Positioning device and method for operating a positioning device of this type

Abstract

The invention relates to a positioning device (1) comprising: - a base (2); - at least four electromechanical drive units (3) which are disposed on the base along a periphery (BU) of the base (2) such that they are opposite one another in pairs and which are mechanically connected to the base, each drive unit (3) having two actuators (4) which can be deflected by appropriate control and which are arranged in a V-shape relative to one another and having a friction element (5) which connects the two actuators to one another; - a platform (7) which, by means of a bearing system (6), is mounted for movement relative to the base (2) at least along two orthogonal movement axes (BA1, BA2) in a movement plane (BE) spanned by said axes; and - a rotor (8) which is coupled to the platform (7) and is driven by the drive units (3) and which has a frictional element (9) and a spring element (10), wherein: the spring element (10) presses the friction element (5) of a drive unit (3) against the frictional element (9) such that, in the undeflected state of the actuators (4), the friction element is in contact with the frictional element (9) and, in the deflected state, the friction element can cause at least one of the other friction elements (5) to mechanically lift off of the frictional element (9); by appropriate control of the particular drive unit (3) and by the resulting deflection of its actuator (4), a movement of the particular friction element (5) with movement components parallel to the movement plane (BE) results and thus positioning movements of the platform (7) can be produced at least linearly along the two orthogonal movement axes (BA1, BA2). The invention also relates to a method for operating a positioning device of this type.

Description

Positioning device and method for operating such a positioning device

[0001] The invention relates to a positioning device according to claim 1 and a method for operating such a positioning device according to claim 14.

[0002] From DE 10 2019 126 702 B3 by the applicant, a rotation adjusting device is known in which the rotary drive of a rotor is realized via at least four drive units, each of the drive units having two actuators arranged in a V-shape relative to one another and connected to one another via a common friction element. The rotor in this case comprises a spring device formed integrally therewith, via which spring device the friction elements are pressed against the rotor, so that movements of the friction element of a drive unit caused by the control of the actuators of said drive unit can be transferred to the rotor. The rotor is mounted in such a way that only rotational movements thereof are possible, so that a shaft of the rotor protruding from the housing of the rotation adjusting device performs an analogous, i.e. purely rotary, movement which is transmitted to a driven element which can be coupled to the shaft.element to be positioned is transferable.

[0003] It is an object of the invention to provide a positioning device which allows at least adjusting or positioning movements of a platform along two orthogonal axes of movement in a plane of movement spanned by these axes.

[0004] This object is achieved by a positioning device according to claim 1, wherein the dependent claims referring back thereto contain at least expedient developments of the positioning device.

[0005] Furthermore, it is an object of the invention to provide a method for operating an aforementioned positioning device which ensures at least adjusting or positioning movements of the platform along two orthogonal axes of movement in a plane of movement spanned by these axes.

[0006] The above object is achieved by a method according to claim 14, wherein the dependent claims referring back thereto contain at least expedient developments of the method.

[0007] The positioning device according to the invention comprises a base, a platform movable relative to or with respect to the base at least along two orthogonal axes of movement in a plane of movement spanned by these axes of movement, and a runner coupled to the platform.

[0008] To drive the rotor, at least four electromechanical drive units are arranged in pairs opposite one another along a circumference of the base and mechanically connected to it, which, in the case of four drive units arranged on the base, form a first and a second drive unit pair, wherein each drive unit has two actuators which can be deflected by appropriate control and are arranged in a V-shape relative to one another, and a friction element which connects the two actuators to one another.

[0009] The runner, coupled to the platform and driven by the drive units, comprises a friction element and a spring element, which, based on a respective change in length of the latter, provides spring travel along a spring axis of the spring element. The friction element and / or the spring element do not necessarily have to be separate or independent elements, but can also each be formed integrally with the runner and then form a corresponding section of the runner. The spring element presses the friction element of a drive unit against the friction element with a defined spring force in such a way that, when the actuators are not deflected or not activated, the friction element is in contact with the friction element and movements of the friction element can be transmitted to the friction element or the runner, and when deflected or activated, the spring element can cause at least one of the other friction elements to be mechanically lifted off the friction element.In particular, the platform is designed as a driven element or as a connection point for attaching a driven element.

[0010] By means of a corresponding electrical control of the respective drive unit and by means of the resulting deformation or deflection of its two actuators, a movement of the associated friction element results with movement components arranged or running at least parallel to the movement plane, so that positioning movements of the platform can be realized at least linearly along the two orthogonal movement axes.In particular, the positioning device is configured such that by appropriately controlling at least one respective drive unit, a deflection of its actuators and a movement of the respective friction element with movement components arranged parallel to the plane of movement and thereby one or both of the following actuating movements (M1), (M2) of the platform takes place: (M1) a linear actuating movement along two mutually orthogonal axes of movement, which each run transversely to the spring axis, (M2) a rotation about an axis of rotation which runs along the spring axis. In this case, the drive units are generally controlled such that the movement of the associated friction element also includes movement components which are arranged perpendicular to the plane of movement or run perpendicular to this. Control in which a superposition of movement components of the corresponding friction element running parallel and perpendicular to the plane of movement takes place and the friction element or a point or an area thereof describes a circular or elliptical movement path or trajectory.

[0011] By providing and arranging a suitable bearing, the mobility or adjustability of the platform relative to the base at least along two orthogonal axes of movement in a plane of movement spanned by these axes of movement is achieved in order to realize a positioning device with at least two translational degrees of freedom.

[0012] It may be advantageous for the bearing to be designed in such a way that it additionally allows rotation of the platform in the plane of movement around a rotation axis perpendicular to the plane of movement. This allows for the integration of an additional degree of freedom, namely a rotational degree of freedom, into the positioning device in a comparatively simple manner.

[0013] It can also be advantageous for the bearing to be implemented by a plain bearing, preferably with a flat sliding guide element. If the bearing is designed as a plain bearing and has a flat sliding guide element, it can be particularly advantageous for the flat sliding guide element to be arranged between the base and the platform and to be in frictional contact with the platform. Thus, the platform is directly supported on the flat sliding guide element and is guided by a planar frictional contact with it within the frictional contact plane with regard to corresponding adjusting or positioning movements, thereby enabling both linear or translational as well as rotational movements of the platform.

[0014] It may also be advantageous for the bearing arrangement to comprise two separate linear bearings for separately guiding the movement of the platform in the plane of movement along each of the aforementioned orthogonal axes of movement. This creates dedicated and independent linear guides. If, in addition to the two linear movements enabled by the separate linear bearings, a rotational movement of the platform about the rotation axis arranged perpendicular to the plane of movement is also to be realized, it may be advantageous for the bearing arrangement to enable the rotational movement of the platform to be realized by a rotational bearing, preferably in the form of a rolling bearing, wherein the rotational bearing is mechanically connected to one of the two separate linear bearings.

[0015] It may also be advantageous for the drive units to be arranged between the base and the friction element of the rotor, and for the spring element of the rotor to be connected to the platform, preferably directly or immediately, in such a way that the platform is decoupled from movements of the friction elements in a direction that runs perpendicular or substantially perpendicular to the plane of movement, and therefore the above-described movements of the friction elements are not transmitted to the platform. In this way, movements of the friction elements that are arranged perpendicular or substantially perpendicular to the plane of movement and result from a dimensional change and in particular an increase in the length of the actuators and thus run in a direction away from the platform, lead to a deformation or change in length of the spring element in an analogous direction, i.e.perpendicular or essentially perpendicular to the plane of movement, which pushes the platform towards the base or the bearing and thus the corresponding movement components of the friction elements are not transferred to the platform or the platform is decoupled from these movement components.

