A magnetic drive micro-sized bistable origami robot, manufacturing method and driving method thereof

Abstract

The application discloses a magnetic drive micro-sized bistable origami robot, a manufacturing method and a driving method thereof. The origami robot comprises a forelimb unit, a body unit and a hindlimb unit which are sequentially connected by hinges, and each of the forelimb unit, the body unit and the hindlimb unit is provided with a flexible hinge to be able to be unfolded or folded; wherein the body unit is provided with a magnet assembly on the surface, the magnet assembly comprises an inclined magnet close to the forelimb unit and a vertical magnet close to the hindlimb unit, and under the excitation of a changing magnetic field, the magnet assembly can drive the origami robot to realize the conversion of different forms; the manufacturing method has the advantages of low cost and high efficiency by using the 3D printing technology, and has good practicability; the driving method allows the robot to switch between the unfolded and folded states, greatly improves the environmental adaptability, wherein the second driving method for realizing the movement of the origami robot enables the origami robot to have two stable movement modes to adapt to complex working environments and task requirements.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of micro robots, and particularly relates to a magnetic drive micro dual-stable origami robot, a manufacturing method and a driving method thereof. BACKGROUND

[0002] The magnetic drive micro robot realizes movement by using a magnetic field, has the advantages of non-contact driving, low energy consumption and high reliability, and can freely move in a complex environment due to its small size and light weight, thereby widening its application scenarios, and is particularly suitable for medical treatment, environmental monitoring and precision manufacturing and the like.

[0003] At the current stage, the magnetic drive micro robot faces multiple design and processing challenges. First, the design of the functional structure of the robot needs to find the best balance between carrying strength and flexibility to ensure that the robot can still realize effective movement in a non-structured road environment at a micro scale; second, the processing precision is high, and the material limitations and precision problems of the processing equipment need to be overcome when manufacturing micro structures; in addition, the control method of the driving system needs to further meet the demand for functional diversity to realize more efficient dynamic response and movement precision.

[0004] Therefore, the present application aims to propose a magnetic drive micro dual-stable origami robot, a manufacturing method and a driving method thereof, to explore technical difficulties in its design, processing and driving, to realize a more efficient micro robot system, to meet the growing market demand, and to have very important significance. SUMMARY

[0005] In order to overcome the technical problems of the prior art described above, the purpose of the present application is to provide a magnetic drive micro dual-stable origami robot, a manufacturing method and a driving method thereof.

[0006] In a first aspect, the present application provides a magnetic drive micro dual-stable origami robot, comprising a front limb unit, a body unit and a rear limb unit connected in sequence by hinges, the front limb unit, the body unit and the rear limb unit are all configured with flexible hinges to be able to flatten or fold; wherein the body unit is configured with a magnet assembly on the surface, the magnet assembly comprises an inclined magnet close to the front limb unit and a vertical magnet close to the rear limb unit, under the excitation of a changing magnetic field, the magnet assembly can drive the origami robot to realize the conversion of different forms.

[0007] As a preferred technical scheme, the body unit comprises adjacent first and second thick plates, and a first flexible hinge is arranged between the first and second thick plates to realize unfolding or folding; when the origami robot is unfolded, vertical projections of the first and second thick plates in a forward direction are the same hexagon; the forelimb unit comprises adjacent third and fourth thick plates, and a second flexible hinge is arranged between the third and fourth thick plates to realize unfolding or folding; when the origami robot is unfolded, vertical projections of the third and fourth thick plates in the forward direction are the same isosceles trapezoid; the hindlimb unit comprises adjacent fifth and sixth thick plates, and a third flexible hinge is arranged between the fifth and sixth thick plates to realize unfolding or folding; when the origami robot is unfolded, vertical projections of the fifth and sixth thick plates in the forward direction are the same isosceles trapezoid.

