A rotary positioning platform and a spatial positioning platform

Abstract

The application provides a rotary positioning platform and a space positioning platform, which comprises a base (110), a moving platform (120), a plurality of support branches (130) and a plurality of driving devices (140); one end of the support branch (130) is connected with the back surface (122) of the moving platform (120) through a first joint (131), the other end of the support branch (130) is connected with the base (110) through a second joint (132), and the extension lines of the central axes of the plurality of support branches (130) intersect at a point; the first joint (131) is used as a spherical pair, and the second joint (132) is used as a U-shaped pair; the plurality of driving devices (140) are arranged between the moving platform (120) and the base (110) respectively, and the plurality of driving devices (140) are used for rotary operation of the moving platform (120).

Description

Technical Field

[0001] This application relates to the field of precision manufacturing, and more specifically, to a rotary positioning platform and a spatial positioning platform. Background Technology

[0002] In most positioning platforms, translation and rotation are often intertwined, leading to mutual interference between degrees of freedom, increasing control complexity and the risk of error accumulation. Decoupled positioning platforms, including cascaded linear and rotary positioning platforms, can independently control translation and rotation, avoiding vibration and hysteresis caused by multi-degree-of-freedom linkage, thereby improving the overall system performance and reliability. Furthermore, decoupled positioning platforms simplify the design and implementation of control algorithms, reduce the requirements on the control system, and make the system easier to debug and maintain.

[0003] Existing decoupled positioning platforms are primarily designed to maintain high sensitivity while increasing the travel of each degree of freedom to meet the demands of high-precision and multi-tasking applications. These mechanisms are complex, increasing not only their size but also the difficulty of maintenance, thus raising long-term maintenance costs. However, in some applications in precision manufacturing fields such as chip manufacturing, the rotational degrees of freedom of the positioning platform have smaller travel distances, requiring a simpler, more sensitive, and shorter-travel rotary positioning platform. Summary of the Invention

[0004] This application provides a rotary positioning platform and a spatial positioning platform, with the aim of obtaining a highly sensitive, short-stroke rotary positioning platform.

[0005] In a first aspect, a rotary positioning platform is provided, comprising a base, a movable platform, multiple support chains, and multiple drive devices. One end of each support chain is connected to the back of the movable platform via a first joint, and the other end of each support chain is connected to the base via a second joint. The extensions of the central axes of the multiple support chains intersect at a point. The first joint serves as a spherical joint, and the second joint serves as a U-shaped joint. The multiple drive devices are respectively disposed between the movable platform and the base, and are used to rotate the movable platform.

[0006] In this embodiment, the rotary positioning platform includes multiple parallel support chains. The positional and constraint relationships between the multiple support chains can improve the stability and sensitivity of the mobile platform, thereby obtaining a highly sensitive short-stroke rotary positioning platform.

[0007] In some implementations of the first aspect, the extensions of the central axes of the multiple support chains intersect at the center of the loading surface of the mobile platform.

[0008] In the design of a positioning platform, if the center of the platform's loading surface does not coincide with the intersection point of the extended lines of the central axes of multiple support chains, it will lead to the coupling of translation and rotation. In this implementation, the rotation center of the mobile platform can be adjusted by the positional relationship between the parallel support chains, thereby reducing the coupling between translation and rotation of the mobile platform.

[0009] In some implementations of the first aspect, a plurality of driving devices are used to output driving forces in any direction to rotate the mobile platform, wherein at least three of the driving forces generate torques about the center of the mobile platform that are linearly independent.

[0010] In this implementation, the torques generated by at least three driving forces about the center of the mobile platform are linearly independent, which can reduce the coupling between translation and rotation of the mobile platform and simplify the complexity of the drive control algorithm.

[0011] In some implementations of the first aspect, multiple drive devices are used to translate along a first direction or a second direction to perform a rotational operation on the mobile platform, wherein the first direction is perpendicular to the surface of the base and the second direction is parallel to the surface of the base.

[0012] In this implementation, the degree of freedom analysis and motion mode of translational motion are relatively intuitive and easy to understand and model in short-stroke and low-load application scenarios, which can simplify the complexity of the drive control algorithm.

