Reaction mass and active isolation cooperative motion platform

Abstract

The application provides a motion platform with reaction mass and active vibration isolation cooperation, which comprises a fixed base, a platform main body, a bearing platform, a gantry, an X-axis main motion assembly, an X-axis reaction mass assembly, a pair of Y-axis main motion assemblies, a pair of Y-axis reaction mass assemblies and a sensor group. The bearing platform is slidingly connected to the platform main body; the gantry is fixed to the platform main body and slidingly connected with a Z-axis execution assembly; the X-axis reaction mass assembly is used for driving the X-axis main motion assembly and absorbing the reaction force and reaction torque thereof; the pair of Y-axis reaction mass assemblies are fixed to the platform main body, respectively driving the corresponding Y-axis main motion assemblies and canceling the inertial reaction force; and the sensor group monitors the positions of each motion assembly and the bearing platform. Through the cooperation of the X and Y direction reaction mass and the vibration isolation unit, the vibration excitation transmitted to the fixed base is effectively reduced, and the positioning accuracy and stability are improved.

Description

Technical Field

[0001] This invention relates to the field of vibration suppression and isolation control technology for high-speed, high-precision motion platforms, and particularly to a motion platform that coordinates a main motion mechanism, a reaction mass mechanism, an active vibration isolation platform, and multi-source sensors. It is suitable for applications with extremely high requirements for vibration isolation and positioning accuracy, such as semiconductor testing, photolithography workpiece stages, precision laser processing, micro-nano manufacturing, and high-precision optical testing. Background Technology

[0002] Currently, in fields such as semiconductor manufacturing, precision inspection, and laser processing, high-precision motion platforms need to achieve rapid and accurate positioning motion in a stable environment at the nanometer or submicrometer level. Existing high-precision motion platforms typically adopt the following structural forms: Firstly, when a motion shaft is directly installed on a passive vibration isolation platform or a rigid base, the reaction force generated by the acceleration and deceleration of the moving parts is directly transmitted to the base or vibration isolation platform, causing low-frequency shaking of the platform and prolonging the stabilization time. Secondly, the method of installing the motion mechanism on the active vibration isolation platform is adopted. However, the vibration isolation system and the motion system are designed independently. The reaction force generated by the acceleration and deceleration of the moving parts is directly transmitted to the vibration isolation platform. The vibration isolation system needs to frequently compensate for motion disturbances. The two interfere with each other, making it difficult to obtain high vibration isolation performance and high motion accuracy at the same time. Third, a marble base with air springs is used for vibration isolation, but this method is mainly for vertical vibration isolation and has limited ability to suppress the horizontal motion recoil component. Fourth, a reaction mass block is used to absorb the recoil force of the moving parts, but traditional reaction masses mostly adopt a passive or fixed proportion compensation method that is "simple in the opposite direction and proportional" to the main motion.

[0003] In particular, due to differences in mass, installation height, mechanical connection path, friction characteristics, and servo dynamics between the main motion component and the reaction component, a single fixed proportional compensation is prone to overcompensation or undercompensation, and may even induce structural resonance. Meanwhile, the long-stroke Y-axis often employs a dual-drive synchronous method with linear motors on both sides. Due to differences in thrust between the two motors, load eccentricity, and structural flexibility, yaw angle deviation and position synchronization errors occur during motion. Electrical synchronization compensation alone has limited response bandwidth, and residual errors are directly transmitted to the workpiece stage. Furthermore, existing recoil suppression methods mostly consider only the resultant inertial force, without simultaneously controlling the inertial torque. Translational and rotational degrees of freedom are not coordinated for vibration isolation, and the platform still exhibits residual pitch, yaw, and roll vibrations.

[0004] Therefore, it is necessary to provide a motion platform that combines reaction mass and active vibration isolation to overcome the above-mentioned defects. Summary of the Invention

[0005] The purpose of this invention is to provide a motion platform that combines reaction mass and active vibration isolation, aiming to solve the problems in the prior art, such as the mutual coupling of active vibration isolation and motion control, the simple reaction compensation method, the difficulty in eliminating the synchronization error of dual-side drive, and the control of only resultant force without controlling torque.

