Composite drive type multi-degree-of-freedom cross-scale piezoelectric robot

Abstract

The invention discloses a composite driving type multi-degree-of-freedom cross-scale piezoelectric robot, and relates to the technical field of piezoelectric driving. The device comprises an ultrasonic main body and mass blocks which are symmetrically arranged relative to the ultrasonic main body; the mass block is connected with a first driving foot, the side face of the mass block is connected with the side face of the ultrasonic body through a flexible hinge and a cross beam, and first piezoelectric ceramic pieces are attached to the two sides of the cross beam. A second driving foot is arranged on one side surface of the ultrasonic main body, and second piezoelectric ceramic pieces are symmetrically arranged on the other three side surfaces relative to the cross beam; the first piezoelectric ceramic piece drives the cross beam to bend, the mass blocks on the two sides swing in the same direction, linear driving is achieved, and rotation driving is achieved through reverse swing. The mass blocks are connected to the two sides of the ultrasonic body, sawtooth wave excitation voltage is applied to the first piezoelectric ceramic pieces on the two sides of the cross beams, so that the two cross beams are bent in the same direction or in the opposite directions, linear driving and rotary driving are achieved, and the problem that an existing driver cannot meet multi-freedom movement is solved.

Description

Technical Field

[0001] The present invention belongs to the field of piezoelectric drive technology, and in particular relates to a composite drive type multi-degree-of-freedom cross-scale piezoelectric robot. Background Art

[0002] The motor converts electrical energy into mechanical energy through the inverse piezoelectric effect of piezoelectric materials, making it suitable for high-precision and high-resolution precision instruments. Most existing ultrasonic piezoelectric motors can only achieve reciprocating motion in one degree of freedom.

[0003] For example, Chinese invention CN118017868A discloses a dual-degree-of-freedom ultrasonic micromotor, which uses six piezoelectric ceramic plates on the side of the output block to drive the output block to bend and deform, and uses a driving foot to drive the output member to move. By changing the orientation of the output member and the excitation signal, the output member can be moved in different directions, thereby achieving dual-degree-of-freedom movement through a single piezoelectric driver.

[0004] However, the above-mentioned prior art can only realize movement within a plane, and cannot realize both movement within a plane and plane rotation, thereby failing to meet the multi-freedom movement requirements of the piezoelectric robot. Summary of the Invention

[0005] The purpose of the present invention is to provide a composite-driven multi-degree-of-freedom cross-scale piezoelectric robot, which connects mass blocks on both sides of the ultrasonic body through flexible hinges and beams, and applies a sawtooth wave excitation voltage to the first piezoelectric ceramic sheets on both sides of the beam, so that the two beams bend in the same or opposite directions, realizing linear drive and rotational drive, and solving the problem that existing drivers cannot meet the requirements of multi-degree-of-freedom movement.

[0006] To solve the above technical problems, the present invention is achieved through the following technical solutions:

[0007] The present invention relates to a composite-driven multi-degree-of-freedom cross-scale piezoelectric robot, comprising an ultrasonic body and a mass block symmetrically arranged relative to the ultrasonic body; a first driving foot is connected to one surface of the mass block, a side surface of the mass block is connected to a beam via a flexible hinge, the other end of the beam is connected to the side surface of the ultrasonic body via a flexible hinge, and both sides of the beam are covered with a first piezoelectric ceramic sheet; the ultrasonic body is a rectangular parallelepiped structure, and a second driving foot is symmetrically arranged on one side surface of the ultrasonic body relative to the beam, and second piezoelectric ceramic sheets are symmetrically arranged on the other three sides relative to the beam; wherein the first driving foot and the second driving foot are located in the same plane, and are used to drive the beam to bend through the first piezoelectric ceramic sheet, and utilize the mass blocks on both sides of the ultrasonic body to swing in the same direction to achieve linear drive, and reverse swing to achieve rotational drive.

[0008] As a preferred technical solution of the present invention, the mass block, flexible hinge, beam and ultrasonic body are an integrated structure.

[0009] As a preferred technical solution of the present invention, the crossbeam is connected to the middle position of the ultrasonic body.

