System, method, and program

Abstract

To provide a system that controls work machines so that they do not enter restricted areas.SOLUTION: The system identifies a virtual wall that is a surface to prohibit entry of a work machine. The system determines the travel speed of the work machine based on the virtual wall.SELECTED DRAWING: Figure 5

Description

Technical Field

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

Background Art

[0002] A technique for setting a virtual wall in space to limit the operating range of a working machine is known. The control device of the working machine can control the working machine so as not to exceed the virtual wall by limiting the amount of operation of the actuator of the working machine according to the distance between the virtual wall and the working machine.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, for a working machine equipped with a traveling device for moving the working machine, it is necessary to control the working machine so as not to exceed the virtual wall set by the working machine during traveling. An object of the present disclosure is to provide a system, a method, and a program capable of controlling a working machine so as not to enter a prohibited entry area.

Means for Solving the Problems

[0005] According to one aspect of the present disclosure, a system for controlling a working machine includes a processor. The processor identifies a virtual wall that is a surface for prohibiting entry of the working machine. The processor controls the traveling speed of the working machine based on the virtual wall.

Effects of the Invention

[0006] According to the above aspect, the system can control the construction machine so as not to enter the prohibited area.

Brief Description of Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Modes for Carrying Out the Invention

[0008] 〈First Embodiment〉 《Configuration of Construction Machine》 Hereinafter, embodiments will be described in detail with reference to the drawings. FIG. 1 is a schematic diagram showing the configuration of a construction machine 100 according to the first embodiment. The construction machine 100 according to the first embodiment is, for example, a hydraulic excavator. The construction machine 100 includes a vehicle body 110, a working machine 160, a cab 180, and a control device 200. The construction machine 100 according to the first embodiment is controlled so as not to contact the virtual wall VW based on the virtual wall VW virtually generated to define a prohibited area at the work site. Thereby, the operator can operate the construction machine 100 so as not to enter the prohibited area.

[0009] The vehicle body 110 includes a traveling body 120 and a revolving body 140. The traveling body 120 supports the working machine 100 so as to be capable of traveling. The traveling body 120 includes a pair of left and right traveling devices. The traveling body 120 includes, for example, crawler belts 121 as the traveling devices. Each of the crawler belts 121 has a traveling motor 114 which is a drive wheel. The traveling motor 114 rotates the crawler belt 121. By the traveling motor 114 rotating the crawler belt 121, the working machine 100 travels or turns. The working machine 100 can change its path in an arc shape while moving forward or backward by rotating the left and right crawler belts 121 at different speeds in the same direction. Also, the working machine 100 can perform a pivot turn about the crawler belt on the stationary side by rotating only one of the left and right crawler belts 121. Further, the working machine 100 can perform a super pivot turn about the center of the traveling body 120 by rotating the left and right crawler belts 121 at the same speed in different directions.

[0010] The slewing body 140 is supported by the traveling body 120 so as to be slewed about a slewing center. The working implement 160 is supported by the slewing body 140 so as to be operable. The working implement 160 is driven by hydraulic pressure. The working implement 160 includes a boom 161, an arm 162, and an attachment 163 which is a working tool. The attachment 163 is an example of a working tool. The attachment 163 in the example shown in FIG. 1 is a bucket. The base end portion of the boom 161 is rotatably attached to the slewing body 140. The base end portion of the arm 162 is rotatably attached to the tip end portion of the boom 161. The attachment 163 is rotatably attached to the tip end portion of the arm 162. Here, the portion of the slewing body 140 to which the working implement 160 is attached is referred to as the front portion. Also, with respect to the slewing body 140, the portion on the opposite side with reference to the front portion is referred to as the rear portion, the portion on the left side is referred to as the left portion, and the portion on the right side is referred to as the right portion.

[0011] The operator's cab 180 is provided at the front of the slewing body 140. Inside the operator's cab 180, an operating device 141 for the operator to operate the working machine 100 and a monitor device 142 which is a man-machine interface of the control device 200 are provided. The monitor device 142 is realized by, for example, a computer equipped with a touch panel.

[0012] The control device 200 controls the traveling body 120, the slewing body 140, and the working machine 160 based on the operation of the operating device 141 by the operator. The control device 200 is provided, for example, inside the operator's cab 180.

[0013] 《Drive system of the working machine 100》 FIG. 2 is a diagram showing the drive system of the working machine 100 according to the first embodiment. The working machine 100 includes a plurality of actuators for driving the working machine 100. Specifically, the working machine 100 includes a power source 111, a hydraulic pump 112, a control valve 113, a pair of traveling motors 114, a slewing motor 115, a boom cylinder 116, an arm cylinder 117, and an attachment cylinder 118.

[0014] The power source 111 drives the hydraulic pump 112. The power source 111 is, for example, an engine. The hydraulic pump 112 is driven by the power source 111 and supplies hydraulic oil to the traveling motor 114, the slewing motor 115, the boom cylinder 116, the arm cylinder 117, and the attachment cylinder 118 via the control valve 113. The control valve 113 controls the flow rate of the hydraulic oil supplied from the hydraulic pump 112 to the traveling motor 114, the slewing motor 115, the boom cylinder 116, the arm cylinder 117, and the attachment cylinder 118. The traveling motor 114 is driven by the hydraulic oil supplied from the hydraulic pump 112 to rotate the crawler belt 121. The slewing motor 115 is driven by the hydraulic oil supplied from the hydraulic pump 112 to slewing the slewing body 140 with respect to the traveling body 120.

