CN107147328B - It is bent the two-freedom piezoelectric actuator of piezoelectric vibrator and the motivational techniques for the two-freedom movement realized using the driver - Google Patents

Abstract

A two-degree-of-freedom piezoelectric driver for a bending piezoelectric vibrator and an excitation method for two-degree-of-freedom motion realized by the driver. The utility model belongs to the field of piezoelectric drive technology. The problem of complex structure, high cost and small stroke of the existing two-degree-of-freedom piezoelectric driving device is solved. The driver includes a base, a piezoelectric vibrator and a mover. The curved piezoelectric ceramic component is divided into two parts, namely the first group of curved piezoelectric ceramic group and the second group of curved piezoelectric ceramic group, and the two groups of curved piezoelectric ceramic When the voltage excitation signal is applied, the piezoelectric vibrator can realize the bending motion of two degrees of freedom respectively. By changing the voltage excitation signal, the bending direction of the piezoelectric vibrator can be controlled; the friction force is used as the driving force, and the piezoelectric vibrator is used as the stator to drive the mover to realize two-degree-of-freedom motion. The invention is mainly applied in the fields of ultra-precision driving, positioning, processing and the like.

Description

A two-degree-of-freedom piezoelectric driver of a bending piezoelectric vibrator and a device realized by using the driver Excitation method for two-degree-of-freedom motion

technical field

The invention belongs to the field of piezoelectric drive technology.

Background technique

In recent years, piezoelectric drive technology, as a new type of drive technology, has been widely used in ultra-precision machining, positioning and other fields, and has been greatly developed. Piezoelectric drive technology is a drive technology that uses the inverse piezoelectric effect of piezoelectric materials to convert electrical energy into mechanical energy. Piezoelectric actuators have the advantages of simple structure, high precision, high power density, large output force, no electromagnetic interference, and easy miniaturization. They have been widely used in ultra-precision fields such as aerospace, robotics, and nano-manufacturing. Two-degree-of-freedom piezoelectric actuators, which can realize multiple driving functions with a single actuator, can effectively reduce the size of the actuator, and have received more and more attention. The existing two-degree-of-freedom piezoelectric actuators mainly use the single-degree-of-freedom piezoelectric actuators driven by piezoelectric stacks to be connected in parallel or in series to realize two-degree-of-freedom drives. , resulting in too small a stroke; the use of a series driver can effectively expand the stroke, but the accuracy is lost. At the same time, the price of the piezoelectric stack is very expensive, which greatly affects the application of the two-degree-of-freedom piezoelectric driver.

The excitation method of the two-degree-of-freedom piezoelectric driver using the bending piezoelectric vibrator of the present invention controls the two-degree-of-freedom driving of the driver. Compared with the piezoelectric stack, the cost is greatly reduced. Driven by the friction force, expanding its stroke. At the same time, the driven mover can be a plane, used to realize two-degree-of-freedom movement; the mover can also be cylindrical, used to realize one-degree-of-freedom movement and one-degree-of-freedom rotation; the mover can also be spherical, It is used to realize the rotation of two degrees of freedom. Due to the diversity of the shape of the mover, the application range of the two-degree-of-freedom piezoelectric actuator is greatly expanded, and it has a good application prospect.

Contents of the invention

The invention aims to solve the problems of complex structure, high cost and small stroke of the existing two-degree-of-freedom piezoelectric driving device. The invention provides a two-degree-of-freedom piezoelectric driver for a bending piezoelectric vibrator and an excitation method for two-degree-of-freedom motion realized by the driver.

A two-degree-of-freedom piezoelectric driver for a bent piezoelectric vibrator, which includes a base, a piezoelectric vibrator and a mover;

The piezoelectric vibrator includes a curved piezoelectric ceramic group, a horn and a driving foot, the curved piezoelectric ceramic group is arranged between the base and the horn, the thin end of the horn is provided with a driving foot, and the driving foot is in contact with the mover ;

The curved piezoelectric ceramic group is divided into two parts, namely the first group of curved piezoelectric ceramic group and the second group of curved piezoelectric ceramic group.

