JPS62244892A - Method of detecting angle of swing of hung load - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for detecting the swing angle of a suspended load, and more specifically, the swing angle of the suspended load with respect to the vertical line is obtained from the inclination angle of the suspension cable with respect to the boom. The present invention relates to a deflection angle detection method. This is used in the field of crane operation control to control the sway of a suspended load based on the sway angle of the suspended load.

[Prior art]

In order to prevent swinging of a suspended load during operation of a crane, etc., it is necessary to detect the swing angle of the suspended load. When detecting the swing angle of a suspended load, it has conventionally been done to detect the relative angle of a hanging cable with respect to a boom. Its detection can be easily measured using a known device such as a potentiometer. Then, using the detected inclination angle, the elevating and rotating operations of the boom are controlled to prevent the hanging load from swaying.

[Problem that the invention seeks to solve]

However, when the crane is installed on the hull of a ship, the angle of inclination of the hanging cable with respect to the boom is not the angle of inclination with respect to the vertical line. Therefore, if the relative angle with respect to the boom is used to control the steadiness of the crane, there is a problem that accurate steadiness control cannot be performed when the ship is tilted.

The present invention has been made in view of the above-mentioned problems, and its purpose is to provide a method for detecting the swing angle of a suspended load that can obtain the swing angle of a hanging cable with respect to a vertical line, which is required for crane sway control. It is to be.

[Means for solving problems]

The characteristics of the hanging load swing angle detection method of the present invention are as follows:
Described with reference to FIGS. 1(a) to (d), boom 1
In a crane that is equipped with a suspension cable 2 suspended from the tip of a boom 1 and is operated by lifting and supporting or suspending a load by the suspension cable 2, the crane body 5 is tilted in the elevation direction and the rotation direction with respect to the vertical line. The angles α and β, the elevation angle T of the boom 1 with respect to the crane body 5, and the inclination angle of the suspension cable 2 in the elevation direction and the turning direction with respect to the boom l! .

From Φ, the deflection angle θ1 of the suspended load in the elevation direction and turning direction with respect to the vertical line. The purpose is to obtain θ2.

〔Effect of the invention〕

According to the present invention as described above, even if the installation posture of the crane changes due to the rocking of the ship, the deflection angle θ1. θ2
Using this method, accurate sway control of the suspended load can be performed at all times, and stable automation of crane work is realized.

〔Example〕

FIG. 2 explains the configuration of an embodiment in which the method of the present invention is applied, and includes a boom 1 and a suspension rope 2 suspended from the tip of the boom 1, and the suspension rope 2 is used to lift and support a load. FIG. 2 is a schematic diagram of a crane 3 that is operated with a suspended load, and a swing angle detection device 4 for a suspended load attached thereto. The crane main body 5 is rotatably installed on a ship, for example, and has a boom 1 that supports a suspension cable 2 that can be raised and raised freely, and the suspension cable 2 is wound up and let out via a winch (not shown) to raise and lower a suspended load 6. The transfer is about to take place. The deflection angle detection device 4 includes a hanging cable tracking device 7, an imaged object 8, two cameras 9, and a deflection angle calculation device 10. In addition, if the center of gravity of the ship moves while loading and unloading suspended cargo between the ship's hull and the quay, or if the ship's attitude changes due to rocking due to wind and waves, the elevation angle of the boom l will immediately change to the elevation of the crane 3. Therefore, the behavior of the suspended load during movement will differ depending on the attitude of the ship.

The above-mentioned suspension cable tracking device 7 has two rotation axes. For example, when the suspension cable 2 swings in the vertical direction, it follows and rotates around the rotation axis 11, and when the suspension cable 2 swings in the turning direction, it rotates around the rotation axis 11. 12 and follows the movement of the hanging load 6 without inhibiting the movement of the hanging cable 2.