[0006] To achieve the above objectives, the present invention provides a motion platform that combines reaction mass and active vibration isolation, comprising: Fixed base; The platform body is supported on the fixed base by a number of vibration isolation units; A support platform, which is slidably connected to the platform body; A gantry frame, which is fixed to the platform body and slidably connected to a Z-axis actuator; The X-axis main motion assembly is slidably connected to the top of the gantry frame and is used to drive the Z-axis actuator to slide along the X-axis; The X-axis reaction mass assembly is fixed to the top of the gantry frame and is used to drive the X-axis main motion assembly to slide along the X-axis to counteract the inertial reaction force generated when the X-axis main motion assembly accelerates or decelerates. A pair of Y-axis main motion components are slidably connected to the platform body and located on both sides of the bearing platform, respectively, for jointly driving the bearing platform to slide along the Y-axis; A pair of Y-axis reaction mass components, the Y-axis reaction mass components being fixed to the platform body, are used to drive a corresponding Y-axis main motion component to slide along the Y-axis, so as to counteract the inertial reaction force generated when the Y-axis main motion component accelerates or decelerates; A sensor array; the sensor array is used to monitor the positions of the Z-axis actuator, the X-axis main motion assembly, the support platform, and the Y-axis main motion assembly.

[0007] In a preferred embodiment, the platform body includes a support surface and a boss extending upward from a predetermined portion of the support surface; the gantry includes a pair of parallel, spaced columns and a crossbeam mounted on the top of the pair of columns; the bottoms of the pair of columns are vertically fixed to the support surface and are respectively located on both sides of the boss, so that the crossbeam is located above the boss.

[0008] In a preferred embodiment, the X-axis main motion assembly includes a first X-axis guide rail fixed to the gantry, a first X-axis slider slidably held on the first X-axis guide rail, a first X-axis mounting plate fixed to the first X-axis slider, and an X-axis linear motor drive unit fixed to the first X-axis mounting plate; the X-axis reaction mass assembly is used to drive the first X-axis mounting plate to move.

[0009] In a preferred embodiment, the Z-axis actuation component includes a second X-axis guide rail fixed to the gantry, a second X-axis slider slidably held on the second X-axis guide rail, a second X-axis mounting plate fixed to the second X-axis slider, and a Z-axis direct drive motor fixed to the second X-axis mounting plate; the X-axis linear motor drive unit is used to drive the second X-axis mounting plate to move; the Z-axis direct drive motor is used to drive a preset actuation component to move up and down along the Z-axis; the second X-axis guide rail and the first X-axis guide rail are arranged parallel to the X-axis and are respectively located on adjacent vertical sides of the gantry.

[0010] In a preferred embodiment, the sensor group includes a first sensor and a second sensor; both the first sensor and the second sensor are grating rulers; the scale grating of the first sensor is arranged along the X-axis on the gantry, and its reading head is mounted on the first X-axis mounting plate; the scale grating of the second sensor is arranged along the X-axis on the gantry, and its reading head is mounted on the second X-axis mounting plate.

[0011] In a preferred embodiment, each of the Y-axis main motion components includes a first Y-axis guide rail fixed to the boss, a first Y-axis slider slidably held on the first Y-axis guide rail, a first Y-axis mounting plate fixed to the first Y-axis slider, and a Y-axis linear motor drive unit fixed to the first Y-axis mounting plate; the Y-axis reaction mass component is fixed to the support surface and is used to drive the first Y-axis mounting plate to move.

[0012] In a preferred embodiment, the support platform includes a second Y-axis guide rail fixed to the boss, a second Y-axis slider slidably held on the second Y-axis guide rail, a second Y-axis mounting plate fixed to the second Y-axis slider, and a support plate fixed to the second Y-axis mounting plate; the Y-axis linear motor drive unit is used to drive the second Y-axis mounting plate to move; the Z-axis direct drive motor is used to drive a preset execution component to rise and fall along the Z-axis.

[0013] In a preferred embodiment, the sensor group includes a third sensor and a fourth sensor; both the third sensor and the fourth sensor are grating rulers; the scale grating of the third sensor is arranged along the Y-axis on the side of the boss, and its reading head is mounted on the first Y-axis mounting plate; the scale grating of the fourth sensor is arranged along the Y-axis on the boss, and its reading head is mounted on the second Y-axis mounting plate.

[0014] In a preferred embodiment, the number of the fourth sensors is three, which are distributed at intervals along the X-axis at the bottom of the support plate.

[0015] In a preferred embodiment, the bottom of the fixed base is provided with a plurality of height-adjustable support feet.

