共查询到18条相似文献,搜索用时 187 毫秒
1.
针对车辆主动悬架线性二次型调节器(Linear Quadratic Regulator, LQR)控制中权重系数的取值具有主观性,且适应度较低的问题,提出使用粒子群优化(PSO)算法优化LQR控制器,使LQR控制器的权重矩阵得到最优结果。为验证此方法的有效性,以汽车主动悬架作为被控对象,设计了PSO算法优化LQR控制器,利用PSO算法的全局搜索能力,以主动悬架的性能指标作为目标函数对权重矩阵进行优化设计,以提高LQR控制器的设计效率和性能。通过仿真对比了LQR控制的主动悬架、固定权值PSO算法优化后的LQR控制的主动悬架和基于线性递减权值PSO算法优化LQR控制主动悬架的各项性能参数,并且针对固定权值PSO算法收敛速度慢的特点,进行优化,确定使用线性递减权值PSO算法可以提高收敛速度。最终实验结果表明基于固定权值PSO算法优化后的LQR相较于单纯LQR控制的主动悬架,其车身垂向加速度、悬架动行程及轮胎动位移这3个性能指标得到降低;基于线性递减权值PSO算法优化后的LQR控制的主动悬架的各项性能指标在固定权值PSO算法优化的基础上,可再次优化车身垂向加速度、悬架动行程及轮胎动位移这3个性... 相似文献
2.
3.
4.
优化PID与神经PID控制主动悬架的性能对比研究 总被引:1,自引:0,他引:1
为主动悬架选择一种更可行的控制方法,对PID与神经PID控制主动悬架进行了优化后的性能对比研究。基于1/4车二自由度主动悬架模型,利用遗传算法以悬架二次型性能指标为目标函数,分别对PID控制主动悬架的增益系数与神经PID控制主动悬架的初始权值和学习效率进行了优化。优化结果显示:优化后的PID控制主动悬架的综合性能较神经PID控制主动悬架略优。出现上述结果的原因在于:当神经PID控制主动悬架的学习效率等于零时则退化成PID控制主动悬架,学习效率不等于零则导致神经PID控制主动悬架的实时PID权值偏离了最优的PID权值。此外凸块路面输入下的仿真也显示优化PID的鲁棒性也略优于优化神经PID。因此,选择算法较复杂的神经PID对主动悬架进行控制是没有必要的。 相似文献
5.
针对车辆主动悬架线性二次最优控制存在的权值系数确定问题,提出了一种结合主客观性能评价的权值系数选择方法---层次分析-三代遗传算法。利用层次分析法确定变量范围,以6个主动控制悬架性能指标为目标函数,利用三代遗传算法进行多目标优化并以控制力作为限制条件筛选出最优解。以半车模型为例,结合前轮预瞄信息与卡尔曼估计器估计的状态变量,设计预瞄最优控制器,并采用虚拟激励法直接在频域范围内进行求解。仿真结果表明,所提出的控制策略可改善车辆的乘坐舒适性。 相似文献
6.
7.
8.
9.
10.
基于序关系分析法(G1法)进行了车辆主动悬架线性二次型高斯(Linear Quadratic Gaussian,LQG)最优控制器设计.首先对单轮车辆的主被动悬架进行数学建模,确定了系统输入信号模型;其次运用动力学知识建立了系统运动状态空间方程,并结合最优控制理论完成了最优线性控制器设计;结合序关系分析法确定了主被动悬架各性能指标系数的加权系数;最后在Simulink中对模型进行了对比仿真.仿真结果表明,在给定路况下,运用序关系分析法确定合适的权重值,优化了车身加速度、悬架动行程和轮胎动位移,较好地改善了车辆的综合性能,并且将主动控制力控制在了要求范围内. 相似文献
11.
The Linear Quadratic Gaussian (LQG) algorithm has been used to control the JPL's beam wave-guide, and 70-m antennas. This algorithm significantly improves tracking precision in a wind disturbed environment. Based on this algorithm and the implementation experience a Matlab based Graphical User Interface (GUI) was developed to design the LQG controllers applicable to antennas and radiotelescopes. The GUI is described in this paper. It consists of two parts the basic LQG design and the fine-tuning of the basic design using a constrained optimization algorithm. The presented GUI was developed to simplify the design process, to make the design process user-friendly, and to enable design of an LQG controller for one with a limited control engineering background. The user is asked to manipulate the GUI sliders and radio buttons to watch the antenna performance. Simple rules are given at the GUI display. 相似文献
12.
