Soft materials can be trained to stiffen exactly like human muscle simply by shaking or squeezing them during the manufacturing process.
April 24, 2026
Original Paper
Programming strain-stiffening in soft composites via structural memory near jamming
arXiv · 2604.20437
The Takeaway
Soft composites encode structural memory into their internal contact networks to program their physical strength. By applying specific strains as the material is being made, engineers can dictate how it will react to being pulled or pushed later on. This mimics the way biological tissues like tendons and skin get stronger as they are used. You don't need fancy polymers or complex chemicals to achieve this, it's all about how the internal particles are jammed together. This allows for the creation of low-cost, smart materials for robotics and wearable tech that feel and act like real biological matter.
From the abstract
Soft composite solids, comprising discrete inclusions embedded within a compliant matrix, are emerging candidates for engineering synthetic tissues and soft robotic materials. Current strategies for controlling their nonlinear mechanics, such as strain-stiffening, have primarily relied on the nonlinear elasticity of polymer matrices. Although direct contacts between inclusions may enhance stiffening responses at high densities, the role of the non-equilibrium and history-dependent nature of diso