Working machine

Abstract

Provided is a working machine with which it is possible for a more appropriate operation to be selected in accordance with a surrounding environment and an operating mode when an obstacle is detected. The working machine is provided with an obstacle detecting sensor for detecting an obstacle, and a control device for controlling the working machine on the basis of a detection result from the obstacle detecting sensor, wherein the control device determines whether the obstacle should be bypassed, in accordance with a position of the working machine within a work site when the obstacle was detected, or an operating mode of the working machine when the obstacle was detected, and changes a control content of the working machine on the basis of the determination result.

Description

Work machinery

[0001] The present invention relates to a work machine.

[0002] Conventionally, work machines that perform predetermined operations to avoid collisions have been proposed (for example, Patent Document 1). Patent Document 1 describes a wheel loader that includes a sensor for measuring the distance between a dump truck and the boom of the wheel loader, and a controller for controlling the operation of the wheel loader. The controller described in Patent Document 1 controls predetermined operations to avoid collisions (raising the boom, stopping the wheel loader from traveling, and outputting a warning sound or display) when the distance between the dump truck and the boom becomes equal to or less than a threshold value due to the wheel loader traveling.

[0003] International Publication No. 2018 / 043104

[0004] A wheel loader performs two tasks: excavating soil and sand with a bucket and loading the excavated soil and sand onto a dump truck. During this series of wheel loader operations, soil and sand may spill onto the ground from the bucket. According to the technology described in Patent Document 1, an obstacle such as soil and sand measured by a sensor is recognized as a loading target, and if the distance between the soil and sand and the boom falls below a threshold, the wheel loader may stop traveling.

[0005] Meanwhile, there are a wide variety of surrounding environments and operating modes (operating conditions) that wheel loaders work in. For example, when a wheel loader is operating in a relatively large work area or when the wheel loader is traveling, it may be more appropriate to continue operating by detouring around earth and sand, etc., rather than stopping the operation of the wheel loader.

[0006] On the other hand, when the wheel loader is operating in a relatively narrow work area or when the wheel loader is excavating, it may be more appropriate to continue traveling over soil and sand rather than stopping the operation of the wheel loader.

[0007] With the technology described in Patent Document 1, there is a risk that the wheel loader will stop traveling in all cases when the distance between the soil or sand and the boom falls below a threshold, and it may not be possible to select a more appropriate operation depending on the surrounding environment or operating mode in which the wheel loader operates.

[0008] The present invention has been made in consideration of the above-mentioned problems, and its purpose is to provide a work machine that can select a more appropriate operation depending on the surrounding environment and operating mode when an obstacle is detected.

[0009] In order to achieve the above object, the work machine according to the present invention is a work machine equipped with an obstacle detection sensor that detects obstacles, and a control device that controls the work machine based on the detection results of the obstacle detection sensor, and is characterized in that the control device determines whether or not to detour around the obstacle depending on the position of the work machine within the work site when the obstacle is detected, or the operating mode of the work machine when the obstacle is detected, and changes the control content of the work machine based on the result of this determination.

[0010] According to the present invention, it is possible to provide a work machine that, when an obstacle is detected, selects a more appropriate operation depending on the surrounding environment and the operation mode.

[0011] 1 is a perspective view showing a schematic view of a work machine according to a first embodiment; a system configuration diagram showing a schematic view of a control system for a work machine according to the first embodiment; a functional block diagram of an automatic driving control device for a work machine according to the first embodiment; a plan view showing a schematic view of an example of a movement range of a work machine according to the first embodiment; a flowchart showing calculation processing executed by a behavior management unit of a work machine according to the first embodiment; a diagram showing an example of a process for determining an operation mode and a target position executed by a behavior management unit of a work machine according to a modified example of the first embodiment; a system configuration diagram showing a schematic view of a control system for a work machine according to a second embodiment; a functional block diagram of a notification control device for a work machine according to the second embodiment; a flowchart showing calculation processing executed by a notification management unit of a work machine according to a modified example of the second embodiment;

[0012] <First embodiment> A wheel loader V1 will be used as an example of a work machine according to a first embodiment of the present invention and will be described below with reference to the drawings. The schematic configuration of the wheel loader V1 and the system configuration of the control system according to this embodiment will be described with reference to Figures 1 and 2. Figure 1 is a perspective view that shows a schematic view of the wheel loader V1 according to the first embodiment. Figure 2 is a system configuration diagram that shows a schematic view of the control system for the wheel loader V1.

[0013] For ease of explanation, "front," "rear," "left," and "right" are defined based on the traveling direction of the wheel loader V1 shown in Fig. 1, and "up" and "down" are defined based on gravity. That is, the "front" and "rear" arrows shown in Fig. 1 indicate the forward and backward directions of the wheel loader V1, and the "up" and "down" arrows indicate the up and down directions of the wheel loader V1. The left and right (vehicle width) direction of the wheel loader V1 is defined as the direction perpendicular to the fore-aft and up and down directions described above.

[0014] The wheel loader V1 is a machine that uses a bucket 1 to excavate earth and sand, transport the excavated earth and sand, and load it onto a loading object R ( FIG. 4 ), such as a dump truck. As shown in FIG. 1 , the wheel loader V1 is equipped with a bucket 1, which is a working tool, and a lift arm 2 that rotatably supports the bucket 1, at the front side in the direction of travel. The lift arm 2 is rotatably supported on the vehicle body of the wheel loader V1. A bell crank 3 is rotatably supported on the lift arm 2. The bell crank 3 rotates the bucket 1 relative to the lift arm 2 via a bucket link 4.