[0015] The boom cylinder 116 is a hydraulic cylinder for driving the boom 161. The base end portion of the boom cylinder 116 is attached to the revolving body 140. The tip end portion of the boom cylinder 116 is attached to the boom 161. The arm cylinder 117 is a hydraulic cylinder for driving the arm 162. The base end portion of the arm cylinder 117 is attached to the boom 161. The tip end portion of the arm cylinder 117 is attached to the arm 162. The attachment cylinder 118 is a hydraulic cylinder for driving the attachment 163. The base end portion of the attachment cylinder 118 is attached to the arm 162. The tip end portion of the attachment cylinder 118 is attached to the attachment 163.

[0016] "Measurement System of the Working Machine 100" The working machine 100 is provided with a plurality of sensors for measuring the posture and position of the working machine 100. Specifically, the working machine 100 is provided with an inclinometer 101, a position and azimuth detector 106, a slewing angle sensor 102, a boom angle sensor 103, an arm angle sensor 104, and an attachment angle sensor 105.

[0017] The inclinometer 101 measures the posture of the revolving body 140. The inclinometer 101 measures the inclination of the revolving body 140 with respect to the horizontal plane (for example, roll angle, pitch angle, and yaw angle). As an example of the inclinometer 101, an IMU (Inertial Measurement Unit) can be mentioned. In this case, the inclinometer 101 measures the acceleration and angular velocity of the revolving body 140, and calculates the inclination of the revolving body 140 with respect to the horizontal plane based on the measurement results. The inclinometer 101 is installed, for example, below the operator's cab 180. The inclinometer 101 outputs the posture data of the revolving body 140, which is a measured value, to the control device 200.

[0018] The turning angle sensor 102 measures the turning angle of the swivel body 140 with respect to the traveling body 120. The measured value of the turning angle sensor 102 indicates zero, for example, when the directions of the traveling body 120 and the swivel body 140 coincide. The turning angle sensor 102 is installed, for example, at the center of rotation of the swivel body 140. The turning angle sensor 102 outputs the turning angle data, which is the measured value, to the control device 200.

[0019] The boom angle sensor 103 measures the boom angle, which is the rotation angle of the boom 161 with respect to the swivel body 140. The boom angle sensor 103 may be an IMU attached to the boom 161. In this case, the boom angle sensor 103 measures the boom angle based on the inclination of the boom 161 with respect to the horizontal plane and the inclination of the swivel body measured by the inclinometer 101. The measured value of the boom angle sensor 103 indicates zero, for example, when the direction of the straight line passing through the base end and the tip of the boom 161 coincides with the front-rear direction of the swivel body 140. Note that the boom angle sensor 103 according to another embodiment may be a stroke sensor attached to the boom cylinder 116. Further, the boom angle sensor 103 according to another embodiment may be a rotation sensor provided on the boom pin connecting the swivel body 140 and the boom 161. The boom angle sensor 103 outputs the boom angle data, which is the measured value, to the control device 200.

[0020] The arm angle sensor 104 measures the arm angle, which is the rotation angle of the arm 162 with respect to the boom 161. The arm angle sensor 104 may be an IMU attached to the arm 162. In this case, the arm angle sensor 104 measures the arm angle based on the inclination of the arm 162 with respect 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 the straight line passing through the proximal end and the distal end of the arm 162 coincides with the direction of the straight line passing through the proximal end and the distal end of the boom 161. Note that, for the arm angle sensor 104 according to other embodiments, a stroke sensor may be attached to the arm cylinder 117 to calculate the angle. Further, for the arm angle sensor 104 according to other embodiments, it may be a rotation sensor provided on the arm pin connecting the boom 161 and the arm 162. The arm angle sensor 104 outputs the arm angle data, which is the measured value, to the control device 200.

[0021] The attachment angle sensor 105 measures the attachment angle, which is the rotation angle of the attachment 163 with respect to the arm 162. The attachment angle sensor 105 may be a stroke sensor provided on the attachment cylinder 118 for driving the attachment 163. In this case, the attachment angle sensor 105 measures the attachment angle based on the stroke amount of the attachment cylinder 118. The measured value of the attachment angle sensor 105 indicates zero, for example, when the direction of the straight line passing through the proximal end and the tip of the attachment 163 coincides with the direction of the straight line passing through the proximal end and the tip of the arm 162. Note that, for the attachment angle sensor 105 according to other embodiments, it may be a rotation sensor provided on the bucket pin connecting the arm 162 and the attachment 163. Further, for the attachment angle sensor 105 according to other embodiments, it may be an IMU attached to the attachment 163. The attachment angle sensor 105 outputs the attachment angle data, which is the measured value, to the control device 200.

[0022] The position and orientation detector 106 detects the position and orientation of the working machine 100. The position and orientation detector 106 includes two receivers that receive positioning signals from artificial satellites constituting the GNSS (Global Navigation Satellite System). An example of GNSS is GPS (Global Positioning System). The two receivers are installed at different positions of the working machine 100, respectively. The position and orientation detector 106 detects the position of the representative point of the slewing body 140 in the field coordinate system based on the positioning signals received by the receivers. The position and orientation detector 106 calculates the orientation of the slewing body 140 as the relationship between the installation positions of the two receivers with respect to the installation position of one of the receivers using the positioning signals received by the two receivers.

