A control system, a control method, and a control program stored in computer-readable memory

Abstract

The processor generates a design plane defined as a plane on a vehicle body coordinate system with the representative point of the turning body as the origin. As the turning body turns, the processor rotates the design plane around the origin of the vehicle body coordinate system. The processor specifies the position of the workpiece in the vehicle body coordinate system. Based on the specified position of the workpiece and the design plane, the processor controls the workpiece.

Description

Technology Field

[0001] The present disclosure relates to a control system, a control method, and a control program.

[0002] The present application claims priority to Patent Application No. 2021-141520 filed in Japan on August 31, 2021, and incorporates the contents thereof herein by reference. Background Technology

[0003] As disclosed in Patent Document 1, a technique for controlling a working machine so that the bucket equipped in the working machine does not intrude before the design surface representing the target shape of the excavation target is known. Prior art literature

[0004] Japanese Patent Publication No. 5654144 The problem to be solved

[0005] The technology described in Patent Document 1 allows a control device to control the teeth relative to the design plane by recognizing the position of the working machine in the global coordinate system via GNSS. However, depending on the satellite's viewing environment or the configuration of the working machine, it cannot always be said that the global coordinate system can be referenced. For example, when the working machine is operating indoors, there are cases where the satellite's view is poor and GNSS cannot be referenced.

[0006] The object of the present disclosure is to provide a control system, a control method, and a control program capable of generating a design plane for controlling a work machine without referring to a global coordinate system. means of solving the problem

[0007] According to a first aspect of the present invention, a control system controls a work machine comprising a drivable vehicle body, a rotating body rotatably supported on the vehicle body, and a work tool operably supported on the rotating body. The control system comprises a processor. The processor generates a design plane defined as a plane on a vehicle body coordinate system with a representative point of the vehicle body as the origin. The processor rotates the design plane around the origin of the vehicle body coordinate system according to the rotation of the rotating body. The processor determines the position of the work tool in the vehicle body coordinate system. The processor controls the work tool based on the determined position of the work tool and the design plane.

[0008] According to a second aspect of the present invention, a control method for a work machine comprising a drivable body, a pivoting body pivotably supported on the body, and a workpiece operably supported on the pivoting body comprises a generation step, a rotational transformation step, a specification step, and a control step. The generation step generates a design plane defined as a plane on a vehicle body coordinate system with a representative point of the pivoting body as the origin. The rotational transformation step rotates the design plane around the origin of the vehicle body coordinate system according to the pivoting of the pivoting body. The specification step specifies the position of the workpiece in the vehicle body coordinate system. The control step controls the workpiece based on the specified position of the workpiece and the design plane.

[0009] According to a third aspect of the present invention, a control program is executed on a computer of a work machine comprising a drivable body, a pivoting body pivotably supported on the body, and a workpiece operably supported on the pivoting body, and executes a generation step, a rotational transformation step, a specification step, and a control step. The generation step generates a design plane defined as a plane on a vehicle body coordinate system with a representative point of the pivoting body as the origin. The rotational transformation step rotates the design plane around the origin of the vehicle body coordinate system according to the pivoting of the pivoting body. The specification step specifies the position of the workpiece in the vehicle body coordinate system. The control step controls the workpiece based on the specified position of the workpiece and the design plane. Effects of the invention

[0010] According to at least one of the above-mentioned suns, a design plane for controlling a work machine can be created without referencing a global coordinate system. Brief explanation of the drawing

[0011] [Fig. 1] This is a schematic diagram showing the configuration of a work machine related to the first embodiment. [Fig. 2] This is a drawing showing the drive system of a work machine related to the first embodiment. [Fig. 3] This is a schematic block diagram showing the configuration of a control device related to the first embodiment. [Fig. 4] This is a drawing showing an example of the resetting of the design plane according to the turning of the turning body in the first embodiment. [Fig. 5] This is a flowchart showing a method for setting a design plane related to the first embodiment. [Fig. 6] A flowchart showing the update and intervention control of the design plane according to the set turning in the first embodiment. [Fig. 7] This is a flowchart showing the update process of the design plane by the control device related to the first embodiment. [Fig. 8] This is a drawing showing the change in the design surface before and after the movement of the work machine in the first embodiment. [Fig. 9] This is a drawing showing the movement of the design plane in the first embodiment. Specific details for implementing the invention

[0012] <First Embodiment>

[0013] Components of the working machine

[0014] Hereinafter, embodiments will be described in detail with reference to the drawings.

[0015] FIG. 1 is a schematic diagram showing the configuration of a work machine (100) related to a first embodiment. The work machine (100) related to the first embodiment is, for example, a hydraulic shovel. The work machine (100) is equipped with a driving body (120), a turning body (140), a working machine (160), a driver's cab (180), and a control device (200). The work machine (100) related to the first embodiment generates a planar design surface through operation by an operator and is controlled so that the blade tip does not go beyond the design surface. At this time, since the design surface is set in a vehicle body coordinate system, construction using the design surface can be realized even in cases where positioning by GNSS, etc. is not possible, such as when the work machine (100) is constructing a tunnel.

[0016] The driving body (120) supports the working machine (100) so that it can be driven. The driving body (120) is, for example, a pair of left and right tracks.

[0017] The pivot body (140) is supported on the driving body (120) so as to be pivotable around the pivot center. The pivot body (140) is an example of the vehicle body of the working machine (100).

