黃河下游交互式三維視景系統(tǒng)開發(fā)應用研究

1、黃河下游交互式三維視景系統(tǒng)開發(fā)應用研究王軍良 程 冀 王 彤 談 皓 何劉鵬 張繼勇 陳新燕 馬迎平黃河勘測規(guī)劃設計有限公司，河南鄭州，450003一、研究背景為了實現(xiàn)新時期的治黃目標，全面貫徹落實水利部新時期的治水思路，黃委提出建設“數(shù)字黃河”工程?！皵?shù)字黃河”就是把黃河裝進計算機，在計算機中建立原型黃河的虛擬對照體，從而可方便地模擬、分析、研究黃河的自然現(xiàn)象，探索其內(nèi)在規(guī)律，為黃河治理、開發(fā)和管理的各種方案決策提供技術支持?！包S河下游交互式三維視景系統(tǒng)”是“數(shù)字黃河”工程建設的一個基礎設施，系統(tǒng)研究如何把黃河下游直觀、形象、系統(tǒng)地裝進計算機，在計算機中建立現(xiàn)實黃河下游的虛擬對照體，為黃河下

2、游治理、開發(fā)、研究提供一個三維可視化決策分析平臺。 二、研究目標通過GIS、RS、三維建模、虛擬現(xiàn)實等先進的計算機技術，把黃河下游直觀、形象、系統(tǒng)地裝進計算機，在計算機中建立現(xiàn)實黃河下游的虛擬對照體“黃河下游交互式三維視景平臺”，在這個平臺上可以開發(fā)和掛接防洪、水調(diào)、工程建設與管理等多種應用系統(tǒng)，使之成為既能直觀系統(tǒng)地反映黃河下游防洪工程基本情況，又能為防洪工程規(guī)劃、建設管理、下游防汛、水量調(diào)度提供應用的一個綜合性的可視化服務平臺。從而為黃河下游的治理開發(fā)提供強大的三維可視化決策支持環(huán)境。三、研究內(nèi)容及成果“黃河下游交互式三維視景系統(tǒng)”表現(xiàn)范圍為黃河小浪底，到黃河入?？?00多公里的河道，系統(tǒng)

3、對黃河下游河道、小浪底水利樞紐、黃河下游臨黃大堤、險工、控導、防護壩、放淤固堤工程、各類涵閘，橋梁、河務局、防汛倉庫、村莊等數(shù)以萬計的工程地物及樹木、標注等數(shù)十萬計的非工程地物采用三維技術能進行逼真表現(xiàn)。在系統(tǒng)提供的三維虛擬環(huán)境下，既可以從宏觀角度全方位研究考察整個黃河下游工程的整體布局，直觀了解每處工程的作用及各個工程之間上下游左右岸之間的相互關系；也可以近距離對某處工程進行多角度、交互式地控制瀏覽察看，并能夠方便快捷地查詢工程的特征屬性信息，系統(tǒng)了解工程的建設運行情況。黃河下游交互式三維視景系統(tǒng)用戶界面如圖1所示。圖1 黃河下游交互式三維視景系統(tǒng)用戶界面整個系統(tǒng)由交互式三維視景平臺、虛擬三

4、維場景、系統(tǒng)數(shù)據(jù)庫三個主要部分組成，具有海量三維數(shù)據(jù)管理的有效性、數(shù)據(jù)更新的靈活性、海量三維場景交互控制瀏覽查詢的快捷性、屬性數(shù)據(jù)表現(xiàn)的多樣性、三維環(huán)境GIS分析以及和“數(shù)字黃河”其它應用系統(tǒng)可結合性等功能特點。系統(tǒng)首次實現(xiàn)了大尺度、高精度三維虛擬技術在水利界的應用，主要在以下幾方面有所創(chuàng)新：（1）首次采用地理信息系統(tǒng)、虛擬現(xiàn)實、三維建模、數(shù)據(jù)庫管理等技術把整個黃河下游裝進了計算機，在計算機中建立了整個黃河下游虛擬對照體黃河下游三維數(shù)字平臺。（2）實現(xiàn)了對海量數(shù)據(jù)的有效管理?！包S河下游交互式三維視景系統(tǒng)”管理和表現(xiàn)了黃河下游小浪底以下至黃河入?？?00多公里的河道場景，在場景中利用三維實體模型