[0015] As shown in FIGS. 1 and 2, the wheel loader V1 is equipped with a front right tire 21FR, a front left tire 21FL, a rear right tire 21RR, and a rear left tire 21RL, and travels by driving these tires.

[0016] The wheel loader V1 is also equipped with an articulated steering mechanism, and turns by creating an angular difference between the front and rear vehicle bodies around a center joint 23C extending in the vertical direction (up and down) of the vehicle body. In addition to creating an angular difference between the front and rear vehicle bodies of the wheel loader V1, the center joint 23C also has the function of distributing the driving force of the engine 10 to the front differential 24F and rear differential 24R, as will be described later.

[0017] The wheel loader V1 includes an engine 10 as a power source, a hydraulic pump 14 driven by the engine 10, and a driving force transmission device 22. The driving force of the engine 10 is transmitted to a center joint 23C via the driving force transmission device 22. The driving force of the engine 10 is distributed by the center joint 23C to a front differential 24F and a rear differential 24R.

[0018] The driving force of the engine 10 is then distributed to each tire (front left tire 21FL, front right tire 21FR, rear left tire 21RL, rear right tire 21RR) via the front differential 24F and rear differential 24R. This allows the wheel loader V1 to travel.

[0019] The hydraulic pump 14 is driven by the engine 10 to supply hydraulic oil to the control valve 15. The hydraulic oil is distributed by the control valve 15 and supplied to the steering cylinder 11, the lift cylinder 12, the bucket cylinder 13, and the brakes 14F and 14R.

[0020] The steering cylinder 11, lift cylinder 12, and bucket cylinder 13 each extend and contract using the supplied hydraulic oil, thereby changing the angle between the front and rear vehicle bodies, the angle of the lift arm 2 relative to the vehicle body, and the angle of the bucket 1 relative to the lift arm 2.

[0021] Furthermore, the brakes 14F, 14R are closed by the supplied hydraulic oil, which inhibits the rotation of each tire (front left tire 21FL, front right tire 21FR, rear left tire 21RL, rear right tire 21RR), causing the wheel loader V1 to slow down and come to a stop.

[0022] The wheel loader V1 also includes an automatic driving control device 100, an engine control device 500, a hydraulic control device 600, a driving control device 700, a communication interface 60, a moving object detection information receiving device (moving object acquisition device) 61, a positioning device 51, and an obstacle detection sensor 52.

[0023] As shown in FIG. 1 , the positioning device 51 includes a first positioning device 51R provided on the right side of the vehicle body above the wheel loader V1, and a second positioning device 51L provided on the left side of the vehicle body. The positioning device 51 is a well-known GNSS (Global Navigation Satellite System), but the positioning device 51 of this embodiment is not limited to this. For example, the positioning device 51 may be configured with a well-known SLAM (Simultaneous Localization and Mapping) using a camera or LiDAR. The positioning device 51 acquires position information of the wheel loader V1 and transmits the position information to the automatic driving control device 100.

[0024] The obstacle detection sensor 52 is provided on the front side above the body of the wheel loader V1. The obstacle detection sensor 52 detects obstacles around (for example, in front of) the wheel loader V1 and transmits information about the obstacles to the automatic driving control device 100. The obstacle detection sensor 52 may be any sensor that can detect obstacles, and may be configured, for example, with a known LiDAR or millimeter wave radar.

[0025] Obstacles in this embodiment are earth and sand that has spilled from the bucket 1 during excavation or loading work, and are objects whose positions cannot be stored in advance in the automatic driving control device 100. Objects whose positions can be stored in advance in the automatic driving control device 100, such as retaining walls that surround the excavation area A or loading area B, are not included in the obstacles of this embodiment. Furthermore, obstacles in this embodiment are objects that are unlikely to be damaged even if the wheel loader V1 comes into contact with them. Work machines other than the wheel loader V1 and the loading target R, workers, and the like (moving objects described below) are not included in the obstacles of this embodiment because there is a high possibility of damage if the wheel loader V1 comes into contact with them.

[0026] The communication interface 60 may be any device capable of acquiring communication information from the external process control terminal 800, and may be, for example, a wireless communication device attached to the wheel loader V1.

[0027] The process control terminal 800 is a terminal for transmitting communication information to each work machine at a work site. The process control terminal 800 may be a terminal in which a work site manager manually creates communication information and transmits that communication information. The process control terminal 800 may also be a terminal in which a sensor or the like is used to acquire the progress of work at the entire work site, automatically generate communication information, and transmit that communication information. Examples of communication information transmitted from the process control terminal 800 include map data (e.g., FIG. 4 ) showing the movement range of the wheel loader V1, the work content of the wheel loader V1 (excavation work, loading work, etc.), the number of work operations, the excavation position of the excavated material, and the loading position of the excavated material.

[0028] The mobile object detection information receiving device 61 is a device that acquires mobile object detection information indicating that a mobile object other than the wheel loader (host vehicle) V1 according to this embodiment has been detected, and is attached to the wheel loader V1. The mobile object detection information receiving device 61 acquires mobile object detection information from monitoring devices CA and CB that are installed in predetermined areas (excavation area A and loading area B) that will be described later. In this embodiment, a mobile object is a movable object other than the wheel loader V1 and the loading object R, and examples of such an object include a work machine (another wheel loader, etc.) or a worker.

[0029] In this embodiment, a case will be described in which the wheel loader V1 is provided with a mobile object detection information receiving device 61 separate from the communication interface 60, but the mobile object detection information receiving device 61 may be omitted by including mobile object detection information in the communication information acquired by the communication interface 60.