[0013] In some implementations of the first aspect, the drive device includes a split voice coil motor, the mover of which is used for translation along a first direction or a second direction, the mover being fixedly connected to the back of the moving platform, and the stator of the split voice coil motor being fixedly connected to the surface of the base.

[0014] In this implementation, there is a gap between the stator and mover of the split voice coil motor, which allows the mover to deviate slightly in the non-motion direction, enabling the moving platform to rotate smoothly and efficiently.

[0015] In some implementations of the first aspect, the first joints of the multiple support chains form a first uniform circumferential distribution, the center of which coincides with the center of the back of the mobile platform.

[0016] In some implementations of the first aspect, the second joints of the multiple supporting branches form a second uniform circumferential distribution, the center of which coincides with the center of the surface of the base.

[0017] In some implementations of the first aspect, the centers of the stators of multiple split voice coil motors form a third uniform circumferential distribution, the center of which coincides with the center of the surface of the base.

[0018] This implementation approach can improve the stability of the mobile platform and simplify the complexity of the drive control algorithm.

[0019] In some implementations of the first aspect, the second joint includes a Hooke hinge that rotates along a first direction and a third direction, the base of the Hooke hinge being fixedly connected to the surface of the base of the rotary positioning platform, wherein the third direction is perpendicular to the central axis of the support branch connected to the second joint and parallel to the surface of the base.

[0020] In this implementation, the Hooke's hinge of the second joint can improve the stability of the second joint.

[0021] In some implementations of the first aspect, the first joint includes a Hooke hinge that rotates along a first direction and a third direction, and the support chain is a flexible chain that is capable of twisting along a central axis for rotating the first joint along a fourth direction, wherein the fourth direction is perpendicular to the third direction and parallel to the surface of the base.

[0022] In this implementation, the flexible branch is used to increase the rotational stroke of the rotary positioning platform and also to achieve the rotation of the roll angle in the first joint, which can improve the stability of the first joint.

[0023] In some implementations of the first aspect, the first joint includes a bearing that rotates in a fourth direction and a Hooke's hinge that rotates in the first and third directions, the end face of the bearing being fixedly connected to the base of the Hooke's hinge, wherein the fourth direction is perpendicular to the third direction and parallel to the surface of the base.

[0024] On the one hand, if a ball joint is used directly to realize the first joint, the stability of the yaw and pitch angles will be low. On the other hand, it is quite complex to realize the rotation of the roll angle in a joint formed only by a Hooke joint. In this implementation, the Hooke joint of the first joint can improve the stability of the yaw and pitch angles, and the bearing is used to realize the rotation of the roll angle, thereby improving the stability of the first joint.

[0025] Secondly, a spatial positioning platform is provided, including a linear positioning platform connected in series and a rotary positioning platform as described in any implementation of the first aspect.

[0026] In some implementations of the second aspect, the loading surface of the linear positioning platform is fixedly connected to the base of the rotary positioning platform. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of a rotary positioning platform provided in an embodiment of this application.

[0028] Figure 2 This is a front view of a rotary positioning platform provided in an embodiment of this application.

[0029] Figure 3 This is a schematic diagram of the relative coordinate system of a rotating positioning platform provided in an embodiment of this application.

[0030] Figure 4 This is a schematic diagram of the structure of a linear positioning platform provided in an embodiment of this application.

[0031] Figure 5 This is a schematic diagram of the structure of a spatial positioning platform provided in an embodiment of this application. Detailed Implementation

[0032] First, let me explain the technical terms related to this application.

[0033] The linear independence of vectors means that for n vectors of the same dimension, if no single vector can be expressed as a linear combination of the other n-1 vectors, then these n vectors are linearly independent.

[0034] In the scenario of a rigid body rotating about a fixed axis, the "direction of the torque generated by the force about the center of rotation" refers to the direction that is orthogonal to both the direction of the force and the direction of the lever arm (i.e., the direction from the center of rotation to the point where the force is applied), provided that the direction of the force and the direction of the lever arm are not collinear. If the center of rotation and the point where the force is applied coincide, there is no effective lever arm, and therefore no torque is generated.

[0035] The heading angle, pitch angle, and roll angle are three basic angles that describe the attitude of a vehicle or ship in three-dimensional space.

[0036] The yaw angle is the angle between the longitudinal axis of a vessel and a reference direction in the horizontal plane. When true north is chosen as the reference direction, if a ship is sailing directly north, its yaw angle is 0 degrees or 360 degrees; if it is sailing east, the yaw angle is 90 degrees.

