Whole-course active deformation intestinal robot based on corrugated pipe and driving method of whole-course active deformation intestinal robot

Abstract

The invention provides a whole-course active deformation intestinal robot based on a corrugated pipe and a driving method of the whole-course active deformation intestinal robot. The whole-course active deformation intestinal robot comprises a first trolley, a second trolley, a trolley connecting part and a bending part, the bent part comprises a corrugated pipe; the first trolley comprises a first piezoelectric vibrator, a first screw rod, a first crawling mechanism and a second crawling mechanism; the second trolley and the first trolley are the same in structure; the trolley connecting part comprises first to fourth connecting rods, a rivet and a connecting ring. The whole-course active deformation intestinal robot based on the corrugated pipe is simple in structure, and whole-course active bending of the whole structure can be achieved.

Description

Technical Field

[0001] The present invention relates to the fields of piezoelectric drive technology and medical robots, and particularly to a whole-course actively deformable intestinal robot based on a bellows and a driving method thereof. Background Art

[0002] In the medical field, minimally invasive surgery and colonoscopy instruments are important research directions in various countries. Minimally invasive surgery robots and colonoscope robots are widely used for the examination and treatment of colon diseases. Currently, the working section of minimally invasive surgery robots and colonoscopies mainly uses a cable drive or a pneumatic drive to achieve multi-degree-of-freedom movement, but the rear-end delivery tube can only be passively deformed. This delivery method will cause great pain to patients and may even damage the colon.

[0003] The whole-course actively deformable intestinal robot based on a bellows can achieve the whole-course active bending of the bellows through a piezoelectric drive. Compared with the current passive deformation method, it has the advantages of whole-course active deformation, does not require a complex transmission mechanism, has a simpler structure, and higher precision. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a whole-course actively deformable intestinal robot based on a bellows and a driving method thereof in view of the defects involved in the background art.

[0005] The present invention adopts the following technical solutions to solve the above technical problems: A whole-course actively deformable intestinal robot based on a bellows includes first to second trolleys (1-2), a trolley connection part (3), and a bending part (4); The bending part includes a bellows; The first trolley (1) includes a first piezoelectric vibrator (1.3), a first screw (1.4), and first to second crawling mechanisms (1.1 - 1.2); the first piezoelectric vibrator (1.3) includes a first stator (1.3.5) and first to fourth piezoelectric ceramics (1.3.1 - 1.3.4), the first stator (1.3.5) is a cylindrical thin-walled structure, and four centrally symmetric grooves are evenly arranged along the circumference in the middle of the outer surface of the first stator (1.3.5); the first to fourth piezoelectric ceramics (1.3.1 - 1.3.4) are bonded in the grooves in the middle of the first stator (1.3.5), and the polarization directions of the first to fourth piezoelectric ceramics (1.3.1 - 1.3.4) all point to the first stator (1.3.5) along the ceramic thickness direction; four centrally symmetric grooves are evenly arranged along the circumference at both ends of the first stator (1.3.5); internal threads are provided on the inner wall of the first stator for threaded connection with the first screw (1.4); the first screw is a cylindrical threaded rod; one end of the first screw (1.4) is provided with two bosses, and through holes are provided on the sides of the bosses away from the screw center for connection with the trolley connection part (3); the first screw (1.4) is hollow for passing medical devices; with the axial direction of the first stator as the reference, the direction from the outside of the first stator to the center is defined as the positive direction of the x-axis, and the direction perpendicular to the x-axis and upward is defined as the positive direction of the y-axis; The first crawling mechanism (1.1) includes a roller group and a tension spring (1.1.3); the roller group includes rollers (1.1.2) and roller shafts (1.1.1); the middle structure of the roller (1.1.2) is a cylinder, and the two ends are frustum cones, and the center of the roller (1.1.2) is a through hole; the roller shaft (1.1.1) is a cylinder, and the two ends are hemispheres, and holes are drilled at the centers of the hemispheres on both sides, and the roller shaft (1.1.1) is placed at the center through hole of the roller (1.1.2); the center of the tension spring (1.1.3) is a spring, and the two ends are connection hooks; the connection hooks on both sides of the tension spring are connected to the holes on both sides of the roller shaft (1.1.1); each crawling mechanism (1.1) is composed of four roller groups and four tension springs (1.1.3), and a pre-pressure towards the center direction of the first stator (1.3.5) is applied to the four roller groups through the tension of the tension spring (1.1.3), so that the rollers (1.1.2) are in contact with the grooves at both ends of the first stator (1.3.5); The trolley connection part (3) includes the first to fourth connecting rods (3.1 - 3.4), rivets (3.5) and a connection ring (3.6); the first to fourth connecting rods (3.1 - 3.4) are plate-shaped cuboids with semi-circular plates at both ends, and holes are drilled at the centers of the semi-circular plates at both ends; the connection ring (3.6) is a circular ring structure, and four through holes symmetrically distributed along the center are evenly arranged on the outer ring of the circular ring; one end of the first to fourth connecting rods (3.1 - 3.4) is hinged to the through holes of the connection ring (3.6) through rivets (3.5), and the other end is hinged to the through holes on the convex platform of the screw through rivets (3.5); in this way, the first to second trolleys are connected together; The structure of the second trolley (2) is the same as that of the first trolley (2); the thread rotation directions of the first screw (1.4) and the second screw (2.1), and the first stator (1.3) and the second stator (2.2) are opposite; The trolley connection part (3) can achieve bending with two degrees of freedom, and the trolley connection part (3) can transfer bending moment. When the piezoelectric drive part bends, the torque can still be transferred to another screw to make it rotate around the x-axis; Blades are provided at both ends of the roller (1.1.2), and the blades are placed in the gaps between the bellows nodes, in this way, the first to second trolleys (1 - 2), the trolley connection part (3) and the bending part (4) are connected; The first to second stators and the first to second screws are made of metal materials; the bellows is made of a flexible material;

