved. In this case, if the path of the controlled part 15s cannot be determined until after the controlled part 15s has actually moved, the path shape T2p displayed by the output unit 80 will be the shape of the path of the controlled part 15s as it actually moved along the corrected target shape T2.

[0078] The controller 70 may also display the pre-correction target shape T1 on the output unit 80. In this case, when the controlled part 15s moves along the corrected target shape T2, the operator looking at the output unit 80 can be made aware of the portion of the controlled part 15s that does not follow the pre-correction target shape T1.

[0079] (Display of region T2r) The controller 70 displays the region T2r between the path shape T2p shown in Figure 5 and the target shape T1 before correction (for example, the region in the following crossing direction W) on the output unit 80. In this case, the operator looking at the output unit 80 can grasp the information (position, shape, etc.) of the region T2r. For example, when excavation work is performed with follow control, this region T2r is the part where the work object G (see Figure 1) remains because it cannot be excavated in a single operation of the attachment 15 with follow control.

[0080] (Information about the next task) As described above, the controller 70 outputs the path shape T2p or region T2r to the output unit 80. This output allows the operator, by looking at the output unit 80, to understand the portion of the operation in the current follow-up control where the controlled part 15s did not move along the pre-correction target shape T1 (hereinafter referred to as the "unworkable portion"). As a result, the operator can understand the appropriate starting position for the next follow-up control. This "appropriate starting position for the next follow-up control" is the starting position of the follow-up control where the portion that could not be worked in the current follow-up control can be worked in the next follow-up control (the controlled part 15s follows the pre-correction target shape T1). For example, suppose the direction of movement of the attachment 15 in the current follow-up control (work progress side U2) is the front side X2. In this case, the controller 70 outputs the path shape T2p or region T2r to the output unit 80. This output prompts the operator to initiate the next tracking control at an appropriate position X1 further back than the starting position of the current tracking control.

[0081] The controller 70 may output (present) the "appropriate starting position for the next follow-up control" to the output unit 80. More specifically, the controller 70 may output to the output unit 80 the starting position for the next follow-up control such that the controlled part 15s moves along the pre-correction target shape T1 in the "part that could not be worked on" during the current follow-up control.

[0082] (Operation of the work machine 10 before the start of follow-up control) The operation of the work machine 10 before follow-up control is performed will be described below. Before follow-up control is performed, the work machine 10 may be moved by manual operation by an operator (onboard operation or remote operation), by semi-automatic operation, or by automatic operation.

[0083] (Stop control) The controller 70 may perform stop control before performing follow control. Stop control is a control that automatically stops the attachment 15 when the controlled part 15s (stop control target part) shown in Figure 3 reaches the target stop position P1. Stop control is a control that stops the attachment 15 when the attachment 15 is at a position away from the target shape T (on the opposite approach side W1) so that the attachment 15 does not exceed (enter) the target shape T. When excavation work is performed with follow control, stopping the controlled part 15s at the target stop position P1 can prevent the attachment 15 (for example, the controlled part 15s) from excavating beyond the pre-correction target shape T1 into the work object G (see Figure 1) (over-excavation).

[0084] The target stop position P1 is the target position where the controlled part 15s will be stopped. The target stop position P1 is set to a position on the opposite side W1 (the side moving from the target shape T1 towards the attachment 15) from the pre-correction target shape T1. The target stop position P1 is set to a position that is separated from the pre-correction target shape T1 by a predetermined stopping deviation Es on the opposite side W1. For example, in the example shown in Figure 3, the target stop position P1 is set to a position Z1 above the pre-correction target shape T1 (a higher position) by a stopping deviation Es.

[0085] The stopping deviation Es is set in the controller 70 in advance (before the stopping control is performed). The stopping deviation Es is set to the following magnitude, for example. Assume that the attachment 15 is approaching the target shape T at the assumed maximum speed while it has captured the workpiece G of the assumed maximum mass (see Figure 1) (for example, the workpiece G of the assumed maximum mass is in the bucket). Assume that when the controlled part 15s reaches the target stopping position P1 from this state, the attachment 15 is stopped with the maximum operating command. Even in this case, the stopping deviation Es is set so that the controlled part 15s does not exceed the pre-correction target shape T1. For example, the stopping deviation Es may be set based on test results.