An energized electrode sheet is provided between two adjacent piezoelectric ceramic sheets in the first curved piezoelectric ceramic group and the second curved piezoelectric ceramic group.

Using the two-degree-of-freedom motion excitation method realized by the two-degree-of-freedom piezoelectric driver of the bending piezoelectric vibrator, the two-degree-of-freedom motion excitation method can drive the mover to move along the X-axis and the Y-axis in two two-degree-of-freedom motions, The specific performance is: drive the mover to move in the positive or negative direction along the X axis, and move in the positive or negative direction along the Y axis;

Wherein, the directions pointed by the X-axis and the Y-axis are two mutually perpendicular directions in the radial plane of the curved piezoelectric vibrator, and the directions pointed by both are positive;

(1) The specific process of driving the mover to move forward along the X axis is as follows:

Step 11: Apply an excitation voltage signal with a gradually increasing amplitude to the first group of curved piezoelectric ceramic groups. The rise time is t1. The piezoelectric vibrator is bent and deformed to the limit position along the positive direction of the X-axis. Under the action of static friction, through The driving foot drives the mover to generate displacement output along the positive direction of the X axis;

Step 12: Apply an excitation voltage signal with a gradually decreasing amplitude to the first group of curved piezoelectric ceramic groups, the falling time is t2, and t2<<t1, the piezoelectric vibrator produces a bending deformation along the negative direction of the X-axis to the initial position, The mover remains stationary due to inertia;

Step 13. Repeat steps 11 to 12 to realize the continuous motion output of the mover along the positive direction of the X axis;

(2) The specific process of driving the mover to move along the negative direction of the X axis is:

Step 21: Apply an excitation voltage signal with a gradually decreasing amplitude to the first group of curved piezoelectric ceramic groups. The falling time is t1. The piezoelectric vibrator is bent and deformed to the limit position along the negative direction of the X axis. Under the action of static friction, it passes The driving foot drives the mover to generate displacement output along the negative direction of the X axis;

Step 22: Apply an excitation voltage signal with a gradually increasing amplitude to the first group of curved piezoelectric ceramic groups, the rise time is t2, and t2<<t1, the piezoelectric vibrator produces a bending deformation along the positive direction of the X-axis to the initial position, The mover remains stationary due to inertia;

Step 23, repeating step 21 to step 22, the continuous motion output of the mover along the negative direction of the X axis can be realized;

(3) The specific process of driving the mover to move forward along the Y axis is as follows:

Step 31. Apply an excitation voltage signal with a gradually increasing amplitude to the second group of curved piezoelectric ceramic groups. The rise time is t1. The piezoelectric vibrator is bent and deformed to the limit position along the positive direction of the Y axis. Under the action of static friction, through The driving foot drives the mover to generate displacement output along the positive direction of the Y axis;

Step 32: Apply a voltage excitation signal with a gradually decreasing amplitude to the second group of bending piezoelectric ceramic groups, the falling time is t2, and t2<<t1, the piezoelectric vibrator produces a bending deformation along the negative direction of the Y-axis to the initial position, The mover remains stationary due to inertia;

Step 33, repeating step 31 to step 32, can realize the continuous motion output of the mover along the positive direction of the Y axis;

(4) The specific process of driving the mover to move along the negative direction of the Y axis is:

Step 41. Apply an excitation voltage signal with a gradually decreasing amplitude to the second group of curved piezoelectric ceramic groups. The falling time is t1. The piezoelectric vibrator is bent and deformed to the limit position along the negative direction of the Y axis. Under the action of static friction, through The driving foot drives the mover to generate displacement output along the negative direction of the Y axis;

Step 42: Apply an excitation voltage signal with a gradually increasing amplitude to the second group of curved piezoelectric ceramic groups, the falling time is t2, and t2<<t1, the piezoelectric vibrator produces a bending deformation along the positive direction of the Y-axis to the initial position, The mover remains stationary due to inertia;

Step 43. Repeat steps 41 to 42 to realize the continuous motion output of the mover along the negative direction of the Y-axis.

