EP4174013A1 - Method for moving a load with a crane - Google Patents

Abstract

The invention relates to a method for moving a load (16) using a crane (2). In order to achieve faster positioning of the load and thus higher turnover rates compared to the prior art, it is proposed that the load (16) be attached to a trolley (8) via cable-like attachment means (12, 14) which is used for moving the load (16) is moved horizontally, oscillation of the load (16) during movement being reduced by means of mechanical sway control, at least one controlled system parameter (28) of the mechanical sway control being taken into account in a controlled system (30) of an electronic sway control system (26). , wherein a position (X_L) and/or speed (V_L) of the load (16) by means of the electronic anti-sway system (26) via a movement parameter of the trolley (8) is controlled.

Description

The invention relates to a method for moving a load using a crane.

Furthermore, the invention relates to a control unit with means for carrying out such a method.

The invention also relates to a computer program for carrying out such a method when running in a control unit.

Furthermore, the invention relates to a system for sway control having at least one drive device for a trolley and a control unit.

In addition, the invention relates to a crane having at least one such system.

Cranes, in particular so-called gantry cranes, are used to transfer loads, for example from a ship to a truck or a flat wagon, in particular rail wagons, which have a substantially horizontally oriented boom and a trolley that can be moved along the boom. In such a transport process, there is the challenge that the load is stimulated to swing, in particular by the movement of the trolley and by external influences such as wind. In order to deposit the load accurately, it is necessary to minimize the pendulum movement of the load. When handling loads, a predetermined trajectory is usually driven with at least one lifting and lowering process, so that an oscillation, in particular mechanical, can be adequately damped by a short pendulum length. This results in a reduction in turnover numbers during a given time window.

From the disclosure document DE 30 05 461 A1 discloses a crane with an anti-sway system, in which setpoint curves for travel speed and sway angle are calculated and fed to a control device for the travel drive. The setpoint curves are calculated in a computing device from input variables such as rope length and weight of a load on the basis of equations that apply to a mechanical vibration system. During the acceleration and braking processes, the computing device includes a number of switchover points in the calculation of the setpoint curves and uses these as a measure for specifying a drive torque or drive current. The setpoint curves are determined in such a way that the drive torque initially assumes a maximum value when starting or braking, then drops to almost zero and then has the maximum value again by the end of the starting or braking process. This ensures that the oscillation angle is zero at the end of the acceleration or braking process.

The disclosure document EP 2 878 567 A1 describes a method for determining at least one pendulum angle of a load picked up by a load transport device, the load being attached to at least one suspension point on the load transport device via at least one rope-like fastening means and the at least one suspension point being movable by means of at least one drive device, in which the pendulum angle is in the direction of movement and/or one of the time derivatives of the swing angle in the direction of movement is calculated at least on the basis of at least one operating variable of the at least one drive device and a variable representing the actual speed of the suspension point using at least one computing device.

The disclosure document EP 2 902 356 A1 describes a crane for handling a load, which has a lower load suspension point and an upper load suspension point, which are connected to one another via a cable system. A focus a load connected to the lower load attachment point is below the lower load attachment point. A deflection angle of a pendulum movement and/or a time derivative of the deflection angle of the pendulum movement, which the load carries out around the upper load suspension point, based on a vertical plane containing the upper load suspension point, is detected by means of a detection device. A control variable acting on the load is determined by a control device using a control law. An actuating device of the crane is controlled by the control device according to the determined manipulated variable, so that a tilting moment about the lower load suspension point is introduced into the load by means of the actuating device within the vertical plane. The tilting moment introduced into the load counteracts the oscillating movement of the load around the upper load suspension point.

Against this background, the invention is based on the object of specifying a method for moving a load with a crane which, in comparison to the prior art, enables the load to be positioned more quickly and thus enables higher turnover rates.

The object is achieved according to the invention by a method for moving a load with a crane, the load being attached to a trolley via cable-like fastening means, which is moved horizontally to move the load, with oscillation of the load during movement being reduced by means of mechanical pendulum damping , wherein at least one controlled system parameter of the mechanical sway control is taken into account in a controlled system of an electronic sway control system, wherein a position and/or speed of the load is controlled by means of the electronic sway control system via a movement parameter of the trolley.

Furthermore, the object is achieved according to the invention by a control unit with means for carrying out such a method.