[0008] As a preferred technical scheme, a fourth flexible hinge is arranged between the first and third thick plates to connect, a fifth flexible hinge is arranged between the second and fourth thick plates to connect, a sixth flexible hinge is arranged between the first and fifth thick plates to connect, and a seventh flexible hinge is arranged between the second and sixth thick plates to connect; when the origami robot is completely folded, the origami robot forms a hexagonal prism.

[0009] As a preferred technical scheme, one side edge of the first thick plate is provided with a first protrusion in the thickness direction, one side edge of the second thick plate is provided with a second protrusion in the thickness direction, and the first flexible hinge is arranged between the first and second protrusions; one side edge of the first thick plate is provided with a third protrusion in the thickness direction, one side edge of the third thick plate is provided with a fourth protrusion in the thickness direction, and the fourth flexible hinge between the first and third thick plates is arranged between the third and fourth protrusions; one side edge of the first thick plate is further provided with a fifth protrusion in the thickness direction, one side edge of the fifth thick plate is provided with a sixth protrusion in the thickness direction, and the sixth flexible hinge between the first and fifth thick plates is arranged between the fifth and sixth protrusions, so that the origami robot has a certain storage space inside when the origami robot is completely folded.

[0010] As a preferred technical scheme, the first, second, third, fourth, fifth and sixth thick plates are all made of polylactic acid material by 3D printing technology.

[0011] As a preferred technical scheme, the first thick plate and the second thick plate are both provided with at least one inclined magnet and at least one vertical magnet, wherein the magnet assemblies are distributed in axial symmetry with respect to the first flexible hinge; the included angles between the vertical magnet, the inclined magnet and the first flexible hinge are 90° and 30° respectively.

[0012] As a preferred technical scheme, the inclined magnet and the vertical magnet are both made of a neodymium iron boron strong magnet made by a zinc-nickel alloy electroplating process.

[0013] In a second aspect, the application further provides a manufacturing method for manufacturing the above-mentioned magnetic driving micro-sized bistable origami robot, comprising the following steps:

[0014] The thick plates and the elastic accommodating grooves are respectively manufactured by 3D printing technology using polylactic acid material and polyurethane material;

[0015] The thick plates are placed into the elastic accommodating grooves, and flexible hinges are arranged at the corresponding connection positions of the thick plates;

[0016] The silica gel film is attached to the surface of each thick plate by polylactic acid;

[0017] The thick plate structure in the folded state is placed into the elastic clamping groove and left for 24 hours;

[0018] The magnet assemblies are pasted on the corresponding surfaces of the first thick plate and the second thick plate according to the design scheme using universal glue, so that the magnetization direction of the magnet assemblies points from the inside of the robot to the edge of the robot.

[0019] In a third aspect, the application further provides a driving method, which comprises a first driving method for realizing different morphological conversion of the origami robot, comprising:

[0020] When the origami robot is placed with one side upward, i.e. in the unfolded state, an electromagnet is arranged below the working plane of the origami robot, and a pulse current is passed through the electromagnet to excite a magnetic field below the origami robot, the magnetic field direction being downward convergence, so that the origami robot obtains a closing torque to switch from the unfolded state to the folded state.

[0021] When the origami robot is in the folded state, a reverse pulse current is passed through the electromagnet to excite a magnetic field below the origami robot, the magnetic field direction being upward divergence, so that the origami robot obtains an unfolding torque to switch from the folded state to the unfolded state.

[0022] As a preferred technical scheme, the driving method further comprises a second driving method for realizing movement of the origami robot, the origami robot comprising two stable movement modes,

[0023] The first steady movement: when the origami robot reciprocatingly deforms in a small range of folding angles, three mutually orthogonal electromagnetic coils are used to excite an alternating reciprocating divergent magnetic field obliquely above the advancing direction of the origami robot, the origami robot is simultaneously subjected to the coupling action of the magnetic torque and the magnetic gradient force, the magnetic torque makes the origami robot reciprocatingly fold and unfold, and the magnetic gradient force makes the pressure applied by the front and rear units on the ground unevenly distributed, so that the robot crawls forward under the driving of the composite magnetic field;

[0024] The second steady movement: when the origami robot is completely folded, the closed magnetic moment is kept, and three mutually orthogonal electromagnetic coils are used to excite a rotating magnetic field in the advancing direction of the origami robot, and the completely folded origami robot rolls forward under the driving of the rotating magnetic field.