[0037] The pitch angle represents the angle between the longitudinal axis of a vehicle and the horizontal plane. A positive pitch angle occurs when the front of the vehicle is tilted upwards, and a negative pitch angle occurs when the front is tilted downwards. The pitch angle describes the degree of tilt of the vehicle along its longitudinal axis (from front to back). For example, an aircraft will have a positive pitch angle during climb and a negative pitch angle during descent.

[0038] Roll angle refers to the angle at which a vehicle rotates around its longitudinal axis, that is, the degree of tilt from one side to the other. When the vehicle tilts downward to the right, the roll angle is negative; when it tilts downward to the left, the roll angle is positive. For aircraft, roll angle is generated when they turn or adjust their flight attitude. For ships, roll angle is the result of the ship rolling from side to side due to the action of waves.

[0039] A uniform circular distribution, also known as an equidistant circular distribution, means that multiple points are distributed along a uniform circle, with the arc length between adjacent points being equal and the angular interval between adjacent points being equal.

[0040] The elastic limit is the maximum stress a material can withstand without permanent deformation; the elastic range is the maximum amount of deformation a material can undergo within its elastic range; and the elastic modulus is the ratio of stress to strain within the elastic range, reflecting the material's ability to resist elastic deformation. The larger the elastic modulus, the more difficult it is for the material to undergo elastic deformation.

[0041] Kinematic pairs are a theoretical concept in mechanical engineering that describes the types of relative motion that can occur between two rigid bodies. They are defined by analyzing the geometry and relative position of the contact surfaces of the two rigid bodies. A joint is the actual physical connection point between two or more components in a mechanical system, allowing some form of relative motion between these components. In other words, a joint is the physical realization of a kinematic pair.

[0042] A kinematic chain is a system consisting of several rigid bodies connected by kinematic pairs. It is used to transmit motion and force to achieve complex multi-degree-of-freedom motion. In a kinematic chain, a link is a rigid part that makes up the chain. Each link is an independent rigid body that is connected to other links or bases through kinematic pairs.

[0043] A flexible link is a special type of link widely used in parallel mechanisms and other precision mechanical systems. It achieves specific motion characteristics and functions by replacing traditional rigid connections with flexible materials or structural designs. Unlike rigid links, flexible links can undergo controlled elastic deformation while bearing loads. This characteristic enables them to provide high-precision position and attitude control while reducing friction and wear during motion. Flexible links are typically made of materials with high elastic modulus (such as metal sheets, composite materials, or special alloys), or achieve the desired flexible behavior through clever geometric designs (such as bending beams, helical springs, or diaphragms). They can be used to fine-tune the motion of systems, compensate for manufacturing and assembly errors, and improve the response speed and stability of systems.

[0044] The most common type of Hooke joint is the vertical Hooke joint, also known as a universal joint. Unless otherwise specified, Hooke joint, vertical Hooke joint, and universal joint have similar meanings. Specifically, a Hooke joint consists of two revolute joints connected in series with intersecting and perpendicular central axes. It has two rotational degrees of freedom, typically pitch and yaw, while roll rotation is restricted. In mechanical systems, Hooke joints are commonly used to connect two components that need to rotate relative to each other, such as the connection between a driveshaft and a steering knuckle. Therefore, they are widely used in applications requiring precise control of rotation angle and direction. Furthermore, the kinematic pair achieved by a Hooke joint is called a U-joint.

[0045] Flexible Hooke joints replace traditional rigid components with flexible materials or structures, enabling high-precision, low-friction, and compact rotary motion transmission. Compared to traditional Hooke joints, flexible Hooke joints utilize elastic deformation to compensate for angular misalignment between central axes, providing smoother and more stable motion performance while maintaining high strength and durability. These joints are typically made of materials with high elastic modulus (such as special alloys, composite materials, or high-performance plastics), or achieve the desired flexibility through clever geometric designs (such as bellows, helical springs, or diaphragms). Flexible Hooke joints effectively reduce shock and vibration during motion, improving system response speed and positioning accuracy, making them particularly suitable for applications requiring high precision and stability.

