JP2023148202A - Work machine - Google Patents

Abstract

To provide a work machine capable of accurately grasping the position of a suspended load relative to the work machine.SOLUTION: A work machine (100) is capable of suspending a load. The work machine (100) includes: a measurement unit (20, 21, 22, 23) that measures a position of a suspended load (N) relative to the work machine (100); and a control unit (40) that calibrates the measurement unit (20, 21, 22, 23).SELECTED DRAWING: Figure 2

Description

The present invention relates to a working machine capable of suspending a load.

Patent Document 1 describes a detection device that is attached to a crane and detects the spatial position and attitude of a boom. The detection device performs the above detection by measuring the distance and direction to the target mark provided at the tip of the boom.

Japanese Patent Application Publication No. 2014-181092

In a working machine that performs work by suspending a load, it is preferable to be able to accurately grasp the position of the suspended load relative to the working machine.

An object of the present invention is to provide a working machine that can more accurately grasp the position of a suspended load relative to the working machine.

The present invention
A working machine capable of suspending loads,
a measuring unit for measuring the position of the suspended load with respect to the working machine;
a control unit that calibrates the measurement unit;
Equipped with

Advantageous Effects of Invention According to the present invention, it is possible to accurately determine the position of a suspended load relative to a working machine.

1 is a diagram showing a working machine according to Embodiment 1 of the present invention. FIG. 2 is a block diagram showing the configuration of a control system of the work machine shown in FIG. 1. FIG. The principle of calculation of the position of a suspended load is explained, and (A) is a diagram showing the arrangement relationship between a boom, a photographing device, and a suspended load, and (B) is a diagram showing an image of the photographing device. It is a figure explaining the calibration process of the coordinate of an image, and is a graph (A) which shows the positional change of a suspended load, and a figure (B) which shows the coordinate before and after calibration. 7 is a flowchart showing a calibration mode process according to the first embodiment executed by a control unit. It is a figure showing the work machine concerning Embodiment 2 of the present invention. FIG. 7 is a block diagram showing the configuration of a control system of the work machine shown in FIG. 6; FIG. 7 is a diagram illustrating the principle of measuring the position of a suspended load in Embodiment 2.

Embodiments of the present invention will be described in detail below with reference to the drawings. In this specification, the position of a suspended load means the position of the load when the load is being hung, and the position of the hanging tool (for example, hook) 107 when the load is not suspended. In addition, the length of the rope that moves up and down the hanging tool 107 (the length of the portion that is let out before the point sheave 106a) is referred to as the "rope length."

(Embodiment 1)
FIG. 1 shows a working machine according to Embodiment 1 of the present invention, in which (A) is a side view and (B) is a plan view. In FIG. 1(B), the boom 106, rope (wire rope), etc. are omitted. FIG. 2 is a block diagram showing the configuration of the control system of the working machine.

The work machine 100 of Embodiment 1 is a mobile crane, and includes a lower traveling body 102, an upper rotating body 104 that can rotate with respect to the lower traveling body 102, and a boom 106 that can raise and lower with respect to the upper rotating body 104. , and a hanging tool 107 suspended from the tip of the boom 106. The upper revolving body 104 is provided with a cab 112 that is a driver's cab. Further, the work machine 100 includes a plurality of winches 114 that wind up and let out a rope that raises and lowers the hanging tool 107, and wind up and let out a rope that raises and lowers the boom 106, respectively.

As shown in FIG. 2, the cab 112 includes, in addition to a driving operation section 115, an operation section 116 for switching operation modes, a display device 117 that can output various videos or images, and various information through sounds and displays. A notification unit 118 that notifies the user may also be provided.

The work machine 100 further includes a boom overwinding prevention device (for example, a backstop) 108 that limits excessive rotation of the boom 106 in the up-and-down direction, and a hook overwinding prevention device 109 that limits excessive lifting of the hoist 107. .

