Work machine control system, work machine control method, and remote control system for work machine

By installing a rotation judgment unit and an output unit on the working machine, the posture deviation of the rotating body is detected and corrected, the problem of unnecessary rotation of the rotating body during the working process is solved, and the stability and accuracy of the work are achieved.

JP2025019774APending Publication Date: 2025-02-07KOMATSU LTD
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Patent Information

Application Number
JP2023123581
Authority / Receiving Office
JP · JP
Patent Type
Applications
Current Assignee / Owner
Filing Date
2023-07-28
Publication Date
2025-02-07

AI Technical Summary

Technical Problem

When excavation and soil removal work is performed using working machinery with rotating bodies, the rotating body may rotate unanticipatedly, resulting in unbalanced loads and torques at the center of rotation, especially when working on slopes, which may cause rotation due to gravity, affecting the stability of the work.

Method used

A control system is adopted, which includes a rotation judgment unit and an output unit of the rotating body. By detecting the attitude deviation of the rotating body, the signal is output to prevent unnecessary rotation. The position and attitude calculation unit, the tilt measurement device, the working mechanical position identification unit and the control device are used to generate a target track and automatically adjust the attitude of the rotating body.

Benefits of technology

It effectively prevents unnecessary rotation of the working machine during the working process, ensures the stability and accuracy of the work, especially under automatic excavation control, and avoids accidental rotation of the rotating body.

✦ Generated by Eureka AI based on patent content.

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Abstract

To prevent occurrence of unintended revolution during work using a work machine.SOLUTION: A work machine control system determines whether or not a revolving body revolves when a work machine is operated while a revolving body is not operated. The control system outputs result of the determination whether or not the revolving body revolves.SELECTED DRAWING: Figure 1
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Description

[Technical field]

[0001] The present disclosure relates to a work machine control system, a work machine control method, and a work machine remote operation system. [Background technology]

[0002] Patent Document 1 discloses a technique relating to a work machine that performs automatic excavation processing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-041354 A Summary of the Invention [Problem to be solved by the invention]

[0004] Excavation work and soil removal work using a work machine equipped with a work implement supported on a rotating body are usually performed by driving the work implement without rotating the rotating body. However, depending on the environment, the rotating body may rotate even if the rotating body is not rotated during work. For example, when excavating using one side of a bucket, such as digging the wall of a trench, the load on the bucket becomes unbalanced between the left and right, and a moment is generated at the center of rotation of the rotating body that receives the reaction force, which may cause the rotating body to rotate. In addition, when the work machine is parked on a slope, a moment is generated due to gravity, which may cause the rotating body to rotate. An object of the present disclosure is to provide a work machine control system, a work machine control method, and a work machine remote operation system that are capable of preventing unintended turning during work. [Means for solving the problem]

[0005] According to one aspect of the present invention, a work machine control system is a work machine control system including a rotating body that can rotate around a rotation center and a work machine attached to the rotating body, and includes a rotation determination unit that identifies a deviation between the attitude of the rotating body and a reference attitude of the rotating body when the work machine is driving, and an output unit that outputs a signal related to the magnitude of the identified deviation. Effect of the Invention

[0006] According to the above aspect, the control system of the work machine can prevent unintended turning from occurring while the work machine is working. [Brief description of the drawings]

[0007] [Figure 1] 1 is a schematic diagram showing a configuration of a work machine according to a first embodiment. FIG. [Diagram 2] FIG. 2 is a diagram showing the internal configuration of a driver's cab according to the first embodiment. [Diagram 3] FIG. 2 is a schematic block diagram showing the configuration of a control device according to the first embodiment. [Figure 4] FIG. 4 is a diagram showing an example of a target trajectory according to the first embodiment; [Diagram 5] 3 is a flowchart showing an automatic excavation control method according to the first embodiment. [Figure 6] FIG. 11 is a diagram showing a configuration of a swing motor according to a second embodiment. [Figure 7] FIG. 13 is a diagram showing the configuration of a tilt rotate bucket according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, the embodiments will be described in detail with reference to the drawings. First Embodiment Configuration of the work machine 100 FIG. 1 is a schematic diagram showing the configuration of a work machine 100 according to a first embodiment. The work machine 100 according to the first embodiment performs automatic excavation control in accordance with instructions from an operator. Automatic excavation control is control that automatically executes an operation of driving the boom 131, arm 132, and bucket 133 to excavate earth and sand from a state in which the cutting edge of the bucket 133 is positioned at an excavation start position on an excavation target. In other words, in automatic excavation control, the work machine 100 drives the work implement 130 without outputting operation signals for the traveling body 110 and the rotating body 120. The work machine 100 operates at a construction site, excavates construction objects such as soil and sand, and loads the excavated objects as cargo onto a loading object such as a vessel or other loading platform, such as a dump truck. Examples of the work machine 100 include a face shovel, a backhoe shovel, and a rope shovel. The work machine 100 may be either electrically driven or hydraulically driven. The work machine 100 according to the first embodiment is a backhoe shovel. The work machine 100 includes a traveling body 110, a rotating body 120, a work implement 130, and a cab 140. Examples of the loading object include a dump truck and a hopper.

