JPH0780671B2 - Deflection angle detector for suspended load - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a swing angle detection device for a suspended load, and more specifically, a swing angle with respect to a vertical direction of a suspended load from an inclination angle of a hanging rope with respect to a support body. The present invention relates to a deflection angle detecting device that can be obtained. This is used in the field of operation control of a crane that performs vibration control of a suspended load from the deflection angle of the suspended load.

[Prior art]

In order to prevent the swing of the suspended load during operation of a crane, it is necessary to detect the swing angle of the suspended load. A well-known inclinometer is one that has been conventionally adopted to detect the deflection angle. It has a mechanical structure in which oil is sealed in order to improve damping, and the slant angle of the suspended rope can be accurately detected when the suspended load is stationary. Unlike such a detector, a light source is attached to the suspended load and the light source is observed from directly above the suspended load with a two-dimensional image pickup tube to detect the deflection angle of the suspended load or suspended rope. For example, it is described in JP-A-54-157953. According to this type of detecting device, the swing of the suspended load or the suspended rope can be detected in a non-contact manner, and the detection signal can be immediately input to the computer to simplify the control of the crane. it can.

[Problems to be solved by the invention]

Since the above-described inclinometer has a mechanical structure, it has a slow response speed in the case of acceleration, and further, since oil for damping is enclosed, temperature correction is required. On the other hand, in the case of detecting the deflection angle of a suspended load or suspended rope by observing the light source with a two-dimensional image pickup tube, the image pickup tube must always be located directly above the suspended load. , The mounting position of the image pickup tube and the light source is limited. Depending on the crane, the installation space may be limited and installation may be difficult.

The present invention has been made in view of the above problems, and an object thereof is to be able to install an image pickup tube and an image pickup object at arbitrary positions, to detect the inclination angle of a hanging rope without contact, at high speed, and with high accuracy. It is an object of the present invention to provide a swing angle detection device for a suspended load, which can obtain the swing angle of the suspended load based on the above.

[Means for solving problems]

Where the features of the swing angle detection device of the suspended load of the present invention,
Referring to FIG. 1, in a crane device 2 that operates by suspending and supporting or suspending a load with a suspension rope 1, a suspension rope tracking means 7 that behaves following the movement of the suspension rope 1. An object to be imaged 8 that is attached to the hanging rope tracking means 7 and reflects or emits light, and a two-dimensional light spot position detector 21 [see FIG. 3] fixed to the support 5 of the hanging rope 1 are built in. The three-dimensional position of the object 8 is calculated from the two cameras 9 and the imaging positions on the light-receiving surfaces 23 (see FIG. 3) of the two two-dimensional light spot position detectors 21 and the three-dimensional positions thereof are calculated. The tilt angles Ψ and Φ of the suspension rope 1 with respect to the support 5 are calculated from the tilt angles, and the tilt angles are used to calculate the tilt angles θ ₁ and θ ₂ of the suspended load 6 in the vertical direction and the turning direction with respect to the vertical direction. The calculation means 10 is provided.

[Action]

Since the hanging rope tracking means 7 follows the movement of the hanging rope without interfering with the movement of the hanging rope 1, the image-captured object 8 attached thereto moves with the swing of the hanging load 6. Two cameras 9 having a two-dimensional light spot position detector 21 fixed to a support 5 supported by the hanging rope 1 observe the imaged object 8 and receive light from each two-dimensional light spot position detector 21. From the image formation position on the surface 23, the shake angle calculation means 10 calculates the three-dimensional position of the imaged body 8. From the position, the inclination angles Ψ and Φ of the hanging rope 1 with respect to the support 5 are calculated, and the deflection angles θ ₁ and θ ₂ of the suspended load 6 in the elevation direction and the turning direction with respect to the vertical direction are calculated. Therefore, the tilt angle of the suspended load with respect to the support can be detected optically without contact, and the suspended object can be shaken by the two-dimensional light spot position detector and the microcomputer by setting the imaged object and the camera at arbitrary positions. By calculating the angle, the swing angle of the suspended load can be obtained with high accuracy.