[0023] 《Configuration of the control device 200》 FIG. 3 is a schematic block diagram showing the configuration of the control device 200 according to the first embodiment. The control device 200 is a computer including a processor 210, a main memory 230, a storage 250, and an interface 270. The control device 200 is an example of a control system. The control device 200 receives measurement values from the inclinometer 101, the slewing angle sensor 102, the boom angle sensor 103, the arm angle sensor 104, the attachment angle sensor 105, and the position and orientation detector 106.

[0024] The storage 250 is a non-transitory tangible storage medium. Examples of the storage 250 include a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, and the like. The storage 250 may be an internal medium directly connected to the bus of the control device 200, or may be an external medium connected to the control device 200 via the interface 270 or a communication line. The storage 250 stores a control program for controlling the working machine 100.

[0025] The control program may be for realizing a part of the functions to be exerted by the control device 200. For example, the control program may exert functions by combination with other programs already stored in the storage 250, or by combination with other programs implemented in other devices. In other embodiments, the control device 200 may include 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 functions realized by the processor may be realized by the integrated circuit.

[0026] The storage 250 records geometry data representing the dimensions and center-of-gravity positions of the traveling body 120, the revolving body 140, the boom 161, the arm 162, and the attachment 163. The geometry data is data representing the positions of objects in a predetermined coordinate system.

[0027] The storage 250 records parameter data for each virtual wall VW. The virtual wall VW according to the first embodiment is provided vertically with respect to the ground surface. The parameters of the virtual wall VW may be the positions (latitude and longitude) of two points in the site coordinate system. In this case, the plane formed between the edges extending vertically from the two specified points is specified as the virtual wall VW. Note that in other embodiments, the present invention is not limited to this, and the parameters of the virtual wall VW may be represented by the three dimensions of one point in the site coordinate system and the azimuth in which the wall surface faces.

[0028] In the storage 250, a travel speed table, which is a function showing the relationship between the distance to the virtual wall VW and the speed limit, is recorded. The speed limit is the speed at which the work machine 100 can stop without exceeding the virtual wall VW when traveling at that speed. The travel speed table is a function in which the speed limit decreases as the distance to the virtual wall VW decreases.

[0029] 《Software Configuration》 By executing a control program, the processor 210 includes an operation signal receiving unit 211, an input unit 212, a display control unit 213, a measured value receiving unit 214, a position specifying unit 215, an intervention determination unit 218, an intervention control unit 219, and a control signal output unit 220.

[0030] The operation signal receiving unit 211 receives an operation signal indicating the operation direction and operation amount of each actuator from the operation device 141. The display control unit 213 outputs screen data to be displayed on the monitor device 142 to the monitor device 142. The measured value receiving unit 214 receives measured values from the inclinometer 101, the turning angle sensor 102, the boom angle sensor 103, the arm angle sensor 104, the attachment angle sensor 105, and the position and orientation detector 106.

[0031] The position specifying unit 215 specifies the position of the outer shell of the working machine 100 in the vehicle body coordinate system. The outer shell of the working machine 100 is the outer shape of the working machine 100. The outer shell of the working machine 100 is defined, for example, by the shape forming the outer shapes of the revolving body 140 and the working device 160. Specifically, the position specifying unit 215 specifies the positions of a plurality of points (control points) of the outer shell of the working machine 100 in the vehicle body coordinate system based on the various measurement values received by the measurement value receiving unit 214 and the geometry data recorded in the storage 250. The control points specified by the position specifying unit 215 include the tip of the attachment 163 (for example, the cutting edge of the bucket), the end on the attachment 163 side of the arm 162 (arm top), the end on the boom 161 side of the arm 162 (arm bottom), the point behind the counterweight of the revolving body 140, and the ends of the crawlers 121. The vehicle body coordinate system is a rectangular coordinate system with the representative point of the revolving body 140 (for example, the point passing through the center of rotation) as the origin. The calculation of the position specifying unit 215 will be described later. Note that the points specified by the position specifying unit 215 are not limited to these. In the first embodiment, the shapes of the outer shells of the attachment 163, the arm top, and the arm bottom are simulated by the virtual sphere VS. The virtual sphere VS is a virtual sphere that encloses the outer shell of the target portion whose shape changes according to the angle formed by two objects like the joint portion of the working device 160. By regarding the surface of the virtual sphere VS as the outer shell of the target portion, the control device 200 can determine the possibility of contact between the virtual wall VW and the outer shell while reducing the amount of calculation.

[0032] The intervention determination unit 218 determines whether to limit the speed of the traveling body 120 based on the positional relationship between the control points specified by the position specifying unit 215 and the virtual wall VW. Hereinafter, the control device 200 limiting the speed of the traveling body 120 is also referred to as intervention control. Specifically, the intervention determination unit 218 obtains the minimum distance between the virtual wall VW and the working machine 100, and determines that intervention control is to be performed on the traveling body 120 when the minimum distance is equal to or less than a predetermined distance. Note that the control device 200 according to another embodiment may perform intervention control related to the revolving body 140 and the working device 160 in addition to the intervention control related to the traveling body 120.