[0046] A spherical joint is a type of joint widely used in mechanical engineering. It allows two connected components to rotate in three mutually perpendicular directions, thus achieving full-range, multi-degree-of-freedom motion. A spherical joint consists of a spherical part (ball head) and a mating concave seat (socket). The ball head fits into the socket and can rotate freely within a certain range. This design allows the spherical joint to provide three rotational degrees of freedom simultaneously.

[0047] A spherical joint, also known as a ball joint, allows two components to undergo three independent relative rotations about a common sphere center, i.e., rotations in three perpendicular directions. The most common way to achieve a spherical joint is through a ball joint; another type of spherical joint structure uses a Hooke joint and a bearing, etc., in series.

[0048] A three-axis translational pair, also known as a three-degree-of-freedom translational pair, allows two connected rigid bodies to move independently in three mutually perpendicular directions without any rotational motion. Similarly, a two-axis translational pair allows two connected rigid bodies to move independently in two mutually perpendicular directions without any rotational motion.

[0049] A split-type voice coil motor (VCM) consists of a stationary stator and a moving rotor relative to the stator. The stator typically comprises a fixed magnetic circuit system containing permanent magnets and magnetically conductive material. The permanent magnets generate a constant magnetic field, providing the magnetic environment for the rotor's movement. The rotor is usually a plate-shaped, cuboid, or cylindrical component containing a coil (voice coil). When current flows through the voice coil, the voice coil interacts with the magnetic field generated by the stator, producing an electromagnetic force that propels the rotor to move linearly in a predetermined direction. The range and speed of the rotor's movement depend on the magnitude and direction of the current. Some split-type voice coil motors can translate along two axes. Their rotors are typically plate-shaped and can move in two directions parallel to the rotor within grooves formed by the stator. A gap exists between the stator and rotor, allowing for a small range of displacement of the rotor in non-moving directions.

[0050] A parallel mechanism is a multi-degree-of-freedom mechanical system composed of key components such as support links, drive mechanisms, a moving platform, and a base. In this system, the base serves as the fixed part of the entire mechanism, providing a stable foundation. The surface on the moving platform used to support the workpiece, sample, or other object to be manipulated is called the top surface or working surface, while the surface used to connect the links and drive mechanisms is called the bottom surface or connection surface. Multiple support links extend from the base, connecting to the moving platform via joints. These links support the moving platform and maintain its stability, ensuring that the platform can perform predetermined multi-degree-of-freedom movements relative to the base. The drive mechanism can be an electric motor, hydraulic cylinder, piezoelectric actuator, etc., mounted on the base or integrated into the support links, used for precise control of the moving platform's position and orientation.

[0051] Both the drive unit and the moving platform are equipped with a home position, also known as the reference position, zero position, or origin. The home position of the drive unit is used as the origin for kinematic calculations of the drive unit. The home position of the moving platform is usually set as the origin of the absolute coordinate system and is used to describe the relative position of the platform.

[0052] A linear positioning stage, also known as a 3-axis translation stage, allows only translational motion along three mutually perpendicular straight lines, without any rotational motion. A rotary positioning stage, also known as an angular positioning platform or a 3-axis rotational stage, allows only rotational motion around three mutually perpendicular central axes, without any translational motion. A spatial positioning platform refers to a device or system capable of achieving six degrees of freedom (6DOF) motion. This can be achieved directly through a parallel six-DOF mechanism (such as a Stewart platform) or through a decoupled positioning platform.

[0053] In most positioning platforms, translation and rotation are often intertwined, leading to mutual interference between degrees of freedom, increasing control complexity and the risk of error accumulation. Decoupled positioning platforms, including cascaded linear and rotary positioning platforms, can independently control translation and rotation, avoiding vibration and hysteresis caused by multi-degree-of-freedom linkage, thereby improving the overall system performance and reliability. Furthermore, decoupled positioning platforms simplify the design and implementation of control algorithms, reduce the requirements on the control system, and make the system easier to debug and maintain.

[0054] Existing decoupled positioning platforms are primarily designed to maintain high sensitivity while increasing the travel of each degree of freedom to meet the demands of high-precision and multi-tasking applications. These mechanisms are complex, increasing not only their size but also the difficulty of maintenance, thus raising long-term maintenance costs. However, in some applications in precision manufacturing fields such as chip manufacturing, the rotational degrees of freedom of the positioning platform have smaller travel distances, requiring a simpler, more sensitive, and shorter-travel rotary positioning platform.