〔The invention's effect〕

According to the configuration of the present invention as described above, since the hanging rope tracking means and the optical observing means are used, the swing angle of the suspended load can be detected in a non-contact manner without giving a disturbance to the hanging rope. Since the imaged object and the camera can be installed at arbitrary positions and measured,
Unlike conventional optical detectors, there are no restrictions on the type of crane or mounting position, and there is no need to mount the crane directly above a suspended load with high accuracy. Fast response speed 2
The deflection angle of the suspended load can be detected at high speed by the high-speed calculation by the dimensional light spot position detector and the microcomputer. By improving the detection accuracy of the two-dimensional light spot position detector, it becomes possible to detect the swing angle of the suspended load with high accuracy. By utilizing the swing angle output signal, swing load control can be performed, and stable automation of crane work can be realized.

〔Example〕

FIG. 1 illustrates a configuration of an embodiment of the present invention, in which a crane device 2 that lifts and supports or suspends a load by a hanging rope 1 and a swing angle detection device 3 of a suspended load attached to the crane device 2. FIG. The crane body 4 is installed, for example, on the ship so as to be rotatable, and a support body 5 called a boom or a jib that supports the hanging rope 1 is provided so as to be raised and lowered.
The suspended rope 1 is rolled up and unwound via a winch (not shown) to lift and lower the suspended load 6. The shake angle detection device 3 includes a hanging rope tracking means 7, an imaged object 8, two cameras 9, and a shake angle calculation means 10. If the center of gravity of the hull moves while loading and unloading the suspended load between the hull and the quay, or if the hull oscillates due to wind waves and its posture changes, the elevation angle of the support immediately increases. The angle of elevation will no longer be obtained, and the behavior of the suspended load during movement will differ depending on the attitude of the hull.

The above-mentioned hanging rope tracking means 7 has two rotation axes. For example, when the hanging rope 1 swings in the elevation direction, the hanging rope follows and rotates about the rotation axis 11, and when the hanging rope 1 swings in the turning direction, the rotation axis moves. It rotates around 12 and rotates the suspended load 6 without hindering the movement of the suspended rope 1.
Follow the movement of. In more detail, hanging rope 1
The device shown in FIGS. 2 (a) to 2 (d) is provided on the upper part of the support body 5 for suspending. At the upper end of the support body 5, the suspended rope 1
There is a sheave 13 (see Fig. 1) that stretches the shaft, and the elevation arm 14 is attached coaxially with it, and it is vertical to the rotating shaft 11 with the counterweight 15 being almost horizontal without losing the balance. It swings in the plane. That supine arm
At the tip of 14 is an auxiliary member extending in a direction parallel to the rotation axis 11.
16 is integrally provided, a rotary shaft 12 is projectingly provided at a position facing the rope groove of the sheave 13, and a swing arm 17 is provided so as to swing in a direction perpendicular to the elevation arm 14. At the lower end of the revolving arm 17, there are two pairs of rollers 1 facing each other.
There is a guide body 20 that holds the suspended rope 1 with 8, 19 and it is
The tilt angles Ψ and Φ of the suspension rope 1 with respect to the support 5 due to the turning of the crane device 2 and the elevation and swing of the suspension rope 1 [7th
(See Figures (b) and (d)]
To follow. In this way, in the hanging rope tracking means 7,
While the elevation arm 14 and the swing arm 17 swing, the guide body 20 always moves together with the hanging rope 1 to change its posture.

The above-mentioned imaged body 8 is the guide body 20 of the hanging rope tracking means 7.
It is attached to and reflects or emits light. In this example, a light source such as a light emitting diode is adopted, and two light sources are provided at upper and lower positions. It should be noted that the number of light sources may be one, but depending on the calculation form, two light sources may be required, and this may differ depending on the configuration of the device. These light sources 8,8
Two cameras 9 and 9 are fixed to the support 5 so as to face the camera. As shown in FIG. 3, the camera 9 has a built-in two-dimensional light spot position detector 21, and the lens 2 collects light from the outside on the light-receiving surface 23 of the two-dimensional light spot position detector 21 to generate a light source 8. Image. In FIG. 4, the two-dimensional light spot position detector 21 is, for example, a photodiode including two pairs of electrodes 24 to 27, and the two-dimensional light spot position detector 21 in the other camera 9 has the same structure. A photodiode including a set of electrodes 28-31. The current generated by the incident light from the light source 8 focused on the image forming positions Q ₁ and Q ₂ of the two-dimensional light spot position detector 21 is
Are each divided by the electrodes 24 to 27 and 28 to 31, is outputted as a current _{I 11 ~I 14, I 21 ~I} 24 respectively.

