Piezoelectric-driven self-growing enteroscope robot and working method thereof

Abstract

The invention discloses a piezoelectric-driven self-growing enteroscope robot and a working method thereof. The piezoelectric-driven self-growing enteroscope robot comprises a spiral lap joint mechanism, a piezoelectric driving mechanism and a set of diagnosis and treatment instruments. The spiral lap joint mechanism comprises a spiral lap joint belt, a guide rail and a guide rail base; the piezoelectric driving mechanism comprises two piezoelectric driving trolleys and a two-degree-of-freedom hinge mechanism; the diagnosis and treatment instrument comprises four cables. The piezoelectric driving mechanism is used for driving the spiral lap joint mechanism to lap the hollow solenoid in the intestinal tract, the colonoscope actively growing into the intestinal tract is formed, and linear motion control over the diagnosis and treatment instrument is achieved. The enteroscope robot provided by the invention is rigid and flexible, and can be used for accurately and nondestructively laying the built-in pipeline of the intestinal tract.

Description

Technical Field

[0001] The present invention relates to piezoelectric drive technology and continuous endoscope robots, and particularly to a piezoelectric-driven self-growing colonoscope robot and its working method. Background Art

[0002] Once colorectal cancer develops into the middle and late stages, it is extremely difficult to cure. Therefore, implementing effective cancer screening and early diagnosis and treatment is an important means to reduce the mortality rate of colorectal cancer, improve the survival rate and quality of life. However, traditional colonoscopes cannot actively deform during the operation, so there is a significant risk of stretching the colon and surrounding organs, which can cause pain and scars or perforations in the colon wall.

[0003] Using a belt structure with attached Velcro to form a hollow tubular structure by spiral lapping in the intestine by a piezoelectric drive mechanism, a colonoscope that actively grows into the intestine can be formed, which can well adapt to the complex and curved paths in the intestine and avoid compressing and damaging the intestinal wall. Utilizing the characteristics of multi-modal, multi-mode and direct drive of piezoelectric drive technology, the spiral lapping drive and the retraction and extension control of the diagnostic and treatment instruments are simultaneously realized by the same piezoelectric drive mechanism, which has the advantage of simple structure. The piezoelectric-driven self-growing colonoscope robot proposed by the present invention can solve the dilemma that it is difficult to balance rigidity and flexibility in the existing colonoscope system and establish a precise and non-destructive laying method for the internal pipeline in the intestine. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a piezoelectric-driven hull adsorption walking robot and its working mode aiming at the defects involved in the background art.