A two-degree-of-freedom motion excitation method is realized by using a two-degree-of-freedom piezoelectric driver of a bending piezoelectric vibrator. In this method, the waveform of the applied voltage excitation signal is an asymmetrical triangular wave or an asymmetrical trapezoidal wave.

The mover is a cylindrical mover, a spherical mover or a planar mover.

When the mover is a planar mover, the drive mover moves in the positive or negative direction along the X-axis, and moves in the positive or negative direction along the Y-axis. The mover moves positively or negatively along the X-axis, and positively or negatively along the Y-axis.

When the mover is a cylindrical mover, drive the mover to move in the positive or negative direction along the X-axis, and move in the positive or negative direction along the Y-axis. direction movement, and two-degree-of-freedom motion that rotates clockwise or counterclockwise around the X-axis.

When the mover is a spherical mover, the mover is driven to move in the positive or negative direction along the X axis, and to move in the positive or negative direction along the Y axis. The specific performance is: drive the mover clockwise or counterclockwise around the X axis Clockwise rotation, and two degrees of freedom motion with clockwise or counterclockwise rotation about the Y axis.

The beneficial effect brought by the present invention is that the present invention provides a two-degree-of-freedom piezoelectric driver for bending a piezoelectric vibrator and an excitation method for two-degree-of-freedom motion realized by using the driver. During work, the drive in two directions can be realized. , can be combined to achieve a variety of functions. The two-degree-of-freedom piezoelectric driver adopting the bending piezoelectric vibrator of the present invention has low cost and large driving stroke. At the same time, the mover structure can be in the shape of a plane, a cylinder, a ball, etc., and the driving objects are diversified and have a wide range of applications.

In the specific working process, by controlling the amplitude of the applied excitation voltage, the precise adjustment of the single step of the mover can be realized; by controlling the frequency of the applied excitation voltage, the precise control of the moving speed of the mover can be realized. It has broad application prospects in ultra-precision driving, positioning, processing and other fields.

Description of drawings

Fig. 1 is a main cross-sectional view of a two-degree-of-freedom piezoelectric driver of a curved piezoelectric vibrator when the mover is a planar mover;

Fig. 2 is a schematic diagram of a three-dimensional structure of a bending piezoelectric vibrator;

3 is a schematic diagram of a three-dimensional structure of a two-degree-of-freedom piezoelectric driver of a curved piezoelectric vibrator when the mover is a planar mover;

Fig. 4 is a three-dimensional structural schematic diagram of a two-degree-of-freedom piezoelectric driver of a bending piezoelectric vibrator when the mover is a cylindrical mover;

Fig. 5 is a three-dimensional structural schematic diagram of a two-degree-of-freedom piezoelectric driver of a curved piezoelectric vibrator when the mover is a spherical mover;

Figure 6 is a waveform diagram of the excitation voltage signal applied when the planar mover moves in the positive direction along the X-axis; where, V _max is the maximum value of the positive voltage amplitude, and -V _max is the maximum value of the negative voltage amplitude Maximum value, T ₀ is the initial time, T is the period;

Fig. 7 and Fig. 8 are under the condition of the excitation voltage signal applied in Fig. 6, the state diagram of the planar mover moving along the X axis in the positive direction;

Figure 9 is a waveform diagram of the excitation voltage signal applied when the planar mover moves in the negative direction along the X-axis; where, V _max is the maximum value of the positive voltage amplitude, and -V _max is the maximum value of the negative voltage amplitude Maximum value, T ₀ is the initial time, T is the cycle; Figure 10 and Figure 11 are under the condition of the excitation voltage signal applied in Figure 9, the state diagram of the planar mover moving along the negative direction of the X axis;

