6-Axis Positioning System with Locking Component

Abstract

The present invention relates to a six-axis positioning system (1), comprising a base (2), a movable unit (3) and six variable-length actuators (5.1, 5.2, 5.3; 7.1, 7.2, 7.3), one end (8) of each actuator being connected to the base (2) and the other end (9, 14) of each actuator being connected to the movable unit (3). At least one additional member (16) of variable length is provided, one end (8, 12) of which is connected to the base (2) and the other end (9, 14) of which is connected to the movable unit (3). The additional member (16) is designed such that the six-axis positioning system (1) can be releasably locked in at least some positions of the movable unit by means of the additional member. A system of this type should be able to achieve more favorable precise positioning. For this purpose, the additional member (16) has a releasable locking actuator (19), and the variable-length member (16) is designed such that its length can be changed passively by the movement of the six driven actuators (5.1, 5.2, 5.3; 7.1, 7.2, 7.3). The present invention also relates to a corresponding method for operating the six-axis positioning system (1).

Description

Technical Field

[0001] The present invention relates to a six-axis positioning system, including a base, a movable unit, and six variable-length actuators. One end of each actuator is connected to the base, and the other end of each actuator is connected to the movable unit. At least one additional member with variable length is provided, one end of which is connected to the base and the other end of which is connected to the movable unit. The additional member is designed such that the six-axis positioning system can be releasably locked in at least some positions of the movable unit by means of the additional member. Background Art

[0002] Such a six-axis positioning system is also known as a hexapod, providing six degrees of freedom of movement in a compact space. The movable unit typically consists of a platform (movable unit) connected to the upper ends of the actuators, on which the element or attachment to be positioned is arranged. The six-axis positioning system can be obtained in different sizes and has a wide range of applications. As a component in industrial production processes, the hexapod can position high loads with sub-micron accuracy. For industrial applications, there is a combination of absolute measurement position sensors, suitable software, and motion controllers that allow even complex motion profiles to be conveniently executed. The preferred drive for the actuators is a brushless DC motor with a brake. The working space of such a six-axis positioning system is highly dependent on the length of the deployment ("telescoping") of the actuators. In particular, in the case of a heavy-load six-axis positioning system, very large actuators are used to provide the necessary rigidity. This increases the installation space and the cost.

[0003] A general positioning system is known from DE102004004313A1. Among other things, a layout is described therein, having six telescopically length-adjustable rod elements and three additional rod-shaped strengthening elements. All elements extend from a base element to a working element. It is further explained that stiffening or strengthening is mainly achieved in the working position, while the stiffening or strengthening effect is reduced in the transition positions between the initial position and the working position. The detailed manner of performing the strengthening is not described in detail. However, generally speaking, the strengthening elements can be adjusted in their length in a controllable or adjustable manner. It can be actuated hydraulically, pneumatically, mechanically, or electrically. Alternatively, or in addition to the strengthening elements, prestressing elements are also mentioned.

[0004] DE102006011823A1 relates to a positioning device having a base plate and a tool plate connected to each other by means of six struts. The struts are combined into strut pairs, and the strut pairs can have at least a common linkage mechanism, a common drive, and a common braking mechanism at the base plate.

[0005] DE10255950A1 relates to a robot drive having two partial drives dedicated to corresponding tasks. These are a partial drive for generating force and a partial drive for generating positioning. In a specific case (see Figures 1 and 2), the robot arm is provided with a power drive, which consists of an electric motor with a gearbox and an open toothed belt. The toothed belt is pre-tensioned by a tension spring. In addition, a positioning drive is provided, which consists of a conventional DC micro-motor with an angle encoder and a high reduction gear. A coupling provides an appropriate coupling between the two partial drives. A locking brake, such as a piezo-actuated brake, which is assigned to the positioning drive, is also described.

