Coordinate machine with adaptive damping unit

Abstract

Coordinate machine with adaptive damping unit. The invention relates to an adjustable damping unit (2, 2a-2d) designed for integration into a kinematic chain of a machine (1) designed for coordinate measuring and / or coordinate handling of a workpiece (O). The adjustable damping unit (2, 2a-2d) is configured for locally adaptive damping of varying oscillations of a measuring and / or handling tool (4) connected to an endpiece (12) of the kinematic chain during operation of the machine (1). The adjustable damping unit (2, 2a-2d) comprises an adjustable electromechanical damping element whose properties are dynamically adjustable in dependence on actual kinematic and / or position sensor data of the kinematic chain. The adjustable properties include at least one of the following: elastic properties, inertial properties and / or energy dissipation properties.

Description

Technical Field

[0001] This invention generally relates to coordinate measurement and / or machining machines. Background Technology

[0002] Machines that inspect or process workpieces in an oriented manner by determining coordinates in a measurement or workspace are known in the art. More specifically, such coordinate machines are embodied in coordinate measuring machines (CMMs) or CNC machining tools.

[0003] For example, it is common practice to use such robotic equipment to manipulate workpieces according to nominal coordinates (e.g., cutting, drilling, or polishing), or to inspect objects on coordinate positioning devices during or after production to check whether predefined object parameters (such as the object's size and shape) are correct. For example, for measuring surface changes, it is known in the art to be based on measurement principles using tactile and optical sensors.

[0004] In 3D coordinate measuring and / or machining machines, tools such as measuring probes or sensor heads, machining tool heads, or end effectors are supported by a kinematic chain of a robotic arm to move along three, for example, mutually perpendicular axes (X, Y, and Z directions) or about three or more degrees of freedom (DoF). This kinematic chain can include multiple transmission components connected together by joints. The end of the arm opposite to the probe is typically coupled to a movable or fixed base. Thus, the payload can be directed to any point in the volumetric space of the coordinate machine, thereby monitoring its actual position in space.

[0005] In order to perform position monitoring and coordinate data acquisition, in this implementation of a coordinate machine, a proper arrangement of sensors or position encoders can accurately determine the position of the end piece of the motion chain relative to the machine base, thereby determining the coordinates of the measurement point or processing point on the object being approached by the mounting tool at the end of the motion chain.

[0006] Typically, the determination of motion is broken down into individually measured single degrees of rotation (DoFs). For example, for a joint in a kinematic chain, each DoF is measured using a dedicated joint rotation sensor. At each point in the workspace, the position of each joint at a specific moment must be determined. Therefore, each sensor outputs an electrical signal that varies according to the joint's movement in that degree of freedom. The tool typically also generates signals. These position and tool signals are transmitted via the arm to a recorder or analyzer. The position signals are then used to determine the coordinates of the measuring or machining tool within the machine's operating range.

[0007] Several potential sources of error exist regarding the accurate determination of coordinates. In this context, the linear or angular dynamic deflection of the coordinate measuring machine's arm structure caused by the machine's acceleration about an axis must be considered. Resonance or vibration of machine parts when one frame assembly moves relative to another is an example of dynamic error. Furthermore, errors caused by vibrations from outside the machine should also be considered.

[0008] Such errors should also be considered in the context of weight reduction, especially for kinematic chain components, which is an important issue related to the design of coordinate measuring machines. Lighter (less stiff) movable mechanical components can be positioned or moved faster and with less effort, thereby reducing energy consumption. On the other hand, the effects of machine vibration and torsion caused by reduced stiffness and (faster) movement of machine components may increase with the reduction in the weight of these components. Therefore, the uncertainty of the obtained measurement values ​​and the errors caused by these deformations and vibrations may also increase accordingly.

[0009] Dynamic measurement errors can be reduced by taking measurements under reduced or low acceleration conditions, but this will adversely increase the operation time of each action, thereby reducing productivity, because each workpiece or machining step requires more time.

[0010] Other methods known in the field of coordinate machine operation attempt to avoid deflection, vibration, and / or oscillation caused by machine acceleration through a technique called input shaping. This technique controls the adjustment variables (force or current) of the propulsion motor, thereby bypassing some mechanical resonances and avoiding the excitation of known resonant frequencies determined by calculation or calibration.

[0011] It is also known to actively suppress oscillations by driving a corresponding manipulated variable at the output of an actuator control, or by using an additional controllable actuator attached to one of the structural components of the machine. Examples of such actuators that apply a controllable force to machine parts to forcibly suppress oscillations or vibrations are piezoelectric or pneumatic actuators. However, such additional actuation requires an additional force and may itself become a source of vibration and error.

