JPH10139369A - Bracing control device for hung load - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control to reduce oscillation of a hung load not only at a target position but when a trolley is traveling. SOLUTION: A trolley 12 is hanging a hung load 14 by a rope 13 and traveling along a rail 11. This trolley 12 has a trolley displacement detector 22 for detecting a trolley position x1 and a trolley speed detector 22 for detecting trolley speed x2 and an oscillation motion detector 23 for detecting oscillation displacement x3 of the hanging load 14 and oscillation speed x4. A control device 26 provides a speed instruction u based on the detected values x1, x2, x3 and x4 and a trolley driving device 15 drives according to this speed instruction u and the trolley 12 travels. And also when the trolley is moved to a target position by control of the control device 26, the device controls such that controls to brace as the trolley 12 follows predetermined speed in the first half of the control and positions of the trolley and bracing controls when the trolley 12 approaches the target position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for controlling the steadying of a suspended load in a crane.

[0002]

2. Description of the Related Art FIG. 5 is a block diagram of a conventional apparatus for preventing steadying of a suspended load.
This will be described with reference to FIG. 7 showing the control characteristics.

[0003] As shown in FIG. 5, a trolley 012 is driven by a trolley driving device 015 to drive a rail 0.
11 can be run. A rope 013 hangs from the trolley 011.
By attaching 14, the suspended load 014 is carried.

The trolley 012 further includes a trolley displacement detector 021 for detecting a trolley position x1, a trolley speed detector 022 for detecting a trolley speed x2, and a shake motion detector for detecting a shake displacement x3 and a shake speed x4. 0
23 are provided.

[0005] The swing motion detector 023 includes a trolley 0
A camera attached vertically downward to the camera 12 detects a marker attached to the suspended load 014, and performs image processing on the captured image to detect a shake displacement x3 and a shake speed x4.

The detected trolley position x1, trolley speed x2, runout displacement x3, and runout speed x4 are stored in the control unit 02.
Sent to 6. The control device 026 performs a positioning optimum control operation described later by the built-in optimum control unit 032 (see FIG. 6), and outputs a speed command u. The trolley driving device 015 is driven according to the speed command u, and the trolley 0
12 runs.

In such a crane, when automatic operation is performed, it is necessary to incorporate a control for accurately positioning the suspended load 014 with respect to a designated target position.

[0008] It is known that a crane can be modeled as a bogie / pendulum system, and for such a model, the positioning of a suspended load can be realized by driving a trolley by feedback control by an optimal regulator. (Reference "Mechanical system control",
Katsuhisa Furuta et al., Ohmsha)

Here, an optimal control method of the crane will be described with reference to FIGS. 6 and 7. FIG. This control is performed by the control device 02
The control amount (here, the speed command u of the trolley) is calculated by the optimum control unit (optimum regulator) 032 according to the following control law (formula (1)).

[0010]

(Equation 1)

Here, x is a state quantity vector shown below, and each element is, in order from the left, a trolley position x1, a trolley speed x2, a swing displacement x3 of the suspended load, and a swing speed x4.
It is. That is, the following equation (2) is obtained.

[0012]

(Equation 2)

Further, K is a four-row gain vector shown in equation (3).

[0014]

(Equation 3)

Here, the above-mentioned gain vector K is an optimum gain determined by the following procedure.

(A) The equation of state of the following equation (4) is derived from the equation of motion derived from the trolley and pendulum motion model of FIG. This state equation expresses the vibration of the suspended load 014 as a linear differential equation as a spring-mass system, and a description thereof is omitted here, including a method of deriving the state equation. u and x are the above-mentioned manipulated variable and state variable vector, respectively, A is a transition matrix of 4 rows and 4 columns, and B is a drive matrix of 4 rows and 1 column.

[0017]

(Equation 4)

(B) With respect to the state equation of the above equation (4), the optimum gain K of the equation (6) for minimizing the evaluation function J of the following equation (5) is obtained. Note that Q is a 4-by-4 weight matrix. r is a weight coefficient.