[0006] CN107538231A1 relates to a multi-axis positioning device, including a lower platform, an upper platform, six actuators arranged obliquely, and three support columns arranged in the center. The load is mainly borne by the support columns. The support columns include linear guides, at the upper end of which a hinge device is connected to the upper platform. A linear bearing is supported on the base by means of a compression spring. The base is located and fixed on the lower platform, while the upper part of the support column can move freely relative to the lower platform. Six actuators provide precise control. Summary of the Invention

[0007] Therefore, the problem of the present invention is to provide a 6-axis positioning system of the above type, which provides simplified locking, especially at the target position, with high precision and even with an increased load.

[0008] In a general 6-axis positioning system, an additional component has a releasable locking brake for this purpose, and the additional component is designed to be passively variable in length by moving six driven actuators. The additional component is designed such that the 6-axis positioning system can be releasably locked in at least some positions of the moving unit by means of the additional component. The additional component of variable length is understood to be an element, component, etc. in addition to the six actuators. Thus, in addition to any locking devices or brakes that may be present on the six actuators, at least one additional component of variable length is a necessary thing to be present on the 6-axis positioning system. The additional component also offers the advantage that it can be placed at a different position from the actuators, such that due to the grouping of at least one additional component, the distance from the center, etc., a significant impact can be exerted on the reinforcement of the entire system caused by the locking. Therefore, such an arrangement is also particularly suitable for heavy-load 6-axis positioning systems, since usually large-sized heavy-load actuators have to be used. Among other things, this results in the following advantage: By means of additional simple measures, compliance with the target position can be achieved in a more cost-effective manner due to higher rigidity. The additional component does not actively participate in the positioning of the moving unit, but instead ensures locking in a predetermined target position by means of the locking brake. Therefore, when the moving unit moves, the additional component behaves passively, since they are pulled or moved along by the actuators. Thus, the additional component of variable length does not have its own drive, which results in a cost reduction. Providing the locking brake in an additional component of variable length in a completely passive configuration also has the advantage of greatly improving the accuracy of the entire 6-axis positioning system. Due to the six variable-length actuators, the heat generated by the locking brake has no negative impact on the drives, which enables very high accuracy to be achieved. Thus, the locking brake can be largely thermally decoupled from the drives in the six actuators. Therefore, thermal expansion has a smaller impact on the positioning accuracy.

[0009] Advantageously, the additional component is designed such that the 6-axis positioning system can be releasably locked in the entire working space of the 6-axis positioning system. Thus, at least one additional component can follow the movement of the moving unit in the working space and then lock it in the desired target position. Thus, benefits are provided throughout the working space.

[0010] According to one embodiment, the releasable locking brake is a piezoelectric brake. This can be controlled very precisely such that the braking process itself does not affect the target position.

[0011] According to a further embodiment, the releasable locking brake can be a suction brake (vacuum brake). This is very inexpensive to provide with a small amount of effort.

[0012] For reasons of symmetry in particular, according to one embodiment, it is advantageous to provide at least two, preferably three, additional components of variable length for locking a 6-axis positioning system. This variant in which one additional component is assigned to each of the two actuators is particularly advantageous. The uniform distribution also enables uniform reinforcement to be achieved in the respective working space.

[0013] Thus, the additional components can be designed to increase the rigidity and natural frequency of the 6-axis positioning system in the locked state. In particular, for heavy-duty 6-axis positioning systems, this is particularly advantageous because even high loads can be arranged with a very high positional accuracy using a more favorable 6-axis positioning system.

[0014] In particular in heavy-duty 6-axis positioning systems, very high forces typically act in the vertical direction. Thus, it is advantageous if the additional components are so length-variable and pivotally connected to the base and the movable unit that the additional components are arranged movably within an angular range of up to ±45° (preferably up to ±30°) relative to the vertical line or the perpendicular to the plane spanned by the base. In the basic position, the base and the movable unit are typically arranged horizontally, respectively, such that an angle to the reference vertical line is produced. However, in principle, the 6-axis positioning system itself can assume different angular positions, i.e., for example, the base can be tilted away from the horizontal direction, which is why the reference vertical direction is advantageous. The plane spanned by the base is given, for example, by the plane containing the center of the joint points of the additional components or the joint points of the actuators. The additional components arranged in this way have a reinforcing effect, in particular with respect to the forces mainly introduced vertically.