[0030] As shown in FIG. 2 , the automatic driving control device 100 acquires communication information transmitted from the process control terminal 800 via the communication interface 60, acquires moving object detection information via the moving object detection information receiving device 61, acquires position information of the wheel loader V1 via the positioning device 51, and acquires information on obstacles around the wheel loader V1 via the obstacle detection sensor 52.

[0031] Based on this information, the automatic driving control device 100 generates an engine control signal, a hydraulic control signal, and a driving control signal, and transmits these signals to the engine control device 500, the hydraulic control device 600, and the driving control device 700, respectively.

[0032] The engine control device 500 controls the rotation speed of the engine 10 based on the engine control signal. The hydraulic control device 600 controls the opening and closing degree of the control valve 15 based on the hydraulic control signal. The travel control device 700 controls the gear ratio and rotation direction of the driving force transmission device 22 based on the travel control signal.

[0033] Next, the functions of the automatic driving control device 100 according to this embodiment will be described with reference to Fig. 3. Fig. 3 is a functional block diagram of the automatic driving control device 100 for the wheel loader V1. The automatic driving control device 100 comprises a behavior management unit 110, a route planning unit 120, and an action generation unit 130. The behavior management unit 110 corresponds to the control device according to the present invention.

[0034] The behavior management unit 110 acquires communication information via the communication interface 60, acquires moving object detection information via the moving object detection information receiving device 61, acquires position information of the wheel loader V1 via the positioning device 51, acquires obstacle information via the obstacle detection sensor 52, and acquires information on operation completion determination from the operation generation unit 130.

[0035] The behavior management unit 110 determines the next operation mode of the wheel loader V1 based on the map data indicating the movement range of the wheel loader V1 included in the communication information, the position information, and the operation completion determination information, and transmits this operation mode to the operation generation unit 130. The operation mode of the wheel loader V1 indicates the manner in which the wheel loader V1 operates. The behavior management unit 110 can determine a traveling mode that is primarily focused on traveling operations, an excavation mode that is primarily focused on excavation operations, or a loading mode that is primarily focused on loading operations as the operation mode of the wheel loader V1 ( FIG. 6 ).

[0036] Furthermore, the behavior management unit 110 calculates a target position corresponding to the next operation mode of the wheel loader V1 based on the above position information and the above map data, and transmits a route planning command together with this target position to the route planning unit 120. The behavior management unit 110 calculates the vehicle position within the movement range of the wheel loader V1 by comparing the above position information with the above map data, and uses this vehicle position information when calculating the next operation mode and target position. Details of the calculation processing performed by the behavior management unit 110 will be described later using Figures 4 to 6.

[0037] The route planning unit 120 acquires the target position calculated by the behavior management unit 110 , acquires position information of the wheel loader V1 via the positioning device 51 , and acquires obstacle information via the obstacle detection sensor 52 .

[0038] When the route planning unit 120 receives a route planning command from the behavior management unit 110, it calculates a target route along which the wheel loader V1 should travel, and transmits this target route to the action generation unit 130. Here, the target route is a travel route of the wheel loader V1 from the position information acquired via the positioning device 51, i.e., the current position of the wheel loader V1, to the target position calculated by the behavior management unit 110, and is calculated as a travel route that does not interfere with obstacles acquired via the obstacle detection sensor 52. When the route planning unit 120 receives a route planning command from the behavior management unit 110, it calculates a target route, and the target route is updated each time.

[0039] The operation generation unit 130 acquires the next operation mode of the wheel loader V1 determined by the behavior management unit 110, acquires the target route calculated by the route planning unit 120, acquires position information of the wheel loader V1 via the positioning device 51, and acquires obstacle information via the obstacle detection sensor 52.

[0040] The movement generation unit 130 generates a traveling movement of the wheel loader V1 so that the current position of the wheel loader V1 follows the target route, and transmits the generated traveling movement to the traveling control device 700 as a traveling control signal.

[0041] Furthermore, the operation generator 130 generates a work operation of the bucket, such as digging or loading, according to the acquired operation mode, and transmits the generated work operation to the hydraulic control device 600 as a hydraulic control signal.

[0042] The motion generation unit 130 also calculates the rotation speed of the engine 10 required to realize the driving motion and working motion, and transmits it to the engine control device 500 as an engine control signal.

[0043] For example, similar to conventional manual operation, the travel control signal may be the amount of accelerator and brake pedal operation and a switching signal for a forward / reverse switch, and the hydraulic control signal may be the amount of operation of a lever that operates the lift arm 2 and a lever that operates the bucket 1.

[0044] When the wheel loader V1 reaches the end point of the target route (i.e., the target position) or when the work operation according to the acquired operation mode is completed, the operation generation unit 130 transmits information on the operation completion determination to the behavior management unit 110.

[0045] Furthermore, the action generation unit 130 may determine the size of the obstacle based on the obstacle information acquired via the obstacle detection sensor 52. In this case, the action generation unit 130 may estimate the degree of effect that the size of the obstacle will have on the traveling stability of the wheel loader V1 from the determination result, and may perform control to slow down the traveling speed of the wheel loader V1 or to stop its traveling.

[0046] For example, if the size of the obstacle is larger than a predetermined threshold, the action generation unit 130 stops the travel of the wheel loader V1. Furthermore, if the size of the obstacle is equal to or smaller than a predetermined threshold, the action generation unit 130 slows down the travel speed of the wheel loader V1. The threshold for the obstacle size is determined based on whether or not there is a possibility of the wheel loader V1 tipping over if it travels over the obstacle. Therefore, regardless of the results of the calculations performed by the behavior management unit 110 (described below), the calculations performed by the action generation unit 130 can select a more appropriate action according to the size of the obstacle.