[0005] The present invention adopts the following technical solutions to solve the above technical problems: A piezoelectric-driven self-growing colonoscope robot, characterized in that it includes a spiral lapping mechanism, a piezoelectric drive mechanism and a diagnostic and treatment instrument; The spiral lapping mechanism includes a spiral lapping belt, a lapping guide rail and a guide rail seat. Among them, the spiral lapping belt is a soft belt with a shuttle-shaped cross-section, and the two side surfaces in the diagonal direction are respectively attached with the hook belt and the pile belt of the Velcro; the lapping guide rail is a wire structure formed by bending, with a guiding channel for the lapping belt to pass through in the middle, and annular guiding ends and fixed ends adapted to the cross-sectional shape of the lapping belt are respectively provided at both ends; the fixed end is connected to the guide rail seat; the guide rail seat is a rotating body structure formed by a T-shaped cross-section, with a through hole for passing through the lapping belt in the center, and the cross-sectional shape of the through hole is the same as the cross-sectional shape of the lapping belt; a fixed groove for connecting the fixed end of the lapping guide rail is provided on the end surface of the larger diameter side of the guide rail seat; the end surface of the smaller diameter side of the guide rail seat is the driving surface; the annular surface parallel to the end surface at the shoulder of the guide rail seat is the limiting surface; The piezoelectric driving mechanism includes a first to a second piezoelectric driving carriage, a two-degree-of-freedom hinge mechanism, a first to a fourth lever, and a medical instrument support. Among them, the first to the second piezoelectric driving carriages have the same structure and both include a piezoelectric vibrator, a threaded tube, and a first to a second wheel set; The first and second piezoelectric driving carriages are centrosymmetric about the center of the two-degree-of-freedom hinge mechanism; The piezoelectric vibrator includes a metal matrix and a first to a fourth piezoelectric ceramic sheet. Among them, the metal matrix is a hollow cylindrical tube symmetric about the axial symmetry plane, and the first to the fourth ceramic bonding planes are evenly distributed along the circumferential direction at the position of the axial symmetry plane; the metal matrix is provided with a first to a fourth strip groove evenly distributed along the circumferential direction near its first end face, and first to a fourth through holes are respectively provided in the direction perpendicular to the first to the fourth strip grooves. A first to a fourth driving surface is respectively provided at the middle position between every two strip grooves; the metal matrix is respectively provided with fifth to eighth strip grooves, fifth to eighth through holes, and fifth to eighth driving surfaces that are symmetric about the axial symmetry plane with respect to the first to the fourth strip grooves, first to the fourth through holes, and first to the fourth driving surfaces near its second end face; the inner hole of the metal matrix is provided with an internal thread that forms a threaded fit with the threaded tube; the first to the fourth piezoelectric ceramic sheets have the same structure and are respectively pasted on the first to the fourth ceramic bonding planes of the metal matrix, and are centrosymmetric about the center of the metal matrix and are polarized inward simultaneously along their thickness directions; The threaded tube is a hollow cylindrical tube provided with an external thread; two extension bosses are provided at the first end face of the threaded tube, and first to second hinge through holes for hinging with the two-degree-of-freedom hinge mechanism are respectively provided on the sides of the two bosses away from the threaded tube; The internal thread of the piezoelectric vibrator metal matrix and the external thread of the threaded tube in the first piezoelectric driving carriage are coarse threads; the internal thread of the piezoelectric vibrator metal matrix and the external thread of the threaded tube in the second piezoelectric driving carriage are fine threads, and the helix direction is opposite to that of the aforementioned coarse threads; The two-degree-of-freedom hinge mechanism includes first to fourth link rods, first to eighth rivets, and a connecting ring. Among them, the first to fourth link rods have the same structure, all being rectangular thin plates with chamfers at both ends; each of the nth link rod is provided with 2n + 1 and 2n + 2 articulated through-holes at both ends, where n is a natural number greater than or equal to 1 and less than or equal to 4; the connecting ring is a hollow cylinder with four circumferentially evenly distributed planes along the outer circumference of the cylindrical surface, and is provided with eleventh to fourteenth articulated through-holes whose centroid positions coincide with the centroids of the four planes; the third and fifth articulated through-holes of the first and second link rods are respectively matched with the first and second articulated through-holes of the threaded tube through the first to second rivets; the fourth and sixth articulated through-holes of the first and second link rods are respectively matched with the eleventh and thirteenth articulated through-holes of the connecting ring through the third to fourth rivets; the seventh and ninth articulated through-holes of the third and fourth link rods are respectively matched with the twelfth and fourteenth articulated through-holes of the connecting ring through the fifth to sixth rivets; the eighth and tenth articulated through-holes of the third and fourth link rods are respectively matched with the first and second articulated through-holes of the threaded tube in the second piezoelectric driving trolley through the seventh to eighth rivets; The first wheel set is a centrosymmetric structure including first to second rollers and first to second tension springs. Among them, the first to second rollers have the same structure, each including first to second wheels, a roller shaft, and first to second hooks; the roller shaft is a solid long and thin cylinder with diameters smaller at both ends than in the middle part; the first to second hooks have the same structure, each including first to second connection holes; the first to second hooks are symmetrically arranged at both ends of the small-diameter section of the roller shaft with respect to the axial symmetry plane of the roller shaft through their respective first connection holes and coincide with the shaft shoulders of the roller shaft; the first to second wheels have the same structure, both being hollow rotating bodies; the first to second wheels are symmetrically arranged on both sides of the first to second hooks, and their inner holes are concentric with the roller shaft; The first to second tension springs have the same structure, with two hooks on both sides; the hooks on both sides of the first tension spring are respectively connected to the second connection holes of the first hooks in the first to second rollers; the hooks on both sides of the second tension spring are respectively connected to the second connection holes of the second hooks in the first to second rollers; The first wheel set is located on the side of the second end face of the metal matrix, where the roller shafts of the first and second rollers are respectively tangent to the fifth and seventh driving surfaces; The second wheel set includes the first wheel set and a drum: the drum is a hollow thin-walled cylindrical tube, whose inner diameter is the same as the outer diameter of the tension spring; the drum is coaxially fitted with the first tension spring and their geometric centers coincide; The second wheel set is located on the side of the first cross-section of the metal matrix, where the roller shafts of the first and second rollers and the drum are respectively tangent to the first, third, and second driving surfaces; The first and third lever structures are the same, both are closed linear structures made of metal wire and have only a single plane of symmetry; the first and third levers each include a push rod, a fulcrum, and a cable limiting frame; the projections of the first and third lever structures on the plane of symmetry are a curve; the projections of the first and third lever structures on a plane perpendicular to their plane of symmetry are a closed curve; The second and fourth lever structures are the same, both are closed linear structures made of metal wire and have only a single plane of symmetry; the second and fourth levers each include a push rod, a fulcrum, and a cable limiting frame; the projections of the second and fourth lever structures on the plane of symmetry are a curve; the projections of the second and fourth lever structures on a plane perpendicular to their plane of symmetry are a closed curve; The first and second levers are installed on the first end face side of the metal substrate of the piezoelectric vibrator of the first piezoelectric driving trolley; the push rods of the first and second levers point to the second end face side of the metal substrate of the piezoelectric vibrator of the first piezoelectric driving trolley; the fulcrum of the first lever is matched with the first through hole of the metal substrate of the piezoelectric vibrator of the first piezoelectric driving trolley; the fulcrum of the second lever is matched with the second through hole of the metal substrate of the piezoelectric vibrator of the first piezoelectric driving trolley; The third and fourth levers are installed on the first end face side of the metal substrate of the piezoelectric vibrator of the second piezoelectric driving trolley; the push rods of the third and fourth levers point to the second end face side of the metal substrate of the piezoelectric vibrator of the second piezoelectric driving trolley; the fulcrum of the third lever is matched with the first through hole of the metal substrate of the piezoelectric vibrator of the second piezoelectric driving trolley; the fulcrum of the fourth lever is matched with the second through hole of the metal substrate of the piezoelectric vibrator of the second piezoelectric driving trolley; The diagnostic and therapeutic instrument includes the first to fourth cables; the first to fourth cables have the same structure, are all round-section cables, and the head diameter is larger than the rear cable; The cable limiting frames of the first to fourth levers respectively pass through the first to fourth cables; The support of the diagnostic and therapeutic instrument is a space linear structure made of metal wire, including four U-shaped bends and four superior arc frames. Among them, the four superior arc frames of the support of the diagnostic and therapeutic instrument are respectively matched with the shoulders at the variable cross-section of the heads of the first to fourth cables; the four U-shaped bends of the support of the diagnostic and therapeutic instrument are respectively matched with the first to fourth strip-shaped grooves of the metal substrate of the piezoelectric vibrator of the first piezoelectric driving trolley and fit the bottom of the grooves;

[0006] The present invention also discloses a driving method for the linear growth mode of the piezoelectric-driven self-growing colonoscope machine, including the following steps: If it is necessary to drive the first piezoelectric driving trolley: Apply the first to fourth electrical signals to the first to fourth piezoelectric ceramic sheets of the first piezoelectric driving trolley respectively; the first to fourth electrical signals are all AC harmonic signals, and the first to third electrical signals lead the second to fourth electrical signals by π / 2 in time respectively. The first to fourth electrical signals simultaneously excite the first-order bending vibration modes of the piezoelectric vibrator in two spatially orthogonal directions. Through the coupling of the two modes, micro-amplitude elliptical vibration trajectories are formed on the particles on the inner threaded surface of the piezoelectric vibrator, and the threaded tube is driven to rotate through the frictional effect; if it is necessary to drive the threaded tube to rotate in the reverse direction, make the first to third electrical signals lag the second to fourth electrical signals by π / 2 in time; If it is necessary to drive the second piezoelectric driving trolley, the way of applying the electrical signal is the same as that when driving the first piezoelectric driving trolley; When driving the second piezoelectric driving trolley, the threaded tube therein generates a combined rotational and linear motion. Since the piezoelectric vibrator in the first piezoelectric driving trolley does not vibrate and the wheel set is in a friction self-locking state, the first piezoelectric driving trolley is fixed; the linear motion of the screw in the second piezoelectric driving trolley pushes the guide rail seat away from the piezoelectric vibrator, and transfers the combined rotational and linear motion to the overlapping guide rail, guiding the spiral overlapping belt to spiral overlap from the inside of the solenoid, forming the self-growth of the solenoid; After growing a certain distance, drive the first piezoelectric driving trolley to make the threaded tube therein rotate in the reverse direction and disengage from the guide rail seat, and at the same time make the piezoelectric vibrator in the first piezoelectric driving trolley generate a forward linear displacement; Alternately performing the above two kinds of driving can realize the continuous linear growth of the solenoid;

