JP2023148988A - System and method for estimating weight of load in specially-equipped vehicle and computer program - Google Patents

Abstract

To provide a system and a method for estimating the weight of the load in a specially-equipped vehicle and a computer program.SOLUTION: A specially-equipped vehicle having a hydraulic actuator for lifting a cargo box includes: a first acquisition unit for acquiring first data on the magnitude of a hydraulic pressure from a pressure meter for measuring the magnitude of a hydraulic pressure that acts on the hydraulic actuator; a second acquisition unit for acquiring second data on the magnitude of an inclination angle from an inclination meter for measuring an inclination angle of the specially-equipped vehicle; a storage unit for storing more than one relation between the inclination angle and the magnitude of the hydraulic pressure when the weight and the position of a loaded material are changed, in relation to the weight of the loaded material; and an estimation unit for estimating the weight of the load in the cargo box with reference to the relation stored in the storage unit when the first data and the second data are acquired.SELECTED DRAWING: Figure 4

Description

The present invention relates to a system for estimating the loaded weight of a specially equipped vehicle, a method for estimating the loaded weight of a specially equipped vehicle, and a computer program.

BACKGROUND ART In recent years, large vehicles such as trucks have been known to be equipped with a weight scale for measuring their own weight (loaded weight).

Conventional weight meters use load sensors attached to both ends of the front and rear axles to measure the load on each front, rear, left, and right tire, and calculate the loaded weight from the sum of the outputs of each load sensor.

Japanese Patent Application Publication No. 2004-132871

However, conventional weight meters convert the sum of the outputs of each load sensor into the loaded weight, so when the vehicle is on a slope or the load on the platform is not evenly balanced, etc. It may not be possible to measure the correct loaded weight.

An object of the present invention is to provide a system for estimating the loaded weight of a specially equipped vehicle, a method for estimating the loaded weight of a specially equipped vehicle, and a computer program that can accurately estimate the loaded weight even when the balance of the loaded cargo on the loading platform is uneven. do.

A system for estimating the loaded weight of a specially equipped vehicle according to one aspect of the present invention, with respect to a specially equipped vehicle equipped with a hydraulic actuator for raising and lowering a cargo box, calculates the magnitude of the hydraulic pressure from a pressure gauge that measures the magnitude of the hydraulic pressure acting on the hydraulic actuator. a first acquisition section that acquires first data regarding the tilt angle of the specially equipped vehicle; a second acquisition section that acquires second data regarding the tilt angle from an inclinometer that measures the tilt angle of the specially equipped vehicle; a storage unit that stores a plurality of relationships between the angle of inclination and the magnitude of the oil pressure when changed in association with the weight of the loaded object; and when the first data and the second data are acquired; and an estimation section that estimates the loaded weight in the cargo box by referring to the relationship stored in the storage section.

A method for estimating the loaded weight of a specially equipped vehicle according to one aspect of the present invention is, for a specially equipped vehicle equipped with a hydraulic actuator for raising and lowering a cargo box, calculating the magnitude of the hydraulic pressure from a pressure gauge that measures the magnitude of the hydraulic pressure acting on the hydraulic actuator. If the first data regarding the tilt angle is acquired from the inclinometer that measures the tilt angle of the specially equipped vehicle, and the first data and the second data are acquired, the weight of the loaded object is determined. and estimating the loaded weight in the cargo box with reference to a storage unit that stores a plurality of relationships between the angle of inclination and the magnitude of the hydraulic pressure when the loading position is changed in association with the weight of the loaded object. The computer executes the process.

A computer program according to one aspect of the present invention is configured to cause a computer to determine, with respect to a specially equipped vehicle equipped with a hydraulic actuator for raising and lowering a cargo box, the magnitude of the hydraulic pressure from a pressure gauge that measures the magnitude of the hydraulic pressure acting on the hydraulic actuator. and second data regarding the inclination angle from an inclinometer that measures the inclination angle of the specially equipped vehicle. When the first data and the second data are obtained, the weight and the weight of the loaded object are obtained. Estimating the loaded weight in the cargo box with reference to a storage unit that stores a plurality of relationships between the inclination angle and the magnitude of the hydraulic pressure when the loading position is changed in association with the weight of the loaded object. It is a computer program for executing processing.

According to the present application, even if the balance of the cargo on the platform is not equal, the loaded weight can be estimated with high accuracy.

1 is a side view showing the overall configuration of a specially equipped vehicle according to Embodiment 1. FIG. 1 is a plan view showing the overall configuration of a specially equipped vehicle according to Embodiment 1. FIG. FIG. 3 is a side view of the cargo box in an upright state. FIG. 1 is a block diagram illustrating the configuration of a loaded weight estimation system. It is a graph showing the relationship between the center of gravity position of a cargo box containing a loaded object and a change in pitch angle. It is a graph showing the relationship between oil pressure value and pitch angle when the loaded weight and loading position are changed. FIG. 3 is a conceptual diagram showing an example of a relational table. FIG. 2 is an explanatory diagram illustrating a method for estimating a loaded weight in the first embodiment. 2 is a flowchart illustrating a procedure for estimating a loaded weight in the first embodiment. FIG. 3 is a schematic diagram showing an example of display of loaded weight. FIG. 7 is an explanatory diagram illustrating a method for estimating a loaded weight in Embodiment 2. FIG. FIG. 7 is a block diagram illustrating the configuration of a loaded weight estimation system in Embodiment 3. FIG. 12 is a flowchart illustrating a procedure for estimating a loaded weight in Embodiment 3. FIG. 7 is a block diagram illustrating the configuration of a loaded weight estimation system in Embodiment 4. FIG. 12 is a flowchart illustrating a procedure for estimating a loaded weight in Embodiment 4. FIG. 7 is a block diagram illustrating the configuration of a loaded weight estimation system in Embodiment 5. FIG. 12 is a flowchart illustrating a procedure for estimating a loaded weight in Embodiment 5. FIG. 2 is a schematic diagram showing a configuration example of a learning model.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below based on drawings showing embodiments thereof.
(Embodiment 1)
FIG. 1 is a side view showing the overall configuration of a specially equipped vehicle 1 according to Embodiment 1, FIG. 2 is a plan view thereof, and FIG. 3 is a side view showing a state in which a cargo box is erected. The specially equipped vehicle 1 illustrated in FIGS. 1 to 3 is a dump truck that includes a truck chassis 2, which is a running section, and a dump device 3, which is an example of a mounting device mounted on the running section. In the following description, the front and rear, left and right, and up and down directions refer to the front and back, left and right, and up and down directions as seen from the driver sitting in the driver's seat of the truck chassis 2. Note that FIG. 2 shows a state in which the dump device 3 is removed for the sake of explanation.

The truck chassis 2 includes a cab 20 in which a driver's seat is provided, and a chassis frame 21 that supports the cab 20. The chassis frame 21 is composed of a pair of left and right main frames (vertical joists) 21A, 21A extending in the front-rear direction, and a plurality of cross members (horizontal joists) 21B, ..., 21B that connect the pair of left and right main frames 21A, 21A. (See Figure 2). Front wheels 22F and rear wheels 22R, 22R of the truck chassis 2 are rotatably attached to main frames 21A, 21A via a suspension device (not shown). The truck chassis 2 includes an engine 70 (prime mover) and a transmission connected to the engine 70 via a clutch, and transmits the driving force of the engine 70 to the drive system of the drive wheels (for example, the front wheels 22F). The vehicle is configured to travel by transmitting information via the .