[0012] Furthermore, in order to handle the aforementioned errors, especially dynamic errors, using known methods, it is usually necessary to establish and define a complex model of the coordinate machine, which enables the description of the positioning behavior, particularly the kinematic chain, based on this model.

[0013] Therefore, although there are known methods in the field of coordinate measuring machines to reduce errors associated with machine vibration or oscillation, these known methods may not be sufficient to meet the ever-increasing high-precision requirements of coordinate measuring machines, and as mentioned above, they have some drawbacks, especially the high cost, because they require specific additional hardware or software, or can only handle certain (especially predetermined) frequencies. Summary of the Invention

[0014] Therefore, the object of the present invention is to improve coordinate measurement and / or machine manipulation.

[0015] Another objective is to provide a coordinate measurement and / or manipulation machine with improved coordinate accuracy.

[0016] Another objective is to provide a coordinate measurement and / or manipulation mechanism that reduces or eliminates dynamic errors.

[0017] These objectives are achieved by implementing the features in the main aspects. Further developments of the invention in alternative or advantageous ways are described in other aspects.

[0018] Therefore, the present invention relates to an adjustable damping unit adapted for integration into a kinematic chain, for example, into the end piece of a kinematic chain of a machine designed for coordinate measurement and / or coordinate manipulation of a workpiece, to provide locally adaptive damping for varying oscillations of the measuring and / or manipulating tools connected to the end piece of the kinematic chain during machine operation. As previously stated, the term "tool" should be interpreted broadly to include non-machining measuring instruments, such as sensor heads or probes.

[0019] The adjustable damping unit includes at least one adjustable mechanical damping element whose damping characteristics can be dynamically adjusted based on actual sensor data of the position and / or motion of the kinematic chain.

[0020] Preferably, the energy dissipation properties, elastic properties, and / or inertial properties of the adjustable damping unit are adjustable. Therefore, for example, the energy conversion characteristics or capability for transforming the kinetic energy / movement (vibration) energy of the kinematic chain can be dynamically changed based on the actual sensor data of the kinematic chain.

[0021] In some implementations, the damping element includes an electromagnet designed to well-defined adjust the damping magnetic field. That is, a controllable magnetic field can be provided that can be altered in a known manner based on the sensing properties of the kinematic chain, thereby achieving damping based on the magnetic force between the magnetic bodies.

[0022] Alternatively, this controllable electromagnet is designed to make a precisely defined change to the induction of damped eddy currents based on sensor data from the kinematic chain.

[0023] Alternatively, the damping element comprises a fluid with a well-defined, adjustable viscosity, optionally an electrorheological fluid or a magnetorheological fluid. In this case, the controllable electromagnet is designed to precisely regulate the viscosity of the fluid.

[0024] In some implementations, the damping unit is designed for multi-axis adaptive damping, i.e., damping for more than one axis of movement.

[0025] The present invention also relates to a measuring and / or machining coordinate machine designed for coordinate measurement and / or coordinate manipulation of a workpiece, the machine having a kinematic chain whose end member is designed to receive measuring and / or manipulating tools. The machine includes the claimed adjustable damping unit. The damping unit is integrated into the kinematic chain (here, "in..." also includes arrangements where the damping unit is located outside the kinematic chain). The machine also includes a logic controller configured to receive and process actual position and / or motion sensor data of the kinematic chain to dynamically adjust the adjustable damping characteristics of the damping unit based on the actual sensor data.

[0026] Alternatively, the adjustable damping unit is designed to dynamically adjust the eigenmode of the kinematic chain based on the actual position and / or motion sensor data.

[0027] Optionally, the actual sensor data may be provided by at least one accelerometer of the machine, such as a MEMS accelerometer, located at the end piece and / or tool of the machine. Alternatively, the accelerometer may be an integral part of an inertial measurement unit (IMU) located at the end piece and / or tool.

[0028] As an alternative, the actual sensor data considered in the damping adjustment can be provided by at least one position encoder integrated in the kinematic chain, such as a rotary encoder at the joint of the robot arm of the machine.

[0029] In some embodiments of the machine, the kinematic chain includes multiple rotary joints connecting multiple links, wherein each rotary joint includes at least one drive unit comprising a motor and at least one position encoder that determines at least one angle and generates angle data. In these embodiments, the logic controller is configured to control the motor of each drive unit to drive an end piece relative to the machine's base, thereby approaching a measurement and / or machining point on the workpiece; receive angle data; and determine at least one spatial coordinate of that point based on the angle data.