[0025] In summary, the present application has the following technical effects:

[0026] The present application is a kind of magnetic drive micro bimodal origami robot, manufacturing method and driving method thereof. The origami robot includes a front unit, a body unit and a rear unit connected in sequence, and the front unit, the body unit and the rear unit are all configured with flexible hinges to be able to flatten or fold. The body unit is provided with a magnet assembly on the surface, which includes an inclined magnet near the front unit and a vertical magnet near the rear unit. Under the excitation of the changing magnetic field, the magnet assembly can drive the origami robot to realize the conversion of different forms. The manufacturing method uses 3D printing technology to print and connect each thick plate, and the silicone film is attached to the surface of each thick plate as a flexible hinge. This manufacturing method has the advantages of high printing precision, overcoming material restrictions, low cost, good practicality and high efficiency. The driving method includes a first driving method for the origami robot to realize the conversion of different forms, and a second driving method for the origami robot to realize movement, allowing the robot to switch between flat and folded states, greatly improving environmental adaptability. The second driving method allows the origami robot to have two stable movement modes: crawling and rolling, to adapt to complex working environments and task requirements. Therefore, compared with existing micro robot technology, the magnetic drive micro bimodal origami robot, manufacturing method and driving method thereof provided by the present application have obvious technical advantages. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the present application or prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0028] Figure 1is a structural schematic view of a flat structure of a paper folding robot according to an embodiment of the present application;

[0029] Figure 2 is a structural schematic view of another angle of a flat structure of a paper folding robot according to an embodiment of the present application;

[0030] Figure 3 is a structural schematic view of a paper folding robot in a small range of folding according to an embodiment of the present application;

[0031] Figure 4 is a structural schematic view of a paper folding robot in a completely folded state according to an embodiment of the present application;

[0032] Figure 5 is a flow schematic view of a manufacturing method of a paper folding robot according to an embodiment of the present application;

[0033] Figure 6 is a process schematic view of a first driving method for a paper folding robot according to an embodiment of the present application;

[0034] Figure 7 is a process schematic view of a second driving method for a paper folding robot according to an embodiment of the present application;

[0035] In the drawings, the reference signs have the following meanings:

[0036] 1 - body unit, 11 - first thick plate, 12 - second thick plate;

[0037] 2 - front arm unit, 21 - third thick plate, 22 - fourth thick plate;

[0038] 3 - rear arm unit, 31 - fifth thick plate, 32 - sixth thick plate;

[0039] 41 - first flexible hinge, 42 - second flexible hinge, 43 - third flexible hinge, 44 - fourth flexible hinge, 45 - fifth flexible hinge, 46 - sixth flexible hinge, 47 - seventh flexible hinge;

[0040] 51 - inclined magnet, 52 - vertical magnet;

[0041] 61 - first protrusion, 62 - second protrusion, 63 - third protrusion, 64 - fourth protrusion, 65 - fifth protrusion, 66 - sixth protrusion. DETAILED DESCRIPTION

[0042] The technical solutions in the embodiments will be described clearly and completely below with reference to the drawings in the embodiments. The embodiments described herein are merely for illustrative purposes, and are not intended to limit the protection scope of the present application, and thus it should be understood that various modifications and changes can be made to the embodiments without departing from the protection scope of the present application.

[0043] In the description of the present application, unless otherwise explicitly specified and limited, the term "and / or" includes any combination and all combinations of one or more associated listed items. Unless otherwise specified or explained, the terms "connection", "fixation" and the like should be understood broadly, for example, "connection" can be fixed connection, or detachable connection, or integral connection, or electrical connection, or signal connection; "connection" can be directly connected, or indirectly connected through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0044] Further, in the description of the present application, it should be understood that the orientation words described in the embodiments are described in the angle shown in the drawings, and should not be understood as a limitation of the embodiments. It should also be understood that, in the context, when referring to one element or feature connected with another element (one or more), it can not only be directly connected with the other element (one or more), but also indirectly connected with the other element (one or more) through an intermediate element.

