A multi-mode bistable flexible gripper for amphibious unmanned aerial vehicles

Abstract

This invention relates to the field of robotic arm technology, specifically disclosing a multi-mode bistable flexible gripper for amphibious unmanned aerial vehicles (UAVs), comprising a base, rope-driven soft fingers, a bistable actuation mechanism, and a trigger; at least two rope-driven soft fingers are rotatably disposed on the base; at least one bistable actuation mechanism is fixedly disposed on the base, and the bistable actuation mechanism and the trigger control the at least two rope-driven soft fingers to grasp and release objects; this multi-mode bistable flexible gripper for amphibious UAVs has bistable characteristics, combined with both grasping and suction operation mechanisms, thus possessing multi-mode operation capabilities, suitable for grasping more types of objects and more complex environments.

Description

Technical Field

[0001] This invention relates to the field of robotic arm technology, specifically to a multi-mode bistable flexible gripper for amphibious unmanned aerial vehicles. Background Technology

[0002] Amphibious unmanned aerial vehicles (UAVs) are characterized by their wide operating range, strong environmental adaptability, and ease of deployment. Combining amphibious UAVs with the operational capabilities of robotic grippers will further expand the application scope of amphibious UAVs, such as aerial landing and non-destructive underwater sampling. In aerial environments, the UAV gripper needs a rapid response mechanism to quickly grasp branches or other natural structures, helping the UAV to take off and land stably and reliably, and to establish a foothold. In underwater environments, the UAV gripper is required to be flexible and adaptable to achieve non-destructive sampling of vulnerable organisms.

[0003] Clearly, the requirements for aerial habitat and underwater biological sampling are different, so it is necessary to design a gripper suitable for amphibious drones. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a multi-mode bistable flexible gripper for amphibious unmanned aerial vehicles, which has bistable characteristics and is equipped with both grasping and suction operation mechanisms, thus having multi-mode operation capability and being suitable for grasping more types of objects and more complex environments.

[0005] To solve the above problems, the present invention adopts the following technical solution:

[0006] An embodiment provides a multi-mode bistable flexible gripper for amphibious unmanned aerial vehicles, comprising: a base, at least two rope-driven soft fingers, at least one bistable actuation mechanism, and at least one trigger.

[0007] The at least two rope-driven soft fingers are rotatably mounted on the base.

[0008] The at least one bistable actuation mechanism is fixedly disposed on the base.

[0009] In some operating modes, the at least one bistable actuation mechanism is used to self-actuate the at least two rope-driven soft fingers to grasp and release objects.

[0010] In some operating modes, the at least one bistable actuation mechanism is used to be triggered by the at least one trigger to actuate the at least two cord-driven soft fingers to grasp and release an object.

[0011] In some operating modes, the at least one bistable actuation mechanism is provided with partial triggering force by the at least one trigger when it actuates the at least two cord-driven soft fingers to grasp and release an object.

[0012] The trigger is equipped with at least one adsorption mechanism for adsorbing items.

[0013] The present disclosure provides at least one embodiment of a multi-mode bistable flexible gripper for an amphibious unmanned aerial vehicle, wherein the bistable actuation mechanism has an open steady state and a closed steady state, and the bistable actuation mechanism includes: a flexible member and at least two retainers.

[0014] The flexible component has a driving air chamber, an air hole, and at least two first trigger blocks.

[0015] The at least two retainers are disposed at the bottom of the flexible member.

[0016] The driving air chamber is connected to the air hole.

[0017] The at least two first trigger blocks are located at the bottom of the flexible element.

[0018] The at least two rope-driven soft fingers have drive ropes, and the drive ropes of the at least two rope-driven soft fingers are connected to the at least two retainers one by one.

[0019] When the pressure inside the drive air chamber is adjusted to negative and the flexible element contracts, the at least two first trigger blocks guide the contraction of the flexible element.

[0020] When the pressure inside the drive air chamber is adjusted to negative and the flexible element contracts, the at least two retainers are configured to gradually move closer together as the flexible element contracts, causing the rope-driven soft finger to make a grasping motion.