[0016] In addition, it can be advantageous for the spring element of the rotor to be indirectly connected or coupled to the platform via a sliding guide component that is at least partially flat and via the friction element, wherein the sliding guide component is pressed against the friction element by means of the spring element and the friction element is pressed against the friction elements, and the friction element is mechanically connected to the platform, whereby a linear movement of the platform in the direction perpendicular to the plane of movement as well as tilting movements about the two orthogonal axes of movement can be realized, so that a total of six degrees of freedom with regard to the movement of the platform are provided.

[0017] In the embodiment described above, it is explicitly intended or desired that movements of the friction elements in a direction that is arranged perpendicular or substantially perpendicular to the plane of movement and points towards the platform are transferred to the platform and thus, in addition to the translational movements of the platform along the two axes of movement spanning the plane of movement, adjusting or positioning movements of the platform in a direction perpendicular to the plane of movement as well as tilting movements about the orthogonal axes of movement spanning the plane of movement are enabled, whereby the positioning device has three translational and three rotational degrees of freedom.

[0018] In this case, it may be particularly advantageous for the sliding guide component to be arranged at least in sections between the friction element and the platform and at a distance from this is arranged. In this way, the friction element, which is in surface frictional contact with the sliding guide component, is guided along or in the frictional contact plane, along with the platform mechanically connected to the friction element. At the same time, the connection or coupling of the sliding guide component to the spring element allows tilting movements of the latter around the two orthogonal axes of movement spanning the movement plane, which enables corresponding tilting movements of the friction element, which is in surface frictional contact with the sliding guide component, and thus of the platform.

[0019] It may be advantageous for the actuators to comprise, and preferably consist of, an electromechanical material. It may prove particularly advantageous for the actuators to be made of piezoelectric and preferably piezoceramic material.

[0020] Furthermore, it can be advantageous for the positioning device to have a device for acquiring and processing measurement or operating data relevant to the state of the positioning device, which device, in particular, comprises corresponding sensors and is designed to continuously acquire and process the measurement or operating data during the running time of the positioning device and optionally link them together so that an image of the state of the positioning device can be derived therefrom. From this image of the state of the positioning device or the corresponding information, possible measures can be derived, such as the replacement of a component or element that is highly likely to fail in the near future. Remote monitoring of the state of the positioning device is also conceivable in this regard.

[0021] A method according to the invention for operating a positioning device outlined above for realizing translational movements of the platform along the two orthogonal movement axes is characterized in that at least one of the at least two drive unit pairs is controlled in such a way that at least one component of the resulting movement of its friction elements is rectified and runs along or parallel to the corresponding movement axis, and an analog translational movement of the platform along the respective movement axis results.

[0022] Thus, two drive units arranged opposite one another with respect to the circumference of the base serve the translational adjustment or positioning movement of the platform along the respective movement axis within the movement plane. Consequently, in the simplest case, two drive unit pairs, or a first and a second drive unit pair with a total of four drive units, are available for the movement of the platform along the two orthogonal movement axes, with one of the Pairs of drive units - for example, the first pair of drive units - is essentially responsible for the movement along one of the movement axes (for example along the x-axis), and the other of the two pairs of drive units - in the present example, the second pair of drive units - is essentially responsible for the movement along the other of the movement axes (the y-axis).

[0023] In the case outlined above, the connecting line between the two drive units of the respective drive unit pair is preferably aligned substantially perpendicular to the corresponding movement axis. Thus, the connecting line between the two drive units of the drive unit pair responsible for movement along the x-axis runs along or parallel to the y-axis, and vice versa.

[0024] It may be advantageous here that at least two pairs of drive units are arranged at least along two different circumferences of the base, thus providing a total of at least eight drive units, and in order to implement movements of the platform along the orthogonal axes of movement in the plane of movement, the respective pair of drive units arranged along one of the circumferences is controlled in such a way that at least one component of the resulting movement of its friction elements is in the same direction and runs along or parallel to the corresponding axis of movement, and the other pair of drive units responsible for moving the platform along the same axis of movement and arranged along the respective other circumference is controlled in such a way that at least one component of the resulting movement of its friction elements is in the same direction and runs along or parallel to the corresponding axis of movement,whereby the control of the different drive unit pairs is phase-shifted to each other.,

[0025] Thus, for example, in the presence of two pairs of drive units arranged with respect to two different circumferences of the base (hereinafter referred to as the first and second pair of drive units), it is possible, after carrying out a first drive step along the respective movement axis caused by the friction elements of the first pair of drive units, to subsequently carry out a second drive step along the same movement axis caused by the friction elements of the second pair of drive units, without having to wait for a return movement of the friction elements of the first pair of drive units opposite to the drive movement in order to prepare for a subsequent drive step of this pair of drive units, and a quasi-continuous or essentially uninterrupted movement of the platform along the respective movement axis takes place.

[0026] In the event that the positioning device, in addition to realizing translational movements of the platform along the orthogonal axes of movement in the plane of movement, allows rotational movements of the platform about a rotation axis running perpendicular to the plane of movement, it can be advantageous that, in order to realize the rotational movement, at least one of the drive unit pairs is controlled in such a way that at least one component of the resulting movement of its friction elements is in the same direction with respect to a circumference of the base, and at least one other of the drive unit pairs is controlled in such a way that at least one component of the resulting movement of its friction elements is in the same direction with respect to a circumference of the base, wherein the control of the different drive unit pairs or the control of the drive units of a drive unit pair takes place out of phase with respect to one another.The terminology "co-directional with respect to or along the circumference" used above means that the phase-shifted movement of the friction elements of the different drive unit groups along the circumference is either clockwise or counterclockwise, so that all friction elements contribute to a corresponding co-directional and rotational movement of the platform in or counterclockwise direction.

[0027] The term “along” here means in the context of a directional indication mentioned herein, which in particular can also relate to the course of a contour line or a surface or a direction of a part or a structural component such as an axis or a shaft or a central axis thereof, in relation to a reference direction or a reference axis, that a section of the course or the tangent to a respective contour line or respective surface or the direction in an explicitly or implicitly specified viewing direction deviates locally or in sections by an angle of a maximum of 45 degrees and in particular of a maximum of 30 degrees from the respective reference direction or reference axis to which the respective directional indication is related, wherein the angle is in particular the smaller of two supplementary angles adding up to 180 degrees.The term “transverse” here means in the context of a directional indication mentioned herein, which in particular can also relate to the course of a contour line or a surface or a direction of a part or a structural component such as an axis or a shaft or a central axis thereof, in relation to a reference direction or a reference axis that a section of the course or the tangent to a respective contour line or respective surface or the direction in an explicitly or implicitly predetermined viewing direction deviates locally or sectionally by an angle which is between 45 degrees and 135 degrees, and preferably by an angle which is between 67 degrees and 113 degrees, from the respective reference direction or reference axis to which the respective directional indication is related. Advantages and. The advantages of the invention will become clearer from the following description of preferred embodiments with reference to the figures.

[0028] Fig. 1 : Sectional view of a positioning device according to the invention, the platform of which has translational degrees of freedom of movement within the plane of movement BE and a rotational degree of freedom of movement around the axis of rotation RA

[0029] Fig. 2: a) sectional view of a positioning device according to the invention, the platform of which has two translational degrees of freedom of movement within the movement plane BE and one rotational degree of freedom of movement about the rotation axis RA, wherein the two translational degrees of freedom of movement are realized by two separate and mutually coupled linear bearings, along a first sectional plane; b) schematic sectional view of the positioning device according to the invention according to Fig. 2a) along a second sectional plane

[0030] Fig. 3: Sectional view of a positioning device according to the invention, the platform of which has translational degrees of freedom within the movement plane BE as well as one translational degree of freedom in a direction perpendicular to the movement plane BE and additionally three rotational degrees of freedom

[0031] Fig. 4a)-c): Schematic representation to illustrate a method according to the invention for controlling a positioning device according to the invention with two pairs of drive units arranged opposite one another with respect to a circumference for realizing movements along two orthogonal movement axes (x and y axes)

[0032] Fig. 5 a)-b): Schematic representation to illustrate a method according to the invention for controlling a positioning device according to the invention with two pairs of drive units arranged opposite one another with respect to a circumference for realizing rotary movements

[0033] Fig. 6a)-c): Schematic representation to illustrate a method according to the invention for controlling a positioning device according to the invention with three pairs of drive units arranged opposite one another with respect to a circumference for realizing movements along two orthogonal axes of movement

[0034] Fig. 7a)-b): Schematic representation to illustrate a method according to the invention for controlling a positioning device according to the invention with three pairs of drive units arranged opposite one another with respect to a circumference for realizing rotary movements

[0035] Fig. 8a)-c): Schematic representation to illustrate a method according to the invention for controlling a positioning device according to the invention with three pairs of drive units arranged opposite one another with respect to a first circumference and with two pairs of drive units arranged opposite one another with respect to a second circumference for realizing movements along two orthogonal movement axes

[0036] Fig. 9a)-b): Schematic representation to illustrate a method according to the invention for controlling a positioning device according to the invention with three pairs of drive units arranged opposite one another with respect to a first circumference and with two pairs of drive units arranged opposite one another with respect to a second circumference for realizing rotary movements.