[0018] The work device (160) is movably supported on the slewing body (140). The work device (160) is driven by hydraulics. The work device (160) is equipped with a boom (161), an arm (162), and a bucket (163) which is a work mechanism. The base end of the boom (161) is rotatably mounted on the slewing body (140). The base end of the arm (162) is rotatably mounted on the front end of the boom (161). The base end of the bucket (163) is rotatably mounted on the front end of the arm (162). Here, the part of the slewing body (140) on which the work device (160) is mounted is called the front part. Also, with respect to the front part of the slewing body (140), the part on the opposite side is called the rear part, the part on the left is called the left part, and the part on the right is called the right part.

[0019] The driver's cab (180) is installed in the entirety of the slewing body (140). Inside the driver's cab (180), a control device (141) for an operator to operate the work machine (100) and a monitor device (142) which is a human-machine interface of the control device (200) are installed. The monitor device (142) is realized, for example, by a computer equipped with a touch panel.

[0020] The control device (200) controls the vehicle body (120), the slewing body (140), and the work device (160) based on the operation of the operating device by the operator. The control device (200) is installed, for example, inside the driver's cabin (180).

[0021] Drive system of the work machine (100)

[0022] FIG. 2 is a drawing showing the drive system of a work machine (100) related to the first embodiment.

[0023] The work machine (100) is equipped with a plurality of actuators for driving the work machine (100). Specifically, the work machine (100) is equipped with an engine (111), a hydraulic pump (112), a control valve (113), a pair of driving motors (114), a swing motor (115), a boom cylinder (116), an arm cylinder (117), and a bucket cylinder (118).

[0024] The engine (111) is a prime mover that drives the hydraulic pump (112).

[0025] The hydraulic pump (112) is driven by the engine (111) and supplies hydraulic fluid to the drive motor (114), slewing motor (115), boom cylinder (116), arm cylinder (117) and bucket cylinder (118) through the control valve (113).

[0026] The control valve (113) controls the flow rate of the hydraulic fluid supplied from the hydraulic pump (112) to the drive motor (114), slewing motor (115), boom cylinder (116), arm cylinder (117) and bucket cylinder (118).

[0027] The driving motor (114) is driven by hydraulic fluid supplied from the hydraulic pump (112) and drives the driving body (120).

[0028] The slewing motor (115) is driven by hydraulic fluid supplied from the hydraulic pump (112) and slewing the slewing body (140) relative to the driving body (120).

[0029] The boom cylinder (116) is a hydraulic cylinder for driving the boom (161). The base end of the boom cylinder (116) is mounted on the slewing body (140). The front end of the boom cylinder (116) is mounted on the boom (161).

[0030] The arm cylinder (117) is a hydraulic cylinder for driving the arm (162). The base end of the arm cylinder (117) is mounted on the boom (161). The front end of the arm cylinder (117) is mounted on the arm (162).

[0031] The bucket cylinder (118) is a hydraulic cylinder for driving the bucket (163). The base end of the bucket cylinder (118) is mounted on the arm (162). The front end of the bucket cylinder (118) is mounted on the bucket (163).

[0032] "Measuring instrument of the working machine (100)"

[0033] The work machine (100) is equipped with a plurality of sensors for measuring the posture and position of the work machine (100). Specifically, the work machine (100) is equipped with an inclination measuring instrument (101), a swing angle sensor (102), a boom angle sensor (103), a rock angle sensor (104), and a bucket angle sensor (105).

[0034] The inclination measuring device (101) measures the attitude of the turning body (140). The inclination measuring device (101) measures the inclination of the turning body (140) with respect to the horizontal plane (e.g., roll angle, pitch angle, and yaw angle). An example of the inclination measuring device (101) is an IMU (Inertial Measurement Unit). In this case, the inclination measuring device (101) measures the acceleration and angular velocity of the turning body (140) and calculates the inclination of the turning body (140) with respect to the horizontal plane based on the measurement results. The inclination measuring device (101) is installed, for example, below the driver's cab (180). The inclination measuring device (101) outputs the attitude data of the turning body (140), which is the measured value, to the control device (200).

[0035] The turning angle sensor (102) measures the turning angle of the turning body (140) relative to the driving body (120). The measured value of the turning angle sensor (102) indicates zero, for example, when the direction of the driving body (120) and the turning body (140) coincide. The turning angle sensor (102) is installed, for example, at the turning center of the turning body (140). The turning angle sensor (102) outputs the turning angle data, which is the measured value, to the control device (200).

[0036] The boom angle sensor (103) measures the boom angle, which is the rotation angle of the boom (161) relative to the swivel body (140). The boom angle sensor (103) may be an IMU mounted on the boom (161). In this case, the boom angle sensor (103) measures the boom angle based on the inclination of the boom (161) relative to the horizontal plane and the inclination of the swivel body measured by the inclination measuring instrument (101). The measured value of the boom angle sensor (103) indicates zero, for example, when the direction of a straight line passing through the base and tip of the boom (161) coincides with the front-rear direction of the swivel body (140). Additionally, the boom angle sensor (103) related to another embodiment may be a stroke sensor mounted on the boom cylinder (116). Furthermore, the boom angle sensor (103) related to another embodiment may be a rotation sensor installed on the pin connecting the swivel body (140) and the boom (161). The boom angle sensor (103) outputs boom angle data, which is a measured value, to the control device (200).

