Flexible bionic adhesion clamping jaw and robot

Abstract

The flexible bionic adhesion clamping jaw comprises a clamping jaw body, the clamping jaw body comprises a fingertip and a driving connecting rod set, the fingertip is installed at the tail end of the driving connecting rod set, a flexible gecko bionic material is installed on the grabbing face of the inner side of the fingertip, the clamping jaw body has a parallel grabbing state and an included angle grabbing state, and in the parallel grabbing state, the flexible gecko bionic material is attached to the clamping jaw body. The two fingertips are parallel to each other, and in the included angle grabbing state, the two fingertips oppositely extend outwards, and the materials are embedded into the flexible gecko biomimetic materials on the grabbing faces of the inner sides of the fingertips. The flexible gecko biomimetic material is combined to the fingertips, the fingertips form an inner buckling state during grabbing, and compared with a traditional industrial clamping jaw, the flexible contact increases the contact area, the gecko material increases the friction coefficient, so that the output requirement of clamping force can be lowered under the certain grabbing firmness target, and the clamping force can be increased; and meanwhile, the grabbing firmness under the condition of limited clamping force can be improved, and fragile and easy-to-deform objects can be better protected.

Description

Technical Field

[0001] This invention relates to the field of robotics, specifically to a flexible biomimetic adhesive gripper and robot. Background Technology

[0002] Robots equipped with gripping devices have been widely used in various fields such as industrial manufacturing and logistics. With continuous technological advancements, the application scenarios for robots are becoming increasingly diverse. However, current robot gripping modes are relatively simple and cannot effectively adapt to multiple scenarios.

[0003] Therefore, gecko-inspired biomimetic materials are applied to the design of various robotic grippers. These gecko-adhesive grippers can grasp objects at a certain opening angle (not necessarily parallel). In this case, thanks to the extremely high coefficient of friction of the gecko material, the frictional force it provides is far greater than the squeezing force exerted by the jaws on the object in the direction of the gripper opening when gripping at an angle. This principle allows the gecko grippers to stably grasp objects with a "V"-shaped opening, thus achieving the effect of grasping objects larger than the opening of the jaws.

[0004] Patent document CN115674251A discloses a grasping device and a robot equipped with the grasping device, such as Figure 1 As shown, it features a rigid fingertip gripping mode and a "V-shaped" opening gripping mode with side links incorporating gecko-inspired materials. This technology applies the fingertips and links separately to different gripping modes. The rigid fingertip gripping mode is not suitable for gripping easily deformable or fragile objects; while the "V-shaped" arrangement of the side links with gecko-inspired materials lacks the action of the fingertips at the far end of the gripper when gripping large objects, resulting in poor gripping load capacity and stability. Furthermore, because it only grips objects through the side links, although it uses gecko-inspired materials, it still requires a relatively high output of clamping force. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the purpose of this invention is to provide a flexible biomimetic adhesive gripper and robot.

[0006] The flexible biomimetic adhesive gripper provided by the present invention includes a pair of gripper bodies, each gripper body including a fingertip and a drive linkage assembly. The fingertip is mounted at the end of the drive linkage assembly, and the drive linkage assembly is configured to drive the movement and rotation of the fingertip by rotating the first linkage located at the head end. The gripping surface on the inner side of the fingertips is equipped with flexible gecko-inspired material. The gripper body includes a parallel gripping state and an angled gripping state. In the parallel gripping state, the two fingertips are parallel to each other. In the angled gripping state, the two fingertips are relatively outward. The material is embedded in the flexible gecko-inspired material on the gripping surface on the inner side of the fingertips.

[0007] Preferably, the drive linkage assembly includes a first link, a second link, a third link, and a fourth link; One end of the first link is connected to the drive device, the other end of the first link is hinged to one end of the second link, the other end of the second link is hinged to one end of the third link, the other end of the third link is connected to the fingertip, one end of the fourth link is hinged to the middle of the third link, and the other end of the fourth link is hinged to the housing of the gripper body. The first link serves as a drive link, used to rotate the fingertip inward and outward. Parallel gripping state: The first link and the second link move to the parallel limit, so that the line connecting the beginning and end of the first link and the second link is parallel to the fourth link and has the same length. At this time, the two fingertips are parallel to each other. Angle gripping state: When the second and third links move to the angle limit position, there is an outward folding angle between the two fingertips.

[0008] Preferably, an elastic covering layer is installed on the grasping surface on the inner side of the fingertip, and the flexible gecko-inspired material is disposed on the elastic covering layer.

[0009] Preferably, the elastic covering layer comprises a sponge or an air bladder.

[0010] Preferably, an adaptive locking mechanism is provided between the first link and the second link, or an adaptive locking mechanism is provided between the fourth link and the housing of the gripper body; The adaptive locking mechanism is used to restrict the outward extension of the fingertips after they are inwardly engaged during the second grasping phase.

