Abstract:
A navigation device is disclosed. In at least one embodiment, the navigation device includes a storage device to store map information and points of interest (POIs), the POIs including description information and location information; and a display to display stored POIs at a location of the map information, based upon the location information, POIs being selectively retrievable from a remote location for subsequent storage and display.

Description:
PRIORITY PARAGRAPH 
     The present application is a continuation of U.S. patent application Ser. No. 12/292,102 filed on Nov. 12, 2008, which itself is a continuation of U.S. patent application Ser. No. 11/428,832 filed on Jul. 5, 2006, now abandoned, and which itself is a continuation of U.S. patent application Ser. No. 10/452,492 filed on Jun. 2, 2003, also now abandoned. The entire contents of each of these applications is incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a personal GPS navigation device. A personal GPS navigation device is any electronic device that can process GPS location data and display the location of the device on a map. The device may be a dedicated navigation device, or a general purpose electronic device, such as a personal digital assistant, smart phone, mobile telephone, laptop or palmtop computer. The device may be portable or fixed in a vehicle. 
     2. Description of the Prior Art 
     Personal navigation devices are becoming increasingly common. A particularly successful approach is to connect a PocketPC™ powered PDA (personal digital assistant) to a GPS receiver: the PDA, when running navigation software, becomes a GPS based personal navigation device. Another successful format is the dedicated GPS device, used by hikers, sailors etc. In some countries, mobile telephones will have to be equipped with a GPS receiver in order to be able to send the location of that telephone in the event of an emergency, greatly increasing the adopting of GPS technology as a mass market technology. Portable GPS receiver devices have also been used in personal safety devices as described in, for instance, U.S. Pat. No. 6,480,557 to Rog, et al. entitled “Portable GPS-receiver for a personal safety system”, the contents of which are hereby incorporated by reference. 
     GPS device have also been incorporated into road vehicles and integrated into road map data bases to provide navigation and vehicle tracking systems as described in, for instance, U.S. Pat. No. 4,837,700 to Ando, et al. entitled “Method and apparatus for processing data in a GPS receiving device in a road vehicle” and U.S. Pat. No. 5,225,842 to Brown, et al. entitled “Vehicle tracking system employing global positioning system (GPS) satellites”, the contents of both of which patents are hereby incorporated by reference. 
     One common feature of current personal GPS navigation devices is that they can display a GPS information screen, such as the screen shown in  FIG. 1B . The GPS information screen shows: how many GPS satellite signals are being received and their individual strength at  3   a ; the location co-ordinates of the device at  3   b ; the speed of the device at  3   c ; the direction of movement of the device at  3   d ; the relative orientation of GPS satellites that a signal is being picked up from at  3   e . The GPS information screen is useful when getting a first GPS fix. Once a fix has been established, most users then switch to the map mode, which causes a map to be displayed on the screen of the personal navigation device, indicating the location of the device with an arrow. 
     SUMMARY OF THE PRESENT INVENTION 
     In a first aspect, a personal GPS navigation device is programmed to display, at the same time, each of the following:
         (a) a map;   (b) an indication of the current position of the device on the map; and   (c) a GPS signal strength indicator.       

     Hence, the device differs from the prior art in displaying a GPS signal strength indicator at the same time as the navigation map (e.g. when the device is in navigation mode) and hence does not require a user to leave the navigation mode to call up a separate GPS information screen in order to see the GPS signal strength. This is very useful, particularly for ordinary consumers, who can see at a glance if the reason that location tracking has been lost is because the received GPS signals are inadequate. (The approach is similar to how network coverage is shown on both the idle screen of a cellular mobile telephone and when a voice call is being made: it is very useful to have the strength of the network coverage graphically represented on the screen that is seen when actually about to make/receive or actually making a voice call.) 
     In one implementation, the GPS signal strength indicator comprises several bars, with all bars being visible if the strength of the received GPS signal exceeds a predefined requirement and none visible if the GPS signal strength is below a second predefined requirement. The term ‘bar’ should be expansively construed to cover any region, icon, graphic of any shape that can visually represent a signal strength level. The GPS signal strength indicator can be part of the main display used to display the map or can be discrete, separate hardware entirely, such as LED indicators on the housing of the device. A bar is ‘visible’ if it is readily visually differentiated from other bars; these other bars may still be visually apparent, but in a less prominent manner than a ‘visible’ bar. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will be described with reference to the accompanying drawings, in which 
         FIG. 1A  is a photograph of a personal GPS navigation device according to the present invention; 
         FIG. 1B  is a prior art GPS information screen; 
         FIGS. 2A-2D  are screen shots from an implementation showing a GPS signal strength indicator at varying levels; 
         FIG. 2E  is an expanded view of the navigation bar from an implementation, showing the GPS signal strength indicator in more detail; 
         FIG. 3  is a screen shot from an implementation showing how Point of Interest data can be inserted into a database running on the device; 
         FIGS. 4A-4B  are screen shots from an implementation showing how different kinds of Point of Interest icons can be selectively enabled/disabled for display; 
         FIGS. 5A-5E  are screen shots from an implementation showing how Point of Interest icons can be prioritised to reduce screen clutter; 
         FIG. 6A-6B  are screen shots from an implementation showing how moving Point of Interest icons can be displayed; 
         FIGS. 7A-7E  are screen shots from an implementation showing how actions can be associated with a Point of Interest icons; 
         FIGS. 8A-8D  are screen shots from an implementation showing how map auto-zooming occurs when approaching a decision point; 
         FIGS. 9A-9B  are screen shots from an implementation showing how the map simplifies at higher speeds; 
         FIG. 10A  is a screen shot from an implementation showing how the next major route change is displayed; 
         FIGS. 11A-11B  are screen shots from an implementation showing how a night mode display appears. 
     