[0021] In at least one embodiment of the present disclosure, a multi-mode bistable flexible gripper for an amphibious unmanned aerial vehicle is provided, wherein the bistable actuation mechanism further includes at least one elastic element.

[0022] The at least one elastic element is stretched and fixedly disposed on the at least two fasteners.

[0023] The first trigger block has an abutting surface, and the abutting surfaces of adjacent first trigger blocks abut against each other to balance the elastic force of the at least one elastic element.

[0024] When the adjacent first trigger block guides the contraction of the flexible element, the at least one elastic element releases stored elastic potential energy to provide kinetic energy for the movement of the trigger.

[0025] In at least one embodiment of the present disclosure, a multi-mode bistable flexible gripper for an amphibious unmanned aerial vehicle is provided, wherein a connecting shaft is provided at the bottom of the flexible component, and the connecting shaft is used to provide support for the bottom of the flexible component.

[0026] The retainer is fixedly connected to the connecting shaft, which is located to the side of the first trigger block.

[0027] In at least one embodiment of the present disclosure, a multi-mode bistable flexible gripper for an amphibious unmanned aerial vehicle is provided, wherein the trigger includes a connecting frame.

[0028] The connecting frame is configured to slide in connection with the base.

[0029] The second trigger block is fixedly mounted on the connecting frame.

[0030] The second trigger block is located below the first trigger block. The second trigger block is used to collide with the bottom of the flexible component to cause the bistable actuation mechanism to change from an open steady state to a closed steady state.

[0031] The adsorption mechanism is fixedly disposed on the second trigger block.

[0032] In at least one embodiment of the present disclosure, a multi-mode bistable flexible gripper for an amphibious unmanned aerial vehicle is provided, wherein the first trigger block is triangular prism-shaped, and the bottom surface of the first trigger block serves as the abutment surface.

[0033] The number of the first trigger blocks is even, and every two first trigger blocks form a group, with the two first trigger blocks in each group arranged symmetrically from left to right.

[0034] The adjacent first trigger blocks are arranged on the inner bottom surface of the driving air chamber with their bottom surfaces touching.

[0035] One side of the first trigger block is fixedly connected to the inner bottom surface of the driving air chamber.

[0036] In at least one embodiment of the present disclosure, a multi-mode bistable flexible gripper for an amphibious unmanned aerial vehicle is provided, wherein the rope-driven soft finger comprises: a finger body, an exoskeleton, and a fingertip.

[0037] The finger has a mounting groove.

[0038] The exoskeleton is inserted into the mounting slot.

[0039] The fingertip is fixedly positioned at the end of the finger body.

[0040] The outer frame is provided with perforations, and both the outer frame and the mounting slots are provided with multiple slots. The multiple mounting slots are distributed at equal intervals, and the outer frame is fixedly connected to the finger body.

[0041] The drive rope passes through the perforation.

[0042] One end of the drive rope is fixed to an exoskeleton adjacent to the fingertip, and the other end of the drive rope is fixed to the fixer.

[0043] In at least one embodiment of the present disclosure, a multi-mode bistable flexible gripper for an amphibious unmanned aerial vehicle is provided, wherein a guide rail is provided on the base, a slider is provided on the connecting frame, and the base and the connecting frame are slidably connected through the guide rail and the slider.

[0044] In at least one embodiment of the present disclosure, a multi-mode bistable flexible gripper for an amphibious unmanned aerial vehicle is provided, wherein the top of the flexible component is fixedly connected to the base.

[0045] In at least one embodiment of the present disclosure, a multi-mode bistable flexible gripper for an amphibious unmanned aerial vehicle is provided, wherein the first trigger block is an elastic body.

[0046] The beneficial effects of this invention are as follows:

[0047] It features multiple working modes, including passive trigger quick grip, active trigger quick grip, active trigger gentle grip, and adsorption mode. The passive trigger quick grip mode also allows for adjustable sensitivity, thus helping drones handle a wider variety of tasks.

[0048] The overall structure is relatively simple. By combining a miniature air pump and a pressure regulating valve, the movement of the gripper can be controlled. The control is simple and the installation is highly integrated. Attached Figure Description

[0049] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0050] Figure 1 This is a perspective view of a multi-mode bistable flexible gripper for an amphibious unmanned aerial vehicle (UAV) according to an embodiment.