[0011] Preferably, the adaptive locking mechanism includes a locking device and a sliding pin; The locking device is fixedly installed inside the first link, and the slider pin is slidably installed inside the second link. The slider pin is configured such that when the fingertip is inwardly hooked into place, the slider pin slides to contact the locking device, thereby locking the first link and the second link, preventing the fingertip from turning outward. Alternatively, the locking device is fixedly installed on the housing of the gripper body, and the slider pin is slidably installed inside the fourth link. The slider pin is configured such that when the fingertip is inwardly engaged, the slider pin slides to contact the locking device, thereby locking the first link and the second link, preventing the fingertip from turning outward.

[0012] Preferably, the end of the slider pin has meshing teeth, and the exterior of the locking device has ratchet teeth. The meshing teeth are used to mesh with the ratchet teeth under the drive of the slider pin, thereby locking the connecting rod to be locked in the meshing direction and preventing it from rotating.

[0013] Preferably, the end of the slider pin has a first braking surface, and the outside of the locking device has a second braking surface; The first braking surface is used to fit against the second braking surface under the action of the slider pin, thereby locking the connecting rod to be locked by friction.

[0014] The robot provided by the present invention employs the aforementioned flexible biomimetic adhesive gripper.

[0015] Preferably, the robot includes one or more robotic arms, the ends of which are equipped with the flexible bionic adhesive grippers.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention combines flexible gecko-inspired material with fingertips, which form an inward-curving state when gripping. Compared with traditional industrial grippers, the flexible contact increases the contact area, and the gecko material increases the coefficient of friction. Therefore, it can not only reduce the output requirement of clamping force under a certain gripping firmness target, but also improve the gripping firmness under limited clamping force conditions, which helps to better protect fragile and easily deformable items.

[0017] 2. The passive adhesion characteristics of the gecko-inspired biomimetic material of this invention can simplify the power system of the gripper, eliminating the need for an additional air source or other power device.

[0018] 3. In this invention, the fingertip is installed at the farthest end of the entire drive linkage assembly, and the gripper linkage can simultaneously realize two gripping modes: the fingertip parallel gripping mode and the fingertip adaptive wrapping gripping mode. When gripping large objects, due to the action of the fingertip at the far end of the gripper, it can have better gripping load capacity and stability. Attached Figure Description

[0019] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a schematic diagram of the gripper structure in the prior art; Figure 2 This is a schematic diagram illustrating the working principle of the present invention in the parallel grasping state for grasping objects; Figure 3 This is a schematic diagram illustrating the working principle of the present invention in grasping objects at an angle. Figure 4 This is a schematic diagram illustrating the working principle of the present invention when switching to the parallel grasping state; Figure 5 This is a schematic diagram illustrating the working principle of the present invention when switching to the angled grasping state; Figure 6 This is a schematic diagram of the assembly of the state switching mechanism and the gripper body in this invention; Figure 7 This is a schematic diagram of the assembly of the adaptive locking mechanism and the gripper body in this invention. Figure 1 ; Figure 8 for Figure 7 A schematic diagram of the adaptive locking mechanism when it triggers the locking state. Figure 9 This is a schematic diagram of the adaptive locking mechanism in this invention; Figure 10 This is a schematic diagram of the locking principle of the adaptive locking mechanism in this invention; Figure 11 This is a schematic diagram of the assembly of the adaptive locking mechanism and the gripper body in this invention. Figure 2 .

[0020] The diagram shows: Detailed Implementation

[0021] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0022] This invention discloses a flexible biomimetic adhesive gripper and robot. By combining flexible gecko-inspired material with the fingertip, the fingertip forms an inward-curling state when gripping. Compared with traditional industrial grippers, the flexible contact increases the contact area, and the gecko material increases the coefficient of friction. Therefore, it can not only reduce the output requirement of the gripping force under a certain gripping firmness target, but also improve the gripping firmness under limited gripping force conditions, which helps to better protect fragile and easily deformable items.

[0023] The gripper disclosed in this invention has flexible gecko-inspired material installed on its fingertips, possessing the advantages of other gecko adhesive grippers. The gripper linkage can switch its arrangement during movement to achieve two gripping modes: (1) parallel gripping mode with fingertips; (2) adaptive wrapping gripping mode with the combined action of fingertips and knuckle linkages.