Figure 12 is a waveform diagram of the excitation voltage signal applied when the planar mover moves in the positive direction along the Y axis; where, V _max is the maximum value of the positive voltage amplitude, and -V _max is the maximum value of the negative voltage amplitude Maximum value, T ₀ is the initial time, T is the period;

Fig. 13 and Fig. 14 are under the conditions of the excitation voltage signal applied in Fig. 12, the state diagram of the planar mover moving in the positive direction along the Y axis;

Figure 15 is a waveform diagram of the excitation voltage signal applied when the planar mover moves in the negative direction along the Y axis; where, V _max is the maximum value of the positive voltage amplitude, and -V _max is the maximum value of the negative voltage amplitude Maximum value, T ₀ is the initial time, T is the period;

FIG. 16 and FIG. 17 are state diagrams of the planar mover moving in the negative direction of the Y-axis under the condition of the excitation voltage signal applied in FIG. 15 .

Detailed ways

Specific Embodiment 1: Refer to FIG. 1 to FIG. 5 to illustrate this embodiment. The two-degree-of-freedom piezoelectric driver for a bending piezoelectric vibrator described in this embodiment includes a base 1 , a piezoelectric vibrator 2 and a mover 3 ;

The piezoelectric vibrator 2 includes a curved piezoelectric ceramic group 2-1, a horn 2-2 and a driving foot 2-3, and the curved piezoelectric ceramic group 2-1 is arranged between the base 1 and the horn 2-2 Between, the thin end of the horn 2-2 is provided with a driving foot 2-3, and the driving foot 2-3 is in contact with the mover 3;

The curved piezoelectric ceramic group 2-1 is divided into two parts, namely the first curved piezoelectric ceramic group 2-1-1 and the second curved piezoelectric ceramic group 2-1-2.

In this embodiment, the two-degree-of-freedom piezoelectric driver using the bending piezoelectric vibrator of the present invention has low cost and large driving stroke. In the specific working process, by controlling the amplitude of the excitation voltage applied to the bending piezoelectric ceramic group 2-1, the precise adjustment of the single step of the mover can be realized; by controlling the excitation voltage applied to the bending piezoelectric ceramic group 2-1 The frequency can realize the precise control of the movement speed of the mover.

Specific Embodiment 2: Refer to Fig. 1 to Fig. 5 to illustrate this embodiment. The difference between this embodiment and the two-degree-of-freedom piezoelectric actuator for the bending piezoelectric vibrator described in Embodiment 1 is that the mover 3 is a tube Type mover, spherical mover or planar mover.

Specific Embodiment 3: Refer to FIG. 1 to FIG. 5 to illustrate this embodiment. The difference between this embodiment and the two-degree-of-freedom piezoelectric actuator for the bending piezoelectric vibrator described in Embodiment 1 is that the first group of bending piezoelectric vibrators An electrified electrode sheet 2-4 is provided between two adjacent piezoelectric ceramic sheets in the electric ceramic group 2-1-1 and the second group of curved piezoelectric ceramic groups 2-1-2.

Specific Embodiment 4: Refer to Fig. 1 to Fig. 5 to illustrate this embodiment, using the two-degree-of-freedom motion excitation method realized by the two-degree-of-freedom piezoelectric driver of the bending piezoelectric vibrator described in specific embodiment 1, the two-degree-of-freedom motion The excitation method can drive the mover 3 to move along the two degrees of freedom of the X axis and the Y axis, specifically: drive the mover 3 to move in the positive or negative direction along the X axis, and move in the positive or negative direction along the Y axis;

Wherein, the directions pointed by the X-axis and the Y-axis are two mutually perpendicular directions in the radial plane of the curved piezoelectric vibrator, and the directions pointed by both are positive;

(1) The specific process of driving the mover 3 to move forward along the X axis is as follows:

Step 11: Apply an excitation voltage signal with gradually increasing amplitude to the first group of curved piezoelectric ceramic groups 2-1-1, the rise time is t1, and the piezoelectric vibrator 2 is bent and deformed to the limit position along the positive direction of the X-axis. Under the action of static friction, the mover 3 is driven by the driving foot 2-3 to generate displacement output along the positive direction of the X axis;

