離散物件模擬系統之研究

A Versatile Discrete Object Simulation System

楊承道(Cheng-Tao Yang)

指導教授 ： 謝尚賢

國立臺灣大學/工學院/土木工程學研究所/博士(2004年)

https://doi.org/10.6342/NTU.2004.02168

摘要

本研究主要的目的，是要開發一個可以混合處理多種離散物件間的力學交互作用和多種形狀的離散物件模型的模擬系統原型。為了能夠完成這個目標，我們完成了四項主要的工作: (1)利用物件導向的設計模式(Design Partten) 開發出一個具高度彈性的離散物件模擬系統的軟體架構 VEDO。這個軟體架構可以同時處理多種相異的離散物件的數值模型以及離散物件間的交互作用，而且其在設計上更保留彈性，使得新的幾何形狀與求解演算法，可以很容易與既有的系統整合在一起。 (2)利用XML 相關技術開發出一套離散物件模擬標示語言。這套標示語言可以用來描述離散物件模擬問題，所包含的數值模型與記錄模擬結果，有利於研究者保存與分享資訊與加快相關應用程式的開發。(3) 討論與開發一些基礎的離散物件幾何模型及相關的演算法。這些基礎的幾何模型包含球、圓柱、薄板與多面體。另外也討論如何產生起始狀態與提昇演算效率的策略。 (4) 實作出一個離散物件模擬系統原型名為Knight&Anne，並利用多個應用範例來驗證這個原型系統之設計與實作的正確性與展示其軟體架構的彈性。

關鍵字

標示語言 ； 系統設計 ； 離散元素 ； 離散物件模擬 ； 物件導向 ； 設計模式

並列摘要

This study aims to prototype a versatile discrete object simulation system, which is one that can simultaneously handle discrete objects of various shapes with various interaction mechanisms. To achieve this, four major tasks have been done: (1) An Object-Oriented framework, named VEDO, for versatile discrete objects simulation using design patterns has been developed. VEDO is capable of handling simultaneously numerous mathematical models for representing discrete objects and solution algorithms for representing interactions among discrete objects. It also has great flexibility in facilitating additions of new discrete object shapes and solution algorithms for discrete object interactions. (2) An XML-based markup language, named dosXML, for describing, recording, sharing, and exchanging the numerical model and simulation data of discrete object simulation problems has be proposed. It can facilitate the development of discrete object simulation packages. (3) Numerical geometric models and correspnonding algorithms for several basic shapes of discrete objects are also presented. These basic shapes of discrete objects include sphere, cylinder, plate, and polyhedron. Simulation strategies for initial modeling and reduction of CPU time and memory usage are also discussed. (4) A prototype simulation system, named Knight&Anne, has been implemented to verify and illustrate the versatileness and flexibility of the design proposed in this study using several application examples.

並列關鍵字

System Design, Object-Oriented ； Design Patterns ； XML-based Markup Language ； Discrete Element Method ； Discrete Object Simulation

參考文獻

Liu YS (2002) Parametric Study of Discrete Element Method in Self-Compacting Concrete, Master Thesis, Department of Civil Engineering, National Taiwan University, Taiwan, ROC (in Chinese)

Baraff D (1991) Coping with Friction for Non-penetrating Rigid Body Simulation, Computer Graphics, SIGGRAPH91, Las Vegas, July 1991, 25(4):31-40

Baraff D (1994) Fast Contact Force Computation for Nonpenetrating Rigid Bodies, Computer Graphics Proceedings, Annual Conference Series, SIGGRAPH94, Orlando, July 24-29, 1994

Bernhard P, Algis D (2002) Numerical Simulation of the Motion of Granular Material Using Object-Oriented Techniques, Computer Methods in Applied Mechanics and Engineering. 191:1983-2007

Blilie C (2002) Patterns in Scientific Software: An Introduction, Computing in Science & Engineering, 4(3):48-53