[0086] This stopping deviation Es may be set (manually) based on the operator's operation of the input unit 60. The stopping deviation Es may also be set automatically by the controller 70 according to some condition (condition for determining the stopping deviation Es). The conditions for determining the stopping deviation Es may include information detected by the detection unit 40 (see Figure 2), for example, information about the work machine 10. Specifically, the conditions for determining the stopping deviation Es may include information about the moving speed of the attachment 15, and information about the mass (self-weight) of the attachment 15. The conditions for determining the stopping deviation Es may also include the load on the attachment 15. For example, the detection unit 40 may detect the amount (mass, volume, etc.) of the work object G captured by the attachment 15 shown in Figure 1, and the controller 70 may calculate the load on the attachment 15 from the detected amount of the work object G. Alternatively, for example, the detection unit 40 may detect the magnitude of the load acting on the actuator 30 (e.g., the height of the holding pressure), and the controller 70 may calculate the load on the attachment 15 from the detected magnitude of the load.

[0087] The target stopping position P1 shown in Figure 3 may be, for example, a surface (it may also be a target stopping surface). In this case, the target stopping position P1 may include one or more planes, or one or more curved surfaces (similar to the case where the target shape T is a surface). For example, if the target shape T is a surface, the target stopping position P1 may be a surface with the same shape as the target shape T, but shifted by a stopping deviation Es toward the anti-approach side W1.

[0088] In stop control, when the controller 70 stops the attachment 15, it may terminate the stop control and start follow control. Specifically, when the controlled part 15s (specifically, the part subject to stop control) is on the opposite side W1 from the target stop position P1, the controller 70 executes stop control and does not execute follow control. When the controlled part 15s (specifically, the part subject to stop control) reaches the target stop position P1, the controller 70 stops the attachment 15, terminates the stop control, and starts follow control. In this case, no interference (control interference) occurs between the stop control and the follow control.

[0089] For example, the part to be stopped and the part to be followed are the same part (controlled part 15s), and the target stop position P1 and the follow-up control start position P2 are the same position. In this case, the controller 70 switches between stop control and automatic control when the controlled part 15s reaches the follow-up control start position P2, which is the target stop position P1. Note that the target stop position P1 is a different position from the follow-up control start position P2. For example, the target stop position P1 may be a position W1 that is not approaching the follow-up control start position P2.

[0090] (Deceleration control) The controller 70 may perform deceleration control, limiting the speed of the attachment 15 according to the stopping position deviation F. Deceleration control may be included in the stopping control. The stopping position deviation F is the difference (deviation) of the controlled part 15s (more specifically, the stopping control target part) relative to the target stopping position P1. The stopping position deviation F may be a difference in distance or a difference in angle, similar to the deviation E described above.

[0091] For example, the controller 70 calculates a restricted operation command (restricted operation command (see Figure 8, described later)) to limit the speed of the attachment 15 according to the stopping position deviation F. This "operation command" is an command to move the attachment 15 (attachment operation command), and is a command that the controller 70 outputs to the drive control unit 17 (see Figure 2). The controller 70 limits the speed of the attachment 15 (increases the degree of restriction) as the controlled part 15s approaches the target stopping position P1. For example, the controller 70 may reduce the maximum value of the attachment speed by decreasing the maximum value of the attachment operation command as the controlled part 15s approaches the target stopping position P1. For example, the controller 70 may control the attachment 15 so that the controlled part 15s gradually decelerates as it approaches the target stopping position P1, and the controlled part 15s stops at the target stopping position P1. For example, as the controlled part 15s approaches the target stop position P1, the controller 70 may reduce the ratio of the attachment operation command output to the drive control unit 17 to the input amount of the attachment operation.