[0019]

(Equation 5)

[0020]

(Equation 6)

By minimizing the evaluation function J in this manner, the optimum gain K for quickly setting all the elements of the state quantity to zero with the smallest possible operation amount (speed command) u is obtained.

In the control arithmetic unit 026,
Based on the optimum gain K obtained by the above-described calculation, the optimum operation amount is obtained by the product sum of the motion state amount by each of the detectors 021, 022, and 023 and the optimum gain K. This optimum operation amount is output as a control command signal (speed command u) of the trolley driving device 015, and the optimal control is executed by driving these.

At this time, the trolley 012 can be positioned at the target position by feeding back the position signal input of the trolley 012 (trolley position x1) as a relative position with respect to the trolley target position pset. 014 is also executed.
4 can be positioned at a given target position.

[0024]

When the control by such an optimum regulator is performed, the trolley is moved by changing the target position from the stopped state. At this time, since the trolley position is far away from the target position in the initial stage of the control, the trolley relative position x1 as the state amount becomes larger than the other state amounts, and the speed command u as the operation amount is also controlled. Immediately after, it takes a large value. The speed command u immediately after the start of the control is indicated by a dotted line in FIG.
2).

On the other hand, the initial state of the trolley is zero speed, and the acceleration and speed of the trolley are limited in a real crane. Therefore, in the initial stage of the control, acceleration at the maximum acceleration (time 0 to T1) and movement at the maximum speed (time T1 to T2) are performed. The trolley speed x2 is shown by a solid line in FIG.

Such a state of the trolley speed is effective for causing the trolley to reach the target position quickly.
This is a state in which feedback of the swing state of the suspended load is not working, and the approach to the target position is made with the swing generated due to the acceleration of the trolley remaining.

This not only reduces the safety of the trolley when moving, but also has a serious problem that the convergence time at the time of positioning is lengthened and the cargo handling efficiency is reduced.

In view of such a situation, in the present invention, in addition to the conventional optimal control, the optimal control for performing the anti-sway control while causing the trolley to follow a given speed command, We propose a steadying control device for a suspended load that has a switching device that switches according to.

[0029]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is directed to a crane for hanging a load by a rope member, a trolley motion state quantity detector for detecting a trolley motion state quantity, and a trolley hanging on the trolley. A load motion state quantity detector for detecting a motion state quantity of the suspended load, and a control device for performing a steadying control of the load based on a detection signal taken from each of the detectors. The apparatus is configured to drive the trolley with an optimal operation amount based on an optimal gain adjusted to follow a certain set speed and perform a steady rest control, and a speed follow-up optimal control unit, and to position the trolley at a certain target position. An optimal control unit for positioning which drives the trolley with an optimal operation amount based on the adjusted optimal gain and executes a steady rest control; and Operating condition-specific control selection unit for driving the trolley to select the positioning optimum control portion and suitable control unit, and having a.

In the present invention, the trolley motion state quantity detector includes a trolley displacement detector for detecting a trolley position and a trolley speed detector for detecting a trolley speed. A swing motion detector that detects a swing displacement and a swing speed of a suspended load, wherein the operating state-based control selection unit includes a speed following optimal control unit when the relative position between the trolley and the target position is larger than a set value. The trolley is selectively driven and, when the relative position between the trolley and the target position is smaller than a set value, the trolley is driven by selecting the optimal positioning control unit.

[Operation] In the present invention, when the trolley is moved to the target position, in the first half of the control, the trolley is controlled to follow the set speed and the steady rest is performed. Can be kept small. When the trolley approaches the target position, the control is switched to the conventional control of positioning and swaying the trolley, so that the swing of the suspended load at the time of control switching is small, and the convergence time of the swing by the conventional control is kept short. Can be.

