Manipulator for variable positioning of movable element on measuring machine

Abstract

A manipulator for variable positioning of a movable element (42) on a measuring machine includes a stator (32) forming a manipulator base. The first coupling member (34) is rotatably held on the stator (32) via a first rotational joint (48). The second coupling member (36) is rotatably held on the stator (32) via a second rotational joint (54). The third coupling member (38) is rotatably held on the second coupling member (36) via a third rotational joint (62). The end effector (40) is rotatably held on the first coupling member (34) via a fourth rotational joint (66) and also rotatably held on the third coupling member (38) via a fifth rotational joint (68).

Description

Field of the Invention

[0001] The present invention relates to a manipulator for variable positioning of a movable element in or on a measuring machine. Such a manipulator can advantageously be used to move a tactile and / or optical measuring probe on a coordinate measuring machine into a desired orientation relative to a measurement object. Additionally, the manipulator described below can advantageously be used to move a light source or a deflection mirror in a measuring machine into a desired orientation. Background Art

[0002] DE 10 2020 114 673 B3 discloses a so-called spherical parallel manipulator for a coordinate measuring machine. Such coordinate measuring machines have been known for a long time. These coordinate measuring machines have a measuring head that moves relative to a measurement object in order to detect selected measurement points on the measurement object. Depending on the spatial position of the measuring head, the coordinates of the detected measurement points can be determined in a previously defined coordinate system. In a further step, based on the coordinates, the dimensions and / or geometric properties of the measurement object, such as the diameter of a hole or the length of an edge, can be determined. Such coordinate measuring machines are often used in the development and industrial manufacture of products to test whether the dimensions and / or geometric properties of the products correspond to the desired specifications.

[0003] In many cases, the measurement points on the measurement object are detected by touching the measurement object with a probe element of the measuring head. The probe element is usually a stylus with a free end that is designed as a ball. The measuring head carries the probe element, and as soon as the probe element touches the measurement object, the measuring head detects the deflection of the probe element relative to the measuring head. In this case, it is referred to as the tactile detection of the measurement point or as a tactile measuring head. There are also multiple measuring heads through which the measurement points on the measurement object are detected without touching, in particular by optical or capacitive means. It is also possible to determine the surface properties of the measurement object (such as the roughness and / or gloss level of the surface) or the spatial position of the measurement object as a whole in measuring machines in which the measuring head and / or another element required for the measurement must be moved.

[0004] The parallel manipulator described in DE 10 2020 114 673 B3 has a base platform and a rotor plate which is movable relative to the base platform and bears a stylus, and also has a spherical parallel kinematic system with three articulated arms. Each of the three articulated arms is rotatably fastened at one end to the base platform and at the other end to the rotor plate, and thus they couple the rotor plate to the base platform. The base platform also bears three rotary drives, each of which is capable of rotating the corresponding articulated arm about a corresponding axis of rotation. By appropriate actuation of the rotary drives, the stylus can be pivoted relative to the base platform about three spatial axes. To increase the stiffness, this known parallel manipulator also has a ball-and-socket joint which is connected to the movable plate. A similar parallel manipulator is disclosed in DE 10 2019 115 630 B3.

[0005] DE 10 2019 211 063 B3 discloses another parallel manipulator which has three articulated arms and three rotary drives for guiding the laser beam of a distance measuring device to a retroreflector.

[0006] DE 10 2007 004 934 A1 discloses a test method for coordinate measuring machines and other positioning machines, in which the laser beam of a distance measuring device is guided to a retroreflector arranged on a machine part. The machine part is moved to different positions relative to the distance measuring device. Based on a plurality of distance measurement results, the distances between the positions can be determined and compared with the distances calculated based on the machine coordinates.