[0024] Taking the two-finger gripper structure as an example, each fingertip link is a five-bar linkage. The first link 1 is the drive link, the fingertip 10 and the third link 3 are fixedly installed, and the hinge points at both ends of the fifth link 5 are fixed. Specifically, the proximal end of the first link 1 is connected to the drive device, the distal end of the first link 1 is hinged to the proximal end of the second link 2, the distal end of the second link 2 is hinged to the proximal end of the third link 3, and the distal end of the third link 3 is used to connect to the fingertip 10; the distal end of the fourth link 4 is hinged to the middle of the third link 3. It should be noted that "middle" here does not refer to the exact center position, but rather to the middle position of the third link 3 excluding the end. The proximal end of the fourth link 4 is hinged to the housing 17 of the gripper body, and the two ends of the fifth link 5 are respectively hinged to the proximal ends of the first link 1 and the fourth link 4, forming fixed hinge points. The first link 1 and the second link 2 are configured such that when the first link 1 and the second link 2 move to the parallel limit position, the line connecting the beginning and end of the first link 1 and the second link 2 is parallel to the fourth link 4, and the third link 3 is parallel to the fifth link 5, thus forming a parallel four-bar linkage. This changes to "parallel mode," corresponding to the grasping mode (1), as shown below. Figure 2 As shown. This mode is similar to the parallel two-finger gripper, capable of grasping small or flat objects. The fingertips 10 are equipped with flexible gecko-inspired materials and elastic materials such as sponges and airbags, providing good coverage and cushioning performance. When the second link 2 and the third link 3 are collinear or form a large angle, it becomes the "angle mode", corresponding to the grasping mode (2), such as Figure 3 As shown. In this mode, the fingertips extend outwards, allowing you to grasp larger objects, such as spherical or cylindrical objects.

[0025] In the angled gripping state, the two fingertips 10 extend outwards relative to each other, and the material is embedded in the flexible gecko-inspired material on the inner gripping surface of the fingertips 10. Compared with traditional industrial grippers, the flexible contact increases the contact area, and the gecko material increases the coefficient of friction. Therefore, it can not only reduce the output force required for gripping under a certain gripping strength target, but also improve the gripping strength under limited gripping force conditions, which helps to better protect fragile and deformable items. Furthermore, based on the passive adhesion characteristics of the gecko-inspired material, the power system of the gripper can be simplified, without the need for an additional air source or other power device. The following provides further explanation regarding the "angle mode": Figure 4As shown, the fourth link 4 serves as a finger joint link, with a gripping part on its inner side. In the angled gripping mode, the gripping process consists of two stages: In the first stage, the first link 1 swings outward until the angle between it and the second link 2 is the first angle, the fingertip 10 extends outward, and the gripping part on the inner side of the fourth link 4 contacts the material. In the second stage, the first link 1 swings inward, causing the fingertip 10 to curl inward until both the fingertip 10 and the gripping part on the inner side of the fourth link 4 simultaneously contact the material. Preferably, the first angle is 60°-90°, and the second angle is 100°-180°. When gripping an object in the "angled mode," thanks to the five-link configuration and the less constrained link swing angle, the fourth link 4 and the fingertip can contact the object's surface sequentially, forming a curled-in state that conforms to the object's shape. This state helps increase the contact area between the fingertip and the object, improving the adhesion between the gecko-inspired material and the object's surface, thereby enhancing the friction between them and ultimately improving gripping performance.

[0026] To enable the gripper to flexibly switch between a parallel fingertip gripping mode and an adaptive wrapping gripping mode during movement, a first elastic limiting member 11 is installed on the inner side of the hinge point between the fourth link 4 and the housing 17. The first elastic limiting member 11 is configured such that when the fourth link 4 swings to a first angle with the horizontal direction under the drive of the first link 1, its inward swing is blocked by an elastic force. A second elastic limiting member 13 is installed on the outer side of the hinge point between the fourth link 4 and the housing 17. The second elastic limiting member 13 is configured such that when the fourth link 4 swings to a second angle with the horizontal direction under the drive of the first link 1, its outward swing is blocked by an elastic force. The first angle is greater than the second angle. The specific values ​​of the first angle and the second angle can be adjusted according to different gripping requirements. In a preferred embodiment, the first angle is 30°-45° and the second angle is 5°-20°. A parallel limiting member 12 is installed between the first link 1 and the second link 2. The parallel limiting member 12 is configured such that when the first link 1 swings inward to the parallel limit with the second link 2, the line connecting the beginning and end of the first link 1 and the second link 2 remains parallel to the fourth link 4. An angle limiting member 14 is installed between the second link 2 and the third link 3. The angle limiting member 14 is configured such that when the second link 2 swings inward to the angle limit with the third link 3, the second link 2 and the third link 3 maintain a limit angle state. The gripper body includes a parallel gripping state and an angled gripping state. When switching to the parallel gripping state, the first link 1 swings inward, and the fourth link 4 is blocked by the elastic force under the action of the first elastic limiter 11 until the first link 1 and the second link 2 move to the parallel limit position. The line connecting the beginning and end of the first link 1 and the second link 2 is parallel to the fourth link 4. At this time, the two fingertips 10 are parallel to each other. When switching to the angled gripping state, the first link 1 swings outward, and the fourth link 4 is blocked by the elastic force under the action of the second elastic limiter 13 until the second link 2 and the third link 3 move to the angle limit position. At this time, there is an outward folding angle between the two fingertips 10. In a preferred embodiment, both the first elastic limiting member 11 and the second elastic limiting member 13 are compression springs 19. When the fourth link 4 rotates inward, making the angle between the fourth link 4 and the horizontal direction greater than the first angle, the first elastic limiting member 11 is in a compressed state, applying a spring force to the fourth link 4 to prevent it from rotating inward. At this time, the gripper body switches to a parallel gripping state. When the fourth link 4 rotates outward, making the angle between the fourth link 4 and the horizontal direction less than the second angle, the second elastic limiting member 13 is in a compressed state, applying a spring force to the fourth link 4 to prevent it from rotating outward. At this time, the gripper body switches to an angled gripping state.

