MagGami: An Electromagnetic Origami Actuator With High Stiffness‐Switching Density for Lightweight Joint‐Space Wearable Haptics

ABSTRACT

Kinesthetic feedback gloves play a central role in immersive virtual and augmented reality (VR/AR) by enabling the perception of object shape, stiffness, and spatial constraints. However, key challenges remain: 1) achieving a large stiffness contrast between free‐space and constrained‐space states, 2) enabling independent actuation on finger joints, and 3) maintaining lightweight, low‐power wearable operation. Here, we introduce MagGami, a miniaturized origami‐based variable‐stiffness actuator weighing 1.2 g for distributed joint‐space integration. By combining origami geometric interlocking with an electromagnetic bistable mechanism, it can be triggered by transient current pulses at the flattened 0° configuration of the origami mechanism. MagGami switches from a freely compliant state to a self‐locked high‐resistance state with a mean locking response time of 102.8 ms, while requiring no coil power to hold the locked state. The mean device‐level locked‐to‐free effective rotational‐stiffness ratio is 795.46, corresponding to a module‐level stiffness‐switching density of 6.63 × 10 ⁵ kg ^{− 1} , and the specified switching cycle consumes 444 mJ. MagGami uses distributed joint‐space actuation to deliver lightweight, independently addressable binary constraint cues at individual finger joints, thereby enhancing the perception of virtual spatial constraints and high‐resistance contact in VR/AR interactions. This work demonstrates a compact and energy‐efficient strategy for next‐generation wearable haptic interfaces.