The dump device 3 includes a subframe 30 fixed on the chassis frame 21, and a cargo box 4 supported by the subframe 30 and loaded with a load such as earth and sand. The cargo box 4 is rotatably supported at the rear end of the subframe 30 around a hinge shaft 31 extending in the left-right direction. The packing box 4 is a box with an open top, and includes a front panel 41 arranged to surround a rectangular bottom 40, a pair of left and right side panels 42, and a rear panel (rear tilt) 43. The rear panel 43 is configured to be openable and closable.

The dump device 3 includes a hoist mechanism 5 for tilting the cargo box 4. The hoist mechanism 5 includes, for example, a lift arm 51, a hydraulic cylinder 52, and a tension link 53. When the hydraulic cylinder 52 of the hoist mechanism 5 is extended, the front part of the cargo box 4 is lifted and the cargo box 4 is rotated in a direction in which the angle of inclination becomes larger. In this embodiment, the rotation of the packing box 4 in the direction in which the inclination angle increases is also referred to as the lifting of the packing box 4. On the other hand, when the hydraulic cylinder 52 of the hoist mechanism 5 is shortened, the front part of the cargo box 4 is lowered, and the cargo box 4 rotates in a direction where the inclination angle becomes smaller. In this embodiment, the rotation of the cargo box 4 in the direction in which the inclination angle becomes smaller is also referred to as the lowering of the cargo box 4.

The hydraulic mechanism that expands and contracts the hydraulic cylinder 52 includes a hydraulic pump 61, a hydraulic oil tank 62, a control valve 63, and the like. The hydraulic pump 61, which is a hydraulic pressure supply source, is driven by the power of the engine 70 transmitted via a PTO 71 (Power Take-Off) to pump up and discharge hydraulic oil in a hydraulic oil tank 62 through a hydraulic piping 64. Hydraulic oil (pressure oil) is supplied to the hydraulic cylinder 52 through a main pipe 65 connected to the outlet. Note that power transmission from the engine 70 is switched on and off by a PTO switch 72 provided inside the cab 20.

The supply direction of hydraulic oil discharged from the hydraulic pump 61 is switched by a control valve 63 operated by a manual operation lever 67. For example, when the control valve 63 is in the neutral position by operating the operating lever 67, hydraulic oil is not supplied from the hydraulic pump 61 to the hydraulic cylinder 52, and the cargo box 4 is not tilted. When the operating lever 67 is operated to the raised position, the control valve 63 is switched, and hydraulic oil (pressure oil) is supplied from the hydraulic pump 61 to the hydraulic cylinder 52. The hydraulic cylinder 52 expands when hydraulic oil is supplied, and raises the cargo box 4 . On the other hand, when the operating lever 67 is operated to the lowered position, the control valve 63 is switched, and the hydraulic oil supplied to the hydraulic cylinder 52 is returned to the hydraulic oil tank 62. Accordingly, the hydraulic cylinder 52 is shortened and the cargo box 4 is lowered.

The hydraulic mechanism is provided with a pressure gauge 81 for measuring the magnitude of the hydraulic pressure acting on the hydraulic cylinder 52. The specially equipped vehicle 1 is also provided with an inclinometer 82 for measuring the inclination (pitch and roll) of the truck chassis 2 and an inclinometer 83 for measuring the inclination (pitch and roll) of the cargo box 4. .

The pressure gauge 81 measures the cylinder pressure (hydraulic pressure) of the hydraulic cylinder 52 in time series, and outputs measurement data related to the measured cylinder pressure. The inclinometer 82 is attached to an appropriate location on the chassis frame 21 (for example, near the center in the front-rear direction and the left-right direction). The inclinometer 82 measures the longitudinal inclination (pitch) and the lateral inclination (roll) of the truck chassis 2 with respect to the direction of gravity (vertical direction) in time series, and provides measurement data related to the measured inclination. Output. The data regarding the inclination angle of the truck chassis 2 obtained by the inclinometer 82 can be considered as data on the inclination angle of the entire vehicle, that is, the specially equipped vehicle 1. The inclinometer 83 is attached to an appropriate location of the packing box 4, and measures the longitudinal direction (pitch) and the horizontal direction (roll) of the packing box 4 based on the direction of gravity (vertical direction) in chronological order. Output measurement data related to the measured slope. By taking the difference between the measured value of the inclinometer 83 and the measured value of the inclinometer 82, the dump angle of the cargo box 4 with respect to the truck chassis 2 is calculated.

The specially equipped vehicle 1 includes an estimation device 100 that estimates the weight of a loaded object (loaded weight) based on data obtained by a pressure gauge 81 and an inclinometer 82. In the present embodiment, the loaded weight represents the weight of the load loaded in the cargo box 4, including the passengers riding in the specially equipped vehicle 1, the fuel loaded in the specially equipped vehicle 1, and the traveling parts constituting the specially equipped vehicle 1. The weight of bodywork equipment, etc. shall not be included. It is assumed that the weight of the traveling section and the mounting equipment when no load is loaded is known. The internal configuration of the estimating device 100 and the contents of the processing executed by the estimating device 100 will be described in detail later, but in this embodiment, data regarding the magnitude of the oil pressure obtained from the pressure gauge 81 (first data ), data regarding the inclination angle obtained from the inclinometer 82 (second data), and the relationship between data including the loaded weight, the loaded weight of the specially equipped vehicle 1 is estimated. The estimation device 100 is provided inside the cab 20, for example. Alternatively, the estimating device 100 may be attached to the chassis frame 21.

In this embodiment, a dump truck equipped with a dump device 3 will be described as an example of the specially equipped vehicle 1. However, the specially equipped vehicle 1 is not limited to a dump truck, and may include a dump discharge type suction vehicle, a dump discharge type garbage collection vehicle, etc. It may be any specially equipped vehicle equipped with a dumping device.

The configuration of the loaded weight estimation system according to this embodiment will be described below.
FIG. 4 is a block diagram illustrating the configuration of the loaded weight estimation system. The loaded weight display system includes an estimation device 100 that estimates the loaded weight of the specially equipped vehicle 1 based on data regarding the magnitude of oil pressure obtained from the pressure gauge 81 and data regarding the inclination angle obtained from the inclinometer 82; and a display device 120 for reporting information regarding the estimated load weight.

The estimation device 100 is a dedicated or general-purpose computer, and includes a control section 101, a storage section 102, an operation section 103, an input section 104, an output section 105, and a communication section 106.

The control unit 101 includes, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory). The ROM included in the control unit 101 stores a control program, etc. that controls the operation of each hardware unit included in the estimation device 100. The CPU in the control unit 101 executes a control program stored in the ROM and various computer programs stored in the storage unit 102, which will be described later, and controls the operation of each part of the hardware. Realizes the function as 100. The RAM included in the control unit 101 temporarily stores data and the like used during execution of calculations.

The control unit 101 may be equipped with functions such as a clock that outputs date and time information, a timer that measures the elapsed time from when a measurement start instruction is given until a measurement end instruction is given, and a counter that counts the number of measurements. .

The storage unit 102 includes a storage device using a hard disk, flash memory, or the like. The storage unit 102 stores computer programs executed by the control unit 101, various data acquired from the outside, various data generated inside the estimation device 100, and the like.

The computer program stored in the storage unit 102 includes an estimation program PG1 for estimating the loaded weight of the specially equipped vehicle 1 by referring to the relationship between the first data, the second data, and the data including the loaded weight.

The computer program stored in the storage unit 102 is provided, for example, by a non-temporary recording medium RM1 that readably records the computer program. The recording medium RM1 is, for example, a portable memory such as a CD-ROM, a USB memory, or an SD (Secure Digital) card. The control unit 101 uses a reading device (not shown) to read various programs from the recording medium RM1, and stores the read programs in the storage unit 102. Further, the computer program stored in the storage unit 102 may be provided through communication. In this case, the control unit 101 downloads a necessary computer program from a predetermined server, and stores the downloaded computer program in the storage unit 102.

