Control device for work machine

Abstract

Provided is a control device capable of operating a work machine in cooperation with an operator while performing appropriate work support according to the skill level of the operator. The control device includes a work operation device and a control unit. The control unit controls a work attachment by setting an input amount of a command input to a work drive device by changing each of a designation operation amount that is an operation amount corresponding to a designation operation by a worker and a support operation amount that is an operation amount of a support operation for moving the work attachment along a target motion according to an assist rate for supporting an operation of the worker, and setting the assist rate so that a difference between the target motion and an actual motion decreases from a detection result of the actual motion of the work attachment.

Description

TECHNICAL FIELD

[0001] The present invention relates to a device for controlling an operation of a work machine.BACKGROUND ART

[0002] Conventionally, in a work machine such as a hydraulic excavator, a device for supporting an operation of an operator is known. A hydraulic excavator includes a machine body and a work attachment that is movable relative to the machine body. The work attachment includes, for example, a boom, an arm, and a bucket. When the operator operates the work attachment, excavation work or the like is performed at a work site.

[0003] For example, Patent Literature 1 discloses a technique for supporting a hydraulic excavator according to an operation type of an operator who performs a specific operation. Specifically, in the technology, the hydraulic excavator includes an operation data acquisition unit, an acceleration-deceleration data specification unit, an evaluation data acquisition unit, an evaluation value calculation unit, an operation type determination unit, and a display control unit. The acceleration-deceleration data specification unit specifies acceleration data in an acceleration period and deceleration data in a deceleration period in operation data. The evaluation data acquisition unit acquires acceleration evaluation data and deceleration evaluation data. The evaluation value calculation unit calculates an acceleration evaluation value based on the acceleration evaluation data and calculates a deceleration evaluation value based on the deceleration evaluation data. The operation type determination unit determines the operation type of the operator based on the acceleration evaluation value and the deceleration evaluation value. The display control unit outputs an operation support image including support information associated with an operation type. An operation type of the operator is determined based on the acceleration evaluation value and the deceleration evaluation value, and the operator is notified of support information corresponding to the operation type. The support information is information for presenting a state of a machine body to be watched by the operator, and is information for indirectly improving a skill of a specifying operation.CITATION LISTPatent Literature

[0004] Patent Literature 1: JP 2022-25976 A In the control described in Patent Literature 1, the operation type of the operator is determined based on the acceleration evaluation value and the deceleration evaluation value, but it is not always possible to accurately determine a skilled person and a non-skilled person of the operator from the degrees of acceleration and deceleration when operating the work attachment. Therefore, there is a problem that it is not possible to obtain appropriate support for the operator.SUMMARY OF INVENTION

[0005] An object of the present invention is to provide a control device for a work machine capable of operating a work machine in cooperation with an operator while performing appropriate work support according to the skill level of the operator.

[0006] Provided by the present invention is a control device that controls a work machine including a work device and a work drive device capable of moving the work device so that the work device performs a predetermined work operation according to an input command. The control device includes a work operation device to which a designation operation is input, the designation operation being an operation for a worker to designate a motion of the work device, a target motion acquisition unit that acquires information regarding a target motion that is a target of a motion of the work device, an actual motion detection unit capable of detecting an actual motion that is an actual motion of the work device, and a control unit that controls the work device by setting an input amount of the command input to the work drive device by changing each of a designation operation amount that is an operation amount corresponding to the designation operation and a support operation amount that is an operation amount of a support operation for moving the work device along the target motion according to an operation support rate that is a rate of supporting an operation of the worker, the control unit setting the operation support rate so that a difference between the target motion and the actual motion decreases from a detection result of the actual motion.BRIEF DESCRIPTION OF DRAWINGS

[0007] FIG. 1 is a side view illustrating a hydraulic excavator that is an example of a work machine according to an embodiment of the present invention.

[0008] FIG. 2 is a block diagram illustrating a hydraulic circuit and a control unit mounted on the hydraulic excavator.

[0009] FIG. 3 is a block diagram illustrating operation assist processing performed by the control device of the work machine according to the embodiment of the present invention.

[0010] FIG. 4 is a flowchart illustrating operation assist processing performed by the control device of the work machine according to the embodiment of the present invention.

[0011] FIG. 5 is a flowchart illustrating a part of the operation assist processing in FIG. 4 in detail.

[0012] FIG. 6 is a schematic view illustrating a state in which the work machine performs earth leveling work.

[0013] FIG. 7 is a schematic view illustrating a state in which the work machine performs earth leveling work.

[0014] FIG. 8 is a schematic view illustrating a state in which the work machine performs earth leveling work.

[0015] FIG. 9 is a schematic view illustrating a state in which the work machine performs earth leveling work.

[0016] FIG. 10 is a graph illustrating an assist rate calculated by the control device of the work machine according to the embodiment of the present invention and corresponding to the skill level of an operator.

[0017] FIG. 11 is a graph illustrating transition of an assist rate of an operator having a middle skill level, calculated by the control device of the work machine according to the embodiment of the present invention.

[0018] FIG. 12 is a schematic diagram for describing a target input value according to a first modified embodiment of the present invention.

[0019] FIG. 13 is a flowchart corresponding to FIG. 5 in a second modified embodiment of the present invention.

[0020] FIG. 14 is a block diagram illustrating operation assist processing performed by a control device of a work machine according to the second modified embodiment of the present invention.

[0021] FIG. 15 is a graph illustrating skilled person data for describing a target input value according to a third modified embodiment of the present invention.DESCRIPTION OF EMBODIMENTS

[0022] A preferred embodiment of the present invention will be described with reference to the drawings.

[0023] FIG. 1 is a side view illustrating a hydraulic excavator 1 (work machine) according to the present embodiment. FIG. 2 is a block diagram illustrating a hydraulic circuit and a control unit mounted on the hydraulic excavator 1. A control device according to the present embodiment is mounted on the hydraulic excavator 1. The hydraulic excavator 1 includes a lower travelling body 10 capable of travelling on the ground G, an upper slewing body 12 mounted on the lower travelling body 10, a work attachment 14 (work device) mounted on the upper slewing body 12, and a work drive device.

[0024] The lower travelling body 10 and the upper slewing body 12 constitute a machine body that supports the work attachment 14. The upper slewing body 12 includes a slewing frame 16 and a plurality of elements mounted thereon. The plurality of elements includes an engine room 17 that houses an engine and a cab 18 that is a driver's room.

[0025] The work attachment 14 can perform an excavation work operation that is an operation for excavation work, a compaction work operation that is an operation for compaction work, and the like. The excavation work operation is an operation of excavating the ground or earth and sand, and the compaction work operation is an operation of solidifying the ground by moving a compaction work site along a construction surface while pressing the compaction work site included in the work attachment 14 against the construction surface, that is, while applying a compaction pressure to the construction surface.