Step 12: Apply an excitation voltage signal with a gradually decreasing amplitude to the first group of curved piezoelectric ceramic groups 2-1-1, the falling time is t2, and t2<<t1, the piezoelectric vibrator 2 generates a negative direction along the X-axis Bending and deforming to the initial position, the mover 3 remains stationary due to inertia;

Step 13, repeat step 11 to step 12, can realize the continuous motion output of mover 3 along the positive direction of X axis;

(2) The specific process of driving the mover 3 to move in the negative direction of the X-axis is as follows:

Step 21: Apply an excitation voltage signal with a gradually decreasing amplitude to the first group of curved piezoelectric ceramic groups 2-1-1, the falling time is t1, and the piezoelectric vibrator 2 bends and deforms to the limit position along the negative direction of the X-axis. Under the action of static friction, the mover 3 is driven by the driving foot 2-3 to generate displacement output along the negative direction of the X axis;

Step 22: Apply an excitation voltage signal with a gradually increasing amplitude to the first group of curved piezoelectric ceramic groups 2-1-1, the rise time is t2, and t2<<t1, the piezoelectric vibrator 2 generates positive vibration along the X-axis Bending and deforming to the initial position, the mover 3 remains stationary due to inertia;

Step 23, repeat step 21 to step 22, the continuous motion output of the mover 3 along the negative direction of the X axis can be realized;

(3) The specific process of driving the mover 3 to move forward along the Y axis is as follows:

Step 31: Apply an excitation voltage signal with a gradually increasing amplitude to the second group of curved piezoelectric ceramic groups 2-1-2, the rise time is t1, and the piezoelectric vibrator 2 is bent and deformed to the limit position along the positive direction of the Y-axis. Under the action of static friction, the mover 3 is driven by the driving foot 2-3 to generate displacement output along the positive direction of the Y axis;

Step 32: Apply a voltage excitation signal with a gradually decreasing amplitude to the second group of curved piezoelectric ceramic groups 2-1-2, the falling time is t2, and t2<<t1, the piezoelectric vibrator 2 generates negative vibration along the Y axis Bending and deforming to the initial position, the mover 3 remains stationary due to inertia;

Step 33, repeating step 31 to step 32, can realize the continuous motion output of mover 3 along the positive direction of Y axis;

(4) The specific process of driving the mover 3 to move in the negative direction along the Y axis is as follows:

Step 41: Apply an excitation voltage signal with a gradually decreasing amplitude to the second group of curved piezoelectric ceramic groups 2-1-2, and the falling time is t1, and the piezoelectric vibrator 2 is bent and deformed to the limit position along the negative direction of the Y axis. Under the action of static friction, the mover 3 is driven by the driving foot 2-3 to generate displacement output along the negative direction of the Y axis;

Step 42: Apply an excitation voltage signal with a gradually increasing amplitude to the second group of curved piezoelectric ceramic groups 2-1-2, the falling time is t2, and t2<<t1, the piezoelectric vibrator 2 generates positive vibration along the Y axis Bending and deforming to the initial position, the mover 3 remains stationary due to inertia;

Step 43, repeating Step 41 to Step 42, the continuous motion output of the mover 3 along the negative direction of the Y-axis can be realized.

In this embodiment, the displacement generated by the mover 3 in step 11, step 21, step 31 and step 41 is very small.

Specific Embodiment 5: Referring to Fig. 1 to Fig. 5 to illustrate this embodiment, the difference between this embodiment and the excitation method of two-degree-of-freedom motion realized by a two-degree-of-freedom piezoelectric driver using a bending piezoelectric vibrator described in Embodiment 4 That is, the mover 3 is a cylindrical mover, a ball mover or a planar mover.