The storage unit 102 also includes a relationship table TB1 that stores the relationship between the inclination angle of the specially equipped vehicle 1 and the magnitude of the oil pressure when the weight and loading position of the loaded object are changed in association with the weight of the loaded object. The configuration of the relationship table TB1 will be detailed later.

The operation unit 103 is composed of switches, buttons, etc., and accepts various operations. The control unit 101 executes appropriate processing based on the operation received through the operation unit 103. Note that in this embodiment, the estimation device 100 is configured to include the operation unit 103, but the operation unit 103 is not essential, and is configured to accept operations via an externally connected device or the communication unit 106. Good too.

The input unit 104 includes an interface for connecting various sensors, and sensors such as a pressure gauge 81 and inclinometers 82 and 83 are connected thereto. These sensors may be connected to the input unit 104 by wire or wirelessly. The input unit 104 includes measurement data related to the cylinder pressure of the hydraulic cylinder 52 output from the pressure gauge 81, measurement data related to the inclination of the specially equipped vehicle 1 outputted from the inclinometer 82, and measurement data related to the inclination of the specially equipped vehicle 1 outputted from the inclinometer 83. Measurement data related to the inclination of the slope, etc. are input as appropriate.

The output unit 105 includes an output interface for connecting a display device 120 such as a liquid crystal monitor. The display device 120 is provided near the driver's seat of the cab 20, for example. Alternatively, the display device 120 may be provided on the rear side of the front panel 41. The output interface provided in the output unit 105 may be an output interface that outputs an analog format video signal, and may be an output interface that outputs a digital format video signal such as DVI (Digital Visual Interface) or HDMI (High-Definition Multimedia Interface, registered trademark). It may also be an output interface that outputs. For example, the output unit 105 outputs display data to the display device 120 in order to display the estimation result of the loaded weight on the display device 120.

In this embodiment, the display device 120 is connected to the outside of the estimating device 100, but the estimating device 100 may be equipped with the display device 120.

The communication unit 106 includes a communication interface that transmits and receives various data to and from external devices. Examples of parties with which the estimation device 100 communicates via the communication unit 106 are various ECUs (Electronic Controller Units) and PLCs (Programmable Logic Controllers) mounted on the specially equipped vehicle 1. In this case, the communication unit 106 may be equipped with a communication port compliant with, for example, RS-485 in order to communicate with various ECUs and PLCs installed in the specially equipped vehicle 1, and may be equipped with a communication port that is compliant with RS-485, for example, for in-vehicle communication such as CAN (Controller Area Network). The communication interface may be provided in accordance with the communication standard. Other examples of parties with which the estimation device 100 communicates via the communication unit 106 include a server device installed outside the specially equipped vehicle 1 and a mobile terminal owned by the user. In this case, the communication unit 106 uses a communication interface compliant with wireless communication standards such as WiFi (registered trademark), 3G, 4G, 5G, and LTE (Long Term Evolution) in order to communicate with an external server device. You may prepare.

The inventors of the present invention have studied in detail the influence of the weight and loading position of the load loaded in the cargo box 4 on the magnitude of hydraulic pressure (cylinder pressure of the hydraulic cylinder 52) and the inclination angle of the specially equipped vehicle 1. Considering the characteristics of the specially equipped vehicle 1, the vehicle (dump truck) can be considered to be supported by "springs" called front wheels 22F, rear wheels 22R, and a leaf suspension (not shown). Therefore, when the cargo box 4 is loaded with cargo, the "spring" is bent by the weight of the cargo, causing the vehicle to tilt. That is, it is expected that there is some relationship between the weight of the loaded object, the loaded position, and the inclination of the vehicle.

FIG. 5 is a graph showing the relationship between the position of the center of gravity of the cargo box 4 containing the load and the change in pitch angle. In the present embodiment, by loading the load whose weight is known into the packing box 4, a state of even loading and a state of maximum unbalanced loading that can realistically occur are created. The position of the center of gravity of the cargo box 4 and the change in the pitch angle of the truck chassis 2 were determined and plotted on a graph. Here, the position of the center of gravity of the cargo box 4 containing the load is calculated using, for example, CAD (Computer-Assisted Design) data. The change in pitch angle represents the difference between the pitch angle of the truck chassis 2 before loading the load and the pitch angle of the truck chassis 2 after loading, and is calculated based on the data obtained from the inclinometer 82. I can do it. Alternatively, the change in pitch angle may be calculated by Computer-Aided Engineering (CAE) analysis.

The change in pitch angle is expressed based on the evenly loaded state in which the loaded items are evenly arranged in the front and back direction of the cargo box 4. That is, in a state of uniform loading, the change in pitch angle is zero. At this time, the pitch angle changes greatly to the negative side, for example, in the maximum uneven loading state where the loaded items are placed biased toward the front of the loading box 4, and the loaded items are placed biased toward the rear of the loading box 4. In the state of maximum uneven loading, for example, there is a large change to the positive side. As shown in the graph of FIG. 5, there is a generally proportional relationship between the inclination of the truck chassis 2 and the position of the center of gravity of the cargo box 4 containing the loaded object.

FIG. 6 is a graph showing the relationship between the oil pressure value and the pitch angle when the loaded weight and loading position are changed. The horizontal axis of the graph represents the pitch angle of the truck chassis 2 obtained from the inclinometer 82, and the vertical axis represents the magnitude of the hydraulic pressure (cylinder pressure of the hydraulic cylinder 52) obtained from the pressure gauge 81. In this embodiment, by loading a load whose weight is known into the cargo box 4, a state of even loading and a state of maximum uneven loading at that weight are created, and in each state, the pitch of the truck chassis 2 is adjusted. The angle and the magnitude of the oil pressure were measured and plotted on a graph.

Specifically, a 10-ton load is placed in order at the front and rear equal loading positions, the front end position, and the rear end position of the cargo box 4, and the pitch angle and hydraulic pressure are measured at each position and the corresponding measures are taken. The measurement points were plotted on the graph. As a result, three measurement points indicated by black circles in the graph of FIG. 6 were obtained. A state in which the loaded items are placed at the front end position and the rear end position of the cargo box 4 corresponds to maximum uneven loading.

Similarly, the pitch angle and The magnitude of the oil pressure was measured and the corresponding measurement points were plotted on the graph. As a result, three measurement points were obtained for each loaded weight. In addition, for loaded items with a loaded weight of 5 tons, 3 tons, 2 tons, and 1 ton, only measurement points were obtained when the loaded items were placed at equal loading positions in the front and rear of the packing box 4, but other loaded weights Similarly, the measurement points when the load is placed at the front end position and the rear end position may also be acquired.

The broken line shown in the graph of FIG. 6 indicates an approximate straight line that approximates three measurement points for each predetermined loaded weight. When the horizontal axis of the graph is the x axis, the vertical axis is the y axis, and the loaded weight is W tons, the approximate straight line is expressed as a _w x+b _w y+c _w =0. Here, x is the pitch angle of the truck chassis 2, y is the oil pressure value, and a _w , b _w , and c _w are coefficients. When measurement results for a loaded weight of W tons (three measurement points in the example of FIG. 6) are obtained, determine the coefficients a _w , b _w , c _w using an approximation method such as the least squares method. Accordingly, an approximate straight line can be derived.

