CONCRETE PUMP

Description

[0001] The present invention relates to a concrete pump comprising a delivery pump, a concrete line, and an articulated arm forming a placing boom, along which the concrete line is guided. The articulated arm has a swivel base rotatable about a vertical axis and / or at least one segment pivotable about a horizontal axis by means of a joint. The swivel base is movable about the vertical axis via an actuator, and / or the at least one segment is pivotable about the horizontal axis via an actuator. The concrete pump further comprises a control unit for controlling the actuators of the placing boom, the control unit including a disturbance variable compensation function to reduce the vibrations of the placing boom induced by the concrete delivery. In particular, the concrete pump is a truck-mounted concrete pump.

[0002] The relevant state of the art is explained in detail in the introductory section of the figure description. In particular, DE 101 01 570 B4 discloses a disturbance feedforward combined with feedback-based vibration damping based on the principle of a virtual spring-damper element, which is intended to describe a hydraulic cylinder of the articulated arm. The disturbance feedforward is to be implemented using pressure or flow sensors in the conveying line.

[0003] WO 2016 131977 A1 uses an inertial measurement unit to control the position of the boom tip of a concrete pump. Vibration damping is also described.

[0004] The object of the present invention is to provide a concrete pump with improved disturbance variable control.

[0005] This problem is solved by a concrete pump according to claim 1.

[0006] Preferred embodiments of the present invention are the subject of the dependent claims.

[0007] The present invention comprises a concrete pump with a delivery pump, a concrete line, and an articulated arm forming a placing boom, along which the concrete line is guided. The articulated arm has a swivel base rotatable about a vertical axis and / or at least one segment pivotable about a horizontal axis by means of a joint. The swivel base is movable about the vertical axis via an actuator, and / or the at least one segment is pivotable about the horizontal axis via an actuator. The concrete pump further comprises a control unit for controlling the actuators of the placing boom, the control unit including a disturbance variable compensation system for reducing the vibrations of the placing boom induced by the concrete delivery. According to the invention, the disturbance variable compensation system estimates the disturbance forces from measured values ​​of the position and / or vibration state of the placing boom via a disturbance observer.

[0008] This has the advantage that no operating parameters of the concrete pumping system are required, which would otherwise have to be determined through complex measurements. Instead, the sensors already present for controlling the articulated arm, which describe the position and / or vibration state of the placing mast, can also be used for the disturbance variable detection.

[0009] According to the present invention, the disturbance feedforward is based on a modal model that describes the vibration mode of the disturbance forces. Compared to a physically motivated approach, this method has the advantage that the disturbance feedforward automatically adapts to the position of the articulated arm.

[0010] According to the invention, the modal model comprises a fundamental frequency and one or more multiples of the fundamental frequency. It is provided that the pumping frequency of the feed pump is incorporated into the modal model as the fundamental frequency.

[0011] In one possible embodiment of the present invention, the disturbance feedforward determines the initial state of the modal model from the measured values ​​of the position and / or the vibration state of the distribution mast.

[0012] This can be done in particular by an observer who estimates the vibration state generated by the perturbing forces, especially by estimating the phase position and amplitude of the modes of the modal model.

[0013] In one possible embodiment of the present invention, the disturbance variable feedforward is further based on a physical model of the distribution mast, which describes the influence of the disturbance forces on the vibration state of the distribution mast.

[0014] Preferably, the physical model of the distribution mast takes into account the elastic deformation of at least one of the segments and preferably several, more preferably all segments of the articulated arm.

[0015] In one possible embodiment of the present invention, the disturbance variable control system controls the actuators of the distribution mast based on the estimated disturbance forces.

[0016] Preferably, the disturbance variable control controls the actuators in such a way that the influence of the disturbance forces on a point of the distribution mast, in particular the tip of the distribution mast, is reduced and preferably eliminated.

[0017] In one possible embodiment of the present invention, the control system estimates the system state based on a modal model of the disturbance forces and a physical model of the distribution mast. In particular, the modal model described above is used for this purpose. Furthermore, the modal model can be coupled to the physical model in such a way that the physical model describes the influence of the disturbance forces on the vibration state of the distribution mast.

[0018] In one possible embodiment of the present invention, at least one operating parameter of the feed pump and / or the concrete delivery is included in the disturbance variable feedforward. In particular, the pump frequency of the feed pump is included in the disturbance variable feedforward.

[0019] Preferably, the disturbance variable feedforward determines the pumping frequency of the feed pump from the control parameters and / or control signals for the feed pump.

[0020] In one possible embodiment of the invention, the pumping frequency of the feed pump represents the only operating parameter of the feed pump and / or the concrete delivery that is included in the disturbance variable feedforward.

[0021] The pump is preferably a double-piston pump. Such a double-piston pump comprises two pistons that operate in opposite directions to pump the concrete. Pumps of this type are known.

[0022] The damping of induced vibrations by the disturbance variable feedforward according to the present invention is based on the control of the actuators of the articulated arm.

[0023] In contrast, the control of the feed pump is preferably independent of the disturbance feedforward. In particular, the disturbance feedforward can be based solely on the control of the actuators of the articulated arm.

[0024] In one possible embodiment of the present invention, the control system comprises, in addition to the disturbance variable feedforward, a control system which is based on a measurement and / or feedback of the position and / or vibration state of the distribution mast.

[0025] In particular, the regulation includes vibration damping for damping horizontal and / or vertical vibrations of the distribution mast, which is based on a measurement and / or feedback of the position and vibration state of the distribution mast. Specifically, the vibration damping can be designed to dampen the natural vibrations of the distribution mast.

[0026] Preferably, the vibration damping is based on a physical model of the placing boom. In particular, this physical model can be the same model that is also used to determine the influence of the disturbance forces of concrete conveying on the placing boom.

[0027] In one possible embodiment of the present invention, the estimation of the disturbance forces is based on the signals of at least one sensor, whose signals are also used by the control and / or vibration damping.

[0028] Preferably, several sensors are used, which are used by means of disturbance variable feedforward to determine the position and / or vibration state of the distribution mast in order to estimate the disturbance forces, also used by the control and / or vibration damping.

[0029] Furthermore, the same sensors are preferably used for disturbance feedforward and for control and / or vibration damping.

[0030] In one possible embodiment of the present invention, the disturbance feedforward and the control and / or vibration damping are based on the same values ​​for the state of the articulated arm, in particular for the position and / or vibration state of the articulated arm. In particular, an observer is provided which estimates the state of the articulated arm, in particular its position and / or vibration state, and whose output variables are used by both the disturbance feedforward and the control and / or vibration damping.

[0031] In one possible embodiment of the present invention, the concrete pump comprises at least one rotation rate sensor which is arranged on a segment of the articulated arm, wherein the control for disturbance input and / or vibration damping determines a vibration state of the entire distributor mast based on the measured values ​​of the rotation rate sensor from the vibrations of the individual segments.

