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A fluorometer is a device that measures the spectroscopic properties of fluorescent materials, and fluorometry is used widely in chemistry research settings to characterize fluorescent samples. One of the obstacles faced by undergraduate programs looking to implement fluorometer-based experiments into their laboratory curriculum is the high cost of these instruments. We have designed a low-cost fluorometer that is suitable for teaching principles of fluorescence spectroscopy, and in this work, we provide instructions for the assembly and testing of this device. This home-built instrument, which we call the Fluorino, is constructed from inexpensive 3D printable optomechanical components, an Arduino Uno microcontroller, and low-cost optical and electronic components, and it is controlled by open-source software. Once assembled, the Fluorino can be used by students to measure and record fluorescence emission intensities in steady state as well as changes in fluorescence emission intensities in real time. This work represents an effort to expand accessibility to fluorescence spectroscopy education by providing a low-cost alternative to commercial instruments.

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This paper presents a refined methodology for performing helicopter transmission anomaly detection through the use of vibration separation techniques applied to the output of a fiber optic sensor array. Fiber Bragg grating (FBG) sensors—distributed about the exterior of a planetary gearbox annulus—record the local strain response of the annulus surface due to tooth-mesh interactions. These strain profiles are collected for a number of loading conditions both with and without seeded faults. The profiles are separated and synchronously averaged to illustrate the effect of damage to planetary gears on local strain variation. Results of experiments conducted on the University of Maryland Transmission Test Rig (UMTTR) are included. Additional processing and comparison to traditional vibration-based diagnostic methods indicate the potential for increased sensitivity to damage of such a system and the feasibility of fiber optic strain sensors for in situ health and usage monitoring.