Tower crane and control unit for operating a tower crane, trolley and trolley drive

Abstract

A tower crane (2) comprising: a tower (T) with a vertical axis (H); a cat-shaped extension (KA) projecting from the tower (T); a slewing mechanism (DW) for rotating at least the trolley boom (KA) around the vertical axis (H); a sensor device (510) for determining a rotation angle (θu) of the trolley boom (KA) about the vertical axis (H); a trolley (LK) movable along the trolley boom (KA) with at least one first and one second deflection pulley (202, 204) for a lifting rope (HSL); a load handling device (UF) with at least one deflection pulley (302) for the lifting rope (HSL); a sensor device (310) arranged on the load-handling device (UF) for determining at least one first deflection angle (φ_2x, φ_2y) of the load-handling device (UF) to the perpendicular passing through the load-handling device (UF); the lifting rope (HSL), which, starting from a lifting mechanism (HW), is guided at least over the first deflection pulley (202) of the trolley (LK), the at least one deflection pulley (302) of the load handling device (UF) and the second deflection pulley (204) of the trolley (LK), and which is attached to a distal section (4) of the trolley boom (KA); the lifting mechanism (HW); a sensor device (210) arranged on the trolley (LK) for determining at least one second deflection angle (φ_1y, φ_ux) of at least one section (HSL#1, HSL#2) of the lifting rope (HS) located between the trolley (LK) and the load handling device (UF) to the vertical passing through the trolley (LK), wherein at least one sensor signal generated by the sensor device (210) represents a distance between the sensor device (210) and at least one section (HSL#1, HSL#2) of the lifting rope (HSL); a trolley carriage (KW) which is connected to the trolley (LK) by means of a trolley cable (KSL) for its movement along the trolley boom (KA); a sensor device (410) for determining a rotation angle difference (Δθ) between the rotation angle (θu) of the trolley boom (KA) about the vertical axis (H) and the rotation angle (θ) of the trolley (LK) about the vertical axis (H); and a control unit (100) which operates the slewing mechanism (DW), the lifting mechanism (HW) and the trolley drive (KW) as a function of at least the rotation angle (θu), as a function of at least one first deflection angle (φ_2x, φ_2y), as a function of at least one second deflection angle (φ_1y, φ_ux) and as a function of the rotation angle difference (Δθ).

Description

[0001] The invention relates to a tower crane and a control unit for operating a tower crane, a trolley for a tower crane and a trolley undercarriage for a tower crane.

[0002] Advances in the field of tower cranes are described.

[0003] The problems of the prior art are solved by a tower crane according to claim 1, a control unit for operating a tower crane according to a subordinate claim, a trolley for a tower crane according to a further subordinate claim, and a trolley undercarriage for a tower crane according to another subordinate claim. Advantageous further developments can be found in the subclaims, the following description, and the drawings.

[0004] A first aspect of the description relates to a tower crane comprising: a tower with a vertical axis; a trolley jib projecting from the tower; a slewing gear for rotating at least the trolley jib about the vertical axis; a sensor device for determining a rotation angle of the trolley jib about the vertical axis; a trolley movable along the trolley jib and having at least a first and a second deflection pulley for a hoist rope; a load-handling device having at least one deflection pulley for the hoist rope; a sensor device arranged on the load-handling device for determining at least a first deflection angle of the load-handling device relative to the vertical line passing through the load-handling device; the hoist rope, which, starting from a hoisting gear, is guided at least over the first deflection pulley of the trolley, the at least one deflection pulley of the load-handling device, and the second deflection pulley of the trolley, and which is fastened to a distal portion of the trolley jib;the hoisting gear; a sensor device arranged on the trolley for determining at least one second deflection angle of at least one section of the hoisting rope located between the trolley and the load-handling device relative to the vertical line running through the trolley; a trolley undercarriage connected to the trolley by means of a trolley rope for its movement along the trolley boom; a sensor device for determining a rotation angle difference between the rotation angle of the trolley boom about the vertical axis and the rotation angle of the trolley about the vertical axis; and a control unit which operates the slewing gear, the hoisting gear, and the trolley undercarriage depending on at least the rotation angle, depending on the at least one first deflection angle, depending on the at least one second deflection angle, and depending on the rotation angle difference.

[0005] The tower crane provided, using the sensors provided, enables the precise and real-time determination of the load position during crane operation, thus reducing load sway. The proposed tower crane forms the basis for the merging, preparation, and computer processing of sensor data to determine a precise current situation. Estimates of important control variables such as angles are avoided through sensor data fusion, and any errors in individual sensor data are also compensated for. For sensor fusion, different data are collected on the trolley, the load handling device, and the boom using the sensor devices.

[0006] If the crane operator moves the load using a joystick, they no longer have to manually attempt to reduce the swaying motion that would otherwise occur. An assistance system can therefore be provided that advantageously allows the load to be moved at high speed without the crane operator having to worry about the load swaying. With the proposed crane, loads can be lowered more quickly, which has a beneficial effect on the time required for work processes on the construction site.

[0007] An advantageous example is characterized in that the sensor device for determining the rotation angle difference is arranged fixedly to the trolley boom, in particular on the trolley boom or on a frame of the trolley chassis.

[0008] The rigid connection to the trolley boom improves the measurement of the slewing angle difference. The connection to the trolley frame simplifies the assembly and installation of the tower crane.

[0009] An advantageous example is characterized in that a sensor signal generated by the sensor device for determining the rotation angle difference represents a distance between the sensor device and a section of the trolley rope, which is located between a deflection pulley fixed proximal to the trolley boom and the trolley; wherein the rotation angle difference is determined by means of the control unit as a function of the sensor signal representing the distance.

[0010] Depending on the position of the trolley along the trolley boom, bending of the trolley affects the rotational position of the trolley. The position of the section of the trolley rope represents the offset of the trolley relative to a rotation angle around the tower's vertical axis. This allows the concrete rotational position of the trolley relative to the vertical axis to be determined without the need for additional sensors.

[0011] An advantageous example is characterized in that the sensor device for determining the rotation angle difference is arranged starting from the tower in a first or proximal half, in particular in the first or proximal third, of the length of the trolley boom.

[0012] The deflection of the trolley boom plays a greater role the farther the trolley is from the tower. However, if the trolley is closer to the tower, the deflection of the trolley boom plays a less significant role. Therefore, the proposed arrangement of the sensor device in the first half or first third of the trolley is advantageous. This also enables integration with the trolley undercarriage.

[0013] An advantageous example is characterized in that a sensor signal generated by the sensor device for determining the at least one second deflection angle represents a distance between the sensor device and the at least one section of the hoist rope; and wherein the at least one second deflection angle is determined by means of the control unit as a function of the sensor signal representing the distance.

[0014] Advantageously, the distance measurement can be used to measure at least one second deflection angle in a simple manner.

[0015] An advantageous example is characterized in that the tower crane comprises: a further sensor device arranged on the trolley for determining at least one angle of inclination of the trolley to a horizontal; and wherein the control unit additionally operates the slewing gear, the hoist gear, and the trolley undercarriage depending on the at least one angle of inclination.

[0016] Due to the nonlinear bending of individual boom segments of the trolley boom, the inclination angle is difficult to derive using simple mathematical linearizations. The proposed sensor-based detection of the inclination angle improves the accuracy of the downstream control system.

[0017] A second aspect of the description relates to a method for operating a tower crane, comprising: determining at least one first pendulum angle, which characterizes a deflection of a virtual center of gravity of a multiple pendulum suspended from the trolley relative to a plumb line passing through the trolley in a first spatial plane; determining at least one second pendulum angle, which characterizes a deflection of the center of gravity of the multiple pendulum relative to the plumb line passing through the trolley in a second spatial plane; determining at least one angle of rotation of the trolley about the vertical axis of the tower; and determining at least one manipulated variable for operating the tower crane, in particular by means of at least one slewing gear, at least one hoist, and at least one trolley traveling gear, as a function of the at least one first pendulum angle, as a function of the at least one second pendulum angle, and as a function of the at least one angle of rotation.

[0018] By determining the pendulum angle and the rotation angle of the trolley, it is possible to determine the load position and to implement near-real-time control using a control model that represents the crane and the load movement.

[0019] The approach presented advantageously avoids the use and derivation of controlled variables. Instead, the actual load situation on the crane and below the crane boom is determined using the sway angle and the rotation angle of the trolley. Using sensor fusion, the influence of the double pendulum, which is typically found in crane operations, on the control of the load movement is reduced or eliminated.

