Axiomatic Design of Automotive Suspension Systems

This paper presents kinematic design methodology of a suspension system using Axiomatic Design (AD). AD is applied to typical three types of the front suspension systems: McPherson strut, double wishbone and multilink. Our study includes the analysis of the functional independencies of current suspension design configurations, which would add to the understanding of how various suspension hardpoints influence the suspension functional requirements (FRs). In addition, this paper also proposes sequential design orders in suspension kinematic design to satisfy all of the suspension FRs. Of the current kinematic designs, the multilink is a decoupled design, whereas McPherson strut and double wishbone are coupled designs. It is shown that a coupled design can be decoupled by applying the independence axiom. The design matrices formulated for the suspension systems indicate a specific design order to satisfy all FRs.     

Functional process adjustments to reduce No-Fault-Found product failures in service caused by in-tolerance faults

This paper presents a methodology to determine optimal process adjustments, which prevents manufacturing products from falling into in-tolerance fault regions (a subset of No-Fault-Found events) taking into consideration product and process adjustments constraints. The proposed methodology utilizes the design relationship between KPCs and KCCs to determine process functional adjustments. The methodology is illustrated through three product and process design configurations, uncoupled, decoupled and coupled.     

多轴CNC机床耦合轮廓误差补偿方法

介绍了CNC机床耦合轮廓误差补偿方法的原理及设计方法。首先分析了非耦合的轮廓控制系统,给出了轮廓误差的定义及算法,引入了耦合轮廓控制的概念。以两轴CNC机床为例,介绍了耦合轮廓控制系统的结构及设计方法。最后讨论了耦合轮廓控制的效果及需要进一步研究的问题。     

Designing direct printing process for improved piezoelectric micro-devices

The integrated use of thin film lead zirconate titanate (PZT) for micro-scale devices and transducers has been limited due to the coupled nature and process constraints of the current manufacturing processes for PZT. Direct printing of PZT would eliminate many of these couplings and constraints by providing controllable drop-on-demand deposition. This paper presents the design interaction analysis that leads to the development of an optimized drop-on-demand deposition process as a novel manufacturing process for PZT thin films. The uncoupled nature of this new deposition method enables the design of a new class of PZT micro-devices that has not been possible with current processing techniques.     

主动磁悬浮电主轴系统建模与控制参数分析

为实现磁悬浮电主轴的稳定悬浮运行并满足加工精度要求,通过对某型号主动磁悬浮电主轴的结构和控制原理进行研究,在忽略主轴转子磁化和磁漏等非线性因素影响的前提条件下,通过对主轴转子在磁悬浮轴承中的受力分析,建立了磁悬浮轴承的电磁支承力与轴承气隙偏移量及控制电流的表达式,对基于不完全微分PID控制的磁悬浮电主轴系统的临界转速与磁悬浮轴承的电磁刚度进行了定量研究,得到不同PID控制参数下,磁悬浮轴承支承刚度随涡动频率的变化曲线及固有频率随PID控制参数的变化曲线图。研究结果为磁悬浮电主轴控制系统进一步设计使用和分析优化提供了依据。     

Biomimetic design of an ultra-compact and light-weight soft muscle glove

Wearable robotic hand devices can support people doing hand-intensive tasks by reducing the physical stress and strain on the human hand. For the safety and comfort of the user, such a device should be compatible and inconspicuous. Based on these two requirements, this paper presents a biomimetic design of a wearable robotic hand device called soft muscle glove, aiming to restore the salient features and functionalities of the human hand. Inspired by the hand musculature, the soft structure of the glove contains strings, bands and shape memory alloy (SMA) spring actuators to replicate the functionalities of tendons, pulleys and muscles in the human hand. The low-mass and small-size SMA spring actuator allows an ultra-compact and light-weight design of the glove with high dexterity. The glove weighs in total 85.03 g inclusive of the actuators and microcontroller. The performance of the muscle glove was experimentally investigated through hand function tests. The experimental results suggest that the glove can achieve functional range of motion of the human hand and can perform a wide range of grasp types defined in grasp taxonomy. Moreover, the grasping performance of the muscle glove with coupled and uncoupled flexion of the finger joints was compared. The uncoupled control shows a better matching between the grasp posture and the objects form, contributing to more efficient force transmission. This confirms the benefits of the proposed highly biomimetic design.     