[0055] In view of this, this application provides a rotary positioning platform and a spatial positioning platform. First, the rotary positioning platform provided in this application will be described with reference to the accompanying drawings.

[0056] Figure 1 A rotary positioning platform is shown. For clarity, an exploded view is used to separate the moving platform and the remaining components of the rotary positioning platform. Specifically, the rotary positioning platform 100 includes a base 110, a moving platform 120, multiple support chains 130, and multiple drive devices 140. One end of each support chain 130 is connected to the back surface 122 of the moving platform 120 via a first joint 131, and the other end of each support chain 130 is connected to the base 110 via a second joint 132. The extensions of the central axes of the multiple support chains 130 intersect at a point. The first joint 131 serves as a spherical joint, and the second joint 132 serves as a U-shaped joint. The multiple drive devices 140 are respectively disposed between the moving platform 120 and the base 110, and are used to rotate the moving platform 120.

[0057] In this embodiment, the rotary positioning platform includes multiple parallel support chains. The positional and constraint relationships between the multiple support chains can improve the stability and sensitivity of the mobile platform, thereby obtaining a highly sensitive short-stroke rotary positioning platform.

[0058] In some embodiments, for ease of explanation, in conjunction with Figure 1The center of the surface 111 of the base 110 is the origin of the absolute coordinate system of the rotary positioning platform 100. The XY plane is the plane on which the surface 111 of the base 110 is located. The XY plane is also called the reference plane, and the Z axis is also called the first direction.

[0059] In some embodiments, a plurality of drive devices 140 are used to output driving forces in any direction to rotate the mobile platform 120, wherein the torque directions generated by at least three of the plurality of drive forces about the center of the mobile platform 120 are linearly independent. Specifically, the position of the at least three drive devices and / or the direction of the output driving force can be adjusted to change the direction of the torque generated by the driving force about the center of the mobile platform. This embodiment does not limit the structure, position, or direction of the driving force of the drive devices.

[0060] In this implementation, the torques generated by at least three driving forces about the center of the mobile platform are linearly independent, which can reduce the coupling between translation and rotation of the mobile platform and simplify the complexity of the drive control algorithm.

[0061] In one possible implementation, multiple drive units 140 are used to translate along a first direction or a second direction to perform a rotational operation on the mobile platform 120, wherein the first direction is perpendicular to the surface 111 of the base 110, and the second direction is parallel to the surface 111 of the base 110. Specifically, the direction parallel to the reference plane (i.e., the second direction) includes the X-axis and Y-axis, and also includes an infinite number of directions in the XY plane, along which the rotation of the mobile platform is a combination of pitch and yaw angles.

[0062] In this implementation, the degree of freedom analysis and motion mode of translational motion are relatively intuitive and easy to understand and model in short-stroke and low-load application scenarios, which can simplify the complexity of the drive control algorithm.

[0063] In one possible implementation, the drive unit 140 includes a split voice coil motor, the mover of which is used for translation along a first direction or a second direction, the mover being fixedly connected to the back surface 122 of the moving platform 120, and the stator of the split voice coil motor being fixedly connected to the surface 111 of the base 110. Specifically, as Figure 1 As shown, the mover of the split voice coil motor can move up and down along the Z-axis, or along the two sides of the groove perpendicular to the stator. The second direction can be considered as the mover translating clockwise or counterclockwise around the Z-axis in the XY plane. When all the split voice coil motors are translating clockwise, the moving platform rotates clockwise. When the mover of the split voice coil motor moves up and down along the Z-axis, it changes the pitch and row angles of the moving platform.

[0064] It should be understood that the stator and mover of the voice coil motor can be fixedly connected to either the back surface 122 of the mobile platform 120 or the base 110, respectively. In a simplest variation, the stator and mover of the voice coil motor can be... Figure 1 The voice coil motor shown rotates along the Z-axis, and its stator is fixedly connected to the back surface 122 of the moving platform 120. This application does not limit the configuration of the voice coil motor.

[0065] In this implementation, there is a gap between the stator and mover of the split voice coil motor, which allows the mover to deviate slightly in the non-motion direction, enabling the moving platform to rotate smoothly and efficiently.

