Embodied Manipulation with Past and Future Morphologies through an Open Parametric Hand Design

TL;DR

This paper presents an open, customizable parametric robotic hand design that enables rapid fabrication and diverse manipulation behaviors, facilitating exploration of morphological design space and advancing dexterous robotic manipulation.

Contribution

Introduction of a novel open parametric hand design integrating simplified customization, fabrication, and control to maximize behavioral diversity and facilitate morphological exploration.

Findings

Demonstrated a wide range of low-level behaviors and stability in the design.

Fabricated and tested three distinct hand morphologies with unique manipulation capabilities.

Showcased emergent behaviors and proficiency variations across different hand designs.

Abstract

A human-shaped robotic hand offers unparalleled versatility and fine motor skills, enabling it to perform a broad spectrum of tasks with precision, power and robustness. Across the paleontological record and animal kingdom we see a wide range of alternative hand and actuation designs. Understanding the morphological design space and the resulting emergent behaviors can not only aid our understanding of dexterous manipulation and its evolution, but also assist design optimization, achieving, and eventually surpassing human capabilities. Exploration of hand embodiment has to date been limited by inaccessibility of customizable hands in the real-world, and by the reality gap in simulation of complex interactions. We introduce an open parametric design which integrates techniques for simplified customization, fabrication, and control with design features to maximize behavioral diversity. Non-linear rolling joints, anatomical tendon routing, and a low degree-of-freedom, modulating, actuation system, enable rapid production of single-piece 3D printable hands without compromising dexterous behaviors. To demonstrate this, we evaluated the design's low-level behavior range and stability, showing variable stiffness over two orders of magnitude. Additionally, we fabricated three hand designs: human, mirrored human with two thumbs, and aye-aye hands. Manipulation tests evaluate the variation in each hand's proficiency at handling diverse objects, and demonstrate emergent behaviors unique to each design. Overall, we shed light on new possible designs for robotic hands, provide a design space to compare and contrast different hand morphologies and structures, and share a practical and open-source design for exploring embodied manipulation.