Control device for work machine

Abstract

To provide a control device for a work machine equipped with a work implement, capable of realizing efficient excavation by preventing the work implement from interfering with the ground surface, since a bucket may interfere with excavation topography during manual or automatic excavation, resulting in inefficient excavation operation.SOLUTION: An operation of a work implement is controlled so that an interference range set on a bucket 10 does not interfere with an excavation topography, which is a topography shape changed by an excavation operation of the work implement.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a control device that controls excavation of a work machine. [Background technology]

[0002] 2. Description of the Related Art There has been proposed a work machine such as a hydraulic excavator that assists in excavation work.

[0003] For example, Patent Document 1 proposes a control device that plans a target path for a work implement (hereinafter also referred to as a work device or a bucket) equipped on a work machine according to a predetermined excavation curve ratio, and controls the work implement along the target path.

[0004] In addition, Patent Document 2 proposes a control device that obtains the force (hereinafter referred to as the excavation reaction force) that the soil exerts on the bucket based on the ground depth and previously input soil characteristics, and determines whether or not the excavation operation needs to be modified depending on whether the excavation reaction force is greater than a predetermined upper limit value. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 7088792 [Patent Document 2] Patent No. 5519414 Summary of the Invention [Problem to be solved by the invention]

[0006] According to Patent Document 1, a target excavation path for a work implement provided in a work machine can be generated and control can be performed along the target excavation path. According to Patent Document 2, the excavation operation can be corrected according to the excavation load.

[0007] However, it is difficult to say that the control methods of Patent Documents 1 and 2 fully consider conditions suitable for excavation when controlling the bucket angle. For example, if the bucket angle is increased in the crowding direction during excavation, the bucket may interfere with the excavation topography formed by previous excavation. For example, if the back surface (bottom surface) of the bucket interferes with the excavation topography (see FIG. 20), the reaction force acting on the back surface of the bucket from the excavation topography increases, resulting in excessive consumption of hydraulic energy, or the vehicle body is lifted up, making the vehicle body's posture unstable, making it difficult to say that excavation is efficient.

[0008] The present invention has been made in consideration of the above, and aims to provide a control device for a work machine equipped with a work implement that can avoid interference between the work implement and the ground and achieve efficient excavation. [Means for solving the problem]

[0009] In order to solve the above problems, the control device for a work machine of the present invention is a control device for a work machine equipped with a multi-jointed working device having a bucket, and the control device calculates an excavation topography, which is the topography shape changed by the excavation operation of the working device, based on shape information of the bucket, dimensional information of the working device, and attitude information of the working device, and controls the operation of the working device so that the interference range set on the bucket does not interfere with the excavation topography. Effect of the Invention

[0010] According to the present invention, efficient excavation can be achieved without interference between the working device and the excavation topography.

[0011] Problems, configurations and effects other than those described above will become apparent from the following description of the embodiments. [Brief description of the drawings]

[0012] [Figure 1] 1 is a perspective view of a hydraulic excavator equipped with a control system including a control device (controller) of the present invention. [Diagram 2] FIG. 1 is a system diagram of a control system according to a first embodiment of the present invention. [Diagram 3] 1 is an example of the geometry of a working device. [Figure 4] An example of the interference range of a work device. [Diagram 5] 4 is a flowchart of a target path planning calculation unit of a controller according to the first embodiment of the present invention. [Figure 6] An example of when problems with the surrounding terrain may occur (when the selected target route is complex). [Figure 7] An example of a case where a problem occurs with the surrounding terrain (when digging starts and hits the surrounding terrain). [Figure 8] An example of the topographic shape measured by a topographical measuring device. [Figure 9] FIG. 1 is a system diagram of a hydraulic system (hydraulic circuit) according to a first embodiment of the present invention. [Figure 10] FIG. 2 is an example of an internal block diagram of a target path tracking unit of a controller according to the first embodiment of the present invention (when configured with only feedforward). [Figure 11] 4 is an example of a flowchart of a target path tracking unit of a controller according to the first embodiment of the present invention (when configured with only feedforward). [Figure 12] 13 is a specific example of a target angle extracted by the plan extraction unit. [Figure 13] 13 shows a specific example of coefficients for an actuator speed calculation unit. [Figure 14] FIG. 2 is an example of an internal block diagram of a target path tracking unit of a controller according to the first embodiment of the present invention (when using feedback). [Figure 15] 4 is an example of a flowchart of a target path tracking unit of a controller according to the first embodiment of the present invention (when feedback is used). [Figure 16] 13 is a specific example of a target angle extracted by the plan extraction unit. [Figure 17] FIG. 11 is a system diagram of a control system according to a second embodiment of the present invention. [Figure 18] 10 is a flowchart of a terrain estimation unit and an operation intervention unit of a controller according to a second embodiment of the present invention. [Figure 19]13 is an example of calculation of topographical information (excluding the overlapped volume and the area directly above it) by the topographical estimation unit according to the second embodiment of the present invention. [Figure 20] Schematic diagram of what happens when the back (bottom) of the bucket interferes with the excavation terrain. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In each drawing, parts having the same function are designated by the same reference numerals, and repeated description may be omitted.

