CN109079552B - Triaxial cutter servo device based on compliant parallel mechanism - Google Patents

Abstract

The invention relates to the technical field of nano positioning, measuring and processing devices, in particular to a triaxial cutter servo device based on a compliant parallel mechanism, which comprises an outer side fixed base, an inner side fixed base, a uniaxial nano positioning platform and a triaxial end effector, wherein the uniaxial nano positioning platform and the triaxial end effector transmit motion through a compliant hinge and a flexible rod piece; the triaxial end effector is provided with a capacitance sensor, and the capacitance sensor is connected with a controller; the output of controller is connected with piezoceramics driver, piezoceramics driver connects in unipolar nanometer positioning platform's input, triaxial end effector connects in three unipolar nanometer positioning platform's output. The invention can realize the output of the nanometer linear displacement of the triaxial end effector, simultaneously directly measure the output displacement of the end by the sensor and carry out feedback control, and has the advantages of high rigidity, high precision, high bandwidth, large stroke, high speed, high acceleration, large bearing capacity and excellent decoupling performance.

Description

A three-axis tool servo device based on a compliant parallel mechanism

technical field

The invention relates to the technical field of nano-positioning, measuring and processing devices, and more particularly, to a three-axis tool servo device based on a compliant parallel mechanism.

Background technique

The compliance mechanism is one of the main means of forming the body of the nano-positioning, measuring and processing device. It is a key part of micro-nano operation, micro-nano measurement, and micro-nano processing/manufacturing. plays an important role in related fields.

The compliant hinge utilizes the characteristics of easy deformation of the weak part of the structure and the reversible elastic deformation characteristics of the material itself to achieve the required kinematic pair function, and has the advantages of free assembly, zero clearance, no friction and no lubrication. The compliant mechanism replaces the kinematic pair of each moving branch of the mechanism with a compliant hinge, and uses a flexible link to connect each compliant hinge to form a corresponding flexible branch, and connects the moving platform and the fixed base through the compliant hinge to form a corresponding institution. The compliant mechanism designed by the rigid body replacement method can achieve the required motion and function, but in some fields with higher precision requirements, the compliant parallel mechanism requires higher stiffness and better motion characteristics. The structure is difficult to meet the requirements of high precision, high stiffness, low coupling/full decoupling, large bearing capacity, high speed/acceleration, etc.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the deficiencies of the prior art and provide a three-axis tool servo device based on a compliant parallel mechanism, which can meet the requirements of high rigidity, large stroke, high bandwidth, high precision and high accuracy in nano-positioning, measurement and processing occasions. , low coupling/full decoupling, high stability and large load performance requirements.

In order to solve the above-mentioned technical problems, the technical scheme adopted in the present invention is:

The invention provides a three-axis tool servo device based on a compliant parallel mechanism, comprising an outer fixed base, an inner fixed base, a single-axis nano-positioning platform that transmits motion through a first motion branch, and a second motion branch to guide and Decoupled three-axis end effector, three sets of outer fixed bases, inner fixed bases, and uniaxial nanopositioning platforms are orthogonal to each other, and are located in the XOY plane, XOZ plane and YOZ plane respectively; the uniaxial nanopositioning platform Set between the outer fixed base and the inner fixed base, the single-axis nano-positioning platform is connected to the three-axis end effector; The force/displacement/motion generated by the ceramic drive is transmitted to the motion branches of the three-axis end effector, and the three motion branches are connected in parallel and are orthogonal to each other; the three-axis end effector is connected with a tool; the three-axis end effector The actuator is provided with a capacitive sensor for measuring the displacement of the tool on three orthogonal linear axes X/Y/Z in space, the capacitive sensor is connected with a controller; the output end of the controller is connected with a piezoelectric ceramic driver, The piezoelectric ceramic driver is connected to the input end of the single-axis nano-positioning platform, and the three-axis end effector is connected to the output ends of the three single-axis nano-positioning platforms.

In the three-axis tool servo device based on the compliant parallel mechanism of the present invention, three single-axis nano-positioning platforms are connected in parallel to form a three-axis tool servo device. The algorithm is designed to obtain the real-time driving voltage of three piezoelectric ceramic drivers, and through the three motion branches, the feed amount of the three-axis end effector on different linear axes is controlled in real time, and the tool is driven to realize three-axis nano-machining. The invention uses three parallel and orthogonal motion branches to realize the output of the nano-level linear displacement of the three-axis end effector; at the same time, the output displacement of the end is directly measured and feedback controlled by the capacitive sensor, and has high rigidity, high precision and high bandwidth. , large stroke, high speed, high acceleration, high bearing capacity and excellent decoupling performance, it has outstanding advantages in applications such as ultra-precision machining, and is also suitable for applications such as micro-nano operation, micro-nano measurement and micro-nano processing/manufacturing , which can not only be integrated into ultra-precision machining machines, but also can be installed in many types of precision equipment/instruments/equipment as stand-alone machining, measurement or motion platforms/components/units.

