Simulating Virtual Crowd by Motion Planning for Reshapable Object and Fuzzy Rules

群體運動在現今的電玩、動畫或電影中，有十分重要的應用；透過群體性的運動，可以表現出故事背景設定的張力。在群體運動的模擬中，除了個體本身的運動行為模擬外，重要的是如何呈現出群體運動的整體效果。過去文獻中多數的群體運動模擬系統，要能在群體運動中呈現出特定形狀的效果，多需花費大量的時間反覆調整個體的模擬結果；個體本身的運動行為模型，則多採用虛擬力場的方式，被動的影響個體的運動，較缺乏直觀設定行為模型的方式。本論文的目標是建立一套人群模擬系統，此系統包括兩個部份：第一個部份是使用者可根據個人偏好設定群體運動理想中的外觀形狀，使此系統在模擬前能根據所輸入的環境資訊，利用運動計畫的方式，自動產生形體形變的路徑，以做為維持群體外形的參考目標。第二部份則是改進人群模擬時個體與群體的行為模型。我們利用模糊數學的特性，來表示行為模型以語意表達時的不確定性，使個體的行為能表現出貼近使用者所需求的結果。我們提出了三種類型的模糊行為模型與對應的原生動作，用以表現個體與群體的運動行為。根據我們實做出來的系統及實驗顯示，透過這樣的系統，我們可以利用程序化的方式為電腦動畫師產生具有特定群體外觀的群體模擬，減少其在製作相關動畫所需要的時間與技術成本，同時也提供了直觀的方式建立人群的行為模型，增加行為的豐富性。The effects of crowd behavior are becoming indispensable in computer games and computer animation. In crowd simulation, beside the issue of simulating the motion for individual agents, the more important one is how to simulate a specific behavior of a crowd based on the motion of individuals. In order for a crowd to conform to a specific shape, most simulation systems reported in the literature require the users to spend a great amount of time in tuning the behavior parameters of each individual, governed by virtual forces computed according to inter-agent relations. In this thesis, we aim to build a system of crowd simulation consisting two parts: a path planner for a flexible shape and a motion controller with fuzzy logic. The path planner can search for a feasible path for a region of flexible shape allowing the user to set his preference on the shape of the crowd. The local motion controller for each agent is based on fuzzy logic rules that can be used to present the uncertainty of linguistic behavior models. We have proposed three types of fuzzy behavior models and their corresponding primitive actions. Our experiments show that, with this simulation system, we allow a computer animator to use an intuitive way to create specific appearance and richer