[0009] The running body 110 supports the work machine 100 so that it can run. The running body 110 includes two endless tracks 111 provided on the left and right, and two travel motors 112 for driving each of the endless tracks 111. The running body 110 is an example of a support portion. The rotating body 120 is supported by the running body 110 so as to be capable of rotating about a rotation center. The work machine 130 is hydraulically driven and supported on the front part of the revolving body 120 so as to be drivable in the vertical direction. The operator's cab 140 is a space where an operator rides in and operates the work machine 100. The operator's cab 140 is provided at the left front part of the rotating body 120. Here, the part of the rotating body 120 to which the work machine 130 is attached is referred to as the front part. Furthermore, with respect to the rotating body 120, the part opposite the front part is referred to as the rear part, the left part as the left part, and the right part as the right part.

[0010] Configuration of the rotating body 120 The rotating body 120 includes an engine 121, a hydraulic pump 122, a control valve 123, and a rotating motor 124. The engine 121 is a prime mover that drives the hydraulic pump 122. The engine 121 is an example of a power source. The hydraulic pump 122 is a variable displacement pump driven by the engine 121. The hydraulic pump 122 supplies hydraulic oil via a control valve 123 to each actuator (a boom cylinder 131C, an arm cylinder 132C, a bucket cylinder 133C, the traveling motor 112, and a swing motor 124). The control valve 123 controls the flow rate of the hydraulic oil supplied from the hydraulic pump 122 . The swing motor 124 is driven by hydraulic oil supplied from a hydraulic pump 122 via a control valve 123 to swing the swing body 120 .

[0011] Configuration of the work machine 130 The work machine 130 includes a boom 131, an arm 132, a bucket 133 as a work tool, a boom cylinder 131C, an arm cylinder 132C, and a bucket cylinder 133C. Other examples of the work tool include end attachments such as a clam bucket, a tilt bucket, a tilt rotate bucket, a grapple, and a lifting magnet.

[0012] The base end of the boom 131 is rotatably attached to the revolving body 120 via a boom pin. In the work machine 100 shown in FIG. 1, the boom 131 is provided at the center of the front of the revolving body 120, but the present invention is not limited to this and the boom 131 may be attached offset in the left-right direction. In this case, the center of rotation of the revolving body 120 is not located on the operating plane of the work implement 130. The arm 132 connects the boom 131 and the bucket 133. A base end of the arm 132 is rotatably attached to a tip end of the boom 131 via an arm pin. The bucket 133 is rotatably attached to the tip of the arm 132 via a pin. Members that support the bucket 133 include the boom 131 and the arm 132. The bucket 133 functions as a container for storing excavated soil and sand. The bucket 133 is attached so that its opening faces the rotating body 120 (rear). In other words, the work machine 100, which is a backhoe excavator, performs excavation by pulling the bucket 133 to the front side of the rotating body 120.

[0013] The boom cylinder 131C is a hydraulic cylinder for operating the boom 131. A base end of the boom cylinder 131C is attached to the rotating body 120. A tip end of the boom cylinder 131C is attached to the boom 131. The arm cylinder 132C is a hydraulic cylinder for driving the arm 132. A base end of the arm cylinder 132C is attached to the boom 131. A tip end of the arm cylinder 132C is attached to the arm 132. The bucket cylinder 133C is a hydraulic cylinder for driving the bucket 133. A base end of the bucket cylinder 133C is attached to the arm 132. A tip end of the bucket cylinder 133C is attached to a link mechanism that rotates the bucket 133.

[0014] Configuration of the cab 140 FIG. 2 is a diagram showing the internal configuration of the operator's cab 140 according to the first embodiment. A driver's seat 141, an operation terminal 142, and an operation device 143 are provided in the driver's cab 140. The operation terminal 142 is provided near the driver's seat 141, and is a user interface with a control device 160 described later. The operation terminal 142 is a display device formed of, for example, a touch panel, and may have an operation unit operated by an operator and an input receiving unit that receives operations. The display device also displays measurement data of an engine water temperature gauge, a fuel gauge, and the like. The operation terminal 142 may also be equipped with a display unit such as an LCD.

[0015] The operation device 143 is a device for driving the traveling body 110, the rotating body 120, and the work machine 130 by manual operation by an operator. The operation device 143 includes a left operation lever 143LO, a right operation lever 143RO, a left foot pedal 143LF, a right foot pedal 143RF, a left travel lever 143LT, a right travel lever 143RT, and a start switch 143SW.

[0016] The left operating lever 143LO is provided on the left side of the driver's seat 141. The right operating lever 143RO is provided on the right side of the driver's seat 141.

[0017] The left operation lever 143LO is an operation mechanism for performing the rotation operation of the revolving body 120 and the excavation / dumping operation of the arm 132. Specifically, when the operator of the work machine 100 tilts the left operation lever 143LO forward, the arm 132 performs the dumping operation. When the operator of the work machine 100 tilts the left operation lever 143LO rearward, the arm 132 performs the excavation operation. When the operator of the work machine 100 tilts the left operation lever 143LO to the right, the revolving body 120 rotates to the right. When the operator of the work machine 100 tilts the left operation lever 143LO to the left, the revolving body 120 rotates to the left. Note that in other embodiments, when the left operation lever 143LO is tilted in the front-rear direction, the revolving body 120 rotates to the right or left, and when the left operation lever 143LO is tilted in the left-right direction, the arm 132 performs the excavation operation or the dumping operation.