[0033] When it is determined by the intervention determination unit 218 that intervention control is to be performed, the intervention control unit 219 controls the operation amount of the actuator to be intervened among the operation signals received by the operation signal receiving unit 211. The control signal output unit 220 outputs the operation signal received by the operation signal receiving unit 211 or the operation signal controlled by the intervention determination unit 218 to the control valve 113.

[0034] 《Calculation of the position specifying unit 215》 Here, a method for specifying the position of a point on the outer shell of the working machine 100 by the position specifying unit 215 will be described. The position specifying unit 215 specifies the position of a point on the outer shell based on various measurement values received by the measurement value receiving unit 214 and the geometry data recorded in the storage 250. The storage 250 records geometry data representing the dimensions of the slewing body 140, the boom 161, the arm 162, and the attachment 163.

[0035] The geometry data of the traveling body 120 is the position (x tb , y tb , z tb ) of a point on the outer shell of the traveling body 120 in the traveling body coordinate system, which is a local coordinate system. As points on the outer shell of the traveling body 120, for example, the outer points of the front end and the rear end of the crawler 121 can be mentioned. The traveling body coordinate system is an X tb axis extending in the front-rear direction, a Y tb axis extending in the left-right direction, and a Z tb axis extending in the up-down direction, and is composed of a coordinate system. Note that the up-down direction of the slewing body 140 does not necessarily coincide with the vertical direction.

[0036] The geometry data of the slewing body 140 is the position (x bm , y bm , z bm ) of the boom pin that supports the boom 161 of the slewing body 140 in the vehicle body coordinate system, which is a local coordinate system, and the position (x sp , y sp , z sp) is shown. As points on the outer shell of the revolving body 140, for example, points that are likely to come into contact with the wall surface during turning, such as the protruding points of the counterweight, can be mentioned. The vehicle body coordinate system extends in the front-rear direction with reference to the center of rotation of the revolving body 140 as the X sb axis, the Y sb axis that extends in the left-right direction, and the Z sb axis that extends in the up-down direction. It should be noted that the up-down direction of the revolving body 140 does not necessarily coincide with the vertical direction.

[0037] The geometric data of the boom 161 indicates the position (x am , y am , z am ) of the arm pin in the boom coordinate system, which is a local coordinate system. The boom coordinate system extends in the longitudinal direction as the X bm axis with reference to the position of the pin connecting the boom 161 and the revolving body 140, the Y bm axis that extends in the direction in which the pin extends, and the Z bm axis that is orthogonal to the X bm axis and the Y bm axis.

[0038] The geometric data of the arm 162 indicates the position (x at , y at , z at ) of the bucket pin in the arm coordinate system, which is a local coordinate system. The arm coordinate system extends in the longitudinal direction as the X am axis with reference to the position of the pin connecting the arm 162 and the boom 161, the Y am axis that extends in the direction in which the pin extends, and the Z am axis that is orthogonal to the X am axis and the Y am axis. Also, the geometric data of the arm 162 includes information on the center points and radii of the virtual spheres VS1 and VS2 that simulate the outer shells of the arm bottom and the arm top. The virtual sphere VS1 representing the arm bottom has the arm pin as the center and encloses at least the base end of the arm 162. The virtual sphere VS2 representing the arm top has the bucket pin as the center and encloses at least the tip of the arm 162. The arm bottom and the arm top are one of the points on the outer shell of the working machine 100.

[0039] The geometric data of attachment 163 has information on the center point and radius of a virtual sphere VS3 that simulates the outer shell of attachment 163. The virtual sphere VS3 representing attachment 163 encloses the entire attachment 163. The center point of virtual sphere VS3 may be the midpoint of the line segment connecting the midpoint of the rotation axis of attachment 163 and the midpoint of the tip of attachment 163. Also, in other embodiments, the center point of virtual sphere VS3 may be the geometric center of attachment 163, or may be a point such that the virtual sphere VS enclosing attachment 163 becomes the minimum enclosing sphere. The geometric data of attachment 163 indicates the position (x cp , y cp , z cp ) of the center point of virtual sphere VS3 in the attachment coordinate system, which is a local coordinate system. The attachment coordinate system is based on the position of the pin connecting attachment 163 and arm 162, and includes an X at -axis extending in the direction of the tip, a Y at -axis extending in the direction in which the pin extends, and a Z at -axis orthogonal to the X at -axis and the Y at -axis.

[0040] Based on the measured value of the turning angle θ sb received by the measurement value receiving unit 214 and the geometric data of the traveling body 120, the position specifying unit 215 generates a traveling body-vehicle body conversion matrix T tb sb for converting from the traveling body coordinate system to the vehicle body coordinate system according to the following formula (1). The traveling body-vehicle body conversion matrix T tb sb is a matrix that rotates in the opposite direction by the turning angle θ tb about the Z sb -axis. Also, the position specifying unit 215 obtains the position of the outer shell of the traveling body 120 in the vehicle body coordinate system by obtaining the product of the position of the outer shell of the traveling body 120 in the traveling body coordinate system indicated by the geometric data of the traveling body 120 and the traveling body-vehicle body conversion matrix T tb sb .

