Journal of the Aerospace Sciences最新文献

Energy Harvesting Process Modelling of an Aeronautical Structural Health Monitoring System Using a Bond-Graph Approach 基于键图法的航空结构健康监测系统能量收集过程建模

Journal of the Aerospace Sciences Pub Date : 2013-01-07 DOI: 10.5923/J.AEROSPACE.20120105.03

Thomas Sainthuile, S. Grondel, C. Delebarre, Stéphane Godts, C. Paget

{"title":"Energy Harvesting Process Modelling of an Aeronautical Structural Health Monitoring System Using a Bond-Graph Approach","authors":"Thomas Sainthuile, S. Grondel, C. Delebarre, Stéphane Godts, C. Paget","doi":"10.5923/J.AEROSPACE.20120105.03","DOIUrl":"https://doi.org/10.5923/J.AEROSPACE.20120105.03","url":null,"abstract":"Energy Harvesting is a pro mising solution for powering Structural Health Monitoring (SHM ) systems since various mechanical energy sources are generated by aircraft. Today, the main technique to harvest energy consists of using a specific conversion device to provide power to the SHM system. In this paper however, a novel technique to obtain a self-powered SHM system for aeronautical structures is proposed. This SHM system aims to have a double functionality: it will carry out classical SHM tasks using piezoelectric transducers bonded onto the aircraft structure and will also be fully autonomous since the same transducers will convert the mechanical v ibrations of the structure into electrical power. Using a bonded piezoelectric t ransducer to harvest energy will also bring wideband frequency energy harvesting capability. Th is autonomous system using a unique transducer being particularly innovative, the objective of this paper is to provide a complete Bond Graph model of the energy harvesting process in order to allow the optimisation of its performances. This approach is well-suited to monitor the power and energy transfer carried out during the process since it takes into account the interaction between mu ltiphysics systems, here the electrical and mechanical domains in terms of power and energy variables. Consequently, each part of the energy harvesting, i.e. the mechanical v ibration of the host structure, the vibration within the SHM energy harvester volume, the piezoelectric electro mechanical conversion and the terminal electric load have been modelled analytically using this Bond Graph approach. Then, each submodel has been verified with a baseline Fin ite Element model. Good agreements have been found and it has been possible to carry out an estimat ion of the power harvested by the SHM energy harvester for a given mechanical excitation using this innovative complete analytical Bond Graph model.","PeriodicalId":336301,"journal":{"name":"Journal of the Aerospace Sciences","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114603134","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Target-Multiplicity Analysis of CML Processor for Partially-Correlated χ2 Targets CML处理器部分相关χ2目标的目标多重性分析

Journal of the Aerospace Sciences Pub Date : 2013-01-07 DOI: 10.5923/J.AEROSPACE.20120105.02

M. B. Mashade

{"title":"Target-Multiplicity Analysis of CML Processor for Partially-Correlated χ2 Targets","authors":"M. B. Mashade","doi":"10.5923/J.AEROSPACE.20120105.02","DOIUrl":"https://doi.org/10.5923/J.AEROSPACE.20120105.02","url":null,"abstract":"Our scope in this paper is to treat the problem of detecting what is called moderately fluctuating targets when the operating environment is contaminated with a number of outlying targets along with the target under test (mult iple -target situations). The illu mination of this impo rtant class of radar targets by a coherent pulse train, return a train of correlate d pulses with a correlation coefficient in the range 0<ρ<1 (intermediate between SW II & SWI). To achieve this goal, we choo se the OS based type of adaptive detectors owing to its immunity to interfering targets. However, the homogeneous performance of OS technique is always lower than that of the CA scheme. Therefore, it is preferab le to choose the more efficient version, which co mbines the benefits of these two schemes, of the adaptive detectors. This modified version is known as censored mean-level (CM L) in the literature. It imp lements trimmed averaging of a weighted ordered range samp les. Here, the detection performance of the CM L processor is analyzed on the assumption that the radar receiver collects data fro m M successive pulses and the radar system operates in target multip licity environ ments. The primary as well as the secondary interfering targets fluctuates in accordance with χ 2 fluctuation model. SWI and SWII cases represent the situations where the signal is comp letely correlated and completely decorrelated, respectively, fro m pulse to pulse. Exact exp ressions are derived for the detection and false alarm rate perfor mances in nonideal situations. For weak SNR, it is shown that the processor performance imp roves as the correlation coefficient ρ increases and this occurs either in the absence or in the presence of outlying targets. This behavior is rapid ly changed as the SNR beco mes stronger where the p rocessor performance degrades as ρ increases, and the SWII and SWI models emb race all the correlated target cases.","PeriodicalId":336301,"journal":{"name":"Journal of the Aerospace Sciences","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123349074","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Deflection of Structures Using Principle of Quasi Work 利用准功原理研究结构的挠度

