MULTIDISCIPLINARY ROBUST OPTIMIZATION DESIGN

Because uncertainty factors inevitably exist under multidisciplinary design environment, a hierarchical multidisciplinary robust optimization design based on response surface is proposed. The method constructs optimization model of subsystem level and system level to coordinate the coupling among subsystems, and also the response surface based on the artificial neural network is introduced to provide information for system level optimization tool to maintain the independence of subsystems, i.e. to realize multidisciplinary parallel design. The application case of electrical packaging demonstrates that reasonable robust optimum solution can be yielded and it is a potential and efficient multi-disciplinary robust optimization approach.     

模型驱动复杂机电系统软件与物理并行概念设计

并行设计是机电一体化系统概念设计的重要发展趋势,而软件作为复杂机电系统的重要组成部分,其早期设计通常与物理子系统串行开展,这极大限制了软件设计空间并导致严重的早期设计缺陷。为在复杂机电系统概念设计阶段实现软件与物理子系统的并行设计,提出了一种基于SysML的模型驱动软件与物理并行概念设计方法。将基于流的物理功能表示与基于数据/控制流图的软件功能表示相结合,提出了基于SysML的混合功能模型,通过该模型驱动软件与物理子系统设计的并行开展。在物理设计方面,基于功能效应匹配及时序规则模板实现带隐含时序约束的工作原理检索与筛选;在软件设计方面,基于分布式控制应用设计模式提出软件组件及其行为模型自动生成方法。最后,以移动机器人系统为例,展示了复杂机电系统软件与物理并行概念设计过程。     

机电一体化系统概念设计的基本原理

本文提出了机电一体化系统主要由广义执行机构子系统、信息处理及控制子系统、传感检测子系统组成。机电一体化系统从实质来说是现代化的机械系统。广义执行机构子系统由驱动元件和执行件（或执行机构）组成,用来传递动力、完成运动。信息处理及控制子系统由电子计算机来完成,传感检测子系统由传感器来实现,它们是现代机械系统重要的特征。由驱动元件和执行件（或执行机构）组成的广义执行机构子系统,是现代机械系统又一重要特征,构成了可控的传动和执行系统。由于三个子系统均以功能来划分,因此形成了较为合理的机电一体化系统的概念设计框架模型,有利于深入开展机电一体化的概念设计研究。     

工程机械车辆液压底盘二次调节模拟加载试验台的解耦控制

针对工程机械车辆液压底盘模拟试验台中驱动系统的转速控制子系统与加栽系统的转矩控制子系统的耦合问题，分析其对整套系统控制性能的影响。结合本试验台的特点，设计了一个基于单神经元PID控制的解耦网络，并给出了网络构造的全过程。实验以及仿真研究结果表明，通过在控制系统中加入特定的解耦网络，实现了驱动系统的转速控制子系统与加载系统的转矩控制子系统间的动态近似完全解耦，使两个子系统近似成为独立的控制系统，从而使系统的控制性能得到明显改善，为实际调试工作奠定了基础。     

甘蔗联合收割机机液速度控制系统的设计与仿真

甘蔗联合收割机在收割作业过程中,各作业机构间速度的合理匹配,对砍蔗质量、除杂效果以及蔗流堵塞等均有重要影响。基于联合收割机速度匹配的要求,提出了一种基于机械式速度跟踪器的机液速度反馈阀控系统,实现一个作业系统对另外一个作业系统的转速跟踪。运用AMESim与ADAMS软件对该系统进行联合仿真,结果表明：该系统适用于甘蔗联合收割机各子系统间转速的协调联动控制。转速跟踪误差与节流阀的流量增益有关,采用梯形槽节流阀口,速度跟踪误差小于5.24%,可适用于该系统,采用U形槽、三角形槽、L形槽形状的节流阀口,跟踪误差大,不适用于该系统。     

基于网络白板的概念设计系统研究

建立了一个基于网络白板的概念设计系统。该系统结合集中式和分布式的特点，采用B／S框架结构，为不同地理位置、不同学科的设计人员提供一个实时协同工作环境，以便共同完成概念设计阶段的活动和任务，能获取、共享及重用概念设计数据，有助于设计人员在设计早期进行创新思维。     

Decomposition method of complex optimization model based on global sensitivity analysis

The current research of the decomposition methods of complex optimization model is mostly based on the principle of disciplines, problems or components. However, numerous coupling variables will appear among the sub-models decomposed, thereby make the efficiency of decomposed optimization low and the effect poor. Though some collaborative optimization methods are proposed to process the coupling variables, there lacks the original strategy planning to reduce the coupling degree among the decomposed sub-models when we start decomposing a complex optimization model. Therefore, this paper proposes a decomposition method based on the global sensitivity information. In this method, the complex optimization model is decomposed based on the principle of minimizing the sensitivity sum between the design functions and design variables among different sub-models. The design functions and design variables, which are sensitive to each other, will be assigned to the same sub-models as much as possible to reduce the impacts to other sub-models caused by the changing of coupling variables in one sub-model. Two different collaborative optimization models of a gear reducer are built up separately in the multidisciplinary design optimization software iSIGHT, the optimized results turned out that the decomposition method proposed in this paper has less analysis times and increases the computational efficiency by 29.6%. This new decomposition method is also successfully applied in the complex optimization problem of hydraulic excavator working devices, which shows the proposed research can reduce the mutual coupling degree between sub-models. This research proposes a decomposition method based on the global sensitivity information, which makes the linkages least among sub-models after decomposition, and provides reference for decomposing complex optimization models and has practical engineering significance.     