[0026] The work attachment 14 includes a boom 21, an arm 22, and a bucket 24. The boom 21 has a boom foot which is a proximal end portion and a boom top which is a distal end portion on an opposite side. The boom foot is connected to the front end of the slewing frame 16 via a boom foot pin 23B so that the boom 21 can be raised and lowered with respect to the machine body, that is, can turn in a vertical direction. The arm 22 has an arm foot that is a proximal end portion and an arm top that is a distal end portion on the opposite side. The arm foot is connected to the distal end portion of the boom 21 via an arm foot pin 23A such that the arm 22 is rotatable in the vertical direction with respect to the boom 21. The bucket 24 is rotatably attached to the arm top via a bucket pin 23C so as to be rotatable in the vertical direction with respect to the arm 22.

[0027] The work drive device can move the work attachment 14 such that the work attachment 14 performs a predetermined work operation according to an input command. The work drive device includes a boom cylinder 26, an arm cylinder 27, and a bucket cylinder 28 illustrated in FIGS. 1 and 2. The boom cylinder 26 is a boom driver, is interposed between the upper slowing body 12 and the boom 21, and extends and contracts so as to rotate the boom 21 in a derricking direction with respect to the upper slewing body 12. The arm cylinder 27 is an arm driver, is interposed between the boom 21 and the arm 22, and extends and contracts so as to rotate the arm 22 with respect to the boom 21. The bucket cylinder 28 is a bucket driver, and extends and contracts so as to rotate the bucket 24 in the vertical direction with respect to the arm 22.

[0028] Each of the boom cylinder 26, the arm cylinder 27, and the bucket cylinder 28 is a telescopic hydraulic cylinder, and has a configuration similar to each other. Describing the arm cylinder 27 representatively, the arm cylinder 27 has a head side chamber and a rod side chamber on the opposite side thereof. When hydraulic oil is supplied to the head side chamber, the arm cylinder 27 extends to move the arm 22 in an arm pulling direction (a direction in which the arm top approaches the boom 21), and discharges the hydraulic oil in the rod side chamber. On the other hand, the arm cylinder 27 contracts when the hydraulic oil is supplied to the rod side chamber, moves the arm 22 in an arm pushing direction (direction in which the arm top is separated from the boom 21), and discharges the hydraulic oil in the head side chamber.

[0029] FIG. 2 illustrates a hydraulic circuit 30, a work operation device 40, a plurality of sensors, a control unit 80 electrically connected thereto, and the like mounted on the hydraulic excavator 1, and these include elements constituting the control device. The control unit 80 includes, for example, a microcomputer, and controls the operation of each element included in the hydraulic circuit 30.

[0030] In addition to the boom cylinder 26, the arm cylinder 27, and the bucket cylinder 28, the hydraulic circuit 30 includes a pump unit 32, a boom control valve 36, an arm control valve 37, a bucket control valve 38, a boom flow rate operation valve 76, an arm flow rate operation valve 77, and a bucket flow rate operation valve 78.

[0031] The pump unit 32 includes a plurality of hydraulic pumps, and the plurality of hydraulic pumps includes at least one main pump and a pilot pump. The plurality of hydraulic pumps is connected to an engine (not illustrated) as a drive source, and are driven by power output from the engine to discharge hydraulic oil.

[0032] The boom control valve 36 is interposed between the pump unit 32 and the boom cylinder 26, and opens and closes to change the direction and flow rate (boom flow rate) of the hydraulic oil supplied from the pump unit 32 to the boom cylinder 26. The boom control valve 36 is constituted by a pilot-operated direction switching valve including a boom raising pilot port and a boom lowering pilot port. When pilot pressure is input to the boom raising pilot port, the boom control valve opens to allow hydraulic oil to be supplied to a head side chamber of the boom cylinder 26 at a flow rate (boom raising flow rate) corresponding to the magnitude of the pilot pressure, and when pilot pressure is input to the boom lowering pilot port, the boom control valve opens to allow hydraulic oil to be supplied to a rod side chamber of the boom cylinder 26 at a flow rate (boom lowering flow rate) corresponding to the magnitude of the pilot pressure.

[0033] The arm control valve 37 is interposed between the pump unit 32 and the arm cylinder 27, and performs an opening / closing operation so as to change a direction and a flow rate (arm flow rate) of the hydraulic oil supplied from the pump unit 32 to the arm cylinder 27. The arm control valve 37 is constituted by a pilot-operated direction switching valve including an arm pulling pilot port and an arm pushing pilot port. When pilot pressure is input to the arm pulling pilot port, the arm control valve opens to allow hydraulic oil to be supplied to a head side chamber of the arm cylinder 27 at a flow rate (arm pulling flow rate) corresponding to the magnitude of the pilot pressure, and when pilot pressure is input to the arm pushing pilot port, the arm control valve opens so as to allow hydraulic oil to be supplied to a rod side chamber of the arm cylinder 27 at a flow rate (arm pushing flow rate) corresponding to the magnitude of the pilot pressure.

[0034] The bucket control valve 38 is interposed between the pump unit 32 and the bucket cylinder 28, and performs an opening / closing operation so as to change a direction and a flow rate (bucket flow rate) of hydraulic oil supplied from the pump unit 32 to the bucket cylinder 28. The bucket control valve 38 is constituted by a pilot-operated direction switching valve including a bucket excavation pilot port and a bucket opening pilot port. When pilot pressure is input to the bucket excavation pilot port, the bucket control valve opens to allow hydraulic oil to be supplied to a head side chamber of the bucket cylinder 28 at a flow rate corresponding to the magnitude of the pilot pressure, and when pilot pressure is input to the bucket opening pilot port, the bucket control valve opens to allow hydraulic oil to be supplied to a rod side chamber of the bucket cylinder 28 at a flow rate corresponding to the magnitude of the pilot pressure.

[0035] The boom flow rate operation valve 76 includes a boom raising flow rate operation valve and a boom lowering flow rate operation valve (not illustrated), each of which is constituted by an electromagnetic valve (for example, an electromagnetic proportional pressure reducing valve or an electromagnetic inverse proportional pressure reducing valve). The boom raising flow rate operation valve is interposed between the pilot pump and the boom raising pilot port of the boom control valve 36, and is opened to allow a pilot pressure having a magnitude corresponding to a boom raising command signal input from the control unit 80 to the boom raising flow rate operation valve to be input to the boom raising pilot port. Similarly, the boom lowering flow rate operation valve is interposed between the pilot pump and the boom lowering pilot port of the boom control valve 36, and is opened to allow a pilot pressure having a magnitude corresponding to a boom lowering command signal input from the control unit 80 to the boom lowering flow rate operation valve to be input to the boom lowering pilot port.