[0032]

Embodiments of the present invention will be described below with reference to the drawings. 1 is an overall configuration diagram, FIG. 2 is a block diagram of a control device, FIG. 3 is a flowchart showing a control operation, FIG.
Is a control characteristic diagram.

As shown in FIG. 1, the trolley 12 can run on the rails 11 when driven by the trolley drive device 15. Rope 1 from trolley 11
3 hangs, and the hanging load 14 is carried by attaching the hanging load 14 to the tip of the rope 13.

The trolley 12 has a trolley position x
1, a trolley speed detector 22 for detecting a trolley speed x2, and a deflection displacement x
3 and a shake motion detector 23 for detecting a shake speed x4.

The swaying motion detector 23 includes the trolley 12
With the camera mounted vertically downward on the
Is a type of detector that captures a marker attached to the camera and processes the captured image to detect a shake displacement x3 and a shake speed x4.

The detected trolley position x1, trolley speed x2, deflection displacement x3, deflection speed x4 are determined by the control unit 26.
Sent to The control device 26 has a built-in optimal control unit 3
1, 32 (see FIG. 2), as described later, in the first half of the control, the trolley 12 controls the steady rest while following the set speed to keep the swing of the suspended load 14 small (added by the present invention). When the trolley 12 approaches the target position, the control is switched to the control for performing the positioning of the trolley 12 and the anti-sway control (control conventionally performed). The trolley drive device 15 is driven according to the speed command u, and the trolley 012 travels.

As shown in FIG. 2, the control device 26 controls the trolley 12 to follow the set speed vset so as to make the trolley 12 follow the set speed vset, and controls the trolley for positioning and steadying. Positioning optimal control unit 3
2 is arranged.

The measured values detected by the detectors 21, 22, and 23 are input to these optimal control units 31 and 32. Regarding the trolley position, the relative position with respect to the target position pset is used as a control input. = X1-pset, and the relative position x1 'is used as a control input.

As for the input to the acceleration constant speed optimum control unit 31, in order to make the trolley speed a relative speed from the set speed vset, x2 '= x2-vset, and the relative speed x2' to the optimum control unit 31. Input signal.

Since the speed command u1 output from the acceleration constant speed optimum control unit 31 is also a relative speed from the set speed, u1 '= u1 + vset is set, and this is calculated by the optimum control unit 31 (trolley speed command). And

The processing performed by the acceleration / constant speed optimum control unit 31 is as follows. That is, the optimal control gain is obtained in the same manner as the conventional control gain. However, in the control for following the set speed, the gain for multiplying the trolley position is unnecessary, so the weight matrix Q ′ set so that the gain for multiplying the trolley position becomes zero. Is used to find an optimal gain K ′ that minimizes the next evaluation function J ′.

[0042]

(Equation 7)

[0043]

(Equation 8)

The output signal trolley speed command u
1 'is a value obtained by adding the set speed vset as described above.

The positioning optimum control unit 32 performs the same calculation as the conventional optimum control unit 032 shown in FIG. 6 to provide a trolley speed command u2 for positioning the trolley and preventing the trolley from oscillating.
Is output.

The operation-state-specific control selection unit 33 includes a trolley speed command u1 'of the acceleration constant speed optimum control unit 31, a trolley speed command u2 calculated by the positioning optimum control unit 32, and a relative position of the trolley 12 from the target position pset. x
Input 1 '. In the operation state-based control selection unit 33, the relative position x1 ′ of the trolley 12 from the target position pset.
Is larger than a certain set value, the result (trolley speed command) u1 ′ of the acceleration constant speed optimum control unit 31 is changed to the speed command u
When the relative position x1 ′ is smaller than a certain set value, a process of switching the trolley speed command u2, which is the result of the positioning optimum control unit 32, to be output as the speed command u is performed.

The speed command u1 'or speed command u2 selected by the operation state-based control selection section 33 is applied to the trolley driving device 1.
5 to drive the trolley 12.