Further, the first moving branch includes an input end-guided compliant hinge, an input end, a first-level lever input point rotary compliant hinge, a first-level lever fulcrum rotary compliant hinge, and a first-level lever active rod. , a first-level lever output point rotary compliant hinge, a first-level lever driven rod and a first connecting end; one end of the piezoelectric ceramic driver is connected to the uniaxial nano-positioning platform through a top wire, and the piezoelectric ceramic driver is not connected to the input end. Gap connection, the first connection end is connected with the triaxial end effector. Through the optimized design of structural parameters such as flexible hinges and flexible rods, the preference requirements for multiple performance indicators in different applications can be met.

Further, the secondary lever input point rotary compliant hinge, the secondary lever fulcrum rotary compliant hinge, and the secondary lever active rod are also arranged in sequence between the primary lever driven rod and the first connection end. , The secondary lever output point rotary compliant hinge, the secondary lever driven rod and the secondary lever driven rod output end guide compliant hinge. The two-stage lever-type micro-displacement amplifying mechanism can realize a large-scale displacement output. The first connecting end of the first moving branch is connected with the three-axis end effector.

Further, the second movement branch includes a second connecting end, a connecting rod, an input point compliant hinge and a decoupling guide compliant hinge provided on the end effector, the second connecting end, the connecting rod, and the input point compliant hinge. And the decoupling guide compliant hinge connects the second connection end and the first connection end in series in sequence. The first kinematic branch and the second kinematic branch on the single-axis nanopositioning platform and the end effector are connected to form three kinematic branches. Axis decoupling, easy to design multi-axis linkage controller.

Further, the end face of the top wire is provided with balls in contact, the balls are in point contact with a force sensor for measuring preload force, and a preload block is provided between the force sensor and the piezoelectric ceramic driver; the The force sensor is connected to the controller. When installing the single-axis nanopositioning platform, after placing the piezoelectric ceramic driver in the chute, the top screw, ball, force sensor and preload block are used to ensure the gap-free connection between the piezoelectric ceramic driver and the input end; the ball is used to achieve The surface contact or point contact during the preloading process is easy to determine the action point and direction of the preloading force, ensuring the preloading accuracy, avoiding the lateral force and bending moment during the preloading process, and eliminating the torque and Lateral forces, protecting torque-limited actuators such as piezo actuators. When the present invention is applied, the axes of the rotary compliant hinge of the top screw, ball, force sensor, preload block, piezoelectric ceramic driver, input end, and input point of the first-level lever are coincident, and the top screw, ball, force sensor and preload are used. block to ensure a gap-free connection of the piezo driver to the input.

Further, the top of the preload block is reserved with mounting holes for mounting the measuring block and the reflector bracket. Install the measuring block, which is convenient for the capacitive sensor to measure the measuring surface of the measuring block. You can also install the reflector bracket, use the laser interferometer to measure, calibrate or calibrate the capacitive sensor, and monitor the rotation of the preload block to measure the linear displacement of the capacitive sensor. The effect of precision.

Further, the outer fixing base includes a first outer fixing base located on the XOZ plane and the YOZ plane and a second outer fixing base located on the XOY plane, two groups of first outer fixing bases are vertically connected, and the second outer fixing base is vertically connected. The adjacent two sides of the outer fixing base are respectively vertically connected with the first outer fixing base. The three-axis tool servo device set in this way has a compact structure, occupies a small volume, and is light to use.

