DE202023002939U1 - Device for operating a jib crane and jib crane - Google Patents

Abstract

Device, in particular control device (100), for operating a jib crane (2) with the aid of a state control, wherein the state control effects a control of a movement of a suspended load (L) at least in one direction of movement and is based on a state vector, wherein the device is designed to:
- Recording state variables of the state vector, which includes information on a position and a speed (x', θ') of a movable suspension point (AUP) to which a load system comprising a hoisting rope (HSL), a load suspension device (UF) arranged at a lower end of the hoisting rope (HSL) and a load (L) suspended below the load suspension device (UF) and information on a load position (φ _x , φ _y ) and a load speed (φ' _x , φ' _y ) of a center of mass of the load system with respect to the suspension point (AUP),
- Determining at least one manipulated variable (u* _LK , u* _DW , u* _HW ) for moving the suspension point (AUP) in the at least one direction of movement based on the state control;
- Control of the jib crane (2) depending on at least one control variable (u* _LK , u* _DW . u* _HW ).

Description

Technical area

The invention relates to jib cranes for controlling a movement of a suspended load and in particular to measures for preventing pendulum swing.

Technical background

Cranes, and in particular jib cranes or handling cranes, such as tower cranes, mobile cranes, and the like, enable the movement of a load by suspending the load from a hoist rope on a boom, lifting the load, moving the load in a substantially horizontal plane, and setting it down. The movement of the boom is effected by suitable drive devices, and the lifting and setting down of the load is carried out using a hoist connected to a hoist rope.

For handling cranes, the time required for a transport cycle can be crucial for trouble-free operation. During a transport cycle, the goal is to minimize unproductive downtime and optimize the crane's productive operating time.

For example, in a tower crane, the load is moved by rotating the boom and by moving a trolley along the boom. In mobile slewing cranes, the load is moved by rotating the boom and, if necessary, by luffing the boom up and down about a horizontal luffing axis. The drive devices and the hoist are usually controlled manually by a crane operator using suitable controls on a crane control unit. During acceleration and braking, the suspended load is deflected relative to the suspension point on the boom, thus triggering a pendulum movement. A pendulum load can pose a potential hazard to both construction workers and construction equipment. To prevent such undesirable pendulum movement of the suspended load, state-of-the-art measures for dampening the pendulum movement during crane operation are known.

For example, the printed publication DE 10 2009 032 270 A1 A method for controlling a drive of a mobile crane, using a target movement of the boom tip as the input variable, based on which a control variable is calculated to control the drive. When calculating the control variable, the vibration dynamics of the system consisting of the drive and the crane structure are taken into account in order to reduce natural vibrations.

From the printed publication EP 1 628 902 B1 A crane is designed for handling loads suspended from a load rope, with a slewing gear for rotating the crane, a luffing gear for tilting a boom, and a hoist for lifting the load suspended from the rope. A path control system is used to calculate an optimal control trajectory based on a nonlinear model approach and to update it through feedback of state variables. The output variables of the path control system are used directly or indirectly as input variables in a closed-loop control system for the position or speed of the crane. The reference variables for the path control system are generated in such a way that a load movement with minimized pendulum deflections is achieved.

From the EP 1 652 810 B1 A method for controlling a crane operating unit for suppressing vibrations of a load suspended from a rope of a crane is known in which control is carried out by actuating a control device having a filter unit.

To prevent pendulum oscillations, it is known to use predictive control of the crane movement in a crane to suppress pendulum oscillations. See, for example, J. Smoczek et al., “Robust Predictive Control of an Overhead Crane,” https://doi.org/10.5604/01.3001.0010.2940 .

From the brochure “ Liebherr Electronics” of Liebherr Werk Nenzing GmbH from 09/2012 The “Cycoptronic” function is known, which is used to demonstrate the pendulum-free operation of a mobile harbor crane when handling ISO containers between freighters and a harbor edge area.

Especially in complex crane structures, conventional sway damping devices are insufficient to adequately dampen or suppress sway. In particular, the diverse dynamic effects during lifting, lowering, and moving of the load due to the diverse deformations of the crane structure cannot be adequately modeled using a physical model, so the sway cannot be adequately damped.

Conventional methods are generally based on an assumed load position, which is determined approximately, for example, using a hoist rope angle relative to the vertical, usually at the hoist rope suspension point on the boom. However, wind pressure and other dynamic influences can lead to transverse oscillations of the hoist rope, so that the measured hoist rope angle does not correspond to the angle of the distance between the suspension point on the boom and the load center of gravity. Furthermore, in crane operation, the load to be suspended is attached to a load-handling device, such as a bottom block, so that the non-negligible weight of the load-handling device creates a double pendulum system that often executes a chaotic oscillating motion when excited. This is difficult to predict using conventional physical models, significantly impairing the quality of sway damping based solely on the hoist rope angle. In addition, the insufficient predictability of the pendulum oscillation of the load can also lead to an intervention of the pendulum damping algorithm, which in the worst case scenario can lead to an increase in the pendulum oscillation.

It is an object of the present invention to provide a method and a device for operating a jib crane as well as a jib crane and a computer program product for carrying out the method, which dampens or suppresses a pendulum oscillation in an improved manner and further enables additional operating modes in order to make the transport process of the load safer, faster and easier to carry out.

Disclosure of the invention

This object is achieved by the method for operating a jib crane using a state control according to claim 1 as well as a corresponding device and a jib crane according to the independent claims.

Further embodiments are specified in the dependent claims.

• - Erfassen von Zustandsgrößen des Zustandsvektors, der Angaben zu einer Position und einer Geschwindigkeit eines bewegbaren Aufhängungspunkt, an den ein Lastsystem, das ein Hubseil, eine an einem unteren Ende des Hubseils angeordnete Lastaufnahmeeinrichtung und eine unterhalb der Lastaufnahmeeinrichtung angehängte Last umfasst, angehängt ist, und Angaben zu einer Lastposition und einer Lastgeschwindigkeit eines Masseschwerpunkts des Lastsystems relativ zu dem Aufhängungspunkt umfassen,
• - Ermitteln mindestens einer Stellgröße zur Bewegung des Aufhängungspunktes in der zumindest einen Bewegungsrichtung basierend auf der Zustandsregelung;
• - Betreiben des Auslegerdrehkrans abhängig von der mindestens einen Stellgröße.

According to a first aspect, a method for operating a jib crane using a state control is provided, wherein the state control effects a control of a movement of a suspended load at least in one direction of movement and is based on a state vector, comprising the following steps:

• - Recording state variables of the state vector, which includes information on a position and a speed of a movable suspension point to which a load system comprising a hoisting rope, a load-handling device arranged at a lower end of the hoisting rope and a load suspended below the load-handling device is attached, and information on a load position and a load speed of a center of mass of the load system relative to the suspension point,
• - Determining at least one manipulated variable for moving the suspension point in the at least one direction of movement based on the state control;
• - Operation of the jib crane depending on at least one control variable.

As mentioned at the beginning, a fundamental problem when transporting a load using a jib crane is dampening or suppressing the pendulum oscillation of the suspended load to such an extent that construction workers can lift and lower the load, as well as suspend and unsuspend the load, quickly and safely. The goal is to dampen the pendulum oscillation during every phase of load transport, preventing any pendulum oscillation from occurring, thus allowing the load to be lifted and lowered in a shorter time.

The load system comprises the suspended load, a load suspension device, a hoisting rope of adjustable length that connects the load suspension device to the suspension point, and a sling with which the suspended load is suspended from the load suspension device. Due to the massed hoisting rope and the massed load suspension device at the lower end of the hoisting rope, the The oscillating load system with the suspended load is a multiple pendulum system that is not trivial to model and typically leads to erratic pendulum oscillations when subjected to lateral force excitations. Therefore, an accurate determination of the actual load position is not easily possible.

The actual load position may indicate a relative position of a center of mass of the entire load system with respect to the suspension point on the boom and may be provided, for example, as an indication of a lateral load deflection relative to a perpendicular through the suspension point and/or as an indication of a sway angle relative to a suspension point of the load system with respect to a perpendicular through the suspension point in one or more lateral directions of movement. The load velocity may correspond to the relative velocity of the center of mass of the entire load system with respect to the suspension point.

Common pendulum oscillation damping methods for suppressing pendulum oscillation estimate the load position, i.e., the load deflection or oscillation angle, based exclusively on the hoist rope angle of the hoist rope at the boom suspension point and the hoist rope length, and the load speed by determining a derivative of the hoist rope angle. However, in reality, this does not allow for a useful determination of the load position and load speed for state control. Using such a simplified determination of the load position leads, especially when using a state controller, to inaccurate control behavior and consequently to inadequate suppression of pendulum oscillation during crane operation.

In this regard, it is advantageous to design a control system for moving the load to an actual or an improved determined load position and thus to eliminate the disturbing effect of the estimation error for the load position.

For this purpose, the load position of the center of gravity can be determined depending on a hoist rope angle, which indicates an angular deviation of the hoist rope attached to the suspension point from the vertical through the suspension point, on a load rope angle, which indicates an angular deviation of a center of gravity with respect to a suspension point on the load suspension device from the vertical, on a hoist rope length between the suspension point and a center of gravity of the load suspension device, and on a load rope length, i.e. a length of the lifting device, between the suspension point and the center of gravity of the load.

A more precise determination of the load position is made possible by using state control for the operation of the jib crane. State control is suitable for implementing various operating modes of the jib crane. State control is based on a state vector and, given the provided target specifications, delivers a manipulated variable for at least one direction of movement, in particular an adjustment speed of a drive device, such as an adjustment speed of a trolley of a tower crane or an adjustment speed of a luffing angle of a boom of a mobile slewing crane and/or an adjustment speed of a slewing gear. State control is executed cyclically according to time-defined control cycles, in particular with control cycle durations of between 10 ms and 500 ms, preferably between 50 ms and 150 ms.

It has been shown that a state control system operated on a control unit of the jib crane is advantageous with a state vector that specifies, for a direction of movement, on the one hand, the position and speed of the suspension point of the load system and, on the other hand, the load position, i.e. the position of the center of mass of the load system relative to the suspension point (e.g. load deflection, oscillation angle).

The load velocity, i.e., the oscillation angle velocity, is determined by temporally differentiating the change in load position (load deflection/oscillation angle). The oscillation angle indicates the angle of the actual load deflection, i.e., the deflection of the center of mass, relative to the suspension point on the boom to the perpendicular through the suspension point in at least one direction of movement, i.e., in a radial x-direction and/or a tangential y-direction.

The direct application of a state control to such a state vector makes it possible to avoid any inaccuracies resulting from elastic deformations and/or caused by transverse influences on the load and the load attachment. The state control can be designed, for example, to control the slewing gear for the boom rotation and the drive device for a boom luffing in a mobile crane or, for example, to control the slewing gear for the boom rotation and a The trolley for moving a trolley and the hoist must act separately, as the dynamics of the individual motion systems are very different. Thus, a radial movement of the load can be controlled by controlling the corresponding drive device for luffing or by controlling the trolley to move the trolley according to a control variable, while a tangential movement, i.e., around the axis of rotation of the boom, can be achieved by controlling the slewing gear for boom rotation.

The controls can be designed and implemented separately from one another. This allows various functions, including a sway damping function, to be implemented in different directions of motion, and the corresponding state controllers can be adapted appropriately to the different control dynamics of the drive devices (slewing gear, trolley, etc.).

By using a state controller, it is possible to precisely specify the trajectories of the manipulated variables for controlling the drive devices for moving the suspended load, so that, for example, pendulum swinging of the moving load is avoided during load movement.

Suppressing the swinging of the load in all phases during crane operation makes it possible to suppress swaying at any time during the load transport process, i.e. a process of suspending the load, lifting the load, moving the load, lowering the load and unsuspending the load, and thus ensure a faster transport process, as waiting times due to swinging processes can be avoided.

The load system forms a multiple pendulum system between the suspension point on the trolley LK and the center of mass of the suspended load. This system includes other non-negligible masses along the load suspension, such as the load suspension device, which forms another vertex of a pendulum motion. It was determined that the double or multiple pendulum system of the load system, consisting of hoist rope, load suspension device, load rope, and suspended load, can be considered a single pendulum for the implementation of state control if the load position relative to the suspension point on the boom is determined more accurately using sensor fusion or alternative methods.