[0015] In another advantageous embodiment, it is provided that the six actuators are divided into two groups, the actuators of the first group being arranged in the region on the base bounded by the actuators of the second group and on the movable unit. Preferably, the actuators of different groups are also configured differently. Thus, the movable unit with an extended working space can be moved around the end of the actuators of the first group attached to the movable unit. In this way, it is possible to configure these three actuators of the first group to be shorter than the three actuators of the second group and, if required, to provide them with a greater lifting force. Thus, a division of the work between the actuators of the first group and the second group is feasible, which overall results in a more compact, in particular flatter, design with an extended working space. In addition, the additional components support the reinforcement when the desired target position is assumed.

[0016] Conveniently, at least one additional component can be located on the base and the movable unit, further out relative to the actuators of the first group, preferably in the region between the actuators of the first group and the actuators of the second group. By this, in particular, tilting forces originating outside the range supported by the three actuators of the first group are additionally supported by at least one component. Despite the greater pivoting ability achieved due to the arrangement of the actuators of the first group, stable positioning can still be achieved.

[0017] In another embodiment, it is provided that the actuators of the first group are length-variable and pivotally connected to the base and the movable unit such that each of the three actuators of the first group is movably arranged within an angular range of up to ±30°, preferably up to ±15°, relative to the vertical line or the perpendicular line to the plane spanned by the base, and the three actuators of the second group are length-variable and pivotally connected to the base and the movable unit such that each of the three actuators of the second group is movably arranged within an angular range of ≥0° to up to 45°, preferably ≥0° to up to 30°, relative to the horizontal line or the parallel line to the plane spanned by the base. This arrangement allows the main part of the load to be received by the three actuators of the first group, while the three actuators of the second group are mainly used for positioning. With the corresponding change in the actuator length, the ratio then changes, and the main lifting load is still carried by the three actuators of the first group. At least one additional component is then stabilized in the corresponding target position. Due to the angular specifications, the three actuators of the second group are generally arranged flatter than the three actuators of the first group.

[0018] In its extreme case, the three actuators of the second group can thus be positioned flat or horizontally in the minimum stroke position and at an acute angle in the maximum stroke position. Overall, this results in a very flat and compact design. In this arrangement, the three actuators of the second group require a higher positioning path. This is only possible if these three actuators move laterally past the three actuators of the first group. There can also be a passage through at least one additional component, or a space can be left between the three actuators of the second group for placing at least one additional component.

[0019] Preferably, the three actuators of the first group can be configured as heavy-load actuators with a greater load capacity than the three actuators of the second group. Although standard and identical components can also be used, it is preferred that the three actuators of the first group and the three actuators of the second group are configured differently. There is the feasibility that the three actuators of the first group are at least twice, further preferably at least three times, the load strength of the actuators of the second group.

[0020] Furthermore, the present invention relates to a method of providing a 6-axis positioning system, the system comprising a base, a movable unit, and six variable-length actuators. One end of each actuator is connected to the base, and the other end of each actuator is connected to the movable unit. The method comprises the following steps:

[0021] Moving the movable unit relative to the base to a predetermined target position by the interaction of the six variable-length actuators, and

[0022] Locking the 6-axis positioning system so as to increase the rigidity and natural frequency of the 6-axis positioning system at the target position by means of at least one additional component. Except for the actuators, the additional component is arranged between the base and the movable unit in a variable-length manner.

[0023] Thus, the six actuators themselves do not have to be configured such that they provide the necessary rigidity and natural frequency of the system at the specified target position, but rather the actuators can be adapted accordingly relative to at least one additional component used, since the increase in rigidity and natural frequency at the target position occurs by means of at least one additional component. Thus, more complexly configured actuators can be cheaper or used in more unusual groupings without compromising the necessary rigidity and natural frequency of the target position in the workspace.