Further, the first outer fixed base is provided with a first connection hole for connecting with the uniaxial nanopositioning platform, a first sink for avoiding motion interference with each component on the motion branch to which the uniaxial nanopositioning platform belongs. a groove, a first heat dissipation grid for dissipating the heat generated by the piezoelectric ceramic driver, and two sets of orthogonally distributed capacitive sensor brackets, the first heat dissipation grid is arranged through the first outer base, and the first sink is arranged in the the inner side of the first outer fixing base; the capacitive sensor bracket is arranged protruding from the first outer fixing base, and is connected with the capacitive sensor. The first outer fixing bases are located on the XOZ plane and the YOZ plane respectively, and are respectively connected with the uniaxial nanopositioning platform through several screws and pins; the first sink corresponds to the multiple groups of rods and compliant rods that transmit force and displacement on the uniaxial nanopositioning platform. The hinge is used to dissipate heat through the first heat dissipation grid to ensure the stability of the piezoelectric ceramic driver under high power conditions; the lower part of the capacitive sensor bracket is connected to the first outer fixing base for fixing the capacitive sensor. In order to strengthen the capacitive sensor The stiffness of the bracket can be provided with several reinforcing ribs.

Further, the second outer fixed base is provided with a second connection hole for connecting with the three-axis nano-positioning platform, a second sink for avoiding movement interference with each component on the motion branch to which the single-axis nano-positioning platform belongs. a groove and a second heat dissipation grid for dissipating heat generated by the piezoelectric ceramic driver, the second heat dissipation grid is disposed through the second outer base, and the second sink groove is disposed on the inner side of the second outer fixed base. The second outer fixing base is located on the XOY plane and is connected to the uniaxial nanopositioning platform through several screws and pins respectively; A heat dissipation grid and a second heat dissipation grid conduct heat dissipation to ensure the stability of the piezoelectric ceramic driver under high power conditions.

Further, three-way reinforcing ribs are provided at the joints of the three groups of inner fixing bases; The wires and the sensor signal wires are arranged through the third heat dissipation grid. Between the uniaxial nanopositioning platforms, the uniaxial nanopositioning platform and the first outer fixing base, the uniaxial nanopositioning platform and the second outer fixing base, the uniaxial nanopositioning platform and the inner fixing base, the inner fixing base A number of spacers, screws and pins are used to fasten the seat and the three-way reinforcing ribs together, so that the fixed part of the uniaxial nanopositioning platform and the bracket of the capacitive sensor are fixed relative to the first outer fixing base and the second outer fixing base. There is no relative displacement of the base, the inner fixed base, and the three-way reinforcing rib.

Compared with the prior art, the beneficial effects of the present invention are:

(1) The present invention uses three parallel motion branches to realize the displacement output of the three-axis end effector, and has high stiffness, high precision, high speed, high acceleration and large bearing capacity, so that the three-axis end effector can be It has outstanding advantages in applications such as precision machining;

(2) The present invention uses compliant hinges and flexible rods to transmit nano-scale motion, and can obtain excellent decoupling, bandwidth, stiffness, working space, etc.;

(3) The output displacement of the three-axis end effector of the present invention can be directly measured, which is convenient for full-closed-loop real-time feedback control; the possible coupling or error is detected by the capacitive sensor to improve the accuracy and stability of nano-positioning;

(4) The single-axis nano-positioning platform of the present invention uses a two-stage lever-type micro-displacement amplifying mechanism, which effectively expands the output displacement range of the piezoelectric-driven compliance mechanism and realizes nano-level processing in a wider range. In actual use, the displacement gain coefficient can also be designed according to the requirements, and the optimal design of the compliant hinge and flexible rod can be used to meet the preference characteristics of multiple performance index parameters in specific application scenarios;

(5) The outer and inner fixed bases of the present invention are provided with heat dissipation grid holes corresponding to the piezoelectric ceramic driver, which can realize high-power displacement output; there are also sink grooves for each moving rod and compliant hinge, High-power displacement transfer can be achieved; thereby improving the stability of the device under high-bandwidth and high-power conditions;

(6) The three uniaxial nanopositioning platforms of the present invention are connected in pairs, and each uniaxial nanopositioning platform is respectively connected with the outer fixing base and the inner fixing base, and the three inner fixing bases are connected by three-way reinforcing ribs. Fastening, the entire device fixing base has sufficient rigidity;

(7) The single-axis nano-positioning platform of the present invention uses balls to realize surface contact or point contact during the preloading process, which is easy to determine the action point and direction of the preloading force, ensures the preloading accuracy, and avoids the occurrence of sideways during the preloading process. force and bending moment, while eliminating the torque and lateral force generated by the rotation of the top wire, and protecting the piezoelectric ceramic driver with limited torque.

Description of drawings

FIG. 1 is a positive three-axis view of the three-axis tool servo device based on the compliant parallel mechanism of the present invention.

FIG. 2 is a positive triaxial view of the uniaxial nanopositioning platform in FIG. 1 .

FIG. 3 is a positive triaxial view of the three-axis end effector in FIG. 1 .