[0014] Although the embodiment of the present invention is described with respect to a backhoe-type shovel, the present invention can be applied to general work machines capable of moving earth and sand with a work implement including a bucket, specifically, general shovels such as loading-type shovels, two-piece shovels, offset shovels, wheel loaders, skid steer loaders, etc.

[0015] [Example 1] The first embodiment relates to a control system that automatically performs an excavation operation.

[0016] <Overall composition> FIG. 1 is a perspective view of a hydraulic excavator 1 equipped with a control system including a control device (controller) of the present invention.

[0017] A hydraulic excavator (hereinafter simply referred to as an excavator) 1 includes a lower traveling body 1C, an upper rotating body 1B rotatably attached to the lower traveling body 1C via a rotating device 4, and an articulated front 1A attached to the upper rotating body 1B. The front 1A includes a boom 8 rotatably attached to the upper rotating body 1B, an arm 9 rotatably attached to the boom 8, a bucket rotatably attached to the arm 9, a bucket link 13 rotatably attached to the bucket 10 and the arm 9, a boom cylinder 5 connected to the boom 8 and the upper rotating body 1B and changing the rotation angle of the boom 8 and the upper rotating body 1B, an arm cylinder 6 connected to the boom 8 and the arm 9 and changing the rotation angle of the boom 8 and the arm 9, and a bucket cylinder 7 connected to the arm 9 and the bucket link 13 and changing the rotation angle of the bucket 10 via the bucket link 13. The lower traveling structure 1C is equipped with a track mechanism driven by a traveling motor 3, enabling the vehicle body to move. The rotating device 4 is composed of a rotating motor 11 that changes the rotation angle of the lower traveling structure 1C and the upper rotating structure 1B. A controller 20 equipped with the control system of the present invention and an input device 25 are provided on the upper rotating structure 1B. In FIG. 1, the upper rotating structure 1B is provided with an operation device 2 that allows an operator to operate the boom 8, arm 9, and bucket 10, and a display device 27, but these components will be described in Example 2.

[0018] The control system of the present invention may be configured via wireless communication or the like as long as it can calculate the excavation path, and all components do not need to be mounted on the vehicle body. For example, instead of the controller 20 and the input device 25, a communication terminal may be provided on the work machine (shovel 1), and the control system, its calculation device, and input device may be external.

[0019] The shovel 1 has a boom angle measuring device 21a provided on the boom 8 and measuring the relative rotation angle between the upper rotating body 1B and the boom 8, an arm angle measuring device 21b provided on the arm 9 and measuring the relative rotation angle between the boom 8 and the arm 9, and a bucket angle measuring device 21c provided on the bucket 10 and measuring the rotation angle between the arm 9 and the bucket 10.

[0020] Note that the angle and angular velocity measuring device is assumed to be an angle sensor and is described as an angle measuring device, but as long as it can measure and calculate the relative angle, the form is not important, and the relative angle may be calculated based on the ground angle measured by an IMU (Inertial Measurement Unit) or the like.

[0021] The shovel 1 also has a topography measuring device 22 that is provided on the upper rotating body 1B and is capable of measuring the topography of the area excavated by the bucket 10.