[0041]

number

[0042] The position identification unit 215 detects the boom angle θ bm Based on the measured values ​​and the geometry data of the rotating body 140, a boom-body transformation matrix T for transforming from the boom coordinate system to the body coordinate system is calculated by the following formula (2). bm sb Generate the boom-body transformation matrix T bm sb is Y bm Boom angle θ around the axis bm and the deviation between the origin of the vehicle coordinate system and the origin of the boom coordinate system (x bm , y bm , z bm ) is the matrix that translates the In addition, the position identification unit 215 identifies the position of the arm pin in the boom coordinate system indicated by the geometry data of the boom 161 and the boom-vehicle body transformation matrix T bm sb The position of the arm pin in the vehicle body coordinate system is calculated by multiplying this by

[0043]

number

[0044] The position specifying unit 215 detects the arm angle θ am Based on the measured values ​​and the geometry data of the boom 161, an arm-boom transformation matrix T for transforming from the arm coordinate system to the boom coordinate system is calculated by the following formula (3). am bm The arm-boom transformation matrix T am bm is Y am Arm angle θ around the axis am and the deviation between the origin of the boom coordinate system and the origin of the arm coordinate system (x am , y am , z amis a matrix for only translational movement. Further, the position specifying unit 215 is the boom-body transformation matrix T bm sb and the arm-boom transformation matrix T am bm to obtain the arm-body transformation matrix T am sb for transformation from the arm coordinate system to the body coordinate system. Further, the position specifying unit 215 calculates the product of the position of the bucket pin in the arm coordinate system indicated by the geometry data of the arm 162 and the arm-body transformation matrix T am sb to obtain the position of the bucket pin in the body coordinate system.

[0045]

Number

[0046] Based on the measured value of the attachment angle θ at received by the measurement value receiving unit 214 and the geometry data of the arm 162, the position specifying unit 215 generates the attachment-arm transformation matrix T at am for transformation from the attachment coordinate system to the arm coordinate system according to the following formula (4). The attachment-arm transformation matrix T at am is a matrix that rotates by the attachment angle θ at around the Y at axis and translates by the deviation (x at , y at , z at ) between the origin of the arm coordinate system and the origin of the attachment coordinate system. Further, the position specifying unit 215 calculates the product of the arm-body transformation matrix T am sb and the attachment-arm transformation matrix T at am to generate the attachment-body transformation matrix T at sb for transformation from the attachment coordinate system to the body coordinate system.

[0047]

Number

[0048] The position specifying unit 215 obtains the position of the tip end in the attachment coordinate system indicated by the geometry data of the attachment 163 and the product with the attachment-body transformation matrix T at sb to obtain the position of the center point of the virtual sphere VS3 of the attachment 163 in the vehicle body coordinate system.

[0049] 《Control Method of the Working Machine 100》 Hereinafter, the control method of the working machine 100 according to the first embodiment will be described. When starting up, the control device 200 reads out the parameters of the virtual wall VW, the geometry data, the limit angular velocity table, and the limit speed table recorded in the storage 250 into the main memory 230.

[0050] FIG. 4 is a flowchart showing the intervention control by the control device 200 according to the first embodiment. The control device 200 starts the following control.

[0051] The operation signal receiving unit 211 receives an operation signal for the pair of left and right traveling devices of the traveling body 120 from the operation device 141 (step S1). The measurement value receiving unit 214 receives the measurement values of the inclination measuring device 101, the turning angle sensor 102, the boom angle sensor 103, the arm angle sensor 104, the attachment angle sensor 105, and the position and orientation detector 106 (step S2).

[0052] The intervention control unit 219 determines the position and orientation of the revolving body 140 based on the measurement values received in step S2. The intervention control unit 219 specifies the position of the virtual wall VW in the vehicle body coordinate system based on the parameters of the virtual wall VW and the position and orientation of the revolving body 140 (step S3). The position specifying unit 215 specifies the control point of the working machine 100 and the position of the virtual sphere VS in the vehicle body coordinate system based on the measurement values received in step S2 (step S4).

[0053] The intervention determination unit 218 selects each of the virtual walls VW identified in step S3 one by one (step S5), and executes the processes from step S6 to step S15 below. The intervention determination unit 218 calculates the distances between the virtual wall VW selected in step S5 and the control point and the virtual sphere VS identified in step S4, respectively (step S6). FIG. 5 is a diagram showing how to obtain the distances between the control point and the virtual sphere VS and the virtual wall VW by the control device 200 according to the first embodiment. The intervention determination unit 218 obtains the length of a line segment parallel to the direction in which the traveling body 120 faces when connecting the control point or the virtual sphere VS of the work machine 100 and the virtual wall VW as the distance between the control point or the virtual sphere VS and the virtual wall VW. Note that when the wall surface of the virtual wall VW and the direction in which the traveling body 120 faces are parallel, the distance cannot be obtained. In this case, the intervention determination unit 218 may set the distance between the control point or the virtual sphere VS and the virtual wall VW as a distance at which the speed is not restricted in the speed limit table.

[0054] The intervention determination unit 218 determines whether the operation on the traveling body 120 is a straight-ahead operation, a turning operation, or a stop operation based on the operation signal received in step S1 (step S7). The intervention determination unit 218 determines that the operation on the traveling body 120 is a straight-ahead operation when the operation directions of the right crawler belt 121 and the left crawler belt 121 match and the difference in the operation amounts of the right crawler belt 121 and the left crawler belt 121 is equal to or less than a predetermined threshold. The intervention determination unit 218 determines that the operation on the traveling body 120 is a turning operation when the operation directions of the right crawler belt 121 and the left crawler belt 121 do not match, or when the difference in the operation amounts of the right crawler belt 121 and the left crawler belt 121 exceeds the predetermined threshold. The intervention determination unit 218 determines that the operation on the traveling body 120 is a stop operation when the operation amounts of both the right crawler belt 121 and the left crawler belt 121 are below the predetermined threshold.

