CN217282754U

CN217282754U - Piezoelectric stick-slip rotary positioning platform

Info

Publication number: CN217282754U
Application number: CN202220933555.1U
Authority: CN
Inventors: 刘希同
Original assignee: Shandong University
Current assignee: Shandong University
Priority date: 2022-04-20
Filing date: 2022-04-20
Publication date: 2022-08-23
Anticipated expiration: 2032-04-20

Abstract

The utility model discloses a piezoelectricity glues smooth rotational positioning platform designs rotational positioning platform technical field. Comprises a base part, a driving part, a transmission part, an execution part and a sensing feedback part; the base part comprises a base body, a driving part and a sensing feedback part are embedded in the upper surface of the base body, a central hole is formed in the center of the base body, a transmission part capable of rotating relative to the base body is arranged in the central hole, an execution part is arranged at the top of the transmission part, the output end of the driving part protrudes out of the surface of the base body and contacts with the execution part, and the sensing feedback part is used for measuring the rotating angle of the execution part. The utility model discloses overall structure is simple compact more, and small, the stroke is big, the drive speed is fast, the drive efficiency is high and positioning accuracy is high, can satisfy each item requirement of precision positioning system, realizes two-way big stroke angular rotation.

Description

Piezoelectric stick-slip rotary positioning platform

Technical Field

The utility model relates to a rotational positioning platform technical field especially relates to a piezoelectricity glues smooth rotational positioning platform.

Background

The statements in this section merely provide background information related to the present disclosure and may not necessarily constitute prior art.

With the rapid development of science and technology, a trans-scale precision actuator with large motion stroke and high displacement resolution is an indispensable key technology in the fields of bioengineering, space technology, aerospace technology, integrated circuits, modern medical treatment, MEMS and the like. For a rotary positioning platform, a large motion stroke and high resolution are contradictory problems, and with the rapid development of high-precision numerical control processing technology, high-speed scanning detection technology and the like, higher requirements are put forward on the stroke and precision of rotary positioning.

The existing rotary positioning platform has the defects of complex and non-compact structure, large volume, low driving speed and low driving efficiency, cannot realize large-stroke rotation due to low positioning precision, and is difficult to be applied to a precision positioning system.

SUMMERY OF THE UTILITY MODEL

In order to solve the problem, the utility model provides a piezoelectricity glues smooth rotational positioning platform, overall structure is compact simple more, and is small, the stroke is big, the drive speed is fast, the drive efficiency is high and positioning accuracy is high, can satisfy each item requirement of precision positioning system, realizes two-way big stroke angle rotation.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

the utility model relates to a piezoelectric stick-slip rotary positioning platform, which comprises a base part, a driving part, a transmission part, an execution part and a sensing feedback part; the base part comprises a base body, a driving part and a sensing feedback part are embedded in the upper surface of the base body, a central hole is formed in the center of the base body, a transmission part capable of rotating relative to the base body is arranged in the central hole, an execution part is arranged at the top of the transmission part, the output end of the driving part protrudes out of the surface of the base body and contacts with the execution part, and the sensing feedback part is used for measuring the rotating angle of the execution part.

Preferably, the driving part comprises a driver, a piezoelectric ceramic and a friction ceramic output end; the driver comprises a first transmission hinge, a second transmission hinge, a piezoelectric ceramic mounting groove and a friction ceramic mounting groove, wherein piezoelectric ceramic is arranged in the piezoelectric ceramic mounting groove, and a friction ceramic output end is arranged in the friction ceramic mounting groove.

Preferably, the transmission part comprises a transmission shaft, an angular contact bearing and a bearing inner ring fixing piece; the transmission shaft comprises a first shaft section, a second shaft section and a third shaft section, and the second shaft section and the third shaft section form a shaft shoulder; the bearing inner ring fixing piece is detachably connected with the first shaft section of the transmission shaft, and the angular contact bearing is arranged between the upper end face of the bearing inner ring fixing piece and the shaft shoulder.

