JPH10258987A - Anti-swinging device for slung load - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate a phase lag and shorten damping time of swing when rocking vibration of a slung load is removed in an anti-swinging device for lifted load, such as a container crane. SOLUTION: A notch command signal 12 from a control panel 10, a swing displacement detection signal 13 from a camera 8, a trolley position and speed detection signals 14, 15 from a trolley driving device 5 are inputted respectively to a controller 110, and respective data of the notch command, trolley speed, trolley position are inputted to a control computing part 20 as numeric data formed at an A/D conversion part 17. The swing displacement data are inputted into the control computing part 20 by eliminating its rocking swing element at a rocking swing command processing part 18. By calculating a trolley speed command at the control computing part 20, forming it into a trolley speed command signal 16 of an analog signal with the D/A conversion part 21, and outputting it to the trolley driving device 5, it is possible to eliminate a phase lag, and shorten damping time for stopping swing of the slung load.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steady rest device for a suspended load, and is mainly applied to a steady rest of a suspended load such as a container crane.

[0002]

2. Description of the Related Art FIG. 7 is a schematic structural view of a device for preventing a suspended load in a conventional container crane. In the figure, 1 is a crane, 2 is a trolley that traverses (moves in the left-right direction in the figure) on the crane 3, 3 is a suspended load, 4 is a hanging rope of the suspended load 3, 5 is a trolley drive device, and 6 is a trolley 2 Is a driving rope for driving the motor. Reference numeral 7 denotes a machine room in which a control device 11 is installed.

In the above configuration, first, the deflection of the suspended load 3 will be described. In the case where the trolley 2 is traversed from left to right in the state of FIG. 7, when the trolley 2 is first accelerated, the suspended load 3 swings to the rear on the left side of the figure due to inertial force. Then, when the trolley 2 is decelerated after moving for a certain distance, the suspended load swings forward due to the inertial force on the right side in the figure.

Next, detection of a signal for steadying will be described. Mark 9 on the hanging tool
Is detected by the camera 8 attached to the bottom surface of the trolley 2 and detected as a shake displacement detection signal 13. The position and speed of the trolley 2 are detected by a position detector and a speed detector attached to the trolley drive device 5, and output as a trolley position detection signal 14 and a trolley speed detection signal 15. Further, a trolley target speed setting (notch command) operated by the operator is detected from the operation panel 10 and is set as a notch command signal 12. Each of the above signals 12, 13, 14, 1
5 are taken into the control device 11 and the trolley 2
To control the steady rest.

FIG. 8 is an overall system configuration diagram of the above-mentioned steady rest device. In the figure, a notch command signal 12 is output from an operation panel 10 and a shake displacement detection signal 13 is output from a camera 8.
However, the trolley driving device 5 outputs a trolley position detection signal 1
4. The trolley speed detection signal 15 is transmitted to the controller 11
Is input to

In the control device 11, the input signals are converted into numerical data by the A / D converter 17, and the notch command, the trolley speed and the trolley position are directly input to the control operation unit 20. You. High-frequency noise is removed from the vibration displacement data by the low-pass filter 22, and the data is differentiated by the differential operation unit 19, and these are input to the control operation unit 20. The control operation unit 20 calculates a trolley speed command based on each of these data, converts the trolley speed command into an analog signal at the D / A conversion unit 21, and commands the trolley driving device 5 as the trolley speed command signal 16 to control the trolley 2. Then, the suspension of the suspended load 3 is performed.

[0007]

The suspended load 3 by the trolley is accelerated and decelerated when the trolley is traversed as shown in FIG.
As shown in (a), a swinging motion occurs. This movement is a pendulum movement due to the mass of the hanging rope 4 and the hanging load 3.
However, when the trolley arrives at the target position and the inching is repeated at the minute positioning, the rocking vibration shown in FIG. The rocking vibration is a high-frequency rotational movement around the axis from the front to the back of the drawing due to the spring force due to the expansion and contraction of the hanging rope 4 and the moment of inertia of the suspended load 3. Since this rocking vibration is not a vibration of the suspended load 3, it is not desired to detect it as a vibration displacement.
Since the position of the mark 9 is displaced as shown in FIG.

On the other hand, the anti-sway control is a control for giving a damping to a normal oscillating motion, and a spillover phenomenon occurs in which an unexpected high-frequency vibration is caused to vibrate. Therefore, a low-pass filter 22 that cuts the high-frequency vibration is applied to the shake displacement signal. However, the low-pass filter 22 causes a phase delay with respect to the actual shake displacement detection, and it takes time to attenuate the shake. Performance degradation.