[0020] The proposed method yields a simplified virtual single-pendulum system—regardless of the complexity of the mechanical design of the arrangement below the trolley—that can be operated with simpler control algorithms that, above all, do not require the determination of crane-specific torsional and bending moments. The proposed method can be advantageously applied to a wide variety of different tower crane configurations without the need for complex adaptations to the crane design.

[0021] Furthermore, the proposed method and system enables not only position-related control of the load, i.e. specifying a trajectory for the load, but also the simultaneous possibility of speed-related control of the load. This makes it comparable to the currently common speed-related crane control using PLCs and more accessible for the crane operators. With PLC control, the crane operators specify a speed for the respective drives using joystick commands. With speed-related control of the load, the crane operator would specify a speed of the load using a joystick command. This can therefore provide an assistance system for the crane operator. On the other hand, the proposed method and system enables fully automated travel. The system proposed here is therefore suitable for more intuitive manual as well as semi- or fully automated operation.fully automated control and provides the necessary basis for this.

[0022] An advantageous example comprises: determining a deflection angle, lying in the first plane, of at least one section of the hoisting rope located between the trolley and the load-handling device relative to the vertical line passing through the trolley; determining a deflection angle, lying in the first plane, of the load-handling device suspended from the trolley via the hoisting rope relative to the vertical line passing through the load-handling device; wherein the first pendulum angle is determined as a function of the deflection angle, lying in the first plane, of the at least one section of the hoisting rope and as a function of the deflection angle, lying in the first plane, of the load-handling device.

[0023] This sensor fusion improves the precise determination of the pendulum angle. Unwanted fluctuations in the sensor signals are reduced by sensor fusion.

[0024] An advantageous example comprises: determining a first weighting factor as a function of a pendulum length; wherein the first pendulum angle is determined by weighting the deflection angle of the section of the hoist rope lying in the first plane as a function of the first weighting factor and by weighting the deflection angle of the load-handling device lying in the first plane as a function of the first weighting factor.

[0025] The pendulum length is advantageously used to reduce vibrations caused by the design of the trolley and the load handling device with different pendulum lengths for the determination of the control variables.

[0026] An advantageous example comprises: determining an angle of inclination of the trolley to the horizontal; determining a compensated deflection angle in the first plane as a function of the angle of inclination of the trolley and as a function of the deflection angle of the at least one section of the hoist rope in the first plane; wherein the first pendulum angle is determined as a function of the compensated deflection angle of the at least one section of the hoist rope in the first plane and as a function of the deflection angle of the load-handling device in the first plane.

[0027] This sensor fusion precisely accounts for the deflection of the trolley boom, which varies depending on the position of the trolley, the load, and the design of the trolley boom.

[0028] An advantageous example comprises: determining a deflection angle, lying in the second plane, of the at least one section of the hoisting rope located between the trolley and the load-handling device relative to the vertical line passing through the trolley; determining a deflection angle, lying in the second plane, of the load-handling device suspended from the trolley via the hoisting rope relative to the vertical line passing through the load-handling device; and wherein the second deflection angle is determined as a function of the deflection angle lying in the second plane and as a function of the deflection angle of the load-handling device lying in the second plane.

[0029] This sensor fusion improves the precise determination of the pendulum angle. Unwanted fluctuations in the sensor signals are reduced by sensor fusion.

[0030] An advantageous example comprises: determining a second weighting factor as a function of the pendulum length; and wherein the second deflection angle is determined by weighting the deflection angle of the at least one section of the hoist rope lying in the second plane as a function of the second weighting factor and by weighting the deflection angle of the load-carrying means lying in the second plane as a function of the second weighting factor.

[0031] The pendulum length is advantageously used to reduce vibrations caused by the design of the trolley and the load handling device with different pendulum lengths for the determination of the control variables.

[0032] An advantageous example comprises: determining a length of one of the sections of the hoist rope between the trolley and the load-handling device; and determining the pendulum length as a function of the length of one of the sections of the hoist rope and a predetermined length of a load rope between the load-handling device and the load, which length can be specified manually during operation.

[0033] The specified length of the load rope compensates for the inaccuracy in determining the total length of the multiple pendulum. This reduces the overall error. As long as the overall error remains within approximately ±10% of the total length of the multiple pendulum, adequately damped control is ensured. This behavior of the load attached to the load-handling device by means of slings has been empirically proven through test experiments.

[0034] If the length of the hoist rope section is 40m and the length of the load rope is 5m, the total length is 45m. The controller can therefore easily tolerate an inaccuracy of ±4.5m. In the majority of cases, this leads to the desired control behavior. Exceeding this tolerance does result in a slight overshoot, but it is still smaller than would be the case without the proposed control.

[0035] An advantageous example comprises: determining a rotation angle of the trolley boom about the vertical axis; determining a rotation angle difference between the rotation angle of the trolley boom about the vertical axis and the rotation angle of the trolley about the vertical axis; and wherein the rotation angle of the trolley about the vertical axis of the tower is determined as a function of the rotation angle of the trolley boom and as a function of the rotation angle difference.

[0036] This sensor fusion improves the precise determination of the trolley’s rotation angle.

[0037] An advantageous example is characterized in that the determination of the at least one manipulated variable is activated when at least one of the following conditions occurs: presence of at least one target variable not equal to zero; presence of a manual activation of the determination of the at least one manipulated variable originating from an operating unit; and presence of a request for readjustment.

[0038] An advantageous example comprises: updating a model, in particular matrices characterizing the model, as a function of the pendulum length, a position of the trolley, and as a function of the mass associated with the multiple pendulum, determined in particular by means of a sensor device; and wherein the determination of the at least one manipulated variable is carried out as a function of the updated model.

[0039] Advantageously, the position of the trolley, the measured mass and the pendulum length allow the model to be updated.

[0040] An advantageous example comprises: updating a controller, in particular gain factors, as a function of the model, in particular of the matrices characterizing the model, and as a function of the pendulum length; and wherein the determination of the at least one manipulated variable is carried out as a function of the updated controller.

[0041] A third aspect of the description relates to a control unit for operating a tower crane, comprising: means for determining at least one first pendulum angle, which characterizes a deflection of a virtual center of gravity of a multiple pendulum suspended from a trolley relative to a plumb line passing through the trolley in a first spatial plane; means for determining at least one second pendulum angle, which characterizes a deflection of the center of gravity of the multiple pendulum relative to the plumb line passing through the trolley in a second spatial plane; means for determining at least one angle of rotation of the trolley about the vertical axis of the tower;and means for determining at least one manipulated variable for operating the tower crane, in particular by means of at least one slewing gear, at least one hoist and at least one trolley of the tower crane, as a function of the at least one first pendulum angle, as a function of the at least one second pendulum angle and as a function of the at least one rotation angle.;

[0042] A fourth aspect of the description relates to a trolley for a tower crane, comprising: a chassis for moving the trolley along a trolley boom; at least two deflection pulleys arranged fixedly relative to the chassis for deflecting a hoist rope in the direction of a load-handling device; and a sensor device arranged fixedly relative to the chassis for determining at least one deflection angle of a section of the hoist rope located between the trolley and a load-handling device relative to the vertical line passing through the trolley.

[0043] Determining at least one deflection angle of the hoist rope on the trolley makes it possible to determine the load situation precisely.

[0044] An advantageous example is characterized in that at least one sensor signal generated by the sensor device represents a distance between the sensor device and at least one section of the hoist rope.

[0045] By determining the distance, the deflection angle can be determined more precisely - especially compared to a camera measurement.

[0046] An advantageous example is characterized in that at least two sensors are assigned to the at least one section of the hoisting rope, which sensors are directed at the section of the hoisting rope from different angles.

[0047] By placing two sensors at a distance from each other, the measurement itself is improved and error handling in the event of inconsistent sensor signals is enabled.

[0048] An advantageous example is characterized in that the sensor device is arranged at least in part between the at least two sections of the hoist rope.

[0049] This provides a more compact sensor device. Furthermore, it is protected and located in a proximal area of ​​the trolley. Furthermore, individual sensors can be integrated into a single unit.

[0050] An advantageous example comprises: at least one further sensor device arranged fixedly to the chassis for generating at least one further sensor signal which characterizes an inclination of the trolley to a horizontal.

[0051] Advantageously, sensor fusion can improve the precise determination of the deflection angle in a plane spanned by the tower and trolley boom.