[0036] The arm flow rate operation valve 77 includes an arm pulling flow rate operation valve and an arm pushing flow rate operation valve (not illustrated), each of which is constituted by an electromagnetic valve (for example, an electromagnetic proportional pressure reducing valve or an electromagnetic inverse proportional pressure reducing valve). The arm pulling flow rate operation valve is interposed between the pilot pump and the arm pulling pilot port of the arm control valve 37, and is opened to allow a pilot pressure having a magnitude corresponding to an arm pulling command signal input from the control unit 80 to the arm pulling flow rate operation valve to be input to the arm pulling pilot port. Similarly, the arm pushing flow rate operation valve is interposed between the pilot pump and the arm pushing pilot port of the arm control valve 37, and is opened to allow a pilot pressure having a magnitude corresponding to an arm pushing command signal input from the control unit 80 to the arm pushing flow rate operation valve to be input to the arm pushing pilot port.

[0037] The bucket flow rate operation valve 78 includes a bucket excavation flow rate operation valve and a bucket opening flow rate operation valve (not illustrated), each of which is constituted by an electromagnetic valve (for example, an electromagnetic proportional pressure reducing valve or an electromagnetic inverse proportional pressure reducing valve). The bucket excavation flow rate operation valve is interposed between the pilot pump and the bucket excavation pilot port of the bucket control valve 38, and is opened to allow a pilot pressure having a magnitude corresponding to a bucket excavation command signal input from the control unit 80 to the bucket excavation flow rate operation valve to be input to the bucket excavation pilot port. Similarly, the bucket opening flow rate operation valve is interposed between the pilot pump and the bucket opening pilot port of the bucket control valve 38, and is opened to allow a pilot pressure having a magnitude corresponding to a bucket opening command signal input from the control unit 80 to the bucket opening flow rate operation valve to be input to the bucket opening pilot port.

[0038] The work operation device 40 receives a motion of the work attachment 14 and an input of a work operation (designation operation) for designating the motion speed thereof, and inputs a speed command signal corresponding to the work operation to the control unit 80. The work operation device 40 according to the present embodiment includes a boom operation device 46, an arm operation device 47, and a bucket operation device 48 illustrated in FIG. 2.

[0039] The boom operation device 46 includes a boom lever, generates a boom raising operation signal or a boom lowering operation signal corresponding to a boom operation applied to the boom lever, specifically, a boom raising operation and a boom lowering operation for moving the boom 21 in a boom raising direction and a boom lowering direction, respectively, and inputs the boom raising operation signal or the boom lowering operation signal to the control unit 80.

[0040] The arm operation device 47 includes an arm lever, and generates an arm pulling operation signal or an arm pushing operation signal corresponding to the arm operation given to the arm lever, specifically, an arm pulling operation and an arm pushing operation for moving the arm 22 in the arm pulling direction and the arm pushing direction, respectively, and inputs the arm pulling operation signal or the arm pushing operation signal to the control unit 80.

[0041] The bucket operation device 48 includes a bucket lever, generates a bucket excavation operation signal or a bucket opening operation signal corresponding to a bucket operation applied to the bucket lever, specifically, a bucket excavation operation and a bucket opening operation for moving the bucket 24 in a bucket excavation direction and a bucket opening direction, respectively, and inputs the bucket excavation operation signal or the bucket opening operation signal to the control unit 80.

[0042] The plurality of sensors includes a plurality of stroke sensors 66 to 68. The plurality of stroke sensors 66 to 68 is attached to the work attachment 14 in order to detect the posture of the work attachment 14, and are, specifically, a boom cylinder stroke sensor 66, an arm cylinder stroke sensor 67, and a bucket cylinder stroke sensor 68. These sensors detect stroke lengths of the boom cylinder 26, the arm cylinder 27, and the bucket cylinder 28, in other words, detect the relative position of a cylinder rod in a stroke direction with respect to a cylinder tube.

[0043] Each of the plurality of sensors generates a detection signal corresponding to the detected physical quantity, and inputs the detection signal to the control unit 80.

[0044] The hydraulic excavator 1 further includes an input unit 45 and a display unit 49.

[0045] The input unit 45 is arranged in the cab 18 and receives input of various types of information. As an example, the input unit 45 includes various input buttons, a switch, a touch panel included in the display unit 49, and the like. In particular, the input unit 45 is capable of receiving input of information to be referred to in operation assist processing described later, and receives input of a start signal or the like for starting the operation assist. In addition, the input unit 45 can perform contactless communication with an ID card carried by an operator (worker), and can also receive an input of an ID number (personal identification information) of the operator from the ID card. The received information is stored in the storage unit 804 of the control unit 80.

[0046] The display unit 49 is a liquid crystal display provided in the cab 18, and displays various types of information regarding the operation of the hydraulic excavator 1, a control result and a calculation result of the control device, and the like to inform the operator. At this time, the display unit 49 receives a predetermined display command signal from the control unit 80, and displays various types of information to inform the operator according to the display command signal. The information includes an assist rate indicating the skill level of the operator.

[0047] The control unit 80 includes a central processing unit (CPU), a read only memory (ROM) that stores a control program, a random access memory (RAM) used as a work area for the CPU, and the like. When the CPU executes a control program stored in the ROM, the control unit 80 functions to include functional units of a drive control unit 801, a target track determination unit 802 (target motion acquisition unit), an assist rate calculation unit 803, and a storage unit 804. These functional units have no substance and correspond to units of functions executed by the control program. Note that an entire or a part of the control unit 80 is not required to be provided in the hydraulic excavator 1, and may be disposed at a position different from the hydraulic excavator 1 in a case where the hydraulic excavator 1 is remotely controlled. Further, the control program may be transmitted from a server (management device), a cloud, or the like at a remote location to the control unit 80 in the hydraulic excavator 1 and executed, or the control program may be executed on the server or the cloud and various command signals generated may be transmitted to the hydraulic excavator 1.

[0048] The drive control unit 801 performs basic control based on operation command signals input from the boom operation device 46, the arm operation device 47, and the bucket operation device 48. The basic control includes generating a boom raising command signal or a boom lowering command signal for extending and contracting the boom cylinder 26 (that is, causing the boom 21 to perform a derricking operation) at a speed corresponding to the boom raising operation command signal or the boom lowering operation command signa and inputting the boom raising command signal or the boom lowering command signal to the boom flow rate operation valve 76, generating an arm pulling command signal or an arm pushing command signal for extending and contracting the arm cylinder 27 at a speed corresponding to the arm pulling operation command signal or the arm pushing operation command signal (that is, causing the arm 22 to perform a turning operation) and inputting the arm pulling command signal or the arm pushing command signal to the arm flow rate operation valve 77, and generating a bucket excavation command signal or a bucket opening command signal for extending and contracting the bucket cylinder 28 (that is, causing the bucket 24 to perform a turning operation) at a speed corresponding to the bucket excavation operation command signal or the bucket opening operation command signal and inputting the bucket excavation command signal or the bucket opening command signal to the bucket flow rate operation valve 78.

[0049] The target track determination unit 802 acquires information regarding a target motion which is a target of the motion of the work attachment 14 in operation assist processing described later. Specifically, the target track determination unit 802 acquires information regarding the destination (target value) of a distal end 25 of the bucket 24 of the work attachment 14. As an example, the operator inputs the target value through the input unit 45. Further, the target track determination unit 802 determines a track (target track) when the distal end 25 of the bucket 24 moves based on the acquired target value. The information on the target track also includes information regarding the posture of each of the boom 21, the arm 22, and the bucket 24 of the work attachment 14 that moves together with the distal end 25. Note that the target value and the target track may be input from the input unit 45 by the operator. In addition, it may be stored in the storage unit 804 in advance by teaching or the like.

