One-drive multi-action type piezoelectric inchworm driver

Abstract

The invention relates to a one-drive multi-action piezoelectric inchworm driver, which belongs to the technical field of piezoelectric precision driving and comprises a driving unit, a clamping unit, two printed circuit boards (PCBs) and a plurality of target moving bodies. The driving unit is composed of annular piezoelectric ceramics and a flexible mechanism; the clamping unit is embedded in a PCB, and three configuration schemes based on a magnetic elastomer, a shape memory alloy and an electromagnet are provided. Under the excitation of an electric control signal, the annular piezoelectric ceramic in the driving unit extends in the radial direction and drives the PCB to move up and down through the flexible mechanism; under the excitation of multiple paths of time sequence signals, a plurality of clamping units in the PCB can execute clamping and loosening actions; the driving unit is matched with the clamping unit, and the multiple target moving bodies can be controlled to move up and down independently. Through cooperative control of one driving unit and a plurality of clamping units, independent and synchronous positioning of a multi-target moving body is realized, the structure is simplified, the size is reduced, light weight is realized, and integration and miniaturization of a piezoelectric driving system are promoted.

Description

Technical Field

[0001] The present invention relates to a one-drive-multiple-move piezoelectric inchworm actuator, belonging to the technical field of piezoelectric precision drive. Background Art

[0002] With the rapid development of precision drive and positioning technologies, piezoelectric actuators have received extensive attention due to their high motion accuracy, simple structure, electromagnetic interference resistance, etc. A piezoelectric actuator is a device that generates mechanical motion based on the inverse piezoelectric effect, with core advantages such as high positioning accuracy, fast response speed, and large output force density, and has broad application prospects in many fields such as acoustics, optics, precision positioning, medical treatment, aerospace, etc.

[0003] According to different motion principles, piezoelectric actuators can be mainly divided into four categories: ultrasonic type, direct-acting type, inertial type, and inchworm type. Among them, the piezoelectric inchworm actuator is a type of piezoelectric actuator developed by imitating the motion principle of inchworms in nature. Traditional piezoelectric inchworm actuators mainly include a driving unit (1-3), two clamping units (1-1, 1-2), and a target moving body (1-4). Usually, by controlling the cooperation of a driving unit and two clamping units, the directional movement of a target moving body is achieved, so it is called "one-drive-one-move". The motion principle of the traditional one-drive-one-move piezoelectric inchworm actuator is as Figure 1 shown. The specific process of a single-cycle motion is as follows: In the initial state, there is no voltage at both ends of the piezoelectric element (1-3) of the driving unit and the piezoelectric elements (1-1, 1-2) of the clamping units, and all piezoelectric elements maintain their initial lengths. Step 1, the piezoelectric element (1-2) of the right clamping unit is energized, and this element elongates to clamp the target moving body (1-4); Step 2, the piezoelectric element (1-3) of the driving unit is energized, and this element elongates to push the right clamping unit (1-2) and the target moving body (1-4) to move rightward by a distance of ∆x; Step 3, the piezoelectric element (1-1) of the left clamping unit is energized, and this element elongates. At this time, the left and right clamping units (1-1, 1-2) jointly clamp the target moving body (1-4); Step 4, the piezoelectric element (1-2) of the right clamping unit is de-energized, and it returns to its original length to release the target moving body (1-4); Step 5, the piezoelectric element (1-3) of the driving unit is de-energized, and it returns to its original length; Step 6, the piezoelectric element (1-1) of the left clamping unit is de-energized, and it returns to its original length to release the target moving body (1-4), and at this time it is the same as the initial state. Under the excitation of a continuous time-sequence electric control signal (such as Figure 1 (b)), the piezoelectric inchworm actuator will repeat the above six steps cyclically to achieve continuous stepping motion, and theoretically has an infinite stroke. In summary, the traditional one-drive-one-move piezoelectric inchworm actuator has the advantages of large stroke, high resolution, and high load capacity.