Furthermore, the object is achieved according to the invention by a computer program for carrying out such a method when running in a control unit.

Furthermore, the object is achieved according to the invention by a system for damping oscillations having at least one drive device for a trolley and a control unit.

In addition, the object is achieved according to the invention by a crane having at least one such system.

The advantages and preferred configurations listed below in relation to the method can be transferred analogously to the control unit, the computer program, the system and the crane.

The invention is based on the idea of achieving higher turnover rates by improving the pendulum damping when moving a load with a crane, since in this way, among other things, lifting and lowering processes can be avoided. The load is fastened to a horizontally movable trolley via rope-like fastening means, such as ropes and/or chains, oscillation of the load during movement being reduced by means of mechanical pendulum damping. In particular, the load is linearly moved along a cantilever in one direction of movement. Mechanical pendulum damping is achieved, for example, by obliquely guided damping cables. It is proposed to combine the mechanical sway control with an electronic sway control system, with a controlled system parameter of the mechanical sway control being included in a controlled system of the electronic sway control system. A position of the load is controlled by the electronic anti-sway system via a movement parameter of the trolley. Such movement parameters are, for example, a speed, an acceleration and/or a change in rotational speed of the trolley or a drive device assigned to the trolley.

In this way, overshooting is avoided, for example. This goes hand in hand with quick positioning of the load and thus higher turnover rates as well as fewer lifting processes and thus lower energy consumption. In addition, the safety is increased by lower vibration amplitudes.

A processor of the control unit can be designed, inter alia, as a microprocessor, microcontroller or as an ASIC (application-specific integrated circuit). The computer program can include a “digital twin”, also known as a “digital twin”, or be designed as such. Such a digital twin is, for example, in the disclosure US 2017/0286572 A1 shown. The disclosure of US 2017/0286572 A1 is incorporated by reference into the present application. In this context, the “digital twin” is, for example, a digital representation of the components and/or functions relevant to the industrial process. Such a "digital twin" can be stored in a decentralized IT infrastructure, in particular in a cloud, and made available via a communication interface.

A further embodiment provides that the at least one controlled system parameter contains at least one oscillation frequency and at least one damping. Overshooting is avoided by including at least one oscillation frequency and at least one damping.

A further embodiment provides that the vibration frequency and the damping of the mechanical pendulum damping are determined with the aid of at least one sensor. Such a sensor can be, among other things, a camera, an acceleration sensor, a laser, but also a stopwatch. A sensor-based determination is simple and reliable.

A further embodiment provides that the at least one controlled system parameter of the mechanical pendulum damping is determined by means of at least one reference run. The at least one controlled system parameter, such as damping, can be determined easily and reliably by means of a reference run.

A further embodiment provides that reference runs are carried out at different hoist positions. In the case of obliquely guided damping ropes in particular, the mechanical damping is strongly dependent on the rope length, so that the at least one controlled system parameter can be modeled particularly flexibly by reference runs at different hoist positions

A further embodiment provides that a neural network is trained by the at least one reference run, with the at least one controlled system parameter of the mechanical pendulum damping being determined by the neural network. The use of such artificial intelligence additionally increases the flexibility of the modeling of the mechanical damping.

A further embodiment provides that the load is fastened to the trolley via inner rope-like fastening means and outer rope-like fastening means, with the mechanical pendulum damping being carried out at least partially by means of at least one outer rope-like fastening means. Such mechanical anti-sway control is easy and reliable to implement.

A further embodiment provides that at least one outer cable-like fastening means is actively tightened. In this way, slack rope formation is effectively prevented.

A further embodiment provides that while the load is being moved, an additional disturbance variable, in particular based on sensors, is detected, which is included in the controlled system of the electronic anti-sway system. Such a one The sensor can be, among other things, a camera, an acceleration sensor or a laser, which is attached to the trolley, for example. In this way, a current vibration state can be detected, in particular in real time, in order to take additional deviations between the model and reality into account.

A further embodiment provides that the trolley is moved by means of a drive device, the movement parameter of the trolley being varied by controlling the drive device. The drive device includes a converter, for example. Furthermore, a motor and/or a transmission can be assigned to the drive device. For example, the movement parameter of the trolley is varied via a converter control, which can be implemented easily and reliably.

