Information processing device that estimates amount of soil in bucket of shovel from angles of boom and arm, shovel, method, and program

Abstract

An information processing device (1) comprises: a center-of-gravity position calculation unit (152) that determines respective center-of-gravity positions of a boom of a shovel, an arm attached to one end of the boom, and a bucket attached to a tip of the arm on the basis of a first angle, which is an angle of the boom relative to a horizontal plane, and a second angle, which is an angle of the arm relative to the horizontal plane; a moment calculation unit (153) that finds a gravity moment generated around the rotation center of a boom rotation shaft for rotating the boom by gravity from the respective masses and the respective center-of-gravity positions of the boom, the arm, and the bucket, and finds a pressure moment of the pressure of a boom cylinder for vertically driving the boom; and an amount-of-soil calculation unit (154) that finds the amount of soil in the bucket on the basis of the gravity moment and the pressure moment.

Description

Information processing device, shovel, method and program for estimating the volume of soil in a shovel bucket from the angles of the boom and arm

[0001] The present invention relates to an information processing device, a shovel, a method, and a program for estimating the amount of soil in a shovel bucket from the angles of a boom and an arm.

[0002] Excavators are often used to load soil into dump trucks. To load within the maximum load capacity of a dump truck, the mass of soil to be loaded into the excavator's bucket is calculated and integrated, and the integrated value is adjusted so that it is equal to or less than the maximum load capacity. The mass of the soil is calculated after excavation and while the soil is being lifted. For example, Patent Document 1 discloses a technology for calculating the weight of the load, such as soil and sand, being lifted by the bucket based on the output values ​​of angle sensors attached to the boom, arm, and bucket, and a boom-bottom pressure sensor.

[0003] Japanese Patent Application Laid-Open No. 2022-156425

[0004] The angle sensor attached to the bucket is necessary to determine the center of gravity of the bucket and the load, such as soil and sand. The angle sensor attached to the bucket can also detect bucket movement from the angle output, and can be used, for example, to determine whether the bucket is being unloaded, dropping the load, such as soil, into a dump truck. However, the angle sensor attached to the bucket, along with its attached cable, often comes into contact with soil and sand during excavation. Therefore, the angle sensor attached to the bucket is more likely to be damaged by impact when coming into contact with soil and sand during excavation than other angle sensors attached to the boom, arm, etc.

[0005] The present invention has been made in consideration of the above-mentioned circumstances, and aims to make it possible to determine the mass of soil loaded into a bucket even when an angle sensor is not attached to the bucket.

[0006] In order to achieve the above object, the information processing device of the present invention comprises: a center of gravity position calculation unit that calculates the respective positions of the center of gravity of the boom, the arm, and the bucket attached to the tip of the arm, based on a first angle that is the angle of the boom of the shovel with respect to the horizontal plane and a second angle that is the angle of the arm attached to one end of the boom with respect to the horizontal plane; a moment calculation unit that calculates a gravitational moment generated around the center of rotation of a boom rotation shaft for rotating the boom by gravity from the respective masses and center of gravity positions of the boom, the arm, and the bucket, and a pressure moment of the pressure of a boom cylinder for driving the boom up and down; and an soil volume calculation unit that calculates the volume of soil in the bucket based on the gravitational moment and the pressure moment.

[0007] According to the present invention, the mass of soil loaded in the bucket can be determined even when an angle sensor is not attached to the bucket.

[0008] FIG. 1 is a diagram showing an overview of an excavator according to an embodiment of the present invention. FIG. 2 is a diagram showing the configuration of an information processing system according to an embodiment. FIG. 3 is a diagram showing the hardware configuration of an information processing device according to an embodiment. FIG. 4 is a diagram for explaining the coordinates of the connection parts and center of gravity of the boom, arm, and bucket of the excavator according to an embodiment. FIG. 5 is a diagram for explaining moments of the boom, arm, and bucket of the excavator according to an embodiment. FIG. 6 is a diagram for explaining a method for determining measurement and earth discharge state according to an embodiment.

[0009] The information processing device according to the embodiment of the present invention is a device that can calculate the mass of soil loaded into a bucket based on angles acquired from angle sensors attached to the boom and arm of an excavator and the hydraulic pressure of the boom cylinder. The information processing device, method, and program according to the embodiment will be described in detail below with reference to the drawings.

[0010] 1 shows an overview of an excavator 4 to which an information processing device 1 according to an embodiment of the present invention is attached. The excavator 4 includes a boom 41, a boom cylinder 42, an arm 43, a bucket 44, a cabin 45, a drive unit 46, a base 47, a rotating unit 48, and a caterpillar 49. The boom 41 has an arm connection portion 411 for connecting the arm 43 at one end and a boom rotation shaft 412 connected to the drive unit 46 at the other end. The boom cylinder 42 is a cylinder for moving the boom 41 up and down. One end of the boom cylinder 42 is connected to the center of the boom 41 by a rod-side cylinder connection portion 421, and the other end is connected to the drive unit 46 by a bottom-side cylinder connection portion 422. A boom sensor 21 for measuring the bending angle of the boom 41 is disposed near the rod-side cylinder connection portion 421.