[0016] The motion platform provided by this invention, which combines reaction mass and active vibration isolation, utilizes independent reaction mass components in both the X and Y axes. These reaction mass components drive their respective main motion components, thus pre-canceling the inertial reaction forces generated by the reaction mass components during acceleration and deceleration of the main motion components at the structural level. Specifically, the X-axis reaction mass component is fixed to the top of the gantry frame and drives the X-axis main motion component to slide along the X-axis; a pair of Y-axis reaction mass components are fixed to the platform body and drive their respective Y-axis main motion components to slide along the Y-axis. Therefore, the reaction force generated during acceleration and deceleration of the main motion components acts first on the reaction mass components, rather than being directly transmitted to the platform body or fixed base. This significantly reduces the vibration excitation level transmitted to the fixed base, shortens the settling time, and improves positioning accuracy. Simultaneously, the platform body is supported on the fixed base by several vibration isolation units, which further attenuate residual disturbances. The reaction mass components and vibration isolation units form a synergistic relationship structurally, jointly enhancing the platform's vibration suppression capability. In addition, the sensor group monitors the positions of the Z-axis actuator, X-axis main motion assembly, load-bearing platform, and Y-axis main motion assembly, providing a structural basis for real-time detection of synchronization error and yaw error in the dual-side dual-drive structure, which helps to improve the position synchronization accuracy and yaw control accuracy of the dual-side drive structure. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A perspective view of the motion platform that combines reaction mass and active vibration isolation provided by the present invention; Figure 2 for Figure 1 A three-dimensional view of the motion platform where the reaction mass and active vibration isolation work together from another angle; Figure 3 for Figure 1 A three-dimensional view of the relevant structures on the gantry in the motion platform where the reaction mass and active vibration isolation work together; Figure 4 for Figure 3 Side view of the relevant structures on the gantry shown; Figure 5 for Figure 1 A three-dimensional view of the relevant structures on the main body of the platform in the motion platform where the reaction mass and active vibration isolation work together; Figure 6 for Figure 5 The main view of the relevant structures on the platform body shown.

[0019] The diagram labels are: 10. Fixed base; 11. Support leg; 20. Platform body; 21. Support surface; 22. Boss; 23. Vibration isolation unit; 30. Supporting platform; 31. Second Y-axis guide rail; 32. Second Y-axis slider; 33. Second Y-axis mounting plate; 34. Supporting plate; 40. Gantry frame; 41. Column; 42. Horizontal beam; 50. X-axis main motion assembly; 51. First X-axis guide rail; 52. First X-axis slider; 53. First X-axis mounting plate; 54. X-axis linear motor drive unit; 60. X-axis reaction mass assembly; 70. Z-axis actuator assembly; 71. Second X-axis guide rail; 72. Second X-axis slider; 73. Second X-axis mounting plate; 74. Z-axis direct drive motor; 80. Y-axis main motion assembly; 81. First Y-axis guide rail; 82. First Y-axis slider; 83. First Y-axis mounting plate; 84. Y-axis linear motor drive unit; 90. Y-axis reaction mass assembly; 101. First sensor; 102. Second sensor; 103. Third sensor; 104. Fourth sensor. Detailed Implementation

[0020] To make the objectives, technical solutions, and beneficial effects of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described in this specification are merely for explaining the invention and are not intended to limit the invention.

[0021] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0022] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0023] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0024] In an embodiment of the present invention, a motion platform that combines reaction mass and active vibration isolation is provided to reduce the inertial reaction force and reaction torque transmitted to the fixed base during high-speed acceleration and deceleration while ensuring that the load-bearing platform and the actuator run according to a predetermined trajectory, thereby improving the positioning accuracy, trajectory accuracy, stabilization time and long-term repeatability of the equipment.

[0025] It should be noted that in the description of this invention, the X-axis and Y-axis are a pair of orthogonal axes on a horizontal plane, and the Z-axis is a vertical axis. It should also be noted that the naming of the X-axis, Y-axis, and Z-axis is only used to distinguish three mutually orthogonal directions of motion and does not constitute a limitation on the scope of protection of this invention.

[0026] like Figures 1-2 As shown, the motion platform that coordinates reaction mass and active vibration isolation includes a fixed base 10, a platform body 20, a load-bearing platform 30, a gantry frame 40, an X-axis main motion assembly 50, an X-axis reaction mass assembly 60, a pair of Y-axis main motion assemblies 80, a pair of Y-axis reaction mass assemblies 90, and a sensor group.

[0027] The fixed base 10 serves as the mounting foundation for the entire motion platform. Its bottom is equipped with multiple height-adjustable support feet 11 for leveling and height compensation on the ground or equipment mounting base. In some embodiments, the support feet 11 may employ a threaded adjustment structure, where the extension length of the support foot 11 is changed by rotating the adjusting nut, thereby adjusting the levelness of the fixed base 10. It is understood that the specific structural form of the support feet 11 is not limited to threaded adjustment; those skilled in the art can select air-floating support feet, hydraulic support feet, or other support structures with height adjustment functions according to actual installation requirements.