    
    
     DETAILED DESCRIPTION 
     The present invention will be described with reference to an implementation from Palmtop Software BV of Amsterdam, Netherlands called TomTom Navigator™. Referring to  FIG. 1 , the TomTom Navigator GPS system runs on a PocketPC powered DPA, such as the Compaq iPaq  1  and comprises a GPS receiver  2  and navigation software running on the Compaq iPaq  1 . 
     In the TomTom Navigator GPS system, routes/roads are described in a database running on the personal GPS navigation device as lines—i.e. vectors (i.e. start point, end point, direction for a road, with an entire road being made up of many hundreds of such sections, each uniquely defined by start point/end point direction parameters). A map is then a set of such road vectors, plus points of interest (POIs), plus other geographic features like park boundaries, river boundaries etc, all of which are defined in terms of vectors. All map features (e.g. road vectors, POIs etc.) are defined in a co-ordinate system that corresponds or relates to the GPS co-ordinate system, enabling a device&#39;s position as determined through a GPS system to be located onto the relevant road shown in a map. 
     Route calculation uses complex algorithms applied to score large numbers of potential different routes. Once a route is calculated by the PDA, the PDA in effect has stored in a database a sequence of road names and actions to be done at pre-determined distances along each road of the route (e.g. after 100 meters; turn left into street x). 
     1. GPS Signal Strength Indicator 
       FIGS. 2A-D  show a typical navigation screen (aerial view) created by the TomTom Navigator GPS system for a vehicle driving down Central Park West in New York, N.Y., USA. The position of the vehicle is given by the arrow  5 . A navigator bar, indicated generally at  6 , includes essential navigation information. It also includes a GPS signal strength indicator  4 . The GPS signal strength indicator  4  is visible in normal navigation mode and hence there is no need to task away to a separate GPS information screen to see this information; minimising the need to task away from the main navigation mode screen (showing the map and current vehicle location) is very useful as the device is meant to be used as an in-vehicle navigation system and driver distractions need to be at a minimum. Further, its apparent similarity to the familiar network coverage indicator in a mobile telephone screen makes it an easily understood user interface element. 
     The GPS signal strength indicator  4  consists of 4 bars with the following functional meanings:
         4 bars visible: Received GPS signal is strong enough to give 3D fix at high level of accuracy ( FIG. 2A )   3 bars visible: Received GPS signal is strong enough to give a 3D fix; ( FIG. 2B )   2 bars visible: Received GPS signal is strong enough to give a 2D fix ( FIG. 2C )   1 bar visible: Received GPS Signal is present, but not strong enough to obtain a position fix ( FIG. 2D )   0 bars visible: No signal detected.       

       FIG. 2E  shows the navigation bar  6  in more detail. It includes the following:
         GPS signal strength indicator  4 . An indication of the number of satellites from which GPS signals are being received is also given—in this case  7 .   Name  8  of the current road or route being traveled along (Madison Avenue in this case)   Distance to next turning to be taken 9 (35 yards in this case)   Nature of next turning to be taken 10 (in this case, a right turn).
 
