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

Abstract

To prevent unintended revolution from occurring during work using a work machine.SOLUTION: A work machine control system automatically actuates a revolving brake device when a work machine is driven while a revolving body is not operated.SELECTED DRAWING: Figure 1

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 having 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, a work machine attached to the rotating body, and a rotation braking device that stops the rotation of the rotating body, and includes a brake control unit that activates the rotation braking device when the rotating body is not being operated and the work machine is being driven. 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 diagram showing the configuration of a turning parking brake according to the first embodiment. [Figure 4] FIG. 2 is a schematic block diagram showing the configuration of a control device according to the first embodiment. [Diagram 5] FIG. 4 is a diagram showing an example of a target trajectory according to the first embodiment; [Figure 6] 3 is a flowchart showing an automatic excavation control method according to the first embodiment. [Figure 7] FIG. 11 is a diagram showing a configuration of a swing motor according to a second embodiment. [Figure 8] 13 is a flowchart showing an automatic excavation control method 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 swing body 120 is equipped with an engine 121 , a hydraulic pump 122 , a control valve 123 , a swing motor 124 , and a swing parking brake 125 . 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 . The swing parking brake 125 can stop the swing of the swing body 120 by a mechanical braking force. The swing parking brake 125 stops the rotation of the swing body 120 relative to the traveling body 110. The swing parking brake 125 may be, for example, a disk brake. The swing parking brake 125 is a hydraulic negative brake, and the brake is released by introducing pressure oil from a brake solenoid valve 1253. The swing parking brake 125 is an example of a swing braking device that stops the swing of 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, an operation device 143, and a turning lock switch 144 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 the excavation / dumping operation of the bucket 133 and the excavation / dumping operation of the boom 131. Specifically, when the operator of the work machine 100 tilts the right operation lever 143RO forward, the excavation operation of the boom 131 is performed. When the operator of the work machine 100 tilts the right operation lever 143RO rearward, the dumping operation of the boom 131 is performed. When the operator of the work machine 100 tilts the right operation lever 143RO to the right, the dumping operation of the bucket 133 is performed. When the operator of the work machine 100 tilts the right operation lever 143RO to the left, the excavation operation of the bucket 133 is performed. Note that in other embodiments, when the right operation lever 143RO is tilted in the forward / rearward direction, the bucket 133 may perform the dumping operation or the excavation operation, and when the right operation lever 143RO is tilted in the left / right direction, the boom 131 may perform the excavation operation or the dumping 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] The swing lock switch 144 is provided near the driver's seat 141. The swing lock switch 144 is an alternate switch that is manually operated by the operator to put the swing parking brake 125 into an activated state or a released state. When the swing lock switch 144 is in an on state, the swing parking brake 125 is in an activated state, and the swing unit 120 does not swing. The swing lock switch 144 is manually switched to an on state when it is desired to hold the swing unit 120 stopped. When the swing lock switch 144 is in an off state, the swing parking brake 125 is in a released state, and the swing unit 120 is allowed to swing.

[0024] For example, when the swing lock switch 144 is operated by the operator so that the swing parking brake 125 is in an activated state, the swing parking brake 125 is activated and the swing of the swing body 120 is stopped. When the swing parking brake 125 is activated, even if the left operation lever 143LO is operated so that the swing body 120 is rotated, the swing body 120 does not swing. For example, when operating the work machine 130 in a state in which the swing body 120 is not rotated in manual operation, the operator operates the swing lock switch 144. When the swing body 120 is not rotated, there is a high possibility that the left operation lever 143LO for rotating the swing body 120 will be in a neutral state. When the work machine 100 works on an inclined surface, for example, if the left operation lever 143LO is in a neutral state, the swing body 120 may swing due to its own weight. By operating the swing lock switch 144 to activate the swing parking brake 125, the swing body 120 is prevented from swinging even when the left operation lever 143LO is in the neutral state.