[0011] The boom cylinder 42 is a hydraulic cylinder and includes a first boom hydraulic pressure sensor 23 that measures the hydraulic pressure on the rod side and a second boom hydraulic pressure sensor 24 that measures the hydraulic pressure on the bottom side. The first boom hydraulic pressure sensor 23 is built in near a rod-side cylinder connection portion 421 of the boom cylinder 42. The second boom hydraulic pressure sensor 24 is built in near a bottom-side cylinder connection portion 422 of the boom cylinder 42.

[0012] One end of the arm 43 is connected to an arm connection portion 411 of the boom 41. The arm 43 also has a bucket connection portion 441 at the other end for connecting a bucket 44. An arm sensor 22 for measuring the bending angle of the arm 43 is disposed near the arm connection portion 411 of the boom 41. The boom sensor 21 and the arm sensor 22 can be configured using, for example, an inertial measurement unit (IMU). An inertial measurement unit is a device that can detect three-dimensional inertial motion (translational motion and rotational motion in three orthogonal axial directions) at the location to which it is attached. The boom sensor 21 is an example of a first angle sensor in the claims. The arm sensor 22 is an example of a second angle sensor in the claims.

[0013] The cabin 45 is a location where a user who operates the excavator 4 gets in. In this embodiment, it is assumed that the information processing device 1 is attached to the cabin 45. The drive unit 46 drives various components such as the boom 41, the boom cylinder 42, the rotating unit 48, and the caterpillar 49. The drive unit 46 is connected to a boom rotation shaft 412 of the boom 41 and a bottom-side cylinder connection portion 422 of the boom cylinder 42. As the drive unit 46 moves the boom rotation shaft 412, the boom cylinder 42 moves up and down. This allows the boom 41 to move up and down. Therefore, the center of the boom rotation shaft 412 becomes the rotation center of the boom 41. Furthermore, as the boom cylinder 42 moves up and down, the hydraulic pressure values ​​measured by the first boom hydraulic sensor 23 and the second boom hydraulic sensor 24 change.

[0014] The boom 41, cabin 45, and drive unit 46 are attached to the base 47. The rotating unit 48 can rotate left and right. The rotating unit 48 is connected to the base 47, and by rotating, the positions of the boom 41, cabin 45, etc. attached to the base 47 can be moved left and right. The caterpillar 49 moves the excavator 4.

[0015] The excavator 4 can lift soil F loaded in the bucket 44 by balancing the rotation axis moment Ma generated around the boom rotation axis 412 of the boom 41 and the hydraulic moment Mh generated by the hydraulic pressure of the boom cylinder 42. The rotation axis moment Ma is a moment generated by gravity from the masses and center-of-gravity positions of the boom 41, arm 43, bucket 44, and soil F loaded in the bucket 44. The hydraulic moment Mh is a moment calculated from the differential pressure between the hydraulic pressure at the rod-side cylinder connection portion 421 and the bottom-side cylinder connection portion 422 of the boom cylinder 42. The rotation axis moment Ma is an example of a gravity moment in the claims. The hydraulic moment Mh is an example of a pressure moment in the claims.

[0016] When soil F is loaded into the bucket 44 of the shovel 4 and the bucket 44 is raised to a raised position 44', the value of the rotation axis moment Ma generated around the boom rotation axis 412 of the boom 41 also changes depending on the angle of the boom 41 and the angle of the arm 43.

[0017] Furthermore, when soil F is loaded into the bucket 44 of the shovel 4 and the bucket 44 is raised to a raised position 44', the hydraulic pressure at the rod-side cylinder connection portion 421 of the boom cylinder 42 and the hydraulic pressure at the bottom-side cylinder connection portion 422 change due to the masses of the boom 41, arm 43, bucket 44, and soil F, as well as gravity. When the hydraulic pressure changes, the hydraulic moment Mh also changes. Therefore, in this embodiment, the mass of soil F loaded into the bucket 44 is estimated by utilizing the balance between the rotation axis moment Ma, which changes with the change in the angle of the boom 41 and arm 43, and the hydraulic moment Mh, which changes with the change in the hydraulic pressure of the boom cylinder 42. Hereinafter, the mass of soil F loaded into the bucket 44 will be referred to as the soil volume.

[0018] Fig. 2 shows an overview of an information processing system 100 including an information processing device 1. As shown in Fig. 2, the information processing device 1 includes an operation input unit 11, a communication unit 12, a display unit 13, a storage unit 14, and a control unit 15. The operation input unit 11 accepts various operations from a user. The communication unit 12 transmits and receives various data to and from the outside. The display unit 13 displays data input by the user, data determined by the control unit 15, etc.

[0019] The memory unit 14 stores various programs for determining the amount of soil loaded in the bucket 44, a measurement start threshold 141, and an earth discharge determination threshold 142. The measurement start threshold 141 is a threshold for determining the timing to start measuring the amount of soil. The earth discharge determination threshold 142 is a threshold for determining whether the soil F loaded in the bucket 44 has been loaded onto a dump truck or the like. The measurement start threshold 141 is an example of a first threshold in the claims. The earth discharge determination threshold 142 is an example of a second threshold in the claims.