[0022] In consideration of blind spots caused by the front 1A, a plurality of topography measuring devices 22 may be provided.

[0023] Furthermore, the topography measuring device 22 may be any device capable of measuring the surface shape of the topography, such as Lidar or a stereo camera.

[0024] <Configuration of controller 20> FIG. 2 is a system diagram of a control system mounted on the controller 20 of this embodiment.

[0025] The control system includes, in the input device 25, a geometric shape input unit 201 for inputting the geometric shape (geometric information) of the bucket 10 as a working implement, and an interference range input unit 203 for inputting an interference range that represents the shape of the range in which interference with the terrain should be avoided from the geometric shape inputted in the geometric shape input unit 201. Note that specific numerical values ​​may be directly inputted into the geometric shape input unit 201 and the interference range input unit 203 of the working implement, or may be selected from a list created in advance. Specific examples of the geometric shape and interference range of the working implement will be described in the explanation of the operation.

[0026] Furthermore, the control system includes, in the controller 20, a mechanism information recording unit 208 that records mechanism information that is the lengths of the boom 8 and the arm 9, a target path planning calculation unit 202 that plans a target path for the boom 8, arm 9, and bucket 10 using the topographical shape measured by the topography measuring device 22, the geometrical shape and interference range of the work device input by the geometrical shape input unit 201 and the interference range input unit 203, and the mechanism information recorded in the mechanism information recording unit 208, and a target path following unit 209 that calculates solenoid valve commands to solenoid valves 62, 63, 64 (FIG. 9) to control the boom 8, arm 9, and bucket 10 so as to follow the target path planned by the target path planning calculation unit 202.

[0027] In this embodiment, the target path refers to data on the relative angles of the boom 8, the arm 9, and the bucket 10 in chronological order.

[0028] 3 shows the geometric information of the bucket 10 input by the geometric shape input unit 201. The geometric information of the bucket 10 is composed of a plurality of points on the bucket 10, a plurality of lines connecting the points, and a surface surrounded by the plurality of lines, and is a shape that approximates part of the shape of the bucket 10 with a rectangular prism so as to include the tines and sides of the bucket 10. As shown in FIG. 3, the vertices of the shape that approximates the bucket 10 with a rectangular prism are called Pos. 1 to 4 and 5 to 8 in the counterclockwise direction from the corner near the tip of the tines.

[0029] In this embodiment, the geometric information is approximated by a quadrangular prism. However, in consideration of the calculation speed, any curved shape such as a polygonal prism or mesh data may be used, and the calculation method described below may be appropriately modified.

[0030] 4 shows the interference range of the bucket 10 input by the interference range input unit 203. The interference range of the bucket 10 is composed of a plurality of points on the bucket 10, a plurality of lines connecting the points, and a surface surrounded by the plurality of lines, and is a shape that approximates part of the shape of the bucket 10 with a triangular prism and does not overlap with the geometric information of the bucket 10. As shown in FIG. 4, the vertices of the shape that approximates the bucket 10 with a triangular prism are called Pos. 1_2 to 3_2, 4_2 to 6_2 in a counterclockwise direction from the corner near the tip position. Note that, like the geometric information, the shape of the interference range may be any shape, such as a polygonal prism.

[0031] <Operation of controller 20> FIG. 5 is a flowchart of the target path planning calculation unit 202 of the controller 20 of this embodiment.

[0032] The flowchart in FIG. 5 performs calculations for each progress rate t so as to prevent interference between the bucket 10 and the excavation topography, which is the topographical shape that has changed due to the excavation operation of the bucket 10 up to the progress rate t, and performs optimization.

[0033] The optimization method of S501 to S512 can be any method that optimizes the path relative to the relative angles of the boom 8, arm 9, and bucket 10. For example, the path can be approximated by a polynomial (S501), and the optimization parameters can be determined as shown in Equations 1 to 3 (S502).

[0034]

number

[0035] The relative angle θ of the boom 8, arm 9, and bucket 10 defined by the formulas 1 to 3 bm_t ,θ am_t ,θ bk_t A loop calculation is performed for the progress rate t (S503). The loop is appropriately determined based on the calculation speed and accuracy of the computer within the range of the progress rate t.