Accordingly, an object of the present invention is to eliminate the adverse effect of a phase delay caused by a conventionally used low-pass filter in a steady rest device for a suspended load. Shorten it,
Another object of the present invention is to provide a control calculation function that can shorten the cargo handling time.

[0010]

The present invention provides the following means for solving the above-mentioned problems.

[0011] A target speed setting signal of a trolley that hangs a suspended load with a rope and conveys the trolley, a position and speed signal of the trolley, and a swing signal of the suspended load are input, respectively.
High-frequency vibration noise is removed from the vibration signal, a signal from which the high-frequency vibration noise is removed, a target speed setting signal, a trolley speed command is calculated and output based on the position and speed signals, and the trolley speed command is used to output the trolley speed command. In a steadying device for a suspended load for controlling the swing of a suspended load, the high frequency vibration elimination is performed by a rocking vibration elimination processing means.

According to the present invention, instead of a conventional low-pass filter, a locking vibration elimination processing means described below, which does not give a phase delay to an actual shake displacement, is applied. FIG. 3 is a block diagram of the locking vibration removal processing of the present invention.
FIG. 4 shows a bandpass filter applied to this processing.
Description will be made based on these drawings.

(1) First, 11 kinds of band-pass filters shown in FIG. 4 are applied to the swing detection signal of the suspended load. The transfer function of the bandpass filter is, for example, 2ζ
Ω / (s ² + 2 · ζ · ω · s + ω ² ), and ζ = 0.0
1, ω / (2π) = 0.4 to 0.6 Hz.

(2) For each bandpass filter output signal, a MAX value is detected for the past N seconds to obtain a vibration amplitude value.

(3) Select a band-pass filter having the largest vibration amplitude value and the next largest band-pass filter. For example, when the locking natural frequency is 0.505
In the case of Hz, the band-pass filters 6 and 7 are selected as shown by circles in FIG. Than this,
It can be seen that the natural frequency is between 0.5 and 0.52 Hz, and since the 0.5 Hz side is large, the natural frequency is 0.5 to 0.52 Hz.
Limited to 0.51 Hz.

(4) Eleven types of bandpass filters divided into ten within a limited frequency range are generated, and a shake detection signal is input to each bandpass filter. The bandpass filter at this time is also the same as the equation shown in (1). However,
ω / (2π) is, for example, 1 between 0.5 and 0.51 Hz.
It is divided into zero.

(5) For each bandpass filter output signal, a MAX value is detected in the past N seconds to obtain a vibration amplitude value.

(6) A band-pass filter having a maximum vibration amplitude value is selected, and the natural frequency of the band-pass filter is defined as a rocking frequency.

(7) A method for removing the rocking frequency
Generate a switch filter. Notch filter transfer function
Is, for example, (s^Two+ Ω^Two) / (S^Two+ 2.5ζ ・ ω ・
s + ω ^Two), Ζ = 0.01, ω / (2π) = rockin
Frequency.

A shake detection signal is input to this, and a shake detection signal from which rocking vibration has been removed is obtained. For example, if the rocking frequency is 0.5 Hz, a notch filter shown in FIG. 5 is generated. By inputting a shake detection signal to this, 100% of the rocking vibration is theoretically removed.

FIG. 6 shows the gain characteristics and phase characteristics of the present notch filter. The vibration frequency is 0.2 Hz or less, and the conventional low-pass filter has a phase delay effect, whereas the notch filter has a phase delay of 0 and has no effect on the vibration displacement detection.

Therefore, due to the phase delay of the shake displacement detection,
It does not take much time for the vibration to attenuate, resulting in high-performance vibration control.

[0023]

Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is an overall configuration diagram of a suspended load steadying device according to an embodiment of the present invention. In FIG. 1, the configuration of the device is the same as the conventional one,
The control device is replaced by 110, and the low-pass filter 22 in the conventional control device 11 is replaced with a locking vibration removal processing unit 18 described later with reference to FIG.

In FIG. 1, first, with respect to the swing of the suspended load 3, the displacement of the swing is detected by capturing the mark 9 on the hanging tool with the camera 8 attached to the bottom surface of the trolley 2. The position and speed of the trolley 2 are detected by a position detector and a speed detector attached to the trolley drive device 5. The trolley target speed setting (notch command) operated by the operator is detected from the operation panel 10.