[0018] The right operation lever 143RO is an operation mechanism for performing an excavation / dump operation of the bucket 133 and a raising / lowering operation of the boom 131. Specifically, when the operator of the work machine 100 tilts the right operation lever 143RO forward, a lowering operation of the boom 131 is performed. When the operator of the work machine 100 tilts the right operation lever 143RO rearward, a raising operation of the boom 131 is performed. When the operator of the work machine 100 tilts the right operation lever 143RO to the right, a dump operation of the bucket 133 is performed. When the operator of the work machine 100 tilts the right operation lever 143RO to the left, an excavation operation of the bucket 133 is performed. Note that in other embodiments, when the right operation lever 143RO is tilted in the front-rear direction, the bucket 133 may perform a dump operation or an excavation operation, and when the right operation lever 143RO is tilted in the left-right direction, the boom 131 may perform a raising operation or a lowering operation.

[0019] The left foot pedal 143LF is disposed on the left side of the floor surface in front of the driver's seat 141. The right foot pedal 143RF is disposed on the right side of the floor surface in front of the driver's seat 141. The left travel lever 143LT is pivoted to the left foot pedal 143LF, and is configured so that the tilt of the left travel lever 143LT and the depression of the left foot pedal 143LF are linked. The right travel lever 143RT is pivoted to the right foot pedal 143RF, and is configured so that the tilt of the right travel lever 143RT and the depression of the right foot pedal 143RF are linked.

[0020] The left foot pedal 143LF and the left traveling lever 143LT correspond to the rotational drive of the left crawler belt of the traveling body 110. Specifically, when the operator of the work machine 100 pushes the left foot pedal 143LF or the left traveling lever 143LT forward, the left crawler belt rotates in the forward direction. Conversely, when the operator of the work machine 100 pushes the left foot pedal 143LF or the left traveling lever 143LT backward, the left crawler belt rotates in the reverse direction.

[0021] The right foot pedal 143RF and the right traveling lever 143RT correspond to the rotational drive of the right crawler belt of the traveling body 110. Specifically, when the operator of the work machine 100 pushes the right foot pedal 143RF or the right traveling lever 143RT forward, the right crawler belt rotates in the forward direction. Conversely, when the operator of the work machine 100 pushes the right foot pedal 143RF or the right traveling lever 143RT backward, the right crawler belt rotates in the reverse direction.

[0022] The start switch 143SW is provided, for example, on the handle portion of the left operation lever 143LO. The start switch 143SW may be disposed so as to be located near the operator seated in the driver's seat 141. When the start switch 143SW is operated, an excavation instruction signal is output to the control device 160. When the control device 160 receives the input of the excavation instruction signal, it starts automatic excavation control.

[0023] <<Configuration of the measurement system>> As shown in FIG. 1, the work machine 100 is equipped with a position and orientation calculator 151, an inclination measuring device 152, a boom stroke sensor 153, an arm stroke sensor 154, a bucket stroke sensor 155, and a shape detection device 156.

[0024] The position and orientation calculator 151 calculates the position of the revolving body 120 and the orientation in which the revolving body 120 faces. The position and orientation calculator 151 includes two receivers that receive positioning signals from artificial satellites that constitute the GNSS. The two receivers are installed at different positions on the revolving body 120. The position and orientation calculator 151 detects the position of a representative point of the revolving body 120 in the site coordinate system (the origin of the excavator coordinate system) based on the positioning signals received by the receivers. The position and orientation calculator 151 uses the positioning signals received by the two receivers to calculate the orientation of the revolving body 120 as the relationship between the installation position of one receiver and the installation position of the other receiver. The orientation of the revolving body 120 is a direction perpendicular to the front of the revolving body 120. The orientation of the revolving body 120 is equal to the horizontal component of the extension direction of a straight line extending from the boom 131 to the bucket 133 of the work machine 130.

[0025] The inclination measuring device 152 measures the acceleration and angular velocity of the rotating body 120, and detects the attitude (e.g., roll angle, pitch angle, yaw angle) and rotation speed of the rotating body 120 based on the measurement results. The inclination measuring device 152 is installed, for example, on the underside of the rotating body 120. The inclination measuring device 152 can use, for example, an inertial measurement unit (IMU).

[0026] The boom stroke sensor 153 is attached to the boom cylinder 131C and detects the cylinder length of the boom cylinder 131C. The cylinder length of the boom cylinder 131C can be converted into a relative angle of the boom 131 with respect to the revolving structure 120. The arm stroke sensor 154 is attached to the arm cylinder 132C and detects the cylinder length of the arm cylinder 132C. The cylinder length of the arm cylinder 132C can be converted into a relative angle of the arm 132 with respect to the boom 131. The bucket stroke sensor 155 is attached to the bucket cylinder 133C and detects the cylinder length of the bucket cylinder 133C. The cylinder length of the bucket cylinder 133C can be converted into a relative angle of the bucket 133 with respect to the arm 132. The work machine 100 according to the first embodiment identifies the angle of each link component of the work implement 130 using the boom stroke sensor 153, the arm stroke sensor 154, and the bucket stroke sensor 155, but other embodiments are not limited to this. For example, in other embodiments, instead of the stroke sensor, a potentiometer that detects the relative rotation angle of the link components may be provided, or an inclination sensor that detects the ground angle of each link component may be provided.

