Multi-Access Positioning System M.A.P.S

Transcription

1 Multi-Access Positioning System M.A.P.S UCD Multi-Access Positioning System EEC173B Winter 2006 Ting (Randy) Chang Michael Hsu Alex Sung George Louie (MIA) 1

2 Introduction and Motivation Introduction Cartography I Importance of Cartography in History - Territorial Boundaries - Trade Routes - Navigation through Maps and Compasses 2

3 Introduction Cartography II Modern Day Map Utilization - Highway and Road Infrastructure - Internet Routing - Travelling on a Global Scale - Still navigation through some sort of map Introduction Cartography III How it Applies to UC Davis - Large Campus - Disorganized infrastructure - No Civil Planning involved! - High Student Traffic - It is an Urban Labyrinth! 3

4 Introduction Motivation I UCD Lacks Efficient Logistics Services Current existing services: - MU Info Booth - UCD Planner & Unitrans Maps - Street Signs and Maps - On-Line Campus Map None of which offers strong dynamic and easily-accessible routing services. Introduction Motivation II Commercial Products Lack Detail Current Digital Maps: -Google Map -Yahoo Map -MapQuest -Virtual Campus 4

5 Introduction Thoughts We want a system that... - updates users with the latest map. - clients may use to route paths. - works outdoors and indoors - maps building internals. - has traffic analysis. Previous Work How we used to do it 5

6 Previous Works Paper Maps Paper Map Flaws: - Easy to lose and destroy - Static must buy a new one to obtain new information - You calculate a route yourself - Waste of paper! - Clumsy to carry around Previous Works Info Booth Info Booth, Street Sign Flaws: - Need to find the booth or signs - Limited scope of information - Info booth inconvenience - Street signs not widely available - No real-time dynamic guiding 6

7 Previous Works Digital Map Digital Map Flaws - Too general - No details regarding campus - No mapping within buildings - Update only once in a while - Potentially incorrect Related Work What s similar 7

8 Related Work Campus Navigator I By University of Washington and Chinese University of Hong Kong Goal: How can we help a person in an unfamiliar setting Designed to be user-friendly, resource efficient, and has user navigation Related Work Campus Navigator III Location Awareness - Utilize both GPS and WLAN to determine position indoors and outdoors Speech User Interface - Speech Language Application Tags (SALT) for quick user interface. 8

9 Related Work Active Campus I By UC San Diego Goal: Re-engage users with their surroundings Features - Find out friends that are around - Virtual Bulletin Board - Privacy Control - Interactive class forum Problem and Solution 9

10 M.A.P.S. - Problems I Current Mapping Systems: - Provides routing services - Generic information - Not specific enough for UCD - Very limited mobility - No location awareness M.A.P.S. - Problems II Current Positioning Systems - Adaptability for specific locations - Does not provide routing services - No commercial funding - Features are incomplete - Development is immature 10

11 M.A.P.S. - Solutions - Extend existing incomplete offering - Integrate features into existing platform - Utilize both positioning and routing - Enable real-time tracking of friends (Stalker friendly) - Enable self map update - Limitless possibilities, use imagination! Design 11

12 Design Client GUI Client Graphical User Interface Design Routing Algorithm Dijkstra - Given graph G with nodes N and edges E with weight W - Solves shortest-path problem - Given source and destination, traverse through all nodes keeping track of shortest-path database 12

13 Design Server/Client Model Server/Client Model - Workload shifted to network edge - Basic server functionality - Authentication - Simple Tracking - Provides updates - Full featured client - Route processing Demo 13

14 Implementation Implementation Client GUI Client Graphical User Interface - Java Swing Components - Quick Deployment - Dynamic changeable GUI parts - Platform independent - Uniform look on all system 14

15 Implementation Client GUI Client Graphical User Interface -Abstract Window Toolkit - Customizable Mouse Interface - Built-in geometric functions - Auto-multithreading for GUI Implementation Routing Algorithm I Dijkstra Node.java Node object stores name, id, and (x,y) coordinates relative to map Route.java Route object connecting nodes RoutesMap.java Basic map interface for nodes and routes 15

16 Implementation Routing Algorithm II Dijkstra and Map Reader API DijkstraEngine.java Given a map populated with nodes and routes, calculate the shortestpath database map_reader.java Interface between GUI and Dijkstra Given a source, destination, and map, will run the Dijkstra Engine on that map Implementation Routing Algorithm II Map Object gmap.java Interface object representing a map passed between server and client Stores data essential to a map such as the picture, nodes, routes, location name, etc. map_wellman.java Sample map implementing gmap 16

17 Implementation Server/Client Model Server/Client Model Core components: Listener.java Module for listening on a specified port. Generic.java Interface for software development. Implementation Server/Client Model Server/Client Model Server: Server.java Passive design, responds to incoming queries by clients. Client: Client.java Active and passive design. Potential for a p2p network. 17

18 Results and Evaluation Results Results of Study on Placelab technology - Placelab relies on triangulation of 3 or more APs. - Low precision due to constant changing SNR. -Lack of sufficient wireless APs for practical usage -Triangulation MUCH slower than GPS 18

19 Results Results of Study on Placelab technology -Is Placelab feasible? -Most home/private APs aren t reliable -Home APs are not fixed in location! -I change my router once every week!!! -I change my router MAC address every month. Results Results of Study on Placelab technology -Is Placelab feasible? -Intel PlaceLab database incompatible for customized developer uses -Different coordinate system -Difficult translation -Not platform independent (due to the driver part for wireless) 19

20 Results Results of Study on Placelab technology -Is Placelab feasible? -Wireless n is on the horizon -10x more square area coverage than b/g -Less fixed APs are needed in the future -Can t triangulate if less than 3 APs Results Results of Study on GPS -Most GPS system not open-source! -Not compatible with Java, thus not platform independent -GPS lack accuracy, 30 meters off (intentionally by US government) -US GPS Satellite are 30 years old! -Security issue!! Government controlled network! 20

21 Results Results of Study on Wireless Network -Coverage is sparse, limited availability to get on internet. -Many APs has NAT and firewall, difficult for developer to integrate -Many socket restrictions Evaluation - Analysis -Need better positioning module -Do not need to re-invent the wheel, just improve it -Extends features to existing technologies -Need more people mapping! -Most difficult part is mapping! Coding took only a few days, mapping takes weeks 21

22 Future Focus Expand to Rest of Davis - Map apartments, shops, etc Unitrans and Yolobus Integration - Map routes, arrivals, departures Traffic Analysis - Add weight to paths based on amount of people on it Future Focus II Event Tracking - Register local events by time and location - Users may search for events to map a path to. Placelab Integration - Find user location based on WLAN 22

23 References References Campus Navigator Active Campus Dijkstra Implementation Renaud GUI Scrolling Santhosh Kumar T, 23