Adaptive Variable Stiffness Particle Phalange for Robust and Durable Robotic Grasping.

Area of Science:

• Robotics
• Materials Science
• Mechanical Engineering

Background:

• Soft grippers offer compliance and safety for human-robot interaction but lack robustness and durability, limiting their application.
• Existing soft robotic hands struggle with heavy or sharp objects due to material fragility and low structural stiffness.
• Enhancing grasping performance requires addressing the trade-off between inherent compliance and loading capacity.

Purpose of the Study:

• To introduce a novel variable stiffness particle phalange (VSPP) for soft robotic hands.
• To demonstrate VSPP's ability to achieve variable stiffness passively through particle jamming.
• To enhance the robustness, durability, and safety of soft robotic grippers.

Main Methods:

• Development of a variable stiffness particle phalange (VSPP) utilizing passive particle jamming.
• Integration of VSPP with existing actuators (soft or rigid) to create robotic hands.
• Fabrication and testing of a prototype VSPP-based robotic hand (VSPP-3) with pneumatic joints.

Main Results:

• The VSPP exhibits variable stiffness without dedicated actuation, relying on environmental interaction forces.
• A prototype robotic hand demonstrated reliable grasping even when subjected to sharp objects like needles and cacti.
• The VSPP-based gripper maintained performance underwater and ensured safety in human-robot interaction.

Conclusions:

• The VSPP design offers a promising solution for creating robust and durable soft robotic hands.
• Passive particle jamming is an effective mechanism for achieving variable stiffness in soft robotic phalanges.
• The VSPP technology opens new possibilities for soft robotics in harsh environments and human-centered applications.