[0004] With the growing demand for piezoelectric precision drive technology in high-end fields such as aerospace, biomedicine, optical engineering and precision machining, piezoelectric drivers have reached new heights in the optimization level requirements of comprehensive performance such as accuracy, speed, force, force density, power consumption, volume, degree of freedom and motion mode, greatly promoting the development of piezoelectric precision drive technology towards miniaturization, integration and intelligence. In particular, in cutting-edge application scenarios such as brain-computer interfaces and cell manipulation, it is urgent to use precision drive technology to achieve simultaneous control of multiple moving targets in a limited space. However, if the traditional one-drive-one-motion piezoelectric inchworm driver is to achieve the above goals, the number of drive units and clamping units needs to be doubled. Although it can achieve multi-target motion control, it still faces the dilemma of limited positioning accuracy, large structure, complex control, high cost, and the contradiction between the growing demand for the number of target moving bodies and the miniaturization and integration of the system, which to a certain extent limits the further development of related application fields and piezoelectric inchworm drive technology.

[0005] The present invention proposes a one-drive multi-action piezoelectric inchworm driver, which can realize synchronous and independent control of the motion of multiple target moving bodies through the cooperation of one drive unit and multiple clamping units, that is, "one-drive multi-action". If the number of target moving bodies needs to be increased, it is only necessary to increase the number of clamping units, which greatly simplifies the mechanical structure and control system, and to a certain extent solves the problem of the contradiction between multi-target motion control and system miniaturization and integration of the traditional one-drive one-action piezoelectric inchworm driver. In addition, since there is no need to increase the number of piezoelectric units, the cost is effectively controlled, which is expected to provide a set of practical and effective solutions for meeting the multi-target drive control needs for cutting-edge application scenarios such as brain-computer interfaces and cell operations. Summary of the invention

[0006] In view of the problems existing in the above-mentioned traditional one-drive one-motion piezoelectric inchworm driver, the present invention proposes a one-drive multi-motion piezoelectric inchworm driver. The present invention mainly comprises a target moving body 1 (2-1), a target moving body 2 (2-2), a target moving body 3 (2-3), a clamping unit (2-4), an upper printed circuit board (upper PCB) (2-5), a flexible mechanism (2-6), an annular piezoelectric ceramic (2-7), and a lower printed circuit board (lower PCB) (2-8).

[0007] Furthermore, the flexible mechanism (2-6) cooperates with the annular piezoelectric ceramic (2-7), and the annular piezoelectric ceramic is glued and fixed to the inside of the flexible mechanism using epoxy resin, and the two together form a driving unit of the piezoelectric inchworm driver. The flexible mechanism is orthogonally assembled using two regular octagonal flexible hinges, which are aligned with the centers of the upper and lower PCBs, and the flexible mechanism is glued and fixed to the upper and lower PCBs using epoxy resin; the lower PCB is fixed to the desktop, and holes are punched at the center positions of the upper and lower PCBs to allow the target moving body to pass through them.

[0008] Furthermore, when the driving unit works, the annular piezoelectric ceramic is energized and radially expands and deforms. The flexible mechanism converts the radial movement of the annular piezoelectric ceramic into an axial movement, thereby driving the upper PCB to move downward.

[0009] Furthermore, the multiple clamping units (2-4) are embedded in the PCB board and include conductive coils and clamping materials. Among them, under the control of different timing signals, the coils can control the states of the clamping materials of the multiple clamping units simultaneously by energizing and de-energizing, so that they can complete two actions of clamping and relaxing, thereby achieving the effect of simultaneously controlling the independent movements of multiple target moving bodies.

[0010] The present invention can drive multiple target moving bodies to move by using only one driving unit in cooperation with multiple clamping units, thereby realizing "one drive for multiple movements". The proposed one-drive-for-multiple-movements piezoelectric inchworm driver has the characteristics of small structure, large stroke, high resolution, simple electronic control system, expandable number of target moving bodies, and easy miniaturization and integration. Description of the Drawings

[0011] The present invention will be further described below with reference to the drawings and embodiments.

[0012] Figure 1 is the working principle diagram of a one-drive-for-one-movement piezoelectric inchworm driver in the prior art.

[0013] Figure 2 is the three-dimensional structure diagram and cross-sectional view of a one-drive-for-multiple-movements piezoelectric inchworm driver of the present invention.

[0014] Figure 3 is the working principle diagram of the flexible mechanism of a one-drive-for-multiple-movements piezoelectric inchworm driver of the present invention.