In principle, the actual load position can be determined in a variety of ways. For example, a localization system that determines a position vector from a fixed point and a point on the suspended load can be used to determine the load position. For this purpose, camera- or transponder-based localization systems can be used, for example, as described in DE 10 2020 120 699 A1 known.

Furthermore, determining the relative load position by merging sensor data from a first angle sensor device and a second angle sensor device has proven effective. These two devices capture angle information and transmit it to a control unit. The first angle sensor device is arranged at the suspension point of the hoist rope on the boom to determine a hoist rope angle in the x- and/or y-direction, i.e., in the radial and/or tangential direction relative to the boom rotation axis. The hoist rope angle is determined relative to the perpendicular through the suspension point.

Since the hoist rope angle of the hoist rope must be determined relative to the vertical, compensation of the measured boom angle at the hoist rope suspension point can preferably be provided. This can take into account a rotation angle difference from the rotation angle around the boom pivot point due to elastic bending of the boom, e.g., using a known physical model or through a measurement. The luffing angle (in the vertical direction) and a luffing angle difference (tilt angle) of the boom in the vertical direction due to elastic bending of the boom can also be taken into account, e.g., using a known physical model or through a measurement.

Using the second angle sensor device, e.g. on the load suspension device attached to the hoist rope, a load rope angle of the suspended load with respect to the vertical through a suspension point of the load on the load suspension device can be determined in the x- and/or y-direction. By fusing the hoist rope angle and the load rope angle (each in the same direction), with knowledge of the hoist rope length, ie the distance between the suspension point on the boom and the center of mass of the load suspension device, and with knowledge or specification of the length of the sling or the load rope with which the load is suspended from the load-handling device, the relative load position, i.e. the lateral load deflection of the load system's center of mass relative to the vertical through the suspension point or the pendulum angle of the load system's center of mass relative to the vertical through the suspension point on the boom, can be determined. The load position can be determined by applying trigonometric functions known per se or by an approximation based on a linear function due to the relatively small hoist rope angles and load rope angles of < 5° each.

The jib crane can then be operated based on the assumed virtual single pendulum system using the state controller without considering the elastic deformation of crane structures due to torsional and bending moments, so that the implementation of the corresponding state control is possible in a simpler way.

It can be provided that the state control is implemented in that, when a crane state changes, in particular when a hoist rope length changes, and in particular depending on a mass of the suspended load and/or a radial position of the suspension point, a parameterization of a state space description is updated in the state space and a linear combination of the control deviations of the state variables is determined by a pole specification method or a method based on the LQ method, which is used to calculate the at least one manipulated variable for moving the suspension point.

Thus, a state space representation for a direction of movement in the radial direction (x-direction) corresponds to $$\left[\begin{array}{c}{x}^{\prime }\\ x^{″}\\ {{\phi }^{\prime }}_x\\ {{\phi }^{″}}_x\end{array}\right]=A_{LK}\left[\begin{array}{c}x\\ x^{\prime }\\ {\phi }_x\\ {{\phi }^{\prime }}_x\end{array}\right]+b_{LK}{u}_{LK}$$

$$B_{LK}=\left[\begin{array}{c}0\\ b1\\ 0\\ b2\end{array}\right]$$

An example parameterization of the system matrix A _LK and the input vector b _LK is as follows: $$A_{LK}=\left[\begin{array}{cccc}0& 1& 0& 0\\ 0& a1& 0& 0\\ 0& 0& 0& 1\\ 0& a2& a3& 0\end{array}\right]$$

$$B_{LK}=\left[\begin{array}{c}0\\ \mathrm{<figure-callout\; id="1"\; label="b"\; filenames="DE202023002939U1\_0085.png"\; state="\{\{state\}\}">b</figure-callout>}1\\ 0\\ b2\end{array}\right]$$

wobei x der radialen x-Position des Aufhängungspunkts, φ_x dem Pendelwinkel (als Lastposition) in radialer Richtung, c einer vorgegeben Konstanten, T einer Zeitkonstanten einer Übergangsfunktion des Folgens des Aufhängungspunkts bei Ansteuerung mit der Stellgröße u_LK (vorzugsweise einer Geschwindigkeit), g der Gravitationskonstanten und I einer Pendellänge I des Lastsystems entsprechen. „' “bedeutet die erste zeitliche Ableitung und„ “ " die zweite zeitliche Ableitung. Z entspricht dem Zustandsvektor, A_LK einer System-Matrix und b_LK einem Eingangsvektor. Auch andere Parametrisierungen der System-Matrix A_LK und des Eingangsvektors b_LK sind möglich. Die System-Matrix A_LK entspricht einer 4x4 System-Matrix und b_LK einem 4-dimensionalen Eingangsvektor mit Zustandsraumparametern der Zustandsraumdarstellung für die radiale Bewegung des Aufhängungspunkts.And for example: $$\left[\begin{array}{c}{x}^{\prime }\\ x^{″}\\ {\phi }^{\prime }\\ {{\phi }^{″}}_x\end{array}\right]=\left[\begin{array}{cccc}0& 1& 0& 0\\ 0& -\frac{1}{\mathrm{<figure-callout\; id="0"\; label="T"\; filenames="DE202023002939U1\_0087.png"\; state="\{\{state\}\}">T</figure-callout>}}& 0& 0\\ 0& 0& 0& 1\\ 0& \frac{1}{lT}& -\frac{g}{l}& 0\end{array}\right]\left[\begin{array}{c}x\\ x^{\prime }\\ {\phi }_x\\ {{\phi }^{\prime }}_x\end{array}\right]+\left[\begin{array}{c}0\\ \frac{C}{T}\\ 0\\ \frac{C}{lT}\end{array}\right]u_{LK}$$

where x is the radial x-position of the suspension point, φ _x is the pendulum angle (as load position) in the radial direction, c is a given constant, T is a time constant of a transition function of following the suspension point when controlled with the manipulated variable u _LK (preferably a speed), g is the gravitational constant and I is a pendulum length I of the load system. "'" means the first time derivative and """ the second time derivative. Z corresponds to the state vector, A _LK to a system matrix and b _LK to an input vector. Other parameterizations of the system matrix A _LK and the input vector b _LK are also possible. The system matrix A _LK corresponds to a 4x4 system matrix and b _{LK to} a 4- dimensional input vector with state space parameters of the state space representation for the radial motion of the suspension point.

Here, the parameterization of the system matrix A _LK and the input vector b _LK changes with each change of the pendulum length I.

mit t dem aktuellen Zeitschritt der Regelung, u*_LK der Stellgröße der Regelung und x(t), x'(t), φ_x(t), φ'_x(t) den aktuellen gemessenen und ermittelten Zustandsgrößen.By applying a pole specification method or an LQ method, an x-direction related control vector Kx= [K1, K2, K3, K4] ^T can be obtained for an updated system matrix A _LK for a control equation that is applied to the movement of the suspension point: $$\begin{array}{l}{u}^{\ast }{}_{LK}=\left(x_{soll}-x\left(t\right)\right)\cdot \mathrm{<figure-callout\; id="1"\; label="K"\; filenames="DE202023002939U1\_0085.png"\; state="\{\{state\}\}">K</figure-callout>}1+\left({x^{\prime }}_{soll}-x^{\prime }\left(t\right)\right)\cdot \mathrm{<figure-callout\; id="2"\; label="K"\; filenames="DE202023002939U1\_0085.png"\; state="\{\{state\}\}">K</figure-callout>}2+\left({\phi }_{xsoll}-{\phi }_x\left(t\right)\right)\cdot K3+\left({{\phi }^{\prime }}_{xsoll}-{{\phi }^{\prime }}_x\left(t\right)\right)\\ \cdot K4\end{array}$$

with t the current time step of the control, u* _LK the manipulated variable of the control and x(t), x'(t), φ _x (t), φ' _x (t) the current measured and determined state variables.

The pole specification method and the LQ method are widely known from the state of the art, for example from Holger Lutz, Wolfgang Wendt “Pocketbook of Control Engineering”, Europa-Lehrmittel, 2021, ISBN 9783808558706 and Otto Föllinger, “Control Engineering”, Vde Verlag GmbH, 2022, ISBN 9783800755189 .

Furthermore, a state space representation for a direction of motion in the tangential direction (y-direction or θ-direction) can correspond to $$\left[\begin{array}{c}{\theta }^{\prime }\\ {\theta }^{″}\\ {{\phi }^{\prime }}_y\\ {{\phi }^{″}}_y\end{array}\right]=A_{DW}\left[\begin{array}{c}\theta \\ {\theta }^{\prime }\\ {\phi }_{{}_y}\\ {{\phi }^{\prime }}_y\end{array}\right]+b_{DW}{u}_{DW}$$

$$b_{DW}=\left[\begin{array}{c}0\\ b3\\ 0\\ b4\end{array}\right]$$

An example parameterization of the system matrix A _DW and the input vector b _DW is as follows: $$A_{DW}=\left[\begin{array}{cccc}0& 1& 0& 0\\ 0& a4& 0& 0\\ 0& 0& 0& 1\\ 0& a5& a6& 0\end{array}\right]$$

$$b_{DW}=\left[\begin{array}{c}0\\ b3\\ 0\\ b4\end{array}\right]$$

wobei θ der Position des Aufhängungspunkts, φ_y dem Pendelwinkel in tangentialer Richtung, I_A einem vorgegebenen, insbesondere von einer Masse des Lastsystems abhängigen, I_A ein auf das Drehwerk wirkendes Trägheitsmoment, m der Masse des Lastsystem, und u_DW einer Eingangsgröße (vorzugsweise einer Geschwindigkeit) für das Drehwerk, d.h. einer Antriebseinrichtung für eine Bewegung des Aufhängungspunkts in tangentialer Richtung, entsprechen. A_DW entspricht einer 4x4 System-Matrix und b_DW einem Eingangsvektor mit Zustandsraumparametern der Zustandsraumdarstellung für die tangentiale Bewegung des Aufhängungspunktes. Auch andere Parametrisierungen der System-Matrix und des Eingangsvektors sind möglich.And for example: $$\left[\begin{array}{c}{\theta }^{\prime }\\ {\theta }^{″}\\ {{\phi }^{\prime }}_y\\ {{\phi }^{″}}_y\end{array}\right]=\left[\begin{array}{cccc}0& 1& 0& 0\\ 0& \frac{mxg}{\mathrm{<figure-callout\; id="0"\; label="l\; l\; A"\; filenames="DE202023002939U1\_0087.png"\; state="\{\{state\}\}">l</figure-callout>}{l}_A{}_{}}& 0& 0\\ 0& 0& 0& 1\\ 0& \left(\frac{m{x}^{2}g}{l{l}_A}+\frac{g}{l}\right)& -\frac{g}{l}& 0\end{array}\right]\left[\begin{array}{c}\theta \\ {\theta }^{\prime }\\ {\phi }_y\\ {{\phi }^{\prime }}_y\end{array}\right]+\left[\begin{array}{c}0\\ \frac{1}{l_A}\\ 0\\ \frac{x}{l{l}_A}\end{array}\right]u_{DW}$$

where θ is the position of the suspension point, φ _y is the pendulum angle in the tangential direction, I _A is a predetermined moment of inertia, which depends in particular on a mass of the load system, I _A is a moment of inertia acting on the slewing gear, m is the mass of the load system, and u _DW is an input variable (preferably a speed) for the slewing gear, i.e. a drive device for a movement of the suspension point in the tangential direction. A _DW corresponds to a 4x4 system matrix and b _DW is an input vector with state space parameters of the state space representation for the tangential movement of the Suspension point. Other parameterizations of the system matrix and the input vector are also possible.

mit t dem aktuellen Zeitschritt der Regelung, u*_DW der zu stellenden Stellgröße der Regelung und θ(t), θ'(t), φ_y(t), φ'_y(t) den aktuellen gemessenen und ermittelten Zustandsgrößen.By applying the pole specification method or the LQ method, a y-direction related control vector Ky= [K5, K6, K7, K8] ^T can be obtained for a control equation applied to the movement of the suspension point: $$\begin{array}{l}{u}^{\ast }{}_{DW}=\left({\theta }_{soll}-\theta \left(t\right)\right)\cdot K5+\left({{\theta }^{\prime }}_{soll}-{\theta }^{\prime }\left(t\right)\right)\cdot \mathrm{<figure-callout\; id="6"\; label="K"\; filenames="DE202023002939U1\_0085.png"\; state="\{\{state\}\}">K</figure-callout>}6+\left({\phi }_{ysoll}-{\phi }_y\left(t\right)\right)\cdot K7+\left({{\phi }^{\prime }}_{ysoll}-{{\phi }^{\prime }}_y\left(t\right)\right)\\ \cdot K8\end{array}$$

with t the current time step of the control, u* _DW the control variable to be set and θ(t), θ'(t), φ _y (t), φ' _y (t) the current measured and determined state variables.

