Fast 3D Modeling of Anthropomorphic Robotic Hands Based on A Multi-layer Deformable Design

TL;DR

This paper introduces a rapid, low-cost, multi-layer 3D printable anthropomorphic robotic hand design that models skin, tissues, and bones, improving flexibility, customization, and resemblance to human hands.

Contribution

It presents a novel multi-layer design approach using 3D scanning and template matching, enabling fast, customizable, and deformable robotic hands with a low-cost underactuated system.

Findings

Outperforms previous designs in grasping 33 object types

Enables fast and low-cost production of anthropomorphic hands

Provides adjustable deformability for tissue layers

Abstract

Current anthropomorphic robotic hands mainly focus on improving their dexterity by devising new mechanical structures and actuation systems. However, most of them rely on a single structure/system (e.g., bone-only) and ignore the fact that the human hand is composed of multiple functional structures (e.g., skin, bones, muscles, and tendons). This not only increases the difficulty of the design process but also lowers the robustness and flexibility of the fabricated hand. Besides, other factors like customization, the time and cost for production, and the degree of resemblance between human hands and robotic hands, remain omitted. To tackle these problems, this study proposes a 3D printable multi-layer design that models the hand with the layers of skin, tissues, and bones. The proposed design first obtains the 3D surface model of a target hand via 3D scanning, and then generates the 3D bone models from the surface model based on a fast template matching method. To overcome the disadvantage of the rigid bone layer in deformation, the tissue layer is introduced and represented by a concentric tube based structure, of which the deformability can be explicitly controlled by a parameter. Besides, a low-cost yet effective underactuated system is adopted to drive the fabricated hand. The proposed design is tested with 33 widely used object grasping types, as well as special objects like fragile silken tofu, and outperforms previous designs remarkably. With the proposed design, anthropomorphic robotic hands can be produced fast with low cost, and be customizable and deformable.