Fiber optic strain, temperature and shape sensing via OFDR for ground, air and space applications

Optical Frequency Domain Reflectometry (OFDR) is used to interrogate fiber sensors adhered to various structures. Temperatures in excess of 1000 degrees C are observed on a thermal-barrier coated stainless steel test plate as it is exposed to a high-temperature torch. The surface temperature distribution is mapped with 5 mm spatial resolution at 100 Hz, revealing large spatial and temporal thermal gradients at coating defect locations. Results and response times are compared with conventional K type thermocouples. Also presented in this work, are real-time position, shape and twist measurements of a simple structure as it is subjected to various loads.