FIG. 4 is a normal triaxial view of the first outer fixing base in FIG. 1 .

FIG. 5 is an isometric view of the second outer fixing base in FIG. 1 .

FIG. 6 is an isometric view of the inner fixed base in FIG. 1 .

FIG. 7 is a normal triaxial view of the three-direction reinforcing rib in FIG. 1 .

In the drawings: 1-piezoelectric ceramic driver; 2-uniaxial nano-positioning platform; 21-top wire; 22-ball; 23-preload block; 24-input end guide compliant hinge; 25-input end; 26-a Level 1 lever input point rotary compliant hinge; 27- level 1 lever fulcrum rotary compliant hinge; 28- level lever active rod; 29- level lever output point rotary compliant hinge; 210- level one lever driven rod; 211 - Rotary compliant hinge at the input point of the secondary lever; 212 - Rotary compliant hinge at the fulcrum of the secondary lever; 213 - Active lever of the secondary lever; 214 - Rotary compliant hinge at the output point of the secondary lever; 215 - Secondary lever from Moving rod; 216- secondary lever follower rod output end guide compliant hinge; 217- first connecting end; 3- three-axis end effector; 311- Z-direction second connecting end; 312-Z-direction connecting rod; 313- Z direction input point compliant hinge; 314-Z-Y decoupling guide compliant hinge; 315-Z-X decoupling guide compliant hinge; 321-Y second connecting end; 322-Y connecting rod; 323-Y input point compliant hinge; 324-Y-Z decoupling guide compliant hinge; 325-Y-X decoupling guide compliant hinge; 331-X to the second connecting end; 332-X to the connecting rod; 333-X to the input point compliant hinge; 334-X-Z decoupling guide compliant Hinge; 335-X-Y Decoupling Guided Compliant Hinge; 34-Tool Fixed End and Measurement Reference Surface; 4-Diamond Tool; 5-Capacitance Sensor; 6-First Outer Fixed Base; 61-First Connection Hole; a heat dissipation grid; 63-first sink; 64-capacitance sensor bracket; 7-second outer fixing base; 71-second connection hole; 72-second heat dissipation grid; 73-second sink; 8-inside Fixed base; 81-first screw hole; 82-third heat grid; 83-first pin hole; 84-third sink; 9-three-way reinforcing rib; 91-second screw hole; 92-second pin hole.

Detailed ways

The present invention will be further described below in conjunction with specific embodiments. Among them, the accompanying drawings are only used for exemplary description, and they are only schematic diagrams, not physical drawings, and should not be construed as restrictions on this patent; in order to better illustrate the embodiments of the present invention, some parts of the accompanying drawings will be omitted, The enlargement or reduction does not represent the size of the actual product; it is understandable to those skilled in the art that some well-known structures and their descriptions in the accompanying drawings may be omitted.

The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar components; in the description of the present invention, it should be understood that if there are terms “upper”, “lower”, “left” and “right” The orientation or positional relationship indicated by etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the indicated device or element must have a specific orientation, with a specific orientation. Orientation structure and operation, so the terms describing the positional relationship in the accompanying drawings are only used for exemplary illustration, and should not be construed as a limitation on the present patent. Those of ordinary skill in the art can understand the specific meanings of the above terms according to specific situations.

Example 1

1 to 7 are embodiments of the three-axis tool servo device based on a compliant parallel mechanism of the present invention, including an outer fixed base, an inner fixed base 8, and a uniaxial nanometer that transmits motion through a first motion branch. The positioning platform 2 and the three-axis end effector 3 guided and decoupled by the second motion branch chain, three sets of outer fixed bases, inner fixed bases 8, and uniaxial nanopositioning platforms 2 are orthogonal in two and two, respectively located in XOY The plane, the XOZ plane and the YOZ plane, the uniaxial nanopositioning platform 2 is arranged between the outer fixed base and the inner fixed base 8, and the uniaxial nanopositioning platform 2 is connected with the three-axis end effector 3; the first motion branch and The second kinematic branches all include a variety of compliant hinges and flexible rods. The first kinematic branch and the second kinematic branch are connected to form three kinematic branches, which transmit the force/displacement/motion generated by the piezoelectric ceramic driver 1 to the three kinematic branches. Axial end effector 3, three motion branches are connected in parallel and orthogonal to each other; three-axis end effector 3 can be connected to different types of diamond tools 4, including multiple sets of compliant hinges and flexible rods for guiding and decoupling The formed second motion branch is provided with a measuring surface for displacement closed-loop feedback detection; the diamond tool 4 is fastened inside the three-axis end effector 3 through several screws; the three-axis end effector 3 is provided with a measuring surface for measuring the A capacitive sensor 5 for displacement on three orthogonal linear axes X/Y/Z in space, the capacitive sensor 5 is connected to a controller; the output end of the controller is connected to a piezoelectric ceramic driver 1, and the piezoelectric ceramic driver 1 is connected to a single axis The input end of the nanopositioning platform 2 and the three-axis end effector 3 are connected to the output ends of the three single-axis nanopositioning platforms 2 .

