Magnetic field-assisted 3D printing of magnetic self-powered sensors

Triply periodic minimal surface (TPMS) based lattices have drawn great attention in recent years due to their lightweight, design flexibility and compatibility with 3D printing. However, more effort should be made in the functionality enhancement of engineered sensors, especially with field-assisted 3D printing methods. In this study, magnetic field-assisted photopolymerisation (MF-VP) 3D printing technique was employed to fabricate magnetic Schwarz primitive TPMS (P-TPMS) lattice. Based on the fabricated magnetic P-TPMS lattices, a self-powered sensor was designed to achieve the velocity-to-electrical signal conversion process without the need for external power supply. MF-VP 3D printing technique significantly improved the mechanical compressive performance of the magnetic P-TPMS lattice in the carbonyl iron powder alignment direction, magnetic properties and sensing capabilities. The magnetic P-TPMS lattice self-powered sensor exhibited outstanding stability and durability, maintaining highly stable relative output voltage signals after 10,000 compression cycles. The developed sensor successfully detected toy car impact processes and foot movement states (stop/slow/fast), highlighting the practical application potential of the self-powered sensor.