劉瑞霞 張會(huì)焱 杜煥超 徐元博
摘要
針對(duì)有限通信情形下航天器自主交會(huì)的故障檢測(cè)問題,提出了基于Delta算子的魯棒故障檢測(cè)濾波器設(shè)計(jì)方法.采用C-W方程來描述航天器間的相對(duì)運(yùn)動(dòng)模型,通過Delta算子方法對(duì)其進(jìn)行離散化處理得到系統(tǒng)的離散模型.在故障檢測(cè)濾波器設(shè)計(jì)中,考慮信號(hào)量化和數(shù)據(jù)丟包同時(shí)存在的情況,并且采用隨機(jī)伯努利序列來描述數(shù)據(jù)丟包現(xiàn)象.最后,基于LMI方法給出故障診斷存在的充分條件,并通過數(shù)值仿真驗(yàn)證了所設(shè)計(jì)濾波器的有效性.
關(guān)鍵詞
航天器自主交會(huì);故障檢測(cè);Delta算子;信號(hào)量化;數(shù)據(jù)丟包
中圖分類號(hào) TP273
文獻(xiàn)標(biāo)志碼 A
0 引言
隨著工業(yè)控制過程對(duì)性能、安全性和可靠性標(biāo)準(zhǔn)要求的不斷提高,故障檢測(cè)問題已引起人們廣泛關(guān)注[1].通常故障檢測(cè)過程分為兩步,首先構(gòu)造一個(gè)用來檢測(cè)故障信號(hào)的殘差信號(hào),其次設(shè)計(jì)一個(gè)殘差評(píng)價(jià)函數(shù),通過該函數(shù)與預(yù)設(shè)定的閾值進(jìn)行比較來判斷是否有故障,當(dāng)殘差值大于閾值時(shí),產(chǎn)生一個(gè)故障報(bào)警[2-3].值得指出的是,現(xiàn)有的大量關(guān)于故障診斷的研究成果多是針對(duì)連續(xù)系統(tǒng)或是通過傳統(tǒng)移位算子方法得到的離散系統(tǒng)[4]. 然而,在傳統(tǒng)的移位算子框架下,當(dāng)采樣周期減小時(shí),所有的信號(hào)和系統(tǒng)系數(shù)矩陣都會(huì)出現(xiàn)病態(tài)現(xiàn)象,因而無法將原始的連續(xù)時(shí)間系統(tǒng)等效為高頻采樣數(shù)據(jù)系統(tǒng).慶幸的是基于Delta算子算法的提出能夠有效地解決這一問題[5-7].目前Delta算子模型已經(jīng)被廣泛應(yīng)用于許多實(shí)際系統(tǒng).
另一方面,隨著載人航天技術(shù)的飛速發(fā)展,航天器自主交會(huì)已成為最重要的問題之一,并取得了一系列研究成果.在這些研究成果中,最廣泛被使用的數(shù)學(xué)工具之一便是Clohessy-Wiltshire(C-W)方程,它是由Clohessey 和 Wiltshire在1960年提出的.C-W方程被廣泛應(yīng)用于描述兩個(gè)相鄰航天器之間的線性運(yùn)動(dòng).近年來,C-W方程已被用于航天器自動(dòng)交會(huì)領(lǐng)域的研究.
在實(shí)際的航天工程中,航天器總是采用無線網(wǎng)絡(luò)進(jìn)行通信,不可避免地會(huì)出現(xiàn)網(wǎng)絡(luò)誘導(dǎo)現(xiàn)象,如信號(hào)量化和數(shù)據(jù)包丟失等[8-9].然而,到目前為止,基于網(wǎng)絡(luò)控制與濾波的航天器交會(huì)研究還很少.由于空間環(huán)境的復(fù)雜性,航天器在機(jī)動(dòng)過程中極易發(fā)生故障.顯然,這些故障會(huì)嚴(yán)重影響航天器的軌道機(jī)動(dòng)性能甚至導(dǎo)致航天任務(wù)無法完成.因此,針對(duì)航天器自主交會(huì)設(shè)計(jì)故障檢測(cè)濾波器是十分有必要的.該故障診斷器不僅要對(duì)不可避免的系統(tǒng)建模誤差或外部干擾具有魯棒性,而且還必須對(duì)故障敏感.因此,在故障檢測(cè)濾波器設(shè)計(jì)中采用Delta算子方法.據(jù)筆者所知,考慮信息量化和數(shù)據(jù)丟包同時(shí)存在的情況下,基于Delta算子的航天器交會(huì)魯棒故障檢測(cè)還鮮有研究,這仍然是一個(gè)重要而具有挑戰(zhàn)性的課題.