[0006] The present invention also discloses a piezoelectric drive implementation method for stretching and compression of a full-course actively deformable intestinal robot based on a bellows, which is characterized by including the following steps: Tensile and contraction movements of the corrugated pipe: Taking the first trolley as an example, a sawtooth wave voltage is used to excite the first to fourth piezoelectric ceramics (1.3.1 - 1.3.4); the two-phase electrical signals have the same phase, exciting the first-order longitudinal vibration mode of the first stator (1.3.5), and the first stator (1.3.5) is in the first-order longitudinal vibration working mode with different reciprocating speeds; due to the different reciprocating vibration speeds, the rollers pressed against both ends of the first stator (1.3.5) by the tension spring are affected by frictions with different friction factors. The hypotenuse of the sawtooth wave corresponds to static friction, and the straight edge of the sawtooth wave corresponds to dynamic friction, converting between static friction and dynamic friction, making the two rollers (1.1.2) on the same side rotate in opposite directions, and the rollers (1.1.2) on both sides opposite to each other rotate in opposite directions; if the corrugated pipe is to be stretched, only a sawtooth wave electrical signal with a straight edge first and then a hypotenuse needs to be applied, then the rollers (1.1.2) are first affected by dynamic friction and then static friction, enabling the rollers (1.1.2) to rotate towards both ends of the first stator (1.3.5), and the blades at the gaps between nodes drive the corrugated pipe to make a tensile movement; if the corrugated pipe is to be compressed, only a sawtooth wave electrical signal with a hypotenuse first and then a straight edge needs to be applied, enabling the rollers (1.1.2) to rotate towards the center of the first stator (1.3.5), and the blades drive the corrugated pipe to make a compression movement; the principle of the second trolley (2) driving the tensile and contraction movements of the corrugated pipe is the same as that of the first trolley;

[0007] The present invention also discloses a piezoelectric drive implementation method for the bending of a full-course actively deformable intestinal robot based on a corrugated pipe, which is characterized by including the following steps: Piezoelectric drive implementation method for the bending of the corrugated pipe along the z-axis: Taking the first trolley as an example, a sinusoidal alternating current electrical signal is used to excite the first piezoelectric ceramic (1.3.1) and the third piezoelectric ceramic (1.3.3), and a cosine alternating current is used to excite the second piezoelectric ceramic (1.3.2) and the fourth piezoelectric ceramic (1.3.4); the phase difference between the two-phase electrical signals is π / 2, exciting the first-order longitudinal vibration and the third-order bending vibration along the z-axis direction; the third-order bending vibration mode and the first-order longitudinal vibration mode of the piezoelectric vibrator are coupled, generating a small-amplitude elliptical motion of the surface particles in contact with the rollers (1.1.2), and driving the rollers (1.1.2) to rotate through friction. The rollers (1.1.2) on the same side of the first stator (1.3.5) rotate in opposite directions, and the rollers (1.1.2) on both sides opposite to each other of the first stator (1.3.5) rotate in the same direction, causing the corrugated pipe on one side of the first stator (1.3.5) to contract and the corrugated pipe on the other side to stretch, thus forming a bending movement along the z-axis direction; if the corrugated pipe is to be bent in the opposite direction, a cosine alternating current is used to excite the first piezoelectric ceramic (1.3.1) and the third piezoelectric ceramic (1.3.3), and a sinusoidal alternating current is used to excite the second piezoelectric ceramic (1.3.2) and the fourth piezoelectric ceramic (1.3.4) so that the rotation direction of the rollers (1.1.2) is opposite to the original direction; Piezoelectric drive realizes the bending motion of the bellows along the y-axis: A sinusoidal alternating current signal is used to excite the first piezoelectric ceramic (1.3.1) and the third piezoelectric ceramic (1.3.3), and a cosine alternating current is used to excite the second piezoelectric ceramic (1.3.2) and the fourth piezoelectric ceramic (1.3.4); the phase difference between the two-phase electrical signals is π / 2, exciting the third-order bending vibration mode and the first-order longitudinal vibration mode that bends along the y-axis direction. The third-order bending vibration mode and the first-order longitudinal vibration mode are coupled to form an elliptical motion to drive the roller (1.1.2) to rotate, thereby realizing the bending motion along the y-axis direction;