[0007] Furthermore, for many years, coordinate measuring machines have used known serial kinematic systems in the form of rotary swivel joints in order to move the stylus into the desired orientation. For example, reference is made to DE 37 40 070 A1 and WO 2016 / 015775A1. The disadvantage of the rotary swivel joint is the divergence of the mass or the mass moment of inertia relative to the respective axes of movement. As a result of the serial arrangement of the axes of movement, these individual rotary joints must carry and move different masses. Therefore, there are different requirements for each axis of rotation, which makes it difficult to ensure the constant accuracy requirements for each direction of movement. In addition, due to the serial arrangement of the axes of movement, the rotary swivel joint requires a relatively large movement clearance in the measuring volume of the measuring machine.

[0008] In contrast, the known parallel manipulator has the advantage that the axes of rotation each carry the same mass. Additionally, the parallel manipulator can have a very compact design. However, the mechanical construction is relatively complex, and the actuation of these three parallel rotary drives is also unnecessarily complex for many simple measuring tasks. Summary of the Invention

[0009] Against this background, the object of the present invention is to provide a manipulator for the variable positioning of a movable element in or on a measuring machine, which on the one hand avoids the disadvantages of series-rotating swivel joints and on the other hand has a low complexity. In addition, a simpler actuation of the orientation of the movable element is required.

[0010] According to one aspect of the invention, this object is achieved by a manipulator of the type described at the beginning, which comprises: a stator, which forms the manipulator base; a first coupling member, a second coupling member and a third coupling member; a first rotary joint, a second rotary joint, a third rotary joint, a fourth rotary joint and a fifth rotary joint; and an end effector, wherein the first coupling member is rotatably held on the stator via the first rotary joint, wherein the second coupling member is rotatably held on the stator via the second rotary joint, wherein the third coupling member is rotatably held on the second coupling member via the third rotary joint, wherein the end effector is rotatably held on the first coupling member via the fourth rotary joint and is also rotatably held on the third coupling member via the fifth rotary joint.

[0011] The novel manipulator implements a parallel kinematics, wherein, compared to the prior art described at the beginning, the end effector is rotatably held only on two rotary joints, which provide mutually different axes of rotation. The end effector is the part of the manipulator that carries or contains the measuring element to be moved via the manipulator. The end effector is held by the first coupling member and the third coupling member, wherein the fourth rotary joint allows the end effector to rotate relative to the first coupling member, and wherein the fifth rotary joint allows the end effector to rotate relative to the third coupling member. Compared to the prior art with three articulated arms described at the beginning, the end effector is not directly connected to the second coupling member here. Instead, the second coupling member couples the third coupling member to the stator. As a result, the third coupling member is connected to the stator indirectly here, i.e. via the second coupling member. Correspondingly, the novel manipulator contains a series arrangement of axes of rotation from the stator to the end effector via the second coupling member and the third coupling member, while the first coupling member couples the end effector to the stator in parallel.

[0012] Due to the parallel arrangement of the first coupling member relative to the second and third coupling members, the novel manipulator can be made very light and compact and requires minimal moving clearances. In addition, the manipulator allows for a small mass divergence with respect to the movement axis of the end effector. As a result, the end effector can be positioned very quickly and accurately with the aid of the novel manipulator. Thus, the novel manipulator benefits from the design advantages provided by parallel kinematics. However, the novel manipulator is simpler and lighter than the prior art parallel manipulators described at the beginning. Instead of six rotary joints or even nine rotary joints (if the "inner" rotary joints of the three articulated arms are considered), the novel manipulator has only five rotary joints. The end effector can pivot about two resulting pivot axes, which simplifies actuation. The two resulting pivot axes and the associated two degrees of freedom are fully sufficient for many uses in metrology.

[0013] Therefore, the above object is fully achieved.

[0014] It should be noted that the manipulator base forms a stationary part relative to the coupling members and the end effector. The end effector can pivot relative to the manipulator base about two resulting pivot axes. Nevertheless, in a preferred exemplary embodiment, the manipulator base can be arranged on the movable part of a coordinate measuring machine, in particular on the quill shaft or the horizontal arm of a conventional coordinate measuring machine.

[0015] In a preferred embodiment, the first rotary joint defines a first rotary axis, the second rotary joint defines a second rotary axis, and the first rotary axis and the second rotary axis intersect at a common axis intersection point.

