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ON THE BOUNDEDNESS AND THE STABILITY RESULTS FOR THE SOLUTION OF CERTAIN FOURTH ORDER DIFFERENTIAL EQUATIONS VIA THE INTRINSIC METHOD 被引量:1
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作者 Cemil TUNC Aydin TIRYAKI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1996年第11期1039-1049,共11页
In this paper, we first present constructing a Lyapunov function for (1. 1) and then we show the asymptotic stability in the large of the trivial solution x=0 for case p≡ 0,and the boundedness result of the sol... In this paper, we first present constructing a Lyapunov function for (1. 1) and then we show the asymptotic stability in the large of the trivial solution x=0 for case p≡ 0,and the boundedness result of the solutions of (1 .1 ) for case p≠0. These results improve sveral well-known results. 展开更多
关键词 nonlinear differential equations of the fourth order Lyapunovfunction STABILITY BOUNDEDNESS intrinsic method
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Application of the Adomian Decomposition Method (ADM) for Solving the Singular Fourth-Order Parabolic Partial Differential Equation 被引量:1
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作者 Béyi Boukary Justin Loufouilou-Mouyedo +1 位作者 Joseph Bonazebi-Yindoula Gabriel Bissanga 《Journal of Applied Mathematics and Physics》 2018年第7期1476-1480,共5页
In this paper, the ADM method is used to construct the solution of the singular fourth-order partial differential equation.
关键词 SBA method SINGULAR fourth-order PARTIAL DIFFERENTIAL Equation
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An Adaptive Least-Squares Mixed Finite Element Method for Fourth Order Parabolic Problems
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作者 Ning Chen Haiming Gu 《Applied Mathematics》 2013年第4期675-679,共5页
A least-squares mixed finite element (LSMFE) method for the numerical solution of fourth order parabolic problems analyzed and developed in this paper. The Ciarlet-Raviart mixed finite element space is used to approxi... A least-squares mixed finite element (LSMFE) method for the numerical solution of fourth order parabolic problems analyzed and developed in this paper. The Ciarlet-Raviart mixed finite element space is used to approximate. The a posteriori error estimator which is needed in the adaptive refinement algorithm is proposed. The local evaluation of the least-squares functional serves as a posteriori error estimator. The posteriori errors are effectively estimated. The convergence of the adaptive least-squares mixed finite element method is proved. 展开更多
关键词 ADAPTIVE method LEAST-SQUARES Mixed Finite Element method fourth order Parabolic Problems LEAST-SQUARES Functional A POSTERIORI Error
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The Basic (<i>G'/G</i>)-Expansion Method for the Fourth Order Boussinesq Equation
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作者 Hasibun Naher Farah Aini Abdullah 《Applied Mathematics》 2012年第10期1144-1152,共9页
The (G'/G)-expansion method is simple and powerful mathematical tool for constructing traveling wave solutions of nonlinear evolution equations which arise in engineering sciences, mathematical physics and real ti... The (G'/G)-expansion method is simple and powerful mathematical tool for constructing traveling wave solutions of nonlinear evolution equations which arise in engineering sciences, mathematical physics and real time application fields. In this article, we have obtained exact traveling wave solutions of the nonlinear partial differential equation, namely, the fourth order Boussinesq equation involving parameters via the (G'/G)-expansion method. In this method, the general solution of the second order linear ordinary differential equation with constant coefficients is implemented. Further, the solitons and periodic solutions are described through three different families. In addition, some of obtained solutions are described in the figures with the aid of commercial software Maple. 展开更多
关键词 The (G'/G)-Expansion method the fourth order BOUSSINESQ Equation TRAVELING Wave Solutions Nonlinear Partial Differntial Equations
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THE SCHWARZ ALTERNATING METHOD FOR A FOURTH-ORDER VARIATIONAL INEQUALITY
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作者 蒋美群 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1994年第1期67-74,共8页
In this paper the Schwarz alternating method for a fourth-order elliptic variational inequality problem is considered by way of the equivalent form, and the geometric convergence is obtained on two subdomains.
关键词 SCHWARZ ALTERNATING method fourth-order VARIATIONAL INEQUALITY geometric convergence.