[0008] The present invention also discloses a piezoelectric drive implementation method for the inchworm-like linear motion of a fully active deformable intestinal robot based on a bellows, which is characterized by including the following steps: The first to second carts (1-2) and the cart connection part (3) realize inchworm-like linear motion: A sinusoidal alternating current signal is used to excite the first piezoelectric ceramic (1.3.1) and the third piezoelectric ceramic (1.3.3), and a cosine alternating current is used to excite the second piezoelectric ceramic (1.3.2) and the fourth piezoelectric ceramic (1.3.4); the phase difference between the two-phase electrical signals is π / 2, exciting the first-order bending vibration that bends along the y-axis direction of the piezoelectric vibrator and the first-order bending vibration that bends along the z-axis direction. The first-order bending vibration modes in two orthogonal directions are coupled to form an elliptical motion, driving the first screw rod (1.4) to generate rotation and linear motion; by changing the order of the voltages applied to the four piezoelectric ceramic sheets, the first screw rod (1.4) can perform reverse rotation and reverse linear motion; when the first piezoelectric vibrator (1.3) vibrates, driving the first screw rod (1.4) to rotate, since the second piezoelectric vibrator (2.2) does not vibrate, the roller (1.1.2) thereon is in a self-locking state and will not roll. Due to the small friction of the roller (1.1.2) on the first piezoelectric vibrator (1.3), it can move along the bellows. The rotation of the first screw rod (1.4) drives the second screw rod (2.1) to rotate, causing the second screw rod (2.1) to screw out from the second piezoelectric vibrator (2.2), and the first screw rod (1.4) pushes the vibrating first piezoelectric vibrator (1.3) to perform linear motion; subsequently, the first piezoelectric vibrator (1.3) is made not to vibrate, and the second piezoelectric vibrator (2.2) vibrates. The second screw rod (2.1) drives the first screw rod (1.4) to rotate, causing the first screw rod (1.4) to screw into the first piezoelectric vibrator (1.3), and the second screw rod (2.1) pulls the second piezoelectric vibrator (2.2) to perform linear motion; alternately applying electrical signals to the two piezoelectric vibrators can realize the inchworm motion of the first to second carts (1-2) and the cart connection part (3) along the bellows;

[0009] The present invention also discloses the overall working process of a fully active deformable intestinal robot based on a bellows, which is characterized by including the following steps: Overall working principle of the robot: The bellows is in a compressed state and is pushed into the intestine from outside the body. At the first corner, the robot activates the bending motion mode, causing one side of the bellows to elongate and the other side to shorten, resulting in a bending motion, enabling the bellows to bend autonomously and pass through the intestinal corner. As the bellows is continuously pushed into the intestine from outside the body, the robot switches its working mode and moves forward in a caterpillar-like linear motion. When the robot reaches the bent part of the bellows, it then switches back to the compression working mode, compressing the stretched side of the bellows that has bent after the corner to straighten the bent part. After straightening, the robot switches to the stretching working mode to spread the bellows in the straight intestine. Subsequently, the robot moves backward in a caterpillar-like linear motion again to reach the position of the first corner, and continues to switch to the bending working mode to enable the bellows to bend actively and pass through the corner. When the front end of the bellows reaches the second corner, the robot uses a caterpillar-like linear motion to reach the front end of the bellows, and then switches to the compression working mode to compress the bellows that was originally in a stretched state. Subsequently, it returns to the first corner to perform a bending motion on the bellows. In this working sequence, the robot moves back and forth continuously until the bellows in the straight channel after the corner can reach the second corner in a compressed state. The corners of the subsequent intestine are still passed through using the above working principle. Based on this principle, the bellows can achieve active deformation throughout the whole process, effectively reducing the harm to the intestine.

[0010] Compared with the prior art, the present invention adopts the above technical solutions and has the following effects: 1. Through the alternating drive of the piezoelectric trolley, the stretching, compression, and active bending of the bellows can be realized, which can adapt to the shape of the intestine and deform actively, reducing the pain of the patient and the damage to the intestine. 2. The piezoelectric drive mechanism has a simple and compact structure and is easy to be designed in a miniaturized way. Description of the Drawings

[0011] Figure 1 Schematic structural diagram of an intestine robot with active deformation throughout the whole process based on a bellows provided by an embodiment of the present invention Figure 2 Exploded view of the structures of the first trolley and the second trolley provided by an embodiment of the present invention; Figure 3 Schematic structural diagram of the piezoelectric vibrator provided by an embodiment of the present invention; Figure 4 Schematic structural diagram of the crawling mechanism provided by an embodiment of the present invention; Figure 5 Exploded view of the structure of the trolley connection part provided by an embodiment of the present invention; Figure 6 Schematic diagram of the applied electrical signal for exciting the longitudinal vibration mode of the piezoelectric vibrator provided by an embodiment of the present invention. The arrow in the figure indicates the polarization direction of the stator; Figure 7 Schematic diagram of the piezoelectric drive for stretching and compressing the bellows provided by an embodiment of the present invention; Figure 8 Schematic diagram of the applied electrical signal for exciting the longitudinal-bending coupling working mode of the piezoelectric vibrator provided by the embodiment of the present invention; the arrow in the figure indicates the polarization direction of the stator; Figure 9 Schematic diagram of the third-order bending vibration and first-order longitudinal vibration modes and elliptical trajectories provided by the embodiment of the present invention; Figure 10 Schematic diagram of the bending of the piezoelectric-driven bellows provided by the embodiment of the present invention; Figure 11 Schematic diagram of the applied electrical signal for exciting the bending-bending coupling working mode of the piezoelectric vibrator provided by the embodiment of the present invention; the arrow in the figure indicates the polarization direction of the stator; Figure 12 Schematic diagram of the first-order bending vibration modes and elliptical trajectories in two orthogonal directions provided by the embodiment of the present invention; Figure 13 Schematic diagram of the inchworm-like linear motion realized by the first to second carts (1-2) and the cart connection part (3) provided by the embodiment of the present invention; Figure 14 Schematic diagram of the process of the bellows realizing active bending provided by the embodiment of the present invention