[0051] Figure 2 This is a schematic diagram of the base structure.

[0052] Figure 3 A schematic diagram of the structure of a rope-driven soft finger.

[0053] Figure 4 This is a schematic diagram of the structure of the finger body.

[0054] Figure 5 This is a schematic diagram of the exoskeleton.

[0055] Figure 6 This is a schematic diagram of a bistable actuation mechanism.

[0056] Figure 7 This is a cross-sectional view of the flexible component.

[0057] Figure 8 This is a schematic diagram of the flexible component.

[0058] Figure 9 This is a schematic diagram of the fixture.

[0059] Figure 10 This is a schematic diagram of the steady-state transition of the multi-mode bistable flexible gripper used for amphibious unmanned aerial vehicles in this embodiment.

[0060] Figure 11 This is a schematic diagram of the trigger structure.

[0061] Figure 12 This is a schematic diagram of the second trigger block.

[0062] Figure 13 This is a cross-sectional view of the adsorption mechanism.

[0063] Figure 14 This is a schematic diagram of a passively triggered rapid grasping mode of a multi-mode bistable flexible gripper for an amphibious unmanned aerial vehicle, as shown in the embodiment.

[0064] Figure 15 This is a schematic diagram of an active-driven rapid grasping mode for a multi-mode bistable flexible gripper used in an amphibious unmanned aerial vehicle, as shown in the embodiment.

[0065] Figure 16 This is a schematic diagram of an active-driven gentle grasping mode of a multi-mode bistable flexible gripper for an amphibious unmanned aerial vehicle, as shown in the embodiment.

[0066] Figure 17 This is a schematic diagram of the absorption mode of a multi-mode bistable flexible gripper for an amphibious unmanned aerial vehicle (UAV) in one embodiment.

[0067] Figure 18 This is a schematic diagram of a gripping and suction hybrid mode of a multi-mode bistable flexible gripper for an amphibious unmanned aerial vehicle (UAV) as described in the embodiment.

[0068] In the picture:

[0069] 100. Base; 110. Mounting hole; 120. Tracheal inlet; 130. Guide rail; 140. Finger mounting position;

[0070] 200. Rope-driven soft finger; 210. Finger body; 211. Mounting slot; 220. Exoskeleton; 221. Perforation; 222. Locking hole; 230. Drive rope; 240. Finger tip;

[0071] 300. Bistable actuation mechanism; 310. Flexible component; 311. Mounting hole; 312. Shaft hole; 313. Air hole; 320. First trigger block; 330. Connecting shaft; 340. Fixer; 341. Assembly hole; 342. Slot; 343. Rope fixing hole; 350. Elastic element;

[0072] 400, Trigger; 410, Connector; 411, Second Trigger Block; 412, Slider; 420, Adsorption Mechanism; 421, Suction Cup Air Inlet; 422, Suction Cup Air Outlet. Detailed Implementation

[0073] The technical solutions in the embodiments will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments, not all embodiments.

[0074] like Figure 1 As shown, this embodiment provides a multi-mode bistable flexible gripper for amphibious unmanned aerial vehicles (UAVs), including a base 100, a tethered soft finger 200, a bistable actuation mechanism 300, and a trigger 400. The coordinated operation of the tethered soft finger 200 and the bistable actuation mechanism 300 ensures both speed and flexibility in gripping. The trigger 400 can either activate the adsorption mechanism on the bistable actuation mechanism 300 under external force or independently perform adsorption and detachment of objects.

[0075] like Figure 2 As shown, the base 100 is 3D printed from photosensitive resin and has mounting holes 110, an air tube inlet 120, a guide rail 130, and a finger mounting position 140. The mounting holes 110 are used to mount the bistable actuation mechanism 300 with bolts. One end of the external air tube passes through the air tube inlet 120 into the base 100, and the other end is connected to an air pump. The guide rail 130 provides guidance for the trigger 400, and the rope-driven soft finger 200 is fixed to the base 100 via the finger mounting position 140.

