A durable three-axis drive mechanism for minimally invasive cell puncture instrument

Abstract

The present invention proposes a durable three-axis drive mechanism for a minimally invasive cell puncture instrument, which belongs to the field of precision transmission technology. The drive mechanism includes an X-degree-of-freedom motion table, a Y-degree-of-freedom motion table, and a Z-degree-of-freedom motion table connected in series; the X-degree-of-freedom motion table, the Y-degree-of-freedom motion table, and the Z-degree-of-freedom motion table all include a base, on which a stator assembly, a pre-tightening magnet, a magnetic friction foot, and a link magnet and a piezoelectric body are installed; the stator assembly consists of a slide rail and a slider, the slide rail is fixed on the base, and the slider forms a sliding fit with the slide rail, and the sliding directions of the sliders of the X-degree-of-freedom motion table, the Y-degree-of-freedom motion table, and the Z-degree-of-freedom motion table are their degrees of freedom directions, respectively. The present invention realizes minimally invasive cell puncture based on the inertial drive principle, and has the advantages of simple structure, strong wear resistance, wear self-adaptation, modular replacement, and no need for pre-tightening and loosening prevention, and has the potential to achieve durable drive.

Description

Technical Field

[0001] The invention belongs to the technical field of precision transmission, and in particular relates to a durable three-axis driving mechanism of a minimally invasive cell puncture instrument. Background Art

[0002] Applying high-frequency excitation during artificial insemination cell puncture can effectively reduce cell damage. This method can also use a wider injection needle to deliver large volumes of editing materials, thereby improving targeting efficiency. Melissa A. Scott et al. introduced a piezoelectric drive unit in the injection pipette part to reduce cell puncture damage through high-frequency excitation. In the direct modification of the fertilized egg genome, this method uses a wider injection needle than pronuclear injection, so it allows a larger volume of editing materials to be transported to the fertilized egg, thereby improving targeting efficiency and eliminating the clogging problem that often occurs in pronuclear injection. The application of piezoelectric inertial excitation drive to cell micromanipulation systems can combine minimally invasive puncture functions, simplify the drive system, and reduce the drive voltage. At present, the problem that restricts the application of piezoelectric inertial drive is that its durability is weak and it is difficult to meet the needs of frequent reciprocating motion. This type of drive is driven by the friction between the friction foot and the slider, and the relative movement of the friction surface will cause wear problems.

[0003] The stroke of a piezoelectric vibrator is only a few microns or more than ten microns. It cannot meet the needs of centimeter-level cell micromanipulation when used alone. At present, scholars in the field have connected commercial cell micromanipulation manipulators in series with piezoelectric vibrators to enable the cell operating system to have minimally invasive puncture functions, but the drive system is relatively complex. The application of piezoelectric inertial excitation drive to cell micromanipulation systems can have minimally invasive puncture functions, simplify the drive system, and reduce the drive voltage. However, the relative movement of the friction surface between the friction foot and the slider of the current cross-scale piezoelectric drive will cause wear problems. When the wear accumulates to a certain extent, the positive pressure between the drive foot and the slider will fluctuate greatly, and even wear will occur, which will cause system instability and ultimately cause drive failure. Summary of the invention

[0004] In order to solve the problems in the prior art, the present invention proposes a durable three-axis driving mechanism for a minimally invasive cell puncture instrument. The present invention utilizes the output characteristics of the piezoelectric inertial excitation drive to achieve minimally invasive cell puncture and greatly improves the durability of the driving mechanism.

[0005] The technical solution adopted by the present invention is as follows:

[0006] In a first aspect, the present invention provides a durable three-axis drive mechanism for a minimally invasive cell puncture instrument, comprising an X-degree-of-freedom motion table, a Y-degree-of-freedom motion table, and a Z-degree-of-freedom motion table;

[0007] The X-degree-of-freedom motion table, the Y-degree-of-freedom motion table, and the Z-degree-of-freedom motion table all include a base, on which a stator assembly, a pre-tightening magnet, a magnetic friction foot, and a link magnet and a piezoelectric body are installed; the stator assembly consists of a slide rail and a slider, the slide rail is fixed on the base, and the slider forms a sliding fit with the slide rail, and the sliding direction of the slider of each motion table is the direction of its degree of freedom, and a carrier plate is fixed on the slider, and the carrier plate is used to install the substrate of other motion tables or the pipette of the cell minimally invasive puncture instrument;

