高速皮革裁剪机伺服控制系统多目标优化

针对皮革裁剪机迫切向高速化方向发展的需求,首先提出了皮革裁剪机伺服系统三环PID控制策略,建立了伺服进给系统的数学模型和控制系统Simulink仿真模型。以调节时间和ISE性能指标为优化目标,以超调量和控制器输出的峰值为约束条件,建立皮革裁剪机速度PI控制器的多目标优化模型。在iSIGHT环境下,采用带精英策略的非支配排序遗传算法NSGA-II对多目标优化模型进行求解,在生成的Pareto最优解集的基础上排序选出最优解。将优化结果与传统遗传算法比较,结果表明,采用多目标优化方法获得了更加优良的动态特性。对进一步提高高速皮革裁剪机的裁剪速度具有很好的工程实用价值。     

基于BP-NSGA的注塑参数多目标智能优化设计

为获得成型性能最优的注塑参数设计方案,提出了基于BP神经网络和非支配排序遗传算法的注塑参数多目标优化方法。将注塑模结构尺寸参数和注塑工艺参数作为待优化的设计变量,建立了以高质量、低成本、高效率为优化目标的注塑参数优化设计模型。基于非支配排序遗传算法获取给定参数范围内的所有Pareto最优解,并通过建立多输入和多输出的BP神经网络来快速获得非支配排序遗传算法优化进程中所有个体的适应度值。开发了基于BP神经网络与非支配排序遗传算法集成的注塑参数智能优化设计系统,并通过鼠标注塑参数设计实例,验证了其适用性和有效性。     

单神经元与IPSO的双电机同步控制研究

为了满足机床、起重、造纸等行业中对多(双)电机同步控制系统的需要,针对现有双电机系统在启动和有负载扰动时会产生较大的转速同步误差从而易发生差速震荡的缺点,提出了一种新的转速同步控制方法.首先设计了改进时间与绝对误差乘积的积分评价指标(IITAE)下的改进粒子群算法(IPSO),对系统的控制器参数进行整定;然后从系统整体同步性能的角度出发,利用单神经元算法的交叉耦合控制器对双电机系统的同步性进行实时控制.通过simulink仿真和dSPACE实验对比结果表明:所提控制方法大大增强了双电机系统的转速同步性、鲁棒性和动态跟踪性能.     

非支配排序自适应遗传算法的车削优化

针对车削切削参数的优化提出了一种单目标非支配排序自适应遗传算法(SONSAGA),算法保留了NSGA-II的精英保留策略、快速非支配排序优点,克服了NSGA-II中取值边界附近多个无法消除的支配点现象。车削实例计算结果获得优于已发表文献的优选值,证明单目标非支配排序的自适应遗传算法用于车削用量参数的优化是有效的。SONSAGA算法设置参数少,包括相对变化量、种群规模、最大遗传代数,能自动调节最大遗传代数以及自适应地得到满足给定相对变化量的优选值,为车削用量优化提出了新思路。     

多目标炼钢—连铸生产调度的改进带精英策略的快速非支配排序遗传算法

针对炼钢连铸调度的特殊工艺要求,在考虑炉机匹配原则和多重精炼的情况下,建立了以炉机匹配度、炉次间等待时间、浇次的开浇提前/拖期时间为评价指标的多目标约束满足优化模型,并针对其多目标特征,提出一种基于自适应网格法的择优策略来改进带精英策略的快速非支配排序遗传算法,有效克服了使用传统Pareto支配法择优策略在解决离散问题时容易丢失有用信息的缺陷。基于多种规模的实际生产数据进行仿真实验,结果表明所提算法在收敛性、最优解集多样性和计算效率方面优于传统带精英策略的快速非支配排序遗传算法。     

基于改进引力搜索算法的铣削加工参数低碳建模及优化

针对数控机床铣削加工特点,考虑刀具寿命、加工表面质量、切削速率和铣床工艺性能等条件,以铣削加工过程中的单位体积碳排放、单位体积生产成本和加工时间为目标,以切削速率、每齿进给量和切削宽度三参数为优化变量,建立了铣削加工参数多目标优化模型,并提出了一种改进的非支配排序引力搜索算法对该多目标模型进行求解。在所提出算法中采用精英保留策略和位置更新回退操作,引导群体质点向真实Pareto最优解集区域靠近。在遗传算法的交叉操作启发下,提出精英精英交叉策略和精英非精英交叉策略,增加了群体多样性。最后与原始非支配排序引力搜索算法和教学优化算法进行对比,验证了所提改进算法的优越性和可行性。采用灰色关联度法在获得的Pareto最优解集中选择满意解,为面向绿色制造的切削参数优化提供了一种新的思路。     

