Patent Publication Number: US-2006004514-A1

Title: Method of collecting information for a geographic database for use with a navigation system

Description:
REFERENCE TO RELATED APPLICATIONS  
      The present application is related to the co-pending application entitled “METHOD OF COLLECTING INFORMATION FOR A GEOGRAPHIC DATABASE FOR USE WITH A NAVIGATION SYSTEM” filed on the same date herewith, Attorney Docket No. N0181US, the entire disclosure of which is incorporated by reference herein. The present application is related to the co-pending application entitled “METHOD OF OPERATING A NAVIGATION SYSTEM” filed on the same date herewith, Attorney Docket No. N0183US, the entire disclosure of which is incorporated by reference herein. The present application is related to the co-pending application entitled “METHOD OF COLLECTING INFORMATION FOR A GEOGRAPHIC DATABASE FOR USE WITH A NAVIGATION SYSTEM” filed on the same date herewith, Attorney Docket No. N0192US, the entire disclosure of which is incorporated by reference herein. The present application is related to the co-pending application entitled “METHOD OF OPERATING A NAVIGATION SYSTEM USING IMAGES” filed on the same date herewith, Attorney Docket No. N0193US, the entire disclosure of which is incorporated by reference herein. The present application is related to the co-pending application entitled “METHOD OF COLLECTING INFORMATION FOR A GEOGRAPHIC DATABASE FOR USE WITH A NAVIGATION SYSTEM” filed on the same date herewith, Attorney Docket No. N0194US, the entire disclosure of which is incorporated by reference herein.  
     BACKGROUND OF THE INVENTION  
      The present invention relates to a method and system for collecting information for a geographic database, and more particularly to a method and system for collecting pedestrian-related information for a geographic database.  
      Vehicle navigation systems are available that provide end users with various navigation-related functions and features. For example, some navigation systems are able to determine an optimum route to travel along a road network from an origin location to a destination location in a geographic region. Using input from the end user, and optionally from equipment that can determine the end user&#39;s location (such as a GPS system), the navigation system can examine various potential routes between the origin and destination locations to determine the optimum route. The navigation system may then provide the end user with information about the optimum route in the form of guidance that identifies the driving maneuvers required to be taken by the end user to travel from the origin to the destination location. The guidance may take the form of visual and/or audio instructions that are provided along the way as the end user is traveling the route. Some navigation systems are able to show detailed maps on displays outlining the route, the types of maneuvers to be taken at various locations along the route, locations of certain types of features, and so on.  
      In order to provide these and other navigation-related functions and features, navigation systems use geographic data. The geographic data may be in the form of one or more geographic databases that include data representing physical features in the geographic region. The geographic database includes information about the represented geographic features, such as the positions of the roads, speed limits along portions of roads, address ranges along the road portions, turn restrictions at intersections of roads, direction restrictions, such as one-way streets, and so on. Additionally, the geographic data may include points of interest, such as restaurants, hotels, airports, gas stations, stadiums, police stations, and so on.  
      Although navigation systems provide many important features, there continues to be room for new features and improvements. One area in which there is room for improvement relates to determining a route for a pedestrian and to providing guidance to the pedestrian following the route. Pedestrian routes and guidance provides challenges not associated with vehicle guidance. Pedestrians are not limited to travel only on the road network; rather, pedestrians may walk through public spaces, such as plazas and parks, having no associated road network. Additionally, pedestrians do not have direction restrictions as a vehicle; pedestrians can walk down a one-way street in both directions. Moreover, pedestrians have a greater degree of freedom of motion and may become more frequently confused as to their orientation to destination.  
      Accordingly, it would be beneficial to have a way to collect information that may be used to provide improved navigation-related functions and features to pedestrians and other users.  
     SUMMARY OF THE INVENTION  
      To address these and other objectives, the present invention comprises a method for collecting data for a geographic database for use with a navigation system. The method identifies a pedestrian segment associated with a path. A text description of the pedestrian segment is collected. The text description includes one of a predetermined number of phrases and a name of at least one feature visible from a location of the segment. The method stores data in the geographic database that represent the pedestrian segment.  
      Another aspect of the present invention is a geographic database that represents features in a geographic region. The geographic database comprises data representing a path in the geographic region. The data representing the path comprises data representing a name of at least one feature visible from a location on the path and data representing one of a predetermined number of phrases associated with the name of the visible feature. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      An exemplary embodiment of the present invention is described herein with reference to the following drawings.  
       FIG. 1  is a block diagram of a navigation system, according to an exemplary embodiment.  
       FIG. 2  illustrates a map of a geographic region.  
       FIG. 3  is a block diagram of a geographic database included in the navigation system depicted in  FIG. 1 , according to an exemplary embodiment.  
       FIG. 4  is a block diagram of components of data records contained in the geographic database depicted in  FIG. 3 , according to an exemplary embodiment.  
       FIG. 5  is a representation of a portion of the geographic region depicted in  FIG. 2 , according to an exemplary embodiment.  
       FIG. 6  is a flow chart for collecting pedestrian information for unorganized geographic areas, according to an exemplary embodiment.  
       FIG. 7A  is a representation of a plaza.  
       FIG. 7B  is a representation of the plaza of  FIG. 7A  containing virtual pedestrian segments, according to an exemplary embodiment.  
       FIG. 8  is a flow chart collecting pedestrian information for organized geographic areas, according to an exemplary embodiment.  
       FIG. 9A  is a flow chart for collecting pedestrian text route guidance information, according to an exemplary embodiment.  
       FIG. 9B  is a representation of a portion of a train station.  
       FIG. 10  is a block diagram of components of pedestrian segment and orientation node data records, according to an exemplary embodiment.  
       FIG. 11  is a table of pedestrian segment data records in the geographic database, according to an exemplary embodiment.  
       FIG. 12  is a table of orientation node data records in the geographic database, according to an exemplary embodiment.  
       FIG. 13  is a block diagram of components of a pedestrian text route guidance data record, according to an exemplary embodiment.  
       FIG. 14  is a block diagram illustrating components of the output of a route calculation function, according to an exemplary embodiment.  
       FIG. 15  is a flow chart for creating a pedestrian guidance message, according to an exemplary embodiment.  
      FIGS.  16 A-D is a flow chart that depicts a more detailed method of constructing the pedestrian guidance message as the depicted in  FIG. 15 , according to an exemplary embodiment.  
       FIGS. 17A and 17B  provide examples of creating pedestrian guidance messages, according to an exemplary embodiment.  
       FIGS. 18A, 18B  and  18 C are screen shots of pedestrian guidance messages a pedestrian may receive using the navigation system of  FIG. 1 .  
    
    
     DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS  
      I. Navigation System  
       FIG. 1  is a block diagram of a navigation system  100  associated with a computing platform  102 , such as a personal digital assistant (PDA), mobile telephone or any other computer, according to an exemplary embodiment. The navigation system  100  is a combination of hardware and software components. In one embodiment, the navigation system  100  includes a processor  104 , a drive  106  connected to the processor  104 , and a non-volatile memory storage device  108  for storing navigation application software programs  110  and possibly other information.  
      The navigation system  100  also includes a positioning system  112 . The positioning system  112  may utilize GPS-type technology, a dead reckoning-type system, or combinations of these or other systems, all of which are known in the art. The positioning system  112  may include suitable sensing devices that measure the traveling distance speed, direction, orientation and so on. The positioning system  112  may also include a GPS system. The positioning system  112  outputs a signal to the processor  104 . The navigation application software programs  110  that run on the processor  104  use the signal from the positioning system  112  to determine the location, direction, orientation, etc., of the computing platform  102 .  
      The navigation system  100  also includes a user interface  114  that allows the end user to input information into the navigation system  100  and obtain information from the navigation system  100 . The input information may include a request for navigation features and functions of the navigation system  100 . To provide navigation features and functions, the navigation system  100  uses a geographic database  116  stored on a storage medium  118 . In one embodiment, the storage medium  118  is installed in the drive  106  so that the geographic database  116  can be read and used by the navigation system  100 . In one embodiment, the geographic database  116  may be a geographic database published by NAVTEQ North America, LLC of Chicago, Ill. The storage medium  118  and the geographic database  116  do not have to be physically provided at the location of the navigation system  100 . In alternative embodiments, the storage medium  118 , upon which some or the entire geographic database  116  is stored, may be located remotely from the rest of the navigation system  100  and portions of the geographic data provided via a communications system  120 , as needed.  
      In one exemplary type of system, the navigation application software programs  110  load from the non-volatile memory storage device  108  into a random access memory (RAM)  122  associated with the processor  104 . The processor  104  also receives input from the user interface  114 . The navigation system  100  uses the geographic database  116  stored on the storage medium  118 , possibly in conjunction with the outputs from the positioning system  112  and the communications system  120 , to provide various navigation features and functions. The navigation application software programs  110  may include separate applications (or subprograms) that provide the various navigation-related features and functions. The navigation functions and features may include route calculation  124  (wherein a route from an origin to a destination is determined), route guidance  126  (wherein detailed directions are provided for reaching a desired destination), map display  128 , and positioning  130  (e.g., map matching).  
      Other functions and programming  132  may be included in the navigation system  100 . The navigation application software programs  110  may be written in a suitable computer programming language such as C, although other programming languages, such as C++ or Java, are also suitable. All of the components described above may be conventional (or other than conventional) and the manufacture and use of these components are known to those of skill in the art.  
      II. Geographic Database  
      In order to provide navigation-related features and functions to the end user, the navigation system  100  uses the geographic database  116 . The geographic database  116  includes information about one or more geographic regions.  FIG. 2  illustrates a map  200  of a geographic region  202 . The geographic region  202  may correspond to a metropolitan or rural area, a state, a country, or combinations thereof, or any other area. Located in the geographic region  202  are physical geographic features, such as roads, points of interest (including businesses, municipal facilities, etc.), lakes, rivers, railroads, municipalities, etc.  
       FIG. 2  also includes an enlarged map  204  of a portion  206  of the geographic region  202 . The enlarged map  204  illustrates part of a road network  208  in the geographic region  202 . The road network  208  includes, among other things, roads and intersections located in the geographic region  202 . As shown in the portion  206 , each road in the geographic region  202  is composed of one or more road segments  210 . A road segment  210  represents a portion of the road. Each road segment  210  is shown to have associated with it two nodes  212 ; one node represents the point at one end of the road segment and the other node represents the point at the other end of the road segment. The node  212  at either end of a road segment  210  may correspond to a location at which the road meets another road, i.e., an intersection, or where the road dead-ends.  
      Referring to  FIG. 3 , the geographic database  116  contains data  302  that represents some of the physical geographic features in the geographic region  202  depicted in  FIG. 2 . The data  302  contained in the geographic database  116  includes data that represent the road network  208 . In the embodiment of  FIG. 3 , the geographic database  116  that represents the geographic region  202  contains at least one road segment database record  304  (also referred to as “entity” or “entry”) for each road segment  210  in the geographic region  202 . The geographic database  116  that represents the geographic region  202  also includes a node database record  306  (or “entity” or “entry”) for each node  212  in the geographic region  202 . The terms “nodes” and “segments” represent only one terminology for describing these physical geographic features, and other terminology for describing these features is intended to be encompassed within the scope of these concepts.  
