Multi-joint Hand Mechanism with Single Actuator for Versatile Gripping
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Solution Overview
Problem
Conventional robot hand mechanisms are complex, making them difficult to produce and control, and they lack the durability and maintainability required for industrial applications, especially in factories, where they need to perform a variety of gripping actions.
Innovation Solution
A hand mechanism with two multi-joint fingers and one single-joint finger, driven by a single actuator, allowing for two modes of gripping action: pinching and enfolding, which simplifies the structure while maintaining stability and versatility.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a conventional hand mechanism with multiple actuators is used to perform various gripping actions, then the versatility of gripping is improved, but the device complexity increases and durability decreases
Solution Approach 1:
The patent implements a hand mechanism where a single actuator controls multiple fingers to perform various gripping actions including pinching, enveloping, and rolling. The mechanism achieves multi-functionality through coordinated movement of fingers with different degrees of freedom, allowing one actuator to replace what would traditionally require multiple actuators, thus reducing complexity while maintaining versatility
Solution Approach 2:
The hand mechanism employs dynamic control where fingers can rotate at multiple joints with varying degrees of freedom. The mechanism adapts its configuration based on the gripping task, with some joints locked and others free to move, enabling the same mechanical structure to perform different gripping functions dynamically without requiring separate mechanisms for each function
2Adaptability or versatility
If a conventional hand mechanism with multiple actuators is used to perform various gripping actions, then the gripping capability is improved, but the ease of manufacture and maintainability worsen
Solution Approach 1:
By designing a mechanism where one actuator controls multiple fingers through a system of linkages and joints, the patent reduces the total number of components that need to be manufactured and assembled. This universal control approach simplifies production while maintaining the ability to perform multiple gripping functions
Solution Approach 2:
The patent combines multiple finger control functions into a single actuator system, merging what would traditionally be separate actuation systems into one integrated mechanism. This reduction in component count directly improves ease of manufacture and assembly while maintaining full gripping capability
3Adaptability or versatility
If a conventional hand mechanism with multiple actuators is used, then the variety of gripping actions is improved, but the controllability and reliability worsen
Solution Approach 1:
The hand mechanism incorporates sensors that detect contact forces and positions, providing feedback to the control system. This feedback allows the single actuator to dynamically adjust the positioning and force applied by each finger, ensuring reliable and controllable gripping actions despite the reduced number of actuators
Solution Approach 2:
The mechanism dynamically adjusts the degrees of freedom of different joints based on the gripping task and feedback from sensors. This dynamic adaptation allows the system to maintain high reliability by optimizing the configuration of fingers for each specific gripping action, preventing over-constraint or instability
Data Source
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AI summary
A hand mechanism comprises a first multi-joint finger and a second multi-joint finger as well as a single-joint finger which is rotatable about a center of a predetermined connecting portion together with the first multi-joint finger and the second multi-joint finger, wherein the mechanism executes a first mode in which the respective entire fingers of the first multi-joint finger and the second multi-joint finger are rotated in an identical direction by the aid of a connecting portion with respect to an attachment member when a driving force is applied from a driving actuator and a second mode in which a finger section other than a first predetermined finger section included in the first multi-joint finger is rotated with respect to the first predetermined finger section and a finger section other than a second predetermined finger section included in the second multi-joint finger is rotated with respect to the second predetermined finger section, when the rotation of the first predetermined finger section included in the first multi-joint finger and the rotation of the second predetermined finger section included in the second multi-joint finger are inhibited in the first mode. Accordingly, it is possible to realize a variety of gripping actions and it is also possible to realize preferred durability or tolerance and maintainability by simplifying the structure.