[0008] The base is provided with a piezoelectric bottom plate, one end of the piezoelectric body is fixed to the base through the piezoelectric bottom plate, and the other end of the piezoelectric body is used to fix the connecting magnet, the connecting magnet is used to adsorb the magnetic friction foot, the pre-tightening magnet is fixed on the base, and repels the magnetic friction foot, and is used to press the magnetic friction foot onto the connecting magnet through the repulsive force; the piezoelectric body expands and contracts as the voltage at both ends changes, and drives the magnetic friction foot to move through the connecting magnet. The magnetic friction foot is in adsorption contact with the slider, and the slider is driven to move along its sliding direction through the friction force.

[0009] In a second aspect, the present invention proposes a driving method based on the above-mentioned durable three-axis driving mechanism, comprising:

[0010] If the current motion platform needs to move forward along the direction of its freedom, a sawtooth wave with a duty cycle of 90% to 100% is applied to both ends of the piezoelectric body of the motion platform as an excitation source; if the current motion platform needs to move backward along the direction of its freedom, a sawtooth wave with a duty cycle of 0% to 10% is applied to both ends of the piezoelectric body of the motion platform as an excitation source;

[0011] The three motion platforms cooperate with each other to realize the movement of the pipette of the minimally invasive cell puncture instrument in three directions of freedom.

[0012] In the third aspect, the present invention also proposes a minimally invasive cell puncture system, comprising a clamping pipette fixing bracket, an injection pipette and the above-mentioned durable three-axis drive mechanism, wherein the base of the X-degree of freedom motion table of the durable three-axis drive mechanism is fixed, the injection pipette fixing bracket is fixed on the loading plate of the Z-degree of freedom motion table of the durable three-axis drive mechanism, and the injection pipette is fixed at the end of the injection pipette fixing bracket.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] The durable three-axis minimally invasive cell puncture instrument drive mechanism proposed in the present invention can realize a function similar to the tool change cutting of machine tool tools, and the magnetic friction foot and pre-tightening magnet can be replaced arbitrarily to adapt to different performance requirements. When the magnetic friction foot is worn, the magnetic friction foot and the slider will always adapt to maintain a relatively constant and stable friction force due to the magnetic effect. The driver based on modular self-adsorption coupling design has the advantages of simple structure, strong wear resistance, wear adaptation, modular replacement, and no need for pre-tightening to prevent loosening, and has the potential to achieve durable drive.

[0015] The present invention is applied in a cell micromanipulation system. High-frequency excitation is applied during the artificial insemination cell puncture process. The piezoelectric inertial displacement jitter characteristics are utilized to control the displacement jitter amplitude ratio by adjusting the duty cycle, amplitude, and frequency ratio to achieve minimally invasive cell operation, which can effectively reduce cell damage. This method can also use a wider injection needle to deliver large volumes of editing materials, thereby improving targeting efficiency.

[0016] In addition, the developed puncture instrument driving mechanism can also be used in precision scientific instruments and medical devices such as scanning electron microscopes, micromanipulation systems, and total internal reflection fluorescence microscopy, and has great application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is an overall schematic diagram of the driving mechanism of the durable three-axis minimally invasive cell puncture instrument of the present invention;

[0018] Figure 2 It is a schematic structural diagram of an X-degree-of-freedom motion table in a driving mechanism of the present invention;

[0019] Figure 3 It is a schematic diagram of the structure of the Z-degree-of-freedom motion platform in the driving mechanism of the present invention;

[0020] Figure 4 It is a structural schematic diagram of the X-axis base in the driving mechanism of the present invention;

[0021] Figure 5 It is a structural schematic diagram of the Z-axis base in the driving mechanism of the present invention;

[0022] Figure 6 It is a schematic diagram of the structure of the X-axis carrier plate in the driving mechanism of the present invention;