      The geographic database  116  may also include other kinds of data  312 . The other kinds of data  312  may represent other kinds of geographic features or anything else. The other kinds of data may include point of interest data. For example, the point of interest data may include point of interest records comprising a type (e.g., the type of point of interest, such as restaurant, hotel, city hall, police station, historical marker, ATM, golf course, etc.), location of the point of interest, a phone number, hours of operation, etc. The geographic database  116  also includes indexes  314 . The indexes  314  may include various types of indexes that relate the different types of data to each other or that relate to other aspects of the data contained in the geographic database  116 . For example, the indexes  314  may relate the nodes in the node data records  306  with the end points of a road segment in the road segment data records  304 . As another example, the indexes  314  may relate point of interest data in the other data records  312  with a road segment in the segment data records  304 .  
       FIG. 4  shows some of the components of a road segment data record  304  contained in the geographic database  116 . The road segment data record  304  includes a segment ID  304 ( 1 ) by which the data record can be identified in the geographic database  116 . Each road segment data record  304  has associated with it information (such as “attributes”, “fields”, etc.) that describes features of the represented road segment. The road segment data record  304  may include data  304 ( 2 ) that indicate the restrictions, if any, on the direction of vehicular travel permitted on the represented road segment. The road segment data record  304  includes data  304 ( 3 ) that indicate a speed limit or speed category (i.e., the maximum permitted vehicular speed of travel) on the represented road segment. The road segment data record  304  may also include data  304 ( 4 ) indicating whether the represented road segment is part of a controlled access road (such as an expressway), a ramp to a controlled access road, a bridge, a tunnel, a toll road, a ferry, and so on.  
      The road segment data record  304  also includes data  304 ( 6 ) providing the geographic coordinates (e.g., the latitude and longitude) of the end points of the represented road segment. In one embodiment, the data  304 ( 6 ) are references to the node data records  306  that represent the nodes corresponding to the end points of the represented road segment.  
      The road segment data record  304  may also include or be associated with other data  304 ( 7 ) that refer to various other attributes of the represented road segment. The various attributes associated with a road segment may be included in a single road segment record, or may be included in more than one type of record which cross-references to each other. For example, the road segment data record  304  may include data identifying what turn restrictions exist at each of the nodes which correspond to intersections at the ends of the road portion represented by the road segment, the name or names by which the represented road segment is known, the street address ranges along the represented road segment, and so on.  
       FIG. 4  also shows some of the components of a node data record  306  contained in the geographic database  116 . Each of the node data records  306  may have associated information (such as “attributes”, “fields”, etc.) that allows identification of the road segment(s) that connect to it and/or it&#39;s geographic position (e.g., its latitude and longitude coordinates). For the embodiment shown in  FIG. 4 , the node data records  306 ( 1 ) and  306 ( 2 ) include the latitude and longitude coordinates 306(1)( 1 ) and  306 ( 2 )( 1 ) for their node. The node data records  306 ( 1 ) and  306 ( 2 ) may also include other data  306 ( 1 )( 3 ) and  306 ( 2 )( 3 ) that refer to various other attributes of the nodes.  
      III. Collecting Pedestrian Data  
      Referring to  FIG. 2 , the enlarged portion  206  of the illustrated geographic region  202  includes a portion of the road network  208  and a portion of a park  214 . In one embodiment, the navigation system  100  provides navigation-related features and functions to a user operating a motor vehicle, such as a truck, car or motorcycle. For this embodiment, the navigation system  100  utilizes data representing the road network  208  in the geographic database  116  to provide navigation-related features and functions, such as route calculation and route guidance. For example, the route calculation application provides a continuous navigable route from the origin to the destination as an order list identifying a plurality of road segment data entities. The route guidance application provides maneuvering instructions along the road network to follow the calculated route.  
      In another embodiment, the navigation system  100  provides navigation-related features and functions to a user that is not operating a motor vehicle, such as a pedestrian. For this example, the pedestrian is not limited to travel only on the road network  208 . Rather, the pedestrian may walk through public plazas and parks having no associated road network. Additionally, the pedestrian does not have direction restrictions as a vehicle; the pedestrian can walk down a one-way street in both directions. Moreover, the pedestrian has a greater degree of freedom of motion and may become more frequently confused as to their orientation.  
       FIG. 5  illustrates a portion of a park  214  in the geographic region  202  of  FIG. 2 . Suppose the pedestrian requests a route from the navigation system  100  from his or her current position  502  to a cafe  504 . If the navigation system  100  calculated the route using only the road network  208 , the route to the cafe  504  would comprise consecutive road segments  506 ,  508 ,  510  and  512  with left turn maneuvers at nodes  514  and  516 . However, since the pedestrian can walk through the park, a more direct and shorter route is possible. To allow the navigation system  100  to provide improved pedestrian routes, a geographic database developer collects information relating to the geographic features of the geographic region useful for providing pedestrians and other users with navigation-related features and functions. In one embodiment, a geographic researcher travels the geographic region to collect information relating to geographic features useful for providing pedestrians with navigation-related features and functions (hereinafter “pedestrian data”). In another embodiment, the geographic researcher uses aerial images to collect pedestrian data.  
      A. Collecting Pedestrian Data for Unorganized Geographic Areas  
      An unorganized geographic area is a geographic area that lacks underlying organization into paths or roads. That is, the unorganized geographic area does not contain path or road geometry marked by paving, contrasting ground cover, such as a dirt trail through a grassy meadow, or paint trails over concrete. For example, the park illustrated in  FIG. 5 , includes established paths  518  and  520 , paved or unpaved; however, the park also includes an unorganized portion  522  over which the pedestrian may walk without any paths, such as over grassy areas.  
       FIG. 6  is a flow chart  600  for collecting pedestrian data for unorganized geographic areas, according to an exemplary embodiment. The steps of  FIG. 6  will be illustrated using the unorganized geographic area  522  of the park  214  of  FIG. 5 . At step  600 , the geographic researcher identifies a portion of the unorganized geographic area appropriate for a virtual pedestrian network. The virtual pedestrian network is similar to the road network  208 . Whereas the road network  208  comprises of road segments and nodes, the virtual pedestrian network comprises virtual pedestrian segments and orientation nodes. Whereas a vehicle may be routed and guided from an origin to a destination over the road network  208 , a pedestrian or other user may be routed and guided from an origin to a destination over, in part or entirely, the virtual pedestrian network which traverses unorganized geographic area lacking the road network or established paths. In one embodiment, the geographic researcher identifies a portion of the unorganized geographic area appropriate for a virtual pedestrian network by determining that pedestrians may readily traverse the unorganized geographic area, that pedestrians may reduce their travel distance and/or travel time by traversing the unorganized geographic area and/or that pedestrians may desire to be routed and guided to a feature or point of interest within the unorganized geographic area.  
      Once the geographic researcher has identified a portion of the unorganized geographic area appropriate for the virtual pedestrian network, the geographic researcher identifies a series of interconnected virtual pedestrian segments and associated orientation nodes. Each virtual pedestrian segment is associated with two orientation nodes; one orientation node represents one end of the virtual pedestrian segment and the other orientation node represents the other end of the virtual pedestrian segment. The orientation node at either end of the virtual pedestrian segment may correspond to a location at which the virtual pedestrian segment meets another virtual pedestrian segment, where the virtual pedestrian segment meets a road segment, where the virtual pedestrian segment meets a pedestrian segment associated with a path of an organized geographic area, at a point of interest or where the virtual pedestrian segment dead-ends.  
      Referring to  FIG. 6 , at step  602 , the geographic researcher identifies an orientation node. The location of the orientation node is selected at a location that may be readily described to provide orientation to the pedestrian. In one embodiment, the orientation node is selected at a location that may be visually identified by the pedestrian. For the exemplary embodiment illustrated in  FIG. 5 , an orientation node  524  is located near a statue  526 . The statue  526  is a prominent feature readily visually observed by the pedestrian. Additionally, a clear and concise description of the statue  526 , such as statue of a man on a horse, provides orientation to the pedestrian.  
      At step  604 , the researcher collects attribute information of the orientation node. Attribute information includes descriptive words characterizing the location of the orientation node and any surrounding features, such as statue of a man on a horse, for orientation node  524 . The attribute information also may include a latitude and longitude position of the orientation node. A positioning system may be used to determine the latitude and longitude position of the orientation node. The position system may utilize GPS-type technology, a dead reckoning-type system, or combinations of these or other systems, all of which are known in the art. The positioning system may include suitable sensing devices to obtain a GPS signal and to measure the traveling distance speed, direction, and so on, of the system. Alternatively, aerial images of the area may be used to determine the position of the orientation node.  
      Other attribute information of the orientation node that may be collected include: wheel chair accessible, children friendly, pet friendly, well-lighted area, poorly lighted area, busy area, non-busy area, noisy/peaceful, smelly/polluted, sheltered from rain, not sheltered from rain, no bikes allowed, tree lined, paved area, unpaved area, grassy area, gravel area, dirt area, muddy when wet area, and any other attribute information. The geographic researcher may record the attribute information using any data collection method, such as handwriting, voice recording, and data entry into a user device. In one embodiment, the researcher may capture an image of the orientation node including the surrounding area with a digital camera. Furthermore, the researcher may collect guidance information as discussed below in conjunction with  FIG. 8  for the orientation node.  
      In one embodiment, the researcher collects connection information indicating whether the orientation node is in close proximity to the road network  208 . If the orientation node is close to the road network  208 , the researcher identifies the road node close to the orientation node. In another embodiment, the researcher may identify a road segment for connection information. The researcher may record the connection information in the form of a street address, name or ID of a road segment or road node, a distance from a node along an identified road segment, intersection of two identified road segments, a point of interest or in any other appropriate form. For the example depicted in  FIG. 5 , the researcher records connection information identifying that orientation node  524  connects with road segment  506 . If the orientation node is not close to the road network, the researcher records such an indication.  
      At step  606 , the geographic researcher identifies another orientation node. The second orientation node  528  is selected at another location that may be readily described to provide orientation to the pedestrian. Additionally, the second orientation node is selected at a location in which the pedestrian may be directed from the first orientation node location to the second orientation node location. In one embodiment, the second orientation node is selected at a distance from the first orientation node such that the pedestrian may visually identify the location of the second orientation node from the location of the first orientation node. In another embodiment, the second orientation node location may be obscured from view or beyond visual identification from the first orientation node location. For example, the pedestrian may be directed to walk in a certain direction, such as toward a lake, and after walking some distance, the second orientation node comes into view.  
      For the exemplary embodiment illustrated in  FIG. 5 , a second orientation node  528  is located near a barbeque pit  530 . The barbeque pit  530  is a prominent feature readily visually observed by the pedestrian. Additionally, a clear and concise description of the barbeque pit  530 , such as a stone barbeque pit with pizza oven feature, provides orientation to the pedestrian. At step  608 , the researcher collects attribute information of the orientation node in the similar manner as discussed above for the first orientation node  524 .  
      At step  610 , the researcher identifies a virtual pedestrian segment  532 . The virtual pedestrian segment  532  is an artificially created segment over the unorganized portion  522  on which the pedestrian may walk from the first orientation node  524  to the second orientation node  528 . When identifying the virtual pedestrian segments, the geographic researcher insures that the pedestrian may walk unobstructed from the first to the second orientation node. For example, the geographic researcher would not identify a virtual pedestrian segment that goes over a cliff.  
