High speed weigh-in motion measurement with Bragg grating sensors

In this paper, a high speed fiber optic sensor weigh-in-motion (WIM) system is proposed. Bragg gratings which have several advantages such as good reproducibility and good multiplicity compare to other optical fiber sensors are used for the system. Fabry-Perot filter for the signal process, which cannot be used in the high speed measurement because of the limitation in fast operation of PZT, is excluded. A new signal processing system which employs bandwidth filter is proposed and bridge type new sensor package design is also proposed. The proposed fiber optic WIM system is tested in the laboratory and experimented with actual trucks. The new concept of calibration coefficient "k" is introduced and calculated by the experiments. The calculated calibration coefficients show good approximations to real axial weights regardless tire widths.