[0027] The following describes the gripper state switching process with reference to the attached diagram: Figure 4 As shown, in order to achieve free switching between "parallel mode" and "angle mode", a parallel limit is added to the first link 1 and the second link 2, and an elastic limit is added to the fourth link 4. When it reaches a certain angle, it swings inward and is blocked by the elastic force. The first link 1, as the driving link, continues to rotate inward. The first link 1 and the second link 2 gradually move to the parallel limit position, so that the line connecting the first link 1 and the second link 2 is parallel to the fourth link 4, and finally maintains a parallel state. At this time, the gripper switches to "parallel mode". like Figure 5 As shown, angle limits are added to the second link 2 and the third link 3, and another set of elastic limits is added to the fourth link 4. When a certain angle is reached, the outward swing is blocked by the elastic force. The first link 1, as the driving link, continues to rotate outward. The second link 2 and the third link 3 gradually move to the angle limit position and finally maintain that angle state. At this time, the gripper switches to "angle mode". Note that this is just one example of implementation.

[0028] In another preferred embodiment, both the first elastic limiting member 11 and the second elastic limiting member 13 are tension springs. When the fourth link 4 rotates inward, making the angle between the fourth link 4 and the horizontal direction greater than the first angle, the first elastic limiting member 11 is in a stretched state, applying a spring force to the fourth link 4 to prevent it from rotating inward. At this time, the gripper body switches to a parallel gripping state. When the fourth link 4 rotates outward, making the angle between the fourth link 4 and the horizontal direction less than the second angle, the second elastic limiting member 13 is in a stretched state, applying a spring force to the fourth link 4 to prevent it from rotating outward. At this time, the gripper body switches to an angled gripping state.

[0029] Regarding the above-mentioned scheme using a compression spring 19 as an elastic limiting member, the following implementation method for the mode switching mechanism is further proposed: a side cover 18 is installed on the side of the fourth link 4; the first elastic limiting member 11 and the second elastic limiting member 13 are respectively installed in the first channel and the second channel arranged in the side cover 18; a first cylindrical pin 21 is provided on the inner side of the hinge point between the fourth link 4 and the housing 17, abutting against the top end of the first elastic limiting member 11; a second cylindrical pin 22 is provided on the outer side of the hinge point between the fourth link 4 and the housing 17, abutting against the top end of the second elastic limiting member 13; the bottom end of the first elastic limiting member 11 and the bottom end of the second elastic limiting member 13 abut against the bottom of the first channel and the bottom of the second channel, respectively.

[0030] In this design, a steel ball 21 is disposed between the top end of the first elastic limiting member 11 and the first cylindrical pin 21, and is slidably disposed in the first channel to compress the first elastic limiting member 11 under the action of the first cylindrical pin 21. Similarly, a steel ball 21 is disposed between the top end of the second elastic limiting member 13 and the second cylindrical pin 22, and is slidably disposed in the second channel to compress the second elastic limiting member 13 under the action of the second cylindrical pin 22. The top of the first channel has an arc corresponding to the movement trajectory of the steel ball 21 at the top of the first elastic limiting member 11; the top of the second channel has an arc corresponding to the movement trajectory of the steel ball 21 at the top of the second elastic limiting member 13.

[0031] The bottom of the first channel is provided with a first adjusting screw, and the bottom end of the first elastic limiting member 11 abuts against the first adjusting screw through a steel ball 21. The first adjusting screw is used to adjust the tightness of the first elastic limiting member 11. The bottom of the second channel is provided with a second adjusting screw, and the bottom end of the second elastic limiting member 13 abuts against the second adjusting screw through a steel ball 21. The second adjusting screw is used to adjust the tightness of the second elastic limiting member 13.