This also makes it possible to easily adapt the state control to different crane configurations by selecting a manageable number of control parameters. The state control can be based on a state vector Z, which includes the load position and the load speed (relative to the suspension point), i.e., a load deflection and a load deflection speed and/or the oscillation angle and the oscillation angular speed in one or two lateral directions of movement. The state vector Z can further include information on the current setting position and adjustment speed of the relevant control element, i.e., the boom, the trolley, and the like, in the relevant x- or y-direction. The current adjustment speed in the x-direction corresponds to or is dependent on, for example, a luffing speed of the boom in a mobile crane or a trolley speed in a tower crane, and in the y-direction, a rotation angular speed of the boom. Accordingly, for example, the setting position corresponds to the luffing angle or the position of the trolley on the boom for the x-direction and the rotation angle for the y-direction.

It can be provided that the state control is operated in order to implement a sway damping function, in particular when a manual or automated crane operation specifies a speed of the suspension point for at least one of the directions of movement, wherein for the purpose of sway damping a target specification of the information on the load position and the load speed of the center of mass of the load system is specified as zero, the target specification for the speed of the suspension point is specified as zero and the target specification for a position of the suspension point is specified as a position determined depending on the specified speed of the suspension point.

With active state control, sway damping is achieved by specifying a load position and a load speed of φ _xsoll , φ _ysoll = 0, φ' _xsoll , φ' _ysoll , i.e. by specifying a load deflection of 0 and a load deflection speed of 0 and/or by specifying a sway angle of 0 and a sway angular speed of 0. This means that the control objective is that there is no relative movement of the center of mass of the load system to the suspension point and that the center of mass is exactly perpendicular below the suspension point.

The target value x' _target , θ' _target for the speed of the suspension point corresponds to a manually or automatically specified target value and is equal to zero, while the target value for the position of the suspension point is determined depending on the speed of the suspension point specified by the crane operation. The target position of the suspension point can thus be determined by the temporal accumulation of distance increments, each of which corresponds to the product of the target speed specified by the crane operation and the control cycle duration, in order to avoid overshoot when the end position is reached. For example, when operated by the crane operator, a movement speed of the luffing of the boom or trolley in the x-direction and/or by rotating the boom in the y-direction can be specified in order to move the load according to the operator's wishes.

The target specification can be made by input using a joystick or the like and corresponds to a desired adjustment speed of a corresponding drive device, in particular in the form of a motor speed of the drive device in the form of a slewing gear and/or a trolley, etc. The target specification of the speed can indirectly specify the control variables for the movement of the suspension point via the control system or, according to a mechanical coupling, by means of a step-up or step-down gear according to a predefined coupling function (known for the crane configuration).

By specifying target states, various operating functions can be implemented. In the sway damping function during ongoing crane operation, the adjustment speed (x and/or y direction) specified by the crane operator is cyclically accumulated to a target value for the position of the suspension point in the x and/or y directions x _target , θ _target depending on the control cycle duration. In this case, no target value is assumed for the speed of the suspension point x' _target , θ' _target .

The sway control function is active during crane operation. Crane operation is characterized by one of the target values being other than zero, or by a control element being operated to move the crane. The sway control function can remain active as long as a predetermined follow-up time has not yet elapsed after a control element is no longer operated.

The implementation of the state control enables the implementation of additional comfort functions for the operation of the jib crane.

As described above, the control is only executed during active crane operation and ends after a predetermined run-on time after the operator is no longer in control or after the automatic control of a crane movement has ended. However, it may happen that a residual sway remains after the crane operation has ended and after the state control has been deactivated, for example due to interference or the like. In this regard, by actively actuating the first control element by a crane operator or by another construction site employee who has an appropriate communication link with the crane control unit, the sway damping function can be activated for a predetermined period of time even when the jib crane is stationary, whereby the target state variables of the load position and the load speed, i.e., the sway angle and the sway angular speed or the load deflection and the load deflection speed, are set to zero. After actuation of the first control element, the state control remains active for a predetermined follow-up time of between 5 and 20 s or until the load position and the load speed indicate no load movement for a certain period of time, e.g. between 1 s and 5 s, or indicate a load movement of less than a predetermined threshold value.

Furthermore, after actuating the corresponding first control element, a peak position of the pendulum oscillation can be determined in a conventional manner and set as the target position. Furthermore, the follow-up time of the active state control can be set according to the oscillation period, whereby the follow-up time can be set according to half the period.

It can be provided that the state control is operated or operable to implement a disturbance compensation function, wherein the disturbance compensation function is continuously provided with a target specification of the information on the position of the suspension point, which is determined as a function of a stored absolute position of the load, and a target specification of the speed of the suspension point of zero, and the load position and the load speed of the center of mass of the load system are disregarded, in particular by setting the corresponding control deviations of the load position and the load speed of the center of mass of the load system to zero while the disturbance compensation function is activated, wherein in particular the target specification of the information on the position of the suspension point is determined based on the current load position of the center of mass, a pendulum length of the load system and the current position of the suspension point.

A disturbance compensation function can therefore be provided as a further alternative or additional operating function. When the disturbance compensation function is activated, e.g. by operating a second control element, the current absolute position of the load can be specified or saved as a target position. The current absolute position of the load is determined as the position of the suspension point on the boom at the time the disturbance compensation function is activated and the current load position in the form of a deflection from the vertical by adding them in one or both lateral directions, whereby the absolute position of the load is calculated using the load deflection or the pendulum angle, e.g. by applying trigonometric functions. Control then takes place according to the target specifications for an absolute position of the suspension point, which are cyclically adapted to the respective load position of the center of mass of the load system and the corresponding load speed. The load position and the load speed are not taken into account in the control, in particular by setting the corresponding control deviation or the associated element (factor) of the control vector K to zero during the activated disturbance compensation function.

The disturbance compensation function can be manually activated and deactivated. The disturbance compensation function can be automatically deactivated when active crane operation is requested, as the active sway control procedure is then activated and a stored absolute position of the load system's center of mass is no longer to be maintained.

It can be provided that the state control is operated or operable to carry out a positioning function, wherein the state control is given the information on the relative position and the relative speed of the center of mass of the load system as target specifications of zero and the position and the speed of the suspension point are disregarded, in particular by setting the corresponding control deviations during the activated positioning function or the associated element (factor) of the control vector K to zero.

According to the positioning function, upon actuation of a suitable third control element, in particular by a construction site employee who is connected to the control unit of the jib crane via a mobile control device, a control of the load position and load speed of the center of gravity of the load system can be activated, whereby no control is carried out for the position of the suspension point. Thus, only the load position (load deflection or the pendulum angle) and the load speed (load deflection speed or the pendulum angle speed), each of which is zero, are controlled. While the third control element, which is preferably designed as a touch element, is kept active, the load or the load handling device can be moved manually. By exerting a lateral force on the load handling device or the load, the active positioning function causes the load handling device to be displaced laterally, since the active state control attempts to control the load position (load deflection or pendulum angle), which deviates from zero due to the lateral force, back to the target value of zero. This moves the corresponding drive devices so that the compensating movement occurs in the direction of the force exerted on the load-handling device. After deactivating or releasing the third control element, the sway damping control described above can be activated for a specified period of time, for example, between 5 and 20 seconds, to reduce any remaining residual vibrations.

It can be provided that the state control is operated or operable to implement a load lifting function when a load is to be lifted, wherein the information on the load position is determined when a lifting force on the hoisting rope exceeds a predetermined lifting force threshold value and the load has not yet been lifted, wherein the state control is carried out with target specifications for the load position and the load speed and a speed of the suspension point of zero, wherein the control deviation for the position of the suspension point is not taken into account, in particular by setting the corresponding control deviations or the associated element (factor) of the control vector K to zero during the activated load lifting function.

In particular, the load lifting function can be activated when the suspended load is lifted during ongoing crane operation. In practice, it is common for the center of mass and the suspension point of the hoist rope to be not exactly vertical when the load is suspended. When the load is lifted, a significant pendulum movement would occur due to a relative position of the center of mass of the load system that is not equal to zero. Therefore, before the load is lifted, the hoist rope is first tightened until it is taut. Tension in the hoist rope can be detected by monitoring an increase in force on the hoist rope during a tightening process. Active state control when the load has not yet been lifted now results in the load position deviating from zero (the deflected pendulum angle or the detected load deflection) being compensated for and the control deviation regarding the pendulum angle/load deflection becoming zero. This positions the suspension point on the boom exactly above the center of mass of the load system, and when this is achieved, the load can be lifted without any pendulum swing occurring. Specifically, the lifting of the load is delayed until the pendulum angle is controlled to zero.

Furthermore, the state control can be operated or operable to implement a position approach function, in which a stored absolute position of the load is approached and the load is brought to a standstill there, wherein an absolute position of the load is stored according to a user request, wherein the state control is carried out with a target specification for the position of the suspension point that corresponds to the stored position, a target specification for the speed of the suspension point of zero, a target specification for the position and the speed of the center of mass of zero, as soon as the position of the suspension point changes during ongoing crane operation of the stored position of the suspension point, in particular below a predetermined threshold distance.

According to the position approach function, which is activated by operating a fourth control element, a specific position can be approached in one or more directions of movement, i.e., in the x and/or y directions. This activates the crane control, and the load is moved according to the crane control. If the current position approaches the stored position, the load is stopped at the stored position and the function is then deactivated. This allows the load to continue moving in any direction after stopping at the stored load position. As soon as the threshold distance is exceeded again, the position approach function can be reactivated.

The position approach function is based on state control for the x-direction and/or the y-direction by monitoring the distance between the suspension point position and the stored suspension point position. If the distance falls below a specified threshold, the manually or automatically specified target speed of the suspension point is set to zero and the stored load position is used as the target. The load position (oscillation angle or load deflection) and the load speed (oscillation angular speed or relative load speed) are then also set to zero. Thus, by saving the suspension point position, a limit is set that cannot be exceeded during ongoing crane operation without first stopping the load at the relevant position or limit. The stored position can be deleted by deactivating the position approach function.

According to a corridor function, a movement trajectory can be specified as a sequence of target load positions along which the movement of the suspended load is controlled or controllable. For example, the movement trajectory can be specified based on a tolerance-based trajectory of load positions, e.g., as a range of absolute load positions within which movement of the load is permitted. If the load reaches an absolute position at the limit of the specified movement range, the movement of the load is stopped and the load is guided along the limit of the movement range, so that the load moves along a boundary area. In this way, prohibited areas can be avoided if a prohibited area lies on the direct travel path between the start position and the target position.

• - Erfassen von Zustandsgrößen des Zustandsvektors, der Angaben zu einer Position und einer Geschwindigkeit eines bewegbaren Aufhängungspunkt, an den ein Lastsystem, das ein Hubseil, eine an einem unteren Ende des Hubseils angeordnete Lastaufnahmeeinrichtung und eine unterhalb der Lastaufnahmeeinrichtung angehängte Last umfasst, angehängt ist, und Angaben zu einer Lastposition und einer Lastgeschwindigkeit eines Masseschwerpunkts des Lastsystems bezüglich des Aufhängungspunkts umfassen,
• - Ermitteln mindestens einer Stellgröße zur Bewegung des Aufhängungspunktes in der zumindest einen Bewegungsrichtung basierend auf der Zustandsregelung;
• - Ansteuern des Auslegerdrehkrans abhängig von der mindestens einen Stellgröße.