In the implementation of this embodiment, the output displacement of the three linear axes of the diamond tool 4 is directly detected by the capacitive sensor 5, the detected data is fed back to the controller, and the input terminal voltage data is calculated by the preset algorithm, and sent to the piezoelectric ceramic driver In 1, through three motion branches, the feed of the three-axis end effector 3 on different linear axes is controlled in real time, and the tool 4 is driven to realize three-axis nano-processing; the setting of the compliant hinge can realize high-power motion transmission.

As shown in Figure 2, the uniaxial nanopositioning platform 2 is provided with a top wire 21, a ball 22 (covered in the figure), a preload block 23, an input end guide compliant hinge 24, an input end 25, a first-level lever input point rotary type Compliant hinge 26, first-level lever fulcrum rotating flexible hinge 27, first-level lever active rod 28, first-level lever output point rotating flexible hinge 29, first-level lever driven rod 210, second-level lever input point rotating flexible hinge 211. Rotating compliant hinge at secondary lever fulcrum 212, secondary lever active rod 213, secondary lever output point rotary compliant hinge 214, secondary lever driven rod 215, secondary lever driven rod output guide compliant hinge 216. The first connection end 217, one end of the piezoelectric ceramic driver 1 is connected to the fixed part of the uniaxial nanopositioning platform 2 through the top wire 21, and several rods and compliant hinges are sequentially arranged in series on the input end 25 and the first connection end Between 217, the input end 25 is connected to the piezoelectric ceramic driver 1 without a gap. Among them, the end face of the jack screw 21 is provided with balls 22, and the balls 22 are in point contact with a force sensor (not shown in the figure, which can be omitted in actual use) for measuring the pre-tightening force. The force sensor and the piezoelectric ceramic driver 1 There is a preload block 23 between them, and the force sensor is connected with a controller; the ball 22 is used in the preload device to realize the surface contact or point contact during the preload process, which is easy to determine the action point and direction of the preload force to ensure the preload force. The tightening accuracy can be avoided, and the lateral force and bending moment generated during the preloading process can be avoided. At the same time, the torque and lateral force generated by the rotation of the top wire 21 can be eliminated, so as to protect the piezoelectric ceramic driver 1 and other drivers with limited torque. The axes of the jacking wire 21, the ball 22, the force sensor, the preloading block 23, the piezoelectric ceramic driver 1, the input end 25, the first-level lever input point rotary compliant hinge 26 are coincident, and the jacking wire 21, the ball 22, the force sensor and the A preload block 23 ensures a gap-free connection between the piezoelectric ceramic driver 1 and the input terminal 25 . The compliant hinge includes a series-connected input end-guided compliant hinge 24, a first-level lever input point rotating compliant hinge 26, a first-level lever fulcrum rotating compliant hinge 27, a first-level lever output point rotating compliant hinge 29, and a second-level lever input Point-rotation compliant hinge 211 , secondary lever pivot point rotary compliant hinge 212 , secondary lever output point rotary compliant hinge 214 , secondary lever driven rod output end guide compliant hinge 216 . The top of the preloading block 23 is reserved with mounting holes for installing the measuring block and the reflector bracket. The measuring block is installed to facilitate the capacitive sensor 5 to measure the measuring surface of the measuring block. The reflector support can also be installed to use a laser interferometer. The measurement is performed to calibrate or calibrate the capacitive sensor 5, and the influence of the rotation of the preload block 23 on the measurement accuracy of the linear displacement of the capacitive sensor 5 can also be monitored. The force sensor in this embodiment is used to measure the size of the preload force, and it can also monitor the output force value of the piezoelectric ceramic driver 1 in the whole working process and feed it back to the controller, and then combine the preload block 23 and the input end 25 The displacement of the three kinematic branches corresponds to the preload stiffness and the input stiffness. The piezoelectric ceramic driver 1 has a built-in high-precision high-bandwidth strain gauge sensor, and the real-time measurement data is sent to the controller together with the capacitive sensor 5 . The input end guide compliant hinge 24 and the output end guide compliant hinge 216 of the secondary lever driven rod are mainly used to adjust the input/output stiffness and coupling coefficient, and are optimized together with other groups of compliant hinges and flexible rods to achieve the expected stiffness and coupling coefficients.

