CN-121989283-A - Self-adaptive rigid-flexible coupling handle based on composite bionic telescopic joint

CN121989283ACN 121989283 ACN121989283 ACN 121989283ACN-121989283-A

Abstract

The invention relates to a self-adaptive rigid-flexible coupling gripper based on a composite bionic telescopic joint, which comprises two groups of bionic grippers, modularized self-adaptive gripping units and a driving and adjusting mechanism, wherein the two groups of bionic grippers, the modularized self-adaptive gripping units and the driving and adjusting mechanism are symmetrically arranged on the left and right sides, the bionic grippers comprise rigid supporting members, flexible drivers, a plurality of rigid sliding block units and a multi-stage scissor-fork connecting rod mechanism, the flexible drivers can drive the rigid sliding block units to axially stretch and retract, the multi-stage scissor-fork connecting rod mechanism ensures that all the rigid sliding block units synchronously move equidistantly, the modularized self-adaptive gripping units comprise rigid side arms, contact fingers and flexible contact belts, the rigid side arms are hinged with the rigid sliding block units and are connected through springs, the contact fingers are arranged at the free ends of the rigid side arms through universal spherical hinges, the flexible contact belts are tensioned between the rigid side arms on the two sides and the corresponding rigid sliding block units, and the driving and adjusting mechanism is used for driving the flexible drivers to stretch and the two groups of bionic grippers to adjust the distance. The invention realizes large-stroke expansion and self-adaptive grabbing through the rigid-flexible coupling structure, and has stable structure and strong adaptability.

Inventors

JIANG QUANSHENG
LI ZHIKE
SHEN YEHU
WU SHILEI
ZHU QIXIN

Assignees

苏州科技大学

Dates

Publication Date: 20260508
Application Date: 20260408

Claims (10)

1. The self-adaptive rigid-flexible coupling gripper based on the composite bionic telescopic joint is characterized by comprising two groups of bionic grippers, a modularized self-adaptive gripping unit and a driving and adjusting mechanism which are symmetrically arranged left and right, The bionic gripper comprises a rigid supporting member, a flexible driver, a plurality of rigid sliding block units and a multi-stage scissor link mechanism, wherein the upper end of the flexible driver is fixed on the upper part of the rigid supporting member, the lower end of the flexible driver is fixedly connected with the uppermost rigid sliding block unit, and the lowermost rigid sliding block unit is fixed on the bottom of the rigid supporting member; The modularized self-adaptive grabbing unit comprises rigid side arms, contact fingers and flexible contact belts which are oppositely arranged, wherein one ends of the rigid side arms are hinged with the rigid sliding block units, and the free ends of the rigid side arms are connected with the corresponding rigid sliding block units through springs; the driving and adjusting mechanism is used for driving the flexible driver to realize telescopic action and adjusting the distance between the two groups of bionic grippers.
2. The adaptive rigid-flexible coupling gripper based on the composite biomimetic telescopic joint of claim 1, wherein the rigid support member comprises a top base, a bottom base, and a rigid support plate, the rigid support plate being vertically connected between the top base and the bottom base.
3. The adaptive rigid-flexible coupling gripper based on the composite bionic telescopic joint according to claim 1, wherein the flexible driver is a pneumatic flexible bellows.
4. The self-adaptive rigid-flexible coupling handle based on the composite bionic telescopic joint according to claim 3, wherein two ends of the pneumatic flexible corrugated pipe are rigidly and fixedly connected with corresponding components through locking rings respectively, and sealing gaskets are arranged at the joints.
5. The self-adaptive rigid-flexible coupling gripper based on the composite bionic telescopic joint according to claim 1, wherein the rigid sliding block units are uniformly distributed along the axial direction, a group of multistage scissor linkage mechanisms are hinged between every two adjacent rigid sliding block units, and each group of multistage scissor linkage mechanisms consists of two cross-hinged links.
6. The self-adaptive rigid-flexible coupling gripper based on the composite bionic telescopic joint according to claim 1, wherein the modularized self-adaptive gripping units are in one-to-one correspondence with the rigid sliding block units, and a group of modularized self-adaptive gripping units are installed on each rigid sliding block unit.
7. The adaptive rigid-flexible coupling gripper based on the composite bionic telescopic joint according to claim 1, wherein the flexible contact strip is made of an elastic silica gel material with a shore hardness of 30A.
8. The self-adaptive rigid-flexible coupling gripper based on the composite bionic telescopic joint according to claim 1, wherein the driving adjusting mechanism comprises a pneumatic driving unit and a motor driving unit, the pneumatic driving unit is connected with the flexible driver and used for driving the flexible driver to realize axial telescopic motion, and the motor driving unit is connected with the two groups of bionic grippers and used for adjusting the distance between the two groups of bionic grippers.
9. The self-adaptive rigid-flexible coupling handle based on the composite bionic telescopic joint according to claim 8, wherein the pneumatic driving unit at least comprises an air compressor, a pressure regulating valve and an air pipe, the air compressor is connected with the flexible driver through the air pipe, and the pressure regulating valve is arranged on the air pipe and used for regulating air pressure input into the flexible driver.
10. The adaptive rigid-flexible coupling gripper based on the composite bionic telescopic joint according to claim 8, wherein the motor driving unit comprises a stepping motor, a positive and negative screw assembly and sliding blocks, the two groups of bionic grippers are fixedly connected with the two sliding blocks of the positive and negative screw assembly respectively, and the stepping motor is used for driving the positive and negative screw assembly to rotate so as to adjust the distance between the two groups of bionic grippers.

