ES2969925T3 - concrete pumps - Google Patents

Abstract

The present invention shows a concrete pump, in particular a truck-mounted concrete pump, with a transport pump, a concrete conduit and an articulated arm forming a distributor arm, along which the concrete conduit is guided. , the articulated arm presenting a rotating support that can rotate around a vertical axis and/or at least one by means of a joint has a segment that can rotate about a horizontal axis, the rotating support being mobile around the vertical axis through an actuator and/or the at least one segment being pivotable about the horizontal axis through an actuator, the concrete pump further having a control to control the actuators of the distribution arm, wherein the control includes a variable disturbance feed to reduce the placing arm vibrations induced by concrete delivery. It is characterized because the disturbance variables are applied based on a physical concrete delivery model, which describes the disruptive forces related to the concrete delivery flow over the placement boom. (Automatic translation with Google Translate, without legal value)

Description

DESCRIPTION

concrete pumps

The present invention relates to a concrete pump with a feed pump, a concrete line and an articulated arm forming a distribution arm, along which the concrete line is guided, the articulated arm having a rotating support which can rotate about a vertical axis and/or at least one that can be rotated about a horizontal axis by means of a joint segment, wherein the rotating support can be moved around the vertical axis by means of an actuator and/or the at least one segment can rotated about the horizontal axis by an actuator, the concrete pump also having a control to control the actuators of the distribution arm, the control being a disturbance input to reduce vibrations of the placing arm induced by the concrete supply. In particular, the concrete pump is a truck-mounted concrete pump.

The relevant prior art is explained in detail in the introductory section of the description of the figures. In particular, DE 101 01570 B4 shows a disturbance variable supply combined with a feedback-based vibration damping according to the principle of a virtual spring damping element, by which a hydraulic cylinder of the articulated arm is to be described. The connection of the disturbing variable must be done using pressure or flow sensors in the supply line. To this end, the control device comprises a pressure measuring device in the concrete transport duct, where two pressure sensors are preferably provided distributed throughout the transport duct and which can determine pressure differences in the transport duct. For example, by measuring the delivery pressure at two measurement points, the occurrence of a pressure difference and the development of said pressure wave through the delivery line can be estimated.

Document JP 2000282687 A describes a concrete pump where the pumping frequency is changed to avoid excessive excitation of the vibrations of the placing arm.

The objective of the present invention is to provide a concrete pump with an improved variable disturbance feed.

This objective is achieved in a first aspect by a concrete pump according to claim 1 and in a second aspect by a concrete pump according to claim 9.

Preferred configurations of the present invention are the subject of the dependent claims.

In a first aspect according to claim 1, the present invention comprises a concrete pump with a feed pump, a concrete line and an articulated arm forming a distribution arm, along which the concrete line is guided, the articulated arm having a rotating platform that can rotate about a vertical axis and/or at least one means that a joint has a segment that can rotate about a horizontal axis, where the rotating support can move around the vertical axis through of an actuator and/or the at least one segment can rotate around the horizontal axis through an actuator, and wherein the concrete pump also has a control to control the actuators of the distribution arm, the control comprising a variable supply of disturbance to reduce distribution arm vibrations induced by concrete delivery. The first aspect is characterized in that the disturbing variables are applied on the basis of a physical model of the concrete supply, which describes the disturbing forces related to the flow of the concrete supply over the placing arm. The use of the physical model and the determination based on it of the disruptive forces on the placing boom result in a significantly improved reduction of vibrations induced by concrete transport.

In a first embodiment of the present invention, the physical model describes the friction forces of the concrete on the inner wall of the concrete pipe and/or the inertia forces due to the deviation of the concrete flow in the bends of the pipe. . These two forces essentially determine the disturbing forces acting on the articulated arm.

In a possible embodiment of the present invention, at least one operating parameter of the supply pump and/or the concrete supply is included in the disturbance preintervention. This may, for example, be one or more of the following operating parameters: concrete pressure, pumping frequency, speed of the supply pump cylinders and/or position of the supply pump cylinders.

In a possible embodiment of the present invention, the physical model of the concrete delivery takes into account the current position of the distribution boom and, in particular, the bend angles of the joints.

Preferably, the determination of the current position of the distributor boom is carried out on the basis of sensors associated with the rotary joints to indirectly or directly measure the respective rotation angle of the joints of the articulated arm.

Preferably, the determination of the disturbing forces of the concrete supply in the distribution boom is carried out without measurement of the vibration state of the distribution boom or the segments.

Preferably, the position of the spreading boom and, in particular, the bend angles of the joints are included in the description of the concrete flow deflection by the physical model. Alternatively or additionally, the physical model may take into account the hydrostatic pressure loss of the flow, taking into account the current position of the distributor boom.

In a possible embodiment of the present invention, at least one material property of the pumped fluid that is included in the modeling by the physical model is determined from operating parameters of the supply pump and/or the concrete supply. This can improve the accuracy of the model.

Preferably at least the viscosity of the pumped fluid is determined, in particular from the concrete pressure and the concrete flow rate.

The density of the pumped fluid can be determined from the static pressure of the concrete. Alternatively, for the density of the pumped fluid, on the other hand, a stored average value of the concrete density can be used.

In a possible embodiment of the present invention, the disturbance preintervention is further based on a physical model of the distribution boom that is coupled to the physical model of the concrete pumping to determine the influence of the disturbance forces determined by the physical model. of concrete pumping throughout the distribution boom.

Preferably, the physical model of the distribution boom used for this purpose takes into account the elastic deformation of at least one of the segments.

According to the present invention, the reduction of vibrations of the distribution boom induced by the concrete supply is carried out by prior intervention of disturbances by controlling the actuators of the articulated arm.

In a possible embodiment of the present invention, the pre-intervention of disturbances is carried out as a preventive control without feedback of the dynamic state of the distributor boom. This simplifies control. Preferably, the preventive control is based on a regulation of a virtual model of the distributor boom. Preferably, the pre-intervention of disturbances regulates the virtual model of the distribution boom, which is coupled to the concrete delivery model in the context of determining the disturbance forces. In particular, this regulation may be such that the influence of the disturbing forces at at least one point of the articulated boom is compensated.

In a possible embodiment of the present invention, the disturbance preintervention controls the actuators of the articulated arm in such a way that the influence of the disturbance forces on the tip of the distributor boom is reduced and preferably eliminated.

The supply pump is preferably a double piston pump. Said double piston pump comprises two pistons that work in push-pull to supply the concrete. These types of bombs are known.

The damping of vibrations induced by the prior intervention of disturbances according to the present invention is preferably based on a control of the actuators of the articulated arm.

On the contrary, the control of the supply pump is preferably carried out independently of the previous intervention of disturbances. In particular, the pre-intervention of disturbances can be based solely on a control of the actuators of the articulated arm.

In a possible embodiment of the present invention, in addition to the input of disturbing variables, the control also includes a regulation that is based on a measurement and/or feedback of the position and/or vibration state of the distribution arm.

In particular, the control comprises a vibration damping to damp horizontal and/or vertical vibrations of the distribution arm, which is based on a measurement and/or feedback of the position and vibration state of the distribution arm. In particular, the vibration damping can be designed in such a way as to dampen the natural vibrations of the distributor arm.

The vibration damping is preferably based on a physical model of the distributor arm. In particular, this physical model may be the same model that is also used to determine the influence of disruptive forces from the concrete supply on the placing boom.

The vibration regulation and/or damping is preferably configured in such a way that it only intervenes when the state of the busbar deviates from the state of the virtual model, which is regulated within the framework of the supply of the disturbing variable.