[0020] The control unit 15 includes a data acquisition unit 151, a center-of-gravity position calculation unit 152, a moment calculation unit 153, a soil volume calculation unit 154, a determination unit 155, and a display control unit 156. The data acquisition unit 151 acquires angle data from a boom sensor 21 attached to the boom 41 and an arm sensor 22 attached to the arm 43. The data acquisition unit 151 also acquires hydraulic pressure data from a first boom hydraulic pressure sensor 23 built in near the rod-side cylinder connection portion 421 of the boom cylinder 42 and a second boom hydraulic pressure sensor 24 built in near the bottom-side cylinder connection portion 422.

[0021] The center of gravity position calculation unit 152 calculates the center of gravity positions of the boom 41, arm 43, and bucket 44 from the angle data acquired from the boom sensor 21 and the arm sensor 22. In this embodiment, it is assumed that the center of gravity position of the soil F coincides with the center of gravity position of the bucket 44. The moment calculation unit 153 calculates the rotation axis moment Ma generated around the rod-side cylinder connection portion 421 of the boom cylinder 42, using the center of gravity positions of the boom 41, arm 43, and bucket 44 calculated by the center of gravity position calculation unit 152. The moment calculation unit 153 also calculates the hydraulic moment Mh due to the hydraulic pressure of the boom cylinder 42, from the hydraulic pressure data acquired from the first boom hydraulic pressure sensor 23 and the second boom hydraulic pressure sensor 24.

[0022] The soil volume calculation unit 154 calculates the volume of soil loaded into the bucket 44 from the rotation axis moment Ma and the hydraulic moment Mh. The determination unit 155 determines the timing for measuring the soil volume. The display control unit 156 displays various data, including a combination of text, graphics, etc., on the display unit 13.

[0023] Each function in the control unit 15 of the information processing device 1 is realized by executing various programs. An example of hardware for executing the various programs is shown in Fig. 3. The information processing device 1 includes a processor 31, a main memory device 32, an auxiliary memory device 33, an input device 34, an operation device 35, a display controller 36, a display device 37, a communication device 38, and a bus 39 that interconnects these elements.

[0024] The processor 31 processes data according to various programs. The processor 31 can be composed of a processing device such as a CPU (Central Processing Unit) or an MPU (Micro-processing Unit). The main storage device 32 functions as a work area for the processor 31. The main storage device 32 can be composed of, for example, a RAM (Random Access Memory). The auxiliary storage device 33 stores various programs executed by the processor 31, fixed data, etc. The auxiliary storage device 33 can store data for a long period of time. The auxiliary storage device 33 functions as the storage unit 14 of the information processing device 1 shown in FIG. 2. The auxiliary storage device 33 can be composed of, for example, a flash memory, an HDD (Hard Disk Drive), an SSD (Solid State Drive), etc.

[0025] The input device 34 accepts various data inputs. For example, the input device 34 accepts data input from the boom sensor 21, the arm sensor 22, the first boom hydraulic sensor 23, and the second boom hydraulic sensor 24 shown in FIG. 2. The operation device 35 accepts various operations from the user. The operation device 35 can be configured with devices such as a keyboard and a touch panel. The operation device 35 functions as the operation input unit 11 of the information processing device 1 shown in FIG. 2.

[0026] The display controller 36 outputs a video signal for displaying display data consisting of characters and images to the display device 37. The display controller 36 can be configured using a video signal output device such as a video card, a GPU (Graphics Processing Unit), or a graphics board. The display device 37 is a display device that functions as the display unit 13 of the information processing device 1 shown in FIG. 2. The display device 37 can be configured using a display interface device such as an LCD (Liquid Crystal Display) or an organic EL (Electro-Luminescence) panel.

[0027] The communication device 38 communicates with other devices and transmits and receives various data. The communication device 38 functions as the communication unit 12 shown in Fig. 2. The communication device 38 can be configured using devices that use various communication methods, such as a wireless local area network (LAN), Bluetooth (registered trademark), or Wi-Fi (registered trademark).

[0028] Next, methods for calculating the rotational shaft moment Ma and hydraulic moment Mh will be described below with reference to Figures 4 and 5. As described above, the rotational shaft moment Ma is a moment generated by gravity from the masses and center-of-gravity positions of the boom 41, arm 43, bucket 44, and soil F loaded into the bucket 44. Also, as described above, the hydraulic moment Mh is a moment calculated from the differential pressure between the hydraulic pressure at the rod-side cylinder connection portion 421 and the bottom-side cylinder connection portion 422 of the boom cylinder 42.

[0029] 4, the center of rotation Po of the boom rotation shaft 412 of the boom 41 is set as the origin, with the horizontal direction being the x direction and the vertical direction being the y direction. Furthermore, the center of rotation of the arm connection part 411 at the end of the boom 41 opposite the boom rotation shaft 412 is set as the center of rotation of the arm 43. The center of rotation of the bucket connection part 441 at the end of the arm 43 opposite the arm connection part 411 is set as the center of rotation of the bucket 44. The center of gravity of the boom 41 is set as Pbm, the center of gravity of the arm 43 is set as Pam, and the center of gravity of the bucket 44 is set as Pbt. Note that the center of gravity of the soil F to be loaded into the bucket 44 is set at the same position as the center of gravity Pbt of the bucket 44.