[0024] Preferably, when the movable unit is moved by the interaction of the six variable-length actuators, the additional component can move passively with the movable unit. Thus, since the movement of the movable unit is reserved for the six variable-length actuators, dragging or telescoping is achieved without significant resistance or support. However, there is at least one additional possibility for the movable unit to provide damping. However, the main purpose of the movable unit is to lock it in the target position and increase the rigidity and natural frequency of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Hereinafter, exemplary embodiments of the present invention will be explained in more detail with reference to the drawings. The sole drawing shows a perspective view of an embodiment of a 6-axis positioning system according to the present invention. DETAILED DESCRIPTION

[0026] The first embodiment of the six-axis positioning system 1 shown in the figure has a base 2 in the form of a triangular platform and a movable unit 3 also in the form of a triangular platform, as well as actuators arranged between them, which will be described in more detail below. Each of the base 2 and the movable unit 3 is formed by a plate of substantially uniform thickness, preferably formed of a metal such as steel. The actuators arranged between the base 2 and the movable unit 3 are grouped into a first group 4 including actuators 5.1, 5.2 and 5.3 and a second group 6 including actuators 7.1, 7.2 and 7.3. The actuators 5.1, 5.2 and 5.3 are different in function and structure from the actuators 7.1, 7.2 and 7.3, while the actuators of the corresponding group 4 or 6 have the same structure. The actuators 5.1, 5.2 and 5.3 of the first group 4 are pivotally arranged on the base 2 at their lower ends 8 and their upper ends 9 are pivotally arranged on the movable unit 3. The pivotal arrangement is, for example, in the form of a universal joint (cardan joint), such that a pivotal movement about two axes is feasible. For a more compact arrangement, the base 2 has window recesses 10 for mounting the lower ends 8 of each of the actuators 5.1, 5.2 and 5.3, such that the axes of the universal joints are mounted within the window recesses 10. Similarly, the movable unit 3 is provided with three window recesses 11 for the pivotal arrangement of the upper ends 9 of the actuators 5.1, 5.2 and 5.3. Again, the axes of the corresponding universal joints are fixed within the window recesses 11.

[0027] The lower ends of the actuators 7.1, 7.2 and 7.3 are pivotally arranged on corresponding bearing blocks 13, which are arranged on the base 2. For the pivotal arrangement, a universal joint is again preferably used for pivoting about two axes. In a similar manner, the upper ends 14 of the actuators 7.1, 7.2 and 7.3 are arranged by means of bearing blocks 15 attached to the movable unit 3. Also at the upper ends 14, the pivotal arrangement is preferably by means of a universal joint pivoting about two axes.

[0028] Due to the selected arrangement, the actuators 5.1, 5.2, and 5.3 of the first group 4 are arranged more upright than the actuators 7.1, 7.2, and 7.3 of the second group 6. Also helpful for this arrangement are the window recesses 10 and 11 and the two bearing seats 13 and 15. Each of the window recesses 10 and 11 is located more internally in the base 2 or the movable unit 3 compared to the respective bearing seat 13 or 15. Thereby, the actuators 5.1, 5.2, 5.3 of the first group 4 are arranged in the area defined by the actuators 7.1, 7.2, 7.3 of the second group 6 on the base 2 or the movable unit 3. Since the load is applied from above via the movable unit 3, it is also feasible that the main load is borne by the actuators 5.1, 5.2, 5.3. These actuators are thus constructed as heavy-duty actuators with a much higher load capacity than the three actuators 7.1, 7.2, 7.3 of the second group 6. The length of all 6 actuators is adjustable (telescopic) and is driven by brushless DC motors. The basic operation and control of the 6-axis positioning system are themselves known and will not be discussed in more detail here. In any case, the movable unit 3 can be raised, lowered, or displaced relative to the base 2 and tilted about all three spatial axes. The adjustability of the actuators 5.1, 5.2, 5.3 and 7.1, 7.2, and 7.3 and their arrangement determine the possible working space. Due to the drive technology used, there is very precise control and positioning even in the current heavy-load area.

