Tower crane, method and control unit for operating a tower crane, trolley and cat undercarriage

Abstract

A trolley (LK) for a tower crane (2) is provided, comprising: a chassis (206) for moving the trolley (LK) along a trolley jib (KA); at least two deflection pulleys (202, 204) fixed to the chassis (206) for deflecting a hoist rope (HSL) towards a load handling device (UF); and a sensor device (210) fixed 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 handling device (UF) relative to the vertical passing through the trolley (LK).

Description

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

[0002] Progress in the field of tower cranes is described.

[0003] The problems of the prior art are solved by a tower crane according to claim 1, by a method and a control unit for operating a tower crane according to dependent claims, a trolley for a tower crane according to a further dependent claim, and a trolley drive for a tower crane according to another dependent claim. Advantageous embodiments are found in the dependent claims, the following description, and the drawing.

[0004] A first aspect of the description concerns a tower crane, which comprises: a tower with a vertical axis; a trolley jib projecting from the tower; a slewing mechanism 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 with at least one first and one second pulley for a hoist rope; a load-handling device with at least one pulley for the hoist rope; a sensor device arranged on the load-handling device for determining at least one first deflection angle of the load-handling device relative to the vertical passing through the load-handling device; the hoist rope, which, starting from a hoisting mechanism, is guided at least over the first pulley of the trolley, the at least one pulley of the load-handling device, and the second pulley of the trolley, and which is attached to a distal section of the trolley jib;the hoist; a sensor device arranged on the trolley for determining at least one second deflection angle of at least one section of the hoist rope located between the trolley and the load-handling device relative to the vertical passing through the trolley; a trolley travel mechanism which is 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 mechanism, the hoist, and the trolley travel mechanism as a function of at least the rotation angle, as a function of the at least one first deflection angle, as a function of the at least one second deflection angle, and as a function of the rotation angle difference.

[0005] The provided tower crane, with its integrated sensors, enables precise, real-time determination of the load position during crane operation, thus reducing load oscillation. The proposed tower crane forms the basis for the merging, processing, and computational analysis of sensor data to generate a precise, real-time positional analysis. Estimating critical parameters such as angles is avoided through sensor data fusion, and any errors in individual sensor data are compensated for. For sensor fusion, various data points are acquired using sensors located on the trolley, the load-handling device, and the boom.

[0006] If the crane operator moves the load using a joystick, they no longer need to manually try to reduce the swaying motions 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 pay attention to any swaying. With the proposed crane, loads can thus be lowered more quickly, which has a positive impact on work processes on the construction site.

[0007] An advantageous example is characterized in that the sensor device for determining the difference in the angle of rotation is arranged in a fixed position relative 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 slew angle difference. Connecting it to the trolley chassis 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 angle of rotation represents a distance between the sensor device and a section of the trolley rope located between a deflection pulley fixed proximal to the trolley boom and the trolley; wherein the angle of rotation difference is determined by the control unit as a function of the sensor signal representing the distance.

[0010] Depending on the trolley's position along the trolley arm, any bending of the trolley arm affects its rotational position. The position of the trolley cable section represents an offset of the trolley relative to a rotational angle about the tower's vertical axis. Therefore, the trolley's precise rotational position relative to the vertical axis can be determined without additional sensors.

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

[0012] The bending of the trolley boom plays a greater role the further the trolley is from the tower. Conversely, if the trolley is closer to the tower, the bending of the trolley boom is less significant. Therefore, the proposed arrangement of the sensor device in the first half or third of the trolley is advantageous. This also allows for integration with the trolley drive.

[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 lifting cable; 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 allows for the simple measurement of at least one second deflection angle.

[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 mechanism, the hoisting mechanism and the trolley travel mechanism depending on the at least one angle of inclination.

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

[0017] A second aspect of the description concerns 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 perpendicular 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 perpendicular passing through the trolley in a second spatial plane; determining at least one rotation angle of the trolley about the vertical axis of the tower; and determining at least one control variable for operating the tower crane, in particular by means of at least one slewing mechanism, at least one hoisting mechanism, and at least one trolley drive, 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.

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

[0019] The presented approach advantageously avoids the use and derivation of controlled variables. Instead, the actual load situation at the crane and below the crane boom is determined via the pendulum angles and the trolley's rotation angle. Sensor fusion reduces or eliminates the influence of the double pendulum, typically encountered in crane operations, on the control of load movement.

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

[0021] Furthermore, the proposed method / system, in addition to position-based load control (i.e., specifying a trajectory for the load), also enables simultaneous speed-based load control. This makes it comparable to the currently common speed-based crane control using a PLC and more accessible to crane operators. With PLC control, crane operators specify a speed for the respective drives via joystick commands. With speed-based load control, the crane operator would specify the load speed via joystick command. This provides an assistance system for the crane operator. On the other hand, the proposed method / system also enables fully automated operation. Therefore, the system proposed here is suitable for both more intuitive manual and semi-automated / autonomous operation.Fully automated control can be used and provides the necessary basis for this.

[0022] An advantageous example comprises: determining a deflection angle in the first plane of at least one section of the hoist rope located between the trolley and the load-handling device with respect to the perpendicular passing through the trolley; determining a deflection angle in the first plane of the load-handling device suspended from the trolley via the hoist rope with respect to the perpendicular passing through the load-handling device; wherein the first pendulum angle is determined as a function of the deflection angle in the first plane of the at least one section of the hoist rope and as a function of the deflection angle 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 through sensor fusion.

[0024] An advantageous example includes: 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 lifting rope lying in the first plane as a function of the first weighting factor and by weighting the deflection angle of the load-bearing 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-bearing device when pendulum lengths differ, thus enabling the determination of the control variables.

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

[0027] This sensor fusion precisely accounts for the bending 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 in the second plane of the at least one section of the hoist rope located between the trolley and the load-handling device with respect to the perpendicular passing through the trolley; determining a deflection angle in the second plane of the load-handling device suspended from the trolley via the hoist rope with respect to the perpendicular passing through the load-handling device; and wherein the second deflection angle is determined as a function of the deflection angle in the second plane and as a function of the deflection angle in the second plane of the load-handling device.

