A driven foot and its control system, motion platform, POB light machine

Abstract

The application belongs to the technical field of driving equipment, and particularly relates to a driving foot for a chip processing device, a control system thereof, a motion platform and a POB light machine, which comprises: a first driving part and a second driving part arranged oppositely; a first driven part and a second driven part arranged oppositely; a micro-drive piezoelectric motor, which drives the first driving part and the second driving part to open and close symmetrically about a reference plane between the first driving part and the second driving part; a transmission part is arranged between the first driving part, the second driving part and the first driven part and the second driven part respectively; a first mounting seat is arranged at one end of the first driven part, and a second mounting seat is arranged at a far end of the second driven part. The symmetrical transmission structure provided by the application fundamentally eliminates the deflection error caused by asymmetric stress, and ensures the motion accuracy of hundreds of nanometers. Meanwhile, the micro-drive piezoelectric motor is used as a driving element, and the output displacement of the driving foot is greatly improved on the premise that the required accuracy is still achieved at the output end.

Description

Technical Field

[0001] This invention belongs to the field of drive equipment technology, specifically relating to a drive foot and its control system, motion platform, and POB optical engine for chip processing equipment. Background Technology

[0002] The Projection Object Box (POB), a key mechanical and optical component in an optical lithography system located between the mask and the projection lens, primarily functions to precisely position, level, and protect the mask pattern, as well as control the path of the illumination beam. Some POBs employ a dual-mirror reflection system, with one mirror mounted on a six-degree-of-freedom platform (such as the Stewart platform). This platform requires a motion stroke on the order of hundreds of micrometers, with motion accuracy controlled at the order of hundreds of nanometers. To meet such high motion accuracy, the drive foot typically incorporates a motion reduction mechanism between the drive element and the power output. However, existing drive feet often employ asymmetric lever-type motion reduction mechanisms, leading to two problems: first, asymmetric forces can cause the drive foot to wobble, introducing additional errors; second, the insufficient motion accuracy of the drive element itself forces the motion reduction mechanism to use a large reduction ratio to ensure output accuracy, thus severely limiting the motion stroke of the six-degree-of-freedom platform. Summary of the Invention

[0003] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a drive foot and its control system, motion platform, and POB optical engine that can improve motion stroke while ensuring motion accuracy.

[0004] To achieve the above and other related objectives, the present invention provides a driving foot, comprising: A first active unit and a second active unit are arranged opposite to each other along a first direction; A first driven part and a second driven part are disposed opposite to each other along a second direction, the second direction being perpendicular to the first direction; A micro-piezoelectric motor is disposed between the first active part and the second active part. The micro-piezoelectric motor is configured to drive the first active part and the second active part to open and close symmetrically about a reference plane between them. The reference plane is perpendicular to the first direction. A transmission unit is provided between the first active part, the second active part and the first driven part, the second driven part, and the transmission unit is configured to convert the opening / closing action between the first active part and the second active part along the first direction into the opening / closing action between the first driven part and the second driven part along the second direction. In the second direction, the first driven part is provided with a first mounting seat for connecting an external fixing member at one end away from the second driven part, and the second driven part is provided with a second mounting seat for connecting an external movable member at one end away from the first driven part.

[0005] In an optional embodiment of the present invention, a first hinge mechanism is provided between the first driven part and the first mounting base, which enables the first driven part to swing about at least a first axis and a second axis relative to the first mounting base, wherein the first axis is perpendicular to the second axis, and the first axis and the second axis are perpendicular to the second direction; A second hinge mechanism is provided between the second driven part and the second mounting base, which enables the second driven part to swing about at least a third axis and a fourth axis relative to the second mounting base. The third axis is perpendicular to the fourth axis, and the third axis and the fourth axis are perpendicular to the second direction.

[0006] In an optional embodiment of the present invention, the first axis is parallel to the first direction, and the second axis is perpendicular to the first direction; The third axis is parallel to the first direction, and the fourth axis is perpendicular to the first direction.

[0007] In an optional embodiment of the present invention, the first hinge mechanism includes: a rigid first transition portion, a plate-shaped first flexible hinge disposed between the first driven portion and the first transition portion, and a plate-shaped second flexible hinge disposed between the first transition portion and the first mounting base; in response to the non-deformation state of the first flexible hinge and the second flexible hinge, the plate surface of the first flexible hinge is perpendicular to the first axis, and the plate surface of the second flexible hinge is perpendicular to the second axis. The second hinge mechanism includes: a rigid second transition portion, a plate-shaped third flexible hinge disposed between the second driven portion and the second transition portion, and a plate-shaped fourth flexible hinge disposed between the second transition portion and the second mounting base; in response to the non-deformation state of the third flexible hinge and the fourth flexible hinge, the plate surface of the third flexible hinge is perpendicular to the third axis, and the plate surface of the fourth flexible hinge is perpendicular to the fourth axis.

[0008] In an optional embodiment of the present invention, in the second direction, the first flexible hinge is distributed in a first length interval, the second flexible hinge is distributed in a second length interval, and the first length interval and the second length interval at least partially overlap. In the second direction, the third flexible hinge is distributed in a third length interval, and the fourth flexible hinge is distributed in a fourth length interval, wherein the third length interval and the fourth length interval at least partially overlap.

[0009] In an optional embodiment of the present invention, it further includes: A first limiting portion is used to limit the swing stroke of the first driven portion relative to the first mounting base; and The second limiting part is used to limit the swing stroke of the second driven part relative to the second mounting base.