In this embodiment, an approximate straight line is derived using three measurement points obtained in a state of even loading and a state of maximum uneven loading at both front and rear ends. may be added to derive an approximate straight line from four or more measurement points. Further, in this embodiment, the measurement point is approximated by a straight line, but it may be approximated by any arbitrary curve such as a quadratic curve or a cubic curve.

In addition, in order to more accurately estimate the loaded weight near the maximum loading capacity (for example, 10 tons) of the specially equipped vehicle 1, we increased the number of measurement points when the maximum loading capacity was loaded and derived a more accurate approximate curve. Alternatively, approximate curves around the maximum load capacity (for example, approximate curves of 9.8 tons, 9.9 tons, 10.1 tons, and 10.2 tons) may be derived.

The estimation device 100 includes a relationship table TB1 that stores the relationship between the pitch angle of the truck chassis 2 and the hydraulic pressure when the loaded weight and loading position are changed in association with the loaded weight. FIG. 7 is a conceptual diagram showing an example of the relationship table TB1. In the relationship table TB1, by storing the above-mentioned coefficients a _w , b _w , c _w for each loaded weight, it is possible to calculate the relationship between the pitch angle of the truck chassis 2 and the hydraulic pressure when the loaded weight and loading position are changed. remember the relationship between For example, since the approximate straight line for a loaded weight of 10 tons can be expressed as a ₁₀ x+b ₁₀ y+c ₁₀ =0, the relationship between the pitch angle of the truck chassis 2 and the hydraulic pressure can be obtained from the equation of this straight line. The same holds true for other relationships in loaded weight. In this embodiment, it is assumed that the coefficients a _w , b _w , and c _w for each load weight are determined in advance through preliminary analysis before the start of operation. Note that each of the coefficients a _w , b _w , c _w may be determined using actual measured values, or may be determined using the results of CAE analysis.

In this embodiment, the coefficients a _w , b _w , and c _w are stored for each loaded weight, but an equation representing an approximate straight line (a ₁₀ x+b ₁₀ y+c ₁₀ =0) is stored in the storage unit 102. You can also use it as Furthermore, although the relationship table TB1 has been described as defining the relationship between the pitch angle of the truck chassis 2 and the magnitude of the oil pressure, it does not define the relationship between the roll angle of the truck chassis 2 and the magnitude of the oil pressure. It's okay.

The estimation device 100 acquired, through the input unit 104, data regarding the magnitude of the oil pressure obtained from the pressure gauge 81 (first data), and data regarding the inclination angle of the specially equipped vehicle 1 obtained from the inclinometer 82 (second data). In this case, the loaded weight in the cargo box 4 is estimated by referring to the relationship stored in the relationship table TB1.

FIG. 8 is an explanatory diagram illustrating a method for estimating the loaded weight in the first embodiment. The control unit 101 of the estimation device 100 plots an approximate straight line when the relationships stored in the relationship table TB1 are plotted on a two-dimensional coordinate plane and the measurement results indicated by the first data and the second data on the same two-dimensional coordinate plane. The loaded weight in the cargo box 4 is estimated based on the distance between the measurement points plotted above.

When the approximate straight line for the loaded weight W is a _w x + b _w y + c _w = 0, and the coordinates of the measurement point are (X, Y), the distance between the approximate straight line and the measurement point is the perpendicular line from the measurement point to the approximate straight line. It is equal to the length of the perpendicular when lowered, and is calculated by |a _w X+b _w Y+c _w |/(a _w ² +b _w ² ) ^1/2 .

When the control unit 101 acquires the first data and the second data, the control unit 101 calculates the distance between each approximate straight line and the measurement point by specifying the coordinates representing the measurement point and substituting them into the above calculation formula. The control unit 101 estimates the loaded weight in the cargo box 4 based on the calculated distance. For example, as shown in FIG. 8, a case will be described in which a measurement point exists between the approximate straight line of the loaded weight W1 and the approximate straight line of the loaded weight W2. When the distance from the measurement point to the approximate straight line of the loaded weight W1 is calculated as L1, and the distance from the measured point to the approximate straight line of the loaded weight W2 is calculated as L2, the control unit 101 calculates, for example, W1×L2/(L1+L2)+W2. The loaded weight at the measurement point can be estimated by distributing it by a distance ratio such as ×L1/(L1+L2).

Note that in cases where there is no need to estimate the loaded weight in detail, the control unit 101 may estimate the loaded weight by specifying the approximate straight line closest to the measurement point. For example, in the example of FIG. 8, since the measurement point is closest to the approximate straight line of the loaded weight W1, the loaded weight at the measured point may be estimated to be W1.

The procedure for estimating the loaded weight will be explained below.
FIG. 9 is a flowchart illustrating the procedure for estimating the loaded weight in the first embodiment. The control unit 101 of the estimation device 100 reads the estimation program PG1 from the storage unit 102 and executes it while the cargo box 4 is at a predetermined dump angle (for example, 1.0 degrees) with respect to the truck chassis 2. Execute the following processing.

The control unit 101 acquires first data regarding the magnitude of oil pressure based on the output from the pressure gauge 81 (step S101). Specifically, the control unit 101 acquires the first data by acquiring measurement data (hydraulic pressure value of the hydraulic cylinder 52) output from the pressure gauge 81 through the input unit 104.

The control unit 101 acquires second data regarding the inclination angle of the specially equipped vehicle 1 based on the output from the inclinometer 82 (step S102). Specifically, the control unit 101 acquires the second data by acquiring measurement data (pitch angle and roll angle of the specially equipped vehicle 1) output from the inclinometer 82 through the input unit 104.

The control unit 101 specifies the coordinates of the measurement point on the two-dimensional coordinate plane based on the acquired first data and second data (step S103). When the magnitude of the oil pressure indicated by the first data is X and the pitch angle indicated by the second data is Y, the coordinates of the measurement point are expressed as (X, Y).

The control unit 101 identifies two approximate straight lines sandwiching the measurement point identified in step S103 (step S104). For example, the control unit 101 determines the magnitude of the hydraulic pressure when the pitch angle is X from each approximate straight line, and examines the difference between the hydraulic magnitude Y at the measurement point and the hydraulic magnitude determined from the approximate straight line. , two approximate straight lines sandwiching the measurement point can be specified.

The control unit 101 calculates the distance between the measurement point and the two identified approximate straight lines (step S105). The control unit 101 reads the coefficients a _w , b _w , c _w that define each approximate straight line from the relational table TB1, and uses the coordinates (X, Y) specified in step S103 and the coefficients a w , c _w that define each approximate straight line. By substituting b _w and c _w into the above-mentioned arithmetic expression, the distance between the measurement point and each approximate straight line can be calculated.

The control unit 101 estimates the loaded weight based on the ratio of distances from the measurement point to each approximate straight line (step S106). For example, assume that the approximate straight line located below the measurement point is the approximate straight line of the loaded weight W1, and the distance to the approximate straight line is L1. Further, it is assumed that the approximate straight line located above the measurement point is the approximate straight line of the loaded weight W2, and the distance to the approximate straight line is L2. In this case, the control unit 101 can estimate the loaded weight by calculating, for example, W1×L2/(L1+L2)+W2×L1/(L1+L2).