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

[0030] An advantageous example includes: 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 lifting rope lying in the second plane as a function of the second weighting factor and by weighting the deflection angle of the load-bearing device 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-bearing device when pendulum lengths differ, thus enabling the determination of the control variables.

[0032] An advantageous example includes: determining the 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 can be specified manually, in particular during operation.

[0033] The predetermined length of the load rope compensates for inaccuracies in determining the total length of the multiple pendulum. This reduces the overall error. As long as the total error remains within approximately ±10% of the total length of the multiple pendulum, sufficiently damped control is ensured. This behavior of the load attached to the load-bearing device via slings has been empirically verified through test trials.

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

[0035] An advantageous example includes: 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 by the fact that the determination of at least one manipulated variable is activated when at least one of the following conditions occurs: The presence of at least one setpoint value other than zero; the presence of a manual activation of the determination of at least one manipulated variable originating from an operating unit; and the presence of a request for subsequent adjustment.

[0038] An advantageous example includes: updating a model, in particular matrices characterizing the model, depending on the pendulum length, a position of the trolley and depending on 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 depending on the updated model.

[0039] Advantageously, the position of the trolley, the measured mass and the pendulum length allow for an update of the model.

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

[0041] A third aspect of the description concerns a control unit for operating a tower crane, comprising: means for determining at least a first pendulum angle, which characterizes a deflection of a virtual center of gravity of a multiple pendulum suspended from a trolley relative to a perpendicular passing through the trolley in a first spatial plane; means for determining at least a second pendulum angle, which characterizes a deflection of the center of gravity of the multiple pendulum relative to the perpendicular passing through the trolley in a second spatial plane; means for determining at least one rotation angle of the trolley about the vertical axis of the tower;and means for determining at least one control variable for operating the tower crane, in particular by means of at least one slewing mechanism, at least one hoisting mechanism 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 concerns a trolley for a tower crane comprising: a chassis for moving the trolley along a trolley boom; at least two deflection pulleys fixed to the chassis for deflecting a hoist rope in the direction of a load-handling device; and a sensor device fixed 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 passing through the trolley.

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

[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 lifting rope.

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

[0046] An advantageous example is characterized by the fact that at least two sensors are assigned to at least one section of the lifting cable, which are directed at the section of the lifting cable from different angles.

[0047] Using two sensors spaced apart improves both the measurement itself and enables error handling in the case of inconsistent sensor signals.

[0048] An advantageous example is characterized in that the sensor device is arranged at least partially between the at least two sections of the lifting cable.

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

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

[0051] Sensor fusion can thus advantageously improve the precise determination of the deflection angle lying in a plane spanned by the tower and trolley boom.

[0052] A fifth aspect of the description concerns a trolley carriage for arrangement on a trolley boom of a tower crane, comprising: a frame; a drive unit fixed to the frame for winding and unwinding a trolley rope; and a sensor device fixed to the frame for determining a difference in the angle of rotation 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] The sensor system for determining the difference in rotation angle is advantageously integrated into the trolley drive. This eliminates the need for a separate sensor system on the trolley boom, thus simplifying the crane's assembly.

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

[0055] Depending on the trolley's position along the trolley arm, any bending of the trolley arm affects its rotational position. The position of the trolley cable section represents an offset of the trolley relative to a rotational angle about the tower's vertical axis. Therefore, the trolley's precise rotational position relative to the vertical axis can be determined without additional sensors.

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

[0057] Figure 1Figure 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, at least partially fixed to a base G, with an imaginary vertical axis H, and a trolley jib KA projecting from the tower T. The trolley jib KA is in the Figure 1 Not designed to be tiltable. In an example not shown, the trolley boom KA can also be designed to be tiltable, whereby the tiltable trolley boom KA is moved by means of a tilting drive.

[0058] The tower crane 2 comprises a slewing mechanism DW, for example arranged 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, for example designed 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 travels along the trolley boom KA, comprises a first and a second deflection pulley 202, 204 for deflecting a hoist rope HSL towards a load-handling device UF, which can also be referred to as a lower 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 multiple deflection pulleys for the hoist rope HSL.

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

[0061] The lifting rope HSL originates from a hoist HW and is wound over and unwound via the first deflection pulley 202 of the trolley LK, which guides a deflection pulley 302 of the load-handling device UF and the second deflection pulley 204 of the trolley LK. The lifting rope HSL is attached to a distal section 4 of the trolley boom KA.

[0062] The hoist HW comprises a brake, an electric motor, a gearbox, and a winch. The hoist rope HSL is wound onto the winch of the hoist HW to raise the load L, and it is unwound to lower the load L. The hoist rope HSL is guided, for example, from the hoist over two deflection pulleys 20 and 22 located at or near the vertical axis H to the deflection pulley 202 of the trolley LK.

[0063] A sensor device 620 is according to Figure 1The sensor unit 620 is coupled to the deflection pulley 22 and detects its deflection in the xy-plane, which changes depending on the mass m of the attached load L or the multiple pendulum below the trolley LK. The sensor unit 620 measures, for example, a tensile force exerted on the deflection pulley 22. A sensor signal determined by the sensor unit 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 from the sensor device 210 representing the distance.

[0065] A trolley drive KW, fixed to the boom KA, is connected to the trolley LK by means of a trolley cable KSL for movement along the boom KA. The trolley drive KW comprises a brake, an electric motor, a gearbox, and a double winch, the double winch having two sections connected via a common axis. When the double winch rotates in one direction, one section of the trolley cable KSL winds up, while the other section unwinds, thus moving the trolley LK.