[0010] In an optional embodiment of the present invention, the transmission unit includes: The first swing arm is hinged to the first active part via a fifth flexible hinge, and the first swing arm is hinged to the first driven part via a sixth flexible hinge. The second swing arm is hinged to the first active part via a seventh flexible hinge, and the second swing arm is hinged to the second driven part via an eighth flexible hinge. The third swing arm is hinged to the second driving part via a ninth flexible hinge, and the third swing arm is hinged to the first driven part via a tenth flexible hinge. The fourth swing arm is hinged to the second driving part via the eleventh flexible hinge, and to the second driven part via the twelfth flexible hinge.

[0011] In an optional embodiment of the present invention, the fifth, sixth, seventh, eighth, ninth, tenth, eleventh, and twelfth flexible hinges are plate-like structures. In response to the non-deformation state of the fifth, sixth, seventh, eighth, ninth, tenth, eleventh, and twelfth flexible hinges, their plate surfaces are parallel to a third direction, which is perpendicular to the first and second directions. The combined structure formed by the first swing arm, the fifth flexible hinge, and the sixth flexible hinge is symmetrically arranged with respect to the combined structure formed by the third swing arm, the ninth flexible hinge, and the tenth flexible hinge about the reference plane. The combined structure formed by the second swing arm, the seventh flexible hinge, and the eighth flexible hinge is symmetrically arranged with respect to the combined structure formed by the fourth swing arm, the eleventh flexible hinge, and the twelfth flexible hinge about the reference plane.

[0012] In an optional embodiment of the present invention, a plurality of third limiting parts are further included, each of the third limiting parts being used to limit the swing stroke of the first swing arm, the second swing arm, the third swing arm, and the fourth swing arm when the first active part and the second active part move away from each other.

[0013] In an optional embodiment of the present invention, the micro-motion piezoelectric motor includes a stator, a mover movably disposed relative to the stator along the first direction, and a piezoelectric device disposed between the stator and the mover for driving the mover to move along the first direction. The stator is fixedly disposed relative to the first active part, and the mover is fixedly disposed relative to the second active part. An elastic element is provided between the first active part and the second active part, and the elastic element is configured such that its elastic force can drive the first active part and the second active part to move closer to each other.

[0014] To achieve the above and other related objectives, the present invention also provides a foot-driving control system, comprising: The aforementioned driving foot, and A detection element is disposed on the first active part and / or the second active part, and the detection element is used to detect the relative displacement between the first active part and the second active part; A controller is electrically connected to the detection element and the micro-piezoelectric motor, and the controller is configured to control the micro-piezoelectric motor to operate according to the detection signal of the detection element.

[0015] To achieve the above and other related objectives, the present invention also provides a motion platform, comprising: Fasteners; The movable component is suspended below the fixed component by multiple drive feet.

[0016] To achieve the above and other related objectives, the present invention also provides a POB optical engine, comprising: The aforementioned motion platform; and A reflector is mounted on the movable component.

[0017] The technical advantages of this invention are as follows: The driving foot provided by this invention achieves a completely symmetrical transmission path through symmetrically arranged first and second driving parts, and vertically converted first and second driven parts, in conjunction with a micro-piezoelectric motor located in the middle. Specifically, the micro-piezoelectric motor drives the first and second driving parts to open and close symmetrically along a first direction. This symmetrical motion is then converted by the transmission part into the first and second driven parts opening and closing symmetrically along a vertical second direction. Finally, the fixed and movable parts are connected by the first and second mounting seats, respectively. This symmetrical transmission structure fundamentally eliminates the yaw error caused by asymmetrical force, ensuring motion accuracy at the nanometer level. At the same time, using a micro-piezoelectric motor as the driving element, its own driving accuracy is significantly higher than that of traditional driving elements, allowing the transmission part to be designed with a smaller motion reduction ratio. While still achieving the required accuracy at the output end, it greatly improves the output displacement of the driving foot, thus meeting the dual requirements of a six-degree-of-freedom platform with a motion stroke at the micrometer level and motion accuracy at the nanometer level. Attached Figure Description

[0018] Figure 1 This is a partial side view of the POB optical engine provided in an embodiment of the present invention; Figure 2 This is a front view of the driving foot provided in an embodiment of the present invention; Figure 3 yes Figure 2 AA section view; Figure 4 This is a perspective view of the driving foot provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the drive foot control system provided in an embodiment of the present invention; Explanation of reference numerals in the attached drawings: 100, motion platform; 200, reflector; 300, controller; 10, driving foot; 11, first active part; 12, second active part; 13, first driven part; 131, first mounting base; 132, first transition part; 133, second flexible hinge; 134, first flexible hinge; 135, first cantilever; 136, third cantilever; 137, fourth cantilever; 14, second driven part; 141, second mounting base; 142, second transition part; 143, fourth flexible hinge; 144, third flexible hinge; 145, second cantilever; 146, fifth cantilever; 147, sixth cantilever; 15, first Swing arm; 151, Fifth flexible hinge; 152, Sixth flexible hinge; 153, Seventh cantilever; 16, Second swing arm; 161, Seventh flexible hinge; 162, Eighth flexible hinge; 163, Eighth cantilever; 17, Third swing arm; 171, Ninth flexible hinge; 172, Tenth flexible hinge; 173, Ninth cantilever; 18, Fourth swing arm; 181, Eleventh flexible hinge; 182, Twelfth flexible hinge; 183, Tenth cantilever; 19, Micro-motion piezoelectric motor; 191, Stator; 192, Mover; 193, Piezoelectric device; 110, Detection element; 120, Elastic element; 20, Fixed part; 30, Moving part. Detailed Implementation

[0019] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, unless otherwise specified, the following embodiments and features described therein can be combined with each other.