[0047] Next, the contents of the calculation processing carried out in the behavior management unit 110 according to this embodiment will be described with reference to Fig. 4 to Fig. 6. Fig. 4 is a plan view showing an example of the movement range of the wheel loader V1. Fig. 5 is a flowchart showing the calculation processing executed in the behavior management unit 110 of the wheel loader V1. Fig. 6 is a diagram showing an example of the processing for determining the operation mode and target position executed in the behavior management unit 110 of the wheel loader V1.

[0048] As shown in FIG. 4, the movement range of the wheel loader V1 is defined as a plurality of coordinate points and the area surrounded by them in the map data included in the communication information transmitted from the process control terminal 800.

[0049] Specifically, the movement range of the wheel loader V1 according to this embodiment is made up of a movement area U surrounded by P1 to P4, an excavation area A surrounded by P11 to P14, and a loading area B surrounded by P21 to P24. The excavation area A includes the excavation object Q that is the object to be excavated by the wheel loader V1. The excavation area A is the area where the wheel loader V1 performs the work of excavating the excavation object Q, and is a work area with a limited size that is surrounded by a retaining wall or the like.

[0050] The loading area B includes a loading target R onto which the excavated material Q is to be loaded. The loading area B is an area where the wheel loader V1 performs the loading work of the excavated material Q, and is a work area surrounded by a retaining wall or the like and having a limited area. The excavation area A and the loading area B correspond to the predetermined area according to the present invention. Note that the predetermined area is not limited to the excavation area A and the loading area B, but it is preferable to set a work area having a limited area in terms of work or operation of the wheel loader V1 due to the presence of surrounding structures or areas where entry is prohibited.

[0051] The movement area U includes the standby position W of the wheel loader V1. The movement area U is an area in which the wheel loader V1 moves between the standby position W, the excavation area A, and the loading area B, and is an area larger than the excavation area A and the loading area B.

[0052] The wheel loader V1 travels through the movement area U from the standby position W to the excavation area A, and excavates the excavated object Q in the excavation area A. Thereafter, the wheel loader V1 travels through the movement area U from the excavation area A to the loading area B, with the excavated object Q held in the bucket 1, and loads the excavated object Q onto the loading target R in the loading area B.

[0053] After loading is complete, the wheel loader V1 repeats excavation in the excavation area A and loading in the loading area B until all of the excavated materials Q have been loaded onto the loading target R. When all of the excavated materials Q have been loaded onto the loading target R, the wheel loader V1 travels through the movement area U and returns to the standby position W.

[0054] Monitoring devices CA, CB are installed in the excavation area A and the loading area B, and these monitoring devices CA, CB monitor for the intrusion of moving objects (workers, other wheel loaders, etc.). The monitoring devices CA, CB are monitoring cameras that detect moving objects other than the wheel loader V1 in the excavation area A and the loading area B, and transmit the detection results to a moving object detection information receiving device 61 as moving object detection information. The monitoring devices CA, CB may also acquire position information of the wheel loader V1 acquired by the positioning device 51. This makes it easier for the monitoring devices CA, CB to distinguish between the wheel loader V1 and moving objects other than the wheel loader V1.

[0055] Here, a feature of the excavation area A and loading area B according to this embodiment is that at least a part of these areas is smaller than the minimum turning diameter of the wheel loader V1, making it difficult for the wheel loader V1 to turn within the excavation area A and loading area B. Furthermore, the excavation area A and loading area B may be areas where the intrusion of moving objects is monitored by monitoring devices CA, CB.

[0056] 5, the behavior management unit 110 determines whether a moving object other than the wheel loader (host vehicle) V1 (e.g., a worker or another wheel loader) has been detected in the excavation area A or the loading area B based on the moving object detection information transmitted from the monitoring devices CA and CB (S1101). If the behavior management unit 110 determines that a moving object has been detected (YES in S1101), the behavior management unit 110 stops the operation of the wheel loader V1 (S1108). Thereafter, this calculation process returns to the start. Therefore, regardless of the current position or operation mode of the wheel loader V1, if a moving object other than the wheel loader V1 enters the excavation area A or the loading area B, the operation of the wheel loader V1 can be stopped, and the wheel loader V1 can be prevented from coming into contact with the moving object.

[0057] On the other hand, if the behavior management unit 110 determines that no moving object has been detected (NO in S1101), the calculation process proceeds to S1102. In S1102, the behavior management unit 110 determines whether a predetermined operation (e.g., traveling, digging, or loading) corresponding to a predetermined operation mode has been completed.

[0058] Specifically, when the behavior management unit 110 receives information on the determination of motion completion from the motion generation unit 130, it determines that the predetermined motion has been completed (YES in S1102). Then, the calculation process proceeds to S1103. On the other hand, when the behavior management unit 110 does not receive information on the determination of motion completion from the motion generation unit 130, it determines that the predetermined motion has not been completed (NO in S1102). Then, the calculation process proceeds to S1105.

[0059] In S1103, the behavior management unit 110 determines the next operation mode for the wheel loader V1. Specifically, the behavior management unit 110 determines the next operation mode for the wheel loader V1 based on the table shown in Fig. 6 in accordance with the current position of the wheel loader V1 and the operation mode corresponding to the completed operation.

[0060] For example, when the wheel loader V1 reaches excavation area A in traveling mode, the current position is excavation area A, and the completed operation mode is traveling mode. Therefore, the behavior management unit 110 determines the excavation mode as the next operation mode (see the top row of Figure 6). At this time, the behavior management unit 110 selects the excavation target position as the target position for the wheel loader V1.