[0052] A fifth aspect of the description relates to a trolley undercarriage for arrangement on a trolley boom of a tower crane, comprising: a frame; a drive unit arranged fixedly to the frame for winding and unwinding a trolley rope; and a sensor device arranged fixedly to the frame for determining a rotation angle difference between a rotation angle of the trolley boom about a vertical axis of a tower of the tower crane and a rotation angle of the trolley about the vertical axis.

[0053] Advantageously, the sensor device for determining the angle of rotation difference is integrated into the trolley chassis. This eliminates the need to mount the sensor device separately on the trolley boom. Consequently, the crane design is simplified.

[0054] An advantageous example is characterized in that a sensor signal generated by the sensor device for determining the rotation angle difference represents a distance between the sensor device and a section of the trolley rope.

[0055] Depending on the position of the trolley along the trolley boom, bending of the trolley affects the rotational position of the trolley. The position of the section of the trolley rope represents the offset of the trolley relative to a rotation angle around the tower's vertical axis. This allows the concrete rotational position of the trolley relative to the vertical axis to be determined without the need for additional sensors.

[0056] The drawing shows: Fig. 1 a tower crane in schematic form; Fig. 2, Fig. 3, Fig. 16 and Fig. 19 each a pendulum system; Fig. 4 a feedback of sensor signals; Fig. 5 and Fig. 6 a determination of control variables; Fig. 7 and Fig. 10 each shows a trolley in schematic form; Fig. 8 and Fig. 11 each a determination of the position of a section of a hoist rope by means of a sensor device; Fig. 9 the trolley and various positions of a pulley of a load handling device; Fig. 12 the trolley and parts of a sensor device; Fig. 13 an angle of inclination of the trolley to a horizontal produced by bending the trolley boom; Fig. 14 a rotation angle difference between a rotation angle of the trolley and a rotation angle of the trolley boom caused by bending of the trolley boom; Fig. 15 and Fig. 17 each shows a signal flow diagram; Fig. 18 the tower crane in a top view; and Fig. 20 a control unit for operating the tower crane.

[0057] Fig. 1 shows a schematic side view of a tower crane 2 for lifting, moving and setting down a load L. 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 boom KA projecting from the tower T. The trolley boom KA is in the Fig. 1 not designed to be luffing. In an example not shown, the trolley boom KA can also be designed to be luffing, whereby the luffing trolley boom KA is moved by means of a luffing drive.

[0058] The tower crane 2 comprises a slewing gear DW, arranged for example on a counter jib GA, for rotating at least the trolley jib KA about the vertical axis H. The tower crane 2 comprises a sensor device 510, designed for example as a rotation angle sensor, for determining a rotation angle θ_u of the trolley jib KA about the vertical axis H in a yx plane.

[0059] 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 also be referred to 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.

[0060] A sensor device 310 arranged on the load-handling device UF, for example in the form of a gyroscope, is configured to determine a first deflection angle φ_2x, φ_2y of the load-handling device UF relative to the perpendicular passing through the load-handling device UF.

[0061] The hoist rope HSL is guided from a hoisting gear HW for winding and unwinding the hoist rope 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.

[0062] The hoisting gear HW comprises 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.

[0063] A sensor device 620 is according to Fig. 1 is coupled to the deflection pulley 22 and detects its deflection in the xy plane, which changes depending on the mass m of the suspended load L or the multiple pendulum below the trolley LK. The 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.

[0064] A sensor device 210 arranged on the trolley LK is configured to determine a second deflection angle φ_1y, φ_ux of a section HSL#1, HSL#2 of the hoist rope HS located between the trolley LK and the load-handling device UF, relative to the vertical line passing through the trolley LK. A sensor signal generated by the sensor device 210 to determine the second deflection angle φ_1y, φ_ux represents a distance between the sensor device 210 and the section HSL#1, HSL#2 of the hoist rope HSL. The second deflection angle φ_1y, φ_ux is determined by the control unit 100 as a function of the sensor signal of the sensor device 210 representing the distance.

[0065] 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 winch winds up one part of the trolley cable KSL and unwinds the other part, thus moving the trolley LK.

[0066] A sensor device 420, for example a rotation angle sensor that counts the revolutions, is arranged fixedly to the frame 402 and generates a sensor signal that characterizes the position x of the trolley LK.

[0067] A 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 the rotation angle of the trolley LK about the vertical axis H. The 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. A sensor signal generated by the sensor device 410 for determining the rotation angle difference Δθ represents a distance between the sensor device 410 and a section KSL#1 of the trolley rope KSL, which is located between a deflection pulley 6 proximal to the trolley boom KA and the trolley LK. A deflection pulley 8 arranged distal to the trolley boom KA deflects the trolley rope KSL from the trolley chassis KW to the trolley LK.The rotation angle difference Δθ is determined by the control unit 100 as a function of the sensor signal representing the distance. The sensor device 410 is arranged, starting from the tower T, in a first or proximal half, in particular in the first or proximal third, of the length of the trolley boom KA.

[0068] The arrangement of the sensor device 410 for determining a rotation angle difference Δθ is shown in Fig. 1, for reasons of clarity, is schematically shown parallel to the vertical axis z at a distance from the trolley cable KSL. In the embodiment explained in the previous paragraph, the sensor device 410 is arranged perpendicular to the plane of the drawing at a distance from the trolley part KSL. Of course, other embodiments of the sensor device 410 are also conceivable, for example, a sensor arranged as shown, which optically observes the deflection of the trolley cable KSL from vertically above or from vertically below, for example, and determines the signal representing the rotation angle difference Δθ.

[0069] The trolley KW comprises the frame 402 and a drive unit arranged fixedly relative to the frame 402 for winding and unwinding a trolley rope KSL. The sensor device 410 arranged fixedly relative to the frame 402 is configured to determine the rotation angle 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 rotation angle θ of the trolley LK about the vertical axis H. The sensor signal generated by the sensor device 410 for determining the rotation angle difference Δθ represents a distance between the sensor device 410 and a section KSL#1 of the trolley rope KSL.

[0070] A control unit 100 operates the slewing gear DW, the hoisting gear HW and the trolley KW depending on the angle of rotation θ_u, depending on the first deflection angle φ_2x, φ_2y, depending on the second deflection angle φ_1y, φ_ux and depending on the angle of rotation difference Δθ.

[0071] Another sensor device 220, arranged fixedly on the trolley LK, in particular in relation to its chassis, and designed, for example, as a gyroscope, serves to determine an inclination angle Δφ of the trolley LK relative to a horizontal plane. The sensor device 220 determines a sensor signal that characterizes an inclination of the trolley LK relative to a horizontal plane, in particular an inclination angle relative to a horizontal plane lying in an xh plane spanned by the vertical axis and the longitudinal axis of the trolley boom. The control unit 100 additionally operates the slewing gear DW, the hoisting gear HW, and the trolley undercarriage KW depending on the inclination angle Δφ.

[0072] The multiple pendulum suspended on the trolley LK is shown in the following Fig. 2 and Fig. 3 and comprises the two sections HSL#1, HSL#2 of the hoist rope HSL, the load handling device UF suspended from the hoist rope HSL, a load rope LSL arranged on the load handling device UF, and the load L arranged on the load rope LSL. The same applies to two-trolley operation, whereby the multiple reeving of the hoist rope provides the pendulum located below with three or more pulleys on the trolleys as boom-side reference points. In this context, a multiple or double pendulum is understood to mean the arrangement located below the trolley or below the trolley's pulleys.

[0073] A length l_1 is determined using a sensor 610, for example, a rotation angle sensor that counts revolutions, which is assigned to 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 can be determined.

[0074] A length l_k of the load rope LSL between the load-handling device UF and the load L can be specified, for example, via an operating unit 900. The operating unit 900 is, for example, a control panel or a radio remote control. Target values ​​S_soll are implicitly transmitted to the control unit 100 via a joystick of the operating unit 900.

[0075] Fig. 2 shows a schematic diagram of the tower crane from the Fig. 1 existing double pendulum. This double pendulum, which consists of all components located below the trolley LK, results in two angles φ1, φ2 of the ropes to the respective vertical and two lengths l1, l2 of the ropes.

[0076] While l1 and the angle φ1 are relatively easy to measure, the length l2 between the load handling device UF and the load L, as well as the mass m of the load and the center of gravity S of the load's mass, remain constantly variable during operation. The angle φ1 is also not trivial to measure as a measurable quantity. And even if the length l2 were estimated, a significant control inaccuracy would result, which would continue to cause the system to oscillate when the drives are actively controlled.