热处理炉温度智能测控专家系统的设计与实现

介绍了一种热处理炉温度智能测量控制专家系统,提出了温度测量数据融合技术和Ｆｕｚｚｙ＋ ＰＩＤ 控制技术相结合的设计方法。讨论了系统结构、知识表示、推理机、温度数据融合算法和智能控制方法。     

一种五自由度机电测控系统的设计与实现

文章提出了一种基于五自由度机电系统的测控系统设计方法，并从机械系统构成、测控系统结构及软硬件设计方面论述了系统实现技术。针对系统特定的功能要求，文章详细介绍了位姿组合测量和各位姿自由度控制的测控方法，并应用模块化设计和数据流分析方法进行软硬件设计。通过实验进行系统特性分析，得到运行参数指标。实验证明这种设计方法和实现技术合理可行。     

基于CORBA的DNC系统的实现

在分布式车间层控制系统开放式平台的基础上,采用面向对象方法对ＤＮＣ 系统进行详细功能分析和类层次设计,最终在Ｏｒｂｉｘ 平台上实现了三层客户服务器结构的ＤＮＣ系统应用程序。     

起重机油气悬挂系统刚度特性仿真与试验对比分析

为了验证液压油缸与蓄能器组成的油气悬挂系统刚性的非线性特性,将某起重机油气悬挂的液压系统作为研究对象,建立油气悬挂系统的刚度计算数学模型,并借助MATLAB作出了刚度变化曲线;在不同试验工况下进行刚度特性分析和比较,指出了理论模型与试验结果的差距,验证了油气悬挂系统的刚度变化趋势,对深入分析油气悬挂系统的其他性能具有借鉴意义。     

连通式油气悬挂系统刚度特性分析

建立了连通式油气悬挂系统的铅垂线刚度和侧倾角刚度的计算公式,分析了悬挂质量、蓄能器容积、初始充气压力,悬挂缸面积比以及悬挂缸的安装距等对刚度特性的影响,分析结果可以为连通式油气悬挂系统的设计提供依据。     

磁液双悬浮轴承单自由度支承系统解耦控制研究

磁液双悬浮轴承是以电磁悬浮为主,静压为辅的一种新型支承轴承,能够大幅度提高承载能力及刚度,适于中速重载的场合。由于液体静压系统特性为小间隙、强阻尼、正刚度、斥力型,而电磁悬浮系统特性为大气隙、弱阻尼、负刚度、吸力型,且两系统共同支承时相互耦合,互为干扰,大幅降低了支承系统的运行稳定性,因此本文拟研究磁液双悬浮轴承单自由度磁液两支承系统之间的耦合特性,揭示其耦合力的产生机理并设计解耦控制器。首先,本文介绍了磁液双悬浮轴承的结构特点、单自由度支承系统的受力形式以及控制调节机理。然后,建立了磁液双悬浮轴承单自由度支承系统的数学传递函数,揭示磁液两支承系统之间的耦合特征及影响规律。最后,设计了类前馈解耦控制器及对角阵解耦控制器,并通过Simulink模块对比分析了两种解耦控制器的解耦效果。研究表明：两种解耦控制器均能够有效减小单自由度磁液两支承系统间的耦合程度,但类前馈解耦控制器比对角阵解耦控制器具有更好的稳定性、准确性,更适用于磁液双悬浮轴承单自由度磁液两支承系统的解耦控制。本论文能够为磁液双悬浮系统的稳定控制提供理论参考。     

基于脚本语言的数控系统可定制界面的实现

本课题设计的数控系统可定制界面是以QT为平台,采用脚本程序定制界面的功能来实现.包括人机界面的设计与构建,QT界面加载器和脚本引擎的扩展,以及底层接口主程序的实现等;同时在QT图形组件类的基础上构建了数控系统专用的图形组件类库,是实现界面可定制性的基础.该方法充分利用了QT在GUI(Graphical User Interface,图形用户界面)设计方面的优势以及新增的支持脚本功能模块,使定制人机界面的过程变得简便快捷.     

