A Variable Stiffness Gripper with Reconfigurable Finger Joint for Versatile Manipulations

Area of Science:

• Robotics
• Mechanical Engineering
• Materials Science

Background:

• Traditional grippers often lack versatility, being either rigid (high precision, low adaptability) or soft (high adaptability, low precision).
• A need exists for robotic end-effectors that combine the strengths of both rigid and soft grippers for complex manipulation tasks.

Purpose of the Study:

• To design and develop a reconfigurable dexterous gripper capable of switching between rigid and flexible states.
• To enable tunable stiffness in the flexible state for adapting to various object properties.
• To investigate the performance and applicability of this novel gripper design in collaborative robotics.

Main Methods:

• A novel reconfigurable mechanism with a slider-based state-switching system for fingertip joints.
• Integration of servo actuation for rigid state and spring-supported, cable-driven motor actuation for flexible state with tunable stiffness.
• Analysis of kinematic characteristics and experimental testing of the gripper's performance across different configurations.

Main Results:

• The gripper successfully demonstrated switching between rigid and flexible operational states.
• Tunable stiffness in the flexible state was achieved, allowing adaptation to different objects.
• Experimental validation confirmed the gripper's practicability and versatility for tasks requiring both precision and adaptability.

Conclusions:

• The developed reconfigurable dexterous gripper offers a unique combination of precision, load capacity, adaptability, and safety.
• The stiffness-tunable mechanism enhances versatility for grasping and manipulation of objects with varying shapes and stiffness.
• This design shows significant potential for applications in rigid-flexible collaborative works and advanced robotic manipulation.