طراحي و اجراي وب اپليكيشن مسير يابي سه بعدي در فضاهاي داخلي

designing and implementing a 3D indoor navigation web application

با توجه به وسيع تر و پيچيده ­تر شدن فضاي بسته داخل ساختمان ­ها مانند فرودگاه­ ها، مراكز خريد و بيمارستان­ ها نياز به سيستم هاي ناوبري در فضاي بسته (Indoor) جهت راهنمايي كاربر مخصوصا در مواقع بحران مانند زلزله و آتش سوزي احساس ميشود. هدف اصلي اين پژوهش طراحي و پياده­سازي سيستم تحت وب ناوبري در فضاي سه ­بعدي داخل ساختمان است. اين سيستم بطور اتوماتيك مدل داده CityGML را پردازش كرده، و اطلاعات مفهومي، توپولوژي و ژئومتري مانند، پلان طبقات، كاربري فضاهاي داخلي و نحوه اتصال اين فضا­ها را از آن استخراج و سپس يك گراف مسيريابي از اطلاعات استخراج شده توليد مي­كند. پردازش مدل داده CityGML و آناليز گراف و مسيريابي در سمت سرور و با استفاده از زبان برنامه­نويسي Python انجام شده، و رابط كاربري نيز با استفاده از زبان­ هاي توسعه وب مانند HTML، JavaScript، JQuery و AJAX توسعه يافته ­است. از ويژگي­هاي اين وب اپليكيشن، ارائه مسير و مدل سه­بعدي ساختمان در يك محيط سه ­بعدي است كه با استفاده از كره مجازي Cesium ايجاد شده و علاوه بر آن به همراه مسير محاسبه شده يك راهنماي توصيفي نيز در اختيار كاربر قرار مي گيردكه باعث درك بهتر از مسير شده­است. انجام اتوماتيك پردازش مدل داده CityGML و توليد گراف و مسيريابي، توسط موتور نرم ­افزاري توسعه داده شده در اين پژوهش باعث شده تا نيازي به استفاده از هرگونه نرم ­افزار جانبي براي اين گونه محاسبات نباشد. امكان اجراي اين نرم ­افزار روي هر وسيله ­اي كه به شبكه اينترنت متصل و مجهز به يك مرورگر رايج وب باشد، وجود دارد.

Nowadays, due to the complexity of interior space of buildings, the need arises for indoor navigation inside such spaces. Indoor navigation systems may be helpful for emergency evacuation of the crowd in natural hazards such as earthquake as well as human-made disasters. These systems can also act as a decision support system for officials. Literature survey on indoor navigation services shows that a large number of researches have been conducted around designing and implementing such systems but automatic indoor spaces topology extraction of the current building information models remains as a challenge. This research aims to introduce, design and implement a web-based indoor navigation system using CityGML data model in LOD4 (level of detail) to overcome the mentioned problem. The architecture of the current research is a browser-based web application service such that the data model processing and graph creation is implemented on the server side, the client interface and calculated path are represented on the client side (browser). Through the CityGML data model processing, firstly, the building navigable spaces such as room floor, doors and stairs are extracted and then, each space as a node and the connections between the nodes are defined as edges, are imported to the navigation graph. Programming on the server side has been performed by Python language and web development languages including HTML (Hypertext Markup language), JavaScript, JQuery and AJAX are used on the client side. Cesium virtual globe has been exploited to display the data model and the calculated route. To evaluate the introduced methodology and designed service, a three floor house with CityGML format in LOD4 was used as the case study. Generally, a client can request a 3D calculated path by selecting the source and destination points on the client browser. The server receives the request and returns the response as a 3D line to the client browser on the Cesium environment. In addition, a descriptive graphical user interface for visual inception of the route is offered to the users on their browser. One of the advantages of the designed web application is that, the service is implemented on the browser. Hence, all devices equipped with a browser have possibility to run the 3D routing service. Besides the mentioned cross-platform capability, average expectation time of the graphical interface loading, data module processing and path finder module are 7.03 milliseconds, 12.42 seconds and 2.44 seconds respectively that visits a valuable criteria in emergency situations like an earthquake phenomenon. Regarding this fact that CityGML is a new data model and supported by a few software, the introduced architecture causes less implementation costs as well as automation of these systems.