Linkage mechanism with knuckle fingertip co-grasping function

Abstract

The utility model provides a kind of connecting rod mechanism with knuckle fingertip common grasping function, including fourth connecting rod and fingertip, fourth connecting rod is as knuckle connecting rod, inside with knuckle gripping portion;The proximal end of fingertip is rotatably connected with the distal end of fourth connecting rod, and fingertip is hinged with the distal end of the driving connecting rod group of clamp jaw, the proximal end of fourth connecting rod is hinged with the shell of clamp jaw body;First grasping stage: fingertip rotates to abduct, the included angle between fingertip and fourth connecting rod is first included angle at this time;Second grasping stage: fingertip rotates to inner buckle, the included angle between fingertip and fourth connecting rod is second included angle at this time, second included angle is less than first included angle.The utility model installs fingertip in the most distal end of fourth connecting rod, gripping portion in fourth connecting rod inside can contact object surface first, fingertip can contact object surface after driving, form the inner buckle state of sticking object, it is favorable to promote the sticking degree of grasping surface and object surface, to enhance friction, improve grasping performance.

Description

Technical Field

[0001] This utility model relates to the field of robotics technology, specifically to a linkage mechanism with a joint grasping function of knuckles and fingertips. Background Technology

[0002] For robot grippers driven by linkage mechanisms, when grippers grasp large objects, the gripping part is usually arranged in a "V" shape. When grasping large objects, the gripping load capacity and stability are poor due to the lack of the fingertip action at the far end of the gripper. 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, with its "V-shaped" arrangement of the side links fitted with gecko-inspired materials, lacks the distal fingertip action of the gripper when grasping large objects, resulting in poor gripping load capacity and stability. Therefore, there is an urgent need to introduce a linkage mechanism with a reasonable fingertip gripping position into the robot gripper, which can give full play to the role of the distal fingertip of the gripper and improve the adhesion between the gripping surface and the object surface. Utility Model Content

[0003] In view of the deficiencies in the existing technology, the purpose of this utility model is to provide a linkage mechanism with joint and fingertip grasping function.

[0004] The linkage mechanism with joint grasping function of knuckles and fingertips provided by this utility model includes a fourth link and a fingertip, wherein the fourth link serves as a knuckle link and has a knuckle grasping part on its inner side. The proximal end of the fingertip is rotatably connected to the distal end of the fourth link, and the fingertip is hinged to the distal end of the drive link assembly of the gripper, for rotating around the distal end of the fourth link under the drive of the drive link assembly. The proximal end of the fourth link is hinged to the housing of the gripper body. First grasping stage: The fingertip rotates to an outward state under the drive of the drive linkage group, and the angle between the fingertip and the fourth linkage is the first angle at this time; Second grasping stage: The fingertip rotates to an inward-curving state under the drive of the drive linkage group. At this time, the angle between the fingertip and the fourth link is the second angle, which is smaller than the first angle.

[0005] Preferably, the inner side of the fourth link protrudes upward to form a knuckle gripping part.

[0006] Preferably, both the knuckle gripping portion and the gripping surface of the fingertip are provided with flexible material.

[0007] Preferably, when the fingertip is in the inward-curling state, the gripping surface of the fingertip and the gripping surface of the knuckle gripping part form a V-shape.

[0008] Preferably, there is an angle between the gripping surface at the top of the knuckle gripping part and the length direction of the fourth link.

[0009] Preferably, the knuckle gripping part and the fourth link are separately configured, and the knuckle gripping part is fixedly installed on the inner side of the fourth link by a fastener.

[0010] Preferably, an elastic covering layer is installed on both the gripping surface on the inner side of the fingertip and the gripping part of the knuckle.

[0011] Preferably, the elastic covering layer comprises a sponge or an air bladder.

[0012] Preferably, the cross-section of the knuckle gripping part is wedge-shaped, and the tip of the wedge points towards the proximal end of the fourth link.

[0013] Preferably, the distal end of the fourth link is hinged to the distal end of the drive link assembly, and is used to rotate around the proximal end of the fourth link under the drive of the drive link assembly.

[0014] Compared with the prior art, the present invention has the following beneficial effects: This invention involves mounting the fingertip at the farthest end of the fourth link. The gripping part on the inner side of the fourth link can contact the object surface first, and the fingertip can then contact the object surface under drive, forming an inwardly hooked state that adheres to the object. This state helps to increase the contact area between the fingertip and the object, improve the adhesion between the gripping surface and the object surface, thereby enhancing the friction between the two and ultimately improving the gripping performance. Attached Figure Description

[0015] Other features, objects, and advantages of this 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 gripper grasping an object in a parallel gripping state in this utility model; Figure 3 This is a schematic diagram illustrating the working principle of the gripper grasping an object in an angled gripping state in this utility model; Figure 4 This is a schematic diagram illustrating the working principle of the gripper switching to the parallel gripping state in this utility model; Figure 5 This is a schematic diagram illustrating the working principle of the gripper switching to the angle gripping state in this utility model; Figure 6 This is a schematic diagram of the assembly of the state switching mechanism and the gripper body in this utility model. Figure 7 This is a schematic diagram of the assembly of the adaptive locking mechanism and the gripper body in this utility model. 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 utility model; Figure 10 This is a schematic diagram of the locking principle of the adaptive locking mechanism in this utility model; Figure 11 This is a schematic diagram of the assembly of the adaptive locking mechanism and the gripper body in this utility model. Figure 2 .