[0007] The present invention also discloses a driving method for the bending growth of the piezoelectric-driven self-growing colonoscope robot, which includes the following steps: In the bending growth working mode, the driving methods for the first and second piezoelectric driving trolleys are the same as those in the linear growth mode; Drive the threaded tube in the second piezoelectric driving trolley to generate a combined rotational and linear motion. Since the piezoelectric vibrator in the first piezoelectric driving trolley does not vibrate and the wheel set is in a friction self-locking state, the first piezoelectric driving trolley is fixed; the linear motion of the screw in the second piezoelectric driving trolley pushes the guide rail seat away from the piezoelectric vibrator, and transfers the combined rotational and linear motion to the overlapping guide rail, guiding the spiral overlapping belt to spiral overlap from the inside of the solenoid, forming the self-growth of the solenoid; When the threaded tube rotates 180 degrees, switch to driving the threaded tube in the first piezoelectric driving trolley to rotate in the same direction, transfer the same-direction rotational motion and the reverse linear motion to the overlapping guide rail, so that the overlapping belt generates an axial retraction while maintaining the spiral overlap, forming the bending of the neutral axis of the solenoid; Repeating the above two kinds of driving can realize the bending growth of the linear solenoid;

[0008] The present invention also discloses a working mode for the collection and release of the diagnostic and therapeutic instruments of the piezoelectric-driven self-growing colonoscopy robot, which includes the following steps: If it is necessary to collect and release the first and second cables: Adopt the excitation method in the linear growth mode to drive the screw tube in the second piezoelectric drive trolley to move towards the first piezoelectric drive trolley until the screw tube in the first piezoelectric drive trolley simultaneously pushes the push rods of the first and second rods to press the first cable and the second cable against the roller shaft of the first roller of the second wheel set and the drum of the second wheel set respectively; If it is necessary to collect and release the first cable, the first piezoelectric drive trolley shall perform the following steps: Apply the first and second electrical signals to the first and third piezoelectric ceramic sheets respectively, and apply the third electrical signal to the second and fourth piezoelectric ceramic sheets simultaneously; the first to third electrical signals are all AC harmonic electrical signals; the second electrical signal is delayed by π in the time phase compared with the first electrical signal; the third electrical signal is delayed by π / 2 in the time phase compared with the first electrical signal; under the excitation of the electrical signal, the first-order longitudinal vibration and the third-order bending vibration modes are simultaneously excited on the piezoelectric vibrator, and a micro-amplitude elliptical vibration perpendicular to the z-axis is coupled on the first driving surface. The frictional force drives the roller to rotate, thereby driving the first cable to generate a linear motion along the y direction; if it is necessary to change the linear motion direction of the first cable, keep the phase difference between the first and second electrical signals unchanged, and make the third electrical signal advance by π / 2 in the time phase compared with the first electrical signal; If it is necessary to collect and release the second cable, the first piezoelectric drive trolley shall perform the following steps: Apply the first and second electrical signals to the second and fourth piezoelectric ceramic sheets respectively, and apply the third electrical signal to the first and third piezoelectric ceramic sheets simultaneously; the first to third electrical signals are all AC harmonic electrical signals; the second electrical signal is delayed by π in the time phase compared with the first electrical signal; the third electrical signal is delayed by π / 2 in the time phase compared with the first electrical signal; under the excitation of the electrical signal, the first-order longitudinal vibration and the third-order bending vibration modes are simultaneously excited on the piezoelectric vibrator, and a micro-amplitude elliptical vibration perpendicular to the x-axis is coupled on the second driving surface. The frictional force drives the drum to rotate, thereby driving the second cable to generate a linear motion along the y direction; if it is necessary to change the linear motion direction of the second cable, keep the phase difference between the first and second electrical signals unchanged, and make the third electrical signal advance by π / 2 in the time phase compared with the first electrical signal; Similarly, driving the first and second piezoelectric drive trolleys successively can realize the collection and release of the third and fourth cables:

[0009] Compared with the prior art, the present invention adopts the above technical solutions and has the following technical effects: 1. The lap-generated pipeline is self-growing and can actively adapt to the intestinal path. There is no risk of damaging the intestinal wall when laying the pipeline; 2. Give full play to the advantages of multi-modal and multi-mode piezoelectric drive technology, and use a single piezoelectric drive mechanism to simultaneously realize the laying of pipelines and the retraction and extension of diagnostic and therapeutic instruments, with a simple and compact structure; BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 is a schematic structural diagram of the present invention; Figure 2 is a schematic structural diagram of the spiral overlapping mechanism in the present invention; Figure 3 is a schematic structural diagram of the piezoelectric drive mechanism in the present invention; Figure 4 is a schematic structural diagram of the piezoelectric drive trolley in the present invention; Figure 5 is a schematic structural diagram of the piezoelectric vibrator in the present invention; Figure 6 is an assembly schematic diagram of the threaded pipe and the two-degree-of-freedom hinge mechanism in the present invention; Figure 7 is a schematic structural diagram of the first and second wheel sets in the piezoelectric drive trolley of the present invention; Figure 8 is a schematic structural diagram of the first to fourth levers in the present invention; Figure 9 is a schematic structural diagram of the support for diagnostic and therapeutic instruments in the present invention; Figure 10 is a schematic diagram of the electrical signal application when the piezoelectric vibrator drives the threaded pipe in the present invention; Figure 11 is a schematic diagram of the two spatially orthogonal first-order bending vibration coupling modes of the piezoelectric vibrator in the present invention; Figure 12 is a working principle diagram of the robot driving the solenoid to grow linearly in the present invention; Figure 13 is a working principle diagram of the robot driving the solenoid to grow bendedly in the present invention; Figure 14 is a schematic diagram of the steps of the solenoid growing bendedly in the present invention; Figure 15 is a schematic diagram of the electrical signal application when the piezoelectric vibrator retracts and extends the diagnostic and therapeutic instruments in the present invention; Figure 16 is a schematic diagram of the first-order longitudinal vibration and third-order bending vibration coupling modes of the piezoelectric vibrator in the present invention; Figure 17 is a working principle diagram of the robot retracting and extending the first cable in the diagnostic and therapeutic instruments in the present invention; Figure 18 is a working principle diagram of the robot retracting and extending the second cable in the diagnostic and therapeutic instruments in the present invention;

