scholarly journals Ontology based Indoor Navigation Service for the ILONA System

2018 ◽  
pp. 20-29
Author(s):  
Dániel Péter Kun ◽  
Erika Baksáné Varga ◽  
Zsolt Tóth

An ontology based way finding algorithm is presented in this paper that allows route generation between two separate parts of an indoor environment. The presented ontology provides a flexible way to describe and model the indoor environment, in addition it fits and extends the existing model of the ILONA System. Ontology reasoners provide an efficient way to perform complex queries over the knowledge base. The instances, that are queried by the reasoner, are used to initialize the graph which represents an indoor environment. Due to parameterization of the reasoner, different graphs can be generated from the ontology which makes the way finding algorithm flexible. Thus, the task of indoor way finding was converted into a well-known graph search problem. Dijkstra’s shortest path algorithm is used for route generation in the graph yielded. The algorithm was implemented and tested in the ILONA System and its functioning is demonstrated by real-life scenarios.

Symmetry ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 421
Author(s):  
Mina Asaduzzaman ◽  
Tan Kim Geok ◽  
Ferdous Hossain ◽  
Shohel Sayeed ◽  
Azlan Abdaziz ◽  
...  

The shortest path-searching with the minimal weight for multiple destinations is a crucial need in an indoor applications, especially in supermarkets, warehouses, libraries, etc. However, when it is used for multiple item searches, its weight becomes higher as it searches only the shortest path between the single sources to each destination item separately. If the conventional Dijkstra algorithm is modified to multi-destination mode then the weight is decreased, but the output path is not considered as the real shortest path among multiple destinations items. Our proposed algorithm is more efficient for finding the shortest path among multiple destination items with minimum weight, compared to the single source single destination and modified multi-destinations of Dijkstra’s algorithm. In this research, our proposed method has been validated by real-world data as well as by simulated random solutions. Our advancement is more applicable in indoor environment applications based on multiple items or destinations searching.


2009 ◽  
Vol 113 (1143) ◽  
pp. 301-308 ◽  
Author(s):  
R. Zardashti ◽  
M. Bagherian

Abstract This paper focuses on the three dimensional flight path planning for a UAV on a low altitude terrain following/terrain avoidance mission. Using an approximate grid-based discretisation scheme, we transform the continuous optimisation problem into a search problem over a finite network, and apply a variant of the shortest-path algorithm to this problem. In other words using the three dimensional terrain information, three dimensional flight path from a starting point to an end point, minimising a cost function and regarding the kinematics constraints of the UAV is calculated. A network flow model is constructed based on the digital terrain elevation data (DTED) and a layered network is obtained. The cost function for each arc is defined as the length of the arc, then a constrained shortest path algorithm which considers the kinematics and the altitude constraints of the UAV is used to obtain the best route. Moreover the important performance parameters of the UAV are discussed. Finally a new algorithm is proposed to smooth the path in order to reduce the workload of the autopilot and control system of the UAV. The numeric results are presented to verify the capability of the procedure to generate admissible route in minimum possible time in comparison to the previous procedures. So this algorithm is potentially suited for using in online systems.


2019 ◽  
Vol 1 ◽  
pp. 1-2
Author(s):  
Nina Vanhaeren ◽  
Kristien Ooms ◽  
Philippe De Maeyer

<p><strong>Abstract.</strong> Wayfinding in the indoor environment is challenging and people often get lost indoors. Navigation systems guide people in these environments, however, the existing systems are not well adapted to their users. The focus of our research is on the route planning aspect of navigation systems. By adapting the routes that people are guided along in the environment, our goal is to substantially improve the wayfinding experience for the users of those systems. Guiding people along routes that adhere better to their cognitive processes could ease the wayfinder in the indoor environment.</p><p>To select the aspects that should be implemented in a routing algorithm that calculates such routes, a mixed method approach was applied. In this approach, the results of an exploratory focus group and a complementary online survey were combined. To validate these results, a real-life experiment is being developed at the time of writing.</p><p>Our first study, the exploratory focus group, comprised academic researchers and experts with different background (i.e. Psychology, Geography and Architectural Design). The discussions were guided by a rotating wheel according to the GPS-method which was developed by the Flanders District of Creativity. These discussions provided a broad overview of the elements to be regarded when studying wayfinding. Moreover, results indicate that route complexity has to be considered at different levels: local level (i.e. at decision points) and global level (i.e. legibility of the building). Based on the results of the focus group, multiple situations with specific local characteristics likely inducing confusion and discomfort (e.g. specific intersections, different stair cases, different door types) were selected to elaborate more deeply in the complementary online survey. In this survey, videos of these situations were shown to the participants, as if they were navigating through the building. They were asked to rank their comfort and confusion level about the recorded situation on a 5-point Likert-scale. The results show that visibility, visual clutter and geometric simplicity are of substantial importance when evaluating comfort and confusion levels, and thus the complexity of indoor navigation situations.</p><p>Since body-movement and the real-world perceptions, which have a substantial impact on information processing and spatial decision making [1], are excluded in these well-controlled lab environments of the previous studies, a real-life experiment will be executed to validate previous findings. The developed study design is in line with the experiment design of previous wayfinding studies [2], [3]. Eye tracking data of participants guided through different complex buildings along different paths (i.e. shortest path and fewest turn path) will be recorded. Performance measures (e.g. duration, stops, errors), eye tracking measures (e.g. fixation number, fixating duration) and annotations of the accompanying researcher, which are all measures indicating complexity and cognitive load, will be compared across the different paths and its decision points. This analysis will allow us to determine complex routes and to identify the environmental characteristics increasing the perceived complexity. Moreover, it will lead to an understanding how and in which occasions people make wayfinding errors.</p><p>In a subsequent phase of our research project, these results will be incorporated in a cognitively-sounding route planning algorithm which could be a valuable improvement of indoor navigation support. Focus will be on the theoretical interpretation of the underlying spatial concepts. Adjusting the route planning support of indoor navigation systems to human wayfinding behavior could be a substantial contribution in this area.</p>


2009 ◽  
Vol 419-420 ◽  
pp. 557-560 ◽  
Author(s):  
Rui Li

Shortest path is the core issue in application of WebGIS. Improving the efficiency of the algorithm is an urgent requirement to be resolved at present. By the lossy algorithm analyzing, which is the current research focus of the shortest path algorithm to optimize, utilizing adjacency table of storage structures, restricted direction strategy and binary heap technology to optimize the algorithm, thereby reduce the scale of algorithm to improve the operating efficiency of algorithm. This scheme has been applied in the simulation of the data downloaded from the Guangdong Provincial Highway Network Information System and satisfactory results have been obtained.


2016 ◽  
Vol 49 (12) ◽  
pp. 532-537
Author(s):  
A. Cano-Acosta ◽  
John Fontecha ◽  
Nubia Velasco ◽  
Felipe Muñoz-Giraldo

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