[0032] like Figure 6As shown, two sets of compression springs 19 are centrally symmetrically installed on both the inner and outer sides of the fourth link 4 in channels arranged within the side cover 18. Each spring has a steel ball 20 at both ends; one end is adjusted for tension via a set screw, and the other end can contact the cylindrical pin 21 mounted on the fourth link 4. The side cover 18 is mounted on the housing 17 of the gripper. As described in the previous implementation method, when the fourth link 4 rotates counterclockwise, the cylindrical pin 21 contacts the steel ball 20 and compresses the two sets of inner springs, the gripper switches to "parallel mode"; when the fourth link 4 rotates clockwise, the cylindrical pin 21 contacts the steel ball 20 and compresses the two sets of outer springs, the gripper switches to "angled mode." The steel ball 20 converts the circular motion trajectory of the link into the linear motion trajectory of the spring. Besides the above implementation, the compression springs can also be replaced with tension springs, applying elastic resistance from different installation directions to achieve mode switching.

[0033] This embodiment installs elastic and parallel limit switches on the linkage assembly, allowing two different linkage pairs to be parallelly limited. This enables the gripper to flexibly switch between a fingertip parallel gripping mode and an adaptive wrapping gripping mode during movement. In addition to retaining the parallel gripping method, a non-parallel gripping method is introduced, thereby increasing the gripper's gripping size. The parallel gripping mode is suitable for gripping items of different thicknesses, while the adaptive wrapping gripping mode is suitable for gripping large objects.

[0034] When the gripper is in "angle mode" to grasp an object, due to the under-constraint of the linkage mechanism, the fourth link 4 and the fingertip 10 can adhere to the object surface, achieving an adaptive covering state. However, under the influence of load, the angle of the under-constrained linkage mechanism may change after grasping the object, causing the gripper to disengage from the adaptive covering state. Therefore, this invention proposes an adaptive locking method for the gripper's adaptive covering grasping mode.

[0035] An adaptive locking mechanism is added to the gripper linkage. This adaptive locking mechanism includes a locking linkage group, a sliding pin 15, and a locking device 16. It is used to lock the linkage in the drive linkage group, preventing the linkage from rotating around its relative rotating portion. The locking device 16 is fixedly installed on the relative rotating portion of the linkage to be locked. The sliding pin 15 is installed at one end of the locking linkage group near the locking device 16 and slidably installed inside the linkage to be locked. The sliding pin 15 is configured to rotate around the locking linkage group and slide in a direction close to or away from the locking device 16. When its end contacts the locking device 16, it locks the linkage to be locked. Linkage; the end of the locking linkage group has a sixth link, which is hinged to the inside of the fingertip 10. The end of the sixth link has a pressing part 601 protruding from the clamping surface of the fingertip 10. The pressing part 601 is configured to: drive the sixth link to rotate relative to the fingertip 10 by pressing, and drive the slider pin 15 to slide toward the locking device 16 through the locking linkage group; when the pressing part 601 is pressed to a preset depth, the adaptive locking mechanism triggers the locking state, the slider pin 15 slides to the end and contacts the locking device 16, locking the link to be locked, so that the driving linkage group becomes fully constrained, and the fingertip 10 cannot be flipped outward.

[0036] The principle behind the adaptive locking mechanism that achieves adaptive locking without a force sensor is as follows: When the flexible gripping surface of the fingertip 10 continuously applies a gripping force to the object, the object's surface gradually embeds into the flexible gripping surface of the fingertip 10 as the gripping force is applied. The flexible material gradually deforms under the pressure of the object. As the object's embedding depth increases, the degree of deformation of the flexible material also gradually increases, and the contact area between the object and the object gradually increases. When the gripping force applied by the drive link to the fingertip 10 reaches a preset value, the object's embedding depth in the flexible material reaches a preset depth. At this time, the pressing part 601 of the sixth link 6 is triggered under the pressure of the object's outer surface, locking the link to be locked. This adaptive locking mechanism achieves gripping force sensing and link locking through simple mechanical transmission without the need for an additional force sensor. It should be noted that although the above purely mechanical adaptive locking mechanism can achieve adaptive locking without a force sensor, the use of a force sensor is not excluded in specific implementations. The choice between combining a force sensor and its use can be made based on specific circumstances.

[0037] The working principle of the above adaptive locking mechanism is as follows: taking the locking between the first link 1 and the second link 2 as an example, when locked, the distal hinge point of the first link 1 is located in the first position. In this position, the fingertip 10 is in an inward-curving state, adaptively enveloping and grasping the object. At this time, the second link 2 cannot swing relative to the first link 1. When unlocking is required, the first link 1 swings in the opposite direction of the applied clamping force until its distal hinge point swings to the second position, which is lower than the first position. At this time, the locking mechanism 16 disengages from the slider pin 15, and the first link 1 and the second link 2 are unlocked.

