Design, simulation, and additive manufacturing performance of three lightweight FBG acceleration sensors

Low-weight, high-performance accelerometers are sought-after objectives in aerospace structural design. This paper presents three design schemes for lightweight FBG accelerometers: lattice-based (FBGL), reinforced (FBGR), and lattice-reinforced (FBGL-R) accelerometers. The influence of the design's filling factor (Fd) on the first-order frequency and sensitivity in three directions of the accelerometers is investigated. Additionally, the Additive Manufacturing (AM) performance of the designed accelerometers is explored and compared with the original model. The results demonstrate that the first-order natural frequencies of the three design models decrease linearly with increasing Fd, with FBGL-R exhibiting a larger adjustable range of low-frequency response under the same mass. FBGL shows the greatest sensitivity variation with Fd in all three directions, while FBGR exhibits the least sensitivity variation. Under the same mass fraction, FBGR demonstrates higher sensitivities in all three directions, with FBGL-R's performance falling between the other two designs. AM simulations indicate that the porous structures can reduce the deformation amplitude during the AM of FBG accelerometers. FBGL, FBGR, and FBGL-R exhibit approximately 7% lower deformations compared to the original sensor. The deformation distribution is similar among the four models, with larger residual deformations occurring at the outer edges of the components, while differences in deformation distribution exist within the porous regions.