[0030] Let Lbm be the distance connecting the rotation center Po of the boom rotation shaft 412 and the rotation center of the arm connection part 411. Let Lam be the distance connecting the rotation center of the arm connection part 411 and the rotation center of the bucket connection part 441. Let LHbt be the distance connecting the rotation center of the bucket connection part 441 and the center of gravity Pbt of the bucket 44. Let Pcy be the center position of the bottom side cylinder connection part 422 of the boom cylinder 42. Let Lcy be the distance connecting the center position Pcy of the bottom side cylinder connection part 422 and the rotation center Po of the boom rotation shaft 412.

[0031] Let θbm be the angle of the Lbm direction with respect to the horizontal plane. Let θam be the angle of the Lam direction with respect to the horizontal plane. θbm is calculated based on the angle measured by the boom sensor 21 shown in FIG. 4. Let θbt be the angle of the LHbt direction with respect to the horizontal plane. In this embodiment, θbt is a fixed value because the bucket 44 is fixed in the lifting posture 44' shown in FIG. 1. Let θcy be the angle of the Lcy direction with respect to the horizontal plane. Since θcy is determined by the structure of the shovel 4, it is a fixed value.

[0032] Let LHbm be the distance between the intersection of the center of gravity Pbm of the boom 41 and the perpendicular to Lbm, and the rotation center Po of the boom rotation shaft 412. Let LVbm be the distance between the center of gravity Pbm of the boom 41 and the intersection of the perpendicular to Lbm. Let θam be the angle of the Lam direction with respect to the horizontal plane. θam is the pitch angle at the center of the arm connection part 411 measured by the arm sensor 22 attached to the arm 43. Note that θbm is an example of the first angle in the claims. Also, θam is an example of the second angle in the claims.

[0033] Let LHam be the distance between the intersection of the center of gravity of the arm 43 with the perpendicular line from Pam to Lam and the center of rotation of the arm connection part 411. Let LVam be the distance from the center of gravity Pam of the arm 43 to the intersection of the perpendicular line to Lam. Let LHbt be the distance connecting the center of rotation of the bucket connection part 441 and the center of gravity Pbt of the bucket 44.

[0034] In this case, the coordinates (xPbm, yPbm) of the center of gravity Pbm of the boom 41 can be expressed by the following equations (1) and (2): xPbm=LHbm·cos θbm−LVbm·sin θbm (1) yPbm=LHbm·sin θbm+LVbm·cos θbm (2)

[0035] The coordinates (xPam, yPam) of the center of gravity Pam of the arm 43 can be expressed by the following equations (3) and (4): xPam=Lbm·cos θbm+LHam·cos θam+LVam·sin θam (3) yPam=Lbm·sin θbm−LHam·sin θam+LVam·cos θam (4)

[0036] The coordinates (xPbt, yPbt) of the center of gravity Pbt of the bucket 44 can be expressed by the following equations (5) and (6): xPbt=Lbm·cos θbm+Lam·cos θam+LHbt·cos θbt (5) yPbt=Lbm·sin θbm-Lam·sin θam-LHbt·sin θbt (6)

[0037] Furthermore, the coordinates (xPcy, yPcy) of the center position Pcy of the bottom-side cylinder connection portion 422 of the boom cylinder 42 can be expressed by the following equations (7) and (8). xPcy=Lcy·cos θcy (7) yPcy=Lcy·sin θcy (8)

[0038] Here, as shown in FIG. 5 , Fbm is the gravity force relative to the boom 41. Fbm' is the component of Fbm in a direction perpendicular to the direction of the rotation center Po of the boom rotation shaft 412 of the boom 41. Fam is the gravity force relative to the arm 43. Furthermore, Fam' is the component of Fam in a direction perpendicular to the direction of the rotation center Po of the boom rotation shaft 412 of the boom 41. Fbt is the gravity force relative to the bucket 44. Furthermore, Fbt' is the component of Fbt in a direction perpendicular to the direction of the rotation center Po of the boom rotation shaft 412 of the boom 41. Fsl is the gravity force relative to the soil F. Furthermore, Fsl' is the component of Fsl in a direction perpendicular to the direction of the rotation center Po of the boom rotation shaft 412 of the boom 41.

[0039] Let Fcy be the differential pressure between both ends of the boom cylinder 42. Let Fcy' be the component of Fcy in a direction perpendicular to the direction of the rotation center Po of the boom rotation shaft 412 of the boom 41. Here, let FTcy be the hydraulic pressure on the rod side cylinder connection portion 421 side of the boom cylinder 42 obtained from the first boom hydraulic pressure sensor 23 shown in FIG. 1. Let FBcy be the hydraulic pressure on the bottom side cylinder connection portion 422 side of the boom cylinder 42 obtained from the second boom hydraulic pressure sensor 24 shown in FIG. 1. In this case, Fcy can be expressed by the following equation (9). Fcy = |FTcy - FBcy| (9)

[0040] Based on the coordinates calculated by the above equations (1) to (9) and the differential pressure of the boom cylinder 42, an equation for balancing the rotation axis moment Ma generated around the rotation center Po of the boom rotation axis 412 of the boom 41 and the hydraulic moment Mh calculated from the differential pressure at both ends of the boom cylinder 42 is created. First, the rotation axis moment Ma is the sum of the moments due to gravity of the boom 41, arm 43, bucket 44, and soil F. Here, Mbm is the moment due to gravity of the boom 41. Mam is the moment due to gravity of the arm 43. Mbt is the moment due to gravity of the bucket 44. Msl is the moment due to gravity of the soil F.