[0038] In a preferred embodiment, the sixth link 6 serves as a triggering mechanism and is installed within the cavity of the gripper fingertip 10. The sixth link 6 includes a pressing part 601 and a transmission part. The transmission part and the pressing part 601 form an L-shaped structure, and the junction of the transmission part and the pressing part 601 forms a fixed hinge point with the inner wall of the cavity of the fingertip 10. The proximal part of the transmission part extends away from the gripping surface of the fingertip 10 and is connected to the slider pin 15 through a transmission assembly. The transmission part is configured such that when the pressing part 601 is pressed, it rotates around the fixed hinge point, and the proximal end of the transmission part rotates and moves towards the locking device 15. An elastic element is also provided between the back of the pressing part 601 and the fingertip 10 to drive the pressing part 601 to reset when the adaptive locking mechanism is unlocked, so that it protrudes again from the flexible gripping surface of the fingertip 10.

[0039] The end of the slider pin 15 has a meshing tooth 1501, and the outside of the locking device 16 has a ratchet tooth surface 1601; the meshing tooth 1501 is used to mesh with the ratchet tooth surface 1601 under the drive of the slider pin 15, so that the connecting rod to be locked is locked in the meshing direction and cannot be rotated.

[0040] In a specific implementation, the locking device 16 can be fixedly installed inside the first connecting rod 1, and the slider pin 15 can be slidably installed inside the second connecting rod 2. When the pressing part 601 is pressed to a preset depth, the meshing teeth 1501 at the end of the slider pin 15 engage with the ratchet tooth surface 1601 of the locking device 16, locking the first connecting rod 1 and the second connecting rod 2 in the meshing direction, preventing the fingertip 10 from turning outward. Alternatively, the locking device 16 can be fixedly installed on the housing of the gripper body, and the slider pin 15 can be slidably installed inside the fourth connecting rod 4. When the pressing part 601 is pressed to a preset depth, the meshing teeth 1501 at the end of the slider pin 15 engage with the ratchet tooth surface 1601 of the locking device 16, locking the fourth connecting rod 4 and the housing of the gripper body in the meshing direction, preventing the fingertip 10 from turning outward.

[0041] The following description, in conjunction with the accompanying drawings, further illustrates a preferred embodiment, such as... Figure 7As shown, the sixth link 6 is mounted on the fingertip via a pin, allowing it to swing at a certain angle relative to the fingertip. The seventh link 7 is connected to the sixth link 6. One end of the eighth link 8 is mounted on the third link 3 via a pin, and the other end is connected to the seventh link 7. One end of the ninth link 9 is connected to the seventh link 7, and the other end is fitted with a rotatable and slidable slider pin 15. The slider pin 15 moves in a groove inside the second link 2, parallel to the direction of the connection between the two hinge points of the second link 2. A spring is installed between the slider pin and the ninth link 9 to ensure maximum spacing between them in the free state. A locking device 16 with ratchet teeth 1601 is installed inside the first link 1. The protruding end of the slider pin 15 is shaped like a meshing tooth 1501, which can mesh with the ratchet teeth. After meshing, the first link 1 and the second link 2 are locked in the meshing direction, preventing them from rotating relative to each other.

[0042] like Figure 8 As shown, after the gripper adaptively encloses and grasps the object, the object contacts and squeezes the gecko-like material on the fingertip, simultaneously squeezing the sixth link 6 to swing in the opposite direction. Through the linkage motion, the pointed end of the slider pin 15 inserts into the ratchet tooth gap. Under the gripping load, the pointed tooth of the slider pin 15 meshes with the ratchet tooth surface 1601. The second link 2 of the right fingertip can no longer swing counterclockwise relative to the first link 1, and the second link 2 of the left fingertip can no longer swing clockwise relative to the first link 1. The under-constrained 5-bar linkage becomes fully constrained, and the gripper can stably maintain the adaptive enclosing gripping state.

[0043] The structure of the adaptive locking mechanism linkage is as follows: Figure 10 As shown, the sixth link 6 and the eighth link 8 have fixed hinge points with triangular symbols at one end, the locking device 16 is fixedly installed, and the slider pin 15 is installed in the slide groove. When this mechanism works, it converts the oscillating motion of the sixth link 6 into the translational motion of the slider pin 15, ultimately causing the pointed teeth of the slider pin 15 to mesh with the ratchet teeth. Multiple slider pins 15 are installed side-by-side, each moving independently, with adjacent slider pins 15 staggered by a certain distance, transforming the pointed teeth of the slider pins 15 into a multi-stage tooth distribution with staggered side-by-side. Figure 11 Because the sliding pin 15 and the ratchet teeth have a stepped meshing, the number of steps depends on the number of teeth on both. However, the sliding pin 15 and the ratchet teeth adopt a many-to-one meshing form, which can further subdivide the meshing angle interval and increase the number of meshing stages.