[0015] Figure 4 is the working principle diagram of the clamping unit of a one-drive-for-multiple-movements piezoelectric inchworm driver of the present invention. (a) Scheme 1: Based on the magneto-elastic effect of the magneto-elastic body, the clamping unit performs clamping and relaxing actions on the target moving body; (b) Scheme 2: Based on the shape memory effect of the shape memory alloy, the clamping unit generates clamping and relaxing actions on the target moving body; (c) represents Scheme 3: Based on the electromagnetic effect of the electromagnet, the clamping unit generates clamping and relaxing actions on the target moving body.

[0016] Figure 5 is the working principle diagram of the whole machine of a one-drive-for-multiple-movements piezoelectric driver of the present invention.

[0017] The labels in the attached drawings are noted as follows: 1-1 Left clamping unit of the traditional one-drive-one piezoelectric inchworm actuator; 1-2 Right clamping unit; 1-3 Driving unit; 1-4 Target moving body. 2-1 Target moving body one of the one-drive-multiple piezoelectric actuators; 2-2 Target moving body two; 2-3 Target moving body three; 2-4 Clamping unit embedded in the PCB, 2-4-1 Clamping unit embedded in the upper PCB, 2-4-2 Clamping unit embedded in the lower PCB; 2-5 Upper PCB; 2-6 Flexible mechanism, 2-6-1, 2-6-2 Octagonal flexible hinge; 2-7 Annular piezoelectric ceramic; 2-8 Lower PCB. 4-1 PCB, 4-1-1 Upper plate of the PCB, 4-1-2 Lower plate of the PCB; 4-2 Target moving body; 4-3 Smart material (taking magnetoelastic as an example, high elastic modulus state); 4-4 Smart material (taking magnetoelastic as an example, low elastic modulus state); 4-5 Driving unit; 4-6 Conductive coil; 4-7 Shape memory alloy in high-temperature phase shape (small inner diameter state); 4-8 Shape memory alloy in low-temperature phase shape (large inner diameter state); 4-9-1 Top view of the clamping unit using shape memory alloy (clamping state); 4-9-2 Top view of the clamping unit using shape memory alloy (relaxed state); 4-10 Magnet; 4-11 Soft magnetic material; 4-12 Sponge; 4-13-1 Top view of the clamping unit using electromagnet (clamping state); 4-13-2 Top view of the clamping unit using electromagnet (relaxed state); 4-14 Power supply; 4-15 Switch. 5-1 Upper plate of the PCB; 5-2 Lower plate of the PCB; 5-3 Annular piezoelectric ceramic; 5-4-1 Target moving body one; 5-4-2 Target moving body two; 5-4-3 Target moving body three; 5-5-1 to 5-5-6 Magnetoelastic; 5-6 Flexible mechanism; 5-7-1 to 5-7-6 Coils. Detailed implementation manners

[0018] The following will combine with the Figures 2 to 5 in the embodiments of the present invention to clearly and completely elaborate on the technical solutions in the embodiments of the present invention. It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other. The described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0019] As Figure 2 and Figure 3 shown, a one-drive-multiple piezoelectric inchworm actuator involved in this embodiment includes target moving body one (2-1), target moving body two (2-2), target moving body three (2-3), clamping unit (2-4), upper and lower printed circuit boards (PCBs) (2-5, 2-8), flexible mechanism (2-6), and annular piezoelectric ceramic (2-7). The flexible mechanism and the annular piezoelectric ceramic are combined to jointly form the driving unit of the piezoelectric inchworm actuator. Among them, the flexible mechanism is as Figure 2As shown, it is composed of two orthogonally arranged flexible hinges of regular octagons (2-6-1) and (2-6-2), and the front elevation sectional view is as Figure 2 (b) shown, and the deformation condition is as Figure 3 shown; the annular piezoelectric ceramic (2-7) is adhesively fixed at the center positions of the four sides inside the flexible mechanism by epoxy resin glue. The upper and lower printed circuit boards (2-5) and (2-8) are also adhesively bonded to the upper and lower ends of the flexible mechanism by epoxy resin glue and are both parallel to the horizontal plane. The upper and lower printed circuit boards are aligned with the center of the flexible mechanism and both are provided with coaxial through holes, through which the target moving bodies (2-1, 2-2, 2-3) can pass.