[0011] In the figure, 1 is a spiral lapping mechanism, 2 is a piezoelectric driving mechanism, 3.1 is the first cable of the diagnostic and therapeutic instrument, 3.2 is the second cable of the diagnostic and therapeutic instrument, 3.3 is the third cable of the diagnostic and therapeutic instrument, 3.4 is the fourth cable of the diagnostic and therapeutic instrument, 1.1 is a spiral lapping belt, 1.2 is a lapping guide rail, 1.3 is a guide rail seat, 2.1 is the first piezoelectric driving trolley, 2.2 is the second piezoelectric driving trolley, 2.3 is a two-degree-of-freedom hinge mechanism, 2.4 is a support for the diagnostic and therapeutic instrument, 2.5 is the first lever, 2.6 is the second lever, 2-7 is the third lever, 2.8 is the fourth lever, 2.1.1 is a piezoelectric vibrator, 2.1.2 is the threaded tube of the first piezoelectric driving trolley, 2.2.2 is the threaded tube of the second piezoelectric driving trolley, 2.1.3 is the first wheel set, 2.1.4 is the second wheel set, 2.1.1.1 is a metal matrix, 2.1.1.2 is the first piezoelectric ceramic sheet, 2.1.1.3 is the second piezoelectric ceramic sheet, 2.1.1.4 is the third piezoelectric ceramic sheet, 2.1.1.5 is the fourth piezoelectric ceramic sheet, 2.3.1 is the first connecting rod, 2.3.2 is the second connecting rod, 2.3.3 is the third connecting rod, 2.3.4 is the fourth connecting rod, 2.3.5 is a connecting ring, 2-3.6 is the first rivet, 2.3.7 is the second rivet, 2.3.8 is the third rivet, 2.3.9 is the fourth rivet, 2.3.10 is the fifth rivet, 2.3.11 is the sixth rivet, 2.3.12 is the seventh rivet, 2.3.13 is the eighth rivet, 2.1.3A is the first roller of the first wheel set, 2.1.3B is the second roller of the first wheel set, 2.1.4A is the first roller of the second wheel set, 2.1.4B is the second roller of the second wheel set, 2.1.3A1 is the first wheel of the first roller of the first wheel set, 2.1.3A2 is the second wheel of the first roller of the first wheel set, 2.1.3A3 is the first hook of the first roller of the first wheel set, 2-1.3A4 is the second hook of the first roller of the first wheel set, 2.1.3C is the first tension spring of the first wheel set, 2.1.3D is the second tension spring of the first wheel set, 2.1.4E is the drum of the second wheel set. Detailed implementation mode

[0012] The technical solution of the present invention will be further described in detail below in conjunction with the accompanying drawings: The present invention can be implemented in many different forms and should not be considered limited to the embodiments described herein. On the contrary, these embodiments are provided so that this disclosure is thorough and complete, and will fully convey the scope of the present invention to those skilled in the art. In the drawings, components are enlarged for clarity.