FIG 1

eine schematische Darstellung eines Krans mit einem System zur Pendeldämpfung,

FIG 2

eine schematische Darstellung einer ersten Ausführung eines elektronischen Pendeldämpfungssystems,

FIG 3

eine schematische Darstellung einer zweiten Ausführung eines elektronischen Pendeldämpfungssystems,

FIG 4

eine schematische Darstellung des Bewegens einer Last mittels eines Krans zu zwei unterschiedlichen Zeitpunkten und

FIG 5

eine graphische Darstellung einer Position, einer Geschwindigkeit und eines Pendelwinkels.

The invention is described and explained in more detail below with reference to the exemplary embodiments illustrated in the figures. Show it

FIG 1

a schematic representation of a crane with a system for anti-sway control,

FIG 2

a schematic representation of a first embodiment of an electronic anti-sway system,

3

a schematic representation of a second embodiment of an electronic anti-sway system,

FIG 4

a schematic representation of the movement of a load by means of a crane at two different points in time and

5

a graphical representation of position, velocity and sway angle.

The exemplary embodiments explained below are preferred embodiments of the invention. In the exemplary embodiments, the described components of the embodiments each represent individual features of the invention to be considered independently of one another, which also develop the invention independently of one another and are therefore also to be regarded as part of the invention individually or in a combination other than the one shown. Furthermore, the described embodiments can also be supplemented by further features of the invention that have already been described.

The same reference symbols have the same meaning in the different figures.

FIG 1 shows a schematic representation of a crane 2 with a system 4 for sway control. The crane 2, which is embodied as a gantry crane, includes a trolley 8 that can be moved horizontally along a boom 6. A drive device 10 is also assigned to the crane 2, via which the trolley 8 can be moved along the boom 6 in both directions. A load 16, which is a container in the exemplary embodiment shown, is fastened to the trolley 8 via rope-like fastening means 12, 14, for example ropes and/or chains. By way of example, inner rope-like fastening means 12, so-called hoist ropes, and outer rope-like fastening means 14, so-called damping ropes, which are guided obliquely, for example, are provided.

For example, the load 16 is to be transported from a ship, not shown in the figure, to a truck, also not shown. The cable-like fastening means 12, 14 are fastened to a load handling device 18, a spreader and/or head block, which is provided on top of the load 16. A length of the cable-like fastening means 12, 14 can be changed by means of a hoist 20, for example to lift the load 16 or set it down and/or to overcome obstacles along a transport route. The drive device 10 , which includes a converter, for example, is controlled by a control unit 22 .

During the movement, the load 16 attached to the trolley 8 via the cable-like attachment means 12, 14 is subject to pendulum movements. Oscillation of the load 16 during movement is reduced by mechanical pendulum damping. For example, mechanical pendulum damping is carried out by actively tightening the damping cables to prevent slack in the cable. In addition or as an alternative, a swinging of the load is achieved by passive mechanical pendulum damping, for example by damping cables that are guided at an angle.

In order to minimize the swinging during the movement of the load 16, an electronic sway control system 26 is used, in which an influence of the mechanical sway control is taken into account. In particular, at least one controlled system parameter of the mechanical sway control is included in a controlled system of the electronic sway control system 26 . Such controlled system parameters are, for example, an oscillation frequency and damping. The vibration frequency and the damping can be determined with the aid of at least one sensor 24, for example. Such a sensor 24 can be, among other things, a camera, an acceleration sensor, a laser, but also a stopwatch. Among other things, the sensor 24 can be arranged on the trolley 8 .

• ω = Streckenkreisfreqeunz
• D = Dämpfung
• y = Ausgangsgröße
• u = Eingangsgröße
• k = Verstärkung

$$\ddot{\mathrm{u}}=\frac{y_{\mathit{max}}-y\left(t\to \infty \right)}{y\left(t\to \infty \right)}$$

