PID控制器在带材跑偏控制系统中的应用研究

在分析带材跑偏控制系统的电液位移伺服系统控制原理的基础上,建立了系统的数学模型.对基于MATLAB环境的PID控制器的设计步骤作了详细介绍,提出了其设计思路和需要注意的问题,并通过仿真对加入PID控制器后的系统性能进行了分析验证,结果表明其能够达到预期的设计要求.     

500 KN恒力压力机电液伺服控制系统设计

恒力压力机是具有试验机性能的生产设备,其传动全部采用液压传动,双泵液压源,大泵实现快速,小泵慢速.利用伺服比例阀实现了慢速调节中加栽力、位移或其速率的恒定.控制系统以小型PLC和触摸屏为控制核心,自编的PID程序充分发挥了伺服比例阀和PLC性能,控制系统达到了设计要求.     

PLC及伺服技术在齿轮专用铣床改造中的应用

介绍一种普通铣床改造成齿轮加工专用铣床的方法,其控制系统主要包括小型可编程逻辑控制器和伺服驱动器.改造后的铣床不仅加工精度有了保证,而且大大降低了操作工的劳动强度,提高了生产效率.     

货车转向架综合检测台控制系统软件设计

针对由可编程序控制器、伺服驱动器、伺服电机、传感器等硬件组成的货车转向架综合检测台控制系统,介绍了控制系统软件功能设计,重点论述核心、关键的控制功能的设计与编程实现.该检测台已正式投入使用,系统运行安全、可靠.     

基于模糊控制的液压伺服控制系统研究

针对非线性的液压伺服控制系统,设计了一种常规PID控制器和一种模糊PID控制器,并分析了它们的优点和缺点。通过MATLAB仿真表明,该模糊控制器既具有常规PID控制器高精度的优点,又具有模糊控制器快速、适应性强、可靠性高的特点,为液压系统控制提供了可行的方案。     

五轴数控异形植毛机的控制软件设计

自主开发了五轴数控异形植毛机控制系统及软件,可对板刷进行五坐标联动快速定位,植毛速度可调整,适合不规则、非单一几何形状的异形毛刷及大型工业用刷。系统采用基于PCI总线的高性能运动控制卡,通过控制五个步进电机（或伺服电机）,实现工作台的精确定位。介绍了系统软件的模块化设计思想,给出了软件流程图,并提供了关键部分的控制代码。该设备克服了目前多坐标联动数控系统成本过高、编程麻烦的缺点,能够使工件做五坐标联动快速定位,植毛速度可达2～6孔/秒。     

基于CANopen总线的整经机控制系统

介绍了基于CANopen总线的整经机控制系统,以PLC为主控单元,以变频器控制经轴线速度恒定,利用伺服控制器的电子齿轮功能功能,实现牵引与卷绕线速度同步,另外使用了触摸屏来设定和监控工艺参数.     

绞车电液伺服速度控制系统的研究

以液压绞车为例,介绍了电液伺服速度控制系统的组成。通过建立控制系统的数学模型,分析了电液伺服速度控制系统各部件结构参数对动态特性的影响,提出了改善电液伺服速度控制系统动态品质办法,通过在Matlabsimulink模型中加入PI控制器对系统进行仿真,获得了控制系统的稳定性和动态特性。     

以WINCE为平台的排爆机器人控制系统设计

针对五自由度排爆机器人运动关节的高精度控制要求,提出基于嵌入式操作系统WINCE的机器人伺服控制方法.该控制系统控制器采用先进的PID控制方法,嵌入式计算机装载WINCE操作系统,并利用EVC工具编写相对应的应用程序控制软件.最终把编写的应用程序下载到机器人本体上的嵌入式PCI04计算机,运行结果表明,该方案取得了良好的效果,机器人关节运动平稳且无静态误差,系统具有很好的鲁棒性和实时性.     

西门子SIMOTION控制器在铆接设备中的应用

以西门子SIMOTION运行控制器为基础,通过实验铆接机对自动钻铆过程中的位置精度、压铆力控制等性能指标进行检测实验,实现SIMOTION控制器在铆接机中的应用设计。铆接控制系统包括SIMOTION运动控制系统、ADI4模数转换器、安川伺服驱动器、欧瑞变频驱动器、科尔摩根以及TOX伺服运行程序块。     

动力陀螺调谐仪力矩器定圈组件正交性误差检测装置的研制

力矩器定圈组件正交性误差检测装置是一台基于单片机控制的智能仪器，该机采用同步测量原理及数字滤波技术，实现各相误差的检测。重点介绍测量传感器的设计思想，信号检出变换原理及同步测控实现方案，并对软件设计进行介绍。该机体积小，操作简便，可供生产线上的半成品定圈组件和加工好的成品组件进行定性、定量的检测与筛选，适用于不同规格定圈组件的测试。     

彩管搬运机器人工作站

大型彩色显象管体积笨、重量大 ,搬运困难。本文结合已经在彩管生产线上投入使用的 7个机器人搬运工作站 ,综合介绍机器人搬运工作站的总体设计思想、末端执行器和同步跟踪装置等技术要点。这种技术同样适用于其它类似的搬运作业。     

Hydrodynamic Effects on the Boiling Interface in a Misaligned,Two-Phase,Mechanical Seal—A Qualitative Study

A qualitative study of the hydrodynamic effect on the radius at which boiling occurs in two-phase, misaligned, mechanical seals with coning is presented. The more important parameters affecting the problem are identified and analyzed. It is found that hydrodynamic effects depend mainly on a modified Sommerfeld number. It is shown that in most practical cases the hydrodynamic effects can be neglected men at large face misalignment. It is further shown that the boiling interface in many cases is practically axisymmetric and at almost the same radius as for perfectly aligned faces. A factor that reduces the tendency to cavitate in misaligned, two-phase seals is also pointed out.     