Further UI Features
       

     The following features are also present in the TomTom Navigator GPS system. Each may be used independently of any other feature (and independently of displaying the GPS signal strength indicator with the map in navigation mode). 
     2. Ability to Download POI 
     POIs are points of interest, such as museums, restaurants, petrol stations etc. The TomTom Navigator GPS system comes pre-loaded with several thousand POIs, which can automatically appear on a displayed map. POIs exist as a POI type and a longitude and latitude position in the TomTom Navigator GPS system database resident on the device. 
     An enhancement to the conventional use of POIs is to enable them to be downloaded to the device (e.g. over the internet or a wireless connection (using SMS or WAP etc) and inserted into the database.  FIG. 3  shows the menu screen listing three new POIs  11 , with location data; the user can choose to insert these into his database by selecting the ‘insert’ button  12 . 
     This approach enables third parties to supply POIs from a remote database over a WAN, with possibilities for promoting different POIs. For example, a national chain of gas stations could allow users to download to their personal GPS navigation devices the location of all of its gas stations, which could then be displayed with the correct logo at the correct map locations. The logos could also animate to draw attention to themselves. Location based advertising is also possible (for example, a department store with a sale on could allow POIs of its stores with a special ‘Sale’ logo to be downloaded). User can also create their own new categories of POIs and exchange them with others: hence, POIs for special interest categories can evolve, driven by the needs of users. An example might be that photographers could generate POIs for locations with outstanding views and store these POIs on not only their own personal GPS navigation devices, but also exchange them with other photographers. Motorists could identify particularly enjoyable roads with a new POI type and exchange these with others. Virtually any kind of location information can be categorised with a POI and hence captured in the TomTom Navigator GPS system database resident on the device for display on a map and also exchange with other users. 
     3. POI Selection 
     Proliferating the nature of possible POI stored could lead to considerable screen clutter, with much irrelevant information. Printed maps, for example, frequently include too much POI data, making it difficult to find a specific kind of POI of interest. 
     The TomTom Navigator GPS system addresses this by listing all POI types and allowing the user to select which particular types are to be displayed:  FIGS. 4A and 4B  show a typical selection of POI types; only the checked item(s) will be displayed on a map: in this case, only gas stations, as shown in  FIG. 4A  since only the gas station POI check box  13  is selected.  FIG. 4B  shows that check box de-selected: no gas stations will now be displayed on the map in navigation mode. 
     4. POI Prioritization 
     The TomTom Navigator maps are divided into grid cells (Navigator 1.0, for instance, uses a 4×5 grid). Within each cell, only a single POI is displayed on a map at a time. This reduces screen clutter.  FIGS. 5A-E  show a map of New York at progressively greater enlargement; enlargement is increased by the user moving the zoom control  14  down. 
     Hence, in  FIG. 5A , there is a single gas station indicated as being present in the central Manhattan area  15 . (As an aside, it should be noted that GPS signal strength indicator is still apparent at  16 ). Zoomed in, as shown in  FIG. 5B , there are three gas stations  16  in central Manhattan. Zoomed in still further, as shown in  FIG. 5C , there are many more now shown, plus POIs of other types, such as hotels (the bed icons,  18 ). Zooming in further still,  FIG. 5D , shows even more POIs. Further still,  FIG. 5E , shows restaurants (icon  19 ), as well as all hotels. 
     This logical introduction of different POI types, dependent on the zoom level is based on certain POIs (low-density POIs, like gas stations and amusement parks) being displayed in priority over others (high density POIs like restaurants). Further, certain high-density POIs are not displayed at all any more if you zoom out beyond a certain threshold (e.g. no restaurant POIs if map shows more than a certain number of square miles). 
     5. Moving POIs 
     Another useful feature of the TomTom Navigator GPS system is that POIs do not need to have a fixed location in the database: their location in the database can be regularly, continuously or occasionally updated to show a new location; when this happens, the associated POI icon&#39;s position on the map will automatically move to the newly defined location. This feature is useful for tracking assets (e.g. vehicles; people too) and utilises the feature note earlier of sharing POI data: a vehicle could send regular SMS messages with its current location (using its own GPS system) to a mobile telephone equipped personal GPS navigation system, which could then use the location co-ordinates in the SMS message to update a POI uniquely associated with that vehicle. As the vehicle location alters, its position will change on the map, as shown in  FIGS. 6A and 6B , where truck  20  can be seen moving down the route. Hence, a very low cost, yet sophisticated, asset tracking system can be deployed using this approach. 
     6. Associating an Action with a POI 
     Selecting a POI can trigger a related action, such as opening a window with information about or functions relating to the POI, or a communication application that enables the user to call/text etc. that POI, or a browser window that opens a web page relating to that POI. Triggering may be direct or indirect (i.e. there are intervening steps). 
       FIGS. 7A and 7B  illustrate opening a window with functions relating to the POI—in  FIG. 7A , the user has selected the icon for Manhattan Hotel  21 : when he does this, the name of the hotel  22  is displayed above the hotel POI icon. When the user selects the name  22 , pop up menu list ( 23  in  FIG. 7B  appears). Window  23  lists various functions relating to the Manhattan Hotel, such as navigating to it (i.e. making it the destination for a route calculation algorithm; the TomTom Navigator software then calculates a route from the current location to the Manhattan Hotel). Another option is “Nearby points of interest’  24 ; if selected, a list of nearby POIs is shown,  FIG. 7C , in ascending order of distance from the hotel. The user can see that 12 yards from the Manhattan Hotel is the Golden Eagle restaurant  25 . If the user selects this entry  25 , then more information on it is shown, including various contact numbers.  FIG. 7D  shows the information for a different hotel, this time in Berlin; if the user selects the web URL, then the device opens a browser window and opens the requested web page. If the user touches the telephone number, it is automatically called (assuming the device has phone capabilities). If the user selects the ‘Show on map’ item  26 , the hotel  27  is shown again on the map, a seen in  FIG. 7E . 
     7. Auto-Zooming of Map as Car Nears a Decision-Point 
     Another feature is that the map will automatically zoom-in when approaching a decision point, such as s turning, roundabout, intersection; merge etc. This ensures that the user can see detail when he needs it, without giving too much detail when it is not needed. 
       FIGS. 8A-D  show the user  30  turning right. In  FIG. 8A , the user  30  can see that there is a right turn ahead from the map at  31  and from the right turn arrow  32  on the navigation bar. The navigation bar shows that the turning is 210 yards ahead  33 . 
     As the user approaches the turn, the map progressively and automatically zooms in so that, at 100 yards from the turning,  FIG. 8B , the scale is considerably greater. 35 yards from the turning,  FIG. 8C , and the scale has increased even more. After the turn has been completed, the zoom returns to its default zoom level,  FIG. 8D . 
     8. Auto-Zooming Depending on the Speed of the Car 
       FIG. 9A  shows the vehicle  40  travelling at 70 mph (see navigation bar at  41 ) along route  42 . If the user were instead travelling at 7 mph, as shown in  FIG. 9B , then the map would be automatically zoomed in to show more detail. This ensures that the user can see the map extending far enough ahead to allow timely decisions to be made. In effect, the user sees a certain number of seconds ahead rather than a certain distance. 
     9. Screen Simplifies Above User Defined Speed 
     A related feature is that the screen simplifies above speed (which may be user defined): this reduces unnecessary screen clutter and fast moving but irrelevant detail. Hence, in  FIG. 9B , roundabout 44 is shown as the user is travelling slowly at 7 mph; but in  FIG. 9A , the roundabout detail is not shown at al as the vehicle is travelling at 70 mph. 
     10. Show Next Major Route Change 
       FIG. 10A  shows how the TomTom Navigator system can display the next major route change. In  FIG. 10A , it is exiting interstate highway 287/87: window  50  summarises this. This shows a user departing from familiar territory (e.g. home) that the main purpose of many coming instructions is to take him to a certain highway exit. Allows driver to relax on long motorway journey since he can see at a glance that his exit is still 275 miles  51  away. 
     This feature can also show a user that the main purpose of many coming instructions is to take him to a certain highway—which allows him to follow the road signs rather than the instructions. 
     11. Nightview 
     The conventional navigation mode view,  FIG. 11A , can be replaced with a night view mode,  FIG. 11B , which uses a light road against darker surroundings, plus lower brightness and very muted colors. The glare of the normal (daylight) colours, and the total amount of light coming from the whole PDA screen, can be bothersome and maybe even dangerous when the user drives at night). 
     APPENDIX 1 
     Navigator 2.0 Features 
     The following new features are present in the Navigator 2.0 software; this software runs on a Pocket PC powered PDA, such as the Compaq iPaq and provides a GPS based navigation system when the PDA is coupled with a GPS receiver. The combined PDA and GPS system is designed to be used as an in-car navigation system. 
     
