A Novel On-Site Primary Accelerometer Calibration Method Based on Homodyne Self-Traceable Grating Interferometer

As a key component in motion state sensing, the accuracy of accelerometers directly affects the performance and safety of their systems. However, their sensitivity can be influenced due to various factors during operation, necessitating both pre-deployment and periodic calibration. Traditional primary calibration methods rely on laser interferometers, yet their trueness and stability are compromised by environmental disturbances affecting the laser wavelength, making on-site traceability challenging. Addressing these issues, this study combines a Cr self-traceable grating with a homodyne Littrow grating interferometer and primary vibration calibration technique. Leveraging the high line density, stability, and traceability of the self-traceable grating, it achieves high accuracy and on-site traceable calibration. In experiments, the effectiveness of this calibration system was validated using commercial accelerometers, achieving a measurement uncertainty of 0.25%. This calibration technique not only enhances the accuracy and environmental adaptability of accelerometer calibration but also addresses the critical issue of on-site traceability, representing the future direction of in-field accelerometer calibration.