[0032] In one possible embodiment of the present invention, the concrete pump comprises at least one rotation rate sensor which is arranged on a segment of the articulated arm, wherein the control for disturbance input and / or vibration damping is carried out without the use of geodetic sensors and / or deformation sensors.

[0033] In one possible embodiment of the present invention, the concrete pump comprises at least one rotation rate sensor which is arranged in a front region of a segment which is arranged between the swivel bracket and a segment forming the mast tip in the articulated arm.

[0034] Preferably, the signal from the gyroscope is used to determine vibrations of the segment on which it is located. For the purposes of this invention, the front region of a segment is preferably considered to be the front 25% of the segment's length, i.e., the 25% closest to the mast tip, or more preferably, the front 10%.

[0035] In one possible embodiment of the present invention, angular rate sensors are arranged on at least two segments. Preferably, the signals from these angular rate sensors are used to determine vibrations of the segments on which they are arranged.

[0036] Preferably, the disturbance feedforward and / or the vibration damping determines a vibration state of the segments and / or the entire arm based on the measured values ​​of the at least two angular rate sensors.

[0037] Preferably, the gyroscopes are arranged in a front area of ​​the segments. This improves the detection of vibrations in these segments.

[0038] Preferably, the at least two segments on which the gyroscopes are arranged are positioned between the swivel bracket and a segment forming the mast tip in the articulated arm. More preferably, a further gyroscope is arranged on the segment forming the mast tip, which is preferably used to determine vibrations of the mast tip.

[0039] In one possible embodiment of the present invention, the articulated arm further comprises sensors assigned to the rotary joints for the indirect or direct measurement of the respective rotation angle of the joint, wherein the measurement signals of the sensors are incorporated into the control of the articulated arm. Preferably, these sensors are provided in addition to the angular rate sensors and can be used, in particular, to compensate for a drift in the measured values, which is unavoidable in angular rate sensors due to their design.

[0040] The sensor signals are preferably used for disturbance feedforward and / or vibration damping. Alternatively or additionally, the sensor signals can be used to determine the current position of the articulated arm, and in particular for position control of the articulated arm.

[0041] In one possible embodiment of the present invention, disturbance feedforward and / or vibration damping is achieved using a physical model of the distribution mast, in which the flexibility of at least one segment is described by a virtual joint arranged within this segment.

[0042] Preferably, at least the flexibility of the segment directly attached to the swivel head is taken into account by a corresponding virtual joint, since the vibrations of this segment have the greatest influence on the vibration state of the articulated arm. Alternatively or additionally, the flexibility of the last segment, which forms the mast tip, can be considered. This is usually the least stable and therefore the most flexible. However, the virtual joint can also be located in a different segment.

[0043] Preferably, the flexibility of several and, more preferably, all segments is described by at least one virtual joint arranged within the respective segment.

[0044] In one possible embodiment of the present invention, the physical model is a rigid body model with actuated joints. Preferably, the model describes several, and more preferably all, segments of the articulated arm, thus simultaneously representing the position of the articulated arm. The oscillatory capability of at least one, and more preferably several, and more preferably all segments is then described by at least one virtual joint in the rigid bodies describing the actual segments.

[0045] In one possible embodiment of the present invention, a spring element and a damper element are assigned to the virtual joint. This allows the flexibility of the segment to be described. Preferably, the spring constant and the damper constant are selected such that the virtual joint describes the magnitude of the deflection and / or torsion and / or the first natural frequency of the real segment. The virtual joint can therefore be considered a first description of the first natural frequency of the segment in terms of frequency and amplitude.

[0046] In one possible embodiment of the present invention, fewer than 10, more preferably fewer than 5, more preferably fewer than 3, and in another possible embodiment exactly one virtual joint are provided within the segment. This reduces the complexity of the model.

[0047] If only a vertical or horizontal vibration needs to be considered, a virtual joint with only one axis of rotation is sufficient. In particular, a virtual joint with a horizontal axis of rotation can be used to dampen vertical vibrations.

[0048] In a preferred embodiment of the present invention, however, the virtual joint has at least two and preferably three degrees of freedom of movement.

[0049] In one possible embodiment of the present invention, the disturbance variable feedforward and / or vibration damping takes into account a torsion of at least one segment and / or the articulated arm.

[0050] In one possible embodiment of the present invention, the torsion of at least one segment and / or the articulated arm is taken into account by using a physical model of the articulated arm that describes a torsion of the articulated arm and / or one or more segments of the articulated arm. More preferably, this is done via a virtual pivot joint, as described above, which extends in the longitudinal direction of the segment.

[0051] In one possible embodiment of the present invention, the articulated arm comprises at least two angular rate sensors arranged on different segments, wherein the torsion is determined from a comparison of the measured values ​​of the angular rate sensors.

[0052] For example, the measured values ​​of a first gyroscope located closest to the swivel within the articulated arm can be compared with the measured values ​​of a second gyroscope located closest to the mast tip within the articulated arm to determine the torsion of the articulated arm between the two gyroscopes.

[0053] Alternatively or additionally, the measured values ​​of a first gyroscope, located on a first segment, can be compared with the measured values ​​of a second gyroscope, located on a segment following the first segment within the articulated arm, in order to determine the torsion of the articulated arm between the two gyroscopes and, in particular, the torsion of the first or second segment. For this purpose, the gyroscopes can, for example, each be located in a front region of the segments.

[0054] Alternatively or additionally, the articulated arm can include at least two gyroscopes arranged at different positions on the same segment, with the segment's torsion being determined by comparing the measured values ​​of the gyroscopes. Preferably, the gyroscopes are arranged in a front and a rear region of the segment.

[0055] Furthermore, at least one of the gyroscopes used to determine the torsion can be located on the swivel and / or in a rear area of ​​the segment directly attached to the swivel, and / or at least one of the gyroscopes used to determine the torsion can be located on the last segment of the articulated arm and in particular in the area of ​​the mast tip.

[0056] Preferably, the angular rate sensors, whose measured values ​​are used to determine the torsion, have at least two sensitivity directions, in particular a first horizontal sensitivity direction and a second sensitivity direction running in a vertical plane. This allows the torsion to be determined relatively easily by comparison.

[0057] However, even independently of the determination of the torsion, the rotation rate sensors, whose measured values ​​are incorporated into the disturbance variable feedforward and / or vibration damping according to the invention, preferably have at least two sensitivity directions, in particular a first horizontal sensitivity direction and a second sensitivity direction running in a vertical plane.

[0058] InIn one possible embodiment of the present invention, the control system for the articulated arm comprises an observer who estimates the state of the articulated arm. In particular, the observer can comprise a physical model of the articulated arm and estimate its state based on the model and on measured values ​​from sensors.

[0059] Preferably, the estimation is based on the measured values ​​from sensors as described above, in particular on the basis of at least one rotation angle sensor and / or sensors assigned to the joints for the indirect or direct detection of the rotation angles of the joints.