[0027] The shape detection device 156 detects the position and surface shape of an object present in the detection direction. Examples of the shape detection device 156 include a stereo camera and a laser scanner. The shape detection device 156 is provided so that the detection direction faces the front of the cab 140 of the work machine 100, for example. The shape detection device 156 identifies the surface shape of the object in a coordinate system based on the position of the shape detection device 156. Note that the shape detection device 156 according to another embodiment may identify the surface shape of the object based on the vehicle body coordinate system reference, based on dimensional values ​​of the mounting position of the shape detection device 156 measured in advance based on the vehicle body coordinate system reference. Also, the shape detection device 156 according to another embodiment may identify the surface shape of the object based on the site coordinate system reference, based on dimensional values ​​of the mounting position of the shape detection device 156 measured in advance based on the vehicle body coordinate system reference, and position and attitude information of the vehicle body in the site coordinate system.

[0028] Configuration of the control device 160 FIG. 3 is a schematic block diagram showing the configuration of the control device 160 according to the first embodiment. The work machine 100 includes a control device 160. The control device 160 may be implemented in the operation terminal 142, or may be provided separately from the operation terminal 142 and receive input and output from the operation terminal 142. The control device 160 receives an operation signal from the operation device 143. The control device 160 drives the work machine 130, the revolving body 120, and the traveling body 110 by outputting the received operation signal or an operation signal generated for automatic control to the control valve 123. Hereinafter, an operation signal received from the operation device 143 is also referred to as a manual operation signal, and an operation signal generated for automatic control is also referred to as an automatic operation signal. Note that the automatic operation signal is made up of an operation signal that drives the revolving body 120 and the work machine 130, and does not include an operation signal that drives the traveling body 110. When a manual operation signal by an operator is received during automatic control, the control device 160 may stop the automatic control.

[0029] The control device 160 is a computer including a processor 610, a main memory 630, a storage 650, and an interface 670. The storage 650 stores a program. The processor 610 reads the program from the storage 650, loads it into the main memory 630, and executes processing according to the program.

[0030] Examples of the storage 650 include a semiconductor memory, a magnetic disk, a magneto-optical disk, an optical disk, etc. The storage 650 may be an internal medium directly connected to a common communication line of the control device 160, or may be an external medium connected to the control device 160 via an interface 670. The main memory 630 and the storage 650 are non-transitory tangible storage media.

[0031] By executing a program, the processor 610 is equipped with a measurement data acquisition unit 611, an operation signal input unit 612, a work machine position identification unit 613, a trajectory generation unit 614, a movement control unit 615, a rotation determination unit 616, a rotation control unit 617, and an operation signal output unit 618.

[0032] The measurement data acquisition unit 611 acquires, for example, the rotation speed, position and direction of the rotating body 120, the inclination angles of the boom 131, the arm 132 and the bucket 133, the attitude of the rotating body 120, and the surface shape of the environment of the work machine 100. Note that the surface shape of the environment of the work machine 100 includes the surface shape of the excavation target.

[0033] The measurement data acquisition unit 611 acquires measurement data by the measurement system of the work machine 100. Specifically, the measurement data acquisition unit 611 acquires measurement data from the position and orientation calculator 151, the inclination measuring instrument 152, the boom stroke sensor 153, the arm stroke sensor 154, the bucket stroke sensor 155, and the shape detection device 156. The measurement data acquisition unit 611 calculates the angle of the revolving unit 120 by integrating the angular velocity of the revolving unit 120 measured by the inclination measuring instrument 152.

[0034] The operation signal input unit 612 receives an input of a manual operation signal manually operated by an operator from the operation device 143. The manual operation signals include a drive signal for performing a dumping operation or an excavation operation of the boom 131, a drive signal for performing a dumping operation or an excavation operation of the arm 132, a drive signal for performing a dumping operation or an excavation operation of the bucket 133, a drive signal for performing a right-turning operation or a left-turning operation of the rotating body 120, a drive signal for performing a traveling operation of the traveling body 110, and an excavation instruction signal for the work machine 100.

[0035] The work machine position identifying unit 613 identifies the position of the blade tip of the bucket 133 in the vehicle body coordinate system based on the revolving unit 120, based on the measurement data acquired by the measurement data acquiring unit 611. The work machine position identifying unit 613 determines the vertical and horizontal components of the length of the boom 131 based on the inclination angle of the boom 131 and the known length of the boom 131 (the distance from the pin at the base end to the pin at the tip end). Similarly, the work machine position identifying unit 613 determines the vertical and horizontal components of the length of the arm 132. Furthermore, the work machine position identifying unit 613 determines the vertical and horizontal components from the pin of the bucket 133 to the cutting edge based on the inclination angle of the bucket 133 and the known shape of the bucket 133. The work machine position identifying unit 613 identifies, as the position of the cutting edge of the bucket 133, a position that is away from the position of the work machine 100 in a direction identified from the orientation and posture of the work machine 100 by the sum of the vertical and horizontal components of the lengths of the boom 131, the arm 132, and the bucket 133.