       
         
               
               
             
               
               
               
             
               
               
             
           
               
                   
               
               
                 FEATURE 
                 COMMENT 
               
               
                   
               
             
             
               
                 Demonstrate route 
                 Allows user to see the entire proposed route in animated fashion as 
               
               
                 function 
                 if he is driving it. A fun feature, but also very useful for point-of- 
               
               
                   
                 sale purposes to catch the eye of potential purchasers of the 
               
               
                   
                 Navigator software and GPS system. 
               
               
                   
                 The user inputs his start position and required destination in the 
               
               
                   
                 normal manner into the Navigator software running on the PDA. 
               
               
                   
                 The user then selects the manner in which a travel route is 
               
               
                   
                 calculated: various modes could be offered, such as a ‘fast’ mode 
               
               
                   
                 that calculates the route very rapidly, but the route might not be the 
               
               
                   
                 shortest; a ‘full’ mode that looks at all possible routes and locates the 
               
               
                   
                 shortest, but takes longer to calculate etc. Other options are 
               
               
                   
                 possible, with a user defining a route that is scenic - e.g. passes the 
               
               
                   
                 most POI marked as views of outstanding beauty, or passes the 
               
               
                   
                 most POIs of possible interest to children or uses the fewest 
               
               
                   
                 junctions etc. 
               