[0055] When it is determined that the operation on the traveling body 120 is a straight-ahead operation (step S7: straight-ahead), the intervention determination unit 218 determines whether the traveling direction of the traveling body 120 is a direction approaching or departing from the virtual wall VW selected in step S5 (step S8). When it is determined that the traveling body 120 is in a direction approaching the virtual wall (step S8: approaching), the intervention determination unit 218 determines to set all the control points and the virtual sphere VS specified in step S4 as interference determination targets (step S9).

[0056] When the operation on the traveling body 120 is a straight-ahead operation and it is determined that the traveling body 120 is in a direction departing from the virtual wall (step S8: departing), or when it is determined that the operation on the traveling body 120 is a stop operation (step S7: stop), the intervention determination unit 218 determines not to set all the control points and the virtual sphere VS specified in step S4 as interference determination targets (step S10). In this case, the intervention determination unit 218 replaces the distances related to the control points and the virtual sphere VS that are not interference determination targets obtained in step S6 with distances at which the speed is not restricted in the speed limit table.

[0057] When it is determined that the operation on the traveling body 120 is a turning operation (step S7: turning), the intervention determination unit 218 specifies the turning direction of the traveling body 120 based on the operation signal received in step S1 (step S11).

[0058] Based on the turning direction of the traveling body 120 specified in step S11, the intervention determination unit 218 specifies the control points and the virtual sphere VS that approach the virtual wall among the control points and the virtual sphere VS specified in step S4 (step S12). FIG. 6 is a diagram showing a method for specifying interference determination targets when the traveling body 120 of the working machine 100 according to the first embodiment turns. The intervention determination unit 218 is the X of the vehicle body coordinate system and the virtual wall VW selected in step S5 sb -Y sbA determination plane that is orthogonal to the plane and passes through the midpoint M of the pair of left and right crawlers 121 is set. The midpoint M is the intersection point of a line connecting the right front end of the right crawler 121 and the left rear end of the left crawler 121 and a line connecting the right rear end of the right crawler 121 and the left front end of the left crawler 121 when the traveling body 120 is viewed from the vertical direction. Note that the midpoint M may be a point passing through the turning center of the revolving body 140.

[0059] As shown in FIG. 6, for example, when it is determined in step S11 that the turning direction of the traveling body 120 is the left direction, the intervention determination unit 218 determines to target for interference determination a point existing on the right side of the determination plane and a virtual sphere VS having a center point on the right side of the determination plane toward the virtual wall VW. Further, for example, when it is determined in step S11 that the turning direction of the traveling body 120 is the right direction, the intervention determination unit 218 determines to target for interference determination a point existing on the left side of the determination plane and a virtual sphere VS having a center point on the left side of the determination plane toward the virtual wall VW. That is, the intervention determination unit 218 targets for interference determination the control point and the virtual sphere VS on the side that rotates in the direction approaching the virtual wall VW due to the turning of the traveling body 120 among the control points and the virtual sphere VS specified in step S4. On the other hand, the intervention determination unit 218 does not target for interference determination the control point and the virtual sphere VS on the side that rotates in the direction away from the virtual wall VW due to the turning of the traveling body 120 among the control points and the virtual sphere VS specified in step S4. Note that the intervention determination unit 218 may replace, in the restricted speed table, the distance related to the control point and the virtual sphere VS that are not targeted for interference determination among the distances between the virtual wall VW calculated in step S6 and the control point and the virtual sphere VS with a distance at which the speed is not restricted.

[0060] When a control point and a virtual sphere VS to be subjected to interference determination are determined in any one of steps S9 to S12, the intervention determination unit 218 identifies the control point or the virtual sphere VS having the shortest distance from the virtual wall VW selected in step S5 among the control points to be subjected to interference determination (step S13). The intervention control unit 219 determines an allowable speed based on the distance related to the control point or the virtual sphere VS identified in step S13 from a limit speed table (step S14). The intervention control unit 219 determines a deceleration rate of the crawler belt 121 based on the command speed for each of the pair of left and right crawler belts 121 indicated by the operation signal received in step S1 and the allowable speed determined in step S14 (step S15). Specifically, the intervention control unit 219 calculates the deceleration rate by dividing the allowable speed by the speed of the pair of left and right crawler belts 121 indicated by the operation amount that approaches the virtual wall VW at a higher speed.

[0061] When the control device 200 performs the calculations from step S6 to step S15 for each virtual wall VW and calculates the deceleration rate for each virtual wall VW, the intervention control unit 219 identifies the smallest one among the calculated deceleration rates (step S16). The intervention control unit 219 calculates a target speed for each of the pair of left and right crawler belts 121 by multiplying the command speed for each of the pair of left and right crawler belts 121 indicated by the operation signal by the deceleration rate identified in step S16 (step S17). As a result, the ratio of the traveling speed indicated by the operation signal for the right crawler belt 121 to the target speed for the right crawler belt 121 and the ratio of the traveling speed indicated by the operation signal for the left crawler belt 121 to the target speed for the right crawler belt 121 become equal. Therefore, the control device 200 can rotate the pair of left and right crawler belts 121 at the same ratio as the ratio of the operation amounts indicated by the operation signals for the pair of left and right crawler belts 121.