      At step  612 , the researcher collects attribute information of the virtual pedestrian segment. Attribute information includes descriptive words characterizing the virtual pedestrian segment and any surrounding features. For example, virtual pedestrian segment  532  may be described as “keeping the pond on your right/left.” The attribute information may also include a distance or length of the virtual pedestrian segment, such as 50 meters, or an estimated travel time to walk the virtual pedestrian segment. Other attribute information of the virtual pedestrian segment that may be collected include: wheel chair accessible, children friendly, pet friendly, well-lighted area, poorly lighted area, busy area, non-busy area, noisy, peaceful, smelly/polluted, sheltered from rain, not sheltered from rain, no bikes allowed, tree lined, paved area, unpaved area, grassy area, gravel area, dirt area, muddy when wet area, hilly, steps, rough terrain, grade, and any other attribute information. Additionally, the researcher may collect information relating to points of interest proximate the virtual pedestrian segment including location of bike racks, water fountains, toilets, historic sites, recreational facilities, entrances to points of interest or any other information. Additionally, the researcher may collect position data along the virtual pedestrian segment to be used as shape points for cartographically representing the virtual pedestrian segment. In one embodiment, the researcher may capture an image of the virtual pedestrian segment including the surrounding area with a digital camera. Furthermore, the researcher may collect guidance information as discussed below in conjunction with  FIG. 8  for the virtual pedestrian segment.  
      Referring to  FIG. 5 , the researcher continues to identify orientation nodes and virtual pedestrian segments for the unorganized area  522 . For example, another orientation node  534  is identified near tennis courts  536 , and another virtual pedestrian segment  538  connects orientation node  528  with orientation node  534 . Yet another orientation node  540  is identified near the cafe  504  and a parking lot  542 , and another virtual pedestrian segment  544  connects orientation node  534  with orientation node  540 .  
      In alternative embodiments, the steps for collecting pedestrian data for unorganized geographic areas are performed in a different order than presented in  FIG. 6 . In another embodiment, the researcher identifies a first orientation node, identifies a virtual pedestrian segment from the first orientation node and then identifies a second orientation node completing the virtual pedestrian segment. In yet another embodiment, the researcher identifies virtual pedestrian segments and then identifies orientation nodes along the virtual pedestrian segments. For example, the researcher collects pedestrian data for a scenic walk along a lakefront by first identifying virtual pedestrian segments along the lakefront and then identifying orientation nodes between the virtual pedestrian segments.  
       FIG. 7A  illustrates another unorganized geographic area  700 . The unorganized area  700  is a plaza in a city center. A portion of the road network  702  comprising several road segments  704  and nodes  706  surrounds the plaza  700 . The plaza may be paved but lacks underlying organization into paths, such as paths provided by paint markings or paths marked by contrasting paving bricks. Despite the lack of organization into paths, the pedestrian is free to walk through the plaza. In one embodiment, the researcher collects pedestrian data for the plaza  700  in a similar manner as described above in conjunction with  FIG. 6 . For the exemplary embodiment of  FIG. 7A , the researcher identifies the unorganized geographic area  700  of the plaza as appropriate for a virtual pedestrian network because pedestrians may readily traverse the plaza  700  and pedestrians may reduce their travel distance and/or travel time by traversing the plaza  700 .  
      To collect the pedestrian data, the researcher identifies orientation nodes  708  in close proximity to the road network nodes  706  associated with intersecting road segments  702  that bound the plaza  700 .  FIG. 7B  illustrates orientation nodes  708  in close proximity to the road nodes  706  of the intersections bounding the plaza  700 . The researcher also collects attribute information for each of the orientation nodes  708 . The attribute information includes words characterizing the location of the orientation node and any surrounding features, such as the street names of the corresponding intersection, a street address, description of prominent building, prominent signage or point of interest adjacent the orientation node. Additionally, the collected attribute information may include a latitude and longitude position. Other information of the orientation node may be collected including wheel chair accessible, children friendly, pet friendly, well-lighted area, poorly lighted area, busy area, non-busy area, noisy, peaceful, smelly/polluted, sheltered from rain, not sheltered from rain, no bikes allowed, tree lined, paved area, unpaved area, grassy area, gravel area, dirt area, muddy when wet area, shaded, shopping zone, curb cutouts, crosswalks and any other attribute information. In one embodiment, the researcher may capture an image of the orientation nodes including their respective surrounding areas with a digital camera.  
      For the exemplary embodiment of  FIGS. 7A and 7B , the researcher also identifies orientation nodes within the center of plaza  700 . The researcher identifies orientation nodes  710  at the center portions of the plaza  700 . The researcher also collects attribute information for each of the orientation nodes  710 . The attribute information includes words characterizing the location of the orientation node and any surrounding features, such as band pavilion, large fountain, statue of bald man, prominent buildings or any other feature. Additionally, the collected attribute information may include a latitude and longitude position and other information as discussed above for orientation nodes  708 .  
      For the exemplary embodiment of  FIGS. 7A and 7B , the researcher also identifies virtual pedestrian segments  712  between the identified orientation nodes  708  and  710  within the plaza  700 . The researcher identifies the virtual pedestrian segments connecting two of the orientation nodes  708  and  710 . A virtual pedestrian segment may be established between each of the orientation nodes; however, the researcher may decide to establish virtual pedestrian segments between only certain orientation nodes because the path between some of the orientation nodes may be blocked, such as by seasonal cafe seating. The researcher also collects attribute information for each of the virtual pedestrian segments  712 . The attribute information includes descriptive words characterizing the virtual pedestrian segment and any surrounding features. Additionally, the collected attribute information may include an approximate length of the virtual pedestrian segment, or any other attribute information as discussed above. In one embodiment, the researcher may capture an image of the virtual pedestrian segments including their surrounding areas with a digital camera. Referring to  FIG. 7B , after the researcher has identified orientation nodes  708  and  710  and the virtual pedestrian segments  712 , the virtual pedestrian network provides navigatable geometry over which the pedestrian may be routed and guided.  
      B. Collecting Pedestrian Data for Organized Geographic Areas  
      An organized geographic area is a geographic area that has underlying organization into paths and roads. For example, the park illustrated in  FIG. 5 , includes established paths  518  and  520 , paved or unpaved. The geographic researcher collects pedestrian data to provide a pedestrian network using the underlying organization. The pedestrian network is similar to the road network  208 . Whereas the road network  208  comprises road segments and nodes, the pedestrian network comprises pedestrian segments following existing paths and orientation nodes on or near existing paths. Whereas a vehicle may be routed and guided from an origin to a destination over the road network  208 , a pedestrian may be routed and guided from an origin to a destination over, in part or entirely, the pedestrian network which traverses the organized geographic area using existing or established paths. To develop the pedestrian network, the geographic researcher identifies a series of interconnected pedestrian segments and associated orientation nodes. Each pedestrian segment is associated with two orientation nodes; one orientation node represents one end of the pedestrian segment and the other orientation node represents the other end of the pedestrian segment. The orientation node at either end of the pedestrian segment may correspond to a location at which the pedestrian segment meets another pedestrian segment, where the pedestrian segment meets a road segment, where the pedestrian segment meets a virtual pedestrian segment, at a point of interest or where the pedestrian segment dead-ends.  
       FIG. 8  is a flow chart for collecting pedestrian data for organized geographic areas, according to an exemplary embodiment. The steps of  FIG. 8  will be illustrated using the established paths  518  and  520  of the park  214  of  FIG. 5 . In one embodiment, the geographic researcher walks the paths  518  and  520  to collect the pedestrian data. At step  800 , the geographic researcher identifies an orientation node for the existing path  518 . The location of an orientation node is selected at a location that may be readily described to provide orientation to the pedestrian. In one embodiment, orientation nodes are provided at the intersection of two or more established paths. In one embodiment, the orientation node is selected at a location that may be visually identified by the pedestrian. For the exemplary embodiment illustrated in  FIG. 5 , an orientation node  548  is located near the entrance gate  550  of the park. The entrance gate  550  is a prominent feature readily visually observed by the pedestrian. Additionally, a clear and concise description of the entrance gate  550 , such as entrance gate to park from X Street, provides orientation to the pedestrian.  
      At step  802 , the researcher collects attribute information of the orientation node. The attribute information also may include a latitude and longitude position of the orientation node. A positioning system may be used to determine the latitude and longitude position of the orientation node. The position system may utilize GPS-type technology, a dead reckoning-type system, or combinations of these or other systems, all of which are known in the art. The positioning system may include suitable sensing devices to obtain a GPS signal and to measure the traveling distance speed, direction, and so on, of the system. Alternatively, aerial images of the area may be used to determine the position of the orientation node. Other attribute information of the orientation node that may be collected include: wheel chair accessible, children friendly, pet friendly, well-lighted area, poorly lighted area, busy area, non-busy area, noisy, peaceful, smelly/polluted, sheltered from rain, not sheltered from rain, no bikes allowed, tree lined, paved area, unpaved area, grassy area, gravel area, dirt area, muddy when wet area, and any other attribute information. The geographic researcher may record the attribute information using any data collection method, such as handwriting, voice recording, and data entry into a user device.  
      At step  804 , the researcher collects guidance information for the orientation node. Guidance information includes descriptive words characterizing the location of the orientation node and any surrounding features, such as entrance gate to park from X Street for orientation node  548 . These descriptive words will be used as the name for the orientation node. In one embodiment, the researcher collects the name of the orientation node as a name of a feature visible from the location of orientation node. For the example provided in  FIG. 5 , the name for the orientation node may be “entrance gate to park from X Street.” In one embodiment, the researcher identifies the time of day or seasonal restrictions on the descriptive words or orientation node name. For example, during nighttime hours or during the frozen winter, the entrance gate may not be readily visible to the pedestrian. The geographic researcher may record time and season appropriate alternatives.  
      Additional guidance information collected by the researcher is a calculate angle data. That is, the researcher indicates whether maneuvers may be performed at the orientation node, such as at the intersection of two or more pedestrian segments. If maneuvers may be performed at the orientation node, the route guidance feature will have to calculate a maneuver angle. For orientation node  548  in  FIG. 5 , the researcher indicates a yes for the calculate angle data. Furthermore, the researcher collects at explication data. That is, an indication of whether the descriptive words characterizing the location of the orientation node and any surrounding features are helpful to indicate where a maneuver is to be performed or helpful to indicate where the pedestrian is located at when guiding the pedestrian on a route that passes through the orientation node. For the example in  FIG. 5 , the researcher records a yes indication for the at explication data indicating that “at the entrance gate” provides useful guidance for pedestrians at the orientation node  548 . In one embodiment, the researcher may capture an image of the orientation node  548  and its surroundings with a digital camera.  
      In one embodiment, the researcher also collects connection information indicating whether the orientation node is in close proximity to the road network  208 . If the orientation node is close to the road network  208 , the researcher identifies the road node close to the orientation node. In another embodiment, the researcher may identify a road segment for connection information. The researcher may record the connection information in the form of a street address, name or ID of a road segment or road node, a distance from a node along an identified road segment, intersection of two identified road segments, a point of interest or in any other appropriate form. If the orientation node is not close to the road network, the researcher records such an indication.  
      At step  806 , the researcher identifies a pedestrian segment. Referring to  FIG. 5 , the pedestrian segment  552  is a portion of the established path  518 . At step  808 , the researcher collects attribute information of the pedestrian segment  552 . The attribute information also may include a latitude and longitude positions of shape points along the pedestrian segment  552 . The attribute information may also include a distance or length of the pedestrian segment, such as 50 meters or an estimated travel time to walk the pedestrian segment. Other attribute information of the pedestrian segment that may be collected include: wheel chair accessible, children friendly, pet friendly, well-lighted area, poorly lighted area, busy area, non-busy area, noisy, peaceful, smelly/polluted, sheltered from rain, not sheltered from rain, no bikes allowed, tree lined, paved area, unpaved area, grassy area, gravel area, dirt area, muddy when wet area, hilly, steps, rough terrain, grade, and any other attribute information. Additionally, the researcher may collect information relating to points of interest proximate the pedestrian segment including location of bike racks, water fountains, toilets, historic sites, recreational facilities, entrances to points of interest or any other information. Additionally, the researcher may collect position data along the pedestrian segment to be used as shape points for cartographically representing the pedestrian segment. In one embodiment, the researcher may capture an image of the pedestrian segment  552  and its surroundings with a digital camera.  
