Stiffness Control of Laminar Jammers With Fused Layers: A Discrete Approach

Laminar jamming, a technique in soft robotics for regulating structural rigidity, traditionally relies on vacuum pressure activation. Recent studies are exploring discrete jamming methods for enhanced portability in soft actuators. This letter investigates stiffness control in a fused laminar structure whose layers are made of 400 grit sandpaper bonded with 75 gsm printer copy paper, and the structure is discretely jammed using custom 3D-printed mini pressure clamps. It presents the concept, design, fabrication, and characterization of the fused jammer. Findings show that increasing separation among laminar layers reduces the structure's rigidity during bending. The study also explores the impact of discrete pressure's location and coverage area on stiffness, revealing that applying pressure closer to the fixed end of the jammer maximizes stiffness. The fabricated fused jammer achieves significantly higher stiffness, up to five times that of a traditional homogeneous jammer made solely of printer paper.