JP6759628B2 - Swing angle arithmetic unit of suspended load - Google Patents

Description

The present invention relates to, for example, a technique for calculating the swing angle of a suspended load suspended from a traversing trolley in a crane for cargo handling work used in a port, a steel mill, various factories, and the like.

In general, in cargo handling work using a crane, it is ideal to accurately reach the target position in a short time and to make the swing angle of the suspended load zero until or when the target position is reached. ..
Various steady rest control techniques for making the runout angle of a suspended load zero have been conventionally provided, but in recent years, computer-controlled electric steady rest control has attracted attention.

For electrical steady rest control, a speed pattern that attenuates the runout at the end of acceleration / deceleration is calculated, and this speed pattern is used as a control command to operate a crane or detect the runout angle of a suspended load and detect it. Some control the value by feeding it back to the drive system.
Of these, a runout angle detection device is required for feedback control, but even in the case of control using a speed pattern, a runout angle detection device is often provided to guarantee control performance. .. The swing angle of the suspended load in the crane can be roughly classified into a sway swing angle that swings in the transverse direction of the trolley and a skew swing angle that twists around the vertical axis.

Here, FIG. 9 shows a main part of the runout angle detection device described in Patent Document 1, FIG. 9A is a side view showing the overall configuration of the crane, and FIG. 9B is a side view. It is a top view of the target installed in the hanging tool.

In FIG. 9A, 51 is a trolley, 52 is a wire, 53 is a hanging tool, 54 is a target installed on the upper surface of the hanging tool 53, and a camera 55 is installed on the lower surface of the trolley 51. As shown in FIG. 9B, for example, a band-shaped marker (or a semiconductor light emitting element or the like) 54a is provided in the central portion of the target 54, and an image captured by the marker 54a taken by the camera 55 is imaged by a computer. By processing, the moving state of the hanging tool 53 is detected, and the runout angle of the suspended load (not shown) integrally held by the hanging tool 53 is calculated.

Further, as another conventional technique, in Patent Document 2, a plurality of targets are arranged on the upper surface of the hanger, and a wide-angle camera and a telephoto camera are arranged on the lower surface of the trolley corresponding to each target. A runout angle detecting device for detecting a sway runout angle and a skew runout angle of a suspended load based on a temporal change in the position of the center of gravity obtained from images captured by a plurality of cameras is disclosed.

Japanese Unexamined Patent Publication No. 6-219681 (paragraphs [0011] to [0021], FIGS. 1, 2, etc.) Japanese Unexamined Patent Publication No. 9-257475 (paragraphs [0021] to [0024], FIGS. 1, 2, etc.)

Here, assuming outdoor use of a container crane or the like, as described in Patent Document 1, when the deflection angle is detected based on the image captured by the camera, sunlight, fog, rainfall, etc. at the time of shooting, etc. Susceptible to optical disturbances. For this reason, there is a problem that an erroneous detection of a runout angle or a detection error occurs temporarily, and the runout angle cannot be detected stably.
Further, as described in Patent Document 2, it is possible to prevent erroneous detection and detection error to some extent by using a plurality of cameras, but the cost of the device is high due to the plurality of cameras and their image processing means. Was invited.

Therefore, the problem to be solved by the present invention is to estimate the runout angle by arithmetic processing and perform the runout control without any trouble even if a runout angle erroneous detection or a detection error occurs temporarily. The purpose is to provide an arithmetic unit.

In order to solve the above problems, the invention according to claim 1 is a runout angle arithmetic unit that generates a runout angle estimated value by calculating a runout angle detection value of a suspended load suspended from a traversing trolley at a predetermined cycle. In
A detection value abnormality determination unit that determines normality / abnormality of the deflection angle detection value input to the runout angle calculation device,
The previous estimated value / angular velocity storage unit that calculates the runout angle velocity from the runout angle estimated value in the previous calculation cycle and saves the runout angle estimated value and the runout angle velocity,
When the detection value abnormality determination unit determines that it is normal, the first process of generating the runout angular velocity detection value as the current runout angular velocity estimation value is performed, and when the detection value abnormality determination unit determines that it is abnormal, the previous time. The runout angle estimation unit that performs the second processing to calculate the current runout angle estimation value based on the runout angle estimation value and the runout angle velocity of the previous calculation cycle saved in the estimated value / angular velocity storage unit.
With
The runout angle estimation unit
When there are a plurality of types of the runout angle detection values, the first processing is performed on the runout angle detection value determined to be normal by the detection value abnormality determination unit among the plurality of runout angle detection values, and The second process is performed on the remaining runout angle detection values determined to be abnormal .

