Memory alloy driven dionaea muscipula bionic soft manipulator and grabbing method

Abstract

The invention discloses a memory alloy driven dionaea muscipula bionic soft manipulator and a grabbing method. The manipulator comprises a soft driver, a supporting block and a flange plate. The soft driver comprises a soft layer, a memory alloy layer and an insulating heat conduction layer, the soft layer wraps the insulating heat conduction layer, and the insulating heat conduction layer wraps the memory alloy layer; the supporting block is composed of a cross beam and three vertical beams, the cross beam is connected with the soft driver, and the vertical beams are connected with the flange plate; the flange plate comprises an upper layer and a lower layer, the upper layer is connected with the supporting blocks through vertical beams, and the lower layer is connected with an external mechanical arm mechanism. According to the grabbing method, the temperature of the memory alloy is increased through current driving, the memory alloy is induced to be bent and closed, grabbing force adjustment is achieved through temperature regulation and control, and the grabbing task is completed through cooling reset. The problems that a traditional soft manipulator is low in efficiency and complex in control are solved, the soft manipulator has the advantages of being rapid in response and accurate in control, dynamic and irregular objects can be efficiently grabbed, and the soft manipulator is particularly suitable for grabbing tasks in a complex unstructured environment.

Description

Technical Field

[0001] The invention relates to the technical field of soft robots, and in particular to a Venus flytrap bionic soft manipulator driven by a memory alloy and a grasping method. Background Art

[0002] As an intelligent device, manipulators have been widely used in many fields such as automated manufacturing, aerospace, modern medicine, artificial intelligence, microelectronics, and modern logistics. However, traditional rigid manipulators often show shortcomings when handling irregular, fragile, and small objects. Not only is it difficult to achieve stable grasping, but it may also cause damage to the objects. Due to the limitations of structural design and motion characteristics, rigid manipulators can usually only grasp a limited number of objects in specific scenarios and cannot meet the diverse needs of human-computer interaction.

[0003] The Venus flytrap is an excellent insect hunter in nature. It can sense changes in the external environment and respond quickly. It attracts prey by secreting nectar. When the prey touches the inside of the gripper, the Venus flytrap immediately performs a precise capture action. This natural mechanism based on external perception and rapid response provides a new idea for robot grasping technology, especially in the field of efficient grasping in complex service working environments.

[0004] At present, soft manipulators based on memory alloy drive generally adopt traditional gripping methods, but face problems such as low efficiency and complex control. These shortcomings limit the practical application of soft manipulators in multiple fields, and also restrict the performance expansion and technological innovation breakthroughs of soft manipulators under broader scientific and technological needs, which in turn affects the development of soft manipulator technology towards multi-function and intelligent direction. Therefore, it is necessary to design a soft manipulator with enveloping gripping function based on Venus flytrap bionic technology, which has become a key direction to solve these technical problems. Summary of the invention

[0005] In view of the problems existing in the prior art, the present invention provides a memory alloy driven Venus flytrap bionic soft manipulator and a grasping method. This finger cleverly integrates a visual sensor and a temperature sensor, and draws on the exquisite structure of the Venus flytrap to significantly improve the adaptability and grasping ability of the manipulator. This finger can achieve wrapping-type flexible grasping of small and fragile objects and large irregular objects, and uses the friction force of the manipulator and the support force of the fingertips to stably control the objects.