[0023] Figure 7 It is a structural schematic diagram of a pre-tightening magnet limit plate in a driving mechanism of the present invention;

[0024] Figure 8 It is a structural schematic diagram of the stator assembly in the driving mechanism of the present invention;

[0025] Fig. 9 It is a structural schematic diagram of the pre-tightening magnet in the driving mechanism of the present invention;

[0026] Fig.10 It is a structural schematic diagram of the friction foot magnet in the driving mechanism of the present invention;

[0027] Fig.11 This is a working principle diagram of the driving mechanism of the durable three-axis minimally invasive cell puncture instrument of the present invention;

[0028] Fig.12 It is a schematic diagram of using the driving mechanism of the present invention to perform minimally invasive cell puncture. DETAILED DESCRIPTION

[0029] The present invention is further described and illustrated below in conjunction with specific embodiments. The embodiments are merely exemplary of the present disclosure and do not define the scope of limitation. The technical features of each embodiment of the present invention may be combined accordingly without conflicting with each other.

[0030] The driving foot and the slider of the traditional mechanism are in point-to-surface contact. After wear, the friction pair will produce a gap, resulting in driving failure. In the proposed modular magnetic self-adsorption coupling configuration, the slider is made of ferromagnetic material, and the driving foot, preload magnet, and link magnet are all made of unidirectionally magnetized rectangular magnetic steel. When wear occurs, the driving foot can always maintain a constant surface-to-surface contact with the slider under the action of magnetic attraction. According to the Archard model, the surface-to-surface contact mode has stronger wear resistance than the point-to-surface contact. The change in positive pressure caused by the wear of the magnetic driving foot is very weak. Simulation analysis shows that for a magnet with a size of 7×8×2 mm, when it is worn by 4 mm (reaching 1 / 2 of the total thickness of the magnet), the positive pressure still remains above 87% of the positive pressure when it is not worn. In addition, the developed driver can realize the function of tool change cutting similar to that of machine tool tools, and the magnetic friction foot and preload magnet can be replaced arbitrarily to adapt to different performance requirements. The drive based on magnetic self-adsorption modular design has the advantages of simple structure, strong wear resistance, wear self-adaptation, modular replacement, and no need for pre-tightening to prevent loosening, and has the potential to achieve durable drive.

[0031] The overall schematic diagram of the driving mechanism of the durable three-axis minimally invasive cell puncture instrument designed by the present invention is as follows: Figure 1 As shown, the durable three-axis minimally invasive cell manipulator mainly includes an X-degree-of-freedom motion table 1, a Y-degree-of-freedom motion table 2, and a Z-degree-of-freedom motion table 3. The three motion tables are connected in series to provide the puncture needle with movements in the X-axis direction, the Y-axis direction, and the Z-axis direction, respectively. The X-axis direction, the Y-axis direction, and the Z-axis direction are perpendicular to each other; the X-degree-of-freedom motion table 1 has a structure as shown in FIG. Figure 2As shown, it mainly includes an X-axis base 1-1, a loading plate 1-2, a grating sensor 1-3, a pre-tightening magnet limit plate 1-4, a stator assembly 1-5, a pre-tightening magnet 1-6, a magnetic friction foot 1-7, a link magnet 1-8 and a piezoelectric body 1-9; the Y-degree-of-freedom motion table 2 is completely identical in structure to the X-degree-of-freedom motion table 1, and the relative angle of the position is 90 degrees; the Z-degree-of-freedom motion table 3 is structured as shown in FIG. Figure 3 As shown, the difference from the X-DOF motion table 1 is that the Z-axis base 3-1 is different from the X-axis base 1-1 in structure, and the rest of the parts are consistent in structure and internal assembly of the motion table.

[0032] In the X-degree-of-freedom motion platform 1, the structural schematic diagram of the X-axis base 1-1 is as follows Figure 4 As shown, it consists of a base bottom plate 1-1-1, a base assembly through hole 1-1-2, a base assembly threaded hole 1-1-3, a magnet limit left plate 1-1-4, a magnet limit top plate 1-1-5, a limit plate mounting threaded hole 1-1-6, a pre-tightening magnet support surface 1-1-7, a driving magnet support surface 1-1-8, a driving magnet side baffle 1-1-9, a wiring hole 1-1-10, a piezoelectric bottom plate 1-1-11, a piezoelectric mounting groove 1-1-12, a piezoelectric avoidance groove 1-1-13, a sensor assembly groove 1-1-14, a base chamfer 1-1-15 and a sensor mounting threaded hole 1-1-16.

