一种研究空间机构震动力完全平衡的方法及其应用

本文提出了一种研究空间机构震动力完全平衡的新思路,并由此导出两种空间机构(空间RSS'R(Ⅱ),RRRSR)震动力完全平衡的条件。这些条件比用其它方法导得的条件更为宽松和简单。     

PRODUCT MODELLING TO SUPPORT PRODUCT DEVELOPMENT IN A VIRTUAL ENTERPRISE

The concept of Virtual Enterprise (VE) is closely related to the Global Manufacturing (GM) paradigm. How to develop a computer system which supports the product development in VE is an issue to be discussed in this paper. The emphasis is placed on the product modelling in the VE context. In the paper, a new concept of information modelling called 'heterogeneous data' situation is clarified, which is further related to the 'Instance As Type' (TAT) phenomenon. Modelling for IAT is discussed. Modelling for the partner company behaviour is presented as well.     

基于冗余伺服电机的平面四连杆机构震动平衡

为了更好地解决平面连杆机构震动平衡问题,提出一种新的平衡概念——冗余伺服电机法.详细介绍了冗余伺服电机法的概念及其平衡平面连杆机构动力学参数的工作原理,并给出实例以介绍该方法的设计过程和验证其对平面连杆机构震动力矩和输入转矩平衡的有效性.     

THE EXTENDING OF JOUKOWSKY''''S LEVER METHOD AND ITS APPLICATIONS IN LINKAGE PROBLEMS

Joukowsky's Lever Method is the method used to find out the equilibrant and balancingmoment of various mechanisms.The advantage of this method is to save the complicated processof finding out the reactional forces in kinematic pairs.But,the method is only limited to thosemechanisms composed of rigid bar linkages and with negligible friction.In practical cases,hydropneumatic elements and spring constraints may be included in the mechanism;and alsowith the development of high load,high speed and high accuracy of mechanism,the friction maynot be neglected.So,the authors have tried to develop the Generalized Joukowsky's LeverMethod,which can be used to find out the equilibrant and balancing moment of the mechanismwhen the hydropneumatic elements and spring constraints are included and the friction inkinematic pairs has to be considered.Three examples are here analyzed to show the applicationsof this method.     

工业缝纫机上下差动送料系统的分析研究

具有上下差动送料功能的工业平缝机国内至今还未试制成功。本文对其中具有代表性的日本DLU-490型机进行了分析与研究。该送料系统是由含多个复杂高级平面机构组成,在输入运动的一个周期中,送料系统中的机构形态发生变形。本文主要揭示该送料系统的动作机理、建立了送料牙运动轨迹方程,并用计算机模拟合理的送料动作,从而得出系统中各机构之间的相位角。为设计安装调试提供了依据。而且也适用于其它种类的具有上下差动送料功能的工业平缝机。     

齿轮传动系统非白噪声随机误差激振的建模

发展了考虑速度影响的时变非白噪声齿轮随机误差的模型 .方法是首先将齿轮传动误差分解为周期性和随机性两部分 ,然后采用时变二阶马尔克夫过程模拟齿轮非白噪声随机性误差 .二阶马尔克夫过程用作成型滤波器 .成型滤波器的输入为白噪声 ,输出即为齿轮非白噪声随机误差 .利用该随机误差模型 ,发展了新的齿轮回转方向随机振动动态模型 .进而讨论了齿轮随机误差对齿轮回转振动的影响 .     

一类空间 4R-C 过约束条件的探讨及其在纺织机械中的应用

本文应用封闭环矩阵形式方程论证了一类空间4R-C 五杆过约束机构。进一步研究表明:在这类过约束机构中,当两组平行轴相互垂直交叉时得到下列新结论:1.对由 R、C 组成的这类机构,C 副安置在哪一个轴上,应满足一定的限制条件,否则就不能实现主、从动轴间的相对空间运动。2.对由 H、C 组成的这类机构,在特定的螺矩关系下,C 副的任意安置仍有可能;即对 H 副成立的结论不能无条件地推广到 R 副上。应用上述结论,作者设计了空间 RRCRR 机构(这类过约束机构的一种),应用于织机多臂提综装置,经试验运转效果良好。     

ANINVESTIGATION ON THE REPLACEMENT OF SPHERICAL PAIR BY CROSS-HEAD PAIR IN SPATIAL MECHANISMS

The spatial RSSR crank rocker mechanism is widely used in industry, but, the manufac-turing, mounting and lubrication of S pair are more complicate than R or C pair. This paperdeals with the replacement of S pair by cress-head pair and investigates the equivalence of thetwo mechanisms with output angular displacement and oscillating angle ψ, as the object func-tion. The synthesis in terms of velocity ratio K and ψ and the influence of the cross-headstructure on the replacement have also been discussed.     

工缝机的差动送料机构与缝纫性能

在“工缝机上下差动送料系统的分析研究”一文中,我们建立了上下送料牙运动轨迹方程,并用计算机进行模拟计算,确定出各机构之间的相位角以及某些可调参数值。本文在此基础上探讨了各机构之间的相位角对缝纫送料性能的影响,得出相位角的最佳值及允许变动的范围。这对机器的设计和安装有重要意义。     

基于小波神经网络的船舶运动预报

利用残值学习算法进行小波节点的选择,利用Akaike 准则确定预测模型的结构,采用误差反传方法在线调整网络连接参数.通过建立的自适应神经网络模型有效辨识船舶操纵运动动态.船舶航向预报仿真结果显示,基于小波神经网络的船舶航向预测器可以较高精度预报船舶操纵运动过程中船舶航向的变化.