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New Fourth Order Iterative Methods Second Derivative Free
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作者 Osama Y. Ababneh 《Journal of Applied Mathematics and Physics》 2016年第3期519-523,共5页
In a recent paper, Noor and Khan [M. Aslam Noor, & W. A. Khan, (2012) New Iterative Methods for Solving Nonlinear Equation by Using Homotopy Perturbation Method, Applied Mathematics and Computation, 219, 3565-3574... In a recent paper, Noor and Khan [M. Aslam Noor, & W. A. Khan, (2012) New Iterative Methods for Solving Nonlinear Equation by Using Homotopy Perturbation Method, Applied Mathematics and Computation, 219, 3565-3574], suggested a fourth-order method for solving nonlinear equations. Per iteration in this method requires two evaluations of the function and two of its first derivatives;therefore, the efficiency index is 1.41421 as Newton’s method. In this paper, we modified this method and obtained a family of iterative methods for appropriate and suitable choice of the parameter. It should be noted that per iteration for the new methods requires two evaluations of the function and one evaluation of its first derivatives, so its efficiency index equals to 1.5874. Analysis of convergence shows that the methods are fourth-order. Several numerical examples are given to illustrate the performance of the presented methods. 展开更多
关键词 Newton’s method fourth-order Convergence Third-order Convergence Non-Linear Equations ROOT-FINDING Iterative method
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MULTIPLICITY RESULTS FOR FOURTH ORDER ELLIPTIC EQUATIONS OF KIRCHHOFF-TYPE 被引量:3
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作者 许丽萍 陈海波 《Acta Mathematica Scientia》 SCIE CSCD 2015年第5期1067-1076,共10页
In this paper, we concern with the following fourth order elliptic equations of Kirchhoff type {Δ^2u-(a+bfR^3|↓△u|^2dx)△u+V(x)u=f(x,u),x∈R^3, u∈H^2(R3),where a, b 〉 0 are constants and the primitive... In this paper, we concern with the following fourth order elliptic equations of Kirchhoff type {Δ^2u-(a+bfR^3|↓△u|^2dx)△u+V(x)u=f(x,u),x∈R^3, u∈H^2(R3),where a, b 〉 0 are constants and the primitive of the nonlinearity f is of superlinear growth near infinity in u and is also allowed to be sign-changing. By using variational methods, we establish the existence and multiplicity of solutions. Our conditions weaken the Ambrosetti- Rabinowitz type condition. 展开更多
关键词 fourth order elliptic equations of Kirchhoff type symmetric mountain pass theorem variational methods
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Superlinear Fourth-order Elliptic Problem without Ambrosetti and Rabinowitz Growth Condition 被引量:2
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作者 Wei Yuan-hong Chang Xiao-jun +1 位作者 L Yue Li Yong 《Communications in Mathematical Research》 CSCD 2013年第1期23-31,共9页
This paper deals with superlinear fourth-order elliptic problem under Navier boundary condition. By using the mountain pass theorem and suitable truncation, a multiplicity result is established for all λ〉 0 and some... This paper deals with superlinear fourth-order elliptic problem under Navier boundary condition. By using the mountain pass theorem and suitable truncation, a multiplicity result is established for all λ〉 0 and some previous result is extended. 展开更多