[0033] The schematic diagram of the structure of the base 3-1 of the Z-degree-of-freedom motion platform 3 is as follows Figure 5 As shown, the front end face structure is exactly the same as the base 1-1, and the rear end face structure is additionally provided with a base fixing plate 3-1-1, a base mounting hole 3-1-2, a base mounting countersunk hole 3-1-3 and a base reinforcing rib 3-1-4, which are used to fix the base 3-1 on the loading platform of the Y degree of freedom motion platform 2, so that the Z degree of freedom motion platform 3 and the Y degree of freedom motion platform 2 form a relative angle of 90 degrees.

[0034] Taking the X-DOF motion platform 1 as an example, the detailed configuration of a durable three-axis cell minimally invasive manipulator is described. The structure of the carrier plate 1-2 of the X-DOF motion platform 1 is as follows: Figure 6 As shown, it is composed of a carrier plate main board 1-2-1, a carrier plate countersunk hole 1-2-2, a carrier plate chamfer 1-2-3 and a carrier plate mounting threaded hole 1-2-4; the structure of the pre-tightening magnet limit plate 1-4 is as shown Figure 7 As shown, it includes a limit plate countersunk hole 1-4-1, a limit plate chamfer 1-4-2, a limit plate mounting hole 1-4-3, a limit plate positioning groove 1-4-4, a limit plate avoidance groove 1-4-5 and a pre-tightening magnet mounting groove 1-4-6; the structure of the stator assembly 1-5 is as shown Figure 8As shown, it includes a slider 1-5-1 and a fixed guide rail 1-5-2, and the materials of the slider 1-5-1 and the fixed guide rail 1-5-2 are ferromagnetic materials; the structures of the pre-tightening magnet 1-6 and the friction foot magnet 1-7 are respectively as shown in Fig. 9 and Fig.10 As shown, the link magnet 1-8 and the friction foot magnet 1-7 have the same structure, and the magnetic pole direction is also set in the same way, so that the link magnet 1-8 exerts an attractive force on the friction foot magnet 1-7;

[0035] A screw is used to pass through the through hole of the slider 1-5-1 and is screwed into the base assembly threaded hole 1-1-3 to fix the slider 1-5-1 on the base bottom plate 1-1-1; the slider 1-5-1 and the fixed guide rail 1-5-2 are matched with a groove, and the former can produce relative axial movement with respect to the latter; one end of the piezoelectric body 1-9 is fixed on the base 1-1 and fits in the piezoelectric body mounting groove 1-1-12, and the connecting magnet 1-8 is fixed to the other end of the piezoelectric body 1-9 by adhesive connection, and the magnetic friction foot 1-7 is adsorbed on the connecting magnet 1-8 through its own magnetism, and the connecting magnet 1-8 and the slider 1-5-1 are clearance fit, and the piezoelectric body 1-9 and the slider 1-5-1 are also clearance fit; the driving magnet support surface 1-1-8 limits the magnetic friction foot 1-7 and the connecting magnet 1-8, and the magnetic friction foot 1-7 is adsorbed on the slider 1-5-1, and there is friction between the two under the action of the magnetic adsorption force.