[0077] Fig. Figure 3 shows the simplification of the multiple pendulum proposed in this description to prevent or reduce pendulum motion. The multiple pendulum from Fig. 2 is considered a single pendulum. One parameter is the angle of deflection of the load relative to the trolley. This cannot be measured with simple sensors such as cameras, ultrasonic sensors, or laser-based distance measurement systems, since an actual pendulum angle φ is not found in reality on any of the objects physically encountered in crane operation. This pendulum angle φ is approximately determined based on sensor measurements. The control system described below is based, among other things, on the consideration of the following parameters: φ angle of oscillation between the straight line pointing to the virtual center of gravity S of the load and the plumb line L#LK in the center of the trolley LK; l Distance between the trolley and the virtual center of gravity S of the virtual load L; S Virtual center of gravity of the virtual load L; and m mass of the virtual load L.

[0078] Fig. 4 shows in reference to Fig. 1 the determination of manipulated variables or actuating speeds u by a determination unit 110. The respective actuating speed is specified, for example, as a percentage of the maximum speed for the respective drive. At least the sensor data and setpoint variables S'_soll are fed to the determination unit 110 in order to determine the drive speeds u. A determination unit 120 determines the setpoint variables S'_soll as a function of the setpoint variables S_soll originating from the control unit 900, whereby the individual setpoint variables S_soll are multiplied by a gain factor.

[0079] Furthermore, it is possible to send an ACT signal to the detection unit 110 via the control unit 900, which activates the detection unit and the implemented control system. For example, lifted loads can be moved manually, with the control unit 100 controlling the tower crane in such a way that it prevents the load from swinging during manual movement.

[0080] Fig. 5 shows an embodiment of the detection unit 110 from Fig. 4. Means 1002 are configured to determine a first pendulum angle φ_x, which characterizes a deflection of the virtual center of gravity of the multiple pendulum suspended from the trolley relative to a plumb line passing through the trolley in a first imaginary spatial plane xh, which is spanned by the vertical axis of the tower of the tower crane. Means 1004 are configured to determine a second pendulum angle φ_y, which characterizes a deflection of the center of gravity of the multiple pendulum relative to the plumb line passing through the trolley in a second imaginary spatial plane, which is a plumb line of the first spatial plane xh and runs parallel to the vertical axis H. Means 1006 determine the angle of rotation θ of the trolley about the vertical axis of the tower as a function of the angle of rotation θ_u of the trolley boom and as a function of the angle of rotation difference Δθ.

[0081] Further means 1010 serve to determine the manipulated variable u for operating the tower crane, in particular the slewing gear, the hoist and the trolley, as a function of the first pendulum angle φ_x, as a function of the second pendulum angle φ_y and as a function of the angle of rotation θ.

[0082] Means 1024 are configured to determine the pendulum length l as a function of the length l_1 of the sections of the hoist rope and the predefined and, in particular, manually predeterminable length l_k of the load rope between the load-handling device and the load during operation.

[0083] Means 1012 are configured to determine a first weighting factor kx as a function of the pendulum length l, wherein the first pendulum angle φ_x is determined by weighting the deflection angle φ_ux of the section HSL#1, HSL#2 of the hoist rope HSL in the first plane as a function of the first weighting factor kx and by weighting the deflection angle φ_2x of the load handling device UF in the first plane as a function of the first weighting factor kx.

[0084] Means 1014 are configured to determine a compensated deflection angle φ_1x lying in the first plane xh as a function of the inclination angle Δφ of the trolley and as a function of the deflection angle φ_ux of the section of the hoist rope lying in the first plane, wherein the means 1002 are configured to determine the first pendulum angle φ_x by weighting the compensated deflection angle φ_ux lying in the first plane as a function of the first weighting factor kx and by weighting the deflection angle φ_2x of the load handling device lying in the first plane as a function of the first weighting factor.

[0085] Means 1022 are configured to determine a second weighting factor ky as a function of the pendulum length l, wherein the means 1004 are configured to determine the second deflection angle φ_y by weighting the deflection angle φ_1y of the section of the hoist rope lying in the second plane yh as a function of the second weighting factor ky and by weighting the deflection angle φ_2y of the load handling device UF lying in the second plane yh as a function of the second weighting factor ky.

[0086] Means 1030 are configured to update a model, in particular matrices A, B characterizing the model, as a function of the pendulum length l, the position x of the trolley, and as a function of the mass m associated with the multiple pendulum. Means 1032 serve to update a controller, wherein a matrix of gain factors K' is determined as a function of the model, in particular matrices A, B characterizing the model, and as a function of the pendulum length l. The determination of the manipulated variables u_LK, u_DW, u_HW is carried out as a function of the updated controller.

[0087] According to a respective block 1040, 1042, 1044, 1046, and 1048, a respective derivative x', l', θ', φ_x', φ_y' of the respectively supplied quantity is determined. Alternatively, the quantity x' can also be supplied directly.

[0088] The means 1010 determines the manipulated variables u as a function of the matrix K', the desired variables S'_soll, the pendulum length l', the pendulum angles, the angle of rotation of the trolley, and as a function of the derivatives x', l', θ', φ_x', φ_y'.

[0089] Fig. Figure 6 shows another example of the investigation unit 110. In contrast to Fig. 5, the determination unit 110 comprises an observer 130, to which the determined set drive speeds u and measurement signals Z are fed. The observer determines the state vector Z~. A state controller 132 and an addition point 134 determine the drive speeds u to be set as a function of the state vector Z~ and the setpoint variables S_soll. For example, a transposed gain vector K' is generated using the pole placement method: K'=[K(1)K(2)K(3)]

[0090] A state vector for the trolley, where x' corresponds to the actual speed of the LK, is given by Z→˜=[x' φx φ'x]

[0091] The control speed u_LK is then, for example, as follows: uLK=xset'∗K(1)−Z→˜∗K'=xset'∗K(1)−(x'∗K(1)+(x'∗K(1)+φx∗K(2)+φx'∗K(3))= =xset'∗K(1)−x'∗K(1)−φx∗K(2)−φx'∗K(3)=(xset'−x')∗K(1)−φx∗K(2)−φx'∗K(3) =−1∗[(x'−xset')φx φx']∗K'

[0092] In other words, actual-setpoint differences are formed in the state vector, Phi_soll and Phi_dot_soll are equal to zero, and then multiplied by the gain vector K', which results in the scalar control speed. The unit of

[0093] Fig. Figure 7 shows a schematically illustrated example of a structure of the trolley LK. A chassis 206 is provided for moving the trolley LK along a travel axis 207 of the trolley boom. For example, the chassis 206 comprises a plurality of wheels 212a-d, which are mounted for movement on rails of the trolley boom. At least two deflection pulleys 202, 204, which are arranged fixedly relative to the chassis 206, are configured to deflect the hoist rope toward a load-handling device UF.

[0094] The sensor device 210, which is fixed relative to the chassis 206, is configured to determine the deflection angles φ_1y, φ_ux of the sections HSL#1, HSL#2 of the hoist rope located between the trolley LK and a load-handling device relative to the vertical line passing through the trolley LK. A sensor signal generated by the sensor device 210 represents a distance between the sensor device 210 or parts thereof and the respective section HSL#1, HSL#2 of the hoist rope located between the deflection pulleys 202, 204 of the trolley LK and the deflection pulley or pulleys of the load-handling device.

[0095] Two or more sensors 214#1, 216#1; 214#2, 216#2 are assigned to the respective section HSL#1, HSL#2 of the hoist rope, which are directed from different angles onto the section HSL#1, HSL#2 of the hoist rope HSL.

[0096] In an example not shown, the sensor device 210 is arranged at least in part between the two sections HSL#1, HSL#2 of the hoist rope.

[0097] To detect the rope angle φ_1, sensors 214#1, 216#1, 214#2, and 216#2 are arranged on the trolley LK. These sensors can be ultrasonic sensors, LiDAR sensors, or other sensors, for example, to measure the distance between the respective sensor 214#1, 216#1, 214#2, and 216#2 and the associated section HSL#1, HSL#2. In the example shown, sensors 214#1, 216#1; 214#2, and 216#2 are aligned in pairs perpendicular to each other in the respective X or Y axis direction on the sections HSL#1, HSL#2. Thus, the rope deflection is measured relative to the position of the sensor.

[0098] Since sensors 214 and 216 are aligned on the same or parallel axis, all non-parallel cable deflections can be calculated out. The deflections of the cables relative to each other are thus compensated for by measurement. These include, for example, the different configurations of a trapezoidal arrangement of the two sections HSL#1, HSL#2 between the trolley LK and the load handling device that occur during lifting and lowering operations. This effect can be calculated out by determining the cable length between the trolley and the load handling device.