The invention according to claim 2 is a runout angle arithmetic unit that generates a runout angle estimation value by calculating a runout angle detection value of a suspended load suspended from a traversing trolley according to a predetermined cycle, and the runout angle estimation. The value is in the runout angle arithmetic unit used to generate the actuator position command for steady rest control.
A detection value abnormality determination unit that determines normality / abnormality of the deflection angle detection value input to the runout angle calculation device,
When it is determined to be normal by the detection value abnormality determination unit, the runout angular velocity estimated value is obtained from the runout angle detection value, the actuator position command or the actuator position detection value, and the runout angle estimated value of the previous calculation cycle, and the runout is found. The first process of generating the current runout angle estimated value from the angular velocity estimated value and the runout angle detection value is performed, and when the detection value abnormality determination unit determines that the abnormality is found, the actuator position command or the actuator position detection value is used. And the deflection angle estimation unit that obtains the deflection angular velocity estimated value from the deflection angle estimated value of the previous calculation cycle and performs the second processing to generate the current deflection angular velocity estimated value from the said deflection angular velocity estimated value.
It is equipped with.

The invention according to claim 3 is the swing angle calculation device for a suspended load according to claim 2 , wherein the swing angle estimation unit is among a plurality of swing angle detection values when there are a plurality of types of the swing angle detection values. The first process is performed on the runout angle detection value determined to be normal by the detection value abnormality determination unit, and the second process is performed on the remaining runout angle detection values determined to be abnormal. It is something to do.

The invention according to claim 4 is the swing angle calculation device for a suspended load according to any one of claims 1 to 3, wherein the detection value abnormality determination unit calculates the input current swing angle detection value and the previous calculation. When the deviation from the estimated swing angle of the cycle exceeds a predetermined determination threshold value, it is determined to be abnormal.

The invention according to claim 5 is the swing angle calculation device for a suspended load according to claim 4, wherein the detection value abnormality determination unit uses the input current runout detection value and the runout angle estimation value of the previous calculation cycle. When the deviation of is equal to or less than a predetermined determination threshold value continues for a certain period of time, it is determined to be normal, and when the deviation exceeds the determination threshold value, it is immediately determined to be abnormal.

In the invention according to claim 6, in the swing angle calculation device of the suspended load according to any one of claims 1 to 5, the runout angle detection value includes a skew runout angle detection value and a sway runout angle detection value. It is characterized by that.

The invention according to claim 7 is a captured image of a target that moves the runout angle detection value integrally with the suspended load in the swing angle calculation device of the suspended load according to any one of claims 1 to 6. It is obtained based on.

According to the present invention, even if a false detection or a detection error of the runout angle occurs temporarily, the runout angle can be estimated by arithmetic processing, so that the runout angle used for the steady rest control can be stably obtained. Is. Further, since it is not indispensable to use a plurality of imaging devices such as cameras, it also contributes to cost reduction.

It is a functional block diagram of the swing angle arithmetic unit which concerns on 1st Embodiment of this invention. It is a block diagram which shows the main part of the crane to which each embodiment of this invention is applied, and the sway runout angle. It is a top view of the hanging tool in FIG. It is explanatory drawing of the skew runout angle. It is explanatory drawing of the sway runout angle and skew runout angle in the XYZ coordinate system. It is a functional block diagram of the swing angle arithmetic unit which concerns on 2nd Embodiment of this invention. It is a block diagram of the skew runout angle detection value abnormality determination part in FIG. It is a block diagram of the skew runout angle estimation part in FIG. It is explanatory drawing of the main part of the runout angle detection apparatus described in Patent Document 1.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, FIG. 2 shows a main part of a crane to which the runout angle arithmetic unit according to this embodiment is applied.
In FIG. 2, 1 is a trolley, 2 is a garter in which the trolley 1 operates traversely, 5 is a hanging tool instructed by the trolley 1 via a rope (wire) 3 and a pulley 4, and 6 is integrally held by the hanging tool 5. The suspended load, 7 is a target arranged on the upper surface of the hanging tool 5, and 8 is a camera arranged on the lower surface of the trolley 1 to take an image of the target 7.

