A tensegrity-structured bistable flexible gripper with adjustable gripping performance

Abstract

The present invention relates to a tensegrity bistable flexible gripper with adjustable clamping performance, comprising a base, a driving module, a tensegrity bistable mechanism and a pair of flexible clamping claws; the driving module comprises an electric push rod and two servos, the tensegrity bistable mechanism comprises a trigger rod, a pair of triangular clamping plates, a pair of floating plates and three groups of springs, the components are hinged, the first two groups of springs are respectively connected to the nodes of the components, and the lower end of the third group of springs is connected to the servo by a pull rope passing around the node on the base, and the gripping performance, including the gripping force and anti-collision ability of the gripper, is adjusted by rotating the servo; when the trigger rod moves inward due to external collision and reaches the trigger state, the gripper closes quickly to complete the gripping process; the electric push rod is pushed out to drive the trigger rod forward to complete the gripper opening process, and the trigger rod moves backward to actively close the gripper; the electric push rod is retracted and retracted in the gripper open state to adjust the potential energy barrier and anti-interference ability required for triggering, and to perform selective gripping.

Description

Technical Field

[0001] The present invention belongs to the technical field of robot grippers, and in particular relates to a tensegrity structure bistable flexible gripper with adjustable gripping performance. Background Art

[0002] A bistable structure possesses two stable equilibrium states. When the energy absorbed by the structure reaches a potential energy barrier, it crosses the potential energy peak and rapidly switches to the other stable state, accompanied by energy output. Using a bistable structure can increase the gripping speed of a gripper. Furthermore, a bistable structure maintains its stable state without the need for continuous external energy input, making the bistable gripper self-sustaining. A tensegrity structure generally consists of a compressive rigid unit and a continuous tensioned cable unit. A tensegrity structure is a rigid-flexible coupled structure whose structural stiffness can be modified by varying the stiffness and pre-tension of the tensioned cable units. Furthermore, the tensegrity structure possesses a certain energy-absorbing capacity. Current bistable grippers typically cannot adjust the gripping force or potential energy barrier and only have a single gripping mode. This makes it difficult to grasp objects of varying properties (size, hardness, weight).

[0003] Some researchers have proposed a bistable structure with an adjustable potential energy barrier. One significance of the adjustable potential energy barrier is that it can selectively grasp objects with different kinetic energies. If the input energy is less than the potential energy barrier, the structure cannot be triggered. For example, Chinese patent CN113370239B discloses a bistable passive trigger soft gripper with an adjustable energy barrier, and the paper "Yonakang Jiang, Xin Tong, Jian Li, Chongjing Cao, Xing Gao, Yinatian Li. Reprogrammable Bistable Actuators for Multimodal Fast, and Ultrasensitive Grasping." published in the international journal "IEEE / ASME Transactions on Mechatronics". However, the current adjustable performance of bistable grippers is mainly limited to the potential energy barrier. The adjustment of grasping force, flexible grasping ability, anti-collision ability, anti-interference energy and energy absorption performance is at a low level, making it difficult to cope with objects with different weights, strengths, kinetic energies and other factors, as well as working environments under different interference conditions. Summary of the Invention

[0004] The object of the present invention is to provide a bistable flexible gripper of a tensegrity structure with adjustable clamping performance, the gripper having adjustable tensegrity structural stiffness, clamping force, potential energy barrier, anti-interference ability and anti-collision ability to cope with objects to be grasped under different conditions and working environments with different interference conditions; the gripper can adjust the clamping force according to factors such as the weight, surface roughness, and structural strength of the grasped object, adjust the potential energy barrier according to the kinetic energy of the grasped object to achieve selective grasping of the object, adjust the tensegrity structural stiffness according to different working environments to adjust the anti-interference ability and anti-collision ability of the gripper, and at the same time achieve flexible adaptive grasping of the target object.