Surface coatings materials conservation and optimum tribological performance

Surface coating technology has received considerable attention in recent years. It improves corrosion, friction, wear and fatigue resistance of components with a minimum demand on scarce raw materials. It is shown that the behaviour of surface films depends on material properties, surface finish and film thickness and that friction may vary through two orders of magnitude due to such effects; the friction of soft metal films being low and that of hard films being high. Such effects are enhanced for very smooth surfaces and very thin films. It is also shown that the wear resistance is greater for thin soft metal films and less for thin hard metal films. Some experimental evidence is available to justify the theoretical proposition but much further work is required and the paper identifies the gaps in knowledge     

On the unique solvability of a direct dynamics problem for mechanisms with redundant constraints and Coulomb friction in joints

The uniqueness of simulated motion of an overconstrained rigid body mechanism with joint friction is studied. The investigated issue originates in the problem of joint reactions solvability. It is known that in case of redundant constraints existence the constraint reaction forces cannot be — in general — uniquely determined. It can be proved, however, that — under certain conditions — selected reactions can be specified uniquely. Analytical and numerical methods for reactions solvability analysis are available. It is shown in this paper that indeterminacy of normal reactions results in indeterminacy of friction forces, and moreover, non-uniqueness of friction forces results in non-uniqueness of simulated motion. A method of finding these joints, for which friction forces are unique, is presented. It is also proved that if only uniquely solvable friction effects are introduced, then simulated motion of the mechanism is unique, otherwise it is not. Finally, examples of dynamic analysis of overconstrained mechanisms with joint friction are presented; unique and non-unique results are obtained.     

A study of the lubricating effectiveness of micropolar fluids in a dynamically loaded journal bearing (T1516)

The lubricating effectiveness of micropolar fluids in a dynamically loaded journal bearing is studied. On the basis of the theory of micropolar fluids, the modified Reynolds equation for dynamic loads is derived. Results from the numerical analysis indicated that the effects of micropolar fluids on the performance of a dynamically loaded journal bearing depend on the size of material characteristic length and the coupling number. It is shown, compared with Newtonian lubricants, that under a dynamic loading the micropolar lubricants produce an obvious increase in the oil film pressure and oil film thickness, but a decrease in the side leakage flow. It is also shown that the friction coefficient for a dynamically loaded journal bearing with micropolar fluids is in general higher than that of Newtonian fluids, which is not the same as the results for a steadily loaded journal bearing. Furthermore, a parametric study of flow and friction for different mass parameters keeping micropolar parameters fixed is undertaken. It is indicated that, with the increase of the mass parameters, the crank angles corresponding to the maximum flow are changed and the maximum friction coefficients are obviously decreased either for the Newtonian fluids or for the micropolar fluids.     

铸造大学之魂

“铸造大学之魂”是一个重大的哲学命题。“文化是大学之魂”深深地蕴涵在“育人是大学之本”和“科学是大学之根”之中,其核心是大学应当坚守的文化品位和崇高理想。主要凝聚在深厚的文化底蕴之中的大学文化是一种独特的社会文化形态,是大学赖以坚守文化品位和崇高理想、承担起历史赋予的重大使命的根本。铸造大学之魂,对于大学办学来说,是一项非常有意义的基础性、全局性和战略性的工作,应当与时俱进,持之以恒。     

FDM analysis for MHD flow of a non-Newtonian fluid for blood flow in stenosed arteries

A computational model is developed to analyze the effects of magnetic field in a pulsatile flow of blood through narrow arteries with mild stenosis, treating blood as Casson fluid model. Finite difference method is employed to solve the simplified nonlinear partial differential equation and an explicit finite difference scheme is obtained for velocity and subsequently the finite difference formula for the flow rate, skin friction and longitudinal impedance are also derived. The effects of various parameters associated with this flow problem such as stenosis height, yield stress, magnetic field and amplitude of the pressure gradient on the physiologically important flow quantities namely velocity distribution, flow rate, skin friction and longitudinal impedance to flow are analyzed by plotting the graphs for the variation of these flow quantities for different values of the aforesaid parameters. It is found that the velocity and flow rate decrease with the increase of the Hartmann number and the reverse behavior is noticed for the wall shear stress and longitudinal impedance of the flow. It is noted that flow rate increases and skin friction decreases with the increase of the pressure gradient. It is also observed that the skin friction and longitudinal impedance increase with the increase of the amplitude parameter of the artery radius. It is also found that the skin friction and longitudinal impedance increases with the increase of the stenosis depth. It is recorded that the estimates of the increase in the skin friction and longitudinal impedance to flow increase considerably with the increase of the Hartmann number.     

圆弧轨迹调节装置的研究与应用

结合FWX20型封头冷旋压机的研制，介绍一种与该机匹配使用的新式圆弧轨迹调节装置。它具有设计结构新颖、简单及合理等特点。实践证明，该装置使用性能可靠，操作方便，并且提高了旋压机的加工性能和工作效率。     

产品与过程集成——先进制造模式的共性特征

阐述了产品技术,过程技术及其集成的概念以及产品与过程集成已经成为先进制造模式的共性特征,同时介绍了美国在产品与过程集成方面所作的努力及取得的成就。