Fiber optic accelerometer based on a Mach-Zehnder interferometer with long period gratings

• Grant number: 17/20128-2
• Support Opportunities: Scholarships in Brazil - Master
• Start date: March 01, 2018
• End date: July 31, 2020
• Field of knowledge: Engineering - Electrical Engineering - Electrical, Magnetic and Electronic Measurements, Instrumentation
• Agreement: Coordination of Improvement of Higher Education Personnel (CAPES)
• Principal Investigator: João Marcos Salvi Sakamoto
• Grantee: Walter Ferreira da Silva Junior
• Host Institution: Instituto de Estudos Avançados (IEAv). Departamento de Ciência e Tecnologia Aeroespacial (DCTA). Ministério da Defesa (Brasil). São José dos Campos , SP, Brazil
• Associated scholarship(s): 19/04986-4 - Manufacture and characterization of long period gratings (LPG) for mounting an optical fiber Mach-Zehnder interferometer, BE.EP.MS

Abstract

Inertial sensors are capable of determining the trajectory and attitude of a vehicle where they are fixed, without (or with restricted) utilization of external information (such as GPS signals), being used both on civilian and military applications (dual applications). For instance, airplanes, satellites, rockets, drones, cars, buses, tracts, robots, ships and submarines, autonomous or not, require this kind of sensor to accomplish a suitable navigation. Two type of inertial sensors are needed for such navigation to be possible: the gyroscopes and the accelerometers. It should be mentioned that the gyroscopes and accelerometers available in the market present precision bellow the one required for space navigation, for instance. The high precision sensors are up to nowadays, embargoed by the nations who dominate this kind of technologies, making the Brazilian government regard the development of this subject as a strategic one. In this work we propose the development of a fiber optic accelerometer based on optical interferometry by Long Period Gratings (LPG). The interferometer will be a Mach-Zehnder type, embedded on fiber. The sensor region (optical fiber region were the interference occurs) will be submitted to macrobending and, with a suitable mechanical structure, we intend to measure the acceleration as function of this macrobending. We intend to obtain a sensor that is lightweight, compact, with high resolution, precision, accuracy, repeatability, dynamic range, and robustness. (AU)