Excavation machine

Abstract

To provide a technology for improving the work efficiency of automated excavation work.SOLUTION: A backhoe 100 includes a work arm device 10 having a bucket 20 and excavating earth and sand 1 with the bucket 20, a sensor attached to the work arm device 10 to detect the earth and sand 1, and a control device 60 to control the operation of the work arm device 10. Based on detection results of the sensor, the control device 60 determines the timing of transition from a pushing operation that moves the bucket 20 and includes a vertically downward component to a raking operation that moves the bucket 20 and includes a horizontal component, and the timing of transition from the raking operation to a scooping operation that moves the bucket 20 and includes a vertically upward component.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The disclosure herein relates to an excavator. [Background technology]

[0002] Due to the shortage of labor and heavy machinery, unmanned operation using heavy machinery is being considered. However, automation of excavation work, whose efficiency is highly dependent on the skill of the operator, tends to result in unstable excavation volume per excavation operation, resulting in an issue that the excavation volume per unit time is inferior to that of manned work.

[0003] A related technique is described, for example, in Patent Document 1. Patent Document 1 describes a bucket equipped with a soil amount detection device that can detect the amount of soil inside the bucket. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 03-208920 Summary of the Invention [Problem to be solved by the invention]

[0005] Patent Document 1 describes a configuration for detecting the amount of soil in the bucket, but does not describe a technology for stabilizing the amount of excavation in one excavation operation and improving the amount of excavation per unit time.

[0006] In view of the above circumstances, an object of one aspect of the present invention is to provide a technique for improving the work efficiency of automated excavation work. [Means for solving the problem]

[0007] An excavation device according to one embodiment of the present invention comprises a work arm device having a bucket and excavating an excavation target with the bucket; a sensor attached to the work arm device for detecting the excavation target; and a control device for controlling the operation of the work arm device, which determines, based on the detection results of the sensor, the timing of transition from a first operation including a vertically downward component that moves the bucket to a second operation including a horizontal component that moves the bucket, and the timing of transition from the second operation to a third operation including a vertically upward component that moves the bucket. [Effects of the Invention]

[0008] According to the above aspect, it is possible to provide a technique for improving the work efficiency of automated excavation work. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a diagram illustrating a configuration of an excavator according to an embodiment; [Figure 2] FIG. 2 is an example of a block diagram of a configuration related to automatic excavation control of an excavator. [Figure 3] 4 is a flowchart showing an example of a control process performed by a control device of an excavator. [Figure 4] FIG. 3 is a diagram for explaining an example of a first sensor provided in the excavator. [Figure 5] FIG. 10 is a diagram illustrating a state of a bucket that is not sufficiently filled with soil and sand. [Figure 6] 10A and 10B are diagrams illustrating another state of the bucket in which the soil is not sufficiently filled. [Figure 7] FIG. 10 is a diagram illustrating a state of a bucket fully filled with soil and sand. [Figure 8] FIG. 4 is a diagram for explaining an example of a second sensor provided in the excavator. [Figure 9] FIG. 10 is a diagram for explaining another example of a second sensor provided in the excavator. [Figure 10] FIG. 10 is a diagram for explaining still another example of a second sensor provided in the excavator. [Figure 11]FIG. 1 is a diagram illustrating a configuration of a system according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Fig. 1 is a diagram illustrating the configuration of a backhoe 100, which is an excavator according to one embodiment. Fig. 2 is an example of a block diagram of a configuration related to automatic excavation control of the backhoe 100 shown in Fig. 1. The configuration of the backhoe 100 will be described below with reference to Figs. 1 and 2.

[0011] The backhoe 100 is an excavator equipped with a working arm device 10, a sensor 50, and a control device 60. The working arm device 10 includes a bucket 20, an arm 30 that rotatably supports the bucket 20, and a boom 40 that rotatably supports the arm 30, and uses the bucket 20 to excavate earth and sand 1, which is the excavation target.

[0012] Sensor 50 is a sensor that detects earth and sand 1 to be excavated, and is attached to work arm device 10. Sensor 50 includes sensor 51 that detects the vertical positional relationship between bucket 20 and the surface of earth and sand 1, and sensor 52 that detects the presence of earth and sand 1 in a predetermined area within bucket 20. Control device 60 controls the operation of work arm device 10 based on the detection results of sensor 50.

[0013] The backhoe 100 configured as described above is configured so that the control device 60 controls the operation of the working arm device 10 based on the detection results of the sensor 50, thereby achieving high work efficiency in automated excavation work.