[0037] Fig. 1 shows a sectional view of a first embodiment of a positioning device 1 according to the invention, which allows translational movements of its platform 7 within a movement plane BE as well as rotational movements of the platform 7 about a rotation axis RA. The platform 7 is fixedly and in particular rotationally connected to a shaft 82 of a rotor 8 via a screw connection, to which a spring element 10 is connected in a direction pointing away from the platform. The spring element 10 is formed integrally with the rotor 8 and forms a corresponding section of the rotor. The spring element 10 defines a spring axis, along the direction of which the spring element 10 provides a spring travel due to a respective change in its length. The shaft 82 has a shaft axis that runs along the spring axis.The base 2 has a central space which extends in the direction of the shaft axis and in which at least a section of each of the spring element 10 and the shaft 82 is located. The spring element 10 or the corresponding section of the rotor 8 is realized by a hollow cylindrical structure with transverse slots formed therein, wherein the spring element 10 preferably has and is preferably made of a metallic material. Adjoining the spring element 10 is a projection section 84, which is also formed integrally with the rotor 8, i.e. a section which extends or projects laterally relative to the spring element 10 and on which a friction element 9 is arranged and firmly connected thereto.A first end of the spring element 10 is directly or indirectly connected to or attached to the projection section 84, with a second end of the spring element 10 located behind the first end of the respective actuator 4, as viewed from the platform 7. The second end of the spring element 10 is connected to the shaft 82. The positioning device 1 can also be implemented without a shaft 82. In this case, a second end of the spring element 10 can be connected to the platform 7 or attached to it.

[0038] Friction elements 5 of a total of four drive units 3 arranged along a circumference of a base 2 and firmly connected to the base 2 are in frictional contact with the friction element 9. Due to the sectional view, only three of the four drive units 3 are visible. Each of the four drive units 3 is identically constructed and comprises two piezoelectric actuators 4 with a columnar shape, so that their length is significantly greater than their other dimensions. The two piezoelectric actuators 4 of a drive unit are arranged in a V-shape relative to one another and are connected to one another in the region of the tip of the V via the friction element 5.

[0039] By suitable electrical control of the two piezoelectric and column-shaped actuators 4 of a drive unit 3, in which these perform dimensional changes and essentially changes in their length, defined movements or movement paths or trajectories can be assigned to the friction element 5, so that due to the frictional contact between the friction element 5 and the friction element 9, the targeted movements of the friction element can be used to drive the rotor 8 and thus the platform 7. The movements orMovement paths of a friction element 5 comprise at least components that run parallel or substantially parallel to the movement plane BE, resulting in a corresponding planar movement of the friction element 9 in frictional contact with the friction element 5, which is transmitted to the slider 8 rigidly connected to the friction element 9 and ultimately leads to an analogous movement of the platform 7 rigidly connected to the slider. The contact points or surfaces of the friction elements 5 and the friction element 9 together define a plane that corresponds to an effective plane WE, i.e., a plane within which the movements or movement components of the friction elements 5 act on the element to be directly driven thereby—here in the form of a dedicated friction element 9—and thereby drive the same and, indirectly, lead to an analogous drive of the platform 7.It should be noted in this context that the effective plane WE does not coincide with the movement plane BE and is arranged at a significant distance from it.

[0040] The positioning device 1 according to the invention has a bearing 6 which is configured such that the platform 7 is movable relative to the base 2 at least along two mutually orthogonal and each transverse to the spring axis movement axes BA1, BA2, which each run transverse to the spring axis and in a movement plane BE spanned by these axes. The combination of the spring element 10, the cantilever section 84 connected thereto and the shaft 82 are thus freely movable within the central space of the base 2, in particular along the movement axes BA1, BA2, so that the spring element 10 and the Cantilever section 84 are suspended from the platform and mounted floatingly thereon. The central space of the base 2 extends in directions transverse to the axis of rotation RA over a width which permits movements of the spring element 10 resulting from a movement of the platform 7 along the axes of movement BA1, BA2. The embodiment of Figure 1 has a bearing 6 with a particularly planar sliding guide element 62. The platform 7 is supported with its lower planar surface in Figure 1 on the planar sliding guide element 62 of the bearing 6 designed as a plain bearing, wherein the planar sliding guide element 62 itself is arranged on a section of the base 2 and is firmly connected thereto, and the planar sliding guide element 62 is arranged between the base 2 and the platform 7. There is therefore planar contact between the platform 7 and the sliding guide element 62, wherein the corresponding contact plane corresponds to the plane of movement BE.It should be noted in this context that the contact surface between a friction element 5 and the friction element 9 overlaps with the contact surface between the platform 7 and the flat sliding guide element 62.

[0041] The above-described design of the bearing 6 results in a guidance of the platform 7 within the movement plane BE, which is otherwise not subject to any further constraints, so that any movements within the movement plane BE, including rotational movements about the rotation axis RA, which is oriented perpendicular to the movement plane BE, are possible, and these movements are only limited by the geometry of the base 2, within which the rotor 8 can move in the respective translational direction until it strikes the base 2. In this regard, however, precautions can be taken to prevent mechanical impact of the rotor 8 on the base 2, for example by providing optical, magnetic or electrical sensors which, in controlled operation with corresponding control of the drive units, transmit the current position of the rotor 8 to a control unit.With regard to the movements or directions of movement listed above, the rotor 8 behaves essentially like a rigid body which transmits the drive movements imposed on the friction element 9 by the friction elements 5 to the platform 7 without loss or essentially without loss.

[0042] However, the movements or movement paths of a friction element 5 generally also include components that run perpendicular or substantially perpendicular to the movement plane BE, for example, in the case where the friction element executes a circular or elliptical movement path by controlling the actuators of a drive unit. In the positioning device 1 according to Fig. 1, precisely these movement components should not be transferred to the platform 7, which is primarily due to the spring element and its arrangement is accomplished. The actuators 4 of the drive units 3 each have a first end, with which they are attached directly or indirectly, i.e. via a further component, to the base 2, and a second end which is located opposite the first end in a direction running along the spring axis and to which the respective friction element is attached directly or indirectly. The second end of the respective actuator 4 is located behind the first end of the respective actuator 4, as seen from the platform 7. As a result, movements of the friction elements in a direction away from the platform 7 or the bearing 6, which runs perpendicular or essentially perpendicular to the plane of movement BE, lead to a similar movement of the friction element 9 and thus to a deformation or extension of the spring element 10, which results in a corresponding spring force. This spring force urges the platform 7 against the bearing 6 orthe sliding guide element 62, however, no corresponding movement of the platform 7 results along a direction perpendicular or substantially perpendicular to the movement plane BE. This provides a reliable decoupling of the movement components of the platform 7 from the movement components of the friction elements 5, which run perpendicular or substantially perpendicular to the movement plane BE, thereby ensuring that the platform 7 only performs movements within the movement plane BE.