[0016] Thus, the first rotary axis and the second rotary axis span a plane. The resulting pivot axis of the end effector lies in this plane. Preferably, all five rotary axes of the five rotary joints intersect at this one axis intersection point. This embodiment facilitates determining the resulting pivot position of the end effector based on the rotation angles of the coupling members, particularly in the preferred case where all five rotary axes intersect at the axis intersection point. In this case, the axis intersection point forms a tool center point (TCP) that can be clearly and easily defined, i.e., the point about which the end effector rotates.

[0017] In a preferred exemplary embodiment, the angle between the first axis of rotation and the second axis of rotation can be 90°. Similarly, the angle between the second axis of rotation and the third axis of rotation, the angle between the first axis of rotation and the fifth axis of rotation, and the angle between the fourth axis of rotation and the fifth axis of rotation can each be 90° in each case. In some preferred exemplary embodiments, the angles are thus the same. However, it is also possible that the angles are not equal to 90° and are different from each other. For example, the angle between the axes of rotation on the third coupling member can be 45° or 60°. Other angles are also possible.

[0018] In another embodiment, the fourth rotary joint has two support points, and the end effector is rotatably arranged between the two support points.

[0019] In this embodiment, both sides of the end effector are supported, which helps to position the end effector more stably and accurately.

[0020] In another embodiment, the first rotary joint is a one-sidedly mounted rotary joint. In some preferred exemplary embodiments, one or more of the other rotary joints are also one-sidedly mounted. In an exemplary embodiment, the first rotary joint, the second rotary joint, the third rotary joint, and the fifth rotary joint are one-sidedly supported, while the fourth rotary joint is two-sidedly supported.

[0021] This embodiment realizes a particularly light and compact manipulator, which helps to achieve high dynamic performance of the movement of the end effector. Therefore, this embodiment is particularly advantageous for manipulators that are intended to allow the end effector to move quickly and / or are intended to have a minimal weight.

[0022] In another embodiment, the first rotary joint has two support points, and the first coupling member is arranged between the two support points. In some preferred exemplary embodiments, one or more of the other rotary joints are also two-sidedly supported. In an exemplary embodiment, the first rotary joint, the second rotary joint, the fourth rotary joint, and the fifth rotary joint are all two-sidedly supported, while the third rotary joint is one-sidedly supported.

[0023] This embodiment realizes a very stable manipulator, which helps to achieve a high positioning accuracy of the movement of the end effector and a high load. However, also in this embodiment, the novel manipulator is simpler and lighter than the known parallel manipulators of the prior art described at the beginning.

[0024] In another embodiment, the stator surrounds the first coupling member and the end effector in an annular shape. In a preferred exemplary embodiment, the stator also surrounds the second coupling member and / or the third coupling member in an annular shape.

[0025] In the context of this embodiment, and also in the context of the following embodiments, the annular design includes a circular configuration, i.e., a configuration having a constant radius along a range angle, but also includes non-circular configurations, including configurations having non-curved portions. This embodiment achieves a particularly compact and stable configuration. In addition, compared to the plate-like solid bodies of the known type in the parallel manipulators of the prior art described at the beginning, the annular configuration of the stator achieves weight reduction.

[0026] In another embodiment, the first coupling member is designed in an annular shape. Preferably, the annular first coupling member is arranged concentrically with respect to the annular stator. In addition, in a preferred exemplary embodiment, the end effector can be designed in an annular shape and / or arranged concentrically with respect to the stator and / or the first coupling member. These embodiments together and individually contribute very advantageously to a compact and particularly stable configuration.

[0027] Alternatively, in other embodiments, the first coupling member can be of a partial annular shape, in particular a semi-circular shape, or a bracket shape or an arc shape. This embodiment achieves an even lighter construction and high dynamic performance for the positioning movement of the end effector.

[0028] In another embodiment, the second coupling member is designed in a partial annular shape.