[0010] As a preferred technical solution of the present invention, the crossbeam is a plate structure.

[0011] As a preferred technical solution of the present invention, the cross-section of the ultrasonic body is square.

[0012] As a preferred technical solution of the present invention, a through hole is provided at the center of the end surface of the ultrasonic body.

[0013] A driving method for a composite-driven multi-degree-of-freedom cross-scale piezoelectric robot, comprising:

[0014] Rotational drive is achieved by applying a sawtooth wave excitation voltage to the first piezoelectric ceramic plates on both sides of the beam, causing the two beams to bend in opposite directions, causing the two mass blocks to swing in opposite directions, thereby achieving rotational drive.

[0015] Linear drive: By applying a sawtooth wave excitation voltage to the first piezoelectric ceramic plates on both sides of the beam, the two beams are bent in the same direction, causing the two mass blocks to swing in the same direction, thereby achieving linear drive.

[0016] As a preferred technical solution of the present invention, the linear drive includes applying an excitation signal to the second piezoelectric ceramic piece to cause the ultrasonic body to bend and deform, and utilizing the second driving foot to generate linear drive.

[0017] The present invention has the following beneficial effects:

[0018] The present invention connects mass blocks on both sides of the ultrasonic body through flexible hinges and beams, and applies a sawtooth wave excitation voltage to the first piezoelectric ceramic sheets on both sides of the beam, so that the two beams bend in the same or opposite directions, thereby realizing linear and rotational drive within the plane of the piezoelectric robot, effectively meeting the multi-freedom movement requirements and improving the overall driving flexibility.

[0019] At the same time, the first piezoelectric ceramic piece is used to drive the beam to bend, and the swing of the mass block generates inertial drive to achieve displacement accumulation and directional drive. Compared with the ultrasonic body, it can achieve higher displacement accuracy. Moreover, the ultrasonic body can be used to achieve the purpose of high-speed movement, thereby achieving cross-scale movement with the inertial drive generated by the swing of the mass block. It has strong movement flexibility and can complete complex movement tasks in a shorter time than traditional motors, with higher work efficiency, realizing a performance leap from high precision to high speed.

[0020] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0022] Figure 1 This is a schematic structural diagram of a composite drive multi-degree-of-freedom cross-scale piezoelectric robot according to the present invention;

[0023] Figure 2 for Figure 1 A top view of

[0024] Figure 3 for Figure 2 Schematic diagram of the structure from an upward perspective;

[0025] Figure 4 This is a structural diagram of the drive module when it is rotating;

[0026] Figure 5 This is a schematic diagram of the structure of the drive module when it is driving linearly;

[0027] In the accompanying drawings, the components represented by the reference numerals are as follows:

[0028] 1-ultrasonic body, 2-mass block, 3-first piezoelectric ceramic sheet, 4-second piezoelectric ceramic sheet, 101-second driving foot, 102-through hole, 201-first driving foot, 202-crossbeam. DETAILED DESCRIPTION

[0029] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0030] In the description of the present invention, it should be understood that the terms "opening", "upper", "lower", "thickness", "top", "middle", "length", "inside", "around" and the like indicating orientation or positional relationship are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the components or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0031] Example 1

[0032] See also Figures 1 to 3 As shown, the present invention is a composite-driven, multi-degree-of-freedom, cross-scale piezoelectric robot comprising an ultrasonic body 1 and a mass block 2 symmetrically arranged relative to the ultrasonic body 1. The mass block 2 can be a cube or a rectangular parallelepiped structure. A first driving foot 201 is connected to one surface of the mass block 2. A crossbeam 202 is connected to the side of the mass block 2 via a flexible hinge. The other end of the crossbeam 202 is connected to the side of the ultrasonic body 1 via a flexible hinge.

[0033] The mass block 2, flexible hinge, beam 202, and ultrasonic body 1 form an integrated structure. Beam 202 is connected to the center of the ultrasonic body 1 and is a plate-like structure. Both beams 202 are coated with first piezoelectric ceramic sheets 3, four in total, as shown in the figure and numbered 3-1, 3-2, 3-3, and 3-4. 3-1 and 3-2 are located on opposite sides of the same beam 202, while 3-3 and 3-4 are located on opposite sides of the same beam 202. 3-1 and 3-3 are on the same side, and 3-2 and 3-4 are on the same side.