      At step  810 , the researcher collects guidance information for the pedestrian segment  552 . The guidance information includes descriptive words characterizing the pedestrian segment and any surrounding features. These descriptive words will be used as the name of the pedestrian segment, In one embodiment, the researcher collects the name of the pedestrian segment as a name of a feature visible from the path. In one embodiment, the visible feature is a readily indentifiable geographic feature other than the path itself. In one embodiment, the researcher uses a list of predetermined phase words for the text description the pedestrian segment. Table I lists phrase words that the researcher may use to collect descriptive words characterizing the pedestrian segment according to an exemplary embodiment. Additional phrase words may be used than those listed in Table I.  
                           TABLE I                                   PHRASE ID   PHRASE WORDS                                                    1   ABOVE           2   THROUGH           3   BY           4   KEEPING &lt;blank&gt; ON YOUR               RIGHT           5   BETWEEN           6   UP           7   DOWN           8   ACROSS           9   AFTER           10   ALONG           11   KEEPING &lt;blank&gt; ON YOUR LEFT           12   PAST                      
 
 Referring to  FIG. 5 , the researcher collects descriptive words characterizing the pedestrian segment  552  and/or its surroundings as “keeping the &lt;POND&gt; on your left.” That is, the name of a visible feature from the pedestrian segment  552  is the “POND,” and the phrase words “keeping the &lt;blank&gt; on your left” in conjunction with the visible features provide a text description of the pedestrian segment  552 . In another embodiment, the researcher may collect a more detailed text description of the pedestrian segment without reference to one of the phrase words, such as “walk 20 meters and cross the bicycle path.” In one embodiment, the researcher identifies the time of day or seasonal restrictions on the descriptive words or segment name. For example, during nighttime hours or during the frozen winter, the pond may not be readily visible to the pedestrian. The geographic researcher may record time and season appropriate alternatives. 
 
      The researcher may also record after me data as guidance information. That is, whether describing the pedestrian segment  552  prior to describing the next pedestrian segment  558  is helpful for orientating the pedestrian on a route that passes from the pedestrian segment onto the next pedestrian segment. For the example in  FIG. 5 , the researcher records a no indication for the after me data indicating that “keeping the &lt;POND&gt; on your left” does not provide helpful orientation because the segment name of pedestrian segment  552  is the same as the next pedestrian segment  558  whose segment name is also “keeping the &lt;POND&gt; on your left.” An example of a positive indication for the after me data would be “after the pedestrian bridge.” 
      Additionally, the researcher collects guidance information of do not explicate node data. In one embodiment, one of the endpoints or orientation nodes associated with the pedestrian segment is designated a reference node while the other endpoint or orientation node is designated a non-reference node. In one embodiment, the reference node is the orientation node whose position is the most south and west. For the do not explicate reference node data, the researcher indicates whether the orientation node name of the reference orientation node is not helpful when guiding the pedestrian on a route that passes through the pedestrian segment. For pedestrian segment  552  of  FIG. 5 , the researcher records a no indicating that explicating the name of orientation node  548  “entrance gate” is useful. The researcher also collects guidance information of do not explicate non-reference node data. For the do not explicate non-reference node data, the researcher indicates whether the orientation node name of the non-reference orientation node is not helpful when guiding the pedestrian on a route that passes through the pedestrian segment. For pedestrian segment  552  of  FIG. 5 , the researcher records a no indicating that explicating the name of orientation node  554  “drinking fountain” is useful.  
      In one embodiment, the researcher obtains data representative of the geometry of the pedestrian segment. The geometry of the pedestrian segment may be obtained from aerial or satellite images; alternatively, the researcher may collect latitude and longitude positions at several locations along the pedestrian segment using the positioning system. In one embodiment, the geometry of the pedestrian segment is used to calculate guidance information of angle in and angle out data. The angle in data indicates an initial general direction of the pedestrian segment at the reference orientation node  548 ; angle out data indicates an ending, general direction of the pedestrian segment at the non-reference orientation node  554 . In another embodiment, the researcher may record the angle in and angle out information as he or she traverses the pedestrian segment. For the pedestrian segment  552 , the researcher records the angle in as approximately due east and the angle out as approximately due east.  
      The researcher also determines whether the above recorded guidance information is direction sensitive. For example, the guidance information for pedestrian segment  552  in  FIG. 5  is direction sensitive. If traveling in one direction along the pedestrian segment  552 , the pedestrian segment name should be “keeping the &lt;POND&gt; on your left,” traveling in the opposite direction along the pedestrian segment, the pedestrian segment name should be “keeping the &lt;POND&gt; on your right.” In one embodiment, if the pedestrian segment is direction sensitive, the researcher collects separate guidance data described above for a pedestrian walking in the opposite direction. In one embodiment, the researcher also captures an image of the pedestrian segment  552  and its surroundings with a digital camera. Moreover, in another embodiment, the researcher may identify the location of points of interest, such as toilets, bike racks, drinking fountains, recreation facilities, historical sites or any other point of interest, proximate the pedestrian segment.  
      Referring to  FIG. 8 , the researcher identifies another orientation node along the established path  518  at step  812 . The location of the orientation node is selected at another location that may be readily described to provide orientation to the pedestrian along the established path  518 . The second orientation node is selected at a distance from the first orientation node along the established path  518  such that a pedestrian may be directed from the first orientation node location to the second orientation node location. In one embodiment, the second orientation node selected a distance along the path  518  from the first orientation node such that the pedestrian may visually identify the location of the second orientation node from the location of the first orientation node. In another embodiment, the second orientation node location may be obscured from view or beyond visual identification from the first orientation node location. For example, the pedestrian may be directed to walk along the established path  518  in a certain direction, such as toward a lake, and after walking some distance, the second orientation node comes into view.  
      For the exemplary embodiment illustrated in  FIG. 5 , a second orientation node  554  along the established path  518  is located near a drinking fountain  556 . The drinking fountain  530  is a feature just off of the established path  518  that is readily visually observed by the pedestrian. The second orientation  554  terminates the pedestrian segment  552 .  
      At step  814 , the researcher collects attribute information of the orientation node. The attribute information also may include a latitude and longitude position of the orientation node. The other attribute information for the second orientation node is the same as that described above for the first orientation node. At step  816 , the researcher collects guidance information for the second orientation node  554 . Guidance information for the second orientation node is similar as that described above for the first orientation node  548 . For the orientation node  554 , the collected guidance information includes orientation node name of “the drinking fountain,” no for calculate angle data, and yes for at explication data.  
      Referring to  FIG. 5 , the researcher continues to identify and collect information for orientation nodes and pedestrian segments for the established paths  518  and  520  following the steps of  FIG. 8 . The following description will highlight a portion of the information collected for the exemplary embodiment using  FIG. 5 . The researcher identifies pedestrian segment  558  and collects data attributes and guidance information for the pedestrian segment  558 . Briefly, the collected guidance information for pedestrian segment  558  includes descriptive text characterizing the pedestrian segment  558  as “keeping the &lt;POND&gt; on your left,” a no for after me data, a no for do not explicate reference node data, a no for do not explicate non-reference node data, approximately due east for angle in data, approximately due north for angle out data, and an indication that the above recorded guidance information is direction sensitive for pedestrian segment  558 .  
      The researcher identifies orientation node  562  and collects data attributes and guidance information for the orientation node  562 . For the orientation node  562 , the collected guidance information includes orientation node name of “the pedestrian bridge,” no for calculate angle data, and no for at explication data. The researcher identifies pedestrian segment  564  and collects data attributes and guidance information for the pedestrian segment  564 . Briefly, the collected guidance information for pedestrian segment  564  includes descriptive text characterizing the pedestrian segment  564  as the phrase “across” and “the bridge,” a yes for after me data, a no for do not explicate reference node data, a yes for do not non-reference node data, approximately due north for angle in data, approximately due north for angle out data, and an indication that the above recorded guidance information is not direction sensitive for pedestrian segment  564 .  
      The researcher identifies orientation node  566  and collects data attributes and guidance information for the orientation node  566 . For the orientation node  566 , the collected guidance information includes orientation node name of “the pedestrian bridge,” no for calculate angle data, and no for at explication data. The researcher identifies pedestrian segment  568  and collects data attributes and guidance information for the pedestrian segment  568 . Briefly, the collected guidance information for pedestrian segment  568  includes descriptive text characterizing the pedestrian segment  568  as the phrase “up” and “the hill,” a no for after me data, a no for do not explicate reference node data, a no for do not explicate non-reference node data, approximately due north for angle in data, approximately northeast for angle out data, and an indication that the above recorded guidance information is direction sensitive for pedestrian segment  568 .  
      The researcher identifies orientation node  570  and collects data attributes and guidance information for the orientation node  570 . For the orientation node  570 , the collected guidance information includes orientation node name of “the toilets,” no for calculate angle data, and yes for at explication data. The researcher identifies pedestrian segment  574  and collects data attributes and guidance information for the pedestrian segment  574 . Briefly, the collected guidance information for pedestrian segment  574  includes descriptive text characterizing the pedestrian segment  558  as “keeping the &lt;parking lot&gt; on your left,” a no for after me data, a no for do not explicate reference node data, a no for do not explicate non-reference node data, approximately northeast for angle in data, approximately due east for angles out data, and an indication that the above recorded guidance information is direction sensitive for pedestrian segment  574 . For the orientation node  576 , the collected guidance information includes orientation node name of “the entrance gate for Y Street,” yes for calculate angle data, yes for at explication data, and connection to road segment  512 .  
      In alternative embodiments, the steps for collecting pedestrian data for organized geographic areas may be performed in a different order than presented in  FIG. 8 . In one embodiment, the researcher travels the identified pedestrian segments in both directions to collect different guidance information for each direction of travel. To support multiple languages, the descriptive texts for the orientation nodes, pedestrian segments and other guidance information may be collected in multiple languages according to rules of the individual languages. Alternatively, the guidance texts and other guidance information may be translated to other languages. Additionally, although the collection of guidance information has been described in conjunction with the collection of pedestrian data for organized geographic areas, similar guidance information may be collected for the virtual pedestrian network for unorganized geographic areas including descriptive texts for virtual pedestrian nodes and orientation nodes.  
      Additionally, although the above description for collecting pedestrian data for organized geographic areas has been illustrated using established paths  518  and  520  of the park  214 , the researcher may also collect pedestrian data for the existing road network and for inside buildings as will be briefly described in the following paragraphs.  
      The geographic researcher may collect pedestrian data for the existing road network in a similar manner as described above in conjunction with  FIG. 8 . In one embodiment, the geographic researcher walks the sidewalks along road segments to identify orientation nodes and pedestrian segments and to collect data attributes and guidance information for those orientation nodes and pedestrian segments. The existing sidewalks are like the existing paths  518  and  520  of the park  214 . In one embodiment, the researcher identifies orientation nodes at the intersection of at least two road segments corresponding to a road network node. The identified orientation node may be assigned the same position information as the corresponding road network node. Alternatively, the position information for the orientation nodes may be determined using a positioning system as discussed above. The researcher may also identify additional orientation nodes not associated with the road network nodes. The researcher collects attribute information of the orientation node similar to that described above in conjunction with  FIG. 8 . The researcher also collects guidance information for the orientation node including descriptive texts characterizing the location of the orientation node and identifying a visible feature from the orientation node, calculate angle data, and at explication data. In one embodiment, the researcher also captures an image of the orientation node  548  and its surroundings with a digital camera.  