[0012] In the figure, 1 - the first cart, 2 - the second cart, 3 - the cart connection part, 4 - the bending part, 1.1 - the first crawling mechanism, 1.2 - the second crawling mechanism, 1.3 - the first piezoelectric vibrator, 1.4 - the first screw, 2.1 - the second screw, 2.2 - the second piezoelectric vibrator, 2.3 - the third crawling mechanism, 2.4 - the fourth crawling mechanism, 1.1.1 - the roller shaft, 1.1.2 - the roller, 1.1.3 - the tension spring, 3.1 - the first connecting rod, 3.2 - the second connecting rod, 3.3 - the third connecting rod, 3.4 - the fourth connecting rod, 3.5 - the rivet, 3.6 - the connecting ring, 1.3.1 - the first piezoelectric ceramic, 1.3.2 - the second piezoelectric ceramic, 1.3.3 - the third piezoelectric ceramic, 1.3.4 - the fourth piezoelectric ceramic, 1.3.5 - the first stator. Detailed implementation manners

[0013] The technical solutions of the present invention will be further described in detail below with reference to the accompanying drawings: As Figure 1 shown, the present invention discloses a full-course actively deformable intestinal robot based on a bellows, including the first to second carts (1-2), a cart connection part (3), and a bending part (4); The bending part (4) includes a bellows; As Figure 2 shown, the first cart (1) includes a first piezoelectric vibrator (1.3), a first screw (1.4), and the first to second crawling mechanisms (1.1-1.2); As Figure 3As shown, the first piezoelectric vibrator (1.3) includes a first stator (1.3.5) and first to fourth piezoelectric ceramics (1.3.1 - 1.3.4). The first stator (1.3.5) is a cylindrical thin - wall structure, and four centrally - symmetric grooves are evenly arranged circumferentially in the middle of the outer surface of the first stator (1.3.5). The first to fourth piezoelectric ceramics (1.3.1 - 1.3.4) are bonded in the grooves in the middle of the first stator (1.3.5), and the polarization directions of the first to fourth piezoelectric ceramics (1.3.1 - 1.3.4) all point to the first stator (1.3.5) along the ceramic thickness direction. Four centrally - symmetric grooves are evenly arranged circumferentially at both ends of the first stator (1.3.5). Threads are provided on the inner wall of the first stator for threaded connection with the first screw rod (1.4). The first screw rod (1.4) is a cylindrical threaded rod. Two bosses are provided at one end of the first screw rod (1.4), and through - holes are provided on the sides of the bosses far from the screw center for connection with the connection part (3) of the trolley. The first screw rod (1.4) is hollow for passing medical devices. With the axial direction of the first stator as the reference, the direction from the outside of the first stator to the center is defined as the positive direction of the x - axis, and the direction perpendicular to the x - axis and upward is defined as the positive direction of the y - axis. As Figure 4 As shown, the first crawling mechanism (1.1) includes a roller group and a tension spring (1.1.3). The roller group includes rollers (1.1.2) and roller shafts (1.1.1). The middle structure of the roller (1.1.2) is a cylinder, and the two - end structures are frustum - of - cones, and there is a through - hole at the center of the roller (1.1.2). The roller shaft (1.1.1) is a cylinder, and the two - ends are hemispheres, and holes are drilled at the centers of the hemispheres on both sides. The roller shaft (1.1.1) is placed at the center through - hole of the roller (1.1.2). The center of the tension spring (1.1.3) is a spring, and the two - ends are connection hooks. The connection hooks on both sides of the tension spring (1.1.3) are connected to the holes on both sides of the roller shaft (1.1.1). Each crawling mechanism (1.1) is composed of four roller groups and four tension springs (1.1.3). The tension of the tension spring (1.1.3) exerts a pre - pressure on the four roller groups in the direction towards the center of the first stator (1.3.5), so that the rollers (1.1.2) are in contact with the grooves at both ends of the first stator (1.3.5). As Figure 5As shown, the trolley connection part (3) includes the first to fourth connecting rods (3.1 - 3.4), rivets (3.5), and a connection ring (3.6); the first to fourth connecting rods (3.1 - 3.4) are plate-shaped cuboids with semi-circular plates at both ends, and holes are drilled at the centers of the semi-circular plates at both ends; the connection ring (3.6) is a circular ring structure, and four through-holes symmetrically distributed along the center are evenly arranged on the outer ring of the circular ring; one end of the first to fourth connecting rods (3.1 - 3.4) is hinged to the through-holes of the connection ring (3.6) through rivets (3.5), and the other end is hinged to the through-holes on the convex platform of the screw through rivets (3.5); in this way, the first to second trolleys are connected together; The structure of the second trolley (2) is the same as that of the first trolley (2); the thread rotation directions of the first screw (1.4) and the second screw (2.1), and the first stator (1.3) and the second stator (2.2) are opposite; The trolley connection part (3) can achieve bending with two degrees of freedom, and the trolley connection part (3) can transfer bending moment. When the piezoelectric drive part bends, the torque can still be transmitted to another screw to make it rotate around the x-axis; Blades are provided at both ends of the roller (1.1.2), and the blades are placed in the gaps between the bellows nodes, in this way, the first to second trolleys (1 - 2), the trolley connection part (3), and the bending part (4) are connected; The first to second stators and the first to second screws are made of metal materials; the bellows is made of a flexible material;