FIG. 3 is a plan view of the hanging tool 5, and corresponds to a captured image of the hanging tool 5 and the target 7 captured by the camera 8. Here, for example, one target 7 is arranged at substantially both ends of the hanger 5.
Since the suspension load 6 is integrally held by the suspension tool 5, the suspension tool 5 and the suspension load 6 are considered to be equivalent members as long as the runout angle is considered.

Next, the runout angle, which is the detection / estimation target in this embodiment, will be described.
The θ in FIG. 2 described above is a sway swing angle generated by the traversing motion of the trolley 1, and is an angle formed between the center of gravity of the suspended load 6 and the vertical axis X when the suspended load 6 swings. ..
Further, φ in FIG. 4 indicates a skew deflection angle formed by the suspension load 6 turning around the vertical axis X due to the center of gravity of the suspension load 6 being eccentric or the like. ..

Next, FIG. 5 is an explanatory diagram of a sway runout angle and a skew runout angle in the XYZ coordinate system. The XYZ coordinates shown in FIG. 5 are three-dimensional coordinates with the position of the camera 8 as the origin O, and E ₁ and E ₂ indicate the positions of the two targets 7 described above.

In FIG. 5, θ ₁ and θ ₂ are sway runout angles measured on the XOZ plane, and θ ₁ is the angle between the orthogonal projection axis and the X axis on the XOZ plane by 0-E ₁ , θ ₂ Is the angle between the orthogonal projection axis and the X axis on the XOZ plane according to 0-E ₂ .
Further, φ ₁ and φ ₂ are skew deflection angles measured on the XOY plane, φ ₁ is the angle between the orthogonal projection axis and the X axis on the XOY plane by 0-E ₁ , and φ ₂ is 0. It is the angle between the orthogonal projection axis and the X axis on the XOY plane according to −E ₂ .

To calculate the sway runout angle θ and the skew runout angle φ of the suspended load 6 using these angles, Equation 1 and Equation 2 are used.
[Formula 1] (Sway runout angle θ)
θ = (θ ₁ + θ ₂ ) / 2
[Formula 2] (skew runout angle φ)
φ = tan ^-1 [{tan (θ ₁ ) -tan (θ ₂ )} / {tan (φ ₁ ) -tan (φ ₂ )}]

Next, the runout angle arithmetic unit according to the first embodiment of the present invention will be described with reference to FIG. This first embodiment corresponds to the invention according to claim 1.
FIG. 1 is a functional block diagram of a runout angle arithmetic unit 10 realized by an arithmetic processing unit such as an industrial PLC (programmable logic controller). In the runout angle calculation device 10, 11 is a detection value abnormality determination unit, 12 is a runout angle estimation unit, 13 is a previous estimation value / angular velocity storage unit, and 10 is a runout angle calculation unit that calculates a sway runout angle and a skew runout angle. is there.

The operation of FIG. 1 will be described below.
The runout angle detection values θ ₁ , θ ₂ , φ ₁ , and φ ₂ detected based on the captured image of the target by the camera 8 in FIG. 2 are input to the runout angle calculation device 10 via a transmission means such as serial communication. .. In the swing angle arithmetic unit 10, the arithmetic is executed at a constant cycle.

The detected value abnormality determination unit 11 has the detected values θ ₁ , θ ₂ , φ ₁ , φ ₂ input this time, and the estimated value θ ₁ ', of the previous calculation cycle stored in the previous estimated value / angular velocity storage unit 13. _{θ 2 ', φ 1',} φ 2 ' and the comparison, respectively, if the deviation of each deflection angle exceeds a preset determination threshold value, abnormality determination is made for example normally logic "0" / The abnormality determination signal a is output. When the absolute value of the difference between the detected value and the estimated value of each runout angle is equal to or less than the above-mentioned determination threshold value, the determination signal a is determined to be normal and becomes a logic "1".
In this case, it is desirable that an abnormality is immediately determined when the deviation exceeds the determination threshold value, and a normal condition is determined when the state in which the deviation is equal to or less than the determination threshold value continues for a certain period of time.