关键词 fourth-order elliptic problem variational method mountain pass theorem Navier boundary condition
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Existence of positive solutions for fourth order singular differential equations with Sturm-Liouville boundary conditions 被引量:1
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作者 Zhao Zengqin 《商丘师范学院学报》 CAS 2007年第12期1-8,共8页
By using the upper and lower solutions method and fixed point theory,we investigate a class of fourth-order singular differential equations with the Sturm-Liouville Boundary conditions.Some sufficient conditions are o... By using the upper and lower solutions method and fixed point theory,we investigate a class of fourth-order singular differential equations with the Sturm-Liouville Boundary conditions.Some sufficient conditions are obtained for the existence of C2[0,1] positive solutions and C3[0,1] positive solutions. 展开更多
关键词 存在性 四阶微分方程 减函数 Sturm-Liouville边值 正解
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High Accurate Fourth-Order Finite Difference Solutions of the Three Dimensional Poisson’s Equation in Cylindrical Coordinate 被引量:1
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作者 Alemayehu Shiferaw Ramesh Chand Mittal 《American Journal of Computational Mathematics》 2014年第2期73-86,共14页
In this work, by extending the method of Hockney into three dimensions, the Poisson’s equation in cylindrical coordinates system with the Dirichlet’s boundary conditions in a portion of a cylinder for is solved dire... In this work, by extending the method of Hockney into three dimensions, the Poisson’s equation in cylindrical coordinates system with the Dirichlet’s boundary conditions in a portion of a cylinder for is solved directly. The Poisson equation is approximated by fourth-order finite differences and the resulting large algebraic system of linear equations is treated systematically in order to get a block tri-diagonal system. The accuracy of this method is tested for some Poisson’s equations with known analytical solutions and the numerical results obtained show that the method produces accurate results. 展开更多
关键词 Poisson’s EQUATION Tri-Diagonal Matrix fourth-order FINITE DIFFERENCE APPROXIMATION Hockney’s method Thomas Algorithm
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Existence of Positive Solutions for A Fourth-order Boundary Value Problems with p-Laplacian Operators
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作者 WANG Wan-peng 《Chinese Quarterly Journal of Mathematics》 2018年第4期377-385,共9页
This paper investigates the existence of positive solutions for a fourth-order p-Laplacian nonlinear equation. We show that, under suitable conditions, there exists a positive number λ~*such that the above problem ha... This paper investigates the existence of positive solutions for a fourth-order p-Laplacian nonlinear equation. We show that, under suitable conditions, there exists a positive number λ~*such that the above problem has at least two positive solutions for 0 < λ < λ~* , at least one positive solution for λ = λ~* and no solution forλ > λ~* by using the upper and lower solutions method and fixed point theory. 展开更多