[0060] Preferably, the observer uses a physical model of the articulated arm, as described in more detail above, in particular a physical model which is also used to determine the influence of the disturbance forces on the articulated arm through the disturbance feedforward.

[0061] The observer preferably assesses the position and / or the state of vibration of the articulated arm.

[0062] Preferably, the observer's output variables are incorporated into the disturbance feedforward and / or vibration damping.

[0063] When, within the scope of the present invention, it is referred to as determining a state, this includes in particular an estimation of the state by an observer.

[0064] According to the invention, vibration damping could, in one possible embodiment, be achieved solely as feedforward control. Preferably, however, the vibration damping comprises control by feedback of at least one quantity obtained from a measurement signal.

[0065] In one possible embodiment of the present invention, the vibration damping comprises a control which is effected by feedback of at least one of the following quantities: speed and position of one or more of the joints, speeds and positions of the bending and / or torsion of one or more of the segments.

[0066] Preferably, the quantity(s) that are fed back by the control system are estimated by an observer. In particular, the observer described above can be used for this purpose.

[0067] In one possible embodiment of the present invention, the system state is estimated and / or the vibration damping and / or the influence of disturbance forces on the articulated arm is determined based on a linearization of a physical model, and in particular on a linearization of the physical model as described above. Specifically, the estimation is performed by an observer and / or the control and / or the disturbance feedforward, as described above, based on a linearization.

[0068] Preferably, the linearization is performed around the equilibrium position of the current position of the articulated arm. The linearization can be carried out by the control system depending on the current position of the articulated arm.

[0069] In one possible embodiment of the present invention, the control system comprises a feedforward control which calculates control signals from a setpoint specified by an operator, by which the desired mast movement is carried out and vibration excitation of the articulated arm is reduced.

[0070] Preferably, the feedforward control is designed to suppress the natural frequencies of the articulated arm. The natural frequencies of the articulated arm, which are taken into account by the feedforward control, can be determined as a function of the current position of the articulated arm.

[0071] In one possible embodiment of the present invention, the control system comprises axis controllers assigned to the respective joints, wherein the control system generates control signals for the target angular velocity of the axes, on the basis of which the axis controller assigned to the respective joint generates control signals for the respective actuator, wherein the axis controllers preferably are based on an inverse deflection kinematics and / or comprise an inverse nonlinearity.

[0072] In one possible embodiment of the present invention, the articulated arm comprises a swivel base rotatable about a vertical axis and at least two segments pivotable about horizontal axes by means of joints, wherein the swivel base is movable about the vertical axis via an actuator and the segments are pivotable about the horizontal axes via actuators. More preferably, the articulated arm comprises at least three and more preferably at least four segments. Preferably, the control system, and in particular the disturbance feedforward and / or vibration damping, controls all actuators of the segments and / or the swivel base.

[0073] In one possible embodiment of the present invention, at least vertical vibration damping and / or disturbance feedforward is implemented. For this purpose, the vibration damping and / or disturbance feedforward controls the actuators by which the segments of the articulated arm are rotated about their horizontal axes of rotation.

[0074] In one possible embodiment of the present invention, at least horizontal vibration damping and / or disturbance feedforward is implemented. For this purpose, the vibration damping and / or disturbance feedforward controls the actuator of the swivel block accordingly.

[0075] The actuators are preferably hydraulic actuators. The hydraulic actuators are preferably driven by a hydraulic pump, which is driven by the drive motor of the concrete pump.

[0076] Hydraulic cylinders are preferably used as actuators for pivoting the segments.

[0077] A hydraulic motor is preferably used as the actuator for rotating the turntable.

[0078] Preferably, the segments of the articulated arm can be folded into a transport position via the joints, with the individual segments preferably running essentially parallel in the transport position.

[0079] In one possible embodiment of the present invention, the control system comprises a geometry control system which, based on user specifications, preferably via hand levers, and / or based on a predetermined trajectory of the mast tip, which is preferably generated automatically, controls the actuators of the joints of the articulated arm to generate a corresponding movement of the mast tip.

[0080] The present invention further comprises a control unit for a concrete pump as described above. The control unit preferably operates as described above.

[0081] The control system preferably comprises a microprocessor and a memory in which control software is stored. When executed by the microprocessor, this software implements the structure and / or functionality of the control system according to the invention as described above. The control system further comprises one or more inputs through which it communicates with sensors, in particular the sensors described above, and / or one or more outputs through which it controls the actuators described above.

[0082] The disturbance variable feedforward and / or vibration damping according to the invention is preferably carried out automatically by the control of the concrete pump.

[0083] The present invention further comprises control software for a concrete pump as described above. The control software implements the control system according to the invention. The control software can be stored in memory and / or be a computer program.

[0084] In particular, the concrete pump according to the invention is a truck-mounted concrete pump. The concrete pump preferably comprises a chassis on which it can be moved. The chassis preferably comprises several wheeled axles.

[0085] The present invention further comprises a method for controlling a concrete pump as described above. According to the invention, the disturbance feedforward mechanism estimates the disturbance forces via a disturbance observer from measured values ​​of the position and / or vibration state of the placing boom and is based on a modal model that describes the vibration mode of the disturbance forces, wherein the modal model consists of a fundamental frequency and one or more multiples of the fundamental frequency, with the pumping frequency of the feed pump being included as the fundamental frequency in the modal model.

[0086] The method according to the invention is preferably carried out as described above.

[0087] The present invention will now be described in more detail with reference to exemplary embodiments and drawings.

[0088] This shows: Fig. 1 an embodiment of a large manipulator and a truck-mounted concrete pump according to the invention, Fig. 2 a schematic representation of an embodiment of a control system according to the invention with vibration damping and disturbance feedforward, Fig. 3 a schematic representation of a feedforward control system as it can be used in a control system according to the invention, Fig. 4 a schematic representation of an embodiment of a control system according to the invention with vibration damping, Fig. 5 a schematic representation of an axis controller as it can be used in a control system according to the invention, Fig. 6 a schematic representation of the disturbance forces acting on the articulated arm due to the concrete conveying, Fig. 7 a schematic representation of an embodiment of a control system according to the invention with disturbance feedforward, Fig.Fig. 8 A schematic representation of a further embodiment of a control system according to the invention with a disturbance variable feedforward, which is based on a physical model of concrete conveying. Fig. 9 A schematic representation of a further embodiment of a control system according to the invention with a disturbance variable feedforward, which is based on an estimation of the disturbance forces from measured values ​​of the position and / or the vibration state of the distributor mast. 0. Introduction

[0089] New design methods, materials, and electronic systems have led to the continuous development of concrete pumps over the past few decades. The use of multi-section articulated arms with increasingly longer segments allows for improved access to hard-to-reach areas. However, the increased number and length of the segments also increases the weight and dimensions of the vehicle. This results in limitations in road travel, handling, and the overall functionality of the concrete pump.