Preferably, a circular boss is arranged on the inner wall of the central hole of the base body, the lower end face of the outer ring of the angular contact bearing is in contact with the upper end face of the circular boss, the outer ring of the angular contact bearing is in interference fit with the inner wall of the central hole, and the inner ring of the angular contact bearing is in interference fit with the second shaft section.

Preferably, the executing part comprises a disc tail end, an annular friction ceramic plate, a circular grating ruler and a grating ruler fixing part; the terminal third shaft section detachable with the transmission shaft that is connected of disc, the terminal lower part of disc is equipped with outer boss and grating chi mounting, be provided with circular grating chi between outer boss and the grating chi mounting, be provided with annular friction potsherd between the outside of outer boss and the terminal lower extreme terminal surface of disc.

Preferably, the grating ruler fixing piece is annular, an inner ring of the grating ruler fixing piece is provided with an inner boss, and the inner boss is detachably connected with the tail end of the disc.

Preferably, the friction ceramic output end of the driving part protrudes out of the upper surface of the base body to be in contact with the annular friction ceramic plate of the actuating part.

Preferably, the sensing feedback part is a grating, and the grating and the circular grating scale are matched with each other to measure the rotation angle of the execution part.

Preferably, the friction ceramic output end and the annular friction ceramic plate are alumina ceramic plates.

Preferably, the base part further comprises an upper shell and a lower shell, and the upper shell, the lower shell and the base body are detachably connected; the base body is circular, and the upper shell and the lower shell are circular; the upper surface of the base body is provided with a driver mounting groove and a grating mounting groove; the two driver mounting grooves are symmetrically arranged, and a plurality of fixing holes and wiring holes are formed in the driver mounting groove and the grating mounting groove; the back of the base body is also provided with a circular groove.

The drive mode of the piezoelectric stick-slip rotary positioning platform is as follows:

applying a triangular signal to the piezoelectric ceramic;

when an ascending slope signal with a smaller slope and a descending slope signal with a larger slope are applied, the tail end of the disc firstly carries out 'sticky' motion by virtue of static friction force between the friction ceramic output end and the annular friction ceramic sheet and then carries out 'sliding' motion by virtue of dynamic friction force between the friction ceramic output end and the annular friction ceramic sheet, so that the forward rotation of the rotary platform is realized; when an ascending slope signal with a larger slope and a descending slope signal with a smaller slope are applied, the tail end of the disc firstly performs sliding motion by virtue of the dynamic friction force between the friction ceramic output end and the annular friction ceramic sheet and then performs sticking motion by virtue of the static friction force between the friction ceramic output end and the annular friction ceramic sheet, so that the rotary platform can rotate reversely.

Compared with the prior art, the beneficial effects of the utility model are that:

1. the utility model discloses rotational positioning platform simple structure, compactness, driver and grating are embedded in the base, greatly reduce rotary platform's height. The invention has great advantages in high compactness, and is particularly suitable for occasions with limited platform height.

2. The utility model discloses a driver direct drive execution part's drive mode, rather than the indirect drive mode of driver drive transmission shaft, therefore the invention can reduce energy loss, improves drive efficiency, increases drive power.

3. The utility model discloses set up the sensing feedback part, use the grating as the sensor, feed back the rotation angle that the grating was gathered to the controller and carry out closed-loop control, therefore the closed-loop resolution of the invention is high, possess high location rotation accuracy.

4. The utility model discloses the drive division uses the aluminium oxide potsherd, has guaranteed great frictional force between drive and actuating mechanism to make the invention possess great drive power and drive speed, and the dynamic property is good.

5. The utility model is based on stick-slip principle, has a large rotation range, and can realize full-stroke movement; and by applying different control signals, the bidirectional movement of the rotary positioning platform can be realized.

Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Drawings

The accompanying drawings, which form a part of the specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention without unduly limiting the scope of the invention.