[0036] The trajectory generating unit 614 generates a target trajectory T of the bucket 133 based on the position of the blade tip of the bucket 133 identified by the working machine position identifying unit 613 when the excavation command signal is input and the measurement data of the shape detecting device 156. FIG. 4 is a diagram showing an example of a target trajectory according to the first embodiment. The target trajectory T of the bucket 133 is drawn as a trajectory of the blade tip that excavates the excavation target in the excavation direction from the position of the blade tip of the bucket 133 when the excavation command signal is input. In the backhoe excavator, the excavation direction is the rearward direction of the rotating body 120. The shape of the target trajectory T according to the first embodiment is an arc. The target trajectory T is a target trajectory when excavation is performed by operating only the working machine 130 without a swing operation. The target trajectory T of the bucket 133 draws an arc related to a predetermined excavation curve ratio as shown in FIG. 4. The excavation curve ratio is a value (D / L) expressed as a ratio of the excavation depth D to the excavation length L. The smaller the excavation curve ratio, the longer the excavation length L and the shallower the excavation depth D. The larger the excavation curve ratio, the shorter the excavation length L and the deeper the excavation depth D. A method for specifying the excavation curve ratio will be described later. The trajectory generating unit 614 calculates the excavation amount when excavating according to the generated target trajectory T, and generates the target trajectory T of the bucket 133 so that the excavation amount is equal to the maximum capacity of the bucket 133. Note that the shape of the target trajectory T according to other embodiments may be any curve having a downward convex shape, such as an elliptical arc, a parabola, and a gentle curve without an inflection point. Note that the target trajectory T according to the first embodiment is a target trajectory when excavating by operating only the work machine 130 without a swing operation, but is not limited to this. The target trajectory T according to other embodiments may be a target trajectory when excavating while swinging at a constant swing speed. In this case, the target trajectory T may be a gentle curve without an inflection point.

[0037] The movement control unit 615 generates an automatic operation signal for moving the cutting edge of the bucket 133 along the target trajectory T when the operation signal input unit 612 accepts an input of an excavation instruction signal.

[0038] The rotation determination unit 616 determines whether or not an unintended rotation by the operator is occurring based on the difference between the orientation (reference attitude) of the rotating body 120 at the start of automatic excavation control measured by the position and orientation calculator 151 and the current orientation of the rotating body 120.

[0039] The rotation control unit 617 generates an automatic operation signal for rotating the rotating body 120 in the direction opposite to the direction of rotation when an unintended rotation by the operator occurs. The rotation control unit 617 is an example of an output unit that outputs a signal related to the magnitude of deviation between the attitude of the rotating body 120 and a reference attitude. The attitude of the rotating body 120 is the orientation of the rotating body 120.

[0040] The operation signal output unit 618 outputs a manual operation signal input to the operation signal input unit 612, an automatic operation signal generated by the movement control unit 615, or an automatic operation signal generated by the rotation control unit 617. Specifically, the operation signal output unit 618 outputs the automatic operation signal generated by the movement control unit 615 and the rotation control unit 617 when automatic excavation control is in progress, and outputs the manual operation signal input to the operation signal input unit 612 when automatic excavation control is not in progress.

[0041] 《Operation》 When the operator of the work machine 100 moves the blade tip of the bucket 133 to the excavation start position, he or she operates the start switch 143SW. This causes the operation device 143 to generate and output an excavation command signal. The excavation start position is a position on the surface of the excavation target.

[0042] When the control device 160 receives an input of an excavation command signal from the operator, the control device 160 first generates a target trajectory T for the bucket 133. Specifically, the control device 160 generates the target trajectory T in the following procedure. First, the measurement data acquisition unit 611 acquires measurement data relating to the position and orientation of the revolving unit 120, the relative angles of the boom 131, the arm 132, and the bucket 133, the attitude of the revolving unit 120, and the surface shape of the excavation target. The work machine position identification unit 613 identifies the position of the blade tip of the bucket 133 at the time of input of the excavation command signal based on the measurement data acquired by the measurement data acquisition unit 611. The trajectory generation unit 614 generates a target trajectory T of the bucket 133 that passes through the position of the blade tip identified by the work machine position identification unit 513 and such that the excavation amount is equal to the maximum capacity of the bucket 133. At this time, the rotation determination unit 616 also records in the main memory 630 the orientation of the revolving unit 120 at the time of input of the excavation command signal.

[0043] 5 is a flowchart showing the automatic excavation control method according to the first embodiment. When the target trajectory is generated, the control device 160 executes the automatic excavation control shown in FIG.

[0044] The measurement data acquisition unit 611 acquires measurement data relating to the position and orientation of the revolving unit 120, the relative angles of the boom 131, the arm 132, and the bucket 133, the attitude of the revolving unit 120, and the surface shape of the excavation target (step S1). The work machine position identification unit 613 identifies the position of the blade tip of the bucket 133 at the time of input of the excavation command signal based on the measurement data acquired by the measurement data acquisition unit 611 (step S2). The movement control unit 615 determines the target position of the blade tip of the bucket 133 and the target attitude of the bucket 133 based on the target trajectory T and the position of the blade tip of the bucket 133 (step S3).

[0045] The movement control unit 615 determines the target position and target attitude of the boom 131 and the arm 132 based on the target position of the cutting edge and the target attitude of the bucket 133 (step S4). For example, the movement control unit 615 can specify the position of the tip of the boom 131, i.e., the position of the base end of the arm 132, for moving the cutting edge of the bucket 133 to the target position, based on the relationship between the position of the base end of the bucket 133 specified from the target position of the cutting edge and the target attitude of the bucket 133 and the known position of the base end of the boom 131. The movement control unit 615 generates an automatic operation signal for the work machine 130 based on the specified target positions and target attitudes of the boom 131, the arm 132, and the bucket 133 (step S5).

[0046] The rotation determination unit 616 calculates the angle (rotation angle) of the difference between the orientation of the rotating body 120 indicated by the measurement data acquired from the position and orientation calculator 151 in step S1 and the orientation of the rotating body 120 at the time of input of the excavation instruction signal recorded in the main memory 630 (step S6).

