PC Cluster-based CAVE
(Click to download Demo Video)
In order to create a large-scaled display
of the interactive virtual environment, surround-screen
projection-based VR systems or multi-projector rendering
systems were developed and have become popular research
topics in the recent years. CAVE is the pioneer of such VR
systems. The legacy CAVE system was built with four SGI
high-end workstations to create a four-sided surrounded
image with one workstation for each display wall, and a
fifth computer for the user’s input. In addition, they use the fiber
optic reflective memory, which is a cache shared device,
to synchronize the screen update on all four display
hosts. Hence, it is obvious that the main shortcoming of
CAVE is that it is too expensive and restricted by the
available hardware and software.
To cost down the CAVE system, we designed a hardware synchronization box (illustrated below) for PC-cluster environment. The core of the synchronization box is a hardwired synchronization protocol to trigger and transmit synchronization signal among cluster of PCs. With this box and the distributive graphical technique, we can easily construct a PC-CAVE system.
This technique had already successfully applied to several applications. For example, the cabin on the motion platform of the mobile crane simulator is equipped with three displays to provide the left, front, and right out-of-widow view for the player.
Our lab also setup such a PC-CAVE environment, as depicted below, for further researches.
We also helped MND, Taiwan, construct a proto-federation of a helicopter simulator. Different from the setup of mobile crane, a back projection technique was adopted to provide wider visual effect.
[Related Publication]
● J.Y. Huang, Kuei Min Wang, and Kuan-Wen Hsu, “The Frame Synchronization Mechanism for the Multi-Rendering Surrounding Display Environment”, Displays, Elsevier Science, Vol. 25, Issue 2, August 2004, pp.89-98. (EI, SCI) (pdf)
● J. Y. Huang and C.Y Kuo, “Modeling and Designing A Low-Cost High Fidelity Mobile Crane Simulator”, International Journal of Human-Computer Studies(Elsevier Science), Vol. 58, Issue. 2, February 2003, pp. 151-176. (EI, SCI) (pdf)
[Patent]
● J. Y. Huang and H.S. Bai, “The multi-display synchronization technique for the virtual environment”, new invention patent, Taiwan, patent no. 556088.
● J. Y. Huang, “The mechanism of data synchronization among multiple computers through their parallel ports”, , new invention patent, Taiwan, patent no. 153129.
叢集式平台上之環場視效
在製作行政院勞委會勞工安全衛生研究所之起重機模擬系統過程，黃俊堯老師進一步帶領研究生研發出環場視效的多台電腦螢幕同步技術，藉由此同步技術我們可以 輕易地在個人電腦群組環境建構一個環場視效空間。
傳統的環場視效空間是靠高等級的多處理器工作站級伺服器系統來達到顯示畫面同步計算與視效同步的功能，例如，芝加哥的伊利諾州立大學EVL實驗室(Electronic Visualization Laboratory)所設計的環場視效空間(CAVE)是採用採用了四台Silicon Graphics Inc公司的工作站級電腦來作為顯示處理，在電腦之間則採用Systran公司的fiberoptic reflective memory來達到資料傳遞及畫面同步更新的工作。但是隨著電腦科技的進步，今日 的個人電腦所擁有的計算速度已超過昔日工作站等級的電腦，而分散式計算是今日電腦技術研發趨勢，因此，黃俊堯老師藉由分散平 行運算技術及環場螢幕同步技術在多台個人電腦所構成的電腦群組環境建構一個高解析度低成本的視效空間。在視效同步機制上，黃 俊堯老師設計了如下圖的同步盒(Synchronization Box)作 為多台電腦之間畫面同步訊號的控制機制，藉由此同步控制盒及分散式圖學計算技巧，我們可以輕易的以個人電腦群組來建構一套環 場視效系統(CAVE)。
而此環場視效系統已應用於行政院勞委會勞工安全衛生研究所之起重機模擬系統，如下圖所示之起重機模擬器駕駛艙。
也可在實驗室架設如下圖的環場視效系統來進一步研究立體顯像技術以及其它可能的應用研究。(展示影片)
此外，此技術以曾替軍方設計戰搜直昇機的模擬駕艙雛型系統，如下圖所示。此套模擬系統與行政院勞委會勞工安全衛生研究所之起重機模擬系統的最大不同點是， 本次所設計的環場視效系統是採用背投影式玻璃的呈像技術，呈現更寬廣的視覺效果與更真實的模擬效果。
[相關論文]
● J.Y. Huang, Kuei Min Wang, and Kuan-Wen Hsu, “The Frame Synchronization Mechanism for the Multi-Rendering Surrounding Display Environment”, Displays, Elsevier Science, Vol. 25, Issue 2, August 2004, pp.89-98.(行 政院國科會NSC90-2213-E-032-015) (EI, SCI) (pdf)
● J. Y. Huang and C.Y Kuo, “Modeling and Designing A Low-Cost High Fidelity Mobile Crane Simulator”, International Journal of Human-Computer Studies(Elsevier Science), Vol. 58, Issue. 2, February 2003, pp. 151-176. (行 政院勞委會補助計畫IOSH89-S131) (EI, SCI) (pdf)
[專利]
● 黃俊堯，白華勝，“虛擬實境之多螢幕同步顯像系統及其方 法”，中華民國發明專利案，2003年10月1日公 告，專利公報公告編號第556088號。(國科會補助計畫90-2213-E-032-015)
● 黃俊堯，“並列埠之多台電腦資料同步控制裝置及 方法”，中華民國第153129號 發明專利案。專利期間為中華民國91年3月至中華民國109年10月。(行政 院勞委會補助計畫IOSH89-S131)