[0025] <Configuration of turning brake> FIG. 3 is a schematic diagram showing the configuration of the swing parking brake 125 according to the first embodiment. The swing parking brake 125 includes a brake cylinder 1251 , a pair of brake discs 1252 , and a brake solenoid valve 1253 . The swing lock switch 144 is disposed between the controller 160 and the brake solenoid valve 1253. The controller 160 receives one or both of an input signal indicating that the swing lock switch 144 has been operated to place the swing parking brake 125 in an applied state and an input signal indicating that the swing lock switch 144 has been operated to place the swing parking brake 125 in a released state.

[0026] The brake cylinder 1251 is a hydraulic cylinder with a spring that is driven by hydraulic oil. The brake cylinder 1251 is normally in a pushed-out state, and the rod is retracted when hydraulic oil is supplied to the rod side.

[0027] The brake disc 1252 is provided at the tip of the rod of the brake cylinder 1251. When the rod is pushed out, the brake disc 1252 comes into contact with the swing motor 124, locking the rotation of the swing motor 124. When the rod is retracted, the brake disc 1252 moves away from the swing motor 124, releasing the swing motor 124. In other words, the swing parking brake 125 is released by supplying hydraulic oil to the oil chamber on the rod side of the brake cylinder 1251. When the brake solenoid valve 1253 is driven and the brake cylinder 1251 contracts, the pair of brake discs 1252 are separated, and the swing parking brake 125 is released. When the drive of the brake solenoid valve 1253 is stopped, the brake cylinder 1251 is extended by the elastic force of the spring provided in the brake cylinder 1251. When the brake cylinder 1251 extends, the pair of brake discs 1252 come into contact with each other, and the swing parking brake 125 is activated.

[0028] The brake solenoid valve 1253 controls the operation and release of the swing parking brake 125. When the brake solenoid valve 1253 is switched to the on state, the brake solenoid valve 1253 is driven and the valve position is set to the open state, thereby releasing the swing parking brake 125. When the brake solenoid valve 1253 is excited, it releases the swing parking brake 125, and when it is de-energized, it operates the swing parking brake 125.

[0029] The brake solenoid valve 1253 is electrically connected to a control device 160, which will be described later, via a rotation lock switch 144. When the swing lock switch 144 is in the OFF state, the brake solenoid valve 1253 is always excited to release the swing parking brake 125, thereby releasing the swing lock. When the swing lock switch 144 is in the ON state, a brake actuation signal from the control device 160 is supplied to the brake solenoid valve 1253, so that the brake solenoid valve 1253 is de-energized, the swing parking brake 125 is actuated, and swing is not possible.

[0030] <<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.

[0031] 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.

[0032] 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).

[0033] 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.

[0034] 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.

[0035] Configuration of the control device 160 FIG. 4 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.

[0036] 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.

[0037] 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.

[0038] 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 turning determination unit 616, a brake control unit 617, and an operation signal output unit 618.

[0039] 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.

[0040] 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.

[0041] 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.

[0042] 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.

[0043] 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 work machine position identifying unit 613 when the excavation command signal is input and the measurement data of the shape detecting device 156. FIG. 5 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 work machine 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. 5. 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.

[0044] 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.

[0045] The rotation determination unit 616 determines whether or not an unintended rotation of the operator is occurring based on the difference between the orientation of the revolving body 120 at the start of automatic excavation control measured by the position and orientation calculator 151 and the current orientation of the revolving body 120. For example, the orientation of the revolving body 120 refers to the attitude of the revolving body.

[0046] The brake control unit 617 switches the brake release signal supplied to the brake solenoid valve 1253 between on and off. The brake release signal is a binary signal having either an on or off value. When the value of the brake release signal is off, the swing parking brake 125 is actuated, and when the value of the brake release signal is on, the swing parking brake 125 is released. The brake control unit 617 turns the value of the brake release signal off when an unintended turn by the operator occurs. The brake control unit 617 turns the value of the brake release signal on when the automatic excavation control ends.