[0047] The turning determination unit 616 determines whether or not the absolute value of the calculated turning angle exceeds a predetermined turning angle threshold (step S7). The turning angle threshold may be set in consideration of the measurement error of the position and orientation calculator 151. If the absolute value of the turning angle does not exceed the turning angle threshold (step S7: NO), the turning determination unit 616 determines that no turning unintended by the operator has occurred. If it is determined that no turning unintended by the operator has occurred, the operation signal output unit 618 outputs the automatic operation signal generated by the movement control unit 615 in step S5 to the control valve 123 (step S8). As a result, the work machine 130 moves along the target trajectory T.

[0048] On the other hand, if the absolute value of the turning angle exceeds the turning angle threshold value (step S7: YES), the turning determination unit 616 determines that a turning unintended by the operator is occurring. If it is determined that an unintended turn by the operator has occurred, the turn control unit 617 generates an automatic operation signal for turning the turning body 120 in the direction opposite to the direction in which the turn occurred, based on the turn angle calculated in step S6 (step S9). The turn control unit 617 increases the control amount of the automatic operation signal as the absolute value of the turn angle increases.

[0049] The operation signal output unit 618 outputs the automatic operation signal generated by the movement control unit 615 and the automatic operation signal generated by the rotation control unit 617 to the control valve 123 (step S10). As a result, the work machine 130 moves along the target trajectory T, and the rotating body 120 rotates so as to cancel out the rotation unintended by the operator.

[0050] The movement control unit 615 determines whether or not the position of the blade tip of the bucket 133 is located at the end point of the target trajectory T (step S11). If the position of the blade tip of the bucket 133 is not located at the end point of the target trajectory T (step S11: NO), the control device 160 returns the process to step S1 and determines the next target position and target attitude of the work machine 130. On the other hand, if the position of the blade tip of the bucket 133 is located at the end point of the target trajectory T (step S11: YES), the control device 160 ends the automatic excavation control.

[0051] Actions and Effects In this way, the control device 160 of the work machine 100 according to the first embodiment determines whether the rotating body 120 is rotating during automatic excavation control, and if it is determined that the rotating body 120 is rotating, outputs a control signal to rotate the rotating body 120 in the direction opposite to the direction in which the rotating body 120 rotates. Automatic excavation control is control in which the work machine 100 does not output operation signals for the running body 110 and the rotating body 120, but drives the work implement 130. This enables the control device 160 to cancel any rotation of the rotating body 120 that is not intended by the operator.

[0052] The control device 160 according to the first embodiment uses the orientation of the revolving body 120 indicated by the measurement data of the position and orientation calculator 151 to compare the attitude of the revolving body 120 at the start of the automatic excavation control with the attitude of the revolving body 120 during the automatic excavation control, but is not limited to this. For example, the control device 160 according to another embodiment may use an integrated value of the angular velocity of the revolving body 120 indicated by the measurement data of the inclination measuring device 152 after the start of the automatic excavation control to compare the attitude of the revolving body 120 at the start of the automatic excavation control with the attitude of the revolving body 120 during the automatic excavation control. Furthermore, the control device 160 according to another embodiment may use an integrated value of the measurement value of an encoder (not shown) provided on the revolving body to compare the attitude of the revolving body 120 at the start of the automatic excavation control with the attitude of the revolving body 120 during the automatic excavation control. Furthermore, in the case of automatically moving the work machine 130 while automatically rotating at a constant rotation speed under automatic control, the control device 160 may compare the ideal posture of the rotating body 120 when rotating according to the target rotation speed with the actual posture of the rotating body 120 when rotating at the measured actual rotation speed. For example, the control device 160 may determine the posture of the rotating body 120 based on whether or not an integrated value of the difference between the target rotation speed and the actual rotation speed exceeds a threshold value.

[0053] Second Embodiment The control device 160 according to the first embodiment judges whether the revolving body 120 is revolving or not by comparing the posture of the revolving body 120 at the start of the automatic excavation control with the posture of the revolving body 120 during the automatic excavation control. In contrast, the control device 160 according to the second embodiment judges whether the revolving body 120 is revolving or not based on the measured value of the pressure of the hydraulic oil of the revolving motor 124 after the start of the automatic excavation control.

[0054] FIG. 6 is a diagram showing the configuration of a rotation motor 124 according to the second embodiment. The swing motor 124 is connected to the control valve 123. The work machine 100 according to the second embodiment is provided with a pressure gauge 157 for measuring the pressure of hydraulic oil at each of the two ports of the swing motor 124. The swing direction of the swing motor 124 is determined by the valve position of the control valve 123. When the control valve 123 is in the neutral position, hydraulic oil is not supplied to the swing motor 124. At this time, when the swing motor 124 rotates due to an external action, the internal pressure of the two ports of the swing motor 124 changes. Therefore, the control device 160 can determine whether the swing body 120 is swinging or not based on the difference between the measured values ​​of the two pressure gauges 157. As shown in FIG. 7, the hydraulic circuit is provided with a check valve for preventing the internal pressure of the two ports from becoming negative pressure, and a relief valve for preventing an excessive rise in the internal pressure due to an external action.