[0043] Fig. 2 illustrates, in two sectional views along different sectional planes, a further positioning device according to the invention which, with regard to the arrangement of the actuators and the friction element 9, is implemented like the embodiment in Figure 1: The second end of the respective actuator 4 is located, as seen from the platform 7, behind the first end of the respective actuator 4, which is attached directly or indirectly to the base 2. The bearing 6 is configured such that it has two translational degrees of freedom of movement of the platform 7 relative to the base 2 within the movement plane BE and one rotational degree of freedom of movement of the platform 7 relative to the base 2 about the rotation axis RA, wherein the two translational degrees of freedom of movement are implemented by two separate and interconnected linear bearings 64, 66.A first linear bearing 64 of the bearing 6 is designed such that it allows relative movements of a first component of the base 2 with respect to a second component of the base 2 along the first movement axis BA1, and a second linear bearing 66 of the bearing 6 is designed such that it allows relative movements of the second component of the base 2 with respect to a third component of the base 2 along the second movement axis BA2, wherein the first, second and third components of the base 2 are located one behind the other in the direction of the spring axis and as seen from the platform 7. While the lower linear bearing 64 and its bearing components can be seen from the corresponding sectional plane in Fig. 2a), the upper linear bearing 66 and its bearing components can be seen from Fig. 2b. By coupling the two linear bearings, when the linearly movable part of one of the linear bearings moves or shifts, the other linear bearing is carried or dragged along. The combination of the spring element 10, the cantilever section 84 connected to it, and the shaft 82 is thus freely movable within the central space of the base 2, so that the spring element 10 and the cantilever section 84 connected to it are suspended from the platform and mounted in a floating manner thereon. The central space of the base 2 extends in directions transverse to the rotation axis RA over a width that allows movements of the spring element 10 resulting from a movement of the platform 7 along the movement axes BA1, BA2.

[0044] A rotational bearing 68 of the bearing 6 is firmly connected to the upper linear bearing 66 or to the component of the upper linear bearing 66 adjacent to the platform 7, which rotational bearing 68 supports the shaft 82 of the rotor 8 on the first component of the base 2 in such a way that the latter can perform rotational movements about the rotation axis RA and, with it, the platform 7 which is firmly connected to the shaft 82, so that the rotational degree of freedom of the platform 7 is realized in this way.

[0045] In contrast to the positioning device according to Fig. 1, here the two translational degrees of freedom for movements of the platform within the plane of movement BE as well as the rotational degree of freedom for movements of the platform around the axis of rotation RA are clearly defined or fixed by the corresponding linear and rotational bearings.

[0046] Fig. 3 shows an illustration of a further embodiment of a positioning device according to the invention, which has the platform 7 and a sliding guide component 63 which is located along the spring axis between the platform 7 and the spring element 10. The first end of the respective actuator 4, which is fastened directly or indirectly to the base 2, is located, as seen from the platform 7, behind the second end of the respective actuator 4, to which the respective friction element is directly or indirectly fastened. The platform 7 and the sliding guide component 63 are coupled to one another via the friction element 9. The friction element 9 of this embodiment is connected to the platform 7 directly or indirectly, i.e. via an intermediate component, and in particular is fastened to the latter. At least a portion of the sliding guide component 63 contacts a sliding surface of the friction element 9. At least a portion of the sliding surface can be realized as a flat surface.The friction element 9 can be implemented as a component that rotates around the rotation axis RA. In this case, the sliding guide component 63 can also be implemented as a component that rotates around the rotation axis RA. The second end of the actuators 4 of the drive units 3 of this embodiment 4 is located in front of the first end of the respective actuator 4, as viewed from the platform 7. Bearing 6 is configured in such a way that it provides a total of six degrees of freedom with respect to the platform 7 relative to the base 2, namely three translational and three rotational degrees of freedom. The translational movements or movement components of the platform 7 can have one or more of the following directions: along the movement axis BA1, along the movement axis BA2 and along the rotation axis RA. The central space of the base 2 extends in directions transverse to the rotation axis RA over a width that allows movements of the spring element 10 resulting from a movement of the platform 7 along the movement axes BA1, BA2. Since the spring element 10 of the rotor 8 is connected orcoupled, the spring element 10 presses the sliding guide component 63 against the friction element 9 and this against the friction elements 5, and the friction element 9 is mechanically connected to the platform 7. As a result, in addition to the translational movements of the platform 7 along two orthogonal axes of movement BA1, BA2, a translational movement in a direction perpendicular to the plane of movement BE, ie along the axis of rotation RA, as well as rotational movements about the axis of rotation RA and rotational movements or tilting movements of the platform 7 about the two orthogonal axes of movement BA1, BA2 can be realized.

[0047] A significant difference between the positioning device according to Fig. 3 and the positioning devices shown in Figures 1 and 2 is the fact that here the effective plane WE, which corresponds to a plane spanned jointly by the contact points or surfaces of the friction elements 5 with the friction element 9, coincides or essentially coincides with the movement plane BE, wherein here again the contact surface between a friction element 5 and the friction element 9 is in overlap with the contact surface between the sliding guide component 63 and the friction element 9, wherein the respective surfaces are directly opposite one another with respect to the friction element 9.

[0048] Figures 4a) and 4b) contain a schematic representation to illustrate a method according to the invention for controlling a positioning device according to the invention with two pairs of individual drive units arranged opposite one another with respect to a circumference BU for realizing translational movements along two orthogonal movement axes BA1 and BA2, wherein the movement axis BA1 corresponds to the x-axis or coincides with it, and the movement axis BA2 corresponds to the y-axis or coincides with it. In Figures 4a) and 4b) one can see the base 2, which is only shown very schematically, with a circular shape, in which along a likewise circular circumference BU of the base 2, which has a smaller radius than the outer circumference of the base 2, a total of four individual drive units 3 are arranged in equidistant manner, ie, at an angular distance of 90° from each other. The two drive units 3 arranged opposite one another with respect to the circumference BU form a corresponding drive unit pair, so that two drive unit pairs are present.

[0049] In Fig. 4a), the two drive units forming a corresponding drive unit pair, which are arranged opposite one another along the y-axis or along the movement axis BA2 and with respect to the circumference BU of the base 2, are marked "A", while the two drive units forming a corresponding drive unit pair, which are arranged opposite one another along the x-axis or along the movement axis BA1 with respect to the circumference BU of the base 2, are marked "B". These markings "A" and "B" serve to assign the movements or positions of the friction elements of the corresponding drive unit pair relative to the rotor 8, shown schematically in the individual illustrations i) to vii) in Fig. 4c), at different or subsequent times of translational drive steps.Identical marking of both drive units of a drive unit pair also indicates that these drive units are controlled identically.

[0050] In Fig. 4a), the two cooperating drive units marked with “A” or the corresponding pair of drive units, which will also be referred to as “A” or “B” in the following, are used to drive or position the platform along or parallel to the x-direction. For this purpose, the drive units “A” are controlled in all phases of a drive step in such a way that their friction elements move synchronously in the same direction and in the same direction in order to jointly drive the platform in the positive x-direction through the corresponding synchronous movement, while the drive units “B” are controlled in all phases of a drive step in such a way that their friction elements move synchronously in the same direction and in the same direction in order to jointly drive the platform in the positive x-direction through the corresponding synchronous movement, which differs from the direction of movement orThe motion trajectory of the friction elements of drive units "A" differs from the other drive units, supporting the drive process generated by drive units "A" without itself providing a drive in or along the drive direction of the platform. Illustrations i) to iv) of Fig. 4c) indicate the sequence of two subsequent drive steps.