               
                   
                 Roads themselves are described in the database as lines - i.e. vectors 
               
               
                   
                 (i.e. start point, end point, direction for a road, with an entire road 
               
               
                   
                 being made up of many hundreds of such sections, each uniquely 
               
               
                   
                 defined by start point/end point direction parameters). A map is 
               
               
                   
                 then a set of such road vectors, plus points of interest (POIs), plus 
               
               
                   
                 other geographic features like park boundaries, river boundaries etc, 
               
               
                   
                 all of which are defined in terms of vectors. All map features (e.g. 
               
               
                   
                 road vectors, POIs etc.) are defined in a co-ordinate system that 
               
               
                   
                 corresponds or relates to the GPS co-ordinate system, enabling a 
               
               
                   
                 device&#39;s position as determined through a GPS system to be located 
               
               
                   
                 onto the relevant road shown in a map. 
               
               
                   
                 Route calculation uses complex algorithms applied to score large 
               
               
                   
                 numbers of potential different routes. Once a route is calculated by 
               
               
                   
                 the PDA, the PDA in effect has stored in a database a sequence of 
               
               
                   
                 road names and actions to be done at pre-determined distances 
               
               
                   
                 along each road of the route (e.g. after 100 meters, turn left into 
               
               
                   
                 street x). 
               
               
                   
                 The user can ask for the entire journey along the route to be 
               
               
                   
                 simulated on a map displayed on the PDA: in the conventional 
               
               
                   
                 manner, the position of the car on the displayed map is marked with 
               
               
                   
                 an arrow; as the journey simulation progresses, the streets move past 
               
               
                   
                 the car arrow, which is optimally fixed approximately ⅓ rd  up from 
               
               
                   
                 the bottom of the map, and centered. This requires the database 
               
               
                   
                 sequence of road names and actions that define the route to be able 
               
               
                   
                 to be sequentially selected (say simulating progress at a rate that 
               
               
                   
                 allows the entire journey to be completed in 15 seconds) and for the 
               
               
                   
                 map to display simulated progress of the car along the vectors which 
               
               
                   
                 define the roads of the calculated route. 
               
               
                   
                 The car is hence shown actually navigating along the route calculated 
               
               
                   
                 by the Navigator software. In this way, a user can check that the 
               
               
                   
                 route looks acceptable; the user may for example, prefer a route that 
               
               
                   
                 avoids a certain region and he may want to confirm that the route 
               
               
                   
                 suggested by the program does bypass it. Or the user may simply 
               
               
                   
                 feel more comfortable driving a route that he has had fully described 
               
               
                   
                 and shown to him by the software before hand. 
               
               
                   
                 In a point of sale system, the simulation can continuously repeat. 
               
               
                 Alternative route 
                 A user could select an ‘avoid roadblock’ function that causes the 
               
               
                 function: ‘avoid 
                 system to recalculate a route on the basis that the road immediately 
               
               
                 roadblock’ 
                 ahead is blocked. 
               
               
                   
                 A route planning algorithm will work out an optimal route (optimal 
               
               
                   
                 may refer to criteria such as shortest time or shortest distance, or 
               
               
                   
                 some other factors) by exploring different routes and scoring them 
               
               
                   
                 against the required criteria. In this way, one route which best meets 
               
               
                   
                 the defied criteria is generated. If whilst actually driving along a 
               
               
                   
                 route, an unexpected event occurs that requires the user to detour 
               
               
                   
                 away from the pre-calculated route, such as a roadblock, the user can 
               
               
                   
                 inform the software that his immediate road ahead is blocked and 
               
               
                   
                 require the software to re-calculate a new route, taking his current 
               
               
                   
                 position as a new starting position, but taking the first turning 
               
               
                   
                 possible away from the old calculated route. This first turning might 
               
               
                   
                 be ahead or behind the current car position. The system hence, in 
               
               
                   
                 constructing the new route, explores a large number of possible 
               
               
                   
                 routes to the destination from the current position, but excludes the 
               
               
                   
                 road immediately ahead. 
               
               
                   
                 Selecting the ‘avoid roadblock’ function has to be fast and involve 
               
               
                   
                 the absolute minimum number of screen interactions to minimise 
               
               
                   
                 driver distraction. This can be achieved by the user being able to 
               
               
                   
                 switch from normal navigation mode (in which the current position 
               
               
                   
                 of the car is shown on a map) to a menu mode by pressing a key or 
               
               
                   
                 selecting any point on the screen; the menu mode displays a small 
               
               
                   
                 number of large icons, one of which is the ‘avoid roadblock’ option. 
               