[0090] A particular phenomenon of large manipulators is the vibration tendency of the placing boom. These vibrations make it difficult for the operator to control the boom and for the end hose operator to distribute the concrete. This vibration tendency is linked to the slenderness and inertia of the segments and the elastic properties of the material.

[0091] The vibration excitation is caused by the articulated boom and the concrete pumping process. The typically used double-piston pump transmits impulse-like disturbances to the placing boom, thus causing continuous vibration excitation. Depending on the boom position and pumping frequency, excitation close to the boom's natural frequencies is also possible.

[0092] The combination of travel and concrete delivery subjects the placing boom to continuous vibration during normal operation. This affects the machine's service life and operator safety.

[0093] The aim of the present invention is to dampen vibrations of the distributor mast in order to improve the handling and functionality of the concrete pump. 1. State of the art

[0094] EP 2 103 760 B1 (Cifa) proposes a model-based vibration damping system using a modal model. The control algorithm estimates the system's state using an observer and feeds the estimated signal back via control gains. These gains are retrieved from a list and interpolated depending on the mast position. The method is based on a modal model obtained through modal transformation and subsequent model reduction to the first vibration modes. The individual states of the model are thus modal coordinates and have no physical interpretation. A disadvantage of this method is that, in addition to the control gains, the reduced modal model of the observer is also dependent on the current mast position. Therefore, the modal model must be regenerated for each mast position or is only valid for specific mast positions.Due to the large number of possible mast positions, this limits the applicability of vibration damping. The vibration damping method proposed below circumvents these problems through a different type of modeling. The model reduction is physically motivated and leads to physically interpretable, elastic coordinates. Furthermore, the sensor combination used for vibration damping differs.

[0095] WO 2014165889 A1 (TTControl) presents a vibration damping system based on the feedback of position and deformation signals from the mast segments. The position is measured using an inertial measuring unit, and the deformation is measured using strain gauges. The inertial measuring unit comprises a gyroscope and an accelerometer, which are used only in combination for position estimation (see claim 2). The method has the advantage that the vibration of the segments is detected independently of the traversing motion. This eliminates the need for additional signal processing to separate the traversing motion from superimposed structural vibration. However, the use of strain gauges has the disadvantage that installation is complex and must take place at highly stressed points on the segment. Furthermore, the sensor is very temperature-sensitive and requires extensive calibration.The vibration damping proposed below avoids these disadvantages by using a rotation rate sensor to detect vibrations in the distribution mast.

[0096] WO 2016 131977 A1 (Schwing) uses inertial measurement units for position control of the mast tip. The measurement units are mounted on the segments, each in the center of the beam. An additional sensor is located at the mast tip. The acceleration and rotation rate signals from the sensors are fused using a rigid body approach to estimate the position of the mast tip. To improve the position estimation, the acceleration signal from the sensor at the mast tip is integrated twice and fused with the existing estimate. An absolute position determination is not possible due to the rigid body approach and the double integration. Instead, the dynamic components of the mast tip position are calculated using a high-pass filter and fed back via a PID controller. An underlying position control at the joint level prevents drift effects of the mast tip. The fusion algorithm is solely responsible for reconstructing the position of the mast tip.Due to the positioning of the inertial measurement units and the rigid body approach used, only the inclination of the segments is estimated, not the vibration state of the distribution mast. This differs from the model-based approach for estimating and controlling the vibration state of the distribution mast presented below. This approach considers the vibration state of the entire mast. In contrast to position control of the mast tip, this allows the number of sensors used to be reduced and limited to the use of gyroscopes.

[0097] EP 1 537 282 B1 (Putzmeister) proposes geodetic angle sensors for position determination and vibration damping of the placing boom. The sensors are mounted on the segments and provide the respective absolute inclination. Taking the kinematics into account, the signals are split into a low-frequency component for coordinate control and a high-frequency component for vibration damping. The tilt sensors typically used are sensitive to translational acceleration peaks. Their application for vibration damping, considering travel and concrete delivery, is therefore severely limited.

[0098] EP 2 778 466 A1 presents a vibration damping system in the horizontal plane.

[0099] EP 1 122 380 B1 (Putzmeister) proposes a control device for the periodic variation or modulation of the pump frequency. This variation or modulation prevents excitation frequencies from occurring near the natural frequency of the mast. The result is reduced vibration excitation of the placing mast. The method modifies the concrete delivery to dampen the vibrations in the placing mast. This differs from the disturbance feedforward described below, which utilizes the placing mast's actuators and leaves the concrete delivery unaffected.

[0100] EP 1 537 282 B1 (Putzmeister) describes a disturbance variable controller for reducing vibrations in a distribution mast. However, the method is not a disturbance variable feedforward, as it uses a measured value from the distribution mast, rather than a disturbance variable, for vibration damping. This measured value is the dynamic component of the mast's position detection. It is amplified by a controller and fed back to the mast's actuators. Therefore, the method represents a classic, feedback-based vibration damping system, not a disturbance variable feedforward.

[0101] DE 101 01 570 B4 (Vibration) describes a disturbance variable feedforward combined with feedback-based vibration damping based on the principle of a virtual spring-damper element. The measured disturbance variable depends on the concrete delivery; however, there is no explicit, model-based conversion into the disturbance forces on the placing boom. Furthermore, the presented method is implemented decentrally for each joint. The influence of the disturbance forces on the entire placing boom is therefore not considered. The proposed sensor system for measuring the pressure of the concrete flow in the delivery line is practically unusable because it is expensive and subject to significant wear during operation. 2. Construction of the exemplary embodiment in the form of a truck-mounted concrete pump

[0102] In Fig. 1The relevant elements of the truck-mounted concrete pump are shown. It has an undercarriage with a chassis featuring multiple wheeled axles, enabling the truck-mounted concrete pump to travel on roads. Front and rear outrigger cylinders 9 and 10 are provided on the undercarriage, which are arranged on fold-out and / or telescopic struts 10 and 12. A distribution gearbox 11 is also shown.

[0103] The undercarriage carries a pump group 1 at the rear and, via a mast block 2, an articulated arm along which a conveying line (not shown) is routed.

[0104] The articulated arm consists of a swivel base 3 and four segments 4 to 7 (any number of segments is possible), which are coupled via joints A to E. Joint A on the vehicle allows the swivel base 3 to rotate about its vertical axis, while joints B to E allow the segments 4 to 7 to pivot about their horizontal axes. The concrete pump's actuators consist of hydraulic cylinders 14 to 17 at the respective joints B to E and a hydraulic motor for the swivel joint A of the swivel base. The hydraulic cylinders 14 to 17 enable the movement of the placing boom in the vertical plane. The hydraulic motor rotates the entire boom about its vertical axis. The boom tip 22 (TCP) is the top of the placing boom.

[0105] A delivery line is attached to the distributor mast, which transports concrete to the mast tip 22. From there, the concrete is conveyed via a hose section 8 to an operator. The required delivery pressure is generated by a double-piston pump of pump unit 1.