According to a further aspect, a device, in particular a control device, for operating a jib crane with the aid of a state control can be provided, wherein the state control effects a control of a movement of a suspended load at least in one direction of movement and is based on a state vector, wherein the device is designed to:

• - Recording state variables of the state vector, which includes information on a position and a speed of a movable suspension point to which a load system comprising a hoist rope, a load-handling device arranged at a lower end of the hoist rope and a load suspended below the load-handling device is attached, and information on a load position and a load speed of a center of mass of the load system with respect to the suspension point,
• - Determining at least one manipulated variable for moving the suspension point in the at least one direction of movement based on the state control;
• - Control of the jib crane depending on at least one control variable.

According to a further aspect, the method according to the invention can be implemented by means of a control unit on the jib crane, wherein a computer program product is used in the control unit to carry out the method, on the basis of which computer program product the control unit receives commands to carry out the individual method steps, by means of which the aforementioned advantageous technical effects are achieved in order to enable the previously described functions on the jib crane.

According to a further aspect, a jib crane is provided, comprising one or more drive devices for moving a suspension point for a load system and the above device, wherein the jib crane is controlled by controlling the one or more drive devices.

Brief description of the drawings

• 1 eine schematische Darstellung eines Turmdrehkrans;
• 2 und 3 Darstellungen des Lastsystems als Mehrfach- bzw. Einfachpendel;
• 4 eine schematische Darstellung des Steuergeräts zum Betreiben des Turmdrehkrans der 1;
• 5 ein Flussdiagramm zur Veranschaulichung einer Pendeldämpfungsfunktion;
• 6 ein Flussdiagramm zur Veranschaulichung einer Störgrößenausgleichsfunktion;
• 7 ein Flussdiagramm zur Veranschaulichung einer Positionierfunktion;
• 8 ein Flussdiagramm zur Veranschaulichung einer Lastabhebefunktion;
• 9 ein Flussdiagramm zur Veranschaulichung einer Positionsanfahrfunktion.

Preferred embodiments are described in more detail below in conjunction with the following figures. They show:

• 1 a schematic representation of a tower crane;
• 2 and 3 Representations of the load system as a multiple or single pendulum;
• 4 a schematic representation of the control unit for operating the tower crane of the 1 ;
• 5 a flow chart illustrating a pendulum damping function;
• 6 a flowchart illustrating a disturbance compensation function;
• 7 a flowchart illustrating a positioning function;
• 8 a flowchart illustrating a load lifting function;
• 9 a flowchart illustrating a position approach function.

Description of embodiments

1 shows a schematic side view of a tower crane 2 for lifting, moving and setting down a load L. The tower crane 2 represents an example of a jib crane in the sense of this description. The tower crane 2 comprises a tower T which is at least partially fixed to a base G and has an imaginary vertical axis H and a trolley jib KA projecting from the tower T. The trolley jib KA is in the 1 Not designed to be luffing. In an example not shown, the trolley boom KA can also be designed to be luffing, with the luffing trolley boom KA being moved by means of a luffing drive.

The tower crane 2 comprises a slewing gear DW arranged on the rotation axis for rotating at least the trolley boom KA about the vertical axis H. The tower crane 2 comprises a rotation angle sensor device 510, designed, for example, as a rotation angle sensor, for determining a rotation angle θ_u of the trolley boom KA about the vertical axis H in an xy plane. The xy plane is generally defined as a tangential y-direction and a radial x-direction.

A trolley LK, which can be moved along the trolley boom KA, comprises a first and a second deflection pulley 202, 204 for deflecting a hoist rope HSL toward a load-handling device UF, which can be designed as a bottom block or hook block. The load-handling device UF comprises at least one deflection pulley 302 for the hoist rope HSL, but can also comprise a plurality of deflection pulleys for the hoist rope HSL.

The hoist rope HSL is guided from a hoisting gear HW for winding and unwinding the hoist rope HSL over the first deflection pulley 202 of the trolley LK, a deflection pulley 302 of the load handling device UF, and the second deflection pulley 204 of the trolley LK. The hoist rope HSL is attached to a distal section 4 of the trolley boom KA.

The hoisting gear HW can, as is known per se, comprise a brake, an electric motor, a gearbox, and a cable winch. The hoisting rope HSL is wound onto the cable winch of the hoisting gear HW to raise the load L, and it is unwound to lower the load L. The hoisting rope HSL is guided, for example, from the hoisting gear via two deflection pulleys 20 and 22 arranged at or near the vertical axis H to the deflection pulley 202 of the trolley LK.

A hoist rope length I ₁ is determined using a hoist rope length sensor 610, for example in the form of a rotation angle sensor that counts the revolutions of the hoist HW. For example, by detecting the rotational position of the hoist HW, the distance between the load handling device UF and the trolley LK and the suspension point AUP can be determined, which is assumed to be the hoist rope length I ₁ .

A mass sensor device 620 is according to 1 coupled to the deflection pulley 22 and detects the mass m of the suspended load L or the load system at a suspension point AUP on the trolley LK. The mass sensor device 620 measures, for example, a tensile force exerted on the deflection pulley 22. A sensor signal determined by the sensor device 620 represents the mass m.

A first angle sensor device 210 arranged on the trolley LK is configured to determine a respective hoist rope angle φ _1y , φ _1x (in the y-direction and in the x-direction) of one or more sections HSL#1, HSL#2 of the hoist rope HSL located between the trolley LK and the load handling device UF, relative to the perpendicular passing through the suspension point AUP. The first angle sensor device 210 can, for example, have a distance measuring system (optical or ultrasonic-based) that measures distances, dependent on the hoist rope angle, between the first angle sensor device 210 and a section of the hoist rope HSL and derives the hoist rope angle φ _1y , φ _1x (in the y-direction and in the x-direction) therefrom. Other known measuring methods for determining the hoist rope angle φ _1y , φ _1x are also applicable. The hoist rope angle φ _1y , φ _1x (in the y-direction and in the x-direction) corresponds to an angle of the distance between the suspension point AUP and a center of mass of the load-handling device UF to the vertical line through the suspension point AUP. The first angle sensor device 210 is connected to a control unit 100 to provide information about the respective hoist rope angle φ _1y , φ _1x .

A second angle sensor device 310, arranged on the load-handling device UF and designed, for example, as a gyroscope, is configured to determine a load cable angle φ2x, φ2y in the x-direction or y-direction to the perpendicular passing through the attachment point ANP of the load L to the load-handling device UF. The load cable angle φ2x, φ2y indicates the angle between the distance between the attachment point ANP and the center of mass of the attached load and the perpendicular through the attachment point ANP in the x-direction or y-direction. The second angle sensor device 310 is in communication with the control unit.

For example, a load rope length I ₂ of the load rope LSL or, in the case of other lifting gear, a distance between the load suspension device UF and the center of mass of the load L is preset or can be determined by a user. Alternatively, this can also be measured using a suitable measuring device.

A trolley KW, fixed to the trolley jib KA, is connected to the trolley LK by a trolley cable KSL for its movement along the trolley jib KA. The trolley KW comprises a brake, an electric motor, a gearbox, and a double cable winch. The double cable winch comprises two sections connected by a common axle. When the double cable winch rotates in one direction, the axle winds up one part of the trolley cable KSL and unwinds the other part, thus moving the trolley LK.

A position sensor device 420, for example, a rotation angle sensor that counts the revolutions of the trolley KW, is arranged fixedly to the frame 402. This sensor device generates a sensor signal that indicates the position x of the trolley LK. The position x of the trolley LK corresponds to the position of the suspension point AUP.

An angle difference sensor device 410 is configured to determine a rotation angle difference Δθ between the rotation angle θ_u of the trolley boom KA about the vertical axis H and a current rotation angle θ of the position of the trolley LK about the vertical axis H. The angle difference sensor device 410 for determining the rotation angle difference Δθ is arranged fixedly to the trolley boom KA, in particular on the trolley boom KA or on a frame 402 of the trolley chassis KW. The angle difference sensor device 410 can be configured, for example, to determine, using ultrasonic measurement technology, a lateral distance between the angle difference sensor device 410 and a section KSL#1 of the trolley cable KSL, which is located between a deflection pulley 6 proximal to the trolley boom KA and the trolley LK. A deflection pulley 8 arranged distally to the trolley boom KA deflects the trolley cable KSL from the trolley undercarriage KW to the trolley LK. The rotation angle difference Δθ can then be determined either in the angle difference sensor device 410 or in the control unit 100 as a function of the sensor signal representing the distance. Other known options for determining the rotation angle difference Δθ are also applicable. The angle difference sensor device 410 serves to determine the rotation angle θ_u of the trolley boom KA, which deviates from the actual rotation angle θ of the trolley LK or a suspension point AUP of the load system due to elastic deformation of the trolley boom KA.

The trolley KW comprises the frame 402 and a drive unit arranged fixedly to the frame 402 for winding and unwinding a trolley rope KSL. The angle difference sensor device 410 arranged fixedly to the frame 402 is configured to determine the angle of rotation difference Δθ between a rotation angle θ_u of the trolley jib KA about a vertical axis H of a tower T of the tower crane 2 and a current angle of rotation θ of the trolley LK or the suspension point AUP about the vertical axis H.

Another inclination sensor device 220, which is arranged fixedly on the trolley LK, in particular in relation to its chassis and is designed, for example, as a gyroscope, serves to determine an inclination angle Δφ (rocking angle difference) of the trolley LK to a horizontal plane. The inclination sensor device 220 determines a sensor signal which characterizes an inclination of the trolley LK to a horizontal plane, in particular an inclination angle to a horizontal plane lying in an xh plane spanned by the vertical axis h and the longitudinal axis x of the trolley boom KA. The control unit 100 can take the inclination angle Δφ into account as a correction for calculating the current hoist rope angle φ _1x in the x direction in order to determine the hoist rope angle φ _1x to the perpendicular through the suspension point AUP. This is necessary because, as a rule, the first angle sensor device 210 tilts with the trolley LK and does not detect this angle error when measuring the hoist rope angle φ _1x .

The control unit 100 is designed as a conventional data processing device and carries out a method to operate the slewing gear DW, the hoisting gear HW and the trolley KW depending on all or part of the following variables: the angle of rotation θ_u, the angle of rotation difference Δθ, the hoisting rope angle φ _1x , φ _1y , the load rope angle φ _2y , φ _2x the hoisting rope length I ₁ , the load rope length I ₂ , the mass of the suspended load, the position x of the trolley and the inclination angle Δφ.

To control the slewing gear DW, the hoisting gear HW, and the trolley KW, the motors provided therein are given control speeds u* _DW , u* _HW , u* _KW as control variables. In other embodiments, control can also be achieved by specifying a torque.

The hoist rope HSL suspended from the trolley LK, the load suspension device UF, the load rope LSL, and the load L form a load system. The load system represents a multiple pendulum, whose suspension point AUP is assumed to be between two sections HSL#1, HSL#2 of the hoist rope HSL. The multiple pendulum is described in the following 2 and 3 explained and comprises the two sections HSL#1, HSL#2 of the hoist rope HSL, the load suspension device UF hanging on the hoist rope HSL, a load rope LSL arranged below the load suspension device UF and the load L arranged on the load rope LSL. In this context, a multiple or double pendulum is understood to mean the load system located below the trolley LK or below the deflection pulleys 202, 204 of the trolley LK.

An operating unit 900 is provided for crane operation. The operating unit 900 is configured, for example, as a control panel in the crane operator's cab and/or as a radio remote control that communicates with the control unit 100. Using, for example, a joystick 910 of the operating unit 900, target values S _target can be implicitly transmitted to the control unit 100, which indicate a movement speed in the x-direction and/or in the y-direction. Furthermore, the lifting or lowering of the load using the hoist HW can be specified by the user in the form of a target value. The target values include u* _LKsoll , u* _DWsoll , and/or u* _HWsoll , and can specify actuating speeds for the motors of the trolley KW, the slewing gear DW and/or the hoist HW and can be converted into corresponding movements of the suspension point AUP and a change in the hoist rope length I ₁ according to the mechanical design in a known manner in order to obtain target values x' _soll , θ' _soll , and/or I' _soll . The target values can also be specified directly as x' _soll , θ' _soll , and/or I' _soll .