[0014] The present invention also discloses a piezoelectric drive implementation method for stretching and compressing a fully active deformable intestinal robot based on a bellows, which is characterized by including the following steps: Stretching and shrinking movement of the bellows: Taking the first trolley as an example, as Figure 6As shown in the figure, a sawtooth wave voltage is used to excite the first to fourth piezoelectric ceramics (1.3.1 - 1.3.4); the two-phase electrical signals have the same phase, exciting the first-order longitudinal vibration mode of the first stator (1.3.5), and the first stator (1.3.5) is in the first-order longitudinal vibration working mode with different reciprocating speeds; due to the different reciprocating vibration speeds, the rollers pressed against both ends of the first stator (1.3.5) by the tension springs are affected by frictional forces with different frictional factors. The hypotenuse of the sawtooth wave corresponds to static friction, and the straight side of the sawtooth wave corresponds to dynamic friction, converting between static friction and dynamic friction, causing the two rollers (1.1.2) on the same side to rotate in opposite directions, and the rollers (1.1.2) on opposite sides to rotate in opposite directions; if the corrugated pipe is to be stretched, only a sawtooth wave electrical signal with a straight side first and then a hypotenuse needs to be applied, then the roller (1.1.2) is first affected by dynamic friction and then by static friction, enabling the roller (1.1.2) to rotate towards both ends of the first stator (1.3.5), and the blades at the gaps between the nodes drive the corrugated pipe to perform a stretching motion; if the corrugated pipe is to be compressed, only a sawtooth wave electrical signal with a hypotenuse first and then a straight side needs to be applied, enabling the roller (1.1.2) to rotate towards the center of the first stator (1.3.5), and the blades drive the corrugated pipe to perform a compression motion, as Figure 7 shown; the principle of the second trolley (2) driving the stretching and contraction of the corrugated pipe is the same as that of the first trolley;

[0015] The present invention also discloses a piezoelectric drive implementation method for the bending of a fully active deformable intestinal robot based on a corrugated pipe, which is characterized by including the following steps: Piezoelectric drive implementation method for the bending of the corrugated pipe along the z-axis: Taking the first trolley as an example, as Figure 8 shown, a sinusoidal alternating current electrical signal is used to excite the first piezoelectric ceramic (1.3.1) and the third piezoelectric ceramic (1.3.3), and a cosine alternating current is used to excite the second piezoelectric ceramic (1.3.2) and the fourth piezoelectric ceramic (1.3.4); the phase difference between the two-phase electrical signals is π / 2, exciting the first-order longitudinal vibration and the third-order bending vibration along the z-axis direction; the third-order bending vibration mode of the piezoelectric vibrator and the first-order longitudinal vibration mode are coupled, generating a small-amplitude elliptical motion of the surface particles in contact with the roller (1.1.2), as Figure 9 shown, the roller (1.1.2) is rotated by frictional drive, and the rollers (1.1.2) on the same side of the first stator (1.3.5) rotate in opposite directions, and the rollers (1.1.2) on opposite sides of the first stator (1.3.5) rotate in the same direction, causing the corrugated pipe on one side of the first stator (1.3.5) to contract and the corrugated pipe on the other side to stretch, thereby forming a bending motion along the z-axis direction, as Figure 10As shown in the figure; to make the corrugated pipe bend in the reverse direction, the first piezoelectric ceramic (1.3.1) and the third piezoelectric ceramic (1.3.3) are excited by a cosine alternating current, and the second piezoelectric ceramic (1.3.2) and the fourth piezoelectric ceramic (1.3.4) are excited by a sine alternating current so that the rotation direction of the roller (1.1.2) is opposite to the original direction; Piezoelectric drive realizes the bending motion of the corrugated pipe along the y-axis: To make the corrugated pipe bend along the y-axis direction, only the third-order bending vibration mode and the first-order longitudinal vibration mode that bend along the y-axis direction need to be excited. The third-order bending vibration mode and the first-order longitudinal vibration mode are coupled to form an elliptical motion to drive the roller (1.1.2) to rotate, thus realizing the bending motion along the y-axis direction;