[0006] To achieve the above-mentioned purpose, the present invention provides a memory alloy-driven Venus flytrap bionic soft manipulator, comprising a soft driver, a support block and a flange, wherein the soft driver comprises a soft layer, a memory alloy layer and an insulating heat-conducting layer, wherein the soft layer wraps the insulating heat-conducting layer, and the insulating heat-conducting layer wraps the memory alloy layer; the soft layer, the memory alloy layer and the insulating heat-conducting layer comprise a left region, a middle region and a right region; the left region comprises five fingertip surfaces and a palm surface, the right region comprises four fingertip surfaces and a palm surface, the fingertip surfaces have the same structure and are staggered in position, and the middle region comprises Five connection holes and one assembly hole; the connection holes include a middle hole, a left adjacent hole, a right adjacent hole, a left edge hole and a right edge hole, and the assembly holes and the connection holes are through holes; the left area, the middle area and the right area of ​​the soft layer all have gripping surfaces and envelope surfaces; the envelope surface of the fingertip surface is provided with a power-on hole, the envelope surface of the middle area is provided with two assembly grooves, the palm surface of the soft layer is provided with a heat dissipation hole, and the power-on hole and the heat dissipation hole are through holes, the palm gripping surfaces of the left area and the right area are provided with a herringbone pattern, and the pattern is composed of continuous grooves; the middle area and the fingertip surface of the memory alloy layer are both rectangular; The support block includes a semi-cylindrical cross beam and three identical cylindrical vertical beams; the cross beam includes a curved surface portion and a flat surface portion, and the vertical beams include a left vertical beam, a middle vertical beam, and a right vertical beam; the curved surface portion of the cross beam is connected to one end of the vertical beam by plastic welding, the cross beam is provided with five screw fixing holes and one wiring hole, and the screw fixing holes are connected to the soft drive by screws; the other end surface of the vertical beam is provided with a stud fixing hole, and the stud fixing hole is connected to the flange stud; The flange plate comprises an upper layer and a lower layer, the upper layer is provided with three mounting holes, the mounting holes are connected to the support block studs, and the lower layer is connected to the external mechanical arm mechanism; The axis of the middle hole is the perpendicular bisector of the axis of the beam, and the axes of adjacent connecting holes are equidistant, which is one-fifth of the length of the axis of the beam; the axis of the assembly hole is parallel to the axis of the connecting hole and perpendicular to the axis of the beam, the distance between the axis of the assembly hole and the axis of the middle hole is half the distance between the axis of the assembly hole and the axis of the left hole, and the axis of the wiring hole coincides with the axis of the assembly hole; the assembly groove is arranged at the left and right edges of the envelope surface, fitting the insulating and heat-conducting layer; the axis of the beam is perpendicular to the axes of the three vertical beams, the axis of the left vertical beam coincides with the axis of the left adjacent hole, the axis of the middle vertical beam coincides with the middle hole, and the axis of the right vertical beam coincides with the right adjacent hole; the plane part of the beam coincides with the envelope surface of the middle area of ​​the soft layer; the axis of the stud fixing hole, the axis of the vertical beam, the axis of the screw fixing hole and the axis of the connecting hole are parallel to each other.

[0007] Furthermore, the power-through hole is connected to the positive electrode of the power supply, and the positive electrode of the power supply is connected to the memory alloy through the power-through hole; the power-through holes on the four fingertip surfaces in the right area are connected to the negative electrode of the power supply, and the negative electrode of the power supply is connected to the memory alloy through the power-through holes, and the contact between the memory alloy and the positive electrode and the negative electrode of the power supply is covered with an insulating heat-conductive layer, a visual sensor is installed in the assembly hole, and a temperature sensor is installed in the assembly groove.

[0008] Furthermore, the soft layer is made of silicone soft material, the insulating heat-conducting layer is made of thermally conductive silicone grease material, the memory alloy layer is made of titanium-nickel alloy material, and the screws, studs, support blocks and flanges are made of nylon plastic material.