[0050] The assist rate calculation unit 803 calculates an assist rate (operation support rate) corresponding to the current operator in the operation assist processing. The assist rate corresponds to a ratio between the amount of operation by the operator and the amount of operation by the control unit 80. In other words, the assist rate means an index indicating how much the control unit 80 supports the operation of the operator in the command for moving the work attachment 14 of the hydraulic excavator 1.

[0051] The storage unit 804 stores various parameters, thresholds, graphs, data, and the like referred to in the assist processing.<Operation Assist Processing>

[0052] Next, operation assist processing executed by the control unit 80 according to the present embodiment will be described. FIG. 3 is a block diagram illustrating operation assist processing performed by the control device of the hydraulic excavator 1 according to the present embodiment. In this control system, cooperative control is performed by an operation by an operator and a control unit 80 (PID controller C1) that supports the operation. Here, an assist rate k (rate of assisting the operation of the operator) by the PID controller is calculated using a known fictitious reference iterative tuning (FRIT) method according to an operation characteristic and an operation result of the operator. Since it is necessary to quantitatively express the operator in the FRIT method, the operation characteristic of the operator is quantitatively evaluated, and the operator is regarded as a PID controller C2 from the operation result.

[0053] In FIG. 3, the function of the control unit 80 that calculates the assist rate k is displayed as “shared management (cooperative control).” According to the assist rate k, an input amount of the command input by the drive control unit 801 (FIG. 2) of the control unit 80 to the boom flow rate operation valve 76, the arm flow rate operation valve 77, and the bucket flow rate operation valve 78 of the work drive device is defined as u(t). Note that, in the following description, the variable t means a variable related to time. An input (support operation amount) for the control unit 80 to move the work attachment 14 along a preset target motion (including a target value and a target track) so as to support the operation of the operator is defined as uc(t). Further, an operation amount by which the operator operates the boom operation device 46, the arm operation device 47, and the bucket operation device 48 (a designation operation amount corresponding to the designation operation) is defined as uh(t). Furthermore, a finished shape obtained as a result of actual movement of the work attachment 14 or a track of the distal end 25 of the bucket 24 is defined as y(t). An input u(t) finally input to the work drive device by the control unit 80 to control the work attachment 14 can be expressed by the following Formula 1 from the input uc(t) corresponding to the support operation amount and the operation amount uh(t) corresponding to the command operation of the operator.[Math⁢ 1]u⁡(t)=k·uc(t)+(1-k)⁢uh(t)(Formula⁢ 1)

[0054] In the present embodiment, the speed type I-PD control law is applied. The input uc(t) of the control unit 80 and the operator's operation amount uh(t) in FIG. 3 are expressed by the following Formulas 2 and 3, respectively.[Math⁢ 2]C1:Δ⁢uc(t)=KIc(t)⁢e⁡(t)-KPc(t)⁢Δ⁢y⁡(t)-KDc(t)⁢Δ2⁢y⁡(t)(Formula⁢ 2)[Math⁢ 3]C2:Δ⁢uh(t)=KIh(t)⁢e⁡(t)-KPh(t)⁢Δ⁢y⁡(t)-KDh(t)⁢Δ2⁢y⁡(t)(Formula⁢ 3)

[0055] Note that, in Formulas 2 and 3, KPc(t), KIc(t), KDc(t), and KPh(t), KIh(t), KDh(t) represent a proportional gain, an integral gain, and a differential gain at each time t of the control unit 80 and the operator, respectively.

[0056] Note that Δ is a difference operator and is defined by the following Formula 4.[Math⁢ 4]Δ:=1-z-1(Formula⁢ 4)

[0057] Further, Δu(t) on the left side of Formulas 2 and 3 is based on the following Formula 5.[Math⁢ 5]Δ⁢u⁡(t)=u⁡(t)-u⁡(t-1)(Formula⁢ 5)

[0058] Furthermore, u(t) input to the hydraulic excavator can be expressed by the following Formulas 6 and 7 based on the above Formulas 2 and 3.[Math⁢ 6]Δ⁢u⁡(t)=Δ⁢uh(t)+Δ⁢uc(t)(Formula⁢ 6)[Math⁢ 7]Δ⁢u⁢(t)={(1-k)⁢KIh(t)+kKIc(t)}⁢e⁡(t)-{(1-k)⁢KPh(t)+kKPc(t)}⁢Δ⁢y⁡(t)-{(1-k)⁢KDh(t)+kKDc(t)}⁢Δ2⁢y⁡(t)(Formula⁢ 7)

[0059] Here, e(t) included in Formulas 2, 3, and 7 is a control error, and is defined by the following Formulas 8 and 9 by a preset target value r(t) and a system output y(t). Note that, in order to calculate the assist rate k by the FRIT method, when the operator operates the work attachment 14 once, obtained data of the system output and the operation amount are defined as y0(t) and u0(t), respectively. Further, r~(t) is a pseudo reference input calculated from these data. (Note that, unlike each formula, in the present text, the reference sign of tilde is indicated by a superscript immediately after the target reference sign.)[Math⁢ 8]e⁡(t)=r~(t)-y0(t)(Formula⁢ 8)[Math⁢ 9]r⁡(t)=y0(t)+Δ(1-k)⁢KIh(t)+kKIc(t)⁢{u0(t)+{(1-k)⁢KPh(t)+kKPh(t)}⁢y0(t)+{(1-k)⁢KDh(t)+kKDc(t)}⁢Δ⁢y0(t)}(Formula⁢ 9)

[0060] Furthermore, the reference model is defined as the following Formulas 10, 11, and 12. Note that, in the present embodiment, the reference model is represented by a quadratic expression, but the reference model may be a linear expression or a polynomial expression. In Formula 10, d represents dead time and is known.[Math⁢ 10]Gm(z-1)⁢P⁡(1)P⁡(z-1)(Formula⁢ 10)[Math⁢ 11]P⁡(z-1)=1+p1⁢z-1+p2⁢z-2(Formula⁢ 11)[Math⁢ 12][p1=-2⁢exp⁢ (-ρ2⁢μ)⁢ cos⁢ (4⁢μ-12⁢μ⁢ρ)p2=exp⁢ (-ρμ)ρ:=Tsσμ:=0.25(1-δ)+0.51 δ(Formula⁢ 12)

[0061] Note that, in Formula 12, Ts represents sampling time, σ and δ represent a rising characteristic and an attenuation characteristic of the control system, respectively, and may be arbitrarily set in advance according to desired characteristics.