[0020] Figure 2 (b) The clamping units (2-4-1) and (2-4-2) in it provide three sets of solutions in this embodiment, specifically as Figure 4 shown.

[0021] Solution 1: As Figure 4 (a) shown, a magnetoelastic material is embedded in the conical container in the upper half of the PCB (4-1). Based on the magnetoelastic effect, its elastic modulus can change with the change of the external magnetic field; a conductive coil is embedded in the lower half of the PCB (4-1). By applying high and low level signals to the conductive coil for excitation, the magnetic field around the magnetoelastic material can be changed, thereby changing the elastic modulus of the magnetoelastic material, and then realizing the clamping and releasing actions of the clamping unit on the target moving body. Specifically, when the conductive coil is excited by a high level of the coil clamping signal (the switch (4-15) is closed and the conductive coil (4-6) is powered on), an electromagnetic field is generated. This electromagnetic field acts on the magnetoelastic material to increase its elastic modulus, and the magnetoelastic material exerts a squeezing effect on the target moving body to perform the clamping action (as shown in (4-3)); when the clamping signal changes from high level to low level (the switch (4-15) is opened and the conductive coil (4-6) is disconnected from the power supply), the electromagnetic field action disappears. At this time, the elastic modulus of the magnetoelastic material decreases, and the magnetoelastic material does not exert a squeezing effect on the target moving body to perform the releasing action (as shown in (4-4)). Figure 4 (a) The right figure in it simulates the movement of a single target moving body under the condition of a clamping unit composed of a magnetoelastic material and a coil, where the upper PCB (4-1-1) is movable and the lower PCB (4-1-2) is fixed. When the upper switch is closed and the conductive coil is powered on, the coil generates a magnetic field under the excitation of a high level of the clamping signal, making the elastic modulus of the magnetoelastic material increase and generating a clamping effect; when the lower switch is opened and the conductive coil is powered off, the elastic modulus of the magnetoelastic material decreases and the clamping effect is lost. Obviously, the driving unit (4-5) can generate vertical up and down telescopic movement under the excitation of a periodic electric control signal. Cooperating with the clamping / releasing actions of the above clamping unit, it can drive the upper board of the PCB and the target moving body to achieve periodic stepping movement together.

[0022] Solution 2: As shown in Figure 4 (b), in the upper half of the PCB (4-1), annular clamping blocks (4-7 and 4-8) made of shape memory alloy are embedded. The shapes of the high-temperature phase (4-7) and low-temperature phase (4-8) of the clamping blocks are preset in advance. Based on the two-way memory effect of the shape memory alloy material, when the switch is closed and the conductive coil is energized, its temperature rises, causing the annular clamping blocks to be heated. Under the action of the shape memory effect, the inner diameter of the annular clamping blocks decreases, tightly wrapping the target moving body to achieve a clamping effect; when the switch is opened and the conductive coil is de-energized, its temperature drops, causing the annular clamping blocks to cool. Under the action of the shape memory effect, the inner diameter of the annular clamping blocks increases, and the clamping effect disappears.

[0023] Solution 3: As shown in Figure 4 (c), a conical container is embedded in the upper half of the PCB (4-1). The inner wall (4-11) is filled with soft magnetic material, and an annular magnet (4-10) is placed in the middle. A sponge (4-12) is wrapped around the target moving body for protection. When the switch is closed and the conductive coil is energized, a generated magnetic field makes the magnet produce a downward magnetic force, squeezing and clamping the target moving body through the inclined plane; when the conductive coil is de-energized, the magnetic field disappears, and the clamping effect of the inclined plane on the target mover disappears.

[0024] Particularly, the intelligent materials that can be selected for the clamping unit in the embodiments of the present invention include, but are not limited to, the above three types of materials: magnetic elastomer, shape memory alloy, and soft magnet. Other intelligent materials whose elastic modulus can change with external environmental factors such as electric field, magnetic field, and temperature can also be used.

