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.
@article{arxiv.2501.03763,
title = {3D Printable Gradient Lattice Design for Multi-Stiffness Robotic Fingers},
author = {Siebe J. Schouten and Tomas Steenman and Rens File and Merlijn Den Hartog and Aimee Sakes and Cosimo Della Santina and Kirsten Lussenburg and Ebrahim Shahabi},
journal= {arXiv preprint arXiv:2501.03763},
year = {2025}
}