Bendable-Finger Gripper With Switchable Bending for Flat Objects

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing grippers struggle to reliably grip both convex and flat-walled objects without requiring additional active drives, and they often bend when attempting to grasp flat-walled objects.

Innovation Solution

A gripper design featuring a kinematic chain of adjustable finger links with a traction means and a switching mechanism that allows the gripper to close without bending when gripping flat-walled objects, using a switching means to block the traction means and prevent bending during closure.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If the gripper finger is designed to be bendable to grip convex objects, then the ability to grip convex objects is improved, but the finger bends when attempting to grasp flat-walled objects

Engineering Contradiction:
Improveability to grip convex objectsVSAvoidfinger bending on flat objects
Core Design Contradiction:
Adaptability or versatilityVSShape

Solution Approach 1:

The gripper finger is designed with a kinematic chain of finger links that can dynamically change their configuration. The switching means allows the system to transition between a bendable state (for convex objects) and a rigid state (for flat-walled objects), making the finger's mechanical properties adaptive rather than fixed

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes the mechanical parameter of finger rigidity by introducing a switching means that can alter the kinematic chain's degree of freedom. When the switching means is in the first position, the finger links can bend; when in the second position, the finger is constrained to remain straight, thus changing the rigidity parameter based on the object type

Inventive Principle:
Principle #35Parameter changes

2Adaptability or versatility

If a switching means is added to prevent finger bending, then the ability to grip flat-walled objects is improved, but the device complexity increases

Engineering Contradiction:
Improveability to grip flat-walled objectsVSAvoidgripper structure complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The switching means serves multiple functions: it controls the bending capability of the finger, maintains the kinematic chain's integrity, and enables the gripper to adapt to different object types. This single component performs what would otherwise require multiple separate mechanisms

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The switching means is integrated into the existing gripper structure and utilizes the same actuation system (traction means) already present for finger movement. The kinematic chain's own components are used to enable/disable bending, rather than requiring an entirely separate control system

Inventive Principle:
Principle #25Self-service

Data Source

PatentEP4452574B1Gripper with bendable fingers and switching means
Publication Date: 2025.09.03 KUKA DEUT GMBH
  • EP4452574B1 patent drawingFigure 1
  • EP4452574B1 patent drawingFigure 2
  • EP4452574B1 patent drawingFigure 3~4

AI summary

The invention relates to a gripper (1) comprising a main gripper body (3) and at least two gripper fingers (2.1, 2.2), of which at least one is moveably mounted on the main gripper body (3). The gripper (1) comprises a switching means (24) which can be switched between a first switch position and a second switch position, and which completely releases the pulling means (8.1, 8.2) in the first switch position, such that, by pulling on the pulling means (8.1, 8.2), the gripper finger (2.1, 2.2) that is moveably mounted on the main gripper body (3) is both pulled into a closed position and the kinematic chain of the finger element (7) of the moveably mounted gripper finger (2.1, 2.2) is bent, and which blocks a section of the pulling means (8.1, 8.2) running along the kinematic chain of the finger element (7) of the moveably mounted gripper finger (2.1, 2.2) in the second switch position, such that, by pulling on the pulling means (8.1, 8.2), the gripper finger (2.1, 2.2) moveably mounted on the main gripper body (3) is only pulled into a closed position, without the kinematic chain of the finger element (7) of the moveably mounted gripper finger (2.1, 2.2) being bent.