FIG. 1 is a schematic view of the overall structure of the present invention;

FIG. 2 is a schematic view of the overall structural assembly of the present invention;

FIG. 3 is a schematic perspective view of a base body according to the present invention;

FIG. 4 is a schematic perspective view of another embodiment of the base body of the present invention;

FIG. 5 is a schematic view of the driving portion of the present invention;

FIG. 6 is a schematic view of a driver according to the present invention;

FIG. 7 is a schematic view of the structure of the transmission part of the present invention;

FIG. 8 is a front view of the transmission part of the present invention;

FIG. 9 is a schematic sectional view taken along the line A-A in FIG. 8;

FIG. 10 is a schematic view of a drive shaft according to the present invention;

FIG. 11 is a schematic view of a bearing inner race fixing member according to the present invention;

FIG. 12 is a schematic view of the end structure of the disk of the present invention;

FIG. 13 is a cross-sectional view of an implementation of the present invention;

FIG. 14 is a schematic view of a grating ruler fixing member according to the present invention;

FIG. 15 is a control excitation signal for the piezoelectric stick-slip rotational positioning stage of the present invention;

wherein, 1: a base part, 1-1: a base body, 1-1-1: a central hole, 1-1-2: a circular boss, 1-1-3: a grating mounting groove, 1-1-3-1: threaded hole, 1-1-3-2: rectangular through holes, 1-1-4 parts of driver mounting grooves, 1-1-4-1 parts of drivers: threaded hole, 1-1-4-2: through holes, 1-1-5: circular grooves, 1-1-6: wire outlet holes, 1-1-7: threaded holes, 1-2: upper shell, 1-2-1: 1-3 of counter sink, namely lower shell, 1-3-1 of counter sink: a countersunk hole; 2: drive portion, 2-1: driver, 2-1-1: through hole, 2-1-2: through hole, 2-1-3: first transmission hinge, 2-1-4: no. two transmission hinges, 2-1-5: piezoelectric ceramic mounting groove, 2-1-6: friction ceramic mounting groove, 2-2: piezoelectric ceramic, 2-3: rubbing the ceramic output end; 3: transmission part, 3-1: drive shaft, 3-1-1: first shaft segment, 3-1-2: second shaft section, 3-1-3: third shaft segment, 3-1-4: external thread, 3-1-5: shaft shoulder, 3-1-6: threaded hole, 3-2: angular contact bearing, 3-3: bearing inner race fixing piece, 3-3-1: an internal thread; 4: execution section, 4-1: disc end, 4-1-1: clear hole, 4-1-2: outer boss, 4-1-3: threaded hole, 4-1-4: counter bore, 4-2: annular friction ceramic plate, 4-3: circular grating ruler, 4-4: fixing part of grating ruler, 4-4-1: inner boss, 4-4-2: a countersunk hole; 5: sensory feedback section, 5-1: and (4) a grating.

Detailed Description

The present invention will be further explained with reference to the accompanying drawings and examples.

It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the invention. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments in accordance with the invention. As used herein, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise, and it should be understood that the terms "comprises" and "comprising", and any variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

In the case of conflict, the embodiments and features of the embodiments of the present invention can be combined with each other.

Example one

As shown in fig. 1 and fig. 2, the piezoelectric stick-slip rotary positioning platform of the present invention includes a base portion 1, a driving portion 2, a transmission portion 3, an executing portion 4, and a sensing feedback portion 5.

The base part 1 comprises a base body 1-1, an upper shell 1-2 and a lower shell 1-3; as shown in fig. 3 and 4, the base body 1-1 is a circular ring-shaped part, and a central hole 1-1-1 and a circular boss 1-1-2 are reserved in the base body 1-1, wherein the transmission part 3 is disposed in the central hole 1-1-1, and the axial positioning and fixing of the base body 1-1 and a bearing inner ring in the transmission part 3 are realized through the circular boss 1-1-2, that is, the positioning of the transmission part 3 is realized.

