A Low Cross-Axis Sensitivity Micro-Grating Accelerometer With Double-Layer Cantilever Beams

Abstract

The micro-grating accelerometer based on the optical interference displacement measurement method has strict requirements on the parallelism of the interferometer and is susceptible to external interference. This paper proposes a micro-grating accelerometer with double-layer cantilever beams to suppress the effect of cross-axis acceleration and angular acceleration on the performance of the accelerometer. The mechanical characteristics of the designed double-layer cantilever beams structure and the conventional single-layer cantilever beams structure are compared by the finite element method. Theoretical results show that the symmetrical design of the double-layer cantilever beams structure can effectively reduce the cross-axis sensitivity. Under the same limit resolution, the torsional stiffness is increased by 50 times, which effectivity suppresses the disturbance of angular acceleration. The experimental results demonstrate that the designed structure has excellent linearity performance and low cross-axis sensitivity. The nonlinearity is reduced from 0.35% to 40.6 ppm, and the cross-axis sensitivity is better than 64.4 ppm.