金属板材成形中拉深损伤模拟的两种求解方法

讨论用数值模拟预测板材成形中发生拉深损伤破坏的两种不同的求解方法。第一种是采用完全耦合的弹塑性破坯模型的动力显式数值方法。基于状态参量的不可逆热力学过程 ,完全耦合的本构方程考虑各向同性强化和拉深。这些已引入有限元软件ABAQUS/E用于对金属成形的模拟。在数值技术方面 ,隐式积分方法被用来对本构方程的局部时间积分 ,动力显式技术用于求解总体平衡方程。第二种方案是采用简化的损伤模型的方法 ,被称为逆法 (InveseApprch)。I.A被限定在考虑各向同性强化和损伤的塑性全量理论基础上的简单的本构关系。做比例加载和临界损伤达到以后的损伤饱和假定 ,可以得到损伤演化方程的封闭解。这两种损伤模型在编程中的实施采用两种方式 :计算中考虑或不考虑损伤作用 ,也就是耦合的或非耦合的计算。文中给出一些算例来说明每种损伤模型的优点     

A grey prediction fuzzy controller for constant cutting force in turning

Constant force control is gradually becoming an important technique in the modern manufacturing process. Especially, constant cutting force control is a useful approach in increasing the metal removal rate and the tool life for turning systems. However, turning systems generally have non-linear with uncertainty dynamic characteristics. Designing a model-based controller for constant cutting force control is difficult because an accurate mathematical model in the turning system is hard to establish. Hence, this study employed a model-free fuzzy controller to control the turning system in order to achieve constant cutting force control. Nevertheless, the design of the traditional fuzzy controller (TFC) presents difficulties in finding control rules and selecting an appropriate membership function. To solve this problem, a grey-theory algorithm was introduced into the TFC to predict the next output error of the system and the error change, rather than the current output error of the system and the current error change, as input variables of the TFC. This design of the grey prediction fuzzy controller (GPFC) cannot only simplify the TFC design, but also achieves the desired result in TFC implementation. To confirm the applicability of the proposed intelligent controllers, this work retrofitted an old lathe for a turning system to evaluate the feasibility of constant cutting force control. The GPFC has better control performance in constant cutting force control than does the TFC, as verified in experimental results.     

基于逆系统的车用PMSM滑模矢量控制

为满足车用永磁同步电机 (PMSM)在快速响应的同时,在负载扰动以及参数变化下具有较强的鲁棒性,提出一种基于逆系统的PMSM滑模矢量控制。对强耦合、非线性的PMSM系统进行可逆性分析,基于逆系统将PMSM解耦成一阶线性转矩子系统和一阶线性定子转矩电流系统,以提高系统响应速度。利用线性连续函数代替传统滑模控制中的符号函数设计滑模控制器,以减小系统抖振、提高系统的鲁棒性与抗扰动能力。分析控制系统的稳定性与控制性能。结果表明：所提出的控制算法与传统PI控制相比响应迅速,在系统参数与负载变化时的鲁棒性显著提高。     

液压拉力试验机计算机辅助试验系统研究和实践

针对常规液压拉力试验机存在的不足,本文介绍一套采用工控机系统对拉力试验机进行改造的实例,详细介绍了系统的组成和软件系统设计方法。     

Designing a Turbine Blade Cooling System Using a Generalised Regression Genetic Algorithm

The design of a turbine blade cooling system is a multi-objective optimisation problem involving constraints and complex Interaction among its design variables. The aim of this paper is to develop a methodology to optimise this design using Evolutionary Computing techniques. This paper presents Generalised Regression Genetic Algorithm (GRGA) and the mathematical model of a real-life turbine blade cooling system. Even in the presence of variable interaction, the methodology identifies a number of good feasible designs from which one could be finally chosen based on designer's preferences. The research also demonstrates that GRGA is capable of optimising a real-life design.