[0099] Fig. Figure 8 schematically shows the calculation of the distance of the sensors to the section HSL#1 of the hoist rope using the example of the two sensors 214#1, 216#1. The sensors 214#1, 216#1 assigned to the respective rope section HSL#1 are aligned in pairs such that a resulting distance C_1 is at a 45° angle to the crane's coordinate system.

[0100] Using the measured values ​​U1 and U2, which represent a respective distance of the rope section HSL#1 to the respective sensor 214#1, 216#1, the following equations can be derived: U12=X102+Y102 U22=X102+(C1−X10)2

[0101] Equations (1) and (2) for Y 10 2 and X 10 2 resolved result in: X102=U12−Y102 Y102=U22−(C1−X10)2

[0102] By inserting equation (4) into equation (3) we get X 10 as follows: Y102=U12−(U22−(C1−X10)2) X102=U12−U22+(C1−X10)(C1−X10) X102=U12−U22+(C12−2⋅C1⋅X10+X102) X102=U12−U22+C12−2⋅C1⋅X10+X102 0=U12−U22+C12−2⋅C1⋅X10 −U12+U22−C12=−2⋅C1⋅X10 X10=U12−U22+C122⋅C1

[0103] Now, equation (5) is inserted into equation (4). This gives Y 10 to: Y10=U22−(C1−U12−U22+C122⋅C1)2

[0104] Now ΔX1 and ΔY1 can be calculated using trigonometric functions and the result from equation (6): α=arcsin(|Y10|U1)−45° ΔX1U1=sin(α) ΔX1=U1⋅sin(arcsin(|Y10|U1)−45°) α=arcsin(|Y10|U1)−45° ΔY1U2=sin(α) ΔY1=U2⋅sin(arcsin(|Y10|U2)−45°)

[0105] Analogous to equations (7) and (8), ΔX2 and ΔY2 are determined for the opposite side, ie the other sensor pair.

[0106] Fig. Figure 9 illustrates how the movement of the load handling device in the h-direction results in an additional deflection ΔX1 or ΔX2 of the hoist rope HSL in the x-direction, depending on the position of the load handling device relative to the deflection pulleys 202, 204 of the trolley LK. Although this movement is calculated out by measurement, depending on the configuration, it may be that the rope runs out of the detection range of the sensors once the load handling device is a certain distance away from the deflection pulleys 202, 204. In particular, when using the load handling device with only one deflection pulley 302, the rope angle changes significantly. This would move the hoist rope HSL out of the measuring range of the sensors 214#1 and 214#2, which are located in Fig. 7. To extend the scanning range in the x-direction to compensate for the deflection of the rope caused by the lifting and lowering of the load-carrying device, sensors 214, 216 can be mounted on Fig. 7 arranged in pairs in a V shape.

[0107] Fig. Figure 10 shows the aforementioned V-shaped arrangement of the sensors 214#1 and 216#1 or 214#2 and 216#2 of the sensor device of the trolley LK. The remaining features of the trolley LK are Fig. 1 and Fig. 7. The V-shaped arrangement results in a larger measuring range 218#1, 218#2 in the x-direction, while the measuring range in the y-direction does not change significantly.

[0108] In the example shown, the sections HSL#1 and HSL#2 of the hoist rope are located between the sensors 214, 216. In an alternative example not shown, the sensors 214, 216 are located at least partially, in particular entirely, between the sections HSL#1 and HSL#2 of the hoist rope.

[0109] Fig. 11 illustrates the calculation rules for determining the position of the respective section HSL#1 or HSL#2 of the hoist rope HSL using the example of the arrangement of the Fig. 10.

[0110] The angles are calculated according to equations (9) and (10): U12=X102+Y102 U22=X102+(C1−Y10)2

[0111] Equations (9) and (10) for Y 10 2 and X 10 2 resolved results in: Y102=U12−X102 X102=U22−(C1−Y10)2

[0112] By inserting equation (11) into equation (12) we get Y 10 to: Y102=U12−(U22−(C1−Y10)2) Y102=U12−U22−(C1−Y10)2 Y102=U12−U22+C12−2⋅C1⋅Y10+Y102 0=U12−U22+C12−2⋅C1⋅Y10

[0113] To Y 10 solved this gives: Y10=U12−U22+C122⋅C1

[0114] The calculated size Y 10 is inserted into equation (12) to calculate X 10 to calculate: X10=U22−(C1−Y10)2 ΔY1=C12−Y10

[0115] To calculate ΔX1, the height H of the associated isosceles triangle will be calculated. H2=a2+(C12)2 H=a2+(C12)2

[0116] For ΔX1 we get: ΔX1=X10−H=X10−a2+(C12)2

[0117] Analogous to equations (14) and (17), ΔX2 and ΔY2 are calculated for the opposite section of the hoist rope.

[0118] Fig. Figure 12 illustrates that the unwinding behavior of the hoist rope over the deflection pulleys 202, 204 results in different lengths L1 and L2 of the sections HSL#1, HSL#2 of the hoist rope up to a sensor axis 222. This is compensated for by equation (18). The average rope length L thus remains constant. L=L1+L22

[0119] The distances ΔX1 and ΔY1 or ΔX2 and ΔY2 determined by means of equations (7) and (8) or (14) and (17) are now converted into angles using the known and constant rope length from (18) up to the deflection pulley 202, 204.

[0120] The uncompensated angle φ ux According to equation (19), the deflection of the load relative to the trolley in the x-direction is described. Due to the inclination of the trolley LK, a deviation from the absolute angle of the sections HSL#1, HSL#2 of the hoist rope relative to the vertical through the trolley LK occurs. The resulting uncompensated angle φ ux is therefore compensated. φux=arctan(ΔX1L)+arctan(ΔX2L)2

[0121] Analogously, the angle φ 1y according to equation (20). This describes analogously to the angle φ ux the deflection of the load in the y-direction. However, compensation is not necessary here. φ1y=arctan(ΔY1L)+arctan(ΔY2L)2

[0122] Fig. 13 illustrates the compensation of the angle φ ux , for which the trolley's angle of inclination is used. The angle of inclination Δφ resulting from the bending of the trolley boom KA during load movements is determined by sensors on the trolley LK. This angle of inclination Δφ records the absolute angle of the trolley LK to the horizon in the imaginary hx-plane spanned by tower T and the trolley boom KA. The angle of inclination Δφ is calculated between a perpendicular L_LK through the center of the trolley and an axis A_LK that is perpendicular to the current travel axis of the trolley LK.

[0123] With the determined angle of inclination Δφ, the angle φ ux to φ 1x be compensated: φ1x=φux−Δφ

[0124] Thus, the two deflection angles or rope angles φ 1x and φ 1y captured using equations (20) and (21).

[0125] The signals from the different sensor devices 210 and 310 Fig. 1 measured deflection angles are multiplied by the factors k x : (0≤k x ≤1) and k y : (0≤k y≤1). The aforementioned factors weight the influence of the respective angle on the result of the sensor fusion. The respective factor is adjusted depending on the pendulum length l in order to minimize unwanted oscillations of the sensor data in extreme ranges. For long rope lengths (>50m), the sensor data of the sensor device on the trolley are overlaid by the natural oscillation of the rope sections of the hoist rope. In contrast, for short rope lengths (<10m), the sensor data of the sensor device on the load handling device are overlaid by the natural oscillation due to the pronounced rocking of the bottom block - especially when the hook is empty. Accordingly, the pendulum angles, which correspond to a virtual rope angle up to the virtual load (see Fig. 2 and Fig. 3, determined according to equations (22) and (23): φx=kxφ1x+(1−kx)φ2x φy=kyφ1y+(1−ky)φ2y

[0126] The pendulum length l results from the definable length l k to: l=l1+lK

[0127] The fusion of the individual sensor data carried out in equations (22) and (23) reduces or eliminates unwanted phase-shifted oscillations.

[0128] The vibrations caused by the load-handling device are recorded on the trolley and the load-handling device with a phase shift and are advantageously eliminated by the addition in equations (22) (23). This is important because it often happens that the two end points of the double pendulum (in this case, the trolley and the load) are stationary, and only the middle part of the double oscillator (in this case, the bottom block or the load-handling device) still oscillates.

[0129] The pendulum angles φ now recorded are x and φ yare included in the described control system as controlled variables. The virtual length or pendulum length l is added to the crane model as a parameter. In other words, the load position determined by the aforementioned parameters is introduced into the control system as a control parameter.