The boom over-winding prevention device 108 restricts the boom 106 from excessive rotation in the up-and-down direction by locking the boom 106 so that the angle in the up-and-down direction of the boom 106 stops at a set angle. The boom overwind prevention device 108 includes a buffer mechanism to prevent impact from being applied when the boom 106 is locked, but when the boom 106 stops due to the activation of the boom overwind prevention device 108, the boom 106 is configured to stably stop at a set angle. Furthermore, when the boom 106 is locked, the boom overwinding prevention device 108 outputs a signal indicating the locking to the control unit 40.

The hook overwinding prevention device 109 is a limit switch for stopping winding of the wire rope for suspending the hanging tool 107 when the hanging tool 107 rises from the point sheave 106a to the position of the set length. The hook overwind prevention device 109 is activated by the lifting of the hanging tool 107, and when the hanging tool 107 stops, the rope length is configured to stably reach the set length.

As shown in FIG. 2, the working machine 100 includes a measuring section 20 for measuring the position of the suspended load with respect to the working machine 100, and a calculating section 30 for calculating the position of the suspended load based on the measurement result of the measuring section 20. , and a control section 40 that controls the work machine 100. The control unit 40 may be a computer, and the calculation unit 30 may be a part of the control unit 40.

The measurement unit 20 includes an imaging device 21 attached to the boom 106, a boom angle measurement unit 22 that measures the undulation angle of the boom 106, and a rope length of the hanging tool 107 (the length of the rope that moves up and down the lifting tool 107). It includes a rope length measuring section 23 for measuring.

The photographing device 21 is a digital photographing device or the like having a lens and an image sensor, and when the photographing direction is known, the coordinate value (x ₁ , y ₁ ), the direction of the suspended load N can be determined. The photographing device 21 is attached around the tip of the boom 106 at a predetermined angle so that the suspended load N is included in the viewing angle.

The mounting angle of the photographing device 21 may be variable by driving the movable device 21F (servo motor or the like). Further, by attaching the photographing device 21 to the boom 106 via a slide mechanism such as a rack and pinion, the fixed position of the photographing device 21 may be variable by driving the movable device 21F (servo motor or the like). In the case of this configuration, the mounting angle and mounting position of the photographing device 21 can be determined from data representing the drive amount of each servo motor.

A configuration may be adopted in which the image E of the photographing device 21 is output to the display device 117 of the cab 112, and the worker can confirm the suspended load N from the image E.

The boom angle measurement unit 22 is an encoder that detects the amount of rotation of the winch 114 that winds up and lets out the rope that raises and lowers the boom 106, an angle meter attached to the boom 106, or a boom Any configuration may be used as long as it is possible to measure the up-and-down angle of the boom 106, such as an encoder that detects the amount of rotation of the boom 106.

The rope length measurement unit 23 measures the length of the rope let out from the tip of the boom 106. More specifically, the rope length may be defined, for example, as the length from the end point where the rope separates in the point sheave 106a to a predetermined point on the hanging tool 107. The rope length measurement unit 23 may be configured to output a signal capable of measuring the rope length, such as an encoder that detects the amount of rotation of the winch 114 that raises and lowers the hanging tool 107, or an encoder that detects the amount of rotation of the point sheave 106a. Any configuration may be used.

Video data is sent to the calculation unit 30 from the photographing device 21 . When the mounting angle, the mounting position, or both of the mounting angle and the mounting position of the imaging device 21 are variable, the data indicating the mounting angle, the mounting position, or both of these are sent to the calculation unit from the control unit 40 that controls the mounting angle and the mounting position. Sent to 30. Furthermore, measurement data from the boom angle measurement section 22 and the rope length measurement section 23 is sent to the calculation section 30 .

The calculation unit 30 calculates the relative position of the suspended load N using the tip of the boom 106 as a reference point P ₀ based on the following principle. FIG. 3 is a diagram illustrating the principle of calculation of the position of a suspended load, in which (A) is a diagram showing the arrangement relationship between the boom, the photographing device, and the suspended load, and (B) is a diagram showing an image of the photographing device.

The calculation unit 30 obtains the angle θ _boom of the boom 106 based on the measurement data of the boom angle measurement unit 22. Furthermore, the calculation unit 30 obtains the rope length L _hook from the measurement data of the rope length measurement unit 23.