[0005] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a tensile integral structure bistable flexible gripper with adjustable clamping performance, comprising a base, a driving module, a tensile bistable mechanism and a pair of flexible clamping claws; the driving module comprises an electric push rod and two servos, the electric push rod is installed in the middle of the base, and the two servos are symmetrically installed on the left and right sides of the base; the tensile bistable mechanism comprises a trigger rod, a pair of triangular splints, a pair of floating plates and three sets of springs; the trigger rod is composed of a straight rod with a trigger surface on the upper part, an intermediate rotating connecting part and a lower strip slide, the upper end of the push rod of the electric push rod is connected to a top block, and the top block is embedded in the strip slide; the pair of triangular splints are symmetrically arranged on the left and right sides of the upper end of the base, and are connected to the rotating connection on the left and right sides of the upper end of the base through the first connecting node at their lower part. The connecting node is rotatably connected; the pair of floating plates are symmetrically arranged, and the two floating plates are rotatably connected to the rotating connection part of the trigger rod through the third connection node on the inner side thereof, and the two floating plates are rotatably connected to the second connection node on the corresponding triangular clamping plate through the fourth connection node on the upper part thereof; the two first springs are arranged front and back, and the left and right ends of the first spring are respectively rotatably connected to the second connection nodes on the two triangular clamping plates; the two second springs are arranged front and back, and the left and right ends of the second spring are respectively rotatably connected to the fifth connection nodes on the two floating plates; a pull rope is connected to each of the two servos, and the pull rope passes around the corresponding first connection node and is connected to one end of the third spring, and the other end of the third spring is rotatably connected to the fifth connection node on the corresponding floating plate; the pair of flexible clamps are symmetrically installed on the two triangular clamping plates.

[0006] Furthermore, the left and right sides of the base are respectively provided with a plurality of servo mounting holes, the lower part of the base is provided with a plurality of push rod mounting holes, and the upper part of the base is provided with a limiting slide groove; the two servos are symmetrically installed on the left and right sides of the base and are fixedly connected to the servo mounting holes on the left and right sides of the base through fasteners; the electric push rod is installed in the middle of the base and the lower part thereof is fixedly connected to the push rod mounting holes at the lower part of the base through fasteners; the push rod mounting holes are also used to install the gripper at the end of a robotic arm or a drone; a slider is provided at the upper end of the push rod of the electric push rod, and a top block is connected to the slider, the slider slides up and down in the limiting slide groove, and the top block slides up and down in the strip slide groove.

[0007] Furthermore, connecting supports are provided on the left and right sides of the upper end of the base, and the connecting supports are rotatably connected to the first connecting node at the lower part of the triangular splint through a parent and child screw, and a narrow slot is opened on the connecting support, one end of which is connected to the pull rope of the servo swing arm, and the other end thereof passes through the narrow slot and bypasses the parent and child screw to be connected to the third spring.

[0008] Furthermore, the triangular splint is a double-layer hollow structure with a right-angled triangle as the main body. The upper end of the triangular splint is a plane and is fixedly connected to the flexible clamp. A second connection node is set on the hypotenuse of the triangular splint. The second connection node is rotatably connected to the fourth connection node of the floating plate and one end of the first spring through a parent and child screw.

[0009] Furthermore, the swimming plate passes through a triangular splint with a double-layer hollow structure, and the fifth connection node of the swimming plate is rotatably connected to the second springs on the front and rear sides and the third spring in the middle through a parent-child screw.

[0010] Furthermore, the trigger surface on the upper portion of the trigger rod has a certain curvature to adapt to the shape of the object being grasped, and a silicone layer is provided on the trigger surface to reduce direct impact on the object being grasped.

[0011] Furthermore, the flexible clamp is used to achieve flexible and adaptive grasping of the grasped object, and the lower end of the flexible clamp is fixedly connected to the upper surface of the triangular clamp by a fastener; the upper part of the flexible clamp adopts a fin-like structure, and a plurality of ribs with gradient angles are arranged inside it, so that the deformation ability of the fin at different distances is adapted to the clamping force of the gripper, and the flexible clamp is provided with a serrated structure on the contact surface with the grasped object to increase friction and load capacity, and the flexible clamp is provided with a buffer boss on the contact part with the trigger rod to buffer the collision between the flexible clamp and the trigger rod when the gripper is closed.