[0037] The arm angle sensor (104) measures the arm angle, which is the rotation angle of the arm (162) relative to the boom (161). The arm angle sensor (104) may be an IMU mounted on the arm (162). In this case, the arm angle sensor (104) measures the arm angle based on the inclination of the arm (162) relative to the horizontal plane and the boom angle measured by the boom angle sensor (103). The measured value of the arm angle sensor (104) indicates zero, for example, when the direction of a straight line passing through the base and tip of the arm (162) matches the direction of a straight line passing through the base and tip of the boom (161). In addition, the arm angle sensor (104) related to another embodiment may perform angle calculation by mounting a stroke sensor on the arm cylinder (117). Furthermore, the arm angle sensor (104) related to another embodiment may be a rotation sensor installed on a pin connecting the boom (161) and the arm (162). The rock angle sensor (104) outputs rock angle data, which is a measured value, to the control device (200).

[0038] The bucket angle sensor (105) measures the bucket angle, which is the rotation angle of the bucket (163) relative to the arm (162). The bucket angle sensor (105) may be a stroke sensor installed in the bucket cylinder (118) for driving the bucket (163). In this case, the bucket angle sensor (105) measures the bucket angle based on the stroke amount of the bucket cylinder. The measured value of the bucket angle sensor (105) indicates zero, for example, when the direction of a straight line passing through the base and tip of the bucket (163) matches the direction of a straight line passing through the base and tip of the arm (162). In addition, the bucket angle sensor (105) related to another embodiment may be a rotation sensor installed on a pin connecting the arm (162) and the bucket (163). Furthermore, the bucket angle sensor (105) related to another embodiment may be an IMU mounted on the bucket (163). The bucket angle sensor (105) outputs the measured value, which is bucket angle data, to the control device (200).

[0039] Configuration of the control device (200)

[0040] FIG. 3 is a schematic block diagram showing the configuration of a control device (200) related to the first embodiment.

[0041] The control unit (200) is a computer equipped with a processor (210), main memory (230), storage (250), and an interface (270). The control unit (200) is an example of a control system. The control unit (200) receives measurement values ​​from an inclination measuring instrument (101), a swing angle sensor (102), a boom angle sensor (103), a rock angle sensor (104), and a bucket angle sensor (105).

[0042] Storage (250) is a type of storage medium that is not temporary. Examples of storage (250) include magnetic disks, optical disks, magneto-optical disks, semiconductor memory, etc. Storage (250) may be an internal medium directly connected to the bus of the control device (200), or an external medium connected to the control device (200) through an interface (270) or a communication line. Storage (250) stores a control program for controlling the work machine (100).

[0043] The control program may be intended to realize a part of the function to be performed by the control device (200). For example, the control program may be intended to perform a function by combining it with another program already stored in the storage (250) or by combining it with another program installed in another device. In addition, in another embodiment, the control device (200) may be equipped with a custom LSI (Large Scale Integrated Circuit), such as a PLD (Programmable Logic Device), in addition to or instead of the above configuration. Examples of PLDs include PAL (Programmable Array Logic), GAL (Generic Array Logic), CPLD (Complex Programmable Logic Device), and FPGA (Field Programmable Gate Array). In this case, some or all of the function performed by the processor may be performed by the corresponding integrated circuit.

[0044] In the storage (250), geometric data is recorded indicating the dimensions and center of gravity positions of the slewing body (140), boom (161), arm (162), and bucket (163). Geometric data is data indicating the position of an object in a predetermined coordinate system.

[0045] Software Configuration

[0046] The processor (210) executes a control program and comprises a control amount acquisition unit (211), an input unit (212), a display control unit (213), a measurement value acquisition unit (214), a position specification unit (215), a generation unit (216), a rotation conversion unit (217), an intervention determination unit (218), an intervention control unit (219), a control signal output unit (220), and an update unit (221).

[0047] The control amount acquisition unit (211) acquires a control signal indicating the control amount of each actuator from the control device (141).

[0048] The input unit (212) receives operation input from the operator via the monitor device (142).

[0049] The display control unit (213) outputs screen data to be displayed on the monitor device (142) to the monitor device (142).

[0050] The measurement value acquisition unit (214) acquires measurement values ​​from the inclination measuring instrument (101), the turning angle sensor (102), the boom angle sensor (103), the rock angle sensor (104), and the bucket angle sensor (105).

[0051] The position determining unit (215) determines the position of the blade tip of the bucket (163) in the vehicle body coordinate system based on various measurement values ​​acquired by the measurement value acquisition unit (214) and geometric data recorded in the storage (250). The vehicle body coordinate system is an orthogonal coordinate system with the origin at the representative point of the turning body (140) (e.g., a point passing through the turning center). The calculation of the position determining unit (215) will be described later.

[0052] When the input unit (212) receives instructions to create a design surface from the operator, the generation unit (216) calculates the parameters of the design surface based on the position of the blade tip of the bucket (163) specified by the position specification unit (215). The generation unit (216) records the parameters of the design surface in the generated vehicle body coordinate system in the main memory (230).