关键词 fourth-order P-LAPLACIAN POSITIVE SOLUTIONS UPPER and LOWER SOLUTIONS method Fixed point theory
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Existence of Infinitely Many High Energy Solutions for a Fourth-Order Kirchhoff Type Elliptic Equation in R<sup>3</sup>
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作者 Ting Xiao Canlin Gan Qiongfen Zhang 《Journal of Applied Mathematics and Physics》 2020年第8期1550-1559,共10页
In this paper, we consider the following fourth-order equation of Kirchhoff type<br /> <p> <img src="Edit_bcc9844d-7cbc-494d-90c4-d75364de5658.bmp" alt="" /> </p> <p> ... In this paper, we consider the following fourth-order equation of Kirchhoff type<br /> <p> <img src="Edit_bcc9844d-7cbc-494d-90c4-d75364de5658.bmp" alt="" /> </p> <p> where <i>a</i>, <i>b</i> > 0 are constants, 3 < <i>p</i> < 5, <i>V</i> ∈ <i>C</i> (R<sup>3</sup>, R);Δ<sup>2</sup>: = Δ (Δ) is the biharmonic operator. By using Symmetric Mountain Pass Theorem and variational methods, we prove that the above equation admits infinitely many high energy solutions under some sufficient assumptions on <i>V</i> (<i>x</i>). We make some assumptions on the potential <i>V</i> (<i>x</i>) to solve the difficulty of lack of compactness of the Sobolev embedding. Our results improve some related results in the literature. </p> 展开更多
关键词 fourth-order Kirchhoff Type Elliptic Equation Infinitely Many Solutions Symmetric Mountain Pass Theorem Variational methods
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某金属带式无级变速器振动仿真分析与多工况下试验验证
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作者 刘克铭 蔡琳滢 吴雪莹 《辽宁工程技术大学学报(自然科学版)》 CAS 北大核心 2024年第1期68-76,共9页
为分析某金属带式无级变速器(CVT)振动产生机理,采用集中参数法建立双级行星齿轮非线性扭转动力学模型,应用四阶龙格库塔方法进行动态响应求解,利用ADAMS软件进行动力学仿真,对动态响应进行验证,进行CVT振动台架试验测试。研究结果表明... 为分析某金属带式无级变速器(CVT)振动产生机理,采用集中参数法建立双级行星齿轮非线性扭转动力学模型,应用四阶龙格库塔方法进行动态响应求解,利用ADAMS软件进行动力学仿真,对动态响应进行验证,进行CVT振动台架试验测试。研究结果表明:四阶龙格库塔方法与ADAMS动态仿真得到的动态响应结果基本一致;台架试验结果表明前进挡转速为2500 r/min时,低速挡输入轴轴向位置的振动加速度最大为0.623 m/s^(2),转速为1000 r/min时,低速挡输入轴轴向位置的加速度最大为0.309 m/s^(2);倒挡工况下,转速为2500 r/min时,倒挡输入轴轴向位置的振动加速度最大为0.703 m/s^(2),转速1000 r/min时,倒挡输入轴轴向位置的加速度最大为0.504 m/s^(2);倒挡工况下的振动加速度幅值比前进挡高12.85%;倒挡阶次谱中54.4阶和108.8阶振动信号最为明显,挡位切换过程中双级行星齿轮啮合次数增多,啮合间隙是CVT在倒挡动力传递中振动增大的主要原因。 展开更多
关键词 无级变速器 振动分析 行星齿轮 阶次分析 四阶龙格库塔法 非线性动力学分析
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四阶椭圆型方程弱解的存在性 被引量:1
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作者 刘思童 梁波 《井冈山大学学报(自然科学版)》 2024年第1期1-7,共7页
针对四阶椭圆方程的不同形式,分别应用Lax-Milgram定理及变分法对两类四阶椭圆型方程进行研究。本文第一部分运用Lax-Milgram验证在Hilbert空间H^(2)上恒存在唯一的解u,使得H^(2)上的有界强制双线性型与H2上任一有界线性泛函相等。进而... 针对四阶椭圆方程的不同形式,分别应用Lax-Milgram定理及变分法对两类四阶椭圆型方程进行研究。本文第一部分运用Lax-Milgram验证在Hilbert空间H^(2)上恒存在唯一的解u,使得H^(2)上的有界强制双线性型与H2上任一有界线性泛函相等。进而证明出存在唯一弱解满足第一类含有一阶项的四阶椭圆型方程。第二部分运用变分方法解决另一类含有p次二阶项四阶椭圆型方程。在方法上,首先定义方程弱解,其次找出与方程相对应的泛函,进而将问题转化为求相应泛函的极值元,证明泛函极值元的存在性,最后证明弱解的唯一性。 展开更多
关键词 四阶椭圆型方程 Lax-Milgram定理 变分法 存在性 唯一性
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燃气发生器弹射特性数值仿真与试验研究
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作者 李宝星 孟豪龙 +1 位作者 梅开 王中 《计算机仿真》 2024年第8期25-30,285,共7页