[0009] On the other hand, the present invention also provides a grasping method of a Venus flytrap bionic soft manipulator driven by a memory alloy, which is characterized by: a grasping method for controlling a soft driver to perform an envelope grasping of a target object, for small and fragile objects, the flexible palm surface of the manipulator can wrap and grasp the target object; and for large and irregular objects, the manipulator can realize envelope grasping of the object by using the interlaced fingertips and the curved palm surface, and the specific process of the grasping method is: S1 Visual Perception: The robot moves to the vicinity of the object under the action of the external robot arm and locates it through the visual sensor so that the soft actuator contacts the surface of the object; S2 Power supply and temperature rise: After receiving the signal from the visual sensor, the DC power supply is used to make the current flow through the memory alloy, and the temperature gradually rises until it reaches a specific range, and the memory alloy begins to bend and close; S3 synergistic drive: The bending and closing effect of the memory alloy drives the insulating heat-conducting layer and the soft layer to bend and close synchronously, making the soft drive enter the bending and closing state; S4 Temperature control and force regulation: Based on the feedback from the temperature sensor, by adjusting the DC power supply current, the temperature of the memory alloy is stabilized in a specific range, so that the manipulator is in a predetermined state and envelope grasping is achieved; S5 Cooling and resetting: After the grasping task is completed, the power supply is stopped. With the synergistic effect of the insulating heat-conducting layer and the heat dissipation holes, the memory alloy is quickly cooled down and restored to the initial open state, completing the grasping process.

[0010] The present invention discloses a bionic Venus flytrap soft manipulator driven by a memory alloy and a grasping method, which have the following beneficial effects: (1) the mechanism gives full play to the memory characteristics of the memory alloy. When the manipulator is blocked by an object, the unblocked area can still be bent and deformed under the action of the memory alloy, thereby ensuring that the manipulator is in full contact with the object and improving its adaptability and grasping ability; (2) the end of the manipulator is provided with fingertips. When the manipulator is difficult to close, the support force provided by the fingertips can achieve the purpose of stable grasping; (3) by drawing on the grasping mechanism of the bionic Venus flytrap and integrating temperature and visual sensors, the manipulator has the ability to sense the type and position of the object, and can adjust the grasping force accordingly, thereby achieving an intelligent and flexible enveloping flexible grasping effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic diagram of the overall structure of a Venus flytrap bionic soft manipulator driven by a memory alloy of the present invention; Figure 2 It is a schematic diagram of the overall structure of a Venus flytrap bionic soft manipulator driven by a memory alloy of the present invention in a bent and closed state; Figure 3 It is a closed and bent top view of a soft driver of a Venus flytrap bionic soft manipulator driven by a memory alloy of the present invention; Figure 4 It is a schematic diagram of a flange of a Venus flytrap bionic soft manipulator driven by a memory alloy of the present invention; Figure 5 It is an exploded view of the middle surface of a soft driver of a Venus flytrap bionic soft manipulator driven by a memory alloy of the present invention; Figure 6 It is a schematic diagram of a support block of a Venus flytrap bionic soft manipulator driven by a memory alloy of the present invention; Figure 7 The present invention is a schematic diagram of the overall structure of a Venus flytrap bionic soft manipulator driven by a memory alloy in an open state.

[0012] in: Figure 1 Middle: 1.Software driver; 2.Support block; 3.Flange; Figure 2 Middle: 101. Fingertip surface; 102. Palm surface; 103. Heat dissipation hole; 4. Power supply hole; Figure 3 Center: 104. Herringbone pattern; 5. Left area; 6. Right area; 7. Middle area; Figure 4 Middle: 301. Upper layer; 302. Mounting hole; 303. Lower layer; Figure 5Middle: 8. Assembly hole; 9. Connection hole; 901. Left edge hole; 902. Left adjacent hole; 903. Middle hole; 904. Right adjacent hole; 905. Right edge hole; 10. Visual sensor; 11. Memory alloy layer; 12. Insulation and heat-conducting layer; 13. Soft layer; 1301. Grasping surface; 1302 Envelope surface; 14. Temperature sensor; 15. Assembly slot; Figure 6 Center: 16. Horizontal beam; 1601. Screw fixing hole; 1602. Wiring hole; 1701. Stud fixing hole; 1702. Left vertical beam; 1703. Middle vertical beam; 1704. Right vertical beam. DETAILED DESCRIPTION

[0013] In order to further understand the memory alloy driven Venus flytrap bionic soft manipulator provided by the present invention, the present invention is specifically described below in conjunction with the accompanying drawings and detailed embodiments, and the content of the present invention is not limited to the embodiments.