[0025] As shown in Figure 5As shown, taking the solution of using a magnetoelastic body as the clamping unit clamping material as an example, the overall working principle of the one-drive-multiple-movement piezoelectric inchworm actuator according to the embodiments of the present invention is described in detail. The entire actuator is fixed by the lower PCB board. In the initial state, the annular piezoelectric ceramic is at the initial radius, the conductive coil 1 (5-7-1) is powered off, and the magnetoelastic body (5-5-1) is in a low elastic modulus state, performing a relaxation action on the target moving body 1 (5-4-1); the conductive coil 2 (5-7-2) generates a magnetic field under the excitation of the high level of the clamping signal, so that the magnetoelastic body (5-5-2) is in a high elastic modulus state and generates a clamping effect on the target moving body 1 (5-4-1); similarly, the conductive coil 3 (5-7-3) is powered off, the magnetoelastic body 1 (5-5-1) is in a low elastic modulus state, the clamping unit performs a relaxation action on the target moving body 1 (5-4-1), the conductive coil 4 (5-7-4) is powered on, the magnetoelastic body 4 (5-5-4) is in a high elastic modulus state, and the clamping unit performs a clamping action on the target moving body 2 (5-4-2); the conductive coil 5 (5-7-5) is powered on, the magnetoelastic body 5 (5-5-5) is in a high elastic modulus state, the clamping unit performs a clamping action on the target moving body 3 (5-4-3), the conductive coil 6 (5-7-6) is powered off, the magnetoelastic body 6 (5-5-6) is in a low elastic modulus state, and the clamping unit performs a relaxation action on the target moving body 3 (5-4-3). When working, it is divided into five steps: Step 1: The annular piezoelectric ceramic 5-3 radially expands under the excitation of a high-level signal. Its radial motion is converted into axial motion through a flexible mechanism, thereby driving the upper PCB (5-1) to move downward by ∆s1. The conductive coil 1 (5-7-1) is powered off, and the magnetic elastomer 1 (5-5-1) is in a low elastic modulus state. The clamping unit performs a relaxation action on the target moving body 1 (5-4-1); the conductive coil 2 (5-7-2) is powered on, and the magnetic elastomer 2 (5-5-2) is in a high elastic modulus state. The clamping unit performs a clamping action on the target moving body 1 (5-4-1), and the target moving body 1 (5-4-1) remains stationary; the conductive coil 3 (5-7-3) is powered off, and the magnetic elastomer 3 (5-5-3) is in a low elastic modulus state. The clamping unit performs a relaxation action on the target moving body 2 (5-4-2); the conductive coil 4 (5-7-4) is powered on, and the magnetic elastomer 4 (5-5-4) is in a high elastic modulus state. The clamping unit performs a clamping action on the target moving body 2 (5-4-2), and the target moving body 2 (5-4-2) remains stationary; the conductive coil 5 (5-7-5) is powered on, and the magnetic elastomer 5 (5-5-5) is in a high elastic modulus state. The clamping unit performs a clamping action on the target moving body 3 (5-4-3); the conductive coil 6 (5-7-6) is powered off, and the magnetic elastomer 6 (5-56) is in a low elastic modulus state. The clamping unit performs a relaxation action on the target moving body 3 (5-4-3). Under the clamping effect, the target moving body 3 (5-5-3) moves downward one step together with the upper PCB (5-1), denoted as ∆x1.

[0026] Step 2: The annular piezoelectric ceramic (5-3) remains under the excitation of a high-level signal. The conductive coil 1 (5-7-1) is powered on, and the magnetic elastomer 1 (5-5-1) is in a high elastic modulus state. The clamping unit performs a clamping action on the target moving body 1 (5-4-1); the conductive coil 2 (5-7-2) is powered on, and the magnetic elastomer 2 (5-5-2) is in a high elastic modulus state. The clamping unit performs a clamping action on the target moving body 1 (5-4-1); the conductive coil 3 (5-7-3) is powered off, and the magnetic elastomer 3 (5-5-3) is in a low elastic modulus state. The clamping unit performs a relaxation action on the target moving body 2 (5-4-2); the conductive coil 4 (5-7-4) is powered off, and the magnetic elastomer 5 (5-5-5) is in a low elastic modulus state. The clamping unit performs a relaxation action on the target moving body 2 (5-4-2); the conductive coil 5 (5-7-5) is powered on, and the magnetic elastomer 5 (5-5-5) is in a high elastic modulus state. The clamping unit performs a clamping action on the target moving body 3 (5-4-3), and the conductive coil 6 (5-7-6) is powered on; the magnetic elastomer 6 (5-5-6) is in a high elastic modulus state. The clamping unit performs a clamping action on the target moving body 3 (5-4-3).