ü = relative Überschwingweite $$D=\frac{-\ln \left(\ddot{\mathrm{u}}\right)}{\sqrt{{\mathrm{<figure-callout\; id="2"\; label="\pi "\; filenames="imgf0001.png,imgf0003.png"\; state="\{\{state\}\}">\pi </figure-callout>}}^2+{\left(\ln \left(\ddot{\mathrm{u}}\right)\right)}^2}}$$

$$T_{\mathit{an}}=\mathit{Zeit}\mathit{vom}\mathit{Start}\mathit{bis}\mathit{erstmals}y\left(t\to \infty \right)\mathit{erreichtwird}$$

$$\omega =\frac{\arccos \left(-D\right)}{T_{\mathit{an}}\sqrt{1-{\mathrm{<figure-callout\; id="2"\; label="D"\; filenames="imgf0001.png,imgf0003.png"\; state="\{\{state\}\}">D</figure-callout>}}^2}}$$

The determination of system parameters, in particular damping D and system angular frequency ω, can be determined, for example, via a build-up time and a relative overshoot range for an oscillating system with two conjugate complex pole pairs: $$\frac{1}{\omega }\cdot \frac{{\mathrm{i.e}}^{2}y\left(t\right)}{{\mathit{German}}^2}+\frac{2D}{\omega }\cdot \frac{\mathit{dy}\left(t\right)}{\mathit{German}}+y\left(t\right)=k\cdot \mathrm{and}\left(t\right)$$

• ω = track circular frequency
• D = damping
• y = output size
• u = input quantity
• k = gain

$$\ddot{\mathrm{and}}=\frac{y_{\mathit{Max}}-y\left(t\to \infty \right)}{y\left(t\to \infty \right)}$$

ü = relative overshoot $$D=\frac{-\ln \left(\ddot{\mathrm{and}}\right)}{\sqrt{{\mathrm{<figure-callout\; id="2"\; label="\pi "\; filenames="imgf0001.png,imgf0003.png"\; state="\{\{state\}\}">\pi </figure-callout>}}^2+{\left(\ln \left(\ddot{\mathrm{and}}\right)\right)}^2}}$$

$$T_{\mathit{at}}=\mathit{Time}\mathit{from\; the}\mathit{begin}\mathit{until}\mathit{first\; time}y\left(t\to \infty \right)\mathit{is\; reached}$$

$$\omega =\frac{\arccos \left(-D\right)}{T_{\mathit{at}}\sqrt{1-{\mathrm{<figure-callout\; id="2"\; label="D"\; filenames="imgf0001.png,imgf0003.png"\; state="\{\{state\}\}">D</figure-callout>}}^2}}$$

For example, the mechanical pendulum damping is simulated using a model that depicts the kinematics of at least part of the crane 2 . In particular, the model can be designed as a “digital twin” or be part of a “digital twin”. In this context, a “digital twin” is, for example, a digital representation of the components and/or functions relevant to the industrial process. Such a "digital twin" can be stored in a decentralized IT infrastructure, in particular in a cloud, and made available via a communication interface.

For example, the at least one controlled system parameter is determined using at least one reference run. In particular, reference runs are carried out with different hoist positions. A neural network can be trained using recorded data, for example from at least one reference run be, wherein the at least one controlled system parameter of the mechanical pendulum damping is determined by the neural network. A position of the load 16 is controlled via a movement parameter of the trolley 8 by the electronic anti-sway system 26 . Such a movement parameter can be, among other things, a speed, an acceleration and/or a change in rotational speed. The movement parameter can be controlled, among other things, by a converter control, eg PLC.

FIG 2 shows a schematic representation of a first embodiment of an electronic sway control system 26 with a controlled system 30 expanded by at least one controlled system parameter 28 of mechanical sway control. The at least one controlled system parameter 28 can be taken into account in algorithms of a pilot control 31 as a function of drive and mechanical dynamics limitations and target variables X _Z . The pilot control 31 generates at least one setpoint variable X _S . Target variables X _s are, for example, a target position, a target speed, a target acceleration and/or a target torque. A state variable n _R , which contains a state of the controlled system 30 with the at least one controlled system parameter 28 , for example rotational speed of the trolley, oscillation angle, oscillation damping, is processed further by a controller 32 . Additionally or alternatively, the one state variable n _R can contain a pendulum angular velocity and/or a position of the trolley 8 . Depending on the drive and mechanical dynamics limitations, control 32 outputs a manipulated variable X _R . Control variables X _R are, for example, a control position, a control speed, a control acceleration and/or a control torque. In this way, a position X _L and/or speed V _L of the load 16 is controlled in such a way that an oscillating movement of the load 16 is minimized. The further version of the electronic anti-sway system 26 in FIG 2 corresponds to the in FIG 1 .