[0041] In this case, the moment Mbm due to gravity of the boom 41 can be expressed by the following equation (10): Mbm=Fbm′·|PoPbm|=Fbm·|xPbm| (10)

[0042] The moment Mam of the arm 43 due to gravity can be expressed by the following equation (11): Mam=Fam'·|PoPam|=Fam·|xPam| (11)

[0043] The moment Mbt due to gravity of the bucket 44 can be expressed by the following equation (12): Mbt=Fbt′·|PoPbt|=Fbt·|xPbt| (12)

[0044] The moment Msl due to the gravity of the soil F can be expressed by the following equation (13). As described above, the center of gravity of the soil F is assumed to be at the same position as the center of gravity Pbt of the bucket 44. Msl=Fsl'·|PoPbt|=Fsl·|xPbt| (13)

[0045] From the above, the rotation axis moment Ma can be expressed by the following equation (14): Ma=Mbm+Mam+Mbt+Msl (14)

[0046] Further, the hydraulic moment Mh calculated from the differential pressure between both ends of the boom cylinder 42 can be expressed by the following equation (15): Mh=Fcy'·|PoPcy|=Fcy·|xPcy| (15)

[0047] The balance between the rotation shaft moment Ma and the hydraulic moment Mh can be expressed by the following equation (16): Ma=Mh=Mbm+Mam+Mbt+Msl (16)

[0048] From equation (16), the gravity of soil F can be expressed by the following equation (17): Fsl = (Fcy xPcy - Fbm xPbm - Fam xPam - Fbt xPbt) / Pbt (17) The gravity Fsl of soil F is expressed as gravity 9.8 [m / s ２ ]The volume of soil can be calculated by dividing by

[0049] In the calculation of the soil volume shown in equations (1) to (17), the angle θbt of the bucket 44 is a fixed value because it is the angle of the lifting posture 44'. For example, the posture of the bucket 44 differs from the lifting posture 44' before, during, and during the excavation of soil F. In this case, the soil volume value calculated before excavation, etc., differs from the value calculated in the lifting posture 44', resulting in a large error. Normally, when the excavator 4 loads soil F into a dump truck, the excavator 4 loads the bucket 44 with soil F, lifts it up, and then swings the boom 41, arm 43, and bucket 44 to the dump truck bed while maintaining the lifting posture 44'. During the swing, the posture of the bucket 44 does not change from the lifting posture 44', so the calculated soil volume value has little error. Therefore, in this embodiment, the average soil volume calculated during the swing is used as the soil volume of soil F loaded into the bucket 44.

[0050] The timing of calculating the soil volume will be explained with reference to Fig. 6. The graph shown in Fig. 6 shows the calculated soil volume values ​​on the vertical axis and time (t) on the horizontal axis, and shows the calculated soil volume values ​​in chronological order. In the graph, the soil volume calculated using the above-mentioned equations (1) to (17) is shown by a solid line, and the true soil volume is shown by a dotted line.

[0051] After excavation, when the bucket 44 is raised in the lifting position 44', a lift force, which is a force in a direction opposite to gravity, is applied to the bucket 44. If the lift force is greater than the gravity acting on the bucket 44 and the soil F, the bucket 44 can be lifted. In this case, the gravity acting on the bucket 44 and the soil F takes a negative value, and therefore the volume of soil calculated using the above-mentioned equations (1) to (17) takes a negative value.

[0052] As the position of the bucket 44 approaches the specified height for swinging, the lifting force gradually decreases, and the gravity on the bucket 44 and soil F changes from a negative value to a positive value. As a result, the calculated volume of soil also changes from a negative value to a positive value. After that, when the position of the bucket 44 reaches the specified height for swinging, the excavator 4 swings the bucket 44 up to the bed of the dump truck. During the swing, the attitude of the bucket 44 does not change from the lifted attitude 44', so the calculated volume of soil remains a roughly constant value. Then, when the excavator 4 unloads the soil F onto the bed of the dump truck, the amount of soil F on the bucket 44 decreases, and so the volume of soil also decreases.

[0053] In this embodiment, the section in Figure 6 where the calculated soil volume exceeds the measurement start threshold indicated by the dashed line and becomes a constant value is considered to be the section in which the bucket 44 is swinging, and the average value of this section is considered to be the soil volume. Furthermore, if, after swinging, the soil volume calculated by earth discharge falls below the earth discharge determination threshold indicated by the dashed-dot line, it is determined that earth has been discharged, and the soil volume determined during swinging is considered to have been loaded onto the dump truck. The measurement start threshold is stored in the memory unit 14 shown in Figure 2 as a measurement start threshold 141, and the earth discharge determination threshold is stored in the memory unit 14 as an earth discharge determination threshold 142.