[0055] The rotation determination unit 616 according to the second embodiment calculates the differential pressure between the ports of the rotation motor 124 based on the difference in measurement data acquired from the two pressure gauges 157. The rotation determination unit 616 determines that an unintended rotation by the operator is occurring when the absolute value of the differential pressure between the ports of the rotation motor 124 exceeds a predetermined differential pressure threshold. In addition, the rotation determination unit 616 can specify the rotation direction of the rotation motor 124 based on the sign of the differential pressure. When it is determined that an unintended rotation by the operator has occurred, the rotation control unit 617 generates an automatic operation signal for rotating the rotating body 120 in the direction opposite to the direction in which the rotation has occurred, based on the calculated differential pressure. The larger the absolute value of the differential pressure, the larger the control amount of the automatic operation signal that the rotation control unit 617 increases.

[0056] Actions and Effects In this way, the control device 160 of the work machine 100 according to the second embodiment determines whether or not the revolving body 120 is revolving during automatic excavation control, and when it is determined that the revolving body 120 is revolving, outputs a control signal for revolving the revolving body 120 in the direction opposite to the direction in which the revolving body 120 is revolving. As a result, the control device 160 according to the second embodiment can cancel out any unintended rotation of the revolving body 120 by the operator, as in the first embodiment.

[0057] The control device 160 according to the first embodiment determines whether the rotating body 120 is rotating by using the pressure difference between the ports of the rotation motor 124, but is not limited to this. For example, the control device 160 according to another embodiment may measure the flow speed of the hydraulic oil in the rotation motor 124 and determine whether or not the rotating body 120 is rotating based on the flow speed. In this case, the control device 160 can specify the direction of rotation based on the flow direction of the hydraulic oil.

[0058] Third Embodiment The work machine 100 according to the first embodiment is provided with a bucket 133 as a working implement. In contrast, the control device 160 according to the third embodiment is provided with a tiltrotating bucket having a tiltrotator 134 and a bucket 133 as a working implement.

[0059] FIG. 7 is a diagram showing the configuration of a tilt rotate bucket according to the third embodiment. The tilt rotator 134 is attached to the tip of the arm 132 so as to support the bucket 133. The tilt rotator 134 includes a mounting portion 1341, a tilt portion 1342, and a rotating portion 1343. The mounting portion 1341 is attached to the tip of the arm 132 so as to be rotatable around an axis extending in the left-right direction in the figure. The tilt portion 1342 is attached to the mounting portion 1341 so as to be rotatable around an axis extending in the front-rear direction in the figure. The rotating portion 1343 is attached to the tilt portion 1342 so as to be rotatable around an axis extending in the up-down direction in the figure. Ideally, the rotation axes of the mounting portion 1341, the tilt portion 1342, and the rotating portion 1343 are mutually orthogonal. The base end portion of the bucket 133 is fixed to the rotating portion 1343. This allows the bucket 133 to rotate around three axes mutually orthogonal to the arm 132. However, in reality, the rotation axes of the mounting portion 1341, tilt portion 1342, and rotating portion 1343 may include design errors and may not necessarily be perpendicular. On the other hand, at least the rotation axis of the tilt portion 1342 and the rotation axis of the rotating portion 1343 intersect with the rotation axis of the work machine 130 (the rotation axis of the mounting portion 1341). The rotation axis of the mounting portion 1341 is an example of the first axis, and the rotation axis of the tilt portion 1342 and the rotation axis of the rotating portion 1343 are an example of the second axis.

[0060] In a work machine 100 equipped with a tilt rotate bucket, when excavating using one side of the bucket 133, such as digging the wall of a trench, the load on the bucket 133 becomes unbalanced between the left and right sides, and a moment is generated not only about the rotating body 120 but also about the rotation axes of the tilt section 1342 and the rotating section 1343, which may cause the tiltrotator 134 to rotate.

[0061] The tilt rotator 134 according to the third embodiment includes a tilt encoder 1344 that measures the rotation angle of a tilt section 1342 about its rotation axis, and a rotate encoder 1345 that measures the rotation angle of a rotating section 1343 about its rotation axis. Based on the measurement data of tilt encoder 1344 and rotary encoder 1345, control device 160 determines whether the rotation angles of tilt unit 1342 and rotation unit 1343 exceed a predetermined threshold value, and determines whether rotation unintended by the operator is occurring in tilt unit 1342 or rotation unit 1343.

[0062] If it is determined that rotation unintentional by the operator has occurred, the control device 160 generates an automatic operation signal for rotating the tilt rotator 134 in the direction opposite to the direction in which the rotation occurred, based on the measurement data of the tilt encoder 1344 and the rotation encoder 1345.

[0063] Actions and Effects In this way, the control device 160 according to the third embodiment determines whether or not the tiltrotator 134 is rotating during automatic excavation control. This allows the control device 160 to prevent unintended rotation of the tiltrotator 134 while the work machine 100 is working. Note that the work machine 100 according to other embodiments may be equipped with a tilt bucket or a rotating bucket instead of the tilt rotating bucket.

[0064] Other Embodiments Although one embodiment has been described in detail above with reference to the drawings, the specific configuration is not limited to the above, and various design changes are possible. That is, in other embodiments, the order of the above-mentioned processes may be changed as appropriate. Also, some of the processes may be executed in parallel. The control device 160 according to the embodiment described above may be configured by a single computer, or the configuration of the control device 160 may be divided and arranged among multiple computers, and the multiple computers may cooperate with each other to function as the control device 160. In this case, some of the computers constituting the control device 160 may be mounted inside the work machine, and other computers may be provided outside the work machine.