[0076] Figure 3 , Figure 4 , Figure 5 As shown, the rope-driven soft finger includes a finger body 210, an exoskeleton 220, a driving rope 230, and a fingertip 240.

[0077] The finger body 210 has a mounting groove 211; the fingertip 240 is fixedly disposed at the end of the finger body 210; wherein, the outer frame 220 is provided with a through hole 221, and both the outer frame 220 and the mounting groove 211 are provided with multiple, the multiple mounting grooves 211 are distributed at equal intervals, and the outer frame 220 is fixedly connected to the finger body 210; the drive rope 230 passes through the through hole 221; one end of the drive rope 230 is fixed to an outer frame 220 adjacent to the fingertip 240, and the other end of the drive rope 230 is fixed to the retainer 340.

[0078] The outer frame 220 has a locking hole 222, through which the finger 210 passes and the outer frame 220 is partially inserted into the mounting groove 211.

[0079] like Figure 6 , Figure 7 , Figure 8 , Figure 9 As shown, the bistable actuation mechanism 300 includes a flexible element 310, a first trigger block 320, a connecting shaft 330, a retainer 340, and an elastic element 350. The flexible element 310 is molded from silicone and has a driving air chamber, a mounting hole 311, a shaft hole 312, and an air hole 313. The first trigger block 320 is a triangular prism-shaped elastic block, with two blocks forming a group, bonded to the inner bottom surface of the flexible element 310 with their bases abutting each other using silicone adhesive. The two connecting shafts 330 are inserted into the bottom sides of the flexible element 310 through the two shaft holes 312. Each connecting shaft 330 has a retainer 340 at each end, and the retainers 340 are fixed together through mounting holes 341. The retainer 340 has a slot 342 and a rope fixing hole 343. The slot 342 is used to install a pre-stretched elastic element 350, and the end of the driving rope 230 is fixed in the rope fixing hole 343.

[0080] Figure 10 This is a schematic diagram of the steady-state switching mechanism of the bistable actuation mechanism 300. The bistable actuation mechanism 300 has two stable states: open and closed. When in the open state, it can switch to the closed state through passive triggering and active driving. Specifically, when the bottom of the flexible member 310 is impacted by an external collision, the first trigger block 320 will rotate with the bottom of the flexible member 310, reducing the contact surface and making it unable to provide sufficient force to balance the elastic force of the elastic element 350, leading to structural instability. This causes the elastic element 350 to recover its deformation and release its elastic potential energy. At this time, the bottom of the bistable actuation mechanism 300 contracts and folds, presenting a closed stable state. When a negative pressure is applied to the inside of the bistable actuation mechanism 300 to a certain extent through the air hole 313, the flexible member 310 will also contract and fold inward, causing the first trigger block 320 to rotate, thereby triggering the steady-state switching.

[0081] When in a closed steady state, when positive pressure is applied to the inside of the bistable actuation mechanism 300 through the air hole 313 to a certain extent, the flexible part 310 can expand and drive the first trigger block 320 to return to the posture of bottom edges abutting each other, and stretch the elastic element 350, thereby returning to the open steady state.

[0082] like Figure 11 , Figure 12 , Figure 13 As shown, the trigger 400 includes a connecting frame 410 and a second trigger block 411. The second trigger block 411 is fixedly disposed on the connecting frame 410 and is located below the first trigger block 320. A slider 412 is provided on the connecting frame 410, and the base and the connecting frame are slidably connected by a guide rail 130 and the slider 412.

[0083] When the second trigger block 411 contacts the object, the connecting frame 410 can move upward along the guide rail 130 and collide with the bottom of the bistable actuation mechanism 300, causing it to undergo a state transition.

[0084] The adsorption mechanism 420 has a suction cup air inlet 421 and a suction cup air outlet 422, and is mounted on the second trigger block 411. By applying negative or positive pressure to the suction cup air inlet 421, the adsorption or desorption of objects in contact with the suction cup air outlet 422 can be achieved. The suction cup air inlet 421 is connected to an air pump.