As shown in Figure 1, the outer fixing base includes a first outer fixing base 6 located on the XOZ plane and the YOZ plane and a second outer fixing base 7 located on the XOY plane, and two groups of first outer fixing bases 6 are vertically connected, The adjacent two sides of the second outer fixing base 7 are respectively connected vertically with the first outer fixing base 6; the joints of the three groups of inner fixing bases 8 are provided with three-way reinforcing ribs 9. In this embodiment, the uniaxial nanopositioning platform 2 is between two, the uniaxial nanopositioning platform 2 and the first outer fixed base 6, the uniaxial nanopositioning platform 2 and the second outer fixed base 7, and the uniaxial nanopositioning platform 2 and the inner fixed base 8, the inner fixed base 8 and the three-way reinforcing rib 9 are respectively fastened together by a number of gaskets, screws and pins, etc., and the three-way reinforcing rib 9 is provided with a second screw that cooperates with the screw The hole 91 and the second pin hole 92 matched with the pin make the fixed part of the uniaxial nanopositioning platform 2 and the bracket of the capacitive sensor 5 relative to the first outer fixing base 6, the second outer fixing base 7, the inner fixing base The seat 8 and the three-way reinforcing rib 9 have no relative displacement.

As shown in FIG. 3 , the first outer fixing bases 6 are respectively located on the XOZ plane and the YOZ plane, and are respectively connected to the uniaxial nanopositioning platform 2 through several screws and pins; The fixed part is reinforced twice; the first heat dissipation grid 62 corresponds to the chute on which the piezoelectric ceramic driver 1 is installed on the uniaxial nanopositioning platform 2 , and the first sinking groove 63 corresponds to the transmission force and displacement on the uniaxial nanopositioning platform 2 . Multiple sets of rods and compliant hinges avoid motion interference, and also dissipate heat through gaps and grid holes to ensure the stability of piezoelectric ceramic driver 1 under high power conditions; the two capacitive sensor brackets 64 are orthogonally distributed, and the The screws and pins are connected to another part of the capacitive sensor bracket for fixing the capacitive sensor 5; in order to strengthen the rigidity of the bracket 64, a number of reinforcing ribs are provided.

As shown in FIG. 4 , the second outer fixing base 7 is located on the XOY plane, and its structure is similar to that of the first outer fixing base, and is connected to the uniaxial nanopositioning platform 2 through several screws and pins respectively; The fixed part on the axis nano-positioning platform 2 is reinforced twice; the second heat dissipation grid 72 corresponds to the chute on which the piezoelectric ceramic driver 1 is installed on the single-axis nano-positioning platform 2, and the second sink 73 corresponds to the single-axis nano-positioning platform 2. Multiple sets of compliant hinges and flexible rods that transmit force and displacement on the upper part avoid motion interference, and also dissipate heat through the second heat dissipation grid 72 to ensure the stability of the piezoelectric ceramic driver 1 and the uniaxial nanopositioning platform 2 under high power conditions sex.

As shown in FIG. 5 , the three inner fixing bases 8 are respectively located on the XOY plane, the XOZ plane and the YOZ plane, and are respectively connected to the uniaxial nanopositioning platform 2 through several screws and pins; several first screw holes 81 correspond to the uniaxial nanopositioning The fixed part on the platform 2 is reinforced three times; the third heat dissipation grid 82 corresponds to the chute on which the piezoelectric ceramic driver 1 is installed on the uniaxial nanopositioning platform 2, and the third sink 84 corresponds to the transmission force and Displacement of multiple sets of compliant hinges and flexible rods avoids motion interference, and also dissipates heat through gaps and grid holes to ensure the stability of piezoelectric ceramic driver 1 and uniaxial nanopositioning platform 2 under high-power conditions; several first The pin hole 83 and the first screw hole 81 are used to connect with the three-way reinforcing rib 9 .