[0062] The above reference model corresponds to a system including a velocity component and an acceleration component as position components. Furthermore, a reference model output for the pseudo reference input r~(t) described above is defined as y~r(t), and can be expressed by the following Formula 13 using the reference model described above.[Math⁢ 13]yr~(t)=Gm(z-1)⁢r~(t)(Formula⁢ 13)

[0063] Further, in the FRIT method, an evaluation function J is defined as the following Formula 14. The assist rate calculation unit 803 calculates an assist rate k that minimizes the evaluation function J. In other words, the assist rate calculation unit 803 sets the assist rate k so that the difference between the target motion and the actual motion becomes small from the detection result of the actual motion corresponding to the designation operation. Note that N is the total number of steps of the input / output data in the target work.[Math⁢ 14]J=1N⁢∑((y0(t)-y˜(t)))2(Formula⁢ 14)

[0064] Note that the C1 controller is set to have desired response characteristics set in the above-described reference model. At this time, as the simplest method of setting the reference model, a response characteristic of a skilled person may be indicated by a transfer function as described later. In other words, the C1 controller is set so that the work attachment 14 is operated by an operation of a skilled person in a trial and error manner. On the other hand, the C2 controller is expressed by the above-described three gains using system identification or the like for the operation characteristic of the operator.

[0065] Further, the assist rate k that minimizes the evaluation function J is searched for using a known optimization method or the like. As a method of searching for the assist rate k, a general global search method such as a Nerder-Mead method or a genetic algorithm can be used. In addition, a local search method such as a steepest descent method may be used.<Flow of Operation Assist Processing>

[0066] FIG. 4 is a flowchart illustrating the operation assist processing. FIG. 5 is a flowchart illustrating a part of the operation assist processing of FIG. 4 in detail. FIGS. 6 to 9 are schematic diagrams illustrating how the hydraulic excavator 1 performs earth leveling work. Hereinafter, as an example, as illustrated in FIG. 6, it is assumed that there is a pile of earth and sand beside the hydraulic excavator 1, and work of scraping (leveling and excavating) a part of the earth and sand by the work attachment 14 is performed. In this case, the operator operates the arm 22 by himself / herself, and receives operation support by the control unit 80 for the operation of the boom 21. Note that it is assumed that the bucket 24 is relatively fixed to the arm 22. In this case, as illustrated in FIG. 6, the boom raising operation amount by the operator becomes the input u(t), and the boom 21 is appropriately driven and controlled by the operator and the control unit 80 according to the input u(t).

[0067] The operation assist processing is started, for example, in response to a start command signal input by the operator from the input unit 45. Note that the assist rate k is initially set to zero. When the operation assist processing is started, the target value r(t) (finished shape) is designated (step S1 in FIG. 4). In this case, the height of the pile after the earth and sand are excavated is designated as the target value r(t). The height may be input by the operator through the input unit 45.

[0068] Next, the target track determination unit 802 of the control unit 80 determines a target operation track y(t) of the work attachment 14 for achieving the target value r(t) (step S2 in FIG. 4). In FIG. 7, a track of the distal end 25 of the bucket 24 at this time is illustrated by a broken line. Further, in FIG. 4, a target operation track yr(t) until reaching the target value r(t) is simply drawn between step S1 and step S2. As described above, the target track determination unit 802 can calculate the target operation track yr(t) by Formula 13.

[0069] Next, the operator operates the work operation device 40 to perform work of excavating a part of the pile of earth and sand (step S3, FIG. 8). At this time, a message prompting the operation may be displayed on the display unit 49. Further, as described above, since the assist rate k is initially set to zero, the operation support by the control unit 80 is not performed, and the work attachment 14 is driven solely based on the operation of the operator.

[0070] The assist rate calculation unit 803 acquires the operation data y0(t) and u0(t) based on the motion of the work attachment 14 (step S4). That is, the data u0(t) of the operation amount when the operator operates the work operation device 40 and the data y0(t) related to a track of movement of the work attachment 14 according to the operation amount are acquired.

[0071] At this time, the assist rate calculation unit 803 calculates the posture of the work attachment 14 based on the cylinder strokes detected respectively by the stroke sensors 66 to 68, and acquires data regarding the track from the transition of coordinates of the distal end 25 of the bucket 24 in each posture. Note that, in the present embodiment, these stroke sensors 66 to 68 function as an actual motion detection unit. The actual motion detection unit can detect an actual motion which is an actual motion of the work attachment 14.

[0072] Note that, in FIG. 4, a temporal transition of each data is simply illustrated immediately below step S4. In addition, the sensors for detecting the posture of the work attachment 14, that is, the posture detection sensors are not limited to the stroke sensors 66 to 68 as described above. The posture detection sensors may include, for example, angle sensors that respectively detect a boom angle (a relative angle of the boom 21 with respect to the upper slewing body 12), an arm angle (a relative angle of the arm 22 with respect to the boom 21), and a bucket angle (a relative angle of the bucket 24 with respect to the arm 22), and a calculation unit that calculates a posture of the work attachment 14 based on the detected angle.

[0073] When the above data is acquired in step S4, the assist rate calculation unit 803 calculates the assist rate k based on the above formulas (step S5). At this time, in a case where the track of the work attachment 14 (the distal end 25 of the bucket 24) operated by the operator is close to the target track, a large operation support is unnecessary, and thus the assist rate k becomes small. On the other hand, when the track of the work attachment 14 operated by the operator is greatly deviated from the target track, large operation support is required, and thus the assist rate k increases.

[0074] Thereafter, the work is performed using the calculated assist rate k (step S6). That is, the calculated assist rate k is applied to the second excavation operation. Note that, at the start of the second excavation operation, each of the target value r(t) and the target operation track y(t) is newly set. At this time, the target value r(t) may be manually input, or may be automatically set based on preset work content. The work as described above is repeated, and the excavation of the pile of earth and sand ends as illustrated in FIG. 9.<Details of Calculation of Assist Rate k>

[0075] Next, the procedure of calculating the assist rate k in step S5 of FIG. 4 will be described in more detail with reference to FIG. 5. Note that step S11 in FIG. 5 corresponds to step S4 in FIG. 4. As described above, in the present embodiment, the input uc(t) of the control unit 80 and the operation amount uh(t) of the operator in FIG. 3 are defined as Formulas 2 and 3. Here, KPc(t), KIc(t), and KDc(t) in Formula 2 related to the controller C1 are calculated in advance and stored in the storage unit 804. On the other hand, KPh(t), KIh(t), KDh(t) in Formula 3 related to the controller C2 can be identified and determined by substituting the operation data acquired in step S11 (step S4 in FIG. 4) into Formula 3 and using a known least squares method, an optimization method, or the like (step S12 in FIG. 5) as in Formula 15 below.[Math⁢ 15]C2;Δ⁢uh0(t)=KIh(t)⁢e0(t)-KPh(t)⁢Δ⁢y0(t)-KDh(t)⁢Δ2⁢y0(t)(Formula⁢ 15)

[0076] Thereafter, as described above, the assist rate k that minimizes the evaluation function J expressed by Formula 14 is obtained (step S5 in FIG. 4 and step S13 in FIG. 5).

