Multi-axis positioner
The parallel position manipulator with prism joint actuators addresses the cost and complexity issues of hexapods by enabling independent actuator movement, resulting in a cost-effective and accurate multi-axis positioning system.
Patent Information
- Application Number
- JP2025016255
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2020-09-23
- Filing Date
- 2025-02-03
- Publication Date
- 2025-04-30
- Estimated Expiration
- 2041-09-21
AI Technical Summary
Hexapods, commonly used for multi-axis positioning, are costly and require complex algorithms for actuator movement due to synergistic motion, making them impractical for simple movements and increasing costs with improved resolution.
A parallel position manipulator with a top plate, base plate, and three to six prism joint actuators, each with five degrees of freedom, allowing independent movement of actuators and reducing the need for complex algorithms.
The solution provides a cost-effective, flexible, and accurate multi-axis positioning system that allows for independent actuator movement without the constraints of hexapods, enabling precise positioning without the need for complex computational power.
Smart Images

Figure 2025069330000001_ABST
Abstract
Description
[Technical field]
[0001] The present inventive concept relates to positioning stages, and more particularly to multi-axis relative positioning stages. [Background technology]
[0002] Related Applications This application claims the benefit of U.S. patent application Ser. No. 17 / 029,908, filed Sep. 23, 2020, and entitled MULTI-AXIS POSITIONER, which is a continuation-in-part of U.S. patent application Ser. No. 16 / 930,638, filed July 16, 2020, and entitled MULTI-AXIS POSITIONER, which is a continuation-in-part of U.S. patent application Ser. No. 16 / 930,638, filed Feb. 14, 2019, and entitled MULTI-AXIS POSITIONING METHOD, now U.S. Patent No. 10,746,928. No. 10,746,928 is a continuation of U.S. Patent Application No. 15 / 720,006, now U.S. Patent No. 10,429,587, filed September 29, 2017 and entitled MULTI-AXIS RELATIVE POSITIONING STAGE, which claims the benefit of U.S. Provisional Application No. 62 / 402,674, filed September 30, 2016 and entitled MULTI-AXIS RELATIVE POSITIONING STAGE, each of which is incorporated herein by reference in its entirety.
[0003] Position manipulators are used in a vast number of applications to position objects, tools, or instruments with varying degrees of precision. An overview of the kinematic joints, or kinematic pairs, that may be used in position manipulators is shown in Figure 1, including rigid (immovable), prism, revolute, parallel cylinder, cylinder, sphere, plane, edge slider, cylinder slider, point slider, spherical slider, and cross cylinder.
[0004] A Stewart platform (also referred to herein as a hexapod) is a multi-axis positioning stage consisting of, for example, six actuators with spherical, ball, or universal joints at either end of each actuator. Hexapods are considered a world-class multi-axis positioning stage configuration for most applications, but are often cost-prohibitive. One problem with hexapods is that they are a synergistic motion platform due to the interactions between the actuators. That is, no actuator can move independently, and for a given move, many or all of the actuators must move different specific amounts and with different velocity profiles to prevent the stage from binding. Furthermore, these movements and velocity profiles change continuously as the predefined start and end points are changed. Thus, even when a short single-axis move is required, highly complex computer algorithms are required to individually calculate the movement distance and velocity profile required for each actuator to get the stage top plate from point A to point B. As a result, even this simple move cannot be manually performed by a human operator without binding the stage.
[0005] Another significant drawback with hexapods is that the stiffness of the joints (for off-axis motion) determines the "slop" or "play" and therefore the resolution of the stage. This is a design contradiction because it is exponentially more difficult to form spherical joints (employed in hexapods) with increasingly tighter tolerances. That is, if a designer were to form world-class spherical bearings to maximize the resolution of the stage and minimize tilt, they would by default exacerbate two inherent problems. First, the stiffness of the spherical joints exponentially increases the precision of the motion and velocity profile requirements of each actuator to prevent binding. Second, the functional requirements of the actuators exponentially increase to achieve the precise motion and velocity profiles required. As a result, increasing the resolution of a hexapod requires an exponential increase in the computational power to determine the motion and velocity profiles, an exponential increase in the performance capabilities of the actuators, and 12 high quality spherical bearings. All these factors drive the cost of a hexapod significantly higher.
[0006] Hexapods are generally three to ten times more expensive than their kinematic chain counterparts, but are often preferred because they do not suffer from tolerance stack-up problems. Ten-micron accuracy is not an uncommon requirement for positioners in many applications, and sub-micron accuracy is often required in the photonics industry, for example. Currently, prices for hexapods generally range from $60,000 to over $120,000, depending on the respective requirements for physical size, load limits, and accuracy. A separate precise position manipulator is highly desirable. Summary of the Invention [Means for solving the problem]
[0007] In accordance with the principles of the inventive concept, a parallel position manipulator includes a top plate, a base plate (also referred to herein as a bottom plate or base plate), and three, four, five, or six prism joint actuators. Each actuator includes an actuator joint with five degrees of freedom (DOF) on either the base plate or the top plate. In operation, as one or more of the actuators extends or contracts, the pivot point of the remaining actuator, e.g., a 5DOF actuator joint, can shift in any axis other than the axis of motion of that actuator (i.e., the axis defined by the extension and contraction of the actuator). In an exemplary embodiment, magnetic forces, gravity, and / or a flexible polymer such as silicone can be used to keep up to five DOF pivot points in contact with their respective (i.e., top or bottom) plates in the contact area as the prism actuators extend or contract. In an exemplary embodiment, at least two of the prism actuators are perpendicular to at least two other prism actuators. When a fifth axis is added, its associated prism actuator is positioned perpendicular to the other four prism actuators.
[0008] In an exemplary embodiment, the actuators may be any of several types, such as piezoelectric actuators, manual micrometer screws, magnetic actuators, stepping motors with linear actuators (either integrated or separate), hydraulic cylinders, pneumatic cylinders, or translation motors with eccentric cams, for example. In an exemplary embodiment according to the principles of the inventive concept, the parallel position manipulator is configured such that the push / pull force exerted by each actuator is greater than the shear friction of all other actuators combined. In an exemplary embodiment, this is achieved by using a material with high retention but low shear strength, such as a hard metal spherical surface held in magnetic contact with a hard flat metal surface. In such an embodiment, only one of the sides (i.e., either the hard metal spherical surface or the hard flat metal surface) is magnetized. This is because if both sides are magnetic, they are semi-constrained with a sliding axis and therefore behave like a spherical 3DOF joint.
[0009] In accordance with the principles of the inventive concept, a positioning stage includes a plurality of magnetic prism joint actuators, a base plate, and a top plate. The top plate can support a device for accurately positioning the device. The top plate can be supported by a plurality of magnetic prism joint actuators, which are in turn supported by the base plate. In an exemplary embodiment, each actuator is fixed to a portion of the base plate that positions each actuator at an angle relative to a vertical axis or plane. In an exemplary embodiment, the angle is 45 degrees, which positions the actuators at 90 degrees to each other on opposite ends or end pieces of the base plate. In an exemplary embodiment, the sides of the top plate are formed at the same angle relative to a vertical axis or plane as the sides of the base plate, although other configurations are contemplated within the scope of the inventive concept. A magnet is provided on the inclined side of the top plate. Each actuator includes a magnetic material at its distal end, which may be, for example, a ferrous metal. In an exemplary embodiment, the magnetic material is in the shape of a hemisphere, although other shapes and combinations are contemplated within the scope of the inventive concept. In a preferred embodiment, the ends of each magnetic material are configured to contact magnets on the sides of the top plate, thereby supporting the top plate above the base plate.