[0051] As can be seen in Fig. 4c) from the top illustration i), in a certain temporal phase of a drive step, the friction elements of the drive units “A” are out of contact with the rotor 8 and lifted off it, and the actuators of the drive units “A” are controlled in such a way that their friction element moves opposite to the drive direction and simultaneously towards the rotor. The drive units “B” or their In contrast, actuators are controlled in such a way that their friction elements are in frictional contact with the rotor 8 or are pressed against it, thereby holding the position of the rotor 8 achieved in a previous drive step or the starting position of the rotor by clamping it. In this context, with the given arrangement of the drive units and with regard to the exclusive movement of the rotor 8 in or along the x-direction, the drive units "B" do not actually serve directly to drive or generate a drive movement, but rather to appropriately support the drive of the rotor 8 caused by the drive units "A", in that the drive units "B" hold or clamp the rotor 8 in its current position of the respective drive step at least as long as the friction elements of the drive units "A" are lifted off the rotor or are out of contact with it.

[0052] In a subsequent phase of the same drive step (see illustration ii) of Fig. 4c)), the drive units "A" or their actuators are controlled such that their friction element comes into direct or indirect contact or frictional contact with the rotor 8, preferably at the maximum achievable position opposite to the drive direction, while the drive units "B" or their actuators are controlled such that their friction elements lift off the rotor and are no longer in frictional contact with it, and the corresponding lifting movement preferably occurs in or along a direction perpendicular to the drive direction. Ideally, this lifting occurs exactly at the time at which the friction elements of the drive units "A" come into frictional contact with the rotor.However, a certain temporal overlap of the friction contact of the friction elements of the drive units “A” and “B” in this phase of a drive step is also conceivable and may offer technical advantages under certain circumstances.

[0053] In the state of frictional contact between the friction elements of drive units "A," the drive units "A" are subsequently controlled in such a way that, while maintaining frictional contact, the friction elements move with at least one movement component in the drive direction (here, the positive x-direction). Due to the frictional contact, the runner 8 is driven and performs a corresponding drive step, which ultimately leads to an analogous drive step of the platform connected to the runner. During this phase of the drive step, the friction elements of drive units "B" are still out of contact with the runner.

[0054] At the latest at the time when the position of the friction elements of the drive units “A” or the corresponding deflection of their actuators with regard to the drive direction preferably reaches its maximum achievable value and shortly before a Control of the drive units “A” (ie according to illustration iii) of Fig. 4c)), which leads to a return or return movement of their friction elements into a position according to sketch i), the drive units “B” are controlled in such a way that their friction elements come into frictional contact with the rotor and are pressed against it, and the corresponding contact movement preferably takes place in or along a direction perpendicular to the drive direction.Ideally, this contacting takes place exactly at the time at which the friction elements of the drive units “A” lift off the runner to realize the return or return movement, in particular to avoid increased frictional wear due to the friction contact between the friction elements of the drive units “B” and the runner 8, but also to generate no or only a negligible parasitic movement of the runner during the return movement of the friction elements of the drive units “A” and their corresponding engagement by them.

[0055] According to illustration iv) of Fig. 4c), in this phase of the drive step, the friction elements of the drive units "B" are in contact with the runner, while the friction elements of the drive units "A" have already started their return movement and are thus out of contact with the runner 8. This again ensures that the position of the runner 8 or the platform connected to it reached within the drive step is maintained or fixed.

[0056] The representations v) to vii) following representation iv) of Fig. 4c) downwards are identical to the sketches i) to iii) shown above and sketch identical phases or identical movements or positions of the respective friction elements of a subsequent drive step, which is why they are not explained in more detail here.

[0057] In Fig. 4b), the two interacting drive units marked "A" or the corresponding drive unit pair serve to drive or position the platform along or parallel to the y-direction. For this purpose, the drive units "A" are controlled in all phases of a drive step such that their friction elements move in the same direction and in the same direction to jointly drive the platform in the positive y-direction. The illustrations i) to iv) of Fig. 4c) indicate the sequence of two drive steps as described above; therefore, to avoid repetition, they will not be discussed in detail here.

[0058] The above-described methods are merely those for realizing translational movements of the platform either solely or exclusively along the movement axis BA1 or solely or exclusively along the movement axis BA2 and using solely or controlling the control system for the movement along the respective movement axis BA1, BA2 responsible drive unit pair. However, it is conceivable to control different drive unit pairs of the positioning device in chronological order. This can be useful, for example, if, despite exclusive control of the drive units of one drive unit pair, due to tolerances in the components or elements of the positioning device, there is no pure movement of the platform in or along the corresponding movement axis BA1, BA2, but also a parasitic movement in or along the respective other movement axis. If, for example, by controlling the drive unit pair “A” according to Fig. 4a), a translational movement step of the platform is intended exclusively in the positive x-direction, a parasitic movement of the platform in the y-direction can occur due to tolerances in the components of the positioning device.By suitable control of at least one of the and preferably both drive units of the drive unit pair “B” following the drive step for realizing the movement in the x-direction by controlling the drive units of the drive unit pair “A”, the aforementioned parasitic movement of the previous drive step can be effectively compensated.

[0059] It is also conceivable to control different drive unit pairs in an alternating or alternating manner. For example, with regard to Fig. 4a), the two drive unit pairs “A” and “B” can be controlled in an alternating sequence in order to generate a respective drive step of the platform in or along the respective movement axis BA1, BA2, so that a movement step occurs alternately in the corresponding x-direction and in the corresponding y-direction, and thus a movement of the platform along a diagonal is possible (diagonal travel). Furthermore, any sequences of control of the two drive unit pairs “A” and “B” are conceivable in order to generate any movements or movement paths of the platform. In addition to the alternating and chronologically sequential control of the drive unit pairs, it is conceivable to control the drive unit pairs with temporal overlap, at least in sections.

[0060] Fig. 5 serves to illustrate a method according to the invention for controlling a positioning device according to the invention with two pairs of drive units arranged opposite one another with respect to a circumference BU, i.e. two pairs of drive units, for realizing rotary movements about the rotation axis RA, which is arranged substantially perpendicular to the two orthogonal movement axes BA1 and BA2. The schematically shown base 2 can be seen with a circular shape, in which a total of four individual drive units 3 are arranged equidistantly, i.e. at an angular distance of 90°, along a likewise circular circumference BU of the base 2, which has a smaller radius than the outer circumference of the base 2 (according to Figures 4a) and b)).

[0061] The two drive units forming a corresponding drive unit pair, which are arranged opposite one another along the y-axis or along the movement axis BA2 with respect to the circumference BU, are designated "A", while the two drive units forming a corresponding drive unit pair, which are arranged opposite one another along the x-axis or along the movement axis BA1 with respect to the circumference BU, are designated "B". These designations "A" and "B" are used to assign the movements or positions of a friction element of the different drive unit pairs "A" and "B" relative to the rotor 8 at different or subsequent times of rotational drive steps, as shown schematically in Fig. 5b) in illustrations i) to vii).Identical marking of both drive units of a drive unit pair also indicates that these drive units are controlled identically.

[0062] To implement a rotational movement of the rotor 8 shown in Fig. 5b), the drive unit pair "A" is controlled such that at least one component of the resulting movement of its friction elements is directed in the same direction with respect to or along the circumference BU of the base 2 and in the opposite direction or opposite to each other with respect to the movement axis BA1 or the x-axis. Similarly, the drive unit pair "B" is controlled such that at least one component of the resulting movement of its friction elements is directed in the same direction with respect to or along the circumference BU of the base 2 and in the opposite direction or opposite to each other with respect to the movement axis BA2 or the y-axis, wherein the control of the different drive unit pairs "A" and "B" is phase-shifted from one another, as can be seen from the illustrations i) to vii) of Fig. 5b).However, illustrations i) to vii) only illustrate the movements of one of the friction elements of the corresponding drive unit pair, since – as explained above – the movements of the friction elements of a drive unit pair are directed in opposite directions or opposite to each other with respect to the movement axes BA1, BA2, or with respect to the x and y axes. Accordingly, with reference to illustrations i) to vii) of Fig. 5b), the movements of the respective other friction element of the drive unit pairs "A" and "B" would have to be represented as a mirror image.