[0066] Fixed to the frame 402 is a sensor device 420, for example a rotary angle sensor that counts the revolutions, which 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 fixed 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, fixed 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 the 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 Figure 1For clarity, the sensor device 410 is shown schematically parallel to the vertical axis z and spaced apart from the trolley cable KSL. In the embodiment described in the previous paragraph, the sensor device 410 is arranged perpendicular to the plane of the drawing and spaced apart from the trolley section 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 and determines the signal representing the difference in the angle of rotation Δθ.

[0069] The trolley drive KW comprises the frame 402 and a drive unit fixed to the frame 402 for winding and unwinding a trolley rope KSL. The sensor device 410, also fixed to the frame 402, is designed to determine the rotation angle difference Δθ between a rotation angle θ_u of the trolley boom 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 mechanism DW, the lifting mechanism HW and the trolley drive KW depending on the rotation angle 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 rotation angle difference Δθ.

[0071] A further sensor device 220, fixedly arranged on the trolley LK, particularly on 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 detects a sensor signal that characterizes an inclination of the trolley LK relative to a horizontal plane, in particular an inclination angle to a horizontal plane lying in an xh-plane spanned by the vertical and longitudinal axes of the trolley boom. The control unit 100 additionally operates the slewing mechanism DW, the hoist HW, and the trolley travel mechanism KW depending on the inclination angle Δφ.

[0072] The multiple pendulum suspended from the trolley LK is described in the following Figures 2 and 3This explains and includes the two sections HSL#1 and 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 a two-trolley operation, whereby the multiple reeving of the hoist rope results in the pendulum below it having three or more deflection pulleys on the trolleys as jib-side reference points. In this context, a multiple or double pendulum is understood to be the arrangement located below the trolley or below the trolley's deflection pulleys.

[0073] A length I_1 is determined using a sensor 610, for example a rotary angle sensor that counts revolutions, which is assigned to the hoist HW. For example, the distance between the load handling device UF and the trolley LK can be determined by detecting the rotary position of the hoist HW.

[0074] The length I_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_target are implicitly transmitted to the control unit 100 via a joystick on the operating unit 900.

[0075] Figure 2 shows a schematic illustration of the tower crane from the Figure 1 existing double pendulum. This double pendulum, which consists of all components located below the trolley LK, results in two angles. φ 1 , φ 2 of the ropes to the respective plumb line and two lengths l 1 , l 2 of the ropes.

[0076] While l 1, and the angle φ 1. which are relatively easy to measure technically, the length remains l2. The distance 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, are always variable during operation. The angle is also variable. φ 1 is not trivially measurable. And even if one considers the length l If we were to estimate 2, this would result in a not insignificant control inaccuracy, which would continue to cause the system to oscillate when the drives are actively controlled.

[0077] Figure 3 This description illustrates the simplified approach to considering multiple pendulums for preventing or reducing pendulum motion. The multiple pendulum consists of... Figure 2 It is considered a simple 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 measuring systems, because it is not a true pendulum angle. φThis pendulum angle is not found in reality on any of the objects physically encountered in crane operation. φ The value 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 Pendulum angle between the line pointing to the virtual center of gravity S of the load and the line to the perpendicular L#LK in the middle of the trolley LK; l Distance between the trolley and the virtual center of gravity S of the virtual load L; SVirtual center of gravity of the virtual load L; and mMass of the virtual load L.

[0078] Figure 4 indicates in reference to Figure 1The determination of manipulated variables or manipulated speeds u is carried out by a determination unit 110. The respective manipulated speed is specified, for example, as a percentage of the maximum speed for the respective drive. At least the sensor data and setpoints S'_setpoint are supplied to the determination unit 110 in order to determine the drive speeds u. A determination unit 120 determines the setpoints S'_setpoint as a function of the setpoints S_setpoint from the control unit 900, whereby the individual setpoints S_setpoint are multiplied by a gain factor.

[0079] Furthermore, it is possible to send an ACT signal to the detection unit 110 via the operating unit 900, which activates the detection unit and the executed control. 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] Figure 5 shows an embodiment of the investigation unit 110 from Figure 4 Means 1002 are configured to determine a first pendulum angle φ_x, which characterizes the deflection of the virtual center of mass of the multiple pendulum suspended from the trolley relative to a perpendicular passing through the trolley in a first imaginary spatial plane xh, which is spanned by the vertical axis of the tower crane. Means 1004 are configured to determine a second pendulum angle φ_y, which characterizes the deflection of the center of mass of the multiple pendulum relative to the perpendicular passing through the trolley in a second imaginary spatial plane, which is a perpendicular plane to the first spatial plane xh and runs parallel to the vertical axis H. Means 1006 determine the rotation angle θ of the trolley about the vertical axis of the tower as a function of the rotation angle θ_u of the trolley jib and as a function of the rotation angle difference Δθ.

[0081] Further means 1010 serve to determine the control variable u for operating the tower crane, in particular the slewing mechanism, the hoisting mechanism and the trolley drive, 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 rotation angle θ.

[0082] Means 1024 are set up to determine the pendulum length l as a function of the length I_1 of the sections of the lifting rope and the pre-defined and, in particular, manually adjustable length l_k of the load rope between the load-handling device and the load.

[0083] Means 1012 are set up 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 lifting 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-bearing 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-bearing device lying in the first plane as a function of the first weighting factor.

[0085] Means 1022 are set up to determine a second weighting factor ky as a function of the pendulum length l, wherein means 1004 are set up to determine the second deflection angle φ_y by weighting the deflection angle φ_1y of the section of the lifting 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-bearing device UF lying in the second plane yh as a function of the second weighting factor ky.

