Looking for more compact and integrated sensors for soft robotics? This paper introduces an optical fibre-based smart artificial muscle (OSAM) that estimates self-displacement using the bending loss of optical fibres integrated into the muscle's sleeve. The McKibben artificial muscle, a fluid-driven soft actuator, traditionally faces challenges in displacement sensing due to the unsuitability of bulky displacement sensors. Integrating optical fibres into the OSAM sleeve using a braiding machine simplifies mass production. Displacement is estimated based on changes in the optical fibre’s curvature and sensor output. Displacement feedback control experiments demonstrate the usefulness of OSAM, showing good response to target displacement. This artificial muscle facilitates displacement feedback control without requiring external sensors, enhancing performance in rehabilitation and wearable devices. The research provides a novel approach to integrating sensing capabilities directly into soft actuators.
This article, published in Smart Materials and Structures, is consistent with the journal's focus on advanced materials with integrated functionality. The development of an optical fibre-based smart artificial muscle aligns with the journal's interest in innovative materials and structures with sensing capabilities for various applications.