[0036] First, according to Equations 1 to 3, the relative angle θ of the boom 8, the arm 9, and the bucket 10 at the current progress rate t is calculated. bm_t, θ am_t , θ bk_t is calculated (S504).

[0037] Next, as shown in Equation 4, the geometric information of the bucket 10 (the coordinates P 1~8 ) and the relative angle θ bm_t , θ am_t , θ bk_t Based on this, the position P of the geometric information of bucket 10 at the current progress rate t i ' is calculated (S505).

[0038]

number

[0039] T in Equation 4 is a coordinate transformation matrix (a forward kinematics transformation, for example, a homogeneous transformation matrix) calculated from the lengths recorded in the mechanism information recording unit 208 of the boom 8, the arm 9, and the bucket 10.

[0040] Next, from the topographical shape of the previous progress rate, P i The shape (calculation of Boolean difference) excluding the solid (overlapping portion of the geometric information of bucket 10) constituted by ' is set as the topographical shape at the progress rate t (S506).

[0041] Next, similarly to Equation 4, the position Q of the interference range of bucket 10 is i (Coordinate Q of Pos.1_2~6_2 in Fig. 4) 1~6 ) and the relative angle θ bm_t , θ am_t , θ bk_t Based on this, the position Q of the interference range of bucket 10 at the current progress rate t is i ' is calculated (S507).

[0042] The topographic shape and Q at the progress rate t calculated in S506 i ' is the volume excluding the solids composed of the terrain shape and the interference range (i.e., the overlapping volume of the terrain shape and the interference range) at the current progress rate t. t (S508).

[0043] S504 to S508 are calculated for all progress rates from 0 to 1 (S503 to S511).

[0044] Finally, the evaluation value J is calculated according to the formula 5 (S512). The optimization parameters are calculated so that the evaluation value J becomes the minimum (=0). In this way, a target route is planned that is determined to have no interference between the excavation topography and the interference range of the bucket 10, in other words, that the interference range of the bucket 10 is not smaller than the excavation topography (does not interfere).

[0045]

number

[0046] For example, in Patent Document 1, a downward convex route is determined depending on the curvature, and a bucket angle is set to a certain degree relative to the excavation curve, thereby making it possible to avoid collision with the terrain.

[0047] However, in actual terrain, the terrain is often not flat, so a route that allows for upward convexities may be more appropriate.

[0048] For example, in the case of Figure 6, if you try to excavate to the same depth as the current ground surface, you will end up excavating a path that is convex upward. The technology in Patent Document 1 allows only paths that are convex downward, so it is not possible to derive such a path.

[0049] Furthermore, in actual situations, the terrain is often not flat, and so there are cases where the terrain and the bucket interfere with each other when excavation begins.

[0050] For example, in the case of FIG. 7, with the technology of Patent Document 1, depending on the combination of the terrain shape, the curvature of the target route, and the angle of the bucket relative to the excavation curve, the terrain and the bucket may collide at the start of excavation.

[0051] For example, Fig. 8 shows an example of the terrain shape measured by the terrain measuring device 22. As shown in Fig. 8, if the range of the terrain shape measured by the terrain measuring device 22 includes at least the range in which the bucket 10 operates according to the plan, it is possible to reliably avoid interference between the terrain and the interference range of the bucket 10 as shown in Fig. 6 and Fig. 7.

[0052] Next, the target path tracking unit 209 of the controller 20 of this embodiment will be described with reference to FIGS.

[0053] FIG. 9 is a system diagram of a hydraulic system (hydraulic circuit) which is the means (the downstream actuator control means in FIG. 2) for realizing the target flow rate in this embodiment.