[0029] In a preferred exemplary embodiment, the second coupling member is of a bracket shape, having a range angle between 60° and 120°, in particular having a range angle of 90°. Here, the range angle represents the angle between two straight lines extending from the respective endpoints of the bracket-shaped coupling member to the axis intersection point of the rotation axis. The range angle represents the bracket length equal to the arc measure on the circular arc. The coupling member can have a circular arc shape or a bracket shape that deviates from the circular arc of a constant radius to the axis intersection point. This embodiment achieves a particularly light configuration. In other exemplary embodiments, the second coupling member is of a bracket shape, having a range angle between 160° and 200°, in particular having a range angle of 180°. Thus, the second coupling member can advantageously be designed as a semi-ring, which achieves a very stable configuration. Similarly, in a preferred exemplary embodiment, the third coupling member can be of a partial annular shape, in particular a bracket or semi-ring shape. In a preferred exemplary embodiment, these rotary joints are all arranged in the non-curved portions of the stator and / or these coupling members.

[0030] In another embodiment, the first coupling member, the second coupling member, and / or the third coupling member are all designed as rigid one-piece brackets or rings.

[0031] This embodiment contributes to a high degree of rigidity and enables simple and cost-effective manufacturing.

[0032] In another embodiment, the manipulator further includes a first rotary drive and a second rotary drive, wherein the first rotary drive is designed to rotate the first coupling member relative to the stator, and wherein the second rotary drive is designed to rotate the second coupling member relative to the stator.

[0033] In this embodiment, the novel manipulator is active. The spatial position of the end effector can be automatically set via the control unit by means of the rotary drives, wherein the control unit actuates the two rotary drives synchronously. This enables, for example, advantageous scanning measurements of the measurement object along a predefined measurement trajectory.

[0034] In another embodiment, these rotary joints each have an associated angle measurement sensor, which is designed to determine the current rotational angular position of the respective rotary joint.

[0035] This embodiment facilitates the use of a conventional evaluation and control unit of a coordinate measuring machine to determine the respective position of the end effector. Alternatively or additionally, the current position of the end effector can be determined in another way, for example by means of an optical sensor system that irradiates a mirror surface on the end effector and detects position-dependent reflections.

[0036] It is also particularly advantageous to integrate the angle measurement sensors in the novel manipulator when the novel manipulator is of passive design (i.e., without electric rotary drives) and the rotary joints are lockable. Thus, in another embodiment, at least one of these rotary joints is lockable in order to prevent rotational movement.

[0037] This embodiment enables a very cost-effective and additionally very compact and lightweight configuration. In this embodiment, the desired position of the end effector can be manually adjusted, for example, after the lock has been released. Once the desired position of the end effector has been adjusted, the operator can activate the lock. Due to the lock, the end effector remains in the set position, and with the aid of the angle measurement sensor, this position can be determined and used very easily and accurately in the evaluation unit of the measuring machine.

[0038] In another embodiment, the end effector has a deflecting mirror.

[0039] This embodiment is particularly advantageous when the novel manipulator is used together with a laser-based distance measuring device, in particular a laser tracker. In some exemplary embodiments, the mirror normal is arranged at an angle of 90° to the first axis of rotation and at an angle of 45° to the second axis of rotation. However, other angles are also possible. In some preferred exemplary embodiments, the stator is connected to the laser source for co-rotation, and the beam of the laser source irradiates the deflecting mirror. Due to its light weight and compact design, the novel manipulator is advantageously suitable for this purpose.

[0040] In another embodiment, the end effector has a probe exchange interface that is designed to hold a measuring probe.

[0041] In a preferred exemplary embodiment, the probe exchange interface is designed to releasably hold commercially available probe tools (optical and / or tactile probe tools) on the end effector. This embodiment allows for the advantageous use of the novel manipulator to align such probe tools in a coordinate measuring machine. Particularly advantageously, the probe exchange interface can be designed to hold a stylus for tactile probing of measurement points on a measurement object.

[0042] In another embodiment, the manipulator also has a measuring machine exchange interface that is designed to optionally fasten the manipulator to a coordinate measuring machine.

