Mechanical non-reciprocity programmed by shear jamming in soft composite solids

TL;DR

This paper presents a novel approach to engineer non-reciprocal mechanics in soft composite solids by leveraging shear jamming transitions, enabling tunable asymmetric responses and programmable dynamics for advanced soft material applications.

Contribution

It introduces a new design principle using shear jamming in soft composites to achieve tunable and programmable non-reciprocal mechanical responses, bridging granular physics and soft material engineering.

Findings

Achieved tunable asymmetric shear and normal responses.

Demonstrated programmable non-reciprocal dynamics with magnetic responsiveness.

Established a new paradigm for non-reciprocal matter design.

Abstract

Mechanical non-reciprocity-manifested as asymmetric responses to opposing mechanical stimuli-has traditionally been achieved through intricate structural nonlinearities in metamaterials. However, continuum solids with inherent non-reciprocal mechanics remain underexplored, despite their promising potential for applications such as wave guiding, robotics, and adaptive materials. Here, we introduce a design principle by employing the shear jamming transition from granular physics to engineer non-reciprocal mechanics in soft composite solids. Through the control of the interplay between inclusion contact networks and matrix elasticity, we achieve tunable, direction-dependent asymmetry in both shear and normal mechanical responses. In addition to static regimes, we demonstrate programmable non-reciprocal dynamics by combining responsive magnetic profiles with the anisotropic characteristics of shear-jammed systems. This strategy enables asymmetric spatiotemporal control over motion transmission, a previously challenging feat in soft materials. Our work establishes a novel paradigm for designing non-reciprocal matter, bridging granular physics with soft material engineering to realize functionalities essential for mechano-intelligent systems.