純旋轉自由度之運動模擬系統之最佳化設計與控制

Abstract

本論文之研究目的在於運用一個純旋轉自由度之運動平台，對於運動模擬系統提出一個最佳化的設計與控制；對於X系列之運動控制平台結合最佳工作空間以及機械效益的設計之可行性，作深入性的探討與分析。此研究對於低成本之運動控制系統有其重要性。而最佳化目標函數之設計方法亦將呈現。本文所提出之方法結合了某些主要的課題如：工作空間的大小、工作空間的對稱性、以及驅動系統的輸出功率要求等。再者藉由採取一全域最佳化之程序-基因演算法，以及運用「逆向/正向」運動學所推導之成效指標所決定的展開角，可改善運動平台之靜態與動態的成效。此外，藉由一以即時最佳化演算法推導之運動線索控制策略，運用在前述之運動模擬系統-純旋轉自由度平台-可呈現翻滾、俯仰、偏轉、正衝以及側衝等五個自由度之動作。而權函數在每一個取樣時間皆可適應性地自我調整以獲得最佳歐拉角之解析解。此運動線索控制策略因其不需要遞迴地搜尋最佳解故能呈現出極佳的效率。實驗結果呈現其對於五自由度之運動模擬之正確性及有效性。此運動策略配合軟硬體的實現已應用在X2/X360之運動模擬系統上。

This dissertation presents an optimal method for designing and controlling a novel motion simulator system with only rotational degrees of freedom (DOF). The feasibility of adopting the design of X-series motion platforms to combine optimal workspace and mechanical advantage, which is considered important for low-cost simulators, is investigated. A design method to optimize an objective function is also presented. The proposed method consolidates some major issues associated with workspace volume, workspace symmetry, and actuator power requirements. Performance indices obtained from inverse/forward kinematics are adopted within a global optimization procedure, a genetic algorithm (GA), to determine the designed spread-angle that improves static and dynamic performance. Furthermore, an optimal motion-cueing strategy is applied to the designed simulator system with three rotational DOF to perform the roll, pitch, yaw, surge, and sway motions via an online optimization algorithm. Weighting functions are adaptively tuned in each step, and the optimal Euler angles are obtained analytically. This motion-cueing algorithm is efficient as it requires no recursive search on the optimal solution. Experimental results demonstrating the validity of the five DOF motion simulation are presented. The proposed algorithm is applied to X2/X360 motion simulators with software and hardware realization.