[0010] In operation, the distal end of the actuator is held in contact with the magnet on the side of the top plate by the force of the magnet. When the actuator is actuated (i.e., extends or retracts), the top plate moves linearly in a direction of motion determined by the movement of the actuator. The distal end of the actuator, which is in contact with the magnet on the opposite side of the top plate, remains in contact with the magnet by the magnetic force of the magnet acting on the magnetic material in the distal end of the actuator. At the same time, this distal end of the actuator allows the magnet (and top plate) to slide in a direction determined by the movement of the actuated actuator.
[0011] In accordance with an aspect of the present invention, there is provided a parallel positioner comprising a top plate, a base plate, and three or more actuators configured to support the top plate on the base plate and move the top plate in response to extension or contraction of one or more actuators, each of the actuators including a joint having five degrees of freedom.
[0012] In various embodiments, each of the actuators includes a magnetic joint as the five degree of freedom joint.
[0013] In various embodiments, the top plate includes angled sides and the actuator extends from the base plate to the top plate and is configured to support the top plate along the angled sides of the top plate.
[0014] In various embodiments, in the neutral position, the angled sides of the top plate are at the same angle relative to a vertical axis or plane as the angled sides of the base plate.
[0015] In various embodiments, each magnetic joint includes an end of an actuator formed of a hemispherical magnetic material and a magnet within the contact area of a plate.
[0016] In various embodiments, each magnetic joint is formed on a side of the top plate, an end of each respective actuator forming the joint is configured to contact a magnet on the side of the top plate, and an opposing end of each respective actuator is configured to be fixedly attached to the base plate.
[0017] In various embodiments, the parallel positioner includes four prism actuators, each forming a magnetic joint with a side of the top plate, two actuators per side, and each prism actuator fixed at its other end to a base plate, such that the end pieces of the base plate and the sides of the top plate are formed at the same angle relative to a vertical axis or plane when in a neutral position.
[0018] In various embodiments, the actuators are configured such that the same amount of extension or contraction of any pair of actuators results in movement of the top plate only along a single axis, said extension or contraction being performed under the control of an electronic controller.
[0019] According to another aspect of the inventive concept, there is provided a method of positioning a device, the method comprising the steps of providing a top plate on which the device is to be placed, providing a base plate for supporting the top plate, and providing three or more actuators between the top plate and the base plate, the actuators being configured to support the top plate over the base plate and to move the top plate by extension or contraction of one or more actuators, each of the actuators comprising a joint having five degrees of freedom.
[0020] In various embodiments, each of the actuators includes a magnetic joint as the five degree of freedom joint.
[0021] In various embodiments, the top plate includes angled sides and the actuator extends from the base plate to the top plate and is configured to support the top plate along the angled sides of the top plate.
[0022] In various embodiments, in the neutral position, the angled sides of the top plate are at the same angle relative to a vertical axis or plane as the angled sides of the base plate.
[0023] In various embodiments, each magnetic joint includes an end of an actuator formed of a hemispherical magnetic material and a magnet within the contact area of a plate.
[0024] In various embodiments, each magnetic joint is formed on a side of the top plate, with each respective actuator end of the joint configured to contact a magnet on the side of the top plate, and each respective opposite end of the actuator configured to be fixedly attached to the base plate.
[0025] In various embodiments, a method of positioning includes providing four prism actuators, each forming a magnetic joint with a side of a top plate, two actuators per side, and each prism actuator fixed at its other end to a base plate, such that the end pieces of the base plate and the sides of the top plate are formed at the same angle relative to a vertical axis or plane when in a neutral position.
[0026] In various embodiments, the actuators are configured such that the same amount of extension or contraction of any pair of actuators results in movement of the top plate only along a single axis, and said extension or contraction is performed under the control of an electronic controller.
[0027] According to another aspect of the inventive concept, there is provided a photonic positioning device comprising a photonic device, a top plate supporting the photonic device, a base plate, and three or more actuators configured to support the top plate over the base plate and move the top plate in response to extension or contraction of one or more actuators, each of the actuators including a joint having five degrees of freedom.
[0028] In various embodiments, the photonic device is an optical fiber splicer.
[0029] In various embodiments, the photonic positioning device further comprises four prism actuators, each forming a magnetic joint with a side of the top plate, two actuators per side, and each prism actuator fixed at its other end to a base plate, such that the end pieces of the base plate and the sides of the top plate are formed at the same angle relative to a vertical axis or plane when in a neutral position.
[0030] In various embodiments, the actuators are configured such that the same amount of extension or contraction of any pair of actuators results in movement of the top plate only along a single axis, said extension or contraction being performed under the control of an electronic controller.
[0031] In accordance with another aspect of the inventive concept, there is provided a parallel positioner comprising a top plate, a base plate, and at least four actuators configured to support the top plate on the base plate and move the top plate in response to extension or contraction of one or more actuators, at least some of the actuators including joints having five degrees of freedom.
[0032] In various embodiments, each of the actuators includes a joint having five degrees of freedom.
[0033] In various embodiments, not all of the actuators include joints with five degrees of freedom.
[0034] In various embodiments, at least one of the actuators includes a joint having four degrees of freedom.
[0035] In various embodiments, the top plate includes a first sloping side and a second sloping side, and the base plate includes a first sloping side piece corresponding to and parallel to the first sloping side, and a second sloping side piece corresponding to and parallel to the second sloping side.
[0036] In various embodiments, the base plate includes a middle portion from which the side pieces extend.
[0037] In some embodiments, the intermediate portion is planar.
[0038] In accordance with another aspect of the inventive concept, there is provided a positioner comprising a structure, at least one base, and a plurality of actuators configured to support the structure over the at least one base and to move the structure in response to extension or contraction of the one or more actuators, wherein three or more of the actuators maintain contact with the structure via joints having at least four degrees of freedom (DOF).
[0039] In various embodiments, three or more of the actuators include at least two actuators that maintain contact with the structure via a joint having 5 DOF.
[0040] In various embodiments, the three or more actuators include at least two actuators that maintain contact with the structure via a joint having four DOF.
[0041] In various embodiments, at least one joint having 4 DOF is a magnetic joint.
[0042] In various embodiments, at least one joint having 5 DOF is a magnetic joint.
[0043] In various embodiments, each of the three or more actuators has a magnetic joint with the structure.
[0044] In various embodiments, an actuator having a 4DOF joint with a structure has a cylindrical end that contacts the structure.
[0045] In various embodiments, the actuator having a 5DOF joint with the structure has a hemispherical end that contacts the structure.
[0046] In various embodiments, the structures include longitudinally extending grooves, depressions, or channels.
[0047] In various embodiments, the longitudinally extending groove, recess, or channel is configured to hold at least one optical fiber.
[0048] In various embodiments, the structure includes a V-groove configured to hold at least one optical fiber.
[0049] In various embodiments, the positioner further comprises a top plate, the at least one base comprises at least one base plate, and the three or more actuators supporting the top plate are coupled to the at least one base plate.
[0050] In various embodiments, the top plate includes angled sides that are engaged by a plurality of actuators, and at least one base plate includes angled side pieces to which three or more actuators are coupled, and the angled sides of the top plate and the angled side pieces of the at least one base plate have the same angle relative to a vertical plane or axis.
[0051] In various embodiments, the positioner further comprises an end plate that includes a coupling for an end of the structure.
[0052] In various embodiments, the coupling is a magnetic coupling.
[0053] In accordance with another aspect of the inventive concept, there is provided a positioner comprising a top plate, a base plate, and three or more actuators configured to support the top plate on the base plate and move the top plate in response to extension or contraction of one or more actuators, each of which maintains contact with the top plate via a joint having at least four degrees of freedom (DOF).
