Design and Fabrication of a Fiber-Optic Interferometric Accelerometer System
Abstract
Two fiber-optic accelerometer designs are presented. The first accelerometer was constructed using two flexural disks between which is a center spindle. Six uniformly spaced screws fasten the disk assembly to a circular, hollow base housing fiber-optic couplers and splices and providing fiber access. The disk edge is elastically restrained. A flat spirally wound coil of optical fiber is bonded to one surface of each disk. Disk surface strains, caused by acceleration, are detected in a push-pull fashion by fiber coils comprising the legs of a Mach-Zender optical interferometer. This sensor demonstrated an acceleration sensitivity of 2.3 + 0.1 rad/g a bandwidth of 150-475 Hz. The resonance frequency ,as 1.22 + or -0.05 kHz. The second accelerometer design described exploits the benefits of using a disk material having a significantly slower sound speed than aluminum; in general, a slower sound speed increases the acceleration sensitivity and decreases the resonance frequency. One polycarbonate disk with a simply supported edge condition is fastened between an aluminum cap and an aluminum housing base secured with six uniformly spaced screws. One flat fiber coil in each Mach-Zender interferometer leg was bonded to each disk surface. This sensor demonstrated an acceleration sensitivity of 56.9 + 4.0 rad/g over a bandwidth of 30-950 Hz. The resonance frequency was 1.7 + 0. 05 kHz.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1992
- Accession Number
- ADA253021
Entities
People
- Mary Beth A. Chipkevich
Organizations
- Naval Postgraduate School