[0061] Furthermore, when the wheel loader V1 completes the excavation mode in excavation area A, the current position is excavation area A, and the completed operation mode becomes excavation mode. Therefore, the behavior management unit 110 determines the traveling mode as the next operation mode (see the second from the top in Figure 6). At this time, the behavior management unit 110 selects the loading area B as the target position for the wheel loader V1. Explanation of the bottom and second from the bottom in Figure 6 will be omitted. Thereafter, this calculation process proceeds to S1104.

[0062] In S1104, the behavior management unit 110 sends a route planning command to the route planning unit 120 to plan a target route from the current position of the wheel loader V1 to the target position to which the wheel loader V1 should move. After that, this calculation process returns to the start.

[0063] In S1105, the behavior management unit 110 determines whether or not an obstacle (such as earth and sand) has been detected around the wheel loader V1 based on the obstacle information acquired via the obstacle detection sensor 52. If the behavior management unit 110 determines that the above-mentioned obstacle has not been detected (NO in S1105), the present calculation process proceeds to S1107.

[0064] In S1107, the behavior management unit 110 does not update the target route for the wheel loader V1 (i.e., does not send a route planning command to the route planning unit 120), and continues the operation corresponding to the current operating mode of the wheel loader V1 (for example, traveling mode, etc.). After that, this calculation process returns to the start.

[0065] On the other hand, if the behavior management unit 110 determines that the obstacle has been detected (YES in S1105), the calculation process proceeds to S1106.

[0066] In step S1106, the behavior management unit 110 determines whether or not the current position of the wheel loader V1 is in a predetermined area (i.e., excavation area A or loading area B). If the behavior management unit 110 determines that the current position is in a predetermined area (YES in S1106), the calculation process proceeds to S1107, and if it determines that the current position is not in a predetermined area (NO in S1106), the calculation process proceeds to S1104.

[0067] The behavior management unit 110 controls the wheel loader V1 based on the detection results of the obstacle detection sensor 52. Specifically, in S1104 and S1107 after S1106, the behavior management unit 110 determines whether or not to detour around the obstacle depending on the position of the wheel loader V1 when the obstacle was detected, and changes the control content of the wheel loader V1 based on the result of this determination.

[0068] Specifically, if the position of the wheel loader V1 when the obstacle is detected is within a predetermined area (YES in S1106), in S1107 the behavior management unit 110 determines that the obstacle should not be detoured, and continues the operation of the wheel loader V1 when the obstacle was detected. In other words, the behavior management unit 110 does not update the target route of the wheel loader V1 (i.e., does not send a route planning command to the route planning unit 120), and performs control to continue the operation corresponding to the current operating mode of the wheel loader V1 (for example, excavation mode). After that, this calculation process returns to the start.

[0069] At least a portion of the excavation area A and the loading area B is smaller than the minimum turning diameter of the wheel loader V1, and so there is not enough space to detour around the obstacle. However, as in this embodiment, if the current position of the wheel loader V1 when an obstacle is detected is in a predetermined area, not updating the target path of the wheel loader V1 can prevent, for example, contact with a retaining wall or the like due to unnecessary steering operation.

[0070] Furthermore, even if excavated material Q such as earth and sand that has fallen to the ground in the excavation area A or the loading area B is detected as an obstacle, it is possible to continue operation corresponding to the current operation mode of the wheel loader V1. When performing an excavation operation corresponding to the excavation mode in the excavation area A, and when performing a loading operation corresponding to the loading mode in the loading area B, the wheel loader V1 travels at a relatively low speed, so it is possible to overcome obstacles such as earth and sand and continue the operation, and work by the wheel loader V1 can be carried out efficiently.

[0071] On the other hand, if the position of the wheel loader V1 when the obstacle is detected is outside the predetermined area (NO in S1106), in S1104 the behavior management unit 110 determines that the obstacle should be bypassed, and generates a travel route that bypasses the obstacle.

[0072] In other words, if the position where an obstacle such as earth and sand is detected is within the movement area U, the behavior management unit 110 performs control to update the target route of the wheel loader V1 so as to bypass the obstacle (i.e., sends a route planning command to the route planning unit 120 to generate a travel route). Thereafter, this calculation process returns to the start.

[0073] The movement area U is larger than the excavation area A and the loading area B, and therefore has sufficient space to go around obstacles. When performing a traveling operation corresponding to the traveling mode in the movement area U, the wheel loader V1 travels at a relatively high speed, and by going around the obstacle, the risk of tipping over when going over an obstacle such as earth and sand at high speed can be avoided.

[0074] <Modification of First Embodiment> Next, a modification of the wheel loader V1 according to the first embodiment will be described. The wheel loader according to this modification differs from the wheel loader V1 described above in terms of the function of the behavior management unit. Below, components having the same or similar functions as the wheel loader V1 according to the first embodiment will be assigned the same reference numerals as the wheel loader V1 and their description will be omitted, and only the different parts will be described.

[0075] Figure 7 is a flowchart showing the calculation processing executed by the behavior management unit of the work machine according to the modified example of Embodiment 1. As shown in Figure 7, if the behavior management unit determines that an obstacle has been detected (YES in S1105), the calculation processing proceeds to S1106a.

[0076] In S1106a, the behavior management unit determines whether the operation mode of the wheel loader is a predetermined operation mode. Here, the predetermined operation mode is an excavation mode in which excavation material Q is excavated, or a loading mode in which the excavated material Q is loaded.

