Research On Key Technology Of Pedestrian Navigation In Forest Region

Forests are the largest ecosystem on the Earth,containing a lot of natural resources and playing important ecological functions.In different historical periods,forest region is one of the indispensable activity area for people.Walking is an important movement state in forest region.As the forest region is often located remotely,the terrain and landscape are complex,traffic is inconvenient and communication is difficult.Besides,the population is sparse,economy and culture are relatively backward.The forestry employees are less efficient and usually facing with danger.At the same time,there are many times when the people gets lost,trapped and distress.With the increasing number of public incidents in forest region,the situation of rescue work is complicated and severe.Therefore,in the new period,there is an urgent need for accurate,efficient and intelligent pedestrian navigation in forests.With the development of mobile Internet and mobile devices,various types of pedestrian navigation applications have emerged.However,as the lack of consideration of the particularity of pedestrian navigation in forest region,these applications have limitations in conceptual model,map data and operating environment,are not able to be used for navigating in forest region.To solve the above problems,this paper studied the basic theory and key technology of pedestrian navigation in forest region.The main research contents are as follows:(1)The problems and deficiencies in the study of pedestrian navigation in forest region is discussedThrough summarizing the researches of navigation theory and related techniques,the reasons why the existing methods can not solve the pedestrian navigation problem in forest region are as follows:a)the limitation of the navigation concepts,b)the contradiction of existing technologies for solving pedestrian navigation problem in forest region.The objectives of this research are established.These include establishing basic theory and technical framework,exploring key techniques and conducting applied research of the pedestrian navigation in forest region.(2)The basic theory and technology architecture is studieda)The basic theory of pedestrian navigation in forest region is discussed.First,the related basic concepts are accurated.Second,the the characteristics and connotations are proposed.Third,the general process of pedestrian navigation in forest region is abstracted.b)The technology architecture of pedestrian navigation system in forest region is proposed,and the application scenarios are discussed based on the results of the basic theory research.Then the technical requirements for related functions and key technical issues that need to be urgently solved are proposed.(3)The key techniques of pedestrian navigation in forest region based on vector data structure are studieda)Approach for generating pedestrian network in forest region based on improved navigation graph is proposed.First,walking environment is regarded as the space with obstacles.Second,the generation method and optimization method of navigation points are proposed,and the generation algorithm of navigation edges based on the dynamic cone-shaped sweep is proposed to generate sparse navigation graph.This approach can realize effective modeling of open space by vector data.The improved navigation graph can mix existing road network to form the pedestrian network in forest region.b)Approach for descripting vector walking path in forest region using natural language is proposed.First,landmarks are used as guide cues,and the reference relationship between spatial objects is established by constructing visuable area of landmarks.On this basis,the global and local path description algorithm are proposed,optimal path is output as textual description consisting of the sequence information between consecutive landmarks and the behavior requirements associated therewith.(4)The key techniques of pedestrian navigation in forest region based on raster data structure are studieda)Optimal Walking Path Analysis Method for Forest Region(OWPAM-FR)is proposed.First,introducing the concept of walkability,the pedestrian environment in the forest region is qualitatively divided into walkable area,unwalkable area,and easy-to-walk area.Second,Comprehensive Walkability Raster(CWR)is defined and constructed to compute comprehensive costs and establish raster network.This method can effectively model the hybrid space of forest region and compute optimal walking path using raster data.b)Approach for descripting raster walking path in forest region using natural language is proposed.First,Raster Route Description Data Model(RRDDM)is established using thematic attribute data of raster route.Second,three-dimensional geometric shape and landmark reference characteristics are extracted to divide the route into several route segments and combine into compound route segments.Third,global and local route description algorthms are proposed,which realize the automatic generation of two kinds of natural language description of the raster route in the forest region.(5)Applied research on key techniques of pedestrian navigation in forest regionJiufeng National Forest Part is taken as stady area in this research.Conbining with the requirements forest management planning and design inventory,Jiufeng Forest Resources Survey System(JF_FRSS)is developed.User types and their needs are analyzed,functions and storage are designed.Then key techniques proposed in this study are realized to build pedestrian navigation subsystem.In this way,the feasibility of key techniques is verified.At the same time,it becomes an example for future technique applications.