Further, the calculation unit 30 calculates the length L _cam1 from the reference point P ₀ of the boom 106 to the attachment position P ₁ of the imaging device 21 and the mounting angle θ _cam0 from the data on the mounting position and the mounting angle of the imaging device 21. get. Further, the length L _cam2 from the attachment position P ₁ to the viewing angle center point P ₂ is a constant value, and the calculation unit 30 holds the value of the length L _cam2 in advance.

The calculation unit 30 calculates a vector A _cam1 from the reference point P ₀ to the attachment position P ₁ from the length L _cam1 and the angle θ _boom of the boom 106. Furthermore, the calculation unit 30 calculates a vector A _cam2 from the mounting position P1 to the viewing angle center point P ₂ from the length L _cam2 , the mounting angle θ _cam0 of the photographing device 21, and the angle θ _boom of the boom 106. do.

Furthermore, the calculation unit 30 performs image recognition of the hanging load from the video data, and obtains the coordinate values (x ₁ , y ₁ ) of the hanging load N in the video E (FIG. 3(B)). Image recognition may be replaced by recognition using a machine-learned learning model (artificial intelligence). Then, the calculation unit 30 calculates angles θ _camx and θ _camy from the imaging center line L _cam0 corresponding to the coordinate values (x ₁ , y ₁ ). The angles θ _camx and θ _camy correspond to an angle in the x direction and an angle in the y direction in the viewing angle of the photographing device 21, and have a one-to-one correspondence with the coordinate values in the video.

Furthermore, the calculation unit 30 geometrically calculates the intersection between the spherical surface Sn having the reference point P ₀ as the center and the rope length L _hook as the radius, and the straight line extending from the viewing angle center point P ₂ at angles θ _camx and θ _camy . Calculate to. Then, the calculation unit 30 calculates the distance from the viewing angle center point _P2 to the above-mentioned intersection. Furthermore, a vector A _CtoN from the viewing angle center point P ₂ to the suspended load N is calculated from the distance and the angles θ _camx , θ _camy , θ _boom , and θ _cam0 .

When the vectors A _cam1 , A _cam2 , and A _CtoN are obtained through the above calculation, the calculation unit 30 combines these vectors A _cam1 , A _cam2 , and A _CtoN to determine the tip of the boom 106 (reference point P It is possible to obtain the relative position (=A _cam1 +A _cam2 +A _CtoN ) of the hanging load N with respect to ₍ A cam1 +A cam2 +A CtoN). The calculation unit 30 sends the calculation result of the relative position of the suspended load N to the control unit 40.

In this way, the control unit 40 of the work machine 100 can accurately grasp the relative position of the suspended load N, thereby enabling the control unit 40 to calculate various useful physical quantities. For example, by separately providing data on the weight of the suspended load N, the control unit 40 uses these data to determine in what direction and how much load is applied to the boom 106 when the suspended load N swings. It becomes possible to find out.

In addition to controlling the operation of the work machine 100, the control unit 40 performs calibration processing of the measurement unit 20.

<Proofreading process>
As described above, the calculation unit 30 can accurately determine the relative position of the suspended load N based on the measurement data of the measurement unit 20. On the other hand, systematic errors may be added to the measurement data of the measurement unit 20. For example, in the boom angle measuring section 22, a systematic error may occur in the measurement data such that a substantially constant deviation is added to the true undulation angle. Also in the rope length measuring section 23, systematic errors may occur in the measurement data, such as adding a substantially constant deviation to the true rope length.

In such a case, the boom angle measuring section 22 can be calibrated by measuring the deviation between the true up-and-down angle of the boom 106 and the measured data, and removing the deviation from the subsequent measurement data. Similarly, the rope length measuring section 23 can be calibrated by measuring the deviation between the true rope length and the measured data and removing the deviation from the subsequent measurement data.

Further, when the photographing device 21 is fixedly attached to the boom 106, the attachment angle may shift due to vibration or the like. Alternatively, when the photographing device 21 is movably attached to the boom 106, the control data for the attachment position, attachment angle, or both may indicate a value that deviates from the true value. In these cases, the above-mentioned deviation is added to the angle indicating the direction of the suspended load N calculated based on the image E as a systematic error.

