A Novel Reconfigurable Dexterous Hand Based on Triple-Symmetric Bricard Parallel Mechanism
Chunxu Tian, Zhichao Huang, Hongzeng Li, Bo Wang, Jinghao Jia, Yirui Sun, Dan Zhang
AI summary
Problem
Conventional dexterous hands struggle with adaptability to varying object geometries due to fixed palm structures, while existing reconfigurable designs often neglect the critical role of palm posture and shape during grasping.
Approach
The authors synthesize a topological graph to design a triple-symmetric Bricard parallel mechanism for the palm, followed by rigorous kinematic analysis using screw theory and closed-loop constraints, and performance evaluation via workspace, stiffness, and transmission efficiency metrics.
Key results
- Topological synthesis identifies a non-isomorphic triple-symmetric configuration balancing complexity and stiffness.
- Forward and inverse kinematic models are derived, ensuring unique motion coordination without bifurcation.
- Performance analysis confirms positive stiffness throughout the workspace and high motion/force transmission efficiency.
- Prototype testing demonstrates stable, efficient grasping across a wide range of object shapes and sizes.
Why it matters
This design provides a robust, adaptable solution for advanced robotic manipulation in industrial and complex environments where precision and versatility are critical.
Abstract
This paper introduces a novel design for a robotic hand based on parallel mechanisms. The proposed hand uses a triple-symmetric Bricard linkage as its reconfigurable palm, enhancing adaptability to objects of varying shapes and sizes. Through topological and dimensional synthesis, the mechanism achieves a well-balanced degree of freedom and link configura- tion suitable for reconfigurable palm motion, balancing dexter- ity, stability, and load capacity. Furthermore, kinematic analysis is performed using screw theory and closed-loop constraints, and performance is evaluated based on workspace, stiffness, and motion/force transmission efficiency. Finally, a prototype is developed and tested through a series of grasping experiments, demonstrating the ability to perform stable and efficient ma- nipulation across a wide range of objects. The results validate the effectiveness of the design in improving grasping versatility and operational precision, offering a promising solution for advanced robotic manipulation tasks.