The control unit 101 notifies the estimated loaded weight (step S107). At this time, the control unit 101 outputs information on the estimated loaded weight from the output unit 105 and displays it on the display device 120. FIG. 10 is a schematic diagram showing an example of displaying the loaded weight. FIG. 10 shows an example in which the estimated value of the loaded weight, the loading rate, and the estimated date and time information are displayed on the display device 120 as text information. Here, the estimated value of the loaded weight is the value of the loaded weight estimated with reference to the relationship table TB1. The loading rate is a value calculated as a ratio of the loaded weight (estimated value) to the upper limit value. The estimated date and time is the date and time when the loaded weight was estimated, and is information obtained from the built-in clock of the control unit 101, for example. The control unit 101 generates display screen data based on the estimated value of the loaded weight estimated with reference to the relational table TB1, the loading rate calculated as a ratio to the upper limit value, and the date and time information obtained from the built-in clock, By outputting the generated display screen data to the display device 120, a screen as shown in FIG. 10 can be displayed on the display device 120.

As described above, in the first embodiment, when the angle of inclination and the magnitude of the hydraulic pressure of the specially equipped vehicle 1 are obtained, the loaded weight is estimated by referring to the relation table TB1 that defines the relationship between the specially equipped vehicle 1 and the loaded weight. It is possible to accurately estimate the loaded weight and notify the estimated loaded weight regardless of the presence or absence of the slope.

(Embodiment 2)
Hereinafter, a method for estimating the loaded weight in the second embodiment will be explained.
FIG. 11 is an explanatory diagram illustrating a method for estimating the loaded weight in the second embodiment. The control unit 101 of the estimation device 100 plots an approximate straight line when the relationships stored in the relationship table TB1 are plotted on a two-dimensional coordinate plane and the measurement results indicated by the first data and the second data on the same two-dimensional coordinate plane. The loaded weight in the cargo box 4 is estimated based on the distance between the measurement points plotted above.

In the second embodiment, instead of using the length of the perpendicular line drawn from the measurement point to each approximate straight line, a straight line passing through the measurement point is used. Specifically, the control unit 101 identifies two approximate straight lines that sandwich the measurement point between them, and identifies a line segment that passes through the measurement point and connects the identified two approximate straight lines at the shortest possible distance. Then, the control unit 101 finds the intersections between the identified line segments and the approximate straight lines, and estimates the loaded weight according to the ratio of the distances from the measurement points to each intersection.

As shown in FIG. 11, a case where a measurement point exists between the approximate straight line of the loaded weight W1 and the approximate straight line of the loaded weight W2 will be described. The control unit 101 finds the intersections between the straight line passing through the measurement point and each approximate straight line, calculates the distance between the intersections, and identifies the line segment with the minimum distance between the intersections. Let P1 be the intersection of the loaded weight W1 with the approximate curve, and P2 be the intersection of the loaded weight W2 with the approximate curve. If the distance from the measurement point to the intersection P1 is L1, and the distance from the measurement point to the intersection P2 is L2, the control unit 101 calculates the following: W1×L2/(L1+L2)+W2×L1/(L1+L2), for example. By distributing the load based on the distance ratio, the loaded weight at the measurement point can be estimated.

(Embodiment 3)
In the third embodiment, a configuration will be described in which the loaded weight is estimated by distinguishing between a state in which the cargo box 4 is raised and then stopped, and a state in which the cargo box 4 is lowered and then stopped.

The inventors of the present application investigated in detail the relationship between the pitch angle of the truck chassis 2 and the oil pressure value, and found that the oil pressure value when the cargo box 4 is raised and then stopped is different from that after the cargo box 4 is lowered. It was found that there is a difference between the oil pressure value when the engine is stopped and the oil pressure value when the engine is stopped. Therefore, in the loaded weight estimation system in the third embodiment, a state in which the packing box 4 is stopped after being raised and a state in which the packing box 4 is stopped after being lowered are distinguished, and a different relationship table is used for both to estimate the loaded weight. Estimate.

FIG. 12 is a block diagram illustrating the configuration of a loaded weight estimation system in the third embodiment. The estimation device 100 includes a control section 101, a storage section 102, an operation section 103, an input section 104, an output section 105, and a communication section 106. The configuration of each of these hardware parts is the same as that described in Embodiment 1, so the description thereof will be omitted.

The storage unit 102 includes a relational table TB10 for stopping ascent and a relational table TB20 for stopping descending. The relationship table TB10 for stopping the lift determines approximate straight lines for each predetermined loaded weight based on the data on the inclination angle and hydraulic pressure of the specially equipped vehicle 1 acquired while the cargo box 4 is stopped after being lifted, and calculates each approximate straight line. This is a table in which coefficients of straight lines are stored in association with loaded weights. Similarly, the relationship table TB20 for descending and stopping determines an approximate straight line for each predetermined loaded weight based on data on the inclination angle and hydraulic pressure of the specially equipped vehicle 1 obtained when the cargo box 4 is stopped after descending. , is a table in which the coefficients of each approximate straight line are stored in association with the loaded weight.

FIG. 13 is a flowchart illustrating the procedure for estimating the loaded weight in the third embodiment. The control unit 101 of the estimating device 100 determines whether the metering switch 89 is turned on by monitoring the signal input through the input unit 104 (step S301). If the metering switch 89 is not turned on (S301: NO), the control unit 101 waits until the metering switch 89 is turned on.

When the weighing switch 89 is turned on (S301: YES), the control unit 101 starts the process of estimating the loaded weight. When starting the estimation process, the user may be instructed to adjust the dump angle to a predetermined angle. The predetermined angle is, for example, an angle greater than 0.5 degrees and less than 1.5 degrees. The control unit 101 may give instructions by displaying text information or the like on the display device 120, or may give instructions by outputting audio from a speaker (not shown). In the third embodiment, the dump angle is manually adjusted using the operating lever 67.

The control unit 101 sequentially acquires, through the input unit 104, measurement data of the inclination angle measured in time series by the inclinometers 82 and 83, and detects the current dump angle based on the acquired measurement data (step S302). The control unit 101 can determine the dump angle by subtracting the inclination angle of the truck chassis 2 obtained as the measurement value of the inclinometer 82 from the inclination angle of the cargo box 4 obtained as the measurement value of the inclinometer 83. The control unit 101 causes the storage unit 102 to store the detected dump angles in chronological order.

The control unit 101 determines whether the dump angle detected in step S302 is larger than the minimum angle θ1 (step S303). The minimum angle θ1 is a value set as the minimum value of the angle range suitable for measuring the loaded weight of the cargo box 4. An example of the minimum angle θ1 is 0.5 degrees.

If it is determined that the current dump angle is less than or equal to the minimum angle θ1 (S303: NO), the control unit 101 instructs the user to raise the cargo box 4 (Step S304). The control unit 101 instructs the user by displaying text information on the display device 120 indicating that the packing box 4 should be raised. Alternatively, the control unit 101 may instruct the user to raise the cargo box 4 by outputting a voice from a speaker (not shown). Upon receiving the instruction, the user operates the operating lever 67 to raise the cargo box 4 by an appropriate angle and stop it. After instructing the user, the control unit 101 returns the process to step S302.

When determining that the current dump angle is larger than the minimum angle θ1 (S303: YES), the control unit 101 determines whether the current dump angle is smaller than the maximum angle θ2 (step S305). The maximum angle θ2 is a value set as the maximum value of an angular range suitable for measuring the loaded weight of the cargo box 4. An example of the maximum angle θ2 is 1.5 degrees.

If it is determined that the current dump angle is greater than or equal to the maximum angle θ2 (S305: NO), the control unit 101 instructs the user to lower the cargo box 4 (Step S306). The control unit 101 instructs the user, for example, by displaying text information on the display device 120 indicating that the packing box 4 should be lowered. Alternatively, the control unit 101 may instruct the user to lower the packing box 4 by outputting a sound from a speaker (not shown). Upon receiving the instruction, the user operates the operating lever 67 to lower and stop the cargo box 4 by an appropriate angle. After instructing the user, the control unit 101 returns the process to step S302.