[0130] By measuring the deflection of the section KSL#1 of the trolley rope, which is connected to the trolley, relative to the longitudinal axis A_KA of the trolley boom KA, the angle of rotation θ of the trolley LK around the vertical axis H of the tower T in the xy plane is determined.

[0131] In Fig. 14 shows how the elastic movement of the trolley boom KA results in a difference between the angle of rotation θ of the trolley LK and thus the load to the longitudinal axis A_KA of the trolley boom KA compared to the angle of rotation θ u of the tower T to the trolley boom KA.

[0132] The sensor device 410 for determining a rotation angle difference Δθ comprises according to Fig. 14 shows the two sensors 412a and 412b, which are arranged fixedly relative to the trolley boom in the imaginary xy plane, and between which the section KSL#1 of the trolley cable is located. The sensors 412a and 412b determine the respective distance to the section KSL#1 of the trolley cable. The rotation angle difference Δθ can be determined from the known distance between the sensor device 410 and the vertical axis of the tower. The sensors 412a and 412b are designed, for example, as ultrasonic sensors, LiDAR sensors, or other sensors for measuring the distance between the sensors 412a, 412b and the section KSL#1 of the trolley cable.

[0133] Alternatively, it is conceivable to measure the rotation angle difference Δθ using additional sensors such as an electronic compass, GPS or other geometric measuring methods, etc.

[0134] Consequently, the angle of rotation θ of the trolley LK and thus of the load to the longitudinal axis A_KA of the trolley boom KA is: θ=θu+Δθ

[0135] To the previously in Fig. The control system shown in Figure 4a will be discussed in general terms below using a state-space representation. In the state-space representation, n-order linear systems are decomposed into n first-order subsystems in order to simplify the mathematical description and design of the state controller. The trolley, for example, is a multi-variable system with four state variables, as it has just as many essential storage functions. Two of these state variables relate to the trolley and two to the multiple pendulum, which includes the hoist rope, load handling device, slings, and load. Both systems considered individually represent a doubly integrating system. They are coupled to one another, as a movement of the trolley always results in a movement of the multiple pendulum.The reaction of the movements of the multiple pendulum will be neglected here, since the frequency converter controls the speed of the trolley and thus prevents the reaction on the trolley.

[0136] The controller design is based on a mathematical description obtained through system analysis of the multivariable system. The differential equations are converted into matrix and vector form and can be transformed using matrix operations. This yields the system's eigenvalues, which, in this case, indicate the system's instability. With the pole specification method, a desired system is created based on newly selected eigenvalues ​​that exhibits stable behavior and the desired dynamics. The difference between the real, unstable system and the desired system is then applied by the state controller using the calculated controller coefficients.

[0137] The task of the state controller is to calculate the manipulated variable from the state variables and the setpoint. The state variables are multiplied by constant controller factors, and the setpoint is multiplied by the prefilter value. The sum of these products is then the desired manipulated variable. In simple terms, this could be described as four superimposed P controllers. This immediately shows that the state controller has no I or D components. The latter are only present insofar as one state variable can be the differential of another. Thus, D components are also incorporated into the control process.

[0138] Fig. Figure 15 shows a signal flow diagram relating to the trolley and resulting from the following equation (29). The trolley's speed u_LK corresponds to a variable at the controller output and reacts to a step change in the manipulated variable with a PT1 response. First, the linearized fourth-order process model is described. The four state variables are defined as follows: x LK position x' = v LK speed σ x Pendulum angle φ x ' Pendulum angular velocity: φ x ' can be obtained either with an observer or by numerical derivation: φxk'=(φxk−φxk−1)Ta T a Sampling time.

[0139] The following process values ​​are required to simulate the process and design the state controller: T StellTime constant of the PT1 element controlling the actuator (frequency converter + geared motor + inertia); l Pendulum length as distance to the load center S.

[0140] As already mentioned, the speed transition function can be approximated by that of a PT1 element. Thus, the speed transition function of the trolley is: x'=ULK⋅K⋅(1−e−tT)

[0141] K and T are parameters of the PT1 element and are determined below. The derivative of equation (26) yields the LK acceleration: x''=uLK⋅KT⋅e−tT

[0142] The equation (27) is etT and insert into (26), which gives: T⋅x''+x'=K⋅uLK x''=KT⋅uLK−1T⋅x'

[0143] Based on the Fig. 16 the motion sequence of the pendulum system is examined. The hanging multiple pendulum (see Fig. 2 and Fig. 3 of the previous description) two forces act: The downward force of gravity F g and the rope force F s The latter transfers the movements of the trolley LK to the load with mass m at the virtual center of gravity of the multiple pendulum. This results in balances of horizontal and vertical forces, the sum of which, according to Newton's equilibrium, is zero. New auxiliary variables are: x_Load horizontal position of the virtual center of gravity of the load or the multiple pendulum; and h_Load vertical position of the virtual center of gravity of the load or the multiple pendulum

[0144] The horizontal and vertical forces are given by equations (30) and (31): m⋅x_Last''+Fs⋅sin(φx)=0 −m⋅g+m⋅h_Last''+Fs⋅cos(φx)=0

[0145] For the equations of state in which only x, x', φ x and φ x' are included, all other variables (F s , x_Load and h_Load) are eliminated. If equation (30) is extended with cos(φ x ) and (31) with sin(φ x ), we get: m⋅x_Last''⋅cos(φx)+Fs⋅sin(φx)⋅cos(φx)=0 −m⋅g⋅sin(φx)+m⋅h_Last''⋅sin(φx)+Fs⋅cos(φx)⋅sin(φx)=0

[0146] If (32) is subtracted from (33), the bar force F s removed. The result is then divided by the load mass m, which is also removed: x_Last''⋅cos(φx)−h_Last''⋅sin(φx)=−g⋅sin(φx)

[0147] The coordinates of the load (x_load and h_load) are eliminated using the transformation equations: x_Last=x+l⋅sin(φx) h_Last=l⋅cos(φx)

[0148] Since the variables x_Last and h_Last appear in their second derivative in (34), they must be derived twice: x_Last'=x'+l⋅φx'⋅cos(φx) h_Last'=−l⋅φx'⋅sin(φx) h_Last''=x''+l⋅φx''⋅cos(ϕ)−l⋅φx'2⋅sin(φx) h_Last=−l⋅φx''⋅sin(ϕ)−l⋅φx'2⋅cos(φx)

[0149] The equations for x_Load" and h_Load" (38) are inserted into (39). This yields the nonlinear differential equation of the pendulum system: x''⋅cos(φx)+l⋅φx''=−g⋅sin(φx)

[0150] To linearize this differential equation, the pendulum angle φ x assumed to be very small: φx<<1⇒sin(φx)≈φx and cos(φx)≈1 and φx'2≈0 x''+l⋅φx''=−g⋅φx

[0151] The linearized differential equation (40) is solved for φ x '' (41) and is shown as a signal flow diagram in Fig. 17 shown. φx''=gl⋅φx−1l⋅x''

[0152] For x'' in the time equation for the pendulum system according to equation (41), the time equation (29) for the trolley can be used. This allows the connection of the signal flow diagrams shown above. Inserting equation (29) into (41) results in: φx''=−gl⋅φx−KT⋅l⋅x_Last+1T⋅l⋅x'

[0153] To describe the system in state space, the linear differential equations are converted into equations of state. For this purpose, the variables x, x', φ x and φ x ' replaced by the state variables q = [q0,q1,q2,q3]: x''=KT⋅uLK−1T⋅x' φx''=−gl⋅φx−KT⋅l⋅uLK+1T⋅l⋅x'

[0154] For a more concise short form, vectors and matrices are introduced. This yields the vector differential equation for state variables: [x'x''φx'φx'']=[01000−1T00000101l⋅T−gl0]⋅[xx'φxφx']+[0KT0−Kl⋅T]⋅uLK

[0155] The controller receives as setpoint the desired speed of the trolley in the range from -100 to 100% of nominal speed with an accuracy of ΔV=100%20000=0.005%=8.3mms and controls the speed of the trolley without amplification, from which K = K stg = 1. The actual speed follows the setpoint with a delay time of T = T stg = 0.2 s.