[0030] The present invention also relates to a method for adaptively damping the changing oscillations of a coordinate measuring and / or manipulating tool connected to the end of the motion chain of a coordinate machine designed for coordinate measuring and / or coordinate manipulating a workpiece, particularly the claimed measuring and / or machining machine.

[0031] The method includes sensing the actual position and / or motion characteristics of the kinematic chain during machine operation, and dynamically adjusting the damping characteristics of at least one adjustable mechanical damping element integrated into the end effector of the machine, specifically in the form of a damping unit to be protected, based on the sensed actual position and / or motion characteristics. Thus, real-time adjustments are made to determined oscillation variations.

[0032] Optionally, the adjustable damping characteristic is characterized by at least one of an elastic parameter, an eddy current or inductive parameter, or a viscosity parameter.

[0033] The present invention also relates to a computer program product, preferably for use in the logic controller of the claimed coordinate machine, the computer program product having computer-executable instructions for automatically executing the steps of the claimed method.

[0034] The advantage of this invention lies in providing a coordinate machine for object measurement and / or machining, and a damping unit for such a coordinate machine that enables adjustments to the end-piece or payload of the machine based on the actual oscillations sensed or detected by the machine. Specifically, the damping parameters can be varied in real time, thereby customizing the machine's inherent modes or vibration behavior, particularly its ability to "absorb" the kinetic energy of any unintended vibrations at the end of the machine's kinematic chain. As a result, vibration damping that matches or is "tailor-made" to the actual or current "site" sensed and damped vibrations is provided.

[0035] Advantageously, various physical principles have been proposed to achieve damping, with the magnetic effect being the preferred application. This can be done directly in the form of magnetic force or indirectly as a tool to manipulate the damping properties of materials, especially by changing viscosity as a particularly advantageous damping parameter. Attached Figure Description

[0036] The systems, methods, and arrangements according to the invention will be described or explained in more detail below by way of example, with reference to the schematic examples shown in the accompanying drawings. The schematic diagrams in the drawings are not drawn to scale. Where appropriate, the same reference numerals are used for the same features or features having similar functions. Different indices of the reference numerals are used to distinguish different embodiments of the same or equivalent features exemplarily shown. The term "substantially" is used herein to describe the fact that a value, arrangement, or feature does not need to be 100% precise and may have slight deviations, but still within the scope of the invention. Specifically,

[0037] Figure 1 An exemplary embodiment of a coordinate machine with an adaptive damping unit according to the present invention is shown;

[0038] Figure 2a , Figure 2bA schematic diagram of a first exemplary embodiment of the adjustable damping unit is shown;

[0039] Figure 3a , Figure 3b A schematic diagram of another exemplary embodiment of the adjustable damping unit is shown;

[0040] Figure 4 Another exemplary embodiment of the adjustable damping unit is schematically illustrated; and

[0041] Figure 5 Another exemplary embodiment of the adjustable damping unit is illustrated schematically. Detailed Implementation

[0042] Figure 1 An exemplary embodiment of the coordinate machine according to the present invention is illustrated in an illustrative and simplified manner. This exemplary machine may be embodied as a coordinate measuring machine (CMM), but it should be clearly noted that all teachings, features and disclosures are not limited to coordinate measuring machines, but are equally applicable to other coordinate machines of this type, particularly coordinate machining machines, such as coordinate computer numerical control (CNC) machine tools.

[0043] Machine 1 is configured to determine the spatial coordinates of points on an object or workpiece O. It includes (in this example, a cascaded) robotic kinematic chain structure that movably connects a measuring or machining tool (hereinafter also referred to as payload 4) to a base 17. Other embodiments of measuring kinematic chains and other measuring machine structures are also known in the art, enabling payload 4 to move in a coordinate space or system to approach the object O therein in a fully deterministic manner. The payload 4 may be, for example, a probe or sensor head or a machining head, or a combination thereof. In this example, the machine structure includes a robotic arm with three rotary joints 13, 14, 15 and three links 10, 11, 12. Rotary joints 13 to 15 movably connect links 10 to 12 to each other and are connected to the machine's base 17.

[0044] like Figure 1 As shown, the first rotary joint 13 provides the first link 10 with mobility relative to the base 17 about a first rotation axis R1 (and in this example, also about a second rotation axis R2). The second rotary joint 14 provides the second link 11 with mobility relative to the first link 10 about a third rotation axis R3. The third rotary joint 15 provides the third link 12 with mobility relative to the second link 11 about a fourth rotation axis R4 and a fifth rotation axis R5. In a particular embodiment, the first rotation axis R1 and the second rotation axis R2 are orthogonally arranged, and the fourth rotation axis R4 and the fifth rotation axis R5 are also orthogonally arranged.