[0014] refer to Figures 1 to 7 The present invention provides a memory alloy driven Venus flytrap bionic soft manipulator, comprising a soft driver (1), a support block (2) and a flange (3), wherein the soft driver (1) comprises a soft layer (13), a memory alloy layer (11) and an insulating heat-conducting layer (12), wherein the soft layer (13) wraps the insulating heat-conducting layer (12), and the insulating heat-conducting layer (12) wraps the memory alloy layer (11), thereby achieving a compact structure and efficient driving; The soft layer (13), the memory alloy layer (11) and the insulating heat-conducting layer (12) include a left region (5), a middle region (6) and a right region (7); the left region (5) includes five fingertip surfaces (101) and a palm surface (102); the right region (7) includes four fingertip surfaces (101) and a palm surface (102); the fingertip surfaces (101) have the same structure and are staggered in position; the middle region (6) includes five connecting holes (9) and an assembly hole (8); the connecting hole (9) includes a middle hole (903), a left adjacent hole (902), a right adjacent hole (904), a left edge hole (901) and a right edge hole (905); the assembly hole (8) and the connecting hole (9) are through holes; the left region (5), the middle region (6) and the right region of the soft layer (13) include five fingertip surfaces (101) and a palm surface (102); the fingertip surfaces (101) have the same structure and are staggered in position; the middle region (6) includes five connecting holes (9) and an assembly hole (8); the connecting hole (9) includes a middle hole (903), a left adjacent hole (902), a right adjacent hole (904), a left edge hole (901) and a right edge hole (905); the assembly hole (8) and the connecting hole (9) are through holes; (7) both have a gripping surface (1301) and an envelope surface (1302); the envelope surface (1302) of the fingertip surface (101) is provided with a power-on hole (4), the envelope surface (1302) of the middle region (6) is provided with two assembly grooves (15), a heat dissipation hole (103) is provided on the palm surface (102) of the soft layer (13), the power-on hole (4) and the heat dissipation hole (103) are both through holes, the gripping surface (1301) of the palm surface (102) of the left region (5) and the right region (7) are provided with a herringbone pattern (104), the pattern is composed of continuous grooves; the middle region (6) and the fingertip surface (101) of the memory alloy layer (11) are both rectangular, and the memory alloy layer is a complete piece of memory alloy; the designed herringbone pattern (104) can provide greater friction for the software driver (1) to prevent objects from falling; Furthermore, the support block (2) comprises a semi-cylindrical cross beam (16) and three identical cylindrical vertical beams; the cross beam (16) comprises a curved surface portion and a flat surface portion, and the vertical beams comprise a left vertical beam (1702), a middle vertical beam (1703), and a right vertical beam (1704); the curved surface portion of the cross beam (16) is connected to one end of the vertical beam by plastic welding, the cross beam (16) is provided with five screw fixing holes (1601) and one wiring hole (1602), and the screw fixing hole (1601) is connected to the soft drive (1) by screws; the other end surface of the vertical beam is provided with a stud fixing hole (1701), and the stud fixing hole (1701) is connected to the flange (3) by a stud; Furthermore, the flange (3) comprises an upper layer (301) and a lower layer (303), the upper layer (301) is provided with three mounting holes (302), the mounting holes (302) are connected to the studs of the support block (2), and the lower layer (303) is connected to an external mechanical arm mechanism; Furthermore, the axis of the middle hole (903) is the perpendicular bisector of the axis of the crossbeam (16); the axes of the adjacent connecting holes (9) are equidistant from each other, and the distance is one-fifth of the length of the axis of the crossbeam (16); the axis of the assembly hole (8) is parallel to the axis of the connecting hole (9) and perpendicular to the axis of the crossbeam (16); the distance between the axis of the assembly hole (8) and the axis of the middle hole (903) is half the distance between the axis of the assembly hole (8) and the axis of the left hole; the axis of the wiring hole (1602) coincides with the axis of the assembly hole (8); the assembly groove (15) is provided at the left and right edges of the envelope surface (1302) and fits the insulating heat-conducting layer (12); the axis of the crossbeam (16) is perpendicular to the axes of the three vertical beams; the left vertical beam (1702) is perpendicular to the axes of the three vertical beams. ) axis coincides with the axis of the left adjacent hole (902), the axis of the middle vertical beam (1703) coincides with the middle hole (903), and the axis of the right vertical beam (1704) coincides with the right adjacent hole (904); the plane portion of the cross beam (16) coincides with the envelope surface (1302) of the middle region (6) of the soft layer (13); the axis of the stud fixing hole (1701), the axis of the vertical beam, the axis of the screw fixing hole (1601) and the axis of the connecting hole (9) are parallel to each other.