When the logic of the normal / abnormality determination signal a is "1" and the detection value is determined to be normal, the runout angle estimation unit 12 sets the input detection values θ ₁ , θ ₂ , φ ₁ , and φ ₂ . it estimates _{θ 1 ', θ 2',} φ 1 ', φ 2' and outputs the (first process in claim 1).
If the logic of the normal / abnormality determination signal a is "0" and the detected value is determined to be abnormal, the previous estimated value θ ₁ ', θ stored in the previous estimated value / angular velocity storage unit 13 _{2 ', φ 1', φ} 2 ' from the previous angular velocity _{Δθ 1', Δθ 2 ',} Δφ 1', ' a value obtained by adding the estimated value of the current _{θ 1' Δφ 2, θ 2} ', φ 1' , Φ ₂ '(second process in claim 1).
In previous estimates, the angular velocity storage portion 13, the estimated value _{θ 1 ', θ 2',} φ 1 ', φ 2' saves the until the next operation, and obtains a difference between the previous estimate and the current estimate previous angular velocity _{Δθ 1 ', Δθ 2',} Δφ 1 ', Δφ 2' is calculated and stores them.

In deflection angle calculating section 10, the estimated value _{θ 1 ', θ 2',} φ 1 ', φ 2' a, ₁ theta in Equations 1 and 2 described above, theta _2, phi _1, by using as a phi _2, The sway runout angle θ and the skew runout angle φ are calculated and output.
The sway runout angle θ and the skew runout angle φ calculated by the above processing are used to generate a position command given to the actuator for performing so-called steady rest control.

If all the runout angle detection values θ ₁ , θ ₂ , φ ₁ , and φ ₂ momentarily become abnormal due to optical disturbance during target shooting, all of these values will be changed to the previous one. It may be estimated using the runout angle estimated value and the angular velocity. If any of the runout angle detection values θ ₁ , θ ₂ , φ ₁ , and φ ₂ becomes abnormal due to other reasons, the normal runout angle detection value is output as it is, and the abnormal runout angle is detected. The runout angle estimated value may be generated by performing the above-mentioned estimation process only on the value.

According to this first embodiment, it is not necessary to use a plurality of imaging devices as in Patent Document 2 described above, and even if a false detection of a runout angle or a detection error occurs temporarily, the runout is performed by arithmetic processing. The angle can be estimated appropriately and used for steady rest control.

Next, the runout angle arithmetic unit according to the second embodiment of the present invention will be described. This second embodiment corresponds to the invention according to claim 2.
In this embodiment, it is assumed that the steady rest control is performed by operating the actuator using the runout angle estimated value.

Next, FIG. 6 is a functional block diagram showing the runout angle calculation device 20 according to the second embodiment of the present invention together with the skew runout angle control unit 30. These runout angle calculation device 20 and skew runout angle control unit 30 can also be realized by a calculation processing device such as an industrial PLC.
Although the calculation and control of the skew runout angle will be described below, the calculation and control of the sway runout angle can also be applied.

In FIG. 6, the runout angle calculation device 20 includes a skew runout angle detection value abnormality determination unit 21 for determining normality / abnormality of the skew runout angle detection value φ, its output normal / abnormality determination signal a, and skew runout angle detection. A value φ and a skew runout angle estimation unit 22 for calculating a skew runout angle estimation value φ'by inputting an actuator position command (or an actuator position detection value) output from the skew runout angle control unit 30 are provided. There is.

Further, the skew runout angle control unit 30 generates an actuator position command using the skew runout angle estimated value φ'output from the skew runout angle estimation unit 22, and controls the operation of an actuator (not shown) to stop the shake. Take control. The skew swing angle control unit 30 is composed of, for example, a proportional integral differential (PID) control means.
As a specific method of steady rest control, for example, by controlling the position of the skew cylinder with an actuator, the lengths of a plurality of ropes (wires) that support the suspended load (hanging tool) at a plurality of locations are adjusted. A method for attenuating the skew runout angle is known, but the method is not particularly limited in the present invention.

FIG. 7 is a configuration diagram of the skew runout angle detection value abnormality determination unit 21 in FIG. The configuration and function of the abnormality determination unit 21 are substantially the same as the detection value abnormality determination unit 11 of FIG.
That is, in FIG. 7, the deviation between the skew runout angle detection value φ and the skew runout angle estimated value φ'is obtained by the subtraction means 21a, and the absolute value of the deviation is calculated by the absolute value calculation means 21b. This absolute value is input to the comparison means 21c together with the determination threshold value, and the output of the comparison means 21c is input to the on-delay means 21d to obtain a normal / abnormality determination signal a.