[0045] Of course, the metering robot arm of Machine 1 may contain fewer or more rotary joints than those shown in the figure to allow movement about, for example, more than five axes. In particular, any additional rotary joints may allow movement about one or more rotational axes. Thus, for example, a fourth rotary joint may provide mobility about a sixth and seventh rotational axis (not shown in the figure) for additional links.

[0046] As shown in the figure, the tool or payload 4 can be connected to the third and final link 12, which is referred to as the end member of the kinetic chain. The tool 4 can be connected or mounted (and thus replaceable) by means of a connecting element, or alternatively, the head 4 can be an integral part of the end member 12.

[0047] Each of joints 13 to 15 includes an actuator (e.g., an electric motor) for moving a connected component relative to another component; and a measuring unit equipped with sensors, such as angle encoders 13a, 14a, 15a, for determining one or more angles between the driven connected components. These rotary encoders 13a to 15a are preferably integral parts of the rotary joints 13 to 15. The control and evaluation unit 16 of machine 1 includes a logic controller and is configured to receive angle data related to the measured angles from the measuring units 13a to 15a to control the actuator to drive the load 4 at the end member 12 relative to the base 17, thereby approaching a measuring or manipulating point on the object O, and to determine the spatial coordinates of that point based on the angle data and, if applicable, known dimensional data of the tool 4, wherein these data can be defined using a calibration process. Figure 1 In this configuration, the control unit 16 is located in the base 17. However, it can also be located in other components of the machine 1, or as an external device.

[0048] The control and evaluation processor 16 of machine 1 is also connected to the damping unit 2 and the sensor 3, both of which are integrated into the kinematic chain, in this example, as shown, into the end piece 12 of machine 1. In principle, the damping unit 2 and the sensor 3 can be incorporated into one or more components of the kinematic chain, or attached to the outside of the kinematic chain, particularly applicable when adding the damping device of the present invention as an upgrade to a conventional machine 1 known in the prior art.

[0049] Using position encoders (such as one or more of the angle encoders 13a, 14a, 15a described above) as sensors at joints 13 to 15, the actual motion or position data (such as acceleration, velocity / rate, or pose) of the kinematic chain are sensed and evaluated by computer 16 to achieve instantaneous responsive damping control as described below.

[0050] As exemplary Figure 1As shown, the sensor 3, used to sense motion or position data of the kinematic chain, can also be placed close to the tool 4, for example, as close as structurally possible, such as directly at the mounting point or connection interface. This sensor 3 can also be integrated into the payload 4 itself, which includes a data interface for transmitting sensor data to the controller 16. Sensor data transmission can be wired or wireless (therefore, the logic controller 16 and the sensor 3 can also be viewed as interconnecting components of the damping unit 2, which has damping elements that can be controlled by the logic controller 16 in response to data acquired by the sensor 3). In this case, the sensor 3 is designed to sense motion, such as acceleration, at the end of the machine's kinematic chain based on its position (e.g., at the end piece 12 (as shown) or at the tool 4 attached to or integrated into the end piece 12).

[0051] A preferred example of such a motion sensor 3 is an accelerometer or inertial measurement unit (IMU), which can measure not only acceleration but also angular rate and selectively magnetic fields. Sensor 3 can be implemented as a single-angle sensor or a multi-axis sensor (e.g., a triaxial accelerometer). Sensor 3 can be implemented as a microelectromechanical device (e.g., a MEMS accelerometer). Using sensor 3, vibrations or oscillations at the end of the motion chain of machine 1 can be determined.

[0052] As previously described, the sensed actual position or motion data of the kinematic chain is transmitted to the controller 16, where it is evaluated and used as the basis for control to adjust the damping unit 2 accordingly. In other words, the damping unit 2 is adjustable, meaning its damping characteristics are not constant or fixed, but can be changed and adjusted, and this adjustment is controlled by position or motion information collected using sensors integrated at the various links of the machine (e.g., exemplary accelerometer 3 and / or position encoders 13a, 14a, 15a).

[0053] More specifically, the energy dissipation capacity / characteristics, elasticity, or inertial characteristics of the adjustable damping unit 2 are dynamically adjustable. This adaptability based on actual sensing data of the kinematic chain can be provided by the variable elasticity, sensitivity, inertia, or viscosity of the damping unit 2.