[0054] In various embodiments, the three or more actuators include at least two actuators that maintain contact with the top plate via a joint having 4 DOF and at least one actuator that maintains contact with the top plate via a joint having 5 DOF.
[0055] In various embodiments, the top plate includes angled sides that are engaged by three or more actuators and the base plate includes angled side pieces to which the three or more actuators are coupled, and the angled sides of the top plate and the angled side pieces of the base plate have the same angle relative to a vertical plane or axis.
[0056] In various embodiments, the actuator having a 4DOF joint with the top plate has a cylindrical end.
[0057] The present invention will become more apparent from consideration of the attached drawings and the accompanying detailed description. The embodiments illustrated therein are provided by way of example and not limitation, and like reference numerals refer to the same or similar elements. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating aspects of the invention. [Brief description of the drawings]
[0058] [Figure 1] 1A-1D illustrate various conventional kinematic joints. [Diagram 2]FIG. 1C is a front end view of an embodiment of a four-axis positioning stage or positioner with all actuators retracted, with a third actuator (not shown) behind the first actuator and a fourth actuator (not shown) behind the second actuator. [Diagram 3] FIG. 3 is the same front end view of the four-axis stage of FIG. 2, with the first actuator and the third actuator extended along an axis (the "X-axis"). [Figure 4] FIG. 3 is the same end view of the four-axis stage of FIG. 2, with the second actuator and the fourth actuator extended along an axis (the "Y-axis"). [Diagram 5] FIG. 3 is a first view of the four-axis stage of FIG. 2 with the first and third actuators extended along the "X-axis", with a second actuator (not shown) behind the first actuator and a fourth actuator (not shown) behind the third actuator. [Figure 6] A second view of the four-axis stage of FIG. 2 , opposite the first view, with the second and fourth actuators extended along the “Y-axis”, with a first actuator (not shown) behind the second actuator and a third actuator (not shown) behind the fourth actuator. [Figure 7] FIG. 6 is a first view of the four-axis stage of FIGS. 2 and 5 with a second actuator (not shown) behind the first actuator and a fourth actuator (not shown) behind the second actuator, with the first actuator contracted and the third actuator extended to pitch the top plate. [Figure 8] FIG. 7 is a second view of the four-axis stage of FIGS. 2 and 6, with a first actuator (not shown) behind the second actuator and a third actuator (not shown) behind the fourth actuator, with the second actuator extended and the fourth actuator retracted to yaw the top plate. [Figure 9] FIG. 3 is a diagram of the four-axis stage of FIG. 2 with the base plate removed for clarity. [Figure 10] 1 is a single axis / dual actuator movement table applicable to a 4 axis stage in accordance with the principles of the inventive concept; [Figure 11] 1 is a single axis / single actuator movement table applicable to a 5 axis stage in accordance with the principles of the inventive concept. [Figure 12] FIG. 2 illustrates one embodiment of a top view of a 5-axis positioning stage in accordance with the principles of the inventive concepts. [Figure 13] FIG. 13 illustrates another embodiment of a multi-axis positioning stage capable of achieving "rolling" motion of a top plate in accordance with the principles of the inventive concept. [Figure 14A] FIG. 13 is a diagram of another embodiment of a 4-axis stage using manual actuators capable of single digit micron precision in accordance with the principles of the inventive concept. [Figure 14B] FIG. 13 is a diagram of another embodiment of a 4-axis stage using manual actuators capable of single digit micron precision in accordance with the principles of the inventive concept. [Figure 14C] FIG. 13 is a diagram of another embodiment of a 4-axis stage using manual actuators capable of single digit micron precision in accordance with the principles of the inventive concept. [Figure 15] FIG. 1 illustrates one embodiment of a 5-axis positioning stage using cylindrical magnets in the joints, in accordance with the principles of the inventive concept. [Figure 16] FIG. 1 is a block diagram of one embodiment of a photonic positioner including an electronic controller in accordance with the principles of the inventive concept. [Figure 17A] FIG. 1 is a diagram of one embodiment of a photonic positioner system using a four-axis positioning stage in accordance with the principles of the inventive concept. [Figure 17B] FIG. 17B is a diagram of the photonic positioner system of FIG. 17A. [Figure 18] FIG. 13 is a front end view of another embodiment of a multi-axis positioning stage in accordance with an aspect of the present concept. [Figure 19] FIG. 19 is a front end view of the multi-axis positioning stage of FIG. 18 with the first and third actuators extended. [Figure 20]FIG. 19 is a front end view of the multi-axis positioning stage of FIG. 18 with the second and fourth actuators extended. [Figure 21] FIG. 19 is a front end view of the multi-axis positioning stage of FIG. 18 with the first, second, third, and fourth actuators extended. [Figure 22] FIG. 19 is a front end view of the multi-axis positioning stage of FIG. 18 with the top plate tilted. [Diagram 23] FIG. 19 is a perspective view of the multi-axis positioning stage of FIG. 18 with the top plate tilted. [Figure 24] FIG. 19 is a side view of the multi-axis positioning stage of FIG. 18 with the top plate tilted. [Diagram 25] FIG. 13 is a perspective view of another embodiment of a multi-axis positioning stage in accordance with aspects of the present concept. [Figure 26] FIG. 26 is a perspective view of the multi-axis positioning stage of FIG. 25 with the first and third actuators extended. [Figure 27] FIG. 26 is a front end view of the multi-axis positioning stage of FIG. 25 with the first and third actuators extended. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0059] Various aspects of the inventive concepts will be described more fully hereinafter with reference to the accompanying drawings, in which several example embodiments are shown, however, the inventive concepts may be embodied in many different forms and should not be construed as limited to the example embodiments set forth herein.
[0060] Although the present specification may use terms such as first, second, etc. to describe various elements, it should be understood that these elements should not be limited by these terms. These terms are used to distinguish one element from another, but do not imply a required order of the elements. For example, a first element can be called a second element, and similarly, a second element can be called a first element, without departing from the scope of the present invention. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. The term "or" is not used in the sense of an exclusive or, but rather in the sense of an inclusive or.
[0061] When an element is referred to as being "on" or "connected" or "coupled" to another element, it will be understood that the element may be directly on or connected to the other element, or that there may be intervening elements. In contrast, when an element is referred to as being "directly on" or "directly connected to" or "directly coupled" to another element, there are no intervening elements. Other words used to describe relationships between elements should be interpreted in a similar manner (e.g., "between" and "directly between," "adjacent" and "directly adjacent," etc.).
[0062] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms unless the context clearly indicates otherwise. It will be further understood that "comprises", "comprising", "including" and / or "comprising", as used herein, specifies the presence of stated features, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, steps, operations, elements, components and / or groups thereof.
[0063] Spatially relative terms such as "below," "lower," "lower side," "above," and "upper" may be used to describe the relationship of an element and / or feature to other elements and / or features, for example, as shown in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use and / or operation in addition to the orientation shown in the figures. For example, if the device in the figures is turned over, elements described as "below" and / or "below" the other elements or features would then be oriented "above" the other elements or features. The device may be oriented in another way (e.g., rotated 90 degrees or at another orientation) and the spatially relative descriptors used herein may be interpreted accordingly.
[0064] Exemplary embodiments are described herein with reference to cross-section illustrations that are schematic illustrations of idealized exemplary embodiments (and intermediate structures). As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and / or tolerances, are to be expected. Thus, exemplary embodiments should not be construed as limited to the particular shapes of regions illustrated herein but should include deviations in shapes that result, for example, from manufacturing.