5、對控導、險工、防護壩、涵閘、堤防等防洪工程，以及防汛機構、橋梁等地物進行了逼真表現(xiàn)。（3）系統(tǒng)首次實現(xiàn)了在海量三維環(huán)境下多分辨率、多精度衛(wèi)星影像及地形數(shù)據(jù)的嵌套功能。（4）系統(tǒng)首次開發(fā)了在三維環(huán)境下的交互控制、沿線飛行、工程定位、飛行定位等多種組合瀏覽查詢方式，可以靈活地對海量場景進行交互式控制瀏覽、查詢定位，使場景在瞬間精確定位到場景任一工程地物位置，方便快捷查詢工程地物屬性信息。（5）系統(tǒng)首次開發(fā)了河道斷面動態(tài)沖淤分析功能，通過這一功能可以動態(tài)繪制歷年河道斷面圖，動態(tài)顯示河道斷面的沖淤變化過程，分析研究河道沖淤變化規(guī)律。四、系統(tǒng)應用研究建成的黃河下游交互式三維視景系統(tǒng)是一個具有海量數(shù)據(jù)信息

6、、基于地理坐標控制、表現(xiàn)直觀、操作靈活方便、具有強大三維查詢分析功能、可進行二次開發(fā)的虛擬三維數(shù)字平臺系統(tǒng)?？蔀閺囊韵聨讉€方面為黃河下游治理開發(fā)提供支持：(1) 系統(tǒng)提供了一個認識黃河、了解黃河、研究黃河的平臺系統(tǒng)提供了與現(xiàn)實黃河下游相對應的三維景觀，工程地物與現(xiàn)實黃河下游一一對應，同時與工程屬性信息建立聯(lián)系，點擊可查詢工程地物詳細的屬性信息。靈活方便的交互控制瀏覽方式，突破現(xiàn)場查勘視覺限制的場景表現(xiàn)方式，可以從宏觀到微觀全面系統(tǒng)考察研究整個黃河下游，可提供比二維系統(tǒng)更為強大的信息支持。同時系統(tǒng)提供的河道斷面分析功能、基于三維場景的地形斷面繪制功能、面積量算功能、距離測量功能為認識研究黃河下游

7、提供了必要的技術手段。通過該平臺可以快速認識、了解、研究整個黃河下游，為黃河下游的治理開發(fā)提供一個全面、系統(tǒng)、可視化的研究分析平臺。(2) 為黃河下游防汛提供一個可視化的決策支持平臺在系統(tǒng)平臺上可以開發(fā)掛接工情險情會商系統(tǒng)，建立三維可視化工情險情會商系統(tǒng)。在系統(tǒng)建立的“數(shù)字虛擬”平臺上開發(fā)掛接基于GIS的二維洪水演進模型，可以為黃河下游防汛提供可視化的決策支持。每年汛前利用先進的測量技術，對黃河下游河道進行測量，根據(jù)測量結果修正“數(shù)字虛擬”平臺的數(shù)字高程模型，然后在該虛擬平臺上進行洪水調(diào)度預案的生成與模擬。我們可以把不同級別、不同成因、不同工程條件下的洪水過程在該平臺上進行模擬演進，在數(shù)字虛擬

