Abstract: A method and system for organizing and storing map data that facilitates use of the map data by navigation application programs such as those in navigation systems. The map data represent geographic features located in a region. The map data are organized into parcels such that each parcel contains a portion of the map data. The map data contained in each parcel represent those geographic features contained in a corresponding separate one of a plurality of rectangular areas located in the region. Each rectangular area has a uniform dimension in a first coordinate direction but has a dimension in the other coordinate direction such that the map data that represent the geographic features contained in the rectangular area are close to, but do not exceed, a maximum data size for a parcel.

Abstract: An in-vehicle navigation system includes a receiver for receiving real-time traffic information (RTTI), a database for storing routine trip information, and a processor for running a regular route application. The regular route application includes a learning mode program and an operational mode program. The learning mode program records information regarding trips regularly taken by a vehicle and populates the database with records of routine trip information. The recorded trip information can include driver identifiers, trip departure times, origin points, destination points, dates of travel, days of travel, and route data. When the vehicle begins a new trip, the operational mode program determines whether the vehicle is engaging in a routine trip. This is accomplished by comparing current vehicle location or departure time information to routine trip information in the database.

Abstract: A navigation system includes a feature that allows a user to specify a type of point of interest (or business chain) and then receive a reminder when the user is in proximity to a location of the point of interest of the specified type (or business chain) while traveling in a geographic region.

Abstract: A method and system that provides end users with the ability to exchange routing data. A route recorder application on a first computing system provides a first end user with the ability to define a route formed of specific road segments and store data that represent the route in a data file. The data file is distributed to a second end user who uses the data that represent the route in a second computing system to provide guidance for following the route.

Abstract: A computing architecture for a motorized land-based vehicle is disclosed. The computing architecture includes a data network comprised of a plurality of interconnected processors, a first group of sensors responsive to environmental conditions around the vehicle, a second group of sensors responsive to the vehicle's hardware systems, and a map database containing data that represent geographic features in the geographic area around the vehicle. A vehicle-environment modeling program, executed on the data network, uses the outputs from the first and second groups of sensors and the map database to provide and continuously update a data model that represents the vehicle and the environmental around the vehicle, including geographic features, conditions, structures, objects and obstacles around the vehicle. Vehicle operations programming applications, executed on the data network, use the data model to determine desired vehicle operation in the context of the vehicle's environment.

Abstract: Methods for comparing three-dimensional space curves are provided. Such methods are particularly useful for map matching in in-vehicle navigation systems as well as for other applications that require accurate positioning of the vehicle with respect to the underlying map data referenced by the system. Additionally, they are useful in measuring and/or evaluating the accuracy of a geographic database. Two angles that define the angular orientation of a three dimensional space curve are determined at corresponding locations for each of a first space curve and a second space curve. The variance of the relationship between the angle pairs at corresponding locations along the first and second space curves is utilized to determine the similarity between the first and second space curves despite any spatial translation and angular rotation between the first and second space curves.

Abstract: A data collection system including a data glove is used by a researcher to safely and efficiently collect and input data for a geographic database. The data collection system is transported by the researcher along roads in a geographic area. As the data collection system is being transported, the positions of the data collection system are determined. The researcher inputs data into the data collection system through the glove by hand and/or finger gestures. The data collection system stores data indicating a determined position with a type of data associated with the gestures. The data obtained by the data collection system is displayed so that the researcher can add or modify data records in the geographic database. The data obtained by the data collection system is used to add data to or modify data in the geographic database.

Abstract: A method for comparing geometric shapes to each other is disclosed. When used for vehicle positioning, the present method determines which map path of several candidate map paths best matches an actual path traveled by the vehicle as measured by sensors. The vehicle path and each candidate map path are generalized to a given degree of generalization, thereby yielding an overall trend of the vehicle path and overall trends of each of the candidate map paths. The trend of the vehicle path is compared to the trend of each of the candidate map paths. Based on these comparisons, one or more candidate map paths may be eliminated. If more than one map path remains, the vehicle path and each of the remaining map paths are generalized again, this time to a lesser degree of generalization, and comparisons are made between the trend of the vehicle path and the trend of each of the remaining map paths. Based on these comparisons, one or more map paths may be eliminated.

Abstract: A method for representing a route along a road network in a geographic region is disclosed. A database includes data representations of intersections of roads in the geographic region. Associated with the data representation for each intersection of roads are data indicating one or more nominal paths through the intersection. The nominal paths through an intersection identify, for each road segment by which the represented intersection can be entered, one and only one road segment from which the represented intersection is exited. The route is represented by indicating each intersection at which the route deviates from the nominal path into the intersection.

Abstract: A method for updating a geographic database is disclosed. Data collecting equipment is installed in each of a plurality of vehicles each of which also has a navigation system. The data collection equipment is used to collect data while the vehicles are being driven along roads by their respective users. In addition, a method for assigning a confidence level to geographic data is disclosed. The confidence level is assigned to the geographic data as an attribute. In addition, a method for determining a position of a vehicle by sensing roadside structures is disclosed. Data indicating positions of roadside structures are contained in a geographic database. By matching positions of sensed roadside structures to data in the geographic database that indicates the positions of the structures, the position of the vehicle while traveling can be determined.