The upper surface of the base body 1-1 is provided with three mounting grooves, namely a grating mounting groove 1-1-3 and two driver mounting grooves 1-1-4, and the back surface of the base body 1-1 is also provided with a circular groove 1-1-5. Wherein, the two driver installation grooves 1-1-4 are symmetrically distributed along the circumferential direction of the upper surface of the base body 1-1, and the included angle between the grating installation groove 1-1-3 and the driver installation groove is 90 degrees. Four threaded holes are formed in the driver mounting groove, two threaded holes 1-1-4-1 are used for positioning and fixing the driver 2-1, and two through holes 1-1-4-2 are used for facilitating distribution of power lines of the piezoelectric ceramic 2-2, and the lines penetrate out of the through holes. The grating mounting groove 1-1-3 is provided with two threaded holes 1-1-3-1 to realize the fixation of the grating 5-1; one side of the grating mounting groove 1-1-3 is provided with a rectangular through hole 1-1-3-2, which is convenient for routing the signal line of the grating 5-1. The power line of the piezoelectric ceramic 2-2 is concentrated in the circular groove 1-1-5 on the back surface of the base, and penetrates out of the wire outlet hole 1-1-6 together with the signal line of the grating 5-1.

The base body 1-1 is provided with threaded holes 1-1-7 along the circumference of the upper surface and the lower surface, so that the upper shell and the lower shell can be installed and positioned.

As shown in figure 1, the upper shell 1-2 and the lower shell 1-3 are circular ring-shaped parts, countersunk holes 1-2-1 and 1-3-1 are uniformly distributed on the circumference, and the upper shell, the lower shell and the base body 1-1 are installed and fixed through bolt connection.

As shown in FIG. 5, the driving portion 2 includes a driver 2-1, a piezoelectric ceramic 2-2, and a friction ceramic plate 2-3.

As shown in FIG. 6, the driver 2-1 is integrally formed by wire cutting, and comprises two through holes 2-1-1 and 2-1-2, a first transmission hinge 2-1-3, a second transmission hinge 2-1-4, a piezoelectric ceramic mounting groove 2-1-5 and a friction ceramic mounting groove 2-1-6. And a bolt penetrates through the through hole 2-1-1 and the threaded hole 1-1-4-1, the driver 2-1 is fixed on the base body 1-1, the piezoelectric ceramic 2-2 is placed in the piezoelectric ceramic mounting groove 2-1-5, and the friction ceramic output end 2-3 is adhered in the friction ceramic mounting groove 2-1-6 by using epoxy resin glue. When the piezoelectric ceramic 2-2 is extended or shortened, the motion is transmitted to the friction ceramic output end 2-3 of the driver 2-1 through the deformation rotation of the transmission hinges 2-1-3 and 2-1-4, and the friction ceramic output end 2-3 is contacted with the annular friction ceramic piece 4-2 of the execution part 4, so that the friction ceramic output end 2-3 can drive the disc tail end 4-1 of the execution part 4 to rotate through static friction force, and the linear motion is converted into the rotary motion. The driver 2-1 of the invention directly transmits the motion to the execution part 4 instead of driving the transmission part 3, and the direct driving mode reduces energy loss and increases driving force.

As shown in fig. 7-8, the transmission part 3 includes a transmission shaft 3-1, an angular contact bearing 3-2, and a bearing inner ring fixture 3-3, wherein the bearing bears the axial gravity, so that the angular contact bearing capable of bearing a large axial load is selected to improve the bearing capacity of the bearing and improve the rotation precision of the turntable.

As shown in FIG. 10, the transmission shaft 3-1 is a stepped shaft, the first shaft section 3-1-1 is provided with an external thread 3-1-4, the second shaft section 3-1-2 and the third shaft section 3-1-3 form a shaft shoulder 3-1-5, and the end of the third shaft section 3-1-3 is provided with four threaded holes 3-1-6.

