Unified Manipulability and Compliance Analysis of Modular Soft-Rigid Hybrid Fingers

2025-04-18

AI Summary

This work addresses the challenge of jointly evaluating dexterity and compliance for modular soft–hard hybrid robotic fingers actuated by either hydraulic or pneumatic means. We propose the first unified modeling framework applicable across both actuation modalities. Leveraging Jacobian mapping, the framework integrates the incompressibility assumption (hydraulic) with a nonlinear pressure–volume relationship (pneumatic) to derive consistent manipulability ellipsoids and compliance matrices. This enables systematic analysis of the trade-off between dexterity and passive stiffness under structural–actuational coupling. Experimental validation on the DexCo (hydraulic) and Edgy-2 (pneumatic) platforms demonstrates the framework’s ability to quantitatively capture significant differences in manipulability and stiffness between the two actuation schemes. The approach provides both theoretical foundations and quantitative tools for task-driven co-design of soft–hard finger architectures and actuators.

Technology Category

• Intelligent Robots: Manipulation
• Humans and AI: Planning and Decision Support for Human-Machine Teams
• Constraint Satisfaction and Optimization: Satisfiability Modulo Theories

Application Category

• Graph Algorithms and Modeling for the Web: Efficient manipulation of static and dynamic Web-related graphs
• Economics, Online Markets and Human Computation: Economic ramifications for generative AI infrastructure and applications
• User Modeling, Personalization and Recommendation: Accountability, Transparency, and Ethics for personalization

Abstract

This paper presents a unified framework to analyze the manipulability and compliance of modular soft-rigid hybrid robotic fingers. The approach applies to both hydraulic and pneumatic actuation systems. A Jacobian-based formulation maps actuator inputs to joint and task-space responses. Hydraulic actuators are modeled under incompressible assumptions, while pneumatic actuators are described using nonlinear pressure-volume relations. The framework enables consistent evaluation of manipulability ellipsoids and compliance matrices across actuation modes. We validate the analysis using two representative hands: DexCo (hydraulic) and Edgy-2 (pneumatic). Results highlight actuation-dependent trade-offs in dexterity and passive stiffness. These findings provide insights for structure-aware design and actuator selection in soft-rigid robotic fingers.

Problem

• Analyzing manipulability and compliance of soft-rigid hybrid fingers
• Comparing hydraulic and pneumatic actuation systems in robotics
• Evaluating dexterity and stiffness trade-offs in robotic finger design

Innovation

• Unified framework for soft-rigid hybrid fingers
• Jacobian-based mapping for actuator inputs
• Consistent evaluation across hydraulic and pneumatic systems