[0047] The operation signal output unit 618 outputs the manual operation signal input to the operation signal input unit 612 and the automatic operation signal generated by the movement control unit 615. Specifically, the operation signal output unit 618 outputs the automatic operation signal generated by the movement control unit 615 and the brake 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.

[0048] 《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.

[0049] 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 613 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.

[0050] 6 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.

[0051] 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).

[0052] 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).

[0053] 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).

[0054] The turning determination unit 616 determines whether the absolute value of the calculated turning angle exceeds a predetermined turning angle threshold value (step S7). The turning angle threshold value may be set in consideration of the measurement error of the position and orientation calculator 151.

[0055] When 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. When it is determined that an unintended turn by the operator is occurring, the brake control unit 617 switches the value of the brake release signal supplied to the brake solenoid valve 1253 to OFF (step S8). After that, the brake control unit 617 maintains the value of the brake release signal to OFF until the automatic excavation control ends.

[0056] On the other hand, if the absolute value of the turning angle does not exceed the turning angle threshold value (step S7: NO), the turning determination unit 616 determines that the turning unintentional of the operator has not occurred. If it is determined that the turning unintentional of the operator has not occurred, the brake control unit 617 maintains the value of the brake release signal.

[0057] Next, 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 S9).

[0058] 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 S10). If the position of the blade tip of the bucket 133 is not located at the end point of the target trajectory T (step S10: 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 S10: YES), the brake control unit 617 sets the value of the brake release signal to ON (step S11). Then, the control device 160 ends the automatic excavation control.

[0059] 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 when it is determined that the rotating body 120 is rotating, activates the swing parking brake 125. In automatic excavation control, the work machine 100 does not output operation signals for the traveling body 110 and the rotating body 120, but drives the work implement 130. This enables the control device 160 to lock the rotation of the rotating body 120, thereby preventing the rotating body 120 from rotating unintentionally by the operator.

[0060] 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.

[0061] 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.

[0062] FIG. 7 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.

[0063] The swing determination unit 616 according to the second embodiment calculates the differential pressure between the ports of the swing motor 124 based on the difference in measurement data acquired from the two pressure gauges 157. The swing determination unit 616 determines that an unintended swing by the operator is occurring when the absolute value of the differential pressure between the ports of the swing motor 124 exceeds a predetermined differential pressure threshold. When it is determined that an unintended swing by the operator is occurring, the brake control unit 617 turns off the value of the brake release signal.

[0064] 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 rotating body 120 is rotating during automatic excavation control, and when it is determined that the rotating body 120 is rotating, activates the swing parking brake 125. In this way, the control device 160 according to the second embodiment can prevent the rotating body 120 from rotating unintentionally by the operator, as in the first embodiment.

[0065] The control device 160 according to the second 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.

[0066] Third Embodiment The work machine 100 according to the first and second embodiments activates the swing parking brake 125 when an unintended turn occurs. In contrast, the work machine 100 according to the third embodiment activates the swing parking brake 125 at the start of automatic excavation control, regardless of whether an unintended turn occurs or not. Therefore, the control device 160 according to the third embodiment does not need to be equipped with the turning determination unit 616.

[0067] Fig. 8 is a flowchart showing an automatic excavation control method according to the third embodiment. When the target trajectory T is generated, the control device 160 executes the automatic excavation control shown in Fig. 8. The target trajectory T is generated in the same manner as the control device 160 according to the first embodiment.

[0068] When the automatic excavation control starts, the brake control unit 617 switches the value of the brake release signal supplied to the brake solenoid valve 1253 to OFF (step S21). That is, the brake control unit 617 activates the swing parking brake 125 in response to the input of the excavation instruction signal, i.e., the instruction to start automatic control. Thereafter, the brake control unit 617 maintains the value of the brake release signal to OFF until the automatic excavation control ends.