[0156] To enable oscillation-free positioning, a state controller is used to convert the undamped real system into a sufficiently damped desired system. To do this, numbers are first inserted into the input and system matrix: T = T stg = 0.2 s; K = K stg = 1; l: variable. ALK=[01000−500000105l−9.81l0]BLK=[050−5l]

[0157] In assistance control, the speed of the LK is the controlled variable. The controller ensures that the LK follows the speed setting as smoothly as possible. In this case, the position of the trolley is irrelevant; the state-space representation can be reduced to this state variable. The new matrix representation is: ALK=[−5000015l−9.81l0]BLK=[50−5l]

[0158] In order to design a controller, a rope length corresponding to the pendulum length l is assumed: e.g. for l = 5 m the following matrix representation results: ALK=[−5000011−1.9620]BLK=[50−1]

[0159] The system-describing eigenvalues ​​are obtained by determining the zeros of the characteristic polynomial: det(Λ⋅I−A)=0

[0160] Alternatively, you can use a simulation tool: eig(A)=[1.4007i−1.4007i−2.5]

[0161] The first and second imaginary solutions show that the real system is an undamped oscillating system, since the real part of the first 2 poles is 0.

[0162] For digital control, a discrete representation is required, which can be obtained, for example, in Matlab with the following command: [Ad,Bd,Cd,Dd]=c2d(A,B,C,D.Ta);

[0163] For T a = 0.1s: Ad=[0.7788000.00230.99020.09970.0441−0.19560.9902]Bd=[ 0.2212−0.0023−0.0441]

[0164] The eigenvalues ​​for discrete representation are: EWd=eig(Ad)=[0.9902+0.1396i0.9902−0.1396i 0.7788] abs(EWd)=[ 1 10.7788]

[0165] The first and second complex poles lie on the unit circle, which also indicates an oscillating system. In order to arrive at the desired pendulum-free system, the latter is defined by specifying its eigenvalues. The poles of the system are therefore specified (pole specification). The poles are positioned so that the available acceleration moment is not exceeded. The closer the poles are selected to the center of the unit circle, the more dynamic the desired system becomes and the greater the maximum deflection angle during the acceleration phase, which has a negative effect on the steel structure. An optimum is therefore determined in the sense of a compromise, taking both aspects into account. Should the cable length or pendulum length l change, the eigenvalues ​​and the resulting controller are recalculated or updated.

[0166] As an alternative to pole specification, a Riccati controller (LQ controller) can also be used. This is a state controller for a linear dynamic system whose feedback matrix is ​​determined by minimizing a quadratic cost function. This enables optimal controller design for specified state weights Q.

[0167] Based on the Fig. 18 and Fig. 19, a system analysis of the slewing gear is performed. The four state variables of the slewing gear are defined as follows: θ DW angle θ' DW angular velocity φ y Pendulum angle φ y ' Pendulum angular velocity, which is obtained either by observation or by numerical derivation.

[0168] The rotational movement of the trolley boom KA can be described by the following equation: IA⋅θ''=M−MR, using the following sizes: I Amoment of inertia acting on the rotating mechanism; M drive torque of the slewing gear; M R counter-moment; MR=FR⋅x MR=m⋅yL''⋅x FR=sin(φy)⋅m⋅g IA⋅θ''=M−sin(φy)⋅m⋅g⋅x

[0169] The equations of motion for the load are: m⋅yL''=y−m⋅g m⋅zL''=FR

[0170] The equation of motion for the load in the Y direction is: yL=y+l⋅sin(φy) yL'=y'+l⋅cos(φy)⋅φy' yL''=y''−l⋅sin(φy)⋅φy'2+l⋅cos(φy)⋅φy''

[0171] The equations of motion for the load in Z-direction are: zL=l−l⋅cos(φy) zL'=l⋅sin(φy)⋅φy' zL''=l⋅cos(φy)⋅φy'2+l⋅sin(φy)⋅φ''

[0172] Equations (55) and (56) together give IA⋅θ''=M−m⋅x⋅yL''

[0173] Inserting equation (58) into (60) gives: IA⋅θ''=M−m⋅x⋅(y''−l⋅sin(φy)⋅φy'2+l⋅cos(φy)⋅φy'') IAm⋅x⋅θ''=Mm⋅x−y''+l⋅sin(φy)⋅φy'2−l⋅cos(φy)⋅φy''

[0174] To obtain the first differential equation, the conversions from y'' to θ'' are carried out: y≈x⋅θ y'≈x⋅θ' y''≈x⋅θ''

[0175] Inserting the angle of rotation θ in radians into y'' gives: IAm⋅x⋅θ''=Mm⋅x−x⋅θ''+l⋅sin(φy)⋅φy'2−l⋅cos(φy)⋅γy'' IAm⋅x⋅θ''+x⋅θ''=Mm⋅x+l⋅sin(φy)⋅φy'2−l⋅cos(φy)⋅φy'' (IAm⋅x+s)⋅θ''=Mm⋅x+l⋅sin(φy)⋅φy'2−l⋅cos(φy)⋅φy''

[0176] The differential equation (64) is identical to the differential equation (39) from the modeling of the trolley: x''⋅cos(φx)+l⋅φx''=−g⋅sin(φx) l⋅φx''=−x''⋅cos(φx)−g⋅sin(φx)

[0177] Adapted to the rotating mechanism, this results in: φx→φy x''→y''=x⋅θ''

[0178] The second differential equation gives: l⋅φy''=−x⋅θ''⋅cos(φy)−g⋅sin(φy)

[0179] To linearize the differential equations, the pendulum angle φ y assumed to be very small: φx<<1⇒sin(φx)≈φx and cos(φx)≈1 and φx'2≈0

[0180] The control variable corresponds to the drive torque of the slewing gear drive: M=uDW θ''=m⋅x⋅gIA⋅φy+1IA⋅uDW φy''=−(m⋅x2⋅gl⋅IA+gl)⋅φy−xl⋅IA⋅uDW

[0181] In state space representation we get: [ θ' θ'' φy' φy'']=[01 000m⋅x⋅gIA 0000 010−(m⋅x2⋅gl⋅IA+gl)−gl0]⋅[ θ θ' φy φy']+[ 0 1IA 0−xl⋅IA]⋅uDW ADW=[01000m⋅x⋅gIA0000010−(m⋅x2⋅gl⋅IA+gl)−gl0] BDW=[ 0 1IA 0−xl⋅IA]

[0182] The controller design for the slewing gear (Y-direction) and the hoist follows essentially the same principle. The result is a crane model in state space consisting of three states for the trolley model, four states for the slewing gear model, and two states for the hoist model: Conditions: Z→=[x' φx φx' θ θ' φy φy' l l']; [x''φx'φx''θ'θ''φy'φy''l'l'']=[ALKADW→ALK00000000000000000 000ADW00000000000000000000AHW]⋅[x'φxφx'θ'θ'φyφy'l'l']+[BLK 0 0 0 0 0 00000BDW 0 0 0 00000BHW]⋅[ uLKuDWuHW]

[0183] For example, the controller uses the current position of the load relative to the horizontal tower axes or the speed of the load as a control variable.

[0184] The respective target values xsoll',θsoll,lsoll or Ssoll are integrated from the joystick inputs of the control unit. The speed u LK , and DW, u HWof the respective drive (trolley, slewing gear, and hoist) is used as a target to achieve both the target speed of the load or the target position of the load. The joystick target can be set either step-based or as a percentage of the maximum speed. The following equations refer to the examples of Fig. 5 and Fig. 6. Ssoll→=[xsoll' θsoll lsoll] u→=[uLK uDW uHW] Z→=[x φx θ φy l l']; Z→˜=[x' φx φx'˜ θ θ' φy φy'˜ l l'];

[0185] In the control loop, the future movements of the measured variables x' φ x θ θ' φ y l is calculated. On this basis, the controlled variable for the subsequent control loop is determined and specified to the crane as the target value.

[0186] In contrast to a conventional control system, which only allows damping of the vibration, an optimal trajectory of the movement of the load (neutralizing any upswing leading to swaying motion) is calculated based on the available (fused) sensor and model data, so that no strong swaying motion caused by the crane operator or the crane operation can occur.

[0187] Subsequent damping of the oscillating pendulum system is therefore not necessary, or the scope of control based on this is very limited and can be implemented effectively.

[0188] After activating control by specifying a setpoint, the controller enters the acceleration phase, during which not only the oscillation caused by the initial movement but also the initial oscillation is eliminated. This is followed, as long as the setpoint (step) remains constant, by the constant speed phase, where the load is moved at a constant speed without oscillation. Each setpoint or step change, in turn, initiates an acceleration or deceleration phase.

[0189] The control is also activated after pulsed operation of the control panel. In this case, only the initial pendulum movement is corrected. The correction time can be usefully limited to one pendulum period. As is well known, the pendulum period is only length-dependent and is calculated using the following formula: T=2⋅π⋅lg

[0190] Fig. Figure 20 shows a schematic diagram of the control unit 100. This consists of a first processing unit 150 and a second processing unit 160. The first processing unit 150 is connected to the crane's drives and provides safety functions such as emergency shutdowns and the like. For example, the processing unit 150 is designed as a programmable logic controller (PLC).