3 shows a schematic representation of a second embodiment of an electronic anti-sway system 26. While the load 16 is being moved, an additional disturbance variable z, in particular sensor-based, is detected in order to take further deviations between the model and reality into account. The additional disturbance variable z, which can be, among other things, a movement of the load caused by the weather, is also included, particularly in real time, in the controlled system 30 of the electronic sway control system 26 . The further version of the electronic anti-sway system 26 in 3 corresponds to the in FIG 2 .

FIG 4 shows a schematic representation of the movement of a load 16 by means of a crane 2 at two different points in time t1, t2. ,The system 4 is not shown for reasons of clarity. The load 16 is linearly moved in a direction of movement 34 along the x-axis x. By using an electronic sway damping system 26, which takes into account the mechanical sway damping, it is possible to move the load 16 without a particularly noticeable lifting and lowering process, for example in the Z direction.

5 shows a graphic representation of a position x, a speed v and a pendulum angle α of a trolley 8 as a function of a time t during a movement of the load 16 according to FIG FIG 4 . The time is shown in seconds as an example. An ideal target position X _T , a setpoint position X _S and a regulated setpoint position X _S,R are shown. From the representation of the corresponding regulated target speed v _S,R in comparison to the target speed v _S in combination with the regulated sway angle α, it becomes clear that the speed control leads to the swaying movement of the load 16 being minimized.

In summary, the invention relates to a method for moving a load 16 with a crane 2. In order to achieve faster positioning of the load and thus higher turnover rates compared to the prior art, it is proposed that the load 16 is fastened to a trolley 8 via cable-like fastening means 12, 14, which is moved horizontally to move the load 16, oscillation of the load 16 during movement being reduced by means of mechanical pendulum damping, with at least one controlled system parameter 28 of the mechanical pendulum damping is taken into account in a controlled system 30 of an electronic anti-sway system 26, with a position X _L and/or speed V _L of the load 16 being controlled by means of the electronic anti-sway system 26 via a movement parameter of the trolley 8.

Claims (14)

Method for moving a load (16) with a crane (2), the load (16) being attached to a trolley (8) via cable-like attachment means (12, 14), which trolley is moved horizontally to move the load (16), swinging of the load (16) during movement is reduced by means of mechanical pendulum damping, wherein at least one controlled system parameter (28) of the mechanical sway control is taken into account in a controlled system (30) of an electronic sway control system (26), wherein a position (X _L ) and/or speed (V _L ) of the load (16) is controlled by means of the electronic anti-sway system (26) via a movement parameter of the trolley (8). Method according to claim 1,
wherein the at least one controlled system parameter (28) contains at least one oscillation frequency (ω) and at least one damping (D). Method according to claim 2,
wherein the vibration frequency (ω) and the damping (D) of the mechanical pendulum damping are determined with the aid of at least one sensor (24). Method according to one of claims 1 to 3,
wherein the at least one controlled system parameter (28) of the mechanical pendulum damping is determined by means of at least one reference run. Method according to claim 4,
whereby reference runs are carried out at different hoist positions. Method according to one of claims 3 or 4, a neural network being trained by the at least one reference run, wherein the at least one controlled system parameter (28) of the mechanical pendulum damping is determined by the neural network. Method according to one of the preceding claims, the load (16) being attached to the trolley (8) via inner rope-like fastening means (12) and outer rope-like fastening means (14), wherein the mechanical pendulum damping is carried out at least partially by means of at least one outer cable-like fastening means (14). Method according to claim 7,
wherein the at least one outer cable-like attachment means (14) is actively tightened. Method according to one of the preceding claims,
wherein during the movement of the load (16) an additional disturbance variable (z), in particular sensor-based, is detected, which enters the controlled system (30) of the electronic anti-sway system (26). Method according to one of the preceding claims, the trolley (8) being moved by means of a drive device (10), wherein the movement parameter of the trolley (8) is varied by controlling the drive device (10). Control unit (22) with means for carrying out a method according to one of the preceding claims. Computer program for carrying out a method according to one of Claims 1 to 10 when running in a control unit (22) according to Claim 11. System (4) for damping oscillations having at least one drive device (10) for a trolley (8) and a control unit (22) according to Claim 11. Crane (2) having at least one system (4) according to Claim 13.

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