Abstract : in this paper , the kinematically admissible velocity fields are established by using the metal flow patterns based on the experiments , and the configuration dimensions of billet and the curves of load - stroke in precision forging process for spur gear from solid billet are simulated on computer by upper bound method . the results acquired in the simulation are in good agreement with those obtained in the experiments 文摘:本文利用有实验根据的变形流动模式建立动可容速度场，利用上限法模拟用实心坯料精锻直齿圆柱齿轮时坯料的外形尺寸变化和力?行程曲线，所得结果与实验测定值很一致，可供冲挤精锻工艺设计参考。
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Because the kinematically - admissble cyclic strain rate field required in kninematical - type theorem of shakedown analysis is rather difficult to be constructed , shakedown analysis based on kinematcal theorem cannot be directly applied . some conditions of kinematical - type shakedown theorem are released by ksnig and then the shakedown rules respectively for alternating plasticity and incremental collapse are obtained , for the numerical method based on the upper - bound theorem is formulated 两种方法的特点是：运用一种分级循环加载方式来寻找机动许可的塑性应变率场，利用这两种机动安定准则的特点来判断结构的安定性，从而得到机动安定性分析的安定载荷。
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Fifthly , by adopt new matrix coordinate system means , found a tricycle wmr ' s kinematic model , especially the investigation in the kinematically modeling of steered wheel and non - steered wheel . at the same time , the dynamic modeling of robot ' s playing football motion , consummate mobile robot ' s system . by the comparison with the two - wheeled differential drive structure on line or circular track ' s simulation experiment result , illustrate the tricycle wmr ' s superiority more and more 第五，采用新型的矩阵坐标系方法，建立了三轮式机器人的动力学模型，尤其是在导向轮和非导向轮的动力学建模方面进行了深入的研究；同时，对机器人踢足球的运动进行动态建模，进一步完善了移动机器人体系。
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The cable - strut tensile structures are the self - stress equilibrium systems composed by tensional cables and struts . in this paper , the basic concept of the structures was described . the analysis methods of the structural characteristics ( statically and kinematically determinate or indeterminate ) and the geometrical stability were presented . it is indicated that the cable - strut tensile structures are in stable equilibrium with first - order infinitesimal mechanisms . the ranks of equilibrium matrix were calculated by employing the singular value decomposition , and the independent modes of inextensional mechanisms and the states of self - stress were also obtained in the same way . this paper contains some typical examples which illustrate all of the main points of the work 索杆张力结构是指由张力索和压杆组成的、具有预应力自平衡的新颖结构体系.本文详细阐述这种结构的基本概念和结构特征，讨论结构静动定体系特性和几何稳定性判定分析方法，指出索杆张力结构应具有一阶无穷小机构的几何稳定体系.文中采用奇异值分解方法计算结构平衡矩阵的秩，并计算独立机构位移模态和自应力模态.最后，对几种典型的索杆张力结构进行了算例分析