In a second aspect according to claim 9, the present invention comprises a concrete pump with a feed pump, a concrete line and an articulated arm forming a distribution arm, along which the concrete line is guided, the articulated arm having a rotating platform that can rotate about a vertical axis and/or at least one means of a joint that can rotate about a horizontal axis,

In a second aspect according to claim 9, the present invention comprises a concrete pump with a feed pump, a concrete line and an articulated arm forming a distribution boom, along which the concrete line is guided, the articulated arm having a rotating platform. and/or rotating around a vertical axis has at least one segment that can be rotated around a horizontal axis by means of a joint, the rotating support being mobile around the vertical axis through an actuator and/or being at least one segment rotatable about the vertical axis the horizontal axis through an actuator, and wherein the concrete pump continues to provide control of the distribution arm actuators, the control comprising a variable disturbance feed to reduce induced distribution arm vibrations by concrete supply, which takes into account the pressure of the concrete. The second aspect is characterized in that the feed disturbing variable determines the concrete pressure at the inlet of the concrete line based on the operating parameters of the feed pump.

The indirect determination of the concrete pressure according to the invention from the operating parameters of the feed pump has the great advantage that extremely wear-prone pressure sensors in the concrete pipe can be dispensed with.

The determination of the concrete pressure at the inlet of the concrete pipe is preferably carried out based on the hydraulic pressure of the transport cylinders of the transport pump and the surface ratio of the piston of the transport pump. In this way, the concrete pressure can be determined by a measurement value that can be reliably determined in the hydraulic system of the feed pump.

The first and second aspects of the present invention can each be used independently of each other. In particular, the input of the disturbing variable based on a physical concrete supply model can also be performed according to the first aspect without determining the concrete pressure according to the second aspect. Furthermore, a determination of the concrete pressure according to the second aspect can also be used in an injection of disturbance variables, which is based on a different principle than the injection of disturbance variables according to the first aspect.

However, the first and second aspects are preferably used in combination.

Preferred developments of a concrete pump according to the first and/or second aspect are presented in more detail below.

In einer moglichen Ausführungsform der vorliegenden Erfindung berücksichtigt die StorgrolJenaufschaltung die Frequenz der Forderpumpe und/oder die Position und/oder Geschwindigkeit der Forderkolben der Forderpumpe. Auch hier handelt es sich um einfach zugangliche Betriebsparameter der Forderpumpe, welche entweder durch Messung, oder aus der Ansteuerung der Forderpumpe ermittelbar sind, und aus welchen BetriebsgroUen der Betonforderung ermittelbar sind.

Insbesondere kann die StorgrolJenaufschaltung die Stromungsgeschwindigkeit des Betons in der Betonleitung aus der Geschwindigkeit der Forderkolben der Forderpumpe ermitteln. These Merkmal der vorliegenden Erfindung kann auch unabhangig vom ersten und vom zweiten Aspekt der vorliegenden Erfindung zum Einsatz kommen, insbesondere als Weiterbildung einer Betonpumpe gemali dem Oberbegriff von Anspruch 1.

In a possible configuration of the present invention, the feeding of the disturbing variable takes into account the frequency of the feed pump and/or the position and/or speed of the feed pistons of the feed pump. Here, too, these are easily accessible operating parameters of the feed pump, which can be determined by measurement or by controlling the feed pump and from which the operating variables for concrete transport can be determined.

In particular, the supply of the disturbing variable can determine the circulation speed of the concrete in the concrete pipe from the speed of the transport pistons of the transport pump. This feature of the present invention can also be used independently of the first and second aspects of the present invention, in particular as a further development of a concrete pump according to the preamble of claim 1.

In a possible configuration of the present invention, the concrete pump has at least one rotation speed sensor, which is arranged in a segment of the articulated arm, determining the control for the input of disturbing variables and/or the damping of vibrations. Vibration status of the rotation speed sensor based on the values measured by the rotation speed sensor from the vibrations of the individual segments of the entire timing arm.

In a possible embodiment of the present invention, the concrete pump comprises at least one rotation speed sensor, which is arranged in a segment of the articulated arm, the control for the introduction of disturbing variables and/or the damping of vibrations being carried out without the use of geodetic sensors and/or deformation sensors.

In a possible configuration of the present invention, the concrete pump has at least one rotation speed sensor, which is arranged in a front area of a segment that is arranged between the rotating support and a segment that forms the tip of the mast in the articulated arm.

Preferably, the signal from the rotation speed sensor is used to determine the vibrations of the segment where it is arranged. Preferably, the forward region of a segment within the meaning of the present invention is considered to be the forward 25% of the linear expansion of the respective segment, i.e. facing the tip of the boom, preferably the forward 10% of the expansion. linear.

In a possible configuration of the present invention, the rotation speed sensors are arranged in at least two segments. Preferably, the signals from these rotation speed sensors are used to determine the vibrations of the segments in which they are arranged.

Preferably, the vibration damping system determines a vibration state of the segments and/or the entire arm based on the measured values of the at least two rotation speed sensors.

Preferably, the rotation speed sensors are each arranged in a front region of the segments. This improves the detection of vibrations of these segments.

Preferably, the at least two segments in which the rotation speed sensors are arranged are arranged between the rotating support and a segment that forms the tip of the boom on the articulated arm. Furthermore, preferably, another rotation speed sensor is arranged in the segment forming the tip of the pen, which is preferably used to determine the vibrations of the tip of the pen.

According to the first aspect of the present invention, in addition to the rotation speed sensors, the large manipulator further comprises sensors associated with the rotation joints to directly or indirectly measure the respective rotation angle of the joints of the articulated arm, wherein the Measurement signals from the sensors are input into the control system of the large manipulator. These can be used, in particular, to compensate for the drift of the measured values, which is inevitable in the case of rotational speed sensors due to their design.

The measurement signals from the sensors are preferably fed into the vibration damping system. Alternatively or additionally, the measurement signals from the sensors can serve to determine the current position of the articulated arm, and in particular be used for position control of the articulated arm.

In a possible configuration of the present invention, disturbance input and/or vibration damping is performed by a physical model of the distributor arm, where the flexibility of at least one segment is described by a virtual joint arranged within this segment. .

Preferably, at least the flexibility of the segment located directly on the rotating support is taken into account by a corresponding virtual joint, since the vibrations of this segment have the most influence on the vibration state of the articulated arm. Alternatively or additionally, the flexibility of the last segment, which forms the tip of the feather, can be taken into account. This is usually the least stable and, therefore, the most flexible. However, virtual articulation can also be provided in another segment.

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

In one possible configuration of the present invention, the physical model is a rigid body model with actuated joints. Preferably, the model describes several and even more preferably all segments of the articulated arm, and therefore simultaneously reproduces the position of the articulated arm. The vibratory capacity of at least one and preferably several and even more preferably all segments is then described by at least one virtual joint in the rigid bodies describing the actual segments.

In one possible configuration of the present invention, a spring element and a damping element are associated with the virtual joint. This can be used to describe the flexibility of the segment. Preferably, the spring constant and the damper constant are chosen such that the virtual joint describes the magnitude of the deflection and/or torsion and/or the first eigenfrequency of the real segment. Therefore, the virtual articulation can be considered as a first description of the first proper oscillation of the segment in frequency and amplitude.

In one possible configuration of the present invention, less than 10, more preferably less than 5, more preferably less than 3, and in one possible configuration exactly one virtual joint within the segment are provided. This reduces the complexity of the model.

If only vertical or horizontal vibration is considered, a virtual joint with a single axis of rotation is sufficient. In particular, a virtual joint with a horizontal axis of rotation can be used to damp vibrations in the vertical.

However, in a preferred configuration of the present invention, the virtual joint has at least two and preferably three degrees of freedom of movement.

In a possible configuration of the present invention, the vibration damping takes into account the torsion of at least one segment and/or of the articulated arm.