[0077] If the behavior management unit determines that the operation mode is a predetermined operation mode (YES in S1106a), the calculation process proceeds to S1107, and if it determines that the operation mode is not a predetermined operation mode (NO in S1106a), the calculation process proceeds to S1104. In S1104 and S1107 after S1106a, the behavior management unit determines whether or not to detour around the obstacle depending on the operation mode of the wheel loader V1 when the obstacle was detected, and changes the control content of the wheel loader V1 based on the determination result.

[0078] Specifically, if the operation mode of the wheel loader when an obstacle is detected is a predetermined operation mode (excavation mode or loading mode) (YES in S1106a), in S1107 the behavior management unit determines that the obstacle should not be detoured, and continues the operation of the wheel loader V1 when the obstacle was detected. In other words, the behavior management unit does not update the target route of the wheel loader (i.e., does not send a route planning command to the route planning unit), and performs control to continue the operation (for example, excavation operation) corresponding to the current operation mode of the wheel loader (for example, excavation mode, etc.). Then, this calculation process returns to the start.

[0079] When the wheel loader performs an operation corresponding to the excavation mode or loading mode, the wheel loader travels at a relatively slow speed, which makes it possible for the wheel loader to overcome obstacles such as earth and sand and continue the operation regardless of the area in which it is working, allowing the wheel loader to work efficiently.

[0080] On the other hand, if the operation mode of the wheel loader when an obstacle is detected is not a predetermined operation mode (excavation mode or loading mode) (NO in S1106a), in S1104 the behavior management unit determines that the obstacle should be bypassed and generates a travel route that bypasses the obstacle. For example, if the operation mode when an obstacle such as earth and sand is detected is a travel mode, the behavior management unit performs control to update the target route of the wheel loader so that the obstacle is bypassed (in other words, it sends a route planning command to the route planning unit to generate a travel route). Then, this calculation process returns to the start.

[0081] A wheel loader in travel mode travels at a higher speed than a wheel loader in excavation mode or loading mode, so by going around the obstacle, the risk of tipping over when going over an obstacle such as earth and sand at high speed can be avoided.

[0082] <Second embodiment> Next, a wheel loader according to a second embodiment of the present invention will be described with reference to Figures 8 to 10. The wheel loader according to this embodiment differs from the wheel loader according to the first embodiment in that, instead of the automatic driving control device 100, it is equipped with a steering wheel 31, a work implement operation lever 32, a brake pedal 33, an accelerator pedal 34, and a shift operation lever 35 for manually operating the wheel loader, and further in that a notification control device 200 and an alarm (notification device) 53 are added. Hereinafter, components having the same or similar functions as those of the wheel loader V1 described above will be assigned the same reference numerals as those of the wheel loader V1, and description thereof will be omitted, and only different parts will be described.

[0083] Figure 8 is a system configuration diagram that shows, in outline, the control system for a wheel loader according to the second embodiment. As shown in Figure 8, the hydraulic control device 600 controls the degree of opening and closing of the control valve 15 in accordance with the amount of operation of the steering wheel 31, the work implement operation lever 32, and the brake pedal 33. The engine control device 500 controls the rotation speed of the engine 10 in accordance with the amount of operation of the accelerator pedal 34. The travel control device 700 controls the gear ratio and rotation direction of the driving force transmission device 22 in accordance with the operation of the shift operation lever 35.

[0084] The notification control device 200 acquires communication information transmitted from the process control terminal 800 via the communication interface 60, acquires position information of the wheel loader via the positioning device 51, and acquires information on obstacles around the wheel loader via the obstacle detection sensor 52.

[0085] The notification control device 200 generates a notification control signal based on this information and transmits this signal to the alarm 53. The alarm 53 may notify the operator using a volume, melody, light intensity, message, color, or the like. As an example, the alarm 53 may be capable of changing the intensity of the notification to the operator, and may be, for example, a rotating light. When the alarm 53 is a rotating light, the intensity of the notification is changed by changing the volume or pitch (frequency) of the sound, the brightness or darkness of the light, the rotation speed, or the like. Note that in this embodiment, a rotating light is used as an example of the alarm 53, but a monitor that displays the position of an obstacle may also be used as the alarm 53. In this case, the intensity may be changed by changing the contrast, color, frequency (flashing speed), or the like when flashing the obstacle position display.

[0086] Next, the function of the notification control device 200 according to this embodiment will be described with reference to Fig. 9. Fig. 9 is a functional block diagram of the notification control device 200 of a wheel loader according to the second embodiment. The notification control device 200 comprises a notification management unit 210 and a notification signal generation unit 220. The notification management unit 210 corresponds to the control device according to the present invention.

[0087] The notification management unit 210 acquires communication information via the communication interface 60, acquires wheel loader position information via the positioning device 51, and acquires obstacle information via the obstacle detection sensor 52. The notification management unit 210 determines a notification mode based on map data indicating the wheel loader's movement range included in the communication information, the position information, and the obstacle information, and transmits the notification mode to the notification signal generation unit 220. Details of the calculation processing performed by the notification management unit 210 will be described later.

[0088] The notification signal generation unit 220 acquires the notification mode determined by the notification management unit 210, generates a notification control signal based on the notification mode, and transmits the notification control signal to the alarm 53. The notification signal generation unit 220 controls the notification control signal to change the intensity of the notification by the alarm 53, such as a rotating light.

[0089] Next, the content of the calculation processing carried out in the notification management unit 210 according to this embodiment will be described with reference to Fig. 10. Fig. 10 is a flowchart showing the calculation processing executed in the notification management unit 210 of the wheel loader according to the second embodiment.