[0077] Note that, in the above described mode, KPh(t), KIh(t), KDh(t) in Formula 3 related to the controller C2 are calculated based on Formula 15, but these gains may be set in advance similarly to the controller C1. Table 1 is an example of each gain set in advance according to the skill level of the operator.TABLE 1KPhKIhKDhSkill Level: Middle1.00.0251.0Skill Level: Low①0.830.0150.89Skill Level: Low②0.750.0190.77

[0078] Table 1 illustrates data of operators extracted as subjects from among operators who actually operate the hydraulic excavator 1, and is a result of performing verification on a total of three subjects including two subjects with low skills (low skill levels) and one subject with medium skills (medium skill level), by roughly dividing the operation skills of the respective subjects into three known levels of low to high. Table 1 illustrates PID gains calculated in a boom lowering operation when a person is regarded as the controller C2. From Table 1, it can be seen that the value of the PID gain is higher in the subject with medium skills than in the subjects with low skills. In particular, the value of the integral gain of the subject with medium skills is twice the average value of the two subjects with low skills, and it can be seen that the operation with high followability is performed.

[0079] Note that, in the mode in which KPh(t), KIh(t), KDh(t) in Formula 3 are calculated based on Formula 15, a gain corresponding to an operator who actually operates the hydraulic excavator 1 is adopted, and thus, it is possible to calculate the assist rate k with high accuracy.<Display of Assist Rate k>

[0080] FIG. 10 is a graph illustrating the assist rate k according to the skill level of the operator calculated by the control device of the hydraulic excavator 1 according to the present embodiment, and illustrates a state in which the assist rate k changes every number of times of repeating the excavation operation of the pile of earth and sand as illustrated in FIGS. 6 to 9. Note that the three subjects illustrated in FIG. 10 correspond to Table 1 described above. As illustrated in FIG. 10, in the case of the operator at the medium skill level, the assist rate k changes around 60% in the second and subsequent works. On the other hand, in the case of the two operators with low skill levels, the assist rate k changes around 90% in the second and subsequent works. Thus, the degree of operation assistance is high for a subject with low skill requiring operation assistance, and the degree of operation assistance is relatively low for a subject with medium skill capable of performing work by himself / herself, and it is confirmed that the degree of operation assistance according to the skill of the operator can be automatically calculated by the operation assist processing according to the present embodiment.

[0081] FIG. 11 is a graph illustrating the transition of the assist rate k of the operator at the medium skill level calculated by the control device of the hydraulic excavator 1 according to the present embodiment up to the number of works longer than that in FIG. 10. As illustrated in FIG. 11, it can be seen that the assist rate k decreases as the operator at the medium skill level repeats the work. This means that, by getting used to the work, the skill is further improved, and the proportion that requires operation support is reduced.

[0082] Note that, by displaying graphs similar to FIGS. 10 and 11 as images on the display unit 49 (FIG. 2), the operator working on the hydraulic excavator 1 can grasp his / her own assist rate k. Furthermore, by confirming the transition of the assist rate k as illustrated in FIG. 11, it is also possible to confirm improvement of one's own skill and skill level.

[0083] As described above, in the present embodiment, the control unit 80 controls the work attachment 14 by setting the input amount of the command input to the work drive device by changing each of the designation operation amount and the support operation amount according to the assist rate k that is a rate of supporting the operation of the operator. In particular, the control unit 80 automatically sets the assist rate k according to the motion (actual motion) of the work attachment 14, so that it is possible to support the operation suitable for the skill level of the operator. Specifically, in a case where an unskilled person performs an operation significantly different from the target motion, the difference between the target motion and the actual motion increases, and thus the assist rate k also increases. As a result, the control of the operation of the hydraulic excavator 1 by the control unit 80 becomes strong, and even an unskilled person can perform the operation at ease. On the other hand, when the skilled person performs an operation that is the same as or close to the target motion, the difference between the target motion and the actual motion decreases, and thus the assist rate k decreases. As a result, the control of operation of the hydraulic excavator 1 by the control unit 80 is reduced, and a skilled operator can steer the hydraulic excavator 1 based on his / her own operation.

[0084] In particular, in the present embodiment, the assist rate k can be accurately calculated by regarding not only the support operation by the control unit 80 but also the designation operation by the operator as the PID controller.

[0085] Further, in the present embodiment, the hydraulic excavator 1 further includes the display unit 49 capable of displaying the assist rate k set by the control unit 80. With such a configuration, the operator can recognize his / her skill level by checking the assist rate k displayed on the display unit 49.

[0086] In particular, the display unit 49 can display the transition of the assist rate k set by the control unit 80 every time the designation operation is input to the work operation device 40. With such a configuration, by checking the transition of the assist rate k displayed on the display unit 49, the operator can recognize a change in his / her skill level (technique level) and the degree of improvement. In addition, the manager who manages the work can grasp the skill level of the operator and reflect the skill level in work instruction.

[0087] Further, in the present embodiment, the control unit 80 is configured to control at least the boom driver of the work drive device based on the assist rate k. With such a configuration, since the boom operation of the hydraulic excavator 1 can be assisted according to the assist rate k, for example, in ground leveling work and the like, the operator can perform the work focusing on the operation of the arm 22 and the bucket 24 other than the boom 21.

[0088] Although the control device of the hydraulic excavator 1 according to one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. The present invention includes, for example, the following modified mode.

[0089] (1) FIG. 12 is a schematic diagram for describing a target input value according to a first modified embodiment of the present invention. In the above embodiment, as illustrated in FIG. 6, the description has been given in a mode in which the height of the pile of earth after excavation is input as the target value r(t), but as illustrated in FIG. 12, the target value r(t) may be, for example, information of a plane including each component of length×width×height. In addition, an equation of a plane based on a coordinate system having a predetermined origin may be input as the target value r(t). Furthermore, the target value r(t) may be designated based on data at the time of instructing the motion of the hydraulic excavator 1 (work attachment 14) in machine control (automatic driving).

[0090] (2) FIG. 13 is a flowchart corresponding to FIG. 5 in a second modified embodiment of the present invention. FIG. 14 is a block diagram illustrating operation assist processing performed by the control device of the hydraulic excavator 1 according to the present modified embodiment. In the above embodiment, as illustrated in FIG. 3, the description has been given in a mode in which the operation of the operator is regarded as a controller based on the PID control law, but the present invention is not limited thereto. FIG. 13 is different from FIG. 5 in that step S12 does not exist. Steps S31 and S32 in FIG. 13 correspond to steps S11 and S13 in FIG. 5, respectively. In the present modified embodiment, the assist rate k can be calculated by using the following Formula 16 instead of the above-described Formula 9 without identifying the operation of the operator by the controller. Note that, in Formula 16, uno (t) is data when the operator performs an operation.[Math⁢ 16]r~(t)=y0(t)+ΔkKIc(t)⁢{u0(t)+(1-k)⁢uh⁢0(t)+kKPc(t)⁢y0(t)+kKDc(t)⁢Δ⁢y0(t)}(Formula⁢ 16)

[0091] Also in this case, as illustrated in the block diagram of FIG. 14, the controller C1 and the operator can operate in cooperation.