[0106] The planned vibration damping system is divided into the following sections: Fig. 2 The subsystems shown are: geometry control, feedforward control, control (with observer) and disturbance feedforward.

[0107] For each subsystem, the structure and function are discussed below, and characteristic features are presented. 3. Geometry control (TCP control)

[0108] The geometry control system generates motion paths for the distribution mast. These motion paths are time-functions of the position, velocity, acceleration, and / or jerk of the distribution mast's pivot axes. They are adapted to the system's dynamics in the feedforward control and specified as setpoints for the control system. 4. Feedforward control 4.1 Function

[0109] The pre-control according to Fig. 3 It serves to enable a fast distribution mast procedure without exciting the natural frequencies. Measurement of the distribution mast's position. Determination of the (first) natural frequencies and damping of the distribution mast in the respective mast position (rest position) in the horizontal and vertical planes. Filtering of the setpoint signals with natural frequencies (notch filter, input shaping). Feedforward control acts on each vertical and horizontal actuator. 4.2 Sensors

[0110] Position of the distribution mast; rotary encoder for the rotation angle around the vertical axis 4.3 Actuators

[0111] Hydraulic cylinder (vertical plane) Hydraulic motor (horizontal plane) 5. Regulation

[0112] The regulation which is in Fig. 4 which is reproduced again, is subdivided into two parts: the axle control ( Fig. 5 ) and the control system for damping the vibrations and position control with the controller and the observer. 5.1 Axle controller

[0113] The axle controller according to Fig. 5It serves to convert the target angular velocity of the joint into the actual actuator velocity: The transmission behavior of the hydraulic system, from control input to actuator speed, exhibits nonlinear characteristics. The axis control compensates for the nonlinearities of the hydraulics and the deflection kinematics. The control algorithm consists of the inverted static characteristics of the hydraulics and the deflection kinematics. Feedback of pressure, cylinder position, or speed may be provided. The axis control is implemented decentrally at each joint and represents the lowest level of the overall vibration damping system.

[0114] In its function of converting the target speed into the actual actuator speed, axis control is implicitly assumed for all further control concepts. 5.2 Vibration damping based on gyroscopes 5.2.1 Vibration Damping Structure

[0115] The process incorporates active vibration damping to reduce vibrations in the placing boom. It distinguishes between the intended movements of the segments by the operator and the vibrations induced by the movement itself. The vibration damping takes the intended movement into account and only dampens the resulting structural vibrations. Vibrations caused by the concrete conveying process are also reduced.

[0116] The goal of vibration damping is to reduce vibrations throughout the entire distribution mast. To achieve this, the vibration state of the entire arm is estimated from the vibrations of the individual segments. The distribution mast exhibits variable natural frequencies depending on the position and inclination of the segments. Vibration damping takes this variability of natural frequencies into account as a function of the mast's position. The first natural frequencies have the greatest influence on the vibration behavior. 5.2.2 Sensors

[0117] The vibration state of the distribution mast is detected by gyroscopes 18 to 21. These sensors are mounted on one or more segments 4 to 7 and measure the rotation rate around the joint axes. The advantage of these vibration sensors lies in their ease of installation compared to conventional sensors (e.g., strain gauges). The sensor can be mounted on any external or internal surface of the segment. Furthermore, these MEMS-based gyroscopes are cost-effective, robust, and require minimal maintenance.

[0118] The gyroscope 18 to 21 is mounted in the front area of ​​each segment 4 to 7 to optimally detect structural vibrations. Due to the serial kinematics of the manipulator, the measured gyroscope rate of one segment also includes the vibration of the preceding segment. This fact will be taken into account in the control design.

[0119] The position of the distribution mast is determined by a direct or indirect measurement of the relative joint angles between the segments. For example, the relative joint angles can be measured using rotary encoders. 5.3.3 Modeling

[0120] The control design is based on a mathematical model of the distribution mast. For this purpose, the mechanical system is represented by a dynamic model.

[0121] The distribution mast is modeled using a rigid body model with actuated joints B to E. Additional virtual joints account for the flexibility in the segments. For each segment, an additional virtual joint with spring and damping elements is introduced. The spring and damping constants are chosen to preserve the deflection and the first natural frequency of the real segment. The distribution mast model consists of several segments. The stiffness of the overall structure is therefore derived from the stiffness of the individual segments. Since the overall structure is composed of multiple segments, higher natural frequencies are also represented.

[0122] This type of modeling represents a physically motivated discretization of the infinite-dimensional, elastic distribution mast. The advantage is that well-developed and efficient rigid body formalisms can be used for the modeling. The resulting model also exhibits a relatively low system order. Unlike in a modal model reduction, the system state of the virtual joints remains a physical variable. It describes the concentrated deflection and vibration of the segment.

[0123] The nonlinear model of the distribution mast is linearized around the equilibrium position of the current mast position. This results in a linear system, depending on the mast's position and load, which represents small deviations from the equilibrium position. x ˙ = Ax + Bu , y = Cx . 5.3.4 Observer

[0124] Based on the linearized model, an observer is used to estimate the system states. x ^ ˙ = A x ^ + Bu + L y − C x ^ .

[0125] The observer reconstructs the system state using the system's inputs and outputs. x̂ . The system's inputs u These are the setpoint values ​​of the hydraulics. The outputs y These are the measured values ​​of the position and vibration state of the distribution mast. By fusing the various measurement signals, the robustness of the vibration damping is improved with respect to the drift phenomena inherent in the measurement principle of the gyroscope. The model-based observer also ensures that the measurement signal from the gyroscopes is separated into the individual components of the joint movement and the vibration. The control system thus selectively dampens the structural vibrations without affecting the target movement. The observer gain L is selected by a suitable method such as polarity preselection or by a Kalman filter. 5.3.5 Rule Reinforcement

[0126] The linearized model is used to design the feedback gains. K of the control loop u = K x ^ .

[0127] The poles in the complex half-plane are positioned to increase the system's damping. This dampens the vibrations in the distribution mast. The controller receives the observer's estimated state. x̂ , amplifies the signals and feeds them as setpoints to the hydraulics (see Fig. 4 ). The rule reinforcement K is calculated using a suitable method such as pole specification or optimization-based methods (LQR).

[0128] The design process for observers and controllers described above applies to a specific equilibrium position of the distribution mast. Therefore, if the mast position changes, the design process is repeated and adapted to the current position. By adjusting the control parameters, the functionality of the vibration damping is ensured for every mast position.

[0129] The cyclic design of the observer and controller results in gains that depend on the current position and load of the distribution mast. The mast's variable natural frequency is thus implicitly considered in the control design. 5.3.6 Horizontal vibration damping

[0130] Vibration damping can also be used for vibrations in the horizontal plane. The hydraulic motor on the mast support serves as the actuator. The mast position around the vertical axis is detected by an angle sensor. In this case, the rotation angle sensors for vibration measurement are designed or extended to include detection in the horizontal plane and torsion. The sensors are mounted on one or more segments and measure the rotation rate around the vertical and longitudinal axes.