[0092] In deceleration control, the elements of the attachment 15 that the controller 70 limits the speed of (the elements subject to speed limiting in deceleration control) may be some or all of the elements of the attachment 15. For example, the elements subject to speed limiting in deceleration control are the elements of the attachment 15 that are moved (operated) when the controlled part 15s is brought closer to the target stop position P1. For example, if the controlled part 15s is brought closer to the target stop position P1 (lowered) by lowering the boom 15a (see Figure 1), then the boom 15a becomes the element subject to speed limiting in deceleration control. Also, for example, the elements subject to speed limiting in deceleration control may include elements that are manually operated when follow-up control is performed in semi-automatic operation (e.g., the arm 15b).

[0093] In the example shown in Figure 8 (see step S213), the controller 70 has a pre-set relationship (e.g., a map) between the deviation E (the difference between the pre-correction target shape T1 shown in Figure 3 and the controlled part 15s) and the limiting operation command. This relationship is set for each element of the attachment 15 (for each target of speed limiting in deceleration control). The limiting operation command is the operation command after limiting the original operation command. For example, the limiting operation command is the operation command after limiting the operation command corresponding to the amount of operation of the operator's control unit 61 (see Figure 2) (original operation amount). For example, the limiting operation command is the maximum value of the operation command according to the deviation E. The controller 70 calculates the limiting operation command based on the acquired deviation E and this relationship (map). In the example shown in Figure 8, the controller 70 does not limit the original operation command if the deviation E is greater than a certain value (predetermined deviation Ea). Also, the controller 70 limits the maximum value of the operation command if the deviation E is less than or equal to the predetermined deviation Ea and greater than or equal to the stopping deviation Es. In this case, the controller 70 reduces the limit operation command (the maximum value of the attachment operation command) as the deviation E decreases. In the example shown in Figure 8, when the deviation E is less than or equal to a predetermined deviation Ea and greater than or equal to the stopping deviation Es, the limit operation command is a linear function of the deviation E (the graph showing the relationship between the limit operation command and the deviation E is a straight line). However, the limit operation command does not have to be a linear function of the deviation E. The graph showing the relationship between the limit operation command and the deviation E may also be a curve.

[0094] The controller 70 selects the smaller of the two operation commands: the operation command corresponding to the operation input to the operation unit 61 (see Figure 2) (the original operation command) and the limiting operation command determined based on the deviation E (lower selection). The controller 70 determines the lower selection operation command to be output to the drive control unit 17 as the operation command (the operation command to actually move the attachment 15).

[0095] (Specific example of processing by controller 70) A concrete example of the processing performed by the controller 70 will be explained with reference to the flowcharts shown in Figures 7 and 8. Unless otherwise specified, the explanation will follow the order in which the controller 70 performs its operations. Note that the order of operations can be changed in various ways.

[0096] (Example of processing 1) Figure 7 shows a flowchart of Example 1 of the controller 70's processing. In Example 1, no stop control is performed, and as shown in Figure 3, the corrected target shape T2 is set so that the offset amount To approaches 0 as the movement distance of the controlled part 15s in the follow control increases (see [Setting Example B1] above). In the following, each step shown in Figure 7 will be explained with reference to Figure 7.

[0097] In step S11, the controller 70 sets the pre-correction target shape T1 as shown in Figure 3. As described above, the pre-correction target shape T1 may be set by the operator manually operating the input unit 60 (see Figure 2). The pre-correction target shape T1 may be pre-set in the controller 70, set automatically by the controller 70 according to certain conditions, or input to the controller 70 from an external storage device. Specifically, the controller 70 may set information about the shape of the pre-correction target shape T1, information about the position of the pre-correction target shape T1 (e.g., height), or information about the inclination angle if the pre-correction target shape T1 is an inclined surface.

[0098] In step S12, the controller 70 obtains the deviation E. Specifically, the controller 70 calculates the position (coordinates) of the controlled part 15s from the attitude detected by the attitude detection unit 50 (see Figure 2). Then, the controller 70 calculates (calculates) the deviation E of the controlled part 15s with respect to the pre-correction target shape T1.