The deflection angle calculation means 10 detects the three-dimensional position of the light source 8 from the image forming positions Q ₁ and Q ₂ on the light receiving surface 23 of the two two-dimensional light spot position detectors 21, and detects the support 5 from the three-dimensional position. Hanging rope against
The tilt angle Ψ of the vertical direction and the tilt angle Φ of the turning direction are calculated, and the tilt angle Ψ and Φ are used to calculate the swing angle θ ₁ of the suspended load in the vertical direction and the swing angle θ ₂ of the turning direction with respect to the vertical direction. For example, it is composed of a microcomputer. The outputs I _{11 to} I ₁₄ of the electrodes 24 to 27 described above are given to the processing circuit 32, and the coordinates (X _C1 , Y _C1 ) of the image forming position Q are X _C1 = [I ₁₁ -I ₁₂ ] / [ I ₁₁ + I ₁₂ ] ... (1) Y _C1 = [I ₁₃ -I ₁₄ ] / [I ₁₃ + I ₁₄ ] ... (2) The calculation result is input to the calculation circuit 33. Also in the case of the other two-dimensional light spot position detector 21, the output currents I _{21 to} I ₂₄ are similarly operated.
Is output to the processing circuit 32, and a signal representing the coordinates (X _C2 , Y _C2 ) of the image forming position Q ₂ of the incident light from the light source 8 incident on the two-dimensional light spot position detector 21 corresponding to this current value. But the processing circuit 32
Given to the arithmetic circuit 33.

Here, a method for measuring and calculating the three-dimensional position of the light source 8 will be described with reference to FIG. The light source at an arbitrary position of the hanging rope 1 is observed by two cameras. The coordinate of the light source P in the coordinate system fixed to the support 5 [see FIG. 1] is P (X, Y,
Z), the image forming coordinate of the point P in the camera coordinate system is Q ₁ (X _C1 , Y
_C1 ), Q ₂ (X _C2 , Y _C2 ), the coordinate system fixed to the support 5 at the point P can be converted to the camera coordinate system by using the homogeneous coordinate systems (3), (4) ) Transformation matrix Is expressed by equations (5) and (6). Its transformation matrix Each element of is called a camera parameter, Is known, (X _C1 , C ₁ (1,1) X + C ₁ (1,2) Y + C ₁ (1,3) Z + C ₁ (1,4) -C ₁ (3,1) X _C1 XC
₁ (3,2) X _C1 YC ₁ (3,3) X _C1 ZC ₁ (3,4) X _C1 = 0 …… (11) C ₁ (2,1) X + C ₁ (2,2) Y + C ₁ (2,3) Z + C ₁ (2,4) -C ₁ (3,1) Y _C1 XC
₁ (3,2) Y _C1 YC ₁ (3,3) Y _C1 ZC ₁ (3,4) Y _C1 = 0 …… (12) C ₁ = (C ₁ (1,1) C ₁ (1,2) C ₁ (1,3) C ₁ (1,4) C ₁ (2,1) C ₁ (2,2) C
₁ (2,3) C ₁ (2,4) C ₁ (3,1) C ₁ (3,2) C ₁ (3,3)] ^t …… (14) C ₁ (3,4) = 1 …… (15) R ₁ = [X _C1 Y _C1 …… X _Cn Y _Cn ] …… (16) Y _C1 ), (X _C2 , Y _C2 ) From the data of 3D position in the object coordinate system Ask. That, Q, formula F, V, respectively (7), placing a (8) and (9), is expressed as F = QV, 3-dimensional position of the target ^{point, V = (Q t Q)} -1 Q ^t F ・ ・ ・ (10)

Camera parameters Each element of is obtained by the following procedure. When formula (5) is expanded for one camera, formulas (11) and (12) are obtained. Therefore, in order to obtain twelve unknowns, six three-dimensional positions not on the same plane and corresponding positions in the camera image may be obtained. In addition, in order to improve the accuracy of the parameter, it is only necessary to measure six or more points and determine the parameter by the least square method. Now, use A ₁ C ₁ R ₁ as the formula (13).
If you write (14) (15) (16), A ₁ C ₁ = R ₁ .

_One camera parameter can be determined from C ₁ = (A ₁ ^t A ₁ ) ^-1 A ₁ ^t R ₁ (17).
It should be noted that the same may be done for the other camera.

The deflection angle of the suspended load is calculated by the following procedure.

[I] When using two light sources Two light sources 8 and 8 are fixed at arbitrary positions of the suspended rope following means 7.