[0054] The hydraulic system 50 includes a tank 52 for storing hydraulic oil, a pump 51 that is driven by a prime mover (not shown) such as an engine to pressurize the hydraulic oil in the tank 52 and supply pressurized oil to the hydraulic system 50, a regulator 57 that controls the discharge flow rate of the pump 51, a relief valve 53 that is connected between the pump 51 and the tank 52 and limits the maximum value of the supply pressure, a spool valve 54 that controls the supply and discharge of pressurized oil to the boom cylinder 5 in response to the pilot pressure received at pressure receiving parts A1 and A2, and a pressure regulator 55 that controls the supply and discharge of pressurized oil to the arm cylinder 6 in response to the pilot pressure received at pressure receiving parts B1 and B2. the pilot pressure oil in response to a command from the controller 20 (solenoid valve command), and generating pilot pressures acting on the pressure receiving portions (A1, A2), (B1, B2), (C1, C2) of the spool valves 54, 55, 56. The pilot pressure oil in response to a command from the controller 20 (solenoid valve command) is reduced in pressure and acts on the pressure receiving portions (A1, A2), (B1, B2), (C1, C2) of the spool valves 54, 55, 56. The pilot pressure oil in response to a command from the controller 20 (solenoid valve command) is reduced in pressure and acts on the pressure receiving portions (A1, A2), (B1, B2), (C1, C2) of the spool valves 54, 55, 56.

[0055] The spool valves 54, 55, 56 can control the flow rate and direction of pressurized oil supplied to the actuators, boom cylinder 5, arm cylinder 6, and bucket cylinder 7, respectively, in accordance with the pilot pressure controlled by the controller 20, thereby controlling the movement of the boom 8, arm 9, and bucket 10.

[0056] In this embodiment, the operating speed and direction of the actuator are controlled by controlling the pilot pressure, but any form may be used as long as the operating speed and direction of the actuator can be controlled by commands from the controller 20, such as the spool valves 54, 55, 56 themselves being solenoid valves controlled by commands from the controller 20, or the actuators (all or part of them) being electrically powered.

[0057] <When configured with feedforward only> Fig. 10 is an example of an internal block diagram of the target path tracking unit 209 in Fig. 2. The target path tracking unit 209 is composed of a plan extraction unit 1001, an angular velocity calculation unit 1002, an actuator velocity calculation unit 1003, a flow rate calculation unit 1004, and a solenoid valve operation unit 1005. Fig. 11 is a flowchart of the internal block diagram in Fig. 10.

[0058] After the target path planning calculation unit 202 completes the path planning, the target path following unit 209 sets the progress rate t to 0 and starts path following (S1101).

[0059] The target path tracking unit 209 calculates an update amount Δt of the progress rate based on the calculation cycle (calculation time) Δn of the controller and a predetermined k (S1102) (plan extraction unit 1001), and sequentially updates the progress rate t of the path plan for each cycle of the controller (S1108, S1109, S1110).

[0060] The value of k used in the calculation in S1102 may be any value as long as the actuator speed does not exceed a predetermined maximum value in the actuator speed calculation unit 1003 at the subsequent stage.

[0061] The target path tracking unit 209 calculates a target angle θ of the current progress rate t based on the target path planned by the target path planning calculation unit 202. act_t and the next target angle θ act_t+Δt (S1103) (plan extraction unit 1001) (specific example: see FIG. 12).

[0062] The target path tracking unit 209 calculates a target cylinder flow rate based on these target angles, mechanism design values, cylinder design values, etc. (S1104, S1105, S1106) (angular velocity calculation unit 1002, actuator velocity calculation unit 1003, flow rate calculation unit 1004) (also see FIG. 13), and calculates a command (solenoid valve command) to the solenoid valves 62, 63, 64 based on the target cylinder flow rate (S1107) (solenoid valve operation unit 1005).

[0063] When the target path following unit 209 determines that the plan has reached the end (t=1) (S1108), it determines that excavation is complete and stops the path following operation (S1111).

[0064] <When to use feedback> Fig. 14 is another example of the internal block diagram of the target path tracking unit 209 in Fig. 2. The target path tracking unit 209 is composed of a plan extraction unit 1401, an angular velocity calculation unit 1402, an actuator velocity calculation unit 1403, a flow rate calculation unit 1404, and a solenoid valve operation unit 1405. Fig. 15 is a flowchart of the internal block diagram in Fig. 14. In this case, an angle measurement device 21 consisting of a boom angle measurement device 21a, an arm angle measurement device 21b, and a bucket angle measurement device 21c is required.

[0065] After the route planning is completed, the target route tracking unit 209 sets the progress rate t to 0 and starts route tracking (S1501).