[0099] In step S14, the controller 70 determines whether or not to start follow control. For example, the controller 70 may determine whether or not an operation to start follow control has been input to the input unit 60. Specifically, the controller 70 may determine whether or not the MC switch has been turned on. Alternatively, for example, the controller 70 may determine whether or not the controlled part 15s has reached the follow control start position P2. If the controller 70 determines to start follow control, it starts follow control and performs the process in step S21. If the controller 70 determines not to start follow control, it does not start follow control and performs the process in step S15.

[0100] In step S15, the controller 70 controls the operation of the attachment 15 manually. In this case, the attachment operation command is set to match the amount of operation (lever operation) performed by the operator on the control unit 61 (see Figure 2).

[0101] In step S21, the controller 70 corrects the target shape T. More specifically, the controller 70 corrects the target shape T according to the deviation E (deviation Et2 at the start of tracking control) at the start of tracking control t2 (for example, the moment the MC switch is turned on). In the example shown in Figure 7, the controller 70 corrects the target shape T so that the offset amount To approaches 0 as the movement distance of the controlled part 15s in tracking control increases (as in [Setting Example B1] above).

[0102] In step S22, the controller 70 calculates (calculates) the actual deviation E_real of the controlled part 15s with respect to the corrected target shape T2 shown in Figure 3 (a specific example of the calculation method is the same as the method for calculating the deviation E).

[0103] In step S23, the controller 70 calculates an attachment operation command (indicated as "ATT operation command" in the figure). The controller 70 calculates the operation command such that the larger the actual deviation E_real, the larger the operation command to move the controlled part 15s closer to the corrected target shape T2 (towards the approach side W2). In this example, the follow control is performed semi-automatically by arm operation. In this case, the controller 70 increases the operation command to move the boom 15a (boom operation command) the larger the actual deviation E_real. Specifically, the controller 70 performs proportional control, making the boom operation command proportional to the actual deviation E_real. In the example shown in Figure 7, the controller 70 uses the product of the proportional control constant (coefficient) Kp and the actual deviation E_real (Kp × E_real) as the boom operation command. When the follow control is performed semi-automatically by arm operation, the controller 70 may also calculate an operation command to move the tip attachment 15c (tip attachment operation command). Furthermore, when follow-up control is performed in semi-automatic operation, the operation command for the operation performed in semi-automatic operation (arm operation in this example) is the operation command corresponding to the amount of operation (lever operation amount) performed by the operator on the control unit 61 (see Figure 2).

[0104] After the processing in step S23 or step S15, the processing flow returns to the start. Note that the process of setting the target shape T (step S11) only needs to be performed once unless the target shape T is changed. Also, the controller 70 continues to calculate the deviation E until tracking control starts (repeats the processing in step S12). After tracking control starts, the controller 70 continues to calculate the actual deviation E_real (repeats the processing in step S22).

[0105] (Example of processing 2) Figure 8 shows a flowchart of Example 2 of the controller 70's processing. In Example 2, stop control is performed, and as shown in Figure 4, the corrected target shape T2 is set so that the offset amount To approaches 0 as the elapsed time of movement of the controlled part 15s in the follow control increases (see [Setting Example B2] above). The differences between Example 2 and Example 1 of the processing described above will be explained below. In the following, each step shown in Figure 8 will be explained with reference to Figure 8.

[0106] After processing in step S12, the controller 70 performs the processing in step S213. In step S213, the controller 70 performs deceleration control. As described above, the controller 70 calculates a limiting operation command according to the deviation E.

[0107] In step S214, the controller 70 determines whether or not to start follow control. Specifically, the controller 70 determines whether the following conditions are met: the deviation E is less than or equal to the stopping deviation Es, and an operation to start follow control has been input to the input unit 60 (for example, the MC switch is turned on). Note that "deviation E is less than or equal to the stopping deviation Es" means that the controlled part 15s shown in Figure 3 has reached the target stopping position P1. If the controller 70 determines to start follow control, it stops the attachment 15 (performs stop control), finishes the stop process, starts follow control, and performs the process in step S221. If the deviation E is greater than the stopping deviation Es, or if an operation to start follow control has not been input to the input unit 60, the controller 70 determines not to start follow control. If the controller 70 determines not to start follow control, it does not start follow control, performs the process in step S15, and operates the attachment 15 manually.