基于自适应遗传算法的异步电机矢量控制参数优化与仿真

自动控制领域中PID参数的整定是一个极其重要的问题。为解决工程人员凭经验对异步电机控制器参数整定难寻到最优解的问题,将速度误差积分型作为目标函数,采用惩罚措施,利用自适应遗传算法对异步电机速度控制器的参数进行优化、仿真,并与利用常规PID参数整定获得的速度曲线相对比,实验结果表明,用自适应遗传算法优化的参数,可以提高系统的控制精度、动态性能。     

基于遗传算法与频率法校正的直线电机位置控制研究

针对直线电机的工作原理,采用PID控制算法与频率法对电机的位置进行控制。利用遗传算法对PID控制器的参数进行自适应整定,使直线电机在较短的时间内达到稳定值,并且调节过程中具有较小的超调量。采用频率法校正,将时域性能指标转化为频域特性参数,选用超前网络对系统进行校正。采用Simulink进行仿真,经过遗传算法调整后PID控制器与传统的方法提高了系统的静态性能,而频率法校正后的控制系统在保证精度的前提下大幅提高了系统响应速度,达到系统的设计指标。     

基于混合的多目标遗传算法的多目标流水车间逆调度问题求解方法*

将逆优化理论与方法引入车间调度领域,探讨近年来车间调度领域出现的一种新方法“逆调度”。研究多目标流水车间逆调度问题,建立考虑调度效率和调度稳定性的数学模型,综合考虑了加工参数改变量、系统改变量以及完工时间和等目标。提出一种基于混合的多目标遗传算法(Hybrid multi-objective genetic algorithm, HMGA)的求解方法,将多种策略进行混合以提高算法性能,主要包括快速非支配排序遗传算法(Non-dominated sorting genetic algorithm II, NSGAII)中的快速非支配排序方法、两种多样性保持策略、混合的精英保留策略,以及改进的局部搜索策略等。通过实例测试与方差分析(Analysis of variance, ANOVA),验证了该算法的有效性。     

基于改进遗传算法的高压直流输电系统逆变器定电压自抗扰控制器的设计

换流站中整流器和逆变器具有良好的控制性能是HVDC系统安全稳定运行的保证.自抗扰控制器(ADRC)对系统时变和不确定性干扰具有良好适应能力,但参数不易整定.本文将一种综合考虑控制器动态性能和被控对象输入受限的改进遗传算法应用到ADRC的参数整定中.将其应用到直流输电系统的逆变器控制器的设计中,仿真结果表明所设计的逆变器定电压自抗扰控制器具有良好的控制性能,对系统的外扰和模型参数的摄动具有良好的适应性.     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

考虑进油孔有限长滑动轴承油膜力的近似解析解

针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。     

Fifth International Summer School on Screw-Theory Based Methods in Robotics

正3-11 September,2014University of Bologna,Bologna,Italy www.summerscrews.org summerscrews2014.ing.unibo.it SUMMER 20SCREWS 14In 2014,our screw-theory school comes to the world's oldest university.In early September,Summer Screws'14 will gather six experts in the application of screw theory in robotics and up to 40 participants at the University of Bologna,Bologna,Italy.The school will teach attendees how to apply existing methods and empower them to develop new ones in their own research.The basic theoretical notions will be introduced in a rigorous manner,emphasizing examples,applications,and exercises.Scholarships are available.     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

INDUSTRIAL ENGINEERING AND VISUALISATION-A PRODUCT DEVELOPMENT PERSPECTIVE

Taking the actual project of teaching and researching process for example, the relationship between the industrial engineering and product development is discussed. And use the novel visualization technology to support the industrial engineering and product development. How to use the new computer modeling and simulating technologies to support the product development and industrial engineering, is introduced especially. The support includes both domestic products and industrial systems. The visualization and computer technologies take a very important role in some system or multi-direction modeling, those technologies mentioned above can help the industrial engineers study the effect of design on the whole life circle, including the producing steps. So the engineers can avoid making the wrong decision which may cause bad effects on the whole industrial engineering.     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...