Aisin Aw Co., Ltd.

Yusuke Oohashi

Yohei Ando

Daisuke Sakaki

Hiroyoshi Masuda

A navigation device includes a GPS receiver, map data including tunnel data and periodically acquires a vehicle's speed to provide guidance on the current position N acquired at the GPS receiver, and when GPS radio waves become unreceivable after the vehicle passes a tunnel entrance, calculates a travel distance according to a vehicle speed and a time T up to a branch, and continues providing guidance on the current position up to the branch. After passing the branch, the navigation device suspends guidance, calculates a distance La between the branch and a tunnel exit, which is shorter, and when GPS radio waves are not received even after a movement distance from the branch exceeds distance La, after passing the branch, determines a road whose distance is longer as the road being traveled, and provides guidance on the current position.

Terminal device and guidance program

Track information generating devices, methods, and programs acquire a self-contained navigation track of a vehicle indicated by time-series pieces of self-contained navigation information, and acquire a GPS track that is a track of the vehicle indicated by time-series pieces of GPS information. The devices, methods, and compare the self-contained navigation track with the GPS track to acquire a first correction amount for obtaining the highest degree of coincidence between the self-contained navigation track and the GPS track and then correct the self-contained navigation information using a second correction amount that is smaller than the first correction amount.

Track information generating device, track information generating method, and computer-readable storage medium

Track information generating devices, methods, and programs acquire a self-contained navigation track of a vehicle indicated by time-series pieces of self-contained navigation information, and acquire a GPS track of the vehicle indicated by time-series pieces of GPS information. The devices, methods, and programs compare the self-contained navigation track with the GPS track to correct the self-contained navigation information so as to reduce a difference between the self-contained navigation track and the GPS track.

Track information generating devices, methods, and programs acquire a self-contained navigation track of a vehicle indicated by time-series pieces of self-contained navigation information, acquire a matching track of the vehicle indicated by time-series pieces of information determined through a map matching process is determined as a road the vehicle is traveling, and acquire a degree of reliability of the matching track. The devices, methods, and programs acquire a GPS track that is a track of the vehicle indicated by time-series pieces of GPS information, acquire a degree of reliability of the GPS track, and set the one of the GPS track and the matching track having a higher degree of reliability as a correction target track to correct the self-contained navigation information so as to reduce a difference between the self-contained navigation track and the correction target track.

Devices, methods, and programs identify a leading candidate point by calculating a cost for candidate points on a road, and match a vehicle position to the identified leading candidate point. The devices, methods, and programs acquire an estimated vehicle position based on dead reckoning navigation, acquire a GPS position of the vehicle, and set the candidate points for the vehicle position on nearby roads. The devices, methods, and programs calculate for each candidate point a normal cost of the candidate point with respect to the estimated position and a correction cost that corresponds to a value L(the value Lbeing found by subtracting a width W of a road having the candidate point from a distance d between the GPS position and the candidate point), and identify the leading candidate point based on a total cost of the normal cost and the correction cost for each candidate point.

Navigation device, method, and program

Devices, methods, and programs provide vehicle navigation. A speculative heading error is acquired that corresponds to the reliability of the vehicle heading, which corresponds to an estimated vehicle position that was calculated using a previous vehicle position as a reference. A best candidate position or the estimated vehicle position is set as the vehicle position depending on whether a heading difference between the vehicle heading and a heading when the estimated point is corrected to the best candidate position falls within the speculative heading error. Therefore, false matching can be further reduced and prompt recovery is possible even if a false match occurs.

Devices, methods, and programs correct an estimated path found by dead reckoning navigation. A point correlation value s is calculated based on a distance to a reliability circle whose radius is a speculative maximum error e that indicates a distance of an error range with respect to a GPS position. A correlation value Sp of an estimated path and a correlation value Sq of a candidate path are calculated from cumulative values of the point correlation values s. A correction that moves the estimated path is not performed if the correlation value Sq of the candidate path becomes worse than the correlation value Sp of the estimated path, and the correction of the estimated path is performed if the correlation value Sq of the candidate path does not become worse than the correlation value Sp of the estimated path. Thus, false matching can be further reduced, and the travel path can be suitably corrected.

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Sapporo, Japan

Yusuke Oohashi