[0020] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the illustrations only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0021] like Figure 1 As shown, the driving foot 10 provided by this invention can be applied to a motion platform 100, especially a six-degree-of-freedom platform, such as the Stewart platform of a POB optical engine. The motion platform 100 includes a fixed component 20 and a movable component 30, with the movable component 30 suspended below the fixed component 20 by multiple driving feet 10. The POB optical engine also includes a reflector 200, which is mounted on the movable component 30. The working principle of the POB optical engine is as follows: the illumination beam passes through a mask, then through the projection lens and the reflector system in the POB, ultimately projecting the mask pattern precisely onto the silicon wafer surface. The reflector, through the six-degree-of-freedom platform, achieves precise positioning, leveling, and protection of the mask pattern within the field of view of the projection lens, while simultaneously controlling the transmission path of the illumination beam. In some solutions, the driving foot employs an asymmetric lever-type motion reduction mechanism. On the one hand, the asymmetric force makes the driving foot prone to swaying during operation, introducing additional position and attitude errors, which seriously affects the motion accuracy of the six-degree-of-freedom platform. On the other hand, the insufficient motion accuracy of the driving element itself forces the motion reduction mechanism to use a large reduction ratio to ensure output accuracy. However, the large reduction ratio also significantly limits the output displacement of the driving foot, thus severely restricting the motion stroke of the six-degree-of-freedom platform. To address this, the present invention provides a driving foot 10, which adopts a symmetrically distributed transmission structure, effectively avoiding swaying while ensuring driving accuracy. Simultaneously, the present invention uses a micro-motion piezoelectric motor drive, improving the driving accuracy of the driving element itself, thereby appropriately reducing the reduction ratio of the motion reduction mechanism and effectively increasing the driving stroke of the driving foot 10, thus balancing the requirements of the six-degree-of-freedom platform for both a hundred-micrometer-level motion stroke and a hundred-nanometer-level motion accuracy.

[0022] The technical solution of the present invention will be described in detail below with reference to specific embodiments: Please see Figure 2As shown, an embodiment of the present invention provides a driving foot 10, which includes: a first active part 11 and a second active part 12 disposed opposite to each other along a first direction X; a first driven part 13 and a second driven part 14 disposed opposite to each other along a second direction Y, wherein the second direction Y is perpendicular to the first direction X; a micro-motion piezoelectric motor 19 disposed between the first active part 11 and the second active part 12, wherein the micro-motion piezoelectric motor 19 is configured to drive the first active part 11 and the second active part 12 to open and close symmetrically about a reference plane P between them, wherein the reference plane P is perpendicular to the first direction X; the first active part 11, the second active part 12, the third active part 13, the fourth active part 14, the fifth active part 15, the sixth active part 16, the seventh active part 17, the eighth active part 18, the ninth active part 19, the eleventh active part 11, the eleventh active part 12, the eleventh active part 11, the eleventh active part 12, the eleventh active part 13, the eleventh active part 14, the eleventh active part 15, the eleventh active part 16, the eleventh active part 17, the eleventh active part 18, the eleventh active part 19, the eleventh active part 11, the eleventh active part 12 ... A transmission unit is provided between the two driving parts 12 and the first driven parts 13 and the second driven parts 14 respectively. The transmission unit is configured to convert the opening / closing action between the first driving part 11 and the second driving part 12 along the first direction X into the opening / closing action between the first driven part 13 and the second driven part 14 along the second direction Y. In the second direction Y, the first driven part 13 is provided with a first mounting seat 131 for connecting the fixing member 20 at one end away from the second driven part 14, and the second driven part 14 is provided with a second mounting seat 141 for connecting the movable member 30 at one end away from the first driven part 13.

[0023] The driving foot 10 provided by the present invention achieves a completely symmetrical transmission path through a symmetrically arranged first active part 11 and second active part 12, and a vertically converted first driven part 13 and second driven part 14, in conjunction with a micro-motion piezoelectric motor 19 located in the middle. Specifically, the micro-motion piezoelectric motor 19 drives the first active part 11 and the second active part 12 to open and close symmetrically along the first direction X. This symmetrical movement is converted by the transmission part into the first driven part 13 and the second driven part 14 opening and closing symmetrically along the vertical second direction Y. Finally, the fixed part 20 and the movable part 30 are connected by the first mounting base 131 and the second mounting base 141, respectively. This symmetrical transmission structure fundamentally eliminates the yaw error caused by asymmetrical force, ensuring motion accuracy at the level of hundreds of nanometers. At the same time, the micro-piezoelectric motor 19 is used as the driving element, and its own driving accuracy is significantly higher than that of traditional driving elements. This allows the transmission part to be designed with a smaller motion reduction ratio. While still achieving the required accuracy at the output end, the output displacement of the drive foot 10 is greatly improved, thus taking into account the dual requirements of hundreds of micrometer-level motion stroke and hundreds of nanometer-level motion accuracy of the six-degree-of-freedom platform.