[0016] The present invention also discloses a piezoelectric drive implementation method for the inchworm-like linear motion of a full-course actively deformable intestinal robot based on a corrugated pipe, which is characterized by including the following steps: The first to second trolleys (1-2) and the trolley connection part (3) realize the inchworm-like linear motion: As Figure 11 shown, the first piezoelectric ceramic (1.3.1) and the third piezoelectric ceramic (1.3.3) are excited by a sine alternating current signal, and the second piezoelectric ceramic (1.3.2) and the fourth piezoelectric ceramic (1.3.4) are excited by a cosine alternating current; the phase difference between the two-phase electric signals is π / 2, and the first-order bending vibration that bends along the y-axis direction and the first-order bending vibration that bends along the z-axis direction of the piezoelectric vibrator are excited. The first-order bending vibration modes in two orthogonal directions are coupled to form an elliptical motion. As Figure 12 shown, in this way, the first screw (1.4) can be driven to generate rotation and linear motion; by changing the order of the voltages applied to the four piezoelectric ceramic pieces, the first screw (1.4) can perform reverse rotation and reverse linear motion; when the first piezoelectric vibrator (1.3) vibrates, the first screw (1.4) is driven to rotate. Since the second piezoelectric vibrator (2.2) does not vibrate, the roller (1.1.2) thereon is in a self-locking state and will not roll. Due to the small friction of the roller (1.1.2) on the first piezoelectric vibrator (1.3), it can move along the corrugated pipe. The rotation of the first screw (1.4) drives the second screw (2.1) to rotate, so that the second screw (2.1) screws out from the second piezoelectric vibrator (2.2), and the first screw (1.4) pushes the vibrating first piezoelectric vibrator (1.3) to perform linear motion; then the first piezoelectric vibrator (1.3) stops vibrating, and the second piezoelectric vibrator (2.2) vibrates. The second screw (2.1) drives the first screw (1.4) to rotate so that the first screw (1.4) screws into the first piezoelectric vibrator (1.3), and the second screw (2.1) pulls the second piezoelectric vibrator (2.2) to perform linear motion; by alternately applying electric signals to the two piezoelectric vibrators, the first to second trolleys (1-2) and the trolley connection part (3) can perform inchworm motion along the corrugated pipe, as Figure 13 shown;

[0017] The present invention also discloses the overall working process of a whole-course actively deformable intestinal robot based on a corrugated pipe, which is characterized by including the following steps: Overall working principle of the robot: As Figure 14 shown, the corrugated pipe is in a compressed state and is pushed into the intestine from outside the body. At the first corner, the robot activates the bending action mode to make one side of the corrugated pipe elongate and the other side shorten to generate a bending motion, enabling the corrugated pipe to bend autonomously and pass through the intestinal corner; as the corrugated pipe is continuously pushed into the body from outside, the robot switches the working mode and performs a caterpillar-like linear motion to move forward. When the robot reaches the bent part of the corrugated pipe, it then switches to the compression working mode to compress the stretched side of the corrugated pipe that has been bent after the corner, making the bent part straight; after straightening, the robot switches to the stretching working mode to spread the corrugated pipe in the straight intestine; then the robot performs a caterpillar-like linear motion backward to continue reaching the first corner position, and continues to switch to the bending working mode to enable the corrugated pipe to actively bend and pass through the corner; when the front end of the corrugated pipe reaches the second corner, the robot uses a caterpillar-like linear motion to reach the front end of the corrugated pipe, and then switches to the compression working mode to compress the corrugated pipe in the original stretched state, and then continues to return to the first corner to perform a bending motion on the corrugated pipe; in this working sequence, the robot moves back and forth continuously until the corrugated pipe in the straight channel after the corner can reach the second corner in a compressed state; the corners of the subsequent intestine still adopt the above working principle to pass through. Based on this principle, the whole-course active deformation of the corrugated pipe can be realized, effectively reducing the harm to the intestine.