               
                   
                 This can be selected with one touch; when this occurs, the software 
               
               
                   
                 re-calculates the route and gives instructions in the normal manner 
               
               
                   
                 (voice; on screen navigation prompts) to allow the user to proceed 
               
               
                   
                 to his destination but avoid the road immediately ahead. 
               
               
                 Alternative route 
                 Allows a user to easily and rapidly select a road to mark as blocked 
               
               
                 function: ‘avoid 
                 so that he can input information from real time traffic information 
               
               
                 specific road’ 
                 broadcast on the radio. 
               
               
                   
                 When listening to the radio, a user may hear that a specific road or 
               
               
                   
                 perhaps part of a motorway between defined junctions is blocked or 
               
               
                   
                 heavily congested. If that road is on the user&#39;s calculated route, even 
               
               
                   
                 though it might be many kilometres away, then he will want to have 
               
               
                   
                 the software recalculate a new route as soon as possible. The system 
               
               
                   
                 does this by calculating a route to the final destination using the 
               
               
                   
                 current position as a start position and exploring different routes to 
               
               
                   
                 the destination, but excluding the road indicated as to be avoided. 
               
               
                   
                 The new route will then be calculated using normal route planning 
               
               
                   
                 algorithms and the user diverted onto the new route. 
               
               
                   
                 Selecting the ‘avoid specific road’ function has also to be fast and 
               
               
                   
                 involve the absolute minimum number of screen interactions to 
               
               
                   
                 minimise driver distraction. This can be achieved by the user being 
               
               
                   
                 able to switch from normal navigation mode (in which the current 
               
               
                   
                 position of the car is shown on a map) to a menu mode by pressing 
               
               
                   
                 a key or selecting any point on the screen; the menu mode displays a 
               
               
                   
                 small number of large icons, several of which are named roads on 
               
               
                   
                 the route which, if selected, can be selected with one touch; when 
               
               
                   
                 this occurs, the software re-calculates the route and gives 
               
               
                   
                 instructions in the normal manner (voice; on screen navigation 
               
               
                   
                 prompts) to allow the user to proceed to his destination but avoid 
               
               
                   
                 the road immediately ahead. 
               
               
                   
                 Typically, one touch on the screen is needed to open a window 
               
               
                   
                 showing a list of future main roads (three currently are shown in 
               
               
                   
                 Navigator 2.0); one further touch to select a listed icon as blocked. 
               
               
                   
                 The system then recalculates an alternative route. 
               
               
                 Alternative route 
                 The system can also enable a user to mark certain points/regions as 
               
               
                 function: 
                 blocked or slow or to give penalties (or their inverse, awards) to a 
               
               
                 ‘penalties’ 
                 point/region to weight routing away from (or to) that point/region 
               
               
                   
                 and have the system auto calculate an alternative route. 
               
               
                   
                 Also, a user could penalise specific complex junctions on a simulated 
               
               
                   
                 route (see above) if they disliked them, or else could indicate that he 
               
               
                   
                 wanted fewer turnings and the device would then count the number 
               
               
                   
                 of turnings in alternative routes and give preference to the routes 
               
               
                   
                 with fewer turnings. 
               
               
                   
                 Route planning algorithms operate by assigning scores to different 
               
               
                   
                 possible routes in relation to different criteria (e.g. scores for the 
               
               
                   
                 time of journey, scores for the length of journey etc) and then 
               
               
                   
                 determining which route has the best overall score. Normally, the 
               
               
                   
                 user cannot interact directly with how the algorithm treats roads, 
               
               
                   
                 junctions and other route features. But in Navigator 2 it is possible: 
               
               
                   
                 the user can directly alter the way the route planning algorithm 
               
               
                   
                 scores a route by awarding penalties/awards to points/regions that 
               
               
                   
                 affect the route planning scoring. The route planning algorithm 
               
               
                   
                 stores a list of all roads/junctions in vector form associated with 
               
               
                   
                 each calculated route from start to destination; each item (e.g. road 
               
               
                   
                 section, turning etc.) will typically have several parameters associated 
               
               
                   
                 with it that are used in the scoring process to evaluate a best route. 
               
               
                   
                 Hence, it is straightforward to alter the route scoring based on giving 
               
               
                   
                 different weightings to different kinds of items. For example, one 
               
               
                   
                 user might dislike junctions; in which case, the route scoring could 
               
               
                   
                 count junction numbers in alternate routes and then weight more 
               
               
                   
                 favourably routes with fewer junctions. Similarly, roads within 
               
               
                   
                 certain user defined regions could have some of their scoring 
               
               
                   
                 parameters altered to change the likelihood of a route being selected 
               
               
                   
                 using them (either to increase or decrease the likelihood of 
               
               
                   
                 selection). 
               