In a possible configuration of the present invention, consideration of the twisting of at least one segment and/or of the articulated arm is carried out using a physical model of the articulated arm that describes a twisting of the articulated arm and/or of one or more segments of the articulated arm. Furthermore, this is preferably done through a virtual rotary joint, as described above, which extends in the longitudinal direction of the segment.

In a possible configuration of the present invention, the articulated arm comprises at least two rotation speed sensors arranged in different segments, where the torque is determined from a comparison of the measured values of the rotation speed sensors.

For example, the measured values of a first rotation speed sensor disposed within the articulated arm closest to the rotating support can be compared with the measured values of a second rotational speed sensor disposed within the articulated arm closest to the tip of the boom to determine the torque of the articulated arm between the two rotation speed sensors.

Alternatively or additionally, the measured values of a first rotational speed sensor disposed in a first segment may be compared with the measured values of a second rotational speed sensor disposed in a segment following the first segment within the articulated arm to determine the torque. of the articulated arm between the two rotation speed sensors and, in particular, the torsion of the first or second segment. For this purpose, the rotation speed sensors can, for example, each be arranged in a front region of the segments.

Alternatively or additionally, the articulated arm may comprise at least two rotation speed sensors arranged at different positions of the same segment, in which case the torque of the segment is determined from a comparison of the measured values of the rotation speed sensors. . Preferably, for this purpose, the rotation speed sensors are arranged in a front and a rear region of the segment.

Furthermore, at least one of the rotation speed sensors, which is used to determine the torque, may be arranged on the rotating support and/or in a rear region of the segment arranged directly on the rotating support, and/or at least one of the rotation speed sensors, which is used to determine the torque, can be arranged in the last segment of the articulated arm and, in particular, in the region of the tip of the boom.

Preferably, the rotation speed sensors whose measured values are used to determine the torque have at least two sensitivity directions, in particular a first horizontal sensitivity direction and a second sensitivity direction extending in a vertical plane. This allows the torque to be determined relatively easily by comparison.

However, also independently of the determination of the torque, the rotational speed sensors whose measured values are included in the vibration damping according to the invention preferably have at least two sensitivity directions, in particular a first horizontal sensitivity direction and a second direction of sensitivity that extends in a vertical plane.

In a possible configuration of the present invention, the articulated arm comprises an observer that estimates the state of the articulated arm. In particular, the observer can understand a physical model of the articulated arm and estimate its state based on the model and measured values from the sensors.

Preferably, the estimation is carried out on the basis of the measured values of sensors as already described above, in particular on the basis of at least one rotation angle sensor and/or the sensors associated with the joints to directly or indirectly detect the angles of rotation of the joints.

Preferably, the observer uses a physical model of the articulated arm, as described in more detail above, in particular a physical model that also serves to determine the influence of disturbing forces on the articulated arm by input of disturbing variables.

Preferably, the observer estimates the position and/or vibration state of the articulated arm.

If, in the context of the present invention, reference is made to a state being determined, this comprises in particular an estimate of the state by an observer.

According to the invention, in a possible configuration the vibration damping could be carried out only as a pilot control. However, vibration damping preferably includes feedback regulation of at least one magnitude obtained by a measurement signal.

In a possible configuration of the present invention, the vibration damping comprises a control that is carried out by feedback at least one of the following quantities: speed and position of one or more of the joints, speeds and positions of flexion and/or twisting of one or more of the segments.

Preferably, the magnitude or magnitudes fed back by the control are estimated by an observer. In particular, the observer that has been described in more detail above can be used for this purpose.

In a possible configuration of the present invention, an estimation of the state of the system and/or the vibration damping and/or the determination of the influence of disturbing forces on the articulated arm is carried out based on a linearization of a physical model, and in particular on the basis of a linearization of the physical model, as described above. In particular, the estimation is performed by an observer and/or control and/or input of disturbing variables, as described above, on the basis of linearization.

Preferably, the linearization is performed around the equilibrium position of the current position of the articulated arm. Linearization can be performed by the control system based on the current position of the articulated arm.

In a possible configuration of the present invention, the control system comprises a preventive control that calculates control signals from a reference value predetermined by an operator, by which the desired movement of the boom is realized and an excitation is reduced. vibration of the articulated arm.

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

In a possible configuration of the present invention, the control system comprises axis regulators associated with the respective joints, where the control system generates control signals for the reference angular speed of the axes, based on which the regulator of axis associated with the respective joint generates control signals for the respective actuator, wherein the axis regulators are preferably based on inverse deflection kinematics and/or comprise inverse nonlinearity.

In a possible embodiment of the present invention, the articulated arm comprises a rotating support that can rotate around a vertical axis and at least two segments that tilt around horizontal axes by means of joints, in which case the rotating support is displaceable around the vertical axis by means of an actuator and the segments are tiltable around the horizontal axes by means of actuators. Furthermore, preferably, the articulated arm comprises at least three and more preferably at least four segments. Preferably, the control system, and in particular the supply of disturbing variables and/or the vibration damping system, controls all the actuators of the segments and/or the rotating support.

In a possible configuration of the present invention, at least vertical damping of vibration and/or input of disturbing variables is carried out. For this purpose, the system for damping vibrations and/or disturbing variables controls the actuators through which the segments of the articulated arm are rotated around their horizontal axes of rotation.

In a possible configuration of the present invention, at least horizontal damping of vibration and/or feeding of disturbing variables is carried out. To this end, the vibration damping system controls the rotary bracket actuator accordingly.

The actuators are preferably hydraulic actuators. The hydraulic actuators are preferably driven by a hydraulic pump, which is driven by the traction motor of the concrete pump.

Hydraulic cylinders are preferably used as actuators to tilt the segments.

Preferably, a hydraulic motor is used as an actuator to rotate the rotating bracket.

Preferably, the segments of the articulated arm can be folded together across the joints in a transport position, where preferably the individual segments are substantially parallel in the transport position.

In a possible configuration of the present invention, the control system comprises a geometric control that, through instructions from a user, which are preferably carried out by means of hand levers, and/or by means of a predetermined trajectory of the tip of the The boom, which is preferably generated automatically, controls the actuators of the articulated arm joints to generate a corresponding movement of the boom tip.

The present invention further comprises a control system according to claim 14.

The control system preferably comprises a microprocessor and a memory in which the control software is stored which, when executed by the microprocessor, implements the structure and/or operation 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 the sensors, in particular the sensors described above, and/or one or more outputs through which it controls the actuators described above.

The disturbance input and/or vibration damping according to the invention is preferably carried out automatically by controlling the concrete pump.

Furthermore, the present invention comprises a control software according to claim 13

The control software implements the control system according to the invention. The control software may be stored in memory and/or constitute a computer program product.

In particular, the concrete pump according to the invention is a truck-mounted concrete pump. Preferably, the concrete pump includes a chassis through which it can be moved. The chassis preferably includes several axles with wheels.

The present invention further comprises a method according to claim 15.

According to a first aspect of the present invention, in the method according to the invention it is provided that the connection of the disturbing variables is carried out on the basis of a physical model of the concrete delivery, which describes the disturbing forces related to the flow during the delivery of the concrete on the placing boom.

According to a second aspect of the present invention, the method according to the invention provides that the pressure of the concrete at the entrance of the concrete line is determined based on operating parameters of the feed pump, in particular based on the hydraulic pressure of the feed cylinders and the piston area ratio of the feed pump.

The processes of the present invention are preferably carried out as described above.