There is a sheave 13 on the upper end of the boom 1 that stretches the suspension cable 2, and an elevating arm 14 is attached coaxially with the sheave 13.
It swings in a vertical plane about the rotating shaft 11 in a nearly horizontal state. An auxiliary member 16 extending in a direction parallel to the rotating shaft 11 is integrally provided at the tip of the elevating arm 14.
A rotating shaft 12 is provided protrudingly at a position facing the cable groove of the sheave 13, and a rotating arm 17 is provided on the rotating shaft 12 so as to swing in a direction perpendicular to the elevation arm 14. Its rotating arm 1
At the lower end of 7, there is a guide body 18 that clamps the suspension cable 2 with two pairs of opposing rollers (not shown), which prevents the boom l due to swinging and elevation of the crane 3 and swinging of the suspension cable 2. The angle of inclination of the hanging cable 2 with respect to! , Φ [see FIGS. 1(b) and (d)], it follows the suspension cable 2. In this manner, in the suspension cable following device 7, the guide body 18 is moved while the elevating arm 14 and the rotating arm 17 are swinging.
always behaves together with the hanging rope 2 and changes its posture.

The imaged object 8 described above is the guide body 1 of the hanging cable tracking device 7.
8 and reflects or emits light. In this example, light sources such as light emitting diodes are used, and two light sources are provided at the upper and lower positions. These light sources8.8
Two cameras 9, 9 are fixed to the boom 1 so as to face the camera.

As shown in FIG. 3, the camera 9 has a built-in two-dimensional light spot position detector 19, and the lens 20 has a two-dimensional light spot position detector 19.
Light from the outside is collected on the light receiving surface 21 of the light source 8 to form an image of the light source 8. In FIG. 4, the two-dimensional light spot position detector 19 is, for example, a photodiode including two pairs of electrodes 22 to 25, and the two-dimensional light spot position detector 19 in the other camera 9 is also a two-dimensional light spot position detector 19. A photodiode including a set of electrodes 26-29.

Note that here, the imaging position Q+ of the two-dimensional light spot position detector 19
, Q2 are divided by the electrodes 22-25 and 26-29, respectively, to generate currents I11-114. Izt
~124 is output.

The deflection angle calculation device 10 includes two two-dimensional light spot position detectors 1.
3 of the light source 8 from the imaging position Ql, Q2 on the light receiving surface 21 of the light source 8
The dimensional position is calculated, and the inclination angle in the vertical direction of the suspension cable 2 with respect to the boom 1 is calculated from the 3D positioning device! and calculate the tilt angle Φ in the turning direction, and calculate the tilt angle! , Φ are used to calculate the deflection angle θ1 of the suspended load in the elevation direction with respect to the vertical direction, and the deflection angle θ2 in the turning direction, and is configured by, for example, a microcomputer. Output 111 of each electrode 22 to 25 described above
~114 are given to the processing circuit 30, and the coordinates (Xc+, Yc+) of the imaging position Q+ are expressed as: Xc1= (1++ =112) / CIn + I
tz)... (1) Ycsx (It Zoo I 14) /
(1+x+114)...(2). The calculation result is input to the calculation circuit 31. In the case of the other two-dimensional light spot position detector 19, an output current 121 w I 24 is outputted to the processing circuit 3o in a similar operation, and the output current 121 w I 24 is outputted to the two-dimensional light spot position detector 21 in accordance with this current value. A signal representing the coordinates (X C2, Y C2) of the imaging position Q2 of the incident light from the light source 8 is provided from the processing circuit 30 to the arithmetic circuit 31.

Here, a method for measuring and calculating the three-dimensional position of the light source 8 will be explained using FIG. A light source located at an arbitrary position on the hanging cable 2 is observed using two cameras. The coordinates of the light source P in the coordinate system fixed to the boom 1 [see Figure 2] are P (
Y, Z), and the imaging coordinates of point P in the camera coordinate system are Qt (Xc+, Yc+).

Q2 (XC2, YO2), boom 1 at point P
If a homogeneous coordinate system is used, the transformation from the coordinate system fixed at expressed.

Each element of the transformation matrices C+ and C2 is called a camera parameter, and assuming that CI and C2 are known, (X cs.

