Two variations of each of three types of digital optical transducers have been developed to provide the technology base for a digital optical flight control system for US Army helicopters. The transducer types are rotary position, linear position, and differential hydraulic pressure and all are electrically passive at the transducer location. The development and test of these six transducers has led to the selection of a reflective, time delay multiplexed concept using a single interconnecting fiber for use on the Advanced Digital Optical Control System Flight Demonstrator Program (ADOCS FDP).
Russell O. Stanton,
"Digital Optical Transducers For Helicopter Flight Control Systems", Proc. SPIE 0412, Fiber Optic and Laser Sensors I, (19 September 1983); doi: 10.1117/12.935805; https://doi.org/10.1117/12.935805