Description

Self-adaptive rigid-flexible coupling handle based on composite bionic telescopic joint Technical Field The invention relates to the technical field of robot end effectors, in particular to a self-adaptive rigid-flexible coupling gripper based on a composite bionic telescopic joint. Background Currently, with the advancement of industry wave and the proliferation of modern agriculture fine operation demands, the robot operation environment gradually evolves from a structured, single task scene to an unstructured, dynamically changeable complex environment. In the front-edge fields of nondestructive picking of fruits and vegetables, collection of deep sea biological samples, rehabilitation medical assistance, sorting and assembling of complex special-shaped workpieces and the like, an end effector is used as a terminal medium for interaction between a robot system and the physical world, and the environmental adaptability and the operation stability of the end effector directly influence the upper limit of the efficiency of the system. For a long time, the traditional gripper based on the rigid connecting rod and the precise transmission mechanism establishes a dominant position in standardized industrial scenes such as automobile manufacturing, electronic assembly and the like by virtue of a complete kinematic theory basis, hard structural rigidity and excellent load capacity. However, the rigid gripper has the characteristics of being essentially hard-contacted, so that the rigid gripper is not attractive when facing a target object with irregular shape, fragile material (such as strawberries and jellyfish) or large size span, and in order to avoid mechanical damage to an operation object, high-cost multidimensional force/touch sensing is often required to be introduced and complex force-position mixed control strategies are matched, so that the software and hardware cost of the system is greatly increased, and the popularization and application of the rigid gripper in a universal gripping task are severely limited. In this context, the rise of soft robotics provides a completely new perspective for solving the above-mentioned problems. The gripper usually abandons the traditional rigid joint, adopts materials with super-elastic characteristics such as silicon rubber, dielectric elastomer or shape memory alloy, and utilizes nonlinear large deformation of the materials to realize passive self-adaptive enveloping of a target object, so that better man-machine interaction safety and morphological adaptation capability are realized on the premise of not needing a complex control algorithm. The current academic world has emerged a great number of innovative designs of bionic soft grippers based on the principles of pneumatic networks, line driving, fluid elastomer driving and the like. Although soft grips have natural advantages in terms of "compliant interactions," their inherent drawbacks of "low stiffness" and "fixed range" are increasingly exposed to the complex and varied gripping demands of actual work scenarios. Specifically, the inherent low elastic modulus of the fully soft structure causes that buckling instability or unexpected torsional deformation of the structure is very easy to occur when the fully soft structure grabs a large-mass object or resists external dynamic disturbance, and the pose precision and the load stability of the operation process are difficult to ensure. More troublesome is that the existing soft grippers mostly rely on bending deformation of fingers to construct a grabbing envelope, the finger spacing and the effective working space of the existing soft grippers are limited at the beginning of design, so that a single gripper is difficult to simultaneously consider objects with huge size differences, namely, small-size grippers cannot envelope large-diameter objects, and the large-size grippers are heavy and have low contact force transmission efficiency when grabbing tiny targets. The lack of scale adaptability becomes a great obstacle for the application of the software robot to the generalization. In view of the bottleneck, researchers have developed an improved study on the stiffness varying mechanism and the adaptive structure of the gripper. In terms of stiffness enhancement, variable stiffness techniques based on particle blocking, lamellar blocking, and low melting point alloy phase transformation are widely introduced into the design of soft drivers. However, examining these variable stiffness strategies, it is not difficult to find that the design focus is mainly on the "force" intensification, and often requires the integration of heavy vacuum pumps or slow-responding heating devices, resulting in a bulky system, increased energy consumption, and does not fundamentally address the geometric constraint problem of limited gripping "range". In terms of adaptive structural optimization, passive adaptive grippers based on fin effects are attracting a great deal of attent