Yc+), (XC2, YO2) data, the points of interest are: 1, 1, Ia CI (1, 1) X+C+ (1, 2) Y+C+
(1,3) Z+C+ Q,4)-CI (3+l
) Xc+X-CI (3,2) Xc+Y-CI
(3,3) Xc+Z−CI (3,4) Xc
+-0・-1--αD CI (2,1) X+C+ (2,2) Y+C+
(2,3) Z+C+ (2,4)-CI (3+1
) Yc+X-CI (3,2) Yc'+Y-C
I C3*3 ) Yc +Z-C+ (3+4)
Yc+-0□ C+ (3,4) = 1
...“°(19Rs = (Xc+Yc
+・・XcnYcn) =・(
16) - Below Margin Find the three-dimensional position in the monolithic coordinate system. That is, Q,
F and V are expressed by equations (7), (8) and (9), respectively.
, F=QV, and the three-dimensional position of the point of interest can be determined more easily.

Each element of the camera parameters Ct and C2 is determined by the following procedure. Expanding equation (5) for one camera results in equations (11) and (12). Therefore, 12
In order to find these unknown quantities, it is sufficient to find the three-dimensional positions of six points that are not on the same plane and the corresponding positions in the camera image.
(14) (15) (16) then A*C
t = Rt holds true.

One camera parameter can be determined from .

Note that the same procedure may be performed for the other camera.

The swing angle of the suspended load is determined by the following procedure.

■ Install two light sources 8.8 at any position on the hanging rope tracking bag W7.
to be fixed.

■ The hanging cable 2 is suspended vertically and the three-dimensional positions of the two light sources 8°8 are measured. The result is LEDI (xs
, yt , z+ ) LED2 (xz, 3F2.zz
), then the direction vector a determined by the two light sources 8.8 is asIl(x+-x2.3z -yz, zt -22
) is given by

■ Measure the three-dimensional positions of the two light sources 8.8 when the suspended load swings, and calculate L ED 1 (X 1', y I',
z +') L E D 2 (X 2', y
2', 22'), the direction vector a' determined by the two light sources 8.8 is a'=CX(-X2', 3F1'-12', Z(-2
2').

■ The inclination angle θ of the suspended load at this time is: ■ If the inclination angle e is decomposed into the components of the elevation direction (y direction) and the turning direction (X direction), we get: Elevation direction! is, 11...(1B) However, V dew (Ft -yz, zt -22)v
'-(71'-y2', zs'-22')...(
19) However, ux (XI -X2, 21-22)u
-(XI'-X2', 21'-22').

Next, as shown in FIG. 1(a), in any initial state of the crane 3 in the elevation direction, when the suspended load 6 is hung vertically, the angle of inclination of the crane body 5 in the elevation direction with respect to the vertical direction is is α0, the elevation angle of the boom 1 with respect to the lane main body 5 is γ0, and the inclination angle of the suspension cable 2 in the elevation direction with respect to the boom 1 is A0. The above values are due to the fact that the ship is tilted for some reason or the crane body 5 has not returned to its original state, but in controlling the operation of the crane 3, it is necessary to take a certain state as a reference and change it from there. Since it is sufficient to be able to grasp the movement of , the above-mentioned state is taken as an example of an arbitrary state as the initial state. Figure 1(b) is a state diagram in which the deflection angle θ1 is taken in the elevation direction, and this θ1 is
The angle of inclination in the elevation direction of the crane body 5 with respect to the vertical direction is α, the elevation angle of the boom 1 with respect to the crane body 5 is T, and the inclination angle in the elevation direction of the suspension cable 2 with respect to the boom l is! This is the angle that occurs when . 01 is the angle of inclination determined through the above-mentioned suspension cable tracking device 7, etc.!
The deflection angle θ of the suspended load in the elevation direction is obtained using
1 is θ1=(α0-α)+(To-r)+
('Po-'P)--(22). Note that this calculation is also performed within the deflection angle calculation device 10 described above.