[0108] In step S221, the controller 70 corrects the target shape T. The controller 70 corrects the target shape T according to the deviation E at the start of the follow control t2 (for example, the moment the MC switch is turned on) (follow control start deviation Et2) (similar to step S21 in Example 1 of the process). In the example shown in Figure 8, the controller 70 corrects the target shape T so that the offset amount To approaches 0 as the elapsed time of movement of the controlled part 15s in the follow control increases. After that, the controller 70 performs the processes in steps S22 and S23 (similar to Example 1 of the process).

[0109] (Effects of the first invention) The effects of the control device 1 shown in Figure 1 are as follows. The control device 1 includes a controller 70 that performs follow-up control. Follow-up control is a control that automatically moves the attachment 15 of the work machine 10 so that a specific follow-up control target part (control target part 15s) of the attachment 15 moves along the target shape T. The controller 70 acquires the follow-up control start deviation Et2 shown in Figure 3. The follow-up control start deviation Et2 is the deviation E of the control target part 15s with respect to the target shape T at the start of follow-up control (follow-up control start time t2).

[0110] [Configuration 1-1] The controller 70 corrects the target shape T to the position of the controlled part 15s at the start of tracking control t2 based on the deviation Et2 at the start of tracking control. Alternatively, the controller 70 corrects the target shape T to a position between the controlled part 15s and the target shape T at the start of tracking control t2 based on the deviation Et2 at the start of tracking control.

[0111] [Configuration 1-2] The controller 70 corrects the target shape T so that the offset amount To approaches 0 as the operation of the attachment 15 in follow-up control progresses. The offset amount To is the difference between the target shape T after correction (target shape T2) and the target shape T before correction (target shape T1).

[0112] With the above configuration [1-1], the controlled part 15s is more likely to reach the corrected target shape T2 before it reaches the pre-correction target shape T1 (before time t5). Also, the movement of the attachment 15 is more likely to change before and after the controlled part 15s reaches the corrected target shape T2. Therefore, the need to abruptly change the movement of the attachment 15 at the moment the controlled part 15s reaches the pre-correction target shape T1 (the moment of time t5) can be suppressed. As a result, for example, it can be suppressed that the controlled part 15s exceeds the pre-correction target shape T1. With the above configuration [1-2], as the work of the attachment 15 in follow-up control progresses, the controlled part 15s can be moved along the pre-correction target shape T1 (the original target shape T). Therefore, the attachment 15 can be precisely controlled so that it moves along the target shape T (more specifically, the pre-correction target shape T1).

[0113] For example, if the work performed by the work machine 10 using follow-up control is an excavation operation to excavate a work object G (see Figure 1) (e.g., soil), then it is possible to prevent the attachment 15 from digging too far into the work object G beyond the pre-correction target shape T1. Therefore, the shape of the work object G can be made to conform accurately to the pre-correction target shape T1.

[0114] (Effects of the second invention) [Configuration 2] The controller 70 corrects the target shape T so that the offset amount To approaches 0 (zero) according to the distance traveled by the controlled part 15s in the follow-up control.

[0115] With the above [Configuration 2], the controlled part 15s, which moves by tracking control, can be gradually brought closer to the pre-correction target shape T1. Therefore, the need to abruptly change the movement of the attachment 15 at the moment the controlled part 15s reaches the pre-correction target shape T1 (the moment at time t5) can be further suppressed. As a result, the attachment 15 can be controlled with greater precision so that it moves along the target shape T.

[0116] (Effects of the third invention) [Configuration 3] The controller 70 corrects the target shape T so that the offset amount To approaches 0 (zero) according to the elapsed time of movement of the controlled part 15s in the follow-up control (see step S221 in Figure 8).