Claims

1. An active deformation intestinal robot with full - process initiative based on corrugated pipe and its driving method, characterized in that, It includes the first to second carriages (1-2), a carriage connection part (3), and a bending part (4); The bending part includes a corrugated pipe; The first carriage (1) includes a first piezoelectric vibrator (1.3), a first screw (1.4), and first to second crawling mechanisms (1.1-1.2); the first piezoelectric vibrator (1.3) includes a first stator (1.3.5) and first to fourth piezoelectric ceramics (1.3.1-1.3.4). The first stator (1.3.5) is a cylindrical thin-wall structure, and four circumferentially symmetric grooves are evenly arranged along the middle of the outer surface of the first stator (1.3.5); the first to fourth piezoelectric ceramics (1.3.1-1.3.4) are bonded in the grooves in the middle of the first stator (1.3.5), and the polarization directions of the first to fourth piezoelectric ceramics (1.3.1-1.3.4) all point to the first stator (1.3.5) along the ceramic thickness direction; four circumferentially symmetric grooves are evenly arranged at both ends of the first stator (1.3.5) along the circumference; internal threads are provided on the inner wall of the first stator for threaded connection with the first screw (1.4); the first screw is a cylindrical threaded rod; one end of the first screw (1.4) is provided with two bosses, and through holes are provided on the sides of the bosses away from the screw center for connection with the carriage connection part (3); the first screw (1.4) is hollow for passing medical devices; with the axial direction of the first stator as the reference, the direction from the outside of the first stator to the center is defined as the positive direction of the x-axis, and the direction perpendicular to the x-axis and upward is defined as the positive direction of the y-axis; The first crawling mechanism (1.1) includes a roller group and a tension spring (1.1.3); the roller group includes rollers (1.1.2) and roller shafts (1.1.1); the middle structure of the roller (1.1.2) is a cylinder, and the two ends are frustum cones, and the center of the roller (1.1.2) is a through hole; the roller shaft (1.1.1) is a cylinder, and the two ends are hemispheres, and holes are drilled at the centers of the hemispheres on both sides. The roller shaft (1.1.1) is placed at the center through hole of the roller (1.1.2); the center of the tension spring (1.1.3) is a spring, and the two ends are connection hooks; the connection hooks on both sides of the tension spring (1.1.3) are connected to the holes on both sides of the roller shaft (1.1.1); each crawling mechanism (1.1) is composed of four roller groups and four tension springs (1.1.3). The tension of the tension spring (1.1.3) applies a pre-pressure to the four roller groups in the direction towards the center of the first stator (1.3.5), so that the rollers (1.1.2) contact the grooves at both ends of the first stator (1.3.5); The trolley connection part (3) includes the first to fourth connecting rods (3.1 - 3.4), rivets (3.5), and a connection ring (3.6); the first to fourth connecting rods (3.1 - 3.4) are plate-shaped cuboids with semi-circular plates at both ends, and holes are drilled at the centers of the semi-circular plates at both ends; the connection ring (3.6) is a circular ring structure, and four through-holes symmetrically distributed along the center are evenly arranged on the outer ring of the circular ring; one end of the first to fourth connecting rods (3.1 - 3.4) is hinged to the through-holes of the connection ring (3.6) through rivets (3.5), and the other end is hinged to the through-holes on the convex platform of the screw through rivets (3.5); in this way, the first to second trolleys are connected together; The structure of the second trolley (2) is the same as that of the first trolley (2); the thread directions of the first screw (1.4) and the second screw (2.1), and the first stator (1.3) and the second stator (2.2) are opposite; The trolley connection part (3) can achieve bending with two degrees of freedom, and the trolley connection part (3) can transfer bending moment. When the first to second trolleys (1 - 2) bend, the torque can still be transmitted to the other screw to make it rotate around the x-axis; Blades are provided at both ends of the roller (1.1.2), and the blades are placed in the gaps between the bellows nodes, and in this way, the first to second trolleys (1 - 2), the trolley connection part (3), and the bending part (4) are connected; The first to second stators and the first to second screws are made of metal materials; the bellows is made of a flexible material.

2. The piezoelectric drive implementation method for stretching and compression of a fully active deformable intestinal robot based on a corrugated tube according to any one of claims 1, characterized in that It includes the following steps: Tensile and contraction movements of the bellows: Taking the first trolley as an example, the first to fourth piezoelectric ceramics (1.3.1 - 1.3.4) are excited by a sawtooth wave voltage; the two-phase electrical signals have the same phase, and the first-order longitudinal vibration mode of the first stator (1.3.5) is excited, and the first stator (1.3.5) is in the first-order longitudinal vibration working mode with different reciprocating speeds; due to the different reciprocating vibration speeds, the rollers pressed on both ends of the first stator (1.3.5) by the tension springs are affected by frictional forces with different frictional factors. The hypotenuse of the sawtooth wave corresponds to static friction, and the straight side of the sawtooth wave corresponds to dynamic friction, and it converts between static friction and dynamic friction, so that the rotation directions of the two rollers (1.1.2) on the same side are opposite, and the rotation directions of the rollers (1.1.2) opposite to each other on both sides are opposite; if you want to make the bellows perform a tensile movement, just apply a sawtooth wave electrical signal with a straight side first and then a hypotenuse, then the rollers (1.1.2) are first affected by dynamic friction and then static friction, so that the rollers (1.1.2) can rotate towards both ends of the first stator (1.3.5), and the blades at the gaps between the nodes drive the bellows to make a tensile movement; if you want to make the bellows perform a compression movement, just apply a sawtooth wave electrical signal with a hypotenuse first and then a straight side, so that the rollers (1.1.2) can rotate towards the center of the first stator (1.3.5), and the blades drive the bellows to make a compression movement; the principle of the second trolley (2) driving the tensile and contraction movements of the bellows is the same as that of the first trolley.