[0065] The control device 160 according to the embodiment described above judges whether or not the operator is turning unintentionally during automatic excavation control, but is not limited to this. For example, the control device 160 according to another embodiment may have a function of executing automatic soil discharge control and judge whether or not the operator is turning unintentionally during automatic soil discharge control.

[0066] For example, the control device 160 according to another embodiment may determine whether or not an unintended rotation occurs in the manual operation of the operator. For example, the control device 160 according to another embodiment may determine whether or not the rotating body 120 is rotating when a manual operation signal of the work machine 130 is input and a manual operation signal of the rotating body 120 is not input or a neutral signal for maintaining the attitude of the rotating body 120 is input. Furthermore, the control device 160 according to another embodiment may notify the operator that an unintended rotation occurs via the operation terminal 142 or the like when it is determined that an unintended rotation occurs in the manual operation of the operator. That is, the control device 160 according to another embodiment may include an output unit that outputs a signal to the operation terminal 142 or the like to notify that a rotation occurs when the deviation between the attitude of the rotating body 120 and the reference attitude is equal to or greater than a threshold value. As a result, the control device 160 can prevent an unintended rotation from occurring by prompting the operator to input a rotation operation to the operation device 143 to cancel the unintended rotation. In other words, the output of the determination result by the control device 160 is not limited to the output of an automatic operation signal, but may be the output of a signal to a display device or the like.

[0067] The swing motor 124 of the work machine 100 according to the embodiment described above is a hydraulic motor driven by hydraulic oil, which is a working medium, but is not limited to this. For example, the swing motor 124 according to other embodiments may be an electric motor. The current flowing through the electric motor is an example of the working medium. When determining the rotation of the swing body 120 based on the measured value of the working medium as in the second embodiment, the control device 160 may specify the rotation direction based on the direction of the current flowing through the electric motor.

[0068] The work machine 100 according to the embodiment described above is a manned vehicle operated by an operator who boards and operates it, but is not limited to this. For example, the work machine 100 according to another embodiment may be a remotely operated vehicle that is operated by an operation signal acquired by communication from a remote operation device that is operated by an operator in a remote office while watching a monitor screen. In this case, some of the functions of the control device 160 may be provided in the remote operation device. [Explanation of symbols]

[0069] 100...working machine 110...traveling body 111...crawler track 112...traveling motor 120...rotating body 121...engine 122...hydraulic pump 123...control valve 124...rotation motor 130...working machine 131...boom 131C...boom cylinder 132...arm 132C...arm cylinder 133...bucket 133C...bucket cylinder 134...tilt rotator 1341...mounting section 1342...tilt section 1343...rotating section 1344...tilt encoder 1345...rotation encoder 140...operator's cab 141...operator's seat 142...operation terminal 143...operation device 143LF...left foot pedal 143LO...left operation lever 143LT...left travel lever 143RF...right foot pedal 143RO...right operation lever 143RT...Right travel lever 143SW...Start switch 151...Position and direction calculation device 152...Inclination measuring device 153...Boom stroke sensor 154...Arm stroke sensor 155...Bucket stroke sensor 156...Shape detection device 157...Pressure gauge 160...Control device 610...Processor 611...Measurement data acquisition unit 612...Operation signal input unit 613...Work machine position identification unit 614...Trajectory generation unit 615...Movement control unit 616...Turning determination unit 617...Turning control unit 618...Operation signal output unit 630...Main memory 650...Storage 670...Interface T...Target trajectory

Claims

1. A control system for a work machine including a rotating body rotatable around a rotation center and a work implement attached to the rotating body, a rotation determination unit that, when the working machine is driven, identifies a deviation between the attitude of the rotating body and a reference attitude of the rotating body; and an output unit that outputs a signal related to the determined magnitude of the deviation. Work machine control system.

2. When the magnitude of the identified deviation is greater than a predetermined threshold, the output unit outputs an operation signal for rotating the rotating body in a direction opposite to a direction in which the rotating body rotates.

2. A control system for a work machine according to claim 1.

3. The output unit outputs the signal for notifying that the rotating body is rotating when the magnitude of the identified deviation is greater than a predetermined threshold value.

2. A control system for a work machine according to claim 1.

4. The working machine includes a working tool rotatable about a second axis intersecting a first axis driven by the working machine, The turning determination unit is When the working machine is driven around the first axis without an operation for rotating the working tool around the second axis, it is determined whether the working tool is rotating around the second axis.

2. A control system for a work machine according to claim 1.

5. The rotation determination unit determines the posture of the rotating body at the start of work by driving the work machine as the reference posture. The control system of claim 1 .

6. The rotation determination unit identifies the attitude of the rotating body based on a measurement value related to a working fluid of a rotation motor that rotates the rotating body after the start of work by driving the work machine. The control system of claim 1 .

7. A control method for a work machine including a rotating body rotatable around a rotation center and a work implement attached to the rotating body, comprising: determining a deviation between an attitude of the rotating body and a reference attitude of the rotating body while the working machine is being driven; outputting a signal related to the determined magnitude of the deviation; A control method for a work machine having the above-mentioned construction.

8. A work machine control system according to any one of claims 1 to 6; A display device and an operation device are provided remotely from the work machine. Remote control system for work machines.

Citation Information

Patent Citations

  • Work machine, control device, and control method

    JP2020041354A