[0065] To the extent that functional features, operations, and / or steps are described herein or otherwise understood to be included in various embodiments of the inventive concepts, such functional features, operations, and / or steps may be embodied in functional blocks, units, modules, operations, and / or methods. And, to the extent that such functional blocks, units, modules, operations, and / or methods include computer program code, such computer program code may be stored in a computer-readable medium, such as, for example, a non-transitory memory and medium executable by at least one computer processor.
[0066] In an exemplary embodiment according to the principles of the inventive concepts, a multi-axis positioner or positioning stage includes a support plate supported by a plurality of actuators, such as one or more prism joint actuators. In a preferred embodiment, one or more of the actuators include an actuator joint having five degrees of freedom (DOF) relative to the support plate. In various embodiments, one or more of the actuators include an actuator joint having four DOF relative to the support plate. In operation, as one or more of the actuators extend or retract, the pivot point of a 5DOF actuator can shift in any axis other than the axis of motion of that actuator (i.e., the axis defined by the extension and retraction of the actuator).
[0067] In various embodiments, the support plate can include an upper surface that supports the object and a lower surface that is engaged by the movable ends of at least some of the actuators. One or more actuators can be disposed between the top plate and the one or more structures. In some embodiments, at least some of the actuators can have a first end that is fixed or coupled to a base plate or base structure and a second end that engages and moves with the support (or top) plate.
[0068] In an exemplary embodiment, magnetic forces, gravity, and / or a flexible polymer such as silicone can be used to keep the five DOF pivot points in contact with their respective (i.e., top or bottom) plates when the prism actuator is retracted.
[0069] In some example embodiments, at least two of the prism actuators can be perpendicular to at least two other prism actuators.
[0070] In some embodiments, a fifth axis of movement can be included. If a fifth axis is included, in some embodiments, its associated prism actuator can be positioned perpendicular to the other four prism actuators.
[0071] In an exemplary embodiment, the actuators can be any of several types, such as, for example, piezoelectric actuators, manual micrometer screws, magnetic actuators, stepping motors with linear actuators (either integrated or separate), hydraulic cylinders, pneumatic cylinders, or rotary motors with eccentric cams, for example. In an exemplary embodiment according to the principles of the inventive concept, the positions are set such that the push / pull force exerted by each actuator is greater than the shear friction of all other actuators combined. In an exemplary embodiment, this can be achieved by using a material with high retention but low shear force, such as a hard metal actuator end with a spherical, flat, or pointed surface that is magnetically coupled to and held in contact with a hard flat metal surface of a support plate. In such an embodiment, only one of the contact surfaces (i.e., either the hard metal actuator end surface or the hard flat metal surface) is magnetized. This is because, if both sides are magnetic, they are semi-constrained with a sliding axis and therefore behave like a spherical 3DOF joint.
[0072] In an exemplary embodiment according to the principles of the inventive concept, the positioning stage includes a plurality of prism joint actuators, a base plate (or structure), and a top plate. The top plate is a support plate that can support a device to accurately position the device. The top plate may be supported by a plurality of prism actuators, which are in turn supported by a base plate or other structure. In an exemplary embodiment, one or more actuators are fixed to a portion of the base plate that positions each actuator at an angle relative to a vertical axis or plane. In an exemplary embodiment, the sides of the top plate are formed at the same angle relative to a vertical axis or plane as the sides of the base plate, although other configurations are contemplated within the scope of the inventive concept. For example, the vertical surface can be a surface that extends perpendicularly through the center length of the top plate and the base plate. In various embodiments, for example when the actuators have equal lengths, one or more sides of the top plate can be parallel to one or more sides of the base plate at at least one location of the top plate.
[0073] In various embodiments, a magnetic field can be established between the supporting actuator end and a side of the top plate, thereby forming a magnetic joint between a portion of the top plate surface and the actuator end for at least one actuator. In various embodiments, either the actuator end or the angled side of the top plate includes or is formed of a magnetic field generating material, e.g., a magnet, and the other includes or is made of a magnetic material, e.g., a ferrous metal. In an exemplary embodiment, the actuator end can be in the shape of a hemisphere, although other shapes and combinations, such as a cylinder, are contemplated within the concept of the invention. In various embodiments, the actuator ends include or are formed of a magnetic material, and each magnetic material end is configured to contact a magnet or magnetic surface on a side of the top plate, thereby movably supporting the top plate above the base plate.
[0074] In some embodiments, the magnets on the sides of the top plate conform to the outer surface of the top plate. The inner surface of the top plate need not be magnetic or contain magnets. In some embodiments, the top plate can have a cross section that is flat, V-shaped, semi-cylindrical, or another shape.
[0075] In operation, in a preferred embodiment, the distal end of the actuator is maintained in contact with the magnet on the outer or side surface of the top plate by the force of the magnet. When the actuator is actuated, e.g., extended or retracted, the top plate moves according to a direction of operation determined by the movement of the actuator. Thus, the actuator can be extended and retracted along an axis. The distal end of the actuator that is in contact with the magnet on the opposite side of the top plate remains in contact with the magnet by the magnetic force of the magnet acting on the magnetic material of the distal end of the actuator. At the same time, the distal end of such actuator allows the magnet (and the top plate) to slide in a direction determined by the movement of the actuated actuator. With respect to actuation, this opposite actuator can be passive, i.e., not actuated, or actuated in a different direction and / or to a different extent, in various embodiments.
[0076] A multi-axis positioner or positioning stage according to the principles of the inventive concept may take the form of a parallel positioner. As a parallel positioner, this device does not suffer from the mechanical stacking problems associated with multiple single-axis stages stacked on top of each other in what is sometimes called a kinematic chain. Furthermore, unlike a hexapod, a positioning stage according to the principles of the inventive concept allows any combination of four actuators to extend or contract by any amount at any speed without stage constraint. Each actuator may be arranged to affect the movement of two different axes of the top plate of the stage. To implement a single axis movement, the two actuators may be moved such that they complement each other in the desired axis and cancel each other in the undesired axis. As a result, in an exemplary embodiment according to the principles of the inventive concept, the single axis stage movement may employ dual actuator movement. The single axis stage movement, and the associated actuator movements, are shown in the tables of Figures 10 and 11.
[0077] In addition to being parallel actuators, a positioning stage according to the principles of the present concept can have several other advantages. For example, a positioning stage according to the principles of the present concept can be expanded in stages from 4 to 6 axes, whereas a Stewart platform always has 3 or 6 axes. Unlike a kinematic chain, a positioning stage according to the principles of the present concept does not exhibit tolerance stack-up of the individual stages. A positioning stage according to the principles of the present concept does not require rotary or linear bearings, whereas a kinematic chain requires one for each free axis. With a positioning stage according to the principles of the present concept, each axis of motion requires only two actuators that move at a fixed, intuitive ratio, and therefore it is relatively easy to achieve the desired motion. As shown before, this is not the case with the Stewart platform. Furthermore, unlike the Stewart platform, there is no need to control the actuation speed to prevent binding of the stage, and individual actuators can be moved without binding the stage. In an exemplary embodiment, the top plate of the positioning stage can be easily removed and replaced by simply separating the interfaces, such as the magnetic interface, between the actuators and the top plate.
[0078] In an exemplary embodiment, the resolution and stiffness of the positioning stage may depend on the quality of the actuator, the smoothness of the slider components, whether hemispherical, cylindrical, or otherwise, and the strength of the magnetic (or other) forces holding together the joints formed between the actuator and the top plate. All these aspects can be optimized to create sub-micron precision positioning stages at a fraction of the cost of similar precision hexapods. In many cases, positioning stages according to the principles of the inventive concept will outperform standard kinematic chains while at the same time being more cost-effective. In an exemplary embodiment, the holding force (e.g., magnetic holding force) of the actuator slider (or the other four of the five DOF connections) is greater than the coefficient of friction of all other actuator joints. If this is the case, the top plate will settle into an equilibrium state that allows the four (or more) connections to slide or rotate as needed such that all contact points are maintained.