[0013] As Figure 1 shown, the present invention discloses a piezoelectric-driven self-growing colonoscopy robot, which includes a spiral lapping mechanism, a piezoelectric driving mechanism, and a diagnostic and therapeutic instrument; As Figure 2As shown, the spiral lapping mechanism includes a spiral lapping belt, a lapping guide rail, and a guide rail seat. Among them, the spiral lapping belt is a soft belt with a shuttle-shaped cross-section, and the two side surfaces in the diagonal direction are respectively attached with the hook belt and the plush belt of the nylon fastener; the lapping guide rail is a wire structure formed by bending, with a guiding channel in the middle for the lapping belt to pass through, and annular guiding ends and fixed ends adapted to the cross-sectional shape of the lapping belt are respectively provided at both ends; the fixed end is connected to the guide rail seat; the guide rail seat is a rotating body structure formed by a T-shaped cross-section, with a through hole for passing through the lapping belt in the center, and the cross-sectional shape of the through hole is the same as that of the lapping belt; a fixed groove is provided on the end surface of the larger-diameter side of the guide rail seat for connecting the fixed end of the lapping guide rail; the end surface of the smaller-diameter side of the guide rail seat is the driving surface; the annular surface parallel to the end surface at the shoulder of the guide rail seat is the limiting surface; As Figure 3 shown, the piezoelectric driving mechanism includes first to second piezoelectric driving trolleys, a two-degree-of-freedom hinge mechanism, first to fourth levers, and a medical instrument support. Among them, the first to second piezoelectric driving trolleys have the same structure. As Figure 4 shown, they both include a piezoelectric vibrator, a threaded tube, and first to second wheel sets; The first and second piezoelectric driving trolleys are centrosymmetric about the center of the two-degree-of-freedom hinge mechanism; As Figure 5 shown, the piezoelectric vibrator includes a metal matrix and first to fourth piezoelectric ceramic sheets. Among them, the metal matrix is a hollow cylindrical tube symmetric about the axial symmetry plane, and first to fourth ceramic bonding planes evenly distributed along the circumferential direction are provided at the position of the axial symmetry plane; the metal matrix is provided with first to fourth strip-shaped grooves evenly distributed along the circumferential direction near its first end surface, and first to fourth through holes are respectively provided in the direction perpendicular to the first to fourth strip-shaped grooves. First to fourth driving surfaces are respectively provided at the middle position between every two strip-shaped grooves; the metal matrix is provided with fifth to eighth strip-shaped grooves, fifth to eighth through holes, and fifth to eighth driving surfaces symmetric about the axial symmetry plane near its second end surface with respect to the first to fourth strip-shaped grooves, first to fourth through holes, and first to fourth driving surfaces; an internal thread is provided in the inner hole of the metal matrix to form a threaded fit with the threaded tube; the first to fourth piezoelectric ceramic sheets have the same structure and are respectively pasted on the first to fourth ceramic bonding planes of the metal matrix, and are centrosymmetric about the center of the metal matrix and polarized inward simultaneously along their thickness directions; As Figure 6 shown, the threaded tube is a hollow cylindrical tube provided with an external thread; two extension bosses are provided at the first end surface of the threaded tube, and first to second hinge through holes for hinging with the two-degree-of-freedom hinge mechanism are respectively provided on the sides of the two bosses away from the threaded tube; The internal thread of the piezoelectric vibrator metal substrate and the external thread of the threaded tube in the first piezoelectric driving trolley are coarse-threaded; the internal thread of the piezoelectric vibrator metal substrate and the external thread of the threaded tube in the second piezoelectric driving trolley are fine-threaded, and the helix direction is opposite to that of the aforementioned coarse thread. As Figure 6 shown, the two-degree-of-freedom hinge mechanism includes first to fourth connecting rods, first to eighth rivets, and a connecting ring. Among them, the first to fourth connecting rods have the same structure, and are all rectangular thin plates with chamfers at both ends; the nth connecting rod is respectively provided with 2n + 1 and 2n + 2 hinge through holes at both ends, where n is a natural number greater than or equal to 1 and less than or equal to 4; the connecting ring is a hollow cylinder with four circumferentially evenly distributed planes along the outer circle of the cylindrical surface, and is provided with eleventh to fourteenth hinge through holes whose centroid positions coincide with the centroids of the four planes; the third and fifth hinge through holes of the first and second connecting rods are respectively matched with the first and second hinge through holes of the threaded tube through the first to second rivets; the fourth and sixth hinge through holes of the first and second connecting rods are respectively matched with the eleventh and thirteenth hinge through holes of the connecting ring through the third to fourth rivets; the seventh and ninth hinge through holes of the third and fourth connecting rods are respectively matched with the twelfth and fourteenth hinge through holes of the connecting ring through the fifth to sixth rivets; the eighth and tenth hinge through holes of the third and fourth connecting rods are respectively matched with the first to second hinge through holes of the threaded tube in the second piezoelectric driving trolley through the seventh to eighth rivets: As Figure 7 shown, the first wheel set is a centrosymmetric structure including first to second rollers and first to second tension springs. Among them, the first to second rollers have the same structure, and each includes first to second wheels, a roller shaft, and first to second hooks; the roller shaft is a solid long and thin cylinder with diameters smaller at both ends than in the middle part; the first to second hooks have the same structure, and each includes first to second connection holes; the first to second hooks are symmetrically arranged at both ends of the small-diameter section of the roller shaft with respect to the axial symmetry plane of the roller shaft through their respective first connection holes, and coincide with the shaft shoulders of the roller shaft; the first to second wheels have the same structure, and are both hollow rotating bodies; the first to second wheels are symmetrically arranged on both sides of the first to second hooks, and the inner holes are concentric with the roller shaft; The first to second tension springs have the same structure, and both sides include two hooks; the hooks on both sides of the first tension spring are respectively connected to the second connection holes of the first hooks in the first to second rollers; the hooks on both sides of the second tension spring are respectively connected to the second connection holes of the second hooks in the first to second rollers; The first wheel set is located on the side of the second end face of the metal substrate, where the roller shafts of the first and second rollers are respectively tangent to the fifth and seventh driving surfaces; As Figure 7As shown, the second wheel set includes a first wheel set and a drum; the drum is a hollow thin-walled cylindrical tube, and its inner diameter is the same as the outer diameter of the tension spring; the drum is coaxially fitted with the first tension spring and their geometric centers coincide; The second wheel set is located on the side of the first cross-section of the metal matrix, and the axles of the first and second rollers and the drum are tangent to the first, third, and second drive surfaces respectively; As Figure 8 As shown, the first and third levers have the same structure, both are closed linear structures made of metal wires, and there is only one unique symmetry plane; the first and third levers both include a push rod, a fulcrum, and a cable limiting frame; the projections of the first and third lever structures on the symmetry plane are a curve; the projections of the first and third lever structures on the plane perpendicular to their symmetry plane are a closed curve; The second and fourth levers have the same structure, both are closed linear structures made of metal wires, and there is only one unique symmetry plane; the second and fourth levers both include a push rod, a fulcrum, and a cable limiting frame; the projections of the second and fourth lever structures on the symmetry plane are a curve; the projections of the second and fourth lever structures on the plane perpendicular to their symmetry plane are a closed curve; The first and second levers are installed on the side of the first end face of the piezoelectric oscillator of the first piezoelectric driving trolley: the push rods of the first and second levers point to the side of the second end face of the piezoelectric oscillator of the first piezoelectric driving trolley; the fulcrum of the first lever is fitted with the first through hole of the piezoelectric oscillator of the first piezoelectric driving trolley; the fulcrum of the second lever is fitted with the second through hole of the piezoelectric oscillator of the first piezoelectric driving trolley; The third and fourth levers are installed on the side of the first end face of the piezoelectric oscillator of the second piezoelectric driving trolley; the push rods of the third and fourth levers point to the side of the second end face of the piezoelectric oscillator of the second piezoelectric driving trolley; the fulcrum of the third lever is fitted with the first through hole of the piezoelectric oscillator of the second piezoelectric driving trolley; the fulcrum of the fourth lever is fitted with the second through hole of the piezoelectric oscillator of the second piezoelectric driving trolley; As Figure 1 As shown, the medical device includes the first to fourth cables; the first to fourth cables have the same structure, all are round-section cables, and the head diameter is larger than the rear cable; The cable limiting frames of the first to fourth levers pass through the first to fourth cables respectively; As Figure 9As shown, the medical device support is a spatial linear structure made of wire, including four U-shaped bends and four superior arc frames. Among them, the four superior arc frames of the medical device support are respectively matched with the shoulders at the variable cross-section of the first to fourth cable heads; the four U-shaped bends of the medical device support are respectively matched with the first to fourth strip grooves of the piezoelectric oscillator metal matrix of the first piezoelectric driving trolley and fit to the bottom of the grooves;

[0014] The present invention also discloses a linear growth working mode of a piezoelectric-driven self-growing colonoscopy robot, including the following steps: If it is necessary to drive the first piezoelectric driving trolley: As Figure 10 shown, the first to fourth electric signals are respectively applied to the first to fourth piezoelectric ceramic chips of the first piezoelectric driving trolley; the first to fourth electric signals are all AC harmonic signals, and the first to third electric signals are respectively π / 2 ahead of the second to fourth electric signals in time. The first to fourth electric signals simultaneously excite the first-order bending vibration modes of the piezoelectric oscillator in two spatially orthogonal directions. Through the coupling of the two modes, micro-amplitude elliptical vibration trajectories as shown in Figure 11 are formed on the surface particles of the internal thread of the piezoelectric oscillator, and the threaded tube is driven to rotate through the frictional action; if it is necessary to drive the threaded tube to rotate in the reverse direction, the first to third electric signals are respectively delayed by π / 2 compared with the second to fourth electric signals in time; If it is necessary to drive the second piezoelectric driving trolley, the electric signal application method is the same as that when driving the first piezoelectric driving trolley; As Figure 12 shown, when driving the second piezoelectric driving trolley, the threaded tube generates a combined rotational and linear motion. Since the piezoelectric oscillator in the first piezoelectric driving trolley does not vibrate and the wheel set is in a friction self-locking state, the first piezoelectric driving trolley remains stationary; the linear motion of the screw in the second piezoelectric driving trolley pushes the guide rail seat away from the piezoelectric oscillator and transmits the combined rotational and linear motion to the overlapping guide rail, guiding the spiral overlapping belt to spiral overlap from the inside of the solenoid, forming the self-growth of the solenoid; After growing a certain distance, drive the first piezoelectric driving trolley to reverse the rotation of the threaded tube and disconnect it from the guide rail seat, and at the same time make the piezoelectric oscillator in the first piezoelectric driving trolley generate a forward linear displacement; By alternately performing the above two drives, continuous linear growth of the solenoid can be achieved;