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

In them:

Fig. 1 shows an exemplary embodiment of a large manipulator according to the invention and a truck-mounted concrete pump according to the invention,

Fig. 2 shows a schematic representation of an exemplary embodiment of a control system according to the invention with a vibration damping system and disturbance pre-intervention,

Fig. 3 shows a schematic representation of a preventive control such as can be used in a control according to the invention,

Fig. 4 shows a schematic representation of an exemplary embodiment of a control system according to the invention with vibration damping,

Fig. 5 shows a schematic representation of an axis regulator as it may be used in a control system according to the invention,

Fig. 6 shows a schematic representation of the disturbing forces acting on the articulated arm due to the supply of concrete,

Fig. 7 shows a schematic representation of an exemplary embodiment of a control system according to the invention with a prior intervention of disturbances,

Fig. 8 shows a schematic representation of another exemplary embodiment of a control system according to the invention with a prior intervention of disturbances, which is based on a physical model of the concrete supply,

Fig. 9 shows a schematic representation of another exemplary embodiment of a control system according to the invention with a prior intervention of disturbances, which is based on an estimation of the disturbing forces from measured values of the position and/or the vibration status of the distributor boom.

0. Introduction

New design procedures, materials and electronic systems have led to constant development of concrete pumps in recent decades. The use of articulated arms of several members with increasingly longer segments allows improving accessibility to areas that are difficult to access. However, increasing the number and length of segments also increases the weight and dimensions of the vehicle. The consequence is restrictions on road travel, maneuverability and functionality of the concrete pump.

A special phenomenon of large manipulators is the ability of the distributor boom to vibrate. Vibrations make it difficult for the operator to control the boom and distribute concrete for the final hose operator. The vibration capacity is linked to the slenderness and inertia of the segments and the elastic properties of the material.

Vibratory excitation comes from the movement of the folded boom and the delivery of concrete. The typically used double-piston concrete delivery pump transmits impulse-like disturbance forces to the distribution boom, thereby causing continuous vibratory excitation. Depending on the position of the boom and the transport frequency, excitation close to the boom's own frequencies is also possible.

The combination of translational motion and concrete delivery exposes the placing boom to continuous vibratory excitation during normal operation. This has consequences for the useful life of the machine and the safety of the operator.

The object of the present invention is to dampen the vibrations of the distribution boom to improve the manageability and operability of the concrete pump.

1. State of the art

Publication EP 2 103760 B1 (Cifa) proposes vibration damping using a modal model. The regulation algorithm estimates the state of the system with the help of an observer and feeds back the estimated signal through regulation amplifications. The amplifications are retrieved from a list based on the position of the pen and interpolated. The procedure is based on a modal model obtained by modal transformation and subsequent reduction of the model to the first oscillation modes. The individual states of the model are therefore modal coordinates and have no physical interpretation. The procedure has the drawback that, in addition to the regulation amplifications, the reduced modal model of the observer also depends on the current position of the plume. Therefore, the modal model must be regenerated for each pen position or is only valid for certain pen positions. Due to the large number of possible boom positions, this represents a limitation for the applicability of vibration damping. The vibration damping proposed below avoids these problems through a different type of modeling. The model reduction is physically motivated and leads to physically interpretable elastic coordinates. Additionally, the sensor combination used for vibration damping is different.

Publication WO 2014165889 A1 (TTControl) presents a vibration damping system based on feedback of position and deformation signals of the boom segments. The position is measured by an inertial measurement unit and the deformation by strain gauges. The inertial measurement unit comprises a rotation speed sensor and an acceleration sensor, which are only used in combination and for position estimation (see claim 2). The method has the advantage that the vibration of the segments is detected independently of the displacement movement. This eliminates additional signal processing to separate displacement motion from superimposed structural vibration. However, the use of strain gauges has the disadvantage that the assembly is complex and must be carried out at points of the segment subjected to great stress. Furthermore, the sensor is very sensitive to temperature and requires a lot of calibration effort. The vibration damping system proposed below overcomes these disadvantages by choosing a rotation speed sensor to detect vibrations in the distributor boom.

In publication WO 2016 131977 A1 (Schwing) inertial measurement units are used to control the position of the pen tip. The measurement units are mounted on the center segments of each beam. An additional sensor is provided at the tip of the pen. The acceleration and rotational speed signals from the sensors are fused using a rigid body approach and estimate the position of the boom tip. To improve the attitude estimation, the acceleration signal from the sensor located at the tip of the boom is integrated twice and merged with the existing estimate. Determination of the absolute position is not possible due to the rigid body approach used and the double integration. Instead, the dynamic components of the boom position are calculated using a high-pass filter and fed back to a PID control system. A subordinate position control at joint level prevents boom tip drift effects. The fusion algorithm only includes the reconstruction of the pen tip position. Due to the position of the inertial measurement units and the rigid body approach used, only the inclination of the segments is estimated and not the vibration state of the distributor boom. This differs from the model-based approach to estimating and controlling the vibration state of the distributor boom presented below. The vibration state of the entire boom is taken into account here. Unlike boom tip position control, the number of sensors used can be reduced and limited to the use of rotation speed sensors.

EP 1537282 B1 (Putzmeister) proposes geodetic angle sensors for position determination and vibration damping of the distribution boom. The sensors are mounted on the segments and provide the respective absolute inclination. Taking kinematics into account, the signals are divided into a low-frequency component for coordinate control and a high-frequency component for vibration damping. Commonly used tilt sensors react sensitively to peaks in travel acceleration. Therefore, the application for vibration damping considering translational motion and concrete supply is very limited.

Publication EP 2778466 A1 presents a vibration damping system in a horizontal plane.

Publication EP 1122380 B1 (Putzmeister) proposes a control device to periodically vary or modulate the frequency of the pump. The variation or modulation of the pump frequency prevents excitation frequencies from occurring close to the plume's own frequency. The result is less vibration excitation of the distributor boom. The procedure modifies the concrete supply to dampen vibrations in the distribution boom. This differs from the disturbance preintervention shown below, which uses the spreading boom actuator and does not affect concrete delivery.

Publication EP 1537 282 B1 (Putzmeister) describes a disturbance control system for reducing vibrations of the distributor boom. However, this is not a pre-intervention of disturbances, since a disturbance magnitude is not used to damp the vibrations, but rather a measured magnitude of the distributor boom. The measured magnitude is the dynamic component of the boom position detection. It is amplified by a regulator and fed back to the distributor boom actuators. The method thus represents classical vibration damping based on feedback and not preintervention of disturbances.

DE 101 01 570 B4 (Schwing) describes a disturbance pre-intervention combined with feedback-based vibration damping according to the principle of the virtual spring damping element. The measured perturbation magnitude depends on the concrete supply, but no explicit model-based conversion is performed on the spreading boom perturbation forces. Furthermore, the procedure presented is decentralized for each joint. Therefore, the influence of disturbing forces on the entire distribution boom is not taken into account. The proposed sensor system for measuring the pressure of concrete flow in the transport pipeline cannot be used in practice, as it is expensive and subject to high wear during operation.

2. Construction of the design example in the form of a truck-mounted concrete pump

Fig. 1 shows the relevant elements of the truck mounted concrete pump. It has an undercarriage with a multi-axle chassis with tires, through which the truck-mounted concrete pump can travel on the road. Front and rear support cylinders 9 and 10 are provided on the lower carriage, which are arranged on deployable and/or telescopic struts 10 and 12. Additionally, a distribution box 11 is shown.

The undercarriage carries a pump group 1 at the rear and, via a boom block 2, an articulated arm along which a supply pipe, not shown, is guided.

The articulated arm consists of a rotating support 3 and four segments 4 to 7 (any number of segments is possible), which are coupled by joints A to E. Joint A on the vehicle allows the pump group to be moved. Joint A on the vehicle allows the rotation of the rotating support 3 around the vertical axis, joints B to E allow the rotation of segments 4 to 7 around tilting horizontal axes. The drive system of the concrete pump consists of hydraulic cylinders 14 to 17 in the respective joints B to E and a hydraulic motor for the swivel joint A of the swivel bracket. Hydraulic cylinders 14 to 17 allow the movement of the distributor boom in the vertical plane. The hydraulic motor rotates the entire boom around the vertical axis. The pen tip 22 (TCP) is the top of the distributor pen.