[0012] Furthermore, the flexible clamp is made of TPU material through 3D printing.

[0013] Furthermore, the base, triangular splint, swimming plate, and trigger rod are all made of PLA material through 3D printing.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] 1. The tensegrity-structured bistable flexible gripper provided by the present invention can achieve rapid grasping of target objects by means of energy output during steady-state switching. It can be used for rapid grasping of dynamic targets and does not require continuous energy input to maintain the gripper's open or grasping state.

[0016] 2. Through the adjustment of the electric push rod and the servo, the gripper of the present invention has a variety of adjustable gripping performances to cope with different gripping targets and different gripping environments.

[0017] 1) The gripping force can be adjusted based on factors such as the weight, surface roughness, and structural strength of the object being gripped. The servo rotates the swing arm to reduce the extension of the third spring, thereby increasing the gripping force of the gripper.

[0018] 2) The tensegrity gripper's energy absorption and collision resistance can be adjusted according to different movement speeds. The servo rotates the swing arm, increasing the extension of the third spring and the tensegrity structure's stiffness, which can improve the gripper's energy absorption and collision resistance in collisions.

[0019] 3) The trigger potential energy barrier can be adjusted according to the weight and kinetic energy of the object to achieve selective grasping of an object (if the kinetic energy of the object is less than the potential energy barrier, it cannot be triggered). Retracting the electric push rod can pull the trigger rod to the trigger position, lowering the required potential energy barrier;

[0020] 4) The gripper’s anti-interference capability can be adjusted according to the working environment with different interference intensities. Extending the electric push rod can increase the potential energy barrier and reduce the possibility of the bistable structure being falsely triggered by vibration or other interference;

[0021] 3. The flexible gripper of the present invention can adapt to the shape of the object to be grasped to perform enveloping grasping, thereby improving the grasping success rate and the weight of the graspable target, and plays a buffering role during the grasping process to protect the grasped object;

[0022] 4. The components of the present invention have simple structures, low implementation costs and simple control. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 2 is a schematic diagram of the overall structure of a tensegrity-structured bistable flexible gripper according to an embodiment of the present invention;

[0024] Figure 2 is a schematic structural diagram of a base in an embodiment of the present invention;

[0025] Figure 3 2 is a schematic structural diagram of a triangular splint according to an embodiment of the present invention;

[0026] Figure 4 2 is a schematic structural diagram of a floating plate in an embodiment of the present invention;

[0027] Figure 5 is a schematic structural diagram of a trigger lever in an embodiment of the present invention;

[0028] Figure 6 is a schematic structural diagram of a flexible clamping jaw in an embodiment of the present invention;

[0029] Figure 7 Schematic diagram of the gripper opening and closing (active + passive) process in an embodiment of the present invention;

[0030] Figure 8 Schematic diagram of the process of adjusting the potential energy barrier, overall structural stiffness, clamping force, anti-interference ability and anti-collision ability of the gripper in an embodiment of the present invention;

[0031] Figure 9 is a mathematical simulation curve diagram of the adjustment of the barrier of the grabbing gesture energy according to an embodiment of the present invention;

[0032] Figure 10 It is a mathematical simulation curve diagram of the gripper clamping force adjustment in an embodiment of the present invention.

[0033] In the figure: 1-base; 2-drive module; 3-tensioning bistable mechanism; 4-flexible clamping claw; 5-electric push rod; 6-servo; 7-trigger rod; 8-triangular splint; 9-swimming plate; 10-first spring; 11-second spring; 12-third spring. DETAILED DESCRIPTION

[0034] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0035] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present application belongs.

