Modelling of Dynamic Behavior of Machine Assembly with certain Machining Accuracy for Assembled Parts

本研究的目的是建立一种机械产品的建模方法，用于分析加工形状误差对装配机械产品功能运动精度的影响。根据机床和加工方式的不同，对各种类型的加工误差进行了分类，提出了根据加工误差修正零件形状的建模方法。研究了一种模拟机械装配体在各种形状误差条件下的动态行为的方法。特别是一个有效的方法，刚体组装和复杂的方法，柔性和可变形的物体被认为是。对于刚体运动的情况下，有效的和计算鲁棒性的算法被开发用于检测对象之间的干扰，这是根本上重要的模拟任意运动下未知的形状变化。在刚性物体之间可以施加任何约束，以满足原始产品的功能机制。对于柔性体的分析，引入了通用有限元分析方法，以允许对机器功能有关键影响的各种类型的加工和劣化误差。为便于复杂产品的生成，定义了弹簧、橡胶衬套、滚子等柔性零件的模型。该方法已用于分析复印机的输纸和复印机构的行为。通过仿真分析，发现了一些由于组成部件的误差而导致的机器意外故障。进一步加强分析方法是必要的，以处理各种错误类型。

The aim of this research is to establish a modelling methodology of machine products for analyzing the effects of machining shape errors to the accuracy of functional kinematic motion of assembled machine products. Various types of machining errors are classified according to the difference of machine tools and machining modes, and the modelling methods have been developed for modifying parts shape according to the imposed machining errors. A method for simulating dynamic behavior of machine assembly under the various part shape error conditions has been investigated. Particularly an efficient method for rigid body assembly and a sophisticated method for flexible and deformable objects are considered. For the case of rigid body motion, efficient and computationally-robust algorithms are developed for detecting interferences among object, which is fundamentally important for simulating arbitrary motion under unknown shape variations. Any constraints can be imposed among rigid objects to satisfy functional mechanisms of the original products. For the analysis of flexible bodies, a general Finite Element Analysis method is introduced to allow various types of machining and deterioration errors which have critical influences on machine functionality. Models of flexible parts, such as springs, rubber bushes and rollers, are defined for easy generation of complicated products. The developed method has been applied for analyzing the behavior of paper feed and copying mechanism of a copying machine. Some of the unexpected malfunctions of the machine are detected due to the error of the composing parts by this simulation analysis. Further enhancement of the analysis method is necessary for dealing with wide variety of error types.