[0028] The platform body 20 is supported on the fixed base 10 by a plurality of vibration isolation units 23. The vibration isolation units are disposed between the platform body 20 and the fixed base 10 to support the platform body 20 and to attenuate and isolate vibrations transmitted to the platform body 20. In this embodiment, the vibration isolation units 23 are elastic damping components, which can be made of materials with elastic and damping properties such as polyurethane (urethane rubber), air springs, and dampers. Multiple vibration isolation units 23 are distributed at different positions on the bottom of the platform body 20 to provide stable support for the platform body 20 and reduce the transmission of vibrations between the fixed base 10 and the platform body 20. It is understood that the specific type, quantity, and arrangement of the vibration isolation units 23 can be selected and optimized according to the size, weight distribution, and vibration isolation performance requirements of the platform body 20, and can be configured according to actual needs by those skilled in the art.

[0029] Combination Figure 5 and Figure 6 As shown, the platform body 20 includes a support surface 21 and a boss 22 extending upward from a predetermined portion of the support surface 21. The support surface 21 provides an installation reference surface for components such as the gantry 40 and the Y-axis reaction mass assembly 90. The boss 22 protrudes upward from the central region of the support surface 21, providing an installation and guiding foundation for the Y-axis main motion assembly 80 and the load-bearing platform 30. In this embodiment, the boss 22 is cuboid in shape, and its two sides form a space between itself and the support surface 21 for the installation of the Y-axis reaction mass assembly 90. It is understood that the specific shape and size of the boss 22 can be designed according to the Y-axis travel and installation space requirements, and is not limited to a cuboid shape.

[0030] The gantry frame 40 is fixed to the platform body 20 and is used to support the X-axis main motion assembly 50 and the Z-axis execution assembly 70. Specifically, the gantry frame 40 includes a pair of parallel and spaced columns 41 and a crossbeam 42 mounted on top of the pair of columns 41. The bottoms of the pair of columns 41 are vertically fixed to the support surface 21 and are located on both sides of the boss 22, so that the crossbeam 42 is located above the boss 22. Thus, the crossbeam 42 forms a bridge-like structure above the boss 22, spanning the movement area of ​​the bearing platform 30, providing support and guidance for movement in the X-axis direction.

[0031] Combination Figure 3 and Figure 4 As shown, the X-axis main motion assembly 50 is slidably connected to the top of the gantry 40 and is used to drive the Z-axis actuator 70 to slide along the X-axis. Specifically, the X-axis main motion assembly 50 includes a first X-axis guide rail 51 fixed to the gantry 40, a first X-axis slider 52 slidably held on the first X-axis guide rail 51, a first X-axis mounting plate 53 fixed to the first X-axis slider 52, and an X-axis linear motor drive unit 54 fixed to the first X-axis mounting plate 53. The first X-axis guide rail 51 is arranged on one side of the crossbeam 42 along the X-axis direction, and the first X-axis slider 52 slides in cooperation with the first X-axis guide rail 51, allowing the first X-axis mounting plate 53 to reciprocate along the X-axis direction. The X-axis linear motor drive unit 54 is fixed to the first X-axis mounting plate 53 and is used to drive the Z-axis actuator 70 to move along the X-axis direction.

[0032] In this embodiment, the X-axis linear motor drive unit 54 is a U-shaped coreless linear motor, composed of two linear motors joined together, one for driving and the other for shock absorption. The U-shaped coreless linear motor features no cogging effect, good motion smoothness, and small thrust fluctuation, making it suitable for high-precision positioning applications. It is understood that the specific type and number of the X-axis linear motor drive unit 54 are not limited to this; those skilled in the art can select other types of linear motors, such as coreless linear motors or flat linear motors, according to thrust requirements, stroke length, and accuracy requirements.

[0033] Furthermore, the X-axis reaction mass assembly 60 is fixed to the top of the gantry 40 and is used to drive the X-axis main motion assembly 50 to slide along the X-axis to counteract the inertial reaction force (i.e., reaction force and reaction torque) generated during the acceleration and deceleration of the X-axis main motion assembly 50. In this embodiment, the X-axis reaction mass assembly 60 is also a U-shaped coreless linear motor, and is composed of two linear motors spliced ​​together. The stator of the X-axis reaction mass assembly 60 is fixed to the crossbeam 42, and the mover is connected to the first X-axis mounting plate 53. When the X-axis main motion assembly 50 accelerates and decelerates, the mover of the X-axis reaction mass assembly 60 acts as a reaction mass, absorbing the inertial reaction force generated by the X-axis main motion assembly 50 through controlled reverse motion, thereby reducing the vibration excitation transmitted to the gantry 40 and the platform body 20. It should be noted that the X-axis reaction mass assembly 60 can not only absorb the translational reaction force in the X-axis direction, but also generate a corresponding reaction torque to compensate for the X-axis acceleration and deceleration process when its installation position is offset from the center of mass of the X-axis main motion assembly 50 in the Z-axis direction, thereby suppressing the pitch vibration of the platform body 20.