As shown in fig. 11, the bearing inner ring fixing piece 3-3 is a circular self-made nut, and the inner ring is provided with an internal thread 3-3-1 which is matched with an external thread 3-1-4 of the transmission shaft 3-1; the inner ring of the angular contact bearing 3-2 is fixed by the end face of the bearing inner ring fixing piece 3-3 and the shaft shoulder 3-1-5, so that the axial fixation of the inner ring of the angular contact bearing 3-2 is realized.

As shown in fig. 9 and 10, the inner ring and the outer ring of the angular contact bearing 3-2 are in interference fit, so that the circumferential positioning and fixing of the bearing are realized. The inner ring of the angular contact bearing 3-2 is contacted with the second shaft section 3-1-2, the outer ring is contacted with the inner wall of the central hole 1-1-1, and the end face of the outer ring of the bearing is contacted with the circular boss 1-1-2, so that the positioning and fixing of the outer ring of the bearing are realized, and the positioning of the transmission part 3 relative to the base part 1 is also realized.

As shown in FIG. 10, the end of the third shaft section 3-1-3 of the transmission shaft 3-1 is provided with four threaded holes 3-1-6 which are matched with four counter bores 4-1-4 in the disc tail end 4-1, and the transmission shaft 3-1 is fixed with the disc tail end 4-1 of the execution part 4 through bolt connection. With the movement of the transmission part, the execution part can rotate.

As shown in fig. 13, the executing part 4 includes a disc end 4-1, an annular friction ceramic plate 4-2, a circular grating scale 4-3 and a grating scale fixing part 4-4.

As shown in fig. 12, the tail end 4-1 of the disc is a circular ring-shaped part, the central part is a light through hole 4-1-1, the lower part is provided with an outer boss 4-1-2, the inner ring of the outer boss 4-1-2 realizes the positioning of the circular grating ruler 4-3, and the outer ring of the outer boss realizes the positioning of the annular friction ceramic plate 4-2; the central part of the disc is provided with four threaded holes 4-1-3 and four counter bores 4-1-4, wherein the threaded holes 4-1-3 are matched with the counter bores 4-4-2 of the grating ruler fixing piece 4-4, the grating ruler fixing piece 4-4 is positioned and fixed through bolt connection, and the counter bores 4-1-4 are matched with the threaded holes 3-1-6, so that the transmission shaft 3-1 is fixed with the tail end 4-1 of the disc.

As shown in fig. 13, the annular friction ceramic plate 4-2 is a thin annular part made of an aluminum oxide ceramic plate, and is insulated, wear-resistant and high-temperature-resistant, so that the friction force of the driver can be increased to improve the driving force and the driving speed. The annular friction ceramic plate 4-2 is adhered to the tail end 4-1 of the disc through epoxy resin glue, and similarly, the circular grating ruler 4-3 is adhered to the tail end 4-1 of the disc through the epoxy resin glue.

As shown in fig. 14, the grating ruler fixing member 4-4 is a circular ring-shaped member, a boss 4-4-1 is provided on the inner ring, and a counter bore 4-4-2 is provided on the boss 4-4-1 to fix the grating ruler fixing member to the end of the disc.

As shown in fig. 13, the grating ruler fixing member 4-4 can press the circular grating ruler 4-3 by using the portion of the outer ring with a smaller thickness, so as to fix the circular grating ruler in the Z direction.

As shown in fig. 2, the sensory feedback portion 5 is a grating 5-1. The grating precision is higher, measures displacement value s, and if the radius of circular grating chi 4-3 is set as r, then rotation angle alpha is s/r, can convert the displacement signal that the grating read into rotatory angle, feeds back the rotation angle to the controller, realizes closed-loop control. For example, a PID controller, or a tamper-resistant H ∞ controller is added. Therefore, the invention has higher rotation precision, selects the embedded grating with compact structure and can be fixed in the grating mounting groove through bolt connection. In practical use, the present embodiment may be replaced by other sensors for measuring displacement or rotation angle.

