Multi-Mode Pneumatic Artificial Muscles Driven by Hybrid Positive-Negative Pressure

2026-03-16

AI Summary

This study addresses the limitations of conventional pneumatic artificial muscles, which struggle to simultaneously achieve multimodal actuation, thin profiles, and high flexibility—constraints that hinder their use in flexible wearable devices and compact soft robots. To overcome this, the authors propose an origami-inspired inflatable fluidic actuator, termed IN-FOAM, which integrates hybrid positive–negative pressure actuation, a programmable skeletal structure, and a multilayer, multichannel architecture to enable diverse motion modes including contraction, bending, twisting, and rotation. The design substantially enhances output force and strain ratio while maintaining an ultrathin, lightweight, and portable form factor. Fabricated using low-cost heat-sealable films and thermal lamination, IN-FOAM’s mechanical performance is validated through experiments, theoretical analysis, and simulations, demonstrating its significant potential for applications in soft robotics and wearable systems.

Technology Category

• Intelligent Robots: Multimodal Perception & Sensor Fusion
• Humans and AI: Human-Aware Planning and Behavior Prediction
• Machine Learning: Hardware-aware ML

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Applied ML and AI for Web-based mobile applications
• Responsible Web: Machine-in-the-loop, human agency and autonomy
• User Modeling, Personalization and Recommendation: On-Device user modeling, personalization, and recommendation

Abstract

Artificial muscles embody human aspirations for engineering lifelike robotic movements. This paper introduces an architecture for Inflatable Fluid-Driven Origami-Inspired Artificial Muscles (IN-FOAMs). A typical IN-FOAM consists of an inflatable skeleton enclosed within an outer skin, which can be driven using a combination of positive and negative pressures (e.g., compressed air and vacuum). IN-FOAMs are manufactured using low-cost heat-sealable sheet materials through heat-pressing and heat-sealing processes. Thus, they can be ultra-thin when not actuated, making them flexible, lightweight, and portable. The skeleton patterns are programmable, enabling a variety of motions, including contracting, bending, twisting, and rotating, based on specific skeleton designs. We conducted comprehensive experimental, theoretical, and numerical studies to investigate IN-FOAM's basic mechanical behavior and properties. The results show that IN-FOAM's output force and contraction can be tuned through multiple operation modes with the applied hybrid positive-negative pressure. Additionally, we propose multilayer skeleton structures to enhance the contraction ratio further, and we demonstrate a multi-channel skeleton approach that allows the integration of multiple motion modes into a single IN-FOAM. These findings indicate that IN-FOAMs hold great potential for future applications in flexible wearable devices and compact soft robotic systems.

Problem

• Pneumatic Artificial Muscles
• Soft Robotics
• Multi-Mode Actuation
• Wearable Devices
• Origami-Inspired Design

Innovation

• pneumatic artificial muscle
• origami-inspired actuator
• hybrid pressure driving
• programmable skeleton
• soft robotics