[0045] Before introducing the technical solutions of the present application, it is necessary to expound the background of the creation of the invention. It is generally known that magnetic-driven micro robots use magnetic fields to achieve movement, with the advantages of non-contact driving, low energy consumption and high reliability. Magnetic-driven micro robots can freely move in complex environments due to their small size and light weight, thereby broadening their application scenarios, especially in medical, environmental monitoring and precision manufacturing fields. Magnetic-driven micro robots have gradually become a research hotspot. Currently, magnetic-driven micro robots face multiple design and processing challenges. First, the design of the robot functional structure needs to find the best balance between carrying strength and flexibility to ensure that the robot can still achieve effective movement in the unstructured road environment under microscale. Second, high processing precision is required, and material limitations and precision problems of processing equipment need to be overcome when manufacturing micro structures. In addition, the control method of the driving system needs to further meet the demand for functional diversity to achieve more efficient dynamic response and motion precision. Therefore, the present application aims to propose a magnetic-driven micro dual-stable origami robot, a manufacturing method and a driving method thereof.

[0046] In a first aspect, please refer to Figures 1 to 4In the exemplary embodiment of the present application, a magnetic drive micro-sized bistable origami robot is provided, which comprises a forelimb unit 32, a body unit 1 and a hindlimb unit connected in sequence, and each of the forelimb unit 32, the body unit 1 and the hindlimb unit is configured with a flexible hinge to be able to be flattened or folded; wherein the body unit 1 is configured with a magnet assembly on the surface, the magnet assembly comprises an inclined magnet 51 close to the forelimb unit 32 and a vertical magnet 52 close to the hindlimb unit, and under the excitation of a changing magnetic field, the magnet assembly can drive the origami robot to realize the conversion of different forms. It should be noted that the origami robot adopts thick plate origami technology, which combines traditional origami and modern engineering, and is a structure using engineering plates as folding panels. Unlike ordinary origami, thick plate origami considers the influence of material thickness on folding form and is applied to the fields of machinery and building.

[0047] The components of the origami robot will be described below:

[0048] Please refer to Figures 1 to 4 , the body unit 1 comprises adjacent first and second thick plates 11 and 12, and a first flexible hinge 41 is arranged between the first and second thick plates 11 and 12 to realize flattening or folding; the forelimb unit 32 comprises adjacent third and fourth thick plates 21 and 22, and a second flexible hinge 42 is arranged between the third and fourth thick plates 21 and 22 to realize flattening or folding; the hindlimb unit comprises adjacent fifth and sixth thick plates 31 and 32, and a third flexible hinge 43 is arranged between the fifth and sixth thick plates 31 and 32 to realize flattening or folding; wherein when the origami robot is flattened, the vertical projection of the first and second thick plates 11 and 12 in the forward direction is the same hexagon, the vertical projection of the third and fourth thick plates 21 and 22 in the forward direction is the same isosceles trapezoid, and the vertical projection of the fifth and sixth thick plates 31 and 32 in the forward direction is the same isosceles trapezoid.

[0049] On the basis of the structure of the above-mentioned forelimb unit 32, body unit 1 and hindlimb unit, in order to realize the flexible connection between the three, please refer to Figures 1 to 4, as a preferred technical solution, the fourth flexible hinge 44 is arranged between the first thick plate 11 and the third thick plate 21 to connect, the fifth flexible hinge 45 is arranged between the second thick plate 12 and the fourth thick plate 22 to connect, the sixth flexible hinge 46 is arranged between the first thick plate 11 and the fifth thick plate 31 to connect, and the seventh flexible hinge 47 is arranged between the second thick plate 12 and the sixth thick plate 32 to connect. Therefore, when the paper folding robot is completely folded, the folding path is that the first thick plate 11 and the second thick plate 12 are folded along the first flexible hinge 41 to realize the folding of the body unit 1, and the third thick plate 21 and the fourth thick plate 22 are folded to the body unit 1 through the second, fourth and fifth flexible hinges to realize the folding of the front limb unit 32, and the folding of the rear limb unit is the same as that of the front limb unit 32, so that the paper folding robot can form a hexagonal prism when it is completely folded, thereby providing a structural basis for the movement mode of the paper folding robot.