According to the above configuration, when the absolute value of the deviation exceeds the judgment threshold value, the logic of the normal / abnormality judgment signal a is immediately set to the abnormal side and output, and the state where the absolute value of the deviation is equal to or less than the judgment threshold value is set for a certain period of time. When it has passed, the logic of the normal / abnormal determination signal a is set to the normal side and output. However, at the start of the calculation, it is desirable that the normal / abnormal determination of the runout angle detection value is not performed only for the time until the runout angle estimated value follows the runout angle detection value.

Next, FIG. 8 shows the configuration of the skew runout angle estimation unit 22 in FIG. 6 together with the skew runout angle detection value abnormality determination unit 21.
The skew runout angle estimation unit 22 has first and second switching means 22a and 22b, subtraction means 22c, and addition means 22d that are switched by the normal / abnormality determination signal a from the skew runout angle detection value abnormality determination unit 21. , 22e, the first and second integrating means 22f, 22g, and the first to fourth proportional coefficients K ₁ , K ₂ , K ₃ , and K ₄ .

The operation of the skew deflection angle estimation unit 22 is as follows.
First, the relationship between the skew deflection angular velocity change rate with respect to the displacement of the actuator is acquired in advance, this ratio is set to the _first proportional coefficient K1, and the ratio of the skew deflection angular acceleration generated to the skew deflection angle is the first. The proportional coefficient K ₂ is set to ₂ , and the third and fourth proportional coefficients K ₃ and K ₄ are set for the difference between the skew runout angle detection value φ and the skew runout angle estimated value φ', respectively.

If normality / abnormality determination signal a is normal sets first, second switch means 22a, and 22b in the third, fourth proportional coefficient _K 3, _{K 4} side.
As a result, the skew runout angle estimated value and the second proportional coefficient K ₂ are obtained from the sum of the result of multiplying the actuator position command (or detected value) by the first proportional coefficient K ₁ and the output of the switching means 22a. The value obtained by subtracting the multiplication result is integrated by the first integrating means 22f to update the skew swing angle velocity estimated value. Further, the added value of the skewed angular velocity estimated value and the output of the switching means 22b is integrated by the second integrating means 22g to update the skewed angular velocity estimated value (first process in claim 2).
The third, the fourth proportional coefficient K _3, K ₄ be given on the basis of the state estimator design method, it is possible to obtain the skew swing angle estimate following the skew swing angle detection value.

When the normal / abnormal determination signal a is abnormal, the output signal from the subtraction means 22c is proportional to the third and fourth by switching the first and second switching means 22a and 22b to the "0" side. multiplication result will not be added and using a coefficient K _3, K _4.
That is, the actuator position command (or detection value) and the multiplication result of the first proportional coefficient K _1, the multiplication result, the deviation a first integral of the proportional coefficient K ₂ of the skew deflection angle estimated value and the second The skew swing angular velocity estimated value is updated by integrating with the means 22f, and further, the skew swing angular velocity estimated value is integrated as it is by the second integrating means 22g to update the skew swing angular velocity estimated value (second in claim 2). Processing).

That is, when the deflection angle detection value is abnormal, the multiplication result of the actuator position command (or a detected value) and the first coefficient of proportionality K _1, skew deflection angle estimated value and the second coefficient of proportionality K Only the skew motion model that feeds back the multiplication result with ₂ and updates the skew swing angular velocity estimated value and the skew swing angular velocity estimated value is configured.

As described above, according to the second embodiment, as in the first embodiment, the skew runout angle estimated value follows the skew runout angle detection value while the skew runout angle can be detected normally, so that the skew is skewed. It is possible to perform steady rest control by appropriately controlling the runout angle.
In addition, when an abnormality occurs in the skew runout angle detection value due to the influence of optical disturbance or the like, the skew runout angle estimated value is updated based on the skew motion model until the skew runout angle detection value returns to normal. .. Therefore, even if an abnormality occurs in the detected value for a period in which the change in the skew runout angle cannot be ignored, the estimated value can be updated to a skew runout angle close to the true value, and the skew runout angle control and thus the steady rest control can be performed. It can be continued without any trouble.

In the first and second embodiments described above, a means other than the image captured by the camera may be used as a means for acquiring the swing angle detection value of the suspended load.

INDUSTRIAL APPLICABILITY The present invention can be used as an arithmetic unit for skew runout angle and sway runout angle in the cargo handling field in which a suspended load is conveyed by a container crane or the like.