Specific Embodiment 6: Referring to Fig. 1 to Fig. 5 to illustrate this embodiment, the difference between this embodiment and the excitation method of two-degree-of-freedom motion realized by a two-degree-of-freedom piezoelectric driver using a bending piezoelectric vibrator described in Embodiment 4 In this method, the waveform of the voltage excitation signal applied is an asymmetrical triangular wave or an asymmetrical trapezoidal wave.

Specific embodiment 7: Referring to Fig. 1 to Fig. 5 to illustrate this embodiment, the difference between this embodiment and the excitation method of two-degree-of-freedom motion realized by a two-degree-of-freedom piezoelectric driver using a bending piezoelectric vibrator described in Embodiment 5 That is, when the mover 3 is a planar mover, the mover 3 is driven to move positively or negatively along the X-axis, and to move positively or negatively along the Y-axis. Specifically, in the plane where the planar mover is located , to drive the planar mover to move positively or negatively along the X-axis, and to move positively or negatively along the Y-axis.

In this embodiment, the specific process of the planar mover moving in the positive direction along the X-axis will be described in conjunction with Figures 6 to 8, wherein Figure 7 and Figure 8 correspond to Step 11 and Step 12 respectively; Step 1 Among them, the first group of curved piezoelectric ceramics group 2-1-1 applies an excitation voltage signal with a slowly rising amplitude, which corresponds to the t1 segment of the voltage excitation signal in Figure 7. In steps 1 and 2, the first group of curved piezoelectric ceramics group 2 The amplitude of the excitation voltage signal applied by -1-1 drops rapidly, corresponding to the t2 segment of the voltage excitation signal in Figure 8.

The specific process for the planar mover to move in the negative direction along the X-axis is illustrated in conjunction with Figures 9 to 11, wherein Figure 10 and Figure 11 correspond to Step 21 and Step 22 respectively; in Step 21, the first group The bending piezoelectric ceramic group 2-1-1 applies an excitation voltage signal whose amplitude decreases slowly, corresponding to the t1 segment of the voltage excitation signal in Figure 10; in step 22, the first group of bending piezoelectric ceramic group 2-1-1 The amplitude of the applied excitation voltage signal rises rapidly, corresponding to the t2 segment of the voltage excitation signal in FIG. 11 .

The specific process of the planar mover realizing positive movement along the Y-axis will be described in conjunction with Figures 12 to 14, wherein Figure 13 and Figure 14 correspond to Step 31 and Step 32 respectively; in Step 31, the second group The bending piezoelectric ceramic group 2-1-2 applies an excitation voltage signal with a slowly rising amplitude, which corresponds to the t1 section of the voltage excitation signal in Figure 13; in step 32, the second group of bending piezoelectric ceramic group 2-1-2 The amplitude of the applied excitation voltage signal drops rapidly, corresponding to the t2 segment of the voltage excitation signal in FIG. 14 .

The specific process for the planar mover to move in the negative direction along the Y axis will be described in conjunction with Figures 15 to 17, wherein Figure 16 and Figure 17 correspond to Step 41 and Step 42 respectively; in Step 41, the second group The bending piezoelectric ceramic group 2-1-2 applies an excitation voltage signal whose amplitude decreases slowly, corresponding to the t1 segment of the voltage excitation signal in Figure 16; in step 42, the second group of bending piezoelectric ceramic group 2-1-2 The amplitude of the applied excitation voltage signal drops rapidly, corresponding to the t2 segment of the voltage excitation signal in FIG. 17 .

Embodiment 8: Refer to Fig. 1 to Fig. 5 to illustrate this embodiment, the difference between this embodiment and the excitation method of two-degree-of-freedom motion realized by a two-degree-of-freedom piezoelectric driver using a bending piezoelectric vibrator described in Embodiment 5 That is, when the mover 3 is a cylindrical mover, the drive mover 3 moves positively or negatively along the X-axis, and moves positively or negatively along the Y-axis. Positive or negative movement, and two degrees of freedom of movement clockwise or counterclockwise about the X-axis.