[0014] Fig. 3 is a flowchart showing an example of control processing performed by the control device 60 of the backhoe 100. Fig. 4 is a diagram for explaining an example of a first sensor possessed by the backhoe 100. Figs. 5 and 6 are diagrams illustrating the state of the bucket 20 when it is not sufficiently filled with soil 1. Fig. 7 is a diagram illustrating the state of the bucket 20 when it is sufficiently filled with soil 1. Fig. 8 is a diagram for explaining an example of a second sensor possessed by the backhoe 100. The automated excavation work in the backhoe 100 will be explained in further detail below.

[0015] The movements of the working arm device 10 during excavation work can be broken down into (A) landing, (B) pushing, (C) raking, (D) (E) scooping, and (F) end of excavation and turning, as shown in Figure 1. Performing these steps smoothly enables efficient excavation.

[0016] (A) Landing and (B) pushing are operations that move the bucket 20 mainly in the vertically downward direction. In other words, they are operations that include a vertically downward component that moves the bucket, and are examples of the first operation of the working arm device 10.

[0017] (C) Scraping is an operation of moving the bucket 20 mainly in the horizontal direction, more specifically, toward the near side in the horizontal direction (toward the crawler of the backhoe 100). In other words, it is an operation that includes a horizontal component of moving the bucket, and is an example of the second operation of the working arm device 10.

[0018] (D) (E) Scooping up is an operation that mainly moves the bucket 20 in the vertically upward direction. In other words, it is an operation that includes a vertically upward component that moves the bucket, and is an example of a third operation of the working arm device 10.

[0019] (F) End of excavation & swing is an operation of moving the bucket 20 mainly in the horizontal direction, more specifically, an operation of swinging the bucket in the horizontal direction. In other words, it is an operation that includes a horizontal component of swinging the bucket, and is an example of the fourth operation of the working arm device 10.

[0020] In the backhoe 100, the control device 60 controls the above-mentioned operation of the work arm device 10 based on a pre-generated excavation model, thereby automating the excavation work. The excavation model is a model that controls the operation of the work arm device 10 so as to fill the bucket 20 with soil 1 during excavation work based on the surface shape of the given soil 1, and is, for example, a deep learning machine learning model. The control device 60 acquires information on the three-dimensional shape of the surface of the soil 1 obtained by a measuring device (not shown) at or before the start of the automatic excavation work, and controls the operation of the work arm device 10 by inputting the three-dimensional information into the excavation model.

[0021] The above-described excavation model is designed to fill bucket 20 with soil 1, but even when operating according to the excavation model, bucket 20 may not be sufficiently filled with soil 1. One possible reason for this is the fluidity of the excavation target (soil 1), that is, changes in the distribution of soil 1 that occur during excavation work. Furthermore, even if the excavation model takes fluidity into consideration, situations may arise where bucket 20 is not sufficiently filled with soil 1 due to other factors, such as the fact that fluidity varies depending on the type of soil 1, that the coordinate origin of the model cannot be fixed unlike industrial robots used in factories, and that the environment in which it is used is unknown and may change even during excavation work.

[0022] Taking this into consideration, in the backhoe 100, the control device 60 corrects the motion control by the excavation model based on the detection results of the sensor 50, and controls the motion of the working arm device 10. Specifically, the control device 60 determines the transition timing from the first motion to the second motion and the transition timing from the second motion to the third motion based on the detection results of the sensor 50, thereby correcting the motion control by the excavation model and controlling the motion of the working arm device 10. The control processing performed by the control device 60 will be described in detail below.

[0023] 3, when the control device 60 starts the control process, first, as shown in Fig. 3, it controls the operation of the working arm device 10 to make the working arm device 10 perform a pushing operation (first operation) following a landing operation on the surface of the soil 1 (step S1). After that, the control device 60 determines whether the detection result of the sensor 50 satisfies a first condition or not in order to decide whether to transition the operation of the working arm device 10 from the pushing operation to a raking operation (second operation) (step S2).

[0024] In step S2, control device 60 determines the timing to transition from the pushing operation to the scooping operation based on the detection result of sensor 51. Bucket 20 is rotatably connected to arm 30 via connection part 22 shown in FIG. 4. Sensor 51 is arranged on the edge of bucket 20 on the arm 30 side, facing teeth 21 (claws) of bucket 20, and detects the distance from sensor 51 to the surface of soil 1. Control device 60 determines the timing to transition from the pushing operation to the scooping operation based on the distance from the arm 30 side of bucket 20 to the soil 1.