[0053] The rotation conversion unit (217) updates the design surface parameters stored in the main memory (230) according to the rotation of the turning body (140). Specifically, the rotation conversion unit (217) rotates the design surface parameters around the origin of the vehicle body coordinate system by the amount of change in pitch angle, roll angle, and yaw angle measured by the inclination measuring instrument (101). FIG. 4 is a diagram showing an example of the resetting of the design surface according to the rotation of the turning body in the first embodiment. For example, as shown in FIG. 4, when the turning body (140) rotates after the design surface is set, the rotation conversion unit (217) calculates the amount of change in roll angle, pitch angle, and yaw angle caused by the rotation of the turning body (140) by referring to the measurement value of the inclination measuring instrument (101) acquired by the measurement value acquisition unit (214), and rotates the design surface parameters around the origin of the vehicle body coordinate system. Thus, the rotation conversion unit (217) can cancel the rotation of the design plane caused by the rotation of the rotating body (140).

[0054] The intervention determination unit (218) determines whether to limit the speed of the working machine (160) based on the positional relationship between the blade tip of a specific bucket (163) and the design surface, which is determined by the position specification unit (215). Hereinafter, the control device (200) limiting the speed of the working machine (160) is also referred to as intervention control. Specifically, the intervention determination unit (218) determines the minimum distance between the design surface and the bucket (163), and if the minimum distance is less than or equal to a predetermined distance, it determines to perform intervention control on the working machine (160).

[0055] When it is determined by the intervention judgment unit (218) that intervention control is to be performed, the intervention control unit (219) controls the amount of operation of the intervention target among the amounts of operation acquired by the amount of operation acquisition unit (211). In the intervention control, the intervention control unit (219) controls the amount of operation of the boom (161) so that the working device (160) does not intrude into the control line. As a result, the boom (161) is driven so that the speed of the bucket (163) becomes a speed corresponding to the distance between the bucket (163) and the control line. That is, when the operator operates the arm (162) to perform excavation, the intervention control unit (219) limits the speed of the cutting edge of the bucket (163) by raising the boom (161) according to the design plane.

[0056] The control signal output unit (220) outputs the amount of operation acquired by the amount of operation acquisition unit (211) or the amount of operation controlled by the intervention determination unit (218) to the control valve (113).

[0057] The update unit (221) updates the design surface parameters stored in the main memory (230) according to the operation of the work machine (100). Specifically, before and after the operation of the work machine (100), an operator operates the work machine (160) and brings the blade tip of the bucket (163) into contact with a specific location on the site. The update unit (221) moves the design surface based on the difference in the position of the blade tip of the bucket (163) in the vehicle body coordinate system before and after the operation.

[0058] Calculation of the position-specific part (215)

[0059] Here, a method for determining the position of the blade tip of the bucket (163) by the position determining unit (215) is described. The position determining unit (215) determines the position of the blade tip of the bucket (163) based on various measurement values ​​acquired by the measurement value acquisition unit (214) and geometric data recorded in the storage (250). Geometric data indicating the dimensions of the slewing body (140), boom (161), arm (162), and bucket (163) is recorded in the storage (250).

[0060] The geometric data of the swivel body (140) is the center position (x) of the joint axis supporting the boom (161) of the swivel body (140) in the local coordinate system, the vehicle body coordinate system. bm , y bm , z bm It represents ). The vehicle body coordinate system is X extending in the forward and backward directions based on the turning center of the turning body (140). sb Axis, Y extending in the left-right direction sb Z extending in the axis and vertical direction sb It is a coordinate system composed of axes. Also, the vertical direction of the pivot body (140) does not necessarily coincide with the vertical direction.

[0061] The geometric data of the boom (161) is the boom top position (x) in the boom coordinate system, which is a local coordinate system. am , y am , z am It represents ). The boom coordinate system is X extending in the longitudinal direction based on the position of the pin connecting the boom (161) and the slewing body (140). bm Axis, Y extending in the direction where the pin extends bm Axis, X bm Axis and Y bm Z perpendicular to the axis bm It is a coordinate system composed of axes. The boom top is the position of the pin connecting the boom (161) and the arm (162).

[0062] The geometric data of the arm (162) is the arm top position (x) in the local coordinate system, the arm coordinate system. bk , y bk , z bk It represents ). The arm coordinate system is X extending in the longitudinal direction based on the position of the pin connecting the arm (162) and the boom (161). am Axis, Y extending in the direction where the pin extends am Axis, X am Axis and Y am Z perpendicular to the axis am It is a coordinate system composed of axes. The arm saw is the location of the pin connecting the arm (162) and the bucket (163).

[0063] The geometric data of the bucket (163) is the position (x) of the blade tip of the bucket (163) in the local coordinate system, the bucket coordinate system. ed , y ed , z ed It represents ). The bucket coordinate system is X extending in the direction of the blade tip, based on the position of the pin connecting the bucket (163) and the arm (162). bk Axis, Y extending in the direction where the pin extends bk Axis, X bk Axis and Y bk Z perpendicular to the axis bk It is a coordinate system composed of axes.

[0064] The position specifying part (215) is the boom angle θ acquired by the measurement value acquisition part (214). bm Based on the measured values ​​and the geometric data of the slewing body (140), a boom-to-body transformation matrix T for transforming from the boom coordinate system to the body coordinate system by the following equation (1). bm sb Generates the boom-body transformation matrix T. bm sb is, Y bm Boom angle θ around the axis bm Rotate by that amount, and also the deviation between the origin of the body coordinate system and the origin of the boom coordinate system (x bm , y bm , z bm It is a matrix that moves by ). In addition, the position specification part (215) is the position of the boom top in the boom coordinate system represented by the geometric data of the boom (161) and the boom-body transformation matrix T bm sb By calculating the product of , the position of the boom top in the vehicle body coordinate system is determined.