[0050] Further, in order to make the paper folding robot have a certain storage space inside when it is completely folded, please refer to Figures 1 to 4 , as a preferred technical solution, the first thick plate 11 is provided with a first protrusion 61 in the thickness direction on one side edge, the second thick plate 12 is provided with a second protrusion 62 in the thickness direction on one side edge, and the first flexible hinge 41 is arranged between the first protrusion 61 and the second protrusion 62; the first thick plate 11 is provided with a third protrusion 63 in the thickness direction on one side edge, the third thick plate 21 is provided with a fourth protrusion 64 in the thickness direction on one side edge, and the fourth flexible hinge between the first thick plate 11 and the third thick plate 21 is arranged between the third protrusion 63 and the fourth protrusion 64; the first thick plate 11 is further provided with a fifth protrusion 65 in the thickness direction on one side edge, the fifth thick plate 31 is provided with a sixth protrusion 66 in the thickness direction on one side edge, and the sixth flexible hinge between the first thick plate 11 and the fifth thick plate 31 is arranged between the fifth protrusion 65 and the sixth protrusion 66. When the paper folding robot is completely folded, the above-mentioned protrusions make the paper folding robot in the shape of a hexagonal prism have a certain thickness, and the inside has a storage space formed by the protrusions, so that the paper folding robot can carry some goods when it is completely folded to carry out clamping and carrying work. For example, in this embodiment, the thickness of each thick plate is 1mm, the thickness of the first protrusion 61 and the second protrusion 62 is 3mm, the thickness of the third protrusion 63, the fourth protrusion 64, the fifth protrusion 65 and the sixth protrusion 66 is 2mm, and the thickness of the paper folding robot when it is completely folded is determined by the first thick plate 11, the second thick plate 12, the first protrusion 61 and the second protrusion 62, that is, a hexagonal prism with a thickness of 8mm is formed. In addition, it should be noted that the first protrusion 61 and the second protrusion 62 correspond to overlap, the third protrusion 63 and the fourth protrusion 64 correspond to overlap, and the fifth protrusion 65 and the sixth protrusion 66 correspond to overlap when the paper folding robot is completely folded.

[0051] As a preferred technical solution, the first thick plate 11, the second thick plate 12, the third thick plate 21, the fourth thick plate 22, the fifth thick plate 31 and the sixth thick plate 32 are all made of polylactic acid material by 3D printing technology. It should be understood that the polylactic acid material has a relatively low melting point, usually between 180-220℃, and is easier to process and print than many other 3D printing materials; in addition, the printing precision of the polylactic acid material is high, and the surface flatness is good, which is suitable for printing detailed articles.

[0052] As a preferred technical solution, the first thick plate 11 and the second thick plate 12 are both provided with at least one inclined magnet 51 and at least one vertical magnet 52, wherein the magnet assembly is axially symmetrically distributed about the first flexible hinge 41; the spatial included angle between the inclined magnet 51, the vertical magnet 52 and the first flexible hinge 41 is 90° and 30°, respectively. As a preferred technical solution, the inclined magnet 51 and the vertical magnet 52 are both made of neodymium-iron-boron strong magnet made by zinc-nickel alloy electroplating process.