[0063] In a first phase of a drive step according to illustration i) of Fig. 5b), the friction elements of the drive unit pair "B" are in frictional contact with the rotor 8, while the friction elements of the drive unit pair "A" are lifted off the rotor and thus out of contact with it. As mentioned, Fig. 5b) to directly determine only the movement or current position of one friction element of a pair of drive units, while the other friction element performs a mirror-image or essentially mirror-image movement, which is not shown for reasons of clarity.

[0064] According to illustration ii) of Fig. 5b), in a phase following the phase according to illustration i), the friction elements of the drive unit pair “B” move in a direction that runs along the circumference BU and corresponds to a circumferential direction with respect to the circumference BU while maintaining frictional contact with the rotor 8, wherein the two friction elements of the drive unit pair “B” perform a movement in the same direction with respect to the circumference BU, so that a corresponding rotational drive of the rotor 8 and thus of the platform of the positioning device (not shown in Fig. 5b) occurs. In the same temporal phase according to illustration ii), the friction elements of the drive unit pair “A” move in a direction towards the rotor 8, whereby they approach the rotor 8, wherein a component of the corresponding movement changes in a direction opposite to or parallel to the drive movement of the friction elements of the drive unit pair “B”.opposite direction. As a result of the continuation or continuation of this movement of the friction elements of the drive unit pair “A”, they come into frictional contact with the rotor according to illustration iii) in a phase which follows the phase according to illustration ii), and this preferably at a position which corresponds to the maximum achievable position along the circumferential direction due to the geometric and physical conditions with regard to a drive unit and in particular its actuators. At the same time or essentially at the same time, the friction elements of the drive unit pair “B” reachcontinued movement in a direction which runs along the circumference BU and corresponds to a circumferential direction with respect to the circumference BU, a position which preferably corresponds to a maximum achievable position along the circumferential direction due to the geometric and physical conditions with respect to a drive unit and in particular its actuators.

[0065] Subsequently, the friction elements of the drive unit pair "B" are lifted off or released from the rotor 8 and, in the lifted state, perform a movement opposite to the drive movement as shown in illustration iv), while - as can be seen there - the friction elements of the drive unit pair "A", in frictional contact with the rotor, perform a movement in a direction that runs along the circumference BU and corresponds to a circumferential direction with respect to the circumference BU. The two friction elements of the drive unit pair "B" perform a movement in the same direction with respect to the circumference BU, so that the corresponding rotary drive of the rotor 8 and thus of the platform of the positioning device not shown in Fig. 5b).

[0066] According to representation v) of Fig. 5b), the positions of the friction elements of the drive unit pairs “A” and “B” correspond in an interchanged form to the positions of the friction elements according to representation i), i.e. the friction elements of the drive unit pair “B” now have the position of the friction elements of the drive unit pair “A” according to representation i), and the friction elements of the drive unit pair “A” now have the position of the friction elements of the drive unit pair “B” according to representation i). In the following phases shown in representations vi) and vii), the friction elements carry out the movements described for representations ii) and iii), only in an interchanged manner, until, after appropriate continuation, the exact constellation according to representation i) results again, and the aforementioned sequence is repeated until the target position of the rotor 8 or the platform connected to it is reached.

[0067] Figures 6a)-c) serve to illustrate a method according to the invention for controlling a positioning device according to the invention for implementing movements of the platform (not shown in Fig. 6) along two orthogonal axes of movement, which, in contrast to Fig. 4, has not two, but three pairs of drive units arranged opposite one another with respect to a circumference, i.e. three drive unit pairs. The two associated drive units of a drive unit pair, each arranged opposite one another with respect to the circumference BU, are labeled "A" and "B", and the corresponding drive unit pairs are also referred to as "A" and "B" hereinafter. The same or identical labeling of both drive units of a drive unit pair also expresses that these drive units are controlled identically.

[0068] From the above, it follows that there is one drive unit pair "A" and two drive unit pairs "B", and thus a total of six drive units "A" and "B" arranged along the circumference BU of the base 2. Fig. 6a) in combination with Fig. 6c) shows that the drive unit pair "A" is responsible for movements in or along the x-direction. For this purpose, the drive units "A" are controlled in all phases of a drive step in such a way that their friction elements - as can be seen from Fig. 6c) - move synchronously in the same direction and in the same direction in order to jointly drive the platform in the x-direction through the corresponding synchronous movement, while the drive units "B" are controlled in all phases of a drive step in such a way that their friction elements move synchronously in the same direction and in the same direction in order to the corresponding synchronous movement, which differs from the direction of movement or movement trajectory of the friction elements of the drive units “A”, to support the drive process generated by the drive units “A” without itself providing a drive in or along the drive direction of the platform. The movement or position of the friction elements of the drive unit pairs “A” and “B” shown in Fig. 6c) and the respective underlying electrical control does not differ from the movement of the friction elements or control of the drive units described above for Fig. 4c), which is why a detailed description is omitted here to avoid repetition. This applies in particular with regard to the two drive unit pairs “A” and “B” which are identical or identically arranged to Figures 4a) and b), which are arranged along orare arranged on the x-axis (drive unit pair “B”) and the y-axis (drive unit pair “A”).

[0069] The further drive unit pair “B” according to Figures 6a) and b), which is additionally present compared to Figures 4a) and b) and whose respective drive unit “B” is located between the two respective drive units of the drive unit pairs “A” and “B” arranged along the x- and y-axes, is controlled in an identical way to the drive unit pair “B” arranged along the x-axis, whereby - as already described for Figure 4 - the drive unit pairs “B” do not have the function of generating a drive, but rather of supporting the movement of the platform generated by the drive unit pair “A”. This support is provided by the fact that, due to the corresponding movement of the friction elements of the drive units “B”, these ensure, by means of a friction contact, that the rotor 8 is clamped after a drive step generated by the friction elements of the drive units “A”, and thus the reached position of the rotor 8 orthe platform, and release this clamping or fixing for a subsequent drive step to be generated by the drive units "A" by lifting off the runner 8 or its friction element and removing the frictional contact. By using four drive units "B" acting as described above instead of two according to Figures 4a) and b), a higher clamping or holding force of the runner can be generated.

[0070] As already described in Fig. 4, it is also possible, in a modification of the method outlined in Fig. 6, to control, for example, the drive units “B” in such a way that they counteract any parasitic movements of the rotor 8 or the platform connected to it caused by the drive of the drive units “A”. In addition, the drive units “B” can also be controlled alternately with the drive units “A” in such a way that a diagonal travel or diagonal movement of the rotor 8 and thus of the platform results. Many other different or temporally offset and possibly Overlapping controls of the drive units “A” and “B” to meet different requirements with regard to the positioning device and in particular its positioning accuracy and / or speed are also conceivable.

[0071] The only difference between Fig. 6a) and Fig. 6b) is that in Fig. 6b) the drive units marked with "A" or the corresponding drive unit pair "A", which are arranged along the x-axis in opposite directions with respect to the circumference BU, are now responsible for a movement of the rotor 8 or the platform in or along the y-axis and are controlled accordingly, while the drive unit pair "B" arranged along the y-axis in opposite directions with respect to the circumference BU and the further drive unit pair "B" are controlled in such a way that they do not make an active contribution to the drive movement generated by the drive unit pair "A", but rather - as described above for Fig. 6a) - support the drive movement by alternately clamping and releasing the rotor.

[0072] Fig. 7 serves to illustrate a method according to the invention for controlling a positioning device according to the invention with three pairs of drive units 3 arranged opposite one another with respect to a circumference BU, i.e. three pairs of drive units, for implementing rotary movements about the axis of rotation RA, which is arranged essentially perpendicular to the two orthogonal axes of movement BA1 and BA2. Fig. 7a) shows the schematically shown base 2 with a circular shape, in which a total of six drive units 3 are arranged along a likewise circular circumference BU of the base 2, which has a smaller radius than the outer circumference of the base 2, in a manner identical to that shown in Figs. 6a) and b).