[0029] Supplementing the actuators 5.1, 5.2, 5.3 and 7.1, 7.2, 7.3, three additional components 16 of variable length in the form of telescopic units are provided. Similar to the actuators 5.1, 5.2, 5.3 and 7.1, 7.2, and 7.3, the components 16 are arranged evenly or symmetrically on the base 2 and the movable unit 3. The lower end 17 of the component 16 is pivotally mounted to the base 2, and the upper end 18 is pivotally mounted to the movable unit 3. This occurs in a manner similar to the actuators 5.1, 5.2, 5.3 of the first group 4, for example, in the manner of a universal joint (cardan joint), such that pivotal movement about two axes is feasible. The additional components 16 are provided with locking brakes 19 (e.g., piezoelectric brakes or vacuum brakes) by means of which they can be locked or unlocked at any time. Otherwise, when the locking brake 19 is open, the additional components 16 freely change their length without significant resistance, and the change in length is passive due to the actuation of the actuators 5.1, 5.2, 5.3 and 7.1, 7.2, 7.3.

[0030] In the basic position of the 6-axis positioning system 1 shown in the figure, the base 2 and the movable unit 3 are aligned parallel to each other, that is, the actuators 5.1, 5.2, and 5.3 of the first group 4 have the same length, and the actuators 7.1, 7.2, and 7.3 of the second group 6 have the same length. In addition, the actuators 5.1, 5.2, and 5.3 are in their fully retracted positions, which is why the actuators 7.1, 7.2, and 7.3 also take their pivot positions as far down as possible. In this basic position, the actuators 5.1, 5.2, and 5.3 are precisely vertically aligned with their main axes, that is, they are perpendicular to the plane spanned by the base 2. In this position, the actuators 7.1, 7.2, and 7.3 have an angle of approximately 0° relative to the horizontal line or a parallel line to the plane spanned by the base 2.

[0031] The component 16 is slightly tilted out of the vertical in this position and is arranged such that its upper end 18 is closer to the upper end 9 of each of the lower actuators 5.1, 5.2, 5.3 of the first group 4 than its lower end 17 is to the lower end 8 of each of the lower actuators 5.1, 5.2, 5.3 of the first group 4. The tilt angle relative to the vertical direction is approximately 10°. In addition, the additional component 16 is placed further outwards relative to the actuators 5.1, 5.2, and 5.3 of the first group 4 on both the base 2 and the movable unit 3. However, each of these actuators 5.1, 5.2, 5.3 is assigned an adjacent partner (component 16). This arrangement is roughly in the space between the two actuators 7.1, 7.2, 7.3 of the second group 6. If the axes of the actuators 7.1, 7.2, and 7.3 of the second group 6 are extended such that they form a triangle, the actuators 5.1, 5.2, 5.3 of the first group 4 and the additional component 16 are also arranged within this triangle. This results in a compact grouping, that is, among other things, this ensures that a relatively large pivot can occur even with small strokes of the actuators 5.1, 5.2, and 5.3. However, precise positioning is feasible in the interaction of the actuators 5.1, 5.2, and 5.3 and 7.1, 7.2, and 7.3.

[0032] In the fully retracted positions of the actuators 5.1, 5.2, and 5.3 shown in the figure, the actuators 7.1, 7.2, and 7.3 of the second group 6 are much longer than the actuators 5.1, 5.2, and 5.3 of the first group 4. Therefore, the maximum adjustment path of the actuators 7.1, 7.2, and 7.3 of the second group 6 is substantially greater than the maximum adjustment path of the actuators 5.1, 5.2, and 5.3 of the first group 4.