[0053] In a second aspect, referring to Figure 5 The application also provides a manufacturing method for manufacturing the above-mentioned magnetically driven micro-sized bistable origami robot, comprising the following steps:

[0054] Step 1: Use polylactic acid material and polyurethane material to make each thick plate and elastic accommodating groove by 3D printing technology;

[0055] Specifically, the polylactic acid wire is heated to 225℃ using a hot melt 3D printer, and after the wire is melted, each thick plate is printed layer by layer through an extruder; then, the thermoplastic polyurethane elastomer wire is melted using a hot melt 3D printer, and the elastic accommodating groove is printed layer by layer through an extruder, and the shape of the elastic accommodating groove is the same as that of the origami robot when it is completely flattened.

[0056] Step 2: Put each thick plate into the elastic accommodating groove, and set a flexible hinge at the corresponding connection of each thick plate;

[0057] Specifically, the printed thick plates are sequentially placed into the elastic accommodating groove, so that the lower surfaces of the thick plates are on the same horizontal plane, wherein the edge profile of the elastic accommodating groove is slightly smaller than the shape of the origami robot when it is completely flattened, ensuring that the elastic accommodating groove and the edges of the thick plates can be completely and tightly fitted, and a flexible hinge is set at the corresponding connection of each thick plate. The flexible hinge is in the form of a thin layer and can be made of rubber materials such as TPU rubber, etc.

[0058] Step 3: Attach a silica gel film to the surface of each thick plate by polylactic acid;

[0059] Specifically, the silicon rubber film is cut into a shape that can be attached to the surface of each thick plate using a cutter, a brush is used to evenly apply an appropriate amount of silicon rubber adhesive near the hinges between adjacent thick plates, then a pair of tweezers is used to attach the cut silicon rubber film to the surface of each thick plate, and in order to ensure that the silicon rubber adhesive is firmly bonded, a force of appropriate size is applied to the film to remove air between the silicon rubber adhesive and the silicon rubber film.

[0060] A hair dryer is used to evenly blow air at a distance of 20 cm from the surface of the silicon rubber film at a temperature of 25°C for about 15 minutes, causing the silicon rubber adhesive to solidify at a relatively fast speed, which can better adhere to the polylactic acid and the silicon rubber film. It should be understood that the polymer colloid generally needs a long time to solidify, and the longer the solidification time, the better the adhesion effect and the better the effect of bearing complex stress.

[0061] Because the colloid has a certain flowability, long-term static solidification can cause the silicon rubber to fill all the gaps between the thick plates. After the colloid is completely solidified, the entire origami robot is cut out of the elastic accommodating groove using a cutter, and then the non-hinge portion of the side of the adjacent thick plate is still cut open using a cutter to remove excess colloid, so as to facilitate folding of the entire origami structure.

[0062] Step 4, place the thick plate structure in the folded state in the elastic clamping groove and stand for 24 hours.

[0063] Long-term folding can form effective prestressed creases in the silicon rubber film at the flexible hinges, making it easier to guide the thick plate origami structure to the target folding path.

[0064] Step 5, use universal glue to paste the magnet assembly on the corresponding surface of the first thick plate and the second thick plate according to the design scheme, so that the magnetization direction of the magnet assembly points from inside the robot to the edge of the robot.

[0065] In a third aspect, the present application also provides a driving method, please refer to Figure 6 , which includes a first driving method for the origami robot to realize different morphological transformations, which includes:

[0066] When the side with the magnet assembly is placed upward, i.e., the origami robot is in a flat state, an electromagnet is arranged below the working plane of the origami robot, a pulse current is passed through the electromagnet to excite a magnetic field with a downward converging direction directly below the origami robot, and the origami robot obtains a closing torque to switch from the flat state to the folded state; when the origami robot is in a folded state, a reverse pulse current is passed through the electromagnet to excite a magnetic field with an upward diverging direction directly below the origami robot, and the origami robot obtains an unfolding torque to switch from the folded state to the flat state.