This paper aims to obtain the optimal composite slender beam design for a rotor blade. The cross-sectional dimensions are considered as design variables. The objective is to optimize the box beam to attain a target matrix of stiffness values and maximum elastic coupling. The optimization process is performed using a genetic algorithm (GA), associated with a variational asymptotic method for the structural analysis. The stiffness control of arbitrary, complex section under some design condition is performed in composite beam where the geometrically nonlinear characteristic of the structure is considered. The objective function is defined as the weight, strength and fatigue life. The laminate thicknesses are to be determined optimally by defining a design index comprising a weighted average of the objective functions and determining the minimum. 相似文献
13.
This paper proposes a new method for obtaining a linear quadratic Gaussian (LQG) benchmark in terms of the variances of process input and output from closed-loop data, for assessing the controller performance. LQG benchmark has been proposed in the literature to assess controller performance since the LQG tradeoff curve represents the limit of performance in terms of input and output variances. However, an explicit parametric model is required to calculate the LQG benchmark. In this work, we propose a data driven subspace approach to calculate the LQG benchmark under closed-loop conditions with certain external excitations. The optimal LQG-benchmark variances are obtained directly from the subspace matrices corresponding to the deterministic inputs and the stochastic inputs, which are identified using closed-loop data with setpoint excitation. These variances are used for assessing the controller performance. The method proposed in this paper is applicable to both univariate and multivariate systems. Profit analysis for the implementation of feedforward control to the existing feedback-only control system is also analyzed under the optimal LQG performance framework. The proposed method is illustrated through a simulation example and an application on a pilot scale process. 相似文献
14.
基于遗传算法的LQ控制器的权值优化 总被引:5,自引:0,他引:5
线性二次型最优调节器及线性二次型高斯问题,通称LQ问题,是最优控制在民用工业中应用最广的算法。LQ问题的解,最终归结为求解Riccati方程,而方程解的有效性,很大程度上又依赖于两个权矩阵Q阵和R阵的选择,如何选择Q阵和R阵以保证实现控制目标最优一直为控制界所注。本文提出以遗传算法来达到实现全局寻优的目的,得到较满意的结果。 相似文献
15.
一种计算步行式底盘局部结构载荷的优化方法 总被引:3,自引:0,他引:3
为确定步行式底盘局部结构在作业时的最大受力状态,对底盘结构进行强度设计,建立底盘和局部受力结构在作业状态下包含所有位置自由度参数的力学分析模型,提出一种基于响应面法求解底盘局部结构载荷的优化分析模型。用两级优化模型对局部结构的最大受力状态进行优化:第1级优化模型用逐步二次规划法找到局部结构在给定位置参数下的最大受力状态,然后通过正交试验设计构造出局部结构界面最大受力状态与位置参数之间的响应面函数;第2级优化模型用遗传算法求解响应面函数的最大值,并通过二分法不断缩小位置参数的搜索空间,提高响应面函数的逼近水平。研究表明,该优化方法是解决复杂结构系统中多变量优化问题的有效手段,并为步行式机构设计提供理论依据。 相似文献
16.
高精度的PID控制算法对汽车底盘测功机运行过程中的实时控制具有重要的作用,为此提出了一种面向汽车底盘测功机的BP+RNN变速积分PID算法控制系统:引入RNN加入时序性因素整定积分项参数,利用BP神经网络整定比例项与微分项参数,使用变速积分PID算法作为其控制方法。实验结果表明该PID控制系统不但能够快速整定PID参数(10个控制周期以内),同时还保证控制超调量在目标值的2%以内。与传统的增量式PID算法控制相比,BP+RNN变速积分PID算法控制系统的参数整定简单快速,消除了静态误差,使汽车底盘测功机的控制性能得到大幅改善。 相似文献
17.
To improve the dynamic performance and reduce the weight of the planet carrier in wind turbine gearbox, a multi-objective optimization method, which is driven by the maximum deformation, the maximum stress and the minimum mass of the studied part, is proposed by combining the response surface method and genetic algorithms in this paper. Firstly, the design points’ distribution for the design variables of the planet carrier is established with the central composite design (CCD) method. Then, based on the computing results of finite element analysis (FEA), the response surface analysis is conducted to find out the proper sets of design variable values. And a multi-objective genetic algorithm (MOGA) is applied to determine the direction of optimization. As well, this method is applied to design and optimize the planet carrier in a 1.5 MW wind turbine gearbox, the results of which are validated by an experimental modal test. Compared with the original design, the mass and the stress of the optimized planet carrier are respectively reduced by 9.3% and 40%. Consequently, the cost of planet carrier is greatly reduced and its stability is also improved. 相似文献
18.
在进行系列化产品结构设计及其优化设计时,将参数化设计引入到有限元结构分析中,实现结构参数快速调整,自动生成分析模型并完成结构分析过程,可优化产品结构、缩减产品设计周期。本文利用有限元分析软件ANSYS提供的APDL语言,实现了汽车起重机车架不同截面的有限元建模和分析的参数化,避免了大量重复的有限元建模与前、后处理操作,明显提高了产品设计效率。 相似文献