               
                 Alternative route 
                 A user can also simply select ‘alternative route’ if he simply wants to 
               
               
                 function: auto 
                 see another possible route: the system then recalculates a route, not 
               
               
                 generate 
                 using at least 80% of the roads from the prior route. 
               
               
                 Alternative route 
                 A user can select ‘normal’, ‘strict’ and ‘fast’ planning modes: each 
               
               
                 planning: 
                 results in different route planning algorithms being used that 
               
               
                 selecting 
                 calculate the route either normally, or strictly (which may take many 
               
               
                 calculation modes 
                 minutes as a great many permutations are explored) or quickly, 
               
               
                   
                 (which may take a few seconds only as many simplifying 
               
               
                   
                 assumptions are made about the optimal route). 
               
               
                 Large soft 
                 The device can display a large keyboard, far larger than conventional 
               
               
                 keyboard 
                 screen based keyboards on PDAs. This allows a user to input text 
               
               
                   
                 more easily - and without taking the device out of the cradle or off 
               
               
                   
                 the dashboard - and even using his finger rather than the stylus. 
               
               
                   
                 The optimal dimensions on a iPaq are: 
               
               
                   
                 QWERTY/AZERTY keyboard images: 
               
               
                   
                 Horizontal spacing: 25 pixels center to center (button to button) 
               
               
                   
                 Vertical spacing: 32 pixels center to center (button to button) 
               
               
                   
                 ABC keyboard image: 
               
               
                   
                 Horizontal spacing: 40 pixels center to center 
               
               
                   
                 Vertical spacing: 32 pixels center to center 
               
               
                   
                 NOTE: Numeric keyboard image is mixed (has both small and big 
               
               
                   
                 keys) NOTE: Some keys might be 1 pixel smaller in width than 
               
               
                   
                 other keys (aesthetics) therefore the center to center might be 
               
               
                   
                 different from key to key. 
               
               
                   
                 The individual key size in pixels is (width, height): 
               
               
                   
                 36 × 28 (ABC keyboard image) 
               
               
                   
                 21 × 28 (QWERTY/ASERTY keyboard image) 
               
               
                   
                 46 × 28 (arrow keys on QWERTY/AZERTY keyboard images) 
               
               
                   
                 70 × 28 (space/back keys on QWERTY/AZERTY keyboard images) 
               
               
                   
                 NOTE: Some keys might be 1 pixel smaller in width than other keys 
               
               
                   
                 (aesthetics) 
               
               
                   
                 The total image sizes for different keyboards (width, height) are as 
               
               
                   
                 follows: 
               
               
                   
                 240 × 155 (ABC keyboard image- as seen in Navigate to Address for 
               
               
                   
                 example) 
               
               
                   
                 240 × 155 (QWERTY keyboard image - as seen in Navigate to 
               
               
                   
                 Address for example) 
               
               
                   
                 240 × 155 (AZERTY keyboard image - as seen in Navigate to 
               
               
                   
                 Address for example) 
               
               
                   
                 240 × 62 (2 line NUM/Arrowkeys image - as seen in Navigate to 
               
               
                   
                 Address, 3rd page: “Enter house number or crossing”) 
               
               
                   
                 240 × 31 (1 line Arrow key image - as seen in ‘navigate to recent’ for 
               
               
                   
                 example) 
               
               
                   
                 NOTE: This includes white-space edges in the range of 1 to 3 pixels. 
               
               
                   
                 The above sizes enable a soft keyboard to be displayed that a user 
               
               
                   
                 can readily operate with one finger when the device is mounted on a 
               
               
                   
                 dashboard cradle with the car moving and without being 
               
               
                   
                 significantly distracted from driving. 
               
               
                   
                 Tolerances to the above sizes are approximately 25% (plus or 
               
               
                   
                 minus). 
               
               
                 Waypoints 
                 If you pass a location of interest on your route (e.g. while driving), 
               
               
                   
                 you can store your present location by a very simple action (e.g. a tap 
               
               
                   
                 on the screen or by issuing a voice command). This stores a marker 
               
               
                   
                 in a database of waypoints; in essence the co-ordinates of the 
               
               
                   
                 location of interest. The waypoint can be marked on the map itself 
               
               
                   
                 with a POI icon. Later, the user can retrieve and use it (or even 
               
               
                   
                 annotate and store it). For example, if marked as a POI on a map, 
               
               
                   
                 the user could select the POI on the map, which would cause an 
               
               
                   
                 annotation window to open, into which the user could input text 
               
               
                   
                 (e.g. “great bookshop here”). 
               
