Abstract: A communication control system includes: a communication device that receives real-time information necessary for a vehicle control from an information delivery device via one of base stations; and a control device that controls the vehicle based on the real-time information. The communication device generates prediction information indicative of an index of remaining time before a communicating base station is switched with timing while the vehicle is running. The control device reduces a service level of the vehicle control for supporting at least one of a driving determination and a driving operation performed by a driver of the vehicle within the remaining time, which is shown in the prediction information.

Abstract: A communication control system includes: a communication device that receives real-time information necessary for a vehicle control from an information delivery device via one of base stations; and a control device that controls the vehicle based on the real-time information. The communication device generates prediction information indicative of an index of remaining time before a communicating base station is switched with timing while the vehicle is running. The control device reduces a service level of the vehicle control for supporting at least one of a driving determination and a driving operation performed by a driver of the vehicle within the remaining time, which is shown in the prediction information.

Abstract: A current position detector for a vehicle includes: an angular speed sensor; a speed sensor; a GPS receiver; a traveling trajectory estimating element for estimating a relative trajectory based on an orientation change amount and a traveling distance, and for estimating a traveling trajectory based on the relative trajectory and a GPS signal; and an error estimating element for estimating and correcting each error of an angular speed signal, a speed signal and the GPS signal. The error estimating element estimates a gain error of the angular speed signal such that an attachment angle gain error attributed to an attachment angle of the angular speed sensor and an angular speed gain error attributed to a non-linear gain property of the angular speed sensor are independently estimated.

Abstract: A current position detector for a vehicle includes: an angular speed sensor; a speed sensor; a GPS receiver; a traveling trajectory estimating element for estimating a relative trajectory based on an orientation change amount and a traveling distance, and for estimating a traveling trajectory based on the relative trajectory and a GPS signal; and an error estimating element for estimating and correcting each error of an angular speed signal, a speed signal and the GPS signal. The error estimating element estimates a gain error of the angular speed signal such that an attachment angle gain error attributed to an attachment angle of the angular speed sensor and an angular speed gain error attributed to a non-linear gain property of the angular speed sensor are independently estimated.

Abstract: There is a need for improving the accuracy of estimating a gain error for an angular velocity sensor. An error estimation section and a correction section are provided as well as a gyroscope that detects an angular velocity of a vehicle. The error estimation section assumes the gain error of the gyroscope to be a state quantity and finds an estimated value for the gain error using a Kalman filter. Based on the gain error found by the error estimation section, the correction section corrects a gain correction amount used for gain correction of values detected by the gyroscope. The correction section corrects the gain correction amount dedicated to right turn based on the gain error found by the error estimation section when the vehicle is assumed to turn right. The correction section corrects the gain correction amount dedicated to left turn based on the gain error found by the error estimation section when the vehicle is assumed to turn left.

Abstract: There is a need for improving the accuracy of estimating a gain error for an angular velocity sensor. An error estimation section and a correction section are provided as well as a gyroscope that detects an angular velocity of a vehicle. The error estimation section assumes the gain error of the gyroscope to be a state quantity and finds an estimated value for the gain error using a Kalman filter. Based on the gain error found by the error estimation section, the correction section corrects a gain correction amount used for gain correction of values detected by the gyroscope. The correction section corrects the gain correction amount dedicated to right turn based on the gain error found by the error estimation section when the vehicle is assumed to turn right. The correction section corrects the gain correction amount dedicated to left turn based on the gain error found by the error estimation section when the vehicle is assumed to turn left.

Abstract: A navigation device changes a position determination accuracy of a receiver for satellite navigation to a higher accuracy in the following cases: when the subject vehicle approaches a destination, the subject vehicle runs on a road not described in map information, when the subject vehicle approaches an intersection at which the road is branched at a narrow angle within a predetermined distance, when the subject vehicle is running on a narrow street, when the subject vehicle is running on one of adjacent parallel roads, when self-contained sensors are calibrated, and other like occasions. In the other cases, the navigation device changes the position determination accuracy of the receiver to a low accuracy. When the receiver is caused to execute low-accuracy position determination, power supply to receiver's operation required only for high-accuracy position determination is prohibited.

Abstract: A map evaluation system is equipped with a car navigation device and a map evaluation device. The car navigation system generates difference data indicating a location where a difference is present between a vehicle position path and a road location obtained from a map database. The car navigation device then sends the difference data along with additional data relating to accuracy of the difference data. The map evaluation device determines accuracy for the difference data based on the additional data. When the accuracy degree of the difference data is determined to be proper, the map evaluation device increments by one a determining count of a group including the difference data. When the determining count exceeds a given count, a portion to be amended on the map database is displayed on a monitor based on the difference data stored in a difference database.

Abstract: A navigation device changes a position determination accuracy of a receiver for satellite navigation to a higher accuracy in the following cases: when the subject vehicle approaches a destination, the subject vehicle runs on a road not described in map information, when the subject vehicle approaches an intersection at which the road is branched at a narrow angle within a predetermined distance, when the subject vehicle is running on a narrow street, when the subject vehicle is running on one of adjacent parallel roads, when self-contained sensors are calibrated, and other like occasions. In the other cases, the navigation device changes the position determination accuracy of the receiver to a low accuracy. When the receiver is caused to execute low-accuracy position determination, power supply to receiver's operation required only for high-accuracy position determination is prohibited.

Abstract: A map evaluation system is equipped with a car navigation device and a map evaluation device. The car navigation system generates difference data indicating a location where a difference is present between a vehicle position path and a road location obtained from a map database. The car navigation device then sends the difference data along with additional data relating to accuracy of the difference data. The map evaluation device determines accuracy for the difference data based on the additional data. When the accuracy degree of the difference data is determined to be proper, the map evaluation device increments by one a determining count of a group including the difference data. When the determining count exceeds a given count, a portion to be amended on the map database is displayed on a monitor based on the difference data stored in a difference database.