[0036] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0037] like Figure 1As shown, this embodiment provides a tensile integral structure bistable flexible gripper with adjustable clamping performance, including a base 1, a drive module 2, a tensile bistable mechanism 3 and a pair of flexible clamps 4. The drive module 2 includes an electric push rod 5 and two servos 6. The electric push rod 5 is installed in the middle of the base 1, and the two servos 6 are symmetrically installed on the left and right sides of the base 1. The tensile bistable mechanism 1 includes a trigger rod 7, a pair of triangular splints 8, a pair of floating plates 9 and three sets of springs. The trigger rod 7 is composed of a straight rod with a trigger surface on the upper part, a middle rotating connection part and a lower strip slide. The upper end of the push rod of the electric push rod 5 is connected to a top block, and the top block is embedded in the strip slide. The pair of triangular splints 8 are symmetrically arranged on the left and right sides of the upper end of the base 1, and are rotatably connected to the rotating connection nodes on the left and right sides of the upper end of the base 1 through the first connection node at the lower part. The pair of floating plates 9 are symmetrically arranged, and both floating plates 9 are simultaneously rotatably connected to the rotational connection portion of the trigger lever 7 via their inner third connection nodes. Each floating plate 9 is rotatably connected to the second connection node on the corresponding triangular clamping plate 8 via its upper fourth connection node. Two first springs 10 are arranged front and back, with the left and right ends of each first spring 10 rotatably connected to the second connection nodes on the two triangular clamping plates 8. Two second springs 11 are arranged front and back, with the left and right ends of each second spring 11 rotatably connected to the fifth connection nodes on the two floating plates 9. A pull rope is connected to each of the two servos 6. The rope passes through the corresponding first connection node (i.e., the rotation connection node on the base 1) and is connected to one end of a third spring 12. The other end of the third spring 12 is rotatably connected to the fifth connection node on the corresponding floating plate 9. The pair of flexible jaws 4 are symmetrically mounted on the two triangular clamping plates.

[0038] The base 1 is used to install the driving mold 2, the tensioning bistable mechanism 3 and the gripper at the end of the robot arm or the drone. Figure 2 As shown, four servo mounting holes are respectively provided on the left and right sides of the base 1, four push rod mounting holes are provided on the lower part of the base 1, and a limited slide groove is provided on the upper part of the base 1; two servos 6 are symmetrically installed on the left and right sides of the base 1 and are fixedly connected to the servo 6 mounting holes on the left and right sides of the base 1 through fasteners; the electric push rod 5 is installed in the middle of the base 1 and its lower part is fixedly connected to the push rod mounting hole at the lower part of the base 1 through fasteners; the push rod mounting hole is also used to install the gripper at the end of the robotic arm or drone.

[0039] The upper end of the electric push rod 5 is provided with a slider, to which a top block is connected. The slider slides up and down within the limiting chute, and the top block slides up and down within the strip chute. The drive module 2, consisting of the electric push rod 5 and two servos 6, is used to open and close the gripper. By adjusting the structural stiffness of the gripper's tensegrity structure, the clamping force, potential energy barrier, anti-interference ability, and anti-collision ability are changed. When the electric push rod 5 is pushed out, the top block pushes the trigger rod 7 upward, thereby opening the gripper; when the electric push rod 5 is retracted, the top block pulls the trigger rod 7 downward, actively closing the gripper and adjusting the potential energy barrier.

[0040] Connecting supports are provided on the left and right sides of the upper end of the base 1, and the connecting supports are rotatably connected to the first connecting node at the lower part of the triangular splint 8 through a parent and child screw, and a narrow slot is opened on the connecting support, one end of which is connected to the pull rope of the swing arm of the servo 6, and the other end thereof passes through the narrow slot and bypasses the parent and child screw to be connected to the third spring 12. The swing arm is rotated by the servo 6 to pull the pull rope, thereby changing the elongation of the spring, thereby changing the stiffness of the tensile structure to achieve the effect of adjusting the gripping performance such as the clamping force, anti-interference ability and anti-collision ability of the gripper.

