Fiber optic speed sensor for advanced gas turbine engine control

A fiber optic speed sensor (FOSS) has been developed, bench tested and rig tested in a real turbine airflow environment. The FOSS employs an innovative design using a pressure tube and fiber optic microbend transducer in order to capture turbine blade pass wake frequency. The blade pass frequency can be converted by a signal processor into turbine rotational speed. The FOSS offers unique potential to meet future requirements for performance (0 to 25 KHz) and environmental tolerance (1200 F temperatures and EMI/EMP threats). Future efforts include development of the signal processor and environmental/durability testing focused on developing reliable, long life operation in the hostile environment of an advanced gas turbine engine.