[0085] Since the multi-mode bistable flexible gripper for amphibious unmanned aerial vehicles provided in the embodiment has bistable characteristics and is equipped with both grasping and suction operation mechanisms, it has multi-mode operation capability and is suitable for grasping more types of objects and more complex environments. Some working modes will be listed below to further illustrate the principle of the multi-mode bistable flexible gripper for amphibious unmanned aerial vehicles provided in the embodiment.

[0086] Working Mode 1:

[0087] Passively triggered fast capture mode, such as Figure 14As shown. When the trigger 400 is subjected to an external impact, such as when the suction cup of the drone comes into contact with a natural structure like a tree branch during descent, the trigger 400 moves upward and collides with the bottom of the bistable actuation mechanism 300, causing the bistable actuation mechanism 300 to change from an open state to a closed state. The deformation generated in this process can drive the drive rope 230 to tighten, causing the rope-driven flexible finger 200 to bend inward, completing the grasping action. This function is suitable for helping drones achieve rapid landing and resting. In addition, by adjusting the air pressure in the flexible component 310, the triggering force required for switching between bistable states can be changed to adapt to different environments or for grasping different objects. For example, in high wind and wave environments, positive pressure can be applied to increase the triggering force of the gripper, so as to prevent the gripper from accidentally activating due to external environmental interference; when grasping moving objects with small momentum, a smaller negative pressure is applied to reduce the triggering force of the gripper, which can reduce the energy input required for the gripper to grasp, thereby adapting to the dynamic grasping of objects with small momentum.

[0088] Working Mode 2:

[0089] Actively trigger the fast capture mode, such as Figure 15 As shown, when a certain negative pressure is applied to the flexible component 310 through the air vent 313, the bistable actuation mechanism 300 can be actively driven to change from an open state to a closed state, thereby driving the drive rope 230 to drive the rope-driven soft finger 200 to perform a grasping action. This mode does not rely on collisions with external objects and is suitable for UAVs to actively and quickly grasp objects.

[0090] Working Mode 3:

[0091] Actively trigger the gentle grasping mode, such as Figure 16 As shown, a negative pressure is applied beforehand to bring the bistable actuator 300 into a closed, stable state, at which point the gripper is in a grasping, closed state. Applying a small positive pressure to the flexible component 310 through the air vent 313 slightly expands the bottom of the bistable actuator 300, thereby relaxing part of the drive rope 230 and partially opening the rope-driven soft fingers 200, allowing an object to enter between the fingers. Then, the applied positive pressure is gradually reduced, causing the rope-driven soft fingers 200 to slowly press against the grasped object, thus completing a gentle grasp. This mode is suitable for assisting UAVs in non-destructive sampling tasks on vulnerable organisms.

[0092] Working Mode 4:

[0093] Absorption mode, such as Figure 17 As shown. The suction mechanism 420 is driven solely by the suction cup air inlet 421 to adsorb objects. This mode is suitable for grasping flat objects, as well as objects that are too small or too large for the gripper.

[0094] Working Mode 5:

[0095] Grab and suck hybrid modes, such as Figure 18As shown. Simultaneously, negative pressure is applied to the flexible component 310 and the suction mechanism 420 through the air vent 313 and the suction cup air inlet 421, respectively, causing the gripper to perform both gripping and suction operations simultaneously. This mode can improve the gripper's gripping stability. For example, when a drone lands on a smooth surface, a simple gripping mode cannot provide sufficient friction to ensure the drone's stability; the hybrid gripping and suction mode can additionally increase the suction force of the suction cup, thus increasing gripping stability.

[0096] Although embodiments of this application have been shown and described above, the scope of protection of this invention is not limited thereto. Any variations or substitutions that can be conceived without inventive effort should be covered within the scope of protection of this invention. Unless expressly stated otherwise, no element, action or instruction used herein should be construed as critical or necessary.