[0024] Please see Figure 2 , Figure 4As shown, in an optional embodiment of the present invention, a first hinge mechanism is provided between the first driven part 13 and the first mounting base 131, enabling the first driven part 13 to swing relative to the first mounting base 131 about at least a first axis and a second axis, wherein the first axis is perpendicular to the second axis and the first axis and the second axis are perpendicular to the second direction Y; a second hinge mechanism is provided between the second driven part 14 and the second mounting base 141, enabling the second driven part 14 to swing relative to the second mounting base 141 about at least a third axis and a fourth axis, wherein the third axis is perpendicular to the fourth axis and the third axis and the fourth axis are perpendicular to the second direction Y. It should be understood that the movable part 30 of the motion platform 100 not only translates during operation, but also rotates around multiple axes, causing the spatial angles between the two ends of the drive foot 10 and the fixed part 20 and the movable part 30 to change in real time. If a rigid connection is used, the drive foot 10 will be subjected to a forced bending moment, generating additional internal stress and deformation, which will introduce uncontrollable position and posture errors and exacerbate the mechanical fatigue of the internal transmission mechanism of the drive foot 10. In this embodiment, a first hinge mechanism is provided between the first driven part 13 and the first mounting base 131, so that the first driven part 13 can swing around the mutually perpendicular first axis and second axis, while the second driven part 1 A second hinge mechanism is provided between the second driven part 14 and the second mounting base 141, so that the second driven part 14 can swing around the mutually perpendicular third axis and fourth axis, and all swing axes are perpendicular to the main driving direction of the driving foot 10, i.e., the second direction Y. This orthogonal hinge mechanism provided at both ends can passively and adaptively adapt to the changes in the angles at both ends of the driving foot 10, release excess rotational degrees of freedom, and ensure that the driving foot 10 only transmits linear driving displacement and driving force along the second direction Y, without transmitting bending moment and torque. This eliminates the interference internal stress caused by angle changes during the movement of the six-degree-of-freedom platform, and ensures the long-term motion accuracy, reliability and life of the driving foot 10.

[0025] Please see Figure 4As shown, in an optional embodiment of the present invention, the first axis is parallel to the first direction X, the second axis is perpendicular to the first direction X; the third axis is parallel to the first direction X, and the fourth axis is perpendicular to the first direction X. It should be understood that the overall active motion of the driving foot 10 mainly occurs within the plane determined by the first direction X and the second direction Y. By precisely setting the hinge's swing axis to be parallel or orthogonal to this plane, the rotational degrees of freedom released by the hinge are exactly consistent with the passive deflection direction of the driving foot 10 due to platform rotation during operation. This allows it to adapt to angle changes in the most direct way, avoiding the introduction of additional torsional stress or parasitic displacement in unexpected directions. Simultaneously, when the driving foot 10 is integrally machined using wire cutting technology, arranging each hinge axis parallel or perpendicular to the principal axis direction of the machining coordinate system avoids complex spatial avoidance or multiple clamping of the machining tool. All hinge features can be cut in a single clamping, significantly reducing machining difficulty and improving machining accuracy and consistency. Thus, while ensuring the motion accuracy of the six-degree-of-freedom platform and low internal stress, the manufacturability and cost control of the driving foot 10 are achieved.

[0026] It should be noted that in other embodiments of the present invention, without considering the above-mentioned requirements for optimization of additional torsional stress and simplification of wire cutting process, the first axis and the second axis of the first hinge mechanism, as well as the third axis and the fourth axis of the second hinge mechanism, can all be rotated around the second direction Y to any angle. As long as the geometric constraints of being mutually perpendicular and perpendicular to the second direction Y are met, the multi-degree-of-freedom swing compliance function between the first driven part 13 and the first mounting base 131, and between the second driven part 14 and the second mounting base 141 can be realized. Similarly, unnecessary interference internal stress can be avoided in the driving foot 10 during the movement of the six-degree-of-freedom platform.

[0027] Please see Figure 4As shown, in an optional embodiment of the present invention, the first hinge mechanism includes: a rigid first transition portion 132, a plate-shaped first flexible hinge 134 disposed between the first driven portion 13 and the first transition portion 132, and a plate-shaped second flexible hinge 133 disposed between the first transition portion 132 and the first mounting base 131; responsive to the non-deformation state of the first flexible hinge 134 and the second flexible hinge 133, the plate surface of the first flexible hinge 134 is perpendicular to the first axis, and the plate surface of the second flexible hinge 133 is perpendicular to the first axis. The second axis is perpendicular; the second hinge mechanism includes: a rigid second transition portion 142, a plate-shaped third flexible hinge 144 disposed between the second driven portion 14 and the second transition portion 142, and a plate-shaped fourth flexible hinge 143 disposed between the second transition portion 142 and the second mounting base 141; in response to the non-deformation state of the third flexible hinge 144 and the fourth flexible hinge 143, the plate surface of the third flexible hinge 144 is perpendicular to the third axis, and the plate surface of the fourth flexible hinge 143 is perpendicular to the fourth axis. It should be understood that the physical characteristics of the plate-shaped flexible hinge determine that it has low bending stiffness and is easy to flexibly swing in the direction normal to the plate surface, while maintaining high stiffness in the plate extension plane. Each flexible hinge only produces low stiffness compliance for the rotational degree of freedom to be released, while maintaining high stiffness in the main driving direction of the driving foot 10, i.e., the second direction Y. This does not interfere with the angle self-adaptation during the motion of the six-degree-of-freedom platform, and can stably transmit the linear displacement and driving force of the driving foot 10 along the second direction Y, and resist the undesirable deformation caused by external loads. Thus, while realizing the hinge function of no gaps, no friction, and no lubrication, it ensures the load-bearing capacity and motion transmission accuracy of the driving foot 10.