[0041] In this embodiment, the tensioning bistable mechanism 3 comprises a trigger lever 7, a pair of triangular clamps 8, a pair of floating plates 9, and three sets of springs. This mechanism provides the gripper with bistable characteristics and allows for adjustable gripping performance. The two first springs 10 of the first set of springs have their ends attached to the nodes on the hypotenuse of the triangular clamps 8 via key screws. The two second springs 11 of the second set of springs have their ends attached to the outer nodes of the floating plate 9 via key screws. One end of the two third springs 12 of the third set of springs is attached to the narrow slot in the middle of the outer node of the floating plate 9 via key screws. The other end is connected to a pull rope that passes through the narrow slot of the base's connecting support and ultimately connects to the swing arm of the servo 6.

[0042] like Figure 3 As shown, triangular clamping plate 8 is a double-layer hollow structure with a main body in the form of a right triangle. The upper end of the triangular clamping plate is flat and fixedly connected to the flexible clamping jaw 4, serving as a connection between the tensioning bistable mechanism 3 and the flexible clamping jaw 4. A second connection node is provided on the hypotenuse of triangular clamping plate 8. This second connection node is rotatably connected to the fourth connection node of the floating plate and one end of the first spring 10 via a threaded screw. When the gripper is closed, triangular clamping plate 8 drives the flexible clamping jaw 4 to close from both sides.

[0043] like Figure 4 As shown, in this embodiment, the swimming plate 9 is a triangular structure, and the swimming plate body passes through the two layers of the triangular splint with a double-layer hollow structure. The fifth connection node of the swimming plate 9 is rotatably connected to the second springs 11 on the front and rear sides and the third spring 12 in the middle through a parent-child screw.

[0044] like Figure 5 As shown, the trigger lever 7 has a central pivoting connection connected to the floating plates 9 on either side. Its lower portion is a strip-shaped chute, within which the top block of the electric push rod 5 can slide. The trigger lever 7 can move with two degrees of freedom within the annular limit groove of the base. The upper end of the trigger lever 7 is connected to the trigger surface via a straight rod. The trigger surface is slightly curved to adapt to the shape of the object being grasped, and a silicone layer is provided on the trigger surface to reduce direct impact on the object. When the trigger surface of the trigger lever 7 is struck by an object, the trigger lever 7 moves downward. If the object's kinetic energy exceeds the potential energy barrier, the gripper quickly closes to complete the grasp.

[0045] The flexible gripper 4 is used to achieve flexible and adaptive gripping of the object. Figure 6 As shown, the lower end of the flexible clamping jaw 4 is a double-layer structure, clamped on both sides of the upper plane of the triangular clamping plate and fixed to the upper plane of the triangular clamping plate by fasteners. The upper portion of the flexible clamping jaw 4 adopts a fin-ray-like structure, with multiple ribs at gradually varying angles arranged inside to adapt the deformation capacity of the fin ray at different distances to the gripper's gripping force. The flexible clamping jaw 4 has a serrated structure on the contact surface with the grasped object to increase friction and load capacity. The flexible clamping jaw 4 is provided with a buffering boss at the contact point with the trigger lever to cushion the collision between the flexible clamping jaw 4 and the trigger lever 7 when the gripper is closed.

[0046] In this embodiment, the flexible clamping claw is made of TPU material through 3D printing. The base, triangular clamping plate, floating plate, and trigger rod are all made of PLA material through 3D printing.

[0047] The working principle of the tensegrity structure bistable flexible gripper provided in this embodiment is further explained below.

[0048] like Figure 7 As shown, the gripper can be pushed out by the electric push rod 5, pushing the trigger rod 7 to move upward, thereby actively opening the gripper, and then the electric push rod 5 is retracted downward to the triggering position; through the collision of the grasped object, the trigger rod 7 moves downward, thereby triggering the tensegrity bistable structure, and the structure quickly releases the potential energy stored inside it to complete the rapid grasping process; the electric push rod 5 can also continue to retract to drive the trigger rod 7 to move downward, actively triggering the tensegrity bistable structure to complete the grasping.

[0049] like Figure 8 As shown, the steering gear 6 rotates the swing arm to pull the pull rope to change the elongation of the spring, thereby changing the stiffness of the tensegrity structure and the overall structural stiffness, clamping force, anti-interference ability and anti-collision energy of the gripper.