[0067] The driving method also includes a second driving method for the origami robot to realize movement, please refer to Figure 7The origami robot includes two stable movement modes as follows:

[0068] First stable movement: when the origami robot reciprocally deforms within a small range of folding angles, three mutually orthogonal electromagnetic coils are used to excite an alternating reciprocating divergent magnetic field obliquely above the forward direction of the origami robot, and the origami robot is simultaneously subjected to the coupling of magnetic torque and magnetic gradient force. The magnetic torque makes the origami robot reciprocally fold and unfold, and the magnetic gradient force makes the pressure applied by the front and rear limbs on the ground unevenly distributed, so that the robot crawls forward under the driving of the composite magnetic field. For example, in this embodiment, the basic amplitude of the current is set to 5A, the amplitude coefficient is set to 0.995, 0.0705, 0.0705, the phase is the same, and the frequency is 3Hz, so as to excite an alternating reciprocating divergent magnetic field obliquely above the forward direction of the origami robot. Specifically, when folding, the magnetic gradient force received by the oblique magnet near the front limb is greater than that received by the vertical magnet near the rear limb, so that the front limb is heavier than the rear limb, and thus the friction of the front limb is greater and the friction of the rear limb is smaller. When unfolding, the magnetic gradient force received by the oblique magnet near the front limb is greater than that received by the vertical magnet near the rear limb, so that the front limb is lighter than the rear limb, and thus the friction of the front limb is smaller and the friction of the rear limb is greater. Finally, the origami robot crawls forward under the driving of the composite magnetic field.

[0069] Second stable movement: when the origami robot is completely folded, it assumes an approximate ellipsoidal shape and maintains a closed magnetic moment. Three mutually orthogonal electromagnetic coils are used to excite a rotating magnetic field in the forward direction of the origami robot, and the completely folded origami robot rolls forward under the driving of the rotating magnetic field. For example, in this embodiment, three sinusoidal signals are input to the electromagnetic device, the basic amplitude of the current is set to 5A, the amplitude coefficient is set to 0.4729, 0.9424, 0.9424 respectively, the phase is set to 48.6158°, 277.2°, 180° respectively, and the frequency is 1Hz, so as to excite a rotating magnetic field in the forward direction of the origami robot. The robot has rolling ability in the rotating magnetic field.

[0070] In summary, this driving method includes a first driving method for the origami robot to realize different morphological transformations, and a second driving method for the origami robot to realize movement, allowing the robot to switch between flat and folded states, greatly improving environmental adaptability. The second driving method enables the origami robot to have two stable movement modes: crawling and rolling, to adapt to complex working environments and task requirements.

[0071] It should be pointed out finally that the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit the same; and although the present application has been described in detail with reference to the foregoing embodiments, it should be appreciated by those skilled in the art that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features thereof can be replaced equivalently; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A magnetically driven, miniature, bistable origami robot, characterized in that, The origami robot comprises a forelimb unit, a body unit, and a hindlimb unit connected by sequential hinges. Each of the forelimb unit, body unit, and hindlimb unit is equipped with a flexible hinge to allow it to unfold or fold. The body unit has a magnet assembly on its surface, which includes an oblique magnet near the forelimb unit and a vertical magnet near the hindlimb unit. Under the excitation of a changing magnetic field, the magnet assembly can drive the origami robot to achieve different shape transformations and movements. The body unit includes an adjacent first thick plate and a second thick plate, with a first flexible hinge between them to allow for flattening or folding. When the origami robot is flattened, the vertical projections of the first and second thick plates in the forward direction are identical hexagons. The forelimb unit includes an adjacent third and fourth thick plate, with a second flexible hinge between them to allow for flattening or folding. When the origami robot is flattened, the vertical projections of the third and fourth thick plates in the forward direction are identical isosceles trapezoids. The hindlimb unit includes an adjacent fifth and sixth thick plate, with a third flexible hinge between them to allow for flattening or folding. When the origami robot is flattened, the vertical projections of the fifth and sixth thick plates in the forward direction are identical isosceles trapezoids. A fourth flexible hinge is provided between the first thick plate and the third thick plate for connection; a fifth flexible hinge is provided between the second thick plate and the fourth thick plate for connection; a sixth flexible hinge is provided between the first thick plate and the fifth thick plate for connection; and a seventh flexible hinge is provided between the second thick plate and the sixth thick plate for connection. When the origami robot is fully retracted, the origami robot forms a hexagonal prism. The first thick plate has a first protrusion on one side in the thickness direction, and the second thick plate has a second protrusion on one side in the thickness direction. The first flexible hinge is disposed between the first protrusion and the second protrusion. The first thick plate has a third protrusion on one side in the thickness direction, and the third thick plate has a fourth protrusion on one side in the thickness direction. The fourth flexible hinge between the first thick plate and the third thick plate is disposed between the third protrusion and the fourth protrusion. The first thick plate also has a fifth protrusion on one side in the thickness direction, and the fifth thick plate has a sixth protrusion on one side in the thickness direction. The sixth flexible hinge between the first thick plate and the fifth thick plate is disposed between the fifth protrusion and the sixth protrusion, so that when the origami robot is fully folded up, the origami robot has a certain storage space inside. The first thick plate, the second thick plate, the third thick plate, the fourth thick plate, the fifth thick plate, and the sixth thick plate are all made of polylactic acid material using 3D printing technology; Both the first thick plate and the second thick plate are provided with at least one oblique magnet and at least one vertical magnet, wherein the magnet assembly is axially symmetrical about the first flexible hinge, and the spatial angles between the vertical magnet, the oblique magnet and the first flexible hinge are 90° and 30°, respectively.