为了研究燃气发生器弹射特性,基于改性双基固体推进剂装药结构和燃气发生器参数,建立了燃气底推弹射形式的数学模型,利用四阶龙格库塔法对数学模型进行求解,获得了燃气发生器弹射参数变化特性,结果表明:在常温条件下,载荷出简时的行程为... 为了研究燃气发生器弹射特性,基于改性双基固体推进剂装药结构和燃气发生器参数,建立了燃气底推弹射形式的数学模型,利用四阶龙格库塔法对数学模型进行求解,获得了燃气发生器弹射参数变化特性,结果表明:在常温条件下,载荷出简时的行程为7.7m,需要时间为0.53s,载荷出筒速度为31.1m/s,最大加速为81.7m/s^(2),满足弹射要求;同时,发现环境温度对燃气发生器弹射参数较大影响,随着环境温度增加,低压室压力峰值增加,载荷出筒时间缩短,出筒速度和最大过载增加;与常温弹射试验结果对比,低压力的压力峰值最大误差为5.2%,导弹载荷出筒速度最大误差为5.4%,表明所建立的燃气发生器弹射模型能够准确描述导弹载荷弹射参数特性。 展开更多
关键词 燃气发生器 弹射特性 四阶龙格库塔法 弹射参数 环境温度
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2维带色散4阶扩散方程的高精度紧致格式
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作者 王红玉 李冉冉 开依沙尔·热合曼 《安徽大学学报(自然科学版)》 CAS 北大核心 2024年第4期27-35,共9页
针对1,2维带色散4阶扩散方程提出了一种高精度紧致格式.首先采用局部1维化方法将2维问题转化为x,y方向的两个1维带色散4阶扩散方程,其次分别对3,4阶空间导数进行6阶紧致格式离散,把带色散4阶扩散方程转化为一个常微分方程组,再利用求解... 针对1,2维带色散4阶扩散方程提出了一种高精度紧致格式.首先采用局部1维化方法将2维问题转化为x,y方向的两个1维带色散4阶扩散方程,其次分别对3,4阶空间导数进行6阶紧致格式离散,把带色散4阶扩散方程转化为一个常微分方程组,再利用求解常微分方程组的L-稳定的Simpson方法构造时间3阶、空间6阶精度的数值格式,并证明该格式是绝对稳定的.通过数值实验和比较,验证论文格式的有效性. 展开更多
关键词 2维带色散4阶扩散方程 高精度紧致差分格式 CRANK-NICOLSON格式 局部1维化方法 L-稳定Simpson格式
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周期边界条件下四阶特征值问题的一种有效的Fourier谱逼近
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作者 何娅 安静 《数学物理学报(A辑)》 CSCD 北大核心 2024年第1期37-49,共13页
文章提出了周期边界条件下四阶特征值问题的一种有效的Fourier谱逼近方法.首先,根据周期边界条件引入了适当的Sobolev空间和相应的逼近空间,建立了原问题的一种弱形式及其离散格式,并推导了等价的算子形式.其次,定义了正交投影算子,并... 文章提出了周期边界条件下四阶特征值问题的一种有效的Fourier谱逼近方法.首先,根据周期边界条件引入了适当的Sobolev空间和相应的逼近空间,建立了原问题的一种弱形式及其离散格式,并推导了等价的算子形式.其次,定义了正交投影算子,并证明了其逼近性质,结合紧算子的谱理论证明了逼近特征值的误差估计.另外,构造了逼近空间中的一组基函数,推导了离散格式基于张量积的矩阵形式.最后,文章给出了一些数值算例,数值结果表明其算法是有效的和谱精度的. 展开更多
关键词 周期边界 四阶特征值问题 FOURIER谱方法 误差估计
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基于四阶累积量的改进传播算子DOA估计算法
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作者 窦慧晶 郭威 +1 位作者 谢东旭 郭宏亮 《北京工业大学学报》 CAS CSCD 北大核心 2024年第9期1061-1068,共8页
针对四阶累积量在多重信号分类(multiple signal classification, MUSIC)算法中计算复杂度高和在低信噪比情况下性能差的问题,提出一种去冗余后平均的四阶累积量传播算子算法(modified fourth-order cumulant propagator method, MFOC-... 针对四阶累积量在多重信号分类(multiple signal classification, MUSIC)算法中计算复杂度高和在低信噪比情况下性能差的问题,提出一种去冗余后平均的四阶累积量传播算子算法(modified fourth-order cumulant propagator method, MFOC-PM)。该算法通过引入传播算子算法线性地获得噪声子空间,避免了特征值分解造成的计算量,然后在保持四阶累积量阵列孔径扩展和抑制高斯噪声的优势下,通过求平均后去除的方法将四阶累积量中冗余的部分去除,降低了算法的复杂度。实验结果表明,所提算法显著减少了算法的计算量,可以实现角度的精确估计,在低信噪比的情况下表现良好,具有较好的实用价值。 展开更多
关键词 DOA估计 传播算子算法 四阶累积量 去冗余 阵列信号处理 阵列扩展
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椭圆域上二阶/四阶变系数问题有效的谱Galerkin逼近
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作者 田晓红 安静 《数学杂志》 2024年第3期269-282,共14页
本文提出了椭圆域上二阶/四阶变系数问题的一种有效的谱Galerkin逼近.首先,我们将原问题化为极坐标下的等价形式,并建立其弱形式及相应的离散格式.其次,针对二阶情形,我们证明了弱解和逼近解的存在唯一性及它们之间的误差估计.另外,根... 本文提出了椭圆域上二阶/四阶变系数问题的一种有效的谱Galerkin逼近.首先,我们将原问题化为极坐标下的等价形式,并建立其弱形式及相应的离散格式.其次,针对二阶情形,我们证明了弱解和逼近解的存在唯一性及它们之间的误差估计.另外,根据极条件和勒让得多项式的正交性,我们构造了一组有效的径向基函数,并在θ方向作截断的傅立叶展开,推导了离散格式等价的矩阵形式.最后,我们给出了大量的数值算例,数值结果表明了我们算法的收敛性和谱精度. 展开更多
关键词 二阶/四阶问题 谱Galerkin方法 误差分析 椭圆区域
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基于MATLAB的悬式机械臂提升动力学特性分析
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作者 周运康 何晓晖 +1 位作者 邵发明 张恒 《兵器装备工程学报》 CAS CSCD 北大核心 2024年第S01期396-401,共6页
提出一种悬式机械臂在预张紧和提升阶段的动力学模型。该模型考虑柔性梁、电机以及圆柱形有效载荷之间的动态耦合。采用Rayleigh-Ritz法,将能量代入拉格朗日方程,从而得到系统微分方程,使用MATLAB内置的四阶Runge-Kutta法对微分方程数... 提出一种悬式机械臂在预张紧和提升阶段的动力学模型。该模型考虑柔性梁、电机以及圆柱形有效载荷之间的动态耦合。采用Rayleigh-Ritz法,将能量代入拉格朗日方程,从而得到系统微分方程,使用MATLAB内置的四阶Runge-Kutta法对微分方程数值求解,并得到部分重要的参数曲线。数值解和曲线与其实际工作情况显示良好一致。 展开更多
关键词 悬式机械臂 预张紧阶段 提升阶段 动力学分析 四阶Runge-Kutta法
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