[0054] For example, by adjusting the adjustable damping unit 2, the frequency response or response spectrum or curve of the machine motion chain can be adjusted as an immediate or direct response to actual sensed motion data, such as for the frequency and / or amplitude of the response.

[0055] In addition to actual sensor data, pre-known data, such as calibration data or characteristic or specific data of tool 4, can be considered. For example, in the case of a machine 1 designed to mount different tools 4, to more specifically adapt to each different specific tool 4, the weight or size of which may cause different vibration behaviors of the end piece 12. Therefore, damping parameters (which can be parameters adjusted in real time, or another damping parameter of the adjusted damping unit 2 or another damping unit) can be pre-selected or pre-adjusted, for example, by software or hardware adjustment. For example, in an embodiment with multiple damping units 2 or damping elements, pre-selection can be made among them. Relevant tool data can be automatically transmitted to controller 16, for example, via the ID chip of tool 4, which stores these relevant tool specifications. However, the consideration of any such additional data is not mandatory, and adaptive damping can be based solely on actual motion or position sensor data, such as data sensed at or near actual locations at risk of disturbance or oscillation.

[0056] Therefore, the damping at the end of the kinematic chain can be adapted to the actual movement / position characteristics detected at that end by sensors (e.g., sensor 3 and / or encoders 13a to 15a). For example, motion sensor 3 is used to sense the actual oscillations of end piece 12 or tool 4. The oscillation damping of the adjustable damping unit 2 is adapted to the current oscillation state determined by the actual movement and / or position sensor data of at least one of sensors 3, 13a to 15a, making it possible to formulate a real-time, in-situ target damping. The logic controller 16 dynamically adjusts one or more damping parameters of the damping unit 2 based on the data from sensors 3, 13a to 15a, in order to minimize or eliminate the amplitude of oscillations locally located at end piece 12 (and thus at a specific point in the kinematic chain) in a precise manner in terms of position and time. In other words, the damping unit 2 is arranged and controlled to dynamically reduce or eliminate (variing) vibrations or oscillations specifically, precisely (and possibly only) at end piece 12 or tool 4.

[0057] Due to the proposed adaptive damping, any actual undesirable oscillations—particularly those originating from external environmental vibrations or imperfect internal actuators (whose vibrations are typically amplified by the robot's mechanical structure)—can be locally and dynamically reduced or eliminated. These oscillations would otherwise degrade the accuracy of the position determination of the end effector 12 or the payload / tool ​​4, thereby reducing the metrological performance of the machine 1. Sensing and specifically damping these oscillations at their actual effective location and time using sensed motion or position data or oscillation data is particularly advantageous because the local oscillations or vibration spectrum at the end effector 12 not only vary with environmental changes, but the robot 1's natural frequencies typically change dynamically during operation, depending on the kinematics and the position of the end effector 12 and / or the tool 4.

[0058] This adjustable damping unit 2 can be designed to dampen movement or degrees of freedom (DoF) relative to one or more axes of motion, or it can contain multiple adaptive damping elements. Furthermore, the machine 1 can use more than one exemplary motion sensor 3 or damper 2, and as an alternative, the adjustable damping unit 2 can contain fixed or constant damping elements or units (for damping the same or other axes of motion, or for different damping points in the kinematic chain) or combinations thereof. As previously mentioned, adaptive damping can employ different physical principles. For example, an inertial element (such as a flywheel or gyroscope) whose inertia and consequent damping characteristics can be adjusted. This variable inertial element can, for example, be implemented as a retractable flywheel, i.e., having a rotational mass at a controllable distance to its axis of rotation. If necessary, a standard mechanism (e.g., a rack and pinion mechanism) can be used to achieve the conversion between rotational and linear motion. Other preferred examples of the adjustable damping unit 2 will be described in more detail in the context of the following figures.

[0059] Figure 2a , Figure 2b A first exemplary embodiment of the adaptive damping unit 2a is shown, wherein Figure 2a This is a 2D schematic diagram of the cross-section of element 2a. Figure 2b This is a schematic 3D view of unit 2a.

[0060] This exemplary embodiment utilizes an electromagnet to change the elastic modulus or stiffness, which can be referred to as an electromagnetic spring. Between the mechanical input link 22 and the output link 23 integrated into the mechanical frame structure 21, magnets 20e and 20p (three in this example) are arranged, and the magnetic field between them substantially defines the elasticity of the damper 2a. Since at least one magnet is implemented as an electromagnet, the magnetic field and the elasticity as a damping parameter are variable. In this example, the two outer magnets 20e coupled to the input link 22 are electromagnets, while the inner magnet 20p coupled to the output link 23 is a permanent magnet.