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

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

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

[0089] Figure 6 Another example from investigation unit 110 is shown. In contrast to the Figure 5 The detection unit 110 comprises an observer 130, to which the determined set drive speeds u and measurement signals Z are supplied. The observer determines the state vector Z~. A state controller 132 and an addition unit 134 determine the drive speeds u to be set as a function of the state vector Z~ and the setpoints S_set. For example, a transposed gain vector K' is generated by a 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 trolley, is given by Z → ˜ = x ′ φ x φ x ′ −

[0091] The control speed u_LK is then calculated as follows, for example: u LK = x soll ′ ∗ K 1 − Z → ˜ ∗ K ′ = x soll ′ ∗ K 1 − x ′ ∗ K 1 + φ x ∗ K 2 + φ x ′ ∗ K 3 = = x soll ′ ∗ K 1 − x ′ ∗ K 1 − φ x ∗ K 2 − φ x ′ ∗ K 3 = x soll ′ − x ′ ∗ K 1 − φ x ∗ K 2 − φ x ′ ∗ K 3 = − 1 ∗ x ′ − x soll ′ φ x φ x ′ ∗ K ′

[0092] In other words, differences between actual and target values ​​are formed in the state vector, Phi_target and Phi_dot_target are equal to zero, and then multiplied by the gain vector K', resulting in the scalar variable speed. The unit of

[0093] Figure 7 Figure 1 shows a schematically represented example of the construction 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 to move on rails of the trolley boom. At least two deflection pulleys 202, 204, fixed to the chassis 206, are arranged to deflect the hoist rope towards a load-handling device UF.

[0094] The sensor device 210, which is fixedly arranged on 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, which is located between the deflection pulleys 202, 204 of the trolley LK and the deflection pulley or pulleys of the load-handling device.

[0095] Each section HSL#1, HSL#2 of the lifting rope is assigned two or more sensors 214#1, 216#1; 214#2, 216#2, which are directed at the section HSL#1, HSL#2 of the lifting rope HSL from different angles.

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

[0097] On the trolley LK, sensors 214#1, 216#1, 214#2, 216#2 are arranged, for example, as ultrasonic sensors, LiDAR sensors, or other sensors for measuring the distance between the respective sensor 214#1, 216#1, 214#2, 216#2 and the associated section HSL#1, HSL#2. In the example shown, the sensors 214#1, 216#1; 214#2, 216#2 are aligned perpendicular to each other in pairs on the sections HSL#1, HSL#2 in the respective axis direction X or Y. Thus, the cable deflection relative to the sensor's position is measured.

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

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

[0100] With the measured values U 1 and U From 2 , 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: U 1 2 = X 10 2 + Y 10 2 U 2 2 = Y 10 2 + C 1 − X 10 2

[0101] Equations (1) and (2) according to Y 10 2< and X Solving for 10 2< yields: X 10 2 = U 1 2 − Y 10 2 Y 10 2 = U 2 2 − C 1 − X 10 2

[0102] Substituting equation (4) into equation (3) yields X 10 as follows: X 10 2 = U 1 2 − U 2 2 − C 1 − X 10 2 X 10 2 = U 1 2 − U 2 2 + C 1 − X 10 C 1 − X 10 X 10 2 = U 1 2 − U 2 2 + C 1 2 − 2 ⋅ C 1 ⋅ X 10 + X 10 2 X 10 2 = U 1 2 − U 2 2 + C 1 2 − 2 ⋅ C 1 ⋅ X 10 + X 10 2 0 = U 1 2 − U 2 2 + C 1 2 − 2 ⋅ C 1 ⋅ X 10 − U 1 2 + U 2 2 − C 1 2 = − 2 ⋅ C 1 ⋅ X 10 X 10 = U 1 2 − U 2 2 + C 1 2 2 ⋅ C 1

[0103] Now equation (5) is substituted into equation (4). This yields Y 10 to: Y 10 = U 2 2 − C 1 − U 1 2 − U 2 2 + C 1 2 2 ⋅ C 1 2

[0104] Now Δ X 1 and Δ Y 1. Calculate using trigonometric functions and the result from equation (6): α = arcsin Y 10 U 1 − 45 ° Δ X 1 U 1 = sin α Δ X 1 = U 1 ⋅ sin arcsin Y 10 U 1 − 45 ° α = arcsin Y 10 U 2 − 45 ° Δ Y 1 U 2 = sin α Δ Y 1 = U 2 ⋅ sin arcsin Y 10 U 2 − 45 °

[0105] Analogous to equations (7) and (8), ΔX 2 and Δ Y 2 for the opposite side, i.e., the other sensor pair is determined.

[0106] Figure 9 illustrates how the movement of the load-bearing device in the h-direction causes an additional deflection Δ X 1 or Δ X 2 of the lifting rope HSL in the x-direction arises, depending on the position of the load-handling device relative to the deflection pulleys 202, 204 of the trolley LK. Although this movement is compensated for by the measurement system, depending on the configuration, the rope may run out of the sensors' detection range when the load-handling device is close to 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 cause the lifting rope HSL to fall outside the measuring range of sensors 214#1 and 214#2, which are located in Figure 7shown, move outwards. To extend the scanning range in the x-direction in order to compensate for the deflection of the rope caused by raising and lowering the load-handling device, sensors 214, 216 can be mounted on Figure 7 They are arranged in pairs in a V-shape.

[0107] Figure 10 Figure 1 shows the aforementioned V-shaped arrangement of 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 described below. Figure 1 and 7 to be seen. 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, sections HSL#1 and HSL#2 of the lifting rope are located between sensors 214 and 216. In an alternative example not shown, sensors 214 and 216 are located at least partially, and in particular entirely, between sections HSL#1 and HSL#2 of the lifting rope.

