Aplicações de sensores a fibra óptica integrados em materiais compósitos

Abstract

The present work shows the study of composite materials using fiber optic sensors based on Bragg grating (FBG) and the application of this technology to the area of human and animal biomechanics. In human biomechanics, two models of prostheses for lower limb amputees were developed, being a transtibial prosthesis and a prosthesis of the foot. Both prostheses are made of composite material with integrated FBGs sensors. Axial compression tests were performed to characterize the prostheses. The mean sensitivity of the sensors is 10 pm/N. From the results of the mechanical tests, the transtibial prosthesis was simulated in Ansys student software 19.2. The obtained values of deformation (μStrain) were of the same order of magnitude of the results obtained experimentally. The simulation helped to customize a new transtibial prosthesis model. The characterization of the prostheses during the gait cycle was performed from the FBGs sensor readings while a volunteer performed the walking movement. These trials were performed with a mechanical adaptation and with the help of three non-amputated volunteers. In the test three different speeds of an ergometric treadmill were used. The obtained results were processed and presented in an interactive way through a color map and vector diagrams. The optical instrumentation used in this work contributes to the development of a new tool for evaluation of the prosthesis design, rehabilitation of amputees and for the evaluation of the performance of athletes during training or competition. In area of animal biomechanics, horseshoes made from composite material and instrumented with FBGs sensors were developed to monitor horse gait. Equine trials were performed in three types of gait: step, trot and gallop. Optical instrumentation for equines contributes to identify patterns of walking and to avoid pathologies related to the animal's hoof. The technologies developed in this work demonstrate the potential of applications involving fiber optic sensors integrated in composite materials.