[0033] The external components 16 are configured such that when the movable unit 3 assumes a controlled target position, these components activate the locking brake 19 by means of the actuators 5.1, 5.2, 5.3 of the first group 4 and the actuators 7.1, 7.2, 7.3 of the second group 6, thus strengthening the entire 6-axis positioning system 1 in a locking manner. This increases the overall rigidity of the system 1 and its natural frequency, enabling very accurate and enhanced positioning even during heavy-load operation.

[0034] In the following, the function and mode of operation of the illustrated embodiment are explained in more detail.

[0035] The target control of the drives of the actuators 5.1, 5.2, 5.3 and 7.1, 7.2, 7.3 results in the target positioning of the movable unit 3 relative to the base 2. The desired 6-axis positioning within a given workspace is feasible. The main load is carried by the actuators 5.1, 5.2, 5.3 of the first group 4 during lifting. Therefore, these actuators are configured as corresponding heavy-load actuators, enabling the movement of a relatively large load. The actuators 5.1, 5.2, 5.3 of the first group 4 pivot only within a limited angular range (maximum ±30°, preferably maximum ±15°) relative to the vertical line or the vertical line spanned by the base 2. The actuators 7.1, 7.2, 7.3 are also adapted to pivot only within a limited angular range (≥0° to maximum 45°) relative to the horizontal line or the parallel line P spanned by the base 2.

[0036] For example, by shortening or telescoping the actuators 7.1, 7.2, 7.3 of the second group 6 and correspondingly pivoting and extending the actuators 5.1, 5.2, 5.3 of the first group 4, the movable unit 3 can rotate relative to the base 2 without even changing the distance. Overall, the required path of the actuators 7.1, 7.2, 7.3 is greater than the required path of the actuators 5.1, 5.2, 5.3.

[0037] The variable-length additional component 16 moves passively during these positioning operations. This is done by moving together or telescoping, depending on the direction of movement. Once the desired target position has been adopted with the aid of the actuators 5.1, 5.2, 5.3 of the first group 4 and the actuators 7.1, 7.2, 7.3 of the second group 6, the locking brake 19 is set and the 6-axis positioning system 1 is locked in the target position. The component 16 is configured to significantly increase the rigidity and natural frequency of the 6-axis positioning system 1 in the target position. This is particularly necessary because in the illustrated embodiment, the actuators 5.1, 5.2 and 5.3 of the first group 4 are more centered and thus the movement of the movable unit 3 may be produced with less reinforcement. The component 16 provides appropriate compensation here, such that even heavy-load systems can operate with high precision and control their target positions. Once further movement occurs, the locking brake 19 is released again and the component 16 moves passively along. Any heat generated in the area of the locking brake 19 does not directly affect the drives of the actuators 5.1, 5.2, 5.3 of the first group and the actuators 7.1, 7.2, 7.3 of the second group. In this way, the precision is improved.

[0038] In summary, the result is that the 6-axis positioning system 1 is compact, especially flat, and able to withstand high loads with the required rigidity. This is achieved by the appropriate grouping and functional division of the two actuator groups 4, 6 and the assistance of the lockable component 16. It should also be noted that, for the sake of clarity, the presentation of the electrical connections and any other connections as well as the presentation of the sensor system have been omitted in the figures. The 6-axis positioning system 1 shown here is controlled and regulated according to the best-known procedures for this type of known system (hexapod).