2. The origami robot according to claim 1, characterized in that, Both the oblique magnet and the vertical magnet are made of neodymium iron boron strong magnets produced by zinc-nickel alloy electroplating.

3. A method for manufacturing the origami robot according to any one of claims 1-2, characterized in that, include: The thick plates and elastic receiving grooves were fabricated using polylactic acid and polyurethane materials respectively through 3D printing technology. Place each thick plate into the elastic receiving groove, and install flexible hinges at the corresponding connection points of each thick plate; Silicone films are attached to the surfaces of thick plates using polylactic acid; Place each thick plate structure in its folded state into the elastic slot and let it stand for 24 hours; Use all-purpose adhesive to attach the magnet components to the corresponding surfaces of the first and second thick plates according to the design scheme, so that the magnetization direction of the magnet components points from the inside of the robot to the outer edge of the robot.

4. A driving method for the origami robot according to any one of claims 1-2, characterized in that, This includes a first driving method for origami robots to achieve different shape transformations, comprising: When the origami robot is flattened with the side containing the magnet facing up, an electromagnet is placed below the working plane of the origami robot. A pulse current is passed through the electromagnet to generate a magnetic field that converges downwards directly below the origami robot. The origami robot obtains a closing torque and switches from the flattened state to the folded state. When the origami robot is folded up, a reverse pulse current is passed through the electromagnet to generate an upward-diverging magnetic field directly below the origami robot, so that the origami robot obtains an unfolding torque and switches from the folded state to the flattened state.

5. The driving method according to claim 4, characterized in that, The driving method also includes a second driving method for the origami robot to move, and the origami robot includes two steady-state movement modes. First steady-state movement: When the origami robot reciprocates within a small range of folding angles, three orthogonal electromagnetic coils are used to generate an alternating divergent magnetic field diagonally above the direction of the origami robot's movement. The origami robot is simultaneously subjected to the coupling effect of magnetic torque and magnetic gradient force. The magnetic torque causes the origami robot to fold and unfold repeatedly, while the magnetic gradient force causes the pressure applied to the ground by the forelimb and hindlimb units to be unevenly distributed, so that the robot can crawl forward under the drive of the composite magnetic field. Second steady-state movement: When the origami robot is fully folded up, it maintains a closed magnetic moment. Three orthogonal electromagnetic coils are used to generate a rotating magnetic field in the direction of the origami robot's movement. The fully folded origami robot rolls forward under the drive of the rotating magnetic field.

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