[0079] A 4-axis positioning stage with a constrained Z-axis where other degrees of freedom are not interfered with may be implemented in accordance with the principles of the inventive concept by constraining or limiting such Z-axis motion using a rigid beam, or by replacing one of the four 5DOF actuator joints with a 4DOF joint that limits the Z-axis motion as shown in FIG. 15.
[0080] 2-9 combine to provide an illustration of an exemplary embodiment of a four-axis positioning stage in accordance with the principles of the inventive concept.
[0081] Figure 2 shows a front end view of an embodiment of a multi-axis positioning stage or positioner with all actuators retracted, a third actuator (not shown) behind the first actuator, and a fourth actuator (not shown) behind the second actuator. Figures 5-9 show the third and fourth actuators. For example, as can be seen in Figure 9, the third actuator is behind the first actuator and the fourth actuator is behind the second actuator.
[0082] With reference to Figure 2, in this view all actuators are retracted. In this exemplary embodiment, the positioning stage is a four-axis positioning stage 100 including a base plate 102, a top plate 104, and a number of actuators, which may be prism actuators. The number of actuators includes a first actuator 106 (i.e., prism actuator 1), a second actuator 108 (i.e., prism actuator 2), a third actuator 110 (i.e., prism actuator 3), and a fourth actuator 112 (i.e., prism actuator 4).
[0083] In the exemplary embodiment, the base plate 102 includes angled side pieces 118, 120. In this embodiment, θ 1 and θ 2 and represent the angle of the inner surface of the side pieces 118 and 120 with respect to the vertical axis and / or the vertical plane, respectively. The inclined side pieces of the base plate may also be formed at an angle θ with respect to the horizontal plane, where in this embodiment θ=θ 1 =θ 2 In other embodiments, θ≠θ 1 , θ ≠ θ 2 and / or θ 1 ≠θ 2 In other embodiments, θ may be irrelevant, and θ 1 =θ 2 can still hold. In this embodiment, the outer surfaces 122, 124 of the top plate 104 are at the same angle θ 1 , θ 2 Thus, the inner surface of the side piece 118 of the base plate 102 can be parallel to the outer surface 122 of the top plate 104, and the inner surface of the side piece 120 of the base plate 102 can be parallel to the outer surface 124 of the top plate. The vertical plane can be a plane that passes through the center of the top plate 104 and the base plate 102 and extends vertically.
[0084] In the embodiment of Figure 2, the base plate 102 includes a middle portion from which the side plates 118 and 120 extend. The middle portion can be a planar piece that lies in a horizontal plane, although the middle portion need not be planar in all embodiments. Also, while the side pieces 118, 120 are shown as being connected or part of the same structure, this need not be the case in all embodiments. In other embodiments, the side pieces 118, 120 may be part of different structures or may be separate plates attached to one or more other structures.
[0085] In this embodiment, each of the actuators 106, 108, 110, and 112 extends from one of the side pieces 118, 120 of the base plate 102 in a direction toward the top plate 104. For example, in this embodiment, each actuator is fixed or coupled to a side piece of the base plate 102 and extends toward a corresponding side 122 or 124 of the top plate 104 at a 90 degree angle relative to the corresponding side piece 118 or 120.
[0086] The distal end of each actuator 106, 108, 110, and 112 includes a magnetic material. In this embodiment, each of the actuators 106, 108, 110, and 112 includes a ferrous metal hemispherical end 134, 136, 138, and 140. Magnets 126, 128, 130, and 132 are disposed on or within the sides 122, 124 of the top plate 104 at locations corresponding to the ferrous metal hemispherical ends 134, 136, 138, and 140 of the respective actuators 106, 108, 110, and 112.
[0087] FIG. 3 shows the same front end view of the four-axis positioning stage of FIG. 2, but in this case the first and third actuators are extended along an axis (the "X-axis"). In FIG. 3 the first actuator 106 and the third actuator 110 are extended to move the top plate 104 in the direction of the X-axis, as indicated by the "X-axis arrows". As already indicated, the third actuator 110 (actuator 3) is behind the first actuator 106 (actuator 1) and the fourth actuator 112 (actuator 4) is behind the second actuator 108 (actuator 2). In the exemplary embodiment, actuator 1 106 and actuator 3 110 are extended by the same amount to provide pure X-axis movement. The dashed lines indicate the original position of the top plate 104 and magnets 126, 128, which is the position of the top plate in FIG. 2.
[0088] FIG. 4 shows the same end view of the four-axis positioning stage of FIG. 2, but in this case the second and fourth actuators are extended along an axis (the "Y-axis"). In the exemplary embodiment of FIG. 4, actuators 1 106 and 3 110 (X-axis) and actuators 2 108 and 4 112 (Y-axis) are extended. As already shown, the third actuator 110 is behind the first actuator 106, and the fourth actuator 112 is behind the second actuator 108. In the exemplary embodiment, the first actuator 106 and the third actuator 110 are extended by the same amount to effect X-axis movement. The second actuator 108 and the fourth actuator 112 are extended by the same amount to effect Y-axis movement. The dashed lines indicate the original positions of the top plate 104 and magnets 126, 128.
[0089] FIG. 5 shows a view of the first and third actuators of the four-axis positioning stage of FIG. 2 extended along the "X-axis", with a second actuator (not shown) behind the first actuator and a fourth actuator (not shown) behind the third actuator. In the exemplary embodiment of FIG. 5, the first actuator 106 and the third actuator 110 are extended by the same amount to effect movement only in the direction of the X-axis. From this perspective, the second actuator 108 is behind the first actuator 106 and the fourth actuator 112 is behind the third actuator 110. The dashed lines indicate the original positions of the top plate 104 and magnets 126, 130.
[0090] FIG. 6 shows a view of the second and fourth actuators of the four-axis positioning stage of FIG. 2 extended along the "Y-axis", with the first actuator (not shown) behind the second actuator and the third actuator (not shown) behind the fourth actuator. In the embodiment of FIG. 6, the second actuator 108 and the fourth actuator 112 are extended by the same amount to provide movement only in the direction of the Y-axis. From this perspective, the first actuator 106 is behind the second actuator 108 and the third actuator 110 is behind the fourth actuator 112. The dashed lines indicate the original positions of the top plate 104 and magnets 128, 132.
[0091] FIG. 7 illustrates a diagram in which the first actuator 106 is contracted and the third actuator 110 is extended to pitch the top plate 104, with the second actuator 108 (not shown) behind the first actuator and the fourth actuator 112 (not shown) behind the second actuator.
[0092] FIG. 8 shows a diagram of a four-axis positioning stage with the second actuator 108 extended and the fourth actuator 112 retracted to yaw the top plate 104, with the first actuator 106 (not shown) behind the second actuator and the third actuator 110 (not shown) behind the fourth actuator.
[0093] Figure 9 shows a view of the four-axis positioning stage of Figure 2 with the base plate 102 omitted for clarity. In the exemplary embodiment of Figure 9, this view of the four-axis positioning stage shows the relative positions of the first, second, third and fourth actuators 106, 108, 110 and 112 along with their respective associated magnets 126, 128, 130 and 132 and top plate 104.
[0094] FIG. 10 illustrates a single axis / dual actuator movement table that can be applied to a four axis positioning stage according to the principles of the inventive concept. The table in FIG. 10 illustrates a combination of dual actuator movements that achieve top plate movement according to the principles of the inventive concept. For example, to extend the top plate in only the positive X axis direction, the first actuator 106 and the third actuator 110 are extended while the second actuator 108 and the fourth actuator 112 remain in place, and to extend the top plate in only the positive Y axis direction, the second actuator 108 and the fourth actuator 112 are extended while the first actuator 106 and the third actuator 110 remain in place.