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

[0110] The angles are calculated according to equations (9) and (10): U 1 2 = X 10 2 + Y 10 2 U 2 2 = X 10 2 + C 1 − Y 10 2

[0111] Equations (9) and (10) according to Y 10 2< and X Solving for 10 2< yields: Y 10 2 = U 1 2 − X 10 2 X 10 2 = U 2 2 − C 1 − Y 10 2

[0112] Substituting equation (11) into equation (12) yields Y 10 to: Y 10 2 = U 1 2 − U 2 2 − C 1 − Y 10 2 Y 10 2 = U 1 2 − U 2 2 + C 1 − Y 10 2 Y 10 2 = U 1 2 − U 2 2 + C 1 2 − 2 ⋅ C 1 ⋅ Y 10 + Y 10 2 0 = U 1 2 − U 2 2 + C 1 2 − 2 ⋅ C 1 ⋅ Y 10

[0113] After Y Solving 10 yields: Y 10 = U 1 2 − U 2 2 + C 1 2 2 ⋅ C 1

[0114] The calculated size Y 10 is substituted into equation (12) to X To calculate 10: X 10 = U 2 2 − C 1 − Y 10 2 Δ Y 1 = C 1 2 − Y 10

[0115] To Δ X To calculate 1, the height H of the associated isosceles triangle will be calculated. H 2 = a 2 + C 1 2 2 H = a 2 + C 1 2 2

[0116] For Δ X This results in 1: Δ X 1 = X 10 − H = X 10 − a 2 + C 1 2 2

[0117] Analogous to equations (14) and (17) Δ X 2 and Δ Y 2 calculated for the opposite section of the hoist rope.

[0118] Figure 12 illustrates that the different lengths result from the unwinding behavior of the lifting rope over the deflection pulleys 202, 204. L 1 and l Two of the sections HSL#1 and HSL#2 of the lifting rope up to a sensor axis 222 are created. This is compensated for by equation (18). The mean rope length L thus remains constant. L = L 1 + L 2 2

[0119] The distances Δ determined using equations (7) and (8) or (14) and (17). X 1 and Δ Y 1 or Δ X 2 and Δ Y 2 are now converted into angles over the known and constant rope length from (18) to the pulley 202, 204.

[0120] The uncompensated angle φ ux Equation (19) describes the deflection of the load relative to the trolley in the x-direction. Due to the inclination of the trolley LK, a deviation occurs from the absolute angle of sections HSL#1 and HSL#2 of the hoist rope relative to the vertical through the trolley LK. The resulting uncompensated angle φ ux This is therefore compensated for. φ ux = arctan Δ X 1 L + arctan Δ X 2 L 2

[0121] Similarly, the angle φ 1 y determined according to equation (20). This describes analogously to the angle φ ux The load's displacement in the y-direction. However, compensation is not necessary here. φ 1 y = arctan Δ Y 1 L + arctan Δ Y 2 L 2

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

[0123] With the determined inclination angle Δφ, the angle can now be calculated. φ ux to φ 1x to be compensated: φ 1 x = φ ux − Δ φ

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

[0125] The different sensor devices 210 and 310 from Figure 1 The measured deflection angles are compared with the factors kx : (0≤kx ≤1) and ky : (0≤ky ≤1) The aforementioned factors weight the influence of each angle on the sensor fusion result. The respective factor is adjusted depending on the pendulum length l to minimize unwanted oscillations in the sensor data at extreme ranges. For long rope lengths (>50 m), the sensor data from the sensor device on the trolley is superimposed by the natural oscillation of the rope sections of the hoist rope. Conversely, for short rope lengths (<10 m), the sensor data from the sensor device on the load-handling device is superimposed by the pronounced oscillation of the lower block – especially when empty – due to its natural oscillation. Accordingly, the pendulum angles, which correspond to a virtual rope angle up to the virtual load (see...), are adjusted. Figures 2 and 3, determined according to equations (22) and (23): φ x = k x φ 1 x + 1 − k x φ 2 x φ y = k y φ 1 y + 1 − k y φ 2 y

[0126] The pendulum length l results from the definable length LK to: l = l 1 + l K

[0127] By fusion of the individual sensor data carried out in equations (22) and (23), unwanted phase-shifted vibrations are reduced or eliminated.

[0128] The vibrations caused by the load-handling device are recorded with a phase shift on the trolley and the load-handling device, respectively, and are advantageously eliminated by addition in equations (22) (23). This is important because it frequently happens that the two endpoints of the double pendulum (in this case the trolley and the load) do not move and only the middle part of the double oscillator (in this case the lower block or the load-handling device) still oscillates.

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

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

[0131] In Figure 14 It is shown how the elastic movement of the trolley boom KA creates a difference between the rotation angle θ of the trolley LK and thus the load relative to the longitudinal axis A_KA of the trolley boom KA compared to the rotation angle θ u of tower T to the cat-shaped extension KA.

[0132] The sensor device 410 for determining a rotation angle difference Δθ comprises according to Figure 14 The two sensors 412a and 412b are fixed to the trolley boom in the imaginary plane xy, with section KSL#1 of the trolley cable located between them. Sensors 412a and 412b determine their respective distances to 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. Sensors 412a and 412b can be configured, for example, as ultrasonic sensors, LiDAR sensors, or other sensors for measuring the distance between sensors 412a, 412b and section KSL#1 of the trolley cable.

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

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

[0135] The control system shown in Figure 4a will now be discussed in general terms using a state-space representation. In state-space representation, linear systems of order n are decomposed into n first-order subsystems to simplify the mathematical description and design of the state controller. The trolley drive, 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 comprises the hoist rope, load-handling device, lifting slings, and load. Both systems, considered separately, represent a doubly integrating system. They are coupled because any movement of the trolley always results in a movement of the multiple pendulum.The feedback effect of the multiple pendulum movements will be neglected here, since the frequency converter regulates the speed of the trolley and thus prevents the feedback effect on the trolley.

[0136] The controller design is based on a mathematical description derived from the system analysis of the multi-input system. The differential equations are expressed in matrix and vector form and can be transformed using matrix operations. This yields the system's eigenvalues, which in this case reveal the system's instability. Using the pole selection method, a desired system is created based on newly chosen eigenvalues, exhibiting stable behavior and the desired dynamics. The difference between the real, unstable system and the desired system is then addressed 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 pre-filter value. The sum of these products is the desired manipulated variable. In simplified terms, one could speak of four superimposed proportional (P) controllers. It is immediately apparent from this that the state controller has no integral (I) or derivative (D) components. The latter are only present insofar as one state variable can be the differential of another. Thus, derivative components then also influence the control process.