If it is determined that the current dump angle is smaller than the maximum angle θ2 (S305: YES), the control unit 101 refers to the output of the built-in timer and determines that a predetermined period of time has elapsed since the dump angle entered the set angle range. It is determined whether or not it has been done (step S307). If the predetermined time has not elapsed (S307: NO), the control unit 101 waits until the predetermined time has elapsed.

If it is determined that the predetermined time has elapsed (S307: YES), the control unit 101 determines whether the packing box 4 has been in a stopped state until the predetermined time has elapsed (step S308). The control unit 101 can determine whether or not the cargo box 4 is in a stopped state by determining the presence or absence of a change from the dump angle history data stored in the storage unit 102. If it is not in the stopped state (S308: NO), the control unit 101 returns the process to step S302.

If the packing box 4 is in a stopped state until the predetermined time has elapsed (S308: YES), the control unit 101 notifies the user that preparations for weighing the loaded weight are ready (Step S309). For example, the control unit 101 causes the display device 120 to display text information indicating that preparations for weighing the loaded weight are ready. Alternatively, the control unit 101 may cause a speaker (not shown) to output a sound indicating that the weighing of the loaded weight is ready.

Next, the control unit 101 determines whether the cargo box 4 has stopped after being raised (step S310). The control unit 101 can determine whether the cargo box 4 has stopped after being raised from the dump angle history data stored in the storage unit 102.

When the control unit 101 determines that the cargo box 4 has stopped after being raised (S310: YES), the control unit 101 selects the relation table TB10 for stopping the rise as a table to be referred to when estimating the loaded weight (Step S311). On the other hand, when the control unit 101 determines that the cargo box 4 has stopped after being lowered (S310: NO), it selects the relation table TB20 for lowering and stopping as the table to be referred to when determining the loaded weight (step S312).

The control unit 101 acquires first data (data related to the magnitude of oil pressure) based on the measurement results of the pressure gauge 81 and second data (data related to the inclination of the specially equipped vehicle 1) based on the measurement results of the inclinometer 82, By referring to the relationship table TB10 for stopping ascent selected in step S311 or the relationship table TB20 for stopping ascent selected in step S312, the loaded weight in the cargo box 4 is estimated (step S313).

The method described in Embodiment 1 or Embodiment 2 can be used as a method for estimating the loaded weight. That is, the control unit 101 calculates the distance between the measurement point indicated by the first data and the second data and two approximate straight lines sandwiching this measurement point, and adjusts the loading according to the ratio of the calculated distances. Weight can be estimated.

Next, the control unit 101 notifies the estimated loaded weight (step S314). At this time, the control unit 101 outputs information on the estimated loaded weight from the output unit 105 and displays it on the display device 120. The control unit 101 may display the loaded weight information as text information on the display device 120, or may use a schematic display method such as a graph display or a meter display. Further, the control unit 101 may be configured to output information on the estimated loaded weight as audio from a speaker not shown in the figure. After completing these series of processes, the user operates the operating lever 67 to lower the cargo box 4 until the dump angle becomes 0 degrees. Thereafter, the weighing switch 89 is turned off, thereby ending the weighing.

In Embodiment 3, a state in which the packing box 4 is stopped after being raised and a state in which the packing box 4 is stopped after being lowered are distinguished, and the loaded weight is estimated using different relational tables for both. Compared to the case where estimation is performed using a common table, deterioration in estimation accuracy can be suppressed.

(Embodiment 4)
In Embodiment 4, a configuration that automatically performs the lifting stop operation will be described.

FIG. 14 is a block diagram illustrating the configuration of a loaded weight estimation system according to the fourth embodiment. The loaded weight estimation system according to the fourth embodiment includes an estimation device 100 and a lift control device 200 connected to the estimation device 100. Estimation device 100 is similar to that described in Embodiment 3, and includes a control section 101, a storage section 102, an operation section 103, an input section 104, an output section 105, and a communication section 106. In addition, in the fourth embodiment, only the relation table TB10 for stopping the movement upward is used, so the relation table TB20 for stopping the movement downward does not need to be stored in the storage unit 102.

The elevation control device 200 includes an input section 201, a control section 202, and an output section 203, and controls the elevation of the cargo box 4 by controlling the operation of a hydraulic mechanism included in the specially equipped vehicle 1. The input unit 201 includes an input interface. Information output from the estimation device 100, operation information of the control lever 67, operation information of the PTO switch 72, etc. are input to the input unit 201. Information input to the input section 201 is output to the control section 202.

The control unit 202 is configured by, for example, a PLC (Programmable Logic Controller). The control unit 202 generates a control signal for controlling the lifting and lowering of the cargo box 4 based on information input through the input unit 201 according to programmed logic. The control unit 202 outputs the generated control signal to the control valve 63 from the output unit 203. The output unit 203 includes an output interface, and is connected to the control valve 63, the estimation device 100, and the like. Note that the control valve 63 in the fourth embodiment is configured as an electrically controllable electromagnetic control valve.

In the present embodiment, the loaded weight estimation system has a configuration in which the estimation device 100 and the elevation control device 200 are separately provided, but the two may be configured as an integrated unit.

FIG. 15 is a flowchart illustrating the procedure for estimating the loaded weight in the fourth embodiment. The control unit 101 of the estimating device 100 determines whether the metering switch 89 is turned on by monitoring the signal input through the input unit 104 (step S401). If the metering switch 89 is not turned on (S401: NO), the control unit 101 waits until the metering switch 89 is turned on.

If the metering switch 89 is turned on (S401: YES), the control unit 101 determines whether the PTO switch 72 is turned on (step S402). If the PTO switch 72 is not on (S402: NO), the control unit 101 instructs the user to turn on the PTO switch 72 (step S403), and switches the power transmission destination of the engine 70 to the hydraulic pump 61. . Instructions to the user may be given by displaying text information on the display device 120, or may be given by outputting audio from a speaker (not shown).

If the PTO switch 72 is on (S402: YES), the control unit 101 notifies the user that the dump angle will be adjusted (Step S404). For example, the control unit 101 causes the display device 120 to display text information indicating that the dump angle is to be adjusted. Alternatively, the control unit 101 may output a sound indicating that the dump angle is to be adjusted from a speaker (not shown).

Next, the control unit 101 instructs the elevation control device 200 to raise the cargo box 4 (step S405). Specifically, the control unit 101 generates a control signal that instructs the lifting of the cargo box 4, and outputs the generated control signal from the output unit 105 to the lifting control device 200, thereby issuing an instruction to the lifting control device 200. I do. The control unit 202 of the elevation control device 200 raises the cargo box 4 by outputting a control signal for raising the cargo box 4 to the control valve 63 in response to an instruction from the estimation device 100.

The control unit 101 sequentially acquires, through the input unit 104, measurement data of the inclination angle measured in time series by the inclinometers 82 and 83, and detects the current dump angle based on the acquired measurement data (step S406).

The control unit 101 determines whether the dump angle detected in step S406 is larger than the minimum angle θ1 (step S407). The minimum angle θ1 is a value set as the minimum value of the angle range suitable for measuring the loaded weight of the cargo box 4. An example of the minimum angle θ1 is 0.5 degrees.

If it is determined that the current dump angle is less than or equal to the minimum angle θ1 (S407: NO), the control unit 101 returns the process to step S405 and continues the lifting control of the cargo box 4.

If it is determined that the current dump angle is larger than the minimum angle θ1 (S407: YES), the control unit 101 determines whether the current dump angle is smaller than the maximum angle θ2 (step S408). The maximum angle θ2 is a value set as the maximum value of an angular range suitable for measuring the loaded weight of the cargo box 4. An example of the maximum angle θ2 is 1.5 degrees.