[0036] The pre-tightening magnet 1-6 is attached to the pre-tightening magnet supporting surface 1-1-7, and the magnet limiting left plate 1-1-4 and the magnet limiting top plate 1-1-5 limit the pre-tightening magnet 1-6. The screw passes through the limiting plate mounting hole 1-4-3 of the pre-tightening magnet limiting plate 1-4 and is screwed into the limiting plate mounting threaded hole 1-1-6 to fix the pre-tightening magnet 1-6 on the base 1-1, wherein the pre-tightening magnet mounting groove 1-4-6 is used to nest the pre-tightening magnet 1-6, and the limiting plate positioning groove 1-4-4 and the limiting plate avoidance groove 1-4-5 are respectively matched with the magnet limiting left plate 1-1-4 and the magnet limiting top plate 1-1-5; the specific configuration detailed structure is as follows Figure 2As shown, the magnetic friction foot 1-7, the linking magnet 1-8 and the pre-tightening magnet 1-6 are all single-pole magnetized, the N poles and S poles of the magnetic friction foot 1-7 and the linking magnet 1-8 are arranged alternately and attract each other, and the magnetic poles of the pre-tightening magnet 1-6 and the magnetic friction foot 1-7 are arranged in opposite directions, so that the pre-tightening magnet 1-6 and the magnetic friction foot 1-7 repel each other, so as to improve the response speed of the magnetic friction foot 1-7. The piezoelectric body 1-9 is made of piezoelectric material and can expand and contract as the voltage at both ends changes. In this embodiment, a d33 type piezoelectric stacked material with a pre-tightened shell is used, which has the characteristics of withstanding a certain shear force and tensile stress. The material stretches as the voltage at both ends increases, and shrinks vice versa. The reciprocating vibration of the magnetic friction foot 1-7 is controlled by applying an electrical signal to the piezoelectric body 1-9 through a wire, and the friction between the magnetic friction foot 1-7 and the slider 1-5-1 is controlled by the reciprocating vibration speed, thereby controlling the sliding of the slider 1-5-1; the magnet side baffle 1-1-9 is driven to perform dust-proof packaging for the entire machine, and the wire used to apply an electrical signal to the piezoelectric body 1-9 is discharged through the wiring hole 1-1-10. The grating sensor 1-3 is assembled into the sensor assembly slot 1-1-14, and the screw passes through the grating sensor 1-3 and is screwed into the sensor mounting threaded hole 1-1-16 to fix it on the base 1-1. The grating sensor 1-3 can detect the position of the slider 1-5-1 in real time, thereby providing feedback data for the motion control of the drive mechanism. The screw passes through the countersunk hole 1-2-2 of the carrier plate to fix the carrier plate 1-2 on the slider 1-5-1.

[0037] The bases of the Y-degree-of-freedom motion table and the Z-degree-of-freedom motion table are both provided with an X-axis base assembly through hole 1-1-2 such as the X-axis base 1-1 and a carrier plate mounting threaded hole 1-2-4 such as the X-axis carrier plate 1-2; screws pass through the Y-axis base assembly through hole and the carrier plate mounting threaded hole 1-2-4 to fix the Y-degree-of-freedom motion table on the X-degree-of-freedom motion table, screws pass through the Z-axis base mounting hole 3-1-2 and are screwed into the carrier plate of the Y-degree-of-freedom motion table to fix the Z-degree-of-freedom motion table on the Y-degree-of-freedom motion table, the linking magnet 1-8, the pre-tightening magnet 1-6 and the magnetic friction foot 1-7 are single-stage magnetized magnets, and except that the material of the slider 1-5-1 is ferromagnetic material (such as high carbon steel), the other components are all non-ferromagnetic materials (such as AL7075, etc.).