8、平臺上直觀的看到不同級別洪水在河道的演進過程。根據(jù)洪水演進結果，可以制訂不同級別洪水條件下下游灘區(qū)人員撤退方案或其它有效的避險措施；對可能出現(xiàn)險情的工程，確定需要在多長時間內(nèi)做好料物、人員、機械設備等搶險準備工作。當某一級別洪水發(fā)生時，就啟動某個洪水調(diào)度預案，在虛擬平臺上進行實時洪水演進，直觀顯示洪水演進過程，通過虛擬平臺進行可視化的搶險調(diào)度指揮，當某處工程出現(xiàn)險情時，可以在三維平臺上點擊該處工程，調(diào)出該處工程的搶險預案，進行可視化的搶險調(diào)度指揮，做到有的放矢，變被動防洪為主動防洪，最大限度降低黃河下游洪水災害損失。(3) 為水量調(diào)度管理提供一個可視化應用服務平臺在系統(tǒng)提供的三維虛擬平臺上可以

9、直觀查看每個引黃涵閘的詳細屬性信息，了解每處工程的運行情況。與涵閘遠程監(jiān)控系統(tǒng)掛接，在虛擬三維環(huán)境下可視化控制不同閘門引水過程，提高水量調(diào)度管理水平。(4) 為黃河下游防洪工程規(guī)劃、建設、管理提供了一個工作平臺在系統(tǒng)提供的三維虛擬平臺上可以直觀系統(tǒng)地察看黃河下游工程的總體布局，可以看到哪些河段工程布點不足，或是已建工程不夠完善。通過衛(wèi)星影像的動態(tài)更新可以掌握河勢的演變規(guī)律，發(fā)現(xiàn)河勢頻繁上提下挫不能得到很好控制時，通過本系統(tǒng)可直接對工程的節(jié)點布置、工程上延下續(xù)進行規(guī)劃。為黃河下游防洪工程建設提供決策支持。(5) 和數(shù)學模型結合，可以成為模擬研究黃河下游河道規(guī)律的虛擬試驗平臺。黃河下游交互式三維視

10、景平臺是整個黃河下游的虛擬對照體，地形要素與現(xiàn)實黃河下游地形保持一致，工程、地物與現(xiàn)實黃河下游一一對應，基于地理坐標控制的三維場景可以方便的與基于GIS的數(shù)學模型相結合，從而形成一個模擬研究黃河下游河道規(guī)律的模擬試驗平臺。五、結語黃河下游交互式三維視景系統(tǒng)是黃河流域交互式三維視景系統(tǒng)的一期工程，本階段主要研究如何把黃河下游裝進計算機，建立整個黃河下游虛擬三維數(shù)字平臺，實現(xiàn)三維場景的交互瀏覽及信息的查詢、顯示分析功能。下階段將重點研究系統(tǒng)與“數(shù)字黃河”其它應用系統(tǒng)結合問題，同時把系統(tǒng)擴展到整個黃河流域，建立整個黃河流域交互式三維視景平臺，為流域治理開發(fā)提供三維可視化的決策支持。Developme

11、nt and Application Research of the Interactive ThreeDimensional (3D) Visual System of the Lower Yellow RiverWang JunLiang, Cheng Ji, Wang Tong, Tan Hao, He LiuPeng, Zhang JiYong, Chen XinYan, Ma YingPing I Research BackgroundIn order to realize tasks of the Yellow River control in the new period and

12、 overall carry out the thought for water control of the Ministry of Water Resources in the new period, the Yellow River Conservancy Commission proposes to establish the “Digital Yellow River” project which makes all the data relevant to the lower reach of Yellow River input into the computer and est

13、ablish the virtual comparison body of the prototype Yellow River so as to conveniently simulate, analyze and research the natural phenomenon of the Yellow River, and probe its internal laws to provide technical support for the various projects and policies of control, development and management of t

14、he Yellow River. The “Interactive ThreeDimensional Visual System of the Lower Yellow River” is one basic facility for building the “Digital Yellow River” project, and systematically study how to make all the data relevant to the lower reach of Yellow River input into computer in a visual and systema