[0138] Figure 15Figure 2 shows a signal flow diagram relating to the trolley, derived from the following equation (29). The trolley's velocity u_LK corresponds to a value at the controller output and responds to a step change in the manipulated variable with first-order lag behavior. First, the linearized fourth-order process model is described. The four state variables are defined as follows: xLK position x' = v LK speed φ x pendulum angle φ x ' Pendulum angular velocity: φ x ' can be obtained either with an observer or by numerical derivation: φ x ′ k = φ x k − φ x k − 1 T a T a Sampling time.

[0139] The following process values ​​are required to simulate the process and design the state controller: T Stell Time constant of the PT1 element, which controls the actuator (frequency converter + geared motor + mass inertias); lPendulum length as distance to the load center S.

[0140] As already mentioned, the step function of the rotational speed can be approximated by that of a first-order lag element (PT1 element). Therefore, the step function of the trolley's speed is: x ′ = u LK ⋅ K ⋅ 1 − e − t T

[0141] K and T The parameters of the first-order lag element (PT1 element) are determined below. The derivative of equation (26) yields the LK acceleration: x " = u LK ⋅ K T ⋅ e − t T

[0142] Equation (27) is then e − t T solved and substituted into (26), which yields: T ⋅ x " + x ′ = K ⋅ u LK x " = K T ⋅ u LK − 1 T ⋅ x ′

[0143] Based on the Figure 16 The motion of the pendulum system is examined. The focus is on the suspended multiple pendulum (see Figures 2 and 3 (as described above) two forces act: The downward force of gravity F g and the rope force F sThe 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 sums of which, according to Newton's law of equilibrium, each equal zero. New auxiliary variables are: x_Last horizontal position of the virtual center of gravity of the load or multiple pendulum; and h_Last vertical position of the virtual center of gravity of the load or multiple pendulum

[0144] The horizontal forces and vertical forces result according to equations (30) and (31): m ⋅ x _ Last " + F s ⋅ sin φ x = 0 − m ⋅ g + m ⋅ h _ Last " + F s ⋅ cos φ x = 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_Last and h_Last) can be eliminated. Extending equation (30) with cos(φ x ) and (31) with sin(φ x ), so you get: m ⋅ x _ Last " ⋅ cos φ x + F s ⋅ sin φ x ⋅ cos φ x = 0 − m ⋅ g ⋅ sin φ x + m ⋅ h _ Last " ⋅ sin φ x + F s ⋅ cos φ x ⋅ sin φ x = 0

[0146] Subtracting (32) from (33) gives the rod force F s removed. The result is then divided by the load mass m, and this is also removed: x _ Last " ⋅ cos φ x − h _ Last " ⋅ sin φ x = − g ⋅ sin φ x

[0147] The coordinates of the load ( x_Last and h_Last) are eliminated using the transformation equations: x _ Last = x + l ⋅ sin φ x h _ Last = l ⋅ cos φ x

[0148] Since the variables x_Last and h_Last Since they appear in their second derivative in (34), they must be differentiated twice: x _ Last ′ = x ′ + l ⋅ φ x ′ ⋅ cos φ x h _ Last ′ = − l ⋅ φ x ′ ⋅ sin φ x x _ Last " = x " + l ⋅ φ x " ⋅ cos ϕ − l ⋅ φ x ′ 2 ⋅ sin φ x h _ Last " = − l ⋅ φ x " ⋅ sin ϕ − l ⋅ φ x ′ 2 ⋅ cos φ x

[0149] The equations for x_Last" and h_Last" (38) are substituted into (39). This yields the nonlinear differential equation of the pendulum system: x " ⋅ cos φ x + l ⋅ φ x " = − g ⋅ sin φ x

[0150] To linearize this differential equation, the pendulum angle is used. φ x assumed to be very small: φ x ≪ 1 = > sin φ x ≈ φ x und cos φ x ≈ 1 und φ x ′ 2 ≈ 0 x " + l ⋅ φ x " = − g ⋅ φ x

[0151] The linearized differential equation (40) is solved according to φ x " resolved (41) and is represented as a signal flow diagram in Figure 17 depicted. φ x " = - g l ⋅ φ x − 1 l ⋅ 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 substituted. This allows the previously shown signal flow diagrams to be linked. Substituting equation (29) into (41) yields: φ x " = - g l ⋅ φ x − K T ⋅ l ⋅ x _ Last + 1 T ⋅ l ⋅ x ′

[0153] To describe the system in state space, the linear differential equations are transformed into state equations. For this purpose, the variables are x, x', φ x and φ x ' through the state variables q = [ q 0, q 1, q 2, q 3] replaced: x " = K T ⋅ u LK − 1 T ⋅ x ′ φ x " = − g l ⋅ φ x − K T ⋅ l ⋅ u LK + 1 T ⋅ l ⋅ x ′

[0154] For a clearer, concise form, vectors and matrices are introduced. This yields the vector differential equation for state variables: x ′ x " φ x ′ φ x " = 0 1 0 0 0 − 1 T 0 0 0 0 0 1 0 1 l ⋅ T − g l 0 ⋅ x x ′ φ x φ x ′ + 0 K T 0 − K l ⋅ T ⋅ u LK

[0155] The controller receives as its setpoint the desired speed of the trolley in the range of -100 to 100% of the nominal speed with an accuracy of Δ V = 100 % 20000 = 0.005 % = 8.3 mm s and regulates the speed of the trolley without amplification, from which it follows K = K stg = 1. The actual rotational speed follows the target value with a delay of T = T stg = 0.2 s.