[0065] [Number 1]

[0066]

[0067] The position specifying part (215) is the rock angle θ acquired by the measurement value acquisition part (214). amBased on the measured values ​​and the geometric data of the boom (161), an arm-boom transformation matrix T for transforming from the arm coordinate system to the boom coordinate system by the following equation (2). am bm Generates the arm-boom transform matrix T am bm silver, Y am rock angle θ around the axis am Rotate by that amount, and also the deviation between the origin of the boom coordinate system and the origin of the arm coordinate system (x am , y am , z am It is a matrix that moves by ). Also, the position specification part (215) is a boom-body transformation matrix T bm sb and the arm-boom transform matrix T am bm By calculating the product of, the arm-to-body transformation matrix T for transforming from the arm coordinate system to the body coordinate system am sb It generates. In addition, the position specification part (215) includes the position of the arm tower in the arm coordinate system represented by the geometric data of the arm (162) and the arm-body transformation matrix T. am sb By calculating the product of, the position of the arm tower in the vehicle body coordinate system is determined.

[0068] [Number 2]

[0069]

[0070] The position specifying part (215) is the bucket angle θ acquired by the measurement value acquisition part (214). bk Based on the measured values ​​and the geometric data of the arm (162), a bucket-arm transformation matrix T for transforming from the bucket coordinate system to the arm coordinate system by the following equation (3) bk am Generates the bucket-arm transform matrix T. bk am silver, Y bk Bucket angle θ around the axis bk Rotate by that amount, and also the deviation between the origin of the arm coordinate system and the origin of the bucket coordinate system (x bk , ybk , z bk It is a matrix that moves by ). Also, the position specification part (215) is the arm-body transformation matrix T am sb and bucket-arm transform matrix T bk am By calculating the product of, the bucket-to-body transformation matrix T for transforming from the bucket coordinate system to the body coordinate system. bk sb Creates.

[0071] [Number 3]

[0072]

[0073] The position specification part (215) is the position of the blade tip in the bucket coordinate system represented by the geometric data of the bucket (163) and the bucket-body transformation matrix T bk sb By calculating the product of the two, the position of the blade tip of the bucket (163) in the vehicle body coordinate system is determined.

[0074] Method of controlling the work machine (100)

[0075] Hereinafter, a control method for a work machine (100) related to the first embodiment will be described.

[0076] First, the operator of the work machine (100) operates the monitor device (142) and sets the design surface.

[0077] 《Setting of Design Aspects》

[0078] FIG. 5 is a flowchart showing a method for setting a design plane related to the first embodiment.

[0079] When the input unit (212) receives instructions to set the design plane from the monitor device (142), the display control unit (213) displays a guidance screen including a distance input field, an inclination angle input field, and a setting button on the monitor device (142) (Step S101). The guidance screen indicates that the cutting edge of the bucket (163) should be moved upward from the point where the design plane is to be set, the distance from the cutting edge to the design plane should be entered in the distance input field, the inclination angle of the design plane should be entered in the inclination angle input field, and the setting button should be operated. In the distance input field and the inclination angle input field, a distance of 0 meters, a pitch angle of 0 degrees, and a roll angle of 0 degrees are entered as initial values. Hereinafter, the distance entered in the distance input field is referred to as the input distance, and the inclination angle entered in the inclination angle input field is referred to as the input inclination angle (input pitch angle, input roll angle). The operator operates the work machine (100), moves the cutting edge of the bucket (163) to a desired position, and then operates the setting button. The input unit (212) receives input from the monitor device (142) into the distance input field and the inclination angle input field, and operation of the setting button (step S102). The input unit (212) obtains the values ​​of the distance input field and the inclination angle input field at the time the setting button is operated (step S103). The input inclination angle is an inclination angle based on the vertical direction and the front of the working machine (100) at the time of setting the design plane. That is, the input pitch angle and the input roll angle are inclinations with respect to the vertical axis of the normal of the design plane.

[0080] The measurement value acquisition unit (214) acquires the measurement values ​​of the inclination measuring instrument (101), turning angle sensor (102), boom angle sensor (103), arm angle sensor (104), and bucket angle sensor (105) at the time when the setting button is operated (step S104). The position specification unit (215) determines the position of the blade tip of the bucket (163) in the vehicle body coordinate system based on the acquired measurement values ​​(step S105).

[0081] The generation unit (216) calculates design surface parameters based on the roll angle and pitch angle (measured roll angle and measured pitch angle) obtained from the inclination measuring instrument (101) in step S104, the cutting edge position obtained in step S105, and the input distance and input inclination angle obtained in step S103. The generation unit (216) X sb Axis value 0, Y sb Axis value is 0, Z sb A vertical vector in the vehicle body coordinate system is obtained by rotating a vector with an axis value of 1 by the measured roll angle and the measured pitch angle (Step S106). The generating unit (216) obtains a position vector of the design surface by calculating the sum of the vector representing the position of the cutting edge obtained in Step S104 and the depth vector obtained by multiplying the vertical vector by the distance (Step S107). Additionally, the generating unit (216) obtains a normal vector of the design surface based on the vertical vector and the input inclination angle (Step S108). Specifically, the generating unit (216) obtains a Z that shares an origin with the vehicle body coordinate system and extends in the vertical direction. v X in the body coordinate system when the axis, measured roll angle, and measured pitch angle are zero sb X that coincides with the axis v Y in the body coordinate system when the axis, measured roll angle, and measured pitch angle are zero sb Y coinciding with the axis v A vertical coordinate system is specified as an orthogonal coordinate system composed of axes. That is, the vertical coordinate system coincides with the vehicle body coordinate system when the measured roll angle and measured pitch angle are zero. The generating unit (216) specifies the vertical coordinate system as Y v It rotates around the axis by the input pitch angle. In addition, the generating unit (216) sets the vertical coordinate system X v It rotates around the axis by the input roll angle. The generating unit (216) is Y v X of the vertical coordinate system rotated around the axis v Unit vector extending in the axial direction and X v Y of the vertical coordinate system rotated around the axis vThe normal vector of the design plane in the vertical coordinate system is obtained by taking the cross product of the unit vectors extending in the axial direction. The generating unit (216) obtains the normal vector of the design plane in the vehicle body coordinate system by rotating the normal vector in the vertical coordinate system by the measurement roll angle and the measurement pitch angle.