[0034] In one embodiment, the Z-axis actuator 70 is slidably connected to the gantry 40 and includes a second X-axis guide rail 71 fixed to the gantry 40, a second X-axis slider 72 slidably held on the second X-axis guide rail 71, a second X-axis mounting plate 73 fixed to the second X-axis slider 72, and a Z-axis direct drive motor 74 fixed to the second X-axis mounting plate 73. The second X-axis guide rail 71 and the first X-axis guide rail 51 are arranged parallel to the X-axis and are respectively located on adjacent vertical sides of the crossbeam 42. The second X-axis mounting plate 73 slides along the X-axis direction through the second X-axis slider 72 and the second X-axis guide rail 71. The X-axis linear motor drive unit 54 is connected to the second X-axis mounting plate 73, enabling the X-axis linear motor drive unit 54 to drive the second X-axis mounting plate 73 to move along the X-axis.

[0035] The Z-axis direct drive motor 74 is fixed to the second X-axis mounting plate 73 and is used to drive the preset execution component to move up and down along the Z-axis. The preset execution component can be a mechanism that performs processing, inspection, or other actions on the workpiece placed on the support plate 34, such as a laser processing head, an optical inspection lens, or an exposure objective lens; it can also be a counterweight used to balance and adjust the mass distribution of the motion system. It is understood that the specific type and function of the preset execution component can be selected according to the actual application scenario.

[0036] Combination Figure 5 and Figure 6 As shown, a pair of Y-axis main motion components 80 are slidably connected to the platform body 20 and located on both sides of the support platform 30, respectively, for jointly driving the support platform 30 to slide along the Y-axis. Specifically, each Y-axis main motion component 80 includes a first Y-axis guide rail 81 fixed to the boss 22, a first Y-axis slider 82 slidably held on the first Y-axis guide rail 81, a first Y-axis mounting plate 83 fixed to the first Y-axis slider 82, and a Y-axis linear motor drive unit 84 fixed to the first Y-axis mounting plate 83. The first Y-axis guide rail 81 is arranged on the side of the boss 22 along the Y-axis direction, and the first Y-axis slider 82 slides in cooperation with the first Y-axis guide rail 81, allowing the first Y-axis mounting plate 83 to slide back and forth along the Y-axis direction. The Y-axis linear motor drive unit 84 is fixed to the first Y-axis mounting plate 83 and is used to drive the support platform 30 to move along the Y-axis direction.

[0037] In this embodiment, the Y-axis linear motor drive unit 84 is a U-shaped coreless linear motor, composed of two linear motors joined together, one for driving and the other for impact mitigation. It is understood that a pair of Y-axis main motion components 80 are respectively disposed on both sides of the boss 22, forming a dual-side dual-drive structure. This dual-side dual-drive structure provides a more balanced distribution of driving force to the support platform 30, reduces the lateral torque generated on the guide structure during driving, and improves the directional stability of the Y-axis motion.

[0038] A pair of Y-axis reaction mass assemblies 90 are fixed to the platform body 20, and are used to drive a corresponding Y-axis main motion assembly 80 to slide along the Y-axis to counteract the inertial reaction force (i.e., reaction force and reaction torque) generated when the Y-axis main motion assembly 80 accelerates or decelerates. Specifically, the Y-axis reaction mass assemblies 90 are fixed on the support surface 21, located in the space between the two sides of the boss 22 and the column 41 of the gantry 40. The mover of each Y-axis reaction mass assembly 90 is connected to the corresponding first Y-axis mounting plate 83. When the Y-axis main motion assembly 80 accelerates or decelerates, the mover of the Y-axis reaction mass assembly 90 acts as a reaction mass, absorbing the inertial reaction force generated by the Y-axis main motion assembly 80 through controlled reverse motion.

[0039] In this embodiment, the Y-axis reaction mass assembly 90 is a U-shaped coreless linear motor, and is composed of two linear motors spliced ​​together. It should be noted that since each pair of Y-axis reaction mass assemblies 90 independently drives its corresponding Y-axis main motion assembly 80, when there are differences in the acceleration and deceleration dynamics of the two Y-axis main motion assemblies 80, the two Y-axis reaction mass assemblies 90 can independently compensate for the reaction of their respective main motion assemblies, thereby structurally possessing the ability to suppress yaw angle sway of the bearing platform 30.