[0156] To enable pendulum-free positioning, a state controller is used that transforms the undamped real system into a sufficiently damped desired system. For this purpose, numbers are first inserted into the input and system matrices: T = T stg = 0.2 s ; K = K stg = 1; l : variable. A LK = 0 1 0 0 0 − 5 0 0 0 0 0 1 0 5 l − 9.81 l 0 B LK = 0 5 0 − 5 l

[0157] In assisted control, the trolley's speed is the controlled variable. The controller ensures that the trolley follows the speed setting with as little oscillation as possible. In this case, the trolley's position is irrelevant; the state-space representation can be reduced to this state variable. The new matrix representation is: A LK = − 5 0 0 0 0 1 5 l − 9.81 l 0 B LK = 5 0 − 5 l

[0158] To design a controller, a rope length corresponding to the pendulum length l is assumed: e.g. for l For 5 m, the following matrix representation results: A LK = − 5 0 0 0 0 1 1 − 1.962 0 B LK = 5 0 − 1

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

[0160] Alternatively, a simulation tool can be used: eig A = 1.4007 i − 1.4007 i − 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 two poles is 0.

[0162] For digital control, a discrete representation is required, which can be obtained in Matlab, for example, with the following command: Ad Bd Cd Dd = c 2 d A B C D T a ;

[0163] For T a = 0.1 s : Ad = 0.7788 0 0 0.0023 0.9902 0.0997 0.0441 − 0.1956 0.9902 Bd = 0.2212 − 0.0023 − 0.0441

[0164] The eigenvalues ​​for discrete representation are given by: EWd = eig Ad = 0.9902 + 0.1396 i 0.9902 − 0.1396 i 0.7788 abs EWd = 1 1 0.7788

[0165] The first and second complex poles lie on the unit circle, which also indicates an oscillating system. To achieve the desired pendulum-free system, the latter is defined by specifying its eigenvalues. Thus, the poles of the system are specified (pole specification). The poles are positioned so that the available acceleration torque is not exceeded. The closer the poles are chosen to the center of the unit circle, the more dynamic the desired system becomes and the larger the maximum deflection angle during the acceleration phase, which negatively affects the steel structure. Therefore, an optimum is determined as a compromise, taking both aspects into account. Should the cable length or pendulum length l change, the eigenvalues ​​and the resulting controller are also recalculated or updated.

[0166] As an alternative to pole selection, 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 given state weights Q.

[0167] Based on the Figures 18 and 19 A system analysis of the slewing mechanism is performed. The four state variables of the slewing mechanism 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: I A ⋅ θ " = M − M R , using the following sizes: IA Moment of inertia acting on the slewing mechanism; drive torque of the slewing mechanism; MRCounter-moment; MR=FR⋅x MR=m⋅yL"⋅x FR=sinφy⋅m⋅g IA⋅θ"=M−sinφy⋅m⋅g⋅x

[0169] The equations of motion for the load are: m ⋅ y L " = y − m ⋅ g m ⋅ z L " = F R

[0170] The equation of motion for the load in Y The directions result in: y L = y + l ⋅ sin φ y y L ′ = y ′ + l ⋅ cos φ y ⋅ φ y ′ y L " = y " − l ⋅ sin φ y ⋅ φ y ′ 2 + l ⋅ cos φ y ⋅ φ y "

[0171] The equations of motion for the load in the Z-direction are: z L = l − l ⋅ cos φ y z L ′ = l ⋅ sin φ y ⋅ φ y ′ z L " = l ⋅ cos φ y ⋅ φ y ′ 2 + l ⋅ sin φ y ⋅ φ "

[0172] Equations (55) and (56) together yield I A ⋅ θ " = M − m ⋅ x ⋅ y L "

[0173] Substituting equation (58) into (60) yields: I A ⋅ θ " = M − m ⋅ x ⋅ y " − l ⋅ sin φ y ⋅ φ y ′ 2 + l ⋅ cos φ y ⋅ φ y " I A m ⋅ x ⋅ θ " = M m ⋅ x − y " + l ⋅ sin φ y ⋅ φ y ′ 2 − l ⋅ cos φ y ⋅ φ y "

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

[0175] With the angle of rotation θSubstituting the radian measure into the y" field yields: I A m ⋅ x ⋅ θ " = M m ⋅ x − x ⋅ θ " + l ⋅ sin φ y ⋅ φ y ′ 2 − l ⋅ cos φ y ⋅ φ y " I A m ⋅ x ⋅ θ " + x ⋅ θ " = M m ⋅ x + l ⋅ sin φ y ⋅ φ y ′ 2 − l ⋅ cos φ y ⋅ φ y " I A m ⋅ x + s ⋅ θ " = M m ⋅ x + l ⋅ sin φ y ⋅ φ y ′ 2 − l ⋅ cos φ y ⋅ φ y "

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

[0177] Adapted to the turning mechanism, the following results: φ x → φ y x " → y " = x ⋅ θ "

[0178] The second differential equation yields: l ⋅ φ y " = − x ⋅ θ " ⋅ cos φ y − g ⋅ sin φ x

[0179] To linearize the differential equations, the pendulum angle φ is used. y assumed to be very small: φ x ≪ 1 = > sin φ x ≈ φ x und cos φ x ≈ 1 und φ x ′ 2 ≈ 0

[0180] The control variable corresponds to the drive torque of the rotary drive: M = u DW θ " = m ⋅ x ⋅ g I A ⋅ φ y + 1 I A ⋅ u DW 1 . DGL φ y " = − m ⋅ x 2 ⋅ g l ⋅ I A + g l ⋅ φ y − x l ⋅ I A ⋅ u DW 2 . DGL

[0181] In state-space representation, this results in: θ ′ θ " φ y ′ φ y " = 0 1 0 0 0 m ⋅ x ⋅ g I A 0 0 0 0 0 1 0 − m ⋅ x 2 ⋅ g l ⋅ I A + g l − g l 0 ⋅ θ θ ′ φ y φ y ′ + 0 1 I A 0 − x l ⋅ I A ⋅ u DW A DW = 0 1 0 0 0 m ⋅ x ⋅ g I A 0 0 0 0 0 1 0 − m ⋅ x 2 ⋅ g l ⋅ I A + g l − g l 0 B DW = 0 1 I A 0 − x l ⋅ I A