[0066] This application may also employ other types of drive devices. For example, the drive device may include a linear guide, a linear motor, and support chains that are respectively connected to the linear motor and the back surface 122 of the moving platform 120 via spherical joints. This application does not limit the specific implementation of the drive device.

[0067] In one possible implementation, with multiple translation voice coil motors having the same first reference position and each located at the first reference position, the moving platform 120 is located at a second reference position. The first reference position is set based on the travel of the mover of the translation voice coil motor along a first direction. The loading surface 121 and the back surface 122 of the moving platform 120 are parallel to the surface 111 of the base 110, respectively. Specifically, the travel of the mover of all voice coil motors along the Z-axis can be made the same, and the same first reference position can be set for all voice coil motors.

[0068] During normal operation of the mobile platform 120, the target position of the mobile platform 120 is usually not the second reference position, and the intersection point of the extended lines of the central axes of the plurality of support branches 130 changes according to the position of the mover of the translation voice coil motor. In some embodiments, when the mobile platform 120 is located at the second reference position, the extended lines of the central axes of the plurality of support branches 130 intersect at the center of the loading surface 121 of the mobile platform 120. Specifically, as Figure 2 The front view of the rotary positioning platform shown depicts four of the six support chains, their central axes represented by dashed lines. It can be seen that the extensions of these central axes intersect at the center of the loading surface 121 of the moving platform 120.

[0069] In the design of a positioning platform, if the center of the platform's loading surface does not coincide with the intersection point of the extended lines of the central axes of multiple support chains, it will lead to the coupling of translation and rotation. In this implementation, the rotation center of the mobile platform can be adjusted by the positional relationship between the parallel support chains, thereby reducing the coupling between translation and rotation of the mobile platform.

[0070] In one possible implementation, the surface 111 of the base 110, the loading surface 121 of the mobile platform 120, and the back surface 122 of the mobile platform 120 are centrally symmetrical figures. It should be understood that... Figure 1 The surface 111 of the base 110, the loading surface 121 of the mobile platform 120, and the back surface 122 of the mobile platform 120 shown are circular, but they can also be common centrally symmetrical shapes such as squares, regular hexagons, and regular octagons. Of course, in more general embodiments, they can also be any shape, and this application does not limit them.

[0071] In one possible implementation, the first joints 131 of the plurality of support branches 130 form a first uniform circumferential distribution, the center of which coincides with the center of the back surface 122 of the mobile platform 120.

[0072] In one possible implementation, the second joints 132 of the multiple support branches 130 form a second uniform circumferential distribution, the center of which coincides with the center of the surface 111 of the base 110.

[0073] In one possible implementation, the centers of the stators of multiple split voice coil motors form a third uniform circumferential distribution, the center of which coincides with the center of the surface 111 of the base 110.

[0074] This implementation approach can improve the stability of the mobile platform and simplify the complexity of the drive control algorithm.

[0075] In one possible implementation, the second joint 132 includes a Hooke hinge that rotates along a first direction and a third direction. The base of the Hooke hinge is fixedly connected to the surface 111 of the base 110 of the rotary positioning platform, wherein the third direction is perpendicular to the central axis of the support branch 130 connected to the second joint 132 and parallel to the surface 111 of the base 110.

[0076] Specifically, the base of the Hooke's hinge is set on the surface 111 of the base 110, and the direction of the projection of the central axis of the support chain 130 connected to the second joint 132 onto the XY plane of the absolute coordinate system is called the fourth direction. For example... Figure 3 As shown, a relative coordinate system is set at the center of the base of the Hooke hinge. The X2 and Y2 axes of the relative coordinate system are rotated along the Z-axis of the absolute coordinate system to obtain this relative coordinate system. It can be seen that the directions of the XY plane and the Z-axis of the relative coordinate system remain unchanged, and the X2 axis of the relative coordinate system is the fourth direction. Further, assuming the Y2 axis of the relative coordinate system is the third direction, in this embodiment, the rotation of the pitch angle of the Hooke hinge is a rotation along this third direction.

[0077] In this implementation, the Hooke's hinge of the second joint can improve the stability of the second joint.