[0090] 10 , the notification management unit 210 determines whether or not an obstacle (such as earth and sand) has been detected around the wheel loader based on the obstacle information acquired via the obstacle detection sensor 52 (S2101). If the notification management unit 210 determines that the obstacle has not been detected (NO in S2101), the calculation process returns to the start. On the other hand, if the notification management unit 210 determines that the obstacle has been detected (YES in S2101), the calculation process proceeds to S2102.

[0091] In S2102, the notification management unit 210 calculates the current position within the movement range of the wheel loader by comparing the position information of the wheel loader acquired via the positioning device 51 with the map data included in the communication information, and determines whether or not this current position is in a predetermined area (i.e., excavation area A or loading area B).

[0092] If the notification management unit 210 determines that the current position is within a predetermined area (YES in S2102), the calculation process proceeds to S2103, and if it determines that the current position is not within a predetermined area (NO in S2102), the calculation process proceeds to S2104. In S2103 and S2104, the notification management unit 210 determines whether or not to bypass the obstacle depending on the position of the wheel loader when the obstacle was detected, and changes the control content of the wheel loader based on the result of this determination.

[0093] Specifically, if the position of the wheel loader when an obstacle is detected is within a predetermined area (YES in S2102), in S2103 the notification management unit 210 determines that the obstacle should not be detoured, and weakens the intensity of the notification by the annunciator 53 compared to when the position of the wheel loader when the obstacle is detected is outside the predetermined area. In other words, the notification management unit 210 decides on a notification mode in which the obstacle notification is weak, and transmits this notification mode to the notification signal generation unit 220. If the annunciator 53 is a rotating light, the notification management unit 210 decides on a notification mode in which a low-pitched sound (low volume, low frequency) or a dim, slow rotation (low volume, low frequency) is emitted.

[0094] On the other hand, if the position of the wheel loader when an obstacle is detected is outside the predetermined area (NO in S2102), in S2104 the notification management unit 210 determines that the obstacle should be detoured, and increases the intensity of the notification by the annunciator 53 compared to when the position of the wheel loader when the obstacle is detected is within the predetermined area. In other words, the notification management unit 210 determines a notification mode in which the obstacle notification is strong, and transmits this notification mode to the notification signal generation unit 220. If the annunciator 53 is a rotating light, the notification management unit 210 determines a notification mode in which a loud, high-pitched sound (large volume, high frequency) or a bright, high-speed rotation (large volume, high frequency) is emitted.

[0095] In this way, if the current position of the wheel loader when an obstacle is detected is in a predetermined area (digging area A or loading area B), the notification management unit 210 performs control to weaken the intensity of the notification by the alarm 53. As a result, even if excavated material Q such as earth and sand that has fallen to the ground in a predetermined area is detected as an obstacle, the annoyance of the notification given to the operator can be reduced. Therefore, the operator can concentrate on the operation corresponding to the current operating mode of the wheel loader (digging mode, loading mode) without having to go around obstacles such as earth and sand, and can perform work using the wheel loader efficiently.

[0096] On the other hand, if the current position of the wheel loader when an obstacle is detected is outside the specified area (travel area U), the notification management unit 210 performs control to increase the intensity of the notification by the alarm 53. Therefore, if excavated material Q such as earth and sand that has fallen to the ground in the travel area U is detected as an obstacle, it is possible to provide the operator with an opportunity to take action to detour around the obstacle.

[0097] <Modification of Second Embodiment> Next, a modification of the wheel loader according to the second embodiment will be described. The wheel loader according to this modification differs from the wheel loader according to the second embodiment in the function of the notification management unit. Below, configurations that have the same or similar functions as the wheel loader according to the second embodiment will be assigned the same reference numerals as the wheel loader, and a description of those configurations will be omitted, and only the different parts will be described.

[0098] Fig. 11 is a flowchart showing the calculation process executed by the notification management unit of the work machine according to the modified example of Embodiment 2. As shown in Fig. 11, when the notification management unit determines that an obstacle has been detected (YES in S2101), the calculation process proceeds to S2102a.

[0099] In S2102a, the notification management unit determines whether the operation mode of the wheel loader is a predetermined operation mode (excavation mode or loading mode). The notification management unit calculates the current position within the movement range of the wheel loader by comparing the position information of the wheel loader acquired via the positioning device 51 with the map data included in the communication information, and estimates the operation mode of the wheel loader based on this current position. For example, if the current position of the wheel loader is calculated to be in excavation area A, the notification management unit estimates that the operation mode of the wheel loader is excavation mode.

[0100] Similarly, if the current position of the wheel loader is calculated to be in loading area B, the notification management unit will estimate that the operation mode of the wheel loader is loading mode. If the current position of the wheel loader is calculated to be in traveling area U, the notification management unit will estimate that the operation mode of the wheel loader is traveling mode.

[0101] If the notification management unit determines that the operation mode is a predetermined operation mode (YES in S2102a), the calculation process proceeds to S2103, and if it determines that the operation mode is not a predetermined operation mode (NO in S2102a), the calculation process proceeds to S2104. In S2103 and S2104, the notification management unit 210 determines whether or not to detour around the obstacle depending on the operation mode of the wheel loader when the obstacle was detected, and changes the control content of the wheel loader based on the result of this determination.

[0102] Specifically, if the operating mode of the wheel loader when an obstacle is detected is a predetermined operating mode (YES in S2102a), in S2103 the notification management unit determines that the obstacle should not be detoured, and weakens the intensity of the notification by the annunciator 53 compared to when the operating mode of the wheel loader when an obstacle is detected is outside the predetermined operating mode. In other words, the notification management unit decides on a notification mode in which obstacle notification is weak, and transmits this notification mode to the notification signal generation unit 220.