[0054] A user who loads soil F into a dump truck with a shovel 4 can estimate the volume of soil in the bucket 44 during work by executing a soil volume estimation processing program stored in the storage unit 14 of the information processing device 1 shown in Fig. 2. The soil volume estimation processing program is linked to, for example, an icon displayed on the screen of the display unit 13 of the information processing device 1 shown in Fig. 2, and is started when the user selects the icon via the operation input unit 11. The processing flow of the soil volume estimation processing program will be described below with reference to the flowchart of soil volume estimation processing shown in Fig. 8.

[0055] The data acquisition unit 151 included in the control unit 15 of the information processing device 1 shown in Fig. 2 initializes the total soil volume and counter N (step S101). The data acquisition unit 151 of the control unit 15 acquires various data (step S102). Specifically, the data acquisition unit 151 acquires the measurement start threshold 141 and the soil discharge determination threshold 142 from the memory unit 14 of the information processing device 1 shown in Fig. 2. The data acquisition unit 151 also acquires each value of Lbm, Lam, etc. of the shovel 4 shown in Fig. 4 from the memory unit 14.

[0056] The center of gravity position calculation unit 152 included in the control unit 15 of the information processing device 1 shown in Fig. 2 executes soil volume calculation processing (step S103). The soil volume calculation processing will be described below with reference to the flowchart shown in Fig. 8.

[0057] The center-of-gravity position calculation unit 152 acquires the angles of the boom 41, the arm 43, and the bucket 44 (step S201). Specifically, the center-of-gravity position calculation unit 152 calculates the angle θbm of the boom 41 based on the angle measured by the boom sensor 21 shown in FIG. 1. The center-of-gravity position calculation unit 152 acquires the angle θa of the arm 43 from the arm sensor 22 shown in FIG. 1. The center-of-gravity position calculation unit 152 acquires the angle θbt of the bucket 44, which is a fixed value, from the storage unit 14.

[0058] The center-of-gravity position calculation unit 152 calculates the coordinates of each part (step S202). Specifically, the center-of-gravity position calculation unit 152 calculates the coordinates of the centers of gravity of the boom 41, the arm 43, and the bucket 44 using the above-mentioned equations (1) to (6). The center-of-gravity position calculation unit 152 also calculates the coordinates of the center position Pcy of the bottom-side cylinder connection portion 422 of the boom cylinder 42 using the above-mentioned equations (7) and (8).

[0059] The moment calculation unit 153 included in the control unit 15 of the information processing device 1 shown in Fig. 2 calculates the rotational shaft moment Ma and the hydraulic moment Mh (step S203). Specifically, the moment calculation unit 153 calculates the rotational shaft moment Ma using the above-mentioned equations (10) to (14). The moment calculation unit 153 also calculates the hydraulic moment Mh using the above-mentioned equations (9) and (15).

[0060] The soil volume calculation unit 154 included in the control unit 15 of the information processing device 1 shown in Fig. 2 calculates the gravity of soil F (step S204). Specifically, the soil volume calculation unit 154 calculates the gravity of soil F using the above-mentioned formulas (16) and (17). The soil volume calculation unit 154 calculates the soil volume (step S205). Specifically, the soil volume calculation unit 154 calculates the gravity of soil F calculated in step S204 as a gravity of 9.8 [m / s ２ The soil volume calculation unit 154 then finishes the soil volume calculation process.

[0061] Now, let's return to FIG. 7. The determination unit 155 included in the control unit 15 of the information processing device 1 shown in FIG. 2 determines whether the soil volume value calculated in step S103 is greater than the measurement start threshold (step S104). If the soil volume value is greater than the measurement start threshold (step S104; YES), the determination unit 155 determines whether the difference between the soil volume calculated last time and this time is less than a predetermined threshold (step S105). Here, as shown in FIG. 6, the calculated soil volume value is constant during rotation. Therefore, the difference between the soil volume calculated last time and this time is small, and the difference value is smaller than the predetermined threshold. Furthermore, when not rotating, the calculated soil volume value is not constant. Therefore, the difference between the soil volume calculated last time and this time is large, and the difference value is greater than the predetermined threshold.

[0062] If the difference is not less than the predetermined threshold (step S105; NO), the determination unit 155 returns to step S103. If the difference is less than the predetermined threshold (step S105; YES), the determination unit 155 adds the soil volume calculated this time to the total soil volume (step S106). The determination unit 155 adds 1 to the counter (step S107). The determination unit 155 returns to step S103.

[0063] If the soil volume value is not greater than the measurement start threshold value in step S104 (step S104; NO), the determination unit 155 determines whether the previously calculated soil volume value is greater than the currently calculated soil volume value (step S108). If the previously calculated soil volume value is not greater than the currently calculated soil volume value (step S108; NO), the determination unit 155 returns to step S103. If the previously calculated soil volume value is greater than the currently calculated soil volume value (step S108; YES), the determination unit 155 determines whether the currently calculated soil volume value is less than the soil discharge measurement threshold value (step S109).