If it is determined that the current dump angle is greater than or equal to the maximum angle θ2 (S408: NO), the control unit 101 determines that the inclination angle of the cargo box 4 is outside the angle range suitable for measuring the loaded weight. An error is notified (step S409), and the processing according to this flowchart is ended. After notifying the error, the control unit 101 may instruct the elevation control device 200 to lower the cargo box 4.

If it is determined that the current dump angle is smaller than the maximum angle θ2 (S408: YES), the control unit 101 instructs the loading box 4 to stop after being raised (step S410). Specifically, the control unit 101 generates a control signal that instructs to stop the loading box 4, and outputs the generated control signal from the output unit 105 to the elevation control device 200, thereby issuing an instruction to the elevation control device 200. I do. The control unit 202 of the lift control device 200 stops the cargo box 4 by outputting a control signal for stopping the cargo box 4 to the control valve 63 in response to the instruction from the estimation device 100.

Next, the control unit 101 notifies the user that preparations for weighing the loaded weight are ready (step S411). For example, the control unit 101 causes the display device 120 to display text information indicating that preparations for weighing the loaded weight are ready. Alternatively, the control unit 101 may cause a speaker (not shown) to output audio information indicating that preparations for weighing the loaded weight are ready.

Next, the control unit 101 sets the relation table TB10 for stopping the lift as a table to be referred to when estimating the loaded weight (step S412). The control unit 101 acquires first data (data related to the magnitude of oil pressure) based on the measurement results of the pressure gauge 81 and second data (data related to the inclination of the specially equipped vehicle 1) based on the measurement results of the inclinometer 82, The loaded weight in the cargo box 4 is estimated by referring to the relation table TB10 for lifting and stopping set in step S412 (step S413).

The method described in Embodiment 1 or Embodiment 2 can be used as a method for estimating the loaded weight. That is, the control unit 101 calculates the distance between the measurement point indicated by the first data and the second data and two approximate straight lines sandwiching this measurement point, and adjusts the loading according to the ratio of the calculated distances. Weight can be estimated.

Next, the control unit 101 notifies the estimated loaded weight (step S414). At this time, the control unit 101 outputs information on the estimated loaded weight from the output unit 105 and displays it on the display device 120. The control unit 101 may display the loaded weight information as text information on the display device 120, or may use a schematic display method such as a graph display or a meter display. Further, the control unit 101 may be configured to output information on the estimated loaded weight as audio information from a speaker (not shown).

After estimating the loaded weight and notifying the user, the control unit 101 may give an instruction to the lift control device 200 to lower the cargo box 4. The control unit 202 of the lift control device 200 may lower the cargo box 4 by outputting a control signal for lowering the cargo box 4 to the control valve 63 in response to an instruction from the estimation device 100.

When manually measuring the loaded weight, it is necessary to adjust the dump angle to a predetermined angle (for example, 1.0 degrees), which may make the user feel that the operation is troublesome. In contrast, in the present embodiment, the loaded weight can be automatically measured by operating the weighing switch 89, so that the troublesome operation can be reduced.

(Embodiment 5)
In Embodiment 5, a configuration will be described in which the loaded weight is estimated using a common relationship table TB30 when the loading box 4 is raised and then stopped, and when the loading box 4 is lowered and then stopped. do.

FIG. 16 is a block diagram illustrating the configuration of a loaded weight estimation system in the fifth embodiment. The estimation device 100 includes a control section 101, a storage section 102, an operation section 103, an input section 104, an output section 105, and a communication section 106. The configuration of each of these hardware parts is the same as that described in Embodiment 1, so the description thereof will be omitted.

The storage unit 102 includes a common relation table TB30 for cases in which the packing box 4 is raised and then stopped, and when the packing box 4 is lowered and then stopped. The configuration of the relationship table TB30 is the same as the relationship table TB1 described in the first embodiment, and shows the relationship between the inclination angle of the specially equipped vehicle 1 and the magnitude of the oil pressure when the weight and loading position of the loaded object are changed. It is stored in association with the weight of the loaded object.

In the fifth embodiment, it is assumed that the relationship between the oil pressure value measured after the cargo box 4 stops rising and the oil pressure value measured after the cargo box 4 stops descending is known in advance. For example, when the measurement conditions are the same, there is a relationship of PV1 = PV2 + ΔPV between the oil pressure value PV1 measured after the loading box 4 stops rising and the oil pressure value PV2 measured after the loading box 4 stops lowering. Assume that there is. ΔPV is the differential pressure between PV1 and PV2, and is assumed to be known in the fifth embodiment. A relational expression indicating this relationship is stored in the storage unit 102.

When the control unit 101 obtains the oil pressure value (=PV1) and inclination angle measured after the ascent is stopped, the control unit 101 estimates the loaded weight by referring to the relational table TB30 based on the obtained oil pressure value and inclination angle. On the other hand, when the control unit 101 acquires the oil pressure value (=PV2) and the inclination angle measured after the descent is stopped, the control unit 101 corrects the oil pressure value PV2 according to the relational expression stored in the storage unit 102. That is, the control unit 101 performs correction by adding the difference ΔPV to the obtained oil pressure value PV2. The control unit 101 estimates the loaded weight by referring to the relational table TB30 based on the corrected oil pressure value (=PV2+ΔPV) and the inclination angle.

FIG. 17 is a flowchart illustrating the procedure for estimating the loaded weight in the fifth embodiment. The control unit 101 of the estimating device 100 completes the weighing preparation by following the same steps as S301 to S309 in the flowchart shown in FIG. 13, and notifies the user that the weighing of the loaded weight is ready (steps S501 to S509). ). After the weighing preparation is completed, the loading operation is performed. The control unit 101 acquires first data (oil pressure value) based on the measurement result of the pressure gauge 81 and second data (inclination angle of the specially equipped vehicle 1) based on the measurement result of the inclinometer 82 at any time.

After notifying the user that preparations for weighing the loaded weight are ready, the control unit 101 determines whether the cargo box 4 has stopped after being raised in the processes from S501 to S508 (step S510). When the control unit 101 determines that the cargo box 4 has stopped after being raised (S510: YES), the control unit 101 estimates the loaded weight with reference to the relational table TB30 based on the obtained oil pressure value and inclination angle (Step S511). The method of estimating the loaded weight using relational table TB30 is the same as in the first embodiment.

On the other hand, when the control unit 101 determines that the cargo box 4 has stopped after being lowered (S510: NO), it adds the differential pressure ΔPV to the oil pressure value P2 after the lowering is stopped (step S512). Thereafter, the control unit 101 proceeds to step S511, and estimates the loaded weight with reference to the relational table TB30 based on the oil pressure value (=PV2+ΔPV) to which the differential pressure has been added and the inclination angle (step S511). The method of estimating the loaded weight using relational table TB30 is the same as in the first embodiment.

Next, the control unit 101 notifies the estimated loaded weight (step S513). At this time, the control unit 101 outputs information on the estimated loaded weight from the output unit 105 and displays it on the display device 120. The control unit 101 may display the loaded weight information as text information on the display device 120, or may use a schematic display method such as a graph display or a meter display. Further, the control unit 101 may be configured to output information on the estimated loaded weight as audio from a speaker not shown in the figure. After completing these series of processes, the user operates the operating lever 67 to lower the cargo box 4 until the dump angle becomes 0 degrees. Thereafter, the weighing switch 89 is turned off, thereby ending the weighing.