[0050] In this embodiment, the servo 6 rotates the swing arm to reduce the elongation of the third spring 12, which can increase the clamping force of the gripper; increasing the elongation of the third spring 12 and increasing the stiffness of the tensegrity structure can enhance the gripper's ability to absorb energy in a collision and its ability to resist collision.

[0051] In this embodiment, retracting the electric push rod 5 can pull the trigger rod 7 toward the trigger position, reducing the required potential energy barrier; extending the electric push rod 5 can increase the potential energy barrier, reduce the possibility of the bistable structure being falsely triggered under vibration or other interference, and improve the anti-interference ability.

[0052] The mathematical simulation curve of the gripping gesture energy barrier adjustment is as follows: Figure 9 As shown. Figure 9 A set of control curves are shown in FIG, and the total potential energy curve, the third spring potential energy curve, the trigger point, and the potential energy barrier ΔE are indicated.

[0053] In this embodiment, we analyze the case where the swing arm of the servo 6 is adjusted to increase the elongation of the third spring 12. In this case, the potential energy curve of the adjusted third spring 12 will be higher than the reference curve, and the adjusted total potential energy curve will be improved. In addition, the adjusted potential energy barrier ΔE' is higher than ΔE.

[0054] In this embodiment, we analyze the case of retracting the electric push rod 5 to limit its opening angle; after limiting the position indicated by the right arrow in the reference curve to the position indicated by the left arrow, its potential energy barrier is reduced from ΔE to ΔE''.

[0055] like Figure 10 As shown, we obtained the mathematical simulation curve of the gripper's clamping torque with respect to the opening angle by derivation of the potential energy curve; after adjusting the servo 6 swing arm to increase the elongation of the third spring 12, its clamping torque was significantly reduced compared with the clamping torque curve of the control group.

[0056] The present invention provides a tensegrity structure bistable flexible gripper with adjustable gripping performance, which can achieve rapid gripping of target objects with the help of energy output during steady-state switching, and can be used for rapid gripping of dynamic targets, without the need for continuous energy input to maintain the gripper's opening or gripping state; the gripper can have a variety of adjustable gripping performances to cope with different gripping targets and different gripping environments through the adjustment of the electric push rod and the servo; the flexible clamping claws used can adapt to the shape of the gripped object for envelope gripping, thereby improving the gripping success rate and the weight of the grippable target, playing a buffering role during the gripping process, and protecting the gripped object; each component has low complexity, low cost, and is easy to control.

[0057] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other manner. Any person skilled in the art may utilize the above-disclosed technical content to modify or modify the present invention into equivalent embodiments. However, any simple modifications, equivalent variations, and modifications to the above embodiments that do not depart from the technical content of the present invention and are based on the technical essence of the present invention remain within the scope of protection of the present invention.

Claims

1. A tensegrity bistable flexible gripper with adjustable gripping performance, characterized in that: It includes a base, a driving module, a tensioning bistable mechanism and a pair of flexible clamps; the driving module includes an electric push rod and two servos, the electric push rod is installed in the middle of the base, and the two servos are symmetrically installed on the left and right sides of the base; the tensioning bistable mechanism includes a trigger rod, a pair of triangular splints, a pair of swimming plates and three sets of springs; the trigger rod is composed of a straight rod with a trigger surface on the upper part, an intermediate rotating connecting part and a lower strip slide; the upper end of the push rod of the electric push rod is connected with a top block, and the top block is embedded in the strip slide; the pair of triangular splints are symmetrically arranged on the left and right sides of the upper end of the base, and are rotatably connected to the rotating connecting nodes on the left and right sides of the upper end of the base through the first connecting node at the lower part; the pair of swimming plates are symmetrically arranged, and the two The two floating plates are rotatably connected to the rotating connection part of the trigger rod through the third connection node on the inner side thereof, and the two floating plates are rotatably connected to the second connection node on the corresponding triangular clamping plate through the fourth connection node on the upper part thereof; the two first springs are arranged front and back, and the left and right ends of the first springs are respectively rotatably connected to the second connection nodes on the two triangular clamping plates; the two second springs are arranged front and back, and the left and right ends of the second springs are respectively rotatably connected to the fifth connection nodes on the two floating plates; a pull rope is connected to each of the two servos, and the pull rope passes around the corresponding first connection node and is connected to one end of the third spring, and the other end of the third spring is rotatably connected to the fifth connection node on the corresponding floating plate; the pair of flexible clamps are symmetrically installed on the two triangular clamping plates.