[0064] If the value of the soil volume calculated this time is not smaller than the soil discharge measurement threshold (step S109; NO), the determination unit 155 returns to step S103. On the other hand, if the value of the soil volume calculated this time is smaller than the soil discharge measurement threshold (step S109; YES), the soil volume calculation unit 154 of the control unit 15 shown in Fig. 2 calculates the average soil volume (step S110). Specifically, the soil volume calculation unit 154 divides the total soil volume value by the counter value.

[0065] The soil volume calculation unit 154 clears the total soil volume and the counter (step S111). The determination unit 155 of the control unit 15 determines whether or not an instruction to end the process has been received from the worker (step S112). For example, if the user inputs an instruction to end the process from the operation input unit 11 of the information processing device 1 shown in FIG. 2, the soil volume estimation process ends. If the user does not input an instruction to end the process from the operation input unit 11, the soil volume estimation process continues.

[0066] If the operator does not issue an instruction to end the process (step S112; NO), the determination unit 155 returns to step S103. If the operator issues an instruction to end the process (step S112; YES), the determination unit 155 ends the soil volume estimation process.

[0067] As described above, the information processing device 1 according to this embodiment can estimate the mass of soil F loaded into the bucket 44 by utilizing the balance between the rotation axis moment Ma, which changes with the change in the angle of the boom 41 and arm 43, and the hydraulic moment Mh, which changes with the change in the hydraulic pressure of the boom cylinder 42. This makes it possible to determine the mass of soil loaded into the bucket even when an angle sensor is not attached to the bucket.

[0068] Furthermore, the present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the gist of the present invention.

[0069] In the above embodiment, as shown in Fig. 1 , the information processing device 1 is arranged inside the cabin 45 of the shovel 4. However, the present invention is not limited to this, and the information processing device 1 may be arranged outside the cabin 45 as a separate unit.

[0070] In the above embodiment, the bucket 44 of the shovel 4 is configured as one bucket 44 shown in FIG. 1 . However, the present invention is not limited to this, and a clamshell bucket 44A formed by combining two buckets 44 may also be used. In the clamshell bucket 44A, when lifting soil F, the bucket 44A is closed and suspended. In this case, by setting θbt = 90°, the volume of soil can be calculated using equations (1) to (17) described above in the embodiment.

[0071] Furthermore, in the above embodiment, the hydraulic pressure on the rod-side cylinder connection portion 421 side of the boom cylinder 42 is measured by the first boom hydraulic pressure sensor 23, the hydraulic pressure on the bottom-side cylinder connection portion 422 side of the boom cylinder 42 is measured by the second boom hydraulic pressure sensor 24, and the differential pressure of the measured hydraulic pressures is calculated using equation (9). However, this is not limiting, and a hydraulic pressure sensor may be provided that outputs the differential pressure of the hydraulic pressures measured by the first boom hydraulic pressure sensor 23 and the second boom hydraulic pressure sensor 24 as the hydraulic pressure of the boom cylinder 42. Note that this hydraulic pressure sensor, or the first boom hydraulic pressure sensor 23 and the second boom hydraulic pressure sensor 24 are examples of pressure sensors in the claims.

[0072] Furthermore, in the above embodiments, the "angle with a horizontal plane" may be replaced with an angle with a line or plane in a predetermined direction, such as an "angle with a vertical line."

[0073] Furthermore, a computer capable of realizing each of the above-described functions may be configured by storing and distributing a program for realizing each of the above-described functions on a computer-readable recording medium such as a CD-ROM (Compact Disc Read Only Memory) or a DVD-ROM (Digital Versatile Disc Read Only Memory), and installing the program on the computer. If each function is realized by sharing the work between an OS (Operating System) and an application, or by cooperation between the OS and the application, only the application may be stored on the recording medium.

[0074] The present invention allows various embodiments and modifications without departing from the broad spirit and scope of the present invention. Furthermore, the above-described embodiments are intended to illustrate the present invention and do not limit the scope of the present invention. In other words, the scope of the present invention is defined by the claims, not the embodiments. Various modifications made within the scope of the claims and within the meaning of the disclosure equivalent thereto are considered to be within the scope of the present invention.

[0075] The present invention can be suitably used in an information processing device, a shovel, and an information processing system including the information processing device.

[0076] 1 Information processing device, 4 Excavator, 11 Operation input unit, 12 Communication unit, 13 Display unit, 14 Memory unit, 15 Control unit, 21 Boom sensor, 22 Arm sensor, 23 First boom hydraulic sensor, 24 Second boom hydraulic sensor, 31 Processor, 32 Main memory device, 33 Auxiliary memory device, 34 Input device, 35 Operation device, 36 Display controller, 37 Display device, 38 Communication device, 39 Bus, 41 Boom, 42 Boom cylinder, 43 Arm, 44, 44A Bucket, 44' Lifting position, 45 Cabin, 46 Drive unit, 47 Base, 48 Rotating unit, 49 Caterpillar, 100 Information processing system, 151 Data acquisition unit, 152 Center of gravity position calculation unit, 153 Moment calculation unit, 154 Soil volume calculation unit, 155 Determination unit, 156 Display control unit, 411 Arm connection portion, 412 boom rotation shaft, 421 rod side cylinder connection portion, 422 bottom side cylinder connection portion, 441 bucket connection portion.

