AMS Technologies has introduced a polymer optical fibre (POF)-based strain sensor solution for industrial applications.
Based on a patented optical phase interrogation (OPI) technique, the solution enables the POF to be used as a high-precision strain sensor on par with current fibre Bragg grating (FBG)-based strain sensors. Applications include wind-blade load management in wind turbines and structural health monitoring for other structures.
The optical sensor employs the POF to form a ‘meander path’ sensor array that allows a single fibre to form multiple loops that fit in a confined area. When strained, these loops will alter the phase of an optical signal injected into the fibre.
A separate reference loop that is not strained surrounds the meander path and is used to compare the reference signal to the strained signal, and the difference in phase between the two signals can be converted into the strain measurement. The reference fibre simultaneously provides temperature compensation. The sensing array only contains optical fibres and is immune to EMI and EMC related interference and is electrically isolated from the rest of the system.