[0025] Then, when the sensor 51 detects the surface of the earth and sand 1 within a predetermined distance (for example, 10 cm), the control device 60 shifts the operation of the working arm device 10 from the pushing operation to the raking operation. That is, the first condition of step S2 is that the distance from the sensor 51 to the surface of the earth and sand 1 is within a predetermined distance.

[0026] The distance to the surface of the soil 1 detected by sensor 51 enables control device 60 to determine how deeply bucket 20 is buried in soil 1. Therefore, by constantly monitoring the output from sensor 51, control device 60 can detect the process by which bucket 20 is gradually buried in soil 1, and can detect a state in which bucket 20 is buried appropriately, neither too shallowly nor too deeply. By shifting the operation of work arm device 10 from a pushing operation to a shoveling operation at that timing, soil 1 can be sufficiently shoveled into bucket 20 without excessive load.

[0027] If the transition timing is too early, the raking operation will be performed before the bucket 20 is fully inserted into the soil 1, and the raking operation will not be able to collect enough of the soil 1 into the bucket 20. On the other hand, if the transition timing is too late, the bucket 20 will be buried deep in the soil 1, and the raking operation will place a large load on the work arm device 10.

[0028] The sensor 51 does not require a very high level of accuracy. The accuracy of the sensor 51 needs to be about 10 mm, and therefore the sensor 51 may be any of ultrasonic, optical, or radio wave sensors, or may be any other sensor that measures distance from an image. Furthermore, multiple sensors 51 (for example, two or three) may be attached to the bucket 20, and the detection result of any of these may be used as the distance to the surface of the soil 1, or the results of statistical processing (average, maximum, minimum, median) of these may be used as the distance to the surface of the soil 1.

[0029] It is desirable for the sensor 51 to detect the shortest distance to the surface of the soil and sand 1, and the precise angle of the sensor 51 arranged toward the teeth 21 of the bucket 20 may be adjusted as appropriate. Furthermore, if the working arm device 10 is separately equipped with an angle sensor that detects the angle of the bucket 20, the control device 60 may calculate the shortest distance to the soil and sand surface from the detection result (angle information) of the angle sensor and the detection result (distance information) of the sensor 51, and when the shortest distance is within a predetermined distance, the operation of the working arm device 10 may be shifted from a pushing operation to a raking operation.

[0030] When the operation of the working arm device 10 shifts from the pushing operation to the scooping operation, the control device 60 controls the operation of the working arm device 10 to cause the working arm device 10 to perform the scooping operation (second operation) (step S3). After that, the control device 60 determines whether the detection result of the sensor 50 matches a second condition or not in order to decide whether to shift the operation of the working arm device 10 from the scooping operation to a scooping operation (third operation) (step S4).

[0031] In step S4, the control device 60 determines the timing of transition from the raking operation to the scooping operation based on the detection result of the sensor 52. The sensor 52 is a sensor (not shown) that detects the presence of earth and sand 1 in a predetermined area 53 in the bucket 20 shown in FIGS. 5 to 7. As shown in FIG. 8, the sensor 52 is a mechanical switch that turns ON when earth and sand 1 is present in the predetermined area 53. As shown in FIGS. 5 to 7, the predetermined area 53 is an area near the edge of the bucket 20 that is closer to the arm 30 (connection portion 22) than a position 51p corresponding to a predetermined distance that is compared with the distance detected by the sensor 51 in step S2. In this example, the predetermined area 53 is an area slightly spaced from the edge of the bucket 20 that is closer to the arm 30, but it may also be the edge itself. The control device 60 determines the timing of transition from the raking operation to the scooping operation based on whether earth and sand is present in the predetermined area 53.

[0032] Then, when the sensor 52 detects the presence of earth and sand 1 in the predetermined area 53, the control device 60 shifts the operation of the working arm device 10 from the shoveling operation to the scooping operation. That is, the second condition of step S4 is that earth and sand 1 is present in the predetermined area 53.