[0015] The present invention also discloses a bending growth working mode of a piezoelectric-driven self-growing colonoscopy robot, including the following steps: In the bending growth working mode, the driving methods of the first and second piezoelectric driving trolleys are the same as those in the linear growth mode; As Figure 13As shown, the threaded tube in the second piezoelectric driving cart is driven to generate a combined rotational and linear motion. Since the piezoelectric vibrator in the first piezoelectric driving cart does not vibrate and the wheel set is in a friction self-locking state, the first piezoelectric driving cart remains stationary. The linear motion of the screw in the second piezoelectric driving cart pushes the guide rail base away from the piezoelectric vibrator and transfers the combined rotational and linear motion to the overlapping guide rail, guiding the spiral overlapping belt to spiral overlap from the inside of the solenoid, forming the self-growth of the solenoid. After the threaded tube rotates 180 degrees, the threaded tube in the first piezoelectric driving cart is driven to rotate in the same direction, transferring the rotational motion in the same direction and the linear motion in the opposite direction to the overlapping guide rail, causing the overlapping belt to generate an axial retraction while maintaining the spiral overlap, forming the bending of the neutral axis of the solenoid. As Figure 14 shown, by repeating the above two drives, the bending growth of the linear solenoid can be achieved.

[0016] The present invention also discloses a working mode for the collection and release of the diagnostic and therapeutic instruments of a piezoelectric-driven self-growing colonoscopy robot, which includes the following steps: If it is necessary to collect and release the first and second cables: Adopt the excitation method described in the linear growth working mode to drive the threaded tube in the second piezoelectric driving cart to move towards the first piezoelectric driving cart until the threaded tube in the first piezoelectric driving cart simultaneously pushes the push rods of the first and second rods to press the first cable and the second cable against the roller shaft of the first roller of the second wheel set and the drum of the second wheel set respectively. If it is necessary to collect and release the first cable, the first piezoelectric driving cart is operated according to the following steps: As Figure 15 shown, the first and third piezoelectric ceramic sheets are respectively applied with the first and second electrical signals, and the second and fourth piezoelectric ceramic sheets are simultaneously applied with the third electrical signal; the first to third electrical signals are all AC harmonic electrical signals; the second electrical signal is delayed by π in the time phase compared with the first electrical signal; the third electrical signal is delayed by π / 2 in the time phase compared with the first electrical signal: under the excitation of the electrical signal, a first-order longitudinal vibration and a third-order bending vibration mode are simultaneously excited on the piezoelectric vibrator, and a micro-amplitude elliptical vibration perpendicular to the z-axis as shown in Figure 16 shown is coupled on the first driving surface, and the friction drives the roller to rotate, thereby driving the first cable to generate a linear motion along the y direction, as shown in Figure 17 shown; if it is necessary to change the linear motion direction of the first cable, keep the phase difference between the first and second electrical signals unchanged, and make the third electrical signal advance by π / 2 in the time phase compared with the first electrical signal. If it is necessary to collect and release the second cable, the first piezoelectric driving cart is operated according to the following steps: Apply the first and second electrical signals to the second and fourth piezoelectric ceramic sheets respectively, and apply the third electrical signal to the first and third piezoelectric ceramic sheets simultaneously; the first to third electrical signals are all AC harmonic electrical signals; the second electrical signal is delayed by π in time phase with respect to the first electrical signal; the third electrical signal is delayed by π / 2 in time phase with respect to the first electrical signal; under the excitation of the electrical signals, a first-order longitudinal vibration and a third-order bending vibration mode are simultaneously excited on the piezoelectric vibrator, and a small-amplitude elliptical vibration perpendicular to the x-axis is coupled on the second driving surface, and the frictional force drives the roller to rotate, thereby driving the second cable to generate a linear motion along the y direction, as Figure 18 shown; if it is necessary to change the linear motion direction of the second cable, keep the phase difference between the first and second electrical signals unchanged, and make the third electrical signal advance by π / 2 in time phase with respect to the first electrical signal; Similarly, driving the first and second piezoelectric driving carts successively can realize the winding and unwinding of the third and fourth cables;

[0017] Those skilled in the art of this technology can understand that, unless otherwise defined, all terms (including technical terms and scientific terms) used here have the same meaning as the general understanding of those of ordinary skill in the field to which the present invention belongs. It should also be understood that terms such as those defined in a general dictionary should be understood to have a meaning consistent with the meaning in the context of the prior art, and will not be interpreted with an idealized or overly formal meaning unless defined as here.