[0131] In the horizontal plane, horizontal bending is coupled with the torsion of the segments. The distribution mast thus experiences both horizontal bending and torsion simultaneously, depending on its position. This effector is taken into account in the modeling.

[0132] The dynamic model of the distribution mast (Section 5.3.3) is extended to include a horizontal component. The virtual joints in the segments are designed as multi-axis rotary joints that capture bending in the horizontal plane and torsion. Rotation about the vertical axis is accounted for by a joint at the swivel base. The type and structure of the model remain unchanged from Section 5.3.3.

[0133] Analogous to the procedure in sections 5.3.3, 5.3.4, and 5.3.5, an observer and a feedback gain are designed for the linearized extended model. Either separate horizontal vibration damping or combined vertical and horizontal vibration damping can be implemented. The model-based observer ensures that the measurement signal from the gyroscopes is separated into the components of the vertical axis motion and the vibration. The control system thus selectively dampens the structural vibrations of horizontal bending and torsion without affecting the desired motion. 5.3.7 Other properties

[0134] The operator's movement instructions are explicitly taken into account by the vibration damping. This means that the desired travel movement is permitted by the control system, and only the superimposed structural vibrations are damped. To further reduce vibration excitation during travel, a feedforward control system is also provided. This system calculates control signals from the operator's setpoint, which execute the desired mast movement without exciting any vibration. For this purpose, a notch filter is used, which suppresses the natural frequencies of the distribution mast during travel, depending on the current mast position (see [reference]). Fig. 3 ).

[0135] The setpoint signals for the hydraulics are converted at the cylinders by a subordinate axis control system. This system converts a target angular velocity u of the joints into the actual translational velocity of the cylinders. The deflection kinematics and nonlinearities of the hydraulics are taken into account by means of feedforward control (see Fig. 5 The feedback measurement can be either pressure, cylinder position, or cylinder velocity. Alternatively, the cylinder velocity can be calculated from the position via separate signal processing. The cylinders transmit the force. F u on the distribution mast, thus generating movement of the joints. The axis control, as described above, is decentralized and separately subordinate to each joint. 6. Disturbance feedforward

[0136] Traditionally, feedback-based vibration damping is used to reduce vibrations in the placing boom. These controls are based on feeding back the static and dynamic parameters of the placing boom. For this purpose, the vibrations in the structure are measured, processed with a control algorithm, and fed back as a control signal to the actuators of the concrete pump. The resulting movement of the actuators acts on the placing boom and actively dampens vibrations. A disadvantage of this method is that vibrations can only be compensated when they are measured at the boom. This means that the vibrations must first occur in the structure in order to be dampened. The method described below follows a different approach based on the principle of disturbance feedforward. This dampens vibrations in the system based on the cause instead of – as with feedback-based methods – based on the effect (see Fig. 7The vibration excitation in the distribution mast is largely attributable to the concrete conveying process. It therefore represents a disturbance in the system that needs to be compensated for.

[0137] The advantage of disturbance feedforward compared to traditional vibration damping is that disturbances can be compensated for before they affect the system. This means that the excitation of the concrete pumping process is eliminated before it becomes visible as vibration in the placing boom.

[0138] The goal of disturbance variable feedback is therefore to reduce vibrations in the placing boom based on characteristic measurements of the concrete pumping process. These measurements describe the state of the concrete pumping process and not the vibration state of the placing boom itself. Typical measurements of concrete pumping include the pressure at the inlet of the pumping line, the frequency of the pumping process, and the position and speed of the pumping piston.

[0139] Using the measured values, the disruptive forces on the placing boom are reconstructed via a model of the concrete conveying process and amplified before being applied to the actuators. The amplification can be designed to eliminate the influence of these disruptive forces on a specific point of the placing boom. The boom tip is chosen for this purpose, ensuring a stable and constant position of the end hose.

[0140] To reduce vibrations caused by concrete pumping, two methods are proposed: the classic model-based disturbance feedforward and the disturbance feedforward with a disturbance observer. 6.1 Classical model-based disturbance feedforward 6.1.1 Overview 6.1.1.2 Function

[0141] The calculation of the in Fig. 6 The depicted disruptive forces are calculated using a mathematical model of concrete delivery along the mast. Calculation of the disturbance forces on the distributor mast from measurement signals of the concrete delivery (pressure, frequency, cylinder position) via concrete delivery model (see F Fig. 8). Calculation of the influence of the disturbance forces on the distribution mast in the disturbance model. State control of the disturbance model. The manipulated variable u d The manipulated variable of the controlled disturbance model is u The hydraulics of the concrete pump. The state control can be extended by an output feedback loop. This dampens the movements of the boom tip. The operating point is the current position of the placing boom. If the boom position changes due to a travel movement, the operating point is adjusted accordingly. That is, the height of the boom tip after the movement represents the new operating point. Deviations from the setpoint y d (see Fig. 8 ) are controlled via a feedback loop using the actual measured values ​​of the concrete pump y compensated. This control loop can represent the vibration damping from section 5.2. 6.1.1.2 Notes

[0142] The additional control loop of the disturbance model enables compensation of the disturbance variables. F d independent of the external control for vibration damping (measurement signal) y ). Since the state controller applies a virtual disturbance model, the complete state x d available. Constraints on the manipulated variable can be easily addressed by constraints in the feedforward control loop. 6.1.1.3 Sensors

[0143] Position of the distributor mast. Measured values ​​for concrete delivery: amplitude or cylinder position, cylinder speed, pump frequency and / or concrete pressure at the inlet of the delivery line. 6.1.1.3 Actuators

[0144] All hydraulic cylinders (vertical plane) 6.1.2 Example of implementation 6.1.2.1 Modeling

[0145] The concrete delivery model depicts the concrete flow in the delivery line from the delivery pump in the vehicle to the end hose at the top of the boom. The flow-related disturbance forces acting on the placing boom are calculated.

[0146] The generation of these disruptive forces is primarily due to frictional forces on the inner pipe wall and inertial forces caused by the deflection of the concrete flow in the pipe bends. The unsteady, periodic conveying process generates impulse-like forces that are transmitted to the placing boom via the pipe supports. These forces depend on a multitude of factors. The most significant influences are the rheological properties and composition of the concrete. Depending on the type and consistency of the concrete, considerably different vibration excitations occur in the placing boom. Another factor is the so-called wall effect. Due to the viscosity and inhomogeneous composition of the fluid, a boundary layer with a low yield point and viscosity forms in the wall region during conveying. This boundary layer acts like a lubricating film and reduces the frictional forces in the wall region.Other factors include the variable level factor in the conveying piston and the amount of dissolved air in the concrete. The uncertainty and variability of the aforementioned factors make direct, purely material-based modeling extremely difficult. Therefore, a measurement-based model is proposed. The fundamental idea is to forgo precisely mapping the flow conditions within the pipe and instead consider only the forces acting on the pipe wall.

