Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
220 words
A navigation apparatus for a vehicle which, by being provided with an input of a desired destination, performs course exploration up to the destination to furnish a course to the destination while keeping track of present position of the vehicle, said apparatus comprising: storage means for storing road network data including road network information having intersections as reference points, means for detecting the steering angle of the vehicle, means for detecting the travel distance of the vehicle, computing means for computing the vehicle orientation and trajectory from said detected steering angle and said detected travel distance, turning-point detecting means for detecting a turning point from said detected steering angle and said computed vehicle orientation and computing the position of the turning point, and road selecting means for determining an actual vehicle turning angle from the turning-point position and comparing the actual vehicle turning angle with the turning angle of a road leading to an intersection obtained from the road network data, and selecting a road in a travelling direction which passes through the intersection based on the comparison, wherein said vehicle turning angle is determined based on three points, namely, the turning-point position, the turn starting point and the turn end points, and said present position is calculated based on the selected road in the travelling direction and intersection information.
Claim 2
Dependent Claim
220 words
A navigation apparatus for a vehicle which, by being provided with an input of a desired destination, performs course exploration up to the destination to furnish a course to the destination while keeping track of present position of the vehicle, said apparatus comprising: storage means for storing road network data including road network information having intersections as reference points, means for detecting the steering angle of the vehicle, means for detecting the travel distance of the vehicle, computing means for computing the vehicle orientation and trajectory from said detected steering angle and said detected travel distance, turning-point detecting means for detecting a turning point from said detected steering angle and said computed vehicle orientation and computing the position of the turning point, and road selecting means for determining an actual vehicle turning angle from the turning-point position and comparing the actual vehicle turning angle with the turning angle of a road leading to an intersection obtained from the road network data, and selecting a road in a travelling direction which passes through the intersection based on the comparison, wherein said vehicle turning angle is determined based on three points, namely, the turning-point position, the turn starting point and the turn end points, and said present position is calculated based on the selected road in the travelling direction and intersection information.
Claim 3
Dependent Claim
32 words
A navigation apparatus according to claim 1, wherein said turning-point detecting means detects a turning point on the condition that said steering angle exceeds a threshold value and a predetermined rotational angle.
Claim 4
Dependent Claim
42 words
A navigation apparatus according to claim 1, wherein said road selecting means selects, as a road in the travelling direction, a connecting road for which a difference between said vehicle turning angle and a turning angle of the connecting road is minimum.
Claim 5
Dependent Claim
45 words
A navigation apparatus according to claim 3, wherein a said connecting road, for which said difference between said vehicle turning angle and said turning angle of the connecting road lies within a range of predetermined value, is selected as said road in the travelling direction.
Claim 6
Dependent Claim
53 words
A navigation apparatus according to claim 3, wherein said road selecting means determines information corresponding to three points, namely, the turning-point position, the turn starting point and the turn end points, in accordance with an intersection range distance on the condition that an intersection range is passed through without a turn being detected.
Claim 7
Dependent Claim
31 words
A navigation apparatus according to claim 1, which includes distance error correcting means for correcting the present position on a road in a travelling direction based on the detected turning-point position.