[0191] The second processing unit 160 is communicatively coupled to the first processing unit 150. In step 162, the second processing unit 160 waits for a message from the first processing unit. S_1, i.e., waits for a control telegram from the PLC. The first processing unit 150 periodically sends messages with current control commands and sensor data to the second processing unit 160. If the message includes target values, which are specified by the first processing unit 150, for example, via the joystick input from the control panel or the radio remote control, then starting from a step 164, the process proceeds to block 110. Fig. 1 and the control is performed. Step 166 checks whether manual activation of the control has been requested. If this is the case, block 110 is activated.

[0192] In a step 168, a check is made to determine whether readjustment is necessary. If, for example, no message is received from the first processing unit, a check is made to determine whether actual variables or variables derived therefrom exceed a predefined threshold value. If this is the case, block 110 is activated. The request for readjustment is determined, for example, if the angle of rotation θ of the trolley LK, the first oscillation angle, or the second oscillation angle exceeds a respective assigned threshold value. Readjustment is therefore carried out if the movement of the load has not yet been completed following the absence of a control command. To prevent the load from swaying, a follow-up movement of the load is initiated.

[0193] Block 110 determines manipulated variables, which are transferred to the first processing unit in a step 170 for forwarding to the crane drives. The determination of the manipulated variables u_LK, u_DW, u_HW via block 110 is thus activated when at least one of the following conditions occurs: Presence 164 of the target variable S'_soll being unequal to zero; Presence 166 of a manual activation of the determination 110 of the manipulated variable originating from an operating unit 900; and Presence 168 of a request for readjustment.

Claims

[1] A tower crane (2) comprising: a tower (T) with a vertical axis (H); a trolley boom (KA) projecting from the tower (T); a slewing gear (DW) for rotating at least the trolley boom (KA) around the vertical axis (H); a sensor device (510) for determining an angle of rotation (θu) of the trolley boom (KA) about the vertical axis (H); a trolley (LK) movable along the trolley boom (KA) with at least one first and one second deflection pulley (202, 204) for a hoist rope (HSL); a load-handling device (UF) with at least one deflection pulley (302) for the hoist rope (HSL); a sensor device (310) arranged on the load-handling means (UF) for determining at least a first deflection angle (φ_2x, φ_2y) of the load-handling means (UF) relative to the plumb line passing through the load-handling means (UF); the hoist rope (HSL), which, starting from a hoist (HW), is guided at least over the first deflection pulley (202) of the trolley (LK), the at least one deflection pulley (302) of the load-handling means (UF) and the second deflection pulley (204) of the trolley (LK), and which is fastened to a distal section (4) of the trolley boom (KA); the lifting gear (HW); a sensor device (210) arranged on the trolley (LK) for determining at least one second deflection angle (φ_1y, φ_ux) of at least one section (HSL#1, HSL#2) of the hoist rope (HS) located between the trolley (LK) and the load-carrying means (UF) to the vertical line running through the trolley (LK), wherein at least one sensor signal generated by the sensor device (210) represents a distance between the sensor device (210) and at least one section (HSL#1, HSL#2) of the hoist rope (HSL); a trolley (KW) which is connected to the trolley (LK) by means of a trolley rope (KSL) for its movement along the trolley boom (KA); a sensor device (410) for determining a rotation angle difference (Δθ) between the rotation angle (θu) of the trolley boom (KA) about the vertical axis (H) and the rotation angle (θ) of the trolley (LK) about the vertical axis (H); and a control unit (100) which operates the slewing gear (DW), the hoisting gear (HW) and the trolley (KW) as a function of at least the angle of rotation (θu), as a function of the at least one first deflection angle (φ_2x, φ_2y), as a function of the at least one second deflection angle (φ_1y, φ_ux) and as a function of the angle of rotation difference (Δθ). [2] The tower crane (2) according to claim 1, wherein the 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). [3] The tower crane (2) according to claim 1 or 2, wherein a sensor signal generated by the sensor device (410) for determining the rotation angle difference (Δθ) represents a distance between the sensor device (410) and a section (KSL#1) of the trolley rope (KSL), which is located between a deflection pulley (6) fixed proximal to the trolley boom (KA) and the trolley (LK); wherein the rotation angle difference (Δθ) is determined by means of the control unit (100) as a function of the sensor signal representing the distance. [4] The tower crane (2) according to one of the preceding claims, wherein the sensor device (410) for determining the rotation angle difference (Δθ) starting from the tower (T) is arranged in a first or proximal half, in particular in the first or proximal third, of the length of the trolley boom (KA). [5] The tower crane (2) according to one of the preceding claims, wherein the at least one second deflection angle (φ_1y, φ_ux) is determined by means of the control unit (100) as a function of the sensor signal representing the distance. [6] The tower crane (2) according to one of the preceding claims comprising: a further sensor device (220) arranged on the trolley (LK) for determining at least one angle of inclination (Δφ) of the trolley (LK) to a horizontal; and wherein the control unit (100) additionally operates the slewing gear (DW), the lifting gear (HW) and the trolley (KW) in dependence on the at least one inclination angle (Δφ). [7] A control unit (100) for operating a tower crane (2) comprising: Means (1002) for determining at least a first pendulum angle (φ_x), which characterizes a deflection of a virtual center of gravity of a multiple pendulum suspended from a trolley (LK) relative to a perpendicular passing through the trolley (LK) in a first spatial plane (xh); Means (1004) for determining at least one second pendulum angle (φ_y) which characterizes a deflection of the center of gravity of the multiple pendulum relative to the perpendicular passing through the trolley (LK) in a second spatial plane (yh); Means (1006) for determining at least one angle of rotation (θ) of the trolley (LK) about the vertical axis (H) of the tower (T); and Means (110; 1010) for determining at least one manipulated variable (u_LK, u_DW, u_HW) for operating the tower crane (2), in particular by means of at least one slewing gear (DW), at least one hoist (Hw) and at least one trolley (KW) of the tower crane (2), as a function of the at least one first oscillation angle (φ_x), as a function of the at least one second oscillation angle (φ_y) and as a function of the at least one rotation angle (θ). [8] A trolley (LK) for a tower crane (2) comprising: a chassis (206) for moving the trolley (LK) along a trolley boom (KA); at least two deflection pulleys (202, 204) arranged fixedly relative to the chassis (206) for deflecting a hoist rope (HSL) in the direction of a load-carrying means (UF); and a sensor device (210) arranged fixedly to the chassis (206) for determining at least one deflection angle (φ_1y, φ_ux) of a section (HSL#1, HSL#2) of the hoist rope (HSL) located between the trolley (LK) and a load-carrying means (UF) relative to the vertical line running through the trolley (LK), . wherein at least one sensor signal generated by the sensor device (210) represents a distance between the sensor device (210) and at least one section (HSL#1, HSL#2) of the hoist rope (HSL). [9] The trolley (LK) according to claim 8, wherein at least two sensors (214#1, 216#1; 214#2, 216#2) are assigned to the at least one section (HSL#1, HSL#2) of the hoist rope (HSL), which sensors are directed from different angles onto the section (HSL#1, HSL#2) of the hoist rope (HSL). [10] The trolley (LK) according to one of claims 8 to 9, wherein the sensor device (210) is arranged at least in part between the at least two sections (HSL#1, HSL#2) of the hoist rope (HSL). [11] The trolley (LK) according to one of claims 8 to 10 comprising: at least one further sensor device (220) arranged fixedly relative to the chassis (206) for generating at least one further sensor signal which characterizes an inclination of the trolley (LK) to a horizontal. [12] A trolley (KW) for mounting on a trolley boom (KA) of a tower crane (2) comprising: a frame (402); a drive unit arranged fixedly to the frame (402) for winding and unwinding a trolley rope (KSL); and a sensor device (410) arranged fixedly to the frame (402) for determining a rotation angle difference (Δθ) between a rotation angle (θu) of the trolley boom (KA) about a vertical axis (H) of a tower (T) of the tower crane (2) and a rotation angle of the trolley (LK) about the vertical axis (H). [13] The trolley (KW) according to the preceding claim, wherein a sensor signal generated by the sensor device (410) for determining the rotation angle difference (Δθ) represents a distance between the sensor device (410) and a section (KSL#1) of the trolley cable (KSL).

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