[0147] The approach uses an equivalent Newtonian fluid to model the frictional and inertial forces of the fluid on the pipe wall.

[0148] The material properties of the equivalent fluid are determined from the measured parameters of the concrete delivery. In particular, at least the viscosity of the equivalent fluid is determined from the concrete pressure and the flow velocity of the concrete. A stored average value for the density of concrete is used as the density of the equivalent fluid.

[0149] Assuming ambient pressure at the end hose and measuring the inlet pressure, the pressure difference across the entire pipeline can be calculated. By considering the mast position, the hydrostatic pressure loss of the flow is also determined. The output variables of the model are the concentrated disturbance forces. F d in each joint of the concrete pump (see Fig. 6 ).

[0150] The effect of concentrated disruptive forces F d The calculation is performed via a coupling with a mechanical model of the distribution mast. The mechanical model takes into account the dynamic and elastic deformation of the segments under the influence of disturbance forces across the entire distribution mast. 6.1.2.2 Activation

[0151] The coupled model of concrete pumping and distribution mast serves as the basis for designing a model-based dynamic disturbance feedforward. The model is extended to include a control loop for reducing disturbances in the distribution mast (see disturbance model control loop in [reference]). Fig. 8 Unlike classical feedback control, only the "virtual" model is controlled, not the actual path. This offers advantages for control design, as path uncertainties and disturbances do not occur. Furthermore, the entire state vector is available without the need for an observer. The control system is designed to minimize the influence of disturbance forces on the mast tip.

[0152] To compensate for the disturbances in the real system, the manipulated variable of the virtual control loop is now used. u d The actuators are connected to the system. This results in a feedforward control that does not require feedback on the dynamic state of the distribution mast. 6.1.2.3 Regulation

[0153] The disturbance feedforward is combined with traditional vibration damping to compensate for vibrations from the mast's movement and uncertainties in the modeling. The vibration damping is based on measuring and feeding back the position and vibration state of the distribution mast. This is achieved by considering the virtual outputs. yd and the measured variables y The control system is designed so that the manipulated variables of the disturbance feedforward are and The vibration damping acts unhindered on the track. It only engages when the states of the real track deviate from the states of the virtual model. 6.1.2.4 Other properties

[0154] Alternatively, the hydraulic pressure of the conveying cylinders can be measured to determine the concrete pressure at the entrance of the track. The corresponding concrete pressure is then calculated using the piston area ratio.

[0155] Furthermore, the flow rate of the concrete can also be determined from the speed of the conveying cylinders.

[0156] This avoids the use of an expensive and wear-prone pressure sensor and / or flow sensor in the delivery line.

[0157] The performance of the disturbance feedforward described above is highly dependent on the accuracy of the concrete conveying and mechanical models. This leads to performance limitations in cases of parameter uncertainty and variability. 6.2 Asymptotic interference compensation 6.2.1 Overview 6.2.1.1 Function

[0158] Estimation of the disturbance variable , according to the invention, from the vibration measurements of the distribution mast and the pumping frequency of the concrete delivery (see Fig. 9The disturbance signal is amplified in the disturbance controller and applied to the actuator of the concrete pump. For stability reasons, the disturbance compensation requires vibration damping, which can be implemented, for example, as described in Section 5.2. Compared to classical disturbance feedforward, the disturbance observer has the advantage that the disturbance signal is estimated entirely from the existing vibration damping sensors. This makes the method robust against parameter changes in the concrete pumping process. The estimation algorithm can, for example, be implemented as asymptotic disturbance compensation according to Davison. The disturbance compensation is based on the use of a freely selectable measurement output. y d The disturbance variable is estimated / learned. The goal is to adjust this measurement output using suitable control variables. yd to regulate to a constant value. One possible choice of measurement output. yd The height of the mast tip in the vertical plane is called the operating point. The disturbance compensation reduces vibrations at the mast tip. The operating point is the current position of the distribution mast. When the mast position changes due to travel, the operating point is adjusted accordingly. This means that the height of the mast tip after this adjustment represents the new operating point. 6.2.1.2 Sensors

[0159] Position of the distributor mast, pumping frequency of the concrete delivery, measurement of the vibration state of the distributor mast: rotation rate sensors on specific segments 6.2.1.3 Actuators

[0160] All hydraulic cylinders (vertical plane) 6.2.1.2 Notes

[0161] Asymptotic disturbance compensation is based on representing incoming disturbance signals with a fictitious disturbance model. This model is integrated into the control loop and driven by a selected measurement output until the disturbances are compensated at that output. The disturbance model has the property of providing a non-zero output signal even when the excitation signal vanishes (limit stability). This allows the disturbance compensation to generate the necessary manipulated variables to counteract the effects of the disturbance. Due to the estimation process, the disturbances affect the system outputs, at least temporarily. This results in the disturbance compensation exhibiting a transient response at the beginning and during large parameter changes. 6.2.2 Example of Implementation 6.2.2.1 Modeling

[0162] The following presents an alternative method, according to the invention, to the disturbance feedforward method described above. The fundamental idea of ​​the method is to estimate the disturbance forces from the measured values ​​of the distribution mast. The periodicity of the concrete delivery is used to establish a modal model of the disturbance forces. This model consists of the fundamental frequency and its multiples. The individual states, as modal coordinates, represent the vibration mode of the disturbance. A modal coordinate has no physical meaning but merely indicates the contribution of the respective frequency to the vibration mode of the disturbance. 6.2.2.2 Estimation methods

[0163] Based on the modal model, the disturbance forces are estimated from the distribution mast's measurements by a disturbance observer or an asymptotic disturbance compensation system. The estimation methods are based on the internal model principle. This principle defines that a stable control loop can only completely suppress a disturbance if it possesses an internal model of the disturbance signal. This model is limit-stable and consists solely of conjugate complex pole pairs of the feeder frequencies on the imaginary axis of the complex half-plane. The disturbance observer or the asymptotic disturbance compensation system adapts the initial state of the modal model from the distribution mast's measurement signals. This corresponds to an estimation of the unknown amplitude and phase of the disturbance forces. The more frequencies the model contains, the more accurately the oscillation mode of the disturbance can be represented.However, a larger number of frequencies requires more time to learn the given oscillation pattern. During the learning process, a transient response occurs, the amplitude of which increases with the number of frequencies. For effective noise suppression, the number of frequencies must therefore be chosen so that, on the one hand, the noise is represented with sufficient accuracy, and on the other hand, the transient response is short and has a low amplitude. 6.2.2.3 Regulation

[0164] The reconstructed disturbances are applied to the actuators of the distribution mast via a control system (see Fig. 9The disturbance feedforward is combined with vibration damping based on the measured variables of the distribution mast y to ensure system stability. The system states are estimated by the disturbance observer based on the distribution mast model and the disturbance model. The measured variables include the mast position and the vibration state of the distribution mast. The controller in Fig. 9 This amplifies the estimated disturbances and system states. The disturbance feedforward can be designed to minimize the influence of the disturbance forces on the mast tip. 6.2.2.4 Other properties

[0165] Unlike the first method, the disturbance observer or the asymptotic disturbance compensation learns the disturbance forces from the measured values. y of the dynamic vibration state of the placing boom. This allows for a reduction in the number of sensors required for concrete delivery. The necessary measurement parameter is the pump frequency, which can be determined in the software via the switching points of the delivery cylinders. A further advantage of the method is its robustness to changes in pipeline parameters and variations in concrete properties. 6.3 Further properties of the disturbance feedforward

[0166] The disturbance feedforwards described above apply to a specific equilibrium position of the distribution mast. Therefore, if the mast position changes, the design process is repeated and adapted to the current position. By adjusting the control parameters, the functionality of the disturbance feedforwards is ensured for every mast position.