[0061] The mechanical frame 21 of the exemplary damping unit 2a also includes a mechanically permanent flexible element 21s connecting the input link 22 and the output link 23 to provide structural integrity and define a minimum stiffness limit, thereby limiting the limits of the adaptive damping parameters in the absence of current flowing through the electromagnet 20e. This stiffness limit limitation by means of a constant element such as the flexible element 21s is not limited to this exemplary embodiment and can be applied to other embodiments, such as those described below. Links 22 and 23 can be pushed apart by two additional (auxiliary) permanent magnets to prevent buckling of the flexible element 21s.

[0062] The current supplied to the two outer magnets 20e can be controlled by the aforementioned logic controller to adjust their magnetic fields, thereby modifying the damping characteristics at the output terminal 23. This allows for a change in the magnetic field strength. The stiffness of the device 2a is proportional to the current flowing through the two electromagnets 20e (plus a small offset caused by the flexible element 21s). This modification can also include completely shutting off the electromagnets, for example, when the aforementioned sensor at the payload does not detect oscillations or does not detect significant oscillations, or when the frequency of the oscillation to be damped is covered by the damping unit 2a, which is in a passively off state.

[0063] Preferably, the two electromagnets 20e are controlled together or in a unified manner, but in any embodiment where multiple electromagnets 20e are arranged, each electromagnet 20e or a subgroup of electromagnets can also be controlled individually. The latter allows not only changes in the magnetic field strength in a general manner, but also changes in the range or shape of the overall magnetic field, and consequently, adjustments to the elasticity, for example, to individually adjust the damping for a single or different degree of freedom. In this case, for example, a “3D” arrangement of spatially distributed magnets can be installed to provide a multidirectional damping unit (instead of the so-called linear “2D” arrangement providing unidirectional variable elastic elements as shown). Of course, several unidirectional elements can also be stacked together to form a multidirectional damping unit 2a.

[0064] Figure 3a , Figure 3b A second exemplary embodiment of the adaptive damping unit 2b is shown, wherein Figure 3a This is a 2D schematic diagram of the cross-section of element 2b. Figure 3b This is a schematic 3D view of unit 2b.

[0065] This exemplary damping unit 2b utilizes a viscosity-adjustable fluid 25 as a variable damping parameter. In this example, the fluid 25 is a magnetorheological fluid, i.e., a fluid whose mechanical properties are controllable in the presence of an external magnetic field, with property changes typically ranging from several orders of magnitude over milliseconds. This ability to alter shear strength or viscosity based on the applied magnetic field is used to change the damping characteristics of the damping unit 2b. Other variable fluids 25 with controllable physical properties (e.g., electrorheological fluids), or other physical principles for controlled viscosity changes (e.g., temperature changes), can also be used to adjust the damping characteristics of the unit 2b.

[0066] Therefore, by controlling the magnetic field to which the magnetorheological fluid 25 can be exposed in response to sensing data from the kinematic chain (e.g., using the logic controller of the aforementioned coordinate machine) as a variable, the damping properties of the damping unit 2b can be adjusted. The viscosity of the damping device 2b, and consequently its damping coefficient, can be controlled and set to be proportional to the current flowing through the electromagnet 20e. Thus, a variable viscosity is used as a damping parameter, which can be adjusted according to the actual current sensing properties of the coordinate machine's kinematic chain, thereby achieving real-time adaptive oscillation damping.

[0067] In this example, fluid 25 (e.g., in the form of a dispersion of magnetic soft particles in a carrier fluid) is provided within a (sealed) container 24 attached to a frame structure 21 located between input link 22 and output link 23. A portion of container 24 is rigidly connected to input link 22, another portion is rigidly connected to output link 23, and fluid 25 is contained between the two. Container 24 can be exposed to a variable magnetic field via (in this example, two) electromagnets 20e (e.g., arranged on opposite sides). Electromagnets 20e are coupled to input link 22, and container 24 is coupled to both input link 22 and output link 23.

[0068] When all electromagnets 20e are disabled (i.e., no magnetic field is applied), and the fluid 25 is in a high-viscosity state, the container structure allows deformation (e.g., deformation caused by vibration) without generating significant resistance (as previously stated, such as...). Figure 2a , Figure 2b As shown in the example, one or more fixed springs can also be applied here to limit the upper limit of stiffness. However, with the electromagnet 20e activated, the fluid 25 is in a low-viscosity state due to the applied magnetic field, and the container structure resists deformation in any direction. This resistance is positively correlated with the deformation rate (especially the oscillation frequency) and the magnetic field strength, which is controlled based on the real-time sensor data of the local motion. Therefore, in this case, an omnidirectional adjustable damping unit 2b is provided.