[0043] In a preferred exemplary embodiment, the measuring machine exchange interface is designed to releasably hold the manipulator on the coordinate measuring machine, in particular on a sleeve shaft and / or on a measuring head having a stylus sensor that is designed to detect the deflection of the stylus relative to the measuring head. This embodiment allows for the simple use of the novel manipulator in place of a conventional rotary swivel joint, i.e., as an alternative to a conventional rotary swivel joint. In some preferred exemplary embodiments, the manipulator of this embodiment is configured to be passive. Thus, it allows for cost-effective alignment of the stylus or optical sensor by manual adjustment. In other exemplary embodiments, the manipulator of this embodiment is configured to be active and thus has two integrated rotary drives that are held downstream of the measuring machine exchange interface such that the rotary drives together with the stator and the coupling member can be fastened to the coordinate measuring machine in one step. Advantageously, the measuring machine exchange interface has electrical contacts that are configured to supply electrical energy from the coordinate measuring machine to the rotary drives.

[0044] In another embodiment, the end effector is also mounted in a spherical cap.

[0045] Mounting the end effector of the parallel kinematic system in a spherical cap bearing contributes to a particularly stable arrangement. In some exemplary embodiments in which the end effector has a deflecting mirror, the ball of the spherical cap bearing has a recess below the deflecting mirror. This recess enables a large adjustment range of the deflecting mirror without blocking the laser beam.

[0046] It should be understood that the above features, as well as the features yet to be explained below, can be used not only in the combinations cited accordingly, but also in other combinations or individually without departing from the scope of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Multiple exemplary embodiments of the invention are shown in the drawings and are explained in more detail in the following description. In the drawings:

[0048] Figure 1 An exemplary embodiment of a coordinate measuring machine in which the novel manipulator can be advantageously used is shown,

[0049] Figure 2 An exemplary embodiment of the novel manipulator having a laser for distance measurement is shown,

[0050] Figure 3 The manipulator with the end effector in another position is shown Figure 2 is shown,

[0051] Figure 4 Another exemplary embodiment of the novel manipulator with a tactile measuring head on the end effector and in a stable design is shown,

[0052] Figure 5 Another exemplary embodiment of the novel manipulator with an optical measuring head on the end effector and in a stable design is shown,

[0053] Figure 6 Another exemplary embodiment of the novel manipulator with a stylus on the end effector and in a lighter design is shown, and

[0054] Figure 7 Another exemplary embodiment of the novel manipulator having an additional support for the end effector is shown. DETAILED DESCRIPTION

[0055] In Figure 1In it, a coordinate measuring machine of an exemplary embodiment with a novel manipulator is generally designated by reference numeral 10. The coordinate measuring machine 10 has a base 12, on which a gantry 14 is arranged here. The gantry 14 has a cross beam, on which a slide 16 is arranged. The slide 16 carries a sleeve shaft 18. By means of a drive (not shown here), the gantry 14 can be moved relative to the base 12 in the longitudinal direction, which is designated as the Y-axis here. Similarly, the slide 16 can be moved along an orthogonal direction, which is designated as the X-axis here, and the sleeve shaft 18 can be moved along another orthogonal direction, which is designated as the Z-axis here. At the free end of the sleeve shaft 18, a measuring head 20 is fastened, so that the measuring head can thus move along three spatial axes X, Y, Z within the measuring volume. The measuring head 20 is designed to detect selected measuring points on a measuring object 22. In the exemplary embodiment shown here, the measuring head 20 has a stylus, which is held on the measuring head 20 by an exemplary embodiment of the novel manipulator. By means of the stylus, the selected measuring points on the measuring object 22 can be touched in a manner known per se. Using the position of the measuring head 20 in the measuring volume, the spatial coordinates of the detected measuring points can then be determined along the three spatial axes X, Y, Z. The spatial coordinates make it possible to determine the geometric and / or dimensional characteristics of the measuring object 22, such as the distance between two measuring points, the length of an edge or the diameter of a hole. Along the axes X, Y, Z, the coordinate measuring machine 10 respectively has suitable scales 22, 24, 26, by means of which the corresponding position of the measuring head 20 in the measuring volume can be determined.