The hanging rope 2 is hung vertically and the two light sources 8 and 3
Measure the dimensional position. If the result is LED1 (x ₁ , y ₁ , z ₁ ) LED2 (x ₂ , y ₂ , z ₂ ), the direction vector determined by the two light sources 8 and 8 is = (x ₁ -x ₂ , y It is given by ₁ -y ₂ , z ₁ -z ₂ ).

The three-dimensional position of the two light sources 8 and 8 when the suspended load is shaken is measured, and LED1 (x ₁ ′, y ₁ ′, z ₁ ′) LED2 (x ₂ ′, y ₂ ′, z ₂ ′) Then, the direction vector ′ determined by the two light sources 8,8
Is given by ′ = (x ₁ ′ −x ₂ ′, y ₁ ′ −y ₂ ′, z ₁ ′ −z ₂ ′).

The inclination angle Θ of the suspended load at this time is Θ = cos ^-1 [(・ ') / (||) ・ (|'
｜)] Decomposing the tilt angle Θ into components in the elevation direction (y direction) and the turning direction (x direction), the elevation direction Ψ is Ψ = cos ^-1 [(・ ') ・ (|｜ ・ ｜' |) ] ...
(18) However, = (y ₁ -y ₂ , z ₁ -z ₂ ) ′ = (y ₁ ′ −y ₂ ′, z ₁ ′ −z ₂ ′) The turning direction Φ is Φ = cos ⁻¹ [ (・ '/ (|||||)] ……
(19) However, it can be obtained by = (x ₁ -x ₂ , z ₁ -z ₂ ) ′ = (x ₁ ′ −x ₂ ′, z ₁ ′ −z ₂ ′).

[Ii] When using one light source With reference to FIG. 6, one light source 8 is fixed at an arbitrary position of the suspended rope following means 7.

The hanging rope 1 is hung vertically and the three-dimensional position of the light source 8 is measured, and this position is set to (0,0,0).

When the three-dimensional position of the light source 8 when the suspended load 6 swings is measured and the amount of change from the above position (0,0,0) is (X, Y, Z), the inclination angle Θ of the suspended load is The elevation direction Ψ is Ψ = cos ^-1 [1- {Y ² + Z ² } / 2 (l ² + (r-δ) ² }] ...... (20) The turning direction Φ is Φ = sin ^-1 ( X / l) (21) where r is the radius of the sheave 13 δ is the offset position of the light source 8 from the hanging rope 1 l is the length from the center of the sheave 13 to the light source 8 along the hanging rope 1 As described above, the calculation form is slightly different depending on whether the number of light sources is one or two, but the inclination angle Ψ in the elevation direction and the inclination angle Φ in the turning direction of the hanging rope 1 with respect to the support 5 are calculated as described above. Be done.

Next, as shown in FIG. 7 (a), in an arbitrary initial state in the elevation direction of the crane device 2, when the suspended load 6 is hung vertically, the inclination of the crane body 4 in the elevation direction with respect to the vertical direction. The angle is α ₀ , the depression angle of the support 5 with respect to the crane support 4 is γ ₀ , and the inclination angle of the suspension rope 1 with respect to the support 5 in the depression direction is Ψ ₀ . It should be noted that the above values are because the hull is tilted for some reason or the crane body 5 has not returned to its original state. Since it is sufficient to understand the movement from the above, the above-mentioned state is set as an initial state as an example of an arbitrary state. FIG. 7 (b) is a state diagram in which the deflection angle θ ₁ is taken in the elevation direction,
For this θ ₁ , the inclination angle of the crane body 4 in the elevation direction with respect to the vertical direction is α, the elevation angle of the support 5 with respect to the crane body 4 is γ, and the inclination angle of the suspension rope 1 with respect to the support 5 in the elevation direction is Ψ. Is the angle that occurs when The θ ₁ is obtained by using the inclination angles Ψ ₀ and Ψ obtained through the above-mentioned hanging rope tracking means 7 and the like, and the deflection angle θ ₁ of the suspended load in the elevation direction is θ ₁ = (α ₀ −α) + (γ ₀ −γ) +
(Ψ ₀ −Ψ) ・ ・ ・ (22). It should be noted that this calculation is also performed in the deflection angle calculating means 10 described above.