2 shows a schematic illustration of the tower crane from the 1 existing double pendulum. In this double pendulum, which is formed by the sections HSL#1, HSL#2 of the hoist rope HSL, the load suspension device UF, the load rope LSL and the load, two relevant angles arise in one direction: the hoist rope angle φ ₁ at the suspension point AUP in relation to the vertical through the suspension point AUP and the load rope angle φ ₂ at the suspension point ANP in relation to the vertical through the suspension point ANP.

3 shows the simplification of the multiple pendulum proposed in this description to prevent or reduce pendulum motion. The multiple pendulum from 2 is regarded as a single pendulum for the state control described below. A relevant parameter here is the pendulum angle φ of the deflection of the load L relative to the trolley LK. This is difficult to measure directly using robust sensors. For one direction, the pendulum angle φ is therefore calculated using the hoist rope angle φ ₁ , the hoist rope length I ₁ , the load rope length I ₂ and the load rope angle φ ₂ , which are obtained as described above. To compensate for the hoist rope angle φ _1x in the x-direction, the angle of inclination Δφ of the trolley boom KA to the horizontal can be taken into account, so that the hoist rope angle φ _1x in the x-direction is φ _1x .= φ ₁ + Δφ This correction is not necessary for the hoist rope angle φ _1y in the y-direction.

Due to the assumed significantly higher mass of the load L compared to the mass of the load handling device UF, the inclination of the load handling device UF corresponds to the deflection of the attached load and thus φ ₂ , i.e. φ _2x for the x-direction and φ _2y for the y-direction.

4 shows in reference to 1 the signal flow for the determination of control variables in the form of control speeds u* _LK , u* _DW , u* _HW to be set for the trolley LK, the slewing gear DW or the hoist HW by the control unit 100. The respective control speed can be specified, for example, in % of the maximum speed (nominal speed) for the respective drive motor (trolley KF, the slewing gear DW and the hoist HW).

The pendulum angle φ _x , φ _y in x- and y-direction can be calculated with reference to 4 in a pendulum angle calculation block 110 in the control unit 100 in different ways.

In an exact calculation, the length I of the double pendulum is $$l=\sqrt{{\left(l_{1}cos\left({\phi }_{1x}\right)+l_{2}cos\left({\phi }_{2x}\right)\right)}^2+{\left(l_{1}sin\left({\phi }_{1x}\right)+l_{2}sin\left({\phi }_{2x}\right)\right)}^2}$$

$${\phi }_y=arcsin\left(\frac{\left(l_{1}sin\left({\phi }_1{}_x\right)+l_{2}sin\left({\phi }_{2x}\right)\right)}{l}\right)$$

And the pendulum angles φ _x , φ _y in x-direction and y-direction respectively to $${\phi }_x=arcsin\left(\frac{\left(l_{1}sin\left({\phi }_{1x}\right)+l_{2}sin\left({\phi }_{2x}\right)\right)}{l}\right)$$

$${\phi }_y=arcsin\left(\frac{\left(l_{1}sin\left({\phi }_1{}_x\right)+l_{2}sin\left({\phi }_{2x}\right)\right)}{l}\right)$$

$${\phi }_x=k_x{\phi }_{1x}+\left(1-k_x\right){\phi }_{2x}$$

$${\phi }_y=k_y{\phi }_{1y}+\left(1-k_y\right){\phi }_{2y}$$

wobei die Faktoren k_x und k_y als Konstanten, insbesondere in einem Bereich zwischen 0,25 - 0,75, oder gemäß einem Kennfeld oder einer Funktion abhängig von der Hubseillänge I₁ und/oder einer Masse der angehängten Last L vorgegeben werden können, z.B. als $k_x=k_y=\frac{l_1}{l_1+l_2}.$

$$

This calculation can be simplified by approximation in the form of a sensor fusion with $$l={\mathrm{<figure-callout\; id="1"\; label="l"\; filenames="DE202023002939U1\_0085.png"\; state="\{\{state\}\}">l</figure-callout>}}_1+{\mathrm{<figure-callout\; id="2"\; label="l"\; filenames="DE202023002939U1\_0085.png"\; state="\{\{state\}\}">l</figure-callout>}}_2$$

$${\phi }_x=k_x{\phi }_{1x}+\left(1-k_x\right){\phi }_{2x}$$

$${\phi }_y=k_y{\phi }_{1y}+\left(1-k_y\right){\phi }_{2y}$$

where the factors k _x and k _y can be specified as constants, in particular in a range between 0.25 - 0.75, or according to a characteristic map or a function depending on the hoist rope length I ₁ and/or a mass of the suspended load L, e.g. as $k_x=k_y=\frac{l_1}{{\mathrm{<figure-callout\; id="1"\; label="l"\; filenames="DE202023002939U1\_0085.png"\; state="\{\{state\}\}">l</figure-callout>}}_1+{\mathrm{<figure-callout\; id="2"\; label="l"\; filenames="DE202023002939U1\_0085.png"\; state="\{\{state\}\}">l</figure-callout>}}_2}.$

$$

At least the above sensor variables and target variables S _target are supplied to the control unit 100 in order to determine the actuating speeds u* _LK , u* _DW , u* _HW according to a state control 120. The target variables can include a target speed u* _{KW target} or a target torque for the trolley KW, a target speed u* _DW target or a target torque for the slewing gear DW and a target speed u* _{HW target} or a target torque for the hoist HW.

Furthermore, a function block 130 is provided which controls the operation of the state control 120, in particular depending on an operation of the control unit 900, so that various operating functions can be realized.

In a rotation angle calculation block 140, the rotation angle θ determined by the rotation angle sensor device 510 and the rotation angle difference Δθ measured by the angle difference sensor device 410 are added and a corrected rotation angle θ for an actual rotation angle of the trolley boom KA about the vertical axis H is provided.

Using suitable derivative blocks 150, 160, 170, 190, the time derivatives for the pendulum angles φ _x , φ _y , the corrected angle of rotation θ and the speed x' of the suspension point AUP can be formed as φ' _x , φ' _y , θ' and x'.

Furthermore, the position x of the trolley LK (as the position of the suspension point AUP) is provided to the state controller by the position sensor device 420. Using the derivation block 190, a trolley speed x' (as the speed of the suspension point AUP) can be provided to the state controller 120 as a time derivative. Alternatively, the trolley speed x' can be read directly from the control unit 900, because it is available there very accurately given a known (measured) motor speed and a known transmission ratio.

A control parameter block 180 is provided to determine control parameters in the form of a control vector Kx=[K1, K2, K3, K4] T , Ky=[K5, K6, K7, K8] T for the respective direction of movement (x and/or y direction) from the constantly updated system matrix A and the input vector b, which is dependent on the mass m, the pendulum length _I and, if applicable, the position ^x of the trolley LK (or the suspension point), as a function of a mass m of the load system measured by the mass sensor device ⁶²⁰ , as a function of a position x of the trolley LK (or the suspension point), as a function of the position sensor device 420, and of a hoist rope length I 1 or the total pendulum length I of the multiple pendulum. The control parameters K are provided to the state controller 120.

The system matrix A and the input vector b are updated in the event of a change in at least one of the variables mass m, pendulum length I, and position x of the trolley LK (or the suspension point), in particular by more than a predetermined absolute or relative deviation value (e.g., 2%) according to a known determination method for state-space parameters. Using the system matrix A and the input vector b, the control parameter block 180 executes a known pole specification method or a method based on a known LQ method to determine the respective control vector Kx, Ky based on the state-space description.

The state control 120 can be described using a state-space representation. In the state-space representation, n-order linear systems are decomposed into n first-order subsystems to enable simple control parameterization. The state controls for the trolley KW and the slewing gear DW can be considered separately.

In the state control for the trolley KW, the pendulum angle φ _x in the x-direction, its pendulum angular speed φ' _x , the position x of the trolley and the speed x' of the trolley LK are taken into account as state variables.

The task of state control is to calculate the manipulated variables u* LK , u* DW , u* _HW from the state variables of the state variable vector Z and the specified target variables Ssoll = u* _KWsoll , u* _DWsoll , u* _HW or, if necessary, after appropriate conversion _x ' _soll , θ _{' soll} , I' _soll . The control deviations of the state variables are multiplied by the respectively updated control parameters from the control vectors Kx, Ky. The sum of these products is then the respective desired manipulated variable.

wobei x'' der Beschleunigung der Laufkatze LK (d.h. des Aufhängungspunkts AUP) und cp''_X der Winkelbeschleunigung des Pendelwinkels entsprechen. A_LK entspricht einer 4x4 System-Matrix und b_LK einem Eingangsvektor mit Zustandsraumparametern der Zustandsraumbeschreibung für das Katzfahrwerk KW. Eine beispielhafte Parametrierung der System-Matrix A_LK und des Eingangsvektors b kann wie folgt lauten: $$A_{LK}=\left[\begin{array}{cccc}0& 1& 0& 0\\ 0& a1& 0& 0\\ 0& 0& 0& 1\\ 0& a2& a3& 0\end{array}\right]$$

$$b_{LK}=\left[\begin{array}{c}0\\ b1\\ 0\\ b2\end{array}\right]$$

The state space representation for the running gear LK is: $$\left[\begin{array}{c}{x}^{\prime }\\ x^{″}\\ {{\phi }^{\prime }}_x\\ {{\phi }^{″}}_x\end{array}\right]=A_{LK}\left[\begin{array}{c}x\\ x^{\prime }\\ {\phi }_x\\ {{\phi }^{\prime }}_x\end{array}\right]+b_{LK}{u}_{LK};$$

where x'' corresponds to the acceleration of the trolley LK (i.e., the suspension point AUP) and cp'' _X corresponds to the angular acceleration of the pendulum angle. A _LK corresponds to a 4x4 system matrix, and b _LK is an input vector with state-space parameters of the state-space description for the trolley KW. An example parameterization of the system matrix A _LK and the input vector b can be as follows: $$A_{LK}=\left[\begin{array}{cccc}0& 1& 0& 0\\ 0& a1& 0& 0\\ 0& 0& 0& 1\\ 0& a2& a3& 0\end{array}\right]$$

$$b_{LK}=\left[\begin{array}{c}0\\ \mathrm{<figure-callout\; id="1"\; label="b"\; filenames="DE202023002939U1\_0085.png"\; state="\{\{state\}\}">b</figure-callout>}1\\ 0\\ b2\end{array}\right]$$

Where a1, a2, a3, b1, b2 are system parameters for the control, which can be determined in a conventional manner, e.g., by physical modeling or empirically. By applying the pole specification method or the LQ method, the control vector K can be determined, resulting in the following calculation rule for the cyclic calculation of the manipulated variable u* _LK : $$\begin{array}{l}{u}^{\ast }{}_{LK}=\left(x_{soll}-x\left(t\right)\right)\cdot \mathrm{<figure-callout\; id="1"\; label="K"\; filenames="DE202023002939U1\_0085.png"\; state="\{\{state\}\}">K</figure-callout>}1+\left({x^{\prime }}_{soll}-x^{\prime }\left(t\right)\right)\cdot \mathrm{<figure-callout\; id="2"\; label="K"\; filenames="DE202023002939U1\_0085.png"\; state="\{\{state\}\}">K</figure-callout>}2+\left({\phi }_{xsoll}-{\phi }_x\left(t\right)\right)\cdot K3+\left({{\phi }^{\prime }}_{xsoll}-{{\phi }^{\prime }}_x\left(t\right)\right)\\ \cdot K4\end{array}$$

During normal operation with active sway damping, the desired speed u* _LKsoll of the trolley (i.e., of the suspension point AUP) is set by the control unit 900, in particular a joystick or the like, in the range from -100 to 100% of a predetermined nominal speed. This is converted into the speed x' of the trolley or of the suspension point AUP according to the mechanical coupling to the trolley or of the suspension point AUP.