      In one embodiment, the researcher identifies pedestrian segments along the existing sidewalks. The researcher collects attribute data and guidance information for the pedestrian segment similar to that described above in conjunction with  FIG. 8 . The position information for the pedestrian segment may be identical to the position information for the associated road segment. Alternatively, the position information for the pedestrian segment may be determined using a positioning system as discussed above. The researcher also collects descriptive texts, using phrases from Table I and identifying features visible from the pedestrian segment. The researcher may also record after me data, do not explicate reference node data, do not explicate non-reference node data, angle in and angle out data, and an indication of whether the guidance information is direction sensitive. In one embodiment, the researcher also captures an image of the pedestrian segment and its surroundings with a digital camera. Moreover, in another embodiment, the researcher may identify the location of points of interest proximate the pedestrian segment. The researcher may also collect attribute information of the pedestrian segment including: wheel chair accessible, children friendly, pet friendly, well-lighted area, poorly lighted area, busy area, non-busy area, noisy, peaceful, smelly/polluted, sheltered from rain, not sheltered from rain, no bikes allowed, tree lined, paved area, unpaved area, gravel area, dirt area, hilly, steps, rough terrain, grade, alley, curb cutouts, pedestrian function class similar to road function class, shopping zone, neighborhood zone, traffic light locations, stop sign locations, crosswalks, entrance locations for points of interest, whether associated road segment is crossable at any location, and any other attribute information.  
      Furthermore, the geographic researcher may collect pedestrian data for existing paths inside buildings in a similar manner as described above in conjunction with  FIG. 8 . In one embodiment, the geographic researcher walks the paths, such as hallways, corridors, walkways, stairs, elevators, escalators, in an office building to identify orientation nodes and pedestrian segments and to collect data attributes and guidance information for those orientation nodes and pedestrian segments. In another embodiment, the geographic researcher uses floor plans and building blueprints to collect pedestrian data.  
      In one embodiment, the researcher identifies orientation nodes at the intersection of at least two paths, such as hallways, corridors, walkways, stairs, elevators, escalators or any other path. The researcher may also identify additional orientation nodes at locations that may be readily visually identified based on text descriptions, such as “the water fountain.” Briefly, the researcher collects attribute information of the orientation node similar to that described above in conjunction with  FIG. 8 . The researcher also collects guidance information for the orientation node including descriptive texts characterizing the location of the orientation node and identifying features visible from the orientation node, such as “the copy machine.” The researcher also collects the guidance information of the calculate angle data, and at explication data. In one embodiment, the researcher also captures an image of the orientation node  548  and its surroundings with a digital camera.  
      In one embodiment, the researcher identifies pedestrian segments along the existing paths between established orientation nodes inside the office building. Briefly, the researcher collects attribute information of the pedestrian segment similar to that described above in conjunction with  FIG. 8 . The researcher also collects guidance information for the pedestrian segment including descriptive texts, using phrases from Table I and identifying features visible from the pedestrian segment, such as “keeping the &lt;WATER COOLER&gt; on your right.” The researcher may also record after me data, do not explicate reference node data, do not explicate non-reference node data, angle in and angle out data, and an indication of whether the guidance information is direction sensitive. In one embodiment, the researcher also captures an image of the pedestrian segment and its surroundings with a digital camera. Moreover, in another embodiment, the researcher may identify the location of offices, cubicles, conference rooms, computer equipment, emergency escape routes, number of stairs or any other office item, proximate the pedestrian segment. In other embodiments, the researcher may collect pedestrian data for other buildings, including warehouses, retail stores, museums, libraries, schools, restaurants, or any other structure.  
      In another embodiment, the geographic researcher may collect pedestrian data for inside buildings where paths do not exist in a similar manner as described above in conjunction with the collecting data for the virtual pedestrian network of  FIG. 6 . In one embodiment, the geographic researcher walks the building to identify orientation nodes and virtual pedestrian segments and to collect data attributes and guidance information for those orientation nodes and virtual pedestrian segments.  
      In alternative embodiments, the geographic researcher may collect data similar to the pedestrian data described above in conjunction with  FIG. 8  for the road network. That is, the researcher may collect similar guidance information for road segment and road network nodes.  
      C. Collecting Textual Pedestrian Guidance Data  
      In another embodiment, the researcher collects data to provide a textual guidance route from an identified origin point to an identified destination point. That is, the textual guidance route is a series of messages describing paths and maneuvers to travel from the origin to the destination. In some circumstances, it may be optimal to provide pedestrians with pre-composed textual guidance routes for travel within a certain geographic area, such as a subway station or a large building. For example, a pedestrian exiting a subway car faces a number of somewhat confusing choices for directions to travel and/or exits to connect with the road network and/or pedestrian network.  
       FIG. 9   a  is a flow chart for a collecting textual guidance route, according to an exemplary embodiment. The steps of  FIG. 9   a  will be illustrated with an illustration of a train station  910  in  FIG. 9   b . At step  900 , the researcher identifies an origin and a destination. For the exemplary embodiment, the origin  912  is a train platform where passengers exit a train, and the destination is a southern exit  914  that connects to the road network  916 . At step  902 , the researcher determines a route between the identified origin and destination. In one embodiment, the researcher travels several different routes between the origin and destination and determines which of the available routes is most desirable. When determining which route is most favorable, the researcher may consider several factors including, ease of travel, ease of description, distance traveled, time to traverse route, congestion levels or any other information. At step  904 , the researcher records information for composing a textual guidance route. In one embodiment, the researcher records information in a manner similar to providing verbal instructions for traveling the route from the origin to the destination to another person. The researcher records information explaining how to traverse the route; the information may include orientation information, such as references to surrounding structures, features, points of interest and/or signage, and maneuver information, such as travel up the elevator or stairs, turn left or right, head straight for twenty meters.  
      In one embodiment, the researcher collects time of day related information for the textual guidance route. Using the time of day information, the route determined in step  902  may be modified based on time of the day. For example, the train station may have reversible escalators. In the morning, the escalators may favor train passengers leaving the train station, while in the evening the escalators may favor train passengers arriving at the train station.  
      The following is an example of the textual guidance route information collected by the researcher to travel from the origin of the train platform  912  to the destination of a Y Street exit  914  for the train station  910 : 
          “After exiting the train, turn left. After entering the station, turn right and walk down the stairs. After reaching the bottom of the stairs, veer to the left and head towards the escalators. Take one of the three escalators to the top. After exiting the escalator, walk past the store on your right to another set of escalators. Take one of the two escalators to the top and go through the doors onto Y Street.”       

      At step  906 , the researcher collects attribute information for the textual guidance route. Attribute information may include: wheel chair accessible, children friendly, pet friendly, well-lighted area, poorly lighted area, busy area, non-busy area, noisy, peaceful, smelly/polluted, sheltered from rain, not sheltered from rain, no bikes allowed, stair count, shopping zone, and any other attribute information. In one embodiment, the researcher may identify several textual guidance routes for the same origin to destination. Each route may have specific attributes, such as wheel chair accessible or sheltered from the weather.  
      At step  908 , the researcher identifies any road segments, road nodes, pedestrian segments, virtual pedestrian segments and/or orientation nodes that correspond with the textual guidance route. In the exemplary embodiment, the textual guidance route traverses several pedestrian segments and orientation nodes  918 ,  920 ,  922 ,  924  and  926 .  
      In one embodiment, the textual guidance route may be used to provide transitions between the road network and a public transportation network. In an alternative embodiment, textual guidance routes may be created to guide users for travel over the public transportation network. For example, the researcher may determine a route between an origin and a destination that includes public transportation. An example of the textual guidance route including public transportation recorded by the researcher is, in part, “Take bus  7  at platform  2 . Remain on the bus passing Q Street, L Street and K Street stops. Exit the bus at Y Street stop.” Additionally, the researcher identifies the road segments, road nodes and other geographic features traversed by the public transportation.  
      IV. Geographic Database With Pedestrian Data  
      The pedestrian data collected as described above is included in the geographic database  116  that represents some of the physical geographic features in the geographic region  202 . In the embodiment of  FIG. 3 , the geographic database  116  that represents the geographic region  202  contains at least one pedestrian segment database record  308  for each pedestrian segment identified in the geographic region  202 . The geographic database  116  also includes a pedestrian orientation node database record  310  for each orientation node identified in the geographic region  202 .  
       FIG. 10  shows some of the components of a pedestrian segment data record  308  contained in the geographic database  116 . The pedestrian segment data record  308  includes a segment ID  308 ( 1 ) by which the data record can be identified in the geographic database  116 . Each pedestrian segment data record  308  has associated with it information (such as “attributes”, “fields”, etc.) that describes features of the represented pedestrian segment. The pedestrian segment data record  308  may include data  308 ( 2 ) that indicate a type of pedestrian segment, such as virtual pedestrian path, paved pedestrian path, unpaved pedestrian path, sidewalk, alley, indoor path. The pedestrian segment data record  308  includes data  308 ( 3 ) that indicate a phrase ID and data indicating a name  308 ( 4 ), such as a name of a visible feature from the segment, which together provide a text description characterizing the pedestrian segment. The data indicating the phrase ID provides a predetermined phrase that accompanies the name to describe the pedestrian segment, for example: “keeping the &lt;&gt; on your left” is the phrase and “POND” is the name. The phrase ID may be similar to those illustrated above in Table I.  
      The pedestrian segment data record  304  may also include after me data  308 ( 5 ) indicating whether describing the represented pedestrian segment prior to describing the next pedestrian segment is helpful for orientating the pedestrian on a route that passes from the pedestrian segment onto the next pedestrian segment. The pedestrian segment data record  308  may also include angle in and angle out data  308 ( 7 ) indicating a general direction of the pedestrian segment from the reference orientation node (“angle in”) and a general direction of the end of the pedestrian segment toward the non-reference orientation node (“angle out”). The pedestrian segment data record  308  may further include applicable direction data  308 ( 8 ) indicating whether direction of travel on the pedestrian segment affects how the pedestrian segment should be described, and if so, the direction of travel associated with the above data.  
      The pedestrian segment data record  308  also includes data  308 ( 6 ) relating to the end points of the represented pedestrian segment. The endpoint data includes data  308 ( 6 )( 1 ) indicating whether the reference and/or non-reference orientation node should be identified when describing a route that goes through the pedestrian segment. In one embodiment, the endpoint data  308 ( 6 ) also include references  308 ( 6 )( 2 ) to the orientation node data records  310  that represent the orientation nodes corresponding to the end points of the represented pedestrian segment. The pedestrian segment data record  308  may also include or be associated with other data  308 ( 9 ) that refer to various other attributes of the represented pedestrian segment. In one embodiment, the other data references other database records that provide data representing the geometry of the segment. Additionally, the various attributes associated with a pedestrian segment may be included in a single pedestrian segment record, or may be included in more than one type of record which cross-references to each other. Attributes of the pedestrian segment may be any of the attributed described above in conjunction with the discussion of collecting pedestrian data including: wheel chair accessible, children friendly, pet friendly, well-lighted area, poorly lighted area, busy area, non-busy area, noisy, peaceful, smelly/polluted, sheltered from rain, not sheltered from rain, no bikes allowed, tree lined, paved area, unpaved area, grassy area, gravel area, dirt area, muddy when wet area, shopping zone, neighborhood zone, images and any other attribute information.  