[0034] The ultrasonic body 1 has a rectangular parallelepiped structure, with a second driving foot 101 symmetrically positioned on one side relative to the crossbeam 202. Six second piezoelectric ceramic plates 4 are also symmetrically positioned on the remaining three sides relative to the crossbeam 202. The ultrasonic body 1 has a square cross-section and a through-hole 102 at the center of its end face. The presence of this through-hole 102 improves the deformability of the ultrasonic body 1.

[0035] Among them, the first driving foot 201 and the second driving foot 101 are located in the same plane, and are used to drive the crossbeam 202 to bend through the first piezoelectric ceramic piece 3, and use the mass blocks 2 on both sides of the ultrasonic body 1 to swing in the same direction to achieve linear drive, and to swing in the opposite direction to achieve rotational drive.

[0036] Example 2

[0037] A driving method for a composite-driven multi-degree-of-freedom cross-scale piezoelectric robot includes a quasi-static inertial driving mode:

[0038] like Figure 4As shown, during rotational drive, a sawtooth wave excitation voltage is applied to the first piezoelectric ceramic plates 3 on both sides of the beam 202. For example, a sawtooth wave voltage in the same direction and phase is applied to the first piezoelectric ceramic plates 3-1 and 3-4, while a sawtooth wave voltage in the opposite direction to that of 3-1 and 3-4 is applied to 3-2 and 3-3. This causes the two beams 202 to bend in opposite directions, causing the two mass blocks 2 to swing in opposite directions. Specifically, by applying a sawtooth wave voltage that rises slowly and falls quickly, the left mass block 2 moves downward and the right mass block 2 moves upward, generating movement through the first driving foot 201, thereby driving the piezoelectric robot to rotate about its center of symmetry.

[0039] During the second half of the cycle, the four first piezoelectric ceramic plates 3 rapidly return to their original lengths under the influence of the steep voltage drop, and the crossbeam 202 quickly returns to its initial state. This rapid recovery minimizes the impact on the ultrasonic body 1, allowing for angle accumulation. This repetitive cycle enables the robot to generate high-precision rotational motion.

[0040] like Figure 5 As shown, during linear driving, a sawtooth wave excitation voltage is applied to the first piezoelectric ceramic pieces 3 on both sides of the beam 202, so that the two beams 202 bend in the same direction, and the two mass blocks 2 swing in the same direction, thereby achieving linear driving.

[0041] Specifically, a sawtooth voltage with a slow rise and fast fall in the same direction and phase is applied to the first piezoelectric ceramic sheets 3-1 and 3-3, while a sawtooth voltage in the opposite direction to 3-1 and 3-3 is applied to 3-2 and 3-4. This causes the two beams 202 to bend in the same direction. As shown in the figure, the two masses 2 swing upward synchronously, generating motion through the first drive feet 201, which in turn drives the piezoelectric robot to move along the polarization direction of the ceramic sheets. During the second half of the cycle, the four first piezoelectric ceramic sheets 3 quickly return to their original lengths under the influence of the steeply falling voltage signal, and the beams quickly return to their initial state. Due to the rapid recovery, the impact on the ultrasonic body 1 is minimal. This cycle repeats, generating long-range linear motion.

[0042] Piezoelectric direct-push drive mode:

[0043] In this mode, only one pulse signal is applied to the four first piezoelectric ceramic pieces 3. The beams 202 on both sides play a key role in this process. The first piezoelectric ceramic pieces 3 attached to the beams 202 produce a slight deformation after receiving the pulse signal. The beams 202 will transmit and amplify this slight deformation, and then convert it into linear motion or rotational motion.

[0044] Every time the first piezoelectric ceramic sheet 3 deforms, it drives the piezoelectric robot or moving part forward a tiny step distance of only a few nanometers. This precise control method can improve the movement accuracy of the moving part to the nanometer level, meeting the needs of work scenarios with extremely high precision requirements.

