A N ovel Fiber Optic System for Measuring the Dynamic Structural Behavior of Parachutes

A novel approach has been developed for real-time characterization of a parachute during inflation. Two techniques were applied to measure static and dynamic stresses in a parachute canopy fabric material and suspension lines: the modal power distribution (MPD) technique and the fiber Bragg grating (FBG) technique. Several tests were conducted under various loading conditions, using a bi-axial tensile tester. The MPD technique was used to measure the transverse stresses in the parachute canopy fabric material and was applied using two experimental set-ups: one using a CCD camera and the other using a photo-detector. The FBG technique was used to measure the axial stresses in the parachute canopy fabric material. The tests were performed using the spectrum analyzer set-up with the bi-axial machine. Finally, a drop test was performed on the parachute canopy fabric material using the MPD technique with the photo-detector set-up.