[0182] The controller design for the slewing mechanism (Y-direction) and the hoist operates on essentially the same principle. This results in a crane model in state space consisting of three states for the trolley model, four states for the slewing mechanism model, and two states for the hoist model: States: Z → = x ′ φ x φ x ′ θ θ ′ φ y φ y ′ l l ′ ; x " φ x ′ φ x " θ ′ θ " φ y ′ φ y " l ′ l " = A LK A DW → A LK 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 A DW 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 A HW ⋅ x ′ φ x φ x ′ θ θ ′ φ y φ y ′ l l ′ + 0 0 0 B LK 0 0 0 0 0 0 0 0 0 0 0 0 B DW 0 0 0 0 0 B HW 0 0 ⋅ u LK u DW u HW

[0183] The controller uses, for example, the current position of the load relative to the horizontal tower axes or the speeds of the load as a controlled variable.

[0184] The respective target values x soll ′ , θ should , l should or S should are integrated from the joystick inputs of the control unit. The rotational speed is then... u LK , u DW , u HWThe joystick input of the respective drive (trolley, slewing, and hoist) is used as a reference to achieve either the target speed or the target position of the load. The joystick input can be either incremental or a percentage of the maximum speed. The following equations refer to the examples of... Figures 5 and 6 . S soll → = x soll ′ θ soll l soll u → = u LK u DW u HW Z → = x φ x θ φ y l l ′ ; Z → ˜ = x ′ φ x φ x ′ ˜ θ θ ′ φ y φ y ′ ˜ l l ′ ;

[0185] In the control loop, the future movements of the measured variables are calculated using the crane model (72). x' φ x θ θ' φ yl calculated. Based on this, 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 that only allows damping of the vibration, an optimal trajectory of the movement (neutralizing any oscillation leading to pendulum motion) of the load is calculated based on the available (fused) sensor and model data, so that no strong pendulum motion caused by the crane operator or by the crane operation can occur.

[0187] Subsequent damping of the oscillating pendulum system is therefore not necessary, or a control range tailored to this is very limited and can be implemented effectively.

[0188] After the control system is activated by specifying a setpoint, the controller enters an acceleration phase. During this phase, not only are the initial oscillations caused by the initial movement eliminated, but also the initial oscillation itself. Following this, as long as the setpoint (stage) remains constant, the constant speed phase begins, where the load moves at a constant speed without any oscillation. Each change in the setpoint or stage then initiates another acceleration or deceleration phase.

[0189] The control system is also activated by a pulsed movement of the control panel. In this case, only the initial pendulum motion is corrected. The correction time can be usefully limited to one pendulum period. As is known, the pendulum period depends only on the length and is calculated using the following formula: T = 2 ⋅ π ⋅ l g

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

[0191] The second computing unit 160 is communicatively coupled to the first computing unit 150. In step 162, the second computing unit 160 waits for a message from the first computing unit, S_1, i.e., it waits for a control telegram from the PLC. The first computing unit 150 periodically sends messages with current control commands and sensor data to the second computing unit 160. If the message contains target values, which are specified by the first computing unit 150, for example, via joystick input from the control panel or the radio remote control, then, starting from step 164, block 110 is executed. Figure 1 The switch was made and the regulation was executed. In step 166, it is checked whether manual activation of the regulation was requested. If so, block 110 is activated.

[0192] In step 168, it is checked whether a readjustment is necessary. For example, if no message is received from the first processing unit, it is checked whether actual values ​​or derived values ​​exceed a predefined threshold. If this is the case, block 110 is activated. The requirement for readjustment is triggered, for example, if the rotation angle θ of the trolley LK, the first pendulum angle, or the second pendulum angle exceeds its respective assigned threshold. Readjustment is therefore performed if the load's movement has not yet ceased after the absence of a control command. To prevent the load from oscillating, a follow-up movement of the load is initiated.

[0193] Block 110 determines control variables, which are transferred to the first processing unit in step 170 to be forwarded to the crane drives. The determination of the control variables u_LK, u_DW, u_HW via block 110 is therefore activated when at least one of the following conditions occurs: 164 the setpoint S'_setpoint is not equal to zero; 166 a manual activation of the control variable determination 110 originating from an operating unit 900; and 168 a request for adjustment.

Claims

1. A trolley (LK) for a tower crane (2) comprising: a chassis (206) for moving the trolley (LK) along a trolley jib (KA); at least two deflection pulleys (202, 204) fixed to the chassis (206) for deflecting a hoist rope (HSL) towards a load handling device (UF); and a sensor device (210) fixed 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 handling device (UF) relative to the vertical passing through the trolley (LK).

2. The trolley (LK) according to claim 1, 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).

3. The trolley (LK) according to claim 1, wherein the sensor device for detecting the rope angle φ_1 is designed as an ultrasonic sensor or LiDAR sensor.

4. The trolley (LK) according to one of claims 1 to 3, 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 lifting rope (HSL), which are directed at the section (HSL#1, HSL#2) of the lifting rope (HSL) from different angles.

5. The trolley (LK) according to one of claims 1 to 4, wherein the sensor device (210) is arranged at least partially between the at least two sections (HSL#1, HSL#2) of the lifting rope (HSL).

6. The trolley (LK) according to one of claims 1 to 5 comprising: at least one further sensor device (220) fixedly arranged to the chassis (206) for generating at least one further sensor signal which characterizes an inclination of the trolley (LK) to a horizontal.

7. A trolley boom (KA) with a trolley drive (KW) and a trolley (LK) according to any one of claims 1 to 6, which is connected to the trolley drive (KW) by means of a trolley rope (KSL), wherein the trolley drive (KW) is provided for arrangement on a trolley boom (KA) of a tower crane (2), comprising: a frame (402); a drive unit fixed to the frame (402) for winding and unwinding a trolley rope (KSL); and a sensor device (410) fixed 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).

8. Trolley boom (KA) according to claim 7, 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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