FIG. 7 (c) is a schematic view of the initial state of the crane device 2 in the turning direction, and FIG. 7 (d) is a deflection angle θ _{2 in the} turning direction.
It is the state diagram which is taking. β ₀ and β are tilt angles of the crane body 4 in the turning direction with respect to the vertical direction, and Φ ₀ and Φ are tilt angles of the hanging rope 1 with respect to the support 5 in the turning direction. Then, the swing angle θ ₂ of the suspended load in the turning direction is obtained by θ ₂ = (β ₀ −β) − (Φ ₀ −Φ) (23). Therefore, even if the inclination angle of the crane main body 4 and the depression angle of the support body 5 change, the deflection angle of the suspended load with respect to the vertical direction can be obtained. This calculation is also performed by the deflection angle calculating means 10 described above, and the deflection angle signal is input to the control device that drives and controls the crane device 2 so that the swing load can be controlled to stabilize the crane work. Automation is realized.

According to such a device, since the optical means is used, it is possible to perform non-contact measurement without adding a disturbance to the hanging rope, and further, since the light source and the camera can be installed at arbitrary positions, As with the optical detector of (1), there is no need for the trouble of precisely installing the device at a limited position, for example, directly above the suspended load. As a result, it can be applied to all types of cranes that suspend loads with hanging ropes, regardless of types such as overhead cranes and deck cranes. In addition, the deflection angle of the suspended load can be detected at high speed by the high-speed calculation by the two-dimensional light spot position detector having a fast response speed and the microcomputer. If the detection accuracy of the two-dimensional light spot position detector is improved, the swing angle of the suspended load can be detected with high accuracy.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram of a crane device for hoisting and moving a load by a hanging rope, and a swing angle detection device of a hanging load attached to the crane device. FIG. A front view of the means, FIG. 2 (b) is a plan view thereof, and FIG. 2 (c) is II-I of FIG.
FIG. 2 (d) is a view taken along the line III-III in FIG. 2 (a), FIG. 3 is a perspective view of the camera, and FIG. FIG. 5 is a principle diagram for obtaining a three-dimensional position from an image formed by a two-dimensional light spot position detector, FIG. 6 is an explanatory diagram of behavior of the hanging rope tracking means when there is one light source, and FIG. 7 (a) is a crane. Fig. 7 (b) is a schematic diagram of the initial state in the elevation direction of the device, Fig. 7 (b) is a state diagram in which the deflection angle is taken in the elevation direction, and Fig. 7 (c) is a schematic diagram of the initial state in the turning direction of the crane device. FIG. 7D is a state diagram in which the deflection angle is taken in the turning direction. 1 ... Hanging rope, 2 ... Crane device, 5 ... Support, 6
…… Suspended load, 7 …… Suspended line tracking means, 8 …… Image to be picked up (light source), 9 …… Camera, 10 …… Deflection angle calculation means, 13 …… Sheave, 14 …… Depression arm, 17… … Swivel arm, 20 …… guide body, 21 …… two-dimensional light spot position detector, 23 …… light receiving surface,
Ψ, Φ …… Inclination angle, θ ₁ , θ ₂ …… Deflection angle.

 ─────────────────────────────────────────────────── --- Continuation of the front page (72) Inventor Norihide Komatsu No. 234 Matsumoto, Higashiya-cho, Nishi-ku, Kobe City, Hyogo Prefecture Kawasaki Heavy Industries, Ltd. Nishi-Kobe Plant (56) Reference JP-A-61-126413 (JP, A) JP-A-60-213693 (JP, A)

Claims (2)

[Claims] 1. A crane apparatus for operating a load by suspending and supporting or suspending a load by a hanging rope, and a hanging rope following means that behaves following the movement of the hanging rope, and attached to this hanging rope following means. Image pickup object that reflects or emits light, two cameras that are fixed to the support of the hanging rope and have a built-in two-dimensional light spot position detector, and light-receiving surfaces of the two two-dimensional light spot position detectors. The three-dimensional position of the object to be imaged is calculated from the image forming position above, the tilt angle of the hanging rope with respect to the support is calculated from the three-dimensional position, and the tilt angle is used to determine the vertical direction of the suspended load relative to the vertical direction. And a swing angle calculation device for calculating a swing angle in the turning direction. 2. The hanging rope following means is attached to the elevation arm coaxial with a sheave for suspending the hanging rope, a swing arm attached to the elevation arm and rotatable in a swing direction, and the swing arm. The swing angle detection device for a suspended load according to claim 1, further comprising: a guide body that holds the hanging rope.