[0082] The generation unit (216) records the parameters of the generated design surface (normal vector and position vector) in the main memory (230) (step S109). Then, if the parameters of the design surface are already recorded in the main memory (230), the old parameters are overwritten with the new parameters.

[0083] Design Plane Update and Intervention Control Following Turning

[0084] The work machine (100) can perform work within the range reached by the work machine (160) by rotating the rotating body (140). Therefore, typically, when an operator performs work such as excavation, the work machine (100) is rotated. Since the vehicle body coordinate system is based on the rotating body (140), the positional relationship between the design plane set in the vehicle body coordinate system and the work machine (160) does not change due to the rotation of the work machine (100). Therefore, if the design plane is not updated while in the above sequence, the design plane behaves to move in accordance with the rotation of the rotating body (140) when viewed from the viewpoint of the global coordinate system. For example, if a design plane that is downward slope when viewed from the rotating body (140) is created, the slope direction of the design plane viewed from the rotating body (140) is always maintained as downward slope regardless of how the rotating body (140) is rotated.

[0085] Therefore, the control device (200) related to the first embodiment performs rotational transformation processing of the design plane to maintain the position of the design plane in the global coordinate system after the rotation of the work machine (100).

[0086] FIG. 6 is a flowchart showing the update and intervention control of a design plane according to a set turn in the first embodiment. When the operator of the work machine (100) sets the design plane by operating the monitor device (142), the control device (200) initiates the control shown below.

[0087] The operation amount acquisition unit (211) acquires operation signals of the boom (161), arm (162), bucket (163), and slewing body (140) from the operation device (141) (step S201). The measurement value acquisition unit (214) acquires measurement values ​​of the inclination measuring instrument (101), slewing angle sensor (102), boom angle sensor (103), arm angle sensor (104), and bucket angle sensor (105) (step S202).

[0088] The rotation conversion unit (217) rotates and updates the design surface stored in the main memory (230) based on the roll angle, pitch angle, and yaw angle of the rotating body (140) obtained from the inclination measuring instrument (101) in step S202 (step S203).

[0089] The position determining unit (215) calculates the position of the blade tip of the bucket (163) in the vehicle body coordinate system based on the measurement value obtained in step S202 (step S204). The intervention determination unit (218) passes through the blade tip position calculated in step S204 and the X of the vehicle body coordinate system sb -Z sb Specify a cross-section parallel to the plane (Step S205).

[0090] The intervention determination unit (218) calculates the intersection line between the cross section and the design plane generated in step S205 as a control line (step S206). The intervention determination unit (218) calculates the distance between the tip of the bucket (163) and the control line (step S207). The intervention determination unit (218) determines whether the distance between the tip of the bucket and the control line is longer than the intervention start distance (step S208). If the distance is longer than the intervention start distance (step S208: YES), the intervention control unit (219) does not perform intervention control regarding the working machine (160).

[0091] Meanwhile, if the shortest distance is less than or equal to the intervention start distance (Step S208: NO), the intervention control unit (219) calculates the target speed of the boom (161), arm (162), and bucket (163) based on the operation signals of the boom (161), arm (162), and bucket (163) obtained in Step S201 (Step S209). The intervention control unit (219) calculates the movement speed of the blade tip of the bucket (163) based on the target speed of the boom (161), arm (162), and bucket (163) and geometric data (Step S210).

[0092] The intervention control unit (219) determines the limiting speed of the blade tip of the bucket (163) based on the distance calculated in step S207 and a predetermined limiting speed table (step S211). The limiting angular speed table is a function representing the relationship between the distance between the blade tip and the control line and the limiting speed of the blade tip, wherein the limiting speed decreases as the distance decreases. The intervention control unit (219) determines whether the speed of the blade tip calculated in step S210 exceeds the limiting speed (step S212). If the speed of the blade tip exceeds the limiting speed (step S212: YES), the intervention control unit (219) calculates the speed of the boom (161) to match the speed of the blade tip to the limiting speed and sets the target speed of the boom (step S213). If the speed of the blade tip does not exceed the limiting speed (step S212: NO), the intervention control unit (219) does not perform intervention control on the working device (160).

[0093] The control signal output unit (220) generates a control signal according to the target speed of the boom (161), arm (162), and bucket (163) and the target angular velocity of the slewing body (140), and outputs it to the control valve (113) (step S214).