[0092] (3) FIG. 15 is a graph illustrating skilled person data for describing a target input value according to a third modified embodiment of the present invention. In the above embodiment, as illustrated in FIG. 6, the description has been given in a mode in which the height of the pile of earth after excavation is input as the target value r(t), but as illustrated in FIG. 15, the target value r(t) may be set using past operation data of a skilled person (operator with a low assist rate k) as a model.

[0093] In this case, the storage unit 804 of the control unit 80 desirably stores related information that is information in which personal identification information of an operator who operates the work attachment 14, information of a track (actual motion) of the distal end 25 of the work attachment 14 corresponding to a specific operator (specific worker) who is an operator having the personal identification information, and an assist rate k set for the specific operator are associated with each other. Then, the target track determination unit 802 may acquire, as the target value r(t) (information regarding the target motion), information of the track (response characteristic) of the distal end 25 of the specific operator having the assist rate k lower than the predetermined threshold among the related information.

[0094] With such a configuration, by setting the target value r(t) from the operation result of the specific operator corresponding to the skilled person, the skilled person can set the target value r(t) to the motion according to his / her preference. In addition, for an unskilled person, the target value r(t) can be set so as to target a skilled person.

[0095] (4) In the above embodiment, the description has been given in a mode in which the controllers C1 and C2 are defined based on a so-called I-PD control law in which only an integral gain acts on a control error as indicated in Formulas 2 and 3, but the present invention is not limited thereto. As in Formulas 17 and 18, the controllers C1 and C2 may be defined based on the so-called classical PID control law in which gains of proportion, integral, and derivative act on control errors.[Math⁢ 17]C1:Δ⁢uc(t)=KPc(t)⁢Δ⁢e⁡(t)-KIc(t)⁢e⁡(t)+KDc(t)⁢Δ2⁢e⁡(t)(Formula⁢ 17)[Math⁢ 18]C2:Δ⁢uh(t)=KPh(t)⁢Δ⁢e⁡(t)+KIh(t)⁢e⁡(i)+KDh(t)⁢Δ2⁢e⁡(t)(Formula⁢ 18)

[0096] In this case, the above-described Formulas 7 and 9 can be expressed as Formulas 19 and 20, respectively.[Math⁢ 19]Δ⁢u⁢(t)=Δ⁢uh⁢(t)+Δ⁢uc⁢(t)={(1-k)⁢KPh⁢(t)+kKPc⁢(t)}⁢Δ⁢e⁡(t)+{(1-k)⁢Kth(t)+kKIc(t)}⁢e⁡(t)+{(1-k)⁢KDh(t)+kKDc(t)}⁢Δ2⁢e⁡(t)(Formula⁢ 19)[Math⁢ 20]r~⁢(t)=y0⁢(t)+1{(1-k)⁢KPh(t)+kKPc(t)}+{(1-k)⁢KIh(t)+
kKIc(t)}+{(1-k)⁢KDh(t)+kKDc(t)}⁢Δ⁢u0⁢(t)+{(1-k)⁢KPh(t)+kKPc(t)}+2⁢{(1-k)⁢KDh(t)+
kKDc(t)}{(1-k)⁢KPh(t)+kKPc(t)}+{(1-k)⁢KIh(t)+
kKIc(t)}+{(1-k)⁢KDh(t)+kKDc(t)}⁢{r~(t-1)-y0(t-1)}-{(1-k)⁢KDh(t)+kKDc(t)}{(1-k)⁢KPh(t)+kKPc(t)}+{(1-k)⁢KIh(t)+
kKIc(t)}+{(1-k)⁢KDh(t)+kKDc(t)}⁢{r~(t-2)-y0(t-2)}(Formula⁢ 20)

[0097] (5) In the above embodiment, the description has been given in a mode in which the assist rate calculation unit 803 calculates the track of the distal end 25 of the bucket 24 to acquire the information regarding the actual motion of the work attachment 14, but the present invention is not limited thereto. The assist rate calculation unit 803 may acquire information regarding the actual motion of the work attachment 14 by directly detecting the state of a construction surface detected by light detection and ranging (LiDAR) or the like (actual motion detection unit) as a finished shape, and calculate the assist rate k.

[0098] (6) The work operation device 40 according to the present invention only needs to be provided with a work operation for designating the motion of the work attachment 14, and is not limited to one that converts the work operation into an electric signal like the operation devices 46 to 48. The work operation device 40 may be, for example, a valve that opens so as to allow the pilot pressure corresponding to the work operation to be input to a pilot-operated control valve connected to the work drive device, that is, a remote control valve. Also in this case, the designation operation amount corresponding to the work operation can be specified by detecting the pilot pressure output from the remote control valve by a pressure sensor and converting the detected pilot pressure into the designation operation amount.

[0099] (7) The assist target according to the above embodiment is a boom operation, but the assist target may be an arm operation or a bucket operation, or may be an operation of the entire work attachment 14.

[0100] (8) The work device according to the present invention is the work attachment 14, that is, a work device mounted on the hydraulic excavator 1, and is not limited to the work device including the boom 21, the arm 22, and the bucket 24.

[0101] (9) Note that, in the above description, (t) is added to the PID gains in Formulas 2, 3, 7, 9, and 15 to 20 so that time is a variable, but each gain may be a fixed value that does not change with time. That is, each gain may or may not change with time.

[0102] (10) Further, in the above embodiment, the description has been given in a mode in which the operator in the cab 18 operates the hydraulic excavator 1, but the present invention is not limited thereto. A device that remotely operates the hydraulic excavator 1 or a device that displays information of the hydraulic excavator 1 may be disposed separately from the hydraulic excavator 1. Also in this case, the control unit 80 can control the work attachment 14 by setting the input amount of the command input to the work drive device by changing each of the designation operation amount and the support operation amount according to the assist rate k that is a rate of supporting the operation of the operator.

[0103] As an example, the work operation device 40, the input unit 45, and the display unit 49 are provided in a remote control device separate from the hydraulic excavator 1. When the work operation device 40 receives an input of a work operation, a speed command corresponding to the work operation is input to the control unit 80 provided in the hydraulic excavator 1 via wireless communication. Similarly, when the input unit 45 receives an input of various types of information, the information is input to the control unit 80 provided in the hydraulic excavator 1 via wireless communication. The display unit 49 receives a display command signal input from the control unit 80 via wireless communication, and displays various types of information to be notified to the operator according to the display command signal.

[0104] Note that a device that performs remote control may be a remote control device or an information terminal such as a smartphone or a tablet. In addition, the information terminal is not limited to one that performs the remote operation, and may have only the functions of the input unit 45 and the display unit 49 that perform only fine adjustment of the machine and confirmation of the operation state of the machine externally for management and maintenance of the hydraulic excavator 1.