[0066] The target path tracking unit 209 extracts the current angle θ obtained from the angle measurement device 21 in the plan extraction unit 1401. act_sens Based on this, the target angle θ act_t is calculated (S1502, S1503).

[0067] Any method for calculating the target angle can be used as long as it is uniquely determined based on the current angle. For example, one method is to set the progress rate corresponding to the angle closest to the current angle in the route plan as the current progress rate t, and use a plan that is a predetermined number Δt2 ahead of that t (see Figure 16).

[0068] 14, or S1504 to S1511 in FIG. 15 are similar to the angular velocity calculation unit 1002, actuator velocity calculation unit 1003, flow rate calculation unit 1004, solenoid valve operation unit 1005 in FIG. 10, or S1104 to S1111 in FIG. 11, and therefore will not be described below.

[0069] Feedback allows deviations from the plan to be corrected at execution time, resulting in more accurate tracking of the plan than a feedforward-only configuration.

[0070] <Effects specific to the form> According to the first embodiment, by planning an excavation path based on the terrain shape and the geometric shape of the bucket 10 for each progress of excavation, it is possible to avoid interference between the excavation terrain formed by previous excavations and the bucket 10. As a result, efficient automatic excavation can be realized.

[0071] [Example 2] The second embodiment relates to a control system that intervenes in an operation signal from an operating device.

[0072] <Overall composition> The hydraulic excavator 1 of the second embodiment includes, in addition to the configuration of the first embodiment, an operation device 2 for an operator to operate a boom 8, an arm 9, and a bucket 10, and a display device 27 on an upper rotating body 1B (see FIG. 1).

[0073] The control system of this embodiment may be configured via wireless communication or the like as long as it is possible to intervene in the operation of the operator, and it is not necessary that all components are mounted on the vehicle body. For example, instead of the controller 20 and the input device 25, a communication terminal may be provided on the work machine (shovel 1), and the controller 20, the input device 25, and the operation device 2 may be externally located in a so-called remote control form.

[0074] <Configuration of controller 20> FIG. 17 is a system diagram of a control system mounted on the controller 20 of this embodiment.

[0075] In the control system, operation signals of the boom 8, arm 9, and bucket 10 are input from the operation device 2 to the operation intervention unit 602 of the controller 20. The control system includes, in the input device 25, a geometric shape input unit 201 for inputting the geometric shape (geometric information) of the bucket 10 as the working implement, and an interference range input unit 203 for inputting an interference range that expresses the shape of a range in which interference with the terrain should be avoided among the geometric shapes inputted in the geometric shape input unit 201. Note that specific numerical values ​​may be directly inputted to the geometric shape input unit 201 and the interference range input unit 203 of the working implement, or may be selected from a list created in advance. Specific examples of the geometric shape and interference range of the working implement are the same as those in the first embodiment.

[0076] Furthermore, the control system includes, in the controller 20, a mechanism information recording unit 208 that records mechanism information that is the lengths of the boom 8 and the arm 9, and a terrain estimation unit 601 that estimates terrain information from angle information obtained from the angle measurement device 21 (boom angle measurement device 21a, arm angle measurement device 21b, bucket angle measurement device 21c). The control system also includes an operation intervention unit 602 that calculates solenoid valve commands to solenoid valves 62, 63, 64 (FIG. 9) using the operation signal input from the operation device 2, the angle information (equivalent to posture information) obtained from the angle measurement device 21, the terrain information estimated by the terrain estimation unit 601, the geometric shape and interference range of the work device input from the geometric shape input unit 201 and the interference range input unit 203, and the mechanism information recorded in the mechanism information recording unit 208, and intervenes in the operation signals of the boom 8, arm 9, and bucket 10 (input by the operation device 2).

[0077] <Operation of controller 20> FIG. 18 is a flowchart showing the time-based operations of the terrain estimation unit 601 and the operation intervention unit 602 of the controller 20 of this embodiment.

[0078] The flowchart in FIG. 18 shows a process for calculating and intervening in the operation so that there is no interference between the bucket 10 and the excavation topography, which is the topographical shape that has changed due to the excavation operation of the bucket 10 from the start of excavation until a certain time.

[0079] First, steps S701 to S703, which are the processing of the topography estimation unit 601, will be described.