[0073] The two associated drive units, which are arranged opposite one another with respect to the circumference BU, are each labeled "A" and "B", whereby this label serves to assign the movements or positions of a friction element of the different drive units "A" and "B" at different or subsequent times of rotational drive steps, as shown schematically in Fig. 7b) in the individual illustrations i) to vii). The different labeling of the two drive units of a drive unit pair expresses that these drive units are controlled differently and, in particular, out of phase with one another, whereas an identical or identical labeling of the drive units arranged along the circumference BU expresses that the respective drive units are controlled identically.

[0074] To realize a rotational movement of the rotor shown in Fig. 7b), all three drive units “A” are controlled in an identical and synchronous manner in such a way that at least one component of the resulting movement of its friction elements is directed in the same direction with respect to or along the circumference BU of the base 2, i.e. either clockwise or counterclockwise with respect to the circumference BU. All three drive units “B” are also controlled in an identical and synchronous manner such that at least one component of the resulting movement of its friction elements is directed in the same direction with respect to or along the circumference BU of the base 2, with the control of the drive units “A” and “B” being phase-shifted to one another, as can be seen from illustrations i) to vii) of Fig. 7b). However, illustrations i) to vii) only illustrate the movements of one of the friction elements of the corresponding drive unit. For details regarding the individual phases of the phase-shifted movement of the friction elements of the drive units “A” and “B” according to illustrations i) to vii) of Fig.7b) reference is made to the corresponding description of Fig. 5b), which is also applicable here.

[0075] Fig. 8 serves to illustrate a method according to the invention for controlling a positioning device according to the invention for realizing movements along the two orthogonal axes of movement BA1, BA2, wherein three pairs of oppositely arranged drive units, i.e. three pairs of drive units, are arranged with respect to a first, larger or outer circumference BU1, this arrangement corresponding to the arrangement of the three drive unit pairs according to Figs. 6a) and b). In addition to the drive units mentioned above and arranged with respect to the circumference BU1, there are two pairs of oppositely arranged drive units with respect to a second, smaller or inner circumference BU2 which is concentric with the circumference BU1, so that a total of five drive unit pairs with a total of ten drive units are present.

[0076] The drive units arranged opposite one another with respect to the respective circumference BU1, BU2, which form a respective drive unit pair and which are controlled identically for a corresponding interaction, are marked "A", "B" and "C", whereby this marking is also used below for the respective drive unit pair. Accordingly, with respect to the circumference BU1, one drive unit pair "A" and two drive unit pairs "C" are arranged, while with respect to the circumference BU2, one drive unit pair "B" and one drive unit pair "C" are arranged. Explicitly, all drive units "A" are controlled identically, and all drive units "B" are controlled identically, and all drive units "C" are controlled identically.

[0077] The pair of drive units “A” arranged along the y-axis, whose drive units “A” are arranged along the larger and outer circumference BU1, is for is responsible for the movement of the runner 8 or the platform in or along the x-axis or the movement axis BA1 and is controlled in such a way that the movements of the associated friction element shown in Fig. 8c) result.

[0078] The drive unit pair "B", which is also arranged along the y-axis but whose drive units "A" are arranged along the smaller and inner circumference BU2, is equally responsible for the movement of the runner 8 or the platform in or along the x-axis or the movement axis BA1 and is controlled in such a way that the movements of the associated friction element shown in Fig. 8c) result. It can be seen that the movements or the resulting movement paths or trajectories of the friction elements of the different drive unit pairs are identical, but out of phase with each other. This results from the identical, but out of phase, control of the drive unit pairs "A" and "B".

[0079] All drive units "C", however, are controlled in such a way that they make no contribution to the drive movements generated by the drive unit pairs "A" and "B". Instead, they are controlled in such a way that an active lifting of their friction elements from the slider 8 takes place and they are thus out of contact with the slider at least while the drive unit pairs "A" and "B" are generating movement steps. The drive units "C" are distributed across a total of three corresponding drive unit pairs "C". Two of these are arranged at different positions along the outer circumference BU1, of which the drive units of one of these drive unit pairs are arranged along the x-axis, and the drive units of the remaining drive unit pair "C" are arranged along the inner circumference BU2 and lying on the x-axis.

[0080] The only difference between Fig. 8a) and Fig. 8b) is that in Fig. 8b) the drive units marked "A" and "B" or the corresponding drive unit pairs "A" and "B" are each arranged along the x-axis and are responsible for moving the slider 8 or the platform in or along the y-axis and are controlled accordingly with a phase shift. Similarly, the drive unit pairs now arranged along the y-axis and on the different circumferences BU1 and BU2 are marked "C", and all drive units "C" are controlled identically in such a way that an active lifting of their friction elements from the slider 8 takes place and they are thus out of contact with the slider at least while the drive unit pairs "A" and "B" are generating movement steps.

[0081] Of course, it is also conceivable that the drive units “C” or the drive unit pairs “C” are controlled in such a way that they contribute to the The parasitic movements contribute to the drive movement of the rotor, both in phase and out of phase, to the control of drive unit pairs "A" and / or "B." Furthermore, it is conceivable to control drive unit pairs "C" in which these parasitic movements counteract any parasitic movements generated by drive unit pairs "A" and "B."

[0082] Fig. 9 serves to illustrate a method according to the invention for controlling a positioning device according to the invention for realizing rotary movements about the rotation axis RA, which is arranged substantially perpendicular to the two orthogonal movement axes BA1 and BA2, with three pairs of drive units 3 arranged opposite one another with respect to a first and larger or outer circumference BU1, ie three pairs of drive units with respect to the circumference BU1, and with two pairs of drive units 3 arranged opposite one another with respect to a second and smaller or inner circumference BU2 (according to Figures 8a) and 8b)).

[0083] The drive units of the three drive unit pairs arranged with respect to the circumference BU1 are each marked “A” and “B”, whilst all drive units of the two drive unit pairs arranged with respect to the circumference BU2 are provided with the same marking “C”. This marking serves to assign the movements or positions of a friction element of the different drive units “A”, “B” and “C” at different or subsequent times of rotary drive steps, as shown schematically in the individual illustrations i) to vii) in Fig. 9b). The different markings of the drive units serve to better differentiate and also expresses that differently marked drive units are also controlled unequally and in particular out of phase with one another, whilst an identical orIdentical marking of drive units indicates that the respective drive units are controlled identically.

[0084] To realize a rotational movement of the rotor shown in Fig. 9b), all three drive units "A" arranged along the circumference BU1 are controlled in an identical and synchronous manner such that at least one component of the resulting movement of their friction elements is directed in the same direction with respect to or along the circumference BU1, i.e. either clockwise or counterclockwise with respect to the circumference BU. All three drive units "B" arranged along the circumference BU1 are also controlled in an identical and synchronous manner such that at least one component of the resulting movement of its friction elements is directed in the same direction with respect to or along the circumference BU1, wherein the control of the drive units "A" and "B" is phase-shifted to one another. as can be seen in the illustrations i) to vii) of Fig. 9b). However, the sketches i) to vii) only illustrate the movements of one of the friction elements of the corresponding drive unit.

[0085] All drive units “C” are controlled identically in such a way that an active lifting of their friction elements from the rotor 8 takes place and they are thus out of contact with the rotor at least during the generation of alternating movement steps by the drive unit pairs “A” and “B”, as can be clearly seen from Fig. 9b).

[0086] It is of course conceivable that the drive units “C” or the drive unit pairs “C” are also controlled in such a way that they contribute to the rotary drive movement of the rotor, both in phase and out of phase with the control of the drive unit pairs “A” and / or “B”.

