Abstract:

This paper presents a technique to fill the void in on-site calibration of accelerometers in helicopter health and usage monitoring systems (HUMS) within low frequency range.The technique employs a compact linear-motor-driven reference vibration exciter and a thermo-stabilized quartz flexible accelerometer to construct a portable,precise,and stable calibrating apparatus,which is quite fit for the on-site calibration of helicopter HUMS. According to the uncertainty estimation and calculation,an expanded calibrating uncertainty (k=2) of no more than 1% is expected of the apparatus over the frequency range of 0.5 Hz~20Hz and the acceleration range of 0.01 m/s²~20 m/s².

Key words: Health and usage monitoring systems, Accelerometers, Vibration in low frequency range, On-site calibration, Linear motor