In such a case, the deviation between the true mounting angle of the imaging device 21 and the mounting angle recognized by the control unit 40 is measured, and subsequent control data for the mounting angle is corrected so that the deviation is removed. This makes it possible to calibrate the mounting angle control data used for angle measurement by the photographing device 21. The same applies to the control data for the mounting position of the photographing device 21.

The control unit 40 executes the process of calibrating the systematic errors described above for each element of the measurement unit 20 as follows.

In the calibration process of the boom angle measuring section 22, the control section 40 raises and lowers the boom 106 to a known angle by driving the winch 114, and calculates the difference between the measurement data of the boom angle measuring section 22 at that time and the known angle. Measure the deviation that occurs in the measurement data. Then, when the deviation is measured, the control unit 40 executes a calibration process so that a value obtained by subtracting the deviation from the measurement data of the boom angle measuring unit 22 is output.

The angle of the boom 106 at which the calibration process of the boom angle measurement unit 22 is performed may be a set angle when the boom overwinding prevention device 108 restricts the rotation of the boom 106 in the up-and-down direction. By employing this angle, the control unit 40 can obtain the true angle of the boom 106 and perform the calibration process of the boom angle measurement unit 22 without adding a means to measure the true angle of the boom 106 for calibration. can be carried out.

In addition, in the calibration process of the boom angle measuring section 22, the control section 40 does not drive the winch 114, but the control section 40 outputs support information to the worker of the working machine 100, so that the worker can Alternatively, the winch 114 may be operated to rotate the boom 106 to a levitation angle that can be calibrated. Further, the angle of the boom 106 at which the calibration process of the boom angle measurement unit 22 is performed is not limited to the above-mentioned angle, and various predetermined angles may be employed. For example, a camera photographs a part of the boom 106 moving from a fixed position, and based on the fact that the boom 106 is reflected in a predetermined position, the boom angle is adjusted to match the angle of the boom 106 corresponding to the time of photographing. The measuring section 22 may be calibrated.

In the calibration process of the rope length measuring section 23, the control section 40 winds (or lets out) the rope suspending the hanging tool 107 to a known length by driving the winch 114, and uses the measurement data of the rope length measuring section 23 at that time. The deviation occurring in the measurement data is measured from the difference between the measured length and the above-mentioned known length. Then, when the deviation is measured, the control unit 40 executes a calibration process so that a value obtained by subtracting the deviation from the measurement data of the rope length measuring unit 23 is output.

The rope length on which the calibration process of the rope length measurement unit 23 is performed may be the set length of the rope when the hook overwinding prevention device 109 restricts the lifting of the hanging tool 107. By employing the set length, the control unit 40 obtains the true lobe length and performs the calibration process of the rope length measuring unit 23 without adding a means for measuring the true rope length for calibration. be able to.

In addition, in the calibration process of the rope length measuring section 23, the control section 40 does not drive the winch 114, but the control section 40 outputs support information to the worker of the working machine 100, so that the worker can Alternatively, the winch 114 may be driven so that the rope length can be adjusted to a length that can be calibrated.

In the process of calibrating the mounting angle of the photographing device 21, the control unit 40 utilizes a posture sensor (for example, IMU (Inertial Measurement Unit)) 25 attached to the photographing device 21. The posture sensor 25 is attached to the photographing device 21 , measures the angle of the photographing device 21 with respect to the horizontal, and outputs measurement data to the control unit 40 . The control unit 40 calculates the attachment angle of the photographing device 21 with respect to the boom 106 from the output of the attitude sensor 25 and the measurement result of the boom angle measurement unit 22. Then, the control unit 40 calculates the difference between the mounting angle held by the control unit 40 and the calculated mounting angle as a deviation from the true mounting angle, and adjusts the mounting angle so that the deviation is removed. By correcting the represented control data, calibration processing regarding the mounting angle is performed.