3. A method for realizing the bending piezoelectric drive of a whole-course active deformation intestinal robot based on a corrugated pipe according to any one of claims 1, characterized in that It includes the following steps: Method for realizing piezoelectric drive of corrugated pipe bending motion along z-axis: Taking the first trolley as an example, a sinusoidal alternating current signal is used to excite the first piezoelectric ceramic (1.3.1) and the third piezoelectric ceramic (1.3.3), and a cosine alternating current is used to excite the second piezoelectric ceramic (1.3.2) and the fourth piezoelectric ceramic (1.3.4); the phase difference between the two-phase electric signals is π / 2, and a first-order longitudinal vibration and a third-order bending vibration along the z-axis direction are excited; the third-order bending vibration mode and the first-order longitudinal vibration mode of the piezoelectric vibrator are coupled, and a small-amplitude elliptical motion is generated in the surface particles in contact with the roller (1.1.2). Through frictional drive, the roller (1.1.2) rotates, and the rollers (1.1.2) on the same side of the first stator (1.3.5) rotate in opposite directions, and the rollers (1.1.2) opposite to each other on both sides of the first stator (1.3.5) rotate in the same direction, so that the corrugated pipe on one side of the first stator (1.3.5) contracts and the corrugated pipe on the other side stretches, thereby forming a bending motion along the z-axis direction; if the corrugated pipe is to be bent in the reverse direction, the first piezoelectric ceramic (1.3.1) and the third piezoelectric ceramic (1.3.3) are excited by a cosine alternating current, and the second piezoelectric ceramic (1.3.2) and the fourth piezoelectric ceramic (1.3.4) are excited by a sinusoidal alternating current, so that the rotation direction of the roller (1.1.2) is opposite to the original direction. Method for realizing piezoelectric drive of corrugated pipe bending motion along y-axis: A sinusoidal alternating current signal is used to excite the first piezoelectric ceramic (1.3.1) and the third piezoelectric ceramic (1.3.3), and a cosine alternating current is used to excite the second piezoelectric ceramic (1.3.2) and the fourth piezoelectric ceramic (1.3.4); the phase difference between the two-phase electric signals is π / 2, and a third-order bending vibration mode and a first-order longitudinal vibration mode along the y-axis direction are excited. The coupling of the third-order bending vibration mode and the first-order longitudinal vibration mode forms an elliptical motion to drive the roller (1.1.2) to rotate, and thus the bending motion along the y-axis direction can be realized.

4. A piezoelectric drive implementation method for the inchworm-like linear motion of a fully active deformable intestinal robot based on a corrugated tube according to any one of claims 1, characterized in that The method includes the following steps: The first to second trolleys (1-2) and the trolley connection part (3) achieve inchworm-like linear motion: The first piezoelectric ceramic (1.3.1) and the third piezoelectric ceramic (1.3.3) are excited by a sinusoidal alternating current signal, and the second piezoelectric ceramic (1.3.2) and the fourth piezoelectric ceramic (1.3.4) are excited by a cosine alternating current; the phase difference between the two-phase electric signals is π / 2, exciting the first-order bending vibration of the piezoelectric vibrator bending along the y-axis direction and the first-order bending vibration of the piezoelectric vibrator bending along the z-axis direction. The first-order bending vibration modes in two orthogonal directions are coupled to form an elliptical motion, driving the first screw rod (1.4) to generate rotation and linear motion; by changing the order of the voltages applied to the four piezoelectric ceramic pieces, the first screw rod (1.4) can perform reverse rotation and reverse linear motion; when the first piezoelectric vibrator (1.3) vibrates, driving the first screw rod (1.4) to rotate, since the second piezoelectric vibrator (2.2) does not vibrate, the roller (1.1.2) thereon is in a self-locking state and will not roll. Due to the small friction of the roller (1.1.2) on the first piezoelectric vibrator (1.3), it can move along the corrugated pipe. The rotation of the first screw rod (1.4) drives the second screw rod (2.1) to rotate, causing the second screw rod (2.1) to screw out from the second piezoelectric vibrator (2.2), and the first screw rod (1.4) pushes the vibrating first piezoelectric vibrator (1.3) to perform linear motion; subsequently, the first piezoelectric vibrator (1.3) is made not to vibrate, and the second piezoelectric vibrator (2.2) vibrates. The second screw rod (2.1) drives the first screw rod (1.4) to rotate, causing the first screw rod (1.4) to screw into the first piezoelectric vibrator (1.3), and the second screw rod (2.1) pulls the second piezoelectric vibrator (2.2) to perform linear motion; by alternately applying electric signals to the two piezoelectric vibrators, the first to second trolleys (1-2) and the trolley connection part (3) can perform inchworm motion along the corrugated pipe.

5. The overall working process of an active deformation intestinal robot based on corrugated pipes according to any one of claims 1, characterized in that Including the following steps: Overall working principle of the robot: The corrugated pipe is in a compressed state and is pushed into the intestine from outside the body. At the first corner, the robot starts the bending action mode to make one side of the corrugated pipe elongate and the other side shorten to generate a bending motion, enabling the corrugated pipe to achieve autonomous bending and pass through the intestinal corner; As the corrugated pipe is continuously pushed into from outside the body, the robot switches the working mode and performs inchworm-like linear motion to move forward. When the robot reaches the bent part of the corrugated pipe, it then switches back to the compression working mode to compress the stretched side of the corrugated pipe that has been bent after the corner, making the bent part straight; After being straightened, the robot switches to the stretching working mode to spread the bellows in the straight intestine; then the robot moves backward in a caterpillar-like straight-line motion to continue reaching the first corner position, and then switches to the bending working mode to actively bend the bellows to pass through the corner; when the front end of the bellows reaches the second corner, the robot uses the caterpillar-like straight-line motion to reach the front end of the bellows, and then switches to the compression working mode to compress the bellows in the original stretched state, and then continues to return to the first corner to perform a bending motion on the bellows; in this working sequence, the robot continuously reciprocates until the bellows can be in a compressed state in the straight channel after the corner to the second corner; the corners of the subsequent intestine are still passed through using the above working principle, and in this way, the bellows can be actively deformed throughout the process, effectively reducing the damage to the intestine.

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