15、tical way and establish the virtual comparison body of actual lower Yellow River in the computer so as to provide a 3D visual decision-making analysis platform for control, development and study of the Lower Yellow River. II Research ObjectThe research object is to make all the data relevant to the

16、lower reach of Yellow River input into the computer in a visual and systematical way by advanced computer technologies, such as GIS, RS, 3D model building, virtual reality and etc., and establish the virtual comparison body of actual lower Yellow River in the computer- “Interactive 3D Visual Platfor

17、m of the Lower Yellow River”, on which many application systems, such as flood control, water operation, construction and management of projects and so on, can be developed and applied, which will not only make the platform visually and systematically reflect the basic situation of the flood control

18、 project and also provide planning and construction management of the flood control project, flood control and water dispatch in the lower reach with an all-round visual service platform for application so as to offer a mighty 3D visual decision support environment for the control and development of

19、 the Lower Yellow River. III Contents and Results of Research The scope of the “Interactive ThreeDimensional Visual System of the Lower Yellow River” covers Xiaolangdi on Yellow River, riverway of over 900 kilometers to Yellow Rivers entrance to the sea. The system adopts 3D technologies to realisti

20、cally represent tens of thousands of projects and features, such as the lower reaches of the Yellow River, Xiaolangdi Hydro project, the levee near Lower Yellow River, vulnerable spots, control and training project, guard dam, dyke strengthening by warping project, various culvert gates, bridges, Ye

21、llow River bureaus, flood prevention storehouse, villages and so on, and tens of thousands of non-projects and surface features, such as trees, marks and etc. In the 3D virtual environment provided by the system, we not only can comprehensively research and view the integral layout of the whole Lowe

22、r Yellow River project from a macro perspective, visually know the function of each project and the interrelationships between projects, between the upper and lower reaches, the left and right banks; but also can interactively control, browse and view a certain project from different perspectives at

23、 a close distance, easily and quickly inquire the attributes information of projects and systematically know the operating conditions of projects construction. The user interface of the “Interactive ThreeDimensional Visual System of the Lower Yellow River” refers to Chart 1 as follows: Chart 1: The

24、user interface of the “Interactive ThreeDimensional Visual System of the Lower Yellow River”The whole system is mainly composed of interactive 3D visual Platform, virtual 3D scene and system database with the functions and characteristics of effectiveness of mass 3D data management, the adaptability

25、 of the data updating, the quickness of interactive control, browse and query of the mass 3D scene, the diversity of attribute data representation, the combination of 3D scene GIS analysis with other application systems of “Digital Yellow River”, etc. For the first time, the system realized the appl

26、ication of large scale, highly precise 3D virtual technologies in the field of water conservancy. There is some innovation mainly in the following aspects: (i) For the first time, the system employed the technologies of geographic information system (GIS), virtual reality, 3D model building and data

27、base management to make all the data relevant to the lower reach of Yellow River input into the computer and establish the virtual comparison body of the whole Lower Yellow River- 3D digital platform of the Lower Yellow River. (ii) The system, for the first time, realized the effective management of

28、 the mass data. The “Interactive ThreeDimensional Visual System of the Lower Yellow River” manages and represents the riverway scene of over 900 kilometers below Xiaolangdi in the Lower Yellow River to the Yellow Rivers entrance to the sea, and visually represents the flood control projects, such as

29、 control and training projects, vulnerable spots, guard dam, culvert gates, embankment as well as features, such as flood control and drought relief institution, bridges. The 3D visual system of the Lower Yellow River with such large scale, high precision and overall functions is the precedent in th

30、e field of water conservancy over the country even in the world. (iii) Under mass 3D environment, the system, for the first time, realized the multi-resolution and high precision satellite image as well as nested function of the terrain-data. (iv) The system, for the first time, developed various co

31、mbination browse and inquiry modes under 3D environment, such as interaction control, flying along the line, project positioning, flying positioning and etc. and can quickly and interactively control and browse, inquire and position the mass scene, which makes the scene instantly and exactly positio

