Abstract: This invention relates to a display method and apparatus in a navigation system. More specifically, this invention relates to a navigation-based method and apparatus to provide guidance information to a driver without repeatedly performing route recalculation when the driver makes slight deviation from the road he or she is travelling on. In one embodiment of the present invention, guidance information is displayed on a user interface without generating a route. For example, when a vehicle is travelling either on a freeway or a surface road, a distance indicator provides distance information to nearby freeway junctions or streets. In another embodiment, when the vehicle is deviated from a calculated route, a route deviation detecting unit may detect whether the vehicle is deviating from the calculated route to a predetermined extent. If not, the original calculated route will not be recalculated.

Abstract: This invention relates to a display method and apparatus in a navigation system. More specifically, this invention relates to a navigation-based method and apparatus to provide guidance information to a driver without repeatedly performing route recalculation when the driver makes slight deviation from the road he or she is travelling on. In one embodiment of the present invention, guidance information is displayed on a user interface without generating a route. For example, when a vehicle is travelling either on a freeway or a surface road, a distance indicator provides distance information to nearby freeway junctions or streets. In another embodiment, when the vehicle is deviated from a calculated route, a route deviation detecting unit may detect whether the vehicle is deviating from the calculated route to a predetermined extent. If not, the original calculated route will not be recalculated.

Abstract: A computational scheme for an INS which utilizes micro-electro mechanical systems (MEMS) sensors resolves issues of unnecessarily large computational burden and numerical instability which happen in using conventional methods using high-end inertial sensors. The first aspect is to omit computing Earth radii of curvatures that were used in a high-frequency application. The second aspect is to ignore the Earth rotation and the rotation of the local tangent plane with respect to Earth which are much smaller than noise and bias in the MEMS sensor output. The last aspect is to assume that the absolute amount of the platform pitch and roll angles is less than 90 degrees. According to the aspects noted above, the computational load will be one-fourth of the conventional method without degradation of accuracy.

Abstract: A map matching method and apparatus for a navigation system estimates a location of the navigation system on a correct road segment when a GPS signal is invalid. The map matching method creates a database of pairs of locations at which the navigation system encountered GPS signal loss and recovery in the first time. The navigation system conducts a map matching processing when the GPS signal is lost in the second time at the recorded location by incorporating various additional factors to match the current position with a correct road segment. The various additional factors, in addition to the measured data by a dead reckoning process, include road class, road accessibility, road angle, proximity to candidate road, etc.

Abstract: A computational scheme for an INS which utilizes micro-electro mechanical systems (MEMS) sensors is disclosed resolving issues of unnecessarily large computational burden and numerical instability which happen in using conventional methods using high-end inertial sensors. The first aspect to reduce computational burden in MEMS application is to omit computing Earth radii of curvatures that were used in a high-frequency application. The second aspect is to ignore the Earth rotation and the rotation of the local tangent plane with respect to Earth in the computation which are much smaller than noise and bias in the MEMS sensor output. The last aspect is to assume that the absolute amount of the platform pitch and roll angles is less than 90 degrees. This assumption results in only four parameters required to track in the direction cosine matrix describing the transformation from the local tangent plane to the platform where all the nine elements are tacked in the conventional method.

Abstract: A map matching method and apparatus for a navigation system estimates a location of the navigation system on a correct road segment when a GPS signal is invalid. The map matching method creates a database of pairs of locations at which the navigation system encountered GPS signal loss and recovery in the first time. The navigation system conducts a map matching processing when the GPS signal is lost in the second time at the recorded location by incorporating various additional factors to match the current position with a correct road segment. The various additional factors, in addition to the measured data by a dead reckoning process, include road class, road accessibility, road angle, proximity to candidate road, etc.

Abstract: A method and apparatus for a navigation system for selecting a location on a three-dimensional map view has a pyramid cursor that identifies a focused location and a means to change a viewing angle. The three-dimensional map view shows the three-dimensional image of roads and flat surfaces but not buildings or other structures erected on the surfaces. The three-dimensional image of the building and other structure only within the area of the pyramid icon will be displayed on the screen. The navigation system allows the user to change the viewing angle of the three-dimensional view up to a top view so that a user can select a particular location on the top view.

Abstract: A traffic routing method and apparatus for navigation system provides accurate prediction of departure and travel times by using current and past traffic incident information. The traffic routing method includes the steps of forming a database of traffic incident information which is constituted by current traffic incident data and past traffic incident data, setting a condition and priority for retrieving the traffic incident information, retrieving the traffic incident information from the database based on the condition and priority, and applying the retrieved traffic incident information to a route to a destination and calculating a predicted travel time and a departure time.