[0044] By adopting an adaptive locking structure, when the gripper body in the adaptive covering state is subjected to a gripping load, the adaptive locking mechanism triggers the locking state, the slider pin slides to the end and contacts the locking device, locking the link to be locked, so that the drive link group becomes fully constrained, and the fingertip cannot be flipped outward, thereby enabling the gripper to stably maintain the adaptive covering gripping state.

[0045] Furthermore, the adaptive locking mechanism can also lock the included angle of the fourth link 4 on both sides, or the relative angle between the second link 2 and the third link 3, or the relative angle between the third link 3 and the fourth link 4, all of which can achieve the full constraint requirements of the gripper links and maintain the adaptive enveloping state. By changing the distribution range of the ratchet teeth, the adaptive locking mechanism can be made to work only in the adaptive enveloping grasping mode of the gripper, while the parallel grasping mode of the fingertips remains unaffected. Specifically, the locking device 16 has a ratchet tooth surface 1601 at a preset position on its exterior. The ratchet tooth surface 1601 is configured such that, in the parallel gripping state, the line connecting the first link 1 and the second link 2 is parallel to the fourth link 4, and the ratchet tooth surface 1601 is offset from the meshing teeth 1501; in the angled gripping state, there is an angle between the first link 1 and the second link 2, and the ratchet tooth surface 1601 is opposite to the meshing teeth 1501. When the gripper body is in the angled gripping state and the adaptive locking mechanism triggers the locking state, the slider pin 15, driven by external force, causes the meshing teeth 1501 to engage with the ratchet tooth surface 1601, preventing the first link 1 and the second link 2 from rotating outwards relative to each other. By changing the distribution range of the ratchet teeth, the adaptive locking mechanism can operate only in the adaptive enveloping object gripping mode of the gripper, while the fingertip parallel object gripping mode remains unaffected.

[0046] The following example illustrates how the adaptive locking mechanism locks the fourth link 4. In another preferred example, such as... Figure 11 As shown, one end of the sixth link 6 is a fixed hinge point mounted on the fingertip, and the other end is connected to the seventh link 7. One end of the eighth link 8 is a fixed hinge point mounted on the third link 3, and the other end is connected to the seventh link 7 and the ninth link 9. One end of the ninth link 9 is connected to the slider pin, which is installed in the groove of the fourth link 4. The ratchet is fixedly mounted on the housing. When the mechanism is working, the oscillating motion of the sixth link 6 is converted into the translational motion of the slider pin, which eventually causes the tips of the slider pin to mesh with the ratchet teeth, preventing the fourth link 4 from continuing to rotate counterclockwise.

[0047] In specific implementation, the adaptive locking mechanism can also adopt a similar "brake" structure, which increases the contact area between the two parts to improve the friction and thus achieve the locking effect. Specifically, the end of the slider pin 15 has a first braking surface, and the outside of the locking device 16 has a second braking surface. The first braking surface is used to fit against the second braking surface under the drive of the slider pin 15, thereby locking the connecting rod to be locked by friction.

[0048] The present invention also provides a grasping robot, the end of which is equipped with the above dual-mode gecko adhesive grippers with fingertip grasping and adaptive wrapping grasping.

[0049] This invention leverages the strong adhesion, rapid release of adhesive force, and lack of residue on the adhered surface of gecko-inspired materials. Combined with grippers, these materials offer significant advantages in industrial applications, particularly in terms of versatility and ease of operation. Current gecko-inspired grippers are mostly flexible bodies or joints, lacking the necessary gripping precision and stability for industrial applications. This invention proposes a dual-mode gecko-inspired gripper capable of both parallel fingertip gripping and adaptive wrap-around gripping. The gripper linkage is a rigid structure, while the fingertips are fitted with flexible gecko-inspired materials. This combination of rigidity and flexibility enhances the gripper's ability to protect fragile and deformable objects and enables it to handle applications requiring high precision. The gripper features both a parallel fingertip gripping mode and an adaptive wrap-around gripping mode, which can be freely switched, making it highly versatile in terms of the shape and size of the objects being gripped. The adaptive wrap-around gripping mode incorporates an adaptive locking mechanism to improve the reliability of the gripper's grasp.