Journal of the Aerospace Sciences Pub Date : 2013-01-07 DOI: 10.5923/J.AEROSPACE.20120105.01

I. K. Panditta, M. Wani

引用次数: 9

Robust Active Vibration Control of Smart Structures; a Comparison between Two Approaches: µ-Synthesis & LMI-Based Design 智能结构的鲁棒主动振动控制微合成与lmi设计两种方法的比较

Journal of the Aerospace Sciences Pub Date : 2013-01-07 DOI: 10.5923/J.AEROSPACE.20120105.04

A. Oveisi, M. Gudarzi

引用次数: 5

Performance Analysis of CFAR Detection of Fluctuating Radar Targets in Nonideal Operating Environments 非理想工作环境下波动雷达目标CFAR检测性能分析

Journal of the Aerospace Sciences Pub Date : 2012-12-01 DOI: 10.5923/J.AJSP.20120205.03

M. B. Mashade

{"title":"Performance Analysis of CFAR Detection of Fluctuating Radar Targets in Nonideal Operating Environments","authors":"M. B. Mashade","doi":"10.5923/J.AJSP.20120205.03","DOIUrl":"https://doi.org/10.5923/J.AJSP.20120205.03","url":null,"abstract":"A constant false alarm rate in the presence of variable levels of noise is usually a requirement placed on any modern radar. The CA - and OS-CFAR detectors are the most widely used ones in the CFAR world. The cell-averaging (CA) is the optimu m CFA R detector in terms of detection probability in ho mogeneous background when the reference cells have identical, independent and exponentially distributed signals. The ordered-statistic (OS) is an alternative to the CA processor, which trades a small loss in detection performance, relative to the CA scheme, in ideal conditions for much less performance degradation in non-ideal background environments. To benefice the merits of these well-known schemes, two modified versions (MX- & MN-CFAR) have been recently suggested. This paper is devoted to the detection performance evaluation of these modified versions as well as a novel one (ML-CFA R). Exact formu las for their false alarm and detection performances are derived, in the absence as well as in the presence of spurious targets. The results of these performances obtained for Rayleigh clutter and Rayleigh target indicate that the MN-CFAR scheme performs nearly as good as OS detector in the presence of outlying targets and all the developed versions perform much better than that processor when the background environment is homogeneous. When compared to CA-CFAR, the modified schemes perform better in an ideal condition, and behave much better in the presence of interfering targets.","PeriodicalId":336301,"journal":{"name":"Journal of the Aerospace Sciences","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130630457","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

The Characteristics of Two-Dimensional Sails in Hypersonic Flow 高超声速流动中二维帆的特性

Journal of the Aerospace Sciences Pub Date : 2012-08-30 DOI: 10.2514/8.7483

W. Daskin

引用次数: 0

Minimum-Energy Intercepts Originating From a Circular Orbit 源自圆形轨道的最小能量拦截

Journal of the Aerospace Sciences Pub Date : 2012-08-30 DOI: 10.2514/8.9261

W. Tempelman

引用次数: 0

On the Stable Shape of an Ablating Graphite Body 烧蚀石墨体稳定形状的研究

Journal of the Aerospace Sciences Pub Date : 2012-08-30 DOI: 10.2514/8.7922

D. Christensen