Further, when the mounting position of the photographing device 21 is variable, the control unit 40 moves the photographing device 21 to a location where the position is known, such as one end of the movable range. That is, the control unit 40 drives the movable device 21F (servo motor for movement) in one direction, and stops the movable device 21F when the photographing device 21 and the servo motor no longer move. Then, the control unit 40 calculates the difference between the mounting position of the photographing device 21 calculated from the control data of the servo motor at that time and the mounting position of the photographing device 21 obtained from the end point position of the slide mechanism to determine the true mounting position. Calculated as the deviation from Then, the control unit 40 performs a calibration process regarding the mounting position by correcting the control data representing the mounting position so that the deviation is removed.

FIG. 4 is a diagram illustrating the process of calibrating the coordinates of an image, and includes a graph (A) showing changes in the position of the hanging load and a diagram (B) showing the coordinates before and after the calibration.

Calibration processing of the coordinates (x, y) in the image E of the photographing device 21 is performed as follows. In other words, when the wind is weak and a suspended load N with a small deviation in the center of gravity is suspended, the suspended load N is a pendulum that includes swinging components in two horizontal directions about a point vertically below the tip of the point sheave 106a. Do exercise. If the suspended load N is located at the center of the pendulum movement, the rope suspending the hanging tool 107 should extend vertically downward.

In addition, when the rope extends vertically downward, which coordinate position in the image E is determined from the rope length L _hook , the angle θ _boom of the boom 106, the mounting position (length L _cam1 ) and the mounting angle θ _cam0 of the photographing device 21? It is possible to back-calculate where the suspended load N should be located.

Therefore, the control unit 40 determines the true coordinate position where the above-mentioned suspended load N is supposed to be located and the coordinate position (x ₂ , y ₂ ) ( 4(A) and FIG. 4(B)), and calculate the difference between them as a coordinate shift. The calculation for determining the coordinate position of the center point of the pendulum movement may be replaced by an acquisition process using a machine-learned learning model (artificial intelligence).

Then, the control unit 40 calibrates the origin of the coordinates so that the above deviation is removed. Note that the coordinates (x, y) may be displayed on the display device 117 in a superimposed manner with the image E, and the origin of the coordinates displayed on the display device 117 may also be corrected when the coordinates are calibrated. Alternatively, the coordinate calibration is performed only on the coordinates in the video E that the control unit 40 recognizes through internal processing (data values of the coordinate origin included in the control data used by the control unit 40), and the coordinates are not output to the display device 117. It does not need to be reflected in the coordinates.

<Calibration mode processing>
FIG. 5 is a flowchart showing the calibration mode process of the first embodiment executed by the control unit. The above-described calibration process of the measurement unit 20 is executed when the operation mode of the work machine 100 is switched to the calibration mode. The operation mode may be switchable to a calibration mode by a worker or the like operating an operation unit 116 provided in the cab 112. The operation unit 116 may be an operation unit displayed on a display screen such as a touch panel.

In addition, in the calibration mode, when the wind strength is below a predetermined value, when the operation is not in progress, when the hanging tool 107 is not on the ground, when the lifting tool 107 is not rotating, and when the levelness of the work site is above a predetermined value. Alternatively, the control may be such that the transition can be made when a predetermined condition is satisfied, such as when a plurality of these conditions are satisfied. Work machine 100 may be equipped with an anemometer and a level in order to determine whether conditions are met.

When the calibration mode process is started by operating the operation unit 116, the control unit 40 first determines whether the conditions for transitioning to the calibration mode are satisfied (step S1), and if YES, the notification unit 118 Output in the calibration mode is performed (step S2), and the process proceeds. On the other hand, if the result of step S1 is NO, the control unit 40 ends the calibration mode process.

As the process progresses, first, the control unit 40 executes a calibration process for the boom angle measurement unit 22 (step S3). In step S3, as an example, the control unit 40 outputs support information to rotate the boom 106 until the boom overwind prevention device 108 is activated, and the worker rotates the boom 106 based on the support information. Then, in a state where the boom overwinding prevention device 108 is activated and the boom 106 is stably at the set angle, the control unit 40 performs the calibration process of the boom angle measurement unit 22 as described above.