[0105] Provided by the present invention is a control device that controls a work machine including a work device and a work drive device capable of moving the work device so that the work device performs a predetermined work operation according to an input command. The control device includes a work operation device to which a designation operation is input, the designation operation being an operation for a worker to designate a motion of the work device, a target motion acquisition unit that acquires information regarding a target motion that is a target of a motion of the work device, an actual motion detection unit capable of detecting an actual motion that is an actual motion of the work device, and a control unit that controls the work device by setting an input amount of the command input to the work drive device by changing each of a designation operation amount that is an operation amount corresponding to the designation operation and a support operation amount that is an operation amount of a support operation for moving the work device along the target motion according to an operation support rate that is a rate of supporting an operation of the worker, the control unit setting the operation support rate so that a difference between the target motion and the actual motion decreases from a detection result of the actual motion.

[0106] With this configuration, the control unit automatically sets the operation support rate according to the actual motion, so that it is possible to support the operation corresponding to the skill level of the worker. Specifically, in a case where an unskilled person performs an operation significantly different from the target motion, the difference between the target motion and the actual motion increases, and thus the operation support rate also increases. As a result, the control of operation of the work machine by the control unit becomes strong, and even an unskilled person can perform the operation at ease. On the other hand, when the skilled person performs an operation that is the same as or close to the target motion, the difference between the target motion and the actual motion decreases, and thus the operation support rate decreases. As a result, the control of operation of the work machine by the control unit is reduced, and the skilled worker can operate the work machine based on his / her own operation.

[0107] In the above configuration, the control unit may control the work device by setting the input amount so as to satisfy a relationship of u(t)=k·uc(t)+(1−k)·uh(t), where t is a variable related to time, uh(t) is the designation operation amount, uc(t) is the support operation amount, k is the operation support rate, and u(t) is an input amount of the command input to the work drive device.

[0108] In the above configuration, the control unit may define the designation operation amount uh(t) and the support operation amount uc(t) by allocating each of a proportional gain, an integral gain, and a differential gain based on a PID control law to both the designation operation and the support operation.

[0109] With this configuration, the operation support rate can be accurately calculated by regarding not only the support operation by the control unit but also the designation operation by the worker as the PID controller.

[0110] In the above configuration, a display unit capable of displaying the operation support rate set by the control unit may be further included.

[0111] With this configuration, the worker can recognize his / her skill level by checking the operation support rate displayed on the display unit.

[0112] In the above configuration, the display unit may be capable of displaying a transition of the operation support rate set by the control unit each time the designation operation is input to the work operation device.

[0113] With this configuration, by checking the transition of the operation support rate displayed on the display unit, the worker can recognize a change in his / her skill level (technique level) and the degree of improvement. In addition, the manager who manages the work can grasp the skill level of the worker and reflect the skill level in work instruction.

[0114] In the above configuration, there may be further included a storage unit that stores related information that is information in which personal identification information of a worker who operates the work operation device, information on the actual motion corresponding to a specific worker who is a worker having the personal identification information, and the operation support rate set for the specific worker are associated with each other, in which the target motion acquisition unit may acquire, as information regarding the target motion, information of the actual motion of the specific worker with the operation support rate lower than a predetermined threshold in the related information.

[0115] With this configuration, by setting the target motion from the operation result of the specific worker corresponding to the skilled person, the skilled person can set the target motion to the motion according to his / her preference. Furthermore, for an unskilled person, a target motion can be set so that a skilled person is targeted.

[0116] In the above configuration, the work machine may be a hydraulic excavator, the hydraulic excavator may further include a machine body, the work device may include a boom connected to the machine body so as to be capable of being raised and lowered with respect to the machine body, an arm connected to the boom so as to be rotatable in a vertical direction with respect to the boom, and a bucket connected to a distal end portion of the arm, the work drive device may include a boom driver that raises and lowers the boom, and an arm driver that rotates the arm with respect to the boom, and the control unit may be configured to control at least the boom driver in the work drive device based on the operation support rate.

[0117] With this configuration, since the boom operation of the hydraulic excavator can be supported according to the operation support rate, for example, in ground leveling work and the like, the worker can perform the work focusing on the operation of the arm and the bucket other than the boom.

[0118] According to the present invention, there is provided a control device for a work machine capable of operating a work machine in cooperation with an operator while performing appropriate work support according to the skill level of the operator.

Claims

1. A control device for a work machine that controls the work machine including a work device and a work drive device capable of moving the work device so that the work device performs a predetermined work operation according to an input command, the control device comprising:a work operation device to which a designation operation is input, the designation operation being an operation for a worker to designate a motion of the work device;a target motion acquisition unit that acquires information regarding a target motion that is a target of a motion of the work device;an actual motion detection unit capable of detecting an actual motion that is an actual motion of the work device; anda control unit that controls the work device by setting an input amount of the command input to the work drive device by changing each of a designation operation amount that is an operation amount corresponding to the designation operation and a support operation amount that is an operation amount of a support operation for moving the work device along the target motion according to an operation support rate that is a rate of supporting an operation of the worker, the control unit setting the operation support rate so that a difference between the target motion and the actual motion decreases from a detection result of the actual motion.

2. The control device for the work machine according to claim 1, whereinthe control unit controls the work device by setting the input amount so as to satisfy a relationship of u(t)=k·uc(t)+(1−k)·uh(t), where t is a variable related to time, uh(t) is the designation operation amount, uc(t) is the support operation amount, k is the operation support rate, and u(t) is an input amount of the command input to the work drive device.

3. The control device for the work machine according to claim 2, whereinthe control unit defines the designation operation amount uh(t) and the support operation amount uc(t) by allocating each of a proportional gain, an integral gain, and a differential gain based on a PID control law to both the designation operation and the support operation.

4. The control device for the work machine according to claim 1, further comprising a display unit capable of displaying the operation support rate set by the control unit.

5. The control device for the work machine according to claim 4, whereinthe display unit is capable of displaying a transition of the operation support rate set by the control unit each time the designation operation is input to the work operation device.

6. The control device for the work machine according to claim 1, further comprising a storage unit that stores related information that is information in which personal identification information of a worker who operates the work operation device, information on the actual motion corresponding to a specific worker who is a worker having the personal identification information, and the operation support rate set for the specific worker are associated with each other, whereinthe target motion acquisition unit acquires, as information regarding the target motion, information of the actual motion of the specific worker with the operation support rate lower than a predetermined threshold in the related information.

7. The control device for the work machine according to claim 1, whereinthe work machine is a hydraulic excavator, the hydraulic excavator further includes a machine body, the work device includes a boom connected to the machine body so as to be capable of being raised and lowered with respect to the machine body, an arm connected to the boom so as to be rotatable in a vertical direction with respect to the boom, and a bucket connected to a distal end portion of the arm, the work drive device includes a boom driver that raises and lowers the boom, and an arm driver that rotates the arm with respect to the boom, and the control unit is configured to control at least the boom driver in the work drive device based on the operation support rate.

Images