1: Trolley 2: Garter 3: Rope (wire)
4: Slider 5: Suspension tool 6: Suspended load 7: Target 8: Camera 10, 20: Runout angle calculation device 11: Detected value abnormality determination unit 12: Runout angle estimation unit 13: Previous estimated value / angular velocity storage unit 14: Runout Angular velocity calculation unit 21: Skew deflection angle detection value abnormality determination unit 21a: Subtraction means 21b: Absolute value calculation means 21c: Comparison means 21d: On-delay means 22: Skew deflection angle estimation units 22a, 22b: Switching means 22c: Subtraction means 22d , 22e: Addition means 22f, 22g: Integration means 30: Skew swing angle control unit

Claims (7)

In a runout angle arithmetic unit that generates a runout angle estimated value by calculating the runout angle detection value of a suspended load suspended from a traversing trolley at a predetermined cycle.
A detection value abnormality determination unit that determines normality / abnormality of the deflection angle detection value input to the runout angle calculation device,
The previous estimated value / angular velocity storage unit that calculates the runout angle velocity from the runout angle estimated value in the previous calculation cycle and saves the runout angle estimated value and the runout angle velocity,
When the detection value abnormality determination unit determines that it is normal, the first process of generating the runout angular velocity detection value as the current runout angular velocity estimation value is performed, and when the detection value abnormality determination unit determines that it is abnormal, the previous time. The runout angle estimation unit that performs the second processing to calculate the current runout angle estimation value based on the runout angle estimation value and the runout angle velocity of the previous calculation cycle saved in the estimated value / angular velocity storage unit.
Equipped with a,
The runout angle estimation unit
When there are a plurality of types of the runout angle detection values, the first processing is performed on the runout angle detection value determined to be normal by the detection value abnormality determination unit among the plurality of runout angle detection values, and A swing angle calculation device for a suspended load, characterized in that the second process is performed on the remaining runout angle detection value determined to be abnormal . A runout angle arithmetic unit that generates a runout angle estimated value by calculating the runout angle detection value of a suspended load suspended from a traversing trolley at a predetermined cycle, and the runout angle estimated value is used for steady rest control. In the runout angle arithmetic unit used to generate the actuator position command,
A detection value abnormality determination unit that determines normality / abnormality of the deflection angle detection value input to the runout angle calculation device,
When it is determined to be normal by the detection value abnormality determination unit, the runout angular velocity estimated value is obtained from the runout angle detection value, the actuator position command or the actuator position detection value, and the runout angle estimated value of the previous calculation cycle, and the runout is found. The first process of generating the current runout angle estimated value from the angular velocity estimated value and the runout angle detection value is performed, and when the detection value abnormality determination unit determines that the abnormality is found, the actuator position command or the actuator position detection value is used. And the deflection angle estimation unit that obtains the deflection angular velocity estimated value from the deflection angle estimated value of the previous calculation cycle and performs the second processing to generate the current deflection angular velocity estimated value from the said deflection angular velocity estimated value.
A swing angle arithmetic unit for suspended loads, which is characterized by being equipped with. In the swing angle calculation device for suspended loads according to claim 2 .
The runout angle estimation unit
When there are a plurality of types of the runout angle detection values, the first processing is performed on the runout angle detection value determined to be normal by the detection value abnormality determination unit among the plurality of runout angle detection values, and A swing angle calculation device for a suspended load, characterized in that the second process is performed on the remaining runout angle detection value determined to be abnormal. In the swing angle arithmetic unit of the suspended load according to any one of claims 1 to 3,
The detected value abnormality determination unit
A swing angle calculation device for a suspended load, characterized in that an abnormality is determined when the deviation between the input current runout detection value and the runout angle estimation value of the previous calculation cycle exceeds a predetermined determination threshold value. In the swing angle arithmetic unit of the suspended load according to claim 4,
The detected value abnormality determination unit
If the deviation between the input current runout detection value and the runout angle estimation value of the previous calculation cycle is equal to or less than the predetermined judgment threshold value for a certain period of time, it is determined to be normal, and the deviation is determined as described above. A swing angle arithmetic unit for suspended loads, which is characterized in that an abnormality is immediately determined when a threshold value is exceeded. In the swing angle calculation device for suspended loads according to any one of claims 1 to 5,
A swing angle arithmetic unit for a suspended load, wherein the runout angle detection value includes a skew runout angle detection value and a sway runout angle detection value. In the swing angle calculation device for suspended loads according to any one of claims 1 to 6,
A swing angle calculation device for a suspended load, characterized in that the runout angle detection value is obtained based on an image captured of a target that moves integrally with the suspended load.

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