[0040] In this embodiment, the support platform 30 is slidably connected to the platform body 20 and is used to support the workpiece to be processed or inspected. Specifically, the support platform 30 includes a second Y-axis guide rail 31 fixed to the boss 22, a second Y-axis slider 32 slidably held on the second Y-axis guide rail 31, a second Y-axis mounting plate 33 fixed to the second Y-axis slider 32, and a support plate 34 fixed to the second Y-axis mounting plate 33. The second Y-axis guide rail 31 is arranged along the Y-axis direction on the upper surface of the boss 22, and the second Y-axis slider 32 is slidably engaged with the second Y-axis guide rail 31, so that the second Y-axis mounting plate 33 and the support plate 34 can slide back and forth along the Y-axis direction. The Y-axis linear motor drive unit 84 is used to drive the second Y-axis mounting plate 33 to move, thereby driving the support plate 34 to move along the Y-axis. The preset execution component driven by the Z-axis direct drive motor 74 can perform processing or inspection operations on the workpiece to be processed or inspected placed on the support plate 34.

[0041] It should be noted that in this embodiment, the support platform 30 is disposed on the top of the boss 22, and a pair of Y-axis main motion components 80 are respectively disposed on both sides of the boss 22. The Y-axis linear motor drive unit 84 transmits the driving force to the second Y-axis mounting plate 33 through the intermediate connection structure, thereby driving the support plate 34 to move.

[0042] In this embodiment, the sensor group is used to monitor the positions of the Z-axis actuator 70, the X-axis main motion assembly 50, the support platform 30, and the Y-axis main motion assembly 80.

[0043] Specifically, the sensor group includes a first sensor 101, a second sensor 102, a third sensor 103, and a fourth sensor 104. In this embodiment, the first sensor 101, the second sensor 102, the third sensor 103, and the fourth sensor 104 are all grating rulers. The grating ruler consists of a scale grating and a reading head. The scale grating is fixed to a stationary component, and the reading head is fixed to a moving component. The position of the moving component is measured by the movement of the reading head relative to the scale grating.

[0044] The first sensor 101 has its scale grating arranged along the X-axis on the gantry 40, and its reading head is mounted on the first X-axis mounting plate 53. The first sensor 101 measures the actual position of the X-axis main motion assembly 50 along the X-axis, i.e., the position of the first X-axis mounting plate 53 relative to the gantry 40. The second sensor 102 has its scale grating arranged along the X-axis on the gantry 40, and its reading head is mounted on the second X-axis mounting plate 73. The second sensor 102 measures the actual position of the Z-axis actuator 70 along the X-axis, i.e., the position of the second X-axis mounting plate 73 relative to the gantry 40. Through the cooperation of the first sensor 101 and the second sensor 102, the position tracking relationship between the X-axis linear motor drive unit 54 and the second X-axis mounting plate 73 can be obtained, providing feedback information for position synchronization control in the X-axis direction.

[0045] The scale grating of the third sensor 103 is arranged along the Y-axis on the side of the boss 22, and its reading head is mounted on the first Y-axis mounting plate 83. The third sensor 103 is used to measure the actual position of the Y-axis main motion assembly 80 along the Y-axis direction. The scale grating of the fourth sensor 104 is arranged along the Y-axis on the boss 22, and its reading head is mounted on the second Y-axis mounting plate 33. The fourth sensor 104 is used to measure the actual position of the support platform 30 along the Y-axis direction.

[0046] In this embodiment, three fourth sensors 104 are distributed at intervals along the X-axis at the bottom of the support plate 34. The three fourth sensors 104 are respectively positioned at different locations along the X-axis at the bottom of the support plate 34, enabling simultaneous detection of the position information of the support plate 34 along the Y-axis. The fourth sensor 104 located in the middle position measures the average position of the support plate 34 along the Y-axis, while the two fourth sensors 104 located on either side can detect whether the support platform 30 has experienced a yaw angle deflection around the Z-axis by comparing the differences in their respective measurements. In other words, the configuration of the three fourth sensors 104 is mainly used to detect whether the driving of the two Y-axis main motion components 80 has deviated. When the driving of the two Y-axis main motion components 80 is completely synchronized, the measurement values ​​of the three fourth sensors 104 should be consistent (considering the ideal rigidity of the support plate 34); when the driving of the two Y-axis main motion components 80 is asynchronous, the support plate 34 will experience a yaw angle deflection, at which point the measurement values ​​of the three fourth sensors 104 will differ, and the yaw angle deviation information can be obtained by comparing this difference. It should be noted that the number of fourth sensors 104 is not limited to three. Those skilled in the art can select an appropriate number of sensors, such as two, four or more, according to the size, rigidity and measurement accuracy requirements of the support plate 34.

[0047] The working principle of the motion platform with reaction mass and active vibration isolation synergy provided by the present invention will be explained below in conjunction with the above structure.