[0069] The measurement data acquisition unit 611 acquires measurement data relating to the position and orientation of the revolving body 120, the relative angles of the boom 131, the arm 132, and the bucket 133, the attitude of the revolving body 120, and the surface shape of the excavation target (step S22). 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 S23). 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 S24).

[0070] The movement control unit 615 determines the target position and target posture of the boom 131 and the arm 132 based on the target position of the cutting edge and the target posture of the bucket 133 (step S25). The movement control unit 615 generates an automatic operation signal for the work implement 130 based on the identified target positions and target postures of the boom 131, the arm 132, and the bucket 133 (step S26). The operation signal output unit 618 outputs the automatic operation signal generated by the movement control unit 615 to the control valve 123 (step S27). As a result, the work implement 130 moves along the target trajectory T.

[0071] 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 S28). If the position of the blade tip of the bucket 133 is not located at the end point of the target trajectory T (step S28: NO), the control device 160 returns the process to step S22 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 S28: YES), the brake control unit 617 sets the value of the brake release signal to ON (step S29). Then, the control device 160 ends the automatic excavation control.

[0072] Actions and Effects In this way, the control device 160 according to the third embodiment activates the swing parking brake 125 in response to an excavation command signal, and executes automatic excavation control. For example, the control device 160 activates the swing parking brake 125 based on an excavation command signal, and executes automatic excavation control. This enables the control device 160 to prevent unintended turning by the work machine 100 while it is working.

[0073] 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.

[0074] The control device 160 according to the embodiment described above automatically activates the swing parking brake 125 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 removal control and automatically activate the swing parking brake 125 during automatic soil removal control.

[0075] Also, for example, the control device 160 according to another embodiment may determine whether or not 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 for the work machine 130 is input and a manual operation signal for the rotating body 120 is not input or a neutral signal for maintaining the attitude of the rotating body 120 is input. In this case, the control device 160 may release the swing parking brake 125 when a manual operation signal for the rotating body 120 is input.

[0076] 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.

[0077] 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]

[0078] 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 125...rotation parking brake 1251...brake cylinder 1252...brake disc 1253...brake solenoid valve 130...working machine 131...boom 131C...boom cylinder 132...arm 132C...arm cylinder 133...bucket 133C...bucket cylinder 134...tilt rotator 1341...mounting part 1342...tilt part 1343...rotation part 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 144...Turn lock switch 151...Position and direction calculator 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...Brake control unit 618...Operation signal output unit 630...Main memory 650...Storage 670...Interface T...Target trajectory

Claims

1. A rotating body that is rotatable around a rotation center; A work machine attached to the rotating body; A rotation braking device that stops the rotation of the rotating body; A control system for a work machine comprising: A brake control unit is provided which operates the swing braking device when the swing body is not operated and the working machine is driven. Work machine control system.

2. A rotation determination unit is provided for determining whether the rotating body is rotating when the rotating body is not operated and the work machine is driven.

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

3. The turning determination unit activates the turning braking device when it is determined that the turning body is turning.

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

4. The rotation determination unit determines whether the rotating body is rotating by comparing a posture of the rotating body at the start of work by driving the work machine with a posture of the rotating body during the work.

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

5. The rotation determination unit determines whether the rotating body is rotating 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.

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

6. receiving an instruction to start automatic control for driving the work machine without rotating the rotating body; Activating the turning braking device and executing the automatic control based on the start command.

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

7. After the automatic control is completed, the turning brake device is released. A work machine control system according to claim 6.

8. A control method for a work machine including a rotating body rotatable around a rotation center, a work implement attached to the rotating body, and a rotation braking device that stops rotation of the rotating body, comprising: A step of executing an automatic control for driving the work machine without rotating the rotating body; activating the turning brake device during execution of the automatic control; A control method for a work machine having the above-mentioned construction.

9. A work machine control system according to any one of claims 1 to 7; A display device and an operation device provided remotely from the control system of the work machine. Remote control system for work machines.

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