       FIG. 10  also shows some of the components of an orientation node data record  310  contained in the geographic database  116 . Each orientation node data record  310 ( 1 ) and  310 ( 2 ) includes a node ID  310 ( 1 )( 1 ) and  310 ( 2 )( 1 ) by which the data record can be identified in the geographic database  116 . Each of the orientation node data records  310  may have associated information (such as “attributes”, “fields”, etc.) that allows identification of the pedestrian segment(s) that connect to it and/or its geographic position (e.g., its latitude and longitude coordinates). For the embodiment shown in  FIG. 10 , the orientation node data records  310 ( 1 ) and  310 ( 2 ) include the latitude and longitude coordinates 310(1)( 2 ) and  310 ( 2 )( 2 ) for their node.  
      Each orientation node data record also includes data indicating an orientation node name  310 ( 1 )( 3 ) and  310 ( 2 )( 3 ), such as the visible feature name that characterize the location of the orientation node. Each orientation node data record may further include at explication data  310 ( 1 )( 4 ) and  310 ( 2 )( 4 ) indicating whether the orientation node should be referred to when providing guidance for a pedestrian route that passes through the node. Each orientation node data record may further include calculate angle data  310 ( 1 )( 5 ) and  310 ( 2 )( 5 ) indicating whether an angle for a maneuver should be calculated at the orientation node when providing guidance for a pedestrian route that passes through the node. Each orientation node data record also includes connection data  310 ( 1 )( 6 ) and  310 ( 2 )( 6 ) indicating connection, if any, to the road network. In one embodiment, the connection data  310 ( 1 )( 6 ) and  310 ( 2 )( 6 ) are references to the road segment data records  304  and/or road network node data records  306  that represent the road segments and nodes that connect with the orientation node. The node data records  310 ( 1 ) and  310 ( 2 ) may also include other data  310 ( 1 )( 7 ) and  310 ( 2 )( 7 ) that refer to various other attributes of the nodes. Attributes of the orientation node include: wheel chair accessible, children friendly, pet friendly, well-lighted area, poorly lighted area, busy area, non-busy area, noisy, peaceful, smelly/polluted, sheltered from rain, not sheltered from rain, no bikes allowed, tree lined, paved area, unpaved area, grassy area, gravel area, dirt area, muddy when wet area, images and any other attribute information.  
       FIG. 11  is a table  1100  of pedestrian segment data records  308 , according to an exemplary embodiment. The table  1100  represents a portion of the data stored in the geographic database  116 . The columns of the table  1100  correspond with the data described above for the pedestrian segment data record  308  stored in the geographic database  116 . Data in a segment type column  1102  identifies a particular segment type code. For example, segment type code  996  may represent that the pedestrian segment is a paved pedestrian-only path. Data in a segment ID column  1104  provides an identification code by which the data record can be identified in the geographic database  116 . The segment identification code is a unique identifier assigned to a particular pedestrian segment record  308 . For the exemplary embodiment illustrated in  FIG. 11 , the unique segment IDs  1104  are letters; however, other unique identifiers, such as numeric or alphanumeric codes may also be used to uniquely identify a pedestrian segment record  308 .  
      Data in a reference node ID column  1106  and a non-reference node ID column  1108  identify the end points or respective orientation nodes associated with the pedestrian segment with one of the orientation nodes being identified as the reference node and the other being identified as the non-reference node. The data in the reference node ID column  1106  and the non-reference node ID column  1108  provide the orientation node ID of the respective orientation node.  
      Data in a phrase ID column  1110  includes a phrase identification number identifying a particular phrase to use with the segment name to form the text description of the pedestrian segment. Table I provides a list of phrase IDs and associated phrases, according to an exemplary embodiment. Additional phrases and synonyms of the existing phrases may be added to Table I. Data in a name column  1112  provides a name for the pedestrian segment. Data in an after me column  1114  identifies whether or not to begin a pedestrian guidance message for the next pedestrian segment with the word “after” followed by the segment name of the previous pedestrian segment name as found in the segment name column  1112 . For example, the previous pedestrian segment may be pedestrian segment E as depicted in  FIG. 11 . The segment name of pedestrian segment E is “the bridge.” Because the phrase “after the bridge” may be useful to a pedestrian, the after me data for pedestrian segment E may contain a yes, which indicates that a pedestrian guidance message for a pedestrian segment following the bridge may start with “after the bridge.” 
      Data in a do not explicate reference node column  1116  and a do not explicate non-reference node column  1118  may each be used to suppress a reference to the endpoints or orientation nodes associated with the pedestrian segment when providing pedestrian guidance. This feature may be useful when a reference to the orientation node would be meaningless from a particular direction. Data in an angle in column  1120  may identify the angle of travel or direction of travel for an initial portion of the pedestrian segment from the reference orientation node or endpoint. Data in an angle out column  1122  may identify the angle of travel or direction of travel for a final portion of the pedestrian segment toward the non-reference orientation node or endpoint. Data in an applicable in the from reference node direction column  1124  and an applicable in the to reference node direction column  1126  may be used when the pedestrian guidance message may be different depending on a direction of travel (i.e., towards or away from the associate reference orientation node). The table  1100  may include additional data. For example, the table may include a column identifying connection data of an associated road segment ID or road network node ID.  
       FIG. 12  is a table  1200  of orientation node records  310 , according to an exemplary embodiment. The table  1200  represents a portion of the data stored in the geographic database  116 . The columns of the table  1200  correspond with the data described above for the orientation node data records  310  stored in the geographic database  116 . Data in a node ID column  1202  provides an identification code by which the orientation node data record can be identified in the geographic database  116 . The orientation node identification code is a unique identifier assigned to a particular orientation node data record  310 . For the exemplary embodiment illustrated in  FIG. 12 , the unique orientation node ID are numbers; however, other unique identifiers, such as numeric or alphanumeric codes may also be used to uniquely identify an orientation node data record  310 .  
      Data in columns  1204  and  1206  provide the coordinates, latitude and longitude, of each orientation node  310 . Data in a name column  1208  includes a name of the orientation node. Data in a calculate angle column  1210  identifies whether or not at the orientation node a maneuver angle should be determined for providing pedestrian guidance through the node. If a calculate angle data contains a no (N), then no angle needs to be determined. If the calculate angle data contains a yes (Y), then a maneuver angle is determined when providing pedestrian guidance through the node.  
      Data in an at explication column  1212  identifies whether or not the name in the orientation node name data is to be used in a pedestrian guidance message at the orientation node. In some situations, describing the current orientation node in a pedestrian guidance message may be useful to a pedestrian. In that case, at explication data contains a yes so that a reference to the current orientation node is added to the pedestrian guidance message. However, in other situations adding a reference to the current orientation node may be awkward and not provide useful guidance to a pedestrian. For example, when a pedestrian arrives at a bridge, a message “At the bridge, walk across the bridge,” would be awkward. By filling the at explication data with a no, the pedestrian would receive the message, “Walk across the bridge.” Data in a connection column  1214  provides references to the road network data records, either road segment data records  304  or node data records  306 , that connect with the orientation node.  
       FIG. 13  shows some of the components of a pedestrian textual guidance route data record  1300  contained in the geographic database  116 . The pedestrian textual guidance route guidance data record  1300  contains information collected to provide complete textual guidance route from a specified origin to a specified destination. The pedestrian textual guidance route data record  1300  includes a text guidance route ID  1302  by which the data record can be identified in the geographic database  116 . Each pedestrian textual guidance route data record  1300  contains a complete route guidance text from the established origin to the established destination in the route guidance text data  1304 . An example of the route guidance text data  1304  is the following between an origin of a train platform to the destination of a Y Street exit for a train station: 
          “After exiting the train, turn left. After entering the station, turn right and walk down the stairs. After reaching the bottom of the stairs, veer to the left and head toward the escalators. Take one of the three escalators to the top. After exiting the escalator, walk past the store on your right to another set of escalators. Take one of the two escalators to the top and go through the doors onto Y Street.”       
      Each pedestrian textual guidance route data record  1300  has associated with it attribute data  1306  that describes features of the route guidance text such as: wheel chair accessible, well-lighted area, busy area, noisy, sheltered from rain, stair count, shopping zone, images and any other attribute information. In one embodiment, the pedestrian textual guidance route data record  1300  includes alternative route guidance text for different times of the day.  
      The pedestrian text route guidance data record  1300  also includes data  1308  relating to the segments and/or nodes traversed by the route guidance text. The data  1308  provides references to the segments and/or nodes traversed by the route. The data  1308  may be used to provide a map display with a route highlight corresponding to the segments traversed by the route guidance text. The pedestrian text route guidance data record  1300  includes data  1310  relating to the end points of the represented route guidance text. The endpoint data includes data indicating the origin and destination of the represented route guidance text. In one embodiment, the endpoint data  1310  include references to the node data records  306  and  310  and point of interest data records that represent the node(s) and/or point of interest corresponding to the origin and destination of the represented route guidance text. The pedestrian textual guidance route data record  1300  may also include or be associated with other data  1312  that refer to various other information of the represented route guidance text.  
      Referring to  FIG. 4 , the road segment data records  304  and road network node data records  306  may also include pedestrian-related data  304 ( 5 ) and  306 ( 1 )( 2 ),  306 ( 2 )( 2 ). In one embodiment, the pedestrian-related data  304 ( 5 ) associated with the road segment data record  304  are references to pedestrian segment data records  308  associated with the road segment, such as pedestrian segments representing sidewalks. Similarly, the pedestrian-related data  306 ( 1 )( 2 ),  306 ( 2 )( 2 ) associated with the road network node data record  306  are references to orientation node data records  310  associated with the road nodes. In another embodiment, the pedestrian-related data  304 ( 5 ) and  306 ( 1 )( 2 ) are references to pedestrian text route guidance data records  1300  associated with the road segments, road nodes or points of interest proximate the road segments or road nodes.  
      In another embodiment, the pedestrian-related data  304 ( 5 ) associated with the road segment data record  304  are pedestrian-related attributes of the road segment, such as a description of sidewalks, location of crosswalks, crosscut curbs, tree-lined, location of traffic signals, location of stop signs, pedestrian enablement, crossability of road segment, noisy, polluted, bike-friendly, wheel chair accessible, shopping zone, neighborhood zone or any other attribute information. The pedestrian-related data  306 ( 1 )( 2 ) associated with the road node data records  306  are similar pedestrian-related attributes of the road node.  
      V. Route Calculation for a Pedestrian  
      As discussed above in conjunction with  FIG. 1 , the navigation system  100  includes navigation application software programs  110  that provide the various navigation features and functions. In one embodiment, the navigation functions and features may include route calculation  124  for a pedestrian. The route calculation function  124  receives a request to calculate a route to a desired destination. The request may be in the form of an identification of a starting location and a desired destination location. The identification of these locations may include the geographic coordinates of these locations. The route calculation function may also be provided with other data or parameters, such as walking preferences (e.g., avoid polluted areas). Given at least the identification of the starting location and the destination location, the route calculation function  124  attempts to determine one or more solution routes between the starting location and the destination location. A solution route is formed of a series of connected road and/or pedestrian segments over which the pedestrian can travel from the starting location to the destination location. When the route calculation function  124  calculates a route, it accesses the geographic database  116  and obtains road segment data entities  304  and/or pedestrian segment data entities  308  that represent segments around and between the starting location and the destination location. The route calculation function  124  uses the information in the road and/or pedestrian segment data entities  304  and  308  to attempt to determine at least one valid solution route from the starting location to the destination location. In determining a valid solution route for the pedestrian to travel, the route calculation program  124  uses the data attributes associated with the road and/or pedestrian segment data entities to account for walking preferences (e.g., paved surface, tree lined). The route calculation function  124  may attempt to find a solution route that takes the least time to travel, that covers the least distance, or that meets some other specifiable criteria.  
