3D Printable Gradient Lattice Design for Multi-Stiffness Robotic Fingers

TL;DR

This paper introduces a 3D printable lattice design for robotic fingers that mimics human multi-stiffness structures, enabling fine-tuned stiffness control and integrated manufacturing for improved dexterity and grasping capabilities.

Contribution

It proposes a novel lattice-based approach for multi-stiffness robotic fingers that can be 3D printed in a single process, reducing assembly complexity.

Findings

Successfully designed a human-like robotic finger with variable stiffness

Demonstrated effective pick and place tasks with the soft gripper

Enabled high granularity in stiffness tuning through lattice parameterization

Abstract

Human fingers achieve exceptional dexterity and adaptability by combining structures with varying stiffness levels, from soft tissues (low) to tendons and cartilage (medium) to bones (high). This paper explores developing a robotic finger with similar multi-stiffness characteristics. Specifically, we propose using a lattice configuration, parameterized by voxel size and unit cell geometry, to optimize and achieve fine-tuned stiffness properties with high granularity. A significant advantage of this approach is the feasibility of 3D printing the designs in a single process, eliminating the need for manual assembly of elements with differing stiffness. Based on this method, we present a novel, human-like finger, and a soft gripper. We integrate the latter with a rigid manipulator and demonstrate the effectiveness in pick and place tasks.