[0095] Figure 11 shows a single axis / single actuator movement table that can be applied to a 5-axis positioning stage according to the principles of the inventive concept. For example, Figure 12 shows a fifth actuator 113 added to affect the movement of the top plate 4 in the Z axis, which is in the horizontal plane. In other embodiments, a sixth actuator can be provided opposite the fifth actuator.
[0096] The table of Figure 11 shows, as an example, the single axis, single actuator movement of a fifth actuator 113 when added to actuators 106, 108, 110, and 112. That is, the table of Figure 11 can be added to the table of Figure 10 if five actuators are used. Thus, a five-axis positioning stage as shown in Figure 12 can be provided with positive Z axis movement provided by extension of the fifth actuator 113 and negative Z axis movement provided by contraction of the fifth actuator 113. In an exemplary embodiment in which a four-axis positioning stage is used, the fifth actuator 113 may be replaced by, for example, a rigid beam, with the Z axis being constrained.
[0097] FIG. 13 illustrates another embodiment of a multi-axis positioning stage capable of achieving "rolling" motion of the top plate in accordance with the principles of the inventive concept. In an exemplary embodiment in accordance with the principles of the inventive concept, a sixth rolling axis of motion can be introduced as shown in FIG. 13. In this exemplary embodiment, the top plate 104 is semi-cylindrical, as is the magnet 133. In such an exemplary embodiment, motion in the sixth axis does not interfere with motion in the other five axes. Rolling can be achieved by selective extension and / or contraction of the actuators 106, 108, 110, and 112. A fifth actuator 113 is again optional and can be provided if Z-axis motion is intended.
[0098] 14A, 14B, and 14C provide end, perspective, and exploded views, respectively, of an exemplary positioner according to the principles of the inventive concept. In this exemplary embodiment, the top plate 104 and the base plate 102 are V-shaped, where the sides have the same angle θ with respect to the vertical axis, where in this embodiment θ=θ 1 =θ 2 In another embodiment, θ 1 ≠θ 2In this exemplary embodiment, the first to fourth actuators 106, 108, 110, and 112 penetrate the base plate 102 and contact the magnets 135, 137 positioned on the side of the top plate 104.
[0099] Magnets 135 and 137 are disposed on or in the sides 122 , 124 of the top plate 104 at locations corresponding to the ferrous metal hemispherical ends 134 , 136 , 138 , and 140 at the distal ends of the respective actuators 106 , 108 , 110 , and 112 .
[0100] In an exemplary embodiment, the actuators 106, 108, 110, and 112 may be precision adjustment mechanisms, such as micrometer screws 106a, 108a, 110a, 112a, that allow single digit micron precision adjustment.
[0101] 15 is a diagram of one embodiment of a 5-axis positioning stage using a cylindrical magnet in the joint in accordance with the principles of the inventive concept. As shown in the exemplary embodiment of FIG. 15, in this exemplary embodiment, one of the magnets 139 attached to the top plate 104 may be in the form of a cylindrical magnet providing a 4DOF joint resulting in a positioner with limited motion in the Z axis, for example. The cylindrical magnet may be configured, for example, by bending to provide a sixth axis of rolling.
[0102] FIG. 16 is a block diagram of an embodiment of a photonic positioner including an electronic controller according to the principles of the inventive concept. The block diagram of FIG. 16 shows a photonic system 200 using a photonic device 101, such as a fiber splicer or a component thereof, such as an alignment device, in conjunction with a positioner 100 according to the principles of the inventive concept. In an exemplary embodiment, the positioner 100 is controlled by a controller 103, which operates an actuator of the positioner in the manner described above to precisely move the photonic device 101. Such movement may allow, for example, alignment of optical fiber ends. The controller 103 may, for example, receive feedback from the photonic device 101 that the controller uses to adjust the positioner 100. In an exemplary embodiment in which the photonic device 101 is a splicer, for example, a sensor may provide an indication to the controller 103 indicative of the quality of alignment between the fibers, and the controller 103 may use such indication to adjust the positioner for precise alignment of the optical fibers, for example.
[0103] 17A and 17B are side views of a photonic positioner system 105 using a positioner according to the principles of the inventive concept. In this exemplary embodiment, a pair of positioners 100 each support optical fiber ends F1, F2 for splicing. Each of the positioners 100 can be operated, for example using an electronic controller 103, as described above, to align the ends of the fibers F1, F2 for splicing by an optical fiber splicer that includes a heating element, such as a plasma heater (not shown), configured to heat the fiber ends once aligned using the positioner 100. In an exemplary embodiment, the top plate of the positioner 100 can include or support a fiber holder 107. Such fiber holders are known and can include grooves in two flat upper surfaces to hold one or more fibers in place for positioning and splicing.
[0104] With reference to Figures 18-27, alternative embodiments of a multi-axis positioner or positioning stage according to aspects of the inventive concept are described. Unless otherwise stated, the above description applies equally to these embodiments or aspects thereof. As noted above, a multi-axis positioner, also referred to herein as a parallel positioner or positioning stage, can employ multiple actuators forming multiple joints with a support plate. In these embodiments, the multiple joints include at least two four-degree-of-freedom (4DOF) joints in combination with two other joints, where each of the other joints can be a 4DOF joint or a 5DOF joint. In various embodiments, the positioner includes either two 4DOF joints and two 5DOF joints, one 4DOF joint and one 5DOF joint, or two 4DOF joints. Thus, the interface between the positioning end of the actuator and the support plate is a 4DOF joint or a 5DOF joint. Other embodiments can include different combinations of 4DOF and / or 5DOF joints with the support plate. The support plate may be configured to support one or more objects which are preferably to be positioned with high precision.
[0105] In various embodiments, the system includes three or more actuators that maintain contact with the structure through joints having four or five degrees of freedom (DOF). Optionally, the system can also include no actuators that maintain contact with the structure through joints having three or fewer DOF.
[0106] In an exemplary embodiment, the positioner may also include at least one bottom plate (or structure), and the actuator may be disposed between the at least one bottom plate and the top plate and secured to the at least one bottom plate (or structure).
[0107] In operation, when one or more of the actuators extends or contracts, the pivot point of the interface of the remaining actuator with the support plate (e.g., 4DOF and / or 5DOF joint) can shift in any of at least four axes other than the axis of motion of that actuator. As already indicated, the 4DOF joint with the support plate can be formed by an actuator having an end with an edge slider or a cylindrical slider, as an example. In a preferred embodiment, similar to the 5DOF joint embodiment described above, at least two of the prism actuators can be perpendicular to at least two other prism actuators, and if a fifth or sixth axis is added, their associated prism actuators can be arranged perpendicular to the other four prism actuators in various embodiments.
[0108] As with the 5DOF embodiment described above, the ends of the actuators can be magnetically coupled to a support (or top) plate. In operation, as one or more of the actuators extends or contracts, the pivot points of the remaining actuators can shift and move relative to the support (or top) plate while remaining magnetically movably coupled to the top plate.
[0109] As mentioned above, in an exemplary embodiment, the actuators may be any of several types, such as piezoelectric actuators, manual micrometer screws, magnetic actuators, stepper motors with linear actuators (either integrated or separate), hydraulic cylinders, pneumatic cylinders, or rotary motors with eccentric cams, for example. In an exemplary embodiment according to the principles of the inventive concept, the positioner is configured such that the push / pull force exerted by each actuator is greater than the shear friction of all the other actuators combined. In an exemplary embodiment, this can be accomplished by using a material with high holding strength but relatively low shear strength, for example, hard metal end faces of the actuators that are held in magnetic contact with a hard, flat metal surface of a top plate.