      The route calculation function  124  may use various means or algorithms in determining solution routes. Methods for route calculation are disclosed in U.S. Pat. No. 6,192,314, the entire disclosure of which is incorporated by reference herein. (The methods disclosed in the aforementioned patent represent only some of the ways that routes can be calculated and the claimed subject matter herein is not limited to any particular method of route calculation. Any suitable route calculation method now known or developed in the future may be employed.)  
      The route calculation function  124  provides an output. In one embodiment, the output of the route calculation function  124  is in the form of an ordered list  1400  identifying a plurality of road and/or pedestrian segment data entities.  FIG. 14  illustrates the pedestrian segment data entities  308  (i.e., seg 1 , seg 2 , seg 3 , . . . , seg(E), seg(F)) from the geographic database  116  included in an exemplary output list  1300  generated by the route calculation function  124 . The plurality of pedestrian segment data entities  1400  represent the pedestrian segments that form the continuous navigable route between the origin and the destination that had been calculated by the route calculation function  124 . (The route calculation function  124  may calculate more than one solution route.)  
      VI. Route Guidance for a Pedestrian  
      As discussed above in conjunction with  FIG. 1 , the navigation system  100  includes navigation application software programs  110  that provide the various navigation features and functions. The navigation functions and features may include route guidance  126  for a pedestrian. The route guidance function  126  provides detailed direction for reaching a desired destination. In one embodiment, the list  1400  of pedestrian segment data entities determined by the route calculation function  124  is provided to the route guidance function  126 . The route guidance function  126  uses the information in the list  1400 , as well as additional information from the geographic database  116 , to provide instructions to the end user to travel the route defined by the list  1400  output by the route calculation function  124 . The route guidance function  126  may include functions that identify locations along the calculated route at which maneuvering instructions may be provided to the end user. The route guidance function  126  may provide the maneuvering instructions all at once, or alternatively, the route guidance function  126  may provide the maneuvering instructions one at a time as the pedestrian is traveling. In one embodiment, each maneuvering instruction is provided separately (or in small groups of combined maneuvering instructions) in advance of when the specific maneuver is required to be taken so that the end user can prepare to make the required maneuver. The output of the route guidance function  126  is provided to the end user through a user interface  114  included on the computing platform  102 . The output of the route guidance may be conveyed audibly through speech synthesis or on a visual display.  
      Methods for providing route guidance using geographic data are disclosed in U.S. Pat. No. 6,199,013, the entire disclosure of which is incorporated herein by reference. (The methods disclosed in the aforementioned patent represent only some of the ways that route guidance can be calculated and the claimed subject matter herein is not limited to any particular method of route guidance. Any suitable route guidance method now known or developed in the future may be employed.)  
      In order to provide maneuvering instructions at appropriate times and/or locations, the navigation system  100  uses data from the positioning system ( 112  in  FIG. 1 ). The positioning system  112  determines the position of the pedestrian (computing platform  102 ) as he or she is traveling. A positioning (map-matching) function  130  in the navigation programming  110  compares the pedestrian&#39;s position determined by the positioning system  112  to the positions of the pedestrian segments represented by the pedestrian segment data entities in the solution walking route  1400 . Using this comparison, the maneuver instructions, which are related to positions along the solution walking route, can be provided at appropriates times as these positions are approached.  
      The route guidance function  126  may also provide the end user with information about the remaining distance to the destination location. The list  1400  of pedestrian segment data entities from the route calculation function  124  may also be provided to the map display function  128 . The map display function  128  uses the information in the list  1400 , as well as additional information from the geographic database  116 , to provide graphical maps on a display of the user interface  114 . The graphical maps illustrate the areas through which the calculated route passes. The path of the calculated route may be highlighted on the displayed maps.  
      The route guidance function  126  includes a pedestrian guidance function that generates pedestrian guidance messages having sufficient information to guide the pedestrian along the calculated walking route and to reduce the likelihood of the pedestrian becoming confused as to their orientation. In one embodiment, the pedestrian guidance function generates a pedestrian guidance message for each pedestrian segment in the ordered list  1400  from the route calculation function  124 . In the exemplary embodiment, each pedestrian guidance message provides a reference to a previous pedestrian segment (if any), followed by a reference to a current orientation node, followed by a reference to a current pedestrian segment, which is followed by a reference to a next orientation node. Not all pedestrian guidance messages contain all four references. In one embodiment, data in the orientation node data entities  310  and the pedestrian segment data entities  308  of the geographic database  116  indicate what information to include in the pedestrian guidance message.  
       FIG. 15  is a flow chart that depicts the steps performed by the pedestrian guidance function to generate a pedestrian guidance message, according to an exemplary embodiment. At block  1500 , the pedestrian guidance function determines whether to reference a previous pedestrian segment. At block  1502 , the pedestrian guidance function determines whether to reference a current orientation node. At block  1504 , the pedestrian guidance function determines whether to provide a direction of travel. At block  1506 , the pedestrian guidance function includes a reference to a current pedestrian segment. At block  1508 , the pedestrian guidance function determines whether to reference a next orientation node. At block  1510 , the pedestrian guidance message is created based on the determinations performed at blocks  1500 - 1504 ,  1508 - 1510  and the reference to the current pedestrian segment performed at block  1506 . The steps performed by the pedestrian guidance function for constructing the pedestrian guidance message are described with more detail with reference to  FIGS. 16A-16D .  
       FIGS. 16A-16D  are flow charts that depict a more detailed method of constructing the pedestrian guidance message as specified in  FIG. 15 , according to an exemplary embodiment. At block  1600 , the pedestrian guidance function determines whether the pedestrian guidance message should reference a previous pedestrian segment. Specifically, at block  1602 , the pedestrian guidance function obtains the after me data  308 ( 5 ) in the pedestrian segment data record  308  in the geographic database  116  for the previous pedestrian segment of the ordered list  1400 , if any. The after me data may contain a yes or a no. At block  1604 , if the after me data of the previous pedestrian segment indicates a yes, then the pedestrian guidance function begins the pedestrian guidance message with the word “after.” At block  1606 , if the pedestrian guidance message begins with the word “after,” the pedestrian guidance function retrieves the name of the previous pedestrian segment from the name data  308 ( 4 ) of the previous pedestrian segment data record  308  and adds the name to the pedestrian guidance message. A comma is then added to the pedestrian guidance message for grammatical purposes. Otherwise, at block  1608 , the pedestrian guidance message does not begin with a reference to the previous pedestrian segment.  
      At block  1610 , the pedestrian guidance function determines whether to reference a current orientation node in the pedestrian guidance message. At block  1612 , the pedestrian guidance function obtains the at explication data in the current orientation node data record  310  in the geographic database  116 . The at explication data may contain a yes or a no. At block  1614 , if the at explication data contains a yes, then the pedestrian guidance function begins or continues the pedestrian guidance message with the word “at.” At block  1616 , the pedestrian guidance function obtains name of the current orientation node from the orientation node name data for the current orientation node data record and adds the name to the pedestrian guidance message. A comma is then added to the pedestrian guidance message for grammatical purposes. Otherwise, at block  1618 , the pedestrian guidance message does not include the name of the current orientation node.  
      At block  1620 , the pedestrian guidance function determinates whether to provide a direction of travel. At block  1622 , the pedestrian guidance function checks the calculate angle data in the geographic database  116  for the current orientation node data record. The calculate angle data may be filled with a yes or a no. At block  1624 , if the calculate angle data contains a yes, then the pedestrian guidance function calculates an angle between the previous pedestrian segment and the current pedestrian segment. In one embodiment, the magnitude and the direction of the angle between the two pedestrian segments is determined using the angle out data associated with the previous pedestrian segment and the angle in data associated with the current pedestrian segment. The magnitude and direction of the calculated angle is then used to determine which directional text to add to a pedestrian guidance message. For example, if the magnitude of the angle between the two pedestrian segments is less than ten degrees, then a phrase such as “continue straight” may be added to the pedestrian guidance message. As the magnitude of the angle increases, the direction of the angle may be used to determine whether to direct the pedestrian to turn to the left or to the right. Additionally, a phrase indicative of the magnitude of the turn may be added to the message. For example, the word “slight” may be added to the message for smaller angles and the word “sharp” may be added to the message when the angle between the pedestrian segments is large.  
      After the angle calculation is performed, at block  1626 , the pedestrian guidance function adds text describing the direction of travel to the pedestrian guidance message. The text may be chosen based on the magnitude and the direction of the angle. For example, the text may be: turn sharp left, turn left, turn slight left, continue straight, turn slight right, turn right, and turn sharp right. After the directional text is added to the pedestrian guidance message, at block  1628  the pedestrian guidance function includes the word “and” to the pedestrian guidance message. Otherwise, at block  1630 , the pedestrian guidance message does not include the direction of travel.  
      At block  1632 , the pedestrian guidance function determines how to reference a current pedestrian segment in the pedestrian guidance. At block  1634 , the pedestrian guidance function determines whether the pedestrian segment data record  308  for the current pedestrian segment includes a phrase ID. If a phrase ID exists, at block  1636 , the pedestrian guidance function adds the word “walk” to the pedestrian guidance message. At block  1638 , the pedestrian guidance function identifies the phrase associated with the pedestrian segment and adds the phrase to the pedestrian guidance message. The phrase ID data represent a number associated with a particular phrase, such as the phrase IDs and corresponding phrases depicted in Table I. At block  1640 , the pedestrian guidance function obtains the name of the current pedestrian segment from the name data  308 ( 4 ) and adds the name to the pedestrian guidance message. Otherwise, at block  1642 , the pedestrian guidance message includes only the name of the current pedestrian segment.  
      At block  1644 , the pedestrian guidance function determines whether to reference the next orientation node. At block  1646 , the pedestrian guidance function obtains data from the explicate node data record  308 ( 6 )( 1 ) of the pedestrian segment data record  308 . As illustrated in  FIG. 11 , the do not explicate reference or non-reference node data may be filled with a yes or a no. At block  1648 , if the do not explicate reference or non-reference node data contain a no, then the pedestrian guidance message then includes the word “toward.” At block  1650 , the word “toward” is followed by the name in the orientation node name record  310 ( 2 )( 3 ). Otherwise, the pedestrian guidance message does not include the next orientation node name.  
       FIGS. 17A and 17B  provide two examples of the pedestrian guidance function using information from the geographic database  116  to generate pedestrian guidance messages. In  FIG. 17A , example 1, the pedestrian guidance function obtains the illustrated data for the previous pedestrian segment, the current orientation node, the current pedestrian segment and the next orientation node. For example 1, the pedestrian guidance function obtains a no for the after me data of the previous pedestrian segment; a yes for the at explication data, “the statue” for the node name data, and a yes for the calculate angle data of the current orientation node; a “10” (corresponding to “along”) for the phrase ID data, “the brick path” for the segment name data, and a no for the do not explicate reference node data of the current pedestrian segment; and “the pond” for the node name of the next orientation node.  
      Because the after me data contains a no, the pedestrian guidance message does not begin with the word “after” followed by a previous pedestrian segment name. Because the at explication data contains a yes, the pedestrian guidance message begins with the word “at” followed by the name of the current orientation node. A comma may then be added to the introductory phrase for grammatical purposes. Accordingly, the introductory phrase for the pedestrian guidance message in Example 1 is “At the statue.” 