[0069] For example, container 24 includes two sets of rigid helical columns 24h (such as...) Figure 3a As shown), one set is located on the input side and the other set is located on the output side, which can enhance the damping performance. For example, two arrays or rigid screws 24h are coupled (e.g., near the corresponding connecting rods 22, 23) to the opposite walls of the container 24 and immersed in the fluid 25.

[0070] Figure 4 A third exemplary embodiment of the adaptive damping unit 2c is illustrated using a 2D cross-sectional schematic diagram.

[0071] and Figure 3a , Figure 3bSimilar to the example described, the damping characteristics can be adjusted by controlled viscosity changes. A magnetorheological fluid 25 is also used here to adjust the viscosity, thereby modulating its energy dissipation properties. In the example where two electromagnets 20e are located on opposite sides of the fluid 25, this energy dissipation property can be altered using electromagnets 20e mounted near the fluid 25. Furthermore, as mentioned above, the magnetic field control provided by the electromagnets 20e depends on sensor data, making the mechanical damping ratio of output 23 to input 22 variable as a response to motion data sensed at the end of the coordinate machine's motion chain.

[0072] An exemplary implementation of this variable viscosity concept includes a container 24 located at a frame 21 between the input end 22 and the output end 23, the container 24 having a flexible internal structure 26 resembling a lattice (e.g., a diamond-like lattice) or a sponge made of a rubbery polymer. For actual 3D variable damping, fluid 25 can flow through the entire lattice or sponge, or in other words, through the entire volume of container 24, but due to the presence of the lattice-like structure, the flow of fluid is not linear.

[0073] Additionally, adjustments can be achieved through adaptive flow—for example, some coarse adjustment or pre-adjustment, as container 24 contains multiple chambers that can be connected and disconnected, for example, by controllable baffles. Furthermore, the magnetic field can be provided by a series of electromagnets, for example, arranged in a row along one side of container 24, with subgroups of these electromagnets selectively activated or deactivated as described above to achieve coarse or minimal damping adjustments, and can be further fine-tuned by current control of the active magnet 20e.

[0074] Figure 5 A fourth exemplary embodiment of the adaptive damping unit 2d is also shown using a 2D cross-sectional schematic diagram.

[0075] In this example, the damping unit 2d is an inductive damping unit that utilizes adjustable eddy current induction to control the removal of vibrational energy from the tip of the coordinate machine's kinematic chain. In an exemplary implementation, a controllable electromagnet 20e located on one side of the unit's frame 21 at the input terminal 22 is arranged inside a conductive element 27 located on one side of the output terminal 23.

[0076] Therefore, in this design, for example, the electromagnet 20e is connected to the input link 22, while the conductive tube 27 surrounding the electromagnet 20e is connected to the output link 23. The eddy currents induced in the tube by the motion of the electromagnet 20e are positively correlated with the velocity of the electromagnet 20e.

[0077] Similarly, the strength of the magnetic field provided by one or more magnets 20e is controlled by motion or position data of the kinematic chain (e.g., sensed by an accelerometer near the tip of a coordinate machine, as described above), thereby controlling the strength of the eddy currents induced in the conductive counterpart 27.

[0078] The tubular implementation shown in the figure can be considered as a unidirectional variable viscous damping element. For multidirectional damping, multiple such elements 2d can be integrated in a coordinate machine. Moreover, in addition to the tube 27, other structures can be used; for example, a structured extension plate can be used as a 2D region to achieve multidirectional damping. The structure of the conductive counterpart can also be used to change the damping; for example, different regions can be electrically connected or disconnected to control the limitation of eddy currents on the "receiving" side, for example, for some kind of pre-tuning. As another example, materials or structures with controllable and adjustable conductivity can also be used.

[0079] More generally, the adjustment function or damping capability can be achieved not only on the "transmitter" side (electromagnet 20e in this example) but also on the "receiver" side (conductor 27 in this example), i.e., an adjustable and controllable receiver.

[0080] Those skilled in the art will understand that the details shown and explained herein for different embodiments can also be combined with details of other embodiments and other permutations in the sense of the present invention.