A supply pipe is connected to the distribution boom, which transports the concrete to the tip of the boom 22. From there, the concrete is transported to an operator through a length of hose 8. A double-piston pump of the delivery unit pump 1 generates the necessary transport pressure.

The planned structure of the vibration damping system is divided into the subsystems shown in Fig. 2: geometric control, pre-control, regulation (with observer) and pre-disturbance intervention.

For each subsystem, the structure and mode of operation are described below, along with characteristic features.

3. Geometry control (TCP control)

Geometric control is used to generate distribution boom movement trajectories. Motion trajectories are a temporal function of position, velocity, acceleration and/or jerk of the boom joint axes. They adapt to the dynamics of the system in preventive control and are transmitted to the control as a reference value.

4. Preventive control

4.1 Function

The preventive control according to Fig. 3 serves to ensure that the distributor boom moves quickly without exciting the natural frequencies.

- Measurement of the position of the distributor boom.

- Determination of the (first) natural frequencies and the damping of the distribution boom in the respective position of the boom (rest position) in the horizontal and vertical plane.

- Filtering of reference value signals with natural frequencies (notch filter, input shaping).

- Preventive control acts on each vertical and horizontal actuator.

4.2 Sensors

- Distribution boom position

- Rotation encoder for the rotation angle around the vertical axis

4.3 Actuators

- Hydraulic cylinder (vertical plane)

- Hydraulic motor (horizontal plane)

5. Regulation

The regulation system, shown again in Fig. 4, is divided into two parts: the shaft regulation (Fig. 5) and the regulation system for damping vibrations and the position regulation with the regulation system and the observer.

5.1 Shaft regulator

The axis controller according to Fig. 5 serves to convert the reference angular speed of the joint into the actual speed of the actuator:

- The transmission behavior of the hydraulic system from the control to the speed of the actuator presents a non-linear behavior.

- Axle regulation compensates for non-linearities in the hydraulic system and deflection kinematics. - The control algorithm consists of inverted static characteristic curves of hydraulics and deflection kinematics. Possibly, feedback of pressure or cylinder position or velocity is provided. - The axle regulation is used in a decentralized manner in each joint and represents the lowest level of the overall vibration damping system.

In its function of converting the reference speed into the actual speed of the actuator, the axis regulation is implicitly assumed for all subsequent control and regulation concepts.

5.2 Vibration damping based on rotation speed sensors

5.2.1 Structure of vibration damping

The procedure includes active vibration damping to reduce vibrations in the distributor boom. A distinction is made between the nominal movements of the segments by the operator and the vibrations excited by the translational movement. Vibration damping takes into account the nominal movement and dampens only the structural vibrations that occur. Vibrations due to concrete delivery are also reduced.

The goal of vibration damping is to reduce vibrations throughout the distributor boom. To do this, the vibration state of the entire boom is calculated from the vibrations of the individual segments. The distribution boom has variable natural frequencies depending on the position and inclination of the segments. Vibration damping takes into account this variability of the natural frequencies depending on the position of the boom. The first natural frequencies are the ones that most influence the vibratory behavior.

5.2.2 Sensors

The vibration state of the distributor boom is detected by the rotation speed sensors 18 to 21. The sensors are mounted on one or more segments 4 to 7 and measure the rotation speed around the joint axes. The advantage of these sensors for vibration detection is that they can be easily mounted, unlike common sensor technology (e.g. strain gauges). The sensor can be mounted on all exterior and interior sides of the segment. MEMS-based rotational speed sensors are also cost-effective, robust and require little maintenance.

The rotation speed sensor 18 to 21 is mounted in the forward region of the respective segment 4 to 7 to optimally detect structural vibrations. Due to the serial kinematics of the manipulator, the measured rotational speed of one segment also contains the vibration of the previous segment. This circumstance will be taken into account in the regulation design.

The position of the distributor boom is determined by direct or indirect measurement of the relative hinge angles between the segments. For example, the measurement arrangement may be a detection of relative joint angles using rotation angle encoders.

5.3.3 Modeling

The regulation design is based on a mathematical model of the distributing boom. To do this, the mechanical system is represented by a dynamic model.

The delivery boom is modeled using a rigid body model with actuated joints B to E. Additional virtual joints take into account flexibility in the segments. Additional virtual joints take into account flexibility in the segments. An additional virtual joint with spring and damping elements is introduced for each segment. The spring and damping constants are chosen so that the deflection and the first eigenfrequency of the real segment are maintained. The distribution boom model is made up of several segments. The stiffness of the overall structure is therefore the result of the stiffness of the individual segments. Since the overall structure is made up of several segments, the highest eigenfrequencies are also reproduced.

This type of modeling represents a physically motivated discretization of the elastic distributor boom of infinite dimensions. The advantage is that well-developed and efficient rigid body formalisms can be used for modeling. Furthermore, the resulting model has a relatively low system order. Unlike the reduction of a modal model, the system state of the virtual joints remains a physical variable. Describes concentrated flexion and vibration of the segment.

The nonlinear model of the distributing boom is linearized around the equilibrium position of the current position of the boom. This gives rise to a linear system dependent on the position and loading situation of the boom, which represents small deviations from the equilibrium position.

5.3.4 Observer

Based on the linearized model, an observer is used to estimate the states of the system.

The observer reconstructs the state of system x with the help of the inputs and outputs of the system. The system inputs u are the reference values of the hydraulic system. The outputs and are the measured values of the position and vibration state of the distributor boom. The fusion of the different measurement signals improves the robustness of the vibration damping against drift phenomena of the rotational speed sensor system caused by the measurement principle. The model-based observer further ensures that the measurement signal from the rotational speed sensors is divided into the separate parts of joint motion and vibration. In this way, the regulation specifically dampens structural vibrations without influencing the reference movement. The amplification of the observer L is selected by a suitable procedure such as pole pre-specification or by a Kalman filter.

5.3.5 Regulation amplification

The linearized model is used to design the feedback amplifications K of the regulation circle.

The poles are positioned in the complex half-plane in such a way as to increase the damping of the system. This dampens the vibrations of the distributor boom. The regulator receives the estimated state of the observer x, amplifies the signals and feeds them as reference values to the hydraulic system (see Fig. 4). The regulation amplification K is calculated by a suitable procedure such as pole pre-specification or optimization-based procedures (LQR).

The design process for the observer and regulator described above applies to a specific balance position of the distributor boom. Therefore, if the position of the pen is changed, the design process is repeated and adapted to the current position. By monitoring control parameters, vibration damping functionality is ensured for each boom position.

The cyclic design of the observer and regulator makes the amplifications dependent on the current position and loading situation of the distributor boom. In this way, the variable natural frequency of the boom is implicitly taken into account in the regulation design.

5.3.6 Horizontal vibration damping

Vibration damping can also be used for vibrations in the horizontal plane. The hydraulic motor on the boom support serves as the actuator. The position of the boom around the vertical axis is detected by an angle encoder. In this case, the rotation angle sensors for vibration measurement are designed or extended by a sensing direction in the horizontal plane and torsion. The sensors are mounted on one or more segments and measure the speed of rotation around the vertical axis and the longitudinal axis.

In the horizontal plane, the horizontal bending is coupled to the torsion of the segments. The distribution boom thus simultaneously experiences horizontal bending and twisting, depending on the position. This effector is taken into account in the modeling.

A horizontal component is added to the dynamic model of the distribution boom (section 5.3.3). To this end, the virtual joints of the segments are designed as multi-axis rotary joints that detect bending in the horizontal plane and torsion. Rotation around the vertical axis is taken into account by a joint in the swivel bracket. The model type and structure remain the same as in section 5.3.3.