      Continuing with example 1, maneuver text is added to the introductory phrase because the calculate angle data contains a yes. The pedestrian guidance function calculates the angle between the previous pathway segment and the current pathway segment. The magnitude and direction of the angle determines what maneuver text to add to the pedestrian guidance message. In this example, the angle corresponds with the phrase “turn right” which is added to the message. The word “and” is then added to the message after the maneuver text.  
      Because the phrase ID data is filled with the number  10 , the pedestrian guidance message includes the word “walk” followed by the phrase associated with phrase ID  10 , which is depicted in Table I as the word “along.” The name of the current pedestrian segment “the brick path” is then added to the message.  
      Because the do not explicate reference node data is filled with a no, the message in Example 1 concludes with the word “toward” followed by the name of the next orientation node, “the pond.” As a result, the pedestrian guidance message in example 1 is “At the statue, turn right and walk along the brick path toward the pond.” 
      In  FIG. 17B , example 2, the pedestrian guidance function obtains the illustrated data for the previous pedestrian segment, the current orientation node, current pedestrian segment and next orientation node. For example 2, the pedestrian guidance function obtains a no for the after me data of the previous pedestrian segment; a yes for the at explication data, “the fountain” for the node name data, and a no for the calculate angle data of the current orientation node; a “4” (corresponding to “keeping &lt;blank&gt; on your right”) for the phrase ID data, “the kayaking course” for the segment name data, and a yes for the do not explicate reference node data of the current pedestrian segment; and “the kayaking course” for the node name of the next orientation node.  
      Because the after me data contains a no, the pedestrian guidance message does not begin with the word “after” followed by a previous pedestrian segment name. Because the at explication data contains a yes, the pedestrian guidance message begins with the word “at” followed by the name of the current orientation node. A comma may then be added to the introductory phrase for grammatical purposes. Accordingly, the introductory phrase for the pedestrian guidance message in example 2 is “At the fountain.” 
      Continuing with example 2, no maneuver text is added to the introductory phrase because the calculate angle data contains a no. Because the phrase ID data is filled with the number  4 , the pedestrian guidance message includes the word “walk” followed by the phrase associated with phrase ID  4 , which is depicted in Table I as the phrase “keeping &lt;blank&gt; on your right.” The name of the current pedestrian segment “the kayaking course” is then added to the message. Because the do not explicate reference node data is a yes, the message concludes without referencing the name of the next orientation node. As a result, the pedestrian guidance message in example 2 is “At the fountain, walk keeping the kayaking course on your right.” 
      As depicted in  FIGS. 17A and 17B , the pedestrian guidance messages initially orient the pedestrian by referencing either an orientation node name or a pedestrian segment name that the pedestrian can currently see (e.g., at the statue, at the fountain). This initial orientation may provide reassurance to the pedestrian that they are starting at the correct location. The pedestrian guidance message may then provide guidance as to how to travel from this starting point, including maneuvers as necessary. In alternative embodiments, the pedestrian receives additional guidance as necessary.  
      VII. Example of Route Guidance for a Pedestrian  
       FIGS. 18A, 18B  and  18 C illustrate examples of a pedestrian guidance messages displayed on the user interface  114  of the computing platform  102 . Referring to  FIG. 18A and 18B , the pedestrian is arriving at a train station and wants to walk to the beach. With the user interface  114  of the computing platform  102 , the pedestrian enters his or her desired destination of the beach. In one embodiment, the user device determines the pedestrian&#39;s origin; alternatively, the pedestrian enters his or her origin of the train station. The navigation system  100  performs the route calculation function  124  in the manner described above using the geographic database with the collected pedestrian data to generate a list of connected pedestrian segments from the train station to the beach. The navigation system then performs the route guidance function  126  in the manner described above using the geographic database  116  with the collected pedestrian data to provide the pedestrian guidance messages illustrated in  FIG. 18A .  
      Referring to  FIG. 18A , the user interface  114  displays a first pedestrian guidance message  1800  that provides guidance from the train platform to K Street exit for a train station:  
      “Turn right after exiting the train. After entering the station, turn right and walk down the stairs. After reaching the bottom of the stairs, veer to the left and head towards the escalators. Go through the doors to the right of the escalators onto K Street.” 
      Referring to  FIG. 18B , after the pedestrian has exited the train station, the user interface  114  displays a second pedestrian guidance message  1802  which initially orients the pedestrian by referencing the origin provided by the pedestrian or the user device. The phrase “At the train station” references a readily visible feature, the train station, in close proximity to the pedestrian. The message then describes the second pedestrian segment by directing the pedestrian to “turn right” and walk “along K Street” toward the orientation node referenced with the “traffic signal.” Upon reaching the end of the second pedestrian segment of the calculated route, the user interface  114  displays a pedestrian guidance message  1804 . The message  1804  orientates the pedestrian and provides a maneuver instruction of “turn left.” The message  1804  then describes the third pedestrian segment by directing the pedestrian to walk “along North Avenue” toward the next orientation node referenced with “the cul-de-sac.” Upon reaching the end of the third pedestrian segment of the calculated route, the user interface  114  displays a fourth pedestrian guidance message  1806 . The message  1806  orientates the pedestrian at the orientation node and describes the fourth pedestrian segment by directing the pedestrian to walk “down the stairs” toward the next orientation node referenced with “the tunnel.” Upon reaching the end of the fourth pedestrian segment of the calculated route, the user interface  114  displays a fifth pedestrian guidance message  1808 . The message  1808  orientates the pedestrian and describes the fifth pedestrian segment by directing the pedestrian to walk “through the tunnel.” Upon reaching the end of the fifth pedestrian segment of the calculated route, the user interface  114  displays a pedestrian guidance message  1810 . The message  1810  orientates the pedestrian and provides a maneuver instruction of “turn right.” The message  1810  then describes the sixth pedestrian segment by directing the pedestrian to walk “across the bicycle path” toward the next orientation node referenced with “the beach,” the pedestrian&#39;s desired destination.  
      Referring to  FIG. 18C , the pedestrian is at the beach and wants to walk to the zoo. With the user interface  114  of the computing platform  102 , the pedestrian enters his or her desired destination of the zoo. The navigation system  100  performs the route calculation function  124  in the manner described above using the geographic database with the collected pedestrian data to generate a list of connected pedestrian segments from the beach to the zoo. The navigation system then performs the route guidance function  126  in the manner described above using the geographic database  116  with the collected pedestrian data to provide the pedestrian guidance messages illustrated in  FIG. 18C .  
      Referring to  FIG. 18C , the user interface  114  displays a first pedestrian guidance message  1812  initially orienting the pedestrian by referencing the origin provided by the pedestrian or the user device. The phrase “At the boat house” references a point of interest, namely a readily visible boat house, in close proximity to the origin of the pedestrian. The message then describes the first pedestrian segment by directing the pedestrian to walk “keeping Lake Michigan on your right” toward the orientation node referenced with the “pedestrian bridge.” Upon reaching the end of the first pedestrian segment of the calculated route, the user interface  114  displays a second pedestrian guidance message  1814 . The second message  1814  describes the second pedestrian segment by directing the pedestrian to walk “across the pedestrian bridge.” Upon reaching the end of the second pedestrian segment of the calculated route, the user interface  114  displays a third pedestrian guidance message  1816 . The third message  1816  orientates the pedestrian at the orientation node and describes the third pedestrian segment by directing the pedestrian to walk “keeping the parking lot on your right” toward the next orientation node referenced with “the volleyball court.” Upon reaching the end of the third pedestrian segment of the calculated route, the user interface  114  displays a fourth pedestrian guidance message  1818 . The fourth message  1818  orientates the pedestrian and provides a maneuver instruction of “turn left.” The fourth message then describes the fourth pedestrian segment by directing the pedestrian to walk “up the hill” toward the next orientation node referenced as “the statue of a man on a horse.” Upon reaching the end of the fourth pedestrian segment of the calculated route, the user interface  114  displays a fifth pedestrian guidance message  1820 . The fifth message  1820  orientates the pedestrian and describes the fifth pedestrian segment by directing the pedestrian to walk “toward the zoo entrance next to the flag pole,” the pedestrian&#39;s desired destination.  
       FIGS. 18A, 18B  and  18 C depict pedestrian guidance messages displayed on the user interface  114  of the computing platform  102 ; however, the pedestrian guidance messages may be an audio message in another embodiment. Additionally, the computing platform  102  illustrated in  FIGS. 18A, 18B  and  18 C is a PDA; however, other user devices, such as a cellular telephone, may also be used to provide the pedestrian guidance message to the pedestrian. Further, a person may obtain the pedestrian guidance messages prior to walking. For example, a person may get pedestrian guidance messages from an in-vehicle navigation system or a computer, which may be printed and taken with the person to a walking origin location. As yet another example, the pedestrian may obtain pedestrian guidance from a public-access device, such as an Internet web site, a computer terminal, or a kiosk. Additionally, the text in the message may be converted to a voice message using standard text-to-speech techniques.  
      While the  FIGS. 18A, 18B  and  18 C depict pedestrian guidance messages that a pedestrian may receive from the navigation system  100 , the navigation system  100  may also provide additional pedestrian guidance in the form of maps and images. In one embodiment, the navigation system uses the list  1400  of road and/or pedestrian segments to provide a display of a map with a route highlight corresponding to the route. In another embodiment, the navigation system  100  may also provide images of portions of the route. A more detailed description of providing images may be found in the co-pending application entitled “METHOD OF OPERATING A NAVIGATION SYSTEM USING IMAGES” filed the same date herewith, Attorney Docket No. N0193US, the entire disclosure of which is incorporated by reference herein. In another embodiment, the pedestrian guidance messages may share the screen with images, or the user device may include a push button selection that allows the pedestrian to toggle between the pedestrian guidance message and the map and/or images. As the pedestrian walks, a pedestrian guidance message, map, and/or images may orient the pedestrian and provide confirmation that the pedestrian is traveling in the correct direction. The type of device that the pedestrian is using to request the pedestrian guidance may determine what type of pedestrian guidance the pedestrian receives. For example, if the pedestrian uses a device that cannot support graphics, the pedestrian may only receive a pedestrian guidance message.  
      VIII. Further Embodiments  
      In one embodiment, the pedestrian data discussed above may be used for identifying a user&#39;s current location in the absence of a GPS signal and local knowledge of the area. For example, a user unfamiliar with the area may not know street names and street addresses. The following method may be used for origin selection in place of the current position from the GPS positioning system or entry of address or street information. In one embodiment, the user enters a desired destination. Based on a proximity to the destination, such as a typical walking distance for a pedestrian of 2 kilometers, the navigation system  100  presents the user with a series of questions asking if a specific geographic feature is visible from the user&#39;s current location, such as “Do you see a harbor?” or “Do you see a Ferris wheel?” The navigation system  100  selects visible features for the questions from the name of the pedestrian segments and orientation nodes in the database  116  proximate the selected destination. When the user answers one of the questions affirmatively, the navigation system  100  focuses the questions to features close to the location of the visible feature to identify the precise segment or node at which the user is located.  
      Furthermore, although the above description has been describing the navigation features and functions for a pedestrian, any other mode of transportation may also be used, such as motor vehicle, motorcycle, scooter, inline-skates, bicycle or any other. The claims should not be read as limited to the described order or elements unless stated to that effect. All embodiments that come within the scope and spirit of the following claims and equivalents thereto are claimed as the invention.