Laser Diode Profilometer for Remote Measurement of Ice Shapes

Rapid and accurate assessment of the degree of ice accretion on aerodynamic surfaces is a critical need in the aerospace industry. Even minimal accretion of ice can drastically affect the aerodynamic performance of aircraft and represents a serious safety risk factor. We propose a novel non-contacting optical profilometer system based on laser diodes in a unique configuration to measure both ice accretion thickness and surface shapes rapidly and with high accuracy. The operation characteristics of the laser diode and the system configuration are selected to maximize accuracy and to avoid artifacts from sub-surface reflections. High speed data acquisiton rates make it possible to measure rotating surfaces and sub-millimeter resolution makes the instrument attractive for commercial spin-off applications such as in automated inspection and assembly.