Direct ink writing (DIW) 3D-printed sensors exhibit significant potential in aerospace structural health monitoring due to their design flexibility and high manufacturing precision. This paper reviews recent advances in the design

fabrication

and application of DIW sensors. First

we systematically summarize key breakthroughs in sensor design

including theoretical approaches for multilayer composite structures

optimized layouts for sensor arrays

integrated designs for embedded sensors

and decoupling strategies for multifunctional sensors. Regarding fabrication

we highlight the importance of process parameter optimization for controllable high-precision manufacturing

as well as the development of multi-axis printing systems for conformal deposition on complex curved surfaces. In terms of applications

successful implementations are demonstrated in aerospace structural monitoring

building vibration detection

human motion capture

and closed-loop control of soft robotics. Finally

we discuss current challenges and propose future research directions. Owing to its exceptional material compatibility and conformal printing capabilities

DIW technology is poised to become a critical tool for enhancing flight safety and extending equipment service life.