[0167] The setpoint signals for the hydraulics are converted at the cylinders by a subordinate axis control system. This system transforms a target angular velocity of the joints into the actual translational velocity of the cylinders. The deflection kinematics and nonlinearities of the hydraulics are taken into account through feedforward control. Depending on the design, feedback of pressure, cylinder position, or velocity can be implemented. The axis control system is decentralized, meaning it is implemented separately for each joint.

[0168] The operator's movement instructions are explicitly taken into account through disturbance feedforward and vibration damping. This means that the desired movement is permitted by the control system, and only the superimposed structural vibrations are dampened. To further reduce vibration excitation during operation, feedforward control is also provided. This calculates control signals from the operator's setpoint. ω should , which execute the desired mast movement without exciting any vibration. For this purpose, a notch filter is used, which suppresses the natural frequencies of the distribution mast during the travel movement, depending on the current mast position.

[0169] The feedforward control is used for the presented disturbance feedforwards in the Fig. 8 and 9 characterized by a signal block. ω shouldAdditional factors are taken into account in the disturbance model control loop.

Claims

1. Concrete pump, in particular truck-mounted concrete pump, comprising a delivery pump, a concrete line and an articulated arm forming a distribution boom, along which the concrete line is guided, wherein the articulated arm has a slewing pedestal (3) rotatable about a vertical axis (A) and / or at least one segment (4 - 7) pivotable by means of a joint (B - E) about a horizontal axis, wherein the slewing pedestal (3) is movable about the vertical axis (A) via an actuator and / or the at least one segment (4 - 7) is pivotable about the horizontal axis via an actuator (14 - 17), wherein the concrete pump furthermore has a control system for actuating the actuators (14 - 17) of the distribution boom, wherein the control system comprises a disturbance feedforward control for reducing the vibrations of the distribution boom induced by the concrete delivery, characterized in that the disturbance feedforward control estimates the disturbance forces via a disturbance observer from measured values of the position and / or of the vibration state of the distribution boom, wherein the disturbance feedforward control is based on a modal model which describes the vibration form of the disturbance forces, wherein the modal model is composed of a fundamental frequency and one or more multiples of the fundamental frequency, wherein the pumping frequency of the delivery pump (1) enters into the modal model as the fundamental frequency.

2. Concrete pump according to claim 1, wherein the disturbance feedforward control determines the initial state of the modal model from the measured values of the position and / or of the vibration state of the distribution boom, in particular via an observer which estimates the vibration state generated by the disturbance forces, in particular by estimating the phase position and amplitude of the modes of the modal model.

3. Concrete pump according to any one of the preceding claims, wherein the disturbance feedforward control is furthermore carried out on the basis of a physical model of the distribution boom, by means of which the influence of the disturbance forces on the vibration state of the distribution boom is described, wherein the physical model of the distribution boom preferably takes into account the elastic deformation of at least one of the segments (4 - 7).

4. Concrete pump according to any one of the preceding claims, wherein the disturbance feedforward control actuates the actuators (14 - 17) of the distribution boom on the basis of the estimated disturbance forces.

5. Concrete pump according to any one of the preceding claims, wherein the disturbance feedforward control actuates the actuators (14 - 17) such that the influence of the disturbance forces on a point of the distribution boom, in particular on the tip (22) of the distribution boom, is reduced and preferably eliminated.

6. Concrete pump according to any one of the preceding claims, wherein the control system estimates the system state on the basis of a modal model of the disturbance forces and a physical model of the distribution boom.

7. Concrete pump according to any one of the preceding claims, wherein at least one operating parameter of the delivery pump (1) and / or concrete delivery enters into the disturbance feedforward control, wherein the disturbance feedforward control preferably determines the pumping frequency of the delivery pump from the actuation parameters and / or actuation signals for the delivery pump (1).

8. Concrete pump according to any one of the preceding claims, wherein the control system, in addition to the disturbance feedforward control, furthermore comprises a closed-loop control which is based on a measurement and / or feedback of the position and / or of the vibration state of the distribution boom, wherein the closed-loop control preferably comprises a vibration damping for damping horizontal and / or vertical vibrations of the distribution boom.

9. Concrete pump according to claim 8, wherein the vibration damping is based on the same physical model of the distribution boom which also serves for determining the influence of the disturbance forces of the concrete delivery on the distribution boom.

10. Concrete pump according to any one of the preceding claims, comprising at least one rotation-rate sensor (18 - 21) which is arranged on a segment (4 - 7), wherein the control system for disturbance feedforward control and / or vibration damping, on the basis of the measured values of the rotation-rate sensor (18 - 21), determines a vibration state of the entire distribution boom from the vibrations of the individual segments (4 - 7) and / or is carried out without the use of geodetic sensors and / or at least one rotation-rate sensor is arranged in a front region of a segment (4 - 6) which is arranged in the articulated arm between the slewing pedestal (3) and a segment (7) forming the boom tip (22).

11. Concrete pump according to any one of the preceding claims, wherein the disturbance feedforward control and / or vibration damping is carried out using a physical model of the distribution boom, in which the flexibility of at least one segment (4 - 7) is described by a virtual joint arranged within this segment (4 - 7), wherein a spring element and a damping element are preferably assigned to the virtual joint, wherein the spring constant and the damping constant are more preferably selected such that the virtual joint describes the deflection, torsion and / or first natural frequency of the real segment (4 - 7).

12. Control system and / or control software for actuating the actuators (14 - 17) of a concrete pump according to any one of the preceding claims, wherein the control system and / or control software comprises a disturbance feedforward control having the features described in one of the preceding claims.

13. Method for actuating the actuators (14 - 17) of the distribution boom of a concrete pump according to any one of claims 1 - 11, wherein the disturbance feedforward control estimates, via a disturbance observer, the disturbance forces from measured values of the position and / or of the vibration state of the distribution boom and is based on a modal model which describes the vibration form of the disturbance forces, wherein the modal model is composed of a fundamental frequency and one or more multiples of the fundamental frequency, wherein the pumping frequency of the delivery pump (1) enters into the modal model as the fundamental frequency.