[0018] The specific embodiments described above have further elaborated on the purpose, technical solutions, and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A piezoelectrically driven self-growing colonoscopy robot, characterized in that, It includes a spiral lap mechanism, a piezoelectric drive mechanism, and a diagnostic and treatment device; The spiral lap mechanism comprises a spiral lap belt, a lap guide rail and a guide rail seat, wherein the spiral lap belt is a soft belt with a shuttle-shaped cross-section, and its two diagonal side surfaces are respectively attached with a hook belt and a velvet belt of a Velcro; the lap guide rail is a bent steel wire structure, with a guide channel for the lap belt to pass through in the middle, and an annular guide end and a fixed end adapted to the cross-sectional shape of the lap belt at both ends; the fixed end is connected to the guide rail seat; the guide rail seat is a rotating body structure formed by a T-shaped cross-section, a through hole for passing the lap belt in the center, and the cross-sectional shape of the through hole is consistent with the cross-sectional shape of the lap belt; the end face of the guide rail seat on the side with a larger diameter is provided with a fixing groove for connecting the fixed end of the lap guide rail; the end face of the guide rail seat on the side with a smaller diameter is a driving surface; the annular surface parallel to the end face at the shoulder of the guide rail seat is a limiting surface; The piezoelectric drive mechanism includes first and second piezoelectric drive trolleys, a two-degree-of-freedom hinge mechanism, first to fourth levers, and a diagnostic and treatment instrument support, wherein the first and second piezoelectric drive trolleys have the same structure and both include a piezoelectric vibrator, a threaded tube, and first to second wheel sets; The first and second piezoelectric driven carriages are centrally symmetrical about the center of the two-degree-of-freedom hinge mechanism; The piezoelectric vibrator includes a metal substrate and first to fourth piezoelectric ceramic sheets, wherein the metal substrate is a hollow cylindrical tube symmetrical about an axial symmetry plane, and the axial symmetry plane is provided with first to fourth ceramic bonding planes uniformly distributed along the circumference; the metal substrate is provided with first to fourth strip grooves uniformly distributed along the circumference near its first end surface, and first to fourth through holes are respectively provided in a direction perpendicular to the first to fourth strip grooves, and first to fourth driving surfaces are respectively provided between every two strip grooves; the metal substrate is provided with fifth to eighth strip grooves, fifth to eighth through holes, and fifth to eighth driving surfaces respectively symmetrical with the first to fourth strip grooves, the first to fourth through holes, and the first to fourth driving surfaces about the axial symmetry plane near its second end surface; the inner hole of the metal substrate is provided with an internal thread to form a threaded fit with the threaded tube; the first to fourth piezoelectric ceramic sheets have the same structure and are respectively adhered to the first to fourth ceramic bonding planes of the metal substrate, and are centrally symmetrical about the center of the metal substrate and are simultaneously polarized inward along the thickness direction of the metal substrate; The threaded tube is a hollow cylindrical tube with an external thread; two extended bosses are provided on the first end surface of the threaded tube, and the two bosses are provided with first and second hinged through holes for hinged connection with a two-degree-of-freedom hinge mechanism on the side away from the threaded tube; The internal thread of the metal substrate of the piezoelectric vibrator and the external thread of the threaded tube in the first piezoelectric driving trolley are coarse threads; the internal thread of the metal substrate of the piezoelectric vibrator and the external thread of the threaded tube in the second piezoelectric driving trolley are fine threads, and the direction of rotation is opposite to that of the coarse threads; The two-degree-of-freedom hinge mechanism includes first to fourth linkages, first to eighth rivets, and a connecting ring. Among them, the first to fourth linkages have the same structure, which are all rectangular thin plates with chamfers at both ends; each of the nth linkages is provided with 2n + 1 and 2n + 2 articulated through-holes at both ends, where n is a natural number greater than or equal to 1 and less than or equal to 4; the connecting ring is a hollow cylinder with four circumferentially evenly distributed planes along the outer circumference of the cylindrical surface, and is provided with eleventh to fourteenth articulated through-holes whose centroid positions coincide with the centroids of the four planes; the third and fifth articulated through-holes of the first and second linkages are respectively matched with the first and second articulated through-holes of the threaded tube through the first to second rivets; the fourth and sixth articulated through-holes of the first and second linkages are respectively matched with the eleventh and thirteenth articulated through-holes of the connecting ring through the third to fourth rivets; the seventh and ninth articulated through-holes of the third and fourth linkages are respectively matched with the twelfth and fourteenth articulated through-holes of the connecting ring through the fifth to sixth rivets; the eighth and tenth articulated through-holes of the third and fourth linkages are respectively matched with the first and second articulated through-holes of the threaded tube in the second piezoelectric drive trolley through the seventh to eighth rivets; The first wheel set is a centrosymmetric structure including first to second rollers and first to second tension springs. Among them, the first to second rollers have the same structure, each including first to second wheels, a roller shaft, and first to second hooks; the roller shaft is a solid long and thin cylinder with diameters smaller at both ends than in the middle part; the first to second hooks have the same structure, each including first to second connection holes; the first to second hooks are symmetrically arranged at both ends of the small-diameter section of the roller shaft with respect to the axial symmetry plane of the roller shaft through their respective first connection holes, and coincide with the shaft shoulders of the roller shaft; the first to second wheels have the same structure, which are all hollow rotating bodies; the first to second wheels are symmetrically arranged on both sides of the first to second hooks, and the inner holes are concentric with the roller shaft; The first to second tension springs have the same structure, and both sides include two hooks; the hooks on both sides of the first tension spring are respectively connected to the second connection holes of the first hooks in the first to second rollers; the hooks on both sides of the second tension spring are respectively connected to the second connection holes of the second hooks in the first to second rollers; The first wheel set is located on the side of the second end face of the metal matrix, where the roller shafts of the first and second rollers are respectively tangent to the fifth and seventh driving surfaces; The second wheel set includes the first wheel set and a drum; the drum is a hollow thin-walled cylindrical tube, and its inner diameter is the same as the outer diameter of the tension spring; the drum is coaxially fitted with the first tension spring and their geometric centers coincide; The second wheel set is located on the side of the first cross-section of the metal matrix, where the roller shafts of the first and second rollers and the drum are respectively tangent to the first, third, and second driving surfaces; The first and third levers have the same structure, which are both closed linear structures made of metal wires and have only a unique symmetry plane; the first and third levers both include a push rod, a fulcrum, and a cable limiting frame; the projections of the first and third lever structures on the symmetry plane are a curve; the projections of the first and third lever structures on the plane perpendicular to their symmetry plane are a closed curve; The second and fourth levers have the same structure, both being closed linear structures made of wire and having only a single plane of symmetry; the second and fourth levers each include a push rod, a fulcrum, and a cable limiting frame; the projections of the second and fourth lever structures on the plane of symmetry are a curve; the projections of the second and fourth lever structures on a plane perpendicular to their plane of symmetry are a closed curve; The first and second levers are installed on the first end face side of the metal substrate of the piezoelectric vibrator of the first piezoelectric driving trolley; the push rods of the first and second levers point to the second end face side of the metal substrate of the piezoelectric vibrator of the first piezoelectric driving trolley; the fulcrum of the first lever is fitted with the first through hole of the metal substrate of the piezoelectric vibrator of the first piezoelectric driving trolley; the fulcrum of the second lever is fitted with the second through hole of the metal substrate of the piezoelectric vibrator of the first piezoelectric driving trolley; The third and fourth levers are installed on the first end face side of the metal substrate of the piezoelectric vibrator of the second piezoelectric driving trolley; the push rods of the third and fourth levers point to the second end face side of the metal substrate of the piezoelectric vibrator of the second piezoelectric driving trolley; the fulcrum of the third lever is fitted with the first through hole of the metal substrate of the piezoelectric vibrator of the second piezoelectric driving trolley; the fulcrum of the fourth lever is fitted with the second through hole of the metal substrate of the piezoelectric vibrator of the second piezoelectric driving trolley; The medical instrument includes first to fourth cables; the first to fourth cables have the same structure, all being circular cross-section cables, and the head diameter is larger than the rear cable; The cable limiting frames of the first to fourth levers respectively pass through the first to fourth cables; The support of the medical instrument is a space linear structure made of wire, including four U-shaped bends and four superior arc frames. Among them, the four superior arc frames of the support of the medical instrument are respectively fitted with the shoulders at the variable cross-section of the heads of the first to fourth cables; the four U-shaped bends of the support of the medical instrument are respectively fitted with and adhere to the bottoms of the first to fourth strip-shaped grooves of the metal substrate of the piezoelectric vibrator of the first piezoelectric driving trolley.

