適應性沖淡濾波器演算法應用於動感駕駛模擬器之研究

A Study of Applying Adaptive Washout Filter Algorithm Motion Cue to a Driving Simulator

黃裕祺(Yui-Chi Hwang)

指導教授 ： 曾百由

國立臺北科技大學/機電學院/機電整合研究所/碩士(2011年)

摘要

史都華平台是最常見的動感模擬平台，但由於其機構限制了工作空間，無法直接產生駕駛載具時持續的真實動態，故一般多以沖淡濾波器演算法作為史都華平台模擬動感的方法。
本研究深入探討沖淡濾波器演算法作為動感法則的需求與表現，並提出創新的適應性沖淡濾波器演算法，期望利用此演算法搭配自製的數位平台控制器，使得史都華平台表現出的運動動態更符合人體感知。
由於傳統的沖淡濾波器是線性的，平台的運動量與命令幅度成正比，因此命令幅度越大時平台越容易達到臨界空間。本研究以傳統沖淡濾波器演算法為基礎，加入適應性調變機制，根據平台不同的位移量即時調變沖淡濾波器的轉折頻率，以便讓平台於工作空間及動態命令間取得平衡。
在實驗部分，本研究除了使用步階及掃頻訊號測試各種沖淡濾波器的表現外，並利用虛擬實境軟體Virtools內部的物理模型計算模擬汽車於市區行駛時的各種駕車動態，透過史都華平台搭配適應性沖淡濾波器呈現，以驗證本研究的可行性。

關鍵字

動感法則 ； 沖淡濾波器演算法 ； 史都華平台 ； 數位平台控制器

並列摘要

Stewart Platform is the most popular motion platform used to generate motion cue. However, the workspace prohibits it from producing continuous dynamic motion as those in the real world. In most circumstances, a Washout Filter Algorithm is applied as the motion cue to generate motion on the Stewart Platform.
This research investigates the demands and performance using Washout Filter Algorithm as motion cue. Because the Classical Washout Filter is linear, motions of the Stewart Platform vary proportionally to the commands, once the amplitude of command becomes larger, the platform will reach its workspace boundary. An innovative Adaptive Washout Filter Algorithm is also proposed and investigated to improve the performance. With the new adaptive method and in-house developed digital platform controller, the Stewart Platform is controlled to produce the motion closed to the simulated dynamics while satisfies the human perception.
The study started with the Classical Washout Filter and an adaptive variable method has been applied by adjusting the break frequency of Washout Filter in realtime according to the varying space available of the platform. By adopting the adaptive method, the performance between simulated dynamics and the physical workspace limitations of platform can be optimized.
To prove the feasibility of this research, step and sweep signals firstly are applied to examine the performance of all Washout Filters; secondly, a physical vehicle dynamic model in virtual reality is adopted to calculate and simulate the real-world motion dynamics and then the simulated motions have been reproduced by Stewart Platfrom and the develpoed Adaptive Washout Filter algorithm. The experiments have shown the advantages of the developed Adaptive Washout Filter algorithm which surpasses the Classical ones.

並列關鍵字

Motion Cue ； Washout Filter Algorithm ； Stewart Platform ； digital platform controller

參考文獻

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