[0056] Reference numeral 28 denotes an evaluation and control unit, which controls the movement of the measuring head 20 in the measuring volume and is designed to determine the spatial coordinates of the detected measuring points. The evaluation and control unit 28 can contain a drive controller for controlling an electric drive (not shown here) of the coordinate measuring machine 10, and furthermore contain a separate computer on which measurement software is executed, and the spatial coordinates are determined using this measurement software. The computer can contain a commercially available operating system, such as Microsoft Windows, Linux / Unix or MacOS, and the measurement software can be, for example, the measurement software CALYPSO of Carl Zeiss Industrial Metrology GmbH, Carl-Zeiss-Strasse 22, 73447 Oberkochen, Germany.

[0057] The coordinate measuring machine 10 with the portal 14 is an exemplary embodiment of a measuring machine in which the novel manipulator can be advantageously used. Here, the portal 14 together with the slide 16 and the sleeve shaft 18 forms a holding structure for the measuring head 20. In other exemplary embodiments, the holding structure can be designed in another way. For example, the holding structure can contain a robotic arm with one or more joints (not shown here), or the coordinate measuring machine can contain a moving column on which a movable horizontal arm is arranged. Additionally, the novel manipulator can be used together with a laser-based distance measuring device, as will be explained below with reference to Figure 2 and Figure 3 . For example, by such an exemplary embodiment, the method described in DE10 2007 004 934 A1 mentioned at the beginning can be implemented.

[0058] In Figure 2 and Figure 3 , a first exemplary embodiment of the novel manipulator with a laser for distance measurement is generally denoted by the reference numeral 30. The manipulator 30 contains a stator 32 (here designed in the form of a bracket in a partial ring shape), a first coupling member 34, a second coupling member 36, a third coupling member 38, and an end effector 40. The stator bracket 32 extends here over an arc length corresponding to approximately a quarter circle. Thus, the angular range is approximately 90° here. In other exemplary embodiments, the stator bracket 32 can have an L-shaped form. In this exemplary embodiment, a mirror 42 is arranged on the end effector 40. Additionally, the manipulator 30 in this exemplary embodiment has a holding frame 44 that carries the distance measuring device 46, in particular a laser-based distance measuring device. Here, the distance measuring device 46 is arranged such that it can generate a laser beam (not shown here), which irradiates the mirror 42 and can be deflected via the mirror 42 and enter free space. Similarly, the (reflected) laser beam arriving via the mirror 42 can be detected and evaluated by the distance measuring device 46.

[0059] The first coupling member 34 is here designed as a substantially U-shaped bracket with an elongated central part and is rotatably held at one end of the stator bracket 32 via a first rotary joint 48. Here, the rotary joint 48 is advantageously arranged in the region of the elongated central part. The reference numeral 50 denotes a first electric rotary drive, which is designed to rotate the first coupling member 34 relative to the stator 32 about a first axis of rotation 52, which is defined by the rotary joint 48. In this exemplary embodiment, the axis of rotation 52 extends through the mirror 42 and preferably extends collinearly with the laser beam (not shown here) of the laser-based distance measuring device 46.

[0060] Here, the second coupling member 36 is designed as a substantially L-shaped bracket or alternatively as a quarter-circular shaped bracket and is rotatably held on the second end of the stator bracket 32 via a second rotary joint 54. The reference numeral 56 denotes a second electric rotary drive which is designed to rotate the second coupling member 36 relative to the stator 32 about a second axis of rotation 58 which is defined by the rotary joint 54. In the exemplary embodiment shown here, the second axis of rotation 58 extends orthogonally relative to the first axis of rotation 52, and these two axes of rotation 52, 58 intersect at an axis intersection point 60 which in this case is centered on the mirror 42.