These detections are the same as in the prior art, and the detected four signals of the notch command signal 12, the shake displacement detection signal 13, the trolley position detection signal 14, and the trolley speed detection signal 15 are input to the control device 110. Then, the anti-sway control process is performed.

FIG. 2 is an overall system diagram of the suspension device for hanging a load shown in FIG. 1, wherein a notch command signal 12 from an operation panel 10, a shake displacement detection signal 13 from a camera 8 and a trolley. A trolley position detection signal 14 and a trolley speed detection signal 15 are input to the control device 110 from the drive device 5.

The control device 110 inputs each of these input signals to the A / D converter 17 and converts the analog signals into numerical data. The notch command, the trolley speed, and the trolley position among the numerical data thus obtained are directly input to the control arithmetic processing unit 20. The shake displacement is input to the rocking vibration removal processing unit 18 described in "Means for Solving the Problem".

The rocking vibration removal processing section 18 removes a rocking vibration component, which is a high-frequency vibration, without giving a phase delay to the actual vibration. The new shake displacement thus obtained and the shake speed calculated by the differential calculation unit 19 are input to the control calculation processing unit 20.

The control calculation processing section 20 calculates a trolley speed command value by performing, for example, an optimum control calculation for multiplying the input data of the total of five points by multiplying the input data by a constant gain. The trolley speed command value is converted into an analog signal by the D / A converter 21 and is input to the trolley drive device 5 as the trolley speed command signal 16 to drive the trolley and perform steadying.

[0030]

According to the present invention, a target speed setting signal of a trolley for suspending a suspended load with a rope and traversing and transporting the trolley, a position and speed signal of the trolley, and a swing signal of the suspended load are input, respectively. High-frequency vibration noise is removed from the vibration signal, a signal from which the high-frequency vibration noise is removed, a target speed setting signal, a trolley speed command is calculated and output based on the position and speed signals, and the trolley speed command is used to output the trolley speed command. In a steady rest device for controlling the swing of a suspended load,
The high frequency vibration elimination is performed by a rocking vibration elimination processing means. Therefore, by replacing the conventionally performed low-pass filter processing for removing the high-frequency rocking vibration over the vibration displacement with the locking vibration elimination processing of the present invention, no phase delay is added to the vibration. As a result, the time required for the damping of the run-out is reduced, and the cargo handling time is reduced.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a suspension device for hanging loads according to an embodiment of the present invention.

FIG. 2 is an overall system configuration diagram of a suspension device for hanging loads according to an embodiment of the present invention.

FIG. 3 is a block diagram of a locking vibration elimination process used in the suspension device of the present invention;

FIG. 4 is a characteristic diagram of a bandpass filter used in the suspension device of the present invention;

FIG. 5 is a characteristic diagram of a notch filter used in the suspension device of the present invention;

FIG. 6 is a diagram showing an influence on a run-out detection by a notch filter used in the anti-sway device for a suspended load according to the present invention;
(A) is a gain characteristic, and (b) is a phase characteristic.

FIG. 7 is an overall configuration diagram of a conventional suspension device for hanging loads.

FIG. 8 is an overall system configuration diagram of a conventional suspended load steadying device.

FIGS. 9A and 9B are explanatory diagrams showing a state of swing and rocking of a suspended load, wherein FIG. 9A shows swing vibration and FIG. 9B shows rocking vibration, respectively.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Crane 2 Trolley 3 Suspended load 4 Hanging rope 5 Trolley drive device 6 Drive rope 7 Machine room 8 Camera 9 Mark 10 Operation panel 12 Notch command signal 13 Deflection displacement detection signal 14 Trolley position detection signal 15 Trolley speed detection signal 16 Trolley speed command Signal 17 A / D conversion unit 18 Locking vibration removal processing unit 19 Differential calculation unit 20 Control calculation unit 21 D / A conversion unit 110 Control device

Claims (1)

[Claims] 1. A target speed setting signal of a trolley for suspending a suspended load with a rope, and traversing and transporting the trolley, a position and speed signal of the trolley, and a swing signal of the suspended load. Removes the high-frequency vibration noise, calculates and outputs a trolley speed command based on the signal from which the high-frequency vibration noise is removed, the target speed setting signal, the position and the speed signal, and outputs the swing of the suspended load according to the trolley speed command. In the steadying device for a suspended load, the high frequency vibration elimination is performed by a rocking vibration elimination processing means.