[0028] Please refer to Figure 4. In an optional embodiment of the present invention, in the second direction Y, the first flexible hinge 134 is distributed in a first length interval, the second flexible hinge 133 is distributed in a second length interval, and the first length interval and the second length interval at least partially overlap; in the second direction Y, the third flexible hinge 144 is distributed in a third length interval, the fourth flexible hinge 143 is distributed in a fourth length interval, and the third length interval and the fourth length interval at least partially overlap. It should be understood that if two orthogonal flexible hinges are offset from each other in the second direction Y, the swing center around the first axis and the swing center around the second axis will be located in different positions. When the first driven part 13 swings relative to the first mounting base 131 and rotates around the two axes at the same time, an undesirable translational coupling component will be generated, resulting in additional positional error at the output end of the drive foot 10, affecting the motion accuracy of the six-degree-of-freedom platform. However, this embodiment achieves maximum proximity and even overlap of the spatial positions of the two orthogonal swing axes in the second direction Y by making the length range of the paired flexible hinges at least partially overlap. This ensures that the swing center of the drive foot 10 remains approximately fixed regardless of which direction it swings, eliminating the coupling motion introduced by the axis misalignment. This allows the first hinge mechanism and the second hinge mechanism to achieve true two-degree-of-freedom pure rotational compliance, further ensuring the accuracy of motion transmission by the drive foot 10 and the control accuracy of the six-degree-of-freedom platform.

[0029] Please see Figure 2 , Figure 4 As shown, in an optional embodiment of the present invention, it further includes: a first limiting part for limiting the swing stroke of the first driven part 13 relative to the first mounting base 131; and a second limiting part for limiting the swing stroke of the second driven part 14 relative to the second mounting base 141. It should be understood that in the practical application of a six-degree-of-freedom platform, the driving foot 10 is often not installed vertically but arranged at an angle. The gravitational load of the platform and the components it carries, such as the reflector 200, mainly acts in the vertical direction. When the swing angle of the hinge mechanism is too large, the effective stiffness component of the driving foot 10 along its main driving direction, i.e., the second direction Y, will decrease significantly. At the same time, the support component in the vertical direction will decrease accordingly, resulting in insufficient overall support stiffness of the platform, which in turn affects the motion stability and position holding accuracy. In this embodiment, the maximum swing angle of the first driven part 13 and the second driven part 14 is actively constrained by the limiting part, so as to prevent the driving foot 10 from entering an excessive swing state when working or being impacted. This keeps the working range of the hinge mechanism within the range where the support stiffness meets the requirements, which not only preserves the necessary flexibility of the hinge mechanism to adapt to angle changes, but also prevents the problem of stiffness degradation caused by excessive swing, thus ensuring the stable load-bearing capacity of the six-degree-of-freedom platform during large stroke and high-precision motion.

[0030] Please see Figure 2 , Figure 4 As shown, in a specific embodiment, the first limiting part may be, for example, a plurality of first cantilever arms 135 respectively disposed on both sides of the first flexible hinge 134 and the second flexible hinge 133, and the second limiting part may be, for example, a plurality of second cantilever arms 145 respectively disposed on both sides of the third flexible hinge 144 and the fourth flexible hinge 143. The first cantilever arms 135 and the second cantilever arms 145 may be integrally formed with other structures of the driving foot 10 by wire cutting process.

[0031] Please see Figure 2 , Figure 4 As shown, in an optional embodiment of the present invention, the transmission unit includes: a first swing arm 15, which is hinged to the first driving part 11 via a fifth flexible hinge 151 and to the first driven part 13 via a sixth flexible hinge 152; a second swing arm 16, which is hinged to the first driving part 11 via a seventh flexible hinge 161 and to the second driven part 14 via an eighth flexible hinge 162; a third swing arm 17, which is hinged to the second driving part 12 via a ninth flexible hinge 171 and to the first driven part 13 via a tenth flexible hinge 172; and a fourth swing arm 18, which is hinged to the second driving part 12 via an eleventh flexible hinge 181 and to the second driven part 14 via a twelfth flexible hinge 182. It should be understood that when the micro-piezoelectric motor 19 drives the first active part 11 and the second active part 12 to open and close symmetrically about the reference plane P, each swing arm rotates around the flexible hinges at both ends, accurately converting the symmetrical linear motion of the active part along the first direction X into the symmetrical linear motion of the first driven part 13 and the second driven part 14 along the second direction Y. All flexible hinges are gapless and frictionless flexible structures, avoiding the gap error and creep phenomenon of traditional kinematic pairs. At the same time, the completely symmetrical arrangement of the four swing arms ensures that the force flow distribution is uniform and there is no off-center load during the transmission process, further eliminating the possibility of generating sway torque from the transmission link itself. In addition, each swing arm is connected by flexible hinges at both ends, so that the entire transmission part can move in a coordinated manner with the micro-deformation of the drive foot 10, without relative sliding parts, realizing high rigidity, high precision, and high repeatability of motion reduction transmission, and ensuring the realization of motion accuracy at the hundred-nanometer level.