[0062] The control signal output unit 220 generates a control signal based on the target speed calculated in step S17 and outputs it to the control valve 113 (step S18).

[0063] 《Function and Effect》 In this way, the control device 200 according to the first embodiment controls the working machine 100 according to the following procedure. The control device 200 identifies a virtual wall VW that is virtually generated to define a prohibited entry area of the working machine 100. The control device 200 controls the traveling speed so that the virtual wall VW and the working machine 100 do not come into contact with each other. Thereby, it is possible to control the working machine 100 so as not to enter the prohibited entry area.

[0064] Further, when both of the pair of left and right crawlers 121 are operated in a direction approaching the virtual wall VW, the control device 200 according to the first embodiment restricts the traveling speed so that the virtual wall VW and the working machine 100 do not come into contact with each other. When both of the pair of left and right crawlers 121 are operated in a direction away from the virtual wall VW, the traveling speed is not restricted. Thereby, when the working machine 100 and the virtual wall VW are close to each other, when an operation of approaching the virtual wall VW is performed, the traveling speed is restricted, and when an operation of moving away from the virtual wall VW is performed, the working machine 100 can quickly move away from the virtual wall VW.

[0065] Further, when the operation directions of the pair of left and right crawlers 121 are different from each other, or when the operation amounts of the pair of left and right crawlers 121 are different from each other, the control device 200 according to the first embodiment identifies a portion of the outer shell of the working machine 100 that approaches the virtual wall VW, and determines the traveling speed based on the distance between the identified portion and the virtual wall VW. When the operation directions of the pair of left and right crawlers 121 are different from each other, or when the operation amounts of the pair of left and right crawlers 121 are different from each other, the working machine 100 turns. At this time, a portion of the working machine 100 that exists on the side opposite to the turning direction does not come into contact with the virtual wall VW due to the turning. Therefore, according to the control device according to the first embodiment, the turning speed of the traveling body 120 can be appropriately controlled.

[0066] <Other Embodiments> Although one embodiment has been described in detail with reference to the drawings above, the specific configuration is not limited to the above, and various design changes and the like are possible. That is, in other embodiments, the order of the above-described processes may be appropriately changed. Also, some processes may be executed in parallel. The control device 200 according to the above-described embodiment may be configured by a single computer, or the configuration of the control device 200 may be divided and arranged among a plurality of computers, and the plurality of computers may function as the control device 200 by cooperating with each other. At this time, some of the computers constituting the control device 200 may be mounted inside the working machine 100, and other computers may be provided outside the working machine 100.

[0067] The working machine 100 according to the above-described embodiment includes the crawler 121 as a traveling device, but is not limited thereto. For example, in other embodiments, the working machine 100 may include wheels as a traveling device. Further, the wheels may be steerable wheels that can be steered by a steering mechanism. When the working machine 100 includes steerable wheels, the control device 200 can determine a turning operation based on the steering angle.

[0068] The control device 200 according to the above-described embodiment specifies the operation of the traveling body 120 based on an operation signal, but is not limited thereto. For example, the control device according to other embodiments may specify the operation of the traveling body 120 from the measured value of the rotational speed of the crawler 121.

[0069] The virtual wall VW according to the above-described embodiment is recorded in advance in the storage 250 of the control device 200, but is not limited thereto. For example, the virtual wall VW according to other embodiments may be calculated based on the position of another working machine 100 so as not to interfere with the other working machine 100. Further, the virtual wall VW according to the above-described embodiment is represented in the field coordinate system, but the virtual wall VW according to other embodiments may be represented in the vehicle body coordinate system.

[0070] The work machine 100 according to the above-described embodiment is operated by an operator boarding the cab 180, but the work machine 100 according to other embodiments is not limited thereto. FIG. 7 is a diagram showing the configuration of a work system according to another embodiment. The work machine 100 according to another embodiment may be operated by a remote control device 500 as shown in FIG. 7. The work machine 100 to be remotely operated further includes an imaging device 119 in addition to the configuration of the above-described embodiment, and the control device 200 transmits the image captured by the imaging device 119 to the remote control device 500 in real time. The remote control device 500 includes a driver's seat 510, a display 520, an operating device 530, and a remote control server 540. The remote control server 540 causes the display 520 to display the image received from the work machine 100. Thereby, the operator can recognize the situation around the remote work machine 100. The remote control server 540 also transmits an operation signal of the operating device 530 by the operator to the work machine 100 via the network. The remote control server 540 executes at least some of the functions of the control device 200 according to the above-described embodiment. That is, in a work system including the remote control server 540, the control device 200 and the remote control server 540 constitute the work system. Further, the work machine 100 according to another embodiment may be self-driving. For example, when construction data on site is input to the control device 200 via a communication line, the control device 200 determines an operation plan for the work machine 100 based on the construction data and the position and attitude of the own vehicle on site, and controls the work machine 100. At this time, the control device 200 determines the traveling speed so that the virtual wall VW and the work machine 100 do not come into contact with each other. Thereby, the control device 200 can control so that the work machine 100 does not enter the prohibited entry area.