Fig. 1(c) is a schematic diagram of the initial state of the crane 3 in the turning direction, and Fig. 1(d) shows a state in which the crane 3 is at an angle of 1 angle θ2 in the turning direction! Figure 3. β0. β is the inclination angle of the crane body 5 in the turning direction with respect to the vertical direction, Φ0. Φ is the inclination angle of the suspension cable 2 in the turning direction with respect to the boom 1. The deflection angle θ2 of the hanging load in the turning direction is determined by θ2=(β0−β)−(Φ〇−Φ)−·−(23). Therefore, the inclination angle of the crane body 5 and the boom l
Even if the angle of elevation changes, the swing angle of the suspended load 6 relative to the vertical direction can be obtained. That is, the inclination angles α, α of the crane main body 5 in the elevation direction and the turning direction with respect to the vertical line
0. β, β0, the elevation angle γ of the boom 1 with respect to the crane body 5, and the inclination angle of the suspension cable 2 in the elevation direction and the turning direction with respect to the boom l! 1' From PolΦ and Φ0, the deflection angle θ1 of the suspended load 6 in the elevation direction and turning direction with respect to the vertical line. θ2 is obtained. This calculation is performed by the swing angle calculating device 10 described above, and the swing angle signal is input to a control device that drives and controls the crane 3. Hanging load 6
By performing steady control, stable automation of crane work is realized.

In addition, the above-mentioned inclination angle! and Φ are obtained from the three-dimensional position based on the two-dimensional light spot position by the deflection angle calculating device 10, the imaged object 8, and the camera 9.

Therefore, the angle of inclination! , Φ can be measured using a well-known potentiometer or the like, the angle signals obtained thereby can be used to obtain the swing angle in the elevation direction and rotation direction of the suspended load with respect to the vertical line. good.

[Brief explanation of drawings]

Figure 1 (a) is a schematic diagram of the initial state of the crane in the elevation direction, Figure 1 (b) is a state diagram with the swing angle in the elevation direction, and Figure 1 (C) is a schematic diagram of the crane device in the swing direction. A schematic diagram of the initial state, Figure 1 (d) is a state diagram showing a swing angle in the turning direction, and Figure 2 is a crane lifting and moving a load with a hanging rope, and detection of the swing angle of the suspended load attached to it. A schematic diagram of the device, Figure 3 is a perspective view of the camera, Figure 4 is a block diagram of the configuration of the deflection angle calculation device, and Figure 5 is a diagram of the principle of determining the three-dimensional position from the image formed by the two-dimensional light spot position detector. be. 1-boom, 2-suspension cable, 3-crane, 5-crane body, α, αo-angle of inclination in the elevation direction of the crane body with respect to the vertical line, β, βo-angle of inclination of the crane body in the direction of rotation with respect to the vertical line , r - Elevation angle of the boom with respect to the crane body, V, VO - - Angle of inclination of the suspension cable in the elevation direction with respect to the boom, Φ. Φ0-・Inclination angle of the suspension cable in the turning direction with respect to the boom, θ
1.- Swing angle of the suspended load in the elevation direction with respect to the vertical line, 02-
- Swing angle in the swing direction of the suspended load with respect to the vertical line. Patent distributor Kawasaki Heavy Industries, Ltd. Agent Patent attorney Katsutoshi Yoshimura (and one other person) Figure 1 (a) Figure 174 (b) Figure 1 (C) Figure 1 (d) M2 Figure Z Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] (1) In a crane that is equipped with a boom and a suspension cable suspended from the tip of the boom and is operated by lifting and supporting or suspending a load, the crane body is tilted in the vertical direction and in the rotation direction with respect to the vertical line. The swing angle in the elevation and rotation direction of the suspended load with respect to the vertical line is obtained from the angle, the elevation angle of the boom with respect to the crane body, and the inclination angle of the suspension cable in the elevation and rotation direction with respect to the boom. Method for detecting the swing angle of a suspended load.