[0032] Please see Figure 2 , Figure 4As shown, in an optional embodiment of the present invention, the fifth flexible hinge 151, the sixth flexible hinge 152, the seventh flexible hinge 161, the eighth flexible hinge 162, the ninth flexible hinge 171, the tenth flexible hinge 172, the eleventh flexible hinge 181, and the twelfth flexible hinge 182 are plate-like structures. In response to the non-deformation state of the fifth flexible hinge 151, the sixth flexible hinge 152, the seventh flexible hinge 161, the eighth flexible hinge 162, the ninth flexible hinge 171, the tenth flexible hinge 172, the eleventh flexible hinge 181, and the twelfth flexible hinge 182, their plate surfaces are parallel to the third direction Z. The third direction Z is perpendicular to the first direction X and the second direction Y; the combined structure formed by the first swing arm 15, the fifth flexible hinge 151, and the sixth flexible hinge 152 is symmetrically arranged with respect to the reference plane P with respect to the combined structure formed by the third swing arm 17, the ninth flexible hinge 171, and the tenth flexible hinge 172; the combined structure formed by the second swing arm 16, the seventh flexible hinge 161, the eighth flexible hinge 162, and the combined structure formed by the fourth swing arm 18, the eleventh flexible hinge 181, and the twelfth flexible hinge 182 is symmetrically arranged with respect to the reference plane P. In this embodiment, the plate surface of each flexible hinge is set to be parallel to the third direction Z, so that each flexible hinge has low bending stiffness in the normal direction of its plate surface to allow the swing arm to swing smoothly, while maintaining high stiffness in the plate extension direction, thereby constraining the deformation of the drive foot 10 in the third direction Z and preventing the moving part 30 from generating undesirable lateral displacement and torsion. At the same time, the symmetrical arrangement of the above two sets of combined structures ensures that during the symmetrical opening and closing process of the first active part 11 and the second active part 12, the first driven part 13 and the second driven part 14 only generate precise symmetrical opening and closing movements along the second direction Y, without introducing additional displacement or oscillation. The drive foot 10 is constrained to output only the extension and retraction degree of freedom along the second direction Y, thereby ensuring motion decoupling when each drive foot 10 in the six-degree-of-freedom platform works independently and improving control accuracy.

[0033] Please see Figure 2As shown, in an optional embodiment of the present invention, a plurality of third limiting parts are further included, each of which is used to limit the swing stroke of the first swing arm 15, the second swing arm 16, the third swing arm 17, and the fourth swing arm 18 when the first active part 11 and the second active part 12 move away from each other. It should be understood that when the micro-piezoelectric motor 19 drives the first active part 11 and the second active part 12 to open symmetrically, each swing arm swings outward around the flexible hinges at both ends. Within the normal driving stroke range, the swing angle of the swing arm is within the elastic safety zone of the flexible hinge. If the active part moves too far away due to external impact, abnormal control, or extreme working conditions, the swing arm will exceed the allowable deformation angle of the flexible hinge, thereby causing plastic deformation or fatigue fracture of the flexible hinge. The third limiting part actively limits the maximum swing angle of each swing arm through physical interference, contacts the swing arm before it reaches the safety boundary and prevents further swinging, thereby protecting the flexible hinge from overload and preventing the transmission part from losing motion accuracy or suffering irreversible damage due to excessive deformation. This ensures the structural integrity and long-term reliability of the drive foot 10 under abnormal working conditions.

[0034] Please see Figure 2As shown, in a specific embodiment, the third limiting part may include, for example, a third cantilever 136 and a fourth cantilever 137 respectively suspended outside the sixth flexible hinge 152 and the tenth flexible hinge 172 on the first driven part 13; a fifth cantilever 146 and a sixth cantilever 147 respectively suspended outside the eighth flexible hinge 162 and the twelfth flexible hinge 182 on the second driven part 14; a seventh cantilever 153 suspended outside the fifth flexible hinge 151 on the first swing arm 15; an eighth cantilever 163 suspended outside the seventh flexible hinge 161 on the second swing arm 16; a ninth cantilever 173 suspended outside the ninth flexible hinge 171 on the third swing arm 17; and a tenth cantilever 183 suspended outside the eleventh flexible hinge 181 on the fourth swing arm 18. These cantilever arms can be integrally formed with other structures of the driving foot 10 by wire cutting. It should be noted that the specific implementation of the third limiting part by setting cantilever arms on each swing arm and each driven part is merely an exemplary description of the present invention and is not a limitation on its protection scope. In other embodiments of the present invention, the third limiting part may not be limited to the above-mentioned cantilever structure and its arrangement position. For example, limiting bosses, limiting pins, independently fixed blocks or other forms of mechanical limiting structures may be set at any reasonable position of the swing arm, on the driving part, on the driven part, or on other adjacent components of the driving foot 10. As long as the first driving part 11 and the second driving part 12 can make interference contact with the corresponding swing arm at a preset limit swing angle when they are far apart to prevent further swing, the same overswing protection function can be achieved. All equivalent or simple variations of the limiting method implemented based on the symmetrical transmission structure and flexible hinge overswing protection concept disclosed in the present invention are within the scope of the technical solutions covered by the present invention.