[0038] In the present invention, the X-degree-of-freedom motion platform, the Y-degree-of-freedom motion platform and the Z-degree-of-freedom motion platform are connected in series in structure to realize the motion in the three-axis directions of X, Y and Z. The working principle of the durable three-axis drive mechanism of the present invention is as follows: Fig.11 For each motion platform, when moving forward, Fig.11As shown in part (a), a sawtooth wave with a duty cycle of 90% to 100% (not including 100%) is applied to both ends of the piezoelectric body 1-9 as an excitation source, and one cycle of the sawtooth wave is divided into the period t0 to t1 and the period t1 to t2. During the period t0 to t1, the moving platform is in the sticking stage, and the piezoelectric body 1-9 slowly stretches as the voltage at both ends increases; the linking magnet 1-8 is fixedly connected to the piezoelectric body 1-9, so as the piezoelectric body slowly stretches, the magnetic friction foot 1-7 moves forward under the attraction of the linking magnet 1-8 and the repulsion of the pre-tightening magnet 1-6. Due to the lower stretching speed of the piezoelectric body 1-9 at this time, there is static friction between the magnetic friction foot 1-7 and the slider 1-5-1. Under the static friction force f s Under the action, the slider 1-5-1 moves forward D f During the period of t1 to t2, the moving platform is in the sliding stage. The piezoelectricity at both ends of the piezoelectric body 1-9 decreases rapidly, the piezoelectric body 1-9 contracts rapidly, and the magnetic friction foot 1-7 moves rapidly in the opposite direction under the attraction of the link magnet 1-8 and the repulsion of the pre-tightening magnet 1-6. Since the piezoelectric body 1-9 contracts rapidly, there is a dynamic friction force between the magnetic friction foot 1-7 and the slider 1-5-1. The slider 1-5-1 first produces a deceleration motion. When the inertia force of the slider 1-5-1 is difficult to overcome the friction force f in the sliding stage, the slider 1-5-1 moves in the opposite direction. d When the displacement is reversed, D b , a net displacement D is generated in a single cycle net = D f -D b . For reverse motion, a 0%~10% (not including 0%) sawtooth wave is used as the excitation source. The operation process is opposite to that of the forward motion. Fig.11 The unique advantage of the present invention is that when the magnetic friction foot 1-7 is worn, the magnetic friction foot 1-7 and the ferromagnetic slider 1-5-1 will always adaptively maintain a relatively constant and stable friction force, and the bending stress value of the piezoelectric body can still always remain at a small value after the magnetic friction foot 1-7 is worn.

[0039] Based on the above-mentioned durable three-axis drive mechanism, the present invention also provides a minimally invasive cell puncture instrument, which includes a clamping pipette fixing bracket, an injection pipette and a durable three-axis drive mechanism, wherein the base of the X-degree-of-freedom motion table of the durable three-axis drive mechanism is fixed on the cell micromanipulation table, the injection pipette fixing bracket is fixed on the sample plate of the Z-degree-of-freedom motion table of the durable three-axis drive mechanism, and the injection pipette is fixed to the end of the injection pipette fixing bracket. The cells to be punctured are adsorbed on the end of the clamping micropipette. The durable three-axis drive mechanism is based on the inertial drive principle, and the displacement vibration can be controlled by adjusting the amplitude, frequency and duty cycle of the excitation source. Although this feature has traditionally been regarded as a disadvantage due to its impact on position tracking accuracy, the present invention utilizes this function for the first time to achieve minimally invasive cell manipulation using only a single drive core.

[0040] like Fig.12 As shown in the embodiment, a comparative test was conducted on the excitation puncture realized by the mechanism of the present invention and the traditional puncture without excitation. The test results show that by adjusting the duty cycle and amplitude frequency of the excitation source at both ends of the piezoelectric body, minimally invasive cell puncture can be achieved. The cell deformation amount is different when there is excitation puncture or not. Fig.12 Part (a) of the paper shows that the relationship between the duty cycle of the excitation source and the displacement of the slider is Fig.12 Part (b) is given; the excitation puncture was performed at 100 Hz, 5% duty cycle, and the non-excitation puncture was performed at 10 Hz, 0% duty cycle. The voltage was 100 Vp-p. When there was no excitation puncture, the cells underwent a great deformation, but the zona pellucida of the cells was still not punctured. Through the excitation puncture, minimally invasive puncture was achieved.

[0041] In addition to being used in minimally invasive cell puncture instruments, the present invention also has great application prospects in precision scientific instruments and medical devices such as scanning electron microscopes, micromanipulation systems, and total internal reflection fluorescence microscopy.