[0027] Step 3: The annular piezoelectric ceramic 5-3 is kept under high-level signal excitation, the conductive coil 1 (5-7-1) is powered off, the magnetic elastomer 1 (5-5-1) is in the low elastic modulus state, and the clamping unit performs a relaxation action on the target moving body 1 (5-4-1); the conductive coil 2 (5-7-2) is powered on, the magnetic elastomer 2 (5-5-2) is in the high elastic modulus state, and the clamping unit performs a clamping action on the target moving body 1 (5-4-1); the conductive coil 3 (5-7-3) is powered on, the magnetic elastomer 3 (5-5-3) is in the high elastic modulus state, and the clamping unit performs a clamping action on the target moving body 2 (5-4-2); the conductive coil 4 (5-7-4) is powered off, the magnetic elastomer 4 (5-5-4) is in the low elastic modulus state, and the clamping unit performs a relaxation action on the target moving body 2 (5-4-2); the conductive coil 5 (5-7-5) is powered off, the magnetic elastomer 5 (5-5-5) is in the low elastic modulus state, and the clamping unit performs a relaxation action on the target moving body 3 (5-4-3); the conductive coil 6 (5-7-6) is powered on, the magnetic elastomer 6 (5-5-6) is in the high elastic modulus state, and the clamping unit performs a clamping action on the target moving body 3 (5-4-3).

[0028] Step 4: After the annular piezoelectric ceramic (5-3) is powered off, it resumes its original radius. The radial movement is converted into axial movement through the flexible mechanism, thereby driving the upper PCB (5-1) to move upward by ∆s2. The conductive coil 1 (5-7-1) is powered off, the magnetic elastomer 1 (5-5-1) is in the low elastic modulus state, and the clamping unit performs a relaxation action on the target moving body 1 (5-4-1); the conductive coil 2 (5-7-2) is powered on, the magnetic elastomer 2 (5-5-2) is in the high elastic modulus state, and the clamping unit performs a clamping action on the target moving body 3 (5-4-3), and the target moving body 1 (5-4-1) remains in place; the conductive coil 3 (5-7-3) is powered on, the magnetic elastomer 3 (5-5-3) is in the high elastic modulus state, and the clamping unit performs a clamping action on the target moving body 2 (5-4-2); the conductive coil 4 (5-7-4) is powered off, the magnetic elastomer 4 (5-5-4) is in the low elastic modulus state, and the clamping unit performs a relaxation action on the target moving body 2 (5-4-2). Under the clamping action, the target moving body 2 (5-5-2) moves upward one step together with the upper PCB (5-1), denoted as ∆x1; the conductive coil 5 (5-7-5) is powered off, the magnetic elastomer 5 (5-5-5) is in the low elastic modulus state, and the clamping unit performs a relaxation action on the target moving body 3 (5-4-3); the conductive coil 6 (5-7-6) is powered on, the magnetic elastomer 6 (5-5-6) is in the high elastic modulus state, and the clamping unit performs a clamping action on the target moving body 3 (5-4-3), and the target moving body 3 (5-5-3) remains stationary.

[0029] Step Five: The annular piezoelectric ceramic 5-3 remains powered off, and the six conductive coils (5-7-1 to 5-7-6) are all powered on. Therefore, the magneto-elastic bodies 1-6 (5-5-1 to 5-5-6) are all in the high elastic modulus state, and the clamping unit performs a clamping action on the three target moving bodies to lock the three target moving bodies.

[0030] In summary, under the excitation of the Figure 5 (a) electrical control timing signal, the actuator can achieve independent cooperative control of three target moving bodies simultaneously by using only a single driving unit, that is, the three target moving bodies can respectively achieve three different motion states: (1) remain stationary, (2) step down, and (3) step up. Under the excitation of the periodic electrical control timing signal, the target moving bodies can achieve continuous stationary / downward / upward stepping motion. The system has the advantages of high resolution, large stroke, simple mechanical structure and electrical control system, and the motion states of the target moving bodies can be independently controlled. And theoretically, the cluster control of the target moving bodies can be achieved by only increasing the clamping unit, which is beneficial to the miniaturization, integration and intelligent development of the piezoelectric inchworm actuator.