[0015] Furthermore, the power-through hole (4) is connected to the positive electrode of a power source, and the positive electrode of the power source is connected to the memory alloy layer (11) through the power-through hole (4); the power-through holes (4) on the four fingertip surfaces (101) on the right region (7) are connected to the negative electrode of the power source, and the negative electrode of the power source is connected to the memory alloy layer (11) through the power-through hole (4); the contact between the memory alloy layer (11) and the positive electrode and the negative electrode of the power source is covered with an insulating heat-conducting layer (12); a visual sensor (10) is installed in the assembly hole (8); a temperature sensor (14) is installed in the assembly slot (15); and the soft manipulator integrating the sensors can realize intelligent recognition of the position of an object and intelligent adjustment of the temperature of the memory alloy.

[0016] Furthermore, the soft layer (13) is made of silicone soft material, the insulating heat-conducting layer (12) is made of thermal grease material, the memory alloy layer (11) is made of titanium-nickel alloy material, and the screws, studs, support blocks (2) and flanges (3) are made of nylon plastic material. The manipulator incorporates the titanium-nickel alloy material. By adjusting the nickel content in different regions of the titanium-nickel alloy, the fingertip surface (101) and the palm surface (102) of the memory alloy layer (11) are bent at their junction, while the fingertip surface (101) and the middle region (6) in other regions always maintain an initial planar structure, thereby ensuring that the soft manipulator has an envelope function. Its good shape memory effect can accurately preset the grasping posture and achieve accurate and stable grasping. The thermal grease material wrapped around the memory alloy has good heat dissipation performance. It cooperates with the heat dissipation holes (103) to quickly reduce the temperature of the memory alloy and ensure that the manipulator opens quickly. The insulating nylon plastic material can prevent leakage problems caused by damage to the insulating heat-conducting layer (12), thereby fully ensuring the efficient and safe operation of the manipulator.

[0017] On the other hand, the present invention also provides a method for grasping a Venus flytrap bionic soft manipulator driven by a memory alloy, and the specific method is: First, the robot is positioned through an external robot arm and a visual sensor (10), and the soft driver (1) is moved to the surface of the object; after receiving the signal from the visual sensor (10), the memory alloy is heated by a DC power supply until it bends and closes, driving the soft layer (13) to bend and close synchronously; based on the feedback of the temperature sensor (14), the current is adjusted to stabilize the temperature of the memory alloy, so as to achieve the envelope grasping of the robot soft hand; finally, the power supply is stopped, and the memory alloy is cooled under the action of the insulating heat conductive layer (12) and the heat dissipation hole (103), and restored to the initial open state, completing the grasping process. This grasping method avoids the accurate judgment of the position of the target object, and can achieve the purpose of efficient and easy-to-control grasping.