Next, the control unit 40 executes a calibration process for the rope length measuring unit 23 (step S4). As an example, in step S4, the control unit 40 outputs support information to raise the hanging tool 107 until the hook overwinding prevention device 109 is activated, and the worker raises the hanging tool 107 based on the support information. Then, when the hook overwinding prevention device 109 is activated and the hanging tool 107 is stopped, and the rope length has stably reached the set length, the control section 40 performs the calibration process of the rope length measuring section 23 as described above. carry out.

By performing the calibration process for the rope length measuring section 23 (step S4) after the calibration process for the boom angle measuring section 22 (step S3), it is possible to reduce the number of necessary driving operations by the operator. That is, when the boom 106 is rotated to an angle at which the boom overwind prevention device 108 is activated, the rope suspending the hanging tool 107 is pulled somewhat toward the point sheave 106a due to the rotation. Therefore, in order to rotate the boom 106 to an angle at which the boom overwind prevention device 108 is activated, the length of the rope hanging the hanging device 107 must be made longer than the length at which the hook overwind prevention device 109 is activated. There is. Therefore, if the order of steps S3 and S4 is reversed, after the rope length reaches the set length in the calibration process of the rope length measuring section 23, the rope suspending the hanging tool 107 is let out, and then the boom angle is measured. It becomes necessary to move on to the calibration process of the section 22. On the other hand, by setting the order from step S3 to step S4, it is possible to omit the process of letting out the rope for hanging the above-mentioned hanging tool 107.

Next, the control unit 40 executes a process of calibrating the mounting angle and mounting position of the imaging device 21 (step S5). A specific example of the calibration process is as described above.

Finally, the control unit 40 executes a process of calibrating the coordinates of the image E (step S6). A specific example of the calibration process is as described above.

After that, the control unit 40 ends the output of the calibration mode from the notification unit 118 (step S7), and ends the calibration mode processing.

By calibrating the measurement unit 20 through the above-described calibration mode processing, it becomes possible to more accurately grasp the position of the suspended load N after that.

As described above, the working machine 100 of the first embodiment includes the measuring section 20 for measuring the position of the suspended load N with respect to the working machine 100, and the control section 40 for calibrating the measuring section 20. Therefore, systematic errors in the measurement unit 20 can be removed through calibration, and the working machine 100 can accurately grasp the position of the suspended load N by using accurate measurement data.

Furthermore, according to the working machine 100 of the first embodiment, the control unit 40 calibrates the mounting angle, the mounting position, and the coordinates of the image E of the photographing device 21. Further, the control unit 40 calibrates the boom angle measurement unit 22 and the rope length measurement unit 23. Therefore, the work machine 100 can accurately grasp the position of the suspended load N with respect to the boom 106 from the video data of the photographing device 21 and the measurement data of the boom angle measuring section 22 and the rope length measuring section 23. .

Furthermore, according to the working machine 100 of the first embodiment, the rope length measuring section 23 is calibrated based on the operation of the hook overwinding prevention device 109, so that stable calibration processing is possible, and furthermore, the rope length is adjusted to a predetermined value. There is no need to add a means for detecting the length for calibration processing.

Further, according to the work machine 100 of the first embodiment, the boom angle measuring section 22 is calibrated when the boom 106 reaches a predetermined angle, so that stable calibration processing is possible. Furthermore, the above-mentioned predetermined angle is an angle at which the boom overwind prevention device 108 operates. Setting such an angle eliminates the need for additional means for detecting that the boom 106 has reached a predetermined angle for calibration processing.

Furthermore, according to the work machine 100 of the first embodiment, the control unit 40 executes the calibration process of the measurement unit 20 when the calibration mode is selected. Therefore, it is easy to carry out well-conditioned and accurate calibration. It is possible to prevent problems such as incorrect calibration processing being performed without the operator noticing.

(Embodiment 2)
FIG. 6 is a diagram showing a working machine according to Embodiment 2 of the present invention. FIG. 7 is a block diagram showing the configuration of the control system of the work machine shown in FIG. 6. The working machine 100A of the second embodiment is the same as the first embodiment, except that the elements of the measuring unit 20A for measuring the position of the suspended load N with respect to the working machine 100A and the content of the calibration process are different. Elements are given the same reference numerals as in Embodiment 1, and detailed explanations are omitted.