Claims

1. A one-drive multi-motion piezoelectric inchworm actuator mainly includes a first target moving body (2-1), a second target moving body (2-2), a third target moving body (2-3), a clamping unit (2-4), an upper printed circuit board (upper PCB) (2-5), a flexible mechanism (2-6), a ring piezoelectric ceramic (2-7), and a lower printed circuit board (lower PCB) (2-8), and is characterized in that, In principle, it is possible to achieve the function of independently synchronizing the positioning of multiple target moving bodies through the coordinated cooperation of a driving unit and multiple clamps.

2. It is characterized in that, The annular piezoelectric ceramic (2-7) cooperates with the flexible mechanism (2-6), and the two together constitute the driving unit of the piezoelectric inchworm driver. The flexible mechanism is composed of two orthogonally arranged flexible hinges in the shape of regular octagons. The annular piezoelectric ceramic is adhesively fixed at the center positions of the four sides inside the flexible mechanism with epoxy resin glue. The upper and lower PCBs are also adhesively bonded to the upper and lower ends of the flexible mechanism with epoxy resin glue and are both parallel to the horizontal plane. The upper and lower PCBs are aligned with the center of the flexible mechanism and both are provided with coaxial through holes, allowing the target moving body to pass through.

3. It is characterized in that, When the driving unit works, the annular piezoelectric ceramic is energized and radially expands and deforms. With the lower PCB fixed, the radial movement of the annular piezoelectric ceramic (2-7) is converted into axial movement through the flexible mechanism (2-6), driving the upper PCB to move downward. The multiple clamping units (2-4) are embedded in the PCB. Under the control of different timing signals, the clamping units can complete two actions: clamping and releasing. The driving unit can generate up-and-down telescopic movement in the vertical direction under the excitation of a periodic electric control signal. Cooperating with the clamping / releasing actions of the multiple clamping units, it can drive the upper PCB and multiple target moving bodies to achieve periodic stepping movement together, thus achieving the effect of simultaneously controlling the independent movement of multiple target moving bodies.

4. It is characterized in that, Multiple clamping units are embedded in the PCB. The clamping unit is composed of a clamping material and a conductive coil. The clamping material provides three effective solutions: First, a magnetoelastic elastomer (a material whose elastic modulus can change with the external magnetic field based on the magnetoelastic effect) is placed in a conical container in the upper half of the PCB. When the conductive coil in the lower half of the PCB is energized, an electromagnetic field is generated and acts on the magnetoelastic elastomer to increase its elastic modulus. The magnetoelastic elastomer exerts a squeezing effect on the target moving body to perform the clamping action. When the conductive coil is de-energized, the electromagnetic field effect disappears, the elastic modulus of the magnetoelastic elastomer decreases, and the magnetoelastic elastomer does not exert a squeezing effect on the target moving body to perform the relaxation action. Second, a ring-shaped clamping block is made based on the two-way memory effect of shape memory alloy and embedded in the upper half of the PCB. The shapes of the high-temperature phase and low-temperature phase of the clamping block are preset. When the conductive coil in the lower half of the PCB is energized, its temperature rises, causing the ring-shaped clamping block to be heated. Under the action of the shape memory effect, the inner diameter of the ring-shaped clamping block decreases, tightly wrapping the target moving body to play a clamping role. When the conductive coil is de-energized, its temperature drops, causing the ring-shaped clamping block to cool. Under the action of the shape memory effect, the inner diameter of the ring-shaped clamping block increases, and the clamping effect disappears. Third, based on the electromagnetic effect of an electromagnet, the inner wall of a conical container in the upper half of the PCB is filled with a soft magnetic material, and a ring magnet is embedded in the middle. When the switch is closed and the conductive coil is energized, a magnetic field is generated, causing the magnet to generate a downward magnetic force, and the target moving body is squeezed and clamped through the inclined plane. When the conductive coil is de-energized, the magnetic field disappears, and the clamping effect of the inclined plane on the target mover disappears. In particular, the intelligent materials that can be selected for the clamping unit include, but are not limited to, the above three types of materials: magnetoelastic elastomer, shape memory alloy, and soft magnetic. Any other intelligent materials whose elastic modulus can change with external environmental factors such as electric field, magnetic field, and temperature can be used.

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