2. A tensegrity structure bistable flexible gripper with adjustable gripping performance according to claim 1, characterized in that: The left and right sides of the base are respectively provided with several servo mounting through holes, the lower part of the base is provided with several push rod mounting through holes, and the upper part of the base is provided with a limiting slide groove; the two servos are symmetrically installed on the left and right sides of the base and are fixedly connected to the servo mounting through holes on the left and right sides of the base through fasteners; the electric push rod is installed in the middle of the base and the lower part thereof is fixedly connected to the push rod mounting through holes at the lower part of the base through fasteners; the push rod mounting through holes are also used to install the gripper at the end of a robotic arm or a drone; a slider is provided at the upper end of the push rod of the electric push rod, and a top block is connected to the slider, the slider slides up and down in the limiting slide groove, and the top block slides up and down in the strip slide groove.

3. The tensegrity structure bistable flexible gripper with adjustable gripping performance according to claim 1, characterized in that: Connecting supports are provided on the left and right sides of the upper end of the base, and the connecting supports are rotatably connected to the first connecting node at the lower part of the triangular splint through a parent and child screw. A narrow slot is provided on the connecting support, one end of which is connected to the pull rope of the servo swing arm, and the other end thereof passes through the narrow slot and bypasses the parent and child screw to be connected to the third spring.

4. The tensegrity structure bistable flexible gripper with adjustable gripping performance according to claim 1, characterized in that: The triangular splint is a double-layer hollow structure with a right-angled triangle as the main body. The upper end of the triangular splint is a plane and is fixedly connected to the flexible clamping claw. A second connection node is set on the hypotenuse of the triangular splint. The second connection node is rotatably connected to the fourth connection node of the floating plate and one end of the first spring through a parent and child screw.

5. The tensegrity structure bistable flexible gripper with adjustable gripping performance according to claim 4, characterized in that: The swimming plate passes through a triangular splint with a double-layer hollow structure, and the fifth connection node of the swimming plate is rotatably connected to the second springs on the front and rear sides and the third spring in the middle through a parent-child screw.

6. The tensegrity structure bistable flexible gripper with adjustable gripping performance according to claim 1, characterized in that: The trigger surface on the upper part of the trigger rod has a certain curvature to adapt to the shape of the grasped object, and a silicone layer is provided on the trigger surface to reduce direct impact on the grasped object.

7. The tensegrity structure bistable flexible gripper with adjustable gripping performance according to claim 1, characterized in that: The flexible clamp is used to achieve flexible and adaptive grasping of the grasped object. The lower end of the flexible clamp is fixedly connected to the upper plane of the triangular clamp by a fastener; the upper part of the flexible clamp adopts a fin-like structure, and a plurality of ribs with gradually changing angles are arranged inside it, so that the deformation ability of the fin at different distances is adapted to the clamping force of the gripper. The flexible clamp is provided with a serrated structure on the contact surface with the grasped object to increase friction and load capacity. The flexible clamp is provided with a buffer boss on the contact part with the trigger rod to buffer the collision between the flexible clamp and the trigger rod when the gripper is closed.

8. The tensegrity structure bistable flexible gripper with adjustable gripping performance according to claim 1, characterized in that: The flexible clamp is made of TPU material through 3D printing.

9. The tensegrity structure bistable flexible gripper with adjustable gripping performance according to claim 1, characterized in that: The base, triangular splint, swimming plate and trigger rod are all made of PLA material through 3D printing.

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