【摘要】：本文研究了典型柔性鉸鏈的疲勞性能以及柔順機(jī)構(gòu)的損傷識別。柔順機(jī)構(gòu)的運(yùn)動(dòng)是通過其柔性構(gòu)件的變形來實(shí)現(xiàn)的。對一些柔順機(jī)構(gòu)來說,所需的動(dòng)作可能只發(fā)生一次,因此靜態(tài)失效理論就足以分析這類機(jī)構(gòu)了。然而在設(shè)計(jì)時(shí)通常要求機(jī)構(gòu)能進(jìn)行多次運(yùn)動(dòng),可能是上萬次的往復(fù)循環(huán),甚至是”無限”壽命。這種反復(fù)加載會(huì)使構(gòu)件中產(chǎn)生交變應(yīng)力,在應(yīng)力遠(yuǎn)低于產(chǎn)生靜態(tài)失效的應(yīng)力值時(shí)就可能發(fā)生疲勞失效。因此,通過理論和實(shí)驗(yàn)來確定柔順機(jī)構(gòu)的疲勞失效是非常重要的。對于柔順機(jī)構(gòu)這種復(fù)雜并且成本高的機(jī)構(gòu),重復(fù)的疲勞實(shí)驗(yàn)非常困難。因此,以典型柔性鉸鏈的疲勞分析為基礎(chǔ),建立基于特征參數(shù)分解的柔順機(jī)構(gòu)的損傷識別方法,可以預(yù)測柔順機(jī)構(gòu)的壽命。這對于柔順機(jī)構(gòu)的研究和發(fā)展具有重要意義。 本文分析了直圓型和葉型兩種典型柔性鉸鏈的疲勞性能。利用基于臨界平面法的疲勞準(zhǔn)則,建立了柔性鉸鏈疲勞分析模型。疲勞實(shí)驗(yàn)的結(jié)果證明了模型的正確性。通過疲勞實(shí)驗(yàn)給出了柔性鉸鏈的壽命曲線以及考慮可靠性的壽命曲線簇。最后擬合出了柔性鉸鏈疲勞壽命經(jīng)驗(yàn)公式,分析了尺寸參數(shù)對鉸鏈疲勞壽命的影響。結(jié)果表明,尺寸參數(shù)對鉸鏈的疲勞壽命有較大影響,必須根據(jù)不同的壽命要求選擇合適的尺寸參數(shù)。 基于特征參數(shù)分解法,建立了柔順機(jī)構(gòu)的損傷識別方法。算例結(jié)果證明了方法的有效性。結(jié)果表明,本方法可以準(zhǔn)確的識別損傷的單元個(gè)數(shù)、位置以及損傷程度,并且適用于多損傷以及大損傷情況。
[Abstract]:The fatigue performance of typical flexure hinge and damage identification of compliant mechanism are studied in this paper. The motion of compliant mechanism is realized by the deformation of its flexible member. For some compliant mechanisms, the required action may occur only once, so the static failure theory is sufficient to analyze such mechanisms. However, the mechanism is usually required to move many times, possibly tens of thousands of cycles, or even "infinite" life. This kind of repeated loading will result in alternating stress in the member, and fatigue failure may occur when the stress is far below the value of the stress that produces static failure. Therefore, it is very important to determine fatigue failure of compliant mechanism through theory and experiment. Repeated fatigue tests are very difficult for a complex and high cost compliant mechanism. Therefore, based on the fatigue analysis of typical flexure hinge, the damage identification method of compliant mechanism based on characteristic parameter decomposition is established, which can predict the life of compliant mechanism. This is of great significance to the research and development of compliant mechanism. In this paper, the fatigue properties of two typical flexure hinges, straight shape and blade shape, are analyzed. The fatigue analysis model of flexure hinge is established by using the fatigue criterion based on critical plane method. The fatigue test results show that the model is correct. The life curve of flexure hinge and the life curve cluster considering reliability are given by fatigue experiment. Finally, the empirical formula of fatigue life of flexure hinge is fitted, and the influence of dimension parameters on fatigue life of hinge is analyzed. The results show that the size parameters have great influence on the fatigue life of the hinge, and the appropriate dimension parameters must be selected according to the different life requirements. Based on the characteristic parameter decomposition method, the damage identification method of compliant mechanism is established. The numerical results show that the method is effective. The results show that the method can accurately identify the number, location and degree of damage, and is suitable for multiple and large damage cases.
【學(xué)位授予單位】：華南理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2011
【分類號】：TH112

【引證文獻(xiàn)】

相關(guān)期刊論文 前1條

1 張憲民;汪啟亮;;柔順機(jī)構(gòu)疲勞可靠性及損傷識別研究進(jìn)展[J];華南理工大學(xué)學(xué)報(bào)(自然科學(xué)版);2012年10期

，

本文編號：2368323