[0094] Update of design surface due to movement

[0095] The construction site of the work machine (100) is typically not within the range reached by the work machine (160) due to the rotation of the rotating body (140). Therefore, the operator drives the work machine (100) and performs construction at the site while moving the position of the work machine (100). Since the design plane related to the first embodiment is set in the vehicle body coordinate system, when the position of the work machine (100) moves, the design plane behaves to move in accordance with the rotating body (140) when viewed from the perspective of the global coordinate system. For example, if a pitch angle θ is set on the design plane, the height of the design plane must change by tanθ every 1 meter, so even if the work machine (100) moves 1 meter, the height of the design plane does not change.

[0096] Therefore, the control device (200) related to the first embodiment performs the design plane update process shown in FIG. 7 to maintain the position of the design plane in the global coordinate system before and after the movement of the work machine (100).

[0097] FIG. 7 is a flowchart showing the update process of a design plane by a control device related to the first embodiment.

[0098] When the operator moves the work machine (100) during construction of the design plane, the operator operates the monitor device (142) and inputs an instruction to execute an update process. When the input unit (212) of the control device (200) receives the instruction to execute an update process from the monitor device (142), the display control unit (213) displays a first guidance screen including a setting button on the monitor device (142) (Step S301). The guidance screen indicates that the cutting edge of the bucket (163) should be aligned with a target that can be contacted by the bucket (163) both before and after movement, and that the setting button should be operated. The operator operates the work machine (100), and after aligning the cutting edge of the bucket (163) with the target, operates the setting button. The input unit (212) receives the operation of the setting button from the monitor device (142) (Step S302).

[0099] The measurement value acquisition unit (214) acquires the measurement values ​​of the inclination measuring instrument (101), turning angle sensor (102), boom angle sensor (103), arm angle sensor (104), and bucket angle sensor (105) at the time when the setting button of the first guidance screen is operated (first time) (step S303). The position specification unit (215) determines the position of the blade tip of the bucket (163) in the vehicle body coordinate system based on the acquired measurement values ​​(step S304). That is, the position specification unit (215) determines the position of the target in the vehicle body coordinate system at the first time. The position specification unit (215) records the position of the blade tip in the main memory (230).

[0100] Next, the display control unit (213) displays a second guidance screen including a setting button on the monitor device (142) (step S305). The guidance screen displays instructions to drive the work machine (100) to a desired location, align the blade tip of the bucket (163) with the same target, and operate the setting button. The operator operates the work machine (100) and drives the work machine (100).

[0101] While the operator is operating the work machine (100), the measurement value acquisition unit (214) acquires the measurement values ​​of the inclination measuring instrument (101), the swing angle sensor (102), the boom angle sensor (103), the arm angle sensor (104), and the bucket angle sensor (105) (step S306). The update unit (221) determines whether the setting button has been operated (step S307). If the setting button has not been operated (step S307: NO), that is, if the movement to the desired position has not been completed, the rotation conversion unit (217) rotates and updates the design plane stored in the main memory (230) based on the measurement value of the inclination measuring instrument (101) (step S308). Then, the control device (200) returns the process to step S306 and repeats the process until the setting button is operated.

[0102] When the setting button is operated (Step S307: YES), that is, when movement to the desired position is completed, the position determining unit (215) determines the position of the blade tip of the bucket (163) in the vehicle body coordinate system based on the measurement value acquired by the measurement value acquisition unit (214) (Step S309). That is, the position determining unit (215) determines the position of the target in the vehicle body coordinate system at the time when the setting button of the second guidance screen is operated (second time).

[0103] Next, the update unit (221) calculates a translation vector which is the difference between the position vector representing the blade tip position specified in step S304 and the position vector representing the blade tip position specified in step S309 (step S310). The update unit (221) uses the calculated translation vector to move and update the design plane stored in the main memory (230) (step S311). By doing so, the update unit (221) can maintain the position of the design plane in the global coordinate system before and after driving.

[0104] Actions and Effects

[0105] Here, the update processing of the design surface by the update unit (221) is explained with reference to the drawings. FIG. 8 is a drawing showing the change in the design surface before and after the movement of the work machine (100) in the first embodiment. In the example shown in FIG. 8, the design surface has a pitch angle. At time t1, the operator aligns the blade tip of the bucket (163) with the target tgt and then drives the work machine (100) backward by a distance L. Since the design surface (s) is defined in the vehicle body coordinate system, the relative positional relationship between the turning body (140) and the design surface (s) is maintained even when the work machine (100) moves. Therefore, at the time of the global coordinate system, a misalignment occurs between the design surface (s1) before the movement of the work machine (100) and the design surface (s2) after the movement. At this time, the relative positional relationship between the tip of the bucket (163) and the swivel body (140) recorded at time t1 is also maintained, just like the design plane(s).

[0106] FIG. 9 is a diagram showing the movement of the design plane in the first embodiment. Then, at time t2, the operator aligns the blade tip of the bucket (163) with the target tgt again. The update unit (221) calculates a translation vector v indicating the amount of change in the blade tip position from the blade tip position at time t1 and the blade tip position at time t2. The translation vector v corresponds to the amount of movement of the working machine (100) as shown in FIG. 8. Therefore, the update unit (221) updates the design plane (s2) to the design plane (s3) by moving the design plane (s2) after movement according to the translation vector v. The design plane (s3) after movement becomes equivalent to the design plane (s1) before the movement of the working machine (100) at the time of the global coordinate system.