[0033] Based on the presence or absence of soil 1 in the predetermined area 53 detected by sensor 52, control device 60 can estimate the degree to which soil 1 is filled in bucket 20 after scooping up the soil. Even if the scooping operation is started after detecting the surface of soil 1 at position 51p in step S2, if the scooping operation is started in step S5 (described later) while soil 1 is not present in predetermined area 53 during the scooping operation in step S3, soil 1 will not be sufficiently filled in bucket 20 after scooping up, as shown in FIG. 5, due to insufficient scooping. Note that FIG. 6 shows the state of bucket 20 after the scooping operation when the scooping operation is started before the surface of soil 1 is detected at position 51p in step S2. In this case, the percentage of soil filled in bucket 20 will be even lower.

[0034] In contrast, in step S2, the surface of the soil 1 is detected at position 51p before proceeding to the scraping operation, and then, during the scraping operation in step S3, the presence of soil 1 in a specified area 53 is detected before proceeding to the scooping operation in step S5, thereby ensuring that sufficient soil 1 is scraped in, and as shown in Figure 7, the bucket 20 is sufficiently filled with soil 1 after scooping.

[0035] In this way, if sensor 52 detects earth and sand 1 in predetermined area 53 during the raking operation, it can be inferred that bucket 20 will be sufficiently filled with earth and sand 1 after scooping up the bucket 20, and if earth and sand 1 is not detected in predetermined area 53 during the raking operation, it can be inferred that bucket 20 will not be sufficiently filled with earth and sand 1 after scooping up the bucket 20. Therefore, when sensor 52 detects the presence of earth and sand 1 in predetermined area 53, control device 60 transitions the operation of work arm device 10 from the raking operation to the scooping operation.

[0036] When the operation of the working arm device 10 shifts from the raking operation to the scooping operation, the control device 60 controls the operation of the working arm device 10 to have the working arm device 10 perform a scooping operation (third operation) (step S5). When the scooping operation is completed, the control device 60 causes the working arm device 10 to perform a swing operation (step S6), and the excavated earth and sand 1 is loaded into a dump truck or the like, completing one excavation operation. In the backhoe 100, the control device 60 repeats the control processing shown in Figure 3 as many times as necessary, thereby automating the excavation work.

[0037] The backhoe 100 configured as described above improves the amount of excavation per run, thereby improving the overall work efficiency of automated excavation work. More specifically, the backhoe 100 determines the timing of the transition from the first operation to the second operation based on the detection results of the sensor 50, thereby preventing the bucket 20 from being insufficiently pushed into the soil. This avoids a situation in which the bucket 20 does not reach an appropriate depth relative to the soil surface, resulting in the bucket 20 being insufficiently filled with soil. Furthermore, the backhoe 100 determines the timing of the transition from the second operation to the third operation based on the detection results of the sensor 50, thereby preventing the bucket 20 from being insufficiently shoveled with soil. This avoids a situation in which the bucket 20 is scooped up before the soil has sufficiently entered the bucket 20, resulting in the bucket 20 being insufficiently filled with soil.

[0038] Furthermore, the backhoe 100 can improve the overall work efficiency of automated excavation work by preventing excessive load from being placed on the work arm device 10. More specifically, the backhoe 100 determines the timing of transition from the first operation to the second operation based on the detection results of the sensor 50, thereby preventing the bucket 20 from being pushed too far into the soil. This prevents the bucket 20 from being buried too deeply in the soil, which would result in excessive load being placed on the subsequent operation. Furthermore, the backhoe 100 determines the timing of transition from the second operation to the third operation based on the detection results of the sensor 50, thereby preventing a situation in which the raking operation is performed longer than necessary, resulting in unnecessary load being placed on the backhoe 100. Furthermore, if the raking operation is performed longer than necessary, soil will accumulate at the feet of the backhoe 100 (near the crawler), which is outside the excavable area. By controlling the backhoe 100 based on the detection results of the sensor 50, such a situation that reduces work efficiency can be avoided.

[0039] Therefore, according to the backhoe 100, by improving the filling rate of the bucket 20 during automated excavation work, the number of excavation and loading operations can be reduced, and the amount of work done per hour can be increased, thereby shortening the construction time. As a result, it is possible to reduce construction costs and energy consumption by eliminating unnecessary operations.