As shown in FIG. 6 , the three-way reinforcing rib 9 has a three-dimensional structure, and the three branch chains are respectively connected to the inner fixed base 8 through a number of screws and pins, so as to improve the rigidity of the inner fixed base 8, and also serve as the entire three-axis tool servo device. Reinforcing ribs to improve the structural rigidity of the device; multiple sets of screw holes and pin holes are reserved to match the flexible design of configuration and size, which are used to integrate into various precision equipment such as different ultra-precision machining machines, precision measurement, and micro-nano manufacturing/ instrument/equipment.

As shown in FIG. 7 , the three-axis end effector 3 includes three second motion branches corresponding to the X-axis, the Y-axis and the Z-axis, which are composed of multiple sets of compliant hinges and flexible rods; The second connecting end, the connecting rod, the input point compliant hinge and the decoupling guide compliant hinge are connected in series. Specifically, the second connecting ends of the three-axis end effector 3 in the three directions of Z, Y and X are connected to the Z-direction 311, Y-direction 321, and X-direction 331 through a number of sinks, screws and The pins are respectively connected with the three single-axis nano-positioning platforms 2; the three-axis end effector 3 includes three second motion branches composed of multiple sets of compliant hinges and flexible rods, corresponding to the Z-axis, the Y-axis and the X-axis, respectively. The bar shafts are connected in series with axial compliant hinges, rods and several groups of guide compliant hinges, etc.; for the Z-axis direction, the Z-direction connecting end 311, the Z-direction connecting rod 312, the Z-direction input point compliant hinge 313, and the Z-Y decoupling are connected in series in sequence. Guide compliant hinge 314, Z-X decoupling guide compliant hinge 315; for the Y-axis direction, connect Y-direction connecting end 321, Y-direction connecting rod 322, Y-direction input point compliant hinge 323, Y-Z decoupling guide compliant hinge 324, Y-X decoupling in sequence Coupling guide compliant hinge 325; for the X-axis direction, connect X-direction connecting end 331, X-direction connecting rod 332, X-direction input point compliant hinge 333, X-Z decoupling guide compliant hinge 334, X-Y decoupling guide compliant hinge 335 in sequence; The multiple sets of compliant hinges of the single-axis nanopositioning platform 2 realize guidance and multi-axis decoupling, and it is easy to design a multi-axis linkage controller; the three-axis end effector 3 reinforces the diamond tool 4 through several screws; The shaft end effector 3 has three degrees of freedom of linear axes, and the diamond tool 4 also has the same degrees of freedom; the three-axis end effector 3 is provided with four measurement surfaces, corresponding to four capacitive sensors 5 respectively; The displacement of the shaft end effector 3 on the three orthogonal linear axes X/Y/Z in space is directly measured by the capacitive sensor 5 and sent to the controller (not shown in the figure); Capacitive sensors 5 can be calibrated with each other, and can also measure the angular coupling displacement other than the linear motion axis of the three-axis end effector; the three-axis end effector 3 has a reserved interface, which can be connected to a laser interferometer (not shown in the figure), laser ruler (not shown in the figure), a three-coordinate measuring machine (not shown in the figure) or a laser tracker (not shown in the figure), etc., used to evaluate, check or verify the measurement data of the capacitive sensor 5 of the device itself. Verification; the mounting accuracy of the capacitive sensor 5, the parallelism with the measured surface and the initial distance are determined by using a feeler gauge (not shown in the figure); the capacitive sensor 5 used in this embodiment is a columnar structure, and a chip type can also be used structure or other types of micro-displacement sensors for measurement; the three-axis end effector 3 used in this embodiment can also be externally connected to a precision measuring head, imaging device, sample stage, etc., and integrated into various types of precision equipment/instruments/equipment.

The statics, kinematics and dynamic characteristics of the compliant parallel mechanism in this embodiment depend on multiple sets of compliant hinges and flexible rods of the three kinematic branches. By optimizing the design of the structural parameters, it is possible to achieve the optimal performance of multiple performance indicators of the mechanism. Combination optimization to meet the preference requirements for performance graphs in different application scenarios.

Obviously, the above-mentioned embodiments of the present invention are only examples for clearly illustrating the present invention, rather than limiting the embodiments of the present invention. For those of ordinary skill in the art, changes or modifications in other different forms can also be made on the basis of the above description. There is no need and cannot be exhaustive of all implementations here. Any modifications, equivalent replacements and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the claims of the present invention.