Analogously to the procedure described in sections 5.3.3, 5.3.4 and 5.3.5, an observer and a feedback amplifier are designed for the extended linearized model. A separate horizontal vibration damper or a combined vertical and horizontal vibration damper can be implemented. The model-based observer ensures that the measurement signal from the rotational speed sensors is divided into the separate components of vertical axis motion and vibration. In this way, the regulation specifically dampens structural vibrations from horizontal bending and torsion without influencing the nominal movement.

5.3.7 Other properties

Vibration damping explicitly takes into account the operator's movement specifications. This means that the desired displacement movement is allowed by the regulation and only superimposed structural vibrations are damped. To reduce vibration excitation during travel, pre-control is also provided. It calculates control signals from the operator's reference value that execute the desired movement of the boom and do not cause any vibration. For this, a notch filter is used, which suppresses the natural frequencies of the distributor boom during the travel movement depending on the current position of the boom (see Fig. 3).

The reference value signals for the hydraulic system are converted by slave axis control in the cylinders. Axis regulation converts a reference angular velocity specification u of the joints into the actual translational velocity of the cylinders. Deflection kinematics and non-linearities of the hydraulic system are taken into account by pre-control (see Fig. 5). Pressure, cylinder position or cylinder speed can be used as measuring variable for feedback. Alternatively, the cylinder speed can also be calculated from the position by separate signal processing. The cylinders transmit the Fu force to the distribution boom and thus generate a movement of the joints. As described above, axis regulation is decentralized and subordinated separately to each joint.

6. Prior intervention of disturbances

Traditionally, feedback-based vibration damping controls are used to reduce boom vibrations. These controls are based on feedback from the static and dynamic parameters of the distribution boom. To do this, the vibrations of the structure are measured, processed with a control algorithm and returned to the concrete pump drive system as an adjustment signal. The movement generated by the actuator system acts on the distributor boom and actively dampens vibrations. A disadvantage of this procedure is that vibrations can only be compensated for when measured at the boom. This means that vibrations must first occur in the structure in order to be damped. The procedure described below follows a different approach based on the principle of preintervention of disturbances. This procedure dampens system vibrations based on cause and not effect, as is the case with feedback-based procedures (see Fig. 7). The vibratory excitation of the spreading boom is largely due to the cause of concrete supply. Consequently, it represents a disturbing magnitude of the system that must be compensated.

The advantage of disturbance pre-intervention over traditional vibration damping is that disturbances can be compensated before they affect the system. This means that the excitation of the concrete delivery is removed before it is visible as vibration in the placing boom.

The objective of disturbance pre-intervention is therefore to reduce the vibrations of the distribution boom based on the characteristic measurement quantities of the concrete supply. The measured variables describe the state of concrete delivery and not the vibration state of the placing boom. Typical measurement quantities for concrete transport are the pressure at the inlet of the supply pipe, the frequency of the pumping process and the position and speed of the transport piston.

The disturbing forces in the distribution boom are reconstructed with the measured magnitudes by a model of the concrete delivery and are amplified and connected to the drive system. The amplification can be designed in such a way as to eliminate the influence of disturbing forces at a given point on the distributor boom. To do this, the tip of the boom is chosen to keep the position of the final hose stable and constant.

Two procedures are proposed to reduce oscillations due to concrete supply: disturbance preintervention based on the classical model and disturbance preintervention with a disturbance observer.

6.1 Classical model-based pre-disturbance intervention

6.1.1 Summary

6.1.1.2 Function

The disturbing forces shown in Fig. 6 are calculated using a mathematical model of concrete delivery along the boom.

- Calculation of the disturbing forces in the distribution boom from the concrete supply measurement signals (pressure, frequency, cylinder position) using the concrete supply model (see Fig. 8). - Calculation of the influence of the disturbing forces on the distribution boom in the disturbance model. - State control of the disturbance model. The setting magnitude u<d>of the controlled disturbance model is the setting magnitude u of the hydraulic system of the concrete pump.

- Status monitoring can be expanded with output feedback. In this case, the movements of the pen tip are damped.

- The operating point is the current position of the distributor boom. When the position of the boom is modified by a translation movement, the operating point is followed. That is, the height of the boom tip after the movement represents the new working point.

- Deviations from the nominal value y<d>(see fig. 8) are compensated by a regulation circuit with the actual measured values of the concrete pump y. This regulation circuit can represent the vibration damping of section 5.2.

6.1.1.2 Notes

- The additional control circuit of the disturbance model allows compensation of the disturbance magnitudes F<d>independently of the external control for vibration damping (measuring signal y). Since the state regulator applies a virtual perturbation model, the full state x<d>is available. - Adjustment magnitude limitations can be easily taken into account by limitations in the disturbance preintervention control circuit.

6.1.1.3 Sensors

- Distribution boom position

- Measured values for concrete supply: cylinder amplitude or position, cylinder speed, pump frequency and/or concrete pressure at the entrance of the supply pipe.

6.1.1.3 Actuators

- All hydraulic cylinders (vertical plane)

6.1.2 Implementation example

6.1.2.1 Modeling

Concrete delivery modeling forms the flow of concrete in the delivery pipe from the delivery pump on the vehicle to the final hose at the tip of the boom. Disturbance forces related to the flow of concrete supply in the distribution boom are calculated.

The generation of disturbing forces is mainly due to friction forces on the inner wall of the pipe and inertia forces caused by the deflection of the concrete flow at pipe bends. Due to the unstable and periodic transport, impulsive forces arise that are transmitted to the distribution boom through the pipe fixings. The forces depend on various factors. The greatest influence is the rheological properties and composition of the concrete. Depending on the type and consistency of the concrete, the vibration excitations in the spreading boom vary greatly. Another factor is the so-called wall effect. Due to the viscosity and inhomogeneous composition of the fluid, a boundary layer with a low elastic limit and viscosity is formed in the wall region during transport. The boundary layer acts as a lubricating film and reduces friction forces in the wall region. Other factors are the variable fill level factor on the delivery piston and the amount of air dissolved in the concrete. The uncertainty and variability of the aforementioned factors mean that direct modeling, based exclusively on the material, entails great difficulties. For this reason, measurement-based modeling is proposed. The basic idea is to dispense with the exact illustration of the flow conditions inside the pipe and instead consider only the forces acting on the pipe wall.

The approach uses an equivalent Newtonian fluid to model the friction and inertia forces of the fluid on the pipe wall.

The material properties of the equivalent fluid are determined from the measured magnitudes of the concrete supply. In particular, at least the equivalent fluid viscosity is determined from the concrete pressure and the concrete flow rate. A stored average value for the concrete density is used as the equivalent fluid density.

Here, by assuming an ambient pressure in the final hose and measuring the inlet pressure, the pressure difference across the entire pipeline can be calculated. Taking into account the position of the boom, the hydrostatic pressure loss of the flow is also determined. The output quantities of the model are the concentrated disturbing forces F<d>at each joint of the concrete pump (see Fig. 6).

The effect of the concentrated disturbing forces F<d>is calculated by coupling with a mechanical model of the distributor boom. The mechanical model takes into account the dynamic and elastic deformation of the segments under the influence of disturbing forces throughout the distributor boom.

6.1.2.2 Compensation

The coupled model of the concrete supply and the placing boom is used to design a disturbance pre-intervention based on the model. The model is extended with a regulation circuit to reduce the disturbance magnitudes in the distribution boom (see the regulation circuit of the disturbance model in Fig. 8). Unlike classic feedback, the real section is not controlled, but only the "virtual" model. This has advantages for the regulation design, since there are no uncertainties in the section or disturbing magnitudes. Furthermore, the entire state vector is available without the need to use an observer. The control is designed to minimize the influence of disturbing forces on the boom tip.

