Abstract
Soft textile pressure sensors provide superior comfort for wearable systems but often suffer from limited compressibility, tunability, and complex postprocessing. A fully textile-based spacer-knitted piezoresistive pressure sensor is fabricated in a single step using a standard V-bed flat knitting machine with heat-expandable yarn inlays. The expandable inlays form highly compliant spacer regions, yielding effective compressive moduli of 54 and 77 kPa for the two- and four-inlay configurations. Sensor sensitivity is tunable through sensor size and internal architecture, ranging from −1.067 to −0.251%kPa⁻¹ for sensor sizes between 2.5 and 7.5 cm and from −0.678 to −0.180%kPa⁻¹ by varying spacer inlays and resistive yarn plies, while maintaining linear responses up to 60 kPa. Stable operation over 10000 loading cycles and preserved electrical integrity after ten washing cycles confirm suitability for long-term wearable and nonwearable pressure sensing applications. The real-world applicability of the proposed spacer-knitted pressure-sensitive structures is further demonstrated by a knee cuff and a 2 × 2 sensor matrix.