Vibrometry by laser-doppler technology

Important results from the project

The aim of the project has been to develop a method for primary calibration of accelerometers with laser Doppler technology. This technology provides the ability to calibrate accelerometers at higher frequencies and has a more robust optical hardware than existing methodology. The technique can be applied to both sine and shock excitation of accelerometers. Primary measurement technology for shocks in turn provides preconditions for the realization of dynamic force.

Expected long term effects

The project has shown that it is possible to build a measuring system for primary calibration of accelerometers with robust optics from a modified commercial laser vibrometer. As the system generates large amounts of data that take time to process, an opportunity has been identified to decimate data before digitalisation, which is expected to reduce the calculation time significantly. The developed system is expected to eventually replace existing methods for primary calibration and increase the NMI´s ability to calibrate accelerometers at high frequencies.

Approach and implementation

The project began with literature studies to find a basis for decisions on system solutions. Thereafter, practical tests were performed on alternative reflex treatments to find an optimal measuring surface for the laser interferometer. The measurement system´s hardware was configured, after which the software development began. A conclusion of an analysis of the project implementation, is that the software development has been more challenging than expected.