[0078] In one possible implementation, the first joint 131 includes a Hooke hinge that rotates along a first direction and a third direction, and the support chain 130 is a flexible chain that is capable of twisting along the central axis direction for rotating the first joint 131 along a fourth direction, wherein the fourth direction is perpendicular to the third direction and parallel to the surface 111 of the base 110.

[0079] It should be understood that for the first joint 131 and the second joint 132 on the same support chain 130, the directions of their corresponding relative coordinate systems' X2 axis (and Y2 axis) are the same. According to Figure 3 As in the aforementioned embodiment, the third direction is the Y2 axis of the relative coordinate system, and the fourth direction is the X2 axis of the relative coordinate system. Since the Hooke's joint of the first joint can only achieve rotation along the Z-axis and Y2 axis (rotation of the yaw angle and pitch angle), it is necessary to use the torsion of the flexible branch along the central axis to achieve the rotation of the first joint along the X2 axis, thereby giving the first joint the ability to rotate with three degrees of freedom.

[0080] In this implementation, the flexible branch is used to increase the rotational stroke of the rotary positioning platform and also to achieve the rotation of the roll angle in the first joint, which can improve the stability of the first joint.

[0081] In one possible implementation, the first joint 131 includes a bearing that rotates in a fourth direction and a Hooke's hinge that rotates in the first and third directions. The end face of the bearing is fixedly connected to the base of the Hooke's hinge, wherein the fourth direction is perpendicular to the third direction and parallel to the surface 111 of the base 110. Specifically, the Hooke's hinge is typically used to achieve rotation along the Z-axis and Y2-axis (rotation of the yaw angle and pitch angle). Therefore, a rolling bearing is provided on the Y2Z plane of the first joint to achieve rotation in the X2-axis direction (i.e., rotation of the roll angle), and then a Hooke's hinge is provided on the end face of the rolling bearing to realize the first joint.

[0082] On the one hand, if a ball joint is used directly to realize the first joint, the stability of the yaw and pitch angles will be low. On the other hand, it is quite complex to realize the rotation of the roll angle in a joint formed only by a Hooke joint. In this implementation, the Hooke joint of the first joint can improve the stability of the yaw and pitch angles, and the bearing is used to realize the rotation of the roll angle, thereby improving the stability of the first joint.

[0083] It should be understood that the first joint may also be a modified ball joint with a specific structure, and the embodiments of this application do not limit this.

[0084] It should be understood that the Hooke hinge in the above embodiments can be a flexible Hooke hinge. Selecting a suitable flexible material can precisely limit the travel of the yaw angle and pitch angle of the first joint and the second joint, and further improve the stability of the joint. However, other types of Hooke hinges are also within the scope of protection of this application.

[0085] This application also provides a spatial positioning platform, which includes a linear positioning platform connected in series and the rotary positioning platform 100 described in the foregoing embodiments. Specifically, Figure 4 A linear positioning platform 200 is shown, which includes a base 210, a moving platform 220 and a moving platform 230 disposed within the moving platform 220, wherein the loading surface 231 of the moving platform 230 is used as the loading surface of the linear positioning platform 200.

[0086] In one possible implementation, the loading surface 231 of the linear positioning platform 200 is fixedly connected to the base 110 of the rotary positioning platform 100. Specifically, Figure 5 A spatial positioning platform 300 is shown. This connection method is called serial connection, and the resulting spatial positioning platform is a decoupled positioning platform.

[0087] It should be noted that, in the description of the embodiments of this application, unless otherwise stated, " / " means "or". For example, A / B can mean A or B. The "and / or" in this article is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone.

[0088] In the embodiments of this application, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. Furthermore, in the description of the embodiments of this application, "multiple" refers to two or more, and "at least one" and "one or more" refer to one, two, or more than two. The singular expressions "a," "an," "the," "the," "this," and "this" are intended to also include expressions such as "one or more," unless the context explicitly indicates otherwise.

[0089] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0090] In the description of the embodiments of this application, the terms "upper," "lower," "inner," "outer," "vertical," and "horizontal," etc., indicate orientations or positional relationships relative to the indicated placement of components in the accompanying drawings. It should be understood that these directional terms are relative concepts, used for relative description and clarification, and not to indicate or imply a specific orientation that the device or component must have, or its construction and operation in a specific orientation. They can change accordingly depending on the orientation of the components in the accompanying drawings, and therefore should not be construed as limiting this application. Furthermore, "vertical" in this application is not strictly vertical, but within the allowable error range. "Parallel" is not strictly parallel, but within the allowable error range.