32、n any projects or features, to easily and quickly inquire attributes information of projects and features. (v) The system, for the first time, developed the analysis function of dynamic souring and silting of the riverway section by which the system can dynamically render of riverway section over ye

33、ars and represent the process of the souring and silting variation in the riverway section to analyze and study the laws of the souring and silting variation in the riverway. IV Research on system applicationThe completed interactive 3D visual system of the Lower Yellow River is a virtual 3D digital

34、 system, on which a second development can be made, with mass data information and visual representation, based on geographic coordinate control, can be quickly and easily operated as well as strong 3D inquiry and analysis function. And it can provide support in the following aspects for the control

35、 and development of the lower reaches of the Yellow River: (i) The system provided a platform for knowing, understanding and studying the Yellow River. The system offered respectively corresponding 3D scene, projects and features with the actual lower Yellow River and, meanwhile, established relatio

36、ns with project attributes information of which the details can be inquired by pointing and clicking. The quick and easy interactive control browse mode and the scene representation mode that breaks through vision restriction of investigation on site of the 3D system can make users fully and systema

37、tically survey and research the whole lower Yellow River from both macro and micro views, and also can provide much stronger information support than 2D system. Simultaneously, functions of analysis of riverway section, drawing of the terrain section based on 3D scene, area measure and calculation,

38、and distance measurement offered by the system can provide necessary technical methods for understanding and studying the whole lower Yellow River. It is quick to know, understand and study the lower Yellow River through this platform, which provides an overall, systematical, visual research and ana

39、lysis platform for the control and development of the lower Yellow River. (ii) Providing a visual decision support platform for the flood prevention in the Lower Yellow RiverThe working and dangerous condition discussion system can be developed and applied, and the 3D visual working and dangerous co

40、ndition discussion system can be established on the system platform. 2D flood routing model based on GIS may be developed and applied on the “digital virtual” platform established, which can provide visual decision support for the lower Yellow River flood prevention. We can utilize advanced measurin

41、g technologies to measure the lower reaches of the Yellow River and modify the digital elevation mode of the “digital virtual” platform, and then form and simulate the prepared scheme of flood operation on the virtual platform. We can simulate the evolution of flood processes with different levels,

42、causes and project conditions on the platform so that, on the digital virtual platform, we can visually see the flood evolution process of different levels in the riverway. According to the results of flood evolution, we can make withdrawal plan for people in the downstream floodplain or other effec

43、tive emergency measures under different flood levels; and, for the projects that dangerous conditions may appear, make sure that how long it will take to make goods, materials, manpower, machinery, equipment and so on for emergency. When some level flood happens, we start the corresponding flood ope

44、ration scheme, perform real time flood routing, visually represent flood routing process and make a visual emergency operation command through digital platform; when emergency happens in some project, we can point and click the project on the 3D platform to find the emergency treatment scheme of the

45、 project, and make a visual emergency operation command for a definite object in such manners to turn passive flood prevention into active flood prevention to lessen the loss of the lower Yellow River caused by the flood disaster to the least. (iii) Providing a visual application service platform fo

46、r water dispatching management Through the 3D virtual platform provide by the system, we can visually look over the detailed attributes information of every culvert gate on the Yellow River and know the operation of every project. To apply the remote monitoring system of the culvert gate, we can vis

47、ually control the water diversion process through different gates under virtual 3D environment so as to improve the level of water dispatching management.(iv) Providing a working platform for planning, construction and management of flood prevention projects on the lower Yellow RiverThrough the 3D v

48、irtual platform provided by the system, we can visually and systematically observe the projects distribution in the lower Yellow River, and see that on which reach the project spotting is insufficient, or the completed project is not perfect enough. The evolution law concerning river regime may be obtained by the aid of dynamic renewal of satellite image, where the frequent uplifting and down going of river regime can not be well controlled, this system may directly have a layout of node disposal and the up-extension and down-succeeding of the pro