Plural-wavelength flame detector that discriminates between direct and reflected radiation

A flame detector employs a plurality of wavelength selective radiation detectors and a digital signal processor programmed to analyze each of the detector signals, and determine whether radiation is received directly from a small flame source that warrants generation of an alarm. The processor's algorithm employs a normalized cross-correlation analysis of the detector signals to discriminate between radiation received directly from a flame and radiation received from a reflection of a flame to insure that reflections will not trigger an alarm. In addition, the algorithm employs a Fast Fourier Transform (FFT) frequency spectrum analysis of one of the detector signals to discriminate between flames of different sizes. In a specific application, the detector incorporates two infrared (IR) detectors and one ultraviolet (UV) detector for discriminating between a directly sensed small hydrogen flame, and reflections from a large hydrogen flame. The signals generated by each of the detectors are sampled and digitized for analysis by the digital signal processor, preferably 250 times a second. A sliding time window of approximately 30 seconds of detector data is created using FIFO memories

Study Of Design Parameters In Hydrogen Microsensors Integrated With Metal Semiconductor Nanoparticles

We investigated the effect of electrode design parameters on the performance of hydrogen microsensors. The sensors with varying electrode parameters were fabricated integrating micromachined interdigitated electrodes with indium oxide (In2O3) doped polycrystalline tin dioxide (SnO2) nanoparticles and tested in a controlled gas environment. It was observed that the sensitivity was closely related to the gap between, and a ratio of the gap to the width in interdigitated electrodes (IDE)

Study Of Design Parameters In Hydrogen Microsensors Integrated With Metal Semiconductor Nanoparticles

We investigated the effect of electrode design parameters on the performance of hydrogen microsensors. The sensors with varying electrode parameters were fabricated integrating micromachined interdigitated electrodes with indium oxide (In2O3) doped polycrystalline tin dioxide (SnO2) nanoparticles and tested in a controlled gas environment. It was observed that the sensitivity was closely related to the gap between, and a ratio of the gap to the width in interdigitated electrodes (IDE). Copyright © 2007 by ASME

Advanced Data Acquisition Systems with Self-Healing Circuitry

Kennedy Space Center's Spaceport Engineering & Technology Directorate has developed a data acquisition system that will help drive down the cost of ground launch operations. This system automates both the physical measurement set-up function as well as configuration management documentation. The key element of the system is a self-configuring, self-calibrating, signal-conditioning amplifier that automatically adapts to any sensor to which it is connected. This paper will describe the core technology behind this device and the automated data system in which it has been integrated. The paper will also describe the revolutionary enhancements that are planned for this innovative measurement technology. All measurement electronics devices contain circuitry that, if it fails or degrades, requires the unit to be replaced, adding to the cost of operations. Kennedy Space Center is now developing analog circuits that will be able to detect their own failure and dynamically reconfigure their circuitry to restore themselves to normal operation. This technology will have wide ranging application in all electronic devices used in space and ground systems