[0103] In this way, if the operation mode of the wheel loader when an obstacle is detected is a predetermined operation mode (excavation mode or loading mode), the notification management unit performs control to weaken the intensity of the notification by the alarm 53. When performing operations corresponding to excavation mode or loading mode, the wheel loader travels at a relatively slow speed, so even if excavated material Q such as earth and sand that has fallen to the ground is detected as an obstacle while in that mode, the annoyance of the notification given to the operator can be reduced. Therefore, the operator can concentrate on operations corresponding to the current operation mode of the wheel loader (digging mode, loading mode) without having to go around obstacles such as earth and sand, and can perform work using the wheel loader efficiently.

[0104] On the other hand, if the operation mode of the wheel loader when an obstacle is detected is not a predetermined operation mode (NO in S2102a), in S2104 the notification management unit determines that the obstacle should be detoured, and increases the intensity of the notification by the annunciator 53 compared to when the wheel loader was in a predetermined operation mode when the obstacle was detected. In other words, if the operation mode when an obstacle such as earth and sand is detected is the traveling mode, the notification management unit determines a notification mode in which to issue a strong obstacle notification, and transmits this notification mode to the notification signal generation unit 220.

[0105] A wheel loader in travel mode travels at a higher speed than a wheel loader in excavation mode or loading mode, so when excavated material Q such as earth and sand that has fallen to the ground in the travel area U is detected as an obstacle, it can provide the operator with an opportunity to operate to bypass the obstacle. By bypassing the obstacle, it is possible to avoid the risk of tipping over when driving over an obstacle such as earth and sand at high speed.

[0106] While the preferred embodiments of the present invention have been described above, the present invention is not limited to the wheel loaders according to the above embodiments, and includes all aspects encompassed within the concept and scope of the claims of the present invention. For example, while the above-described embodiments apply the present invention to wheel loaders equipped with buckets as working implements, the application of the present invention is not limited to this, and it can also be applied to work machines other than wheel loaders, such as hydraulic excavators.

[0107] Furthermore, the above-described embodiments have been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to those including all of the described configurations. Furthermore, each configuration may be appropriately and selectively combined to achieve the above-described problems and effects. For example, the shape, material, arrangement, size, etc. of each component in the above-described embodiments may be appropriately changed depending on the specific aspects of the present invention.

[0108] CA, CB Monitoring camera (monitoring device) A Excavation area (predetermined area) B Loading area (predetermined area) V1 Wheel loader (work machine) 52 Obstacle detection sensor 53 Alarm (alarm device) 61 Moving object detection information receiving device (moving object acquisition device) 110 Action management unit (control device) 210 Notification management unit (control device)

Claims

1. A work machine that performs work and moves at a work site, the work machine comprising: an obstacle detection sensor that detects surrounding obstacles; and a control device that controls the work machine based on the detection results of the obstacle detection sensor; The control device includes: control the operation of the work machine based on information indicating a position of the work machine, a work area in which the work machine performs an excavation operation to excavate an excavated material or a loading operation to load the excavated material at the work site, and a movement area in which the work machine moves, and the detection results of the obstacle detection sensor; If the position of the work machine when the obstacle is detected is within the working area, it is determined that the obstacle should not be detoured, and the operation when the obstacle was detected is continued; If the position of the work machine when the obstacle is detected is within the movement area, it is determined that the obstacle should be detoured, and a traveling operation for detour- ing around the obstacle is performed. A working machine characterized by:

2. (delete)

3. (delete)

4. a mobile object acquisition device that acquires information about a mobile object other than the work machine in the work area from a monitoring device installed in the work area, The control device stops the operation of the work machine based on the information of the moving object acquired from the moving object acquisition device.

2. A work machine according to claim 1.

5. a notification device that notifies the user that the obstacle has been detected; When the position of the work machine when the obstacle is detected is within the working area, the control device weakens the intensity of the notification by the notification device compared to when the position of the work machine when the obstacle is detected is within the moving area.

2. A work machine according to claim 1.

6. (delete)

7. A work machine that performs work and moves at a work site, the work machine comprising: an obstacle detection sensor that detects surrounding obstacles; and a control device that controls the work machine based on the detection results of the obstacle detection sensor; The control device includes: determining a next operation mode of the work machine based on the operation mode completed by the work machine and the position of the work machine when the operation mode was completed, and controlling the operation of the work machine based on the determined next operation mode and the detection result of the obstacle detection sensor; If the operation mode when the obstacle is detected is a predetermined operation mode, it is determined that the obstacle should not be detoured, and the operation when the obstacle is detected is continued; If the operation mode when the obstacle is detected is not the predetermined operation mode, it is determined that the obstacle should be bypassed, and a traveling operation for bypassing the obstacle is performed. A working machine characterized by:

8. (delete)

9. a notification device that notifies the user that the obstacle has been detected; When the operation mode when the obstacle is detected is a predetermined operation mode, the control device weakens the intensity of the notification by the notification device compared to when the operation mode when the obstacle is detected is not the predetermined operation mode.

8. A work machine according to claim 7.

10. The predetermined operation mode is a digging mode for digging an excavated material or a loading mode for loading the excavated material. A work machine according to claim 7 or 9.

11. The control device determines a next operation mode of the work machine based on a relationship between a predetermined operation mode completed by the work machine, a position of the work machine when the operation mode is completed, and a next operation mode of the work machine.

10. A work machine according to claim 9.