In the state control for the slewing gear DW, the pendulum angle φ _y in the y-direction, its pendulum angular velocity φ' _y , the rotation angle θ of the trolley boom and the rotation angular velocity θ' of the trolley boom are taken into account as state variables.

wobei θ'' der Drehwinkelbeschleunigung und φ''_y der Winkelbeschleunigung des Pendelwinkels in y-Richtung entsprechen. A_DW entspricht einer 4x4 System-Matrix und b_DW einem Eingangsvektor mit Zustandsraumparametern der Zustandsraumbeschreibung für das Drehwerk DW. Eine beispielhafte Parametrierung der System-Matrix A_DW und des Eingangsvektors b_DW ist wie folgt: $$A_{DW}=\left[\begin{array}{cccc}0& 1& 0& 0\\ 0& a4& 0& 0\\ 0& 0& 0& 1\\ 0& a5& a6& 0\end{array}\right]$$

$$b_{DW}=\left[\begin{array}{c}0\\ b3\\ 0\\ b4\end{array}\right]$$

The state space representation for the slewing gear DW is: $$\left[\begin{array}{c}{\theta }^{\prime }\\ {\theta }^{″}\\ {{\phi }^{\prime }}_y\\ {{\phi }^{″}}_y\end{array}\right]=A_{DW}\left[\begin{array}{c}\theta \\ {\theta }^{\prime }\\ {\phi }_y\\ {{\phi }^{\prime }}_y\end{array}\right]+b_{DW}{u}_{DW}$$

where θ'' corresponds to the angular acceleration of the rotation and φ'' _y to the angular acceleration of the pendulum angle in the y-direction. A _DW corresponds to a 4x4 system matrix, and b _DW is an input vector with state-space parameters of the state-space description for the slewing gear DW. An example parameterization of the system matrix A _DW and the input vector b _DW is as follows: $$A_{DW}=\left[\begin{array}{cccc}0& 1& 0& 0\\ 0& a4& 0& 0\\ 0& 0& 0& 1\\ 0& a5& a6& 0\end{array}\right]$$

$$b_{DW}=\left[\begin{array}{c}0\\ b3\\ 0\\ b4\end{array}\right]$$

Where a4, a5, a6, b3, b4 are control parameters for the control, which can be determined in a conventional manner, e.g., by physical modeling or empirically. By applying the pole specification method or the LQ method, the control vector Ky = [K5, K6, K7, K8] ^T can be determined, resulting in the following calculation rule for the cyclic calculation of the manipulated variable u* _DW : $$\begin{array}{l}{u}^{\ast }{}_{DW}=\left({\theta }_{soll}-\theta \left(t\right)\right)\cdot K5+\left({{\theta }^{\prime }}_{soll}-{\theta }^{\prime }\left(t\right)\right)\cdot \mathrm{<figure-callout\; id="6"\; label="K"\; filenames="DE202023002939U1\_0085.png"\; state="\{\{state\}\}">K</figure-callout>}6+\left({\phi }_{ysoll}-{\phi }_y\left(t\right)\right)\cdot K7+\left({{\phi }^{\prime }}_{ysoll}-{{\phi }^{\prime }}_y\left(t\right)\right)\\ \cdot K8\end{array}$$

In normal operation with active sway damping, the desired rotation speed u* _DWsoll of the slewing gear is set by the control unit 900, in particular a joystick or the like, in the range from -100 to 100% of a given nominal speed. This is converted into the rotational angular velocity θ' of the trolley boom or an angular velocity of the suspension point AUP, depending on the mechanical coupling to the trolley or the suspension point AUP.

The state controller can also include the hoist HW and include the total pendulum length I and the pendulum length velocity I' as state variables. The control model can accordingly have the following structure: $$\left[\begin{array}{c}{x}^{\prime }\\ x^{″}\\ {{\phi }^{\prime }}_x\\ {{\phi }^{″}}_x\\ {\theta }^{\prime }\\ {\theta }^{″}\\ {{\phi }^{\prime }}_y\\ {{\phi }^{″}}_y\\ l^{\prime }\\ l^{″}\end{array}\right]=\left[\begin{array}{ccc}{A}_{LK}& A_{DW}\to {\mathrm{<figure-callout\; id="0"\; label="A\; L\; K"\; filenames="DE202023002939U1\_0087.png"\; state="\{\{state\}\}">A</figure-callout>}}_{LK}& \begin{array}{cc}0& 0\\ 0& 0\\ 0& 0\\ 0& 0\end{array}\\ \begin{array}{cccc}0& 0& 0& 0\\ 0& 0& 0& 0\\ 0& 0& 0& 0\\ 0& 0& 0& 0\end{array}& {\mathrm{<figure-callout\; id="0"\; label="A\; D\; W"\; filenames="DE202023002939U1\_0087.png"\; state="\{\{state\}\}">A</figure-callout>}}_{DW}& \begin{array}{cc}0& 0\\ 0& 0\\ 0& 0\\ 0& 0\end{array}\\ \begin{array}{cccc}0& 0& 0& 0\\ 0& 0& 0& 0\end{array}& \begin{array}{cccc}0& 0& 0& 0\\ 0& 0& 0& 0\end{array}& A_{HW}\end{array}\right]\left[\begin{array}{c}x\\ x^{\prime }\\ \phi {}_x\\ {\phi }^{\prime }{}_x\\ \theta \\ {\theta }^{\prime }\\ \phi {}_y\\ {\phi }^{\prime }{}_y\\ l\\ l^{\prime }\end{array}\right]+\left[\begin{array}{ccc}{\mathrm{<figure-callout\; id="0"\; label="b\; L\; K"\; filenames="DE202023002939U1\_0087.png"\; state="\{\{state\}\}">b</figure-callout>}}_{LK}& \begin{array}{c}0\\ 0\\ 0\\ 0\end{array}& \begin{array}{c}0\\ 0\\ 0\\ 0\end{array}\\ \begin{array}{c}0\\ 0\\ 0\\ 0\end{array}& {\mathrm{<figure-callout\; id="0"\; label="b\; D\; W"\; filenames="DE202023002939U1\_0087.png"\; state="\{\{state\}\}">b</figure-callout>}}_{DW}& \begin{array}{c}0\\ 0\\ 0\\ 0\end{array}\\ \begin{array}{c}0\\ 0\end{array}& \begin{array}{c}0\\ 0\end{array}& b_{HW}\end{array}\right]\left[\begin{array}{c}{u}_{LK}\\ u_{DW}\\ u_{HW}\end{array}\right]$$

The state control uses the setpoint variables u* _DWsoll , u* _LKsoll, and u* _HWsoll as setpoint specifications. The corresponding setpoint specifications for the control then correspond to the converted θ' _soll , x' _soll , and I' _soll , which result from converting the speeds of the drive devices DW, LW, and HW corresponding to the setpoint variables u* _DWsoll , u* _LKsoll , and u* _HWsoll (setpoint specifications) into the corresponding movement speeds of the slewing gear and the trolley KW in lateral directions (x, y) and of the load in the vertical direction (h).

The control system can follow a control cycle duration of between 10 ms and 500 ms. The control system can include an observer that calculates the state variables in advance for the next time step. Observer structures are known from the state of the art and will not be discussed in detail here.

• Für die x-Richtung: $$\begin{array}{l}{u}^{\ast }{}_{LK}=\left(x_{soll}-x\left(t\right)\right)\cdot \mathrm{<figure-callout\; id="1"\; label="K"\; filenames="DE202023002939U1\_0085.png"\; state="\{\{state\}\}">K</figure-callout>}1+\left({x^{\prime }}_{soll}-x^{\prime }\left(t\right)\right)\cdot \mathrm{<figure-callout\; id="2"\; label="K"\; filenames="DE202023002939U1\_0085.png"\; state="\{\{state\}\}">K</figure-callout>}2+\left({\phi }_{xsoll}-{\phi }_x\left(t\right)\right)\cdot K3+\left({{\phi }^{\prime }}_{xsoll}-{{\phi }^{\prime }}_x\left(t\right)\right)\\ \cdot K4\end{array}$$
  
• Für die y-Richtung: $$\begin{array}{l}{u}^{\ast }{}_{DW}=\left({\theta }_{soll}-\theta \left(t\right)\right)\cdot K5+\left({{\theta }^{\prime }}_{soll}-{\theta }^{\prime }\left(t\right)\right)\cdot \mathrm{<figure-callout\; id="6"\; label="K"\; filenames="DE202023002939U1\_0085.png"\; state="\{\{state\}\}">K</figure-callout>}6+\left({\phi }_{ysoll}-{\phi }_y\left(t\right)\right)\cdot K7+\left({{\phi }^{\prime }}_{ysoll}-{{\phi }^{\prime }}_y\left(t\right)\right)\\ \cdot K8\end{array}$$
  
  mit t dem aktuellen Zeitschritt der Regelung und x(t), x'(t), φ_x(t), φ'_x(t), θ(t), θ'(t), φ_y(t), φ'_y(t) den aktuellen gemessenen und ermittelten Zustandsgrößen.

In contrast to a conventional control system, an optimal trajectory of the control variables u* _LK , u* _DW , u* _HW (neutralizing any upswing leading to swaying motion) of the load is calculated based on the existing state variables, so that no strong swaying motion caused by the crane operator or crane operation can occur. Subsequent damping of the oscillating pendulum system is therefore not necessary. After activating the state control to perform a sway damping function by a corresponding target value Ssoll after lifting the load, the target values are converted into the corresponding target values θ' _soll , x' _soll and I' _soll according to the respective mechanical coupling between the trolley KW, the slewing gear DW and the hoist HW to the trolley LK, the trolley jib KA and the load handling device UF and taken into account in the control:

• For the x-direction: $$\begin{array}{l}{u}^{\ast }{}_{LK}=\left(x_{soll}-x\left(t\right)\right)\cdot K1+\left({x^{\prime }}_{soll}-x^{\prime }\left(t\right)\right)\cdot K2+\left({\phi }_{xsoll}-{\phi }_x\left(t\right)\right)\cdot K3+\left({{\phi }^{\prime }}_{xsoll}-{{\phi }^{\prime }}_x\left(t\right)\right)\\ \cdot K4\end{array}$$
  
• For the y-direction: $$\begin{array}{l}{u}^{\ast }{}_{DW}=\left({\theta }_{soll}-\theta \left(t\right)\right)\cdot K5+\left({{\theta }^{\prime }}_{soll}-{\theta }^{\prime }\left(t\right)\right)\cdot K6+\left({\phi }_{ysoll}-{\phi }_y\left(t\right)\right)\cdot K7+\left({{\phi }^{\prime }}_{ysoll}-{{\phi }^{\prime }}_y\left(t\right)\right)\\ \cdot K8\end{array}$$
  
  with t the current time step of the control and x(t), x'(t), φ _x (t), φ' _x (t), θ(t), θ'(t), φ _y (t), φ' _y (t) the current measured and determined state variables.

$$x{\text{'}}_{soll}=0$$

$${\phi }_{xsoll}=0$$

$$\phi {\text{'}}_{xsoll}=0$$

$${\theta }_{soll}=f\left(u_{DWsoll}\right)$$

$$\theta {\text{'}}_{soll}=0$$

$${\phi }_{ysoll}=0$$

$$\phi {\text{'}}_{ysoll}=0$$

The following applies to the sway damping function during crane operation: $$x_{soll}=f\left(u_{LKsoll}\right)$$

$$x{\text{'}}_{soll}=0$$

$${\phi }_{xsoll}=0$$

$$\phi {\text{'}}_{xsoll}=0$$

$${\theta }_{soll}=f\left(u_{DWsoll}\right)$$

$$\theta {\text{'}}_{soll}=0$$

$${\phi }_{ysoll}=0$$

$$\phi {\text{'}}_{ysoll}=0$$

$${\theta }_{soll}\left(t\right)=g\left(u{*}_{DWsoll}\right)=={\theta }_{soll}\left(\text{t}-1\right)+\theta {\text{'}}_{soll}\left(\text{t}-1\right)*\mathrm{\Delta }\text{t}$$

The functions for determining the target position of the suspension point correspond to $$x_{soll}\left(t\right)=f\left(u{*}_{LKsoll}\right)=x_{soll}\left(t-1\right)+x{\text{'}}_{soll}\left(t-1\right)*\mathrm{\Delta }\text{t}$$

$${\theta }_{soll}\left(t\right)=g\left(u{*}_{DWsoll}\right)=={\theta }_{soll}\left(\text{t}-1\right)+\theta {\text{'}}_{soll}\left(\text{t}-1\right)*\mathrm{\Delta }\text{t}$$

Where Δt is the control cycle duration, e.g., between 10 ms and 100 ms. Furthermore, the functions f() and g() can also consider ramp functions for the speeds to limit the rates of change of the specified variables.