[0040] 9 and 10 are diagrams illustrating another example of the second sensor possessed by the backhoe 100. In FIG. 8, sensor 52, which is a mechanical sensor, is illustrated as the second sensor. While an example has been shown in which the detection plate of the mechanical sensor moves forward and backward (pushing direction in FIG. 8) when detecting soil / sand 1, indicating the presence of soil / sand 1 in the predetermined area 53, the second sensor may be configured with other types of sensors as long as it can detect whether soil / sand 1 is present in the predetermined area 53. For example, sensor 54 shown in FIG. 9, which is a pressure sensor, may be employed, and the presence of soil / sand 1 in the predetermined area 53 may be detected when the pressure value exceeds a predetermined value. Alternatively, sensor 55 shown in FIG. 10, which is a distance sensor, may be employed, and the presence of soil / sand 1 in the predetermined area 53 may be detected when the distance is less than a predetermined distance or zero.

[0041] The above-described embodiments are illustrative examples provided to facilitate understanding of the invention. The present invention is not limited to the above-described embodiments, and should be understood to encompass various modifications and alternative forms of the above-described embodiments. For example, it will be understood that the above-described embodiments can be embodied by modifying the components without departing from the spirit of the invention. It will also be understood that various embodiments can be implemented by appropriately combining multiple components disclosed in the above-described embodiments. Furthermore, it will be understood by those skilled in the art that various embodiments can be implemented by deleting some components from all of the components shown in the embodiments, or by adding some components to the components shown in the embodiments.

[0042] In the above-described embodiment, the backhoe 100 is given as an example of an excavator, but the excavator may be any excavator having a bucket, and may be, for example, another type of hydraulic shovel such as a front hoe.

[0043] In the above-described embodiment, an example is shown in which the sensor 50 is attached to the bucket 20, but the sensor 50 only needs to be able to detect soil and sand inside the bucket 20, and may be attached to another component of the work arm device 10, such as the arm 30, and is not limited to the bucket 20.

[0044] In the above-described embodiment, an example has been shown in which the sensor 50 includes two sensors (sensor 51 and sensor 52), but the sensor 50 may also be configured as a single sensor that detects the distance to the soil surface. In that case, for example, when the distance detected by the sensor 50 is within a predetermined distance, the control device 60 may transition the operating state of the working arm device 10 from the first operation to the second operation, and when the distance detected by the sensor 50 is another predetermined distance (for example, 0) that is shorter than the predetermined distance, the control device 60 may transition the operating state of the working arm device 10 from the second operation to the third operation.

[0045] In the above-described embodiment, an example has been shown in which the control device 60 of the backhoe 100 performs the above-described control process, that is, the process of determining the transition timing for each operation that constitutes the excavation operation, but this control process does not necessarily have to be performed within the backhoe 100. As shown in FIG. 11 , in a system 200 that is made up of a backhoe 101 and a control device 61 that can communicate via a network NW such as the Internet, the control device 61 may perform the above-described control process and determine the transition timing for each operation in the automated excavation operation, and may control the operation of the working arm device 10 in accordance with the determined transition timing. [Explanation of symbols]

[0046] 1: Earth and sand 10: Working arm device 20: Bucket 21: Tooth 30: Arm 50, 51, 52, 54, 55: Sensors 51p:Position 53: Predetermined area 60, 61: Control device 100, 101: Backhoe

Claims

1. a working arm device having a bucket and excavating an excavation target with the bucket; a sensor attached to the work arm device for detecting the excavation target; a control device for controlling the operation of the working arm device, which determines, based on the detection result of the sensor, a transition timing from a first operation including a vertically downward component for moving the bucket to a second operation including a horizontal component for moving the bucket, and a transition timing from the second operation to a third operation including a vertically upward component for moving the bucket. An excavator characterized by:

2. 2. The excavator according to claim 1, The sensor a first sensor that detects a vertical positional relationship between the bucket and the surface of the excavation target; a second sensor that detects the presence of the excavation target in a predetermined area within the bucket, The control device determining a transition timing from the first operation to the second operation based on a detection result of the first sensor; determining a timing for transition from the second operation to the third operation based on a detection result of the second sensor; An excavator characterized by:

3. 3. The excavator according to claim 2, The work arm device further includes an arm that supports the bucket, The first sensor is disposed on the arm-side edge of the bucket toward the teeth of the bucket and detects the distance to the surface; The control device When the first sensor detects the surface within a predetermined distance, the operation of the work arm device is transitioned from the first operation to the second operation; When the second sensor detects the presence of the excavation target in a region near the edge on the arm side of the position corresponding to the predetermined distance, the operation of the working arm device is shifted from the second operation to the third operation. An excavator characterized by:

4. The excavator according to any one of claims 1 to 3, The sensor is attached to the bucket. An excavator characterized by:

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