[0045] Also includes resonant drive modes:

[0046] In this mode, linear drive is achieved through the deformation of the ultrasonic body 1. By applying an excitation signal to the second piezoelectric ceramic piece 4, the ultrasonic body 1 is bent and deformed, and the second driving foot 101 is used to generate linear drive. The specific excitation signal driving process can refer to the driving process in the existing technology in the background technology to achieve the linear drive effect of the ultrasonic motor, thereby obtaining a faster linear movement speed.

[0047] This generates inertial drive with the swing of mass block 2 to achieve cross-scale movement, with strong movement flexibility. Compared with traditional motors, it can complete complex movement tasks in a shorter time and has higher work efficiency, achieving a performance leap from high precision to high speed.

[0048] Throughout this specification, references to terms such as "one embodiment," "example," or "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0049] The preferred embodiments of the present invention disclosed above are intended only to help illustrate the present invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the present invention to the specific embodiments described. Obviously, many modifications and variations are possible based on the content of this specification. These embodiments are selected and described in detail in this specification to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A composite drive multi-degree-of-freedom cross-scale piezoelectric robot, characterized by: It comprises an ultrasonic body (1) and a mass block (2) symmetrically arranged relative to the ultrasonic body (1); A first driving foot (201) is connected to one surface of the mass block (2), a crossbeam (202) is connected to the side of the mass block (2) via a flexible hinge, the other end of the crossbeam (202) is connected to the side of the ultrasonic body (1) via a flexible hinge, and both sides of the crossbeam (202) are covered with a first piezoelectric ceramic sheet (3); The ultrasonic body (1) is a rectangular parallelepiped structure, and a second driving foot (101) is symmetrically arranged on one side of the ultrasonic body (1) relative to the crossbeam (2), and a second piezoelectric ceramic piece (4) is symmetrically arranged on the other three sides relative to the crossbeam (2); The first driving foot (201) and the second driving foot (101) are located in the same plane and are used to drive the crossbeam (2) to bend via the first piezoelectric ceramic plate (3), and to achieve linear drive by swinging the mass blocks (2) on both sides of the ultrasonic body (1) in the same direction, and to achieve rotational drive by swinging in opposite directions.

2. A compound-driven multi-degree-of-freedom cross-scale piezoelectric robot according to claim 1, characterized in that: The mass block (2), the flexible hinge, the crossbeam (202) and the ultrasonic body (1) are an integrated structure.

3. The compound-driven multi-degree-of-freedom cross-scale piezoelectric robot according to claim 1, characterized in that: The crossbeam (202) is connected to the middle position of the ultrasonic body (1).

4. A composite drive type multi-degree-of-freedom cross-scale piezoelectric robot according to claim 1 or 3, characterized in that: The crossbeam (202) is a plate structure.

5. The compound-driven multi-degree-of-freedom cross-scale piezoelectric robot according to claim 1, characterized in that: The cross-sectional shape of the ultrasonic body (1) is a square.

6. The compound-driven multi-degree-of-freedom cross-scale piezoelectric robot according to claim 5, characterized in that: A through hole (102) is provided at the center of the end surface of the ultrasonic body (1).

7. The driving method of a composite drive type multi-degree-of-freedom cross-scale piezoelectric robot according to claim 1, characterized in that: include: Rotational drive is achieved by applying a sawtooth wave excitation voltage to the first piezoelectric ceramic sheets (3) on both sides of the beam (202), causing the two beams (202) to bend in opposite directions, thereby causing the two mass blocks (2) to swing in opposite directions, thereby achieving rotational drive; Linear drive is achieved by applying a sawtooth wave excitation voltage to the first piezoelectric ceramic sheets (3) on both sides of the beam (202), causing the two beams (202) to bend in the same direction, thereby causing the two mass blocks (2) to swing in the same direction, thereby achieving linear drive.

8. The driving method of a composite-drive multi-degree-of-freedom cross-scale piezoelectric robot according to claim 7, characterized in that: The linear drive comprises applying an excitation signal to the second piezoelectric ceramic piece (4) to cause the ultrasonic body (1) to bend and deform, and utilizing the second driving foot (101) to generate linear drive.

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