Abstract: A geographic database for use with a navigation application program that provides navigation features to an end-user. The geographic database includes a plurality of data records of a first type and a plurality of data records of a second type. The plurality of records of the first type are organized into a plurality of parcels, each of which includes a plurality of data records of the first type and the plurality of records of the second type are organized into a plurality of parcels, each of which includes a plurality of data records of the second type. The parcels of data records of the first type are interleaved with the parcels of data records of the second type. This interleaving enables navigation functions that use these different types to access these different types more quickly and efficiently, thereby enhancing navigation system performance.

Abstract: A turn detection algorithm is used by a navigation system for determining position and heading of a vehicle relative to a road network represented by a geographic database used by the navigation system. A dead-reckoned position and heading are determined along a plurality of road segments in the road network using sensor measurements of a distance traveled by the vehicle and a change in heading of the vehicle. A vehicle trajectory history is formed and then continuously updated. The vehicle trajectory history includes sensor-derived data representing the vehicle trajectory over a relatively small, chosen distance. The sensor-derived data in the vehicle trajectory history include total turn (i.e., heading change of the vehicle), vehicle state (e.g., travelling straight, turning or reversing in turn direction within a specified small distance) and type of vehicle maneuver. These data represent the trajectory of the vehicle for that distance and are kept in a memory.

Abstract: A program and method for route calculation for use with a navigation system and used with a map database that represents a road network in a geographic region. A route calculation program is adapted to find at least one solution route between a first location on a road network and a second location on the road network. The route calculation program includes a first search tree associated with the first location and a second search tree associated with the second location. Each search tree is adapted to hold gates. Each of the gates represents a physical position on the road network and a direction from the position to another location along a path on the road network. The route calculation program also includes at least one priority queue associated with one of the search trees. The priority queue assigns a priority to one of the gates in the associated search tree based upon an evaluation using a search algorithm.

Abstract: A system and method of providing incremental updates for a geographical data set for use in navigation systems. The system and method include organizing updates of geographical data set into a series of transactions. Each of the transactions includes a transaction identifier that uniquely identifies the transaction, and n steps to be applied to the geographical data set to complete the transaction. All the steps of the transaction are required to be successfully applied in order for the transaction to be completed, otherwise, the entire transaction is not applied.

Abstract: An improved system and method for specifying physical locations when using applications run on navigation systems or other computer platforms that provide navigation- or map-related functions. When requesting a navigation- or map-related function from such an application, a user specifies a physical location using a keyword instead of specifying the physical location conventionally, such as by street address. A keyword database relates keywords to physical locations. The application uses the keyword database, or a copy thereof, to find data indicating the physical location associated with the keyword specified by the user. Preferably, physical locations are defined in the keyword database in terms of data in a corresponding navigable database. The application then performs the requested navigation- or map-related function using the data indicating the physical location associated with the keyword. The keyword database is built using input from users.

Abstract: Methods for comparing three-dimensional space curves are provided. Such methods are particularly useful for map matching in in-vehicle navigation systems as well as for other applications that require accurate positioning of the vehicle with respect to the underlying map data referenced by the system. Additionally, they are useful in measuring and/or evaluating the accuracy of a geographic database. Two angles that define the angular orientation of a three dimensional space curve are determined at corresponding locations for each of a first space curve and a second space curve. The variance of the relationship between the angle pairs at corresponding locations along the first and second space curves is utilized to determine the similarity between the first and second space curves despite any spatial translation and angular rotation between the first and second space curves.

Abstract: A geographic database for use with a navigation application program that provides navigation features to an end-user. The geographic database includes a plurality of data records of a first type and a plurality of data records of a second type. The plurality of records of the first type are organized into a plurality of parcels, each of which includes a plurality of data records of the first type and the plurality of records of the second type are organized into a plurality of parcels, each of which includes a plurality of data records of the second type. The parcels of data records of the first type are interleaved with the parcels of data records of the second type. This interleaving enables navigation functions that use these different types to access these different types more quickly and efficiently, thereby enhancing navigation system performance.

Abstract: A navigation system provides a user thereof with warnings or advisories about toll gates that require exact change. The warnings or advisories are provided when the navigation system calculates a solution route to a destination specified by the user. The warnings or advisories are also provided when the user queries the navigation system about a particular specified portion of a road. The navigation system uses a geographic database that includes data about roads in a geographic region. The geographic database includes data about toll gates located along portions of roads including data about whether a toll gate along a portion or a road requires exact change.

Abstract: A data construction for storing data efficiently and a method for forming and using the data construction is disclosed. The method comprises representing a set of actual data values from an original source of data with an alternative representation. One or more parameters of a formula are determined to approximate the set of actual data values in the original source of data. For each actual data value in the original source of data, the difference between the actual data value and the value predicted therefor by the formula is determined. The difference for each actual data value is stored in a data construction on the medium along with the one or more parameters. The alternative representation preserves the information content of the actual data values from the original source of data while reducing the storage requirements for storing the information on a medium.

Abstract: A feature implemented on a navigation system in a vehicle whereby the user of the vehicle selects one or more types of audio programs and associates each type of audio program with a specific location along a predetermined route. As the vehicle is being driven along the route, audio programs of the types selected by the user are obtained and stored in a memory. When the vehicle reaches the location associated with one of the selected types of audio programming, the stored audio program of the selected type is presented to the user.