[0061] Here, the third coupling member 38 is designed as a substantially quarter-circular shaped bracket (alternatively designed as an L-shaped bracket) and is rotatably held on the second coupling member 36 via a third rotary joint 62. As can be seen in Figure 2 and Figure 3 the second rotary joint 54 and the third rotary joint 62 are arranged here at the ends of the L-shaped coupling member 36 remote from each other. The third rotary joint 62 defines a third axis of rotation 64 which in this exemplary embodiment extends orthogonally relative to the second axis of rotation 58. In other exemplary embodiments, the second axis of rotation and the third axis of rotation may extend at another angle to each other, for example at an angle of 45 degrees or 60 degrees. Advantageously, the third axis of rotation 64 intersects the first axis of rotation 52 and the second axis of rotation 58 at the axis intersection point 60.

[0062] Here, the end effector 40 is rotatably held on the first coupling member 34 via a fourth rotary joint 66 and is also rotatably held on the third coupling member 38 via a fifth rotary joint 68. In this exemplary embodiment, the fourth rotary joint 66 is advantageously a two-sided supported rotary joint. In this exemplary embodiment, the end effector 40 includes (another) substantially U-shaped bracket which is arranged between the two support bearings of the fourth rotary joint 66. The fifth rotary joint 68 is advantageously arranged in the central elongate part of the U-shaped bracket of the end effector 40. Alternatively, the first coupling member 34 and the U-shaped bracket of the end effector 40 may have an arcuate shape.

[0063] As can be seen from Figure 2 and Figure 3As can be seen, the spatial orientation of the mirror 42 can be changed by means of the connecting members 34, 36, 38 and the end effector 40. In particular, the mirror 42 can pivot here about two resulting axes of rotation, which in this case correspond to the axes of rotation 52, 58. The laser beam generated by the laser-based distance measuring device 46 can thus vary in the vertical direction (elevation) and the horizontal direction (azimuth).

[0064] Figure 4 Another exemplary embodiment of the novel manipulator is shown. The same reference numerals denote the same elements as before. Here, according to Figure 4 the manipulator carries a tactile measuring head 70, for example the tactile measuring head VAST XXT from Carl Zeiss Industrial Metrology GmbH, Oberkochen, Germany. Here, the measuring head 70 is releasably held on a probe exchange interface 72, which is formed on the end effector 40.

[0065] Figure 4 The stator 32, the first connecting member 34 and the end effector 40 of the manipulator according to are designed as annular elements. In this case, the stator 32 concentrically surrounds the first connecting member 34. In this case, the first connecting member 34 similarly concentrically surrounds the end effector 40. The first rotary joint is designed here on both sides and contains two bearing points 48a, 48b that are spaced apart from each other. Here, the second connecting member is similarly held on the stator 32 via a rotary joint having two bearing points 54a, 54b. Here, the second connecting member 36 and the third connecting member 38 are both designed as one-piece U-shaped brackets. In all preferred exemplary embodiments, for each rotary joint, the manipulator has at least one associated angle measuring sensor, one of which is indicated here, for example, by the reference numeral 74.

[0066] Figure 5 Another exemplary embodiment of the novel manipulator is shown. The same reference numerals denote the same elements as before. According to Figure 5 the manipulator corresponds to Figure 4 the manipulator, and shows the manipulator in a view of the exchange interface 72 looking from below. In this case, the optical measuring probe 76 is fastened, for example, to the exchange interface 72.

[0067] Figure 6 Another exemplary embodiment of the novel manipulator is shown. The same reference numerals denote the same elements as before. According to Figure 6 the manipulator has a similar structure to Figure 2 and Figure 3The bracket-shaped stator 32 and the bracket-shaped coupling members 34, 36, 38 of the manipulator. The probe exchange interface 72 is arranged on the end effector 40 and, in this case, releasably supports the stylet 78.

[0068] Figure 7 Another exemplary embodiment of the novel manipulator is shown. The same reference numerals denote the same elements as before. According to Figure 7 the manipulator is based on the exemplary embodiment according to Figure 2 and additionally has a hemispherical housing 80 in which a spherical segment 82 is mounted. Here, the hemispherical housing 80 is rigidly connected to the holding frame 44. The spherical segment 82 is connected to the end effector 40 and is mounted in the hemispherical housing 80 so as to be rotatable relative to the hemispherical housing 80. Here, the hemispherical housing 80 and the spherical segment 82 together form a spherical cap bearing by means of which the end effector is additionally supported. This support of the end effector 40 can be combined not only with the distance measuring device 46 but also with other exemplary embodiments shown here, where the end effector, for example, carries a stylet 78 or another sensor 70, 76.