[0048] When the support platform 30 accelerates or decelerates along the Y-axis, the Y-axis linear motor drive unit 84 applies a driving force to the second Y-axis mounting plate 33, causing the support plate 34 and the workpiece it carries to accelerate or decelerate along the Y-axis. Simultaneously, according to the principle of action and reaction, the mover of the Y-axis linear motor drive unit 84 applies a reaction force in the opposite direction to the first Y-axis mounting plate 83. This reaction force is transmitted through the connecting structure to the mover of the Y-axis reaction mass assembly 90, causing the mover of the Y-axis reaction mass assembly 90 to move in the opposite direction. Since the stator of the Y-axis reaction mass assembly 90 is fixed to the support surface 21, its mover, as a reaction mass, counteracts the inertial reaction force generated by the acceleration and deceleration of the Y-axis main motion assembly 80 during movement, thereby reducing the vibration excitation level transmitted to the platform body 20 and the fixed base 10. When the drives of the two Y-axis main motion components 80 are out of sync, the three fourth sensors 104 can detect the yaw angle deflection information of the carrier plate 34, thereby providing feedback signals for subsequent synchronization error compensation.

[0049] Similarly, when the X-axis main motion assembly 50 accelerates or decelerates along the X-axis, the mover of the X-axis reaction mass assembly 60 acts as a reaction mass, absorbing the reaction force generated by the X-axis main motion assembly 50 through controlled reverse motion, thereby reducing the vibration excitation level transmitted to the gantry 40 and the platform body 20. Simultaneously, the platform body 20 achieves vibration isolation between itself and the fixed base 10 through vibration isolation units, further attenuating residual disturbances.

[0050] It is important to emphasize that the X-axis reaction mass assembly 60 and Y-axis reaction mass assembly 90 in this invention can not only absorb the translational reaction force of the main motion assembly in the corresponding direction, but also, when there is a height difference between the reaction mass assembly and the main motion assembly in the Z-axis direction, the reverse motion of the reaction mass assembly will generate a reverse torque on the platform body 20. This reverse torque can partially offset the pitching or rolling torque generated by the main motion assembly during acceleration and deceleration, thereby achieving synergistic vibration suppression at both the translational and rotational levels.

[0051] In some embodiments, the support surface 21 of the platform body 20 is further provided with a mounting groove or mounting boss for mounting the Y-axis reaction mass assembly 90, so as to facilitate the precise positioning and fixing of the Y-axis reaction mass assembly 90. It is understood that the specific mounting method of the Y-axis reaction mass assembly 90 can be selected according to the structural form and manufacturing process of the platform body 20.

[0052] In some embodiments, the uprights 41 and crossbeams 42 of the gantry 40, as well as the bottom of the uprights 41 and the support surface 21, can be fixedly connected by bolts, locating pins, or other means to ensure the rigidity and geometric accuracy of the gantry 40 relative to the platform body 20. It is understood that those skilled in the art can select specific connection methods according to actual needs.

[0053] In some embodiments, the stator of the X-axis reaction mass assembly 60 is fixed to the crossbeam 42 by a mounting bracket, and an adjusting shim is provided between the mounting bracket and the crossbeam 42 to adjust the installation position accuracy of the X-axis reaction mass assembly 60. Similarly, the stator of the Y-axis reaction mass assembly 90 is fixed to the support surface 21 by a mounting base, and an adjusting structure can also be provided between the mounting base and the support surface 21.

[0054] It should be noted that in this invention, the configuration of the X-axis linear motor drive unit 54, X-axis reaction mass assembly 60, Y-axis linear motor drive unit 84, and Y-axis reaction mass assembly 90 as U-shaped coreless linear motors is only one specific implementation of this embodiment. It is understood that those skilled in the art can select other types of linear motors, such as coreless linear motors, flat linear motors, and cylindrical linear motors, based on actual thrust requirements, installation space, and accuracy requirements. Different types of linear motors have their own characteristics in terms of thrust density, thrust fluctuation, heat dissipation performance, and installation methods; the specific selection should be based on meeting actual usage requirements.

