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  本文選題：非最小相位系統(tǒng) + 輸出軌跡跟蹤�。� 參考：《浙江大學(xué)》2017年碩士論文

【摘要】：非最小相位系統(tǒng)常見于工程應(yīng)用場合,如應(yīng)用于航天和生產(chǎn)制造領(lǐng)域的柔性機械臂,即是一種典型的非最小相位系統(tǒng)。由于不穩(wěn)定零動態(tài)的影響,非最小相位系統(tǒng)不存在因果穩(wěn)定的逆,因此常規(guī)反饋控制不能實現(xiàn)精確軌跡跟蹤。非因果穩(wěn)定逆控制是實現(xiàn)非最小相位系統(tǒng)軌跡準(zhǔn)確跟蹤的本質(zhì)方法。但由于其理論上需要有無限時長的預(yù)作用,不能直接應(yīng)用于實際系統(tǒng)操作;而且穩(wěn)定逆控制算法的有效性僅局限于雙曲非最小相位系統(tǒng)。綜合考慮實際應(yīng)用及跟蹤精度要求,本文針對雙曲和非雙曲非最小相位系統(tǒng),采用近似線性化方法,提出軌跡重定義的設(shè)計思路,以基函數(shù)形式重新定義期望輸出軌跡,實現(xiàn)被控系統(tǒng)在有限時間區(qū)間上的因果逆軌跡跟蹤,且系統(tǒng)實際輸出與理想期望軌跡的誤差滿足給定的跟蹤精度要求。本文取得的具體成果如下:(1)為解決非因果穩(wěn)定逆無限時長前驅(qū)動不適用于實際操作的問題,本文提出在有限時長區(qū)間內(nèi)重定義輸出軌跡取代無限時長前驅(qū)動過程,實現(xiàn)了被控系統(tǒng)由實際起始狀態(tài)到穩(wěn)定逆理想初始狀態(tài)的過渡。然后結(jié)合非因果穩(wěn)定逆的控制方法實現(xiàn)了非最小相位系統(tǒng)的準(zhǔn)確軌跡跟蹤控制。重定義的輸出軌跡采用指數(shù)基函數(shù)的形式,軌跡重定義過程使用一種優(yōu)化搜索算法尋找到最優(yōu)軌跡。在一個單連桿的柔性機械臂系統(tǒng)上進(jìn)行了新控制方法的仿真。結(jié)果說明了控制方法的有效性。(2)為設(shè)計適用于廣義非最小相位系統(tǒng)的軌跡跟蹤控制算法,同時提高軌跡跟蹤精度,本文提出了因果逆分段軌跡跟蹤控制方法。以指數(shù)基函數(shù)形式重新定義整段輸出軌跡,在盡可能近似期望輸出軌跡的條件下,設(shè)計控制器抵消掉非最小相位系統(tǒng)中不穩(wěn)定零點的影響,抑制發(fā)散。將輸出軌跡劃分為有限段逐段跟蹤,同時保證輸入信號、整段輸出軌跡及系統(tǒng)內(nèi)動態(tài)軌跡的連續(xù)性。將分段軌跡跟蹤控制算法應(yīng)用于實驗室懸掛式單連桿柔性臂系統(tǒng),仿真結(jié)果有效地證明了新方法能提高軌跡跟蹤精度。(3)實驗驗證,將所提出的分段軌跡跟蹤因果逆控制方法應(yīng)用于一個典型的非最小相位系統(tǒng)——柔性臂,通過最小二乘法辨識實際柔性臂系統(tǒng)模型,離線計算其控制輸入信號,反向輸入到實驗系統(tǒng),觀察記錄實際輸出信號,與期望輸出軌跡進(jìn)行對比,對結(jié)果進(jìn)行分析。實驗結(jié)果很好地證明了所設(shè)計控制方案的可行性。
[Abstract]:Non-minimum phase systems are commonly used in engineering applications, such as flexible manipulators used in aerospace and manufacturing fields, that is, a typical non-minimum phase system. Due to the effect of unstable zero dynamics, there is no causal stability inverse in the non-minimum phase system, so the conventional feedback control can not achieve accurate trajectory tracking. Non-causal stable inverse control is an essential method for accurate trajectory tracking of non-minimum phase systems. However, it can not be directly applied to practical system operation because of the need of pre-action with unlimited time in theory, and the effectiveness of the stability inverse control algorithm is limited to hyperbolic non-minimum phase systems. Considering the practical application and the requirement of tracking precision, this paper proposes a new design idea of trajectory redefinition for hyperbolic and non-hyperbolic non-minimum phase systems by using approximate linearization method. The desired output trajectory is redefined in the form of basis function. The causal inverse trajectory tracking of the controlled system in a finite time interval is realized, and the error between the actual output of the system and the ideal desired trajectory meets the given tracking accuracy requirements. The concrete results obtained in this paper are as follows: 1) in order to solve the problem that the non-causal stable inverse infinite time front drive is not suitable for practical operation, this paper proposes to redefine the output trajectory in the finite time interval to replace the infinite time front drive process. The transition from the actual initial state to the stable inverse ideal initial state of the controlled system is realized. Then the accurate trajectory tracking control of the non-minimum phase system is realized by using the non-causal stable inverse control method. The output trajectory is redefined in the form of exponential basis function. The trajectory redefinition process uses an optimal search algorithm to find the optimal trajectory. The simulation of the new control method is carried out on a single link flexible manipulator system. The results show the effectiveness of the control method. In order to design a trajectory tracking control algorithm for generalized non-minimum phase systems and improve the tracking accuracy, a causal inverse piecewise trajectory tracking control method is proposed in this paper. The whole output trajectory is redefined in the form of exponential basis function. Under the condition of approximating the desired output trajectory as much as possible, a controller is designed to counteract the influence of unstable zeros in the non-minimum phase system and to suppress divergence. The output trajectory is divided into finite segment by segment tracking, and the continuity of input signal, whole output track and dynamic trajectory in the system is ensured at the same time. The piecewise trajectory tracking control algorithm is applied to the single link flexible arm system in the laboratory. The simulation results show that the new method can improve the trajectory tracking accuracy. The proposed piecewise trajectory tracking causality inverse control method is applied to a typical non-minimum phase system-flexible arm. The actual flexible arm model is identified by the least square method, and the control input signal is calculated offline. The actual output signal is observed and recorded, and compared with the desired output trajectory, and the results are analyzed. The experimental results show the feasibility of the proposed control scheme.
【學(xué)位授予單位】：浙江大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：TP241

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本文編號：1951101