The entire control system can be described by the above-mentioned state controller. The state controller is active at all times during tower crane operation and remains active for a specified overrun time after the end of an operating command to prevent any post-oscillation.

Alternatively, the control can also be applied to only one or two of the motion components, i.e., the movement of the trolley (i.e., x-movement of the suspension point AUP) (x-direction), the rotational movement of the trolley boom (i.e., y-movement of the suspension point AUP) (y-direction), or the movement of the hoist (h-direction). Accordingly, the considered states of the state control 120 are reduced by the respective quantities.

To utilize the sway damping function achieved by the state control, further additional functions for operating the tower crane can be implemented.

For this purpose, for example, a first operating element 920 can be provided on the operating unit 900, with which the user can dampen existing load or residual pendulum oscillations that occur after a load transport process according to a pendulum damping function. This pendulum damping function corresponds to the conventional pendulum damping function described above, which is activated upon actuation of the first operating element 920, which can be designed, for example, as a pushbutton switch, and remains active during a follow-up time of, for example, between 5 and 30 s, preferably between 5 and 15 s, in particular 10 s, after the end of actuation of the first operating element 920. The follow-up time can be fixed or depend on a current pendulum length I. Thus, the respective follow-up time can be variably specified by a function or a look-up table depending on the pendulum length I.

By providing the function of the first control element 920, the crane operator of the tower crane has the possibility of reducing a pendulum oscillation that occurs during inactive crane operation, i.e., no active transport movement takes place, e.g. due to a brief, sudden force acting on the load system.

$$x{\text{'}}_{soll}=0$$

$${\phi }_{xsoll}=0$$

$$\phi {\text{'}}_{xsoll}=0$$

$${\theta }_{soll}={\theta }_{store}$$

$$\theta {\text{'}}_{soll}=0$$

$${\phi }_{ysoll}=0$$

$${{\phi }^{\prime }}_{ysoll}=0$$

Furthermore, when the first control element 920 is actuated, a target position of the load can be determined, which is used as an additional target specification for the control. As a rule, the position of the load L corresponds to the position x of the trolley (ie, the suspension point AUP) and the current angle of rotation θ of the boom. These details are then stored as target specifications x _store , θ _store stored and, in addition to the target values θ' _target = 0, x' _target = 0, and I' _target = 0 (no control for crane operation), assumed for sway damping, and the state control is carried out accordingly. The following applies to the target values in the above control specification: $$x_{soll}=x_{store}$$

$$x{\text{'}}_{soll}=0$$

$${\phi }_{xsoll}=0$$

$$\phi {\text{'}}_{xsoll}=0$$

$${\theta }_{soll}={\theta }_{store}$$

$$\theta {\text{'}}_{soll}=0$$

$${\phi }_{ysoll}=0$$

$${{\phi }^{\prime }}_{ysoll}=0$$

5 shows a corresponding flow chart to illustrate this sway damping function.

In step S1, a check is made to determine whether the sway control function is activated during inactive crane operation. If this is the case (alternative: Yes), the process continues with step S2. Otherwise (alternative: No), the process continues with step S1.

In step S2, the position x, θ of the trolley LK (i.e., the suspension point AUP) is temporarily stored as x _store , θ _store and adopted as the target value for the subsequent control.

In step S3, the state control is carried out, whereby the target values x _soll = x _store , θ _soll = θ _store , I _soll are assumed in addition to the target values θ' _soll =0, x' _soll =0 and I' _soll =0 for sway damping and the state control is carried out accordingly.

In step S4, a check is made to determine whether the sway control function has ended and a follow-up time has elapsed. If this is the case (alternative: Yes), the process is terminated; otherwise (alternative: No), the system returns to step S3 and continues the state control.

A disturbance compensation function can be provided using a functional extension that can be activated or deactivated by a second control element 930. The disturbance compensation function can, for example, take into account external influences on the load system, such as wind pressure or vibrations of the subsurface, and maintain the current position of the load L despite the presence of (persistent) disturbances. If the function is activated by actuating the second control element 930, it remains active until it is terminated by corresponding actuation of the second control element 930. The disturbance compensation function remains active only as long as the crane is not actively operated, i.e., the load is not moved by external commands.

In 6 A flow chart is shown to illustrate the disturbance compensation function.

In step S11, a check is made to determine whether the disturbance compensation function is activated during inactive crane operation. If this is the case (alternative: Yes), the process continues with step S12. Otherwise (alternative: No), the process continues with step S11.

$$P_{ysoll}=\theta +arctan\frac{sin\left({\phi }_y\right)\cdot l}{x}$$

In step S12, the current absolute load position p _xsoll , p _ysoll is stored as the target value. The current absolute load position p _xsoll , p _ysoll to be stored can be calculated as $$P_{xsoll}=x+sin\left({\phi }_x\right)\cdot l$$

$$P_{ysoll}=\theta +arctan\frac{sin\left({\phi }_y\right)\cdot l}{x}$$

In step S13, the state control is activated, with varying target values for the trolley position x _target and the rotation angle θ _{target being} specified to the state control according to the control cycles. The pendulum length I _target remains unchanged.

$${\theta }_{soll}=p_{ysoll}-arctan\frac{sin\left({\phi }_y\right)\cdot l}{x}$$

To maintain the absolute position p _xsoll , p _ysoll of the load, the following applies: $$x_{soll}=p_{xsoll}-sin\left({\phi }_x\right)\cdot l$$

$${\theta }_{soll}=p_{ysoll}-arctan\frac{sin\left({\phi }_y\right)\cdot l}{x}$$

These values are determined continuously, ie recalculated for each control cycle, since the pendulum angles φ _x , φ _y and pendulum angular velocities φ' _x , φ' _y can change continuously with varying disturbance influences.

$${x^{\prime }}_{soll}=0$$

$${\phi }_{xsoll}=unbestimmt$$

$${{\phi }^{\prime }}_{xsoll}=unbestimmt$$

$${\theta }_{soll}=p_{ysoll}-arctan\frac{sin\left({\phi }_y\right)\cdot l}{x}$$

$${{\theta }^{\prime }}_{soll}=0$$

$${\phi }_{ysoll}=unbestimmt$$

$${{\phi }^{\prime }}_{ysoll}=unbestimmt$$

wobei x_soll, θ_soll entsprechend den Regelungszyklen wie oben beschrieben stetig aktualisiert werden. Somit kann auf sich ändernde Störeinflüsse entsprechend reagiert werden und die absolute Position der Last bleibt unverändert.The target values of the state variables are then during the active disturbance compensation function $$x_{soll}=p_{xsoll}-sin\left({\phi }_x\right)\cdot l$$

$${x^{\prime }}_{soll}=0$$

$${\phi }_{xsoll}=unbestimmt$$

$${{\phi }^{\prime }}_{xsoll}=unbestimmt$$

$${\theta }_{soll}=p_{ysoll}-arctan\frac{sin\left({\phi }_y\right)\cdot l}{x}$$

$${{\theta }^{\prime }}_{soll}=0$$

$${\phi }_{ysoll}=unbestimmt$$

$${{\phi }^{\prime }}_{ysoll}=unbestimmt$$

where x _soll , θ _soll is continuously updated according to the control cycles described above. This allows for appropriate response to changing disturbances, while the absolute position of the load remains unchanged.

The state variables φ _x , φ' _x , φ _y , φ' _y marked as indeterminate are not taken into account in the control by setting the corresponding control deviation or the associated element (factor) of the control vector K to zero during the activated disturbance compensation function.

In step S14, a check is made to determine whether the disturbance compensation function has been completed. If this is the case (alternative: Yes), the process is terminated; otherwise (alternative: No), the system returns to step S13 and continues the state control.

The disturbance compensation function can be deactivated by actuating the second control element 930 or by joystick operation to initiate load transport.

By actuating a third control element 940 (e.g., in the form of a pushbutton switch), a positioning function can be activated. The positioning function remains active as long as the third control element 940 is actuated and is active during a predetermined follow-up time, for example, between 5 and 30 seconds, preferably between 5 and 15 seconds, for example, 10 seconds. The positioning function provides for moving the load by manually pushing and pulling in the settling area, thus directing it with high precision to the correct desired load position.

In 7 A flow chart is shown to illustrate the positioning function.

In step S21, a check is made to determine whether the positioning function is activated during inactive crane operation. If this is the case (alternative: Yes), the process continues with step S22. Otherwise (alternative: No), the process continues with step S21.

$$x{\text{'}}_{soll}=unbestimmt$$

$${\phi }_{xsoll}=0$$

$$\phi {\text{'}}_{xsoll}=0$$

$${\theta }_{soll}=unbestimmt$$

$$\theta {\text{'}}_{soll}=unbestimmt$$

$${\phi }_{ysoll}=0$$

$$\phi {\text{'}}_{ysoll}=0$$

In step S22, the state controller is activated, but the target values of the positions x, θ and speed x', θ' of the trolley LK and the slewing gear DW are not taken into account, whereby the target values are assumed as follows: $$x_{soll}=unbestimmt$$

$$x{\text{'}}_{soll}=unbestimmt$$

$${\phi }_{xsoll}=0$$

$$\phi {\text{'}}_{xsoll}=0$$

$${\theta }_{soll}=unbestimmt$$

$$\theta {\text{'}}_{soll}=unbestimmt$$

$${\phi }_{ysoll}=0$$

$$\phi {\text{'}}_{ysoll}=0$$

The state variables x _soll , x' _soll , θ _soll , θ' _soll marked as indeterminate are not taken into account in the control by setting the corresponding control deviation or the associated element (factor) of the control vector K to zero while the disturbance compensation function is activated.

In step S23, a check is made to determine whether the positioning function has been completed. If this is the case (alternative: Yes), the process is terminated; otherwise (alternative: No), the system returns to step S22 and continues the state control.

The third control element 940 must be continuously actuated during positioning to prevent uncontrolled movements of the load L. The non-zero oscillation angle φ _x , φ _y resulting from pulling the load L or the load handling device UF forces the state control to compensate for the pulling direction, so that the load is moved in the corresponding direction according to the pulling force. As soon as the pulling force is removed, the trolley LK positions itself precisely over the load L, thus fixing the new load position.

Furthermore, a load lifting function can be implemented that is permanently active or can be activated using a fourth control element 950, ensuring additional safety when lifting the load. If the trolley LK, i.e., the suspension point AUP of the hoist rope, is not positioned exactly perpendicular to the center of gravity, an immediate pendulum oscillation can occur when lifting the load, which depends on the lateral offset of the suspension point AUP from the center of gravity. This is almost always the case in practice, since the crane operator is generally unable to position the load handling device UF precisely above the load center of gravity.

By using the state control described above, the suspension point AUP can be positioned exactly above the center of gravity when tightening the load handling device UF before the load L is lifted.

The load lifting function is described in the flow chart of the 8 explained in more detail.

In step S31, the hoist HW is activated to lift the load according to the instructions of the crane operator, e.g. using a fourth control element 950.

In step S32, a check is made to determine whether the load lifting function is activated. If so (alternative: Yes), the process continues with step S33. Otherwise (alternative: No), the process terminates with a jump to step S36.