[0117] The following effect can be obtained with the above [Configuration 3]. In tasks where it is important to move the controlled part 15s shown in Figure 4 with high precision (for example, finishing work), the movement speed of the controlled part 15s is slowed down. With the above [Configuration 3], the slower the movement speed of the controlled part 15s (for example, a very slow operation), the smaller the distance the controlled part 15s moves from the start of the tracking control until the offset amount To becomes 0 (more specifically, the distance moved in the tracking direction U). Therefore, the controlled part 15s can be moved along the pre-correction target shape T1 over a wider range.

[0118] (Effects of the fourth invention) [Configuration 4] The control device 1 includes an output unit 80 (see Figure 2) that outputs information. The controller 70 causes the output unit 80 to display the shape of the path of the controlled part 15s (path shape T2p) when the controlled part 15s moves along the corrected target shape T2 shown in Figure 3.

[0119] With the above [Configuration 4], the path shape T2p of the controlled part 15s along the corrected target shape T2 can be understood by the operator by looking at the display on the output unit 80.

[0120] (Effects of the fifth invention) [Configuration 5] The control device 1 includes an output unit 80 (see Figure 2) that outputs information. The controller 70 causes the output unit 80 to display the path of the controlled part 15s (path shape T2p) when the controlled part 15s moves along the corrected target shape T2, and the region T2r (see Figure 5) between the pre-correction target shape T1 and the controlled part 15s.

[0121] As described in [Configuration 5] above, the region T2r between the path shape T2p and the pre-correction target shape T1 can be made known to the operator by looking at the display on the output unit 80. For example, when excavation work is performed with follow control, if the controlled part 15s moves along the corrected target shape T2, the attachment 15 cannot excavate the work object G (see Figure 1) along the pre-correction target shape T1, resulting in a portion (region T2r) where the work object G remains. In this case, the output unit 80 displays region T2r, allowing the operator who looks at the display on the output unit 80 to know where the work object G remains (region T2r).

[0122] (Effects of the sixth invention) [Configuration 6] The controller 70 sets the target stop position P1 at a position on the side (anti-approach side W1) from the pre-correction target shape T1 toward the attachment 15, rather than the pre-correction target shape T1. The controller 70 performs stop control. Stop control is a control that automatically stops the attachment 15 when a specific controlled part 15s (stop control target part) of the attachment 15 reaches the target stop position P1.

[0123] With the above [Configuration 6], the controlled part 15s is moved to approach the pre-correction target shape T1, and the attachment 15 stops when the controlled part 15s reaches the target stop position P1. Therefore, it is possible to suppress the controlled part 15s, which is the part to be stopped, from exceeding the pre-correction target shape T1. As a result, it is possible to suppress the controlled part 15s, which is the part to be followed, from exceeding the pre-correction target shape T1. For example, when excavation work is performed with follow-up control, it is possible to further suppress the attachment 15 from digging beyond the pre-correction target shape T1 into the work object G (see Figure 1) (over-excavation).

[0124] (Effects of the seventh invention) [Configuration 7] The controller 70 limits the speed of the attachment 15 according to the stop position deviation F, which is the deviation of the controlled part 15s (stop control target part) from the target stop position P1.

[0125] With the above configuration [7], the smaller the stopping position deviation F, the more the speed of the attachment 15 can be restricted. In this case, the controlled portion 15s of the attachment 15 can be reliably stopped at the target stopping position P1.

[0126] (Effects of the 8th Invention) [Configuration 8] When the controller 70 stops the attachment 15 with stop control, it terminates the stop control and starts follow control.

[0127] The above configuration [8] makes it possible to prevent control interference between follow control and stop control.