Data driven uncertainty evaluation for complex engineered system design

Complex engineered systems are often difficult to analyze and design due to the tangled interdependencies among their subsystems and components. Conventional design methods often need exact modeling or accurate structure decomposition, which limits their practical application. The rapid expansion of data makes utilizing data to guide and improve system design indispensable in practical engineering. In this paper, a data driven uncertainty evaluation approach is proposed to support the design of complex engineered systems. The core of the approach is a data-mining based uncertainty evaluation method that predicts the uncertainty level of a specific system design by means of analyzing association relations along different system attributes and synthesizing the information entropy of the covered attribute areas, and a quantitative measure of system uncertainty can be obtained accordingly. Monte Carlo simulation is introduced to get the uncertainty extrema, and the possible data distributions under different situations is discussed in detail. The uncertainty values can be normalized using the simulation results and the values can be used to evaluate different system designs. A prototype system is established, and two case studies have been carried out. The case of an inverted pendulum system validates the effectiveness of the proposed method, and the case of an oil sump design shows the practicability when two or more design plans need to be compared. This research can be used to evaluate the uncertainty of complex engineered systems completely relying on data, and is ideally suited for plan selection and performance analysis in system design.     

Design Change Model for Effective Scheduling Change Propagation Paths

Changes in requirements may result in the increasing of product development project cost and lead time,therefore,it is important to understand how requirement changes propagate in the design of complex product systems and be able to select best options to guide design.Currently,a most approach for design change is lack of take the multi-disciplinary coupling relationships and the number of parameters into account integrally.A new design change model is presented to systematically analyze and search change propagation paths.Firstly,a PDS-Behavior-Structure-based design change model is established to describe requirement changes causing the design change propagation in behavior and structure domains.Secondly,a multi-disciplinary oriented behavior matrix is utilized to support change propagation analysis of complex product systems,and the interaction relationships of the matrix elements are used to obtain an initial set of change paths.Finally,a rough set-based propagation space reducing tool is developed to assist in narrowing change propagation paths by computing the importance of the design change parameters.The proposed new design change model and its associated tools have been demonstrated by the scheduling change propagation paths of high speed train’s bogie to show its feasibility and effectiveness.This model is not only supportive to response quickly to diversified market requirements,but also helpful to satisfy customer requirements and reduce product development lead time.The proposed new design change model can be applied in a wide range of engineering systems design with improved efficiency.     

复杂工程系统多学科设计优化集成环境研究

复杂工程系统的设计是一个多学科互相适应的系统过程,是一个多学科交叉综合设计优化的多目标决策过程。针对复杂工程系统设计过程,提出了复杂工程系统多学科设计优化集成环境模型,作为提高设计自动化的平台,给出了集成环境的体系结构和技术结构方案,定义了集成环境优化设计的流程;详细说明了工程系统多学科设计优化方法、智能产品模型两项关键技术。最后对集成环境的实施和验证做了相应的阐述。     

基于Adomian分解方法的暂态稳定并行仿真研究

针对目前大规模电力系统难以实现快速实时仿真的问题,提出了一种基于Adomian分解方法的暂态稳定仿真并行算法。首先,在考虑节点权重的同时,采用METIS将大系统拆分成若干子系统,然后采用波形松弛方法对系统进行并行求解。为加速各子系统的迭代过程,所有状态变量经过隐式梯形积分格式差分化后,采用基于Adomian分解的迭代算法配合非诚实牛顿算法进行了求解;为了进一步提高波形松弛法的整体收敛性,同时还使用了窗口方法、预处理方法与波形预测方法;最后,采用2 383节点和12685节点两个算例进行了测试,发电机采用复杂模型,同时考虑励磁调速系统,并通过共享内存的并行环境加以实现。测试研究结果表明,上述算法可以取得较为理想的收敛速度和并行加速比,同时实现了上万节点的超实时仿真。     

工序关联下考虑主体心理感知的复杂产品设计变更决策优化

基于设计结构矩阵的工序耦合分析难以有效地解决复杂产品设计变更中工序关联解耦、设计再调整、设计资源再配置等多主体决策优化问题,且将主体作为完全理性行为人的决策优化理论与具体实践亦偏差较大.对此,提出了工序关联下考虑主体心理感知的复杂产品设计变更决策优化方法.运用前景理论构建以设计主体对工序重复执行和设计变更延期心理感知扰...     