[0080] The terrain estimation unit 601 detects the current relative angle θ of the boom 8, the arm 9, and the bucket 10 from the angle measurement device 21. bm , θ am , θ bk is obtained (S701).

[0081] Next, based on the geometric shape of bucket 10, the position P i The calculation method is the same as that of the formula 4 in the first embodiment.

[0082] Finally, from the previous terrain information stored internally, P i The shape (calculated by Boolean difference) excluding the solid (overlapping part of the geometric information of bucket 10) composed of ' and the terrain excluding its immediate upper part are saved as new terrain information (S703). Figure 19 shows the overlapped volume and its immediate upper part.

[0083] Next, steps S704 to S709, which are the processing of the operation intervention unit 602, will be described.

[0084] The operation intervention unit 602 uses the terrain information (excavation terrain) obtained from the terrain estimation unit 601 and the interference range information of the bucket 10 to determine the maximum angle θ at which the bucket 10 does not interfere with the terrain (in other words, the interference range of the bucket 10 is determined not to be smaller than the excavation terrain). bk_max is calculated (S704). The calculation method may be, for example, a comprehensive calculation of angles within the bucket rotation range. The calculation of interference is a Boolean difference calculation, similar to S508 in the first embodiment. The maximum angle in this case is the angle at which the bucket 10 first interferes with the terrain when moved from the full dump state (state in which the bucket 10 is rotated to the maximum in the direction away from the upper rotating body 1B) to the cloud direction (direction approaching the upper rotating body 1B) (see FIG. 20).

[0085] Current angle θ of bucket 10 bk and maximum angle θ bk_max Compare the current bucket 10 angle θ bk is the maximum angle θ bk_max If it is smaller (S705), the interference range of the bucket 10 and the excavation topography do not interfere with each other, so the work machine is operated according to the operation signal from the operation device 2 (S706). bk is the maximum angle θ bk_max If it is equal to (S707), the operation signal is input to the bucket 10 so as to set the operation of the bucket 10 to 0 (stop) (S708). bk is the maximum angle θ bk_max If the distance is larger than θ, the interference range of the bucket 10 and the excavation topography will interfere with each other. bk is the maximum angle θ bk_maxThe bucket 10 is controlled to move in the dump direction (only) toward the dumping direction (S709). In addition, the equivalence determination in S707 is performed by adjusting the θ bk and maximum angle θ bk_max The absolute value of the difference between the two may be equal to or less than a predetermined value.

[0086] Next, in an operation intervention state (S708, S709) in which the operation signal from the operation device 2 is being intervened (in other words, the operation device 2 is intervening in the operation of the bucket 10), the display device 27 displays that the operation is being intervened (S710).

[0087] <Effects specific to the form> According to the second embodiment, during an excavation operation, the operation of the operator is intervened based on the shape of the terrain and the geometric shape of the bucket 10, thereby making it possible to avoid interference between the excavation terrain formed by previous excavation and the bucket 10. As a result, the excavation work of the operator can be more appropriately assisted.

[0088] [summary] As described above, the control device (controller 20) of this embodiment calculates the excavation topography, which is the topography shape changed by the excavation operation of the work device, based on the shape information of the bucket 10, the dimensional information of the work device, and the attitude information of the work device, and controls the operation of the work device so that the interference range set on the bucket 10 does not interfere with the excavation topography.

[0089] According to this embodiment, efficient excavation can be achieved without interference between the working device and the excavation topography.

[0090] The control device (controller 20) acquires the terrain shape from the terrain measuring device 22, plans a target route including target attitude information of the work device, controls the operation of the work device so as to follow the planned target route, and based on the shape information of the bucket 10, the dimensional information of the work device, the target attitude information of the work device, and the terrain shape, plans a target route such that the interference range does not interfere with the excavation terrain, and controls the operation of the work device so as to follow the target route (to operate along the target route).

[0091] According to this embodiment, efficient automatic excavation can be realized without interference between the working device and the excavation topography.