2. The linear growth working mode of the piezoelectric-driven self-growing colonoscopy robot according to claim 1, characterized in that, It includes the following steps: If it is necessary to drive the first piezoelectric driving trolley: Apply first to fourth electrical signals to the first to fourth piezoelectric ceramic chips of the first piezoelectric driving trolley respectively; the first to fourth electrical signals are all AC harmonic signals, and the first to third electrical signals are respectively ahead of the second to fourth electrical signals by π / 2 in time. The first to fourth electrical signals simultaneously excite the first-order bending vibration modes of the piezoelectric vibrator in two spatially orthogonal directions. Through the coupling of the two modes, a micro-amplitude elliptical vibration trajectory is formed by the particles on the inner thread surface of the piezoelectric vibrator, and the threaded tube is driven to rotate through the friction effect; if it is necessary to drive the threaded tube to rotate in the reverse direction, make the first to third electrical signals be respectively delayed by π / 2 compared with the second to fourth electrical signals in time; If it is necessary to drive the second piezoelectric driving trolley, the way of applying electrical signals is the same as when driving the first piezoelectric driving trolley; When driving the second piezoelectric driving trolley, the threaded tube generates a combined rotational and linear motion. Since the piezoelectric vibrator in the first piezoelectric driving trolley does not vibrate and the wheel set is in a friction self-locking state, the first piezoelectric driving trolley remains stationary. The linear motion of the screw in the second piezoelectric driving trolley pushes the guide rail seat away from the piezoelectric vibrator and transfers the combined rotational and linear motion to the overlapping guide rail, guiding the spiral overlapping belt to spiral overlap from the inside of the solenoid, forming the self-growth of the solenoid. After growing a certain distance, drive the first piezoelectric driving trolley to reverse the rotation of the threaded tube and disconnect it from the guide rail seat. At the same time, make the piezoelectric vibrator in the first piezoelectric driving trolley generate a forward linear displacement. By alternately performing the above two drives, continuous linear growth of the solenoid can be achieved.

3. The bending growth working mode of the piezoelectric-driven self-growing colonoscopy robot according to claim 1, characterized in that, It includes the following steps: In the bending growth working mode, the driving methods for the first and second piezoelectric driving trolleys are the same as those in claim 2. When driving the threaded tube in the second piezoelectric driving trolley to generate a combined rotational and linear motion, since the piezoelectric vibrator in the first piezoelectric driving trolley does not vibrate and the wheel set is in a friction self-locking state, the first piezoelectric driving trolley remains stationary. The linear motion of the screw in the second piezoelectric driving trolley pushes the guide rail seat away from the piezoelectric vibrator and transfers the combined rotational and linear motion to the overlapping guide rail, guiding the spiral overlapping belt to spiral overlap from the inside of the solenoid, forming the self-growth of the solenoid. After the threaded tube rotates 180 degrees, switch to driving the threaded tube in the first piezoelectric driving trolley to rotate in the same direction, transfer the same-direction rotational motion and the reverse linear motion to the overlapping guide rail, so that the overlapping belt generates an axial retraction while maintaining spiral overlap, forming the bending of the neutral axis of the solenoid. By repeating the above two drives, the bending growth of the linear solenoid can be achieved.

4. The working mode of the diagnostic and therapeutic instrument retraction and extension of the piezoelectric-driven self-growing colonoscopy robot according to claim 1, wherein, It includes the following steps: If it is necessary to wind and unwind the first and second cables: Adopt the excitation method described in claim 2 to drive the threaded tube in the second piezoelectric driving trolley to move towards the first piezoelectric driving trolley until the threaded tube in the first piezoelectric driving trolley simultaneously pushes the push rods of the first and second rods to press the first cable and the second cable against the roller shaft of the first roller of the second wheel set and the drum of the second wheel set respectively. If it is necessary to wind and unwind the first cable, for the first piezoelectric driving trolley, follow the steps below: Apply the first and second electrical signals to the first and third piezoelectric ceramic sheets respectively, and apply the third electrical signal to the second and fourth piezoelectric ceramic sheets simultaneously. The first to third electrical signals are all AC harmonic electrical signals. The second electrical signal is delayed by π in time phase compared with the first electrical signal. The third electrical signal is delayed by π / 2 in time phase compared with the first electrical signal. Under the excitation of the electrical signal, a first-order longitudinal vibration mode and a third-order bending vibration mode are simultaneously excited on the piezoelectric vibrator, and a micro-amplitude elliptical vibration perpendicular to the z-axis is coupled on the first driving surface. The frictional force drives the roller to rotate, thereby driving the first cable to generate a linear motion along the y direction. If it is necessary to change the linear motion direction of the first cable, keep the phase difference between the first and second electrical signals unchanged, and make the third electrical signal advance by π / 2 in time phase compared with the first electrical signal. If it is necessary to wind and unwind the second cable, for the first piezoelectric driving trolley, follow the steps below: Apply the first and second electrical signals to the second and fourth piezoelectric ceramic sheets respectively, and apply the third electrical signal to the first and third piezoelectric ceramic sheets simultaneously; the first to third electrical signals are all AC harmonic electrical signals; the second electrical signal is delayed by π in the time phase compared to the first electrical signal; the third electrical signal is delayed by π / 2 in the time phase compared to the first electrical signal; under the excitation of the electrical signals, a first-order longitudinal vibration and a third-order bending vibration mode are simultaneously excited on the piezoelectric vibrator, and a small-amplitude elliptical vibration perpendicular to the x-axis is coupled on the second driving surface, and the frictional force drives the roller to rotate, thereby driving the second cable to generate a linear motion along the y direction; If it is necessary to change the linear motion direction of the second cable, keep the phase difference between the first and second electrical signals unchanged, and make the third electrical signal advance by π / 2 in the time phase compared to the first electrical signal; Similarly, driving the first and second piezoelectric drive carts successively can realize the winding and unwinding of the third and fourth cables.

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