To compensate for disturbing forces in the real system, the control variable of the virtual control circuit is connected to the actuator. The result is a preventive control that does not require feedback of the dynamic state of the distribution boom.

6.1.2.3 Control

Disturbance preintervention is combined with traditional vibration damping to compensate for vibrations from boom translational motion and modeling uncertainties. Vibration damping is based on measurement and feedback of the position and vibration state of the distributor boom. Taking into account the virtual outputs y<d>and the measured magnitudes y, the control is designed so that the adjustment magnitudes of the previous intervention of disturbances u<d>act without obstacles on the section. Vibration damping only intervenes if the states of the real section deviate from the states of the virtual model.

6.1.2.4 Additional properties

To determine the pressure of the concrete at the entrance of the section, the hydraulic pressure of the transport cylinders can alternatively be measured. The corresponding concrete pressure results from a conversion with the area ratio of the piston.

In addition, the flow rate of concrete can also be determined from the speed of the transport cylinders.

This avoids the use of a pressure sensor and/or a flow sensor in the supply line, which are expensive and prone to wear.

The efficiency of the disturbance preintervention described above largely depends on the accuracy of the mechanical model and the concrete supply. This leads to performance limitations in the presence of parameter uncertainty and parameter variability.

6.2 Asymptotic disturbance compensation

6.2.1 Summary

6.2.1.1 Function

- Estimation of the disturbing magnitude from the measured vibration values of the distribution boom and the pumping frequency of the concrete supply (see Fig. 9).

- Amplification of the disturbance signal in the disturbance regulator and connection to the concrete pump actuators.

- For stability reasons, disturbance compensation requires vibration damping, which can be constructed, for example, as described in section 5.2.

- Compared to classical disturbance preintervention, the disturbance observer has the advantage that the disturbance signal is estimated entirely from the existing sensors of the vibration damping. This makes the procedure robust to changes in concrete supply parameters.

- The estimation algorithm can be designed, for example, as asymptotic disturbance compensation according to Davison.

- Disturbance compensation is based on the fact that disturbances are estimated/learned from a freely selectable measurement output yd. The objective is to regulate this measurement output yd to a constant value using appropriate tuning variables. A possible selection of the measurement output yd is the height of the boom tip in the vertical plane. Disturbance compensation thus reduces the vibratory movements of the boom tip.

- The operating point is the current position of the distributor boom. When the position of the boom is modified by translation movement, the operating point is followed. That is, the height of the boom tip after movement represents the new working point.

6.2.1.2 Sensors

- Distribution boom position

- Concrete supply pumping frequency

- Measurement of the vibration status of the distribution boom: rotation speed sensors in certain segments

6.2.1.3 Actuators

- All hydraulic cylinders (vertical plane)

6.2.1.2 Notes

- Asymptotic disturbance compensation is based on illustrating intervening disturbance signals by means of a fictitious disturbance model. The disturbance model is integrated into the control circuit and is driven by a selected measuring output until the disturbances at a selected measuring output are compensated. The perturbation model has the property of providing a non-decreasing output signal, even if the excitation signal disappears (stable limit). In this way, disturbance compensation generates the necessary adjustment variables to compensate for the effect of the disturbance variable. - Due to the estimation process, disturbing quantities have at least a temporary effect on the system outputs. This leads to the fact that disturbance compensation is subject to a stabilization process at the beginning and in case of large changes in parameters.

6.2.2 Implementation example

6.2.2.1 Modeling

An alternative procedure to the previous disturbance pre-intervention is presented below. The basic idea of the procedure is to estimate the disturbing forces from the measured values of the distributor boom. The periodicity of concrete delivery is used to establish a modal model of the disturbing forces.

The model is made up of the fundamental frequency and its multiples. The individual states reproduce the oscillation shape of the disturbing magnitude as modal coordinates.

A modal coordinate has no physical meaning, but only represents the respective frequency component in the oscillation form of the disturbing magnitude.

6.2.2.2 Estimation procedure

Based on the modal model, the disturbance forces are estimated by a disturbance observer or asymptotic disturbance compensation from the measured values of the distributor plume. The estimation procedures are based on the internal model principle. The principle defines that a stable control circuit can only completely suppress a disturbance if it has an internal model of the disturbing signal. In this case, the model is stable in limits and only consists of conjugate complex pole pairs of the supply frequencies on the imaginary axis of the complex half-plane. Using the disturbance observer or asymptotic disturbance compensation, the initial state of the modal model is adapted from the measurement signals of the distributor plume. This corresponds to an estimate of the unknown amplitude and phase position of the disturbing forces. The more frequencies the model contains, the more accurately the vibration form of the disturbing magnitude can be represented. However, the larger number of frequencies requires more time to learn the current oscillation shape. During the learning process, a stabilization movement occurs, the amplitude of which increases with the number of frequencies. Therefore, for good interference suppression, the number of frequencies must be selected such that, on the one hand, the disturbing magnitudes are reproduced with sufficient precision and, on the other, the stabilization behavior occurs briefly and with a small amplitude.

6.2.2.3 Regulation

The reconstructed disturbance variables are connected to the actuators of the distributor boom via a controller (see Fig. 9). To ensure system stability, disturbance pre-intervention is combined with vibration damping based on the measured magnitudes of the distribution boom and. The disturbance observer calculates the system states based on the plume model and the disturbance model. The measured quantities are the position of the boom and the vibration state of the distributor boom. In this way, the regulator of Figure 9 amplifies the estimated disturbance magnitudes and system states. Disturbance preintervention can be designed to minimize the influence of disturbing forces on the boom tip.

6.2.2.4 Other properties

Unlike the first procedure, the disturbance observer or asymptotic disturbance compensation learns the disturbance forces from the measured values and the dynamic vibration state of the distributor boom. This makes it possible to reduce the number of sensors for concrete delivery. The required measurement quantity is the pumping frequency, which can be determined in the software via the change times of the transport cylinders. Another advantage of the procedure is its robustness against changes in the parameters of the section and variations in the properties of the concrete.

6.3 Other properties of disturbance preintervention

The disturbance precompensations described above are valid for a specific balance position of the distributor boom. Therefore, if the position of the pen is modified, the design process is repeated and adapted to the current position. By monitoring the control parameters, the functionality of the disturbance pre-intervention is guaranteed for each boom position.

The reference value signals for the hydraulic system are converted by a subordinate axis control in the cylinders. Axis regulation converts a reference angular velocity specification of the joints into the actual translational velocity of the cylinders. Deflection kinematics and non-linearities of the hydraulic system are taken into account by preventive control. Depending on the design, pressure feedback or cylinder position or velocity feedback can be implemented. The regulation of the axle is decentralized and, therefore, subordinated to each joint separately.

The operator's motion specifications are explicitly taken into account by disturbance pre-intervention and vibration damping. This means that the desired translational movement is allowed by the regulation and only superimposed structural vibrations are damped. To reduce vibration excitation during travel, pre-control is also provided. It calculates control signals Wref from the operator's reference value, which execute the desired movement of the boom and do not excite any vibrations. For this purpose, a notch filter is used, which suppresses the natural frequencies of the distributor boom during translational movement depending on the current position of the boom.

The preventive control for disturbance precompensations presented in Figs. 8 and 9 is characterized by a signal block. For dynamic, model-based disturbance preintervention, the precontrol signal Wref is additionally considered in the disturbance model regulation loop.