               
                 House numbers 
                 Each of the following features, on its own or in combination 
               
               
                   
                 (Navigator 2.0 uses them in combination): 
               
             
          
           
               
                   
                 (1) 
                 Show no house numbers on the screen except on request, when 
               
               
                   
                   
                 the user taps the screen. Then the relevant information pops up, 
               
               
                   
                   
                 and disappears again after a few seconds 
               
               
                   
                 (2) 
                 Show the house number range for the piece of street between 
               
               
                   
                   
                 two corners that the user clicked on 
               
               
                   
                 (3) 
                 show the street name and house number(s) for the exact spot 
               
               
                   
                   
                 the user clicked on 
               
               
                   
                 (4) 
                 odd numbers are always shown in certain fixed colours (e.g. 
               
               
                   
                   
                 yellow-on-dark blue) and odd numbers are always shown in 
               
               
                   
                   
                 different fixed colours (e.g. white-on-black). If both even and 
               
               
                   
                   
                 odd numbers are shown (which is the usual case), odd numbers 
               
               
                   
                   
                 are always shown before even numbers. 
               
             
          
           
               
                 Postal code input 
                 User can input postal code of a city instead of typing in the actual 
               
               
                   
                 city name, when defining a home or destination which will typically 
               
               
                   
                 be far longer (and hence inconvenient with a small on-screen 
               
               
                   
                 keyboard). 
               
               
                   
                 Furthermore, this input variant is perfect for devices with numeric 
               
               
                   
                 keyboards (e.g. mobile telephones) - since all countries except the 
               
               
                   
                 United Kingdom use all-numeric postal codes that uniquely identify 
               
               
                   
                 cities. 
               
               
                   
                 This is useful when specifying a destination with a long name; it 
               
               
                   
                 requires there to be database of city postal codes that can be 
               
               
                   
                 matched against, ideally with the system guessing the entire postal 
               
               
                   
                 code from the initial letters/numbers so that the user does not even 
               
               
                   
                 have to enter the entire city code. 
               
               
                 Geocoding 
                 Adding WGC 84 (or other co-ord) system data automatically to an 
               
               
                   
                 address in a contacts list by using the co-ord system knowledge of an 
               
               
                   
                 integrated navigation program. 
               
               
                   
                 The Navigator software is programmed with the WGC84 (or other 
               
               
                   
                 co-ord system) co-ordinates of roads and house numbers along a 
               
               
                   
                 road. Hence, when a user defines a start or destination address as 
               
               
                   
                 part of the normal route planning process, the software determines 
               
               
                   
                 the associated WGC84 co-ordinates; it can then also mark the start 
               
               
                   
                 and destination positions on the map with appropriate icons. It can 
               
               
                   
                 share this facility with a contacts application: a software component 
               
               
                   
                 could take a contact address from the database used by the contact 
               
               
                   
                 application and export it to the engine in the navigation software 
               
               
                   
                 that converts addresses to WGC84 co-ordinates. This engine could 
               
               
                   
                 then determine the WGC84 co-ordinates and then return that 
               
               
                   
                 WGC84 data to a new field in the database used by the contacts 
               
               
                   
                 application - the new field stores and makes available the WGC84 
               
               
                   
                 data within the contacts application or other applications. 
               
               
                 Contacts 
                 Auto-generating an option within the Contacts application to 
               
               
                 integration 
                 navigate to that contact within the navigation program and/or show 
               
               
                   
                 the location of the contact on a mapping application. 
               
               
                 Hot list of most 
                 System offers a “navigate to nearby point of interest” option. This 
               
               
                 important POIs 
                 first provides a “hot list” of POI icons for the small set of “most 
               
               
                   
                 often used” POI types. 
               
               
                   
                 The list is initialized to generally useful POI types (for car drivers) 
               
               
                   
                 like petrol station, restaurants, parking spots etc. Hence, a user can 
               
               
                   
                 very readily ask the program to navigate him to the nearest petrol 
               
               
                   
                 station etc. 
               
               
                   
                 The system in effect recalculates a route with the closest relevant 
               
               
                   
                 POI as the destination and the current location as the start. 
               
               
                   
                 The user can manually adjust the types to suit his own needs. 
               
               
                   
                 Furthermore, at least one of the icons will self-adjust to the most 
               
               
                   
                 recently used type not already in the list. 
               
               
                 POI along the 
                 Searching for POIs would normally be done by defining a point and 
               
               
                 route 
                 searching outwards from that point to locate relevant POIs. 
               
               
                   
                 Applying this approach to finding POIs along a route would be 
               
               
                   
                 impossible on a PDA because you would in effect be replicating the 
               
               
                   
                 search for all points along the route (potentially millions of separate 
               
               
                   
                 searches for a long journey, which would be too great a load). We 
               
               
                   
                 reverse this approach by taking each relevant POI and seeing if it is 
               
               
                   
                 on a vectoir/line that that also defines part of the route - a simple 
               
               
                   
                 and fast correlation process between POIs and route lines, that can 
               
               
                   
                 rapidly be repeated for all POIs of relevance.