[0016] The diagram shows: Detailed Implementation

[0017] 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 present 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.

[0018] This utility model discloses a linkage mechanism with joint gripping function of knuckles and fingertips. By installing the fingertips at the farthest end of the fourth linkage, the gripping part on the inner side of the fourth linkage can first contact the object surface, and the fingertips can then contact the object surface under drive, forming an inwardly hooked state that fits the object. This state helps to increase the contact area between the fingertips and the object, improve the fit between the gripping surface and the object surface, thereby enhancing the friction between the two and ultimately improving the gripping performance.

[0019] Based on the linkage mechanism with joint grasping function of the knuckles and fingertips mentioned above, this utility model also discloses a gripper. The gripper disclosed in this utility model has flexible gecko-inspired material installed on the fingertips, which has the advantages of other gecko adhesive grippers. The gripper linkage can switch the arrangement form during the movement to realize two grasping modes: (1) parallel grasping mode of fingertips; (2) adaptive wrapping grasping mode of fingertips and knuckle linkage working together.

[0020] 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.

[0021] 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.

[0022] 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.

[0023] 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.

[0024] 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.

[0025] 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.

[0026] 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.

[0027] 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.

[0028] 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.

[0029] 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.

[0030] 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.

[0031] 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.

[0032] 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.

[0033] 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.

[0034] 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.

[0035] 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.

[0036] 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.

[0037] 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.

[0038] 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.

[0039] 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.

[0040] 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.

[0041] 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.

[0042] 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.

[0043] 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.

[0044] This utility model also provides a grasping robot, the end of which is equipped with the above dual-mode gecko adhesive gripper with fingertip grasping and adaptive wrapping grasping.

[0045] This invention leverages the strong adhesion, rapid release of adhesive force, and residue-free adhesion of gecko-inspired materials. Combined with a gripper for industrial applications, it offers significant advantages in versatility and ease of operation. Current gecko-inspired grippers are mostly flexible bodies or joints, lacking precision and stability in 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 parallel fingertip gripping and adaptive wrap-around gripping modes, which can be freely switched, making it more versatile in terms of object shape and size. The adaptive wrap-around gripping mode incorporates an adaptive locking mechanism to improve the gripper's reliability.

[0046] In summary, the gripper provided by this utility model 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 biomimetic materials, the power system of the gripper can be simplified, eliminating the need for an additional air source or other power device. In the description of this application, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and 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, and therefore should not be construed as a limitation of this application.

[0047] The specific embodiments of this utility model have been described above. It should be understood that this utility model 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 substantive content of this utility model. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A linkage mechanism with joint grasping function of knuckles and fingertips, characterized in that, It includes a fourth link (4) and a fingertip (10), wherein the fourth link (4) is a knuckle link and has a knuckle gripping part on the inner side; The proximal end of the fingertip (10) is rotatably connected to the distal end of the fourth link (4), and the fingertip (10) is hinged to the distal end of the drive link assembly of the gripper, for rotating around the distal end of the fourth link (4) under the drive of the drive link assembly. The proximal end of the fourth link (4) is hinged to the housing (17) of the gripper body. First grasping stage: The fingertip (10) rotates to the outward state under the drive of the drive linkage group. At this time, the angle between the fingertip (10) and the fourth link (4) is the first angle. Second grasping stage: The fingertip (10) rotates to the inward state under the drive of the drive linkage group. At this time, the angle between the fingertip (10) and the fourth link (4) is the second angle, which is smaller than the first angle.

2. The linkage mechanism with joint grasping function of knuckles and fingertips according to claim 1, characterized in that, The inner side of the fourth link (4) protrudes upward to form a knuckle gripping part.

3. The linkage mechanism with joint grasping function of knuckles and fingertips according to claim 1, characterized in that, Flexible material is provided on the gripping surfaces of the knuckle gripping part and the fingertip (10).

4. The linkage mechanism with joint grasping function of knuckles and fingertips according to claim 1, characterized in that, When the fingertip (10) is in the inward-curling state, the gripping surface of the fingertip (10) and the gripping surface of the knuckle gripping part form a V-shape.

5. The linkage mechanism with joint grasping function of knuckles and fingertips according to claim 2, characterized in that, There is an angle between the gripping surface at the top of the knuckle gripping part and the length direction of the fourth link (4).

6. The linkage mechanism with joint grasping function of knuckles and fingertips according to claim 2, characterized in that, The knuckle gripping part and the fourth link (4) are separately arranged, and the knuckle gripping part is fixedly installed on the inside of the fourth link (4) by a fastener.

7. The linkage mechanism with joint grasping function of knuckles and fingertips according to claim 1, characterized in that, Both the gripping surface on the inner side of the fingertip (10) and the gripping part of the knuckle are equipped with an elastic covering layer.

8. The linkage mechanism with joint grasping function of knuckles and fingertips according to claim 7, characterized in that, The elastic covering layer includes a sponge or an air bladder.

9. The linkage mechanism with joint grasping function of knuckles and fingertips according to claim 5, characterized in that, The cross-section of the knuckle gripping part is wedge-shaped, and the tip of the wedge points towards the proximal end of the fourth link (4).

10. The linkage mechanism with joint grasping function of knuckles and fingertips according to claim 1, characterized in that, The distal end of the fourth link (4) is hinged to the distal end of the drive link assembly, and is used to rotate around the proximal end of the fourth link (4) under the drive of the drive link assembly.

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