Adaptive Robot Gripper With Six-Bar Linkage for Cylindrical Grasping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional grippers for robot hands face challenges in stably grasping objects of various shapes and sizes, particularly cylindrical objects, due to limitations in link length and gripping force, which often require adjustments that compromise gripping stroke allowance and increase processing costs.
Innovation Solution
A gripper design incorporating a finger unit with multiple links and elastic members, allowing for selective or sequential performance of pinch and encompassing grips through a six-bar link structure and torsion or coil springs, enabling adaptive grasping of diverse objects without compromising gripping stroke allowance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the length of link is adjusted to broaden the range of object size, then the adaptability is improved, but the gripping stroke allowance decreases and processing costs increase
Solution Approach 1:
The finger is divided into multiple links (first link, second link, third link, fourth link) that can move relative to each other. This segmentation allows the finger to change its effective length and configuration to adapt to different object sizes without requiring adjustment of the overall link length, thereby maintaining gripping stroke allowance while improving adaptability.
Solution Approach 2:
The gripper employs a dynamic link mechanism where the relative positions and orientations of the links can change during operation. This dynamic configuration allows the finger to adapt its shape and length to match different object geometries, achieving versatile grasping without compromising the gripping stroke.
2Adaptability or versatility
If the length of link is adjusted to grasp cylindrical objects, then the adaptability is improved, but the gripping force decreases
Solution Approach 1:
The segmented link structure allows the finger to conform to cylindrical surfaces while maintaining structural integrity. The multiple links can articulate to match the curvature of cylindrical objects, distributing the gripping force across multiple contact points and preserving sufficient gripping force while achieving adaptability.
Solution Approach 2:
The invention combines pinch grip and encompassing grip capabilities within a single unified mechanism. By merging these two grip modes into one system that can switch between them, the gripper achieves versatile grasping of cylindrical objects while maintaining adequate gripping force through the coordinated action of all links.
3Device complexity
If the finger structure is simplified for pinch grip, then the device complexity is reduced, but the adaptability to various shapes decreases
Solution Approach 1:
Rather than simplifying the structure to a single rigid element, the invention uses segmentation into multiple links that can move relative to each other. This segmentation creates apparent complexity but actually provides adaptability through the controlled movement between links, allowing the finger to conform to various object shapes while maintaining a relatively compact and efficient structure.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The gripper stably grasps objects of various shapes and sizes with high gripping force, maintaining the gripping stroke allowance, and can adapt to different grip modes, effectively addressing the limitations of conventional grippers.
Implementation Method 1
a first elastic member provided between the first link and the second link or between the second link and the gripping member may be biased in the direction of gripping. In addition, a second elastic member provided between the third link and the fourth link or between the fourth link and the gripping member may be biased in the opposite direction of gripping.
Data Source
AI summary
Disclosed is a gripper for robot hand capable of adaptive grasp, including a finger unit having one or more finger which includes a first link of which one end is rotatably fixed to a casing; a second link of which one end is jointly coupled with the other end of the first link; a third link of which one end is rotatably fixed to the casing, which is operated by receiving a driving force from the outside; a fourth link of which one end is jointly coupled with the other end of the third link; and a gripping member jointly coupled with the other end of the second link and the other end of the fourth link.