Claims (4)

1. A triaxial cutter servo device based on a flexible parallel mechanism is characterized by comprising an outer side fixed base, an inner side fixed base, a single-axis nanometer positioning platform for transmitting motion through a first motion branched chain and a triaxial end effector for guiding and decoupling through a second motion branched chain, wherein three groups of the outer side fixed base, the inner side fixed base and the single-axis nanometer positioning platform are orthogonal in pairs and are respectively positioned on an XOY plane, an XOZ plane and a YOZ plane; the single-shaft nanometer positioning platform is arranged between the outer side fixing base and the inner side fixing base and is connected with the three-shaft end effector; the first moving branched chain and the second moving branched chain are connected to form three moving branched chains for transmitting force/displacement/movement generated by the piezoelectric ceramic driver to the three-axis end effector, and the three moving branched chains are connected in parallel and are orthogonal in pairs; the three-axis end effector is connected with a cutter; the three-axis end effector is provided with a capacitance sensor for measuring displacement of the cutter on three spatial orthogonal linear axes X/Y/Z, and the capacitance sensor is connected with a controller; the output end of the controller is connected with a piezoelectric ceramic driver, the piezoelectric ceramic driver is connected to the input ends of the single-axis nanometer positioning platforms, and the three-axis end effector is connected to the output ends of the three single-axis nanometer positioning platforms;

the first motion branched chain comprises an input end guide flexible hinge, an input end, a first-stage lever input point rotary flexible hinge, a first-stage lever fulcrum rotary flexible hinge, a first-stage lever driving rod, a first-stage lever output point rotary flexible hinge, a first-stage lever driven rod and a first connecting end which are sequentially connected in series; one end of the piezoelectric ceramic driver is connected with the single-shaft nanometer positioning platform through a jackscrew, the piezoelectric ceramic driver is in gapless connection with the input end, and the first connecting end is connected with the three-shaft end effector;

a second-level lever input point rotary type flexible hinge, a second-level lever fulcrum rotary type flexible hinge, a second-level lever driving rod, a second-level lever output point rotary type flexible hinge, a second-level lever driven rod and a second-level lever driven rod output end guide flexible hinge which are connected in sequence are further arranged between the first-level lever driven rod and the first connecting end;

the second moving branched chain comprises a second connecting end, a connecting rod, an input point flexible hinge and a decoupling guide flexible hinge, the second connecting end, the connecting rod, the input point flexible hinge and the decoupling guide flexible hinge are sequentially connected in series, and the second connecting end is connected with the first connecting end;

the outer side fixing bases comprise first outer side fixing bases located on an XOZ plane and a YOZ plane and second outer side fixing bases located on an XOY plane, two groups of first outer side fixing bases are vertically connected, and two adjacent sides of each second outer side fixing base are respectively and vertically connected with the first outer side fixing bases;

the first outer side fixing base is provided with a first connecting hole used for being connected with the single-axis nanometer positioning platform, a first sinking groove used for avoiding motion interference with each component on a motion branch chain to which the single-axis nanometer positioning platform belongs, a first heat dissipation grid used for dissipating heat generated by the piezoelectric ceramic driver and two groups of orthogonally distributed capacitance sensor supports, the first heat dissipation grid penetrates through the first outer side base, and the first sinking groove is formed in the inner side of the first outer side fixing base; one end of the capacitive sensor bracket is arranged to protrude out of the first outer side fixing base and is connected with the capacitive sensor;

the second outside fixed baseplate is equipped with the second connecting hole that is used for being connected with triaxial nanometer positioning platform, is used for avoiding producing the heavy groove of second that the motion is interfered and be used for dispelling piezoceramics driver production of heat with each part on the unipolar nanometer positioning platform affiliated motion branch chain, the second cooling grid runs through the setting of second outside base, the inboard of second outside fixed baseplate is located to the heavy groove of second.

2. The compliant parallel mechanism based three-axis tool servo device of claim 1, wherein the end face of the jackscrew is provided with a ball in surface contact, the ball is provided with a force sensor for measuring pre-tightening force in point contact, and a pre-tightening block is arranged between the force sensor and the piezoelectric ceramic driver; the force sensor is connected with the controller.

3. The compliant parallel mechanism based three-axis tool servo device as claimed in claim 2, wherein mounting holes for mounting the measuring block and the mirror holder are reserved on the top of the pre-tightening block.

4. The compliant parallel mechanism based three-axis tool servo device of claim 1, wherein three-way stiffeners are provided at the joints of three sets of inner fixed bases; inboard fixed baseplate is equipped with and is used for dispelling the thermal third heat dissipation bars of piezoceramics driver production, piezoceramics driver's drive voltage line and sensor signal line pass the setting of third heat dissipation bars.

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