[0110] 18-27 provide illustrations of an exemplary embodiment of a multi-axis positioner or positioning stage that uses at least two actuators with cylindrical slider ends to form a 4DOF joint with a support plate in accordance with the principles of the inventive concept. The positioner can include two or more actuators that engage a support plate with a 4 or 5DOF joint.
[0111] The support plate can be configured to hold an object to be positioned. In some embodiments, the object can be at least one optical fiber. In some embodiments, the support plate can include a groove or channel configured to maintain the object in a preferred position. In some embodiments, the support plate can include a V-shaped groove configured to maintain the object in a preferred position. In some embodiments, the positioner or positioning stage can form part of a fiber processing machine, such as, by way of example, an optical fiber splicer, and the groove can be configured to hold or support at least one optical fiber.
[0112] 18 shows a front end view of an embodiment of a multi-axis positioning stage or positioner 300 having at least four actuators 306, 308, 310, 312 supporting a support (or top) plate 304. A first actuator 306 and a second actuator 308 are visible in this view, with a third actuator 310 (not shown) behind the first actuator 306 and a fourth actuator 312 (not shown) behind the second actuator 308.
[0113] With reference to Figure 18, in this view all of the actuators are retracted. In this exemplary embodiment, the positioning stage 300 includes a base plate 302, a top plate 304, and a number of actuators 306, 308, 310, 312, one or more of which may be prism actuators. In various embodiments, the positioning stage 300 or its base plate may optionally include an end plate 317, as described with respect to Figures 23 and 24.
[0114] In the exemplary embodiment, similar to the previously described embodiment, the base plate 302 includes side pieces 318, 320 each having an internal angled side formed at an angle relative to a vertical axis or plane "A." This is discussed, for example, in the θ angle described above as being applicable to this embodiment. 1 and θ 2 For example, the vertical plane A may be a plane that extends vertically through the centers of the top plate 304 and the base plate 302. In other embodiments, θ 1 ≠θ 2 18. The sides 322, 324 of the top plate 304 are formed at the same angle relative to the vertical axis or plane A. Thus, the side piece 318 of the base plate 302 is parallel to the side 322 of the top plate 304, and the side piece 320 of the base plate is parallel to the side 324 of the top plate 304. In the embodiment of FIG. 18, the base plate 302 includes a middle portion from which the side pieces 318 and 320 extend. Although the middle portion can be a substantially planar piece that lies in a horizontal plane, the middle portion need not be planar or flat in all embodiments, and may include a recess as shown in FIG. 18, for example.
[0115] In this embodiment, each of the actuators 306, 308, 310, and 312 extends from one of the side pieces 318, 320 of the base plate 302 in a direction toward the top plate 304. For example, in this embodiment, each actuator is fixed or coupled to a side piece of the base plate 302 and is oriented at a 90 degree angle relative to a corresponding actuator on the opposite side piece 318 or 320.
[0116] The distal end of each actuator 306, 308, 310, and 312 may include a magnetic material. In the embodiment of Figures 18-24, each of actuators 306, 308, 310, and 312 includes a ferrous metal cylindrical end 334, 336, 338, and 340, although other linear ends may be used in other embodiments. Magnets such as magnets 126, 128, 130, and 132 described above may be disposed on or in sides 322, 324 of top plate 304 at locations corresponding to ferrous metal cylindrical ends 334, 336, 338, and 340 of respective actuators 306, 308, 310, and 312.
[0117] FIG. 19 shows the same front end view of the positioning stage 300 of FIG. 18, but in this case the first actuator 306 and the third actuator (behind the first actuator) are extended along an axis (the "X-axis"). The second actuator 308 and the fourth actuator (behind the second actuator) remain retracted (or are not extended). In FIG. 19 the first actuator 306 and the third actuator 310 are extended to move the top plate 304 in the direction of the X-axis, as indicated by the X-axis arrow (see FIG. 3). In an exemplary embodiment, the first actuator 306 and the third actuator 310 are extended by the same amount to effect purely X-axis movement.
[0118] FIG. 20 shows the same front end view of the positioning stage 300 of FIG. 18, but in this case the second actuator 308 and the fourth actuator (behind the second actuator) are extended along an axis (the "Y-axis"). The first actuator 306 and the third actuator (behind the first actuator) remain retracted (or are not extended). In FIG. 20, the second actuator 308 and the fourth actuator 312 are extended to move the top plate 304 in the direction of the Y-axis, as indicated by the Y-axis arrow (see FIG. 4). In an exemplary embodiment, the second actuator 308 and the fourth actuator 312 are extended by the same amount to effect purely Y-axis movement.
[0119] Figure 21 shows the same front end view with all actuators extended the same amount to effect movement in the Z direction. In Figure 21, actuators 306 and 310 (X-axis) and actuators 308 and 312 (Y-axis) are extended. As previously shown, the third actuator 310 is behind the first actuator 306 and the fourth actuator 312 is behind the second actuator 308. In an exemplary embodiment, the first actuator 306 and the third actuator 310 are extended the same amount to effect movement in the X-axis, and the second actuator 308 and the fourth actuator 312 are extended the same amount to effect movement in the Y-axis.
[0120] FIG. 22 shows a left perspective view of the positioning stage 300 of FIG. 18 where the first actuator 306 is extended a greater distance than the third actuator 310, and the second actuator 308 is similarly extended a greater distance than the fourth actuator 312, resulting in the top plate 304 tilting upward.
[0121] Similarly, the third actuator 310 can be extended a greater distance than the first actuator 306, and the fourth actuator 312 can be extended a greater distance than the second actuator 308, resulting in the top plate 304 tilting downward.
[0122] 23 shows a side perspective view in which the first actuator 306 is extended further than the third actuator 310 and the fourth actuator 312 is extended further than the second actuator 308, resulting in both an upward tilt and partial rotation of the top plate 304. In FIG. 23, the end plate 317 is partially visible. The end plate can be fixed to or part of the base plate 302 as shown. In other embodiments, the end plate 317 need not contact or be part of the base plate. That is, in various embodiments, the end plate 317 is detached and / or separate from the base plate 302.
[0123] FIG. 24 shows a side view of the positioning stage 300 with the base plate omitted but the top plate 304 shown. Of the four actuators 306, 308, 310, and 312, only the first and third actuators 306, 310 are visible from this view. A cylindrical end 334 of the first actuator and a cylindrical end 338 of the third actuator 310 are in direct contact with the top (or support) plate 304 for direct positioning. The end plate 317 includes a magnetic ball 319 for engaging one end of the top plate 304. As with the joints discussed above, in various embodiments, the magnetic ball 319 can be positioned to engage a magnet (not shown) located on or in the top plate 304.
[0124] Although the embodiment of Figures 18-24 is shown with four actuators having sliding cylindrical ends forming a 4DOF joint with the top plate, as noted above, combinations of 4DOF and 5DOF actuators are contemplated within the concept of the present invention, as shown in the exemplary embodiment of Figures 25-27 having a combination of actuators with cylindrical ends and ball ends, as previously described.
[0125] 25 illustrates a multi-axis positioning stage or positioner 400. The positioning stage 400 includes two 4DOF actuators 310, 312 and two 5DOF actuators 406, 408, as well as a base plate 302, a top plate 304, and an end plate 317 with a magnetic ball 319.
[0126] While any combination of actuator extension and contraction can be achieved, in this example, the first and second actuators 406, 408 are extended a greater distance than the third and fourth actuators 310, 312, resulting in an upward tilt at the front of the top plate 304.