[0091] In this application, the same reference numerals are used to denote the same components. For the same components in this application, only one component may be labeled with a reference numeral in the figures. It should be understood that the reference numerals also apply to other identical components. Furthermore, for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. In addition, the components in the figures are not drawn to actual scale, and the dimensions and sizes of the components shown in the figures are merely exemplary and should not be construed as limiting this application.

[0092] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A rotary positioning platform, characterized in that, The system includes a base (110), a mobile platform (120), multiple support chains (130), and multiple drive devices (140). One end of each support chain (130) is connected to the back surface (122) of the mobile platform (120) via a first joint (131), and the other end of each support chain (130) is connected to the base (110) via a second joint (132). The extensions of the central axes of the multiple support chains (130) intersect at a point. The first joint (131) is used as a spherical joint, and the second joint (132) is used as a U-shaped joint. The multiple drive devices (140) are respectively disposed between the mobile platform (120) and the base (110), and the multiple drive devices (140) are used to rotate the mobile platform (120).

2. The rotary positioning platform according to claim 1, characterized in that, The extensions of the central axes of the plurality of support chains (130) intersect at the center of the loading surface (121) of the mobile platform (120).

3. The rotary positioning platform according to claim 1 or 2, characterized in that, The plurality of drive devices (140) are used to output drive force in any direction to rotate the mobile platform (120), wherein at least three of the plurality of drive forces generate torques about the center of the mobile platform (120) that are linearly independent.

4. The rotary positioning platform according to claim 3, characterized in that, The plurality of drive devices (140) are used to translate along a first direction or a second direction to rotate the mobile platform (120), wherein the first direction is perpendicular to the surface (111) of the base (110) and the second direction is parallel to the surface (111) of the base (110).

5. The rotary positioning platform according to claim 4, characterized in that, The drive device (140) includes a split voice coil motor, the mover of which is used to translate along the first direction or the second direction, the mover being fixedly connected to the back (122) of the moving platform (120), and the stator of which is fixedly connected to the surface (111) of the base (110).

6. The rotary positioning platform according to any one of claims 1 to 5, characterized in that, The first joints (131) of the plurality of support branches (130) form a first uniform circumferential distribution, the center of which coincides with the center of the back (122) of the mobile platform (120).

7. The rotary positioning platform according to any one of claims 1 to 6, characterized in that, The second joints (132) of the plurality of support branches (130) form a second uniform circumferential distribution, the center of which coincides with the center of the surface (111) of the base (110).

8. The rotary positioning platform according to any one of claims 5 to 7, characterized in that, The centers of the stators of the multiple split voice coil motors form a third uniform circumferential distribution, the center of which coincides with the center of the surface (111) of the base (110).

9. The rotary positioning platform according to any one of claims 4 to 8, characterized in that, The second joint (132) includes a Hooke hinge that rotates along the first direction and a third direction. The base of the Hooke hinge is fixedly connected to the surface (111) of the base (110) of the rotary positioning platform, wherein the third direction is perpendicular to the central axis of the support branch (130) connected to the second joint (132) and parallel to the surface (111) of the base (110).

10. The rotary positioning platform according to claim 9, characterized in that, The first joint (131) includes a Hooke hinge that rotates along the first direction and the third direction. The support chain (130) is a flexible chain that is capable of twisting along the central axis direction for rotating the first joint (131) along a fourth direction, wherein the fourth direction is perpendicular to the third direction and parallel to the surface (111) of the base (110).

11. The rotary positioning platform according to claim 9, characterized in that, The first joint (131) includes a bearing that rotates in a fourth direction and a Hooke's hinge that rotates in the first direction and the third direction. The end face of the bearing is fixedly connected to the base of the Hooke's hinge, wherein the fourth direction is perpendicular to the third direction and parallel to the surface (111) of the base (110).

12. A spatial positioning platform, characterized in that, It includes a linear positioning platform (200) connected in series and a rotary positioning platform (100) as described in any one of claims 1 to 11.

13. The spatial positioning platform according to claim 12, characterized in that, The loading surface (231) of the linear positioning platform (200) is fixedly connected to the base (110) of the rotary positioning platform (100).

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