1 問題描述
考慮目標(biāo)航天器的軌道是圓軌道,且目標(biāo)航天器和追蹤航天器之間的距離很小.定義如下相對(duì)坐標(biāo)系:軌道坐標(biāo)系是一個(gè)右手坐標(biāo)系,其原點(diǎn)與目標(biāo)航天器質(zhì)心相連,x軸與從地心到目標(biāo)質(zhì)心的矢量對(duì)齊.y軸沿目標(biāo)航天器軌道的周長(zhǎng)方向,z軸與x軸和y軸呈右手坐標(biāo)系.兩個(gè)航天器之間的相對(duì)運(yùn)動(dòng)的線性化方程可以描述為
4 結(jié)束語
本文采用Delta算子方法,研究了輸出信號(hào)存在量化和隨機(jī)數(shù)據(jù)包丟失情形下的航天器自主交會(huì)故障檢測(cè)濾波器設(shè)計(jì)問題.對(duì)于系統(tǒng)中輸出信號(hào)的連續(xù)丟包現(xiàn)象通過一個(gè)服從伯努利序列的隨機(jī)變量來描述.通過設(shè)計(jì)一種魯棒的故障檢測(cè)濾波器使得故障檢測(cè)系統(tǒng)是隨機(jī)穩(wěn)定的且滿足H∞性能.通過采用線性矩陣不等式方法,給出了故障診斷濾波器存在的充分條件.最后,通過數(shù)值算例驗(yàn)證了所提方法的有效性.
參考文獻(xiàn)
References
[1]
Chen B,Niu Y G,Zou Y Y.Adaptive sliding mode control for stochastic Markovian jumping systems with actuator degradation[J].Automatica,2013,49(6):1748-1754
[2] Elia N,Mitter S K.Stabilization of linear systems with limited information[J].IEEE Transactions on Automatic Control,2001,46(9):1384-1400
[3] Gao Y B,Shi P,Li H Y,et al.Output tracking control for fuzzy delta operator systems with time-varying delays[J].Journal of the Franklin Institute,2015,352(7):2951-2970
[4] Kwak D H,Lee D H,Ahn J H,et al.Fault detection of roller-bearings using signal processing and optimization algorithms[J].Sensors,2013,14(1):283-298
[5] Li H Y,Gao Y B,Shi P,et al.Output-feedback control for T-S fuzzy delta operator systems with time-varying delays via an input-output approach[J].IEEE Transactions on Fuzzy Systems,2015,23(4):1100-1112
[6] Niu Y G,Ho D W C,Li C W.Filtering for discrete fuzzy stochastic systems with sensor nonlinearities[J].IEEE Transactions on Fuzzy Systems,2010,18(5):971-978
[7] Niu Y G,Liu Y H,Jia T G.Reliable control of stochastic systems via sliding mode technique[J].Optimal Control Applications and Methods,2013,34(6):712-727
[8] Yang H J,Li X,Liu Z X,et al.Fault detection for uncertain fuzzy systems based on the delta operator approach[J].Circuits,Systems,and Signal Processing,2014,33(3):733-759
[9] Yang H J,Zhang L Y,Zhao L,et al.Fault-tolerant control of delta operator systems with actuator saturation and effectiveness loss[J].International Journal of Systems Science,2016,47(10):2428-2439
Robust fault detection filter for spacecraft autonomous rendezvous via delta operator method
LIU Ruixia1 ZHANG Huiyan2 DU Huanchao1 XU Yuanbo1
1 School of Automation,Xian University of Posts & Telecommunications,Xian 710121
2 National Research Base of Intelligent Manufacturing Service,Chongqing Technology and Business University,Chongqing 400067
Abstract This paper addresses the robust fault detection problem for spacecraft autonomous rendezvous with digital communication constraints.The Clohessy-Wiltshire equation is employed to describe the relative dynamic model,and the discrete-time model with sampling behavior is proposed by using delta operator approach.In this design,the data are exchanged among components of spacecraft,and signal quantization and data packet losses are considered in a unified framework.The stochastic variables with Bernoulli random binary distribution are utilized to describe the random rate dropout.A sufficient condition for the existence of the designed fault detection filter is presented with linear matrix inequalities techniques.Finally,a practical example is illustrated to demonstrate the effectiveness of the proposed fault detection techniques.
Key words spacecraft rendezvous;fault detection;Delta operator;signal quantization;data? pecket loss
收稿日期 2020-03-15
作者簡(jiǎn)介劉瑞霞,女,博士,講師,研究方向?yàn)楹教炱鞴收显\斷、容錯(cuò)控制以及協(xié)同控制.ruixialiu@xupt.edu.cn