[0127] FIG. 26 is a perspective view of the positioning stage 400 with the first actuator 406 and the third actuator 410 extended by the same amount, resulting in the top plate 404 moving in the X-axis direction. FIG. 26 is a front view of the positioning stage 400 of FIG. 25 with the same actuator extension arrangement. FIG. 27 shows a front end view of the same actuator configuration, by way of example. As will be appreciated by those of ordinary skill in the art having the benefit of this disclosure, other combinations of actuator extension and contraction can be achieved within the scope of the inventive concept. In this embodiment, each actuator includes electromechanical components forming part of the actuator that can be controlled by at least one controller, such as the controller 103, that effect the extension and contraction of the actuator. Such a controller can include at least one processor that executes computer instructions to drive the actuators.
[0128] While the above describes what is believed to be the best mode and / or other preferred embodiments, it is understood that various modifications may be made thereto and that the invention or inventions may be embodied in various forms and embodiments, which are applicable to numerous applications, only a few of which are described herein. It is intended that the following claims claim what is literally described and all equivalents thereof, including all modifications and variations that are within the scope of each claim.
[0129] It will be appreciated that certain features of the invention that are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention that are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination.
[0130] For example, it is to be understood that all features (whether independent or dependent) recited in any of the claims can be combined in any given manner.
Claims
1. a structure (304) having a groove or channel configured to maintain the object in a preferred position; At least one base (302); a plurality of actuators (306, 308, 310, 312) configured to support the structure over the at least one base and move the structure relative to the at least one base in response to expansion or contraction of one or more actuators, the plurality of actuators (306, 308, 310, 312) configured to tilt and rotate the structure; Equipped with The three or more actuators include ends with sliders that maintain contact with the structure via joints having at least four degrees of freedom (DOF).
2. 2. The positioner of claim 1, wherein the three or more actuators include at least two actuators that maintain contact with the structure via a joint having five DOF.
3. 3. The positioner of claim 2, wherein the three or more actuators include at least two actuators that maintain contact with the structure via a joint having four DOF.
4. 2. The positioner of claim 1, wherein the three or more actuators include at least two actuators that maintain contact with the structure via a joint having four DOF.
5. 2. The positioner of claim 1, wherein at least one joint having 4 DOF is a magnetic joint.
6. 2. The positioner of claim 1, wherein at least one joint having 5 DOF is a magnetic joint.
7. 2. The positioner of claim 1, wherein each of sliders provided at the ends of the three or more actuators has a magnetic joint with the structure.
8. 2. The positioner of claim 1, wherein an actuator having a 4DOF joint with the structure has a cylindrical end that contacts the structure.
9. 2. The positioner of claim 1, wherein an actuator having a 5DOF joint with the structure has a hemispherical end that contacts the structure.
10. 2. The positioner of claim 1, wherein the structure comprises a longitudinally extending groove, recess, or channel.
11. 11. The positioner of claim 10, wherein the longitudinally extending groove, recess or channel is configured to hold at least one optical fiber.
12. 11. The positioner of claim 10, wherein the structure includes a V-groove configured to hold at least one optical fiber.
13. 2. The positioner of claim 1, the structure comprises a top plate and the at least one base comprises at least one base plate; A positioner, comprising: three or more actuators supporting the top plate coupled to the at least one base plate.
14. 14. The positioner of claim 13, wherein the top plate includes angled sides engaged by the three or more actuators and the at least one base plate includes angled side pieces to which the three or more actuators are coupled, the angled sides of the top plate and the angled side pieces of the at least one base plate forming the same angle with respect to a vertical plane or axis.
15. 15. The positioner of claim 14, wherein the at least one base includes an end plate (317) including a coupling (319) for an end of the top plate (304).
16. 16. The positioner of claim 15, wherein the coupling is a magnetic coupling.
17. 10. A positioner as claimed in claim 1 or any other claim, wherein the three or more actuators include at least two actuators that maintain contact with the structure via a joint having five DOF.
18. 18. A positioner as claimed in claim 17 or any other claim, wherein the three or more actuators include at least two actuators that maintain contact with the structure via a joint having four DOF.
19. 10. A positioner as claimed in claim 1 or any other claim, wherein the three or more actuators include at least two actuators that maintain contact with the structure via a joint having four DOF.
20. 10. A positioner according to claim 1 or any other claim, characterized in that at least one joint having 4 DOF is a magnetic joint.
21. 10. A positioner according to claim 1 or any other claim, characterized in that at least one joint having 5 DOF is a magnetic joint.
22. 2. A positioner as claimed in claim 1 or any other claim, wherein each of the three or more actuators has a magnetic joint with the structure.
23. 10. A positioner as claimed in claim 1 or any other claim, wherein an actuator having a 4DOF joint with the structure has a cylindrical end in contact with the structure.
24. 10. A positioner as claimed in claim 1 or any other claim, wherein an actuator having a 5DOF joint with the structure has a hemispherical end in contact with the structure.
25. 2. A positioner as claimed in claim 1 or any other claim, wherein the structure comprises a longitudinally extending groove, recess or channel.
26. 26. A positioner as claimed in claim 25 or any other claim, wherein the longitudinally extending groove, recess or channel is configured to hold at least one optical fibre.
27. 26. A positioner as claimed in claim 25 or any other claim, wherein the structure includes a V-groove configured to hold at least one optical fibre.
28. 10. A positioner according to claim 1 or any other claim, comprising: the structure comprises a top plate and the at least one base comprises at least one base plate; A positioner, comprising: three or more actuators supporting the top plate coupled to the at least one base plate.
29. 29. A positioner as claimed in claim 28 or any other claim, wherein the top plate includes angled sides engaged by the three or more actuators and the at least one base plate includes angled side pieces to which the three or more actuators are coupled, the angled sides of the top plate and the angled side pieces of the at least one base plate forming the same angle with respect to a vertical plane or axis.
30. 2. A positioner as claimed in claim 1 or any other claim, further comprising an end plate including a coupling for an end of the structure.
31. 31. A positioner as claimed in claim 30 or any other claim, wherein the coupling is a magnetic coupling.
32. a top plate (304) having grooves or channels configured to maintain the object in a preferred position; A base plate (302); three or more actuators (306, 308, 310, 312) configured to support the top plate over the base plate and move the top plate in response to extension or contraction of one or more actuators, each of the actuators including an end with a slider that maintains contact with the top plate via a joint having at least four degrees of freedom (DOF), the actuators configured to tilt and rotate the top plate; A positioner (300) comprising:
33. 33. The positioner of claim 32, wherein the three or more actuators include at least two actuators that maintain contact with the top plate through a joint having four DOF and at least one actuator that maintains contact with the top plate through a joint having five DOF.
34. 33. The positioner of claim 32, wherein the top plate includes angled sides engaged by the three or more actuators and the base plate includes angled side pieces to which the three or more actuators are coupled, the angled sides of the top plate and the angled side pieces of the base plate forming the same angle with respect to a vertical plane or axis.
35. 33. The positioner of claim 32, wherein the actuator having a 4DOF joint with the top plate has a cylindrical end.
36. 33. A positioner as claimed in claim 32 or any other claim, wherein the three or more actuators include at least two actuators that maintain contact with the top plate through a joint having four DOF and at least one actuator that maintains contact with the top plate through a joint having five DOF.
37. 33. A positioner as claimed in claim 32 or any other claim, wherein the top plate includes angled sides engaged by the three or more actuators and the base plate includes angled side pieces to which the three or more actuators are coupled, the angled sides of the top plate and the angled side pieces of the base plate forming the same angle with respect to a vertical plane or axis.
38. 33. A positioner as claimed in claim 32 or any other claim, wherein the actuator having a 4DOF joint with the top plate has a cylindrical end.
Citation Information
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