[0050] In summary, the gripper provided by this invention has the following technical advantages: 1. Compared to traditional industrial grippers, by combining fingertips with flexible gecko-inspired materials, it can grasp larger objects of the same size, while requiring less clamping force, which helps to better protect fragile and easily deformable items. 2. The gripper linkage structure can flexibly switch between the fingertip parallel gripping mode and the adaptive wrapping gripping mode, thus providing greater versatility in gripping objects of different shapes and sizes; 3. The combination of rigid linkage and adaptive locking mechanism improves the reliability and accuracy of grasping, making it suitable for application scenarios with higher requirements for operational precision, such as precise alignment, placement or insertion / removal of objects after grasping them. 4. Based on the passive adhesion characteristics of gecko-inspired materials, the power system of the grippers can be simplified, eliminating the need for additional air sources or other power devices.

[0051] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0052] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A flexible biomimetic adhesive gripper, characterized in that, The device includes a pair of gripper bodies, each gripper body comprising a fingertip (10) and a drive linkage assembly. The fingertip (10) is mounted at the end of the drive linkage assembly, which is configured to drive the movement and rotation of the fingertip (10) by rotating the first linkage (1) located at the head end. Flexible gecko bionic material is installed on the grasping surface inside the fingertip (10). The gripper body includes a parallel grasping state and an angled grasping state. In the parallel grasping state, the two fingertips (10) are parallel to each other. In the angled grasping state, the two fingertips (10) are relatively outward. The material is embedded in the flexible gecko bionic material on the grasping surface inside the fingertip (10).

2. The flexible biomimetic adhesive gripper according to claim 1, characterized in that, The drive linkage group includes a first link (1), a second link (2), a third link (3), and a fourth link (4). One end of the first link (1) is connected to the drive device, the other end of the first link (1) is hinged to one end of the second link (2), the other end of the second link (2) is hinged to one end of the third link (3), the other end of the third link (3) is connected to the fingertip (10), one end of the fourth link (4) is hinged to the middle of the third link (3), and the other end of the fourth link (4) is hinged to the housing (17) of the gripper body; The first link (1) serves as a driving link, used to rotate the fingertip (10) inward and outward; Parallel gripping state: The first link (1) and the second link (2) move to the parallel limit, so that the line connecting the first link (1) and the second link (2) is parallel to the fourth link and has the same length. At this time, the two fingertips (10) are parallel to each other. Angle gripping state: The second link (2) and the third link (3) move to the angle limit position, at which point there is an outward folding angle between the two fingertips (10).

3. The flexible biomimetic adhesive gripper according to claim 2, characterized in that, An elastic covering layer is installed on the grasping surface inside the fingertip (10), and the flexible gecko bionic material is disposed on the elastic covering layer.

4. The flexible biomimetic adhesive gripper according to claim 3, characterized in that, The elastic covering layer includes a sponge or an air bladder.

5. The flexible biomimetic adhesive gripper according to claim 2, characterized in that, An adaptive locking mechanism is provided between the first link (1) and the second link (2), or an adaptive locking mechanism is provided between the fourth link (4) and the housing (17) of the gripper body; The adaptive locking mechanism is used to restrict the outward extension of the fingertip (10) after it is in place during the second grasping phase.

6. The flexible biomimetic adhesive gripper according to claim 5, characterized in that, The adaptive locking mechanism includes a locking device (16) and a sliding pin (15). The locking device (16) is fixedly installed inside the first link (1), and the slider pin (15) is slidably installed inside the second link (2). The slider pin (15) is configured such that when the fingertip (10) is in the inward position, the slider pin (15) slides to contact the locking device (16), so that the first link (1) and the second link (2) are locked, and the fingertip (10) cannot be flipped outward. Alternatively, the locking device (16) is fixedly installed on the housing (17) of the gripper body, and the slider pin (15) is slidably installed inside the fourth link (4). The slider pin (15) is configured such that when the fingertip (10) is in the inward position, the slider pin (15) slides to contact the locking device (16), so that the first link (1) and the second link (2) are locked, and the fingertip (10) cannot be flipped outward.

7. The flexible biomimetic adhesive gripper according to claim 6, characterized in that, The end of the slider pin (15) has a meshing tooth (1501), and the outside of the locking device (16) has a ratchet tooth surface (1601). The meshing teeth (1501) are used to mesh with the ratchet teeth (1601) under the drive of the slider pin (15), so that the connecting rod to be locked is locked in the meshing direction and cannot be rotated.

8. The flexible biomimetic adhesive gripper according to claim 6, characterized in that, The end of the slider pin (15) has a first braking surface, and the outside of the locking device (16) has a second braking surface; The first braking surface is used to fit against the second braking surface under the action of the slider pin (15), thereby locking the connecting rod to be locked by friction.

9. A robot, characterized in that, The flexible biomimetic adhesive gripper described in any one of claims 1-8 is used.

10. The robot according to claim 9, characterized in that, The robot includes one or more robotic arms, the ends of which are fitted with flexible biomimetic adhesive grippers as described in any one of claims 1-8.

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