[0128] (modified version) The above embodiments (including modifications within the embodiments (hereinafter the same)) may be modified in various ways. For example, the number of components in the above embodiments may be changed, and some components may not be provided. For example, the arrangement of components may be changed. For example, the connections between components shown in Figure 2, etc., may be changed. For example, the inclusion relationships of components may be changed in various ways. For example, a component described as a subordinate component included in a higher-level component may not be included in this higher-level component, but may be included in other components. For example, what was described as multiple distinct elements may be treated as a single element. For example, what was described as a single element may be divided into multiple distinct elements. For example, each component may have only a part of each characteristic (function, arrangement, shape, operation, etc.).

[0129] For example, the order of steps in the flowcharts shown in Figures 7 and 8 may be changed, some steps may be omitted, and steps from different flowcharts may be combined. For example, various information (values, ranges, etc.) (e.g., target shape T) may be pre-set in the controller 70, or may be set by being read into the controller 70 from an external storage device. Various information may be set in the controller 70 based on information set by manual operation by the operator (operation of the input unit 60 (see Figure 2)). Various information may be set in the controller 70 based on information detected by the detection unit 40 (see Figure 2). For example, various information may not be changed, may be changed by manual operation, or may be automatically changed by the controller 70 according to some condition. For example, the controller 70 may perform substantially the same processing as the processing (calculation, judgment, etc.) of the above embodiment. For example, the mathematical formulas used in the processing, the processing procedures, and the information used in the processing can be changed in various ways. Specifically, the controller 70 may perform processing using information that can be converted into the various information used in the above embodiment. The processing performed by the controller 70 may be combined in various ways.

[0130] The control device 1 is configured to perform each of the operations described above. A control program may be set to cause a computer (controller 70) to execute the processes that cause each of the operations described above. A control method may be used to perform each of the operations described above. Each of the operations described above may be referred to as a "step" in the control program and control method described above. For example, the correction of the target shape T may be referred to as a "target shape correction step". [Explanation of Symbols]

[0131] 1. Control device 10 Working Machines 15 Attachments 15s Controlled parts (following control target parts, stop control target parts) 70 Controllers 80 Output section E deviation Et2 Deviation at the start of tracking control F Stop position deviation P1 Target stop position T Target shape T1 Target shape before correction (Target shape before correction) T2 Corrected target shape (corrected target shape) To offset amount

Claims

1. The device includes a controller that performs tracking control, which is a control that automatically moves the attachment so that a specific part of the attachment of the work machine moves along a target shape. The aforementioned controller, The deviation at the start of the tracking control, which is the deviation of the target part of the tracking control at the start of the tracking control with respect to the target shape, is obtained. Based on the deviation at the start of the tracking control, the target shape is corrected to the position of the part to be tracked at the start of the tracking control, or based on the deviation at the start of the tracking control, the target shape is corrected to a position between the part to be tracked at the start of the tracking control and the target shape. As the operation of the attachment in the tracking control progresses, the target shape is corrected so that the offset amount, which is the difference between the target shape before correction and the corrected target shape, approaches zero. Control device.

2. A control device according to claim 1, The controller corrects the target shape so that the offset amount approaches zero, according to the distance traveled by the target part in the tracking control. Control device.

3. A control device according to claim 1, The controller corrects the target shape so that the offset amount approaches zero, according to the elapsed time of movement of the target part in the tracking control. Control device.

4. A control device according to claim 1, It is equipped with an output unit that outputs information, The controller displays the shape of the path of the tracking target part as it moves along the corrected target shape on the output unit. Control device.

5. A control device according to claim 1, It is equipped with an output unit that outputs information, The controller causes the output unit to display the region between the path of the tracking target unit as it moves along the corrected target shape and the target shape before correction. Control device.

6. A control device according to claim 1, The aforementioned controller, The target stopping position is set to a position on the side of the target shape before correction that is toward the attachment, The system performs stop control, which is a control that automatically stops the attachment when a specific stop control target part of the attachment reaches the target stop position. Control device.

7. A control device according to claim 6, The controller limits the speed of the attachment according to the stop position deviation, which is the deviation of the part to be stopped relative to the target stop position. Control device.

8. A control device according to claim 6 or 7, When the controller stops the attachment using the stop control, it terminates the stop control and starts the follow control. Control device.

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