Claims

1. An adjustable damping unit (2, 2a-2d) designed for integration into the kinematics of a measuring and / or machining machine (1), the measuring and / or machining machine (1) being designed for coordinate measurement and / or coordinate manipulation of a workpiece (O), wherein, The adjustable damping unit (2, 2a-2d) is designed to adaptively dampen the changing oscillations of the measuring and / or manipulating tool (4) connected to the end piece (12) of the kinematic chain during the operation of the measuring and / or processing machine (1), and includes at least one adjustable mechanical damping element whose damping characteristics can be dynamically adjusted according to the actual position of the kinematic chain and / or motion sensor data.

2. The adjustable damping unit (2, 2a-2d) according to claim 1. Its features are, The adjustable mechanical damping element is designed to dynamically adjust at least one of the energy dissipation characteristics, elastic characteristics, and inertial characteristics of the adjustable damping unit (2, 2a-2d) based on actual sensor data of the kinematic chain.

3. The adjustable damping unit (2, 2a-2d) according to claim 1 or 2. Its features are, The damping element includes an electromagnet (20e).

4. The adjustable damping unit (2, 2a-2d) according to claim 3. Its features are, The electromagnet (20e) is designed to precisely define the adjustment of the damping magnetic field.

5. The adjustable damping unit (2, 2a-2d) according to claim 3 or 4. Its features are, The electromagnet (20e) is designed to make a well-defined change to the induction of damped eddy currents.

6. The adjustable damping unit (2, 2a-2d) according to any one of the preceding claims. Its features are, The damping element includes a fluid (25) having a well-defined adjustable viscosity.

7. The adjustable damping unit (2, 2a-2d) according to any one of claims 3 to 5 and claim 6. Its features are, The fluid (25) is a magnetorheological fluid or an electrorheological fluid, and the electromagnet (20e) is designed to precisely regulate the viscosity of the fluid.

8. A measuring and / or machining machine (1) designed for coordinate measurement and / or coordinate manipulation of a workpiece (O), the machine (1) having a kinematic chain having an end piece designed to receive a measuring and / or manipulating tool (4), Its features are, The machine (1) includes ● The adjustable damping unit (2, 2a-2d) according to claim 1, wherein the adjustable damping unit is integrated in the kinematic chain, and ● Logic controller (16), which is configured to receive and process actual position and / or motion sensor data of the kinematic chain to dynamically adjust the adjustable damping characteristics of the damping unit based on the actual position and / or motion sensor data.

9. The machine (1) according to claim 8. Its features are, The adjustable damping units (2, 2a-2d) are designed to dynamically adjust the inherent modes of the kinematic chain based on the actual position and / or motion sensor data.

10. The machine (1) according to claim 8 or 9. Its features are, The actual position and / or motion sensor data can be provided by at least one position encoder (13a, 14a, 15a) integrated in the motion chain.

11. The machine (1) according to claim 10. Its features are, The kinematic chain includes multiple rotary joints (13, 14, 15) connecting multiple links (10, 11, 12), wherein each rotary joint (13-15) includes ● At least one drive unit, said at least one drive unit including a motor, and ● The at least one position encoder (13a, 14a, 15a), which is designed to determine at least one angle and generate angle data. The logic controller (16) is configured to ● Control the motor of each drive unit to drive the end piece relative to the machine base to approach the measurement and / or machining point of the workpiece (O). ● Receive the angle data, and ● Determine at least one spatial coordinate of the point based on the angle data.

12. The machine (1) according to any one of claims 8 to 11. Its features are, The machine (1) includes an acceleration sensor (3) for providing actual sensor data, and in particular, the acceleration sensor (3) ● Located at the end piece (12) and / or the tool (4), and / or ● It is an integral part of the inertial measurement unit.

13. A method for adaptively damping the changing oscillations of a measuring and / or manipulating tool (4) of the end piece (12) of a kinematic chain connected to a measuring and / or machining machine (1), particularly the measuring and / or machining machine (1) according to claim 8, the measuring and / or machining machine being designed for coordinate measurement and / or coordinate manipulation of a workpiece (O), the method comprising, during operation of the measuring and / or machining machine (1) ● Sensing the actual position and / or motion properties of the kinematic chain, and ● Dynamically adjust the damping characteristics of at least one adjustable mechanical damping element integrated into the kinematic chain of the machine (1) according to the sensed actual position and / or motion characteristics, the adjustable mechanical damping element being particularly the adjustable mechanical damping element according to claim 1.

14. The method according to claim 13, Its features are, The damping characteristics are characterized by at least one of the following parameters: ● Elasticity, ● Inertia, ● Vortex, or ● Viscosity.

15. A computer program product, particularly a computer program product for a logic controller (16) of a measuring and / or processing machine (1) according to claim 8, the computer program product having computer-executable instructions for automatically performing the steps of the method according to claim 13.

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