The measuring unit 20A of the second embodiment includes a rope length measuring unit 23 that measures the rope length, a first positioning device 26 attached to the boom 106, and a second positioning device 27 attached to the hanging tool 107 or the suspended load N. including. The first positioning device 26 may be attached, for example, to the reference point _P0 of the boom 106 or around it.

The first positioning device 26 and the second positioning device 27 are positioning devices that utilize GNSS (Global Navigation Satellite System), and in this embodiment, positioning data of latitude and longitude are mainly used.

FIG. 8 is a diagram illustrating the principle of measuring the position of a suspended load in the second embodiment. The calculation unit 30A obtains horizontal positioning data (X _P0 , Y _P0 ) and (X _hook , Y _hook ) from the first positioning device 26 and the second positioning device 27, respectively. Furthermore, the calculation unit 30A obtains the rope length L _hook from the rope length measurement unit 23.

From these data, the calculation unit 30A calculates the relative position A _0toN of the suspended load N with respect to the reference point P ₀ of the boom 106. That is, the distance in the horizontal X direction and Y direction can be calculated from the positioning data (X _P0 , Y _P0 ) and (X _hook , Y _hook ). Furthermore, the distance in the vertical Z direction can be calculated geometrically from the positioning data (X _P0 , Y _P0 ), (X _hook , Y _hook ) and the rope length L _hook . Then, as components in the X, Y, and Z directions, a vector having the distances in the X, Y, and Z directions is the position vector A _0toN from the reference point P ₀ to the suspended load N, = (X _0toN , Y _0toN , _Z0toN ).

The measurement unit 20A includes a direction device that measures the direction in which the boom 106 is facing, and the calculation unit 30A calculates the measurement result of the direction device and the latitude and longitude of the first positioning device 26 and the second positioning device 27. By associating the data, the relative position of the suspended load N with respect to the reference point P ₀ of the boom 106 may be calculated, including the direction.

The control unit 40A of the second embodiment executes a process of calibrating the rope length measuring unit 23 and a process of calibrating the mounting positions of the first positioning device 26 and the second positioning device 27. The calibration process of the rope length measuring section 23 is as shown in the first embodiment.

Calibration processing regarding the first positioning device 26 and the second positioning device 27 is performed as follows. In other words, when the wind is weak and a suspended load N with a small deviation in the center of gravity is suspended, the suspended load N is a pendulum that includes swinging components in two horizontal directions about a point vertically below the tip of the point sheave 106a. Do exercise. If the suspended load N is located at the center of the pendulum movement, the rope suspending the hanging tool 107 should extend vertically downward. That is, the first positioning device 26 and the second positioning device 27 should be located at the same latitude and longitude.

Therefore, the control unit 40A calculates the latitude and longitude of the center point of the pendulum movement from the positioning data of the second positioning device 27. Furthermore, the difference between the latitude and longitude indicated by the positioning data of the first positioning device 26 and the latitude and longitude of the center point of the pendulum movement is calculated as the difference in the mounting position of the first positioning device 26 or the second positioning device 27. Then, the control unit 40A offsets the positioning data of the first positioning device 26 or the second positioning device 27 so that the deviation is removed. The offset corresponds to calibration processing. Note that the first positioning device 26 and the second positioning device 27 may be installed at positions that differ in latitude and longitude by a predetermined amount of deviation, and in this case, positioning is performed using an offset amount that includes the amount of deviation. Calibration processing may be performed so that the data is corrected. In addition, the calibration process of the first positioning device 26 and the second positioning device 27 uses another sensor to measure the actual position of the first positioning device 26 and the second positioning device 27 or the amount of deviation between the positions of each other, It may be performed based on the measurement results.

Also in the second embodiment, the control unit 40A may be configured to execute the calibration process when the operation mode of the working machine 100 is switched to the calibration mode. The operation mode may be switchable to a calibration mode by a worker or the like operating an operation unit 116 provided in the cab 112. Furthermore, in the calibration mode, when the wind strength is below a predetermined value, when the operation is not in progress, when the lifting tool 107 is not on the ground, when the lifting tool 107 is not rotating, and when the levelness of the work site is above a predetermined value. Alternatively, the control may be such that the transition can be made when a predetermined condition is satisfied, such as when a plurality of these conditions are satisfied.