As described above, in the fifth embodiment, since the relationship between the oil pressure value measured after the ascent is stopped and the oil pressure value measured after the descent is stopped, for example, the oil pressure value measured after the descent is stopped is , it is possible to correct the oil pressure value to the same value as the oil pressure value after stopping the rise measured under the same conditions. Therefore, there is no need to prepare two types of relational tables (a relational table for raising and stopping and a relational table for lowering and stopping) in order to estimate the load weight from the oil pressure value, and the storage capacity of the storage unit 102 is relatively small. Even the estimation device 100 can estimate the loaded weight.

In this embodiment, the differential pressure is added to the oil pressure value obtained after the descent is stopped, but the differential pressure may be subtracted from the oil pressure value obtained after the ascent is stopped. Furthermore, instead of adding (or subtracting) the differential pressure, any one of the hydraulic pressure values may be corrected using any relational expression.

(Embodiment 6)
In Embodiment 6, a configuration for estimating the loaded weight using a learning model will be described.

FIG. 18 is a schematic diagram showing a configuration example of the learning model LM1. The learning model LM1 in this embodiment is, for example, a support vector regression model, and includes an input layer into which various data are input, an intermediate layer including a kernel that performs a predetermined calculation based on the data input to the input layer, and an intermediate layer that includes a kernel that performs a predetermined calculation based on the data input to the input layer. and an output layer that combines outputs from the layers and outputs calculation results.

One or more nodes exist in the input layer, middle layer, and output layer of the learning model LM1, and the nodes in each layer are connected in one direction to the nodes in the previous and subsequent layers using connection weights. Note that in a support vector machine that is nonlinearly expanded using a kernel trick, the connection weight from the intermediate layer to the output layer is adaptively determined by learning. On the other hand, the connection weight from the input layer to the hidden layer is fixed and mechanically determined from training data.

First data (data related to the magnitude of oil pressure) and second data (data related to the inclination of the specially equipped vehicle 1) are input to the input layer of the learning model LM1. Data input to the input layer is weighted by connection weights determined using training data and output to the intermediate layer. The intermediate layer executes calculations using kernels based on data input from the input layer. The data calculated in each kernel of the intermediate layer is weighted by the connection weight determined by learning and output to the output layer. The output layer outputs a calculation result regarding the loaded weight by combining the data input from the intermediate layer.

Here, the calculation result output by the output layer may be an estimated value of the loaded weight, or may be a probability corresponding to a certain loaded weight. In the latter case, the output layer is composed of a plurality of nodes, the probability that the loaded weight is 1 ton from the first node, the probability that the loaded weight is 2 tons from the second node, ..., the Nth node (N is an integer greater than or equal to 2), it is sufficient to output the probability of a certain loaded weight, such as the probability that the loaded weight is N tons.

The learning model LM1 may be prepared in the storage unit 102 included in the estimation device 100, or may be provided in an external server device that is communicably connected to the estimation device 100.

The estimating device 100 can estimate the loaded weight by inputting data obtained during loading work into the learning model LM1 and obtaining calculation results by the learning model LM1.

The embodiments disclosed herein are illustrative in all respects and should not be considered restrictive. The scope of the present invention is indicated by the claims, not the above-mentioned meaning, and is intended to include meanings equivalent to the claims and all changes within the scope.

For example, in the present embodiment, the specially equipped vehicle 1 is a dump truck that includes an estimation device 100 that estimates a loaded weight, a display device 120 that notifies information about the loaded weight estimated by the estimation device 100, and a dump device 3. Although described above, the present invention is applicable not only to dump trucks but also to various specially equipped vehicles equipped with a dump device having a hydraulic cylinder. For example, it can be applied to specially equipped vehicles such as a dump discharge type suction vehicle, a dump discharge type garbage collection vehicle, and a container removal vehicle equipped with a cargo handling arm.

1 Specially equipped vehicle 2 Truck chassis 3 Dump device 4 Load box 5 Hoist mechanism 20 Cab 21 Chassis frame 22F Front wheel 22R Rear wheel 23F, 23R Axle 30 Subframe 81 Pressure gauge 82 Inclinometer (chassis)
83 Inclinometer (packing box)
100 Estimation device 101 Control unit 102 Storage unit 103 Operation unit 104 Input unit 105 Output unit 106 Communication unit PG1 Estimation program TB1 Relationship table

Claims (8)

With respect to a specially equipped vehicle equipped with a hydraulic actuator for raising and lowering a cargo box, a first acquisition unit that acquires first data regarding the magnitude of the hydraulic pressure from a pressure gauge that measures the magnitude of the hydraulic pressure acting on the hydraulic actuator;
a second acquisition unit that acquires second data regarding the tilt angle from an inclinometer that measures the tilt angle of the specially equipped vehicle;
a storage unit that stores a plurality of relationships between the inclination angle and the magnitude of the hydraulic pressure when the weight and loading position of the loaded object are changed, in association with the weight of the loaded object;
A system for estimating a loaded weight of a specially equipped vehicle, comprising: an estimating unit that estimates a loaded weight in the cargo box by referring to a relationship stored in the storage unit when the first data and the second data are acquired. The estimation unit is configured to calculate an approximate curve when the relationship is plotted on a two-dimensional coordinate plane, and a measurement point when measurement results indicated by the first data and the second data are plotted on the two-dimensional coordinate plane. The loaded weight estimation system according to claim 1, wherein the loaded weight is estimated based on the distance between the loaded weight and the loaded weight. The loaded weight estimation system according to claim 2, wherein the estimator estimates the loaded weight by identifying an approximate curve closest to the measurement point. The estimation unit specifies two approximate curves that sandwich the measurement point between them, and estimates the loaded weight according to a ratio of distances from the measurement point to the two identified approximate curves. Loaded weight estimation system. The estimation unit calculates a length ratio of each perpendicular line when a perpendicular line is drawn from the measurement point to the two approximate curves, and estimates the loaded weight according to the calculated ratio. Loaded weight estimation system. The estimating unit identifies a line segment that passes through the measurement point and connects the two approximate curves at the shortest distance, determines the intersection between the identified line segment and each approximate curve, and calculates the distance from the measurement point to each intersection. The loaded weight estimation system according to claim 4, wherein a ratio is calculated, and the loaded weight is estimated according to the calculated ratio. Regarding a specially equipped vehicle equipped with a hydraulic actuator for raising and lowering a cargo box, first data regarding the magnitude of the hydraulic pressure is obtained from a pressure gauge that measures the magnitude of the hydraulic pressure acting on the hydraulic actuator;
obtaining second data regarding the inclination angle from an inclinometer that measures the inclination angle of the specially equipped vehicle;
When the first data and the second data are acquired, the relationship between the inclination angle and the magnitude of the oil pressure when the weight and loading position of the loaded object is changed is associated with the weight of the loaded object. A method for estimating a loaded weight of a specially equipped vehicle, in which a computer executes a process of estimating a loaded weight in the cargo box by referring to a plurality of storage units. to the computer,
Regarding a specially equipped vehicle equipped with a hydraulic actuator for raising and lowering a cargo box, first data regarding the magnitude of the hydraulic pressure is obtained from a pressure gauge that measures the magnitude of the hydraulic pressure acting on the hydraulic actuator;
obtaining second data regarding the inclination angle from an inclinometer that measures the inclination angle of the specially equipped vehicle;
When the first data and the second data are acquired, the relationship between the inclination angle and the magnitude of the oil pressure when the weight and loading position of the loaded object is changed is associated with the weight of the loaded object. A computer program for executing a process of estimating a loaded weight in the cargo box by referring to a plurality of storage units.

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