Characterisation of a Plastic Fibre-Based Weighing System for the 0-50 kg Range

摘要

This paper describes the design, construction and characterisation of an optical fibre-based system for determining mass by weight. This inexpensive system consisted of a short length of polymer fibre, an AlInGaP light emitting diode and a general purpose BPX-65 photodiode detector. Signal conditioning was performed using an I-V converter, shift amplifier and offset control prior to data acquisition and display using a Visual Basic program. The characteristics of the system, including linearity, sensitivity, repeatability and hysteresis have been investigated. The device was shown to be approximately linear in the 0-50 kg weighing range with a resolution of 1 kg. However, hysteresis effects, presumably related to the plasticity of the fibre, were non-negligible.