Claims

1. a center-of-gravity position calculation unit that calculates the positions of the centers of gravity of the boom, the arm, and a bucket attached to a tip of the arm based on a first angle that is an angle of a boom of a shovel with respect to a horizontal plane and a second angle that is an angle of an arm attached to one end of the boom with respect to the horizontal plane; a moment calculation unit which calculates a gravity moment generated around a rotation center of a boom rotation shaft for rotating the boom by gravity from the masses and center-of-gravity positions of the boom, the arm, and the bucket, and a pressure moment of a pressure of a boom cylinder for driving the boom up and down; a soil volume calculation unit that calculates the soil volume in the bucket based on the gravity moment and the pressure moment; Equipped with The soil volume calculation unit calculates the volume of soil loaded by the shovel based on the value of the soil volume from when the value of the calculated soil volume exceeds a predetermined first threshold value until the value of the calculated soil volume becomes smaller than a predetermined second threshold value. Information processing device.

2. Further, a determination unit is provided that determines to start measuring the amount of soil in the bucket when the value of the amount of soil in the bucket calculated by the soil amount calculation unit is greater than the first threshold value. The information processing device according to claim 1 .

3. The determination unit determines that the amount of soil in the bucket has been discharged when the value of the amount of soil in the bucket calculated by the soil amount calculation unit is less than the second threshold value. The information processing device according to claim 2 .

4. a first angle sensor provided on the boom for measuring the first angle; a second angle sensor provided on the arm for measuring the second angle; a pressure sensor provided in the boom cylinder for measuring a pressure of the boom cylinder, The information processing device according to claim 1 .

5. the first angle sensor and the second angle sensor are inertial measurement devices that detect three-dimensional inertial motion at a location where the first angle sensor and the second angle sensor are attached; the pressure sensor is a hydraulic sensor that outputs, as hydraulic pressure of the boom cylinder, a differential pressure between a hydraulic pressure measured by a first boom hydraulic sensor arranged on the rod side of the boom cylinder and a hydraulic pressure measured by a second boom hydraulic sensor arranged on the bottom side of the boom cylinder; The information processing device according to claim 4.

6. The soil quantity calculation unit determines the quantity of soil loaded by the shovel based on the average value of the soil quantity in the bucket during the period from when the obtained value of the soil quantity in the bucket exceeds the first threshold value until it becomes smaller than the second threshold value. The information processing apparatus according to any one of claims 1 to 3.

7. A boom, A first angle sensor fixed to the boom and measuring a first angle with respect to the horizontal plane, An arm rotatably supported at one end of the boom, A second angle sensor fixed to the arm and measuring a second angle with respect to the horizontal plane, A pressure sensor fixed to a boom cylinder for driving the boom up and down and measuring the pressure of the boom cylinder, A bucket rotatably supported at the tip of the arm, A shovel comprising: By inputting the measured first angle, second angle, and the pressure of the boom cylinder to an information processing apparatus, the information processing apparatus estimates the soil quantity in the bucket, and based on the estimated value of the soil quantity during the period from when the estimated value of the soil quantity exceeds a predetermined first threshold value until it becomes smaller than a predetermined second threshold value, estimates the quantity of soil loaded by the shovel. Shovel.

8. A method executed by an information processing apparatus, Based on a first angle that is the angle of the boom of the shovel with respect to the horizontal plane and a second angle that is the angle of the arm attached to one end of the boom with respect to the horizontal plane, determine the respective center-of-gravity positions of the boom, the arm, and the bucket attached to the tip of the arm, Determine the gravitational moment generated around the center of rotation of the boom rotation axis for rotating the boom by gravity from the respective masses and center-of-gravity positions of the boom, the arm, and the bucket, and the pressure moment of the pressure of the boom cylinder for driving the boom up and down, Based on the gravitational moment and the pressure moment, determine the soil quantity in the bucket, and based on the value of the soil quantity during the period from when the obtained value of the soil quantity exceeds a predetermined first threshold value until it becomes smaller than a predetermined second threshold value, determine the quantity of soil loaded by the shovel. Method.

9. On a computer, A process of obtaining the center-of-gravity positions of each of the boom, the arm, and the bucket attached to the tip of the arm based on a first angle that is the angle of the boom of the excavator with respect to the horizontal plane and a second angle that is the angle of the arm attached to one end of the boom with respect to the horizontal plane. A process of obtaining a gravitational moment generated around the center of rotation of the boom rotation axis for rotating the boom by gravity from the mass and center-of-gravity position of each of the boom, the arm, and the bucket, and a pressure moment of the pressure of the boom cylinder for driving the boom up and down. A process of obtaining the amount of soil in the bucket based on the gravitational moment and the pressure moment, and obtaining the amount of soil loaded by the excavator based on the value of the amount of soil during the period from when the value of the obtained amount of soil exceeds a predetermined first threshold until it becomes smaller than a predetermined second threshold. A program for causing the above to be executed.