[0035] Please see Figure 2 , Figure 3 , Figure 4As shown, in an optional embodiment of the present invention, the micro-motion piezoelectric motor 19 includes a stator 191, a mover 192 movably disposed relative to the stator 191 along the first direction X, and a piezoelectric device 193 disposed between the stator 191 and the mover 192 for driving the mover 192 to move along the first direction X. The stator 191 is fixedly disposed relative to the first active part 11, and the mover 192 is fixedly disposed relative to the second active part 12. An elastic element 120 is provided between the first active part 11 and the second active part 12, and the elastic element 120 is configured such that its elastic force can drive the first active part 11 and the second active part 12 to move closer to each other. The micro-motion piezoelectric motor 19 provided in this embodiment can specifically adopt the form of a inchworm motor. The stepping motion of the mover 192 relative to the stator 191 is achieved through the alternating clamping and extension of the piezoelectric device 193. It combines the nanometer-level resolution of piezoelectric ceramics with the large stroke capability formed by step accumulation, and simultaneously meets the dual requirements of hundreds of nanometer-level precision and hundreds of micrometer-level stroke. The constant preload provided by the elastic element 120 ensures that the first active part 11 and the second active part 12 are always subjected to a preload that keeps them close to each other. This maintains continuous contact between the active part and the motor output end during each step of the inchworm motor's drive process, completely eliminating the backlash and backlash errors that may occur in traditional transmission chains due to the switching of forward and reverse directions. This ensures that every tiny displacement of the motor output can be transmitted to the transmission part without loss, further guaranteeing the motion accuracy and repeatability of the drive foot 10.

[0036] Please see Figure 2 , Figure 5As shown, the present invention also provides a drive foot control system, including the drive foot 10, a detection element 110, and a controller 300. The detection element 110 is disposed on the first active part 11 and / or the second active part 12, and the detection element 110 is used to detect the relative displacement between the first active part 11 and the second active part 12. The controller 300 is electrically connected to the detection element 110 and the micro-motion piezoelectric motor 19, and the controller 300 is configured to control the micro-motion piezoelectric motor 19 to operate according to the detection signal of the detection element 110. It should be understood that although the micro-piezoelectric motor 19 has high resolution and large stroke characteristics, its stepper drive mode is susceptible to open-loop positioning errors caused by factors such as temperature changes, load fluctuations and long-term creep. By directly integrating the detection element 110 into the drive source position of the active part, the actual relative displacement between the first active part 11 and the second active part 12 can be obtained in real time, and a closed-loop control system can be formed using this as feedback. The controller 300 can dynamically correct each step of the micro-piezoelectric motor 19, compensate for deviations caused by external interference and nonlinear factors, and thus converge the motion accuracy of the active part to the resolution limit of the detection element 110. Since there is a definite reduction ratio between the final output displacement of the driven foot 10 and the displacement of the active part, the high-precision closed-loop control of the active part will be directly mapped to a higher-precision motion at the output end, ultimately ensuring that the driven foot 10 can still stably achieve a motion accuracy of hundreds of nanometers within a stroke range of hundreds of micrometers.

[0037] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

[0038] Throughout this description, numerous specific details, such as examples of components and / or methods, are provided to provide a complete understanding of embodiments of the invention. However, those skilled in the art will recognize that embodiments of the invention may be practiced without one or more of these specific details or by other devices, systems, components, methods, parts, materials, components, etc. In other instances, well-known structures, materials, or operations have not been specifically shown or described in detail to avoid obscuring aspects of embodiments of the invention.

Claims

1. A driving foot, characterized in that, include: A first active unit (11) and a second active unit (12) are arranged opposite to each other along a first direction (X); A first driven part (13) and a second driven part (14) are arranged opposite each other along a second direction (Y), the second direction (Y) being perpendicular to the first direction (X); A micro-motion piezoelectric motor (19) is disposed between the first active part (11) and the second active part (12). The micro-motion piezoelectric motor (19) is configured to drive the first active part (11) and the second active part (12) to open and close symmetrically about a reference plane (P) between them. The reference plane (P) is perpendicular to the first direction (X). A transmission unit is provided between the first active part (11), the second active part (12) and the first driven part (13), the second driven part (14), respectively. The transmission unit is configured to convert the opening / closing action between the first active part (11) and the second active part (12) along the first direction (X) into the opening / closing action between the first driven part (13) and the second driven part (14) along the second direction (Y). In the second direction (Y), the first driven part (13) is provided with a first mounting seat (131) for connecting an external fastener (20) at one end away from the second driven part (14), and the second driven part (14) is provided with a second mounting seat (141) for connecting an external movable part (30) at one end away from the first driven part (13).

2. The driving foot according to claim 1, characterized in that, A first hinge mechanism is provided between the first driven part (13) and the first mounting base (131) to enable the first driven part (13) to swing about at least a first axis and a second axis relative to the first mounting base (131), wherein the first axis is perpendicular to the second axis and the first axis and the second axis are perpendicular to the second direction (Y); A second hinge mechanism is provided between the second driven part (14) and the second mounting base (141) to enable the second driven part (14) to swing about at least a third axis and a fourth axis relative to the second mounting base (141), wherein the third axis is perpendicular to the fourth axis and the third axis and the fourth axis are perpendicular to the second direction (Y).

3. The driving foot according to claim 2, characterized in that, The first axis is parallel to the first direction (X), and the second axis is perpendicular to the first direction (X); The third axis is parallel to the first direction (X), and the fourth axis is perpendicular to the first direction (X).