[0107] In this way, the control device (200) related to the first embodiment moves the design plane based on the difference between the position of the blade tip in the vehicle body coordinate system when the blade tip of the bucket (163) is positioned at a reference point (e.g., a target) at the first time and the position of the blade tip when the blade tip is positioned at the reference point at the second time. Thus, the control device (200) can maintain the position of the design plane in the global coordinate system even if the position of the work machine (100) changes due to driving.

[0108] Additionally, the control device (200) related to the first embodiment rotates the design plane based on the measured values ​​of the posture of the rotating body (140) during the period from the first time to the second time. Thus, the control device (200) can maintain the position of the design plane in the global coordinate system even if the posture of the work machine (100) changes due to the movement of the work machine (100). Furthermore, in another embodiment, if the work machine (100) can always maintain the same posture, the control device (200) does not need to perform rotation of the design plane. Examples of a work machine (100) that always maintains the same posture include a work machine (100) that travels on a straight rail without torsion.

[0109] <Other embodiments>

[0110] 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-described processing may be appropriately changed. In addition, some of the processing may be executed in parallel.

[0111] The control device (200) related to the above-described embodiment may be configured by a single computer, or the configuration of the control device (200) may be distributed among multiple computers and function as a control device (200) by the multiple computers cooperating with each other. In this case, some of the computers constituting the control device (200) may be mounted inside the work machine (100), and other computers may be installed outside the work machine (100).

[0112] [Industrial Applicability]

[0113] According to at least one of the above-mentioned suns, a design plane for controlling a work machine can be created without referencing a global coordinate system. Explanation of the symbols

[0114] 100: Working machine, 101: Inclination measuring instrument, 102: Slewing angle sensor, 103: Boom angle sensor, 104: Arm angle sensor, 105: Bucket angle sensor, 111: Engine, 112: Hydraulic pump, 113: Control valve, 114: Travel motor, 115: Slewing motor, 116: Boom cylinder, 117: Arm cylinder, 118: Bucket cylinder, 120: Traveling body, 140: Slewing body, 141: Operating device, 142: Monitor device, 160: Working implement, 161: Boom, 162: Arm, 163: Bucket, 180: Cab, 200: Control device, 210: Processor, 211: Manipulation amount acquisition unit, 212: Input unit, 213: Display control unit, 214: Measurement value acquisition unit, 215: Position determination unit, 216: Generation unit, 217: Rotation conversion unit, 218: Intervention determination unit, 219: Intervention control unit, 220: Control signal output unit, 221: Update unit, 230: Main memory, 250: Storage, 270: Interface

Claims

Claim 1 A control system for controlling a work machine comprising a drivable body, a rotating body rotatably supported on the drivable body, and a work machine operably supported on the rotating body, comprising a processor, wherein the processor, by operation by an operator, generates a design plane defined as a plane passing through a point specified by the operator on a vehicle body coordinate system with a representative point of the rotating body as the origin, rotates the design plane around the origin of the vehicle body coordinate system according to the rotation of the rotating body, specifies the position of the work machine in the vehicle body coordinate system, and controls the work machine based on the specified position of the work machine and the design plane. Claim 2 A control system according to claim 1, wherein the processor acquires a measurement value from an inclination measuring instrument that measures the attitude of the turning body, calculates the amount of change in attitude caused by the turning of the turning body based on the measurement value, and rotates the generated design plane based on the amount of change in attitude before and after the turning. Claim 3 A control system according to claim 1 or 2, wherein the processor moves the design plane based on the difference between a first position, which is the position of the workpiece in the vehicle body coordinate system when the workpiece is positioned at the reference point of the site at a first time, and a second position, which is the position of the workpiece in the vehicle body coordinate system when the workpiece is positioned at the reference point at a second time. Claim 4 A control system according to paragraph 3, wherein the first time is a time before driving by the driving body, and the second time is a time after driving by the driving body. Claim 5 In claim 1, the processor is a control system that generates the design plane based on the distance and angle of inclination from the workpiece supported on the turning body specified by the operator on the vehicle body coordinate system. Claim 6 A control system according to claim 1, wherein the processor generates the design plane on the vehicle body coordinate system based on the distance from the leading edge of the workpiece supported by the turning body specified by the operator by operation by the operator, and rotates the design plane while maintaining the distance from the leading edge according to the turning of the turning body. Claim 7 In claim 1, the processor is a control system that controls the workpiece based on the position of the workpiece and the design plane so that the workpiece does not go beyond the design plane. Claim 8 A control method for a work machine comprising a drivable body, a pivoting body supported pivotably on the drivable body, and a work tool supported pivotably on the pivoting body, comprising: a step of generating a design plane defined as a plane passing through a point specified by the operator on a vehicle body coordinate system with a representative point of the pivoting body as the origin by operation by an operator; a step of rotating the design plane around the origin of the vehicle body coordinate system according to the pivoting of the pivoting body; a step of specifying the position of the work tool in the vehicle body coordinate system; and a step of controlling the work tool based on the specified position of the work tool and the design plane. Claim 9 A control program stored in a computer-readable memory for a work machine having a drivable body, a pivoting body rotatably supported on the body, and a work tool operably supported on the pivoting body, wherein the computer performs the steps of: generating a design plane defined as a plane passing through a point specified by the operator on a body coordinate system with a representative point of the pivoting body as the origin, by means of operation by the operator; rotating the design plane around the origin of the body coordinate system according to the pivoting of the pivoting body; determining the position of the work tool in the body coordinate system; and controlling the work tool based on the determined position of the work tool and the design plane.

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