[0092] The control device (controller 20) inputs an operation signal from an operating device 2 that operates the work device, inputs the attitude information from an attitude detection device (angle measurement device 21) that detects attitude information of the work device, controls the operation of the work device based on the operation signal input from the operating device 2, calculates the excavation topography based on shape information of the bucket 10, dimensional information of the work device, and attitude information of the work device, and intervenes in the operation of the work device based on the operation signal from the operating device 2 so that the interference range does not interfere with the excavation topography. The control device (controller 20) calculates a maximum angle at which the interference range does not interfere with the excavation topography, and if the current angle of the work device is smaller than the maximum angle, operates the work device according to the operation signal of the operating device, if the current angle of the work device is the maximum angle, stops the operation of the work device, and if the current angle of the work device is greater than the maximum angle, operates the work device according to only the operation signal of the operating device in the direction in which the current angle of the work device approaches the maximum angle.

[0093] According to this embodiment, an efficient excavation assistance system can be realized in which the working device does not interfere with the excavation topography.

[0094] The control device (controller 20) includes a display device 27 that displays that the control device is intervening in the operation of the work device based on an operation signal from the operation device 2.

[0095] According to this embodiment, the operator can clearly confirm the timing when assistance is provided by the excavation assistance system.

[0096] The present invention is not limited to the above-described embodiment, and includes various modified forms. For example, the above-described embodiment has been described in detail to clearly explain the present invention, and is not necessarily limited to those including all of the configurations described. In addition, it is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. In addition, it is possible to add, delete, or replace a part of the configuration of each embodiment with another configuration.

[0097] In addition, each function of the controller in the above-mentioned embodiment may be realized in hardware by designing some or all of them as an integrated circuit, for example. Also, each function may be realized in software by a processor interpreting and executing a program that realizes each function. Information such as programs, tables, and files that realize each function may be stored in a storage device in the controller, a hard disk, a solid state drive (SSD), or a recording medium such as an IC card, an SD card, or a DVD. [Explanation of symbols]

[0098] 1. Hydraulic excavator (working machine) 1A Front (Work Equipment) 1B Upper rotating body 1C Undercarriage 2 Control device 3. Travel motor 4 Swivel 5 Boom cylinder 6 Arm Cylinder 7 Bucket Cylinder 8. Boom 9 Arm 10 Buckets 11 Swing motor 13 Bucket Link 20 Controller 21 Angle measurement device (attitude detection device) 22 Topographical measurement device 25 Input Devices 27 Display device

Claims

1. A control device for a work machine equipped with a multi-joint type work implement having a bucket, The control device calculates an excavation topography, which is the topography shape changed by the excavation operation of the work device, based on shape information of the bucket, dimensional information of the work device, and attitude information of the work device, and controls the operation of the work device so that the interference range set on the bucket does not interfere with the excavation topography.

2. The control device for a work machine according to claim 1, The control device acquires a topographical shape from a topographical measurement device, the control device plans a target path including target attitude information of the working device, and controls an operation of the working device so as to follow the planned target path; The control device plans a target route so that the interference range does not interfere with the excavation terrain based on shape information of the bucket, dimensional information of the work device, target attitude information of the work device, and the terrain shape, and controls the operation of the work device so as to follow the target route.

3. The control device for a work machine according to claim 1, the control device inputs an operation signal from an operation device that operates the working device, and inputs posture information from a posture detection device that detects posture information of the working device; The control device controls an operation of the working device based on an operation signal input from the operating device, The control device calculates the excavation terrain based on shape information of the bucket, dimensional information of the work device, and attitude information of the work device, and intervenes in the operation of the work device based on an operation signal from the operating device so that the interference range does not interfere with the excavation terrain.

4. The control device for a work machine according to claim 3, The control device calculates a maximum angle at which the interference range does not interfere with the excavation topography, and, when the current angle of the work device is smaller than the maximum angle, operates the work device in accordance with an operation signal of the operating device, when the current angle of the work device is the maximum angle, stops the operation of the work device, and, when the current angle of the work device is greater than the maximum angle, operates the work device in accordance with only the operation signals of the operating device in a direction that brings the current angle of the work device closer to the maximum angle.

5. The control device for a work machine according to claim 3, 13. A control device for a work machine, comprising: a display device that displays that the control device is intervening in the operation of the work device based on an operation signal from the operating device.

Images