4. The driving foot according to claim 2, characterized in that, The first hinge mechanism includes: a rigid first transition portion (132), a plate-shaped first flexible hinge (134) disposed between the first driven portion (13) and the first transition portion (132), and a plate-shaped second flexible hinge (133) disposed between the first transition portion (132) and the first mounting base (131); in response to the non-deformation state of the first flexible hinge (134) and the second flexible hinge (133), the plate surface of the first flexible hinge (134) is perpendicular to the first axis, and the plate surface of the second flexible hinge (133) is perpendicular to the second axis; The second hinge mechanism includes: a rigid second transition portion (142), a plate-shaped third flexible hinge (144) disposed between the second driven portion (14) and the second transition portion (142), and a plate-shaped fourth flexible hinge (143) disposed between the second transition portion (142) and the second mounting base (141); in response to the non-deformation state of the third flexible hinge (144) and the fourth flexible hinge (143), the plate surface of the third flexible hinge (144) is perpendicular to the third axis, and the plate surface of the fourth flexible hinge (143) is perpendicular to the fourth axis.

5. The driving foot according to claim 4, characterized in that, In the second direction (Y), the first flexible hinge (134) is distributed in a first length interval, and the second flexible hinge (133) is distributed in a second length interval, wherein the first length interval and the second length interval at least partially overlap. In the second direction (Y), the third flexible hinge (144) is distributed in the third length interval, and the fourth flexible hinge (143) is distributed in the fourth length interval, wherein the third length interval and the fourth length interval at least partially overlap.

6. The driving foot according to claim 2, characterized in that, Also includes: The first limiting part is used to limit the swing stroke of the first driven part (13) relative to the first mounting base (131); as well as The second limiting part is used to limit the swing stroke of the second driven part (14) relative to the second mounting base (141).

7. The driving foot according to claim 1, characterized in that, The transmission unit includes: The first swing arm (15) is hinged to the first active part (11) via the fifth flexible hinge (151), and the first swing arm (15) is hinged to the first driven part (13) via the sixth flexible hinge (152). The second swing arm (16) is hinged to the first active part (11) via the seventh flexible hinge (161), and the second swing arm (16) is hinged to the second driven part (14) via the eighth flexible hinge (162). The third swing arm (17) is hinged to the second active part (12) via the ninth flexible hinge (171), and the third swing arm (17) is hinged to the first driven part (13) via the tenth flexible hinge (172). The fourth swing arm (18) is hinged to the second active part (12) via the eleventh flexible hinge (181) and to the second driven part (14) via the twelfth flexible hinge (182).

8. The driving foot according to claim 7, characterized in that, The fifth flexible hinge (151), sixth flexible hinge (152), seventh flexible hinge (161), eighth flexible hinge (162), ninth flexible hinge (171), tenth flexible hinge (172), eleventh flexible hinge (181), and twelfth flexible hinge (182) are plate-like structures. In response to the non-deformation state of the fifth flexible hinge (151), sixth flexible hinge (152), seventh flexible hinge (161), eighth flexible hinge (162), ninth flexible hinge (171), tenth flexible hinge (172), eleventh flexible hinge (181), and twelfth flexible hinge (182), their plate surfaces are parallel to a third direction (Z). The first swing arm (15), the fifth flexible hinge (151), and the sixth flexible hinge (152) are perpendicular to the first direction (X) and the second direction (Y); the combined structure formed by the first swing arm (15), the fifth flexible hinge (151), and the sixth flexible hinge (152) is symmetrically arranged with respect to the reference plane (P) with respect to the combined structure formed by the third swing arm (17), the ninth flexible hinge (171), and the tenth flexible hinge (172); the combined structure formed by the second swing arm (16), the seventh flexible hinge (161), and the eighth flexible hinge (162) is symmetrically arranged with respect to the reference plane (P) with respect to the combined structure formed by the fourth swing arm (18), the eleventh flexible hinge (181), and the twelfth flexible hinge (182).

9. The driving foot according to claim 7, characterized in that, It also includes a plurality of third limiting parts, each of which is used to limit the swing stroke of the first swing arm (15), the second swing arm (16), the third swing arm (17), and the fourth swing arm (18) when the first active part (11) and the second active part (12) move away from each other.

10. The driving foot according to claim 1, characterized in that, The micro-motion piezoelectric motor (19) includes a stator (191), a mover (192) movably disposed relative to the stator (191) along the first direction (X), and a piezoelectric device (193) disposed between the stator (191) and the mover (192) for driving the mover (192) to move along the first direction (X). The stator (191) is fixedly disposed relative to the first active part (11), and the mover (192) is fixedly disposed relative to the second active part (12). An elastic element (120) is provided between the first active part (11) and the second active part (12), and the elastic element (120) is configured such that its elastic force can drive the first active part (11) and the second active part (12) to move closer to each other.

11. A foot-driving control system, characterized in that, include: The driving foot (10) according to any one of claims 1 to 10, and A detection element (110) is disposed on the first active part (11) and / or the second active part (12), the detection element (110) being used to detect the relative displacement between the first active part (11) and the second active part (12); A controller (300) is electrically connected to the detection element (110) and the micro-piezoelectric motor (19), and the controller (300) is configured to control the micro-piezoelectric motor (19) to operate according to the detection signal of the detection element (110).

12. A motion platform, characterized in that, include: Fastener (20); The movable part (30) is suspended below the fixed part (20) by the drive foot (10) as described in any one of claims 1 to 10.

13. A POB optical engine, characterized in that, include: The motion platform (100) according to claim 12; and A reflector (200) is mounted on the movable part (30).

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