[0042] The above-mentioned embodiments only express several implementation methods of the present invention, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. For ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A durable three-axis drive mechanism for a minimally invasive cell puncture instrument, characterized in that: Including X-degree of freedom motion table, Y-degree of freedom motion table and Z-degree of freedom motion table; The X-degree-of-freedom motion table, the Y-degree-of-freedom motion table, and the Z-degree-of-freedom motion table all include a base, on which a stator assembly, a pre-tightening magnet, a magnetic friction foot, and a link magnet and a piezoelectric body are installed; the stator assembly consists of a slide rail and a slider, the slide rail is fixed on the base, and the slider forms a sliding fit with the slide rail, and the sliding direction of the slider of each motion table is the direction of its degree of freedom, and a carrier plate is fixed on the slider, and the carrier plate is used to install the substrate of other motion tables or the pipette of the cell minimally invasive puncture instrument; The base is provided with a piezoelectric body bottom plate, one end of the piezoelectric body is fixed to the base through the piezoelectric body bottom plate, and the other end of the piezoelectric body is used to fix the linking magnet, the linking magnet is used to adsorb the magnetic friction foot, the pre-tightening magnet is fixed on the base, and repels the magnetic friction foot, and is used to press the magnetic friction foot onto the linking magnet through repulsion; the piezoelectric body expands and contracts with the voltage at both ends, and drives the magnetic friction foot to move through the linking magnet, the magnetic friction foot is in adsorption contact with the slider, and the slider is driven to move along its sliding direction through friction; An excitation source is applied to both ends of the piezoelectric body, and the excitation source is a sawtooth wave; the linking magnet and the piezoelectric body form a gap fit with the slider respectively; the material of the slider is ferromagnetic material, and except for the slider, linking magnet, pre-tightening magnet and magnetic friction, other parts of the driving mechanism are all non-ferromagnetic materials.

2. The durable three-axis drive mechanism according to claim 1, characterized in that: A grating sensor is also installed on the base, and the grating sensor is used to detect the position of the slider in real time.

3. The durable three-axis drive mechanism according to claim 1, characterized in that: The piezoelectric body and the link magnet are connected by adhesive.

4. The durable three-axis drive mechanism according to claim 1, characterized in that: The base is provided with a piezoelectric body bottom plate, the piezoelectric body bottom plate is provided with a piezoelectric body installation groove, one end of the piezoelectric body is fixed in the piezoelectric body installation groove, and the side surface of the piezoelectric body does not fit the base.

5. The durable three-axis drive mechanism according to claim 1, characterized in that: The base is provided with a driving magnet side baffle for realizing dust-proof packaging of the sports table.

6. A driving method based on the durable three-axis driving mechanism according to claim 1, characterized in that: The method comprises: If the current motion platform needs to move forward along the direction of its degree of freedom, a sawtooth wave with a duty cycle of 90% to 100% is applied to both ends of the piezoelectric body of the motion platform as an excitation source; during the voltage increase stage within one cycle of the sawtooth wave, the piezoelectric body stretches, and the magnetic friction foot drives the slider to move forward by static friction D f ; During the voltage reduction stage within one cycle of the sawtooth wave, the piezoelectric body shortens, and the magnetic friction foot drives the slider to decelerate first and then move in the opposite direction through dynamic friction D b Since the static friction is greater than the dynamic friction, the slider achieves a positive displacement D in one cycle. net = D f -D b ; If the current motion platform needs to move in the opposite direction along its degree of freedom, a sawtooth wave with a duty cycle of 0% to 10% is applied to both ends of the piezoelectric body of the motion platform as an excitation source; during the voltage increase stage within one cycle of the sawtooth wave, the piezoelectric body stretches, and the magnetic friction foot drives the slider to move forward D' through the dynamic friction force b ; During the voltage reduction stage within one cycle of the sawtooth wave, the piezoelectric body shortens, and the magnetic friction foot drives the slider to decelerate first and then reverse displacement D' through static friction f , the slider achieves reverse displacement D' in one cycle net = D' f -D' b ; The three motion platforms cooperate with each other to realize the movement of the pipette of the minimally invasive cell puncture instrument in three directions of freedom.

7. A minimally invasive cell puncture system, characterized in that: It comprises a clamping pipette fixing bracket, an injection pipette and the durable three-axis driving mechanism as described in claim 1, wherein the base of the X-degree-of-freedom motion table of the durable three-axis driving mechanism is fixed, the injection pipette fixing bracket is fixed on the loading plate of the Z-degree-of-freedom motion table of the durable three-axis driving mechanism, and the injection pipette is fixed on the end of the injection pipette fixing bracket.

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