Example two

The embodiment is a driving mode and a bidirectional rotation control method of a piezoelectric stick-slip rotary positioning platform, and the method comprises the following steps:

in this embodiment, a triangular signal is applied to the piezoelectric ceramic 2-2, as shown in fig. 15B, when an ascending ramp signal with a small slope and a descending ramp signal with a large slope are applied, the piezoelectric ceramic 2-2 slowly extends and then rapidly contracts, the stick-slip platform performs a "stick" motion, that is, a static friction force exists between the friction ceramic output end 2-3 and the annular friction ceramic piece 4-2, the disc end 4-1 and the friction ceramic output end 2-3 are relatively static, and the disc 4-1 rotates in a forward direction by α 1; then, the sliding motion is carried out, namely, the dynamic friction force exists between the output end 2-3 of the friction ceramic and the annular friction ceramic piece 4-2, the tail end 4-1 of the disk and the output end 2-3 of the friction ceramic move relatively, and at the moment, the disk rotates in the reverse direction by alpha 2. The disc ends 4-1 are rotated forward by a positive angle (α 1- α 2) during one cycle by a stick-slip motion.

Similarly, if the signal shown in A of FIG. 15 is applied to the piezoelectric ceramic 2-2, the disk end 4-1 will perform a "slip" motion in the forward direction and then a "stick" motion in the reverse direction, i.e., rotate α 3 in the forward direction and then rotate α 4 in the reverse direction, and rotate the disk end 4-1 in the reverse direction by the angle (α 4- α 3) in one cycle. The angle α is an absolute value.

In summary, the piezoelectric ceramic 2-2 is applied with a rising ramp signal and a falling ramp signal with different slopes, and the rotary platform can be switched between two motion states of 'sticky' and 'slippery'. Each stick-slip motion is called as one step, and a plurality of periodic signals are applied to realize stepping motion, so that the full-stroke motion can be realized. The invention has a great rotation range and can realize bidirectional large-stroke angle rotation by applying different triangular signals.

In the embodiment, the grating 5-1 is integrated on the stick-slip rotating platform, so that the rotation angle can be fed back, and a PID (proportion integration differentiation) controller or other controllers are used for carrying out closed-loop control on the stick-slip rotating platform, so that the stick-slip rotating platform has extremely high rotation precision.

Although the present invention has been described with reference to the accompanying drawings, it is not intended to limit the scope of the present invention, and those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without inventive work are still within the scope of the present invention.

Claims

1. The piezoelectric stick-slip rotary positioning platform is characterized by comprising a base part (1), a driving part (2), a transmission part (3), an execution part (4) and a sensing feedback part (5); the base part (1) comprises a base body (1-1), a driving part (2) and a sensing feedback part (5) are embedded in the upper surface of the base body (1-1), a central hole (1-1-1) is formed in the center of the base body (1-1), a transmission part (3) capable of rotating relative to the base body (1-1) is arranged in the central hole (1-1-1), an execution part (4) is arranged at the top of the transmission part (3), the output end of the driving part (2) protrudes out of the surface of the base body (1-1) and is in contact with the execution part (4), and the sensing feedback part (5) is used for measuring the rotating angle of the execution part (4).

2. The piezoelectric stick-slip rotary positioning stage according to claim 1, wherein the drive section (2) comprises a driver (2-1), a piezoelectric ceramic (2-2) and a friction ceramic output (2-3); the driver (2-1) comprises a first transmission hinge (2-1-3), a second transmission hinge (2-1-4), a piezoelectric ceramic mounting groove (2-1-5) and a friction ceramic mounting groove (2-1-6), wherein piezoelectric ceramic (2-2) is arranged in the piezoelectric ceramic mounting groove (2-1-5), and a friction ceramic output end (2-3) is arranged in the friction ceramic mounting groove (2-1-6).