[0087] A variety of further embodiments of the positioning device according to the invention and the corresponding method for its operation are conceivable. In particular, it is conceivable that, in a modification to the embodiment according to Figs. 6 and 7, more than three drive unit pairs are provided, the drive units of which are arranged along the circumference BU. Furthermore, it is conceivable that, in a modification to the embodiment according to Figs. 8 and 9, further drive unit pairs are provided, the drive units of which are arranged along the circumference BU1 and / or along the circumference BU2. Furthermore, it is conceivable here that further drive unit pairs are provided, the drive units of which are arranged along further circumferences, iealong more than two different circumferences, wherein the drive units which are arranged along the same radial direction on different circumferences form a respective drive unit group, and the drive units of a drive unit group are controlled in a phase-shifted manner with respect to one another, in particular for the realization of translational movements.

[0088] List of reference symbols 1 Positioning device 2 Actuator 3 Drive unit 4 Actuator 5 Friction element 6 Storage 7 Platform 8 runners 9 Friction element 10 spring element 62 flat sliding guide element 63 Sliding guide component 64, 66 Linear bearings 68 rotary bearings 82 Shaft (of the rotor 8) 84 Cantilever section (of rotor 8) BA1, BA2 movement axes BE movement plane BU, BU1 , BU2 scope (of base 2) RA rotation axis

Claims

Claims 1. Positioning device (1) comprising a base (2); at least four electromechanical drive units (3) arranged in pairs opposite one another along a circumference (BU) of the base (2) and mechanically connected to the base, which drive units form a first and a second pair of drive units, each drive unit (3) having two actuators (4) which are deflectable by appropriate control and arranged in a V-shape relative to one another, and a friction element (5) connecting the two actuators to one another; a platform (7) which is movably mounted relative to the base (2) via a bearing (6) at least along two mutually orthogonal axes of movement (BA1, BA2) in a plane of movement (BE) spanned by these axes, the platform being designed as an element to be driven or as a connection point for fastening an element to be driven;a rotor (8) coupled to the platform (7) and driven by the drive units (3), said rotor comprising a friction element (9) and a spring element (10), wherein the spring element (10) presses the friction element (5) of a drive unit (3) against the friction element (9) in such a way that, when the actuators (4) are not deflected, said friction element is in contact with the friction element (9) and, when deflected, can cause at least one of the other friction elements (5) to be mechanically lifted off the friction element (9), wherein, by appropriately controlling the respective drive unit (3) and by the resulting deflection of its actuators (4), a movement of the respective friction element (5) results with movement components arranged parallel to the movement plane (BE), and thereby positioning movements of the platform (7) can be realized at least linearly along the two orthogonal movement axes (BA1, BA2); 2. Positioning device (1) according to claim 1, wherein the spring element (10) defines a spring axis, along the direction of which the spring element (10) provides a spring travel due to a respective change in length thereof, wherein the positioning device (1) is configured such that by appropriately controlling respective drive units (3), a deflection of their actuators (4) and a movement of the respective friction elements (5) with movement components arranged parallel to the movement plane (BE) and thereby one or both of the following actuating movements (M1), (M2) of the platform (7) takes place: (M1) a linear actuating movement along two mutually orthogonal movement axes (BA1, BA2), which each run transversely to the spring axis, (M2) a rotation about a rotation axis (RA), which runs along the spring axis.

3. Positioning device (1) according to one of the preceding claims, wherein the bearing (6) additionally allows rotation of the platform (7) in the plane of movement (BE) about a rotation axis (RA) running perpendicular to the plane of movement (BE).

4. Positioning device (1) according to one of the preceding claims, wherein the bearing (6) is realized by a sliding bearing and preferably has a flat sliding guide element (62).

5. Positioning device (1) according to claim 4, wherein the sliding bearing comprises a planar sliding guide element (62) which is arranged between the base (2) and the platform (7) and is in frictional contact with the platform (7).

6. Positioning device (1) according to one of claims 1 to 3, wherein the bearing (6) comprises two separate linear bearings (64, 66) for separately guiding the movement of the platform (7) in the movement plane (BE) along each of the aforementioned orthogonal movement axes (BA1, BA2).

7. Positioning device (1) according to claim 6, wherein the bearing (6) for enabling the rotational movement of the platform (7) about the rotation axis (RA) is realized by a rotary bearing (68), preferably in the form of a rolling bearing, wherein the rotary bearing (68) is mechanically connected to one of the two separate linear bearings (64, 66).

8. Positioning device (1) according to one of the preceding claims, wherein the drive units (3) between the base (2) and the friction element (9) of the rotor (8) are arranged and the spring element (10) of the rotor (8) is connected to the platform (7) in such a way that the platform (7) is decoupled from movements of the friction elements (5) in a direction which is arranged perpendicular or substantially perpendicular to the plane of movement (BE).

9. Positioning device (1) according to one of claims 1 to 7, wherein the spring element (10) of the rotor (8) is connected to the platform (7) indirectly via a sliding guide component (63) which is at least partially flat and via the friction element (9), wherein the sliding guide component (63) is pressed against the friction element (9) by means of the spring element (10) and this against the friction elements (5), and the friction element (9) is mechanically connected to the platform (7), whereby a linear movement of the platform (7) in a direction perpendicular to the movement plane (BE) as well as tilting movements about the two orthogonal movement axes (BA1, BA2) can be realized.

10. Positioning device (1) according to claim 9, wherein the sliding guide component (63) is arranged at least in sections between the friction element (9) and the platform (7) and at a distance therefrom.

11. Positioning device (1) according to one of the preceding claims, wherein the actuators (4) comprise and preferably consist of an electromechanical material.

12. Positioning device (1) according to claim 11, wherein the actuators (4) consist of piezoelectric and preferably piezoceramic material.

13. Positioning device (1) according to one of the preceding claims, wherein it has a device for recording and processing measurement or operating data relevant to the state of the positioning device (1), which device is designed to record and process the measurement or operating data during the running time of the positioning device (1) and optionally to link them together, so that an image of the state of the positioning device (1) can be derived therefrom.

14. Method for operating the positioning device according to one of the preceding claims, wherein, in order to realize movements of the platform along the orthogonal axes of movement (BA1, BA2) in the plane of movement (BE), the respective pair of drive units is controlled in such a way that at least one component of the resulting movement of its friction elements (5) is rectified and runs along or parallel to the corresponding axis of movement (BA1, BA2).

15. A method for operating the positioning device according to claim 14, wherein at least two pairs of drive units are arranged at least along two different circumferences (BU1, BU2) of the base (2), and to realize movements of the platform (7) along the orthogonal axes of movement (BA1, BA2) in the plane of movement (BE), the respective pair of drive units arranged along one of the circumferences (BU1, BU2) is controlled in such a way that at least one component of the resulting movement of its friction elements (5) is directed in the same direction and runs along or parallel to the corresponding axis of movement (BA1, BA2), and the other pair of drive units responsible for the movement of the platform (7) along the same axis of movement (BA1, BA2) and arranged along the respective other circumference (BU1, BU2) is controlled in such a way,that at least one component of the resulting movement of its friction elements (5) is rectified and runs along or parallel to the corresponding movement axis (BA1, BA2), wherein the control of the different drive unit pairs is phase-shifted to one another.

16. A method for operating the positioning device according to claim 14 or 15, which additionally allows a rotational movement of the platform (7) about a rotation axis (RA) running perpendicular to the plane of movement (BE), wherein, to realize the rotational movement, at least one of the drive unit pairs is controlled such that at least one component of the resulting movement of its friction elements is in the same direction with respect to a circumference (BU) of the base (2), and at least one other of the drive unit pairs is controlled such that at least one component of the resulting movement of its friction elements is in the same direction with respect to a circumference (BU) of the base (2), wherein the control of the different drive unit pairs or the control of the drive units of a drive unit pair takes place out of phase with respect to one another.

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