Specific embodiment nine: Refer to Fig. 1 to Fig. 5 to illustrate this embodiment, the difference between this embodiment and the excitation method of two-degree-of-freedom motion realized by the two-degree-of-freedom piezoelectric driver using the bending piezoelectric vibrator described in the fifth embodiment That is, when the mover 3 is a spherical mover, the mover 3 is driven to move positively or negatively along the X-axis, and to move positively or negatively along the Y-axis. Clockwise or counterclockwise rotation, and two degrees of freedom motion with clockwise or counterclockwise rotation about the Y axis.

Claims (7)

1. The two-degree-of-freedom motion excitation method realized by the two-degree-of-freedom piezoelectric driver of the bending piezoelectric vibrator. The two-degree-of-freedom piezoelectric driver of the bending piezoelectric vibrator includes a base (1), a piezoelectric vibrator (2) and a dynamic child(3); The piezoelectric vibrator (2) includes a curved piezoelectric ceramic group (2-1), a horn (2-2) and a driving foot (2-3), and the curved piezoelectric ceramic group (2-1) is arranged on the base Between the seat (1) and the horn (2-2), the thin end of the horn (2-2) is provided with a driving foot (2-3), and the driving foot (2-3) is in contact with the mover (3); The curved piezoelectric ceramic group (2-1) is divided into two parts, respectively the first group of curved piezoelectric ceramic group (2-1-1) and the second group of curved piezoelectric ceramic group (2-1-2) ; It is characterized in that the excitation method of the two-degree-of-freedom motion can drive the mover (3) to move along the X-axis and the Y-axis with two two-degree-of-freedom movements, specifically: driving the mover (3) to move along the X-axis in a positive or negative direction , and positive or negative movement along the Y axis; Wherein, the directions pointed by the X-axis and the Y-axis are two mutually perpendicular directions in the radial plane of the curved piezoelectric vibrator, and the directions pointed by both are positive; (1) The specific process of driving the mover (3) to move forward along the X axis is as follows: Step 11: Apply an excitation voltage signal with a gradually increasing amplitude to the first group of curved piezoelectric ceramic groups (2-1-1), the rise time is t1, and the piezoelectric vibrator (2) produces bending deformation along the positive direction of the X-axis to At the extreme position, under the action of static friction, the mover (3) is driven by the driving foot (2-3) to generate displacement output along the positive direction of the X-axis; Step 12: Apply an excitation voltage signal with a gradually decreasing amplitude to the first group of curved piezoelectric ceramic groups (2-1-1), the falling time is t2, and t2<<t1, the piezoelectric vibrator (2) generates an edge along X The shaft is bent and deformed to the initial position in the negative direction, and the mover (3) remains stationary due to inertia; Step 13, repeat step 11 to step 12, can realize the continuous motion output of mover (3) along the positive direction of X axis; (2) The specific process of driving the mover (3) to move in the negative direction along the X axis is: Step 21: Apply an excitation voltage signal with a gradually decreasing amplitude to the first group of curved piezoelectric ceramic groups (2-1-1), the falling time is t1, and the piezoelectric vibrator (2) produces bending deformation along the negative direction of the X-axis to At the limit position, under the action of static friction, the mover (3) is driven by the driving foot (2-3) to generate displacement output along the negative direction of the X-axis; Step 22: Apply an excitation voltage signal with gradually increasing amplitude to the first group of curved piezoelectric ceramic groups (2-1-1), the rise time is t2, and t2<<t1, the piezoelectric vibrator (2) generates an edge along X The bending deformation in the positive direction of the shaft reaches the initial position, and the mover (3) remains stationary due to inertia; Step two and three, repeating step two one to step two two, can realize the continuous motion output of the mover (3) along the negative direction of the X axis; (3) The specific process of driving the mover (3) to move forward along the Y axis is as follows: Step 31: Apply an excitation voltage signal with a gradually increasing amplitude to the second group of curved piezoelectric ceramic groups (2-1-2), the rise time is t1, and the piezoelectric vibrator (2) produces bending deformation along the