[0055] This invention is not limited to the descriptions and embodiments herein; therefore, other advantages and modifications can be readily realized by those skilled in the art. Thus, without departing from the spirit and scope of the general concept defined by the claims and their equivalents, this invention is not limited to the specific details, representative devices, and illustrative examples shown and described herein. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A motion platform that combines reaction mass and active vibration isolation, characterized in that, include: Fixed base; The platform body is supported on the fixed base by a number of vibration isolation units; A support platform, which is slidably connected to the platform body; A gantry frame, which is fixed to the platform body and slidably connected to a Z-axis actuator; The X-axis main motion assembly is slidably connected to the top of the gantry frame and is used to drive the Z-axis actuator to slide along the X-axis; The X-axis reaction mass assembly is fixed to the top of the gantry frame and is used to drive the X-axis main motion assembly to slide along the X-axis to counteract the inertial reaction force generated when the X-axis main motion assembly accelerates or decelerates. A pair of Y-axis main motion components are slidably connected to the platform body and located on both sides of the bearing platform, respectively, for jointly driving the bearing platform to slide along the Y-axis; A pair of Y-axis reaction mass components, the Y-axis reaction mass components being fixed to the platform body, are used to drive a corresponding Y-axis main motion component to slide along the Y-axis, so as to counteract the inertial reaction force generated when the Y-axis main motion component accelerates or decelerates; A sensor array; the sensor array is used to monitor the positions of the Z-axis actuator, the X-axis main motion assembly, the support platform, and the Y-axis main motion assembly.

2. The motion platform combining reaction mass and active vibration isolation as described in claim 1, characterized in that, The platform body includes a support surface and a boss extending upward from a predetermined part of the support surface; the gantry includes a pair of parallel and spaced columns and a crossbeam mounted on the top of the pair of columns; the bottoms of the pair of columns are vertically fixed to the support surface and are respectively located on both sides of the boss, so that the crossbeam is located above the boss.

3. The motion platform combining reaction mass and active vibration isolation as described in claim 1, characterized in that, The X-axis main motion assembly includes a first X-axis guide rail fixed to the gantry, a first X-axis slider slidably held on the first X-axis guide rail, a first X-axis mounting plate fixed to the first X-axis slider, and an X-axis linear motor drive unit fixed to the first X-axis mounting plate; the X-axis reaction mass assembly is used to drive the first X-axis mounting plate to move.

4. The motion platform combining reaction mass and active vibration isolation as described in claim 3, characterized in that, The Z-axis actuation component includes a second X-axis guide rail fixed to the gantry, a second X-axis slider slidably held on the second X-axis guide rail, a second X-axis mounting plate fixed to the second X-axis slider, and a Z-axis direct drive motor fixed to the second X-axis mounting plate; the X-axis linear motor drive unit is used to drive the second X-axis mounting plate to move; the Z-axis direct drive motor is used to drive a preset actuation component to move up and down along the Z-axis; the second X-axis guide rail and the first X-axis guide rail are arranged parallel to the X-axis and are respectively located on adjacent vertical sides of the gantry.

5. The motion platform combining reaction mass and active vibration isolation as described in claim 4, characterized in that, The sensor group includes a first sensor and a second sensor; both the first sensor and the second sensor are grating rulers; the scale grating of the first sensor is arranged along the X-axis on the gantry, and its reading head is mounted on the first X-axis mounting plate; the scale grating of the second sensor is arranged along the X-axis on the gantry, and its reading head is mounted on the second X-axis mounting plate.

6. The motion platform combining reaction mass and active vibration isolation as described in claim 2, characterized in that, Each of the Y-axis main motion components includes a first Y-axis guide rail fixed to the boss, a first Y-axis slider slidably held on the first Y-axis guide rail, a first Y-axis mounting plate fixed to the first Y-axis slider, and a Y-axis linear motor drive unit fixed to the first Y-axis mounting plate; the Y-axis reaction mass component is fixed to the support surface and is used to drive the first Y-axis mounting plate to move.

7. The motion platform combining reaction mass and active vibration isolation as described in claim 6, characterized in that, The support platform includes a second Y-axis guide rail fixed to the boss, a second Y-axis slider slidably held on the second Y-axis guide rail, a second Y-axis mounting plate fixed on the second Y-axis slider, and a support plate fixed on the second Y-axis mounting plate; the Y-axis linear motor drive unit is used to drive the second Y-axis mounting plate to move; the Z-axis direct drive motor is used to drive the preset execution component to rise and fall along the Z-axis.

8. The motion platform combining reaction mass and active vibration isolation as described in claim 7, characterized in that, The sensor group includes a third sensor and a fourth sensor; both the third sensor and the fourth sensor are grating rulers; the scale grating of the third sensor is arranged along the Y-axis on the side of the boss, and its reading head is mounted on the first Y-axis mounting plate; the scale grating of the fourth sensor is arranged along the Y-axis on the boss, and its reading head is mounted on the second Y-axis mounting plate.

9. The motion platform combining reaction mass and active vibration isolation as described in claim 8, characterized in that, The fourth sensor consists of three sensors, which are spaced apart along the X-axis at the bottom of the support plate.

10. The motion platform combining reaction mass and active vibration isolation as described in claim 1, characterized in that, The bottom of the fixed base is provided with multiple height-adjustable support feet.

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