[0069] In the exemplary embodiment according to Figure 7 the spherical segment 82 advantageously has a recess 84 which is arranged below the mirror 42 and opposite the distance measuring device 46. The recess 84 enables a large range of movement of the end effector 40, in particular about the second axis of rotation 58, without hiding the mirror 42 from the field of view of the distance measuring device 46. In other exemplary embodiments where this hiding is not a problem, the recess 84 can be omitted.

Claims

1. A manipulator for variable positioning of a movable element (42, 70, 76, 78) on a measuring machine (10), the measuring machine comprising: a stator (32) forming a manipulator base; a first coupling member (34), a second coupling member (36), and a third coupling member (38); A first, a second rotational joint, a third rotational joint, a fourth and a fifth rotational joint (48, 54, 62, 66, 68); and an end effector (40), wherein the first connecting member (34) is rotatably fixed to the stator (32) via the first rotational joint (48), wherein the second connecting member (36) is rotatably fixed to the stator (32) via the second rotational joint (54), wherein the third connecting member (38) is rotatably fixed to the second connecting member (36) via the third rotational joint (62), wherein the end effector (40) is rotatably fixed to the first connecting member (34) via the fourth rotational joint (66) and is also rotatably fixed to the third connecting member (38) via the fifth rotational joint (68).

2. The manipulator according to claim 1, wherein: The first rotary joint (48) defines a first rotary axis (52), wherein the second rotary joint (54) defines a second rotary axis (58), and wherein the first rotary axis (52) and the second rotary axis (58) intersect at a common axis intersection point (60).

3. A manipulator according to claim 1 or 2, wherein: The fourth rotary joint (66) has two supporting points, and the end effector (40) is rotatably arranged between the two supporting points.

4. The manipulator according to any one of claims 1 to 3, wherein: The first rotary joint (48) is a rotary joint installed on one side.

5. The manipulator according to any one of claims 1 to 3, wherein: The first rotary joint (48) has two supporting points (48a, 48b), and the first coupling member (34) is arranged between the two supporting points.

6. Manipulator according to any one of claims 1 to 5, wherein: The stator (32) surrounds the first coupling member (34) and the end effector (40) in an annular shape.

7. Manipulator according to any one of claims 1 to 6, wherein: The first coupling member (34) is designed in an annular shape.

8. Manipulator according to any one of claims 1 to 7, wherein: The second coupling member (36) is designed in a partial annular shape.

9. Manipulator according to any one of claims 1 to 8, wherein: The first, second and / or third coupling members (34, 36, 38) are each designed as a rigid, one-piece bracket or ring.

10. The manipulator according to any one of claims 1 to 9, further comprising a first and a second rotary drive (50, 56), wherein: The first rotary drive (50) is designed to rotate the first coupling member (34) relative to the stator (32), and wherein the second rotary drive (56) is designed to rotate the second coupling member (36) relative to the stator (32).

11. The manipulator according to any one of claims 1 to 10, wherein: Each of the rotary joints (48, 54, 62, 66, 68) has an associated angle measurement sensor (74) designed to determine the current rotary angle position of the respective rotary joint (48, 54, 62, 66, 68).

12. Manipulator according to any one of claims 1 to 11, wherein: At least one of the rotational joints (48, 54, 62, 66, 68) is lockable to prevent rotational movement.

13. Manipulator according to any one of claims 1 to 12, wherein: The end effector (40) has a deflection mirror (42).

14. Manipulator according to any one of claims 1 to 13, wherein: The end effector (40) has a probe exchange interface (72) which is designed to hold a measurement probe (70, 76, 78).

15. Manipulator according to any one of claims 1 to 14, wherein: The end effector (40) is also mounted in a spherical cap (80, 82).

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