In step S33, the lifting force is monitored using the mass sensor device 620. If the lifting force exceeds a predetermined threshold lifting force value, which can be determined by the weight forces of the load-handling device UF, the hoist rope HSL, and the load rope LSL, it can be assumed that the hoist rope HSL is taut and the measured pendulum angle φ _x, φ _y indicates the offset of the center of mass from the suspension point AUP on the trolley LK. In this case (alternative: yes), the method continues with step S34; otherwise (alternative: no), the method returns to step S33 and continues to wait for the threshold lifting force value to be reached.

$$x{\text{'}}_{soll}=unbestimmt$$

$${\phi }_{xsoll}=unbestimmt$$

$$\phi {\text{'}}_{xsoll}=0$$

$${\theta }_{soll}=unbestimmt$$

$$\theta {\text{'}}_{soll}=unbestimmt$$

$${\phi }_{ysoll}=0$$

$$\phi {\text{'}}_{ysoll}=0$$

Now, in step S54, the state control is started by specifying the following as target specifications: $$x_{soll}=unbestimmt$$

$$x{\text{'}}_{soll}=unbestimmt$$

$${\phi }_{xsoll}=unbestimmt$$

$$\phi {\text{'}}_{xsoll}=0$$

$${\theta }_{soll}=unbestimmt$$

$$\theta {\text{'}}_{soll}=unbestimmt$$

$${\phi }_{ysoll}=0$$

$$\phi {\text{'}}_{ysoll}=0$$

The state variables marked as indeterminate are ignored in the control by setting the corresponding control deviation or the associated element (factor) of the control vector K to zero while the disturbance compensation function is activated.

In step S35, a check is made as to whether the target specification of the pendulum angle φ _xsoll = 0, φ _ysoll = 0 and the pendulum angular velocity φ' _xsoll = 0, φ' _ysoll = 0 has been achieved, i.e. all corresponding control deviations are below a predetermined threshold value of, for example, less than 0.3° of the corresponding pendulum angle. This threshold value can generally be dependent on the hoist rope length, e.g. 0.1°, for hoist rope lengths of more than 20m, and 0.2 - 0.3° for hoist rope lengths I ₁ of less than 20m. If this is the case (alternative: yes), the method continues with step S36. Otherwise, the state control of step S34 continues.

Before the lifting force is further increased beyond the point at which the load is actually lifted, the state control is further executed. This enables the precise positioning of the trolley LK over the load center of gravity, so that the load can be lifted vertically, i.e., without initial pendulum oscillation.

The load is then lifted in step S36.

Furthermore, a position approach function can be implemented using a fifth control element 960. The position approach function serves to move to a stored position when approaching it, and to stop the load L there without oscillation. Only after stopping at the stored position is the position approach function deactivated again, and the load can be moved in any direction according to the crane operator's instructions.

der Last L oder der Laufkatze LK (d.h. des Aufhängungspunkts AUP) x, θ gespeichert werden (z.B. als x_store, θ_store).In step S41, a check is made to determine whether a position approach function has been activated. If this is the case (alternative: Yes), e.g., upon actuation of the fifth control element 960, a current absolute position p _x = x + sin(φ _x ) · l, $p_y=\theta +arctan\frac{sin\left({\phi }_y\right)\cdot l}{x}$

of the load L or the trolley LK (i.e. the suspension point AUP) x, θ are stored (e.g. as x _store , θ _store ).

If an absolute load position is stored according to the position approach function, the crane can be operated in the conventional manner in step S43.

$${x^{\prime }}_{soll}=0$$

$${\phi }_{xsoll}=0$$

$${{\phi }^{\prime }}_{xsoll}=0$$

$${\theta }_{soll}=p_y;$$

$${{\theta }^{\prime }}_{soll}=0$$

$${\phi }_{ysoll}=0$$

$${{\phi }^{\prime }}_{ysoll}=0$$

In step S44, a check is carried out to determine whether the current absolute position of the load L or the position of the suspension point AUP is approaching the stored position, which is determined by a continuously performed query. If this is determined (alternative: yes), in step S45 the stored position x _soll = p _x , θ _soll = p _y is used as the target position for the load, and the state controller is then executed accordingly. Further operation by the crane operator (or an automated crane control system) is irrelevant for the further target specification. After determining that the stored position is approaching, only the positions x, θ are specified as the target specification, so that the state controller operates purely as a position controller. The target specifications then correspond to: $$x_{soll}=p_x;$$

$${x^{\prime }}_{soll}=0$$

$${\phi }_{xsoll}=0$$

$${{\phi }^{\prime }}_{xsoll}=0$$

$${\theta }_{soll}=p_y;$$

$${{\theta }^{\prime }}_{soll}=0$$

$${\phi }_{ysoll}=0$$

$${{\phi }^{\prime }}_{ysoll}=0$$

The state variables marked as indeterminate are not taken into account in the control by setting the corresponding control deviation or the associated element (factor) of the control vector K to zero during the activated position approach function.

If the stored position is determined to have been reached in step S46 (alternative: Yes), the state control is initially terminated in step S47. Otherwise (alternative: No), the method continues with step S45.

If the approached position is left again by activating the crane operation, the position approach function is activated again and the process continues with step S43.

It can be provided that the stored load position is forgotten by pressing the fifth control element 960 again.

QUOTES CONTAINED IN THE DESCRIPTION

This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 10 2009 032 270 A1 [0005]
• EP 1 628 902 B1 [0006]
• EP 1 652 810 B1 [0007]
• DE 10 2020 120 699 A1 [0030]

Cited non-patent literature

• J. Smoczek et al., “Robust Predictive Control of an Overhead Crane,” https://doi.org/10.5604/01.3001.0010.2940 [0008]
• Liebherr Electronics” of Liebherr Werk Nenzing GmbH from 09/2012 [0009]
• Holger Lutz, Wolfgang Wendt “Pocketbook of Control Engineering”, Europa-Lehrmittel, 2021, ISBN 9783808558706 [0041]
• Otto Föllinger, “Control Engineering”, Vde Verlag GmbH, 2022, ISBN 9783800755189 [0041]

Claims (12)

Device, in particular a control unit (100), for operating a jib crane (2) with the aid of a state control, wherein the state control effects a control of a movement of a suspended load (L) at least in one direction of movement and is based on a state vector, wherein the device is designed to: - detect state variables of the state vector, which includes information on a position and a speed (x', θ') of a movable suspension point (AUP) to which a load system comprising a hoist rope (HSL), a load suspension device (UF) arranged at a lower end of the hoist rope (HSL) and a load (L) suspended below the load suspension device (UF) is attached, and includes information on a load position (φ _x , φ _y ) and a load speed (φ' _x , φ' _y ) of a center of mass of the load system with respect to the suspension point (AUP), - determine at least one manipulated variable (u* _LK , u* _DW , u* _HW ) for moving the suspension point (AUP) in the at least one direction of movement based on the state control; - controlling the jib crane (2) depending on the at least one manipulated variable (u* _LK , u* _DW . u* _HW ). Device according to Claim 1 , wherein the device is designed with the state control in that when a crane state changes, in particular when a hoist rope length (I ₁ ) and/or a radial position of the suspension point (AUP), and in particular depending on a mass of the load system, a parameterization of a state space description is updated in the state space and by means of a method of pole specification or the LQ method, a linear combination of the control deviations of the state variables is determined, which is specified by a control vector (Kx, Ky), and is used to calculate the at least one manipulated variable (u* _LK , u* _DW , u* _HW ) for moving the suspension point (AUP). Device according to Claim 1 or 2 , wherein the at least one manipulated variable (u* _LK , u* _DW , u* _HW ) comprises an adjustment speed of a trolley (KW) of a tower crane or an adjustment speed of a luffing angle of a boom (KA) of a mobile slewing crane and/or an adjustment speed of a slewing gear (DW). Device according to one of the Claims 1 until 3 , wherein the device is designed to specify the load position (φ _x , φ _y ) as the relative position of the center of mass of the load system with respect to the suspension point as a function of a hoist cable angle, which indicates an angular deviation of the hoist cable attached to the suspension point (AUP) from the vertical through the suspension point (AUP), from a load cable angle, which indicates an angular deviation of a center of mass of the load (L) at a suspension point on the load suspension device (UF) from the vertical, and to determine the load position (φ _x , φ _y ), in particular further as a function of a hoist cable length (I ₁ ) between the suspension point (AUP) and a center of mass of the load suspension device (UF), and/or a load cable length (I ₂ ) between the suspension point (ANP) and the load center of gravity, and in particular to determine the load position (φ _x , φ _y ) as a pendulum angle φ _x , φ _y ) of the centre of mass with respect to the perpendicular through the suspension point (AUP) or as the vertical distance of the centre of mass from the perpendicular through the suspension point (AUP). Device according to one of the Claims 1 until 4 , wherein the device is designed to operate the state control in such a way that a sway damping function is realized when, in particular, the manual or automated crane operation specifies a speed of the suspension point (AUP) for at least one of the directions of movement or a first operating element (920) is actuated to activate the sway damping function, wherein for sway damping a target specification of the information on the load position φ _x , φ _y ) and the load speed (φ' _x , φ' _y ) of the center of mass of the load system is specified as zero, the target specification for the speed (x') of the suspension point (AUP) is specified as zero and the target specification for a position of the suspension point (AUP) is specified as a position determined depending on the specified speed of the suspension point (AUP). Device according to Claim 5 , wherein the device is designed to keep the pendulum oscillation damping active for a predetermined follow-up time when all target values are set to zero. Device according to one of the Claims 1 until 6 , wherein the device is designed to operate the state control in such a way that a disturbance compensation function is realized, wherein the state control is continuously supplied with a target specification for the position of the suspension point (AUP), which is determined as a function of a stored absolute position of the load, and a target specification of the Speed of the suspension point (AUP) is specified as zero and the load position (φ _x , φ _y ) and the load speed (φ' _x , φ' _y ) of the center of mass of the load system are disregarded, in particular by setting the corresponding control deviations of the load position φ _x , φ _y ) and the load speed (φ' _x, φ' _y ) of the center of mass of the load system to zero during the activated disturbance compensation function, wherein in particular the target specification of the information on the position of the suspension point (AUP) is determined based on the current load position (φ _x , φ _y ) of the center of mass, a pendulum length (I) of the load system and the current position of the suspension point (AUP). Device according to Claim 7 , wherein a second operating element (930) is provided to activate or deactivate the disturbance compensation function, and in particular to deactivate the disturbance compensation function during active crane operation for load transport, wherein in particular when the disturbance compensation function is activated the absolute position of the load (L) is stored. Device according to one of the Claims 1 until 8 , wherein the device is designed to operate the state control in such a way that a positioning function is carried out, wherein the state control is given the information on the load position (φ _x , φ _y ) and the load speed (φ' _x , φ' _y ) of the center of mass of the load system as zero as target specifications and the position (x, θ) and the speed (x', θ') of the suspension point (AUP) are not taken into account, in particular by setting the corresponding control deviations during the activated positioning function or the associated element (factor) of the control vector K to zero. Device according to one of the Claims 1 until 9 , wherein the device is designed to operate the state control such that a load lifting function is realized when a load (L) is to be lifted, wherein the information on the load position (φ _x , φ _y ) is determined when a lifting force on the hoist rope (HSL) exceeds a predetermined lifting force threshold value and the load (L) has not yet been lifted, wherein the state control is carried out with target specifications for the load position φ _x , φ _y ) and load speed (φ' _x, φ' _y ) and the speed (x', θ') of the suspension point (AUP) of zero, wherein the control deviation for the position (x, θ) of the suspension point (AUP) is not taken into account, in particular by setting the corresponding control deviations or the associated element (factor) of a/the control vector K to zero during the activated load lifting function. Device according to one of the Claims 1 until 10 , wherein the device is designed to operate the state control in such a way that a position approach function is implemented, in which a stored position is approached and the load (L) is brought to a standstill there, wherein a current position is stored in accordance with a user request, wherein the state control is carried out with a target specification for the position (x, θ) of the suspension point (AUP) which corresponds to the stored position, a target specification for the speed (x', θ') of the suspension point (AUP) of zero, a target specification for the load position φ _x , φ _y ) and the load speed (φ' _x, φ' _y ) of zero, as soon as the position of the suspension point (AUP) has approached the stored position of the suspension point (AUP) during ongoing crane operation, in particular below a predetermined threshold distance. Jib crane (2) comprising: - one or more drive devices for moving a suspension point for a load system; - the device according to one of the Claims 1 until 11 , wherein the device is designed to control the jib crane (2) by controlling the one or more drive devices (LW, DW).

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