[0039] List of reference signs

[0040] 1 6-axis positioning system

[0041] 2 Base

[0042] 3 Movable unit

[0043] 4 First group

[0044] 5.1, 5.2, 5.3 Actuators

[0045] 6 Second group

[0046] 7.1, 7.2, 7.3 Actuators

[0047] 8 Lower end

[0048] 9 Upper end

[0049] 10 Window recess

[0050] 11 Window recess

[0051] The lower end of 12

[0052] Bearing housing 13

[0053] The upper end of 14

[0054] Bearing housing 15

[0055] Component 16

[0056] The lower end of 17

[0057] The upper end of 18

[0058] Locking brake 19

Claims

1. A 6-axis positioning system (1) includes a base (2), a movable unit (3), and six variable-length actuators (5.1, 5.2, 5.3; 7.1, 7.2, 7.3). One end (8, 12) of each actuator is connected to the base (2), and the other end (9, 14) of each actuator is connected to the movable unit (3). At least one additional member (16) of variable length is provided, one end (17) of the variable-length additional member is connected to the base (2), and its other end (18) is connected to the movable unit (3). The variable-length additional member (16) is designed such that the 6-axis positioning system (1) can be releasably locked in at least some positions of the movable unit (3) by means of the variable-length additional member. Wherein, The variable-length additional part (16) has a releasable locking brake (19), and wherein the variable-length additional part (16) is designed such that by means of the movement of six driven variable-length actuators (5.1, 5.2, 5.3; 7.1, 7.2, 7.3), the variable-length additional part is moved passively. It is characterized in that the six variable-length actuators (5.1, 5.2, 5.3; 7.1, 7.2, 7.3) are divided into two groups (4, 6), and the variable-length actuators (5.1, 5.2, 5.3) of the first group (4) are arranged within the area defined by the variable-length actuators (7.1, 7.2, 7.3) of the second group (6) on the base (2) and are arranged on the movable unit (3), and the variable-length additional part (16) is arranged outside the area defined by the variable-length actuators (5.1, 5.2, 5.3) of the first group (4) on the base (2) and the movable unit (3).

2. The 6-axis positioning system (1) according to claim 1, characterized in that, The variable-length additional part (16) is designed such that within the entire working space of the 6-axis positioning system (1), the 6-axis positioning system can be releasably locked.

3. The 6-axis positioning system (1) according to claim 1 or 2, characterized in that, The releasable locking brake (19) is a piezoelectric brake.

4. The 6-axis positioning system (1) according to claim 1 or 2, characterized in that, The releasable locking brake (19) is a suction brake.

5. The 6-axis positioning system (1) according to claim 1, characterized in that, The number of at least one of the variable-length additional parts (16) is more than two.

6. The 6-axis positioning system (1) according to claim 5, characterized in that, The variable-length additional part (16) is designed such that it increases the rigidity and natural frequency of the 6-axis positioning system (1) in the locked state.

7. The 6-axis positioning system (1) according to claim 1, characterized in that, The variable-length additional part (16) is so length-variable and pivotally connected to the base (2) and the movable unit (3) that the variable-length additional part (16) is movably arranged within a maximum angular range of ±45° relative to the vertical line or the vertical line of the plane spanned by the base (2).

8. The 6-axis positioning system (1) according to claim 1, characterized in that, The variable-length additional part (16) is arranged on the base (2) and the movable unit (3) in the area between the variable-length actuators (5.1, 5.2, 5.3) of the first group (4) and the variable-length actuators (7.1, 7.2, 7.3) of the second group (6).

9. The 6-axis positioning system (1) according to claim 1 or 8, characterized in that, The three variable-length actuators (5.1, 5.2, 5.3) of the first group (4) are so variable in length and pivotally connected to the base (2) and the movable unit (3) that each of the three variable-length actuators (5.1, 5.2, 5.3) of the first group (4) is movably arranged within an angular range of up to ±30° relative to the vertical line or the vertical line of the plane spanned by the base (2), and the three variable-length actuators (7.1, 7.2, 7.3) of the second group (6) are so variable in length and pivotally connected to the base (2) and the movable unit (3) that each of the three variable-length actuators (7.1, 7.2, 7.3) of the second group (6) is movably arranged within an angular range of 0° to 45° relative to the horizontal line or the parallel line of the plane spanned by the base (2).

10. The 6-axis positioning system (1) according to claim 1, characterized in that, The three variable-length actuators (5.1, 5.2, 5.3) of the first group (4) are configured as heavy-duty actuators, which have a higher load capacity than the three variable-length actuators (7.1, 7.2, 7.3) of the second group (6).

Images