As described above, the working machine 100A of the second embodiment includes the measuring section 20A for measuring the position of the suspended load N with respect to the working machine 100A, and the control section 40A for calibrating the measuring section 20A. Therefore, the systematic errors of the measurement unit 20A can be removed through calibration, and the working machine 100A can accurately grasp the position of the suspended load N by using the measurement data from which the systematic errors have been removed.

Furthermore, according to the working machine 100A of the second embodiment, the measurement unit 20A includes the first positioning device 26 attached to the boom 106 and the second positioning device 27 attached to the suspended load N or the hanging tool 107. , the control unit 40A calibrates the first positioning device 26, the second positioning device 27, or both by adding an offset to the positioning data. With such a configuration, the position of the suspended load N can be easily and accurately determined with a small number of measurement processes. Furthermore, the calibration process can be performed in a short time.

Each embodiment of the present invention has been described above. However, the present invention is not limited to the above embodiments. For example, in the above embodiment, a mobile crane which is a crawler crane is shown as a working machine, but in addition to other mobile cranes such as wheel cranes and truck cranes, port cranes, overhead cranes, jib cranes, and gantry cranes are also available. It is applicable to all types of cranes, including fixed cranes such as , unloaders, etc. Further, the working machine may be any machine as long as it can hang a load, such as a shovel that suspends the load using a held rope.

In addition, in the above embodiment, an example was shown in which the mode is shifted to the calibration mode based on the operator's operation. It is also possible to issue a notification recommending the transition to the mode, or to automatically transition to the calibration mode. In addition, details shown in the embodiments, such as detailed definitions of reference points and rope lengths, can be changed as appropriate without departing from the spirit of the invention.

20, 20A Measuring unit 21 Photographing device 22 Boom angle measuring unit 23 Rope length measuring unit 26 First positioning device 27 Second positioning device 30, 30A Calculation unit 40, 40A Control unit 100, 100A Working machine 106 Boom 106a Point sheave 107 Lifting Tools 108 Boom overwinding prevention device 109 Hook overwinding prevention device 112 Cab 114 Winch 116 Operation section 117 Display device 118 Notification section N Hanging load E Image P ₀ reference point

Claims (9)

A working machine capable of suspending loads,
a measuring unit for measuring the position of the suspended load with respect to the working machine;
a control unit that calibrates the measurement unit;
A working machine equipped with The measurement unit includes a photographing device for photographing the suspended load,
The control unit calibrates the mounting angle, mounting position, or both of the data of the photographing device.
A working machine according to claim 1. The measurement unit includes a photographing device for photographing the suspended load,
The control unit calibrates the coordinates of the image of the imaging device.
A working machine according to claim 1 or claim 2. The measurement unit includes a boom angle measurement unit, a rope length measurement unit that measures the length of the rope for hanging the load, or both thereof,
The control unit calibrates the boom angle measurement unit, the rope length measurement unit, or both.
A working machine according to any one of claims 1 to 3. The control unit calibrates the rope length measuring unit based on the operation of a hook overwinding prevention device that prevents overwinding of a rope for hanging a load.
The working machine according to claim 4. The control unit calibrates the boom angle measurement unit when the boom reaches a predetermined angle.
The working machine according to claim 4. The predetermined angle is an angle at which a boom overwinding prevention device that prevents the wire rope hoisting the boom from being overwound operates;
The control unit calibrates the boom angle measurement unit based on the operation of the boom overwind prevention device.
A working machine according to claim 6. The measurement unit includes a first positioning device attached to the boom and a second positioning device attached to the hanging load or hanging tool,
The control unit calibrates the first positioning device, the second positioning device, or both by adding an offset to the positioning data.
A working machine according to any one of claims 1 to 7. calibrating the measuring section upon receiving an input to transition to the calibration mode;
A working machine according to any one of claims 1 to 8.

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