微机电系统多学科设计优化

多学科设计优化是一种针对于涵盖多个学科领域的复杂系统进行设计优化的方法,强调各子学科系统在独自设计优化的基础上的相互之间的并行协作。鉴于微机电系统(Micro electro mechanical systems,MEMS)设计中存在多学科交叉耦合等问题,将多学科优化设计方法引入到MEMS的设计中,研究分析MEMS本身的多学科特性和设计现状,建立面向MEMS的多学科设计优化系统(Micro electro mechanical multidisciplinary design optimization system,MMDOS),提出四种多学科设计优化方法,对提升MEMS的设计水平和产品质量具有积极意义。     

复杂机械产品虚拟样机多学科设计优化研究

为了以尽可能高的效率求得复杂机械产品虚拟样机尽可能优的设计方案,提出了一种将多学科设计优化方法与计算机仿真分析相结合的虚拟样机优化设计模式。通过将多学科设计优化方法应用于虚拟样机的并行设计过程,构建了虚拟样机的多学科设计优化集成平台,由多学科优化来驱动设计分析进程,形成虚拟样机集成的闭环自动迭代优化设计过程。针对汽车设计,给出了虚拟样机多学科设计优化的集成分析流程,同时利用虚拟样机的动态特性显示,直观地表现出复杂产品多学科设计优化过程中设计方案的变化。     

机电控制系统抗干扰分层设计

日益严格的电磁兼容法规和用户对可靠性的苛刻要求使得机电系统的电磁兼容问题日益突出,良好的电磁兼容来自于设计而不是测试,本文根据控制系统设计过程,提出了机电控制系统分层抗干扰设计方法。     

Robust Collaborative Optimization Method Based on Dual-response Surface

A novel method for robust collaborative design of complex products based on dual-response surface (DRS-RCO) is proposed to solve multidisciplinary design optimization (MDO) problems under uncertainty. Collaborative optimization (CO) which decomposes the whole system into a double-level nonlinear optimization problem is widely Accepted as an efficient method to solve MDO problems. In order to improve the quality of complex product in design process, robust collaborative optimization (RCO) is developed to solve those problems under uncertain conditions. RCO does opfmiTation on the linear sum of mean and standard deviation of objective function and gets an optimal solution with high robustnmess. Response surfaces method is an important way to do approximation in robust design. DRS-RCO is an improved RCO method in which dual-response surface replaces system uncertainty analysis module of CO. The dual-response surface is the approximate model of mean and standard deviation of objective function respectively. In DRS-RCO, All the information of subsystems is included in dual-response surfaces. As an additional item, the standard deviation of objective function is added to the subsystem optimization. This item guarantee both the mean and standard deviation of this subsystem is reaching the minima at the same time. Finally, a test problem with two coupled subsystems is conducted to verify the feasibility and effectiveness of DRS-RCO.     

汽车乘员舱安全性与舒适性多学科设计优化

概念设计阶段汽车乘员舱的安全性和舒适性设计是关键任务,两者具有耦合效应,将多学科设计优化运用到乘员舱的设计中实现两个学科的并行设计。针对某款车的乘员舱布置,在该车100%正面碰撞试验基础上,通过乘员损伤分析软件建立该车的正面碰撞乘员约束系统模型并对模型进行验证用于评估其安全性;同时也基于关节强度的概念建立乘员舒适性模型。将多学科设计优化运用到乘员舱的设计中,避免了传统设计方法对安全性和舒适性的单独优化,实现了两个学科的并行设计,缩短了开发周期,最大化了乘员舱的整体性能。为提高计算效率,通过试验设计构建乘员约束系统的Kriging近似模型用于代替仿真模型。结果表明,该方法在较好地满足乘员安全性的同时提高了乘员的乘坐舒适性,在乘员舱布置方面具有较强的工程实用性。     

机电一体化系统概念设计过程模型的研究

主要研究了机电一体化系统的概念设计。通过对机电一体化系统的组成的新认识和它的概念设计特点的分析 ,提出了基于功能 行为 结构模型的机电一体化系统概念设计过程模型。它将有助于推动由思维模型向计算模型的转换 ,实现计算机辅助概念设计的目标。     

农业装载机械的多领域仿真研究及优化

文章提出农业装载机械多领域统一仿真优化模型及其优化设计策略解决农业装载机械设计问题,基于知识导航的方法建立了农业装载机械多领域系统模型,通过全局综合满意度尽量大寻优策略协调得到最优解,采用基于知识的农业装载机械设计仿真过程管理技术对设计过程的数据,项目进行管理。开发了农业装载机械多领域仿真优化设计平台,并以多功能装载机仿真优化设计过程验证论文的正确性和有效性,对农业机械领域的数字化设计有参考价值。     

无轴承异步电机的非线性动态解耦控制

针对无轴承异步电机多变量、非线性、强耦合的特点,提出一种基于支持向量机α阶逆系统理论的非线性动态解耦控制策略。将通过支持向量机回归方法辨识出的无轴承异步电机逆系统串接在原系统之前,构成伪线性复合系统,实现整个系统的线性化。最后根据线性系统理论进行了系统综合。仿真和实验研究表明,支持向量机α阶逆系统方法能够实现无轴承异步电机悬浮力和旋转力之间的动态解耦,控制系统具有良好的动静态性能。