positive direction of the Y axis to At the limit position, under the action of static friction, the mover (3) is driven by the driving foot (2-3) to generate displacement output along the positive direction of the Y axis; Step 32: Apply a voltage excitation signal with a gradually decreasing amplitude to the second group of curved piezoelectric ceramic groups (2-1-2), the falling time is t2, and t2<<t1, the piezoelectric vibrator (2) generates an edge along Y The shaft is bent and deformed to the initial position in the negative direction, and the mover (3) remains stationary due to inertia; Step 33, repeating step 31 to step 32, the continuous motion output of the mover (3) along the positive direction of the Y axis can be realized; (4) The specific process of driving the mover (3) to move in the negative direction along the Y axis is: Step 41: Apply an excitation voltage signal with a gradually decreasing amplitude to the second group of curved piezoelectric ceramic groups (2-1-2), and the falling time is t1, and the piezoelectric vibrator (2) generates bending deformation along the negative direction of the Y axis to At the limit position, under the action of static friction, the mover (3) is driven by the driving foot (2-3) to generate displacement output along the negative direction of the Y axis; Step 42: Apply an excitation voltage signal with gradually increasing amplitude to the second group of curved piezoelectric ceramic groups (2-1-2), the falling time is t2, and t2<<t1, the piezoelectric vibrator (2) generates an edge Y The bending deformation in the positive direction of the shaft reaches the initial position, and the mover (3) remains stationary due to inertia; Step 43, repeat step 41 to step 42, the continuous motion output of the mover (3) along the negative direction of the Y-axis can be realized. 2. The excitation method for the two-degree-of-freedom motion realized by the two-degree-of-freedom piezoelectric driver using the bending piezoelectric vibrator according to claim 1, characterized in that, the first group of bending piezoelectric ceramic groups (2-1 -1) and two adjacent piezoelectric ceramic sheets in the second group of curved piezoelectric ceramic groups (2-1-2) are provided with energized electrode sheets (2-4). 3. The excitation method for the two-degree-of-freedom motion realized by the two-degree-of-freedom piezoelectric driver using the bending piezoelectric vibrator according to claim 1, wherein the mover (3) is a cylindrical mover, a ball type mover or planar mover. 4. The excitation method of the two-degree-of-freedom motion realized by the two-degree-of-freedom piezoelectric driver using the bending piezoelectric vibrator according to claim 1, wherein the waveform of the voltage excitation signal applied in the method is an asymmetrical triangular wave or an asymmetric trapezoidal wave. 5. The excitation method of the two-degree-of-freedom motion realized by the two-degree-of-freedom piezoelectric driver that adopts the bending piezoelectric vibrator according to claim 3 is characterized in that, when the mover (3) is a planar mover, the drive mover The element (3) moves positively or negatively along the X-axis, and moves positively or negatively along the Y-axis. The specific performance is: in the plane where the planar mover is located, drive the planar mover along the positive or negative direction of the X-axis. movement in the positive or negative direction along the Y axis. 6. The excitation method for the two-degree-of-freedom motion realized by the two-degree-of-freedom piezoelectric driver using the bending piezoelectric vibrator according to claim 3, characterized in that, when the mover (3) is a cylindrical mover, the drive mover The element (3) moves positively or negatively along the X-axis, and moves positively or negatively along the Y-axis, specifically: driving the cylindrical mover to move positively or negatively along the X-axis, and clockwise around the X-axis Or counterclockwise rotation with two degrees of freedom. 7. The excitation method for the two-degree-of-freedom motion realized by the two-degree-of-freedom piezoelectric driver that adopts the bending piezoelectric vibrator according to claim 3 is characterized in that, when the mover (3) is a spherical mover, the drive mover The child (3) moves positively or negatively along the X-axis, and positively or negatively along the Y-axis, specifically: driving the spherical mover to rotate clockwise or counterclockwise around the X-axis, and clockwise around the Y-axis Or counterclockwise rotation with two degrees of freedom.