Claims

1. A multi-mode bistable flexible gripper for amphibious unmanned aerial vehicles, characterized in that, include: Base; At least two rope-driven soft fingers are rotatably configured on the base; At least one bistable actuation mechanism is fixedly disposed on the base; At least one trigger; Wherein, the at least one bistable actuation mechanism is used to self-actuate the at least two rope-driven soft fingers to grasp and release objects, and / or The at least one bistable actuation mechanism is configured to be triggered by the at least one trigger to actuate the at least two cord-driven soft fingers to grasp and release an object, and / or When the at least one bistable actuation mechanism actuates the at least two rope-driven soft fingers to grasp and release an object, it is provided with a partial triggering force by the at least one trigger. The trigger is provided with at least one adsorption mechanism for adsorbing items; The bistable actuation mechanism has an open steady state and a closed steady state, and the bistable actuation mechanism includes: The flexible component has a driving air chamber, an air hole, and at least two first trigger blocks; and At least two retainers are configured at the bottom of the flexible member; The driving air chamber is connected to the air hole; The at least two first trigger blocks are located at the bottom of the flexible component; The at least two rope-driven soft fingers have drive ropes, and the drive ropes of the at least two rope-driven soft fingers are connected to the at least two retainers one by one; When the pressure inside the drive air chamber is adjusted to negative and the flexible element contracts, the at least two first trigger blocks guide the contraction of the flexible element; the at least two retainers are configured to gradually move closer together as the flexible element contracts, causing the rope-driven soft finger to make a grasping motion. The bistable actuation mechanism further includes: At least one elastic element is stretched and fixedly disposed on the at least two retainers; The first trigger block has an abutting surface, and the abutting surfaces of adjacent first trigger blocks abut against each other to balance the elastic force of the at least one elastic element; When the adjacent first trigger block guides the contraction of the flexible element, the at least one elastic element releases stored elastic potential energy to provide kinetic energy for the movement of the trigger.

2. The multi-mode bistable flexible gripper for amphibious unmanned aerial vehicles according to claim 1, characterized in that, The bottom of the flexible component is provided with a connecting shaft, which is used to provide support for the bottom of the flexible component. The retainer is fixedly connected to the connecting shaft, which is located to the side of the first trigger block.

3. A multi-mode bistable flexible gripper for amphibious unmanned aerial vehicles according to claim 2, characterized in that, The trigger includes: The connecting frame is configured to slide in connection with the base; as well as The second trigger block is fixedly configured on the connecting frame; The second trigger block is located below the first trigger block, and the second trigger block is used to collide with the bottom of the flexible component to cause the bistable actuation mechanism to change from an open stable state to a closed stable state. The adsorption mechanism is fixedly disposed on the second trigger block.

4. A multi-mode bistable flexible gripper for amphibious unmanned aerial vehicles according to claim 3, characterized in that, The first trigger block is triangular prism-shaped, and the bottom surface of the first trigger block serves as the contact surface; The first trigger block has an even number, and every two first trigger blocks form a group, with the two first trigger blocks in each group arranged symmetrically from left to right; The adjacent first trigger blocks are arranged with their bottom surfaces touching on the inner bottom surface of the driving air chamber; One side of the first trigger block is fixedly connected to the inner bottom surface of the driving air chamber.

5. A multi-mode bistable flexible gripper for amphibious unmanned aerial vehicles according to claim 2, characterized in that, The rope-driven soft finger includes: The finger body has a mounting slot; The outer frame is inserted into the mounting slot; and The fingertip is fixedly positioned at the end of the finger body; The outer frame is provided with perforations, and both the outer frame and the mounting slots are provided with multiple slots. The multiple mounting slots are distributed at equal intervals, and the outer frame is fixedly connected to the finger body. The drive rope passes through the perforation; One end of the drive rope is fixed to an exoskeleton adjacent to the fingertip, and the other end of the drive rope is fixed to the fixer.

6. A multi-mode bistable flexible gripper for amphibious unmanned aerial vehicles according to claim 3, characterized in that, The base is provided with a guide rail, and the connecting frame is provided with a slider. The base and the connecting frame are slidably connected through the guide rail and the slider.

7. A multi-mode bistable flexible gripper for amphibious unmanned aerial vehicles according to claim 2, characterized in that, The top of the flexible component is fixedly connected to the base.

8. A multi-mode bistable flexible gripper for amphibious unmanned aerial vehicles according to claim 4, characterized in that, The first trigger block is an elastic body.

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