3. The piezoelectric stick-slip rotary positioning platform as claimed in claim 2, wherein the transmission part (3) comprises a transmission shaft (3-1), an angular contact bearing (3-2) and a bearing inner ring fixing piece (3-3); the transmission shaft (3-1) comprises a first shaft section (3-1-1), a second shaft section (3-1-2) and a third shaft section (3-1-3), and the second shaft section (3-1-2) and the third shaft section (3-1-3) form a shaft shoulder (3-1-5); the bearing inner ring fixing piece (3-3) is detachably connected with the first shaft section (3-1-1) of the transmission shaft (3-1), and the angular contact bearing (3-2) is arranged between the upper end face of the bearing inner ring fixing piece (3-3) and the shaft shoulder (3-1-5).

4. The piezoelectric stick-slip rotary positioning platform as claimed in claim 3, wherein a circular boss (1-1-2) is arranged on the inner wall of the central hole (1-1-1) of the base body (1-1), the lower end face of the outer ring of the angular contact bearing (3-2) is in contact with the upper end face of the circular boss (1-1-2), the outer ring of the angular contact bearing (3-2) is in interference fit with the inner wall of the central hole (1-1-1), and the inner ring of the angular contact bearing (3-2) is in interference fit with the second shaft section (3-1-2).

5. The piezoelectric stick-slip rotary positioning platform according to claim 4, wherein the execution part (4) comprises a disc tail end (4-1), an annular friction ceramic plate (4-2), a circular grating ruler (4-3) and a grating ruler fixing part (4-4); the disc tail end (4-1) is detachably connected with a third shaft section (3-1-3) of the transmission shaft (3-1), an outer boss (4-1-2) and a grating ruler fixing piece (4-4) are arranged on the lower portion of the disc tail end (4-1), a circular grating ruler (4-3) is arranged between the outer boss (4-1-2) and the grating ruler fixing piece (4-4), and an annular friction ceramic piece (4-2) is arranged between the outer side of the outer boss (4-1-2) and the lower end face of the disc tail end (4-1).

6. The piezoelectric stick-slip rotary positioning platform as claimed in claim 5, wherein the grating ruler fixing member (4-4) is annular, an inner boss (4-4-1) is arranged on an inner ring of the grating ruler fixing member (4-4), and the inner boss (4-4-1) is detachably connected with the end (4-1) of the disc.

7. The piezoelectric stick-slip rotary positioning platform according to claim 6, wherein the friction ceramic output end (2-3) of the driving part (2) protrudes out of the upper surface of the base body (1-1) to be in contact with the annular friction ceramic plate (4-2) of the executing part (4).

8. The piezoelectric stick-slip rotary positioning platform according to claim 7, wherein the sensing feedback part (5) is a grating (5-1), and the grating (5-1) and the circular grating ruler (4-3) are matched with each other to measure the rotation angle of the execution part (4).

9. The piezoelectric stick-slip rotary positioning platform of claim 8, wherein the friction ceramic output end (2-3) and the annular friction ceramic plate (4-2) are alumina ceramic plates.

10. The piezo-electric stick-slip rotational positioning platform of claim 9, wherein the base portion (1) further comprises an upper housing (1-2) and a lower housing (1-3), the upper housing (1-2), the lower housing (1-3) and the base body (1-1) are detachably connected; the base body (1-1) is circular, and the upper shell (1-2) and the lower shell (1-3) are circular; the upper surface of the base body (1-1) is provided with a driver mounting groove (1-1-4) and a grating mounting groove (1-1-3); the two driver mounting grooves (1-1-4) are symmetrically arranged, and a plurality of fixing holes and wiring holes are formed in the driver mounting grooves (1-1-4) and the grating mounting grooves (1-1-3); the back surface of the base body (1-1) is also provided with a circular groove (1-1-5).