[0018] The implementation of the above-mentioned memory alloy driven Venus flytrap bionic soft manipulator is not limited to the implementation form described in the above specific implementation mode. According to the content disclosed in the present invention, technicians in the relevant technical field can also adopt other specific methods to modify, replace with equivalents, improve, etc. on the basis of the patent of the present invention. Therefore, the embodiment cannot be understood as the only specific implementation mode that can be implemented in the present invention.

Claims

1. A Venus flytrap bionic soft manipulator driven by memory alloy, characterized by: The invention comprises a soft drive, a support block and a flange, wherein the soft drive comprises a soft layer, a memory alloy layer and an insulating heat-conducting layer, wherein the soft layer wraps the insulating heat-conducting layer, and the insulating heat-conducting layer wraps the memory alloy layer; the soft layer, the memory alloy layer and the insulating heat-conducting layer comprise a left region, a middle region and a right region, wherein the left region and the right region comprise a fingertip surface and a palm surface, and the middle region comprises a connecting hole and an assembly hole; the left region, the middle region and the right region of the soft layer have a gripping surface and an envelope surface, wherein the envelope surface of the fingertip surface is provided with a power-on hole, the envelope surface of the middle region is provided with an assembly groove, and the palm surface of the soft layer is provided with a heat dissipation hole; The support block comprises a horizontal beam and a vertical beam, the horizontal beam is provided with a screw fixing hole and a wiring hole, the screw fixing hole is connected to the soft drive by screws, and the vertical beam is provided with a stud fixing hole, and the stud fixing hole is connected to the flange stud; The flange comprises an upper layer and a lower layer, the upper layer is provided with a mounting hole, the mounting hole is connected to the support block stud, and the lower layer is connected to the external mechanical arm mechanism; The axial distances of adjacent connecting holes are the same, the axial line of the wiring hole coincides with the axial line of the assembly hole, and the assembly grooves are arranged at the left and right edges of the envelope surface to fit the insulating heat-conducting layer.

2. The Venus flytrap bionic soft manipulator driven by a memory alloy according to claim 1, characterized in that: The power-through hole is connected to the positive electrode of the power supply, and the positive electrode of the power supply is connected to the memory alloy layer through the power-through hole; the power-through hole on the fingertip surface in the right area is connected to the negative electrode of the power supply, and the negative electrode of the power supply is connected to the memory alloy layer through the power-through hole, and the contact between the memory alloy layer and the positive electrode and the negative electrode of the power supply is covered with an insulating heat-conductive layer, a visual sensor is installed in the assembly hole, and a temperature sensor is installed in the assembly groove.

3. The Venus flytrap bionic soft manipulator driven by a memory alloy according to claim 1, characterized in that: The soft layer is made of silicone soft material, the insulating heat-conducting layer is made of heat-conducting silicone grease material, the memory alloy layer is made of titanium-nickel alloy material, and the screws, studs, support blocks and flanges are made of nylon plastic material.

4. A grasping method of a Venus flytrap bionic soft manipulator driven by a memory alloy, characterized in that: A method for controlling a software driver to perform an envelope-type grasping of a target object. The specific steps are: S1 Visual Perception: The manipulator moves toward the object under the positioning of the external manipulator and the visual sensor, so that the soft actuator contacts the surface of the target object; S2 Power supply and temperature rise: After receiving the signal from the visual sensor, power is supplied through a DC power supply, so that current flows through the memory alloy, and the temperature rises to the phase transition temperature value at which the memory alloy bends and closes; S3 Collaborative drive: Under the bending and closing action of the memory alloy, the soft actuator performs an enveloping grasping of the target object; S4 stable control: Based on the feedback from the temperature sensor, the temperature of the memory alloy is stabilized at the phase change temperature by adjusting the DC power supply current; S5 Cooling and resetting: After the grasping task is completed, the power supply is stopped. With the synergistic effect of the insulating heat-conducting layer and the heat dissipation holes, the memory alloy is quickly cooled down and restored to the initial open state.

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