Claims (15)

1. Concrete pump, in particular truck-mounted concrete pump, with transport pump, concrete pipe and articulated arm forming a distribution boom, along which the concrete pipe is guided, wherein the articulated arm has a rotating support (3) that can rotate around a vertical axis (A) and/or at least one segment (4 - 7) that can rotate by means of a hinge (B - E) around a horizontal axis, where the rotating support (3) can be moved around the vertical axis by means of an actuator and/or the at least one segment (4 - 7) can be rotated around the horizontal axis by means of an actuator (14 - 17) , wherein the concrete pump further has a control for controlling the actuators (14-17) of the dispensing boom, wherein the control comprises variable disturbance activation to reduce vibrations of the dispensing boom induced by the supply of concrete, where The activation of the disturbing variable is carried out by a physical model of the concrete supply, which describes the disturbing forces related to the flow of the concrete supply over the distribution boom, wherein the physical model describes friction forces of the concrete on the inner wall of the concrete line and/or inertia forces due to the redirection of the concrete flow in the bends of the pipe and/or where at least one parameter of operation of the transport pump (1) feeds the activation of the disturbing variable. 2. Concrete pump according to claim 1, wherein the physical model of the concrete transport takes into account the current position of the distribution boom and, in particular, the articulation angles of the hinges (B - E), taking into account preferably the position of the distribution boom and in particular the articulation angles of the hinges (B - E) contribute to the description of the redirection of the concrete flow and/or where the determination of the disturbing forces of the concrete supply on the distributor boom is carried out without measuring the vibration state of the distributor boom or the segments (4 - 7), and/or where the physical model takes into account the hydrostatic pressure loss of the flow, taking into consideration the current position of the distributing pen. 3. Concrete pump according to one of the preceding claims, characterized in that at least one property of the material of the pumped fluid that is introduced in the modeling is determined from operating parameters of the transport pump (1) and/or the transport of concrete, where the viscosity is preferably determined, in particular, from the pressure of the concrete and the flow rate of the concrete. 4. Concrete pump according to any one of the preceding claims, wherein the activation of the disturbing variable is further based on a physical model of the distribution boom, which is coupled to the physical model of the concrete supply, to determine the influence of the disruptive forces determined by the physical model of the concrete supply throughout the distribution boom, where the physical model of the distribution boom takes into account the elastic deformation of at least one of the segments (4 - 7). 5. Concrete pump according to any one of the preceding claims, wherein the activation of the disturbing variable is carried out as an advance control without feedback of the dynamic state of the distribution boom, preferably on the basis of a closed loop control of a virtual model. of the distributing boom. 6. Concrete pump according to any one of the preceding claims, wherein the activation of the disturbing variable controls the actuators in such a way that the influence of the disruptive forces on the tip (22) of the distribution boom is reduced and preferably eliminated. . 7. Concrete pump according to any one of the preceding claims, wherein the control, in addition to the activation of the disturbing variable, also comprises a closed loop control, which is based on the measurement and/or feedback of the position and/or or the vibration state of the distributor boom, wherein the closed loop control preferably comprises vibration damping to damp horizontal and/or vertical vibrations of the distributor boom. 8. Concrete pump according to claim 7, wherein the vibration damping is based on the same physical model of the distribution boom that also serves to determine the influence of the disturbing forces of the concrete supply on the distribution boom, wherein the Vibration damping preferably only intervenes if the state of the distributor boom deviates from the state of the virtual model being controlled in the context of the activation of the disturbing variable. 9. Concrete pump, in particular according to any one of the preceding claims, with a supply pump (1), a concrete conduit and an articulated arm forming a distribution boom, along which the delivery conduit is guided. concrete. wherein the articulated arm has a rotating support (3) that can rotate around a vertical axis (A) and/or at least one segment (4 - 7) that can rotate by means of a hinge (B - E) around a horizontal axis, where the rotating support (3) can move around the vertical axis by means of an actuator and/or the at least one segment (4 - 7) can rotate around the horizontal axis by means of an actuator (14 - 17), wherein the concrete pump further has a control for controlling the actuators of the dispensing boom, wherein the control comprises an activation of a disturbance variable to reduce vibrations of the dispensing boom induced by the supply of concrete, the activation of which takes into account the concrete pressure, characterized in that the activation of the disturbance variable determines the concrete pressure at the inlet of the concrete line based on the operating parameters of the supply pump (1), in particular based on the hydraulic pressure of the supply cylinders and the piston area ratio of the supply pump. 10. Concrete pump according to any of the preceding claims, wherein the activation of the disturbing variable takes into account the frequency of the supply pump (1) and/or the position and speed of the supply pistons of the pump. supply. 11. Concrete pump according to one of the preceding claims with at least one angular velocity sensor (18 - 21) arranged in a segment (4 - 7), the control being based on the activation of disturbing variables and/or the damping of vibrations. Based on the measured values of the angular velocity sensor (18 - 21), from the vibrations of the different segments (4 - 7), a vibration state of the entire distributor boom is determined and/or produced without the use of geodetic sensors and/or at least one angular velocity sensor (18-20) is arranged in a frontal region of a segment (4-6), which is arranged between the rotating support (3) and a segment (7) which forms the tip of the boom (22) on the articulated arm. 12. Concrete pump according to any one of the preceding claims, wherein the activation of the disturbing variables and/or the vibration damping is carried out by means of a physical model of the distribution boom, in which the flexibility of at least one is described. segment (4 - 7). by means of a virtual hinge arranged within this segment (4-7), wherein a spring element and a damping element are preferably associated with the virtual hinge, wherein the spring constant and the damping constant are preferably further selected so that the virtual hinge describes the deviation, torsion and/or first natural frequency of the real segment (4 - 7). 13. Control software for a concrete pump according to any one of claims 1 to 12, wherein the control software in its execution implements a control to control the actuators of the distribution boom of the concrete pump with activation of a disturbing variable. to reduce vibrations of the distribution boom induced by concrete delivery, where the activation of the disturbing variable a) is carried out on the basis of a physical model of the concrete supply, which describes the disturbing forces related to the flow of the concrete supply over the placing boom, wherein the physical model describes friction forces of the concrete on the inner wall of the concrete line and/or inertia forces due to the redirection of the concrete flow in the bends of the pipe and/or where at least one parameter of operation of the supply pump (1) feeds the activation of the disturbing variable, I b) determines the pressure of the concrete at the inlet of the concrete pipe based on the operating parameters of the supply pump (1), in particular based on the hydraulic pressure of the transport cylinders and the piston ring ratio of the supply pump. 14. Control for controlling the actuators of the distribution boom of a concrete pump according to any one of claims 1 to 12, wherein the control comprises an activation of a disturbance variable to reduce vibrations of the distribution boom induced by the supply of concrete, where the activation of the disturbing variable a) is carried out on the basis of a physical model of the concrete supply, which describes the disturbing forces related to the flow of transport of the supply over the distribution boom, wherein the physical model describes friction forces of the concrete on the inner wall of the concrete line and/or inertia forces due to the redirection of the concrete flow in the bends of the pipe and/or where at least one parameter of operation of the supply pump (1) feeds the activation of the disturbing variable, I b) determines the concrete pressure at the inlet of the concrete pipe based on the operating parameters of the supply pump (1), in particular based on the hydraulic pressure of the supply cylinders and the area ratio of the piston the supply pump. 15. Method for controlling the actuators of the distribution boom of a concrete pump according to any one of claims 1 to 12, wherein the activation disturbance variable a) is carried out on the basis of a physical model of the concrete supply, which describes the disturbing forces related to the flow of the concrete supply over the placing boom, wherein the physical model describes friction forces of the concrete on the inner wall of the concrete line and/or inertia forces due to the redirection of the concrete flow in the bends of the pipe and/or where at least one parameter of operation of the supply pump (1) feeds the activation of the disturbing variable, and/or b) determines the concrete pressure at the inlet of the concrete pipe based on the operating parameters of the supply pump (1), in particular based on the hydraulic pressure of the supply cylinders and the area ratio of the piston the supply pump.