[0071] Although a bucket is attached as the attachment 163 to the work implement 160 according to the first embodiment, it is not limited thereto. For example, the work implement 160 according to other embodiments may be provided with other working tools such as a breaker or a grapple instead of the bucket. Further, the attachment 163 according to other embodiments may be attached to the tip of the arm 162 via a tilt attachment or a tilt-rotate attachment.

[0072] The control device 200 according to the first embodiment simulates the outer shells of the arm bottom, the arm top, and the attachment 163 with a virtual sphere VS to identify the distance from the virtual wall VW, but is not limited thereto. For example, the working machine 160 according to other embodiments may identify the position of the outer shell using geometry data indicating the positions of a plurality of points (control points) on the outer shells of the arm bottom, the arm top, and the attachment 163.

Explanation of Reference Numerals

[0073] 100... Construction machine 101... Inclinometer 102... Swing angle sensor 103... Boom angle sensor 104... Arm angle sensor 105... Attachment angle sensor 106... Position and orientation detector 111... Power source 112... Hydraulic pump 113... Control valve 114... Travel motor 115... Swing motor 116... Boom cylinder 117... Arm cylinder 118... Attachment cylinder 119... Imaging device 120... Travel body 121... Crawler 140... Swing body 141... Operating device 142... Monitor device 160... Working machine 161... Boom 162... Arm 163... Attachment 180... Operator's cab 200... Control device 210... Processor 211... Operation signal receiving unit 212... Input unit 213... Display control unit 214... Measured value receiving unit 215... Position specifying unit 218... Intervention determination unit 219... Intervention control unit 220... Control signal output unit 230... Main memory 250... Storage 270... Interface 500... Remote operation device 510... Driver's seat 520... Display 530... Operating device 540... Remote operation server VW... Virtual wall

Claims

1. A system for controlling a work machine, comprising: a processor, wherein the processor identifies a virtual wall that is a surface for prohibiting entry into the work machine, and controls the traveling speed of the work machine based on the identified virtual wall. The system.

2. The processor controls the traveling speed so that the virtual wall and the work machine do not come into contact with each other. The system according to claim 1.

3. The processor controls the traveling speed based on the distance between the outer shell of the work machine and the virtual wall. The system according to claim 1.

4. The work machine includes a pair of left and right traveling devices, and the processor controls the traveling speed based on at least one of the operation directions of the pair of left and right traveling devices and the operation amounts of the pair of left and right traveling devices. The system according to claim 3.

5. The processor controls the traveling speed so that the virtual wall and the work machine do not come into contact with each other when both of the pair of left and right traveling devices are operated in a direction approaching the virtual wall. The system according to claim 4.

6. The processor does not limit the traveling speed when both of the pair of left and right traveling devices are operated in a direction away from the virtual wall. The system according to claim 4.

7. The processor identifies a portion of the outer shell of the work machine that approaches the virtual wall when the operation directions of the pair of left and right traveling devices are different from each other, and controls the traveling speed based on the distance between the identified portion and the virtual wall. The system according to claim 4.

8. The processor identifies the turning direction of the work machine by the pair of left and right traveling devices based on the operation directions of the pair of left and right traveling devices, and based on the identified turning direction, a portion of the outer shell that intersects a plane passing through the virtual wall, an axis extending in the front-rear direction of the work machine body, and an axis extending in the left-right direction, and is closer to the virtual wall than a plane passing through the midpoint of the pair of left and right traveling devices, and on the side where there is a traveling device that rotates in a direction approaching the virtual wall is identified as the portion approaching the virtual wall. The system according to claim 7.

9. The processor identifies a portion of the outer shell of the work machine that approaches the virtual wall when the operation amounts of the pair of left and right traveling devices are different, and controls the traveling speed based on the distance between the identified portion and the virtual wall. The system according to claim 4.

10. The processor Based on the operation amounts of the pair of left and right traveling devices, identify the turning direction of the work machine by the pair of left and right traveling devices. Based on the identified turning direction, among the outer shell, identify the portion on the side that intersects the virtual wall and the ground contact surfaces of the pair of left and right traveling devices and exists in the direction approaching the virtual wall from the plane passing through the midpoint of the pair of left and right traveling devices as the portion approaching the virtual wall. The system according to claim 9.

11. The pair of left and right traveling devices are a pair of left and right crawlers. The system according to claim 4.

12. The processor Determine an allowable speed based on the distance between the outer shell of the work machine and the virtual wall. Receive the operation amounts for each of the pair of left and right traveling devices. Calculate a target speed for each of the pair of left and right traveling devices based on the allowable speed and the operation amounts. Control the traveling speed so that the ratio of the commanded speed indicated by the operation amount related to the first traveling device among the pair of left and right traveling devices to the target speed is equal to the ratio of the commanded speed indicated by the operation amount related to the second traveling device among the pair of left and right traveling devices to the target speed. The system according to claim 4.

13. A method for controlling a work machine, comprising: Identifying a virtual wall that is a surface for prohibiting entry of the work machine. Controlling the traveling speed of the work machine based on the identified virtual wall. A method comprising the above.

14. On a computer for controlling a work machine, Identifying a virtual wall that is a surface for prohibiting entry of the work machine. Controlling the traveling speed of the work machine based on the identified virtual wall. A program for causing the above to be executed.

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