A New Multifunctional Subresonant and Resonant Mechanical Spectrometer

A new mechanical spectrometer working in a resonant and subresonant mode is described. Basic principles and technical details of the design are briefly described. The mechanical spectrometer operates in the frequency range from 10-4 Hz to 50 Hz. High accuracy of the measurement of mechanical loss angle jtan, below 1 × 10-4, is achieved with an average resolution of the order of 3 × 10-6. The signal quality test of forced vibrations and free decay performed by the wavelet transform and the Fourier transform proves to be helpful in improving the resolution of the mechanical spectrometer. The general concept of the mechanical spectrometer operating both in a resonant and in a subresonant mode is briefly discussed. First experimental results are reported.