The processing in the control device 26 is summarized as follows. That is, the following will be described with reference to the flowchart shown in FIG.

[Step 1] Each detector 21, 22, 23
Signals x1, x2, x3, and x4.

[Step 2] The relative position x1 'of the trolley from the target position is calculated as follows. x1 '= x1-pset The relative speed x2' from the set speed of the trolley is calculated as follows. x2 '= x2-vset

[Step 3] Based on equation (9), an acceleration constant speed optimal control calculation is performed. Further, as shown in Expression (10), the set speed is added to the calculation result.

[0052]

(Equation 9)

[0053]

(Equation 10)

[Step 4] A positioning optimum control calculation is performed based on the equation (11).

[0055]

[Equation 11]

[Step 5] It is determined whether the relative position of the trolley from the target position is larger than a certain set value.

[Step 6] If the relative position of the trolley from the target position is larger than a certain set value, the result of the acceleration constant speed optimal control is set as a trolley speed command. That is, u = u1 ′.

[Step 7] On the other hand, if the relative position of the trolley from the target position is smaller than a certain set value, the result of the positioning optimal control is used as a trolley speed command. That is, u = u2.

[0059]

As described above, according to the present invention, there are provided two control gains, namely, a control for obtaining the trolley speed and the shake and a control for obtaining the trolley position and the shake, as the control amounts. Therefore, it is possible to configure a suspension control device for the suspension of the suspended load which can keep the vibration of the suspended load small even during the traveling of the trolley.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing a suspension control device for a suspended load according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a swing load steadying control device according to an embodiment of the present invention.

FIG. 3 is a flowchart illustrating a process performed by the control device.

FIG. 4 is a characteristic diagram showing a control characteristic of the steady rest control device for a suspended load according to the present invention.

FIG. 5 is an overall configuration diagram showing a conventional suspended load control device.

FIG. 6 is a block diagram showing a conventional suspended load steadying control device.

FIG. 7 is a characteristic diagram showing control characteristics of a conventional suspension control device for a suspended load.

[Explanation of symbols]

 Reference Signs List 11 rail 12 trolley 13 rope 14 suspended load 15 trolley drive device 21 trolley displacement detector 22 trolley speed detector 23 swing motion detector 26 control device 31 acceleration constant speed optimal control unit 32 positioning optimal control unit 33 control selection unit for each operation state x1 Trolley position x2 Trolley speed x3 Shake displacement x4 Shake speed x1 'Relative position x2' Relative speed u Speed command u1 'Trolley speed command u2 Trolley speed command

Claims (2)

[Claims] 1. A crane in which a load is hung by a rope member, a trolley motion state detector for detecting a motion state of the trolley, and a load motion state for detecting a motion state of a load suspended on the trolley. An amount detector, and a control device for performing a steadying control of the suspended load based on a detection signal taken from each of the detectors, wherein the control device is an optimal device adjusted to follow a certain set speed. An optimal control unit for speed following that drives the trolley with the optimal operation amount based on the gain and executes the steadying control; and drives the trolley with the optimal operation amount based on the optimal gain adjusted to be positioned at a certain target position. And selecting the optimal control unit for speed following and the optimal control unit for positioning based on the operation state amount of the trolley. Steadying control apparatus of the suspended load, characterized in that it has a, operating condition-specific control selection unit for driving the trolley. 2. The trolley motion state quantity detector is a trolley displacement detector for detecting a trolley position, and a trolley speed detector for detecting a trolley speed. A deflection motion detector that detects a deflection displacement and a deflection speed, wherein the operation-state-specific control selection unit selects the speed following optimal control unit when the relative position between the trolley and the target position is larger than a set value. When the trolley is driven and the relative position between the trolley and the target position is smaller than the set value,
A steady rest control device for a suspended load, wherein a trolley is driven by selecting an optimal control unit for positioning.